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  • Srikanta Kundu added an answer in VAR:
    Can anyone help with a lag length problem in Johansen-Cointegrated test?

    I am doing causality test. The selected lag length is 4 based on lag criteria. If I take lag 4 in Johansen-Cointegrated test, it becomes insignificant. But if i take lag 1 or 2, it becomes significant. Can i take lag 1 or 2 in place of lag 4 and run VEC model in stead of Unrestricted VAR model.

    Srikanta Kundu

    You should select your optimum lag by minimizing SIC/AIC/HQ criteria. You can also select your model by likelihood ratio test such that incorporation of one additional lag does not significantly increase the likelihood of your model. 

  • Ira L Cohen added an answer in Regression Analysis:
    How can I calculate or estimate the interactions of several variables to predict an outcome?

    Sometimes there are lots of variables which are related to predict an outcome and can be considered confounders of each other. So, regression analysis usually help adjust for these variables. 

    The situation will be complicated if 2 or 3 outcomes are related with other and happen together frequently. In this case, how can we accurately and scientifically estimate the interaction of independent and dependent variables?

    How can we find that " which independent variable is the strongest predictor of each outcome?

    thanks for your comments in advance

    Ira L Cohen

    Do a multiple regression analysis for each dv, correcting for multiple comparisons across dvs. You can add relevant interactions through dummy coding. Check beta weights for importance of predictors but make sure assumptions of the model are met, eg, multicollinearity not an issue. 

  • Fabien Schultz asked a question in Oxylipins:
    Any suggestion on how to do methylation as derivatization method for GC-MS analysis without highly toxic diazomethane?

    I have to perform methylation of free fatty acids / PUFAs for GC-MS analysis. I also want to analyze oxylipins (lipids with hydroxy groups) where I perform silylation with BSFTA directly after methylation with diazomethane.

    So right now, I am either using trimethyldiazomethane or diazald to produce diazomethane that is used for methylation of carboxylic groups. It is very toxic and carcinogenic.

    So I was thinking of other ways for methylation in order to make the FA volantile. I already tried TMSH and lipase-catalyzed methyl esterification with non-satisfying results. Do you have any suggestions?

  • Manas Chakraborty asked a question in Cancer Biology:
    Hello.I am Manas Chakraborty..I am in need of research proposal on pharmacology.Please send me some sample of such proposals?

    Please try to send me proposals basically related with cancer biology or neuropharmacology research.

  • Anxin Wang asked a question in Stock Solution:
    How to dissolve Lomerizine HCl for animal experiment?

    I want to test Lomerizine HCl in mice. But its solubility is not very good in water. If we want to use oral administration (30 mg/kg), the administration volumes is very high according to the solubility(4 mg/mL in DMSO and <1 mg/mL in water). So, how to dissolve this drug? How to prepare the stock solution and working solution?

  • Carlos R. Gonzalez-Gonzalez added an answer in Condensed Matter Physics:
    Is X-Ray Diffraction of an electrical conductor possible ?

    I recently came across the concept of skin-depth of an conductor in Electromagentism , which says that after the skin depth distance below the surface , the eloectromagnetic waves eventually die out( exponentially it becomes 1/e after this distance).

    We  explain X-Ray Bragg defraction  using planes of atoms and find out a condition of maximum diffraction of the light from two planes.

    So how do I explain a Xray diffraction of  a conductor, which as per Maxwell's equations should not allow penetration of electric field/light ? 

    Carlos R. Gonzalez-Gonzalez

    Hrushikesh Sable has posted a very interesting question. If we examine the two skin effects separately (the confinement of high frequency electric current near the surface of conductors; and the confinement of X-Ray Diffraction to the near surface layers, specially in high absorbent materials) no correlation is to be expected. Only is valid the question about if the skin characterized by XRD is the same as the skin in which take place the electric current.  But, what could be expected if an XRD pattern is obtained when a high frequency current IS FLOWING-THROW a piece of metal? It should be an interesting experiment, because the XRD pattern is created by the scattering of electrons, and the free electrons in this case are no more moving chaotically, but in an ordered (collective) way.  I have not more than a few doubts that very amazing things may arise, perhaps a new way to characterize surfaces.

  • Ira L Cohen 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?

