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  • Lynne Barga added an answer in Qualitative Research:
    Can anyone help with methods and measurements used when using quantitative models for qualitative research?

    I would appreciate any advice on how to defend the use of Fishbein's 'integrated model of behavioural prediction' when using qualitative research only for a thesis. Also is it possible to extend a quantitative model based on research findings from a qualitative research?

    Lynne Barga · University of North Texas

    Pauline, it might be helpful if you differentiate between qualitative methods and qualitative research. Shujaat makes a good point that the scope and aims of qualitative and quantitative research are very different, but you can creatively adapt the methods of either to serve your project, as long as you observe the fundamental assumptions of the models.
    It seems to me that by saying your interview data can “only” focus on the nature of the users’ attitudes and motivations, or that it can “only” tell you why someone has a particular attitude, you are undervaluing the very richness of your qualitative data! Indeed, the purpose of qualitative data is to provide just such rich insights at the individual level, which can speak to an understanding of human motivation – no small accomplishment!

  • Garima Joshi asked a question in Grid:
    Scheduling in grid environment

    please provide me with the latest research paper published in heterogeneous load balancing scheduling using grid environment

  • Ramanand Jha added an answer in Laser:
    Is it possible to observe sustained interference pattern from two independent laser source?


    Ramanand Jha · Skyline Institute of Engineering & Technology, Greater Noida (UP) INDIA

    I think, it is always possible to have interference of two waves having same polarization for ultra-short period even if they are coming from the two independent sources of light. But the question whether it will be a sustained interference or not. 

  • Niklas Manz asked a question in Comp:
    Figure is in a different position in the dvi and the final pdf file

     I have a weird problem which I never had before and I can't figure out why. I am comping the dvi and everything looks good. When creating the pdf file, all figures are moving down into the figure caption. Any idea?

    The figures stay in the same place if I create first a ps and then a pdf. So, I found a solution but the questions remains why a direct step from dvi to pdf does not work.

  • Anna Ilek added an answer in Forest:
    Does anyone know of any references on tree species effects on forest hydrology?
    I am computing nutrient fluxes in the soil profile in a common garden experiment. I have for this modeled water fluxes in the different tree species stands and found differences from throughfall to deep water seepage (below the rooting zone). I was hoping to find some studies that have compared forest hydrology parameters under different tree species cover, preferably on the same site but I haven't found anything really conclusive yet. Any suggestions?
    Anna Ilek · University of Agriculture in Krakow

    In this article are information about effect of stand species composition on the water storage capacity of the organic horizons of forest soils. Maybe you can use these information

  • Ganesh Narayanan added an answer in Polymerization:
    Why would the XRD peak of a polymer diminish drastically?

    In one of my electrospun polymer/low molecular weight blend sample, the crystalline peaks for the semicrystalline high molecular weight polymer, almost diminishes, even with 90:10% blend. Anyone knows why is that? 

    Ganesh Narayanan · North Carolina State University

    Sorry, I could not follow up for quite some time. Here are the raw materials. 

    polymer=Polycaprolactone (density is slightly higher)

    Filler=Beta cyclodextrin

    Filler %=10 to 40%. peak intensity of PCL decreases right on from 10%

    Fibers prepared by wet electrospinning. Solutions were prepared at high temperatures (80C) but electrospun at room temperatures. 

    @Ejaz ahmed, I can send the files, but what format would like it to be in? @ Nisha I hope I had given complete information. 

  • Can anyone help with an initial temperature value transported from a frequency-stationary solver to a time-dependent solver?


    Can someone help me solve this issue please?

    I have a multi-physics model (Magnetic field + heat transfer). I solve this model with Frequency-Stationary solver. Everything is fine with this part. Then I want to use the initial temperature values I obtained through solving my initial problem and feed them to a new solver (second part). In the second part I only solve heat transfer with different boundary conditions and I want to solve it in time domain.

