ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

Browse by research topic to find out what others in your field are discussing.

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  • Marcel M. Lambrechts added an answer in Ethnograph:
    Religious beliefs and rituals: evolutionary adaptations or by-products?

    I want to test whether religious beliefs and rituals are adaptations or by-products of evolution. How can I do that in an ethnographic study? What indicators should I use? Or what methodology should I use to test it?

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France


    Religious beliefs and rituals: what are the underlying proximate origins of these behaviours? Extrasensory abilities to perceive the invisible? Some people claim that animals are better in this than humans.....

  • Raj Kumar added an answer in Metal Complexes:
    Which metal complex (Ni or Zn) shows better results in Cyclic voltmeter studies ?

    Which one is best for CV studies of metal complexes with same type of Aromatic ligand environment.

    Raj Kumar · National College, Tiruchirappali

    Dear Prof. Yuroo V. Geletii,

    I am doing metal complex synthesis with various 3d metals. In that i would like to choose  best metal complex for Cylic voltameter studies. Some time copper complex also didnt shows good Oxdiation and reduction peaks. So only i request through this question.

    Sorry, If anything wrong...

  • Ramappa Kb added an answer in Field Experiments:
    Kindly upload on this page - Random Field Experiments in Agriculture - economic impact related papers?

    I am basically an Agribusiness professional, interested in Random Field Experiment projects. Kindly help me to start with this

    Ramappa Kb · Institute for Social and Economic Change

    Thanks a lot. I am planning for such a technology which can help them to reduce their costs, increases their income and improves soil health. Hope you are kind enough to help me in future. I may forward my proposal, if you can go through and suggest. Kindly, let me know your willingness.

    Anyway, thanks for your kind suggestion.

    Thanks & regards

    Dr. Ramappa

  • Hero M. Ismael added an answer in Biomass:
    What can help prevent fungal adhesion to the inside of 125 ml glass flasks during shake culture assays?

    I want to assess biomass production, but am concerned about attachment of fungal tissue to glass, potentially altering my biomass results. Any suggestions on how to prevent this are welcome? 

    Silanizing the glassware has been suggested - does anyone know of any decent literature regarding the use of growing fungi/other microbes on silanized glassware? 

    Please and thanks! 

    Hero M. Ismael · Salahaddin University - Erbil

    shake the flask vigorously, and also increase the speed of the shaker incubator 

  • Nwonuma Charles asked a question in Bioinformatics:
    Can anyone send to me any publication or book on chemoinformatics and bioinformatic?

    this to enhance my knowledge on this concepts

  • Mesenchymal stem cells derived from the placenta, can be used as a xenograft?

    these cell applied as allograft in many study but their use as xenograft is controversial

  • What is the best way to extract lignin and hemicellulose from a raw sample in preparation of cellulose nanofibers?

    What is the best way to extract lignin and hemicellulose from a raw sample in preparation of cellulose nanofibers?

    Prakashchandra Mervana · Saurashtra University

    I have attaches file for separation of alpha, beta and gamma celluloses from wood and pulp. It is analytical method. 

  • Magda Tsintsadze added an answer in Concepts:
    What is the concept of gene?

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

    Magda Tsintsadze · Ivane Javakhishvili Tbilisi State University


    maybe you'll be interested in reading this:


  • Akira Kanda added an answer in Theoretical Physics:
    I have some opinion about theoretical physics. What is a suitable way to share it with physicist and chemist?

    I have some new interpretation about physics experiment from chemist view. This can explain many basic physics concepts, like charge, interaction or force, movement etc. what is a suitable way to expose my idea?

    Akira Kanda · University of Toronto

    About 2500 years ago, in Greece, people wondered if it is possible to trisect an angle using just a ruler and a compass. This problem was open for 2300 years until Abel showed it is impossible to do that.

