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  • Adam Kelly added an answer in Massage:
    Does massage help blood lactate clearance?

    Is massage the best form of recovery when wanting to clear blood lactate?

    Adam Kelly · University of Miami


    Here are two articles that found that massage had no effect on blood lactate concentrations following high-intensity exercise. Additionally, I think the best evidence available now is that blood lactate is not what causes delayed onset muscle soreness or fatigue with high-intensity exercise for that matter. I also believe most blood lactate is cleared within about 30 minutes of exercise.

  • Why are plant meristems always virus free ?

    When plant breeders want to re-generate plants that are virus-free using asexual multiplication (in order to obtain clones of the primary unhealthy plant), they often collect the apical meristem from the infected plant, and cultivate it in appropriate media, so that a new, complete and virus-free plantlets develop. The fact that viruses spread systematically in the whole plant except the meristems when they colonize a new plant host, via phloem vascular element, is well known. But nothing is said about the putative molecular and cellular mechanisms that allow the pluripotent cells of the meristems to stay uninfected. Do you have some clues about this issue, or does this still remain a complete mystery of plant virology?

    Paulo Ernesto Meissner Filho · Brazilian Agricultural Research Corporation (EMBRAPA)

    Dear Hervè!

    A recent paper about this topic: 

    Citrus leaf blotch virus invades meristematic regions in Nicotiana benthamiana and citrus


    MOLECULAR PLANT PATHOLOGY (2013) 14(6), 610–616

    Sincerely yours,


  • Glenn E. King added an answer in Chimpanzee:
    Do you know of reliable estimates of the amount of meat consumed by chimpanzees?

    I was wondering if anybody could point me towards published estimates of how often and how much chimpanzees consume meat? I was also wondering if anybody had data on how many party members typically consume meat after a hunt (i.e., between how many individuals is a single carcass usually shared)? Information from multiple sites with different group sizes would be ideal! Thanks and all the best,


    Glenn E. King · Monmouth University

    Addendum to my answer: More precise figures can be found on page 65 of the Nishida book.

  • Raju Chowdhury added an answer in Porous Materials:
    Do i solve the following problem using the Brinkman Equation in COMSOM 4.3?

    Please see the attached image. Here I am not clear about the term ∇.(∇u)T. When T is using as superscipt/power of the term, what does it mean? How can calculate the term? Does it mean transverse? Also I am confusing about the term I. What does it mean?

    Raju Chowdhury · Stamford University Bangladesh

    Robert J. Low,

    Thank you very much for your valuable comment and suggestion. I guess that it would be a transpose matrix. If I want to make vanish only this term from the equation what should I do?

  • Why in the exploratory factor analysis, Gradual slope does not appear??

    Why in the exploratory factor analysis, Gradual slope does not appear??

    Did I do miscalculations??

  • Ivan Iudice added an answer in Algorithms:
    What is the relationship between throughput and BER?

    Using the map decoding algorithm I got the result about BER vs Eb/NO. From this how can I calculate throughput? Is there any relationship between throughput and BER?

    Ivan Iudice · CIRA Centro Italiano Ricerche Aerospaziali

    Throughput strictly depends on the source. If source doesn't fill all channel capacity you've not the maximum efficiency of the link. If you want to evaluate the throughput of correct received bits, under BER constraint, you can simply use:


    where R is your source bit rate.

  • Can we visualize caspase-8 on a western blot in non-treated cells?

    I've grown different cells wanting to assess caspase-8 levels in the whole cell lysate. I haven't treated them with anything. I'm unable to visualize caspase-8 in a western blot. What might be wrong? do i need to treat the cells to visualize caspase-8? 

    Ganesh Satyanarayana · Georgia State University

    i'm running a panel of cells, for example HUVEC, PC3 and so on.. all have decent caspase 8 levels

  • Marc Tessera added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.


    What is your definition of a troll when applied to a question?

  • Jing-Huan Wang added an answer in Cell Culture:
    How do the bubbles in a cell culture medium affect the cell behavior?

