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  • Sylvia Patrick asked a question in Devices:
    What are the problem faced by left-handed user in using facilities and devices?
    • I want to know specifically problem in tabloid chair for left-handed user and i want to know what are the solution had been done to overcome this problem for the tabloid chair for those left-handed user. The new design of tabloid chair for left-handed
  • Gyan Chandra Chauthwani added an answer in Theoretical Physics:
    I am stuck with a complex integration given in the file attached herewith. Can any please suggest me the way to solve such integration?

    I am stuck with a complex integration given in the file attached herewith. Can any please suggest me the way to solve such integration?

    Gyan Chandra Chauthwani

    @ all, 

    If no general solution of this integral exist, then how the zeros of this function are calculated?

  • Taha Ibrahim added an answer in Abaqus:
    Where can I get complete list about soil analysis in abaqus ?

    Does anyone know where can I find examples for vertical drainage analysis in abaqus? 

  • Heidy Robles added an answer in Dialogical Self:
    Does anyone know of research that has combined Bakhtinian dialogic and self study methodologies?

    Does anyone know of research that has combined Bakhtinian dialogic and self study methodologies? OR of research that has employed a self study approach to explore the practice of infant teachers?

    Heidy Robles

    Hello Bridgette,

    The following link could be useful for your interest. Rupert Wegerif has worked  a lot with dialogic education:


  • Gene Albrigo added an answer in Edaphology:
    Can you propose single predominant soil property influencing the crop performance ?

    Considering the heterogeneous nature of soil , a wide range of soil properties , often inter-related  with each other, influence the performance of different crops . These soil properties comprise of  ; physical , chemical , biological and  genetical in nature . In this background , i submit my following questions to my learned colleagues to express their candid opinions :

    * How does soil genetical properties ( Related to soil geology ) influence crop performance ?

    * Is there specific synergy between biological properties and crop performance ?

    * Which soil properties out of physical , chemical , biological and genetical in nature influence the crop performance the most ?

    * If so , let us propose single most important soil property to dictate the crop performance by and large? 

    Gene Albrigo

    Describing a single most important soil factor is not feasible.  Rather you have to consider the crop and the soil's limiting factors.  To some extent the important factors like pH and nutrient availability can be compensated for by soil or spray amendments.  Soil depth may be important depending on the crop.  Perennial crops usually do better with deeper soils, but can be grown on shallow soils if inputs are frequent and sufficient anchorage is still provided. I think it is better to consider each case for limiting factors.  A crop should not be grown if the limiting factors are major and can not be overcome economically.

  • Oluwafemi Samson Balogun added an answer in Population:
    If I wanted to examine the relationship of two variables, and I made the associative hypothesis. What is the exact formula to test the hypothesis?

    I was researching the relationship (X) and (Y), where this research was the study population because the population is relatively small. Then I make a hypothesis, there is a relationship between (X) and (Y). In this case I want to ask:

    1. What is the exact formula to test the hypothesis?

    2. What is the exact formula to data analysis?

    Oluwafemi Samson Balogun

    Jorge has said it all but another thing you can try is t distribution

  • Laurens Van der Leij added an answer in Resource Economics:
    Are there any published books on Range-land Economics/ Range land resource economics?

    The economic decision-making in the context of range lands/ dry lands is increasingly gaining cognizance among researchers, policy makers as well as development partners. By virtue of being a resource economist, I am interested in knowing much on how economics has been applied to give solutions to the inevitable problems within the rang-elands/ dry lands.  

    Of interest to me are publications (books) specifically dealing with range-land economics. Kindly assist me get such materials. Thank you.

    Kind regards,

    Dennis Olila

    Laurens Van der Leij


    Economy and Ecology of Heathlands, heathland ecology and management

    Author: Editors: W. Herbert Diemont, Wim J.M. Heijman, Henk Siepel & Nigel R. Webb

    be a help to you

    kind regards,


  • Antonio Velasco added an answer in Teaching Chemistry:
    Are there experimental studies about Dynamic testing (Dynamic assessment), applied to the teaching of Chemistry in High school?

    I've been the mentor of a research in this issue, and we would like to get studies about this topic.

    Antonio Velasco

    Dear Marco: I would really like to learn from your research, Could you please send me the paper?  

