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  • Krishnan Umachandran added an answer in Learning:
    Should a teacher focus on 'rigorous learning' or 'learning with entertainment'?
    It has been seen that many teachers in universities have become entertainers rather than focusing mainly on value-addition and learning. A lot of time gets devoted to pleasing the students; knowing them personally; building good relations with them; and telling jokes and creating humour; the focus becomes more of good feedback than rigor. Keeping the audience motivated is good for effective teaching; but since a lot of time goes in entertainment less time remains for analysis and conceptualization. What is your preference and why?
    Krishnan Umachandran · Nelcast Ltd.,

    I agree @ Marjorie, that based on the students learning capacity the customization of teaching has to happen. 'Rigorous learning' or 'learning along entertainment' individually stand poles apart. So we need to combine a MIX in such a way that is tuned to the requirement.

    Mostly "Entertainment" mix is only an attention seeker when the students get bored, therefore to realign them towards content learning, the slight appropriate dosage of fun is required.

  • Pradip Kumar Kamat added an answer in Transgenes:
    How can I make efficient transgene expression in mice brain?

    Usually when we transfect the gene into this organism we sometimes get good expression but also sometimes bad expression. Is there any precaution or protocol to make most efficient transfection and gene expression?

    Pradip Kumar Kamat · University of Louisville

    Dear Dr. Jenkins My transfecting agent is lipofectamine and delivery method is intracerebral. Region is whole brain and cells are neuronal as well as non neuronal. Ihave both reporter trransgene and therapeutic both. I want stable integration. Strains are Male (8-10 weeks)  wild type and CBS knockout mice. 

  • Arvydas Guogis asked a question in Societies:
    Is Erich Fromm's famous question "To have or to be?" still relevant in contemporary societies?

    Materialistic values during the least 30 years have been more entrenched than it happened several decades ago when Erich Fromm posed his famous question "To have or to be?". Is this type of neo-Marxist argumentation still relevant in contemporary societies? 

  • Ammar Abdullah asked a question in Likert Scale:
    Which statistical analysis should I use to analyse Likert scale survey

    Hello group,

    I have a huge set of data came from a survey by using 40 questions on likert scale with five levels (1: Strongly disagree... and 5: Strongly agree). The data has one independent variable and 50 depended variables including the 40 questions of the survey plus 10 personal questions about the employees who did the survey (age, gender,...etc.). The project is trying to answer what drive people attitude on safety culture? I'm looking for the appropriate methods to analysis the data.
    I would really appreciate any help.

  • Hoang Son asked a question in Vietnam:
    Unidentified plant from Vietnam

    Unidentified plant from Vietnam: Can anyone help?

  • Elsa Dent added an answer in APACHE:
    Is there another prognostic calculator I should be using other than the APACHE III in adult medical patients?

    In a study measuring the burden and impact of malnutrition in adult medical patients we have proposed to use the APACHE III in the view that there is not a similar outcome prediction calculator we can use. However, the APACHE III (or earlier APAHCEs) have not been validated in the general adult medical patient. Can anyone advise me if they are aware of any studies that have validated APACHE for this population group or if there is another calculator we should be using?

    Elsa Dent · University of Adelaide

    A lot of hospitals in Australia tend to use HARP on admission to acute care for adults of all ages, although this has a low prognostic ability. Here's one paper that may be able to help you


    I research the same topic as your question, although in older people. eg I've just done a paper comparing prognositc tools in the acute hospital setting for older patients patients, including APACHE II, Charlson's Co-morbidity Index, Frailty Index and HARP.

  • Rakesh Sharma added an answer in Vegetable Crops:
    Why do red chilli fruits split/crack?

    This year I have many chillies that spllitted in my garden. I tried to find causes of it, but not seen. This may be a researchable issue for agricultural experts working in vegetable crops or spice crops. Please let me know if you have any answer to this problem.

    Rakesh Sharma · Dr. Yashwant Singh Parmar University of Horticulture and Forestry

    Respected sir I am a Ph.D student in dpt. of Vegetable Science at UHF Nauni-Solan. I am working on tomato & I have also seen many cracked fruits during my research trial. Its either due to heavy rains after a prolonged dry period or due to Boron defficiency. I think similar is the case with chilli fruit cracking. So i suggest borax spray on your chilli crop vis a vis maitain optimum moisture level in soil during whole growing period of crop.

  • Can anyone help me to find out the k & a values (for Mark–Houwink equation) of an alternate co-polymer of maleic acid -sodium salt & di-isobutylene?

    Can anyone help me to find out the k & a values (for Mark–Houwink equation) of an alternate co-polymer of maleic acid -sodium salt & di-isobutylene (DIBMA-Na) in 1:1 methanol:0.1N Na2SO4 solution at 25oC or 30oC?

