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  • Mohammed Al Marjani added an answer in Colistin:
    Any idea regarding colistin resistance in Moraxella spp.?

    Also, how to study virulence factor in the bacterium?...

    Mohammed Al Marjani · Al-Mustansiriya University

    Dear Sayan

    Most strains of Morexella are colistin-sensitive; some strains are colistin-resistant.

  • Simone Orcioni added an answer in Circuits:
    Some questions on this circuit representing a Colpitts oscillator with balanced output.?

    Referring to Fig 2 on the paper, I-m wondering why the outputs of the circuit should be measured as shown in figure, and not as shown in my picture.

    Thank you all for having attenction.

    Simone Orcioni · Università Politecnica delle Marche

    To me your paint version seems quite identical to the original.

  • Paolo Mocellin added an answer in Comsol:
    How can I deal with the errror "Undefined value found in the stiffness matrix" in COMSOL Multiphysics?

    Hello, everyone. I'm trying to simulate the single dielectric barrier discharge with the Capacitively Coupled Plasma interface and the Time-dependent solver in COMSOL v4.4. And when I choose Finite Volume Formulation, I come across the error as shown in the attached picture directly after the start, whereas if I use Finite Element Formulation instead, the computation can be done successfully (except that the results seem to be wrong...).

    When Finite Volume Formulation is chosen, I can get the initial value of every variables by right-clicking the study node and clicking the "get initial value".

    My model is a 2D model. The error variable comp1.En is Electron enenrgy density.

    Thank you in advance!

    Paolo Mocellin · University of Padova

    Hi, Shahram.

    You usually obtain this kind of messages when the mesh is not build in an optimal way. One solution may be to refine the mesh, especially near critical locations. 

    First of all, try with a coarser mesh. Then refine it.

  • Paresh Poriya asked a question in India:
    Can anybody help me to identify this species?

    This species is found in the intertidal zones of Gujarat coastline of India. 

  • What are response surface methodology (RSM) with multi-responses?

    I usually see RSM-based papers with only one response. However, there are few reports on using RSM with multi-responses. I want to know if there are any difficulties or drawbacks relating to this procedure.

    Sara Asgari · Tarbiat Modares University

    Dear Deepak Unune,

    Thank you for your answer.

    I downloaded the paper and will study it carefully.

    All the best


  • Remi Cornwall added an answer in Causality:
    Is a concept of causality required in science?

    John D. Norton characterized "Causation as Folk Science",

    (see http://quod.lib.umich.edu/p/phimp/3521354.0003.004/1).

    Would you say that causality is a well-defined concept that is

    essentially required in science?

  • Ginés Viscor added an answer in Glycolysis:
    How can I increase ATP levels in mice?

    Hello everybody, I wonder if it is possible to increase ATP levels in mice just giving them water with Glucose in order to push glycolysis. I am working with a liver KO model where OXPHOS seems to be compromised and I would like to test if the morphological changes I can see at cellular level are due to an energy defect. As changing the diet of the animals would take longer, I wonder if it is possible to supply those animals water with some concentration of Glucose in order to push Glycolysis and somehow restore ATP levels. Thanks 

    Ginés Viscor · University of Barcelona

    I assumed your experimental model is exercising mice. Are you asking for a prolonged effort capacity? As explained above by several contributors, at rest, ATP intracellular levels are so tightly regulated that it is unlikely to be changed in a way that can be effectively measured. However, changes in ATP, ADP an Pi levels and proportions have been measured by RMN in human skeletal muscle during muscle contraction.

  • Purva Kansal asked a question in Variability:
    Help with syntax of conjoint analysis in spss ?

    I am trying to work with Conjoint analysis and have copied following code into syntax.

    CONJOINT PLAN='d:\SPSS\samples\english\carpet_prefs.sav'

    however it keeps giving following error 

    Text: PREF1 Command: CONJOINT
    An undefined variable name, or a scratch or system variable was specified in a variable list which accepts only standard variables. Check spelling and verify the existence of this variable.
    This command not executed.

    Unrecognized text appears where end of subcommand (slash) was expected.
    SUBJECT SUBCOMMAND -- Subject variable is not on data file.
    An undefined variable name, or a scratch or system variable was specified in a variable list which accepts only standard variables. Check spelling and verify the existence of this variable.
    An undefined variable name, or a scratch or system variable was specified in a variable list which accepts only standard variables. Check spelling and verify the existence of this variable.

     Can anyone tell me what am I doing wrong? These are all sample files of spss. 

  • Ann Lee asked a question in One-way ANOVA:
    Is there an article with a table containing One-way ANOVA results for 2 separate groups?

    Hello all, 

    I am looking for articles with One-way ANOVA result table, 

    specifically for 2 group comparisons. I want to see the example.

