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  • What have you learned from RG so far?
    RG is a great platform for exchange of ideas and thoughts between researchers. What added values did the RG experience give you?
    Hanno Krieger · Justus-Liebig-Universität Gießen
    @Joao, try it in this way: Goto your messages and then don´t type the message, instead you go to "View all". After that you see a list with all recent messages. The not already visited messages are shaded in light grey. It should work. Regards
  • Reference for amazing property of general matrix transformation between inertial frames?
    Given a general matrix to transform (x,t) to (x^\prime, t^\prime) between one inertial frame of reference and another, it is possible to show that, if you impose indistingishability between inertial frames, that the transformation tells you that there is an invariant speed. In fact you get the Lorentz transformations except the speed is some speed S... I cannot for the life of me remember where I came across this amazing (amazing to me at least) fact. I spent half the day showing this to be true, but I have no idea what journal paper or book to find it in and give some kind of decent reference? Help please?
    Chris Godsalve · Home
    Thanks Mozafar, that's exectly what I needed! I have managed to read a couple, and it's definitely the stuff I re-derived yesterday. So: I have references for my article. Thanks again, Chris
  • Is it feasible to make an object fully invisible?
    Being transparent or creating an illusion? I may propose a device to transfer the images from one location to display at another location using the optical fibers. Furthermore, invisibility may be re-defined over different IR-visible and UV spectral ranges. What optical materials, nanostructures or hybrid mechanisms can be used to enhance the invisibility process?
    Gayan Illeperuma · The Open University of Sri Lanka
    Hi everyone, Sorry for the late reply (We celebrated our new year in Sri Lanka and was super busy). I think there are two ways to look at the problem. I agree with Anton to a certain extent. We have to understand what 'invisibility' means in this context. Is it been un noticeable to human perception ? Or is it that you cant see/ detect it with anything. For example with a high speed camera 50Hz rotation would become visible
  • Paul Hubert Vossen added an answer in Group work
    Does anyone recommend a good method in assessing group work?
    To assess group work, one of the challenges is to ensure the fairness. What are the approach you have test which balances the weight between group and individual performance? Could you please share? Any other important issues when talking about group work assessment? I am really eager to learn from your experience.
    Paul Vossen · Duale Hochschule Baden-Württemberg Mannheim
    [continued from previous contribution] Several further improvements on this simplistic idea are possible. For instance, self-assessments of all students may be used to calculate a correction factor ("tolerance parameter") to be applied to the peer-assessments, counteracting any notable tolerance of team members. Or a group factor G > 0 will be calculated on the basis of the actual individual performance such that this individual performance is just multiplied with G: extra advantage is, that poor group performers get penalized in that there original individual score will be decreased! In the schemes of reference below this is not possible at all: group work will *always* be rewarded, even if counter-productive. With all these improvements, one basic flaw of simplistic self- and peer assessment is still not resolved: it is purely holistic assessment, jugling around with abstract ratings. In a preferred analytic approach, one should specify several criteria on which assessment will be done, not just a holistic-generic "contribution to the group", which can mean different things to differnt students judging different mates in the group.
  • Sudharsan Ds added an answer in Embedded Linux
    ARM cross compilation in linux
    Am having set of user level and kernel level files.am using arm-linux-gnueabi cross compiler for compilation. All the user level file got compiled.thing is when cross compiler enters kernel level throwing linux/version.h,linux/init.h missing. is it linking problem or anyother way to proceed
    Sudharsan Ds · SRM University
    thank you Daniel Franklin ,yes am working with ubuntu. let me try it with above mentioned library .
  • Ashwani Kumar added an answer in Enzymology
    Active site of enzyme
    Why the active site of very active enzyme is buried at all
    Ashwani Kumar · Jaypee University of Information Technology
    according to me if the active site is buried the substrate will be surrounded almost 360 degree by the protein permitting multiple S-E interactions which in turn will create a more effective transition state
  • Pawel Buczkowicz added an answer in Complexity
    How to get information about location of all genes on their respective chromosomes in terms of their base pair range address ??
    Example if a gene X is located on chromosome 2 in the region between 10000bp and 16000bp. I want to get this kind of information about the location of genes for all human genes . I guess the data is available online and it's just a matter of knowing how to access the data !