    Rituparna Kakati · Indofil Industries Limited

    Thnkn you Mr. Ahmed Mahmoud. I will go through the same & revert you back. I have already gone through Brandrup book, but could not find the required one.

  • What if molar is mesial out? Is it called mesial offset or distal offset?
    I used to call a molar that is mesial out as mesial offset but in many manufacturer catalogs tubes to accomplish such movements are called distal offset tubes.
    Haris Khan · Sharif Medical City

    Thanks a lot . This is indeed a  very logical answer. 

  • Could the concentration affect the specificity of antibody for intracellular staining in flow cytometry?

    The majority of antibodies for flow cytometry are recommended to use in a concentration specifically for 1,000,000 cells, só what happens if I use 200,000 rather than 1,000,000 cells. Could it affect the specificity of monoclonal antibodies? or they are just eliminated in the wash steps.

    Luis Alberto Sánchez Vargas · University of Veracruz

    Thank for your answer Justin

    I'll titrate the antibody. Well, I used the antibody at high concentration that usually need to be, so I found positive cells, but I did not know whether these were specifically to the target that I was looking for. I'm according to you, thanks.

  • Can we use positive sequence current/voltage component to discriminate different types of faults in transmission line?
    I have to use this concept in relay design. how we can use it?
    Samim Gambhava · Pandit Deen Dayal Petroleum University

    Thank you for your valuable answer.

    I want to know that Negative sequence component use for only fault detection in transmission line or required all sequence component for only fault detection not for discrimination. HOW? 

  • How can I find the thermal conductivity of a copper sample of 8 mm dia. and 3 mm height?

    We have a HotDisk TPS 2500 instrument with us, but since copper is a highly conductive material the sample size needs to be larger, which cannot be made in our case due to material constraints. Pl. suggest some economical alternative for measuring thermal conductivity precicely. Is it possible to get a precise thermal conductivity value from electrical conductivity?

    Alain Celzard · University of Lorraine

    Thank you Jean-Georges for helpful comments. Now I clearly inderstand what you did, and why. Elegant work.


  • How to preserve thermophilic organisms?

    I had preserved my thermophilic organisms by preparing glycerol stocks but everytime when i am reviving it they are not growing again on plates ...please suggest some methods

    Sarabjeet kour Sudan · Institute of Microbial Technology

    thank you so much sir for your guidance ....sir i did this and found growth in liquid medium but when from that media i tried to grew these organisms on plate then there was no growth on plate.....

  • Naveen Bhatt asked a question in Steam Turbine:
    Use of yield strength in creep zone?

    I was going through some literature on AUSC steam turbine (operating temperature 700 deg C). In many of the papers i have seen that 400 MPa yield strength at operating temperature was used as material selection criteria for turbine rotor. At the same time some people are using Alloy 617 for same application, for which creep rupture is quite high (around 137MPa at 700 deg C) at operating temperature but yield strength is around 200 MPa.

    Can someone please explain how higher yield strength at operating temperature (creep regime) is advantageous also if for two material all properties are same (including ductility and toughness also) and there is difference only in their yield strength, against which failure mode this higher YS will be advantageous. What is the basis of 400 MPa YS at operating temperature?

  • Ankit Kansara added an answer in Elastomers:
    What techniques are suitable for determining cross-linking density in a polymer?

    We have some O-rings made of perfluoroelastomer (FFKM) from a different vendors and we would like to determine the cross-linking density to correlate with performance. Can anyone suggest a suitable technique?

    Ankit Kansara · Central Salt and Marine Chemicals Research Institute

    Swelling degree measurement is the best way to determine the cross-linking density of polymer using Flory-Huggins theory.

  • Hoang Son asked a question in Vietnam:
    Unidentified plant from Vietnam

    Unidentified plant from Vietnam: Can anyone help?

  • Aditya Menon asked a question in Cancer Cell Line:
    How to confirm whether a cell line is MCF7??

    I am working with a cancerous cell line and i want to confirm whether it is MCF7.  Is there any method to do it?? Is there any biological marker which i can look for conformation?

  • Kartinee Kassim added an answer in Phytochemicals:
    For best yield, what is the best method for preparing an aqueous, methanolic and ethanolic fraction from the leaf?

    Phytochemical extraction yield.

