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  • Jordan R. Yaron added an answer in In Vitro Techniques:
    The factors that influence In vitro calcium availability result?

    We are checking on different sources of calcium and it is giving different result of the calcium availabiilty via in vitro study. It is suspected that the solubility of the calcium may become one of the factor. However, just wonder whether the molecular size, type of calcium sources (manually synthesis from raw sources or chemically synthesis), the sample preparation or other factors may influence as well. Hope to get further explanation. Thank you in advance! 

    Jordan R. Yaron

    We need more data about your system. Many things bind calcium and many reagent preparations are "contaminated" with calcium. What exactly are you trying to do and how are you doing it?

  • Jordan R. Yaron added an answer in Confocal Microscopy:
    Is it possible to collect Z-stacks from an opaque object using a laser confocal microscopy?

    Hi everybody

    I want to know if it is possible to collect Z-stacks from an opaque object using a laser confocal microscopy. In more general sense, Is it possible to construct a 3D image from an opaque object at all?

    Jordan R. Yaron

    I can only imagine one way in which it would possible to measure x/y/z-height of the object: affix the object to a glass substrate. Deposit a layer of fluorophore (like a FITC-albumin) over the entirety of the surface, including the top of the object and the substrate. Turn the glass over onto another piece of glass. Image the object "upside down," so that you see the top of the object first, then you see the rest of the glass substrate. The delta between the z-position that you see the top of your object and the glass substrate is the height of the object.

    Constructions will be near impossible. You need to image THROUGH an object to reconstruct it. And in most senses of the question, this whole idea would be virtually impossible, to my knowledge.

  • Sangwoo Shin added an answer in Nanogenerators:
    Are there research groups in the UK who have current active interest in Nanogenerators?

    Are there research groups in the UK who have current active interest in Nanogenerators and e.g. links to Beijing Institute on Nano Energy and Nanosystems, Georgiatech in USA or SKKU in Korea?

    Sangwoo Shin

    Hi Max. Sohini Kar-Narayan at Cambridge works on this topic.

  • Saikat Sen added an answer in 13C:
    How can I obtain the NMR spectra of vinorelbine?

    how can obtain the NMR spectra (13C, and DEPT) of vinorelbine?

  • Amipara Manilal D added an answer in Wireless Communications:
    How do you understand the coexistence in Wireless Communication Systems?

    The coexistence of wireless devices (WDs) represent an important challenge. As far I understand the coexistence concept considers at least two considerations - spectrum (frequency) & coverage area- and I include other one: time. With these three 'parameters' I can describe, in wide sense, the coexistence but I do not know if my context is complete, then I would like to know your idea,

    -How do you define Coexistence of WDs?     

    -What parameter must I consider to define it?

    Your comments are important for me.


    Amipara Manilal D

    The coexistence of different wireless devices is the presence of one do not allow the others function to do or disturb others beyond tolarable limit Function of WD  is to recover message signal "Faithfully". The function expected to carry out in the activity region. The active region you defined in three parameters are alright. Additionally, I would say amount of power radiated. It can either created interference or "JAMMING" effect.

  • William Patrick Leonard added an answer in Higher Education:
    How can we typify higher education admission systems?

    This question is based on a new project I am coordinating called SASH. One way is through the concepts open admission systems vs. selective admission systems vs. mixed systems. However, we think that selection for admission happens at least 3 times during the admission process: 1) by the school system, 2) by the prospective student and 3) by the HEI(s). 

    Does anyone know of alternative approaches to classifying HE admission systems? Thanks for any references.

    William Patrick Leonard

    To my naïve way of thinking there are two general  approaches to undergraduate admission—selective and open.

    Selective schools employ their own set of standards to guide admission decisions. Their criteria might include SAT or ACT scores, rigor of secondary school curriculum, GPA, essay, etc.  Some are highly selective, while others align along a descending continuum. Their processes are a mix of art and science as even with their standards a few students are assigned to some remedial work.

    The open schools normally require only a high school diploma or GED certificate to secure admission. They open their doors to aspiring students who would have been otherwise be  shutout.  They also increase their tuition revenue, which helps to balance the budget.  It is not, however, a win-win. Many students must take remedial coursework before they work on their degrees. Is there an ethical challenge accompanying the institution’s financial gain?  Open admission institutions tend to have relatively low retention and graduation rates when compare to the selective.

    For a look a graduate admission, you might want to review:

    Inside Graduate Admissions

    Merit, Diversity, and Faculty Gatekeeping

    By Julie R. Posselt

    Publication: January 2016


  • Jordan R. Yaron added an answer in mRNA:
    Averagely, how many copy number of each mRNA in a single cell?

    I know it is less than 1000. Could anyone give me the link or copy of the literature?

    Jordan R. Yaron

    Hi Liqiang,

    Figure 3A in this paper may be helpful:

    In short, when measured in single cells, most protein coding genes are expressed at 1-50 copies per cell.

