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  • Bindesh Kumawat asked a question in Electrical Power Systems:
    May someone tell that where we are using cloud computing in electrical power system?

    i need information where cloud is applied for grids

  • Yutaro Hori added an answer in Tamoxifen:
    Any suggestions on CreERT2 activity in the absence of Tamox?

    Hi, I am currently assessing recombinase activity of my CreERT2 construct.

    I transfected mouse ES cells with CAG promoter-loxP-CAT gene-pA signal-loxP-EGFP plasmid and SV40 promoter-CreERT2-pA-hEF1a promoter-RFP-pA and then saw what concentration of 4-OH tamoxifen was required for the recombinase activity of CreERT2.

    Surprisingly, I found that the In the absence of 4-OHT, most of the transfected cells were EGFP positive.

    I confirmed the sequence of CreERT2 of my plasmid and that without CreERT2 plasmid no cells were EGFP positive.

    Have anyone experienced anything like this before? 

    I am wondering if the too high expression level of CreERT2 is the problem.


    Yutaro Hori · The University of Tokyo

    I assumed that CreER could control recombinase activity more tightly. After reading your reply, I have found several papers dealing with leakiness of CreER.

    I will try a different CreER construct following your advice.


  • Harmandeep Sekhon asked a question in Nitric Oxide:
    For nitric oxide level determination in human serum is it necessary to reduce the sample with reductase prior to griess reaction?

    I have done this without using reductase as i have read it somewhere.But i have this confusion.

  • Anil Mali asked a question in Bromides:
    Does anyone know how to shift the crystallization temperature of lithium bromide by adding any other salt?

    how can we elevate the crystallization temperature of lithium bromide, if anyone know the method please share it on anilmali206@gmail.com

  • Anoop Kumar Srivastava added an answer in Heavy Metal Accumulation:
    How does microbial diversity of contaminated soil differ from normal agricultural soil?

    Microbial abundance of soil is normally  considered  synonymous to higher bio-availability of nutrients , and hence soils are biologically more responsive to any management input(s). The soil microbial diversity in a given soil is claimed to undergo transformation in response to metabolic requirement of any crop being grown on a specific soil. In this background , I call upon my esteemed colleagues to throw some valuable comments  on the following issues:

    # How does a stable microbial diversity  in a given soil undergo reorientation in response to heavy metal accumulation/contamination/.

    # Do we expect a definite change in structural and functional composition of microbial diversity in the light of contaminated soil vis-a-vis uncontaminated/normal soil ?.

    # Which group of microbes is  considered more sensitive ( Prevalence of one species over other ) to such disturbances in soil microbial environment?.

    # What kind of implications of contaminants  , do you anticipate in the context of bioavailability  of nutrients in soil ?.

    Anoop Kumar Srivastava · Central Citrus Research Institute ( Formerly National Research Centre for Citrus )

    The discussion on the subject is now  growing  very interesting . Friends , let me float another  important issue . For example, Huanglongbing ( Greening disease ) in citrus  brings any change in soil microbial communities and their functional profiles ( There are some literature on this issue). I  still remember , there is  a preponderance of Pseudomonas over Bacillus species, reported  in apple infected with apple scab . What kind of physiological or biochemical messages are sent by the shoot tissues to the underground roots  and  vice-versa , in turn , communicated to the microbial pool of plant rhizosphere ?. This part  remains to be addressed more aggressively.

  • Shehan Perera asked a question in Phonons:
    Is it possible to phonon-photon interaction in solids?

    phonon-photon interaction ( collision or heat transfer in between photons and phonons) 

  • Fabienne Merola asked a question in EGFR:
    Has anyone tried tagging EGFR with a GFP on its Nter domain ?

    Is it possible to tag EGFR with a GFP on its Nter extracellular domain ?

    I cannot find any report of such construct in the literature.

    Has anyone tried, and did it impair ligand recognition ?

    Thanks in advance for any hint,

  • Martina Gaisch added an answer in Human Centered Computing:
    Has anyone conducted research on intercultural human-centered computing or user design interface?

