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  • Maria Mustafa added an answer in Contact Angle:
    How to determine hydrophilicity and hydrophobicity of a polymer?

    Can someone please tell me, how I could predict whether my polymer is hydrophobic or hydrophiic. Is there a lab method? I know about contact angle but it needs goniometer. Please suggest.

    Maria Mustafa · COMSATS Institute of Information Technology

    You can find the nature of polymer by analyzing the contact angle via contact analyzer machine.

  • Abdelhalim Boukaba added an answer in Baculovirus:
    Have you ever try to perform a PCR from baculovirus solution

    I would like to amplify the cDNA of my protein of interest from baculovirus suspension. Actually, I would like to be sur that a specific mutation is well present...
    Any recommendations ?
    Thank in advance.
    Best.
    N

    Abdelhalim Boukaba · Chinese Academy of Sciences

    First, you cannot amplify cDNA from bacaulovirus you need to do it from the host cell (Sf9). You can check for your mutation by PCR directly from your bacaulovirus solution. I don’t see why not. Colony PCR works well on intact bacteria and several species of yeast.

  • What factors are necessary to consider while designing a nanoparticle-drug cargo tageted for lymph nodes?

    Apart from surface chemistry specific to cell of lymph nodes, how to consider factors like reynold's number, inertial and frictional forces in blood that the cargo would face?

    Lingheswar Sadhasivam · Fairleigh Dickinson University

    When it is a Nanoparticle-Drug combination, every point of 'Lipinski's rule of 5' counts. Dendrimers shoulg go good.

  • How do you determine the mode of action of a hypoglycemic drug?

    I intend to test the drug on mice models of diabetes and the drug i intend to use is an ayurvedic medicine and hence the active component is unknown to me. i do plan to do a chromatographic analysis to separate out its components. but am confused as to what path to follow so as to determine its mode of action.

    Max Stanley Chartrand · Northcentral University

    And I think we will find the old rats dying an early death, just as the humans who take such metabolically interrupting chemicals will die earlier albeit over years rather than weeks while taking it. On a more serious note, a truly worthy scientific experiment of tremendous potential for good is going for enterically released organic substance or extract such as ginger or bitter melon, etc. Most of the drugs we have investigated with were synthetic versions of something natural. The synthetic versions were loaded with terrible side effects, and the natural versions rarely exhibiting anything of a serious nature. Hypoglycemic inducing compounds or substances, like those administering them, should first do no harm, in my opinion.   

  • Does someone know a good sistem for screening "in vitro" to perform selection based on the folding properties of proteins?

    What are the major differences between protein unfolding and misfolding? And how can I pick up the most thermostable proteins?

    Jeffrey R Brender · University of Michigan

    @Lucas "I mean how could I be sure I have a single variant in each well of the plate?"

    You can't, which is the disadvantage of the Thermafluor approach. You need  purified proteins for it to work. To work with a library you need a selection step which limits your options to techniques which have a physical separation process for unstable proteins such as the urea gradient affinity column Adam suggests.

    If the protein does not bind a small molecule ligand, you could try  using hydrophobic interaction chromatography instead of an affinity column (unfolded proteins will bind the column due to their exposed hydrophobic surfaces).  Load the whole phage library into the column in 8 M urea and elute the proteins by decreasing the urea concentration. Same as above, proteins that are more stable to chemical denaturation will elute first. This assumes delta G (chemical denaturation) is at least correlated with delta G (thermal denaturation), which isn't always true but it is extremely difficult to select directly for thermal stability.

    A similar procedure can be used to eliminate misfolded proteins from the library. Load the phage library directly to the column without urea and elute with salt. Misfolded proteins generally have exposed hydrophobic surfaces and will tend to be retained in the column.

  • ANUPAM DHASMANA added an answer in Biotechnology:
    Anybody from biotechnology background?

    I would like to know some info.

    ANUPAM DHASMANA · Indian Council of Medical Research

    yup dear.........what do u wana know

  • Shivika Rai added an answer in Alzheimer's Disease:
    What is the best animal choice?

    For a pharmacological and another pathway study related to Alzheimer's disease (such as those including building animal models), what is the best animal choice? The mice or the rats? If it is the mice, which type (ICR, C57, KUNMING)? If it is the rat, what is also the best subtype ?

    Shivika Rai · Central Drug Research Institute

    Dr. kamat gave the correct answer.

  • Han Ping Fung added an answer in Data Center:
    Do you think " cloud computing " will replace " data center " for backup data?