    Ira L Cohen

    Agree with above but I  suspect you will find the two highly correlated assuming no range restriction.  Plot them.

  • Ahmed Talib asked a question in Image Classification:
    What are the new trends for medical image classification, Are there any standard medical dataset?

    what are the new trends for medical image classification. In other words, what are the current works on medical images ?

    Are there any standard medical dataset?

    Additionally, what are good feature selection methods for such type of datasets?

    Thank you.

  • Joanna Żebrowska added an answer in SDS-PAGE:
    Why at not getting smaller (below 30 kD) bands are not resolving in 12.5% separating gel ?

    SDS-PAGE using soya bean radicals as a sample.

    Joanna Żebrowska

    Yes, I agree with Mauricio Hernandez. You should try to make 12% gel tris-tricine that 30 kDa band will in the start of the gel and band below 30 kDa will be well separated.  You remeber that the top gel (5%) should be wider than normal tris glycine. you can try also prepare tris tricine gel with no standard bis acrylamide but just more percentage bis akrylamide.

  • Reda Koramy added an answer in GEANT4:
    How do I estimate radiation risk from organ doses?

    Dear all

    We did Monte Carlo-simulations of a fluoroscopy experiment with Geant4 by irradiating XCAT voxel phantoms. The simulation returns a dose per voxel. Together with the organ information we get organ doses etc.

    In a first analysis we calculated the effective dose using  ICRP 103 tissue weighting factors. This seems incorrect, since ICRP 103 says: ".. nor should it be used for detailed specific retrospective investigations of individual
    exposure and risk".

    We now produce dose-volume-histograms to see the dose distribution in each organ and the maximum dose in a voxel.

    What do you consider a good value to estimate radiation risk from MC results and to compare it to legal requirements?

    Thanks for your input,


    Reda Koramy
    What is the active role of the external magnetic field affected on electrical corona discharge in hollow cathode tubes?
  • Mokonen Merga Iticha asked a question in Reference Materials:
    Requesting reference material for thesis, or title

     "I am Mokonen Merga Iticha; currently i am one of the student of Masters of science by a program of "Climate change and Development" In Arba Minch University, Ethiopia. And now, only two month is left to wind up the course of class, which means after two months on ward i goes to conduct a thesis. So, i want to conduct my thesis on a thematic area of climate change effect on hydrological Extremes in a River Basin, Ethiopia". Taking in to consideration of this thematic area, i am happy if you provide reference materials. I hop you will do. Thanks for your response!." or If you have a title which is funded i am eager to do with you. Thank for cooperation!

  • Ahmed El-Zeiny added an answer in Water Quality Analysis:
    What are the research parameters of river water quality analysis?

    Generally we use WQA for drinking water using WHO standard or national water quality indexes. Some countries also following river water quality analysis as per plankton, algae, benthos and invertebrates (aquatic flora and fauna. Fish species and their feeding ground would be the another parameter we can assume for WQA. Besides these what are the scientific standard as we can use the best method for river water quality analysis?

    Ahmed El-Zeiny

    To assess water quality in River Nile, you have to consider physical, chemical and biogical characteristics. Examples of important parameters; pH, turbidity, BOD, COD, ammonia, feccal coliform and heavy metals. 

  • Gertrudis Rojas added an answer in ELISA:
    Does anyone know if, in ELISA sandwich assays, human plasma used as sample may bind non-specifically blocking buffer?

    Here is how I developed my ELISA sandwich: capture antibody (Rabbit polyclonal Anti-Human) in coating buffer (pH 9.6), blocking buffer (BSA 1% in PBS), sample (human plasma), primary Ab (Mouse Anti-Human), detection Ab conjugated to HRP. I obtained a good signal:noise ratio. Then I tried the same assay but without capturing Ab and surprisingly I obtained the same signal. I was expecting a lower signal, since by blocking the well plasma should not bind to it. What happened?

    Gertrudis Rojas

    The IgG concentration in undiluted plasma samples is huge, totally far from the useful ELISA range. Im  sure that a high background is almost unavoidable. Besides background, its not posible to measure IgG concentrations in a proper way using undiluted plasma (they are in a large excess)  

  • Napoleon Ono Imaah added an answer in Ethics:
    Could people comment on the moral imperatives in caring for involuntary psychiatric patients?

