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  • Adam B Shapiro added an answer in Carbonic Anhydrase I:
    Which of PH-sifted assay or esterase assay is the most accurate?

    I am not very familiar with techniques used in experiments when it comes to find Ki of a ligand. For a protein such as carbonic anhydrase, I realized (from litterature review) that the reported Ki for the same molecule will generally vary if the PH-sifted assay is used instead of the esterase assay. Apparently PH-sifted assay usually gives lower values than the other technique. Which of these techniques should be most trusted or is more accurate?

    Thank you!

    Adam B Shapiro

    The value of Ki is sensitive to the conditions, including temperature, pH, ionic strength, the concentrations of various ions, and the type of pH buffer used. Compare the conditions used for the two assays to see if there are any differences that might affect the Ki.

  • Faris Alshubiri added an answer in International Trade:
    Any one can help me to find literature review of cultural effect on international trade?

    I will appreciate if you help for these questions thank you all of you. this will help me very much so thank you agian

    Faris Alshubiri

    Dear Mohamed Abdirahman


    Please find the attached file about your question may be useful for you,

    Best Regards, 

  • Dhruv Bhatia added an answer in IMS:
    How do I run different scenarios in my Open IMS SIPp tool?

    By default I am able to run my ims_reg scenario but not the other scenarios.

    Dhruv Bhatia

    I think I got the answer to this. So all the scenarios file are automatically executed once all the registrations are complete. I configured my manager.xml file to restrict to just 2000 registrations and after that the ims_uac, ims _msgs, ims_dereg all the scenarios are automatically executed

  • Prakash Dharmalingam added an answer in Xenograft Model:
    Reason for necrosis followed by spontaneous regression of tumor in xenograft model?

    Hello to everyone,

    I'm working with HCT116 xenograft model in NCr Nude mice. All of sudden i came across the problem of tumor necrosis followed by spontaneous regression of tumor and sudden weight loss too. Anybody can help me to sort out trouble shooting in this regard?

    Prakash Dharmalingam

    I have observed this phenomenon, necrosis occurs once the tumor reaches the threshold for its growth, the point at which it may not growth further and accompanied by weight loss too. Tumor growth rate depends on various factors, cell type, age of mice, cell number etc., so you should consider harvesting the tumor and proceed further as your experimental plan.

  • Jochen Wilhelm added an answer in Z-Test:
    T-test or Z-test? I have two sets of data each over 100 cases. What is the right tool to test whether there is significant difference between the two?

    The size is over 30, but I am not comparing a sample and a population. Thank you.

    Jochen Wilhelm

    Is the data interval scaled?

    What kind of difference do you mean?

    If your data is interval scaled your aim is to test the expected difference and n>100 per group ... then both tests are ok. The results will be almost identical, the tiny differences won't be of any relevance.

  • Muna Kareem asked a question in pH:
    Why did the pH of the c-SBF dropped to 1 when I prepared 4 liters at once?

    I've prepared 4 liters (at once) of c-SBF (simulated body fluid) according to the method described by Kokubo,,, but when I finished adding all the materials the pH was 1 instead of 7.5!
    I've used to prepare 2 liters each time and multiplying the amount of each component by 2 and it was working good
    Now I multiply it by 4 to prepare 4 liters...so why did that happened?
    and how can I solve the problem???
    The method of preparation is described in the paper below: 

  • Faris Alshubiri added an answer in Grounded Theory:
    Can anybody help me with research articles on community leadership emergence?

    I am doing research on leadership emergence on the community based organization following the grounded theory methodology. For this, I am looking for the research articles (empirical/qualitative) in the field of community leadership emergence.

    I would be grateful if anybody in this network sends me the works done in the field

    Faris Alshubiri

    Dear Gunajn Dallakoti


    Please find the two attached files about your topic may be useful for you,

    Best Regards, 

    + 1 more attachment

  • Mahmoud Omid added an answer in Negative Results:
    Why is there negativity towards publishing negative results?

    Many experimental results never see the light of publication day. For a large number of these, it comes down to the data being “negative”, i.e. the expected and/or wanted effect was not observed. Despite their potential, negative results are repeatedly relegated to the lab books, the drawers and the trash bins. Prof. Dr. Anthony Cerami once said "Many of the biggest discoveries of my career were the results of failure of another research project. ... Failure strikes a negative tone, but it appeared in my personal history that it was an essential experience on the path to important discoveries.".Should researchers publish their negative results?

    Some new journals like "Journal of Negative Results in Biomedicine" or "New Negatives in Plant Science" encouraging researchers to publish their negative results. But as you know, there is a negativity towards negative results. Why negative results not published by journals as freely as positive results? Is it time to publish research “failures”, too?