    Hello , big companies that has data center are they going to shift from keep a backup of their data in "data center " to upload all backups to the cloud or something like that , please do share your opinion.
    thanks in advance

    Han Ping Fung · Hewlett-Packard

    "Depends ..." is the answer.  But in the context of "Big companies that has DC that consume cloud services (not big Cloud Service Provider)", normally they don't backup all their data into cloud due to many reasons like security, connectivity, compliance, government regulatory requirements etc. (depend on what types of cloud deployments also).  But some big companies do backup some non-critical data into cloud or upload their apps like web or business logic to certain extend to cloud but data remain in more secured DC.

  • Is sugar over consumption the underlying cause of the obesity epidemic?
    The current obesity paradigm is basically behavioural; overeating and under exercising as the cause of obesity. Both true but neither has explanatory power unless people deliberately set out to become obese.

    A single underlying cause is the over consumption of sugars. It fits the descriptive epidemiology: pandemic, both genders, all ages, increasing since the 80's, high prevalence. It fits the biochemistry as causing insulin resistance via glucose consumption stimulates appetite and reduces exercise. It fits the epidemic of Non Alcoholic Fatty liver Disease through fructose. This model supports both individual and public health responses: low sugars diets and low sugars food availability. It also supports recent observational studies and meta-analyses that fats are part of the solution, not part of the problem. Until the paradigm shifts back to the pre-50's diets, we will continue to do the ineffective, calorie restricted diets and increasing exercise, instead of decreasing sugars intake both as individual interventions and public health policy.
    Max Stanley Chartrand · Northcentral University

    All artificial sweeteners are poison to living organisms. No matter how we design our studies to show short timelines, understated measures, wrong measures, or any other self-serving approach to try and convince consumers and regulators that they are safe and harmless, the long term outcomes on humans and short term effects on animals is not a pretty picture. We demonized sugar to the point that consumers are made to feel a moral justification for downing hundrreds of gallons of artificially sweetened drinks annually. And at what cost to individuals and society? 

  • Can we insert market reconfiguration as innovation?

    Innovation, creativity and entrepreneurship are directly related to social and economic development.

    What if reconfiguration is considered as creativity.

    Upananda Witta Arachchilage · Wayamba University of Sri lanka

    The definition of reconfiguration is re-arranging parts of something (Oxford Dictionary).  Then re-arranging market configuration is definitely an innovation according to Schumpeter (1934). Schumpeter's sources of opportunities still  remained valid even after nearly eight decades.

    Upananda

  • What does the term “Research Culture” mean to you?
    When we discussed about Research Culture, I saw this is an interesting topic that researchers have different opinions about it. Please share your opinion with me.
    Is there any dos and don'ts in research? Is the term Research Culture in existence? Is it positive? Does it have any negative facet?
    Taiguara Villela · Universidade Federal do Espírito Santo

    Research culture is a comportamental component. Thus I believe that the interest in the truth and the habit of search are determinants on foundations of a Research culture in general. But I believe there are plural cultures of research and not just one culture of research, because each search method assumes a specific culture for the development of a field of research. The culture of research on Theory of Information on Physics is different compared to culture of research on Theory of Information to Bibliometrics and Archivistics.

  • Noor Ul Haq added an answer in Abiotic Stress:
    How I can get the target genes of transcription factors?
    I have transcription factors and want to know their target genes. Can anyone please give suggestions for how I can do so, and what kind of tools I should use?
    Noor Ul Haq · Shanghai Institutes for Biological Sciences

    @Munusamy Vivekanandan yes that is a good idea.... Thanks so much

  • Debasis Manna asked a question in Akt:
    If compounds decrease the both AKT and pAKT expression level in cancer cell lines, what is the probable mechanistic pathway ?

     Compounds are non toxic but decrease both AKT and pAKT expression level.

  • Jolly Antony added an answer in Green Synthesis:
    What exactly does 'Green Synthesis' mean?

    Not a definition, requires description in terms of solvent usage/ reaction conditions.

    Jolly Antony · Cochin University of Science and Technology

    Synthesis of a substance without badly affecting the environment. Green chemistry aims at carrying out a traditional synthesis procedure or a new procedure following the principles of green chemistry. Use green solvent (water ) instead of organic solvent, minimise waste and hazardous products, utilise waste etc. 

  • Do you support the establishment of the industrial plants by a university?

    A university, with a student population of e.g. more than 25,000 & with academic, administrative, and services staff of e.g. more than 2000, consumes lot of papers (despite the existence of electronic displays & versions) and lot of liquid detergents for its laboratories, cafeterias and water closets. If such a university has qualified staff, it can start two medium-scale batch chemical industries to produce what the university needs of these 2 items (papers & liquid detergents).These 2 industries can be made environmentally-friendly.