    I have followed the instructions carefully. In the dependent variable section, I have chosen solution 1 as the initial values for solution 2. I can solves the problem. But when I look into the temperature values in solution 2 at time 0, they are different from the temperature values I had got from the first solution. I can send you my model if you have time to look into it. I just want to know if I am missing something that my temperature values from the first study are not being transferred to my second study correctly.

    Thank you very much for your time,

    Mohmmad Al-dweikat · Tsinghua University

     expand your time dependent solver , look for dependent values and choose initial based 

  • Is it compulsory to exclude all Cq/Ct values more than 30?

    Does error (difference of less than 3 degree Celsius) in annealing temperature have any role in getting a higher Cq/Ct?

    Pietro Pilo Boyl · University of Bonn

    I see Charles... let me suggest you something... change the primers. Such a low annealing temperature is very dangerous, you want to be at least over 55 °C, better around 58-60 °C, which means 50-60% GC content in the primer. Moreover, I always suggest when designing primers to have at least 3 G,C bases in the last 5 nucleotides at the 3' end of your primer, possibly ending your primer with GG or CC: this is where the Taq polymerase starts elongating and the free energy (dG ) of the 3' end of the primer (last 7-8 bases) should be around -13 to -15.

    Anyway, for your reassurance, run your qPCR reaction at 49 °C on the gel... and check what you have there... I don't think you'll see a single band of the expected size of the amplicon...

  • Stefano Quattrini added an answer in Space:
    Is there more than one theory of gravity that can demonstrate compatibility with the Einstein equivalence principle?

    I am looking for theories that give different observations, i.e. that are measurably different.

    • Observations must match Minkowski space in free space.  This is a theoretical question.  Not looking for radical theories that would violate Minkowski space.
    • Each theory must be able to demonstrate that observations in an accelerated elevator in free space are the same as in an elevator sitting on a planetary surface.
    • Please show how multiple elevators over an extent of space are integrated to give the different observations of each theory, i.e. how the same local observations integrate differently.
    Stefano Quattrini · Sapienza University of Rome


    it is not the double slit experiment which is the same for fermions and photons, here I'm talking about something which is strictly a property of Photons. The division of the wave packet (PENROSE) and its detection far away, buf very far away is not an invention, it creates huge problems to the tensor theory which is local.

    In the case a very powerful light a beam of 1010 gamma photons, passing near a gravitating object, bended the space time through which it passes, according to their energy content, it would change the gravitational fields around itself also, it would Exchange energy with the massive gravitational object, and lose its energy. For example  in the phenomenon of gravitational lensing its frequncy would change..this is really a problem...

  • How would you analysis Di-2-Ethylhexyl Phthalate (DEHP) and Mono-2-Ethylhexyl Phthalate (MEHP) in Whole Blood?
    Any suggestion on how to go about an analysis of phthalates concentration in whole blood. How would I carry out the analysis in ELISA or any other possible methods (without chromatography)?
    Carlos A. Rosado-Berrios · Arkansas State University - Jonesboro

    You need some kind of chemical analysis to determine the concentration. The ELISA can help you to establish a relation between the concentration of the phthalate and the amount of enzyme or the intensity of the immune response to a phthalate specific concentration.

  • Maria Sancho-Tello asked a question in Histology:
    Eye fixation for histology

    How can I get the retina remains stuck in its place during histological process?

  • Can anyone suggest some helpful literature in Differential Scanning Calorimetry, Tg and polymers?

    Hello guys!

    I'm working with DSC and emulsions of PVA with CNTs. And I'm having some doubts about where I have to locate the Tg in the curves. Can somebody give some advice or maybe suggest me some literature to consult?

    Thank you!!

    Ana L. Rodríguez Zúñiga · Costa Rican Institute of Technology (ITCR)

    Thanks to all! I apologize because I'm working in other thing by the moment. But soon I have to come back with the DCS and Tg interpretation, so I'm going to consult all your recommendations and I will comment it again. I really appreciate your help and interest.

    Kind regards,


  • Anya Metcalfe asked a question in Sexual Dimorphism:
    Unit for analyzing sexual dimorphism of lepidoptera?