    Abel made it clear what it means to use compass and a ruler in geometry. He showed that it is equivalent to solving quadratic equations using analytic geometry. With this clarification, he showed that it is impossible because trisecting an angle is the issue of solving order three polynomial equations using trigonometry. So the reason why Abel managed to solve 2300 years old open problem was simply because he managed to articulate what it means to use compass and ruler in Euclidean geometry.

    What is missing in theoretical physics is this kind of articulate thinking. If theoretical physics can offer some help to more applied field Physicists should  make sure what they are talking about.

  • What is the iso-electric point for Mg-Al spinel sol?

    Do anybody have information regarding iso-electric point for Mg-Al spinel particles in sol.

    V. Alejandro Suárez Toriello · Metropolitan Autonomous University

    In this paper was reported.

  • How can get the information about application and modeling of three dimensional nonlinear mixed Volterra- Fredholm integral equation?

    I want  get from simulation and modeling to nonlinear three dimensional mixed Volterra-Fredholm integral equation.

    Andrey Zahariev · Plovdiv University "Paisii Hilendarski"

    I assume that the integral equation include two integral operators one of Volterra type an other of Fredholm type.

    1. Biology - almost all predator-prey models are based of Volterra type integral equation .

    2. Mathematical - Several integral  inequalities are proved under the idea that the solution of the Volterra type equations is a upper bound for all solutions of hte corresponding inequality and etz...

    For more detailed answer write me an my e-mail: zandrey@uni-plovdiv.bg

  • Oury Monchi added an answer in Brain Physiology:
    How to convert coordinates in MNI space to native subject space?

    In my research I'd like to stimulate Broca's area with TMS. I have coordinates for stimulation in MNI space (I've defined them according to the literature). And now I need to convert them to native subjects' space. How can I do it? 

    Thank you, 



    Oury Monchi · Hotchkiss Brain Insitute, The University of Calgary

    I assumeyou are not using Brainsight as it would do it for you. If you can familiarize yourself with the minc format and minctools (Montreal Neurological Institute) their is a tool to do that.

  • Aamir Habib added an answer in Spectrum Sensing:
    Can anyone share MATLAB code for spectrum sensing for cognitive radio?

    Specially I need code pertaining to energy detection and a brief explanation on the relationship between threshold and probability of detection.

    Aamir Habib · Institute of Space Technology

    % This code is to plot receiver operating characteristic curve for simple energy
    % detection, when the primary signal is real Gaussian signal and noise is
    % addive white real Gaussian. Here, the threshold is available
    % analytically.
    % Code written by: Sanket Kalamkar, Indian Institute of Technology Kanpur,
    % India.

    close all
    clear all
    L = 1000;
    snr_dB = -14; % SNR in decibels
    snr = 10.^(snr_dB./10); % Linear Value of SNR
    Pf = 0.01:0.01:1; % Pf = Probability of False Alarm
    %% Simulation to plot Probability of Detection (Pd) vs. Probability of False Alarm (Pf)
    for m = 1:length(Pf)
    i = 0;
    for kk=1:10000 % Number of Monte Carlo Simulations
    n = randn(1,L); %AWGN noise with mean 0 and variance 1
    s = sqrt(snr).*randn(1,L); % Real valued Gaussina Primary User Signal
    y = s + n; % Received signal at SU
    energy = abs(y).^2; % Energy of received signal over N samples
    energy_fin =(1/L).*sum(energy); % Test Statistic for the energy detection
    thresh(m) = (qfuncinv(Pf(m))./sqrt(L))+ 1; % Theoretical value of Threshold, refer, Sensing Throughput Tradeoff in Cognitive Radio, Y. C. Liang
    if(energy_fin >= thresh(m)) % Check whether the received energy is greater than threshold, if so, increment Pd (Probability of detection) counter by 1
    i = i+1;
    Pd(m) = i/kk;
    plot(Pf, Pd,'linewidth',2)
    hold on
    grid on
    %% Theroretical ecpression of Probability of Detection; refer above reference.
    thresh = (qfuncinv(Pf)./sqrt(L))+ 1;
    Pd_the = qfunc(((thresh - (snr + 1)).*sqrt(L))./(sqrt(2).*(snr + 1)));

    plot(Pf, Pd_the, 'r-')
    xlabel('probability of false alarm')
    ylabel('probability of detection')
    hold on
    grid on