    I am working with South Australian law but am interested in international law.  Who are the carers?.  What support do they receive?   Have used deontological and utilitarian ethics, where does ethic of care come in?  How can the needs of the patient be balanced with the needs of carers, families and communities?  Stereotyping of the patients and their needs is a  problem. 

    Napoleon Ono Imaah

    Could people comment on the moral imperatives in caring for involuntary psychiatric patients? 

    People could comment on the moral imperatives in caring for involuntary psychiatric patients; If they have the necessary opportunity and knowledge to do so. 

    Who are the carers?. Carers could be caring family members,  friends and donor organizations such as churches, NGO, and governments that support  psychiatric patients for free. There are career carers who care for psychiatric patients for a fee and for a living. Family and donor organizations are self-supporting; Career carers depend on family and donor organizations for funds to support psychiatric patients.

    A combination of Deontological ethics in terms of right action and the nature of duty by carers donors and governments; with elements of nonmoral good, such as giving health to the involuntary psychiatric patients in Utilitarian ethics have more hope of help to involuntary psychiatric patients. 

    The needs of the patient cannot  be balanced with the needs of carers; since normal careers need to manage involuntary psychiatric patients to normal health. With the active support of families, friends, donors governments and sympathetic, empathetic communities. Each involuntary psychiatric patient should be handled with appropriate individual care by careers.  

    Stereotyping of the patients and their needs is a  problem. 

  • Marco Marchesi asked a question in Deep Learning:
    EEG-based emotion recognition by Deep Learning?

    I have trained and classified EEG data with some machine learning methods in the past and now that I'm going to work with a new EEG headset I would like to explore Deep Learning (I have some demo experience in Computer Vision with it). I read a couple of papers, I'm curious about any implementations, particularly I'm interested to run tests with Theano or Google's TensorFlow.

  • Ivan Petković added an answer in BCl2:
    I found that rituximab does not overcome negative prognostic impact of bcl2+. Does anyone have the same findings?

    I found that rituximab does not overcome negative prognostic impact of bcl2+. Does anyone have the same findings?

    Ivan Petković

    Dear colleague, I absolutelly agree with your opinion. However, in our study we did not test MYC ICH expression, so the conclusion that bcl2 alone has an adverse effect in rituximab era is under the question. Thank you for your opinion.

  • Lucio Munoz added an answer in Income Inequality:
    How (does) income inequality increase with economic growth?

    Should emerging India be at ease with inequality?

    Lucio Munoz

    My apologies to all, it should have said



    a) The invisible hand has not been a friend of social wellbeing; nothing is said then about environmental wellbeing;

    b) The trickle down effect has not been a friend of social wellbeing

    d) poverty, inequality, both social and environmental have been increasing as economic growth has been increasing...:



  • Sian Cooper added an answer in Translation Studies:
    Does anyone know any theory about the concept of 'lost in translation'?

    aspects of source text

    Sian Cooper

    Hi, Abbas. I think the answer is, there is no single all-encompassing theory of translation (loss or otherwise).

    If you are not familiar with it, you may be interested in 'A Methodology for Translation', Jean-Paul Vinay and Jean Darbelnet. An English version can be found in Lawrence Venuti's Translation Studies Reader, pp 84-93 in the 2000 edition.

  • Mario Radovan added an answer in Ethical Analysis:
    Which influential ethical theorists claim that inter-subjective attunement (sharing affective states with others) is necessary for morality/ethics?

    I'm looking for influential thinkers who argue that intersubjectivity is necessary for being moral and/or living a good life. Ideally I want to find examples of well-known analytic, continental, and feminist thinkers who hold this view. Thanks so much!

    Mario Radovan

    Since Hume is the most mentioned name in this discourse, let me put forward a paragraph from a text on which I currently work ("On people and machines").

    We call ourselves rational beings and we are proud of our reason that allowed us to become the masters of the world. Reason is the essential feature of human beings, and a life led by reason is the best life that a human being can live, says Aristotle. However, David Hume points at the other side of the story about life and reason; he says: "Reason is, and ought to be, the slave of the passions, and can never pretend to any other office than to serve and obey them" (in Barash, 67). Many have been perplexed with such a claim, but Hume is right. People have always been led by their emotions and passions. Reason by itself has no motivations and knows no aims, so that it must be led by emotions that move people, and shape their aims and behaviour. Reason is the engine, but emotions, anxieties and yearnings, hold the wheel and decide where this engine carries us.

