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  • Haitham Tartor added an answer in Protein Denaturation:
    Urea as protein denaturant?

    Do you know If the urea is quite more efficient than SDS as a protein denaturant?  I always experience a smear in my SDS-PAGE and I thought Urea may help me in getting rid of this smear.

    Haitham Tartor

    Thanks Alejandro, actually that what I was intending to do, the problem is that the MS analysis showed no Ig peptides at all.

  • Abdelilah Bannour asked a question in Pavement Engineering:
    Maintenance strategies of road pavements ?

    Dear researchers,

    I am a young researcher in pavement engineering, I work on the HDM-4 (highway development and Management 4).

    In this context, I try to contact specialists, researchers, etc ..., who work with this incredible tool, and to exchange with them and discuss their experience in the field of maintenance roads.

    Abdelilah Bannour

    Cadi Ayyad University, Marrakech, Morocco. abdelilah.bannour@ced.uca.ac.ma

    (+212 0 677 88 86 05)

  • Jelle van Dijk added an answer in Theory of Mind:
    What is the best test for assessing TOM?

    Some part of my proposal in (M.A) is about TOM , so I need to know any new research about TOM and assessment of it. 

    , I just found " Reading the Mind in The Eyes " (RMTE) , could any one recommend me some better tests?

    Thank you so much 

    sincerely yours 


    Jelle van Dijk


    Do you know of empirical/clinical tests that would detect whether, or to what degree, or in what qualitative different ways, a person is cognitively-socially challenged in interacting socially with others, not in the sense of having a ToM or not, but in the sense of being able to interact socially in the way that Gallagher or De Jaegher's describe it? What I mean is a clinical test based on the 'embodied' frameworks that would actually help therapists (and patients themselves) in treatment, training, therapy, or reorganizing their surrounding lifeworld, so as to get a better grip on everyday social life?

  • Anil Carie asked a question in MAC Protocols:
    Can any one suggest how to simulate congintive radio netwroks ?

    i have designed mac protocol for CR network which use directional antennas, now i need to simulate and see how it works

  • Anton Sigitov asked a question in Data Analysis:
    What application domains use graph visualization for data analysis?

    In particular, I am interested in applications that allows graph manipulation in order to gain new insight into data.

  • Thomas Kearney asked a question in STAP:
    Stap. aureus and E.coli normal and penicillin resistant strains: titration. (beta-lactamase activity)?

    I'm having a bit of trouble trying to discuss the beta-lactamase assay titration results for the different strains and comparing the resistant and normal strains of the same strain. Does a larger titration value mean that bacteria it is more resistant to the antibiotic penicillin? any help in trying to wrap my head around this would be greatly appreciated!

  • Nikhil Donadkar asked a question in Gears:
    Why shift shock phenomenon occurs in lower gears as compared to higher gears in automatic transmission engine ?

    Shift shock is the jolt felt when transmission changes gear. This jerk or shock feeling is observed in lower gear shift (i.e 1-2 or 2-3) and not in higher gears shift (i.e 5-6 or 6-7). What is the reason for such behavior.

  • Smruti Sahoo added an answer in Organic Semiconductors:
    How can we predict the crystal structures of organic semiconductors?

    Is there any software for organic crystal structures design and prediction? Can we do the same using Gaussian?

    Smruti Sahoo

     But Thao P. Nguyen, as I know, VASP is for inorganic crystal structures. Can it be used for organic crystal also? 

  • Jayan V asked a question in Targeted Drug Delivery:
    Whether targeted drug delivery is in use for cancer treatment?

    Targeted drug delivery is very interesting research. Lot of literature available.This technique can be extended to other fields also. Whether this technique is really used in medical field? How efficient and successful? 

  • Laurence Stuart Hall added an answer in Secondary Antibodies:
    Can I re-use the secondary antibody in western blot analysis?

    While I am doing western blot analysis several times, within one week, I am usually using the same diluted secondary antibody solution in TBST 1X buffer for 2 times. Practically, it works with me. However, how many times and for how long can I re-use the diluted secondary antibody?