    Pawel Buczkowicz · SickKids
    If you want to look up the locations of a few specific genes you can find it using the UCSC genome browser: http://genome.ucsc.edu/cgi-bin/hgGateway If you want to get lists of all genes and their location (as tab delimited text files for example) you can always try: http://www.ncbi.nlm.nih.gov/refseq/ http://www.genenames.org/
  • Jagatbikas Nanda added an answer in Sediments
    Is it possible to differentiate Ortho- and Para-amphibolites based on geochemistry?
    We have amphibolites which clearly show sedimentary structures like bedding planes and are associated conformably with other sediments like greywackes, banded iron formations, dolomitic limestones and impure quartzites. Also, they consist of detrital quartz grains. The amphibolites mainly consist of tabular and prismatic hornblende and sub-rounded to well-rounded quartz set in a meager fine grained matrix of quartz, chlorite and sericite. But they have negligible felspars and when plotted in chemical classification diagram they fall into ortho-(igneous) amphibolite category. So is there any way for classifying the aphibolites into Ortho (igneous) and Para (sedimentary) amphibolites.
    Jagatbikas Nanda · IIT Kharagpur
    Please read ,,,,,Discriminant function equation......there is spelling error
  • Does poetry matter in your life?
    Do you have any pieces of text, poets or poems that you like for some reasons? I think, line verses spoken or read for pleasure, move us to another level of human functioning, giving respite and relaxation. Poetry can also enrich and enable us, academics to go beyond the closed professional jargon and specialized language. In my opinion, original, dramatic and enchanting is poetry of Charles Bukowski. I share link to his poem entitled "So you want to be a writer?". http://www.youtube.com/watch?v=oaiieWJnxms Do you have favorite poets or poems ? Does poetry read or listened matter in your life?
    K. C. Patrick Low · University of the South Pacific
    I like rhythms . Ha2, aha2 even chanting and they really amazing me. Cheers
  • Jose Gros added an answer in Cancer Biomarkers
    Can all malignant tumors (cancers) metastasize to other organs?
    Cancers metastasize via seeding through blood or lymphatic vessels.
    Jose Gros · Sociedad Española de Oncología Médica
    I'd say yes, he died because his BSC or from direct complications of surgery, I don't remember well, but it may have been a bacteriane CNS infection. Thanks for the interest. Those who studied his life reported that while he was in his home's living room discussing his invention with some alien possible purchasers, the shoes of two persons hidden behind a curtain were visible. Salut †
  • B.R. Vishvakarma added an answer in Antenna Design
    Can anyone help with a microstrip patch antenna?
    I have designed a microstrip patch antenna that works in 2.4 Ghz , but its bandwidth is 30 Mhz, I want to improve the BW, how can I do it?
    B.R. Vishvakarma · Banaras Hindu University
    You can improve the BW of the patch on any substrate using several techniques like cutting slots on the patch, stacking one or two ptches,parasitic patches.
  • Faeze Khatibi asked a question in Biomathematics
    How can we check the stability or instability of delay differential equation ?
    I want to know the method that determine stability of dde for all situation.
  • I think software cost estimation is a problem before requirements, what's your thinking?
    Define the price of the software is big issue in software development. For example, say someone asked how much money it took to make a xxxx software (or any software). They did not say anything about this software but asked only how much it cost (without requirement). But what could be the answer, because without the necessary information it can't be answered. In the case of software development many have a cost estimation but have no way to do a software development cost estimation without requirement collection. Is this also a problem you have come across? So, this a problem? What do your think?
    Martin Shepperd · Brunel University
    Also remember a prediction is a *probabilistic statement* and not just a point value. This means that if you have very little information about the software that's required then you will have upper and lower bounds that are widely separated coupled with relatively low confidence. For example I might have 50% confidence that the actual cost will fall between 1m and 5m euros/dollars/pounds (or whatever your favourite currency is).
  • Boon Chin Tan added an answer in Abiotic Stress
    During abiotic stress conditions for crop plants , the level of soluble proteins increase or decrease ? And why ?
    If abiotic stress is given for 1 week to any crop plants then wat alterations occur in level of soluble proteins ?
    Boon Chin Tan · University of Malaya
    It's depends. The plant protein content might increase when under stress, probably due to the production of stress-related proteins in response to the environment. Please also note that the reduction of protein content might due to the losses of some proteins during extraction.
