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- 7Depth limitations of Cyphoma Gibbosum in the Caribbean?
Does anyone know the depth limitations of Cyphoma Gibbosum, Flamingo Tongue Sea Snail, in the Caribbean? I've done some digging and thus far have only found papers looking at their predation on soft corals at <7m depth. What is their maximum depth range? Any pointers in the direction of papers/knowledgeable individuals would be appreciated!
Ernesto's comments fit our observations in the Florida Keys, where we have rarely seen them below 10 m. They seem to be most abundant in the very shallow 1-3 m zone in areas where the gorgonians are abundant.Following
- 2What is the protocol to make urine acellular?
I need to make urine acellular to be able to store it and subsequently test it for ascorbic acid content.
Thank you very much for your help. Really appreciate it.
- 2Can you please help transfer a TeX format file to a DOC format file?
Happy Chinese Lunnar New Year!
I need to transfer a TeX format file (KJS-932.tex) to a DOC format file (word format file), can you help me? Please.
Feng Qi (F. Qi)
You can use converter program that named grindeq.Following
- 6What are the main Obstacles for Non-contact Heart rate monitoring methods/systems?
I want to monitor Heart rate and other physiological parameters of a Driver in real life situations in different environment (Day/Night) using non-contact systems ( like camera). What are the main things to be considered ?
Your valuable thinking/ suggestions are appreciable.Following
- 2What are the major trends in Information Retrieval (from earlier IRS to contemporary ones) ???
Need a list of some major breakthroughs in the field of IR since it has evolved!
Thanks.. but I am not having full access to this book.Following
- 2How to assay GSH and GSSG?
Kindly help with the protocol of end point assay for GSH and GSSG. Thanks in advance.
The spectrophotometric method for GSH involves oxidation of GSH 5,5'-dithio-bis(2-nitrobenzoic acid to form the yellow derivative 5'-thio-2-nitrobenzoic acid (TNB), measurable at 412 nm. The glutathione disulfide (GSSG) formed can be reverse to GSH by glutathione reductase in the presence of NADPH.
Rahman I1, Kode A, Biswas SK.Nat Protoc. 2006;1(6):3159-65Following
- 23Has it been scientifically proven that Zika virus is the cause of microcephaly?
Has it been scientifically proven through laboratory experiments that Zika virus is the cause of microcephaly?
New paper today in NEJM. http://www.nejm.org/doi/pdf/10.1056/NEJMoa1600651
Zika Virus Associated with MicrocephalyFollowing
- 2What are the impacts of boat traffic on macroinvertebrate assemblages in freshwater lentic systems?
As the question states I am looking for papers detailing the impacts of recreational boat traffic on benthic macroinvertebrate assemblages. Much of the research material I have found thus far is focused on marine and brackish waters. Are there any papers available specialising within lentic freshwater environments?
Other impacts include erosion and disturbance of shoreline habitats from boat wakes. In small freshwater lakes with a lot of boat traffic boat wakes can have a big impact on shoreline habitats. Also, boat traffic can disturb wildlife, the noise and wake can disturb nesting birds and foraging animals.
A big problem with boating traffic is the introduction of aquatic invasive species from watershed to watershed. Careless boaters can move non-native species from one water body to another through bilge water or through plants and other organisms clinging to the boat trailer or prop. Another source of introductions is the careless emptying of bait buckets which releases new potentially invasive species.
There is a fair amount of literature on these topics from research conducted in the Great Lakes and nearby watersheds.Following
- NewWhat is the future of bio medical engineering?
biomedical engineering is important for millions to help heart patients and all tools to help artificial organs ,which are now required by millionsThe human heart is a pump that is made of muscle tissue. A special group of cells
called the sinus node is located in the right atrium. The sinus node generates
electrical stimuli that make the heart contract and pump out blood. The normal
human heart beats about 75 times per minute (i.e., about 40 million times a year) –
i.e., the heart pumps 5 l of blood per minute. The normal systemic blood pressure is
120/80 mmHg. The mechanical power (calculated by multiplying the pressure by
the flow rate) of the human heart is about 1.3W. However, to provide this
mechanical power, the heart requires 10 times much higher rate of energy turnover,
owing to its low mechanical efficiency (less than 10%).
However, the development in biotechnology can open the opportunity for
tissue engineering (a branch of biotechnology) – a prospect of saving people with
extremely complex or irreversible failure heart will still be realized using mechanical
heart support devices.
