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  • Alfredo Corell added an answer in MHC
    What is the relationship between MHC polymorphism and fitness related phenotypic traits?

    Does anyone know of any studies that have shown a relationship/correlation between MHC polymorphism and important phenotypic traits e.g. secondary sexual characteristics such as male colour etc?

    I can find surprisingly very little on the topic.


    Alfredo Corell · Universidad de Valladolid


    perhaps you don't find much because it's not too much things to find. I had this evolution paper that probably you knew about mapping quantitative trait loci. I hope this helps you

  • Yves Braet added an answer in Laboratory Equipment
    Does anyone know where we can purchase a CPD machine?

    We are planning to buy a CPD machine to extract tiny flies from alcohol without shrinkage of the specimens. Should you have any ideas about a heavy-duty CPD at reasonable price please send me the related information.

    Yves Braet · National Institute of Criminalistics and Criminology

    May be you can find something there http://www.quorumtech.com/products/critical-point-dryers/e3000-and-e3100-critical-point-dryers.html

  • Frank Larue asked a question in Inflammation
    Nervinervorum cells...

    We now know that nervonervorum cells do produce Substance P and inflammation factors. However, how can we explain the origin of such an autodestructive mechanism. And we now know that their TRVP-1 receptors can be blocked by Dextrose 5% as well as by Capsain! Any further comments on that mechanism?

  • Can implied volatility be used as one of the inputs in the var-covar matrix instead of historical volatility?
    Using the historical var-cov matrix as an input in the optimizer leads to estimation errors. What other methods can be used in estimating the var-covar apart from shrinkage and diagonal methods?
    Arcady Novosyolov · Siberian Federal University

    A standard way of incorporating implied volatilities is using historical correlation structure. That us, denote C the historical var-covar matrix, and HS, IV - diagonal matrices with historical and implied volatilities in the diagonals. Then correlation structure is K = HS-1  * C * HS-1, and the combination looks like CC = IV * K * IV. In all, one can first calculate D = HS-1 * IV, and then immediately get the result CC = D * C * D.

    This approach does not create any math inconsistencies.

  • Can spin-coating achieve a thick (~2 micron) P3HT film?

    I need to deposit relatively thick films of P3HT (at least 2 microns thick.) Is spin-coating a good technique for depositing P3HT films of this thickness?

    Can anyone recommend what speed I would use, or give a reference to what spinning speed gives what thickness of film for a particular concentration of P3HT solution?

    Genesis Ngwa Ankah · Leibniz-Institute for New Materials

    should be possible to achieve that if in addition to spin-coating multiple times, you also reduce speed (rpm) of the spin-coater. The higher the concentration of the P3HT solution, the better. A value for the speed is difficult to guess - I suggest you start with the lowest but reasonable value

  • I am looking for specialists in order to identify arthropods from Djibouti. Can you help?

    For 4 years, I have collected arthropods from Djibouti. Now I need help to identify them.

    Mustafa Cemal DARILMAZ · Aksaray Üniversitesi

    Hello, I can identifiy aquatic beetles (Coleoptera: Adephagan water beetles and Hydrophiloidea)

  • Alak Manna added an answer in Cancer Cells
    For cancer chemotherapy, which is a potential therapeutic: Pro-oxidant or anti-oxidant?

    It is well established that basal levels of ROS is higher in cancer. There are two schools of thought: 1. Pro-oxidant could be a potential chemotherapeutic 2. Anti-oxidant could be a potential chemotherapeutic.

    School 1 says: If one (drug or any molecules) can increase cancer cell's ROS by means of inducing ROS generation or by depleting anti-oxidant or by both ways, it can increase cancer's cells ROS levels beyond critical threshold limits leading to death. It will not hamper normal cells as its basal levels is lower.

    Treatment with Anti-oxidant will strengthen cancer cell's anti-oxidant system, thus will survive more. 

    School 2 says: Anti-oxidant is a good choice as ROS can increase in normal cell with pro-oxidant, there might be malignant transformation.

    Anti-oxidants induce apoptosis in cancer cells and have no harmful side effects to normal cell.

    Alak Manna · Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital

    Hi Dear Tinkov, I appreciate and thank you for your subjective view.