  • Didn’t computer science violate the basic scientific process?
    Please let me summarize my understanding of the process (or steps) for scientific and technological progress. Step-1: The purpose of scientific research is to discover new facts for expanding the boundaries of human knowledge. Step-2: The purpose of engineering research is to choose and rely on a “set of necessary facts” to invent useful new things or innovate improvements for existing useful things. The technology progress is nothing but making such useful inventions and innovations by relying on the facts discovered in scientific research. It is a well established fact that every technological invention or innovation must rely on certain essential scientific facts. No useful thing can be invented or innovated successfully by relying on facts having errors (e.g. erroneous axioms by assuming to be facts). That is, no invention or innovation could work as expected if there are errors in the “set of necessary facts” (on which the researcher relied for the invention or innovation). All the inventions and innovations mankind is enjoying today in the 21st century are empirical evidence and/or testament to the extremely high degree of accuracy of countless facts. I can prove that software researchers violated basic scientific process by skipping the step-1 and defined nature and essential properties of many kinds of components for software products (without any basis in reality or facts). Then again, software engineering paradigm defined many kinds of CBSDs (Component Based Design for Software Products), where each kind of CBSD is nothing but using a kind of so-called component for software. My understanding of the scientific process is that mankind can’t define or dictate the nature or essential characteristics of any kind of physical beings (e.g. animals, trees or ideal physical functional components) and mankind can’t define or dictate the nature or essential aspects of any physical phenomenon (e.g. achieving controlled powered flight or achieving ideal CBD for physical products). The existing Geocentric-paradigm of software engineering evolved by relying on this huge bug (by erroneously assuming the bug is a fact) for over 45 years: Any kind of software parts either having certain useful properties (e.g. reusable or standardized) or conforming to a so-called component model is a kind of component for software (i.e. software-components). Using each kind of these so-called software components is a kind of CBSD (Component-Based Software Design). This resulted in many kinds of so-called software components and so-called CBSDs. In the context of physical products, there is no ambiguity in the questions “what are components?” and “what are not components?” (e.g. ingredient parts such as lead and acid in lead-acid batteries; steel, cement, metal-alloys, plastic or silicon in semiconductor chips). It is a huge error to assume any other kind of useful parts are components for software, since no other kind of physical parts except a very special kind of parts having certain essential characteristics can be physical components. It is possible to discover essential characteristics uniquely and universally shared by each and every known physical functional component. Once the essential characteristics are discovered it is possible to invent real software-components, which are equivalent to the physical functional components by having the essential characteristics. I believe it is absolutely essential to discover essential characteristics uniquely and universally shared by ideal physical functional components. For example: Basic sciences can’t be real science if the best researchers in the field don’t know the nature and essential characteristics of basic building blocks. If no zoologist in the world can name essential characteristics of animals, then zoology can’t be a real science. If no botanist in the world can name essential characteristics of trees, then botany can’t be a real science. The same logic applies to software engineering and computer science. Until software researchers discover essential characteristics and innate nature of basic building blocks such as real-components and CBD, software engineering and computer science can’t be real-engineering and real science respectively: http://real-software-components.com/forum_blogs/year2014/Messy-State-of-CBSD.html The objective of my research is to invent real-software-components, enabling tools and mechanisms for achieving real CBD for software (i.e. high degree of modularity): http://real-software-components.com/forum_blogs/year2014/Vision-Goals.html. If scientists are willing to analyze all the available facts, valid observations and known concepts of CBD (Component Based Design) of any complex one-of-a-kind product such as an experimental jet-fighter or spacecraft, it is not hard to prove that the essential purpose of components is achieving the highest degree of modularity: http://real-software-components.com/technologies/CBD-facts-rules.html & http://www.researchgate.net/publication/260795179_New_kind_of_Software_components_for_achieving_superior_modularity?ev=prf_pub
    Jonathan Kimmitt · Anglia Ruskin University
    Your question at the head of the topic is eye-catching, but what you are actually talking about seems largely unrelated. There may well be shortcomings in computers that we use nowadays due to false assumptions but this is because they only model discrete mathematics, they do not prove it. The underlying proofs are as robust as any scientific theory or mathematical theorem. I think you will find Copernicus and not Galileo was the first person to discover the heliocentric cosmos (the word at the time meant only our solar system). Galileo only got into trouble for proving it. But I fail to see what this has to do with GUIs or 300 page patents. (Software patents in any case are not accepted in Europe).
