Berrien Springs, MI, United States

Recent publications

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    ABSTRACT: Microsporidia are obligate intracellular parasites with extremely reduced genomes and a dependence on host-derived ATP. The microsporidium Encephalitozoon cuniculi proliferates within a membranous vacuole and we investigated how the ATP supply is optimized at the vacuole-host interface. Using spatial EM quantitation (stereology), we found a single layer of mitochondria coating substantial proportions of the parasitophorous vacuole. Mitochondrial binding occurred preferentially over the vegetative "meront" stages of the parasite, which bulged into the cytoplasm, thereby increasing the membrane surface available for mitochondrial interaction. In a broken cell system mitochondrial binding was maintained and was typified by electron dense structures (>10nm long) bridging between outer mitochondrial and vacuole membranes. In broken cells mitochondrial binding was sensitive to a range of protease treatments. The function of directly bound mitochondria, as measured by the membrane potential sensitive dye JC-1, was indistinguishable from other mitochondria in the cell although there was a generalized depression of the membrane potential in infected cells. Finally, quantitative immuno-EM revealed that the ATP-delivering mitochondrial porin, VDAC, was concentrated at the mitochondria-vacuole interaction site. Thus E. cuniculi appears to maximize ATP supply by direct binding of mitochondria to the parasitophorous vacuole bringing this organelle within 0.020 microns of the growing vegetative form of the parasite. ATP-delivery is further enhanced by clustering of ATP transporting porins in those regions of the outer mitochondrial membrane lying closest to the parasite.
    Full-text · Article · Nov 2013 · Cellular Microbiology
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    ABSTRACT: College students are one of the most at-risk population groups for food poisoning, due to risky food safety behaviors. Using the Likert Scale, undergraduate students were asked to participate in a Food Safety Survey which was completed by 499 students ages 18-25. Data was analyzed using SPSS and AMOS statistical software. Four conceptual definitions regarding food safety were defined as: general food safety, bacterial food safety, produce food safety, and politics associated with food safety. Knowledge seems to be an important factor in shaping students attitudes regarding general and bacterial safety. Ethnicity plays a role in how people view the politics of food safety, and the safety of organic foods.
    Full-text · Article · Feb 2013 · Nutrients
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    ABSTRACT: There is inconclusive evidence for the effectiveness of cryotherapy for the treatment of exercised induced muscle damage (EIMD). Small sample sizes and treatment applications that did not correspond to evidence based practice are limitations in previous studies that may have contributed to these equivocal findings. The purpose of this study was to examine the effectiveness of daily multiple applications of ice on EIMD throughout the 72-hour recovery period, an icing protocol that more closely resembles current clinical practice. Thirty-three subjects were assigned to either the cryotherapy group (n=23) or control group (n=10). EIMD was induced through repeated isokinetic eccentric contractions of the right hamstring muscle group. The experimental group received ice immediately after induction of EIMD and continued to ice 3x/day for 20-minutes throughout the 72 hours; the control group received no intervention. Isometric torque, hamstring length, pain, and biochemical markers (CK, ALT, and AST) were assessed at baseline, 24, 48, and 72 hours. Both groups demonstrated a significant change (p < .05) in all dependent variables compared to baseline, but there was no difference between groups except for pain. The cryotherapy group had significantly (p= .048) less pain (3.0 cm ± 2.1) compared to the control (5.35 cm ± 2.5) at 48 hours. Although not statistically significant, the cryotherapy group had greater range of motion and lower CK and AST means at 72 hours compared to the control group. Repeated applications of ice can decrease the pain associated with EIMD significantly at 48 hours post EIMD. While the results may not be unique, the methodology in this study was distinctive in that we used a larger sample size and an icing protocol similar to current recommended treatment practice.
    Full-text · Article · Jan 2013 · The Journal of Strength and Conditioning Research
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    ABSTRACT: Exosomes are secreted by many cell types and display multiple biological functions. The ability to both rapidly detect and quantify exosomes in biological samples would assist in the screening of agents that interfere with their release, and which may therefore be of clinical relevance. Nanoparticle tracking analysis, which detects the size and concentration of exosomes, was used to monitor the inhibition of exosome secretion from MDA-MB-231 breast cancer cells expressing inhibitory RNA targeted for Rab27a, a known component of the exosome pathway. Inhibition of both Rab27a and Rab27b was observed, resulting in alterations to intracellular CD63+ compartments and the release of fewer exosomes into the culture medium, as determined by nanoparticle tracking analysis and confirmed by immunoblotting and protein quantification. These data show that nanoparticle tracking analysis can be used effectively and rapidly to monitor the disruption of exosome secretion.
    No preview · Article · Oct 2012 · Experimental Cell Research
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    ABSTRACT: The crystal-field and Zeeman splittings of the energy levels of Nd3+(4f3) 2S+1LJ in hexagonal phase AlN have been investigated. The multiplet manifolds of Nd3+(4f3) analyzed include the ground state, 4I9/2, and excited states 4I11/2, 4I13/2, 4F3/2, 4F5/2, 2H(2)9/2, 4F7/2, 4S3/2, 4G5/2, and 2G7/2. Experimental energy levels were obtained from analyses of the 12 K cathodoluminescence spectra from Nd3+-implanted films of AlN, and from the 15 K photoluminescence excitation spectra and the site-selective combined excitation-emission spectra (CEES) recently reported for in situ Nd-doped hexagonal AlN grown by plasma-assisted molecular beam epitaxy (PA-MBE). CEES results identify a main site and two minority sites for Nd3+ in both samples. Transition line strengths attributed to the ion in minority sites are relatively stronger in Nd:AlN than in Nd:GaN. The 15 K experimental Zeeman splitting of Nd3+ are analyzed in the PA-MBE grown AlN samples and compared with the Zeeman splitting observed in Nd:GaN. The crystal-field and Zeeman splittings were modeled using a parametrized Hamiltonian consisting of atomic and crystal-field terms. We considered possible site distortion due to the size of the implanted Nd ion that would reduce the site symmetry from C3v to C3 or C1h. However, no significant improvement was obtained using these lower symmetry models, leading us to conclude that C3v symmetry is a reasonable approximation for the main site Nd3+ ions in AlN.
    Full-text · Article · Sep 2012 · Optical Materials Express
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    ABSTRACT: In humans, coping behaviour is an action taken to soothe oneself during or after a stressful or threatening situation. Some human behaviours with physiological functions also serve as coping behaviours, for example, comfort sucking in infants and comfort eating in adults. In birds, the behaviour of preening, which has important physiological functions, has been postulated to soothe individuals after stressful situations. We combine two existing modelling approaches - logistic regression and Darwinian dynamics - to explore theoretically how a behaviour with crucial physiological function might evolve into a coping behaviour. We apply the method to preening in colonial seabirds to investigate whether and how preening might be co-opted as a coping behaviour in the presence of predators. We conduct an in-depth study of the environmental correlates of preening in a large gull colony in Washington, USA, and we perform an independent field test for comfort preening by computing the change in frequency of preening in gulls that were alerted to a predator, but did not flee.
    No preview · Article · Aug 2012 · Journal of Biological Dynamics
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    ABSTRACT: A search for single-top production, ep→etX, has been made with the ZEUS detector at HERA using an integrated luminosity of . Events from both the leptonic and hadronic decay channels of the W boson resulting from the decay of the top quark were sought. For the leptonic mode, the search was made for events with isolated high-energy leptons and significant missing transverse momentum. For the hadronic decay mode, three-jet events in which two of the jets had an invariant mass consistent with that of the W were selected. No evidence for top production was found. The results are used to constrain single-top production via flavour-changing neutral current (FCNC) transitions. The ZEUS limit excludes a substantial region in the FCNC tuγ coupling not ruled out by other experiments.
    Full-text · Article · Jan 2012 · Physics Letters B
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    ABSTRACT: The Institute of Medicine noted that effective substance abuse treatment (SAT) programs integrate individual therapeutic approaches with transitional/ancillary services. In addition, research suggests that type of ownership impacts SAT services offered and that Medicaid plays a key role in SAT access. Data from the National Survey of Substance Abuse Treatment Services for the years 2000 and 2002-2006 were used to examine relationships among SAT program Medicaid acceptance, program ownership, and transitional/ancillary service accessibility. Multivariate logistic regression models controlling for state- and program-level contextual factors were used to analyze the data. Nonprofit SAT programs were significantly more likely to offer transitional/ancillary services than for-profit programs. However, programs that accepted Medicaid, regardless of ownership, were significantly more likely to offer most transitional/ancillary services. The data suggest that Medicaid may play a significant role in offering key transitional/ancillary services related to successful treatment outcome, regardless of program ownership type.
    No preview · Article · Dec 2011 · Journal of substance abuse treatment
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    ABSTRACT: Obesity and ageing are both characteristics of the human population that are on the increase across the globe. It has long been established that ageing is the major risk factor for neurodegenerative conditions such as Alzheimer's disease, and it is becoming increasingly evident that obesity is another such factor. Leptin resistance or insensitivity has been uncovered as a cause of obesity, and in addition the leptin signalling system is less potent in the elderly. Taken together, these findings reveal that this molecule may be a link between neurodegeneration and obesity or ageing. It is now known that leptin has beneficial effects on both the survival and neurophysiology of the neurons that are lost in Alzheimer's disease suggesting that it may be an important research target in the quest for strategies to prevent, halt, or cure this condition.
    Full-text · Article · Oct 2011 · Current Gerontology and Geriatrics Research
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    ABSTRACT: Walnuts contain a number of potentially neuroprotective compounds like vitamin E, folate, melatonin, several antioxidative polyphenols and significant amounts of n-3 α-linolenic fatty acid. The present study sought to determine the effect of walnuts on verbal and non-verbal reasoning, memory and mood. A total of sixty-four college students were randomly assigned to two treatment sequences in a crossover fashion: walnuts-placebo or placebo-walnuts. Baseline data were collected for non-verbal reasoning, verbal reasoning, memory and mood states. Data were collected again after 8 weeks of intervention. After 6 weeks of washout, the intervention groups followed the diets in reverse order. Data were collected once more at the end of the 8-week intervention period. No significant increases were detected for mood, non-verbal reasoning or memory on the walnut-supplemented diet. However, inferential verbal reasoning increased significantly by 11·2 %, indicating a medium effect size (P = 0·009; d = 0·567). In young, healthy, normal adults, walnuts do not appear to improve memory, mood or non-verbal reasoning abilities. However, walnuts may have the ability to increase inferential reasoning.
    Full-text · Article · Sep 2011 · The British journal of nutrition
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    ABSTRACT: Drug resistance is a major hurdle in the global battle against tuberculosis (TB). In tackling this problem it is important to understand both how resistance emerges as well as the ways in which multi-drug and extensively drug-resistant TB (M/XDR-TB) may be successfully treated. The biggest problem with treatment is the lack of effective drugs. Exciting developments have been made in this area over recent years with useful drugs being found from older agents as well as new discoveries. Patent applications are being made for novel agents and are also possible as new use for older agents such as thioridazine. A flourishing drug pipeline is critical if we are to make progress in the management of M/XDR-TB.