  • Nishant Kumar added an answer in Active Learning
    What is the role of an "Academic Advisor?"
    Is the role of “Academic advising” only limited to increase students’ understanding about the curriculum or beyond this?
    Nishant Kumar · Independent

    The role of Advisor should be show a path and all present possibilities so that they can explore the possibilities and come with New innovative ideas and fetchers. 

  • James R Darwent added an answer in TiO2 Nanotubes
    Does anyone know why the TiO2+ water+ethanol solution becomes purple during photocatalytic hydrogen production?

    I prepared TiO2 nanotubes through hydrothermal method. I used as prepared TiO2 as catalyst for hydrogen production. I added 8mg TiO2 + 6mL H2O + 2 mL ehtanol to the reactor. I kept for photocatalysis by pasing UV light and after sometime the solution became dark purple. This results gave no hydrogen production. after removal of the reactor from UV light the solution became colorless after few seconds. Can anyone give the solution for this?

    James R Darwent · University of Liverpool

    I am sure the above answers are correct, you will produce Ti3+ which is deep blue in colour. The disapparance when the UV light is removed suggests that some oxygen is leaking into your reactor, since the reaction between Ti3+ and O2 is quite fast.  To get hydrogen you will need to add some platinum.  Colloidal Pt would be best and you can prepare it with citric acid plus chloroplatinic acid there are several methods described in the literature. Best wishes.

  • Fawad Niazi asked a question in Piles
    Can anyone help me with references on the topic of pile setup, or long-term gain in pile capacity?

    I am interested to study the long-term increase in capacity for different categories of piles in different types of geomaterials. Right now, I am trying to collect and review all the relevant literature on this topic in order to find if there are any gaps that could be plugged, or some investigations could be conducted towards improved understanding. I found following summary information on this topic. A help in finding the related literature will be appreciated.

    Pile resistance in long-term behavior involves setup and increased capacity over time. Effective stress (or the drained characteristics) governs the long-term behavior of piles, especially in clayey soils, following dissipation of excess porewater  pressures. In addition, ageing and other rheological effects (i.e., pile "freeze", thixotropy) can occur in clays, silts, and sands following the pile installation. Pile setup has two major components: (1) short-term setup caused by the dissipation over time of the excess pore water pressures generated during the pile installation, (2) and long-term setup, i.e., additional gain in strength over time at constant effective stress due to other factors, such as secondary compression (creep), bonding, and/or ageing (Konrad and Roy, 1987; Whittle and Sutabutr, 1999; Svinkin and Skov, 2000; Randolph, 2003; Karlsrud and Haugen, 1985; Schmertmann, 1991; Basu et al., 2013). Basu et al. (2013) indicated that the mechanisms of setup and the setup periods are different for fine-grained and coarse-grained soils, because of the drainage characteristics and other intrinsic properties of these geomaterials that affect the soil-structure interactions and their response to the loading.

  • Lorenz Jenny added an answer in Protein Chemistry
    Can you answer my question about a protein purification protocol?

    Hi there,
    I would like to purify an in CHO cells expressed mutant protein after a protocol I found for the purification of the same protein (prothrombin). Now, as I am not really a protein chemist, I have some issues in understanding the protocol.
    For instance as a first step the lysat is put over a Q-sepharosis column (amersham biosciences) using a hepes/benzamidine buffer. Then all the protein fractions are collected and precipitated with Na-citrate and bariumchlorid, then dyalized and after this it is put over an HQ Poros Column (applied biosciences) again with HEPES buffer, but this time only the prothrombin gets pooled. Now as far as I know, both columns are anion-exchanger columns, so why dont they use the same column for both steps?
    Is there an alternative instead of buying both columns?

    Im grateful for any help!

    Lorenz Jenny · Universität Bern

    Hi there,

    Cheers for all the good answers. So if I understood that right, the first column needs to have a higher particle size than the second one. But approx what sitze would you recommend? I surfed the GE life sciences coulmn page (http://www.gelifesciences.com/gehcls_images/GELS/Brands/HiTrap/28931778AE.pdf) but wasnt able to decide which I should take. Im a molecularbiologist and and Im really lost in this jungle of opportunities.
    I know that it should be big in particle size and that it has to be an strong anionexchanger, but has it to be High pressure? Or fast flow? And what about the highload, highprep, hightrap?
    This all might be stupid questions for you guys... I know

  • Can the DOPE score be used to compare models of different protein sequences using different templates?