    How important do you consider an intercultural lens on usability engineering? Where do you see its potential and also its limitations and why?

    Martina Gaisch · Fachhochschule Oberösterreich

     dear Ashok, 

    thanks for this useful hint. I have just found some of his work here at RG. 

  • Vladimir A. Kulchitsky added an answer in Social Services:
    How can I tackle the social services in European countries?

    Social services providers have a distinct social objective. By delivering essential services social services are crucial for the well-being of citizens and for the european social and territorial cohesion.

    But so far, with the partial exception of "Mapping of public services" projects, no studies heve been made to analyse this sectors at European level. 

    How to go further than the outcomes presented in the "Mapping of public services?

    Vladimir A. Kulchitsky · National Academy of Sciences of Belarus

    Dear Helena! You promptly raised the actual topic. Let us look at just one aspect of this problem. The problem of refugees and social services in developed countries.
    1. I think that everybody understands that the problem arose because the problem is a result of many factors.
    2. Developed countries have in the past (distant or near) colonized countries on different continents. Formed developed and undeveloped countries. In underdeveloped countries, is particularly acute there are social problems associated with the division of scarce income between "rich" and the "poor". Intensifies the struggle for power. In this struggle unhelpful role played by the developed countries that are arming both opponents. From war suffering citizens. To save lives and the future for their children, citizens of underdeveloped countries "run" from the home country in the developed countries. There are refugees.
    3. Thus, increased uncontrolled emigration. Special sizes such emigration gains in areas of the world where armed super-modern weapons people are sowing death and destruction on the type of infestation, which destroys all the fertile crops. By the way, note the fighters of the Islamic State in different ways get weapons manufactured in developed countries. In developed countries migrate to citizens of those countries, which use modern weapons.
    4. Now take into account the citizens of developed countries. These citizens of honest labor, and create the future of their country. As always before, the ordinary citizens selflessly trying to help refugees from countries affected by wars. But, those who are arming the killers, passivity in providing charity.

  • Henri A Ménard added an answer in Rheumatoid Arthritis:
    Does anyone have a patient with AIDS associated with rheumatoid arthritis?

    Does anyone have a patient with AIDS associated with rheumatoid arthritis?

    Henri A Ménard · McGill University

    Most of what I wrote is referenced in  editorials I wrote for J Rheum 2009 and 2015 (See attached files)

    Thanks and best.  


  • Sushil Kumar Himanshu asked a question in Water Erosion:
    Can anyone please help me to simulate water quality parameters for an Agriculture watershed using WEPP model?

    I am trying to simulate water quality parameters for an Agriculture watershed (Area approx 5000 km2). Is there any module to simulate the same using WEPP (Water Erosion Prediction Project) model.

  • Anshary Maruzy added an answer in Botany:
    What is this plant?

    this is climber.

    leaves single, lenceolate and alternate.

  • Muayyad Ahmad added an answer in Mplus:
    What does it mean we control for another variable in multiple regression?

    In multiple regression on SPSS or Mplus I have two predictors

    1. Years in education

    2. Years of working experience

    Based on those two I am predicting annual income. 

    I have two coefficients for predictors (both significant). So I report that one of those two is a significant predictor of annual income while controlling for the other predictor. But what exactly does this mean - "CONTROLLING FOR".

    Thank you for answers

    Muayyad Ahmad · University of Jordan


    when there is an extraneous variable we want to exclude its effect, we do control on this variable. unles you know this variable and dealth with it as covairate, you dont need to write the statement in your question.

    usually we do hierrarchical regression to control for the covariate.


  • Elizabeth Yanez added an answer in Crop:
    Could anyone recomend an article to me about the potential advantages and risks of generating transgenics crops?

    Some articles mention the limitation to predic the possible effects on the enviroment of transgenic crops and express the concerns about gene flow. However other articles mention that transgenic crops can help to reduce the use of pesticides. What scientific support is there for these contrasting viewpoints? Please if possible provide to me the articles because i do not have free access to some of them 

    Elizabeth Yanez ·

     Dear Jaime

    Thank you for your message. Could you please send me the articles Precautionary Principle and Ecological Hazards of Genetically Modified Organisms?