    Looking through the literature, I am seeing studies that have used either weight or forewing length for looking at sexual dimorphism. Both seem to work, but in my case, I'm getting slightly different stories depending on the unit. Females tend to be heavier, likely b/c of their reproductive systems, and males tend to have longer wings. The two variables are obviously related to one another. My question is, does is matter which variable I used for analyzing dimorphism? Is one more standard than the other, or should I just use both?

  • Li-Zhen Fan added an answer in Activated Carbon:
    Electro chemical characterization of activated carbon samples

    Which binder is suitable for taking Cyclic Voltammetry studies of Activated carbon powders if it is going to be applied in supercapacitors?PTFE or Nafion?What is the best method for coating carbon samples over steel plate for CV studies?

    Li-Zhen Fan · University of Science and Technology, Beijing

    PTFE or PVDF, either binder is ok for supercapacitor. I never used Nafion. That is the normal method to coating, you can read from any paper. mix active materials, carbon black, PVDF in NMP solution, then casting on SS plate, then drying.

  • Arno Gorgels added an answer in Philosophy-Theology-Science public:
    Was twentieth century science atheistic?
    As from 1967, at the time when I was being taught Special Relativity, I got the impression, indicated by my physic's professor, that I should accept atheism as a pillar of modern science. Was that impression correct? Cantor's Universe, that I teach, allows in principle a theistic view. Now, I wonder: What is the contemporary opinion on this subject? I am interested to hear some opinions. What is yours? Do you practice science from an atheistic point of view?
    Arno Gorgels · Principia Naturae

    Harry, dan moet ik het boek zelf weer lezen en het zaakje op een rijtje zetten. Daar heb ik absoluut geen tijd voor. 

  • What does the E-value exactly mean and what does (1e-63) represent?
    As I read its an expected value and the lower the value minimum represents alignment by chance. But I could not understand what the representation (for example, 1e-63 etc.) is actually denoting.
    Aras Rasul · Bangor University

    why small E-value better score?

  • What property of the material determines the working voltage (working voltage window) of the anode material for Lithium ion batteries?

    I have noticed that TiO2, MnO2 and Si are working with very different end voltages, i.e. Si stops at 0V, TiO2 stops at 1V etc. I understand that the end voltage is to protect the material from structural irreversible change. What I do not understand is when you take TiO2 for example, what properties, in physics terminology, could determines/affects this end voltage of the material?

    L. A. Montoro · Federal University of Minas Gerais


    1. your first question isnt clear for me. 

    2. Usually the Li battery materials (e.g. LiCoO2) are not submitted to a deep discharge (complete Li extraction). This situation can induce a serious coulombic efficiency loss with a fast capacity fading. These effects are often attributed to irreversible structural modifications ... in both structure or electronic states. You are right !! we left part of Li to maintain the structural stability. e.g. the LiCoO2 operates efficiently until Li0.5CoO2. A half of lithium is left in the structure to attain a high reversibility. LiCoO2 have a theoretical capacity of 274 mA.h/g, but a reversible (practical) capacity by 140 mA.h/g. Different materials have different reversible Li ranges ... The new Li(CoNiMn)O2 or the Li-excess layerd materials can operate with capacities as high as 250 mA.h/g ... with a large Li reversible range.   

  • Peter T Breuer added an answer in Puzzle:
    How do you randomize a 9 x 9 grid with 81 cells to populate between 10 and 21 numbers in Visual Basic?

    I am trying to populate a Sudoku grid by placing randomized numbers between 1 to 9 throughout the 81 celled grid. I already have a solver that solves a puzzle but I want to use a button to randomly populate the grid to start a new puzzle each time the button is clicked. I am not fluent in VB code and I have been searching for an algorithm to complement my needs. I used backtracking to solve the puzzle but I need to use random to populate the grid for the beginning of the game. I have attached a copy of my public class and my backtracking algorithm. How do I get random numbers to populate my start button?