  • Tao Liu added an answer in Protein Structure:
    Can anyone help me how to draw 3D structure of proteins? which software i can use?

    I want to draw 3D structure of Viral protein but don't have idea about it. if someone could help.

    Tao Liu

    Hi Swati. There are many approaches about visualization of 3D-protein structures. It depends on how much information you've had. If you have all-atom coordinates, you can use VMD (Visual Molecular Dynamics), developed by uiuc, to show them. But if you only have sequence information, you may need some online servers to determine its possible 3D structure at first.

    Good luck.^_^

  • Abdul Mannan Rana added an answer in Sports Economics:
    Can anyone recommend any recent research articles on the dimensions of brand equity in professional sports teams?

    Need help to access any recently published research  articles on the dimensions of brand equity in professional sports teams.

    Abdul Mannan Rana

    Check this out.. it may help you in an indirect way..


  • Paul Rushton added an answer in Next Generation Sequencing:
    What are the best (and best value) qPCR machines and what do they cost?

    I am setting up a new lab and want to cost out a qPCR machine as part of the start up.

    It is proving very difficult to find a quote without talking to a rep as almost all of the web pages say "ask for quote" and at the moment I just want a ballpark idea for budget purposes.

    Could I get some input on good systems and what they cost?

    Comments on ease of use and value for money would be useful.


    Paul Rushton

    Eigentlich hatte ich was anders vor, und zwar meine Familie und ich fliegen nach Deutschland um alles ueber qPCR von Euch zu lernen - wie ist das Bier in Saarbruecken?

  • Ayu Dwi Nindyati added an answer in iTEM:
    Can anyone suggest, how many items we need to measure psychological attributes (in ideal terms)?
    I am running my research that contains five variables. Some of them I developed the measurements by myself. In the middle of the construction of the measurement my colleague asked about the amount of item. I have already read some books but I can't find the fit answer. Can anyone explain?
    Ayu Dwi Nindyati

    Dear Orlik,

    Thank you for your answer


  • Khan Muhammad added an answer in Computer Security and Reliability:
    What is the best Model for assessment a framework security ?

    Dear all,

    I proposed a framework security, but i want to determine exactly which is the best model for  assessment this framework  

    Khan Muhammad

    Dear Alnaseeri,

    Could you please describe it in more detail about the type of security framework that you have developed?



  • Shiuh-Hwa Shyu added an answer in OpenFOAM:
    One model for different Reynlods numbers?

    using openFoam, I have to compare the behaviour of the fluid inside a pipe flow at different speeds, that ranges from laminar to Turbulent flow. The problem here is that I need to stick to one model, because different models behave differently, which results in showing sudden drops in the curves. At the same time, one model is not valid for a such a range of Reynolds number. For example I think I would rather use laminar until Re<2000 and then switch to RANS, but the result is a sudden drop in the curve. Can I actually use RANS from the very beginning (Re<200) ?

    Shiuh-Hwa Shyu

    The phenomenon you've seen is common and correct. If you insist using one model to cover laminar, transition and turbulent, you can choose RNG model.

  • Luis Manuel Hernandez Ramos added an answer in LaTeX:
    What is a suitable LaTeX editor for mathematicians?

    I am looking for an easy-to-use free LaTeX editor that is friendly to mathematicians who include many mathematical equations in their research articles. Do you have any recommendations?

    Thank you!!

    Luis Manuel Hernandez Ramos

    I prefer Texmaker

  • Khan Muhammad added an answer in Information Security:
    What is information security?

    Dear collegues. Your answer is highly appreciated. I think the points that you mentioned, have been prolific for me and many of RG members.

    Information security - the state of preservation of information resources and protection of the legitimate rights of the individual and society in the information sphere. Information Security - is the process of ensuring the confidentiality, integrity and availability of information.

    With kind regards, Shafagat

    Khan Muhammad

    Respected Prof. Hashim Tahir and other RG members,

    Thanks for providing your valuable comments continously on the topic. I would like to add that the information security community mostly termed these three requirements as "CIA".  See section 2.5.2 in the attached paper.

    With kind regards


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The appropriate collection and consumption of electronic health information about an individual patient or population is the bedrock of modern healthcare, where electronic medical records (EMR) serve as the main carrier. This paper first introduces the main goal of this special issue and gives a brief guideline. Then, the present situation of the adoption of EMRs is reviewed. After that, the emerging information technologies are presented which have a great impact on the healthcare provision. These include health sensing for medical data collection, medical data analysis and utilization for accurate detection and prediction. Next, cloud computing is discussed, as it may provide scalable and cost-effective delivery of healthcare services. Accordingly, the current state of academic research is documented on emerging information technologies for new paradigms of healthcare service. At last, conclusions are made.
      Full-text · Article · May 2015 · Computers in Industry
  • Matthew P Donohue added an answer in EPR:
    Opinions on quartz or glass tube cleaning?