    Thanks a lot!

  • Josef Punčochář added an answer in Electrical Engineering:
    Who was the the first to investigate the concept of "negative resistor" ?

    So far I have found:

    Author:  Usui
    Journal Journal of the Institution of Electrical Engineers of Japan — 1931, Volume 51, pp. 393-403
    A mathematical paper in which formulaelig are derived, which may be applied to determine the characteristics of oscillators of the negative resistance type. One of the formulaelig may be used to explain the frequency variations of self-excited triode oscillators. The disadvantages of previously publ...

    Josef Punčochář

    Similar research can be done for approximation of filters. See my questions about it.


  • Taha Ibrahim added an answer in Concrete Technologies:
    Are there papers about axially loaded sheet pile wall or piled retaining wall?

    about axially loaded retaining system adjacent excavation

  • Andrea Abarzua added an answer in Exploratory Factor Analysis:
    What does a negative value for factor loading mean?

    I run exploratory factor analysis with oblimin extraction. 2 out of 7 components show a negative factor loadings for all the items. What does it mean? 

    Andrea Abarzua

    Yo could also verify if the item-test correlation of those ítems is zero order or negative. Such analysis is always helpful understanding the nature of the test, beyond the specifics of factorial analyses. Also you conducted a oblimin rotation, so you should take a closer look to that technique to understand your results. 

  • Bernardo Alves Furtado added an answer in Applied Microeconomics:
    Which microeconomic agent-based market models are there?
    Apart from early models of Sugarscape (local market), hash and beans (by Tesfatsion, incomplete), Litghttower (at EURACE project, also incomplete), and "A Generic Framework for a Combined Agent-based Market and Production Model" by Straatman et. al. What other microeconomic models of markets (goods, land and labor) are there? I have seen some of labor, a lot spatially focused, but not a single one that reproduces basic models.

    Note that there are a lot of macroeconomic models, especially of financial markets. That is not what I am searching for. I want a detailed, step-by-step design of consumers, labor, land market that I can build upon.

    Thank you.
    Bernardo Alves Furtado

    Thanks a lot, Professor. I've downloaded that and will examine it carefully.

    However, I was looking (at the time of the question) for the mechanisms behind ABM that were (easily) implemented. That is: how are salaries decided upon? How firms set prices? How is the process of search in the labor Market.

    This first model presented in Portuguese contains these answers for the 3 markets: labor, goods and real estate. I went to the literature to find support for my implementation on the decisions.

    The model is in Portuguese, but the ODD in English is available, as well as the PseudoCode for the markets.

    I promise it in English for next week.

    Thanks again,


    p.s. A recente and valuable reference is

    Agent-based Models of the Economy From Theories to Applications  
    Riccardo Boero, Matteo Morini, Michele Sonnessa, Pietro Terna

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Este texto simula a evolução de economias artificiais no intuito de compreender a relevância tributária de limites administrativos na qualidade de vida de seus habitantes. A modelagem consiste na construção de algoritmo computacional cujo desenho contemple cidadãos, organizados em famílias; firmas e governos que interagem em mercados de bens, de trabalho e imobiliário. O mercado imobiliário permite que as famílias se mudem para domicílios com maior qualidade ou menor preço, quando capitalizam a valorização dos terrenos. O mercado de bens comporta a busca do consumidor em número flexível de firmas, escolhendo por preços e proximidade. O mercado de trabalho é dado por processo de pareamento entre firmas (dada sua localização e salário ofertado) e candidatos, de acordo com sua qualificação. O governo pode se configurar em uma região única, ou com quatro ou sete governos subnacionais distintos, porém conurbados economicamente. O papel do governo é coletar impostos sobre o valor de venda das firmas no seu território e aplica-los na melhoria da qualidade de vida dos habitantes. Dentre as limitações do modelo, ressalte-se a dificuldade de compor ajustes entre processos, classes e agentes de forma dinâmica. Ou seja, balancear e equacionar efeitos diferentes no tempo e no espaço. Além disso, o modelo não conta com um mercado de crédito, dado que a ênfase da pergunta de pesquisa está na relevância tributária dos limites administrativos municipais. A análise dos mercados permite indicar trajetórias de desenvolvimento e mecanismos geradores de dados para cada recorte territorial utilizado. Os resultados sugerem que a configuração dos limites administrativos é relevante para os níveis de qualidade de vida advinda da inversão dos tributos. O recorte com sete regiões é mais dinâmico, com maiores valores de PIB, porém mais desigual e heterogêneo entre as regiões. O recorte com região única é homogeneamente mais pobre. O trabalho busca contribuir como referência teórico-metodológica para descrever, operacionalizar e testar modelos computacionais de análise de finanças públicas, com viés explicitamente espacial e dinâmico. Várias alternativas de expansão do modelo para objetos de pesquisa próximos, inclusive a aplicação a municípios conurbados de regiões metropolitanas brasileiras, são relatadas. Ademais, sob a ótima acadêmica, este trabalho contribui com a literatura existente, especificamente avançando nos modelos computacionais microeconômicos ditos simples e especificando governos locais e relações entre firmas, consumidores e domicílios por distância.
      Affiliation: Institue for Applied Economic Research (IPEA), CNPq, UnB
  • Carol B Griggs added an answer in Climate Variability:
    Where can I get climate variables for the Younger Dryas period (circa 14.000 years BP)?