During the last half-century, various blood pumps were introduced into
clinical practice, which can partially support or replace the heart during openheart
surgery or considerably for a longer time period until heart recovers or
until transplantation is performed. Several millions of people owe their health
and lives to these devices. According to the American Heart Association, an
- 3How long after library preparation can you safely sequence?
I performed a TruSeq library prep 2 months ago. Can I can re-sequence those same libraries now? Or is it recommended to redo the library prep? Illumina advises to sequence within 7 days, but has anyone had efficient sequencing outside of that window?
That's great. Thanks very much for the info. I'll run it on the BioAnalyzer just to be safe, but it hasn't left the -20C for two months so hopefully the quality hasn't changed.Following
- 4How can I find permittivity of p-doped silicon?Looking for optical parameters (like permittivity or refractive index) of p-doped Si.
I checked refractiveindex.info and Palik's book but found nothing.
Thanks Christian. it is so useful.Following
- 6Do you know any record about tsunamis in South Atlantic?
I would like information about tsunamis in South Atlantic.
- 5How can we compare two control approaches ?
I used to different methods to #control pressure in pump unit in #Power-take off system in #WEC. Obviously, the overall performance of the system is different.
I appreciate if you send me an article comparing two different control approaches applied for a same model.
Thanks Dear Koorosh
surely, these articles will be beneficial.Following
- 9How to justify level of accuracy for old Classified Landsat (TM) image?
I am doing land use change detection analysis for the years 1993,1999 and 2010 using Landsat (TM). I have some concerns regarding accuracy assessment of classified images. for the 2010 image i used google earth archive (2010) image as reference data but there is not archive images available for 1993 and 1999. Does it possible i can use closed year (2000) as reference? but i think it would not help for 1993 image. can you please suggest me if there is any other way to justify these two old images (1993 and 1999)?thank you so much
I agree with James, for the 1993 land cover map, you could also use the topographic maps of the area if they are available.Following
- 7Cellosolve and 2-methoxyethanol are equivalent?
I was wondering if someone can help me with this issue. I was told that chemical product called Cellosolve was a good way to clear insect pieces such as mouthparts, legs and abdominal tergites, and as such a good substitute to KOH. Some of my colleagues in US and South Africa use it and are quite satisfied. I thus bought this product under the name 2-methoxyethanol (C3H8O2), which has the same chemical formula. But my product does not work and no clearing is visible. Can someone help me? What is wrong? Many thanks in advance!
This product is a substitute for the permanent Xylene preparations, without the need to successive baths of absolute alcohol before going to euparal (artificial ointment). Not suitable for whitening, but for dissections and rapid preparation of small morphological parts (eg insect gills)Following
- 1Does laser power varies during cutting? Is there any way to measure the same?
Whenever cutting hard materials by contact methods the cutting force varies.
On the similar lines, does the laser power varies during metal cutting by laser?
The power of a laser is controlled to some extent by the power supply. Unless there is some feedback mechanism to change the output of the laser during cutting, the output of the laser remains constant (in mechanical cutting, the resistance of the material to cutting is mechanically communicated to the power source, generally a motor, which draws more current in response to thicker/tougher sections of material). In the case of a laser, it supplies a surplus of power to cut/ablate the material; if the remaining laser power could be measured, (for example, by a detector beyond the material being cut) then the power used in cutting could be measured by difference.Following
- 10As a non financial background ,what is the best way to analyse financial statement (annual report) of any company?
As a non financial background ,what is the best way to analyse financial statement (annual report) of any company? Thanks
I agree with Esther. Its easy enough to CALCULATE the ratios from the annual report - it needs considerable experioence, knowledge of business, understanding of the particular industry and understanding of accounting standards. Financial analysts get paid big bucks because they know these factors plus they have access to the companies.Following
- NewWhat dose it mean once the P value was greater than 0.05? Does this mean the null hypothesis is accepted ?
Once there were no significant differences and p value greater than 0.05
Does this mean the null hypothesis is accepted ?Following
- 7Do molecular biologists use the term 'substitution rate' consistently, when discuss the calibration of a molecular clock?
In a molecular phylogeny of fishes produced using a cytb marker of 704 bp, Sota et al. (2005) (http://www.ncbi.nlm.nih.gov/pubmed/15684588) calibrated an ML clock tree with a node corresponding to the MRCA of two lineages that are assumed to have diverged in allopatry for 3.5 million years.