    No preview · Article · May 2011 · Recent Patents on Anti-Infective Drug Discovery
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    ABSTRACT: Vegetarians exhibit a wide diversity of dietary practices, often described by what is omitted from their diet. When a vegetarian diet is appropriately planned and includes fortified foods, it can be nutritionally adequate for adults and children and can promote health and lower the risk of major chronic diseases. The nutrients of concern in the diet of vegetarians include vitamin B(12), vitamin D, ω-3 fatty acids, calcium, iron, and zinc. Although a vegetarian diet can meet current recommendations for all of these nutrients, the use of supplements and fortified foods provides a useful shield against deficiency. A vegetarian diet usually provides a low intake of saturated fat and cholesterol and a high intake of dietary fiber and many health-promoting phytochemicals. This is achieved by an increased consumption of fruits, vegetables, whole-grains, legumes, nuts, and various soy products. As a result of these factors, vegetarians typically have lower body mass index, serum total and low-density lipoprotein cholesterol levels, and blood pressure; reduced rates of death from ischemic heart disease; and decreased incidence of hypertension, stroke, type 2 diabetes, and certain cancers than do nonvegetarians.
    No preview · Article · Dec 2010 · Nutrition in Clinical Practice
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    ABSTRACT: There have been many publications in recent years reporting on the quantity of physical activity among college students using indirect indicators such as steps walked per day or time spent on physical activities. The purpose of this study was to describe the trends of physical fitness related to BMI and body fat among university students between 1996 and 2008. The results showed a significant decline in the average fitness levels measured as an estimation of VO(2max) for male and female students (p < 0.001 for both sexes). The linear trend for BMI by years was not significant for both sexes (p for males = 0.772, p for females = 0.253). On average, in the last 13 years, % body fat was increasing 0.513%/year for males and 0.654%/year for females. There is a significant indirect correlation between the student's VO(2max) levels and % body fat, r = -0.489; p < 0.001 for males; and r = -0.416, p < 0.001 for females. Approximately 23.9% of the variance in the VO(2max) levels in males and 17.3% in females can be explained by the variance in % body fat. The results support recent findings that physical fitness among college students is declining and body fatness is increasing.
    Full-text · Article · Oct 2010 · Nutrients
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    ABSTRACT: Spontaneous oscillator synchrony has been documented in a wide variety of electrical, mechanical, chemical, and biological systems, including the menstrual cycles of women and estrous cycles of Norway Rats (Rattus norvegicus). In temperate regions, many colonial birds breed seasonally in a time window set by photoperiod; some studies have suggested that heightened social stimulation in denser colonies can lead to a tightened annual reproductive pulse. It has been unknown, however, whether the analog of menstrual synchrony occurs in birds—that is, whether avian ovulation cycles can synchronize on a daily timescale within the annual breeding pulse. We report every-other-day clutch-initiation and egg-laying synchrony in a breeding colony of Glaucous-winged Gulls (Larus glaucescens) and show that the level of synchrony declined with decreasing colony density. We also pose a mathematical model based on the hypothesis that preovulatory luteinizing hormone surges synchronize through social stimulation. Model predictions are consistent with observations. Finally, we suggest a procedure for identifying synchronous egg laying in other colonies and species.
    Full-text · Article · Jul 2010 · The Auk
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    ABSTRACT: Recent studies of lensing clusters reveal that it might be fairly common for a galaxy cluster that the X-ray centre has an obvious offset from its gravitational centre which is measured by strong lensing. We argue that if these offsets exist, then X-rays and lensing are indeed measuring different regions of a cluster, and may thus naturally result in a discrepancy in the measured gravitational masses by the two different methods. Here we investigate theoretically the dynamical effects of such lensing–X-ray offsets and compare with observational data. We find that for typical values, the offset alone can give rise to a factor of 2 difference between the lensing and X-ray-determined masses for the core regions of a cluster, suggesting that such ‘offset effect’ may play an important role and should not be ignored in our dynamical measurements of clusters.
    Full-text · Article · Jun 2010 · Monthly Notices of the Royal Astronomical Society
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    ABSTRACT: We have combined the thermo-chemical disc code ProDiMo with the Monte Carlo radiative transfer code MCFOST to calculate a grid of ∼300 000 circumstellar disc models, systematically varying 11 stellar, disc and dust parameters including the total disc mass, several disc shape parameters and the dust-to-gas ratio. For each model, dust continuum and line radiative transfer calculations are carried out for 29 far-infrared, sub-mm and mm lines of [Oi], [Cii], 12CO and o/p-H2O under five inclinations. The grid allows us to study the influence of the input parameters on the observables, to make statistical predictions for different types of circumstellar discs and to find systematic trends and correlations between the parameters, the continuum fluxes and the line fluxes. The model grid, comprising the calculated disc temperature and chemical structures, the computed spectral energy distributions, line fluxes and profiles, will be used in particular for the data interpretation of the HERSCHEL open time-key program GASPS. The calculated line fluxes show a strong dependence on the assumed ultraviolet excess of the central star and on the disc flaring. The fraction of models predicting [Oi] and [Cii] fine-structure lines fluxes above HERSCHEL/PACS and SPICA/SAFARI detection limits is calculated as a function of disc mass. The possibility of deriving the disc gas mass from line observations is discussed.
    Full-text · Article · Jun 2010 · Monthly Notices of the Royal Astronomical Society Letters
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    ABSTRACT: The objective of the study was to examine whether reasons to adopt vegetarian lifestyle differ significantly among generations. Using a Food Frequency Questionnaire (FFQ), we identified that 4% of the participants were vegans, 25% lacto-ovo-vegetarians, 4% pesco-vegetarians and 67% non-vegetarian. Younger people significantly agreed more with the moral reason and with the environmental reason. People ages 41-60 significantly agreed more with the health reason. There are significant differences across generations as to why people choose to live a vegetarian lifestyle.
    Full-text · Article · May 2010 · Nutrients
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    ABSTRACT: This paper examines whether predatory behaviour of young cats predicts adult predatory activity. Many measures of predatory behaviour over the 4 to 12 week age period correlated with those seen at 6 months of age. On certain measures of behaviour, individual rankings within litters were maintained between the two age periods. Some predatory measures in kittens failed to correlate with those of adults because individuals that were poor predators when young caught up with their littermates as adults. Kitten social play patterns were found to correlate with adult predatory behaviour to differing extents.ZusammenfassungDiese Abhandlung untersucht die Beziehungen zwischen räuberischem Verhalten bei jungen Katzen und dem späteren rauberischen Verhalten der-selben ausgewachsenen Tiere. Viele Meßwerte solchen Verhaltens junger Katzen korrelieren mit dem räuberischen Verhalten der ausgewachsenen Tiere, wenn Mäuse als Beute dienten; das gait für nur wenige Meßwerte, wenn Vögel genommen wurden. Einzelne Jungtiere, die auf einigen Verhaltensskalen höher oder niedriger eingestuft wurden als andere Katzen vom gleichen Wurf, erhiel-ten auch als ausgewachsene Tiere mehr bzw. weniger Punkte. Einige Meßwerte räuberischen Verhaltens bei jungen Katzen ließen sich mit dem Verhalten der ausgewachsenen Tiere nicht in Beziehung bringen. Das lag nicht an Unter-schieden im Gewicht oder Geschlecht der Versuchstiere, sondern daran, daß einzelne Tiere, die als junge Katzen im Rauben weniger geschickt waren, als Erwachsene ihre Wurfgeschwister wieder einholten.Einige soziale Spiele junger Katzen stehen mit dem räuberischen Verhalten ausgewachsener Tiere in engerer Beziehung als andere.
    No preview · Article · Apr 2010 · Ethology
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    ABSTRACT: Male Bengalese finches, Lonchura striata var. domestica, learn their song from an adult male conspecific with whom they can interact at 35 to 70 days of age and normally-raised males fail to reproduce song which they have only heard before or after this time. Birds which have been raised by their mother alone and those which have been deprived of a song tutor during the learning phase produce abnormal songs with indistinct elements and little or no phrase structure; this is typical of males which fail to hear adult song during their development. These songs are unstable and are replaced by normal songs, if there is an opportunity to learn from an adult male conspecific. Presumably, this flexibility in the time when young males learn acts as a safeguard to ensure that normal conspecific song is produced.These results bear striking similarity to those on zebra finch song development. Differences between the two species, especially in the learning of call notes by female zebra finches, are discussed.
    No preview · Article · Apr 2010 · Ethology
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    ABSTRACT: Young male zebra finches exposed to a series of adult males during their sensitive phase for song learning tended to learn from several of them, in contrast to those exposed to two or more tutors simultaneously. There is a tendency to learn more from later tutors, either because the memory of their elements over-writes that of earlier ones or because sensitivity is greater at this stage. No clear relation could be found between features of the song or behaviour of tutors and whether or not they were copied. In common with earlier studies, tutor song output, beyond a certain minimum was found to be unimportant.
    No preview · Article · Apr 2010 · Ethology
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    ABSTRACT: From 1980 to 1998, Washington's Bald Eagle (Haliaeetus leucocephalus) population increased at an annual rate of 10%. Over the same time period, foraging activity of Bald Eagles at marine bird breeding colonies also increased. From 1993 to 2008, we observed foraging-related behavior of Bald Eagles on Violet Point, Protection Island. This island hosts more than 70% of the breeding seabirds in Washington's inner seaways and serves as an important rookery for harbor seals (Phoca vitulina). We found that (1) eagles landed more frequently in seal haul-out (beach) areas than in gull-nesting (non-beach) areas of Violet Point, and that subadult eagles were more likely to land in gull-nesting areas than were adult eagles; (2) the presence of eagles on the beach was positively related to the presence of harbor seals on the beach; (3) a greater-than-expected number of adult eagles as compared with subadult eagles preyed on gull chicks; (4) subadult and adult eagles that attempted prey capture were equally successful at snatching gull chicks from the gull colony; (5) eagles were more likely to prey on gull eggs in tall grass than on gull eggs in sparse vegetation. Prey remains beneath one eagle nest on the island did not accurately reflect the range and relative frequencies of observed eagle predation events. Although seal afterbirths and dead pups constitute a major component of the diet of Bald Eagles on the island, the effect of eagles on live seals is probably negligible. In contrast, direct predation and indirect effects of eagle activity on Glaucous-winged Gull (Larus glaucescens) reproductive success may be substantial and may have been partly responsible for a 44% decrease in the number of gull nests in the colony from 1993–2008.