    Hi, all,

    There are plenty of bubbles on the surface of cell culture medium in my experiments. I cannot get rid of these bubbles because the whole system was continuously gassed with CO2, meaning the bubbles are produced all the time. 

    It seems that the bubbles don't have severe bad effects on microscopic imaging of the cells. But I don't know whether these bubbles will affect the cell behaviour, the cell proliferation etc. 

    Any of you have any comments on this?????? Many thanks in advance!

    another question: how to get rid of these bubbles?????? If I could get rid of these bubbles, that would be perfect then. Any one knows anything?????? Thank you :)

    Kind regards,

    Jing-Huan :)

    Thank you  Subramanian, I agree with you the bubble burst can affect cells. In my application, the medium is flowing all the time, so the bubble burst effects might be minimal? I guess. 

  • How do you remove DMF without using a vacuum pump ?

    DMF is a solvent with a very high boiling point. I want to know how to remove DMF without using a vacuum pump.

    Brooke Anderson · University of Idaho

    In my experience, DMF is slightly more soluble in DCM than in EtOAc so I always extract with EtOAc (if the mixture is soluble).  I run an extraction by first diluting with excess EtOAc, then wash with sat. aq. brine (2X) followed by washing with H2O (2X).  Do not vigorously shake the sep. funnel, but slowly invert it a coupling of times to mix or an emulsion can form.  If the reaction was run with a base (e.g. DIPEA or Et3N), I add a single sat. aq. NaHCO3 wash after the brine wash and before the water wash.  Another point to be made here is to never back-extract your aqueous layer with more EtOAc, it will pull more DMF into your organic layer. Hope this helps and good luck!

  • Could anyone recommend a researcher, or a center, studying technology as an agent of social transformation towards sustainability?

    It is for doing a postdoc. I like modest proposals who puts society first, a cross between engineering and social sciences for sustainability.

    Anne M Cafer · University of Missouri

    PSU also has a Humanitarian Engineering and Sustainable Entrepreneurship program you might find interesting!

  • Does anyone know of cases in which an non indigenous species shows differences in the reproductive biology when compared with the native population?

    Some non indigenous species when reaching a territory outside their native distribution range are able to settle down and establish self sustaining reproductive populations, some non indigenous species however are not able and with time got extinguished in the new territory. I'm trying to find examples of non indgenous species that got established and have developed in the receiving territory reprodutive traits that are different from those native populations and source population present in the native range.

    Alexandra Richter · University of Oviedo

    Thank you very much for the information, Ivan. Which is the invasive species there in South America? I will try to find some articles about the subject, if there is anything published about these invasive salmonids in South America. I work here in Spain with a slipper limpet which seem to altere the mating system.

  • Victoria Bellotti asked a question in Wills:
    Student website overhaul?

    I am trying to find a professor with HCI/UX design students that might be willing to take on a timebanking (i.e. non-profit 501(c)(3)) website (with 24,000 users) overhaul as a class design project?

  • Lukasz Plociniczak asked a question in Einstein-Cartan:
    What is the present status of the Einstein-Cartan theory of gravity?

    This theory has a very interesting flavor, namely it does not assume that the connection on Semi-Riemannian is torsionless. This leads to a very interesting regularization of the Big Bang singularity and also provides a very elegant alternative to the inflation.

    What do you think about this theory and its place in physics?

  • Jochen Wilhelm added an answer in FC:
    How is a t-test on fold change calculated?

    How does one determine whether a fold change calculated on qPCR data using 2-ΔΔCt method is significant? Answers provided to a similar question earlier indicate that one should do a one sided t-test on logFC. How does one go about this? Are there other methods to determine whether the FC is significant? Does one need to report the significance when reporting fold change? Your suggestions will be highly appreciated.

    Jochen Wilhelm · Justus-Liebig-Universität Gießen

    The logFC can be tested with "standrad methods" like the t-test.