    Thanks a lot for your help


  • Charles Berg added an answer in Plagiarism:
    What percentage (maximum) of plagiarism is generally allowed in a review paper?

    I want know about what percentage of plagiarism is allowed to make a review paper acceptable in journals.

    Charles Berg · University of Luxembourg

    There is a kind of disguised plagiarism. You give a reference. It seems to be of marginal importance, but actually you copy or paraphrase the main idea of the source and make it your own. You pretend to have found something which comes from another person's thinking, work etc. The ideas coming from others are the essential part of the contribution published under your name. The core criteria is not a lacking reference, but stealing the ideas from other people.

  • Stelios Ioannou added an answer in Circuits:
    Why does the current go high in a Series-Series Inductive Power Transfer (IPT) circuit when applying just a few volts?

    I am operating series series Inductive power transfer (IPT) circuit with loaded quality factor of secondary 3.5. The current goes high even with very low voltage. Need suggestion

    Stelios Ioannou · European University of Cyprus

    I agree with Kunwar that circuit parameters affect the performance and should be considered during the design phase of any project.

    Your problem is a typical RLC circuit problem and yes by increasing the load resistance might limit the spike amplitude but at the same time I think that it will also decrease your circuits efficiency. So, you might also consider adding a shunt Metal Oxide Varistor (MOV) to limit the spike and not affecting the overall load impedance. 

  • H.Kemal Şenyilmaz added an answer in ANSYS Workbench:
    Do you know which code I should write in Ansys Workbench Explicit Dynamics module for changing element type to Shell163?


    I want to mesh a solid body with shell163 element for explicit analysis in Ansys Workbench15. 

    Do you now how I use Shell163 in Ansys Workbench Explicit Dynamics?

    Do you know which code I should write in Ansys Workbench Explicit Dynamics module for changing element type to Shell163?

    Which codes I must write in Command line?

    Thank you.

    H.Kemal Şenyilmaz · Gazi University

    Thank you, Mr.Aresh.

  • Anshary Maruzy added an answer in Herbarium:
    Can we replace herbarium samples with scanned samples of plants?

      In your opinion, what are advantages/ defects of this replacement? 

  • Stephen Cheung added an answer in Emotional Psychology:
    Can anyone suggest some good recent articles/meta-analysis on disaster, trauma children and art therapy as an intervention?

    I am applying for my phd and my area of interest is disaster(both natural and man-made specifically terrorism) trauma, children and art therapy as an intervention. I am from pakistan and in our country war and terrorism has been increasing. We also face natural disaster like flood and earthquake. Children are the victims but there is no such intervention measures taken for emotional and psychological rehabilitation of children nor we have any trained professionals in this area. since i have been trained in art therapy therefore i want to work on art therapy as an intervention for theses children. I am working on my phd proposal and need some evidence on art therapy and the gaps in it. what is the efficacy of art therapy for children going through trauma after a disaster both natural and man-made?

    Stephen Cheung · Azusa Pacific University

    Dear Ayesha,

    These articles may interest you:

    • Post-Disaster Group Art Therapy Treatment for Children by Caitlin Frances Murphy.
    • School-Based Intervention for the Treatment of Tsunami-Related Distress in Children: A Quasi-Randomized Controlled Trial by R. Berger R & M. Gelkopf. 
    • A review of research and methods used to establish art therapy
      as an effective treatment method for traumatized children by Leslie G. Eaton, Kimberly L. Doherty,  & Rebekah M. Widrick.

    Best wishes,


  • Diana Patricia Lozano Zafra added an answer in Glacial Geomorphology:
    How can I find the relationship between glacial geomorphology and groundwater, using remote sensing and terrain analysis?

    Right now I am working on a project with the Bogota Water Company. This company is in charge of water supply for the entire city of Bogotá. The water is taken from Chuza River basin, that is located in Chingaza's paramo. Paramo ecosystems are intertropical montane ecosistems located between 3200 meters above sea level and 4000 meters above sea level, with temperatures ranging between 2C and 17C, the mean annual temperature is 10C. In Colombia, all paramos are located on old glacial landscapes .