    In my study I am trying to verify whether there have been climate refugia for a species. Unfortunately, publicly available databases only have data for the Last Glacial Maximum (circa 21kya), the Holocene (circa 6kya) present and future. Considering that the Younger Dryas were a period of forest (vegetation) contraction and this could influence the distribution of my targeted species, I think it would be important to include it in my study. Unfortunately, I can't find climate variables for this period. Can anyone provide any suggestion?

    Thanks in advance!

    Carol B Griggs

    I work with tree rings and have just started a project on a YD site here in New York.  I have also worked on earlier late glacial sites in NY.  I agree with the lack of high resolution records for the YD and the possibility of different conditions around the globe!  So far, with 14C dates, I have the end of the mastodons at around 12,700 cal BP at the older sites, then trees indicating good growth conditions starting at ~12,600, definitely by 12,500 at the YD site.   Perhaps the ice core 18O reflects more the size and proximity of the ice sheet and the route of meltwater drainage?

  • Gerald van der Grijn added an answer in Sugar Beet:
    How can I forecast internal temperature in a sugar beet clamp based on weather forecast & current log of temperature sensors in this clamp?

    We have a 22 sugar beet clamps for a long-term storage. Every clamp monitored with the temperature sensors.

    I need to extrapolate respiration process based on a some extrapolation function. This task has a decision, and we can test it on our storage field.

    But I need to correct the forecast with the weather forecast?

    Does somebody have such experience?

    Maybe you know some articles or researches on the sugar beet clamp thermodynamic?  

    Gerald van der Grijn

    If you have a dataset with temperature observations spanning e.g. 2 years it is relatively straightforward to derive regression equations that describe the relationship of internal sugar beet clamp temperatures with weather forecast model output. This technique is commonly known as MOS.

    If your dataset is shorther I would indeed go for the Kalman filter approach. However, keep in mind that, in addition to historic data, you would need actual temperature measurements as well.

    I am experienced in the above two approaches. Our company would be willing to assist you if needed.

  • Mafizur Rahman asked a question in Bacterial DNA:
    PCR using universal primer .

    Please  help me anyone    I  want to isolate Bacterial DNA of wild mouse  fecal and doing  PCR using  universal primer ..  I did the work  but  still  i did not  get result.   give  me suggestions  What  are the problems  ?  

  • Marcelo Guimarães Silva added an answer in Sport Biomechanics:
    What is the best protocol for measuring muscle stiffness in physically active population and in athletes?

    In his paper Locatelli (1996) states that he used the stiffness test by Carmelo Bosco (1991). However there is no reference to Bosco's article in Locatelli's  article.

    Locatelli 1996, states that the protocol for measuring muscle stiffness consisted of 5 successive vertical jumps on the conductance mat, subjects were keeping their legs almost straight, bouncing on the balls of their feet and using their arms to help.


    Locatelli E. (1996). The importance of anaerobic glycolysis and stiffness in the sprints (60, 100 and 200 metres). New Studies in Athletics: 11:2-3; 121-125.