    Can someone provide a MATLAB code for CR spectrum sensing?. Available from: https://www.researchgate.net/post/Can_someone_provide_a_MATLAB_code_for_CR_spectrum_sensing [accessed May 30, 2015].

  • What are the alternate names for essential oils isolated from aromatic plants?

    Essential oils are also known as aromatic oils or fragrant oils or ethereal oils. What are the other names and in different languages? 

    B.R. Rajeswara Rao · Central Institute of Medicinal and Aromatic Plants

    Dear friends

    Thanks for your informative posts. I am interested to know the names of "essential oil" in different languages.

  • Magda Tsintsadze added an answer in JavaScript:
    How can I open an image with a new separate window larger than the original using JavaScript codes only JQuery without Html and JavaScript?

    I need your urgent help to fix this problem in web design, please.

    I need to open an image with a new separate window larger than the original using JavaScript only and only without JQuery Just Html and JavaScript.

    Magda Tsintsadze · Ivane Javakhishvili Tbilisi State University

    new_span.append('<a id="imglink" href="'+ new.link +'" target="_blank"><img src="' + new.url +'" height="" width="" /></a>');

    $('#imglink').click(function() {

    window.location = $.myURL("index", $(this).attr("href"));


  • Surya Sujathan added an answer in Biogas:
    What should be the size of BioGas Digestor to get 1 Mcub of gas/hr for cow dung as input?

    I want to estimate approximate size of digestor and daily input requires to generate biogas of 1 CubicMeter/hr. Please suggest.

    Surya Sujathan · Indian Institute of Technology Delhi

    If i have understood your question correctly this is how you can find out :

    Biogas generation of 1m3/hr would mean approx, 24m3 in a day.1kg of cowdung produces approx .04m3 biogas, which gives around 600kg of dung. This dung has to mixed with equal amounts of water which will be the daily feed volume.If you can figure out hydraulic retention time for the cow dung,that multiplied by daily feed volume would give total digestor volume.

  • Nader Aghakhani asked a question in Nursing:
    How do nurses communicate with together more effectively?

    We know that communication is the transfer of information between or among people. The practice of nursing utilizes constant communication between the nurse and other persons.

    I think that communication between the nurses with together has many benefits.

    How do nurses communicate with together more effectively?

  • Nwonuma Charles added an answer in Coagulants:
    May I request for recent journals on removal of an anionic dyes from aqueous solution by using animal and plant extract (Coagulants)?

    journals on coagulations is needed by Engr.(Mrs) C.F. Okey-Onyesolu as soon as possible

    Nwonuma Charles · Landmark University

    Kindly google for Akpor OB may you can get one of his publication in dye removal

  • Ahmed Ali added an answer in Histopathology:
    Any advice on a histopathological tumor-like structure at the tip of the prepuce?

    Ulcerative wart-like structures were observed at the tip of the prepuce of 3.5y male camel  associated with inflammation and edema. Histopathology revealed fragments of polypoid partly ulcerated skin with actively inflamed verrucas wart. No clear cut-evidence of malignancy is present.

    Does anyone have any suggestions or can advise on this case?

    Ahmed Ali · Qassim University

    Thank you Dr Bamaiyi

  • Hero M. Ismael added an answer in Disinfection:
    Whats the best culture medium/agar to grow fungi only?

    Fish Egg disinfection research at the IGB Berlin.

    Hero M. Ismael · Salahaddin University - Erbil

    PDA Potato Dextrose Agar  or CDA (czapex Dox Agar) but you should add antibiotic to prevent bacterial growth (chloramphenicol or streptomycin)

  • How can we attain 100% double digestion results for a vector?