  • Marie Christine Baqué-Juston added an answer in Pulmonary Embolism:
    What is the most reliable marker in the differential diagnosis of pulmonary embolism and community-acquired pneumonia?

    Because of similar clinical manifestations and laboratory findings, differential diagnosis of pulmonary embolism and community-acquired pneumonia (CAP) is generally difficult. 

    Marie Christine Baqué-Juston

    On CT scan, both infarctus and infection can present as sub-pleural triangular consolidation areas, but there is sometimes a very interesting sign allowing diagnosis orientation: the bronchus entering the consolidated area can have a thickened wall, which is in favor of infection (only true if the remainder of the bronchi in the same lobe have thin walls)

  • Andrzej Radomski added an answer in Ethanol:
    Sodium ethoxide solution is turned turbid white. Is it normal?

    We would like to use sodium ethoxide solution for etching EPON and LR-white EM sections. Today I started making the saturated sodium ethoxide solution. I put 13 g NaOH in 60 ml 96% EtOH. Actually I have no idea of the saturating concentration of NaOH in ethanol.

    After a few hours mixing the solution is turbid white. Is this normal?

    Andrzej Radomski

    Sodium ethoxide cannot be prepared in this way. You should to use anhydrous ethanol (azeotropic distillation with benzene will be sufficient) and weighed amount of pure sodium (metallic!). The reaction leads to sodium ethoxide and hydrogen. In the presence of water ethoxide turns into ethanol and NaOH, so you have to protect an apparatus against moisture using tube with CaCl2, for example.

    Good luck!

  • Job Nda Nmadu added an answer in Regression Modeling:
    What is the most appropriate regression model for a response variable that has non-binary values between 0 and 1?

    What is the most appropriate regression model for a response variable that has non-binary values between 0 and 1? Example of a paper shall be appreciated. 

    Job Nda Nmadu

    Thanks Jochem. I tried my best to do it but..... Below is the code I developed but my problem is that the data is not read. I have 37 variables, can R handle that much? The data file is here attached in case it is needed. I have to disturb you, thanks in advance. 

    data("datatable1", header = TRUE, sep = ",", row.names = 1, package = "betareg")
    ## regression with phi as full model parameter
    gy1 <- betareg(Y~X1+X2+X3+X4+X5+X6+X7+X8+X9+X10+X11+X12+X13+X14+X15+X16+X17+X18+X19+X20+X21+X22+X23+X24+X25+X26+X27+X28+X29+X30+X31+X32+X33+X34+X35+X36+X37, data = datatable1)
    ## regression with phi as nuisance parameter
    gy2 <- betareg(Y~X1+X2+X3+X4+X5+X6+X7+X8+X9+X10+X11+X12+X13+X14+X15+X16+X17+X18+X19+X20+X21+X22+X23+X24+X25+X26+X27+X28+X29+X30+X31+X32+X33+X34+X35+X36+X37, data = datatable1, phi = FALSE)
    ## compare reported output

  • Arafat Ahmed Alkhasha asked a question in Column:
    I can to measure in lab variety soil column to simulation pattern instead of field?

    simulation water papern

  • Ulf Nobbmann added an answer in Particle Size:
    Why does the particle size differ in TEM and DLS measurements?

    I got smaller particle size in TEM (Transmission Electron Microscope) images as compared to DLS (Differential Light Scattering) measurements of my organic sample in THF/water mixture(60% water).

    Ulf Nobbmann

    DLS is an intensity based technique, and this puts higher emphasis on the larger particle sizes. It can be transformed to a number based distribution provided the data quality is sufficient.

    TEM is a number based technique, and will thus show stronger emphasis of the smallest components in the size distribution.

    + 1 more attachment

  • Raid Amin added an answer in Multiple Regression Analysis:
    How do I estimate variance inflation factor VIF theoretically?

    VIF is used to estimate the proportion of variance inflated when predictors are correlated in multiple regression analysis. How do I estimate variance inflation factor VIF theoretically?