    The project is about understanding what could happen with the water supply under global warming conditions.

    From some fieldwork observations as well as aerial photographs interpretation, I could infer that glacial deposits offer the mot suitable geoforms for water catchment, and water infiltration. Glacial deposits have a high rugosity which is evidenced by the presence of a lot of depressions that concentrates water in small and swallow lakes similar to wetlands. I would like to produce a model, that gives me the water catchment susceptibility and water infiltration susceptibility in terms of geomorphology.

    In order to solve this issue, I would like to know if anyone can help me with articles, techniques, methodologies regarding the evolution of glacial and periglacial geoforms under global warming, and regarding the relationship between glacial geoforms and water catchment, as well as glacial geoforms and water infiltration.

    I would appreciate any information,

    Kind Regards,

    Diana Lozano

    Diana Patricia Lozano Zafra · Universiteit Twente

    Thank you so much, it looks really interesting I will read it and let you know! :)

  • Wolfgang H. Muss added an answer in Paraffin:
    Any advice on methods for double embedding small tissue (agar and paraffin)?

    I am trying to double-embed very small tissue pieces for histology and am having some trouble. The tissue is tiny and in order to orient it properly (and not lose it) I have been embedding it in agar (1 or 2% low melting point) and then dehydrating as usual. My problem is that the paraffin is not infiltrating the agar and I get a soft blob in the paraffin block that is not stable enough to cut. I have tried expanding the length of time in dehydration and clearing, but that hasn't worked so far. I also refreshed my ethanol so I am sure of the concentrations. I only expanded the time in each ethanol solution by about ten minutes so far. My procedure looked as follows:

    Tissues were fixed in formalin. After three (sometimes more) days, tissues were embedded in agar and then placed in formalin overnight.

    Tissues then underwent dehydration:

    • 70% EtOH 30 minutes
    • 70% EtOH 30 minutes
    • 80% EtOH 30 minutes
    • 95% EtOH 30 minutes
    • 95% EtOH 45 minutes
    • 100% EtOH 45 minutes
    • histochoice clearing agent 30 minutes
    • histochoice clearing agent 40 minutes
    • histochoice clearing agent 40 minutes
    • paraffin 30 minutes
    • paraffin 40 minutes
    • paraffin 45 minutes
    • embed in paraffin blocks immediately

    The agar blocks are still soft after this procedure. The protocols I have read mostly state to "proceed with dehydration as usual" after embedding in agar, but that is not working for me at all. Help would be greatly appreciated!

    Wolfgang H. Muss · Paracelsus Medical University Salzburg

    THIS post has been edited 3 minutes past first posting (see below)

    @Maria Frances Bukelo:  Dear Maria, unfortunately the URL you have given above is unfunctional and ends up with notifying:  ERROR, PAGE COULD NOT BE FOUND.

    Since the article:
    <Improvised double-embedding technique of minute biopsies: A mega boon to histopathology laboratory > p. 12
    Lokendra Yadav, Sarega Thomas, Usha Kini
    DOI:10.4103/0377-4929.151156 PMID:25673584

    is not accessible for free (Purchase for US$ 20.- or subscribe or Login),  at least the abstract can be found (ABSTRACT) visiting:


    It would be nice (if you are allowed to do so) either to attach the pdf to your kind reply or to send a pdf-copy to interested colleagues like me via RG-Messaging.  Thank you in advance, best wishes and regards, Wolfgang

    Maria, apologize...I just found out that (at least for me) the html-text version was open access and readable.  Apologize for the inconveniences you might have had with my post.

  • Naeem Fiaz added an answer in Sugarcane:
    Identification of sugarcane varieties?
    I am preparing a comprehensive book for sugarcane varieties identification. Most of our local farmers and sugarcane procurement staff of sugar mill get confused. Can anybody share experience, or suggest literature?
    Naeem Fiaz · Ayub Agricultural Research Institute

     Thanks dears...