    I am cloning a gene into a pET28a vector. I used NEB enzymes NheI and HindIII to  to double digest my insert and the vector using 2.1 NEB buffer. Incubation was done at 37 degree overnight (10 hours). Gel extraction was done for both double digested insert and vector. The digestion looks clean and clear in the gel. This was followed by ligation at 16 degree(10-12 hours).

    During transformation a control was set up with double digested vector in XL1 blue cells. I found a number of colonies after incubation, Whereas blank XL1 blue cells did not grow on kanamycin plates as per expectations.

    This shows un even double digestion of the vector.

    How can we improve this scenario to overcome the ambiguity over cloning results? 

    Gaurav Kumar Singh · IIT Kharagpur

    Thanks alot for your feedback. I guess, It's a case of incomplete digestion by one of the enzymes. 

  • Kuberan Ganesan asked a question in Pandalidae:
    Gonopore development of deep sea caridean shrimp particularly Pandalidae family has been reported?

    Can anybody attach me a publication of gonopore development or sex change in Caridea-Pandalidae family has been reported.


  • Nishant Jaiswal added an answer in Meta-Analysis:
    How can I conduct a systematic review and meta-analysis of clinical trials?

    I would like to conduct a meta-analysis which evaluates the success rate of a dental treatment as dichotom , that it succeeded or failed.

    Success : No pain, no problem, radiographically good, healed tissues etc.

    Failed : Pain, swelling, unhealthy tissues, radiographically bad, missing teeth (extraction).

    1. As for my question, can I enter the data of the missing teeth ( survival) together with the other failed group data in the same forest plot?

    2. OR or RR ? Which one should I prefer for the effect size ?

    thank you very much

    Nishant Jaiswal · Postgraduate Institute of Medical Education and Research

    please consider downloading the REVMAN 5.3.5 software from cochrane.org and then go through the cochrane handbook for systematic reviews of intervention. This will give you a detailed methodology for doing a systematic review for intervention. 

    a good research question in PICO (T) format forms a strong base for a good review. It should be specific, relevant and required.

  • Nwonuma Charles added an answer in Oxidative Stress:
    How can we explain the significant decrease in GST activity, while there is no oxidative stress and the GSH levels are normal ?

    How can we explain the significant decrease in GST activity, while there is no oxidative stress (significant decrease in MDA levels) and the GSH levels are normal ?   also, SOD levels showed significant increases , while catalase activity showed significant decrease.

    Nwonuma Charles · Landmark University

    you cannot rule out oxidative stress due to significant low level of MDA. it could be the onset of oxidative effect hence GST serve as the first line of defense against the oxidative stress. Another explanation is that decrease in SOD could be as a result of saturation due to overwhelming peroxidation hence GST come into play. Where did you carried out the test, tissue or serum? Try to think in this line you may get the answer.

  • Yen Chun yu added an answer in Dynabeads:
    For how long can I keep viable Tregs in incubator before flow cytometry?

    Hi, I would like to isolate and expand Tregs from human lymphocytes using Dynabeads by Life Technologies. For how long can I maintain the Treg in an incubator before analysis by flow cytometry? As I have read that freeze/thawing Tregs will alter the surface markers and hence will impede accurate flow cytometry analysis

    Yen Chun yu · Academia Sinica

    Generally, we use commercial product that purchased from BioLegend(#421403). And we stop at the step after treating cells with Fix/Perm solution. If you want to use the non-commercial buffer, I can looking for me seeing I can find the protocol that we used before.

  • Saeed Rahmati asked a question in Adaptive Control:
    Could anyone tell me some of the adaptive algorithms like RLS??

    I came across this question: ''Name some of the adaptive algorithms like RLS?

    I'd appreciate it if someone could help me with this question.

  • Real time image histogram specification?