    No preview · Article · Mar 2010 · Journal of Raptor Research
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    ABSTRACT: AbstractA paper in this journal by Fraser MacBride, ‘Can Ante Rem Structuralism Solve the Access Problem?’, raises important issues concerning the epistemological goals and burdens of contemporary philosophy of mathematics, and perhaps philosophy of science and other disciplines as well. I use a response to MacBride's paper as a framework for developing a broadly holistic framework for these issues, and I attempt to steer a middle course between reductive foundationalism and extreme naturalistic quietism. For this purpose the notion of entitlement is invoked along the way, suitably modified for the present anti-foundationalist setting.
    No preview · Article · Feb 2010 · The Philosophical Quarterly
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    ABSTRACT: Absorption and fluorescence spectra observed between 1950 and 320 nm at sample temperatures of 8, 78, and 293 K, representing more than 900 transitions between 24 multiplets 2S+1 L(J) of Ho3+(4f(10)) split by the crystal field, have been analyzed in Czochralski-grown single crystals of Ho3+ doped-yttrium gallium garnet (Y3Ga5O12 or YGG). The Ho3+ ions replace Y3+ ions in sites of D_2 symmetry during crystal growth. Associated with each multiplet manifold are 2J+1 nondegenerate crystal-field split sublevels (Stark levels) characterized by one of four different irreducible representations (irreps) associated with D_2 symmetry. The energy and irrep assignments for individual experimental Stark levels were established by an algorithm that makes use of the selection rules for electric-dipole (ED) and magnetic-dipole (MD) transitions between Stark levels. Nearly degenerate Stark levels (quasidoublets) in several manifolds have been observed and investigated by magneto-optical methods reported in a separate study. Of the 252 predicted Stark levels associated with the 24 multiplet manifolds, 241 were experimentally determined of which 161 had symmetry irreps unambiguously identified by the algorithm method and confirmed by crystal-field modeling studies. A final least-squares fitting between 241 calculated-to-experimental Stark levels was obtained with a standard deviation of 4.86 cm(-1) (rms error of 4.60 cm(-1)). The algorithm works best for identifying irreps when neighboring excited Stark levels are sufficiently separated so that a pattern of temperature-dependent ("hot band") transitions can be unambiguously associated with each excited Stark level.
    Full-text · Article · Dec 2009 · Journal of Applied Physics
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    ABSTRACT: While the internet is emerging as an important transforming mechanism for health care and public health, questions remain about its limitations. Growing evidence indicates that a significant proportion of internet health information consumers is engaging treatment strategies inconsistent with professional recommendations. This study aimed to distinguish internet users who report non-adherence behavior from their counterparts based on several personal and environmental determinants. Using information obtained via the internet to refuse or discontinue treatment recommended by a doctor or dentist proved to be a widespread (11.2%) behavior. Internet health information bolstered non-adherence appears strongly linked with personal determinants such as anxiety, diminishing health, and gender – a pattern consistent with prior adherence research – and with environmental determinants including the perceived importance of both internet health information and internet-facilitated interpersonal interactions as well as using the internet as a social support vehicle.
    Full-text · Article · Nov 2009 · Computers in Human Behavior
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    ABSTRACT: In this article we report the results of a study of needle-using behaviors in a street-recruited, noninstitutionalized sample of intravenous drug users (IVDUs) in Miami-Dade County. Survey data, elicited from 230 IVDUs, indicate a statistically significant relationship between injection frequency and antibody seropositivity for the Human Immunodeficiency Virus (HIV). Self-reported needle-sharing behavior and use of safe houses (i.e., shooting galleries) are also related to infection. Observational data, gathered using ethnographic techniques, identify standard cleaning practices, drug sharing between syringes, and accidental punctures as additional risks of HIV infection for IVDUs. In-depth interview data on values associated with needle use indicate that interventions focused on needle cleaning can be effective in this population.
    No preview · Article · Oct 2009 · Medical Anthropology Quarterly
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    ABSTRACT: Isolated photon production in deep inelastic ep scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 320 pb(-1). Measurements were made in the isolated-photon transverse-energy and pseudorapidity ranges 4 < E(T)(gamma) < 15 GeV and 0.7 < eta(gamma) < 0.9 for exchanged photon virtualities, Q(2), in the range 10 < Q(2) < 350 GeV(2) and for invariant masses of the hadronic system W(X) > 5 GeV. Differential cross sections are presented for inclusive isolated photon production as functions of Q(2), x, E(T)(gamma) and eta(gamma). Leading-logarithm parton-shower Monte Carlo simulations and perturbative QCD predictions give a reasonable description of the data over most of the kinematic range.
    Full-text · Article · Sep 2009 · Physics Letters B
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    ABSTRACT: This article demonstrates the complexity of the type 1 diabetes regimen and describes the physician's role in safely promoting self-management of diabetes by youth. Literature describing type 1 diabetes and the required regimen, issues related to regimen adherence by youth, demonstration of the magnitude of the regimen, and implications for physicians are addressed. A task analysis and tool for physicians is presented that contains over 600 tasks. Given the magnitude of the regimen, issues related to the physician's promotion of the gradual transfer of regimen control to youth are illustrated. The importance of understanding broad areas of the regimen (eg, "insulin injection") as not one task but many is emphasized, as is the need to explore adherence within regimen areas to pinpoint problems related to poor metabolic control. The article also examines how managed care influences the approach that a physician may take to communicate the requirements of the complex regimen to youth and parents. It is concluded that a developmentally sensitive approach must be taken that promotes youths' internalization of the importance of regimen tasks, and suggestions are provided for accomplishing this in a gradual manner that promotes developmentally appropriate involvement of youth in the regimen without premature responsibility.
    No preview · Article · Sep 2009 · Postgraduate Medicine
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    ABSTRACT: It is the position of the American Dietetic Association that appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases. Well-planned vegetarian diets are appropriate for individuals during all stages of the life cycle, including pregnancy, lactation, infancy, childhood, and adolescence, and for athletes. A vegetarian diet is defined as one that does not include meat (including fowl) or seafood, or products containing those foods. This article reviews the current data related to key nutrients for vegetarians including protein, n-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B-12. A vegetarian diet can meet current recommendations for all of these nutrients. In some cases, supplements or fortified foods can provide useful amounts of important nutrients. An evidence- based review showed that vegetarian diets can be nutritionally adequate in pregnancy and result in positive maternal and infant health outcomes. The results of an evidence-based review showed that a vegetarian diet is associated with a lower risk of death from ischemic heart disease. Vegetarians also appear to have lower low-density lipoprotein cholesterol levels, lower blood pressure, and lower rates of hypertension and type 2 diabetes than nonvegetarians. Furthermore, vegetarians tend to have a lower body mass index and lower overall cancer rates. Features of a vegetarian diet that may reduce risk of chronic disease include lower intakes of saturated fat and cholesterol and higher intakes of fruits, vegetables, whole grains, nuts, soy products, fiber, and phytochemicals. The variability of dietary practices among vegetarians makes individual assessment of dietary adequacy essential. In addition to assessing dietary adequacy, food and nutrition professionals can also play key roles in educating vegetarians about sources of specific nutrients, food purchase and preparation, and dietary modifications to meet their needs.
    No preview · Article · Aug 2009 · Journal of the American Dietetic Association

  • No preview · Article · Apr 2009 · Northwestern Naturalist
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    ABSTRACT: Recently, vegetarian diets have experienced an increase in popularity. A vegetarian diet is associated with many health benefits because of its higher content of fiber, folic acid, vitamins C and E, potassium, magnesium, and many phytochemicals and a fat content that is more unsaturated. Compared with other vegetarian diets, vegan diets tend to contain less saturated fat and cholesterol and more dietary fiber. Vegans tend to be thinner, have lower serum cholesterol, and lower blood pressure, reducing their risk of heart disease. However, eliminating all animal products from the diet increases the risk of certain nutritional deficiencies. Micronutrients of special concern for the vegan include vitamins B-12 and D, calcium, and long-chain n-3 (omega-3) fatty acids. Unless vegans regularly consume foods that are fortified with these nutrients, appropriate supplements should be consumed. In some cases, iron and zinc status of vegans may also be of concern because of the limited bioavailability of these minerals.
    Full-text · Article · Apr 2009 · American Journal of Clinical Nutrition
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    ABSTRACT: The purpose of this article is to demonstrate the complexity of the type 1 diabetes regimen and to highlight the essential role of the diabetes educator in safely training and implementing the myriad skills in a developmentally appropriate manner for children and adolescents. A review of literature and a task analysis were preformed and suggest that the complexity of the regimen is often not adequately addressed. Reviewed research assessed the regimen using measures with on average about 25 items while the task analysis contains over 600 tasks. The article discusses implications for clinical practice, including implications for measurement in research, targeting of interventions by diabetes educators, and the gradual transfer of regimen control to youth. It is argued that given the magnitude of the self-management task, education cannot be accomplished in the limited time that general practice physicians, pediatricians, or endocrinology specialists can spend with each patient. It is concluded that youth must be helped to internalize the importance of the regimen tasks and that transfer of these tasks to youth requires a developmentally sensitive approach to education. Diabetes educators serve an essential role in which they help young patients and their parents manage and master this overwhelming experience through promoting youth's involvement in tasks when full responsibility is not yet appropriate. The regimen is too complex for youth to undertake self-management without multidisciplinary support.
    Full-text · Article · Mar 2009 · The Diabetes Educator

  • No preview · Article · Jan 2009 · Journal of Vertebrate Paleontology
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    ABSTRACT: Las aves marinas se mueven a lo largo del día a través de ambientes cambiantes y distribuidos en parches conforme realizan diferentes comportamientos. Nosotros estudiamos la dinámica de la abundancia diurna de gaviotas Larus glaucescens en un parche de hábitat dedicado al descanso en el estrecho de Juan de Fuca, Washington. Construimos tres modelos basados en ecuaciones diferenciales como hipótesis alternativas y después empleamos técnicas de selección de modelos para escoger el que mejor describía el sistema. Validamos este modelo usando datos independientes, hicimos predicciones a priori a partir del modelo y realizamos una prueba de dichas predicciones en el campo. Algunos patrones en la dinámica de la abundancia de las gaviotas que estaban descansando fueron claros, aunque algunos individuos se movieron hacia adentro y hacia afuera del área de descanso de forma más o menos continua a través del día. Los patrones temporales en el comportamiento de descanso agregado fueron predichos por tres factores ambientales: el día del año, la altura de la marea y la elevación del sol. Este resultado es importante por varias razones: (1) reduce el complicado comportamiento de agregación de los vertebrados a una simple ecuación matemática, (2) da un ejemplo de un sistema de campo en el que la abundancia de los animales está determinada en buena parte por fuerzas exógenas de pocas dimensiones y (3) provee un ejemplo de una predicción cuantitativa exacta de números de animales en el campo. Desde el punto de vista de la biología de la conservación y el manejo de los recursos, este resultado es importante debido a la imperiosa necesidad de explicar y predecir la abundancia de los organismos en el tiempo y en el espacio.