    Thank you. 

  • Tausif Alam added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Tausif Alam · University of Wisconsin–Madison

    "How would anyone who is not trained as a neurologist, based on the latest methods and experimental lab tools, have anything useful to say about how the brain works - in any capacity?"

    And yet, here you are!  

  • Eva Hamilton added an answer in Medicine:
    Are we really drifting towards pre-antibiotic era in view of fast developing antibiotic resistance in pathogens against the current antibiotics?
    Antibiotic resistance among common pathogens is becoming quite frequent these days. Such infections have begun to pose a serious threat to human health. I would like to know the current situation with respect to our preparation to deal with such serious issues of human health.
    Eva Hamilton · Bournemouth University


  • Suhasini Joshi added an answer in Biomarkers:
    Whats the most common biomarker to diagnose breast cancer ?

    Can somebody tell me the most common biomarker to diagnose breast cancer ?

    Suhasini Joshi · University of Nebraska Medical Center

    Hi Manar!!

    Presently, there is no biomarker available for the early diagnosis of breast cancer. However, most common tissue based biomarkers are estrogen, progesterone and EGFR receptors. Analysis of these biomarkers tells the type of treatment which can be used to treatment patients. Besides these biomarkers, CEA, CA15-3 and CA 27.29 cancer antigens are also used. Levels of urokinase plasminogen activators are also used but to know the prognosis in lymph node-negative patient

  • Which paradigm(s) is(are) the most suitable for assessing the economy-environment relationship?

    Given the existence of different schools of thought within social science-at times complementary and at times contradictory-the debate over the way in which this relationship should be conceptualized and analyzed is a hotly contested one.

    Nathan Weatherdon · Nathan Translates

    "Do tell us, José, why 1998 was a "bad" choice. "
    - If you're talking about trends, picking outlier data as a point of comparison will easily lead to misplaced conclusions. Some statistical methods even eliminate outlier data altogether. Climate fluctuates, and so picking outlier data will lead to erroneous conclusions, and that's why you should focus on trends and no specific data point. You are focusing intensely on a specific datapoint when the underlying phenomena is one which fluctuates.

    Also, it is always possible to cherrypick subperiods which are consistent with your conclusion and reject the overall trends, which also is what you are doing.

    Both of these are classic ways to draw false conclusions. But hey, challenging the orthodoxy should keep the climate scientists on their chops, including the need to better communicate basic principles of statistical analysis to the broader public (like they care, probably just want to read what confirms pre-existing world views ...).

  • I have a study where survey data collected from different departments from within different sites. Analyzing missing data, one site showed higher %.?

    I have a study where survey data collected from different departments from within different sites. Analyzing missing data, one site showed higher %.

    Like other showed 10 to 20% of missing data on my "Y" variable while this specific site showed 30%.

    I am trying to prepare my data for Missing Imputation process.

    1) Should this stop me from doing a Missing Imputation process ?

    2) Would 20%,30% of missing data from my "Y" variable , is some thing I should not use missing data imputation process with ? what do you suggest. 

    My Next plan is to do Factor Analysis after data imputation. 

    Susie Ramisetty-Mikler · University of North Texas HSC at Fort Worth

    You are in a bad situation (sorry!) because you are missing on your Y variable. Your thought #2 is the correct way to go. I have worked with large data sets based on general sample surveys. The whole purpose of conducting research is to predict your Y variable using indep. variables. So if you are going to impute missing data for Y variable, what variables will you consider? As far as my experience goes, we have never imputed "Y" variable. In most cases we only imputed demographic information. For example, income variable which is very important and usually has around 20% missing data or higher based on the ethnic groups (higher for Hispanic). So we used other variables like type of occupation, age, gender, geographical location to impute income. I certainly don't vote for imputing "Y" variable.

  • Akhela Umapathi asked a question in Formazans:
    I was trying to dissolve formazan crystals with acidified isopropanol and it didnt work. Is there any reason for this?

    I have encapsulated my cells using chitosan at different concentrations of 1mg/ml of 0.1M acetic acid, 1mg/ml,0.1 mg/ml. I run MTT at different timepoints of Day0,Day1, Day3 and Day7. at Day 3 time point the formazan formed did'nt seem to dissolve in isopropanol. what might be the reason behind this. I could see the proliferation rate was high. Im using a cell line that grows really fast

  • John Tat added an answer in Antibodies:
    Can i use IP kit for co-IP experiment?

    Can I use IP kit for co-IP experiment? Both are same in primary steps (isolation of specific protein). After isolation the protein complex by IP kit (against 1st antibody) I should run into SDS-PAGE against 2nd antibody of my interest. Is it right or I can’t use IP kit for co-IP experiment.