The 'node height' of this calibrated node is 0.047 (in Fig. 3, illustrating the ML clock tree, 'node height' apparently = number of substitutions per site).
The authors state that the calibration resulted in a "substitution rate of 2.7% per million years". Later on, they state that "3.5 million years corresponds to 9.4% sequence difference, giving a molecular clock of 2.7% per My".
I suppose that: 9.4/3.5 = 2.7 ...
The node height (0.047) should in fact be the branch length, or the number of substitutions separating the MRCA to one of the two sister lineages, divided by the length of the sequence (704), that is, the (average) number of substitutions per site. In this case, the 'divergence' between the two sister sequences should be twice this amount (the number of substitutions per site between the two sequences, along both branches), or 0.094.
By dividing the divergence (0.094 or 9.4/100, or '9.4%') by 3.4 million years, the authors found a 'divergence rate' of 2.7% per million year.
This however is referred to as the "molecular clock", or the "substitution rate".
Indeed, many authors (including me) would in this case use the term 'substitution rate' to indicate the average number of substitutions per site between the MRCA and one of its descendants, that is 0.047/3.5 = 0.0134 per million year, or '1.3% per million year'.
(incidentally, it always puzzled me why this complication of the '%', which should correspond to a 'rate per 100 million years').
When Sota et al. (2005) compare their "fish cytb molecular clock" of 2.7% per million year with the estimates of different studies (Orti et al. 1994; Cantatore et al. 1994), they find a range 0.8-2.8% per million year that is perfectly compatible with both the 'divergence rate' (2.7%) and the 'substitution rate' (1.3%) calculated above ... a misunderstanding of these rates is obviously very easy, since it is entirely possible that these other authors reported 'substitution rates', and not 'divergence rates'.
I'd be happy to share your thoughts about this topic.
- 12Can anyone recommend some pressure insoles for gait analysis in adults?I need wireless pressure insoles for a study of gait disorders on elders.
Hi, I am also looking for wireless insoles with inertial and pressure sensors. Please let me know if you have already found it. Kind regards, ArifFollowing
- 20What role you visualize for teachers given the onslaught of digital technologies?
Various disruptive technologies have affected teaching learning process. . In view of this , can we contemplate role for teachers, especially in higher education? He/she should be a coach, facilitator, technology savvy etc. What else can we visualize?
The role of teacher in the digital age is less about content knowledge delivery and more about building student competencies and self-efficacy, facilitating peer instruction and ubiquitous learning, and assessing learning outcomes. There is far more content knowledge in students' mobile devices than in their teacher's head!
That said, people learn from people. I am often surprised when students thank me for explaining something that they could easily have read for themselves, or that they did read but did not understand until they heard it explained.
Technology is facilitating a new style of teacher-student interaction and formative assessment. Instead of pausing in a lecture to ask "any questions?" and waiting for the silence to end, teachers can monitor student learning in real time and tackle misconceptions on the fly. For several years, I have invited students in my large (>350 student) intro astronomy classes to ask questions via SMS texts which I read on my phone or smart glasses. They ask ones that they would never ask by raising their hand!
Recently, I have used Learning Catalytics for interactive classes, both on site and online. I can address any student by first name and I constantly send questions out for students to respond to by typing, tapping, or drawing on their mobile devices. Most importantly, I see student response statistics in real time and can resend questions for group discussion when in the peer-learning range (cf Eric Mazur). Students are automatically introduced to their neighbors for discussion, breaking the anonymity of large gen ed classes.
Teachers are not going to become redundant any time soon, but lecture halls and lecturing may well go the way of the chalk board—and it's about time! Technology can deliver content but can't train students how to do research, which is the fundamental role of the university. So modern professors must (1) teach students how to do research (which entails doing research themselves) and (2) research how to teach students (which not enough professors do).Following
- 4Can anyone tell me the name of this ring-type fauna attached to Turitella whorl?
These two species .....I got from near to a river mouth.
Entièrement d'accord avec ce qui a été dit ci-dessus. Il s'agit d'une base de Balane (basis of a barnacle which had calcareous basis. All have not. ) See not far from Balanidae Yves GFollowing
- 3How to compute the correlation/association of quantitative parameters and qualitative criterion ?
I have to compute the association/correlation between texture parameters and the patients clinical covariates (age, BMI, sex and pathologie grade).
For the age and BMI, a simple correlation does the job, but I'm a bit lost for the Sex and grades.
Should I use logistic regression for the sex and Spearman's correlation for the grades (using the grades as proper integers) ?