    No preview · Article · Jan 2009 · The Auk
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    ABSTRACT: Development of locomotor activity is crucial in tetrapods. In birds, this development leads to different functions for hindlimbs and forelimbs. The emergence of walking and flying as very different complex behavior patterns only weeks after hatching provides an interesting case study in animal development. We measured the diaphyseal lengths and midshaft diameters of three wing bones (humerus, ulna, and carpometacarpus) and three leg bones (femur, tibiotarsus, and tarsometatarsus) of 79 juvenile (ages 0-42 days) and 13 adult glaucous-winged gulls (Larus glaucescens), a semiprecocial species. From a suite of nine alternative mathematical models, we used information-theoretic criteria to determine the best model(s) for length and diameter of each bone as a function of age; that is, we determined the model(s) that obtained the best tradeoff between the minimized sum of squared residuals and the number of parameters used to fit the model. The Janoschek and Holling III models best described bone growth, with at least one of these models yielding an R(2) > or = 0.94 for every dimension except tarsometatarsus diameter (R(2) = 0.87). We used the best growth models to construct accurate allometric comparisons of the bones. Early maximal absolute growth rates characterize the humerus, femur, and tarsometatarsus, bones that assume adult-type support functions relatively early during juvenile development. Leg bone lengths exhibit more rapid but less sustained relative growth than wing bone lengths. Wing bone diameters are initially smaller than leg bone diameters, although this relationship is reversed by fledging. Wing bones and the femur approach adult length by fledging but continue to increase in diameter past fledging; the tibiotarsus and tarsometatarsus approach both adult length and diameter by fledging. In short, the pattern of bone growth in this semiprecocial species reflects the changing behavioral needs of the developing organism.
    Full-text · Article · Jan 2009 · Journal of Morphology
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    ABSTRACT: The reaction of 2,4-bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide (Woollins' Reagent, WR) with phenylalkylcyanamides (RR'NC[triple bond, length as m-dash]N, R = PhCH2CH2, R' = CH3 and R = PhCH2CH2CH2, R' = H) in refluxing toluene led to novel heterocyclic selenazadiphospholaminediselenides and (43% and 42% yields), the latter being hydrolyzed to the unusual zwitterionic carbamidoyl(phenyl)phosphinodiselenoic acids and in excellent yields (96% and 98%).
    Full-text · Article · Dec 2008 · Dalton Transactions
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    ABSTRACT: We constructed differential equation models for the diurnal abundance and distribution of breeding glaucous-winged gulls (Larus glaucescens) as they moved among nesting and non-nesting habitat patches. We used time scale techniques to reduce the differential equations to algebraic equations and connected the models to field data. The models explained the data as a function of abiotic environmental variables with R(2 )=0.57. A primary goal of this study is to demonstrate the utility of a methodology that can be used by ecologists and wildlife managers to understand and predict daily activity patterns in breeding seabirds.
    Full-text · Article · Nov 2008 · Mathematical biosciences and engineering: MBE
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    ABSTRACT: Searching for gravitational waves triggered by electromagnetic astronomical observations has several benefits: prior information about the source location enhances detection efficiency, and the use of time coincidence implies analysis of only a small stretch of data which allows sophisticated analysis with high computational costs. During postprocessing, knowledge about the source enables accurate reconstruction of the source parameters, leading to an astrophysical interpretation. In this paper, we present a triggered search pipeline called RIDGE and we demonstrate the search for gravitational waves from Sco X-1, in which X-ray bursts occur frequently, using simulated data. In the analysis, we consider the optimum network combination for Sco X-1.
    Full-text · Article · Jul 2008 · Journal of Physics Conference Series
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    ABSTRACT: Haematological responses (cellular alterations) induced 6 months post-treatment by three toxic metals, arsenic, cadmium and mercury, are reported. Treatment was at early stages of rainbow trout, Oncorhynchus mykiss, development. Different blood parameters (haematocrit level, red cells/mm3, white cells/mm3 red/white cell ratio and the white blood cell differential count) were examined in association with a histological examination. Significant differences were observed in the total number of leucocytes and the number of lymphocytes between the lesion-bearing fish of the arsenic and cadmium group and the healthy fish. Subsequently, the blood films showed atypical lymphocytes.
    No preview · Article · Jul 2008 · Journal of Applied Ichthyology
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    ABSTRACT: This paper examines a paradox in corporate audit history that threatens the credibility of the current audit as a means of protecting stakeholders from corrupt senior managers. Using a historical analysis of legal cases of fraudulent reporting and subsequent public accountancy responses, the study reveals the paradox of a corporate auditor denying or limiting responsibility to detect material accounting misstatement (MAM) facilitated by dominant senior managers (DSM), while relying on the honesty of senior managers. The primary finding of the legal case analysis is the persistent presence of a DSM or team of DSM in the context of various contributing features, and the creation by Victorian lawyers of a model of excuses for the corporate auditor. The primary finding from the responses of public accountants is, within the context of the model of excuses and the assumption of managerial honesty, continuous denial, or limitation of auditor responsibility for detecting MAM facilitated by DSM. The consequence of this history is that DSM intent on MAM currently face corporate auditors generally untrained to assess the audit risk of managerial domination facilitating MAM. The paper's single recommendation is that corporate auditors be educated and trained to assess the audit risk associated with DSM facilitating MAM. The paper's contribution to corporate auditing is its use of historical analysis to bring together previously known but relatively disparate matters into a coherent whole that signals a fatal flaw in existing practice.
    No preview · Article · Jul 2008 · Critical Perspectives on Accounting
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    ABSTRACT: The melt-out of material contained within englacial thrust planes has been proposed to result in the formation of stacked moraine sequences with characteristic proximal rectilinear slopes. This model has been applied to explain the formation of Scottish Younger Dryas ice-marginal (‘hummocky’) moraines on the basis of these morphological characteristics. However, no sedimentological data exist to support this proposal. This article reviews hitherto proposed models of ‘hummocky’ moraine formation and presents detailed geomorphological and sedimentological results from the NW Scottish Highlands with the aims of reconstructing the dynamics of Younger Dryas glaciers and of testing the applicability of the englacial thrusting model. Exposures demonstrate that moraines represent terrestrial ice-contact fans throughout, with a variety of postdepositional deformation structures being identified in most cases, indicating that glacier retreat was incremental and oscillatory; proximal rectilinear slopes are interpreted as ice-contact faces formed after ice support was withdrawn during retreat. This evidence strongly suggests a temperate glacier regime and short glacier response times similar to those in present-day SW Norway or Iceland. It contradicts the thrusting model and the proposal that Svalbard might form a suitable analogue for Younger Dryas moraines in Scotland.
    No preview · Article · Jun 2008 · Boreas

  • No preview · Article · Jun 2008 · Zoological Journal of the Linnean Society
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    ABSTRACT: Protection Island National Wildlife Refuge, WA, is home to the majority of breeding seabirds and harbor seals found in the Puget Sound/San Juan Island area. The island consists of a high central plateau flanked by bluffs on the north and south and by low points on the southwest and east. We analyzed the physical and vegetational changes in Protection Island from the 1860s to 1999, an interval spanning an early period of agricultural use followed by intensive subdivision into building lots and then conversion to a refuge. During that time span Kanem Point on the southwest had shortened and Violet Point on the east had lengthened. The tall northwest bluffs, which experienced rapid erosion early last century, had steepened and stabilized. Little change had occurred on the northeast and southern bluffs or on the bluffs over the points where many seabirds nest. On the upper plateau, forested areas had shrunk sharply due to fires and lot development but were recovering. Dunes had migrated to the northeast and stabilized. Introduced species dominated the grasslands on the upper plateau. By contrast, native species continued to dominate Violet Point. Native dune grass, however, was expanding on Violet Point and tended to exclude most other species. Richness, percent cover, and diversity of introduced species on Violet Point were significantly lower than on the upper plateau, while richness and percent cover of native species were higher. Continued prevalence of native species on the point may be a result of a plant community adapted to the low, rocky substrate and frequent disturbance by nesting gulls.
    Full-text · Article · Jun 2008 · Northwest Science
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    ABSTRACT: We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first nine months of the fifth science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). These limits are based on two searches. In the first we assume that the gravitational wave emission follows the observed radio timing, giving an upper limit on gravitational wave emission that beats indirect limits inferred from the spin-down and braking index of the pulsar and the energetics of the nebula. In the second we allow for a small mismatch between the gravitational and radio signal frequencies and interpret our results in the context of two possible gravitational wave emission mechanisms.
    Full-text · Article · May 2008 · The Astrophysical Journal

  • No preview · Article · May 2008 · Midwest Studies in Philosophy
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    ABSTRACT: An L-shaped auditory intemeuron (LI) has been recorded from extracellularly and intracellularly, and identified morphologically (by Lucifer yellow or cobalt injection) in the prothoracic ganglion of mature female Acheta domesticus. The morphology of the LI is very similar to ascending, prothoracic acoustic interneurons that are most sensitive to higher carrier frequencies in both A. domesticus and other gryllid species. Its terminations in the brain are similar to ascending acoustic interneurons found in other gryllids. The LI neuron is most sensitive to 4–5 kHz model calling songs (CSs), the main carrier frequency of the natural call. Thresholds to high frequencies (8–15 kHz) are 15–20 dB higher. Increasing CS intensities of up to 15 dB above threshold at 4–5 kHz result in increased firing rates by the LI. More than 15 dB increase in intensity causes saturation with little increase in spiking rate until the intensity surpasses 80 dB. In response to 70 dB or higher stimulus intensities, the LI responds to the second and third CS syllables with one or two spikes, pauses, and then produces a burst of nerve impulses with the same or greater latency than for lower intensity stimuli. In response to CS syllables of changing duration (10–30 ms) this neuron responds with a rather constant duration burst of impulses. Syllable periods of the CS stimuli were accurately encoded by the LI. Progressively stronger injection of hyperpolarizing current reduces, and ultimately stops spiking of the LI in response to CS stimuli. More intense stimulation with reduced hyperpolarization shows an initial spike, pause and burst of spikes. Intracellular recording from axonal regions of the neuron shows large spikes, small EPSPs and a developing hyperpolarization through the response to a CS chirp. Inhibitory input to the LI is demonstrated at 4.5, 8 and 16 kHz. This probably explains the specialized response characteristics of the LI which enhanced its encoding of CS syllable period.
    No preview · Article · Mar 2008 · Physiological Entomology
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    ABSTRACT: The scototactic responses of adult female Acheta domesticus L. were tested toward various shaped targets in an orientation arena and on a compensatory treadmill. In an arena, crickets oriented toward dark targets (positive scototaxis) if they had horizontal visual angles ≥30d̀, and if the vertical dimensions of the target was ≤ its horizontal dimension. Unattractive targets did not result in negative scototaxis but caused crickets to orient randomly with no net directionality. When complex targets were composed of two or more simple rectangular targets which had been previously defined as attractive or unattractive, intermediate responses were obtained. Crickets oriented less toward complex targets than toward simple attractive targets, but oriented more than toward simple unattractive targets. The responses of a female cricket toward an attractive target can be modified by the presence of a chemical signal emitted by previously tested females. When the signal is present females are less likely to orient toward a target that would otherwise be very attractive. This effect was not as great when the females being tested were taken directly from densely populated colonies. When running on a compensatory treadmill, female crickets exhibit scototactic tendencies similar to those displayed in the arena. When tested on the treadmill over long periods, the amount of time spent orienting toward an attractive target increased.