  • Mary Luka-Anzah Paymwa Kagoro added an answer in 1H-NMR:
    What is the easiest way to obtain NMR data on a compound using "Spectral Database for Organic Compounds SDBS"?

    Is it possible to just type in the CAS number and name of a compound to see NMR data of a compound using "Spectral Database for Organic Compounds SDBS" . I have used the database successfully before but at times it can  become really frustrating with the

    "Search Results 0 Hit.
    Return to Search Page"

    How do you get your result?

    Mary Luka-Anzah Paymwa Kagoro · University of Jos

    Hello John,

    I agree with Markus  suggestions.  You use sigmaaldrich and reaxxys for compounds with published data but if a new compound then you won't  get any information there. But I also heard you could use simulation to generate nmr data n compare with your actual data.

    I hope this is helpful 


  • Zafar Husain added an answer in Marketing Research:
    What are the recent trends in Strategic Management or Strategic Marketing Management Research?

    I am interested in, to find out recent trends in Strategic Management or Strategic Marketing Management Research for my PhD research. Your valuable feedback will be highly appreciated.

    Zafar Husain · Al Ain University of Science and Technology

    Blue Ocean Strategies is still a highly unexplored area in strategic innovation management.

  • Martin Schulz added an answer in Analytical Philosophy:
    Are there infinitely many possible sentences in a natural language?
    Most authors seem to think so. Frege, one of the few mathematicians who worked on that problem spoke of “unpredictably many” (or uncalculably many; “unabsehbar viele”) - not an infinite number of them. (Frege, Logische Untersuchungen, 3. Teil Gedankengefüge, 1993, p.72 ff (German) /see also Fodor/Lepore „Holism“ 1992,p 242). N.B. „uncalulably many“ is not an NP-Problem in this context.
    I could not find a proof that there are infinitely many sentences with e.g. 30 words, no matter in what natural language. The arguments of Chomsky and Pinker are about the understanding of understandable sentences, not about sentences containing, say, 100,000 words.

    Here is a reformulation of the question: how can we get infinitely many combinations out of a finite number of elements (e.g. English with approximately 5 mil words) containing up to 30 elements, including ungrammatical combinations? We can’t. In order to get more combinations we would have to extend the chains. But even with sentences of 100,000 words there would not be infinitely many of them.

    One simple solution is: “Of course there are infinitely many sentences of the form “This and that is that”, we just have to insert numbers!” But that is not what I mean and it is not what anyone means who is concerned with that problem. Moreover: 1st we would then get an infinite vocabulary – 2nd all these sentences would be comprehensible by the application of one single rule. (Pace Kripke’s Wittgenstein).

    How about propositions instead of sentences? E.g. we might utter “This is not the same as that” pointing to different objects while repeating the sentence. The first problem is that we get many propositions but we still have only one sentence. The second problem is that the propositions are not countable. Third problem: there must be a difference that makes a difference. The objects we want to point to must be discernible. And with a countable number of discernible objects we will only get a finite number of utterances.
    So even for 7 billion people the pointing to discernible objects will lead to a still finite number of possible utterances.

    Some authors compare the number of possible sentences with the number of possible chess games or possible molecules. I don’t know much about these items but it seems to me that for chess and molecules there will be problems comparable to those I mentioned above. Games that get longer and longer, molecules with more and more atoms. Does anyone have another idea?
    Martin Schulz · Folkwang Universität der Künste

    Dear Marvin,

    My example was only a joke! I did not literally mean that 

    Mom has the attribute of "andness".

    It was only an example to show the absurdity. 

  • Dharmesh Parmar asked a question in Freezing:
    How to section a soft tissue stored at -80 degree Centigrade ?

    I want to analyze a tissue using mass spectrometry. I have a tissue which I want to section into smaller pieces. The tissue has been stored in -80 degree C after snap freezing. Is there any recommended procedure to section it at around storage temperature? or is it okay to section it after thawing it to 4 degree c? what are the implications if it is sectioned at 4 degree C conditions after being thawed?

  • Farid Alisafaei added an answer in Static Analysis:
    How to define RHS in UEL for a static analysis?