    Or is it only used to pick up the best model among many generated by modeller (for example), for a single amino acid sequence?

    Lochna Patar · Assam Agricultural University

    Hi Gayatri,

    DOPE score  is a pairwise atomistic statistical potential which is use to distinguish the "good"  models from the "bad" ones. Lower the DOPE score better is the model.

    So, it is use to compare  models made of the single amino acids sequence.  

    For more detail check the link below:


  • Lucia M. Li added an answer in Homelessness
    Does anyone have experience with pituitary gland injury from IED Blast?

    I am finding low growth hormone levels in OEF/OIF veterans with tbi./ptsd  that have been homeless. This population is very vulnerable because they feel lost around groups of people. Those with mild to moderate TBI are our most difficult challenge because there are no residential programs for this group that would combine both TBI and PTSD treatment programs to support integration. Out- patient treatment is not intense enough and difficult to keep the veteran engaged  they become frustrated with the system so they end up leaving housing and become homeless again. Any thoughts on low hormone level and emotional instability support poor decision making? Does motivational interaction even having any therapeutic affect on this population?

    Lucia M. Li · Imperial College London

    Pituitary dysfunction after brain injury is a well-recognised phenomenon, although the true prevalence and impact is still under research.

    A recent UK study looking at blast TBI in particular appears to support the idea that blast TBI related pituitary dysfunction is linked to poor cognitive function.

    Ann Neurol. 2013 Oct;74(4):527-36. doi: 10.1002/ana.23958. Epub 2013 Sep 24.
    Pituitary dysfunction after blast traumatic brain injury: The UK BIOSAP study.
    Baxter D, Sharp DJ, Feeney C, Papadopoulou D, Ham TE, Jilka S, Hellyer PJ, Patel MC, Bennett AN, Mistlin A, McGilloway E, Midwinter M, Goldstone AP.

  • Angel Del Rey-Mejías added an answer in Box Plot
    Can anyone help me with the outliers test?

    I am working on malicious user detection in cognitive for cooperative spectrum sensing. I need to understand in depth about the dixon test, box plot test, grubbs test

    Angel Del Rey-Mejías · Instituto de Investigación Sanitaria Gregorio Marañón

    Completely agree with Beatrice. 

    Another point is your sample size and number of values to test:

    N<25 Dixon's or discordance test.

    N >25 Rosner or Walsh's test.

    My recommendation is after identify your outliers (i normally use box-plot visual technique), you should study them and reasonably asset if they should be there or not. If they should is statistically robust methods if they shouldn't excluded them but report the reason why they were there originally.

    Good Luck!

  • Nishant Kumar added an answer in Education
    Can a Global-Scholarship be formed for academia?
    During my chit-chats on RG, I discovered a very interesting problem that I didn't know existed before: Academicians from resource-deprived countries can conduct great research, however, they cannot publish their results due to the high costs of prestigious journals' page charges etc. While clearly these journals need to charge these fees to continue operating at the highest possible quality, my question is different: Is it possible that an organization can be formed to strictly allow academicians to publish in these journals, almost like a sort of scholarship? My specific idea is as follows: *** A global organization is formed out of good, volunteering scientists *** The entire purpose of the organization is to allow EQUAL chance to scientists from all over the world, initially strictly for publications. *** The funding for this organization will come from worldwide grants *** The only criteria is the quality of the research and quality of the publications *** If the editorial board, after an initial review, decides that, the quality of a publication is high, it gets submitted to the top journal and the publication costs are covered by the organization. *** Very clearly, this could only work, if the organization is totally uncontaminated with political motivations etc. Is this possible? Or, am I a dummy in thinking too optimistically?
    Nishant Kumar · Independent

    Ya sure ... 

    And this is helpful for all ...

  • Alieh Ameri added an answer in Docking
    Docking Analysis

    How can I count Hydrogen Bond after docking by Autodock Vina through visualizing by PyMOL? Ligand consists of Oxygen, Nitrogen, Carbon and so on. Oxygen of Ligand binds with the amino acids of protein. How can I confirm that Oxygen binds with the hydrogen of amino acids. Expecting experts comments.