    Laurence Stuart Hall

    Hi there

    I agree with the above. Secondary antibodies in particular are present in excess to encourage binding (by mass action) so what is sequestered with initial use is a tiny amount of the whole. Furthermore, as already said, storage at 4oC for at least 2 weeks is something I have personally practiced and met with success but for longer storage, either freeze away or for immediate use in the fridge add 0.1% sodium azide (to prevent contamination and yellowing of the milk which does happen over time, although make sure the addition of azide is compatible with your Enzymatic detection !!). Better still simply freeze away

    One caveat regarding freezing however which is the usual protein thing: Long term freezing works well, but multiple freeze thaws can denature antibodies, in the same way other types of protein are denatured

  • Pedro A Reche asked a question in PHYLIP:
    How to obtain confidence values for trees derived from distance matrices?

    I have obtained  distance matrices whose coefficient are related to binding specificity of different molecules. The distance matrices are suitable for the Phylip package and I can get nice trees. However, I would like to have confidence values for the trees.  It seems to me that boostrap will do the job but I could not use the Phylip bootstrap program (seqboot) with a distance matrix. Any help to do this will be greatly appreciated.

  • Jury Gualandris added an answer in Supply Chain:
    Is there any available reference model for procurement in supply chain resilience

    We are looking for any existing reference model  related to Procurement in creating supply chain resilience.

    Jury Gualandris

    Hello Frederic - the list above look amazing, but you can find a more specific reference here:

    "Supply risk management and competitive advantage: a misfit model"


    I've published this paper recently; It focuses on the concept of balanced resilience and on the procurement/supply management practices that enable it; it is full of references that can be of use for you.

    Hope this helps.


  • A. A. Zisman added an answer in Martensite:
    How does the orientation relationship between austenite and martensite variants affect the mechanical behavior of the microstructure?

    It has been claiming that orientation relationship between fcc and bcc phase affects the mechanical behavior.

    Does it mean that the mechanical behavior of the K-S OR is different from N-W?

    It sounds clear that how the packet and block size of the martensite determine the mechanical properties of microstructure. But I could not find any systematic literature which investigates the effect of OR on the mechanical behavior.

    Another question is:

    Is there a unique OR for a specific microstructure? (Considering the fact that in TEM or EBSD, we investigate very small area of the microsture).  For example, via EBSD, generally martensite variants of only one prior austenite grain are studied. Could we say statistically with confidence that the determined OR for one grain is true for the whole structure?

    Cayron has shown recently that there is no unique OR  but there is distribution of OR, which seems quite logical.

    If it is true how we could justify the effect of OR on the mechanical behavior.

    A. A. Zisman

    In this connection (apparent advantage of EDSD for the problem of interest), there are some hints. 1) Roughly limit and outline a field where you hope to find one prior austenite grain (PAG). there are a lot of way to do that... 2) Exclude the rest area, thus making eventual PF noise-free, with standard EBSD options. 3) Obtain the pole figure (PF) where 1, 2  or 3 Bain groups of a single grain may be highlighted: 1,2 or 3 circular clusters (signs of Bain axes) are mutually perpendicuar, whereas each of them has two counterpart rectangular clusters perpendicular to each other and to the respective Bain axis. 4)   Vary the closed contour so that the mentioned Bain groups remain whereas other features disappear. Finally you will get the single PAG.     

  • Abdul aziz Jaafar added an answer in FLUENT:
    How to use UDF under symmetry boundary condition in Ansys FLUENT?

    I'm modelling open channel flows by commercial software Fluent. I've set the surface as symmetry boundary condition, now I want to change the dissipation rate at this boundary,but UDF seems to be unactivated under symmetry boundary condition. How can I realize this idea in Fluent?

    By the way, I also tried to use DEFINE_SOURCE to change the value of dissipation rate near the boundary region, but in Ansys Help Guide, it is said that you can use DEFINE_SOURCE to specify custom source terms for the different types of solved transport equations in FLUENT. I guess the source term is added to the dissipation rate transport equation, rather than the dissipation rate value in certain region. So I think this idea is unfeasible.

    Thank you very much for discussing with me and providing suggestions!

    Abdul aziz Jaafar

    Dear Wu

    Have a look at one equation turbulence model in Ansys.. maybe you can see it for comparisons.. It might be a bit turbulent than two equation models..


  • Karthika Natarajan added an answer in Soil Contamination:
    Where do I get contaminated soil?

    to contaminate soil,what is the procedure?how to add exact amount of contamination?like lead chromium,copper etc..

