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  • Bhanu Mantri added an answer in Cryo-TEM:
    What are the factors on which Blotting force for cryo sample preparation using vitrobot depends?

    I have been preparing the sample for the cryo-TEM of the fibroblast cells, ribosomes and liposomes but for each sample i have to look for the blot force, blot time, drain time, etc. So I think is that the blot force is the main part to look for and it depends upon the thickness of the specimen you want to blot but I am quite confuse how to determine the blot force for samples.

    Bhanu Mantri · Amity University

    Edyta Reichman i am very much thanks for the answer so you mean to say that for every sample the blot force is need to be adjusted with hit and trial method. and drain time and wait time do not play any major role for vitrification process.?

  • Ge Songsheng asked a question in Isotopes:
    How isotopic data were evaluated in terms of alteration effect ?

    There is a suite of altered volcanic rocks (from basic to felsic samples), how can I evaluated the isotopic data (Sr, Nd, Pb) were affected by the alteration effect? 

  • How does gravity affects Schrodinger wavefunction?

    How does gravity affects Schrodinger wavefunction?

    Bhushan Bhoja Poojary · NIMS University

    Yes Schrodinger wave function

  • What is the difference between productivity and efficiency?

    There are two firms A and B

    Firm A uses 5 units of raw material, 2 units of labor, 3 units of capital  to produce 6 units of output in one year.

    Firm B uses 10 units of raw material, 2 units of labor, 3 units of capital to produce 10 units of output in one year.

    Would I say, Firm A is more efficient than Firm B because it is using less raw material per unit of output with the same given labour and capital; whereas Firm B is more productive that Firm A, because it is producing more output per given units of labour and capital?

    Does efficiency pertain to the exhaustible resource(raw material, or time for that matter) per unit of output, where as productivity pertains to economic resources (labour capital, land)?

    Niharika Joshi Bhatt · Rajiv Gandhi Institute of Petroleum Technology

    Dr. Lechman: Could you give an example?

  • What does a negative peak in a UV spectrophotometer reading suggest?

    I am carrying out a degradation study and I am scanning the media extraction from 190-300 nm. At 0 Hrs I get a peak at 230 nm and 265 nm. But after 24Hrs the 265 nmpeak decreases while a negative peak is observed at 230 nm i.e. a small peak below the base line. I am using methanol as blank and I am using methanol in baseline measurement.

  • Michael Brückner added an answer in Google Scholar:
    How can I add my citations inside google scholar?

    Some of my paper have citations inside scopus database but the same paper not cited inside google scholar database.

    Michael Brückner · Naresuan University

    Ruzinoor,  you need an account on Scholar (with a verified institutional email address). After that, Scholar crawls the databases and automatically adds your publications to the list. If you feel the need to add something, use the Add button on the 'My citations' screen.

    Follow the advice given here: http://blog.impactstory.org/make-google-scholar-better/

  • Are there any combinatorial studies on perturbation theory?

    Are there any combinatorial studies on perturbation theory? Can we relate graph theory to that area? If so, please suggest some useful references for a beginner like me.

    Sudev Naduvath · Vidya Academy of Science & Technology

    Thank you Professor Behnam Farid. Let me refer the book you suggested.

  • How to classify your students through the quality and nature of their questions?

    Some students ask smart questions, while others ask stupid, silly, ridiculous, and meaningless ones. Some of them ask wise questions while others ask pointless and aimless ones. Some are interested only in issues that would be most likely asked in the exam. Some ask irrelevant questions to divert attention.

    Please provide us with your personal experience and opinion.

    Leonard Goeirmanto · Universitas Mercu Buana

    in informatic subject, if my students' questions have a relation to theory or algorithm, I specify them into smart question.

    but sometimes they just asked some points which are already discussed before because they haven't understood, so I think these are ordinary questions.

  • Urjita Sheth added an answer in Cell Line:
    Which cell culture products should I use for caco2 cell culture? Can anyone tell me along with the catalogue numbers?

    i am doing permeability study using caco2 cell line and i am not getting which reagents i should use for that and also i should use 6 well plate and inserts or 24 or 96 well plates and inserts

    Urjita Sheth · C. G. Bhakta Institute of Biotechnology

    @Ahmed Elbediwy thank you sir

  • Nikhil Aggarwal asked a question in HOMO-LUMO:
    Is it possible to have two excited states from HOMO-1-> LUMO and HOMO-> LUMO+1 with different weighing factors and separated by approx. 20 nm ?