I would not look at these correlations independently. I would use a (single) model to predict the texture based on age and sex and BMI and pathology grade. You can then see how much of the variation in the response is explained by any of these predictors over and above all other predictors, or, better: how much the prediction intervals are influenced by each predictor (given all others are considered). Such models will use a dummi-coding for categorical predictors. Ordinal variables (like pathology grade) will als be coded as simple unordered categorical variables, so this is a bit suboptimal. There exists no method (I know) to make use of the ordering information. A possible work-around would be to code the levels numerically, but this can also be tricky and have undesired side-effects.Following
- NewWhat is the correct german translstion of "hand proper"?
Does "hand proper" only include the matacarpal bones or also the carpals?Following
- 2Potentiostat and Dr. Bob's cell for small-scale SIMPLE electrochemistry RedOx Reactions?
Our chemistry department just acquired a Gamry Interface 1000 for electrochemical detection. We also bought a Dr. Bob's cell to start learning how to use the potentiostat. I want to know what simple RedOx reactions I could try with this cell just to get a sense of how the potentiostat and the electrodes work. Any help will be really appreciated. Thanks!thank you so much!Following
- NewClinical Phase II to Phase III failures in oncology?
I am requesting the help of the RG community to provide me with recent (no older than 5 years) articles (from very high and only from very high ranked journals) clearly
1) indicating how many and
so many positive Phase II clinical trials in oncology die during Phase III.
I am quite new on RG ... but I already saw that "several" RG members are responding to questions like mine "why are you not making your biblio search by yourself ...".
I did it but I am not convinced at all that I actually have the best articles in this field.
Thank you for your time and attention.
- 4How to calculate Gradient and smoothness regularization operators for geophysical inversion on unstructured grids?
Gradient operators are required for powerful inversion regularization schemes that allow for the incorporation of geological information. i have seen many paper to calculate these operators on rectangular domain . is there any paper to calculate Gradient and smoothness regularization operators for geophysical inversion on unstructured grids?
I think your question is leading to the difference between gridding the data (for later use) or solving the equation that describes the data. If you have the equation you don't need the grid. For examples see the work of G.R.J. Cooper, School of Geosciences, University of the Witwatersrand, Johannesburg 2050, South Africa - and others.Following
- 72How should / could we improve the Educational System, to adapt modern times, and future generations?
Most would agree that Education plays a fundamental role in solving many of the humanity's current problems.
I believe in a better World.
Mass education for all youngster can play a good role in the near future.
Should we change our system?
Should we act on University level?
Should we act transversally from kindergarten, through basic education?
I should like your valuable contributes.
Which countries must do more to help children who fall behind at school?
Gijsbert StoetReader in Psychology, University of Glasgow
Many of the world’s leading economies can do more to help struggling teenagers to get a better level of education that will equip them for later life. A new report from the Organisation for Economic Co-operation and Development (OECD), looking at why low-performing students fall behind at school, has found that much remains to be done to reduce the number of children that perform poorly in maths, reading and science skills.
One of the most striking aspects of the report is just how many children are low performers, even in highly-developed nations such as the UK, Australia, or the US. I find it shocking that one in six children in the UK has a low level of reading comprehension skills – 17% of those tested in both the UK and US, and 14% in Australia.
The new report is based on data taken from the OECD-funded Programme for International Student Assessment (PISA), the world’s largest and most influential educational survey. It aims to raise educational standards by providing detailed information about successful and less successful educational systems.
Every three years, 15-year-old children around the world take the two-hour PISA test. It focuses on some of the most fundamental academic skills: reading comprehension, mathematics, and science literacy. The new report is based on the 2012 PISA round, in which nearly half a million children participated.
The average score in OECD countries for each skill is around 500 PISA points. For example, in the UK, children’s scores in reading comprehension ranged from 121 to 788 points, with a national average of 499 points. Low performance is defined as a score below (approximately) 400 PISA points. According to the OECD, a low performer does not have the skills required to participate fully in a modern society.
The numbers of low performers in mathematics are worse than in reading – 22% in the UK, 20% in Australia and 26% in the US. Of course, it is possible that a child is a low performer in only one of the skills, but the numbers of children performing poorly in all of the three skills is still worryingly high: 11% in the UK, 9% in Australia, 12% in the US and 13% in France.