    No preview · Article · Mar 2008 · Physiological Entomology
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    ABSTRACT: Female Acheta domesticus L. were tested for tracking model calling songs with different syllable periods on the Kramer treadmill in the dark, under homogenous light, and in the presence of a visually attractive target (black square) positioned either perpendicular to or in front of the invisible acoustical target. The females exhibited tracking of the two targets by different walking modes.
    No preview · Article · Mar 2008 · Physiological Entomology
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    ABSTRACT: We examined local public health agencies' involvement in community illicit drug policy advocacy and provision related to youths to determine the extent to which public health agencies were involved in local drug policy activities and could potentially provide an infrastructure for policy alternatives. We conducted telephone interviews from 1999 to 2003 with 1793 US public health agencies in 804 communities surrounding schools participating in the Monitoring the Future study. Respondents reported public health agency planning, priorities, and involvement in alternative drug policy advocacy and prevention activities. We examined results for variance by site sociodemographic characteristics. Most students lived where public health agencies provided resources for community- and school-based drug use prevention. More than one third resided where public health agencies advocated for drug policy alternatives and more than one quarter where public health agencies were involved in juvenile drug court programs. Such activities were significantly higher in urban communities, in the West, and in sites where the proportion of African Americans was above the national average. Although local public health agencies could increase participation levels in drug policy alternatives, current involvement suggests that agencies may provide a base for supporting the development of public health alternatives to deterrence-based drug policies. Such a base may be more likely in communities with the highest need for such policies and services.
    Full-text · Article · Mar 2008 · American Journal of Public Health
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    Preview · Article · Feb 2008 · Beilstein Journal of Organic Chemistry
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    ABSTRACT: We show that under the Black–Scholes assumption the price of an arithmetic average Asian call option with fixed strike increases with the level of volatility. This statement is not trivial to prove and for other models in general wrong. In fact we demonstrate that in a simple binomial model no such relationship holds. Under the Black–Scholes assumption however, we give a proof based on the maximum principle for parabolic partial differential equations. Furthermore we show that an increase in the length of duration over which the average is sampled also increases the price of an arithmetic average Asian call option, if the discounting effect is taken out. To show this, we use the result on volatility and the fact that a reparametrization in time corresponds to a change in volatility in the Black–Scholes model. Both results are extremely important for the risk management and risk assessment of portfolios that include Asian options.
    Full-text · Article · Jan 2008 · SSRN Electronic Journal
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    ABSTRACT: This research focused on the use of writing to increase reflection and problem solving in the clinical setting. Two groups of associate degree students provided clinical care and maintained journals, answering a series of focused questions. One group of students worked as individuals in the clinical setting; the other consisted of students working in pairs. There were significant differences between levels of reflection of students who worked in pairs and those who were not paired. Three major themes were found in students' journals: emotions, connections between theory and practice, and learning.
    No preview · Article · Jan 2008 · Nursing education perspectives
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    ABSTRACT: Data from the LIGO Livingston interferometer and the ALLEGRO resonant-bar detector, taken during LIGO’s fourth science run, were examined for cross correlations indicative of a stochastic gravitational-wave background in the frequency range 850–950 Hz, with most of the sensitivity arising between 905 and 925 Hz. ALLEGRO was operated in three different orientations during the experiment to modulate the relative sign of gravitational-wave and environmental correlations. No statistically significant correlations were seen in any of the orientations, and the results were used to set a Bayesian 90% confidence level upper limit of Ωgw(f)≤1.02, which corresponds to a gravitational-wave strain at 915 Hz of 1.5×10-23 Hz-1/2. In the traditional units of h1002Ωgw(f), this is a limit of 0.53, 2 orders of magnitude better than the previous direct limit at these frequencies. The method was also validated with successful extraction of simulated signals injected in hardware and software.
    Full-text · Article · Jan 2008 · Physical Review D
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    ABSTRACT: The production of dijets in diffractive deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 61 pb(-1). The dijet cross section has been measured for virtualities of the exchanged virtual photon, 5 < Q(2) < 100 GeV(2), and gamma* p centre-of-mass energies, 100 < W < 250 GeV. The jets, identifed using the inclusive k(T) algorithm in the gamma*p frame, were required to have a transverse energy E(T)(*),(jet) > 4GeV and the jet with the highest transverse energy was required to have E(T)(*),jet > 5 GeV. All jets were required to be in the pseudorapidity range -3.5 < eta(*)(jet) < 0. The differential cross sections are compared to leading-order predictions and next-to-leading-order QCD calculations based on recent diffractive parton densities extracted from inclusive diffractive deep inelastic scattering data.
    Full-text · Article · Dec 2007 · European Physical Journal C
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    ABSTRACT: The fourth science run of the LIGO and GEO 600 gravitational-wave detectors, carried out in early 2005, collected data with significantly lower noise than previous science runs. We report on a search for short-duration gravitational-wave bursts with arbitrary waveform in the 64–1600 Hz frequency range appearing in all three LIGO interferometers. Signal consistency tests, data quality cuts and auxiliary-channel vetoes are applied to reduce the rate of spurious triggers. No gravitational-wave signals are detected in 15.5 days of live observation time; we set a frequentist upper limit of 0.15 day−1 (at 90% confidence level) on the rate of bursts with large enough amplitudes to be detected reliably. The amplitude sensitivity of the search, characterized using Monte Carlo simulations, is several times better than that of previous searches. We also provide rough estimates of the distances at which representative supernova and binary black hole merger signals could be detected with 50% efficiency by this analysis.
    Full-text · Article · Nov 2007 · Classical and Quantum Gravity
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    ABSTRACT: Two of ABET's engineering program outcomes are that graduates of engineering programs possess an ability to communicate effectively and an ability to function on multi-disciplinary teams. It has been observed with concern that entrants to engineering programs are inadequately prepared with respect to communication skills in oral and written communication, report writing, technical writing, lecture notes taking, math skills, inter alia. This paper demonstrates how courses in the engineering program, namely, introduction to engineering, and engineering graphics can be used to develop skills in technical writing, oral communication, team building, creativity, analysis, synthesis; in the overall engineering design process. Real life projects were used. Customer requests were made and briefs obtained for projects. Course evaluation tools were used to assess student learning outcomes. Feedback sessions were held and outcomes and lessons learned were documented towards ABET accreditation and follow up studies.
    Full-text · Conference Paper · Nov 2007
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    ABSTRACT: Physics Enterprises, Andrews University, was desirous of documenting their designs and updating the equipment manuals and designs. No engineering drawings existed for the equipment they develop, manufacture and sell internationally. For the course engineering graphics, it was desired to have a class project in a real life experience in technical briefing, technical writing, presentation and team building. The two needs perfectly matched. This paper demonstrates how engineering graphics can be used to develop skills and team building in undergraduate freshmen and between university departments. A mixed freshman class was organized into a team and subgroups and using freehand sketching and CAD software, through a process of reverse engineering, successfully developed final engineering drawings. The results were presented to a new engineering graphics class by the previous class. Valuable lessons were learnt in instructor and client availability, balance of work and significance of real life experience.
    Preview · Conference Paper · Nov 2007
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    ABSTRACT: Extracting quantities, such as the propagation factor or the characteristic impedance of a transmission line based on measured S -parameters, can be more involved than expected. Experience teaches that even if the S -parameter measurements look smooth and are of good quality, the derived quantities can contain large spikes that tend to grow when connection imperfections are present. In this paper, the presence of the peaks is shown in practical measurements, a possible explanation for their presence is provided, and a sensitive indicator (the image parameters) for the imperfections is proposed.
    Preview · Article · Nov 2007 · IEEE Transactions on Instrumentation and Measurement
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    ABSTRACT: Forward jet cross sections have been measured in neutral current deep inelastic scattering at low Bjorken-x with the ZEUS detector at HERA using an integrated luminosity of 81.8 pb(-1). Measurements are presented for inclusive forward jets as well as for forward jets accompanied by a dijet system. The explored phase space, with jet pseudorapidity up to 4.3 is expected to be particularly sensitive to the dynamics of QCD parton evolution at low x. The measurements are compared to fixed-order QCD calculations and to leading-order parton-shower Monte Carlo models.
    No preview · Article · Nov 2007 · European Physical Journal C
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    ABSTRACT: We present upper limits on the gravitational wave emission from 78 radio pulsars based on data from the third and fourth science runs of the LIGO and GEO 600 gravitational wave detectors. The data from both runs have been combined coherently to maximize sensitivity. For the first time, pulsars within binary (or multiple) systems have been included in the search by taking into account the signal modulation due to their orbits. Our upper limits are therefore the first measured for 56 of these pulsars. For the remaining 22, our results improve on previous upper limits by up to a factor of 10. For example, our tightest upper limi
    Full-text · Article · Sep 2007 · Physical Review D
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    ABSTRACT: This study was designed to investigate the frequency with which school-based speech-language pathologists (SLPs) used recommended practices when assessing the language skills of bilingual students. The study also investigated the frequency with which SLPs used formal, standardized tests versus informal, alternative procedures with this population. A total of 596 surveys were mailed out to school-based SLPs in the state of Michigan who were members of the Michigan Speech, Language, and Hearing Association (MSHA) during the 2003-2004 academic year. Of the 409 usable surveys that were returned, 130 respondents indicated being involved in assessing bilingual children and comprised the sample used in this study. Results indicated that SLPs used formal, standardized English tests more frequently than informal assessment procedures when assessing bilingual students. Further in-depth analyses of SLPs' responses indicated that neither factors related to their years of experience or factors related to their academic preparation were significantly related to their use of recommended assessment practices. However, significant differences in use were noted based on respondents' employment settings. This study underscores the need for academic training programs and professional organizations to intentionally disseminate information regarding the expediency of alternative testing procedures. Implications for the adequate nonbiased assessment of bilingual children are discussed.
    No preview · Article · Aug 2007 · Language Speech and Hearing Services in Schools
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    ABSTRACT: In the United States, state governments legally authorize outpatient substance abuse treatment programs. In some states, programs are certified or accredited (ideal standards). Other states license programs (minimal standards). Additionally, some states authorize programs through "deemed status", which is afforded to programs attaining accreditation from a national accrediting body. Primary legal research and the National Survey of Substance Abuse Treatment Services' (N-SSATS) data were used to examine the relationships between state authorization type (certification/accreditation vs licensure with and without deemed status) and outpatient treatment program practices. Programs in certification/accreditation (vs licensure) states had significantly higher odds of offering wrap-around and continuing care/after care services associated with better long-term treatment outcome. Programs in states that allowed for certification/accreditation with deemed status had significantly lower odds of infectious disease testing, but higher odds of providing group and family counseling. Results suggest that state authorization type may impact services offered by outpatient treatment programs.