    Kartinee Kassim · Putra University, Malaysia

    Sequential extraction using solvents of different polarity starting from non polar to polar solvents. Good luck

  • Is Keynesian theory back?
    Have developed countries implemented Keynesian policies to counter the Great Recession? If yes, to what extent and where? If not, why not? Are governments stuck in the current policy mix?
    I am trying not to prejudge either way. Perhaps the optimal policy would be more politically unfeasible austerity? Or instead, an unprecedented, but politically unfeasible, increase in the scope and role of the government?
    Pablo Klein-Bernard · Instituto Tecnológico Autónomo de México (ITAM)

    Sorry if I am replying to myself and resurrecting my dead thread, but I would like to post an update to this topic:

    -- I read Jonas Pontusson and Damian Raess "The Politics of Economic Crisis in Historical-Comparative Perspective", and this made me think that the answer depends on what one considers to be Keynesian Policies (KP), or what brand of KP is applied.

    If you consider KP to be fiscal stymulus packages in the form of public deficits then yes-- the fiscal stymuli as % of GDP (including "autometic stabilizers")-- according to op.cit.-- amounted to 8.4% in the US, 8.3% in the UK, 4.9% in France and 4.3% in Germany. But those deficits were in large measure applied to bailing out the financial industry, which averted a significantly worse outcome, but did not restore sustained economic growth, mostly (and this is my opinion) because households perceive the world as a much darker place than before: many jobs have disappeared, some have returned but they feel precarious, and the future capability of governments to provide a decent safety net is no longer granted.

    Buy I tend to think about old fashioned Keynesianism as governments taking an active role in the economy by carrying out huge infrastructure projects, expanding public services and hiring a large number of unemployed as teachers, bus drivers, engineers, researchers, road builders,.... Well this did not seem to happen, because of todays constraints (?) and also because  those policies have been unfashionable for a very long time.

    Although it's interesting to note that one of the recently announced pillars of "draghinomics" mentions starting eurozone-wide infrastructure projects to ease the pain of structural reforms. Then, perhaps, the policy discourse is starting to shift...

    Any thoughts on this?

  • William Mayor added an answer in Genesis:
    When were the Creation accounts in Genesis 1 & 2 composed, and who by?

    I am reading Mark Smith's "The Priestly Vision of Genesis 1" (2010) and finding it very frustrating.  He is so convinced that P wrote the account in the 6th century he doesn't bother to tell us why he is so sure.  I am not much disposed to believe in P, J  JE, RJE etc etc considering the fiasco that is the story of Q.  What is the evidence?  Note that I say "composed",  not "written"?  One issue is the canonical text and its editor.  Another issue is the set of sources the editor used.  A third issue of great importance is how the editor used his sources,  and what creative freedom he allowed himself.

    Chris, I tend to believe that the gospel writers, just as the original writer of the Genesis accounts, did want us to see what they saw.  However, they also wanted to make certain that we saw it the way they wished us to see it.  They were not modern journalists, but rather people of their age.  The exact details were not as important as the overall message, and even more than some of the spin doctors of today (both liberal and conservative), either ignoring or embellishing points was acceptable practice to ensure that the desired message was delivered. 

  • Rakesh Kumar Tekade added an answer in siRNA:
    What is the best way to determine the entrapment efficiency of siRNA loaded nanoparticles?

    I am basically wondering how I can determine how much siRNA has been loaded in nanoparticles after formulation. Can anyone suggest the best or simplest method?

    Please suggest. Thank you.

    Rakesh Kumar Tekade · University of Texas Southwestern Medical Center

    Thank you Mr. Youssef Wahib. It really helped much! Kind regards


  • What are the factors that affect efficiency of targeted drug delivery using nano-magnetic particles?

    There are a large numbers of papers published on TDD involving nanomagnetic particles. Only few deals with in vivo or in vitro simulation. There are a number of parameters involved in this technique. What are main criteria for these parameters?

    Rakesh Kumar Tekade · University of Texas Southwestern Medical Center

    Dear Dr. Mehta,

    It is a very important question to be addressed before designing targeted nanoparticles. As you asked for magnetic nanoparticles following points will be much critical:

    1. Particle size: To big or too small of nanoparyicle impose either excretion of scavenging through macrophagic system of the body, hence, over rides their action before they reach site of action.

    2. Zeta potentiaal: It is a long debated point, and to be precise for a nanoparticle to be able to be free from any protein adsorption in the blood, it must contain slight negative charge, because positive charge NP adsorbs negative charged blood proteins.

    3. Circulation time is very crucial time: usually researchers tries to enhance it through PEGylation

    4. Stability is offcourse very imp, and they sd be ableto retain size during storage, as well as after application in physiological system.

  • Rajesh K. Parsapur added an answer in Crystallinity:
    Why did my strategy to prepare mesoporous Zeolite using quaternary ammoniums with long tails (C12)4N+ fail?

    Why did my strategy to prepare mesoporous Zeolite using quaternary ammoniums with long tails (C12)4N+ fail and why  did multi quaternary surfactants sucede? 