    Peter T Breuer · Birmingham City University

    Why don't you do what has been suggested to you?

    (I can tell you why you should not as is, but your response is the interesting one).

  • Kateřina Šumberová added an answer in Rumex:
    Can anyone help in identifying of this plant?

    This plant was collected from orchards, about 180 cm in height, i think it is one type of Rumex

    Kateřina Šumberová · Institute of Botany of the ASCR

    Dear Mohamed,

    yes, it is certainly some species of Rumex - it is well visible from the photos. For precise identification of the species it would be necessary to have some details, e.g. how the lower leaves (leaf rosette) look like (when available in the time of flowering/fruiting), very detailed photos of fruits (made with the use of dissection microscope), etc. Probably the best choise would be if you now take some local flora or identification key and try to check the characteristics of particular species. You may need lens or dissection microscope but it is still more easy way than to take the photos of fruits in very high quality and wait if somebody will identify  the species exactly.


  • Daniel Wright added an answer in Mac:
    Stats & Graph Programme(s) for Mac

    Can anyone recommend good statistical and good graphics apps / programmes for a Mac? (It would be helpful, if you could describe your experience with them.) Thanks.

    Daniel Wright · ACT Inc.

    It depends what you want.

    R has a Mac version, is free, does tons, and is used by lots of people, but has a steeper learning curve than other packages. You can download it from http://cran.r-project.org/. There are lots of "getting started with R" websites, papers, and books (http://www.r-project.org/doc/bib/R-books.html). Kamala London and I wrote a chapter on it here (http://www.uk.sagepub.com/upm-data/26922_Wright_Chapter_One.pdf), but there are lots of other resources around. 

  • T. Ansah - Narh asked a question in Python:
    SCATTER PLOT: Comparing two different datasets

    I have two different fits files with different shapes (i.e. (310, 256, 256) & (560, 4, 786432)). How do i make two scatter plots to compare them using python? That's plotting one data on the other.

  • Daniel Page added an answer in STRING:
    How to turn a graph into a string(of {0,1})?

    i wanted to know how could i represent a graph using a string; i mean the string should contain all the information to reconstruct the graph(not exactly the original one if it's not feasible but maybe a similar graph) of course.

    Daniel Page · University of Manitoba

    You'll find that it isn't too difficult to find other ways to encode a graph as a binary string.  Why?  Because, of what a graph is in terms of its combinatorial description.  It's combinatorial description is a set of vertices and a set of pairs of vertices.  If you have any way to recognize when you start/stop reading the next bit of information, you can do it pretty easily if you lay out the scheme.  The "natural" way is what other posters have suggested with an adjacency matrix or an incidence matrix (but it definitely doesn't have to be this way).

    The problem with representations gets interesting when it comes to what kind of questions you want to answer (i.e., decision problems) about the encoded graph.

  • Rodrigo de Carvalho asked a question in Clustering:
    Clustering methods

    What would be the state of the art method to capacitated clustering in the euclidean space (the cluster representation is given by its center)? This problem is combinatorial and non-linear, hence the use of exact methods are not recommended.

  • Peter T Breuer added an answer in Research Projects:
    Can anyone help with methods for the planning of order picking systems?

    When working on a research project about methods for the planning of order picking systems we found quite a range of articles, papers and books in German. The search in various databases for international sources did lead only to one hit (1 Italian Diss.). I consider it to be highly unlikely that there are no such publications in other countries but assume that we didn´t find the right search terms (despite we tried everything we could image).

    So if there is anybody who knows international publications about methods for the planning of order picking systems (structures and/or processes) I would be grateful if you could give a hint. Many Thanks already in advance.

    Peter T Breuer · Birmingham City University

    Oh ... "order" as in "request from a customer", not as in "alphabetic or numeric order"!

    If you had provided your explanation in the question, I am sure many people would have answered you. So this question should be sited in "manufacturing process design", perhaps? Or "industrial architecture"?

