Q&A

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

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  • Rozita Nasiri asked a question in Histopaque:
    How to separate RBC, WBC and platelet from fresh human blood using histopaque 1077?

    Any protocol will be appreciated. 

  • Harsimran Singh asked a question in Containers:
    Glyphodes split : How many genera ?

    Glyphodes sensu Hampson 1896 contained many present genera such as Glyphodes itself, Palpita, Parotis, Arthroschista, Tangla, Sistyrophora and Cydalima. Can any one please tell how were and why these were split ?

    Thanks in advance.

  • Prakash Chandra added an answer in mRNA:
    After giving stress to bacterial culture, how can I maintain the bacterial RNA integrity so that its mRNA profile does not change?

    I want to compare the transcriptional profile of few genes of treated verses untreated bacterial culture.

    Prakash Chandra · National Dairy Research Institute

    if you want to compare treated and untreated ( as Amit  explained )....go with Amit.. 

    All The Best

  • Sudhirkumar Munishwar added an answer in Rare Earths:
    Can someone explain how to calculate the Judd-Ofelt parameters?

    I am a PhD student from VNIT, Nagpur and I am working on rare earth containing glasses. I want suggestions for the calculation of Judd-Ofelt  parameters.

    Sudhirkumar Munishwar · Visvesvaraya National Institute of Technology

    Thank you R. Morea and Mohammad

  • Emad F. AL-Shareefi added an answer in Distribution:
    What Laplace distribution applications?

    what Laplace distribution application

    Emad F. AL-Shareefi · Southern Technical University

    استاذ محمد السلام علسكم ورحمة الله وبركاته

    سؤالي هو ماهي اهم تطبيقات توزيع لابلاس العملية

    يعني اريد مثال بالواقع العملي ولك كل الحب

  • Abdul Ghafar Wattoo added an answer in Band Gap:
    How to find the Band gap energy of an Oxide Semiconductor from Photoluminescence spectra?

    1.    Is it possible to find that whether the material is Direct or Indirect bandgap semiconductor from PL spectra?

    2.   What other information, we can get from PL spectra?

    THANKS

    Abdul Ghafar Wattoo · Ningbo Institute of Materials Technology and Engineering, University of Chinese Academy of Sciences, China

    Thanks

    Amit Nahor & Puspendu Barik for you kind suggestions.

  • Charles Francis added an answer in Physics:
    Is time quantized?
    Each time a new class of lasers was allowed to produce shorter light pulses, people were wondering whether a time quantization would be observed. The smallest possible quantization is Planck's time 10^-44 s. Some nuclear resonances have been reported having an energy width suggesting a Fourier transform limited duration of 10¨-26s.
    Charles Francis · Jesus College, Cambridge

    Jurg,

    I am delighted that instead of deploring the level of discussion, you have elected to raise it.

    Of course, existence in mathematics is very different from ontic existence, since it means only logical consistency. Non-existence may be more important to questions of ontology. If something is logically inconsistent I think it fair to say that it cannot have ontic existence. This is not just a negative approach. If we can eliminate that which is not, we may be some way towards identifying that which is. I would maintain that identifying what is, is a physical question, not just a philosophical one. Otherwise one is in danger of reducing physics to the methodology of astrology, carrying out meaningless algorithms to produce predictions.

    Bohr, btw, was insistent on complementarity, which ascribed some ontic property to the wave function. Heisenberg perhaps did not entirely agree, but he was not prepared to directly contradict his mentor. This really places complementarity firmly as part of the Copenhagen interpretation. It is an idea which really does not make a lot of sense, and which has confused generations of students. The idea that the wave function is a mathematical tool is much more the stuff of the Dirac-von Neumann interpretation, which Bub calls the orthodox interpretation, which he distinguishes from the Copenhagen interpretation because complementarity is absent.

    Goldstein is a Bohmian. One can say much more about Bohmian mechanics. It is not consistent. It tries to destroy conjugacy between position and momentum and at the same time claims to retain the uncertainty relation. It is refuted by von Neumann's theorem. Bohm did not refute von Neumann's theorem. He simply ignored it, because he did not understand it. Bell also was very critical of von Neumann, but his critique was no more correct than Dingle's criticism of Einstein, and displayed an alarming lack of understanding of quantum theory, even describing a trivial a result using the linearity of operators on Hilbert space as “the arbitrary assumption of a particular (and impossible) relation between the results of incompatible measurements”.

    I agree that there is not much point in discussing that kind of ontological approach. What is required is not discussion, but clear mathematical argument. We should be able to state that the Bohmian approach has no place in discussions on ontology not as a matter of being malicious, or as a matter of philosophical opinion, but as a matter of proven mathematical fact. It is inconsistent and therefore does not "exist".