  • Tolga Yarman added an answer in Gravity
    An old question that is still fresh: Is gravity a Newtonian force or Einstein space-time curvature?
    No gravitational wave was measured yet, no graviton was detected accordingly. On the other hand no space- time curvature was observable. There is no successful experiment to validate the current theories. What is the nature of the mysterious gravity? What is the velocity of this effect ?
    Tolga Yarman · Okan Universitesi
    How is that :)) ... http://news.nationalgeographic.com/news/2014/01/140127-black-hole-stephen-hawking-firewall-space-astronomy/ ...
  • Jim Arnold added an answer in General Relativity
    Why is there so much fuss over the twin paradox in General Relativity?
    In the twin paradox, AA is the brother who stays on Earth and BB the traveler who is moving away from the earth, in the rocket. When BB returns, AA thinks that BB is the youngest because the speed of the rocket was almost c. However, BB believes that the Earth is who took away his brother from him and when they are reunited, notes that AA has not aged as much as he. Clearly, if there is no preferred reference frame, they cannot feel a difference in age.
    Jim Arnold · Penngrove U
    "where in SR is acceleration discussed?" Eric: "In any introduction to SR that goes a little further than Lorentz equations, inertial frames, length contraction and time dilation." But that's going further than SR! Charles: "The laws of physics describe the accelerations of objects in inertial frames." An "inertial frame" is precisely non-accelerating. Special Relativity deals with uniform (unaccelerated) motion. Einstein had no idea how to incorporate acceleration or gravitation when he published his paper in 1905, and he specifically avoided those questions.
  • Is it rational to use student's t-test for larger sample?
    Normally t-test is supposed to be used for comparing data of small samples, e.g. <30. We see many publications using the t-test for sample sizes larger than 30 to compare two groups data. Why is this the case?
    Rafael Roman · University of Zulia
    I did not want to answer this question , Because, it seens to me that Eik 's answer is good enough. In General , "t" tests are used in small sample sizes ( < 30 ) and " z " test for large sample sizes ( > 30) . The 30 is a rule of thumb, for the overall case, this number was set by good statisticians. But Perhaps, for some distributions the number could be less than 30 , say for example 25 , and for other distributions the number could be 45, also as an example. It depends on the variability of the distribution. You get to this point, if you with your estimate of the sample variance and the magnitude of the difference between the two populations, you estimates the sample size for detecting true differences between the two populations at certain levels of type I and type II error. The Central limit theorem asures us that mount shaped distributions converges to the Normal distribution for large sample sizes. In General Most books, when autor covers the "t" distribution generally overlay the " t" and "z" distribution, In that graph you can see where are the differences between the two distributions ( mainly in the tails ) . What we should Worry about is on the assumptions made under any statistical test. Finally I would say that is the underlying assuptions for a statistical test are met, I would not see differences with both tests. Using the other statistical test, that have been mentioned, depends on other assuptions which must be met.
  • Imtiyaz Khan asked a question in Signal Processing
    Can anybody tell me how Genetic Algorithm (GA) can be used for optimum selection between available resources?
    If we have a set of available data and i want to select particular optimum data for particular condition. Can we take help of matlab toolbox for that purpose....Is there any references where i can get how i can simulate that function using matlab....
  • Tobias Dehling added an answer in IT Management
    How do we measure effectiveness of Information Systems in an organization ?
    Is there any methodologies and reference to measure effectiveness of Information Systems application and information in an higher learning organization ?. Can we implement COBIT or ITIL in an educational institution ?
    Tobias Dehling · University of Cologne
    I guess this depends on your definition of effectiveness. If you want to measure whether users accept the information system, you could use the Technology Acceptance Model (Davis, 1989). If you want to measure whether the information system is used, you can use the Unifed Theory of Technology Acceptance and Use (UTAUT; Venkatesh et al. 2003). If you want to measure whether the system achieves some desired outcomes, you could use the Information System Success Model (DeLone & McLean, 1992, 2003). The Association for Information Systems lists a whole bunch of theories to measure IS 'effectiveness' in some form (http://istheory.byu.edu/wiki/Main_Page).