    + 1 more attachment

    Mahmoud Omid

    From www.anu.edu.au: Science is a human endeavour. And like humans everywhere, those who work in it will do what they are rewarded for. So we need to make sure those reward structures are encouraging good quality research, not the opposite.

  • Natalia Nikolayevna Kabanova added an answer in Plato:
    Please, help.What is English for the name of Plato's primary school - /didacsaleon/?

    Please, help.What is English for the name of Plato's primary school - /didacsaleon/?

    Natalia Nikolayevna Kabanova

    Thank you very much!!!

  • Mahamad Nabab Alam added an answer in Digital Electronics:
    How can all possible 22 digit binary numbers can be generated?

    I am in a situation where all the possible 22 digit binary number are required. Also, the number must be sorted from smallest to largest.

    Kindly, suggest me the fast and the efficient way to get this all the binary numbers.

    I mean to get the list of all the binary strings between

    00 0000 0000 0000 0000 0000 


    11 1111 1111 1111 1111 1111 

    Thanking in advance..

    Mahamad Nabab Alam

    Dear Zbigniew Jaworski Sir,

    The following codes are working good upto 16 bit binary string, but beyond that its  taking extremely long time to generate the string.

    for n=1:2^nbits

    For 22 bit strings, i think its not possible by an ordinary computer to generate it.

  • Sara Salemhesari asked a question in CST:
    Phase difference vs Frequency IN CST ?

    I am designing a four port 90 degree SIW directional coupler in CST. I lneed to see the phase difference between port 2 & 3 that are "coupled port" and "transmitted port".

    I was wondering how can I see this phase difference vs frequency in CST?

  • Alena Nikolskaya added an answer in Cell Culture Techniques:
    Does anyone has an experience of growing SCC-4 cells from ATCC without feeder cells?

    It would be nice to grow them using some coating, conditioned media, etc. instead of feeder layer.

    Alena Nikolskaya

    Thank you very much, Valeh!

  • Stam Nicolis added an answer in Gravitational Field:
    Is the non locality of the gravitational field energy a serious problem for General Relativity (GRT)?



    "Although there is no room for such a thing in the energy–

    momentum tensor T, it is clear that there are situations where a ‘disembodied’

    gravitational energy is actually playing a physical role.

    Imagine  two massive bodies (planets, say). If they are close together (and we can

    suppose that they are instantaneously at rest relative to each other), then

    there will be a (negative) gravitational potential energy contribution which

    makes the total energy, and therefore the total mass, smaller than it would

    be if they are far apart.  Ignoring much tinier energy effects,

    such as distortions of each body’s shape due to the gravitational tidal field

    of the other, we see that the total contributions from the actual energy–

    momentum tensor T will be the same whether the two bodies are close

    together or far apart. Yet, the total mass/energy will differ in the two cases,

    and this difference would be attributed to the energy in the gravitational

    field itself (in fact a negative contribution, that is more sizeable when the

    bodies are close than when they are far apart)." 


    The same problem was also rised by Thirring, Kalman and Feynman in the FGT theory, they inserted the gravitational energy in the tensor equations...

    It is a problem of paramount importance which prevents the General relativity theory from describing any motion in which the hamiltonian is time dependent or rather in case of non isolated systems, or in case of non stationary interactions between different bodies.

    The attempt to model a free falling body in a gravitational field for GRT seems impossible.

    GRT has been tested  only for static or stationary systems where there is not a net exchange of energy (excluding gravitational radiation)

    Don't we need another GRAVITATIONAL THEORY which includes the results give by GRT in order to explain with a better accuracy the simple phenomenon like the free falling of a mass in a gravitational field?

    Stam Nicolis

    While the statement that the asymptotic metric be Minkowski is a sufficient condition for the definition of conserved quantities, it isn't necessary. And even if the asymptotoic metric is time dependent the only conclusion that leads to is, also, well known, namely that there don't exist observer-independent conserved quantities. But that's not a problem and can be consistently described within general relativity.

  • Marion Javal asked a question in Mitochondrial DNA:
    I find different topology when I make an haplotype network using either Popart or TCS. Does anyone know why ?

    I used Popart and TCS to make haplotype networks with mitochondrial DNA. 

    I used the "TCS Network" option on Popart, and both the options "gaps =5th state" and "gaps=missing" on TCS.

    The topologies I found are differents : TCS found 3 more haplotypes than Popart.

    Any explanation?

  • Lidia Oliveira added an answer in Twitter:
    How to perform "frames in perception" content analysis and sampling of face book comments?

    I am looking to perform "frames in perception" analysis of face book comments. I am looking for helpful articles which could guide my research. Are there any identified "frames in perception" in social media specifically face book or twitter for that matter? 

    Secondly, the sampling of comments is another area of concern. As face book posts in those communities which are selected for this study usually have comments exceeding 5000. Is there any guideline regarding appropriate selection of sample?