    Raid Amin

    The VIF of variable (i) can be found as the reciprocal of (1-R_squared(i)), where R_squared(i) is the coefficient of determination for a model in which X(i) is predicted from the remaining X's.

  • Niraj Kumar Jha asked a question in Abaqus:
    What is the most efficent way to postprocess UEL in Abaqus ?

    Hello Abaqus user,

    As you all aware the visualization of results associated with user elements is not supported by abaqus viewer. I tried to follow the guidelines provided in Abaqus manual to access the results file but no success so far.

    Method -1

    I used fortran interface (attached -source : http://forum.cadec-online.com) to read the results from the .fil-file with ABQmain subroutine.

    abaqus make job=filToBin.f

    This provides me filToBin.o file with the Note: declarations in dependent base » cow_Btree < odb_String , odb_Instance > " could not be found


    Other tricky way which i figured out is  to superimpose another element on the UEL element. which runs on UMAT.   UMAT communicates with UEL via  COMMOM statement  and solution dependent variables (SDV).

    I am more interested to visualize my element using Method-1. Is there any detail explanation to do so ?  can somebody guide me please?

  • Haikai Tane added an answer in Social Theory:
    What stories of how complex adaptive systems "work" have you encountered?

    I have identified some 50 CAS concepts commonly used by authors in the paper.  They range from those derived thru chaos theory and agent-based modeling, to self-organization of agents as they interact and co-adapt, to emergence, etc. I have created one brief story that weaves together clusters of these concepts and then another brief story that weaves together the clusters.

    How important is it to have a coherent story as one applies the concepts to new areas of inquiry?  Is a universal story across domains necessary?  What is it?

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The study surveys 25 popular secondary sources (1992-2014) on complexity theory and complex adaptive systems (CAS) to develop a comprehensive framework of CAS attributes used when authors reference CAS theory. The attributes are analyzed using network analysis algorithms to determine if there are related clusters of concepts. A two level story of theoretical relationships is developed between the attributes within the clusters and between the clusters to augment the CAS Framework. The complete CAS Framework is used to map CAS theory representations from the sources so that comparisons and evaluations of focus and thoroughness can be easily made. The result is a tool that can be used to assess any representation of CAS theory in any context, but especially in the social sciences with human agents.
    Haikai Tane

    Working as an independent professional researcher requires language that can be understood by partnering agencies ~ they tend to react badly to academic jargon like complex adaptive systems modelling and usually demand plain English!!. Over the past 40 years working in complex open system science fields, I have tried many terms and phrases... the one that seems to work best is Eco3Sustainability integrating ecography/ecology/economy in that strict order ~ ie spatial object first, modelling processes second, assessing performance third... there are feedback loops for each stage...the method is used in transdisciplinary heuristic learning by doing R&D  ie participatory watershed projects ... or participatory metro planning projects...

  • Upinder Dhar added an answer in Qualitative Data Analysis:
    Which are different qualitative data analysis techniques ?

    My research is focusing on Qualitative and Quantitative Data collection. I would like to know more about different Qualitative Data Analysis Techniques. How do we go-ahead about Qualitative Data Analysis?

    Upinder Dhar

    One of the most popular ones is "Content Analysis".

  • Bartosz W. Schramm added an answer in Bioinformatic Software:
    Is there an open source automated image segmentation tool for histological cross-sections?
    I am looking for an automated method of image analysis that would aid us in a morphological analysis of histological cross-sections of Beetle tissues. The most promising approach that I managed to find was an AdaBoost and GVF Snake algorithm, but I would need some help with getting through the mathematical formulas to a software. Any advice?
    Bartosz W. Schramm

    It's been almost 2 years since I faced the problem and to date I was able to solve some with ImageJ and Matlab but I will most definitely check it out. Thanks for the heads-up John. I highly appreciate it.

  • Aran Kagen asked a question in Health Psychology:
    Where should I publish my Undergrad Honor's Thesis in health psychology?

    The title of my thesis is "The Influence of Personality and Context on Risky Sexual Behavior among Young Adults." Is it taboo to be published by my institution's honor's journal? I would like to be a competitive applicant to graduate school, so a reputable journal is a must! What are some good resources to find a suitable journal?

    Here is the link to the full thesis: http://scholar.colorado.edu/honr_theses/774