  • Which is better for image processing (3D images) and visualisation - C/C++ or PYTHON/PYTHON with numpy or MATLAB?
    For 3D image processing, using linear Algebra, working with tensors, which language offers more tools to do that, simply, easily and faster?
    José Iglesias Gamarra · University of Magdalena
    I worked with c++ and openCV in Computer Vision and i'am satisfied
  • Should the letter ‘e’ in e-learning mean ‘no face to face interaction’?
    There has been a tremendous advancement in computation and communication technology. The concept of e-learning has come into existence. The proponents of this form of education suggest complete automation that is totally to avoid human interaction in the classroom. What is in your opinion, what should be the correct pedagogy which would be compatible to present technological advancement?
    Barbara Hall · Ashford University
    I would challenge the assertion that e-learning means "to avoid human interaction in the classroom," as suggested in the initial question. I would argue that e-learning involves a broad view of a learning environment - or multiple environments - in which there is a form of interaction mediated by digital technologies. This could include a blended or wholly online courses. The second part of the question does not necessarily seem related to the first. The "correct pedagogy...to present technological advancement" would involve a multitude of factors, many of which would be situation specific. We would need to conduct analyses of the tasks, learning environment(s), performance environment(s), and learners.
  • Is there any test method (quantitative or qualitative) for trixylyl phophate?
    Please follow the following link:http://echa.europa.eu/candidate-list-table m.wt:416.49
    William Berkowitz · CUNY Graduate Center
    Hi, One of these may be able to help. Bill 1. Aircraft-grade high-pressure fire-resistant oil using trixylyl phosphate as basic oil and production method thereof By Zhang, Yungang; Zhang, Chuanyi; Zhao, Chunzhong; Liu, Xuekun From Faming Zhuanli Shenqing (2013), CN 103215106 A 20130724, Language: Chinese The present invention relates to an aircraft-grade high-pressure fire-resistant oil using trixylyl phosphate as base oil and prodn. method thereof. The oil is composed of trixylyl phosphate and bis(tert-butylphenyl)phenyl phosphate at wt. ratio 3.5-4.5:1.5-3, also contains epoxy soybean oil octyl ester 0.3-0.5, antioxidant 0197 0.5-0.6, triazole 0.8-1.1, and di-Me silicone oil 0.4-0.5 wt.%. The prodn. method comprises mixing trixylyl phosphate and bis(tert-butylphenyl)phenyl phosphate at a mass ratio of 3.5-4.5:1.5-3 for 1.5-2.5 h, adding the mentioned additives into the mixed oil and stirring to give a mother liq., stirring the mother liq. at 65±2°C and balancing for 3-5 h, filtering at 65±2°C through a 50-70 mesh sieve and balancing for 14-17 h, and analyzing fully. The product has low Cl content, low acid value, high ignition point, high b.p., good lubricity, abrasion resistance, aging resistance, foam resistance, flame resistance and thermal stability. ~0 Citings 2. GC-MS determination of phenol phosphates in nipple By Lu, Chun-mei; Han, Da-chuan; Lu, Li-jun; Mu, Jun; Zhao, Qing-song; Fu, Xin From Lihua Jianyan, Huaxue Fence (2011), 47(10), 1165-1167. Language: Chinese A method for detn. of 3 phenol phosphates i.e., tricresyl phosphate (TCP), cresyl di-Ph phosphate (CDP) and trixylenyl phosphate (TXP), in nipple by GC-MS was proposed. The 3 phenol phosphates in sample was extd. with Et acetate, and the exts. were concd. by rotary evaporator in a water bath at 35°. The residue obtained was dissolved and made up to 2.0 mL with methanol, which was used for GC-MS anal. The DB-1701 capillary chromatog. column (30 m × 0.25 mm, 0.15 μm) was used for sepn., and the electron impact ionization source with selected ion monitoring (SIM) was adopted in MS. Linear relationships were obtained between values of peak area and mass concn. of the 3 phenol phosphates in the same range of 30.0-500 μg/L-1, with lower limit of detn. (10 S/N) of 30 μg/kg-1. Tests for recovery and precision were made by std. addn. method at 3 different concn. levels, values of recovery and RSD's (n = 10) found were in the ranges from 64.0% to 88.5% and 0.86% to 8.7% resp. ~0 Citings 4. Determination of solubility parameters and thermodynamic properties in hydrocarbon-solvent systems by gas chromatography By Diaz, E.; Cazurro, A.; Ordonez, S.; Vega, A.; Coca, J. From Brazilian Journal of Chemical Engineering (2007), 24(2), 293-306 DOI:10.1590/S0104-66322007000200014 Gas chromatog. used to calc. the specific