    Marcelo Guimarães Silva

    I believe that the protocols defined in the research below respond your question, but I think that you should research a protocol that use as material; the force platform and the EMG's system, because I think these are the best biomechanic's tools to your case.

    Acute Effects of Different Warm-Up Protocols on Anaerobic Performance in Teenage Athletes (FAIGENBAUM et al., 2006)

    A comparison of muscle stiffness and musculoarticular stiffness of theknee joint in young athletic males and females (WANG et al., 2015)

    Athletic Footwear, Leg Stiffness, and Running Kinematics (BISHOP et al., 2006)

  • Malik Ahmad added an answer in Actor Network Theory:
    Does anyone know about theorizing situated reflective practice in junior doctors to enhance learning?

    Hi, I am working on theorizing situated reflective practice in junior doctor to enhance learning, i will appreciate if anyone can guide about recent papers and work in health sectors.

    I am building on 'organizing reflection' (Reynolds and Vince 2004) but still not finding some recent developments in the field.

    this place is really full of intellectuals, so i really appreciate any help in this regards.

    Many thanks,


    Malik Ahmad

    Thanks Ingmar, Yes I am getting help from CoM concept to elaborate on social and material aspects by linking it with ANT

    I will share by paper soon. Thank you every one

  • Harry ten Brink added an answer in Climate Change:
    Are there authentic published work confidently pinpointing the sole anthropogenic factors contributing to Climate Change?

    Combined natural and anthropogenic factors (geologically recent phenomenon) govern Climate Change. It is, therefore, of paramount importance to discretely recognize the role of humans in Climate Change and to plan efficient strategy to mitigate it.

    Harry ten Brink


    Worse than an illusion of science is the ilusion of reading someone's entry and then in your response quote the wrong wording?!

  • Christian Wechselberger added an answer in Lyophilization:
    Any experiences to handle peptide (from digested protein) in solution?

    I have to sent some peptide (from digested protein) to abroad, but the problem is we haven't have vacuum concentrator, so we cannot make lyophilized peptide. Can we shipping the peptide in solution form? Do you have any suggest about the buffer and temperature of the solution?

    Christian Wechselberger

    You could try to precipitate your peptides with 5 volumes of cold (-20 C) acetone. See the following protocoll:


    Best regards,


  • Hossein Soleimani added an answer in LaTeX:
    Which nanomaterial increases corrosion resistance of acrylic copolymer latex?

    Apart from sio2 and tio2 and clay Which nanomaterial increases corrosion resistance of acrylic copolymer latex?

    Hossein Soleimani

    ZN IS REACTIVE! Not reported

  • Laurens Van der Leij added an answer in Entomology:
    Is there a safer alternate to chloroform for killing wild adult mosquitoes collected using standard collection methods?

    Most of our entomological  collection methods involves adult mosquito collections and storing them dry in silica-filled tubed for processing in the laboratory. However, recently due to safety concerns, we have been advised to cease the use of chloroform to chloroform-kill the mosquitoes before morphological identification and storage. Are there other safer alternatives to use? Any relevant literature on the subject is greatly appreciated.

    Laurens Van der Leij

    Put them in a plastic or glass jar and expose the mosquitoes to the sun. They will be dead in max 15 minutes.

    Ethyl acetate is usually an ingredient of nail polish remover. A cheap alternative to "pure" ethyl acetate.

  • John T Corthell added an answer in HEK293 Cells:
    Can anyone explain the concept of "poor space clamping"?

    I'm new to the field of electrophysiology and I'm having difficulty understanding the literature. I understand that it is an error making the interpretation of recorded currents impossible. From my experience it makes the I-V relationship look a little ridiculous.

    I'd like to know how does it affect the voltage clamp and how does it affect the current trace? It would also be useful to know how to avoid poor space clamping. I'm working with voltage-gated sodium channels stably expressed in HEK293 cells - not primary neuronal cells.

    Many thanks in advance! Your time is greatly appreciated.

    John T Corthell

    Space clamp refers to how much of the cell is truly under voltage clamp, i.e., am I holding the whole cell at -70 mV or just the soma? Are the dendrites not clamped and still have channels opening and closing? Poor space clamp affects voltage clamp by the fact that you don't really have voltage clamp, you have 'clamped' only one part of the cell; see the link for how it changes the kinetics and amplitudes of the trace that you see when recording data.  I don't have experience with what it looks like under current clamp. 