    What we have instead is a treatise by von Neumann, which is correct but almost unreadable, and arguments in quantum logic which are so abstract that they are not approachable by normal physicists. Eighty years after that treatise was written, and with the benefit of a number of useful theorems and clarifications which come since, I still cannot find a clear pedagogical account explaining why the mathematics of quantum mechanics correctly applies to physics.

    And yet, just as the Lorentz transform is the mathematics of relativity of motion, it can be seen that qm is just the mathematics of relativity of position in a non-determinist universe. I think that is physics, not philosophy.

    Rather than tell students to avoid confusion by not thinking about it, I think we should be seeking to present this in a way that students can follow and understand.

  • Nicholas Syn added an answer in Comparative Genomics:
    Where to get a list of genes which are expressed (transcribed) in a specific organ or tissue?

    Hi! I would like to get a list of genes which are expressed in normal gastrointestinal tissues only. I am thinking along the lines of using public repositories of transcription datasets (eg. GEO, TCGA etc) to this end.

    But this is just my general idea, and have no clue as to the details of this procedure. 

    The simplest way to obtain this list of genes will be much appreciated. Thanks in advance!

    Nicholas Syn · National University Cancer Institute

    Dear Fayez,

    Those NCBI links seem a little complicated to use (at least compared to the other suggested platforms) - might you be able to share more details with regards to how it can be used to derive a list of genes expressed in gastrointestinal tissue only? Thanks!

    Nick

  • Narayan Sharma Rimal asked a question in Economy:
    Is location quotient technique useful in determining the regions share on crop production or production economics?

    Location Quotient (LQ) is a technique that mathematically indexes a region's economy to a larger reference economy and has been widely used by researcher in economic geography and regional economies since 1940s.

    As per available literature it is quoted as an effective way of describing the structure of a regional economy. This technique describes a region's industry mix and determines whether or not a region has its fair share of each industry.

    However, another concept of LQ is that of Export. In the context, export are goods/services which are produced in a region and consumed outside the region.

    Thus, my query is related to the use of LQ technique in determining whether or not a region (In the case of regional diversity in Nepal) has its fair share on crops (Cereals and Pulses) it produce so that they may export if produced in large and import the ones they do not produce much.

  • Bhaskarjyoti Bodo asked a question in Nanoparticles:
    Why green emission takes place from co-doped ZnS nanoparticles ?

    when Mn and Mg are co-doped in ZnS as host matrix, there is green emission observed in PL spectra. 

  • Faegheh Etminani added an answer in Phaseolus:
    Can anyone tell me what is this exactly plant? Phaseolus vulgaris seed, I can not identify this. please send the pic if it is possible?

    please let me know

    Faegheh Etminani · University of Kurdistan

    Hi dear Bahar

    you can find in attached file.

  • Peter Eyerer added an answer in Higher Education:
    What are some good examples for developing team work skills among higher education students?

    I think most times we take it for granted that our students (both undergraduate and graduate levels) have acquired group skills along their educational journey in assigning group work. But, surprisingly, many students experience challenges in completing group projects, which signal a need for developing team-work skills before group work commences. Can you recommend or suggest some workable exercises for developing team work skills among students? 

    Many thanks,

    Debra

    Peter Eyerer · Fraunhofer Institute for Chemical Technology ICT

    Dear Debra,

    we developed at Universities of Stuttgart, Karlsruhe, Furtwangen, San Salbador Brazil the teaching model TheoPrax since 20 years. Team work beside project work on industrial items beginning with 1 st semester is one main feature. If interested you find a lot of publications at reseach gate concerning TheoPrax. We accompany the fundamental project work continually with moduls in project management and there in the moduls for team building, conflict management, communication, swot analysis, aso.

    Best regards

    Peter

  • Miranda Yeoh added an answer in Lifestyle:
    Definition of fatigue/ tiredness in human being? what are the cause and its remedy (without medical interventions)?

    Tiredness/ fatigue or fatigue is a common problem. Often, it is not a medical issue but one that can be reversed by a change of lifestyle.

    Miranda Yeoh · Selangor Matriculation College, Malaysia (Kolej Matrikulasi Selangor)

    FATIGUE IS DUE TO EXCESS PHYSICAL AND MENTAL WORK .  Then we lack good rest, sleep, even nutritious food because work takes up such a lot of time.

    After a while, we come to realize our limitations and catch up on rest and family interaction.  It's people that make our lives meaningful, although work is important.  Have a look at this link.

  • Carole Rushton added an answer in Positive Psychology:
    Can you help me with my mixed-methods research dilemma ?