    Is it possible to have two electronic excited states results from HOMO-1-> LUMO and HOMO-> LUMO+1 transitions with different weighing factors and separated by approximately 20 nm ?


  • Asking about storing Lactic acid bacteria in freezer using glycerol?

    Hi, I have problem when storing lactic acid bacteria employing glycerol 5% and 50%, and then problem occurs in our lab, the freezer's temperature down until -10 degree. after one month I culturing my bacteria but unfortunately they slow growth. only small colony grow. Any body can help how to secure them?

    Best regards

    Vijay Kothari · Nirma University

    You may try with storage of bacteria in simple sterile distilled water, at room temperature.

  • Ranjeeth Kumar Sundar added an answer in Qualnet:
    QualNet or MATLAB which one is better for Wireless sensor networks?

    Wireless sensor networks are used for applications of smart grid environment.

    How can we obtain QualNET. 

    Ranjeeth Kumar Sundar · SASTRA University

    qualnet is good especially when you work with security features of wireless sensor networks... since qualnet is having special additions for dealing security of wsn....... but qualnet is commercial software need to buy...........

  • Patrick Batoon added an answer in Ions:
    What are the best methods and instruments to detect Ferric Ion in borosilicate glass system in water?

    I am trying to find the best method to detect ferric ion in borosilicate glass system after be soaked in distilled water. The raw materials that I have been used are Si2O-Na2CO3-FE3O5-B2O3. 

    Patrick Batoon · University of the Pacific (California - USA)

    For trace detection of Fe (0, 2+, 3+) in solution, I believe the lowest limits of detection will come from Inductively Coupled Plasma by optical emission spectroscopy (ICP-OES) or by mass spectrometry (ICP-MS).

  • Srinivas Pittala added an answer in Mouse Models:
    Comparison of Multiple Sclerosis mouse models?

    I want to start my first animal based experimental study. I chose Multiple Sclerosis. Can anyone provide me with a source summarizing different MS mouse models.

    Srinivas Pittala · Institute of Genomics and Integrative Biology

    EAE Model is good one and complicated also.

  • nor lailatul wahidah Musa asked a question in Hearing:
    How to evaluate the effect of elevated atmospheric CO2 on plant distribution pattern?

    I'm trying to access the effect of elevated CO2 on plant distribution but I didn't have any previous distribution data to compare. I'm much delighted to hear any suggestion from other researchers regarding this topic. Tqvm 

  • Burkhard Koehler added an answer in Polymerization:
    Is there any single solvent in which N, N Diethyl aminoethyl Methacrylate (DEAEMA) and beta cyclodextrin are soluble?

    Beta- cyclodextrin has water solubility but when this solution is mixed with above monomer. polymer undergoes precipitation and polymerization doesn't occur. Although initiator and cross linkers are there.

    Burkhard Koehler · RWTH Aachen University

    DMSO or DMSO-water or DMSO-alcohol mixtures may be appropriate.

  • Lawrence Broxmeyer, MD added an answer in HIV:
    Can we prevent infections like TB in HIV cases?

    As we know that the cause of death in HIV positive cases is not HIV infection itself but other infections like TB, so if we can inject the CD4 (total WBC pellet can be used) treated with agents that can eliminate the CCR5 and CXCR4 receptors (which are proteins) from the CD (by using specific enzymes) or can bind with them so making them unavailable for HIV, so that we can reduce the chances of secondary bacterial infections, improving the immunity and health status and in terms prolonging the life of Patient. Also we can use this type of specifically treated cells in various diseases (specifically immune deficiency diseases and diseases in animals) to improve the condition of patient. Can we do that?