    As it is clear, zeolites can be synthesized with or without using organic templates. Before a decade ago it was a herculean task to induce ordered mesoporosity in zeolites. Crystallinity wasn't observed at meso level by increasing the chain length or template or by using gemini surfactants. Whereas now, multi quaternary ammonium surfactants are able to produce crystallinity at both meso and micro levels. What is the factor that was forbidden in the former strategies and is now aiding these new surfactants. Can I forethink mesoporous zeolite synthesis without involvement of organic templates ?

    Rajesh K. Parsapur · Indian Institute of Technology Madras

    Thank you sir, high ammonium concentrations (multiquaternary ammonium ions) will accomplish the task. Its established and extensive research is going on these hierarchical zeolites. but to meet industrial demands, ain't sure these structures meet the challenges since this synthesis end up in to 2D hexagonal porous materials which have diffusion limits and also less orderedness. I want to induce true mesoporosity/ hierarchy (eg: germanosilicate ITQ-43)  by using SDAs (zeolite templating) instead of supramolecular templating.

  • Amaury Lendasse added an answer in ARIMA:
    Can I use an ARIMA model to approximate a stationary time series?

    I know ARIMA is a model used for non-stationarity, but I want to know what will happen if I used it for a stationary sequence. 

    Amaury Lendasse · University of Iowa

    In general you can try these model successively:
    - AR (to have a baseline model)
    - ARMA (should work in your case)
    - ARIMA
    - NAR (nonlinear AR)

  • Saptarshi Roy added an answer in PSCAD:
    How to do switching in PSCAD?
    Saptarshi Roy · National Institute of Technology, Warangal

    You can use solid state switches....

  • What is the role of a vector meson rho in marking a Gamma gamma event in a particle physics?

    Hi all,

    I wanted a detailed explanation of why Rho meson is so very important in marking a Gamma gamma event.Or it would be great if someone could suggest me some papers related to this topic.

    Swathi Sasikumar · Deutsches Elektronen-Synchrotron

    Thank you Garth for such a good answer. :)

  • Jay Kant Yadav added an answer in Neurotoxicity:
    Can someone suggest an appropriate neuronal cell line for studying the amyloid mediated neurotoxicity?

    We are working with several amyloidogenic peptides and world like to investigate their neurotoxic effect.  

    Jay Kant Yadav · The Central University of Rajasthan

    Dear Aseem, Many thanks for the information.

  • Paul R. Yarnold added an answer in Statistics:
    Statistic analyses on vegetasi

    What is the statistic analyses that I can use with unbalace design study if I want to see the vegetation abundance relationship with envirimental parameters?

    Paul R. Yarnold · Optimal Data Analysis LLC

    Hi Evi, thank you for answering my query. I would recommend using a two-stage analysis, with each analysis treating mine rehabilitation versus natural woodland as the class variable. In the first stage, UniODA would be used to assess the relationship between each of the individual variables (ordination as well as environmental parameters) and the class variable. In the second stage, CTA would be used to identify the best subset of variables to differentiate the class variable categories. 

    For a discussion of UniODA see:

    1) Yarnold, P.R., & Soltysik, R.C. Optimal data analysis: Guidebook with software for Windows. Washington, D.C.: APA Books, 2005.

    2) http://odajournal.com/2013/09/19/optimal-data-analysis-a-general-statistical-analysis-paradigm/ 

    For a discussion of CTA see: http://odajournal.com/2013/09/19/62/

    For a discussion comparing parametric and maximum-accuracy ODA methods see: https://www.researchgate.net/post/Is_anyone_familiar_with_full_factorial_design

    If you try these analyses and have any questions, please contact me and I will be happy to lend a hand if I am able.

  • Does anyone know of studies on the concept of Infinite from an anthropological point of view?

    Metaphysical conceptions of the Infinite in particular cultures or in a cross-cultural perspective; interdisciplinary studies on this theme, between Philosophy and Cultural Anthropology.

    Vikram Zaveri · Independent Researcher

    Infinity and zero are relative terms and mathematically inverse of each other. Therefore from my point view one does not make any sense without the other. Similarly there is no such thing as absolute zero or absolute infinity. You can say that zero is an infinitely small quantity or infinity is some very very large quantity. In Advaita Vedanta philosophy, there is a concept of formless God, which is the underlying reality of the entire universe and is called Brahm(a). But this Brahm is not described as infinite. It is described as one without a second. The word Advaita means non-dual. Advaita is a state of mind of the person who has reached perfection and acquired immediate knowledge of Brahm. In this state of mind the individuality of the mind gets dissolved in Brahm and the distinction between the observer and the observed gets lost. This is
    when the perfected man is able to say "I and my father in heaven are one.' Or "Those who have seen me has seen the father." Therefore the concept of one without a second is more realistic and accurate compared to infinite.