    I am beginning a research project where I conduct 3 to 4 individual interviews (30minutes) with older subjects in nursing homes suffering from depression. In line with positive psychology, we will be discussing difficult moments/periods in their past and exploring the positive qualities/ressources/traits that enabled them to get over these difficult periods. The hypothesis is that these sessions will lower depression and increase positive affect. The scales to measure this are the CES-D depression scale, the Positive and Negative Affect Schedule and Diener's Satisfaction with Life scale. Measures will be taken pre and post intervention and then at 7 weeks to see how well the results were sustained.

    One problem I have is that I suspect that because they are depressed they will have difficulties identifying the positive qualities they had that enabled them to get over the difficulty. I want to avoid orienting the discussions or being the one to point out the qualities they demonstrated : ideally I should only guide them to see these aspects themselves. Does anyone have a recommendation for a good practical qualitative research methods guide that could help me with this aspect of the interviewing ?

    Problem 2 : what do you think of the scales I've chosen ? The goal being to pinpoint that it is the effects of the intervention (i.e. identification of positive traits in past situations of adversity) that lowers depression and increases positive affect.

    Problem 3 : I recognize the biais that the interviews and the rapport created between myself and the participants in this therapeutic context could in and of itself be the factor that lowers depression and raises positive effect. I do not see how to distinguish in the results the effects of the intervention and the therapeutic relationship. Does it seem feasible in a thesis research project to simply identify this biais ?

    I truly would appreciate your help with this. Unfortunately my thesis professor has not been able to give me enough guidance with this dilemma. Any recommendations are welcome !

    Thanks in advance

    Jones-Nimes

    Carole Rushton · Griffith University

    Hi Holly,

    Oh dear! I only speak 'film French' so used Google translate! Not sure doing a PhD improves anyone's life much let alone transcribing!

    Best of luck, Holly

  • Anshul Faye added an answer in Abaqus:
    Which nodes in a FE mesh are connected?

    Is it possible to easily gest the information (e.g in a rpt file) which nodes in a hexahedron mesh generated by Abaqus are connetcted by a linear segment (which elements are the both ends of one linear segment)?

    The mesh elements are hexahedron (8-node linear brick).

    Anshul Faye · Indian Institute of Technology Kanpur

    Hi,

    Nodes in the elements are always in a particular order. Attached image shows the order of nodes in a linear brick element in ABAQUS. If you check the connectivity of an element either in *.INP file or using query option in ABAQUS CAE, you will get all the nodes in the element. These node number follow the order given in image. 
    Hope this helps.

  • Thomas Myles Ashhurst added an answer in Intracellular Cytokine Staining:
    Is it possible to successfully conduct intracellular cytokine staining and proliferation with analysis via flow cytometry?

    I am developing a flow cytometric assay to assess ICS (with CD3 and CD4 staining) post ex-vivo PBMC stimulation with a killed virus. We would ideally also like to assess if the CD4 cells are proliferating. I am finding conflicting (or even lack of sufficient) information regarding if it is possible to conduct both ICS and proliferation on the same cells. Some information says it is not possible for nuclear stains as the strength of permeabilization needed will 'release' the cytokines, so there will not be sufficient ICS. Whereas other proliferation markers seem to stain proteins within the cell, can these interfere with ICS?

    Has anyone done this successfully?

    Thank you in advance for any help/advice!

    Tatjana

    Thomas Myles Ashhurst · University of Sydney

    I think Ki67 wouldn't be all that useful anyway as it tells you that cells are in cycle, but not what part of the cycle. Something like CFSE and one of the CellTrace options would be good, as you can actually see the number divisions that your cells have completed.

    To do this you would label your cells with the CellTrace (and wash it too) before stimulating your cells. How long you stimulate for depends on your experimental question, but an overnight stimulation would probably be suitable for seeing divisions. You might need longer than this, as from memory the average cycle time for a lymphocyte is around 12 hrs. For the last 3-4 hrs of your incubation, you can add Brefeldin A and or Monensin to block the secretion of cytokines.

    After the stimulation (and blocking) period, you can wash the cells, live/dead stain, surface ab stain, fix, permeabilise, stain for intracellular cytokines, and wash. You can use any of the commercially available fix and perm mixtures for cytokines. This should give you the cytokine levels and the division number for all of your cells (i.e. you can compare cytokine outputs from cells that are dividing vs cells that aren't).

    Another option you could explore for cell cycle profiling is BrdU incorporation. 

    Are you using the 4-laser (UV351nm, V405nm, B488nm, R640nm) 13-colour LSR-II in the College of Medicine core facility? 