    John Tat · The Scripps Research Institute

    In principle, you should be able to. But wouldn't it be more efficient to just use a co-IP kit, such as the one from Life Technologies, as the conditions are more optimized?

  • Adib Salandari asked a question in Magnesium:
    who knows the stacking fault energy of Magnesium WE43 alloy?

    this group of Mg alloys containing RE elements which decrease the SFE of the alloy.

  • Ali Daud added an answer in Anomaly Detection:
    What are anomaly detection benchmark datasets?
    I would like to experiment with one of the anomaly detection methods. What dataset could be a good benchmark?
    Ali Daud · http://allthesisonline.com/

    you can use EEG Anomaly Detection System.

    This system is implemented and its details are given here http://allthesisonline.com/thesis/eeg-anomaly-detection-system/

  • How do we summarize SPSS tables to put them in our report according to APA format?

    I have conducted ANOVA, post-hoc, t-test and moderation analysis(through hierarchical regression analysis ) . But I need help , and I want to know the format to summarize and interpret in my report according to APA-6th ed. 

    Marcie Zinn · the NeuroCognitive Research Institute, United States.

    Go to options and choose the table design that most closely fits the one you want. There are  many of them.

    Otherwise, do what I do--type the table from scratch.

    Marcie Zinn

  • Marcie Zinn added an answer in P Value:
    How do I calculate adjusted p value in Dunnett's test?

    Dear All,

    Please help me to solve below mention equation for dunnett test.

    I know how calculate q as per below mention formula.

    q= Mean1-Mean2 / SEDifference

    But I could not understand how to calculate adjusted p value as per below mention formula.

    pValue(adjusted) = PFromQDunnett(q,DF,M).

    Please provide example if possible or reference for the same.


    Marcie Zinn · the NeuroCognitive Research Institute, United States.

    I used to know how to calculate all of these, but now just let my stat program do it for me. If you are low on cash, get a grad student copy of SPSS. Others will do it also.

    Marcie Zinn

  • Hao Wu added an answer in Electroelution:
    How to isolate a specific protein from its SDS-PAGE or Native-PAGE band?

    I want to cut and isolated the protein highlighted in the gel picture I attached. The quantity of protein is not very large. The MW of the protein is around 100kDa. I tried to cut the gel and diffuse it out in PBS buffer but no luck. And I tried to cut it out, put it in a dialysis bag and to electroelute it (using native-PAGE buffer). I did lyophilize it but still could not see any band after that. I also tried that smaller protein with larger quantity (also shown in the gel pic attached with darker band) with both diffusion and electroelution method, but still no luck. Could you please help me with it? Billions of thanks.

    Hao Wu · Baylor University

    @Pavel Májek  

    Thank you so much, I will try this! 

  • Bensahla Talet Lotfi added an answer in Fish Health:
    What is the difference between Fulton's condition factor (K) and b value in length-weight relationship of fish?

    b value in LWR may vary due to combination of one or more factors such as area / season effect, habitat, age, gonadal maturity, fish condition and fish health while K value in Condition Factor are depending on habitat, food source availability, age and sex of different species. They are somehow inter-related but how can we differentiate them?

    Bensahla Talet Lotfi · University of Oran

    i think  b value of WLR is more expressive than fulton cf regarding the physiology and the condition of each specimen given that fulton factor is constant (3) and b factyor can vary with a lot of parameters

  • Nalan Karunanayake added an answer in Python:
    How to compare two photo in Matlab / Python ?

    I am trying to compare two photo, which process is suitable for this ? I use sobel edge detection method for preprocessing. 

    Nalan Karunanayake · Sri Lanka Institute of Information Technology

    the simplest solution is subtraction, and select a range to consider some acceptable differences or use histogram matching   

  • Ahmad Talaei asked a question in Earth's Rotation:
    Does Atmosphere spin with the same Earth angular speed?

    In more detail, does atmosphere at 90 km altitude complete a full rotation at 24 hr? And, if we have a camera attached to the Earth and takes picture of horizontal plane of that altitude every 10 second with a big angle of view, can we combine all the images say for 12 hr and then get the right mesopheric horizontal speed spectrum there or we have to first subtract the effect of earth rotation from all the images?

  • CALL FOR PAPER: III Spanish Workshop on Knowledge Extraction and Validation from Biomedical Database (EVABIO 2011). Http://www.caepia11.es/. November 2011, Tenerife, Spain
    This workshop aims to discuss about all the different techniques
    used to extract useful knowledge from biological and medical databases. But the objective of this workshop goes beyond. We will try to answer to the following questions: How the results obtained can be efficiently validated?, Can the different
    techniques be applied in a easy manner?, are they really useful from the
    biological or medical point of view?. In conclusion, not only the technical quality of
    the different solutions is an important issue. We are insterested too in the real
    application of these solutions. We invite technical papers or reviews about
    data mining, text mining, statistics, mathematics, software tools, validation techniques, ,biological or medical databases, etc. All the contributions, in english or spanish, arewelcome.