    Alieh Ameri · Kerman University of Medical Sciences

    you can see interactions ( H-binding and hydrophobic ...) with auto dock tools. 

  • Huda Abdullah added an answer in Statistics
    Can anyone help with statistical analysis of DNA retrieval methods and potential influence of fabric type?

    I'm trying to statistically compare a number of DNA retrieval methods (n=5), where known DNA amounts were deposited on a number of fabrics (n=5). Ideally, I would like to determine if there is a statistical significance between all retrieval methods and also if one had a certain type of fabric would different retrieval methods from these fabrics yield significant differences? Which statistical test(s) (and post-hoc(s) if necessary) would be of benefit to me? I appreciate any help/advice.

    Huda Abdullah · Al-Mustansiriya University

    Raid, A two factor model with factors DNA Retrieval Method and Fabric Type will not serve her aim because it will compare between the 5 overall means of number of DNA retrieval methods (n=5), each retrieval methods consist of 5 fabric types that is a first factor as you showed. the second factor will be fabric type, the comparison will be between the  5 fabric type each type consist of 5 Retrieval Method. Hence, according to the aim of her study, she should apply one way analysis of variance (ANOVA) to test the significant of differences between  retrieval methods (n=5), in each fabric type. Also she can test the differences between fabric types inside each  Retrieval Method (apply F test 5 times because she have 5 Retrieval Method ).

  • Ramit Singla added an answer in Conformity
    How to selection a conformer of a protein

    I have observed a 50 conformer for a protein by experimental method of NMR solution. How to choose the best conformer for simulation study. 

    Ramit Singla · Central University of Punjab

    I know the binding region of the drug and the essential amino acids participating during the binding, So according to your suggested method I have to select that conformation of the protein in which these essential amino acids will interact with drug.

  • Adam Hughes added an answer in Optics
    A special kind of GRIN media - any thoughts?

    I'd like to find out if it is hypothetically possible to create a refractive index gradient profile so that it bends the light until it gets perpendicular to refractive index gradient and then light propagates forward without being bent down. Please see the attached photo for more description. Thanks in advance for any help. 


    Adam Hughes · George Washington University

    Hmm, I don't know.  My impression is that if you create the first say 1 micron length of the fiber to have a lense-like curvature, it can be done, but is this any better than focusing the light directly with a lense into a standard fiber?  Or do you need the rays to stay perfectly horizontal in the tube.

  • Bipinraj Kunchiraman added an answer in Culturing
    Can anyone suggest precautions to be taken while growing Arabidopsis thaliana?

    We have A thaliana seeds and tried to grow them in normal culturing agar medium and soil. It is now 6 days and we did not get any growth.

    Bipinraj Kunchiraman · Bharati Vidyapeeth Deemed University

    Thanks Martha

    We have followed the cold shock step before sowing the seeds.

  • Potable water is a problem, almost for the entire world so, can chlorine tables are useful for this purpose as a cost effective water purification ?

    Drinking water is a major environmental issue for developing countries as well as rest of the world. so chlorine tables can play important role for water purification in respect of cost effective and availability ? please share your views as for global benefit.

    Thank you all.

    Moharana Choudhury (Roy choudhury) · North Eastern Space Applications Centre (NESAC)

    well sir bacterial contamination in drinking water is a major issue for global concern and chlorine is effective for bacterial presence as  E Coli etc thus discussed about chlorine particularly. please share more info in this regards.

    Thank You.

  • Johannes Gruenwald added an answer in Plasma
    How can we calculate the distance between two charges in the case of plasma

    i want to know the value of the smaller distance between two charges, experimentaly or analytically for plasma.

    Johannes Gruenwald · Karl-Franzens-Universität Graz

    Although Samir has already given a reasonable estimation of the minimum distance, I think you can do even better by looking at the volume of your particles. Each of your particles has an volume of 4/3 r³ Pi (where r is your particle radius). You can lock each particle into a cubic box of volume (2r)³.

    From that you can calculate the rest volume Vrest = V1 - NV2 . Here the first term on the r.h.s is the volume you are looking at - for example, 1cm³ and N the number of particles, V2 being the volume of one particle.