retention vol. of several hydrocarbons in different chromatog. liq. phases (Squalane, Carbowax-400, Carbowax-1500, Carbowax-4000, Amine-220, Dinonyl phthalate, Tri-Bu phosphate and Trixylenyl phosphate). Some thermodn. parameters, such as enthalpy of sorption and Flory-Huggins parameters relating the interaction between liq. phases and solutes, were also calcd. from the detd. retention vols. Liq. phase soly. parameters of Squalane, Carbowax-400, Carbowax-1500 and Carbowax-4000 at 80° as well as the polar and apolar components were calcd. too. A new model was proposed to correlate polar contribution to the soly. parameter of a liq. phase with the specific retention vol. of a solute in this liq. phase. ~3 Citings 7. Ion composition elucidation (ICE): A high resolution mass spectrometric tool for identifying organic compounds in complex extracts of environmental samples By Grange, Andrew H.; Osemwengie, Lantis I.; Genicola, Floyd A.; Sovocool, G. Wayne From Preprints of Extended Abstracts presented at the ACS National Meeting, American Chemical Society, Division of Environmental Chemistry (2001), 41(2), 669-676. For target analytes, stds. are purchased, extn. and clean-up procedures are optimized, and mass spectra and retention times for chromatog. sepn. are obtained to compare target compds. in environmental sample exts. This is an efficient approach and selective extn. and clean-up can decrease detection limits for target compds. relative to analyzing a raw ext. contg. compds. which yield mass interferences. However, selecting a class of compds. for study ignores many potentially toxic compds. which should be considered. Ion compn. elucidation (ICE) is a tool using high resoln. mass spectrometry which makes practical characterization and identification of many compds. responsible for chromatog. peaks obsd. for complex environmental samples. ICE has 2 facets: mass peak profiling from selected ion recording data to acquire data; and a profile generation model to plan expts. and interpret data. Up to 31 m/z ratios are monitored sequentially each second across up to 4 analyte and 2 calibrant mass peak profiles. Area under each analyte chromatog. peak in ion chromatographs are plotted to provide the analyte full or partial mass peak profiles. Up to 3 such data acquisitions are made for each analyte ion using a successive approxn. approach. Organoarsenic compds. in polluted groundwater, pharmaceuticals in wastewater, and organophosphate compds. in environmental matrixes were identified using this method. ~0 Citings 13. Analytical methods for environmental studies of chemical substances. 22. Identification [and determination] of organic phosphates in sediments by gas chromatography-mass spectrometry. II By Kenmotsu, Katashi; Nakagiri, Motoharu; Ogino, Yasuo; Matsunaga, Kazuyoshi; Ishida, Tatsuo From Okayama-ken Kankyo Hoken Senta Nenpo (1983), 7, 143-9. Language: Japanese Gas chromatog. and gas chromatog.-mass spectrometry (GC/MS) were successfully used in conjunction with a GC/MS data search file to identify and det. trixylenyl phosphate, dixylenyl (trimethyl)phenyl phosphate, Ph di(isopropylphenyl) phosphate, tricresyl phosphate, trioctyl phosphate, etc. in water and river sediment heavily contaminated by household sewage. ~0 Citings 15. Studies of the detection and determination of trixylyl phosphate in biological material By Karkalis, E.; Walther, G.; Penzes, L. From Beitraege zur Gerichtlichen Medizin (1983), 41, 117-22. Language: German, Trixylyl phosphate [ 25155-23-1 ] was detected in liver and kidney homogenates in EtOH by chromatog. on silica gel 60F254 plates with C6H6-EtOAc (9525-80:20) with diazotized paranitraniline spray reagent. For quant. detn., the spots were eluted with EtOH and the absorbance was detd. at 212 and 265 nm. The method is simple and rapid enough for use in poisoning cases. ~0 Citings 16. Environmental survey of chemicals. 19. Simultaneous determination of organophosphoric acid triesters By Kenmotsu, Katashi; Matsunaga, Kazuyoshi; Saito, Naomi; Ogino, Yasuo; Ishida, Tatsuo From Okayama-ken Kankyo Hoken Senta Nenpo (1982), 6, 126-32. Language: Japanese, Org. phosphate in river water, seawater, and sea sediment were detd. simultaneously by solvent extn. and gas chromatog. The hydrophobic phosphates and hydrophilic phosphates were collected in n-hexane layer and chloroform layer, resp. The interference of S-compds. was eliminated by floridil gas chromatog. For example, Me3PO4 [512-56-1] and Et3PO4 [78-40-0] recovery was 70-90% and 87-95%, resp. ~0 Citings
  • What are the discomforts related to weather and climate or climate change, that you are facing now?