    In my experience, poor space clamp was best fixed by finding another cell.  Any problems I had with space clamp were due to the size of the cell (larger cells have more significant issues with space clamp) or a bad break-in.   

  • Aimeric Blaud added an answer in T-RFLP:
    What is the proper way to analyse the T-RFLP data?

    Currently, I haveT-RFLP raw data. I have used Mica3 to export all of the genera. I used three enzymes to digest my samples. Could you please give me some suggestion on how to further analyse them? Which software should I use to do which kind of analysis? If possible, could you please give me the examples?

    Thank you very much.

    Aimeric Blaud

    You have to use the comparison file. The aim of T-Align is to align your samples, so before alignemt, your results look like the consensus file. When aligned, you know for each size of T-RFs found between all yours samples, which samples have this size with the corresponding peak area (or height) and when the T-RFs is not present in a sample there is a zero.

    You change any T-RFs below 0.5% into 0. In your case I would try both by changing into 0, and not removing below 0.5% to see how it affect your data.

    Then you normalised your data by diving the value for each T-RFs in each sample by the sum of all the T-RFs in the sample (see file attached).

    When it is done, you have your data that you can use for statistical analysis. So you can square root your data, then construct a similarity matrix using Bray-Curtis and finally peform nMDS or dendrograms coupled with statistical analysis such ANOSIM.

  • Maxime Yochum added an answer in Code Development:
    How can i use the Bat algorithm to tune a PI controller ?

    I intend to use the matlab code developed by Xin-She Yang, attached below to obtain the optimal Ki and Kp.

    + 1 more attachment

    Maxime Yochum

    You may check out this article :


  • Thomas J. Miller added an answer in Stock Assessment:
    Recommended data-limited stock assessment approaches for invertebrate species?

    What are the most practical data-limited approaches used to assess or manage invertebrate stocks such as lobster and conch when catch rates and age/structure are poorly known?



    Thomas J. Miller


    Have you looked at the DLMtool box in R?  It is pretty flexible.

  • Francis Steven Mickus added an answer in Art:
    Do we need any definition of Art?

    I´am wondering if we need any kind of definition of Art. In the last period of time, the Fine Art lack any boundaries, or rather should I say any bounderies that couldn´t be falsified. For example if some artist make sincerely a piece of Art and react on something, and some years later, somebody else make something simmilar but inspired only by succes of the first artist and we recognise him, is the second artist also real artist and maker of Fine Art? So I think, there should be some ground rules, and we couldn´t just agree with everything. What I am trying to say, is that despite the overcome normativity in art there should be some rules.

    Francis Steven Mickus

    Again, there are correlary questions in the initial offering by Mr; Makki which I find interesting in that they ask the question very precisely.

    Are there boundries to art that cannot be falsified? is there a difference between human activity that is not artistic (say creating a jug) and the activity that is artistic (say embellishing that jug) which is the artistic activity and which is not? An ancient Greek would say that there is no difference. The entire discussion we have had makes precisely that distinction.

    Then what is that definition?

    Must art be original? If artist A creates a work, can artist B create a work like artist A's and in so doing still creat a work of art? The answer to that Lies in the examples of Shakespeare's Trolius and Cressida , which is based on Chaucer , which in turn is inspired by the Classics. Racine Wrote Phèdre, based on Seneca's play which was based on Euripides' play Hippolytes. The examples never end. but aren't we always discussing distinct works in each case?

    Neither originality, nor beauty are indicators in the case of the jug or in the case of the plays. However specific creation is an indicator in every case.

    Are we not in fact approaching a definition of what art is?

  • Elena Panagiotou asked a question in Transgenic Animals:
    Has anyone had any experience with using FlAsH-EDT2 or ReAsH-EDT2 in transgenic animal models in vivo?

    Has anyone had any experience with using FlAsH-EDT2 or ReAsH-EDT2 in transgenic animal models in vivo?

  • Li Xiaoqiang asked a question in Amino Acid Sequence:
    How to know what activities does a protein have?

    If I know a protein's amino acid sequence, how can I know what activities this protein may have?