    No preview · Article · Aug 2007 · The Journal of Behavioral Health Services & Research
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    ABSTRACT: A number of recent studies examining historical experiences with deflation have called into question the widely-held view that maintains deflation is economically harmful. These studies contend that a broad, historical perspective reveals a more nuanced view of deflation, one that requires taking seriously both malign and benign deflation. This paper builds on these findings by taking an in-depth look at the U.S. experience with deflation during the postbellum period and considers whether it supports the claim that deflation can be benign. This paper also considers the lessons of this deflation experience for monetary policy today.
    Preview · Article · Aug 2007 · The North American Journal of Economics and Finance
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    ABSTRACT: Silver nanoparticles in aqueous suspensions were synthesized by reduction of silver oxide by H2 following recently published procedures.12 These particles contain no foreign stabilizers or any ions other than those from silver and water. The particles were characterized by their UV−vis absorption spectra, by transmission electron microscopy, by dynamic light-scattering−zeta potential determination, and by the pH dependence of the potential. The nanoparticles are stabilized by adsorption of hydroxide anions at the particles surface. Their zeta potential is 35 mV at pH 9; it is pH dependent and the point of zero charge is near neutral. The negative potential, the hydrophilic surface that is created by the adsorbed hydroxide ions, which resembles an oxide interface, and the low ionic strength of the solution due to the small salt concentrations in this synthetic approach all contribute to the unusual stability of the colloidal suspension. The amount of molecular hydrogen formed was determined following γ-irradiation of the silver suspensions in the presence of 2-propanol and acetone. In these suspensions, all of the radiolytically generated radicals are converted to reducing radicals capable of reducing water to H2. At low doses, however, the amount is very small but after a “conditioning” period the yield substantially increases. The conditioning stage is explored in detail, and it is shown that the main reaction responsible for the conditioning is reduction of residual silver ions in the solution. The steady-state concentration of residual Ag+ ions that remains in the solution is determined by the relative rates of silver oxide dissolution and silver ions reduction during the synthesis. Analysis of the chemical composition of the suspensions at the end of the synthesis also indicates that a few percent of Ag+ ions remain unreduced. Most of the unreduced ions are free in the bulk solution while a minority adsorbs at the particle surface. Once the conditioning stage is complete, essentially all reducing radicals generated by the irradiation can catalytically produce hydrogen. For the presently studied silver particles of 30 nm, competition between radical−radical recombination and hydrogen evolution is suppressed at >2 mM silver concentrations. Little is to be gained by increasing the catalyst concentration above this level.
    No preview · Article · Jul 2007 · The Journal of Physical Chemistry C
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    ABSTRACT: Bose–Einstein correlations of charged and neutral kaons have been measured in deep inelastic scattering with an integrated luminosity of using the ZEUS detector at HERA. The two-particle correlation function was studied as a function of the four-momentum difference of the kaon pairs, , assuming a Gaussian shape for the particle source. The values of the radius of the production volume, r, and of the correlation strength, λ, were obtained for both neutral and charged kaons. The radii for charged and neutral kaons are similar and are consistent with those obtained at LEP.
    Full-text · Article · Jul 2007 · Physics Letters B
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    ABSTRACT: We demonstrate that photoluminescence (PL) quantum yield and PL lifetime of fac-tris(2-phenylpyridyl) iridium(III) [Ir(ppy)<sub>3</sub>]-cored dendrimers in neat film and dispersed into a 4,4'-bis(N-carbazolyl)biphenyl host can be significantly improved by a simple adjustment of the solution preparation. Quenching of the PL in these materials is due to an energy transfer of the triplet excitons to less-emissive sites and can be reduced by blending the phosphorescent molecules into a suitable wide energy gap host or by increasing the number of attached dendrons. We show here that the concentration of these quenchers can also be controlled by changing the time spent by the dendrimer solution under illumination prior to spin-coating. By optimizing the film preparation procedure, the external efficiency of devices made from neat dendrimer films was increased from 2% to 10%
    No preview · Article · Jul 2007 · Journal of Display Technology
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    ABSTRACT: Charm production in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb-1. Charm has been tagged by reconstructing D*+, D0, D+ and D+s (+ c.c.) charm mesons. The charm hadrons were measured in the kinematic range pT (D* +,D 0,D+) > 3GeV, pT (D+s ) > 2GeV and |η(D)| < 1.6 for 1.5 < Q2 < 1000GeV2 and 0.02 < y < 0.7. The production cross sections were used to extract charm fragmentation ratios and the fraction of c quarks hadronising into a particular charm meson in the kinematic range considered. The cross sections were compared to the predictions of next-to-leading-order QCD, and extrapolated to the full kinematic region in pT (D) and η(D) in order to determine the open-charm contribution, Fcc2 (x,Q2), to the proton structure function F2.
    Full-text · Article · Jul 2007 · Journal of High Energy Physics
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    ABSTRACT: The number of botany students, botany classes, botany departments in universities and botanists attending conventions has been declining over many years in North America. This is part of a general trend throughout the field of organismal biology, not just botany. The history leading up to the situation today in North America, is discussed and reasons are given for this trend over the last century of time. Seven ways to keep botany a viable occupation are discussed otherwise botany, in the 21st century, may go the way of the dinosaur.
    No preview · Article · Jul 2007 · South African Journal of Botany
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    ABSTRACT: The distribution of the azimuthal angle of charged and neutral hadrons relative to the lepton plane has been studied for neutral current deep inelastic ep scattering using an integrated luminosity of 45pb-1 taken with the ZEUS detector. The kinematic range is 100<Q2<8000GeV2, 0.2<y<0.8 and 0.01<x<0.1 where Q2 is the virtuality of the exchanged boson, y is the inelasticity and x is the Bjorken variable. The measurements were made in the hadronic centre-of-mass system. The analysis exploits the energy-flow method, which allows the measurement to be made over a larger range of pseudorapidity compared to previous results. The dependence of the moments of the azimuthal distributions on the pseudorapidity and minimum transverse energy of the final-state hadrons are presented. Although the predictions from next-to-leading-order QCD describe the data better than do the Monte Carlo models incorporating leading-logarithm parton showers, they still fail to describe the magnitude of the asymmetries. This suggests that higher-order calculations may be necessary to describe these data.
    Full-text · Article · Jun 2007 · European Physical Journal C
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    ABSTRACT: Inclusive dijet and trijet production in deep inelastic ep scattering has been measured for 10<Q2<100 GeV2 and low Bjorken x, 10−4<xBj<10−2. The data were taken at the HERA ep collider with centre-of-mass energy using the ZEUS detector and correspond to an integrated luminosity of 82 pb−1. Jets were identified in the hadronic centre-of-mass (HCM) frame using the kT cluster algorithm in the longitudinally invariant inclusive mode. Measurements of dijet and trijet differential cross sections are presented as functions of Q2, xBj, jet transverse energy, and jet pseudorapidity. As a further examination of low-xBj dynamics, multi-differential cross sections as functions of the jet correlations in transverse momenta, azimuthal angles, and pseudorapidity are also presented. Calculations at generally describe the trijet data well and improve the description of the dijet data compared to the calculation at .
    Full-text · Article · Jun 2007 · Nuclear Physics B
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    ABSTRACT: Faraday rotators using permanently magnetized ferrite materials are used to make quasi-optical isolators and circulators at millimeter wave and sub-millimeter wave frequencies that have far higher performance than their waveguide equivalents. This paper demonstrates state-of-the-art performance for four-port quasi-optical circulators with 60-dB isolation, 0.2-dB insertion loss, and better than 80-dB return loss for devices centered at 94 GHz. A method is presented for the accurate characterization of the complex permeability and permittivity of permanently magnetized ferrites via a series of frequency and polarization dependent transmission and reflection measurements. The dielectric and magnetic parameters for the sample are determined by fitting theoretical curves to the measured data. These fitted parameters are then used in a model for a complete quasi-optical Faraday rotator, including matching layers, allowing the accurate design and fabrication of these devices for any specific operational frequency band in the millimeter wave and sub-millimeter wave regime. Examples are given showing typical results and demonstrating how temperature cycling can significantly improve the temperature stability of these devices, while allowing fine tuning of the center frequency. We also indicate the performance possible at higher frequencies to above 1 THz and outline performance of truly planar isolators where lossy polarizer material is built into the Faraday rotator matching structure
    Preview · Article · Jun 2007 · IEEE Transactions on Microwave Theory and Techniques
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    ABSTRACT: Australian youth engage in behaviour that threatens their health and wellbeing. National surveys report that about a third of young Australians have tried an illicit drug. High rates of substance use and risky sexual behaviour among young Australians suggest that effective prevention efforts based on empirical evidence need to be expanded. Church-associated organisations are an untapped resource that could be used to improve the health and welfare of young people. We describe eight evidence-based elements to consider in designing strategies to prevent high-risk behaviour in young people.
    Full-text · Article · Jun 2007 · The Medical journal of Australia
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    ABSTRACT: Age relations for assembly of Gondwana and Pangea indicate that the timing of collisional orogenesis between amalgamating continental bodies was synchronous with subduction initiation and contractional orogenesis within accretionary orogens located along the margins of these supercontinents. Final assembly of Gondwana occurred between c.570 and 510 Ma, amalgamating the various components of East and West Gondwana. This was coeval with a switch from passive margin sedimentation to convergent margin activity along the Pacific margin of the supercontinent. Timing of subduction initiation along the Pacific margin ranges from 580 to 550 Ma as evidenced by the first appearance of arc derived detrital zircons in the upper Byrd Group sediments and the oldest supra-subduction zone plutons along the Antarctic segment of the margin. A phase of extension marked by supra-subduction zone ophiolite generation at 535–520 Ma is preserved in greenstone successions in eastern Australia and overlaps the onset of Ross–Delamerian contractional orogenesis between 520 and 490 Ma, inboard of the plate margin that coincides with the cessation of collisional orogenesis between the amalgamating blocks of Gondwana. Supra-subduction zone igneous activity was continuous throughout this period indicating that subduction was ongoing.
    Full-text · Article · Jun 2007 · Earth-Science Reviews
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    ABSTRACT: The production of D*±(2010) mesons in e±p scattering in the range of exchanged photon virtuality 0.05Q20.7 GeV2 has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb−1. The decay channels D*+→D0π+ with D0→K−π+ and corresponding antiparticle decay were used to identify D* mesons and the ZEUS beampipe calorimeter was used to identify the scattered electron. Differential D* cross sections as functions of Q2, inelasticity, y, transverse momentum of the D* meson, pT(D*), and pseudorapidity of the D* meson, η(D*), have been measured in the kinematic region 0.02y0.85, 1.5pT(D*)9.0 GeV and |η(D*)|1.5. The measured differential cross sections are in agreement with two different NLO QCD calculations. The cross sections are also compared to previous ZEUS measurements in the photoproduction and DIS regimes.