  • Mehmet Ates added an answer in Elevated Plus Maze:
    Do the elevated plus maze and radial arm maze have interfering effects?

    I am currently experimenting with the elevated plus maze (EPM) and radial arm maze (RAM) to test the functionality of the hippocampus after the injection of neurotoxic chemicals such as kanic acid. I test with the EPM on the first day and start habituating for RAM the next day. I habituate the rats for 3 days then start recording. My professor was concerned that the EPM may have an interference effect on the RAM. I wasn't able to find references on it either. Are there possibilities that the experiences on the EPM prior to the RAM affects the performances of the rats on the RAM?

    Mehmet Ates · Dokuz Eylul University

    I tell me always was is the best training time  1 day 3 day or 5 day or nothing the question is what is need and what can I measurer in my protocol. the mazes are a problem that can be  dissolve and learned, memorize and reuse it, your rats learning not the pathway of your mazes he learned this four steps if you match your rats again rats this never dissolved problems (naive) your rats are always the best in time. Sometimes you see in naive groups rats that can learning significantly in shorter time as the group and this in  al maze protocols.

  • Abou Oussama Mohammed Chouchani asked a question in Algeria:
    I am looking for this book. " The Barbary Coast: Algeria under the Turks Hardcover john wolf ?

    I couldn' find it  , even some pages from it ... I want to compare between its original copy and the translated one.

  • Sutripto Majumder asked a question in C-V:
    Can any body explain me that how do we get the LUMO and HOMO of a polymer from the C-V curve?

    About the HOMO LUMO of any Polymer

  • Niranjan Biswal added an answer in Teacher Education:
    How much is one year's worth of learning?

    One of John Hattie's suggestions is to decide how much a year's learning is for each student and then you can judge that student's success against that amount. While this seems like a good idea in theory, it leaves me none the wiser. How much exactly is one year's worth of learning. How can it be measured? What would the metric be? Content is the easiest to measure because it could conceivably be defined by an amount or quantity, but what about conceptual understanding? What would a metric be for that?

    Niranjan Biswal · Technion - Israel Institute of Technology

    I am agree with all the panel member's view but especially Rochel, Jyotsna, and Kimberly.

  • Bhattacharya Chanu asked a question in Cancer Therapy:
    How can we exclude chemotherapy induced nausea during cancer therapy and emotional issues?

    If  we can reduce fear,depression,anxiety ,fatigue increase feeling of well being, we can reduce nausea symptom a bit more ,,,

  • Kirsten Besemer added an answer in Information Literacy:
    What is a single word to express a condition that is neither healthy nor unhealthy?

    I have developed a questionnaire to assess healthy and unhealthy practices in Information literacy. For categorizing the data into three categories,  what term will be appropriate to express a condition that is neither healthy nor unhealthy( that sounds like indifferent)

    Kirsten Besemer · Griffith University

    neither

  • Chengming Wang added an answer in GATE:
    How to use a new version of a full-text to replace the uploaded version of the full-text (without page Numbers) on Research Gate?

    How to use a new version of a full-text to replace the uploaded version of the full-text (without page Numbers) on Research Gate?

    Chengming Wang · University of Science and Technology of China

    Thanks a lot

  • Patricia Ryser-Welch added an answer in Optimization Algorithms:
    What are the optimization algorithms that can be used for searching results from the internet?

    For my MSc thesis I am searching results for a particular course topic from the internet. The results which are links to the materials needs to be optimized. Can anyone suggest what optimization algorithms that can be used for this purpose?

    Patricia Ryser-Welch · The University of York

    Google uses a bio-inspired algorithm in its search engine. I would recommend you to use an hill-climber. You only uses better solutions to reproduce and replace individuals in the population. 

    Sound interesting.

    Pat

  • Anoop Kumar Srivastava added an answer in Soil Physics:
    What is the storage life of soil samples for conventional soil testing?

    The importance of soil testing in fertilizer recommendation is now beyond any doubt, especially with the intervention of geo-spatial tools-aided soil fertility variograms. These developments added another dimension of soil test interpretation.On the other hand, in conventional soil testing research or advisory  laboratories, the  soil samples are stored for different periods. In this regard, i request our learned colleagues to express their views on the following related issues:

    * How long , a soil after sampling  , can be stored without experiencing any change in physico-chemical properties?.

    * How frequently , different soil properties undergo chnges /.

    * Has any study been made to see the changes in soil properties in long term storage ?.

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

    That was the very purpose of floating this question . how long a  soil sample can be kept alive without changing the liveliness of the soil. no doubt , a lot will depend upon the  type of soil properties , we are looking at , and the type of land use , the soil samples come from , besides the soil buffering capacity , which is nothing but the entire functionality of soil in totality . Hope , Dr Nazir , Ms Reyhaneh and other esteemed colleagues will agree with me . 