    The decision between one- and two-sided depends on what direction of regulation you would find interesting. If you want to find out if a gene is regulated and either direction would be a "hit", then a two-sided test is in place. If you use the test only to confirm a regulation in a particular direction, then a "statistically significant" regulation in the "wrong" direction is considered a "false positive", so in this case the null hypothesis will never be rejected (and thus never be wrongly rejected) when the direction is wrong. Therfore, the nominal type-I error rate will be kept with a one-sided test.

    Are there other methods? To test the expected value of the logFC? No. Not really. Only the t-test does this (and a randomization or bootstrap test on the mean logFC). Other tests test different hypotheses. One can think of plenty different kinds of hypotheses, and each one will have at least one test (or one can design a test for the purpose).

    Does one need to report the significance? Well, why did you do the test? I suppose that has some rationale... and if so, one should expect that the appropriate result is reported. According to Neyman, reporting the decision is enough. According to Fisher, the author should provide at least the p-value (actually also the statistic and the degrees of freedom).

    If the test is not central, it is usually good to provide the confidence interval for the estimated logFC (or for the FC, if you wish).

  • Giulia Barbreschi asked a question in Exoskeletons:
    Power requirement for fuel cell wheelchair/exoskeleton?

    My PhD project is going to investigate the possibilityes for the design of an hybrid between a wheelchair and an exoskeleton powered by fuel cell. I was interested in knowing what would be the parameters of this two motors that I would need to know in order to substitute the traditional power supply (battery) with a fuel cell (likely coupled with a supercapacitor).


  • Razeen Davids added an answer in REDCap:
    How do I set up REDCap for capturing adverse events in a research project?

    I'm using REDCap for the first time and wanting to track peritonitis episodes in patients on peritoneal dialysis. These may happen multiple times per patient. There are no strictly defined visits (as there would be in a clinical trial) and there will be indefinite follow-up - I'm therefore using the traditional, and not the longitudinal, REDCap setup.

    I'm thinking that I should have a new/different data entry form for each episode of peritonitis e.g. episode1, episode2, etc. This just feels very clumsy though so I would appreciate any other suggestions.


    Razeen Davids · Stellenbosch University

    Thank you, Suzanne and Hendrick, for your very useful comments.

    For now, I have decided to start with 10 separate but identical forms for peritonitis episodes and will see how this works.


  • Yoilan Fimia-León added an answer in RefWorks:
    Why does RefWorks sometimes duplicate indexes and how can that be avoided?

    For arranging my references in papers and in other documents I use in reference manager RefWorks. But sometimes, after inserting some additional reference, it suddenly duplicate indexes.

    For example, before inserting additional reference [45-58]. after inserting it look something like that [54, 55, 55, 56, 56, 57, 57, 58, 58, 59, 59, 60, 60, 61, 61, 62, 62, 63, 63, 64, 64, 65, 65, 66, 66, 67, 67, 68, 68, 69]

    Is there is a reason for this? How I can avoid or fix that?

    Thank you in advance.

    Yoilan Fimia-León · Central University "Marta Abreu" of Las Villas

    if you have any question about how to migrate to Mendeley you can take a look at

    English version: http://www.elsevier.com/__data/assets/pdf_file/0007/197476/mendeley_migration_document.pdf

    Spanish version: http://elseviermexico.com/pdfs/3307_Mendeley_Migration_Document_ES.pdf

  • Stephen Joy added an answer in Flexibility:
    Does anyone know of any measures to assess cognitive rigidity or inflexibility of thought as opposed to behaviours?

    I have tried to access the flexibility scale of the CPI but with not much luck. I have the Need for Closure scale and and Personal Need for Structure but just wondered if there is a scale which taps cognitive rigidity?

    Stephen Joy · Albertus Magnus College

    I can make a couple of suggestions, though I'm not all that familiar with all of the instruments in question. I also think you should make a distinction between actual tests of cognitive rigidity vs. flexibility, on the one hand, and self-report measures on the other hand. The latter may be measuring personality traits related to rigidity, or be self-assessments of rigidity, but won't directly evaluate whether the individual is rigid.