    Full-text · Article · May 2007 · Physics Letters B
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    ABSTRACT: The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300–318 GeV using an integrated luminosity of 120 pb−1. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3<pT/M<0.7. The particle rates have been extracted and interpreted in terms of the coalescence model. The (anti)deuteron production yield is smaller than the (anti)proton yield by approximately three orders of magnitude, consistent with the world measurements.
    Full-text · Article · May 2007 · Nuclear Physics B
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    ABSTRACT: Differential inclusive-jet cross sections have been measured for different jet radii in neutral current deep inelastic ep scattering for boson virtualities Q2>125 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 81.7 pb−1. Jets were identified in the Breit frame using the kT cluster algorithm in the longitudinally inclusive mode for different values of the jet radius R. Differential cross sections are presented as functions of Q2 and the jet transverse energy, . The dependence on R of the inclusive-jet cross section has been measured for Q2>125 and 500 GeV2 and found to be linear with R in the range studied. Next-to-leading-order QCD calculations give a good description of the measurements for 0.5⩽R⩽1. A value of αs(MZ) has been extracted from the measurements of the inclusive-jet cross section dσ/dQ2 with R=1 for Q2>500 GeV2: . The variation of αs with is in a good agreement with the running of αs as predicted by QCD.
    Full-text · Article · May 2007 · Physics Letters B
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    ABSTRACT: SYNOPSIS. The life cycle of Eimeria ferrisi is described from experimentally infected Mus musculus. The prepatent period was 3 days and the patent period was 3–4 days. The endogenous stages were found only in the cecum and colon. Three generations of schizonts were found. Mature 1st-generation schizonts first seen 24 hr postinoculation (PI) measured 10.9 (7–14) × 10.2 (6–13) μm and had 9.6 (7–14) merozoites. Some 2nd-generation schizonts had uninucleate merozoites and others had multinucleate merozoites. The former were first seen in small numbers 36 hr PI and were most abundant 48 hr PI. They measured 9.6 (5–13) × 7.9 (6–12) μm and had 18 (6–25) merozoites. Schizonts with multinucleate merozoites were seen 72 hr PI. Mature 3rd-generation schizonts were seen 72 hr PI. They measured 14.0 (12–18) × 11-0 (9–13) μm and had 12.5 (5–16) merozoites. Macrogamonts were first seen in 72 hr sections. Each young macrogamont had a large nucleus with a prominent nucleolus. Only one type of cytoplasmic granule appeared to be involved in the formation of the oocyst wall. Mature macrogamonts were 11.0 (5–14) × 10.0 (6–13) μm. Crescent-shaped bodies were observed in the parasitophorous vacuole of trophozoites and young macrogamonts. Early microgamonts were first recognized at 96 hr by the presence of darkly stained and irregularly shaped nuclei. Usually, mature microgametes were arranged in long, narrow whorls at the periphery of the microgamont or in whorls at the surface of 2–5 compartments.
    No preview · Article · Apr 2007 · Journal of Eukaryotic Microbiology
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    ABSTRACT: We have searched for gravitational waves (GWs) associated with the SGR 1806-20 hyperflare of 27 December 2004. This event, originating from a Galactic neutron star, displayed exceptional energetics. Recent investigations of the x-ray light curve’s pulsating tail revealed the presence of quasiperiodic oscillations (QPOs) in the 30–2000 Hz frequency range, most of which coincides with the bandwidth of the LIGO detectors. These QPOs, with well-characterized frequencies, can plausibly be attributed to seismic modes of the neutron star which could emit GWs. Our search targeted potential quasimonochromatic GWs lasting for tens of seconds and emitted at the QPO frequencies. We have observed no candidate signals above a predetermined threshold, and our lowest upper limit was set by the 92.5 Hz QPO observed in the interval from 150 s to 260 s after the start of the flare. This bound corresponds to a (90% confidence) root-sum-squared amplitude hrss-det⁡90%=4.5×10-22 strain Hz-1/2 on the GW waveform strength in the detectable polarization state reaching our Hanford (WA) 4 km detector. We illustrate the astrophysical significance of the result via an estimated characteristic energy in GW emission that we would expect to be able to detect. The above result corresponds to 7.7×1046 erg (=4.3×10-8 M⊙c2), which is of the same order as the total (isotropic) energy emitted in the electromagnetic spectrum. This result provides a means to probe the energy reservoir of the source with the best upper limit on the GW waveform strength published and represents the first broadband asteroseismology measurement using a GW detector.
    Full-text · Article · Apr 2007 · Physical Review D
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    ABSTRACT: The photoproduction of dijet events, where the two jets with the highest transverse energy are separated by a large gap in pseudorapidity, have been studied with the ZEUS detector using an integrated luminosity of 39 pb-1. Rapidity-gap events are defined in terms of the energy flow between the jets, such that the total summed transverse energy in this region is less than some value ET CUT. The data show a clear excess over the predictions of standard photoproduction models. This is interpreted as evidence for a strongly interacting exchange of a color-singlet object. Monte Carlo models which include such a color-singlet exchange are able to describe the data.
    Full-text · Article · Apr 2007 · European Physical Journal C
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    ABSTRACT: A search for stop production in R-parity-violating supersymmetry has been performed in e+p interactions with the ZEUS detector at HERA, using an integrated luminosity of 65pb-1. At HERA, the R-parity-violating coupling λ’ allows resonant squark production, e+d®[(q)\tilde]e^+d\to\tilde{q}. Since the lowest-mass squark state in most supersymmetry models is the light stop, [(t)\tilde]\tilde{t}, this search concentrated on production of [(t)\tilde]\tilde{t}, followed either by a direct R-parity-violating decay, or by the gauge decay to b[(c)\tilde]+1b\tilde{\chi}^+_{1}. No evidence for stop production was found and limits were set on λ’131 as a function of the stop mass in the framework of the minimal supersymmetric standard model. The results have also been interpreted in terms of constraints on the parameters of the minimal supergravity model.
    Full-text · Article · Apr 2007 · European Physical Journal C
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    ABSTRACT: The production of beauty quarks with a D*±D^{\ast\pm} and a muon in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114pb-1. Low transverse-momentum thresholds for the muon and D* meson allow for a measurement of beauty production closer to the production threshold than previous measurements. The beauty signal was extracted using the charge correlations and angular distributions of the muon with respect to the D* meson. Cross sections for photoproduction and deep inelastic scattering are somewhat higher than, but compatible with, next-to-leading-order QCD predictions, and compatible with other measurements.
    Full-text · Article · Mar 2007 · European Physical Journal C
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    ABSTRACT: In dynamic computation ecosystems involving many different participants, a topdown approach to system dependability does not work. It is not possible to take a topdown approach to system design and implementation and to validate the resulting system against some specification. Rather, we have to assume that elements of the system will become unavailable at unpredictable times and that some elements may be unreliable. Instead of designing systems to avoid failure, we must re-orient our thinking and design systems so that we can tolerate failure and recover from failures when they occur. In this talk, I will discuss the challenges of designing for failure and will introduce research on responsibility modelling that provides information for failure recovery.
    Preview · Conference Paper · Mar 2007
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    ABSTRACT: The production of energetic neutrons in ep collisions has been studied with the ZEUS detector at HERA. The neutron energy and distributions were measured with a forward neutron calorimeter and tracker in a sample of inclusive deep inelastic scattering (DIS) data and a sample of photoproduction data. The neutron yield in photoproduction is suppressed relative to DIS for the lower neutron energies and the neutrons have a steeper distribution, consistent with the expectation from absorption models. The distributions are compared to HERA measurements of leading protons. The neutron energy and transverse-momentum distributions in DIS are compared to Monte Carlo simulations and to the predictions of particle exchange models. Models of pion exchange incorporating absorption and additional secondary meson exchanges give a good description of the data.
    Full-text · Article · Mar 2007 · Nuclear Physics B
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    ABSTRACT: Inclusive-jet and dijet differential cross sections have been measured in neutral current deep inelastic ep scattering for exchanged boson virtualities Q(2) > 125 GeV(2) with the ZEUS detector at HERA using an integrated luminosity of 82 pb(-1). Jets were identified in the Breit frame using the k(T) cluster algorithm. Jet cross sections are presented as functions of several kinematic and jet variables. The results are also presented in different regions of Q2. Next-to-leading-order QCD calculations describe the measurements well. Regions of phase space where the theoretical uncertainties are small have been identified. Measurements in these regions have the potential to constrain the gluon density in the proton when used as inputs to global fits of the proton parton distribution functions. (c) 2006 Published by Elsevier B.V.
    Full-text · Article · Mar 2007 · Nuclear Physics B
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    ABSTRACT: French SummaryLa céramique de l'ArmadaCOLIN J. M. MARTINLa classification et l'analyse dc la céramiquc trouvée dans différentes épaves de l'Armada (Girona, S. Maria de la Rosa et Trinidad Valencera) mettent en évidcnce des centres de fabrication (a Séville, Mérida, Lishonne, Saint-Sébostien) de divers types de poterie ibérique dont la forme avait une relation avec le contenu. On relève aussi différentes méthodes utilisées pour fabriquer la cémique vernissée ou non. Trois tessons vernissés à l'aide d'étain et six non vernissés, de couleur rouge, ont été analysés sous l'aspect pétropaphique. On compare la classification de Goggin et les collections de Langouez de Grande-Bretagne. Les archives de Simanca sont utilisées pour dénommer la vaisselle découverte dans cette épave, et qui était officiellement en usage sur l'Armada.
    No preview · Article · Feb 2007 · International Journal of Nautical Archaeology

  • No preview · Article · Feb 2007 · International Journal of Nautical Archaeology

  • No preview · Chapter · Feb 2007

  • No preview · Article · Jan 2007 · Early Medieval Europe
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    ABSTRACT: Diffractive photoproduction of D*±(2010) mesons was measured with the ZEUS detector at the ep collider HERA, using an integrated luminosity of 78.6pb-1. The D* mesons were reconstructed in the kinematic range: transverse momentum pT(D*) > 1.9GeV and pseudorapidity |η(D*)|<1.6, using the decay D*+→D0π+ s followed by D0→K-π+(+c.c.). Diffractive events were identified by a large gap in pseudorapidity between the produced hadronic state and the outgoing proton. Cross sections are reported for photon–proton centre-of-mass energies in the range 130 < W < 300GeV and for photon virtualities Q2 < 1GeV2, in two ranges of the Pomeron fractional momentum xIP<0.035 and xIP<0.01. The relative contribution of diffractive events to the inclusive D*±(2010) photoproduction cross section is about 6%. The data are in agreement with perturbative QCD calculations based on various parameterisations of diffractive parton distribution functions. The results are consistent with diffractive QCD factorisation.