    In my country, our daily temperatures have increased about 6 degrees Celsius, from 27 to 33. At times, it can be hotter. A few months ago, there was so much rain that some places were flooded. But recently our rainfall has decreased about 50 - 60 percent. Like little elephants or water buffaloes, we really feel so HOT, and need a dip in cold water, or at least a good shower! With this water rationing, elephants are having a cooler time, but I feel very uncomfortable. Are you facing similar discomforts?
    K. C. Patrick Low · University of the South Pacific
    The rainfall/ hot season patterns have been changed and become indistinct. Not so predictable - unlike previous years.
  • In what way the philosophers of the world contributed to education and research?
    Philosophy has always been considered as a corner stone for generating sound educational practices. Each region of the world has a great many philosophers who have enriched our lives through their teachings. A few examples that comes to my mind from the recent past in India is Sri Aurobindo and Jiddu Krishnamurti. There are many such eminent personalities that contributed to the thinking process. I would request you to enlighten us with the teachings of the philosophers from other regions so that we can get a broad view of all contributions. Thanks to all of you for your answers. http://schoolofeducators.com/2012/04/aurobindos-vision-on-education/ http://www.jkrishnamurti.org/krishnamurti-teachings/view-text.php?tid=43&chid=297
  • What is more appropriate: a population average or cluster (subject) specific?
    I am interested to know your typical practice. Do you typically report population average or cluster (subject) specfiic estimates; or indeed both? What informs your choice of what to do?
    Fernando Mata · Newcastle University
    I think it will depend on the existence of significant differences between the levels of factors discriminating to create the clusters,... if no significant differences between these then an overall mean probably would make more sense,... but all is relative you may be interested in reporting cluster means and stating nonexistence of significant differences,... and even nonexistence of significant differences is also relative once a p-value of 0.05 is just a subjective criteria,...
  • Tian Shi asked a question in TDDFT
    Expansion coefficients for certain excited state?
    In TDDFT Casida's ansatz, the wavefunction for a certain excited state can be expanded as a linear combination of KS orbitals, where the coefficients are the projection of LR orbitals on a subset of unoccupied KS orbitals. I'm wondering how can I get the information of these coefficients from Gaussian 09? Another question is I don't know if I understand KS orbitals right or wrong. Like in HF, each KS orbital is the linear combination of basis functions, where the coefficients are MO coefficients. The wave function of ground state is a slater derminant formed by KS orbitals. Is my statement right?
  • What mental exercises you suggest to promote a healthier thinking
    The mental brain health plays an essential role in almost everything we do. How to promote our mental brain health?
    K. C. Patrick Low · University of the South Pacific
    In my view, one needs to see or look at a variety of things, all kinds of scenery, greenery, landscapes, the hills, the mountains, the seas, the lakes, natural beauties, man-made beauties, paintings, sculptures, and the many different types of visuals - whatever that there are. Let the eyes feast. Let the eyes take delight. And let them enjoy the celebrations and beauty of all creations.
  • Satpal Kaur added an answer in SEM Operation
    In my SEM results I am getting a non-significant relationship and Std Reg Wght > 1. How can this be resolved or explained?
    I have 13 latent variables, 3 are second order. I am looking at the interaction among these.
    While doing CFA for each variable I managed to get very good model fit with reasonable loadings. The overall measurement model also showed good result. The SEM has acceptable fit with RMSEA < 0.05 so I don't know where else could the problem be. I realise I'm shooting in the dark but I don't know what else I can do.