    One possibility is Oreg's Resistance to Change Scale. Here is the basic reference: Oreg, Shaul. Resistance to change: Developing an individual differences measure. Journal of Applied Psychology, Vol 88(4), Aug 2003, 680-693. I'm attaching a file that contains the items & scoring instructions. It's a self-report measure.

    A classic approach would be to use a divergent thinking test such as the Alternate Uses test. There are several versions of this around, and you can always create your own. The basic idea is simple,. The test-taker is presented with a common object (such as a brick, a coat hanger, or a sheet) and instructed to think of as many ways as possible in which said object could be used. Usually you'd want to include 4 - 6 items. Responses are scored for fluency (how many), originality (how unusual each response is in the sample, or in the norms if available), and perhaps flexibility (how many different categories they fall into). You can do similar things with more complex stimuli. Rigid people will provide few responses & they will be stereotypical. Really, lots of creativity tests could work for you - just reverse-scored, so to speak.

    Jennifer Gottlieb developed an Alternate beliefs measure for a study of patients with schizophrenia undergoing cognitive therapy. It presents a number of scenarios (such as "you see a man carrying boxes out of an apartment") and asks for as many explanations as possible. She is at Boston University's Center for Psychiatric Rehabilitation. I don't know her, but she would probably be happy to share the measure with you.

    I think there are lots of other possibilities out there. Probably many of the executive function ("frontal lobe") tests would work too - just use perseveration scores. Much depends on the nature of the population you're studying (e.g., kids vs. young adults vs. elders, patients vs. "normal," etc.).

  • Jerrold (Jerry) Heyman added an answer in Hadoop:
    What are the recommended Hadoop versions?

    I know Hadoop Cloudera and Hortonworks. Are there other Hadoop versions you can recommend? And,  do we need to buy these products? Or are they open source?

    Jerrold (Jerry) Heyman · EMC Corporation

    Another that comes to mind is MapR (see http://www.mapr.com)

  • Do you think Domestic violence is still a serious concern in developing Counteries.?

    If so, role of public health experts to reduce risk of this medico-social problem.

    Pablo Ruiz-Rudolph · University of Chile

    I feel it is a largely underresearched area....

  • Lawrence Margulies added an answer in Detectors:
    Why high-resolution EBSD detectors are still often preferred?

    Since several years so-called fast EBSD detectors are available. They mainly deliver a higher speed because of a clearly smaller native image size of the used camera so that the read-out time and the on-chip binning time is significantly shorter. This means, although the same interface for High- and Low-Res cameras is used, the  different transfer rate for images of the same size (e.g. 160x120 pixels) is mainly controlled by the preprocessing on the chip. This trick increases the speed for a camera with VGA-resolution by a factor of 5 and more, in coparison to a High-Res camera. Although EBSD patterns are physically not that sharp, and practically patterns are always binned down to create orientation maps in a minimum of time, why EBSD detectors with a higher native resolution but remarkably slower speed are still the preferred detectors? Especially when speed is often declared as - but finally obviously not - an important driving force...

    Lawrence Margulies · University of Guelph

    I imagine it is only a matter of time before they are used for EBSD since they will provide greater speed and signal to noise. It is not a hardware problem for dealing with unbinned high resolution images but a software problem. I'm sure someone is working on software to use the added information efficiently (after all the spatial resolution of your detector determines the angular resolution of your orientations). With solid state hard drives you can transfer and store at a much faster rate than you would ever practically want to acquire images at. Already there are 4k CMOS chips available, and I'm sure it would be long before we get 16k.

    At 30 fps the orca flash4 can transfer over half a million images (unbinned) via a USB 3 link to a solid state hard drive! It would take a little less than 4 1/2 hours before you reached capacity on a 4Tb drive. Obviously this is not the bottleneck. As usual it is the development of analysis software which is written to deal with the ever increasing density and of information which can be measured.