    Lawrence Broxmeyer, MD · NY Insitute of Med Research

    Clotrimazole is an antifungal prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of certain fungal infections, including tinea versicolor that is specifically caused by the fungus Malassezia furfur and candidiasis that is specifically caused by the yeast Candida albicans. The troche (lozenge) formulation of clotrimazole is approved for the treatment and prevention of only a certain type of candidiasis—called oropharyngeal candidiasis—in certain people with weakened immune systems. Clotrimazole is also available as an over-the-counter medicine for topically treating various skin infections, such as athlete’s foot.

  • In General relativity, what is a space-like geodesic - physically?

    Given a metric it is certainly possible to find space-like geodesics, but what are they physically? They are clearly invariant under coordinate transformations and so, by my reckoning they must have a physical basis. Candidates might be, for example, a stretched string. This is not a space-like geodesic, not least because it is a world sheet, i.e. a two dimensional object in R^4. A level set of constant proper times on the string, however, certainly gives an invariant space-like curve, but probably not  geodesic.

    Vikram Zaveri · Independent Researcher

    Dear Azzam K Almosallami:

    In periodic relativity, Lorentz transformation is also generalized and this new formalism reduces to Lorentz transformation of SRT as a special case. Therefore with the generalized Lorentz transformation of PR it is possible to describe gravity. Many physicists do not consider general relativity as as a generalization of special relativity. The name of the theory is misleading. The problem of objectivity that you mention is due to (1) non-relativistic nature of Schrodinger wave equation and (2) purterbative treatment of Dirac's theory. Both these problem are removed in the theory given below. This revised quantum theory and periodic relativity combine to give the unified theory. So this theory not only solves the problem of objectivity but also goes one step further than that.

  • Michael Issigonis added an answer in Minorities:
    Does anyone know of minority coping strategies in the aftermath of the ethnic conflict?

    What are the accepted theories or models that can be applied to the case of minority that facing ethnic discrimination after the inter-ethnic conflict?

    I am writing my MA thesis on ethnic minority discrimination after the conflict and their everyday life predicaments, as economic cultural and political discrimination. I want to use some models or a theory to this case, except of nationalism. Can you suggest me some? Thank you! 

    Michael Issigonis · Brandon University

    You can study old or recent examples from history/UN reports. People who have suffered discrimination get a "second chance" by getting better organized. How? By keeping customs, traditions & language by education & festivals. Don't be afraid to show to the world, because the world will notice and react to any discrimination, sooner or later. If they hesitate to react, the same fate will happen to them.

  • Burkhard Koehler added an answer in Polyurethane:
    How can I increase molecular weight of polyurethane?

    I am working on polyurethane since last year but I can not succeed in the synthesis of  polyurethane.i am going to leave this project. Please tell me tricks for the synthesis of polyurethane.

    Method 2 step linear water dispersible polyurethane

    1st step

    TDI (5mole) + DMPA (1mole) + PEG-1500 (2mole) + Acetone or 1,4-dioxane as solvent

    functionality of TDI, DMPA, PEG is 2 each and catalyst is DBTDL

    2nd Step

    Pre-Polyurethane + Ethylene diamine (2mole) + water

    Resulting polymer is linear water dispersible polyurethane 

    Problems I faced are 

    1. PU is viscus like honey rather than it solidify on dry, perhaps molecular weight remain low.

    2. Polymeric properties does not produced. 

    3. How can I increase polyurethane molecular weight?

    Please help me in this case  how to maintain NCO/OH ratio 1:1

    How high molecular pu synthesized

    conditions, catalyst, solvent what ever . advise me otherwise i will leave this project and start new project for my Ph.D reseach. 

    I am very upset after one year work no progress;

    Burkhard Koehler · RWTH Aachen University

    After formation of the prepolymer in acetone you should determine the NCO content by titration and add the equivalent amount of diamine calculated from experimental determined NCO content. The equivalent amount is in most cases a litte bit different from the theoretical two moles. Not exact stoichiometry is in most cases the reason for not sufficient molecular weights.

  • How can I solve a problem of water turbidity in the determination of labile carbon with permanganate?