    If you have a high number of particles moving randomly in your volume, the particles should be distributed homogenly over the whole volume. This means that you can divide your rest volume into small volumes V2. From the result take the cubic root and you know for each spatial direction how many empty cubes you have for one "particle cube".

    If you have, lets say, five empty cubes for one particle cube, there will be five empty cubes with side length of (2r) between two particles - this gives you then the minimum distance between them. You don't need to worry about the diagonal distances, because if your particles are equally distributed their diagonal distance will allways be larger than their horizontal or vertical distance (and you are only interested in the minimum distance, as I understand it).

  • Hashem Adnan Kilani added an answer in Heritage
    What can you say, are the advantages and disadvantages of being a country that has been colonized by foreign powers?

    Several countries have been colonized in the past by foreign powers.  Strong naval powers like Britain have added colonies, one of which was my country.  On hindsight, I perceive that there are some advantages of having been a colony.  For example, we have many heritage sights as a result of colonization.

    What are your views on this?  Would you say there are advantages and disadvantages of being a country that has been colonized by foreign powers?

    Hashem Adnan Kilani · University of Jordan

    Yes indeed, there are positive and negative aspects from British colonization to my country Jordan and Palestine. The positive is the basis of development such as education, hospitals, roads, and other institutional regulation. The negative is colonization by remote to politics, such as standing on a side of party than another. This is very clear in Palestine when British colonization stood with Jewish people and gave them the land and weapons while deprive Palestinians from their own land and any kind of weapons. They applied what is known by The Balfour Declaration. (  How granted land not owned, for people who do not deserve it)

    This is the reason for the tragedy of the Palestinian people

  • Nishant Kumar added an answer in Faculty
    "Management as a Profession" What's your own opinion aobut this statement?

    As a faculty member of Management i need to clear about this statement. Would you please answer this question to help me.

    Nishant Kumar · Independent

    Management is not a Profession.

    It is an Art. 

  • Love Kumar added an answer in Network Security
    Is it possible to integrate an optical & and wireless network with NS-3 or NS-2?

    is it possible to integrate optical & and wireless network with NS-3 or NS-2?

    Love Kumar · Punjab Technical University

    thanks tranthe Son ....  Can you tell me any other option the integrate Wireless & optical network

  • Tahir Maqbool asked a question in Forward Osmosis
    How to do COD of high sline water, i am doing research on FO-MBR, which give permeate with high salinty. as in litrature FO-MBR remove above 99% COD.

    forward osmosis membrane bioreactor

  • Gerard R Ridgway added an answer in Peer Review
    What are your thoughts on (and experiences with) open post-publication peer-review?

    There have been several developments related to post-publication peer-review, commenting and/or evaluation. For example, PubMed Commons, PubPeer, Publons (the latter also offering credit for traditional blind pre-publication peer-review), PLoS Open Evaluation, and of course ResearchGate's Open Review. There are also new journals with only post-publication peer-review, such as F1000 Research.

    I haven't seen that much discussion of these developments on ResearchGate yet, so would be interested to hear about people's thoughts and experiences. Have you come across interesting discussions? Do you feel anonymous reviews (e.g. on PubPeer and Publons) are overly critical? Do enough papers get ratings from enough different raters to make evaluation meaningful? How do the different tools/website compare? How could they be improved?

    Gerard R Ridgway · University of Oxford

    Thanks Neslihan, PubPeer's view on anonymity is that "Blind peer review has been employed by most major scientific publications in order to allow reviewers the ability to critically assess the work of their peers without fear of retaliations." Personally, I think there is a place for anonymous post-publication review, but it perhaps needs to be moderated to prevent abuse.

  • Usman Ali asked a question in Viscosity
    Does the static fluid have viscosity?

    Does the water in a bucket have viscosity?

  • What is the main test for validation of prebiotic for a simple food systems ?
    Resistance to ferment.
    Seyed Hossein Hoseinifar · Gorgan University of Agricultural Sciences and Natural Resources

    what do you mean by validation and food system?

  • Frank Larue asked a question in Arthrography
    MRI arthrography under ultrasonography

    What frequency or most appropriate, what are the combined frequencies to obtain the best definition or echogenecity down to 7cm?