Which countries do best
There are considerable differences between countries. Those that generally score highly in PISA are, unsurprisingly, also the countries with the fewest low performers. Generally, East Asian countries and economic regions are successful in PISA (with the Chinese cities Shanghai and Hong Kong leading the league table) and have relatively few low performers. But there are European countries that have a similar level of success. For example, Estonia has one of the highest PISA scores in Europe, and only 3% of children are low performers in all three skills, leading the European league table.
There are no simple explanations for why some countries do better than others – many factors play a role. These include the educational levels and income of parents, their engagement, and whether or not children live in an urban or rural area. We should not only look at the leaders of the league table, but also at countries which are culturally and geographically similar.
Take Ireland, for example, which has 10% low performers in reading and 17% in mathematics and has seen a considerable reduction in low performers between 2006 and 2012. In Ireland, only 7% of low-performing children skipped school at least once in the two weeks before the PISA test, compared to 27% in the UK and 45% in Australia. Ireland’s data also shows a lower level of segregation by educational achievement. Such comparisons suggest that dealing more effectively with truancy and a more equal distribution of low performers across schools might help to drive down the numbers of low performers in other countries.
Gender gaps persist
This new OECD report also reports gender differences among low-performers. From other research, we already know that boys fall behind in education around the world, and in the UK in A-Level and GCSEexams. In particular, boys fall behind in reading, and girls, to a lesser extent, in mathematics.
Gender gaps at age 15. OECD, PISA 2012 Database
These gender gaps are also reflected in the new report. As the graph above shows, more boys than girls are low performers in reading and science, whereas more girls are low performers in mathematics. Policies aimed at reducing gender inequalities have so far not been effective in resolving these gaps. A new approach is needed.
One of the problems that the report does not address is that countries with a larger mathematics gap often have a smaller reading gap and vice versa. This is enormously challenging, because some of the countries, such as Iceland or Finland, that are able to eliminate the mathematics gap affecting girls, have a particularly large reading gap affecting boys.
How to raise achievement
The final chapter of the report lays out a series of policies to tackle low performance levels. It gives examples of successful approaches, which include language training for non-native speakers and improving the quality of pre-primary education, which has happened in Germany. It also suggests that schools could foster high academic expectations, and use networks of schools to disseminate best practise.
It concludes that the percentage of low performers in any country can be reduced within a couple of years, if government is willing to reform the education system. While the number of low-performing children in the OECD is disappointingly high, with the appropriate educational reforms, based on evidence, a lot can be done to improve the situation.Following
- 22Architecture for autism. Who has sources for empirical and/or effect research ?For the last three years I've been trying to find out as much as I could about architectural adaptations to better accommodate people on the autistic spectrum. I've learned a great deal from professionals in The Netherlands who were involved in designing and building treatment facilities. On the other hand there's a growing body of literature around this topic. Some of the most important articles are to be found on http://www.ud-da.eu/information_nav.htm, Mostafa, Humphreys, Whitehurst and Scott have made key-contributions, so have the British architect Beaver and Khare & Mullick who have, like Mostafa proposed a matrix of design principles. Hendriksen & Kaup (2009) (http://www.kon.org/urc/v9/henriksen.html) constructed matrixes of classroom design, drawing from literature which was partly new to me. Until very recently my impression was very little research had been done. “Advancing Full Spectrum Housing: Design for Adults with Autism Spectrum Disorders” by Sherry Ahrentzen and Kim Steele, however made me doubt this. (Their work is part of a larger project by the Urban Land Institute Arizona, Southwest Autism Research & Resource Center and Arizona State University.)
Now I started a quest for effect research, testing one or more design principles which were published over the past 6 or 7 years. Many seem to work in practice, but I’ve not come across any rigorous tests [with the possible exception of Mostafa’s (2008) classroom-measures where the number of children was inversely related to their extremely impressive effects.]
The context may be education with which most articles seem concerned, but can also be (semi) independent living (Ahrentzen & Steele) or any other, including treatment facilities of any degree of ‘intensity’.
Ultimately I’ve come to believe there’s a limited number of motives behind design recommendations. My hypothesis is there are basically three: 1) the senses, 2) specific autistic phenomena such as (most notably) central coherence and 3) social difficulties which can partly be remedied through design.
The main principle behind all this is basically the same as is behind many other measures around people with ASD: they can learn to a certain extent to adapt to the 'neurotypical world', beyond which the environment has to adapt to them. ‘The environment’ is usually taken to mean the social environment but should include the physical and the built environment as well. My working hypothesis is that physical measures can be just as effective as most therapeutic ones and combinations of the two even more.