    I am currently trying to determine labile carbón with permanganate, and I am using the following process. Firstly, I am taking 5 gr of soil sample, adding 20 ml of permanganate, shaking for 2 minutes, and after waiting 10 minutes to leave particles precipitate, I am taking 0.5 ml and filling with distilled water until 50 ml, and then I am measuring the absorbance in a spectrophotometer at 550 nm. The problem is that in some samples, there are so much turbidity in water, and I am sure that it has an influence in my measurement of absorbance. I do not wanna centrifugation because I think it might be so strong, and some other fractions of carbon besides labile carbon might react, giving me a wrong measure. To solve the problem, I was thinking to prepare a blank test with the soil, following the same procedure mentioned, but this time without permanganate, only to measure the absorbance of the particles. In your opinion, what should I do?. I will really appreciate your help.

    Carlos Matias Romero · Montana State University

    Luciana, I'm currently working on POXC determination... it seems that you are using the Weil method. Are you preparing the 0.2M KMnO4 solution with 1M CaCl2?!  Try a higher molarity. Although I run hundreds of samples and I never had a turbidity problem. Filtering the samples won't help since the nature of POXC doesn't necessarily represent the dissolved organic carbon (those particles that pass 0.45 um). Plus, the method was proposed as a cheap and easy alternative to measure labile C (those filters are expensive). If you centrifuge the samples, you will probably release recalcitrant compounds. So, try a higher molarity of CaCl2. Also, after those 10 min, you should pipette from the top!

    Hope it helps.


  • Abdul Raheem asked a question in Gas:
    What is difference between Mol% and Vol%,,?

    While looking at articles, I have seen that many of researchers are mentioning vol% or Mol% of gas from the gasification of biomass like 31 vol% or mol% of Hydrogen and so on for other gas composition, I would like to knw that if this Hydrogen is 31by Vol % then how much it will be into Mol% or both are same.....?

    Another thing i want to add that a gas mixture, they can only report into mole percent since the GC measures the molecules, not the volume.

  • I would like to isolate the pure compounds from crude extract of my plant sample, how?

    please suggest me methadology

    Muhammad Siddique Afridi · Pakistan Council of Scientific and Industrial Research

    Yes, use steam distillation for extraction of essential oil and hexane for fame or fixed oil in soxhlet s  apparatus.Thus you will be able to remove oil, fatty, waxy and other non-polar substances from  plant extract and do their GC-MS analysis of the oil extracted. Do phytochemical screening and try for the isolation of those group of compound which were identified during phytochemical screening. For further  isolation and purification, of these identified group of compounds, prepare your extract most probably in EtOH, Do TLC of your crude extract , when you found some spots on run TLC, then try for isolation. You can use selective method of extraction  for different  groups like alkaloids , flavonoids etc or use column chromatography. Do their TLC again of different fractions collected from column. Isolate and purify each single spot on TLC or PTLC. Find melting point, UV, FTIR, HPLC, GC/MS and NMR of the isolated spot  or compound. At last you will get a group of data about a particular isolated compound. 

  • Anna Popova added an answer in Glass:
    I have coated TiO2 thin films over glass slide using sputtering.Is it possible to diffract only the thin films on a glass slide using XRD?

    XRD measurements of TiO2 thin films coated by sputtering method gives only amorphous peaks corresponding to SiO2 (glass). How to make XRD measurements of the thin films (TiO2) without the background glass (SiO2)peaks?

    Anna Popova · Kemerovo Scientific Centre SB RAS

    Hi, Gokul.

    You shouldn't use Al-foil as its peaks are closed to TiO2. Cu-foil is more appropriate substrate.

  • Ron Reiserer added an answer in Nanopores:
    What software can be used to simulate flow through nanoporous membranes ?

    I need a tool to simulate flow of gas/liquid through nanoporous membrane , for observing viscosity changes , velocity profiles , etc,.

    Is there any free (opensource) software available ?

    Ron Reiserer · Vanderbilt University

    I suggest Elmer GUI. It is a bit difficult to get started with, but once get the hang of it, you'll love it.

  • B.R. Rajeswara Rao added an answer in Pharmacognosy:
    Can anyone provide ICMR (Quality standard of Indian Medicinal Plants) monographs of the following drugs?
    If possible please send the maximum possible drugs

    If you have soft copy of this book then please send me.