    Karthika Natarajan

     thank you for all your valuable comments..

  • Pierre Rouzé added an answer in Gene Mapping:
    Which isoform of a gene is a major isoform in a specific population? Is it possible that multiple isoforms present in a individual?

    I think this question maybe helpful for understanding which kinds of variants cause disease. Is there any database?

    Pierre Rouzé

    Hi Yifu,

    If I would basically agree with Salvatore, I would tend for sake of clarity be a bit more specific.

    We used to use the term "isoforms" when referring to the various protein products of the same gene, and to "alternative transcripts" when referring the various messenger (mRNAs) and non-coding RNAs (ncRNAs) which are produced from transcription at the same gene locus.

    Then I will join Salvatore in writing that the same individual may have several alternative transcripts at different times (being seconds/minutes or years), different organ/tissue locations and under different environmental stimuli. Most alternative transcripts are reported to occur independently of each other (i.e. at a given place, a given time and a given environment/stimulus a single alternative transcript will be seen, if the gene is expressed. But the reality is most often that one transcript will simply be dominant with  expression of other transcripts being observed as well, at (much) lower levels.

    Of these alternative transcripts, some being coding mRNAs will lead to various protein isoforms, some other although being also mRNAs will produce no protein at all (e.g. those with CDS severely mutated, with translation ability affected or with very short half-life), last some (many) other will not end up in any mRNA, hence their ncRNA naming, these ncRNAs being nevertheless potential having a biological function per se.

    And, indeed, these variations are often of the kinds which explain the occurrence of diseases in humans, when these diseases have a genetic background,... and of most biological events and species-specific traits in other organisms as well !

  • Felipe Gil-T. added an answer in Butterflies:
    Did artificial diet affect Troides helena female to produce male in their offspring?

    In my research, I just find Troides helena male coming from artificial diet containing red bean, pollen and mung bean sprout. In contrast, natural food produces male and female butterfly. 

  • Xiong Yanshi added an answer in FACSCalibur:
    Has anyone had any technical problems with their Flow Cytometer?

    Our flow cytometer, the BD FACSCALIBUR, seems to be malfunctioning: it won't stop sucking up the sample. Anyone have any experience with this problem/volunteer a solution. I was cleaned less than 1 week ago fully, and functioned perfectly twice before this problem.

    Xiong Yanshi

    I had a similar situation before, but not exactly the same. It was: the machine won't stop even when I take off the sample tube, so the sheath start to flow back from the "sample incoming" pipe because of the air pressure from the pump. I finally realize that when you pull off the sample, two metal wire leave the solution or buffer, which makes  the machine knows and then stop sucking the sample solution. So check the metal wire could solve.

    Maybe can't help you, but good luck!

  • Sandeep Ss asked a question in Perovskite Solar Cells:
    What is the importance of impedence spectroscopy study of perovskite solar cell?

    how impedence spectroscopy can be relate to perovskite layer interface with ZnO(ETL)?

  • Carlos Araújo Queiroz added an answer in Solvents:
    How can I recognize the features of a solvent?

    When we want to use a solvent or a mixture, we want to predict and evaluate different types of molecular interaction through some features of the chosen solvent.

    Like, polar or apolar, protic or aprotic, etc..

     Please help me with reference, book or link, etc …

     I need to write a chapter in my thesis manuscript and use these concepts for discussion and interpretation of the studied liquid systems.

     Thank you in advance.

    Carlos Araújo Queiroz

    Cf.: Ian. M. Smallwood, "Handbook of Organic Solvent Properties", Amold / Hodder Headline Group (London) and Halsted Press / John Wley & Sons Inc. (New York), 1996.

  • Giuseppe Cotellessa asked a question in Telomerase:
    Could telomerase application to human living cells give immortality to men?

    What are experimental results to give demonstration and validity to this hypothesis?

  • Masoud Akbari added an answer in Chemokine Receptors:
    Which chemokines are involved homing and accumulation of the activated CD8+ T cells in liver?

    Hi dears

    I am transferring in-vitro activated CD8+ T cells into host mice IV. 

    They can enter the liver and accumulate around the infected hepatocytes expressing the antigen.