  • Siddharth Kulkarni added an answer in Formamides:
    Can anyone suggest low solubility solvents for surfactants such as SDS, CTAB, SDBS etc?

    I have used diodomethane, ethylene glycol, formamide and toluene. 

    Siddharth Kulkarni · Indian Institute of Technology Gandhinagar

    Dear all,

    thanks a lot for your responses.  Is di-idomethane a good choice? I know that surfactants have a very low solubility in toluene. I am looking forward to calculating the surface energy of the surfactant adsorbed slides, using the contact angle data. These surfactants are highly soluble in water and hence, water contact angle data is not reliable. I think toluene-di-idomethane is a good combination. 

  • Siva Sivaramakrishnan added an answer in Brassica Juncea:
    What may be the problem in Southern Blot procedure that it detects the positive control but not any bands from transgenics?

    I am trying to find my transgene from Brassica juncea. I tried isolating DNA using CTAB, Urea lysis method as well as using Qiagen Kit. After all the procedure, during imaging, I am getting band only in the positive control (though the DNA samples were PCR positive) in all DNA isolated types. Kindly help me find out the problem.

    Siva Sivaramakrishnan · Acharya N G Ranga Agricultural University

    Your transgenic DNA copy number in the sample versus your positive control could be a problem.One other thing you can do is to mix a known amount of positive DNA with your test sample and see whether you are detecting it to make sure that the problem is with the transgenic DNA sample than with the detection per se.

  • Rajan Sharma added an answer in Stata Software:
    How might one give command on _n and _n+1,_n+2.......in a single command in STATA?

    I am using a data with multiple ids (sort of panel data) in STATA and trying to do something like this:

    by id: replace var1=. if var1[_n]==1&var1[_n+1]==1

    by id: replace var1=. if var1[_n]==1&var1[_n+2]==1

    by id: replace var1=. if var1[_n]==1&var1[_n+3]==1

    and so on. But it is tedious as there are as many as 50 repeated ids.

    Is there a short-cut for this?

    Rajan Sharma · University of Southern Denmark

    Hi Ariel, Thank you for the reply. Your code is exactly the one I am using (I had asked made slight error, I corrected it now!). It will still not work for all observations of the same id.

  • Apius Tjimune asked a question in Community:
    Do you behave and communicate differently online than you do face to face? Give specific examples?

    Any 1 tell me please

  • Boris Ivanov Evstatiev added an answer in Electronics and Communication Engineering:
    How do we investigate semiconductor devices in the educational lab?

    This autumn, I have to conduct with students of a new IT specialty a series of lab exercises related to study of basic semiconductor devices: ordinary, zener, light, tunnel and other diodes, bipolar and FET transistors, diode and transistor circuits... So, I temporarily leave the “kingdom” of my favorite analog circuitry where I deal with circuit systems and move to the lower level where I will reveal and show the secrets of circuit components. The problem that stands before me is how to do this in the best way...

    I have unpleasant memories of the way they conducted laboratory exercises in this discipline in the 80's, when I studied in the same university. I remember that I had to perform a series of programmed actions on ready-made laboratory setups enclosed in boxes so their internal structure remained hidden for me...

    That is why, I decided to conduct more interesting laboratory exercises with my students where they can conduct free experiments on flexible prototyping boards by all sorts of components instead of hard prepared experiments on closed laboratory setups. Thus I hope to motivate them by waking their curiosity and creativity.

    My idea is first to pose the problem on the whiteboard, then to find the possible solutions and finally, to implement experiments in various ways. Students can investigate IV curves of diodes and transistors at four levels:

    • manually - driving the circuit by a potentiometer and measuring the electrical quantities by digital multimeters or a digital oscilloscope in XY mode (shown in the first attached picture below)
    • semiautomatically - driving the circuit by a functional generator or simply by a 50 Hz transformer, and measuring the quantities by an analog oscilloscope in XY mode (the second picture)
    • automatically - by a data acquisition board equipped by an appropriate periphery (the third picture)

    It would be interesting for me to know your opinion about such an educational experiment. Whether it would be feasible or would be extremely difficult for students and, as a consequence, for me?

    Boris Ivanov Evstatiev · University of Ruse Angel Kanchev

    In my opinion one of the main problems with breadboards is that there are no longer labeled resistors on the market. All resistors use color codes, which makes it hard (in certain situations) to verify the circuit and discover connection errors. Also if there are multiple resistors it's hard for the students to decide where to connect the measuring equipment. How do others deal with this problem?