    Have anybody experienced with real time grayscale image histogram with opencv? I have used it for stereo vision project to make equal two gray images intensities. Is there a better way to make equal intensities of two identical images taken from two cameras for stereo vision computation. 

    Mohammad Tahir Ahmed Shoani · Universiti Teknologi Malaysia

    You can try the statement "Mat::setTo". The following is taken from the OpenCV 2.4.8 reference manual, page 31:

    Sets all or some of the array elements to the specified value.
    C++: Mat& Mat::setTo(InputArray value, InputArray mask=noArray() )
    value – Assigned scalar converted to the actual array type.
    mask – Operation mask of the same size as
    this. This is an advanced variant of the
    Mat::operator=(const Scalar& s) operator.

    You can use it to set both images to the same scalar values.

    The attached link is for the latest manual (OpenCV 2.4.11)

    I hope that helps.

  • Are there any Java Script codes to deal with pictures on an HTML page?

    Could anyone give me some tips or codes to enlarge pictures and open them in a new window using programming language/JavaScripts codes with HTML and CSS?

    Magda Tsintsadze · Ivane Javakhishvili Tbilisi State University

    here is your code:

    the html:

    <div id="sse1">
    <div id="sses1">
    <li><a href="#">Javascript Menus</a></li>
    <li><a href="#">Horizontal Menus</a></li>
    <li><a href="#">Web Menus</a></li>


    var sse1 = function () {
    var rebound = 20; //set it to 0 if rebound effect is not prefered
    var slip, k;
    return {
    buildMenu: function () {
    var m = document.getElementById('sses1');
    if(!m) return;
    var ul = m.getElementsByTagName("ul")[0];
    m.style.width = ul.offsetWidth+1+"px";
    var items = m.getElementsByTagName("li");
    var a = m.getElementsByTagName("a");

    slip = document.createElement("li");
    slip.className = "highlight";

    var url = document.location.href.toLowerCase();
    k = -1;
    var nLength = -1;
    for (var i = 0; i < a.length; i++) {
    if (url.indexOf(a[i].href.toLowerCase()) != -1 && a[i].href.length > nLength) {
    k = i;
    nLength = a[i].href.length;

    if (k == -1 && /:\/\/(?:www\.)?[^.\/]+?\.[^.\/]+\/?$/.test) {
    for (var i = 0; i < a.length; i++) {
    if (a[i].getAttribute("maptopuredomain") == "true") {
    k = i;
    if (k == -1 && a[0].getAttribute("maptopuredomain") != "false")
    k = 0;

    if (k > -1) {
    slip.style.width = items[k].offsetWidth + "px";
    //slip.style.left = items[k].offsetLeft + "px";
    sse1.move(items[k]); //comment out this line and uncomment the line above to disable initial animation
    else {
    slip.style.visibility = "hidden";

    for (var i = 0; i < items.length - 1; i++) {
    items[i].onmouseover = function () {
    if (k == -1) slip.style.visibility = "visible";
    if (this.offsetLeft != slip.offsetLeft) {

    m.onmouseover = function () {
    if (slip.t2)
    slip.t2 = clearTimeout(slip.t2);