  • Ganesh Satyanarayana added an answer in RIPA Buffer:
    What volume of the mixture of protease inhibitor + Ripa buffer is used when harvesting protein?

    cell culture experiments

    Ganesh Satyanarayana · Georgia State University


    Normally i use a 10x ripa buffer, diluted accordingly. generally i use around 5-7 microlitres for a final volume of 100 microlitres. practically, there is no hard and fast rule as to how much you should add, you can just optimize it on the fly.

    hope it helps,


  • Allah Bakhsh added an answer in Hall effect:
    Can Hall Effect (HMS-5000) measurement system be used for Nano-structures?

    I have synthesized CdZnS semiconductor nano-wires on ITO substrates, is it possible to measure carrier concentration and mobility through Hall Effect HMS-5000 system because it assumes that thin films are uniform while nano-structures are wool like.

    Allah Bakhsh · National University of Science and Technology

    yes i used gold layer as seed to start nano structure growth. thanks for comments. 

  • Zimu Zhou added an answer in Anodization:
    How can I connect wires with aluminum substrate when doing high voltage anodization ?

    When doing oxalic anodization, I used silver paste to paste wire and aluminum substrate. However, phosphoric acid anodization requires much higher voltage. Wires would burned in this condition.

    Zimu Zhou · University of Massachusetts Amherst

    Thank you Prof. Muralidharan and Dr. Salerno

    I do agree with that it is because of high current. I am now preparing a whole piece of cooper to increase the contacting area of the Al piece. The actually burned point was the wire.

  • Brandon A. Munk added an answer in Bioacoustics:
    In clades that duet, why does one species or subclade lose their duet?

    And more broadly, are there some good cases of bioacoustic signals being lost where the reason for the loss is well-studied?

    Was it a loss of a trait or a failure to evolve that trait? For example, in long-tailed manakins its thought that dueting is an example of an extremely derived trait due to intense female selection. The trait did not evolve in non-dueting manakin species because of differing selective forces. I am not aware of an example where dueting was thought to have been lost. I'd love to hear of one if someone knows of an example. 

  • Rajaa Majeed added an answer in Use Cases:
    What wavelength can be absorbed by the blood?

    I need  to use a laser to measure the percentage of sugar in the blood directly, and I want to know which wavelength can be used in this case?

    Rajaa Majeed · Dijlah University College

    You can used lasers in the range ( 8 - 12)um which are the best absorption for glucose molecules.

  • Avin Koh added an answer in Primer:
    Is it bad if the strongest folding Tm (secondary structure) of my primers are closely similar to that of my primers' Tm?

    Would the PCR reaction be hindered if my primers can form secondary structures at a temperature that is close to the primers' melting temperature? Since the temperature difference is small, the secondary structures could probably form even before the annealing temperature is reached (assuming the Ta is 5°C below the Tm).

    Avin Koh · Universiti Tunku Abdul Rahman

    I didn't calculate the Tm of the secondary structures. Rather, it was an extra bit of info that came with the parcel containing the oligos. dG is -1.46.

  • Gert Nolze added an answer in Indexing:
    Why cubic phases are assumed to be easier to index than lower symmetric phases?

    In EBSD a common believe exists which claims that cubic phases are easier to index than phases of lower symmetry. Since only the (precalculated) interplanar angles are used - except of the optional band widths which remarkably reduces the indexing speed - why an indexing should be more complicated for low-symmetry phases? On the other hand, for cubic phases many angles are equal. Is a discrimination of the concerned planes even more problematic for cubic phases which causes the well-known pseudo-symmeric orientation solutions?  

    Gert Nolze · Bundesanstalt für Materialforschung und -prüfung

    Dear Simon, I don't talk about identification or lattice parameter determination. There you are (probably) right. In EBSD you KNOW the phases (better: you need to know), so that the calculation of any angle might take a bit longer but you need to do it only once...before the measurement. Therefore my question: What should be more difficult since the entire indexing is only based on  the comparison of experimentally extracted angles and theoretically calculated derived from the phase description. Nevertheless thanks for your answer. 

  • Glenn E. King asked a question in Mass Media:
    Is the black bear "fight" recently posted on YouTube really a play-fight between probable siblings?

    Many silly comments are being made in the mass media by news people as well as online viewers. Expert opinion would be welcome.