    Advantages of these 2 industries are enormous. To start with, the university will save money & will train students industrially on the campus.

    Some industries have gained huge profits from universities, but when it comes to supporting  research in academia or accepting students for training in their practical service courses, these industries show negative attitudes. Isn’t it time for the universities to stand up & industrialize part of their activities?

    Dr. Nizar Matar · An-Najah National University

    The contribution of Prof. Marwan is highly valuable. Academic staff in a university have abilities that are not well-utilized. In large universities, they can produce many things  needed by the staff & the students. A colleague, who graduated from a German university, told me long time ago, that the faculty of agriculture in his university has an industrial dairy products plant that moved from small-scale into large scale production. Its profits covered a high percentage of expenditure of all the university. 

  • Yao Chuang asked a question in Percolation Theory:
    Can you help me to find the best book or article on Monte Carlo techniques for charge transport in disordered organic semiconductors?

    I would like to use Monte Carlo techniques to simulate the charge transport in  disordered organic semiconductors. When  I was learning the reviews (Charge Transport in Disordered Organic Photoconductors a Monte Carlo Simulation Study.physica status solidi (b) 1993, 175 (1), 15-56. and Baranovskii, S. D., Theoretical description of charge transport in disordered organic semiconductors. physica status solidi (b) 2014, 251 (3), 487-525. ), I find the percolation theory was so diffict for me. So please help me.  How to combine the percolation theory with the Monte Carlo  simulation.  Thanks very much.

  • Steve Russell added an answer in Noise:
    Why noise effects more to high frequency components than low freq components?

    In order to combat this?

    Steve Russell · Iowa State University

    Youssef is on the right track.

    The definition for resistor noise is as follows:

    The AVAILABLE NOISE POWER, P, for a resistor is the product

    Available Noise Power = kTB
    Where K = Boltzman's Constant = 1.38 *10-23 Joules/Kelvin
    T = The physical temperature of the resistor
    B = Effective noise bandwidth of the measurement.

    The mean-square noise voltage produced by a resistor is

    Ave(V**2)=4kTBR

    where R is the resistance in ohms.

    I used to design very low noise amplifiers. I could connect a 50 ohm resistor to the amplifier input and measure the output noise power level. If I took my soldering iron and brought it near the resistor, the power meter reading would go up corresponding to the physical temperature of the resistor.

    If you want to be an expert in electrical voltage or power produced by resister thermal noise , it is important to learn the meanings of the terms effective noise bandwidth (it is not the 3dB bandwidth except in very special circumstances) and available power.

  • Morgane Moreau added an answer in NGS Data Analysis:
    Does anybody have any idea about XT:A:M Tag in sam file?
    I got some XT:A:M tag in sam file. XT:A:U means Unique mapping but what does XT:A:M mean?
    Morgane Moreau · James Cook University

    Dear Roop,

    Can I ask which tool you use to filter XT:A:U and MapQ at the same time?

    Thanks a lot

  • Abdallah Samy added an answer in Leishmaniasis:
    Which genomic tests are available for insecticide resistance in phlebotomine sandflies?
    We want to investigate insecticide resistance levels in Phlebotomus sandflies from Syria and would like to pursue the genotypic route if possible because phenotypic work is not feasible in the war zone.
    Abdallah Samy · University of Kansas, and Ain Shams University, Cairo, Egypt

    What do you mean by genomic test?i think if you like to test the mutation that may be caused by the use of specific insecticide, this will be determined based on what type of insecticide you use and what are the target protein you like to test. I would prefer to do cDNA. So, you can detect the possible mutation that may be caused by insecticide over generations. 

  • Does anyone know the mechanism of dehydro-aromatization of cyclohexene by MnO2?

    I want to know the mechanism of MnO2 in the last step of  the attached file.

    Eric B. J. Harris · Australian National University

    Manganese dioxide is a polymorphic, non-stoichiometric (more accurately MnO(2-x)), heterogenous reagent.
    The chemistry takes place on the surface interface. The irregular surface of MnO2 its polymorphic nature and non-stoichiometry results in areas of activated surfaces that can be considered as free radicals. In the simplified scheme below I have represented the reagent as a localised reactive site with two oxygen centred radicals.

    In reality it is a contoured three dimensional surface with varying surface speciation. The exact speciation of the reactive sites on the MnO2 surface is neither easily determinable nor particularly important.

    The reactive surface will in effect abstract the most easily dissociated hydrogen atoms in a most likely non-concerted fashion, however this intermediate is unlikely to be long lived. Most of the organic chemistry and behaviour of MnO2 can be adequately explained and predicted from this knowledge.