    m.onmouseout = function () {
    if (k > -1 && items[k].offsetLeft != slip.offsetLeft) {
    slip.t2 = setTimeout(function () { sse1.move(items[k]); }, 50);
    if (k == -1) slip.t2 = setTimeout(function () { slip.style.visibility = "hidden"; }, 50);
    move: function (target) {
    var direction = (slip.offsetLeft < target.offsetLeft) ? 1 : -1;
    slip.timer = setInterval(function () { sse1.mv(target, direction); }, 15);
    mv: function (target, direction) {
    if (direction == 1) {
    if (slip.offsetLeft - rebound < target.offsetLeft)
    this.changePosition(target, 1);
    else {
    slip.timer = setInterval(function () {
    sse1.recoil(target, 1);
    }, 15);
    else {
    if (slip.offsetLeft + rebound > target.offsetLeft)
    this.changePosition(target, -1);
    else {
    slip.timer = setInterval(function () {
    sse1.recoil(target, -1);
    }, 15);
    recoil: function (target, direction) {
    if (direction == -1) {
    if (slip.offsetLeft > target.offsetLeft) {
    slip.style.left = target.offsetLeft + "px";
    else slip.style.left = slip.offsetLeft + 2 + "px";
    else {
    if (slip.offsetLeft < target.offsetLeft) {
    slip.style.left = target.offsetLeft + "px";
    else slip.style.left = slip.offsetLeft - 2 + "px";
    changePosition: function (target, direction) {
    if (direction == 1) {
    //following +1 will fix the IE8 bug of x+1=x, we force it to x+2
    slip.style.left = slip.offsetLeft + Math.ceil(Math.abs(target.offsetLeft - slip.offsetLeft + rebound) / 10) + 1 + "px";
    else {
    //following -1 will fix the Opera bug of x-1=x, we force it to x-2
    slip.style.left = slip.offsetLeft - Math.ceil(Math.abs(slip.offsetLeft - target.offsetLeft + rebound) / 10) - 1 + "px";
    changeWidth: function (target) {
    if (slip.offsetWidth != target.offsetWidth) {
    var diff = slip.offsetWidth - target.offsetWidth;
    if (Math.abs(diff) < 4) slip.style.width = target.offsetWidth + "px";
    else slip.style.width = slip.offsetWidth - Math.round(diff / 3) + "px";
    } ();

    if (window.addEventListener) {
    window.addEventListener("load", sse1.buildMenu, false);
    else if (window.attachEvent) {
    window.attachEvent("onload", sse1.buildMenu);
    else {
    window["onload"] = sse1.buildMenu;


    /*You can decorate the menu's container, such as adding background images through this block*/
    background-color: #222;
    height: 38px;
    padding: 15px;
    border-radius: 3px;
    box-sizing: content-box;
    margin:0 auto;/*This will make the menu center-aligned. Removing this line will make the menu align left.*/
    #sses1 ul
    position: relative;
    list-style-type: none;
    border-bottom:solid 1px #6C0000;
    #sses1 li
    list-style-type: none;
    /*CSS for background bubble*/
    #sses1 li.highlight
    border-bottom:solid 1px #C00;
    z-index: 1;
    position: absolute;
    #sses1 li a
    box-sizing: content-box;
    padding-top: 8px;
    margin: 0 20px;/*used to adjust the distance between each menu item. Now the distance is 20+20=40px.*/
    color: #fff;
    font: normal 12px arial;
    text-align: center;
    text-decoration: none;
    float: left;
    display: block;
    position: relative;
    z-index: 2;

  • Kuberan Ganesan asked a question in Pandalidae:
    Gonopore development of deep sea caridean shrimp particularly Pandalidae family has been reported?

    Can anybody attach me a publication of gonopore development or sex change in Caridea-Pandalidae family has been reported.


  • Can anyone identify this columbellid gastropod?

    Collected from the west coast of India (Arabian sea), this intertidal columbellid Pyrene sp ????? looks close to Pyrene flava and P. punctata. Still, closer observation on the shell shows

    brownish shell darkening at the whorls with almost rectangular white markings that alternate in position; white apex in almost all shells but dark brown in fresh shells; pale lines run vertical in the last whorl with characteristic 10 horizontal spiral ribs; columella is smooth; outer lip in aperture contains 7 folds or plicae; inner side purplish in colouration. 

    Shell height 28mm; width 11mm; aperture height 18mm; aperture width 3mm

    Would be informative if someone could identify and share materials related to this species


    Deepak Samuel Vijay Kumar · National Centre For Sustainable Coastal Management

    Thanks for the inputs Dr Marta

    best regards