    Did you really mean "order picking"? That does not strike me as English :-(. I can understand "order satisfying". Or  is that not meant to be a single adjective to "system" .. should it really be a "picking [from shelves and pallets] system" "for orders". In that case I canot see what the word "order" has to do with it at all, and perhaps you really are asking for advice on designing a warehouse so that its storage areas are going to be properly accessible to automated systems that (deposit and?) retrieve items on demand.

    "On-demand automated warehouse systems" would make even more sense to me.

    Yes, Google has lots on "automated warehousing systems design and layout". Is that the kind of thing you were looking for? I'm sure that if you take some of your existing references and put in key phrases from their bibliographies, you'll soon scope out the field.

  • William Carrasco added an answer in Literature:
    What are the requirements for literature to be universal?
    Literature in multiforms - novels, poems,etc - can be universal, or can be local. What are requirements and limitations for literature to be universal?
    William Carrasco · City University of New York - Hunter College

    I agree with Krishnan.  That's a good,  hermeneutic stance in my opinion.

  • How to explain the Raman intensity enhancement of multi-walled carbon nanotube after functionalization ?
    I have compared Raman spectra of pristine MWCNT with MWCNT functionalized by carboxylic group. Both of them were purchased from one commercial supplier. I found that the Raman intensity of the functionalized MWCNT was significantly enhanced with respect to pristine MWCNT. Interestingly, the RBM becomes visible in MWCNT-COOH. Anybody could explain these observations?
    Ana L. Rodríguez Zúñiga · Costa Rican Institute of Technology (ITCR)

    Hello. I was searching information about this fenomena, because in my Raman spectra I try to compare pristine MWCNTs against others with -OH groups attached, we bought these carbon nanotubes and we are just trying to characterize them. And the situation is the same that yours. The G band of the functionalized MWCNTs is higher than the pristine. I'm a little confused because some workers used the G/D ratio and in other they used the D/G ratio; could you help me and tell me which is the correct. 

  • Thomas Marcussen added an answer in Primer:
    Can you help with designing higher taxa-specific primers using Primer Blast?

    I am trying to design a primer pair for rbcL that could specifically amplify bryophytes using primer BLAST, but I'm confused. If I enter sequence/GenBank Accession of one template, for ex., Physcomitrella and choose "Specificity check enabled" and "Organism=Bryophyta", won't it get amplified for other mosses? 

    Thomas Marcussen · Norwegian University of Life Sciences (UMB)

    Degenerate primers is the way to go, but avoid degenerated sites near the 3' end (primer binding site). Also, design and order at least two forward and two reverse primers. The external primer pair can be used in the PCR and the internal primer pair for sequencing (or for nested PCR).

  • Do you have information on Stochastic processes of tumor growth?

    Does anyone know anything about the stochastic process of tumor growth? Especially study tumor growth with eden model or gompertzian model or lagestic model?
    are this kind of models useful for treatment?
    how we can control internal and external noise of tumor?
    what is the last news of it?

    Hafayed Mokhtar · Université de Biskra, Algeria,

    Dear Professor Elmira,

    I'am working on stochastic control problems, I try to help you and give some papers on your model.

    Best regards

    Mokhtar Hafayed

  • How do you add signaling direction to a protein-protein interaction network?

    I have a large protein-protein interaction based on orthology with experimental PPIs. I want to transform my network to signalling pathways. The NetSearch algorithm can be applied for this but I am looking for much robust solution/software for this.

    J. Harry Caufield · Virginia Commonwealth University

    I would also like to find software to handle this problem well - I'm assuming that you plan to start with the predicted PPI network and map it to known signalling pathways rather than defining new pathways. There are a few Cytoscape plugins which kind of do what you're talking about. There's the Pathway Scoring Application (http://apps.cytoscape.org/apps/pathwayscoringapplication) and NetAtlas (http://apps.cytoscape.org/apps/netatlas), though depending on the availability of expression data, neither option may provide what you're looking for. You could also just use (or reverse-engineer) the KEGG mapper (http://www.genome.jp/kegg/tool/map_pathway2.html) if you have unique protein IDs.