    A simplified scheme is attached. 

  • Who can help in application of neural networks (NN) in load flow analysis?

    Supply me by any documents, examples, and MATLAB codes.

    Salah Eldeen Gasim · Sudan University of Science and Technology

    Your points are very helpful dear Mr. Chathura Senanayake,

    I will try that and get back to you.

    Great thanks Sir.

  • Abdallah Samy added an answer in Ebola Virus:
    Do you expect that Ebola virus is environmentally stable?

    The response of Ebola to climate seems constant or changed over time! Could we test this question based on the data for the outbreak. A study published by EcoSurveillance show that there is a correlation between some environmental factors and Ebola spread?

    http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20892

    Abdallah Samy · University of Kansas, and Ain Shams University, Cairo, Egypt

    It is very easy but need some time (J:)

  • Saima Hassan added an answer in Machine Learning:
    If we obtain many results from different models given the same input, is there any technique to select the best result corresponding to that input?

    We trained the same input data using 5 different methods (machine learning models). As a result, some of them output the same or different results and we don't know which  result is the best output.

    Question: is there any scoring function or classification method which allows to select the best result from the obtained outputs?
    e.g., outputs A, A, A, A, B  ==> Best output = A

            outputs A, B, A, A, B ==> Best output = B

            Etc.


    Saima Hassan · Kohat University of Science and Technology

    agree with the comments of @Sebastian Raschka , you can see my paper on this as well."Neural network ensemble: Evaluation of aggregation algorithms in electricity demand forecasting "

    http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6707005&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6707005

  • Hyunwoong Ji asked a question in Websites:
    Is there any journal for data-mining on healthcare?

    Hi, all. I am not sure that it is appropriate to upload this question to this website. Therefore, if you think so, please do not hesitate blame me.

    The following is what I am curious about.

    These days I am interested in applying various of data-mining skills on health-care areas like predicting a visiting-day of a certain patient or find out potential patient so on. However, it is hard to search a journal of which research area covers the aforementioned topics. Most of them which I found ( I mean a journal) covers application of data-mining on various area not just on health-care domain. If you know some journals like what I am trying to find out, I will be waiting for your response.

    Thank you in advance.

  • What is the role of MgCl2 in PCR?

    PCR amplification effects by the MgCl2 concentration. That what happen in an experiments I carried out. I need more advices and recommendation until what concentration the amplification could yield good result in the PCR

    Deepshikha Sharma · Osmania University

    Mg2+ acts as a cofactor for DNA/RNA Polymerase. It facilitates nucleophillic attack by 3ÓH group of primer on alpha phosphate group of the incoming nucleotide which is required for bond formation. It also facilitates removal of the pyrophosphate left. Moreover, Mg2+ stabilizes the transition state acquired during the polymerization reaction. In general,1-4mM MgCl2 is used in PCR reaction mixture (1.5mM for 0.2mM dNTPs). If EDTA is present in the buffer then Mg ion concentration should be increased to compensate for Mg removed from the mixture by chelator. Optimum concentration gives good fidelity whereas higher concentration leads to non-specific amplification.

  • What happens to TEOA in photocatalytic CO2 reduction?
    In some photocatalytic CO2 reduction systems, it is necessary to use a sacrificial electron donor, such as TEOA. Can someone tell me what happens to these electron donors? Is there any way to regenerate them?
    Yurii V Geletii · Emory University

    It becomes oxidized. The regeneration is complex  and requires too much energy 

  • Husein Hadi Abbass asked a question in Noise:
    Why the noise image matrix is fuzzified in ( SHHY) algorithm

    ( SHHY) algorithm The standard Husein , Hind and Yahya method for removable salt and pepper image noise. See the article "A NEW METHOD OF REMOVING SALT AND PEPPER NOISE IMAGE USING MV- ALGEBRA "

  • Jeff Baker added an answer in Dance:
    I am working on folk media for my Phd can any one suggest good books and articles to read?

    By folk media I mean traditional means of communication like music, dance, rituals and oral narratives. Using which I want to understand the social set-up of a community.

    Jeff Baker · Southern Cross University

    Carey, JC 1992  'Communication as Culture, Revised Edition: Essays on Media and Society'

    Connell, J & Gibson, C 2003 'Sound Tracks: Popular Music Identity and Place'

    Young, K 1993 'Bodylore'

    Nicholls, RW  1997 'Folk Media: Indigenous Learning Systems and Instructional Methodology'

    The Folklore Forum journal is good and the Folklore and Ethnomusicology Publications Website