    1. Galo- tinospora cordifolia

    2. Dhamaso- fagonia cretica or f. Arabica

    3. Dhatakipushpa- woodfordia fructicosa

    4. Chitrak- plumbago zeylanica

    5. Fenugreek- methi- trigonella foenum

    6. Arjuna bark- terminalia arjuna

    7. Kaalijiri- centratherum anthelminticum

    8. Malkangni- celastrus paniculata

    9. Chakramadu- cassia tora

    10. Apamarg- achyranthus aspera

    11. Eclipta- bhangaro- eclipta alba

    12. Karen- nerium indicum

    13. Amla- Phyllanthus emblica
    B.R. Rajeswara Rao · Central Institute of Medicinal and Aromatic Plants

    Dear Bhatt

    You are most welcome.

    If you do not mind my suggestion, you should understand that copyrighted publications can not be freely uploaded on RG. In case you are keen on ICMR publications you should contact ICMR or one of its constituent Institutes for providing free copies or free access to their e-library or hard copies. In Hyderabad, we have National Institute of Nutrition (NIN), an ICMR institute. You can check ICMR website for more institutes nearer to your place and try to access their library.

    Good luck.

  • Bharati Kharade asked a question in E-Governance:
    What are the research challenges in G-governance to implement Big Data?

    I need to have few ideas regarding research challenges and opportunities in e- governance  using big data for different departments of government. How Big Data can be implemented in administration, education, tourism, agriculture fields etc?

    Please let me know

  • Malachi Noked added an answer in Metal Oxides:
    In carbon/metal oxide nanocomposites, which shape of metal oxide will give high specific capacitance (F/g)?

    I have prepared activated carbon/iron oxide nanocomposites with different shape of metal oxide. i.e. spherical and rod shape of metal oxide nanoparticles were encapsulated carbon material. I have measured the specific capacitance for the same samples. Rod shape particles are less capacitance values than spherical shaped particles. 

    So give me an idea about relation between shape and specific capacitance.

    Many thanks in advance!

    Malachi Noked · University of Maryland, College Park

    Dear Dr. Ranjithkumar

    First you should make sure what are the changes in the porous structure of the hosting carbon material, caused by the impregnation of the oxides. One possibility is that the Rod Shape are either more destructive or clogging the porous structure.

    Second, you should make sure to have similar loading amounts  for "fare" normalization.

    The kinetics of adsorption can also be highly important in your case, you can test adsorption kinetics in gaseous phase and not only BET. 

  • FC Prinsloo added an answer in TRNSYS:
    Rural village electricity (heat, power) load profile, demand side consumption requirements for user, household or microgrid dataset to download ?

    We are working on an integrated synthesis TrnSys model for a parabolic dish based thermal electric power generation system in a micro combined cooling heating and power (micro CCHP) configuration, with active demand response and interactive energy management and control.

    Looking for real-time data (ie .xls or .xlxs or .csv or .ods or .zip time series data or profile sequence data) to evaluate computer simulation models for a solar thermodynamic trigeneration system (combined cycle data or daily household load or user demand pattern data). Require such powerplant or household usage datasets for use in training artificial intelligent scheduling and multi objective control aspects in isolated or rural microgrid and smartgrid.

    Would appreciate if anyone could inform of available data for community, residential, shack neighborhood or rural village settlements in Africa, South America (e.g. Brazil, Argentina, etc), China, India. Alternatively any other load cycles for any other area will also be helpful (including smart household data).

    FC Prinsloo · University of South Africa


    Interesting load profiles from disaggregated smartmeter data would also be valuable


    Ine can also find very interesting information in rural electricity and heat load profiles from a google or bing image search using the phrase

    hourly load profile throughout a year

    Finally I recommend reading 

    Benefits of Decentralised Production of Heat and Power for small energy consumers in the spotlight


    as it provides valuable insights into autonomous and stand-alone remote energy systems, off-grid rural power systems and combined cycle cogeneration heat and power systems (CHP and CCHP) such as in your project. 


  • Does anyone have knowledge of case studies of physical rehabilitation after a latissimus dorsi transfer?

    I am especially interested in the way the latissimus dorsi can relearn its new function. Is the fact that the patient already had a reversed shoulder prosthesis of any influence? 

    Corey Mcgee · University of Minnesota Twin Cities




    Does this help? Are you looking for a rehabilitative protocol?