    Full-text · Article · Jan 2007 · European Physical Journal C
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    ABSTRACT: To examine the role of public health agencies (PHAs) in providing access to drug treatment services for adolescents by describing the proportion of youth who obtain access to these services through PHA involvement in school health clinics, juvenile drug courts, and other community agencies. Analysis of cross-sectional telephone interview data collected from 1999-2003 from a national sample of 1793 PHA key informants from communities surrounding schools in the nationally representative Monitoring the Future (MTF) study of 8th, 10th and 12th grade students. Fifty-eight percent of youth in the MTF sample were served by PHAs that participated in some way in school health clinics, with 30% served by PHAs that provided resources for drug treatment in schools. Twenty-nine percent of youth were served by PHAs involved in juvenile drug court (JDC) programs, 23% by PHAs acting as JDC referral agencies, and 13% by PHAs providing direct JDC drug assessment, treatment and monitoring services. In addition, 44% of youth were served by PHAs providing drug treatment resources in community settings. Treatment access for youth through PHAs varied by region, race/ethnicity, urbanicity, community income level, and youth population density. The largest variation occurred in access via JDC programs. PHAs may help bridge gaps between drug treatment need and service provision for adolescents who need access to drug treatment services. Strengthening the linkages between PHAs and schools, juvenile drug courts, and other community settings may serve to increase youth access to drug treatment.
    No preview · Article · Jan 2007 · Journal of Adolescent Health
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    ABSTRACT: In previous studies we developed a general compartmental methodology for modeling animal behavior and applied the methodology to marine birds and mammals. In this study we used the methodology to construct a system of two differential equations to model the dynamics of territory attendance and preening in a gull colony on Protection Island, Strait of Juan de Fuca, Washington. We found that colony occupancy was driven primarily by abiotic environmental conditions, including tide height, time of day, solar elevation, and wind speed over open water. For birds in the colony, preening behavior was driven to some extent by abiotic environmental conditions (including time of day, solar elevation, humidity, and wind speed on the colony), but apparently was driven primarily by local and/or biotic effects not included in the model. In terms of R(2) values, the model explained 65% and 37% of the variability in colony occupancy and preening data, respectively, as a function of these six abiotic environmental factors.
    Full-text · Article · Jan 2007 · Journal of Biological Dynamics
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    ABSTRACT: A new method is employed to measure the neutral current cross section up to Bjorken-x values of one with the ZEUS detector at HERA using an integrated luminosity of 65.1pb-1 for e+p collisions and 16.7pb-1 for e-p collisions at Ös=318GeV\sqrt{s}=318\,\mathrm{GeV} and 38.6pb-1 for e+p collisions at Ös=300GeV\sqrt{s}=300\,\mathrm{GeV}. Cross sections have been extracted for Q2≥648GeV2 and are compared to predictions using different parton density functions. For the highest x bins, the data have a tendency to lie above the expectations using recent parton density function parametrizations.
    Full-text · Article · Dec 2006 · European Physical Journal C
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    ABSTRACT: The photoproduction of prompt photons, together with an accompanying jet, has been studied in ep collisions at a centre-of-mass energy of 318GeV with the ZEUS detector at HERA using an integrated luminosity of 77pb-1. Cross sections were measured for the transverse energy of the photon and the jet larger than 5 and 6GeV, respectively. The differential γ+jet cross sections were reconstructed as functions of the transverse energy, pseudorapidity and xγ obs, the fraction of the incoming photon momentum taken by the photon-jet system. Predictions based on leading-logarithm parton-shower Monte Carlo models and next-to-leading-order (NLO) QCD generally underestimate the cross sections for the transverse energies of prompt photons below 7GeV, while the kT-factorisation QCD calculation agrees with the data better. When the minimum transverse energy of prompt photons is increased to 7GeV, both NLO QCD and the kT-factorisation calculations are in good agreement with the data.
    Full-text · Article · Dec 2006 · European Physical Journal C
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    ABSTRACT: This study examined the effects of two variables—descriptive cover letter and pre-letter to respondent's secretary—on response rate to a mailed survey. Two hundred randomly selected Michigan elementary school principals were sent the Eysenck Personality Inventory. There was no significant difference (χ2= .55, p > .05) in the rate of response between those administrators who received the descriptive cover letter and those who received no descriptive cover letter. However, those whose secretaries had been sent a pre-letter responded at a higher rate (χ2= 11.70, p < .001) than those whose secretaries received no pre-letter.
    No preview · Article · Dec 2006 · Personnel Psychology
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    ABSTRACT: Two species of animals are competing in the same environment. Under what conditions do they coexist peacefully? Or under what conditions does either one of the two species become extinct, that is, is either one of the two species excluded by the other? It is natural to say that they can coexist peacefully if their rates of reproduction and self-limitation are relatively larger than those of competition rates. In other words, they can survive if they interact strongly among themselves and weakly with others. We investigate this phenomena in mathematical point of view. In this paper we concentrate on coexistence solutions of the competition model $$\left\{ {\begin{array}{*{20}c} {\Delta u + u(a - g(u,v)) = 0,} \\ {\Delta v + v(d - h(u,v)) = 0in\Omega ,} \\ {u|_{\partial \Omega } = v|_{\partial \Omega } = 0.} \\ \end{array} } \right.$$. This system is the general model for the steady state of a competitive interacting system. The techniques used in this paper are elliptic theory, super-sub solutions, maximum principles, implicit function theorem and spectrum estimates. The arguments also rely on some detailed properties of the solution of logistic equations.
    Full-text · Article · Nov 2006 · Czechoslovak Mathematical Journal
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    ABSTRACT: The popular idea that mental calculation involves covert operations as counterparts to the scribblings, sayings or manipulations involved in classroom calculation is rejected by familiar arguments in Section I. Philosophers do not readily agree on an alternative account. Section II considers reasons why they are puzzled, reasons which encourage a return to the discredited position. The currently fashionable Causal or Functionalist view is criticised in Section III. Section IV reconsiders the stubborn fact that when someone calculates in their head they do something at the time which explains their arithmetical successes or failures. Some dispositional descriptions are rejected as inadequate. Though a restrained dispositionalism is finally supported, it does not have the implication that nothing was going on in the silence.
    No preview · Article · Oct 2006 · Ratio
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    ABSTRACT: Pulse coherent radar and pulsed magnetic resonance spectrometry are closely related techniques which share similar design constraints and technological difficulties, despite the obvious differences in application. Millimetre wave pulsed electron spin resonance (ESR) spectrometry is a rapidly developing scientific technique which is at the forefront of pulse coherent mm-wave instrumentation. Our work in developing technologies for sub-nanosecond pulsed ESR may be directly applied to radar, where extremely short pulse lengths offer very high range resolution and clutter suppression. Sub-ns ESR has been made possible by the careful design of the transmit/receive electronics and the use of quasi-optical (QO) techniques for signal transport and control. We present results for a low phase noise sub-ns pulse generator, high performance isolators, ultra low return loss QO loads, and a demonstration of ns coherent pulse demodulation
    No preview · Conference Paper · Oct 2006
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    ABSTRACT: Toward the end of the nineteenth century, merchants from Palestine settled in Transjordan. Many were taking advantage of new land-tenure policies implemented by the Ottoman state that were designed to create private landholdings, encourage market,based agricultural production, increase the state's tax base, and help in the state's modernization efforts. In the process, some of the new settlers consolidated their resources and capital, established large farmsteads, and became important merchants and local notables. At the same time, the construction of large farmsteads by these new "pioneers" changed the lives of the tribal groups and peasant fellahin already living in the area.
    Full-text · Article · Sep 2006 · Journal of Near Eastern Studies
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    ABSTRACT: A retrospective, descriptive study of clients with shoulder dysfunction referred to physical therapy. To (1) describe the clinical and functional outcomes of clients with shoulder dysfunction following outpatient physical therapy, and (2) to compare the outcomes by type of shoulder dysfunction. Although individuals with shoulder dysfunction are commonly referred to physical therapy few large descriptive studies regarding outcomes following physical therapy are available. Data for 878 clients (468 female, 410 male) were retrieved and analyzed. This database was developed between 1997 and 2000 and included 4 outpatient facilities from 1 healthcare system in the southwest corner of Michigan. Clients were classified by type of shoulder dysfunction, and standardized tests were performed upon admittance and discharge to physical therapy. Descriptive and inferential statistics were calculated for all data. Of all clients, 55.1% had shoulder impingement, while 18.3% had postoperative repair, 8.9% had a frozen shoulder, 7.6% had a rotator cuff tear, 3.0% had shoulder instability, 2.1% were post fracture, and the remaining 4.9% had miscellaneous diagnoses. The average (+/-SD) age of the patients was 53.6 +/- 16.4 years, with an average (+/-SD) number of treatment sessions of 13.7 +/- 11.0. All groups showed significant changes following physical therapy intervention. Clients with diverse types of shoulder dysfunction demonstrated improvement in both clinical and functional measures at the conclusion of physical therapy, although it is not possible to determine whether these changes were due to the interventions or due to time. The type of shoulder dysfunction appears to affect the prognosis, thus expected outcomes should be based upon initial diagnosis and specific measures.
    No preview · Article · Jul 2006 · Journal of Orthopaedic and Sports Physical Therapy
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    ABSTRACT: The preparation, spectroscopic characterisation and crystal structures of [FcP(mu-Se)Se]2, [FcP(mu-Se2)Se]2 and [PhP(mu-Se2)Se]2 are reported. Crystallographic data reveal planar four-membered PSePSe and skewed six-membered P2Se4 rings, respectively, in all cases with trans arrangement of organic substituents and exo selenium atoms. Whilst stable at room temperature in solid state, NMR data suggest the six-membered rings of both the ferrocenyl and phenyl compounds decompose in the solution with loss of red selenium, forming PSe2PSe five-membered rings.
    No preview · Article · Jul 2006 · Dalton Transactions
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    ABSTRACT: This research investigates the development of symbolic or representational play in two species of the genus Pan, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). The participants varied not only by species, but also as to whether they had become proficient in communicating with humans via a set of arbitrary visual symbols, called lexigrams. Using a developmental sequence of representational play based on McCune, we found every level that children manifest to be constructed by Pan. The most robust and regular ontogenetic sequence for both bonobos and chimpanzee was not McCune's five-level progression, but a three-step ontogenetic sequence: Level 1 (no representation, no pretense) precedes Levels 2–4 (representation but no pretense), which in turn precedes Level 5 (includes pretense as well as representation). A linguistic system for interspecies communication was necessary for Level 5 representational play and “true” pretense. Human scaffolding produced developmental progress within sequences for all the apes, except the bonobo who lacked a system of interspecies communication. This evidence suggests that the potential for representational play and its social stimulation were present in the common ancestor of bonobos, chimpanzees and humans five million years ago.
    Full-text · Article · Jul 2006 · Cognitive Development

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