    Thirdly, to perform aforementioned two tasks, Is there a better software?

    Lidia Oliveira

    Dear Salman Yousaf

    The Software NVivo 10 has analysis functions of social networks, namely Facebook.

    I suggest you see here: http://help-nv10.qsrinternational.com/desktop/concepts/approaches_to_analyzing_facebook_data.htm

    Good work!


  • Ian Kennedy added an answer in Social Pedagogy:
    How do teachers deal with mismatch between belief and practice?

    I'm interested in how teachers might articulate a particular 'belief ' about teaching and learning - yet their practice seems to be at odds with this 'belief' ( observed practice) . My interest lies within the teaching of science and the assessment of inquiry skills. 

    Ian Kennedy

    For your literature review, start with this link:

  • Tori Kohler asked a question in Writing:
    Suggestions on enzymes involved in oxidation-suggestions for assays?

    I am writing a research proposal that is generally about identifying certain intracellular bacterial enzymes that are responsible for oxidation of a polymer during beta-oxidation. Would anyone recommend a specific assay for identification of intracellular oxidases? I really would appreciate some help with this. Thanks.

  • Vatsala Sharma asked a question in Probability:
    What is the difference between bayes test and Neyman-Pearson test in terms of sensing in cognitive radio networks?

    In Bayes approach individual detection threshold are determined for evaluating probability of detection and probability of false alarm while in NP probability of false alarm is fixed. Please explain?

  • Takeshi Matsuishi added an answer in ANOVA:
    Methodological question: how to present data IQ and Vineland data?

    in a retrospective study about ASD I have IQ data for N=133, Vineland data for N=40 and for N=150 both Vineland and IQ. I want to examine the relationship between functioning and a nominal variable with 3 values using ANOVA. My question is how to use the functioning data? Can I use an average of IQ and Vineland?

    Takeshi Matsuishi

    Dear Shahar

    I am sorry. I did not have time.

    Diagnosing as ID, both ID test and behaviour ability assessment are necessary, if ASD are complicated.

    But in these case, considering the particularities of IQ structure and behaviour abilities because of these factors,you must use take a flexible attitude to the Vinelan scale and measures adaptive behaviour.

  • Tori Kohler asked a question in Extracellular Enzymes:
    Suggestions on assays to run for identification of extracellular secreted proteins?

    Hello-I am currently writing a research proposal regarding degradation of certain polymers by bacteria but I am not sure what kinds of assays I should be running to identify particular secreted extracellular enzymes that are involved in breakdown of the polymer. Any suggestions would really be appreciated. 

  • Faris Alshubiri added an answer in Banking and Finance:
    I need literature on Bank's risk taking behavior if you can advice my some good articles or literature surveys on the topic?

    It will be very helpful if you can share literature surveys on the bank risk taking behavior i.e. why do bank takes risk? or any article you consider important for the topic. Thank you!

    Faris Alshubiri

    Dear Yasir Riaz 


    Please , find the attached file about risk taking related for your topic 

    Best Regards, 

  • Shahid Bashir added an answer in Knowledge Transfer:
    Students perspective: mid-term exam = copy - paste; final exam = cut - paste; where is the knowledge transfer?

    Exam-oriented approach is a major threat to knowledge transfer and critical thinking?  It  stifles  students' imagination, creativity, and sense of self.What do you think?

    Shahid Bashir

    Thank you for your contribution ,Bruce .

  • Kantheti Sirisha added an answer in Dentin:
    Does anyone know about a recent review paper on dentine from different sources (human, bovine, ivory etc)?

    I have been looking for a review paper that had compared different dentine models, its similarities,differences, and characterization of these models. Please share the link if you know of such article.

    Kantheti Sirisha

    Hope this could be relevant and useful.




  • Ilya Tsyrlov added an answer in Viral Load:
    Can anyone suggest me the best HBV viral Load Positive control for Real time along with the full details of company providing this??

    Hello Frnds,

    I want to get HBV viral load positive control for real time PCR so that I can easily Plot the LJ chart of the sample results. so please suggest me which is the best?...