    I am wondering which chemokines and chemokine receptors are involving in the homing of these cells in the liver and their accumulation around infected hepatocytes.

    please if you have any suggestion let me know.

    Kind regards

    Masoud Akbari

    Thank you dear Urs

    Your answer is amazing. I am reading your paper (Breaking tolerance to the natural human liver autoantigen cytochrome P450 2D6 by virus infection). 

    I am looking forward reading your next paper.

    Wish you all the best


  • Farid Faridani added an answer in Soil Moisture:
    Can you name a soil moisture point between Saturation and Field Capacity? How can I define it for different soil textures?

    I have a number of hourly time series of soil moisture. In these time series, TDR never measured values near soil saturation, but my max values were alway at a certain point between Saturation and FC. So I thought maybe there is really a soil moisture point between Saturation and FC.

    Farid Faridani

    I have a number of hourly time series of soil moisture. In these time series, TDR never measured values near soil saturation, but my max values were alway at a certain point between Saturation and FC. So I thought maybe there is really a soil moisture point between Saturation and FC.

  • İbrahim Astarcioglu added an answer in Liver:
    Any suggested protocool to expand liver proginitors cells derived from IPSCs, ??

    Any suggested protocol to expand liver progenitor cells derived from human iPSCs??


    İbrahim Astarcioglu

    Y can ask this question to Yamanaka from Yokohama-Japan

  • Marcin Siwiec added an answer in Oligodendrocytes:
    Is it possible to deplete astrocytes and oligodendrocytes from slice cultures in a pharmacological way?

    We want to culture hippocampal slices and we want to selectively deplete astrocytes and oligodendrocytes without affecting the neurons. We know how to deplete microglial cells and it works more or less effectively. Is there any compound (like clodronate) to deplete these cells pharmacological? We found some papers describing methods but I don't think that they are applicable in our experiments. Thanks for your answers =)!

    Marcin Siwiec

    Since fluorocitrate is often described as reversible, has anyone observed the washout of the toxin in slices? If so, what is the time course?

  • Nurul NAZURAH Atu added an answer in GARCH:
    What is the order for GARCH when my ARCH effect test significant at lag 5?

    1. When I am run arch effect test, the result shows the arch effect test significant at lag 5. Hence,to proceed GARCH model, the order GARCH should be GARCH (5,1) or GARCH(1,1) for the variance and distribution specification ?

    2. My dependent variable is stock returns (srt), and my independent oil price returns (ort). My questions is when I am run the GARCH model, the equation specification should be (srt c ort) or (srt c )?

    Nurul NAZURAH Atu

    Dear Mark , thank you for your responds. Now, I am a bit confuse whether to include the independent variable in the mean equation of ARCH and GARCH model. I want to predict whether oil price can affect on stock returns. My equation is "stock returns(srt) = constant (c) + oil price returns (ort) + errors (e)". Whether I should put in "srt c" only or include independent "srt c ort". Thanks

  • Ana Nikoli asked a question:
    ContrAA 700 AAS

    Could anyone help me to discuss about this figure. What is purpose ?


    Nikolic Ana

  • Waseem Hajjar added an answer in MRSA:
    Do MRSA patients need to be isolated?

    Some of the patients are carriers, and some acquired MRSA through airborne particles.

    Do we generalise both groups by isolating them from patients of other disciplines? If not,why? 

    Waseem Hajjar

    Absolutely, yes needs to be isolated, To prevent MRSA transmission.

  • Pavan Pagare added an answer in Tin oxide:
    Is it possible to flatten the FTO surface on TEC substrates by chemical or thermal means?

    A compact layer of TiO2 is to be deposited on top.

    Pavan Pagare

    make thin film upto nanosize is best way of it 

  • Patrick N.B. Anongba added an answer in Applied Mechanics:
    The bending of a beam by terminal transverse load: what is the relation between applied stress at failure as a function of specimen dimensions?

    Could someone acquaint me with experimental works providing the applied stress at failure of rectangular specimens, horizontally in a wall on one end and vertically loaded at the other end, as a function of the specimen dimensions? We are studying theoretically this problem.

    Patrick N.B. Anongba

    Please see the research paper "A THEORY OF THE FRACTURE OF A RECTANGULAR BAR BENT BY TERMINAL TRANSVERSE LOAD AND COUPLE" in our contributions for details