    Dear EPR community,

    I'd like to know a reliable method to clean out EPR tubes which previously held a sample in solution, particularly in the case of samples containing transition metal species.  I'm sure some solution of EDTA is involved, but I'd like hear your tried and true methods (solution(s) composition, soak time, drying, etc.).

    Thanks in advance,


    Matthew P Donohue

    Thanks Alex; cutting your own tubes certainly makes life easier than washing old ones. I considered using some type of chelating agent to remove any Cu(II) species adsorbed to the tube walls, but of course it is more sensible to use new clean tubes for an experiment.



  • Stefani Tucker asked a question in Self-efficacy:
    Does anyone have the computer self efficacy scale tool?

    I have found an article by James H Brown on how to use the scale but unable to locate on the site.

  • Gregory L Wilson added an answer in Randomized:
    How to generate sample from Multinomial Distribution?

    Let U1, U2, ... ,Un be uniform random numbers between 0 and 1. How would you use Ui's to obtain a sample from the Multinomial(n, p1, p2, p3) distribution?

    Gregory L Wilson


  • Anirudh Kumar Satsangi asked a question:
    Is 'soul' temporary or eternal?

    In my view soul is eternal.

  • Satoshi Irei added an answer in Gas Chromatography :
    How can I calibrate my GC (Agilent 7890A) for ppm concentration of methanol?
  • Penny C. Wang asked a question in Foreign Languages:
    What are the top books/articles which distinguish second language from foreign language in definition and pedagogy?

    What are the top books/articles which distinguish second language from foreign language in definition and pedagogy?

  • Khan Md Taufiqul Arif asked a question in C57Bl/6:
    Which LPS is the best to induce sepsis?

    Assay: Cytokine profile and Survival rate determination

    Animal Model: C57BL/6 mouse (6weeks)

    LPS: E. coli: O111:B4, O55:85, O127:B8, Salmonella enterica ser. enteritidis/typhimurium

    Dose: 15mg/kg bw in 0.9% NaCl

    Which one should I use?

    Are there any rules/criteria for selecting LPS? 

  • Rajesh Chaudhary added an answer in Diabetic Foot:
    Is there anyone using honey for the dressing of wounds? why aren't the people convinced about it's efficacy in wound healing?

    in  my clinical practice i've been using honey for the treatment of venous ulcers, bed sores, burns, necrotising fascitis, burst abdomen and even in case of diabetic foot too. i heve seen wonderful results. there is scarcity of data in terms of trials and most of the surgeons don't agree to accept it but is a good debriding agent.

    Rajesh Chaudhary

    Thanks aharon....

    I agree.... And this is why people are circumspect about its use. But it is a very good and cheap alternative. 

  • Ariella Barry asked a question in Curcuma:
    I need help with making an experiment with CHO cells?

    I am in a cell culturing lab and I need to create me own experiment that will last about a month. I am using CHO cells and I want to add two different things to the media to increase growth rate of the cells. I am adding curcuma NF-kB but i do not know what else to add.

  • Abiola Adeosun added an answer in Shimadzu:
    How I can determine Iron concentration in an aqueous solution using a Shimadzu uv 1800 spectrophotometer?

    How I can determine Iron concentration in an aqueous solution using a Shimadzu uv 1800 spectrophotometer?

    Abiola Adeosun

    Try this article http://www.sciencedirect.com/science/article/pii/S1658361215001389

  • Rathish Nair added an answer in Educational Evaluation:
    How to calculate the cost of education and the productivity of the graduates?

    Few days ago I raised a question on 'Can we measure EDUCATION in terms of money?' and this is a follow-up question raised on the basis of the received answers. For the reviewing the discussion on the first question you can visit the link attached herewith.

    Rathish Nair

    Cost effectiveness is estimated in lines with the objectives of the program/course and the determined measure of effectiveness for each program/couse.

    for example, for the objective of Program completions - Number of students completing program will be a measure of effectiveness 


    Reducing dropouts - Number of potential dropouts who graduate

    Employment of graduates - Number of graduates placed in appropriate jobs

    Student learning  - Test scores in appropriate domains utilizing appropriate test instruments

    Student satisfaction - Student assessment of program on appropriate instrument to measure satisfaction Physical performance - Evaluation of student physical condition and physical skills

    College placement - Number of students placed in colleges of particular types

    Advance college placement - Number of courses and units received by students in advance placement, by subject

  • Sudong Shang added an answer in AMOS:
    If moderators are categorical?

    If moderators are categorical, like gender, how to test the model in Amos and plot the significant effects? Thanks

    Sudong Shang

    Thank you so much, Khan Taufique and Daniel Wright. 

  • Rahimi Ali added an answer in Renaissance:
    Does anyone know who the artists are the first to introduce perspective in painting art?

    Whether it happened before Renaissance time?

    Rahimi Ali

    Dear Lilliana,

    Thanks for informative  discussion ,  I was just wondering if Annunciation could be utilized in non-religious or non christian works of art as well.  Do you believe in the universality of this movement?

    best wishes