    Hi every one!

    I'm working on developing a shell element to be implemented in ABAQUS through UEL.

    It's going through a static analysis. and as you may know for static analysis, ABAQUS just needs AMATRX and RHS to be defined via UEL. It must be mentioned that the stiffness matrix is changing at each time increment. The force that has been applied, is a concentrated force and a function of time.

    I've defined the RHS as:


    where [K] is the stiffness (AMATRX) matrix and {u} is the displacement vector at each time increment.

    Since I have some difficulties in getting the expected answer, I'm not sure about correctness of this RHS (I've checked B.C., stiffness matrix and etc. and all of them are correct for sure).

    I would appreciate if you could help me with defining this RHS.

    Best Regards,

    Farid Alisafaei · University of Wyoming

    Hello Ashkan,

    The right hand side vector RHS=-[K]*{U} is particularly correct only when you have a linear elastic problem.

    In fact  RHS=-[K]*{U} is the simplified form of the residual vector for the linear elastic case. As your stiffness matrix changes at each increment, I think your problem is a nonlinear one.

    For example, for a nonlinear plasticity problem (with small strain/deformation), RHS=-[B]T*{Stress}. For a linear elastic case {Stress}=[C]{Strain}=[C][B]{U}, one can see that RHS=-[B]T[C][B]{U}

    You may want to have a look at the following books for the residual force vector:

    "finite elements in plasticity theory and practice" by D. R. J. Owen, Ernest Hinton

    "Computational Methods for Plasticity" by  E. A. de Souza Neto, D. Peric, D. R. J. Owen

    "Finite Element Procedures" by K.J. Bathe

    Hope it helps,

    Best regards,

  • Ketil Winther Pedersen added an answer in Immunoprecipitation:
    How might one overcome heavy chain problem during western blot using LI-COR followed by immunoprecipitation?

    Some researchers suggested to use Glycine buffer for soft elution instead of SDS, while some are saying it is not working well to avoid the heavy chain band at around 55 KDa. Some are also suggesting to use different host specific anbodies.

    Is there any suggest who has experience working with LI-COR system? 

    Ketil Winther Pedersen · ThermoFischer Scientific,

    Hi, here is a few more general thoughts around IP and troubleshooting.

    Low yield:

    • Sample could have been degraded by proteases. Add additional protease inhibitors in lysis and wash buffers. Keep sample and buffer cold at all times. 
    • Ab conc too low. Increase concentration of precipitating antibody. If using the solid support such as Dynabeads - titration of capture Ab bound to Dynabeads is recommended for each new prim Ab.
    • Capture Ab did not bind to Protein A/Protein G. Check the affinity and switch. Other alternative is to couple the capture Ab covalently to the Dynabeads M-280 Tosylactivated. 

    Non-specific binding:

    • entrapment of impurities if using porous supports for capture. This can be by-passed by using a solid support with no internal volume. Increased incubation time will also add to more background so the noise in the system increases. Reduced incubation time is therefore beneficial. However, that requires rapid binding kinetics (Dynabeads protein G). This will also reduce Ab consumption (main driver for cost/IP).
    • pre-clearing is often used to reduce background but can be eliminated by using a solid support. Repeat the pre-clearing procedure several times before doing Immunoprecipitation. 
    • Increase the washing time after immunoprecipitation. As for the washing of blots – include many wash steps after capture and with larger volumes can reduce non-specific binding
    • Increase the stringency of the washes (buffer containing a higher concentration of detergent or salt). 

    IP - Direct method - advantages
    Time savings, fewer steps and is easier to optimize than the indirect procedure
    Lower background, additional steps increase the chance of non-specific signal
    Increased specificity, since the direct method eliminates potential cross-reactivity associated with the secondary antibody

    Indirect method - advantages

    • Flexibility
    • Sensitivity

    Kind regards


  • Swapan Ghosh asked a question in Secondary Metabolites:
    How to extract secondary metabolites produced from actinomyctes cultured by SSF?

    Secondary metabolite extraction from solid substrate cultured actinomyctes..