    Ilya Tsyrlov

    Hi  Shaifali Gupta,

    You might find all information you requested in the following paper of T. Welzel et al. “Real-Time PCR Assay for Detection and Quantification of Hepatitis B Virus Genotypes A to G”, published in J Clin Microbiol, v.44(9); 2006 PMC1594718

    ABSTRACT: The detection and quantification of hepatitis B virus (HBV) DNA play an important role in diagnosing and monitoring HBV infection as well as assessing therapeutic response. The great variability among HBV genotypes and the enormous range of clinical HBV DNA levels present challenges for PCR-based amplification techniques. In this study, we describe the development, evaluation, and validation of a novel real-time PCR assay designed to provide accurate quantification of DNA from all eight HBV genotypes in patient plasma specimens. A computer algorithm was used to design degenerate real-time PCR primers and probes based upon a large number (n = 340) of full-length genomic sequences including HBV genotypes A to H from Europe, Africa, Asia, and North and South America. Genotype performance was tested and confirmed using 59 genotype A to G specimens from two commercially available worldwide genotype panels. This assay has a dynamic range of at least 8 log10 without the need for specimen dilution, good clinical intra- and interassay precision, and excellent correlation with the Bayer Diagnostics VERSANT HBV DNA 3.0 (branched DNA) assay (r = 0.93). Probit analysis determined the 95% detection level was 56 IU/ml, corresponding to 11 copies per PCR well. The high sensitivity, wide linear range, good reproducibility, and genotype inclusivity, combined with a small sample volume requirement and low cost, make this novel quantitative HBV real-time PCR assay particularly well suited for application to large clinical and epidemiological studies.

    Best wishes,

    Ilya Tsyrlov

  • Stefano Quattrini added an answer in Doppler:
    Is the Doppler Radar or loop of radiation fully explained with the Lorentz Transformations?

    A loop of radiation is a radiation starting from the RF of an emitter, bouncing on another relative moving object (RF1) and returning to the same RF of the emitter.

    Such radiation loop is the same as the implementation of the Doppler Radar.

    Only using the twice the forward LT transformation is possible to account for the frequency ratio of the Doppler Radar...

    The loop of radiation does obviously not belong to a Transformation Group.

    Some doubts raise about the applicability of LT in case of systems exchanging radiation.

    • Source
      [Show description] [Hide description]
      DESCRIPTION: A radiation loop is a closed loop of radiation between reciprocally moving bodies, it comes out as simple application of the Relativistic Doppler Effect (RDE) which was derived from the Lorentz transformations (LT). The forward LT have to be applied twice to justify the loop frequency ratio so that the radiation loop does not belong to a transformation group. The RDE loop can deal with the case of non-accelerated Reference Frames (RF) exchanging radiation.
    Stefano Quattrini

    Dear Erkki,

    I studied a lot the RDE and LT by now. The problem of the closed path of radiation is just a dobule application of the RDE or a double application of the Lorentz transformations. There is nothing particularly strange in that application, it would be invertible by applying L-2.

    The RDE is just what occurs when I assume that the radiation Exchange occurs between inertial reference frames. That the IRF is an ideal (never occuring) condition is true, it can be a very good approximation for a Physical system though.  In the case where the radiation recoil is large, then the system lose its inertiality at least during the absorption or emission of radiation.

    It is the problem of the infinite massive wall, such system absorbs the momentum and reflects the ball. If the scattering is inelastic, the momentum is transmitted to the wall but its effects cannot be detected. If the wall is not so massive the effect can be detected in a variation the status of the wall. This basically alters the inertiality of the object like in the case of the radiation.

  • Anthony Bressi added an answer in Palladium:
    Please advise us on how to deoxygenate with suitable reagents?

    We are using palladium carbon for reduction of alcohol. but rate of reaction is very slow and some time total reaction not completed. 

    Anthony Bressi

    What type of alcohol are you attempting to reduce?

  • Sachin A. More added an answer in RNA Extraction:
    Anyone familiar with RNA extraction from fish?

    hello i did extraction of RNA from fish using geneall kit and i used the TAE gel for rapid confirmation of RNA integrity.

    as I can see in the picture, i have the two bands of 26S and 18S but there is other bands in upper part.

    what is the possible cause of that? what is the nature of these bands?

    Sachin A. More


              I feel it is not the problem of degradation, if it is problem of degradation then 26s and 18s bands would not be intact. Try to check integrity of your RNA on gel once again you will get to know if it is getting deteriorated. I guess it may due to secondary structures in RNA that may affect the mobility of RNA on gel but not very sure. Another point is those higher kb bands concentration is less may due to the lesser concentration of those profiles in your RNA sample. But it's surely not gDNA. 

  • Zahra Esmaeeli asked a question in Surface Modification:
    Whether the intensity of peaks in FTIR indicates interaction between two materials or not?

    i conducted surface modification on a protein by another one.in order to investigate interaction between these proteins FTIR spectra was taken. results exhibit no shifting in peak positions and reveals the intensity of amide peaks became higher.i am wondering is it possible to conclude that increasing the intensity of peaks represent any interaction between two proteins?

  • Azu Azaath asked a question in Particle Swarm Optimization:
    Can any one help me to solve my problem in pso my objective function is to minimize the surface roughness and tool wear ?

    i took all experiment data and solved by using traditional techniques in optimization. but i want to solve my problem in particle swarm optimization