    Topics of interest (but not limited to):
    - Microarray technoloqy
    - Clustering. Biclustering. Association Rules
    - Gene networks
    - protein-protein interactions
    - Validation methodology
    - Development and integration of databases
    - Ontologies
    - Software tools
    - Text Mining
    - Genome and sequence analysis
    - Gene expression data analysis
    - Experiences on biological and medical experiments

    Paper will be peer-reviewed and will appear in the workshop proceedings. Selected paper will be publish in a LNAI special edition (http://www.springer.com/series/1244) and an extended version of the best paper will be invited for a special issue of the BioData Mining journal (http://www.biodatamining.org/).

    Important dates:
    May 15, 2011 submission deadline
    June 30, 2011 acceptance notification
    July 31, 2011 camera-ready submission
    November 7, 2011 workshop day

    Workshop organizing committee:
    Jesús Aguilar-Ruiz, School of Engineering, Pablo de Olavide University, Spain
    Norberto Diaz-Diaz, School of Engineering, Pablo de Olavide University, Spain
    Domingo Rodríguez-Baena, School of Engineering, Pablo de Olavide University, Spain

    Workshop program committee:
    Federico Divina, School of Engineering, Pablo de Olavide University, Spain
    Raúl Giraldez Rojo, School of Engineering, Pablo de Olavide University, Spain
    Antonio Perez-Pulido, CABD Developmental Biology Institute, Pablo de Olavide Univesity, Spain
    Francisco Gómez Vela, School of Engineering, Pablo de Olavide University, Spain
    Isabel Nepomuceno Chamorro, School of Engineering, University of Seville, Spain
    Cristina Rubio Escudero, School of Engineering, University of Seville, Spain
    Rocio Romero Zaliz, School of Engineering, University of Granada, Spain
    Ali Daud · http://allthesisonline.com/

    A great work has been done on data extraction in the following given link


    Unified Job Portal is web based system that crawls website related to job portals, parse and extract data from those website and display that data from different websites on single system. This system is useful for candidates who are seeking jobs. Employers are able to create their account and they can post jobs if there are vacancies.

  • What is the concept of gene?

    I have found differents concepts about what is a gene...

  • A. M. Gadian added an answer in WRF:
    Any one working with WRF-ARW model for future climate change projection and downscaling?

    I am working on a project to use WRF-ARW as a regional climate model and  project potential impact of climate change for future periods. But the WRF model doesn't directly ingest the Climate Model out put dat (GCM) from CMIP5   available in ESGF portal directly. So I need some mechanism so as to make this GCM outputs  able to use in WPS the WRF prepossessing system before I run WRF

    A. M. Gadian · University of Leeds

    See http://www.env.leeds.ac.uk/~alan/wiser

    For 1989 - 2000, I am  using era-interim and and ccsm data to drive a global channel model @ 20km and a regional nested domain @ ~ 3km for Europe. This could be applied to other nested domains.  The data will take ~ 1 year to construct, but will then be available for analysis.  The channel domain goes to +/- 68 degrees latitude.  The 20 km data set (initially for 2020-2030, chasm driven runs) will also be available for that region, but explicit convection will not be available. If you have ~ 12 million core hours and 300 Tb of disc space on a fast computer (the job takes 4,000 cores), and you then could do a nest over Africa.

  • Javad Heydari added an answer in Lead Acid Battery:
    What is the analysis of microstructural and mechanical properties of HAZ in resistance welding for lead acid battery ?

    i need to information of process of welding such as , electrical current , heat input and every other things are important

    Javad Heydari · Ferdowsi University Of Mashhad

    tank you for your guidance

    in fact , i need  information from some one who perform processes of welding lead parts in acid battery such as lugs or plates

  • Do anyone know any studies about which polymers (epoxy/vin.est.) that can withstand solvents like kerosene in 135°C for 100 hours without degradation?

    I would like to know which  polymers that can be used in kerosene at high temperatures. Other solvents are interesting as well.

    Eugene Patrick Dougherty · SCA Svenska Cellulosa Aktiebolaget

    How about PEEK, poly ether ether ketone. It's a good engineering plastic useful at even high temperatures, commercially available, and pretty solvent resistant, See, e.g. http://en.wikipedia.org/wiki/PEEK.

  • Bensahla Talet Lotfi asked a question in Fish:
    Does any one know which is the best statistic test to compare growth of fish species from different areas?

    the best and easy test to compare growth of fish from two or more different areas