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  • Suseel Jai Krishnan added an answer in Uncertainty Analysis:
    Can anyone please explain on how to do an uncertainty analysis while determining pressure drop and heat transfer coefficient?

    It is needed for nanofluid flow in pipes

    Suseel Jai Krishnan · SA Engineering College

    Thank you sir

  • Thong nguyen quang do added an answer in Ranking:
    What is the number of characteristic subgroups of an abelian p-group of rank 2 ?

    What is  the number of characteristic subgroups of an abelian p-group of rank 2 ?Somebody asked this recently, but unfortunately his question seems to have  disappeared from the list of recent questions. If he's still interested in an answer, please let him ask again

    Thong nguyen quang do · University of Franche-Comté

    See my answer to Amit Sehgal

  • Partha Pratim Dhar added an answer in Sesbania:
    is this Sesbania bispinosa?

     I think it is Sesbania bispinosa but I need your opinions.

    Partha Pratim Dhar · King Saud University

    Natchimuthu Karmegam is right. It is S. bispinosa. Black spots are present on the petals of flower. So it is S. bispinosa.

  • Kishan Rao Kalitkar added an answer in 5G:
    Will 5G be cheaper compared 4G ?

    Will the 5G mobile users have to pay less tariff compared to 4G ?

    We know that 5G offers 100 times higher data rates. Spectrum will be cheaper since it is moving to higher frequency range including millimeter wave band. This should help to drop the costs to 100 times.

    Will it be feasible ?

    Kishan Rao Kalitkar · Vaagdevi College of Engineering

    we expect the cost of tariff of 5G will be same as 4G in course of time.

  • Mary C R Wilson added an answer in Welfare State:
    Is there any on-going research into the social impact of reduced funding for UK local authorities, and their services?

    I am a researcher in the housing association sector, and we are currently keen to identify the impact that housing associations have when they 'step into the breach' created by local authorities reducing services and investment.  Knowing of any research that is currently on-going would be helpful as a starting point.  Many thanks. Marcus

    Mary C R Wilson

    Hello Marcus

    There were many reports and recently published books (that possibly did not have such recent contents), but less recent research, and not particularly ongoing.

    This is a research report (both summary and full report) that may be of interest (a Joseph Rowntree site):

    The impact of welfare reform on social landlords and tenants, Anne Power et al., 23 June 2014


    This site (see table) lists further Joseph Rowntree research, and other research projects:


    This is from the Institute of Public Policy Research (also funded by Joseph Rowntree):

     Build now or pay later: Funding new housing supply, Andy Hull, Graeme Cooke and Tony Dolphin, October 2011


    This is from local government, Dec 2014: A report of research carried out by the Cambridge Centre for Housing and Planning Research (CCHPR) on behalf of the Department for Work and Pensions.


    Supporting households affected by the Benefit Cap: Impact on Local Authorities, local services and social landlords


    Are these relevant to your question? This is not research but discussion:

    Hodkinson, S., & Robbins, G. (2013). The return of class war conservatism? Housing under the UK Coalition Government. Critical Social Policy, 33(1), 57-77.


    This references various research projects:

    Chevin, D. (2013). Socially hearted, commercially minded-‐a report on tomorrow’s housing associations. The Smith Institute. Genesis, London.


    I have not been able to access the full text of this paper; it is not a research project but discusses research:

    Fitzpatrick, S., & Pawson, H. (2014). Ending security of tenure for social renters: Transitioning to ‘ambulance service’social housing?. Housing Studies, 29(5), 597-615.


    Is this site of any interest? It is research based, but I am aware that it might be known to you already?

    Without flexibility from government, further cuts to welfare funding will pressurise local authorities and risk rising levels of hardship, warns Grant Thornton research


    If you click at the bottom:


    not only can you access the full report, but also other information.

    This is: 

    Easing the burden: The impact of welfare reform on local government and the social housing sector, May 2015


    Good luck with your project


  • Rami Elshazli asked a question in Logistic Regression:
    How can I adjust age and gender in spss using logstic regression?

    logistic regression

  • Hanno Krieger added an answer in Insects:
    Can anyone help me identify these insects in the following photos?

    Photos taken some days ago when doing training with my new camera. Please help me with the identification. I´m no entomologist. Thanks!

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    Thanks for the detailed analysis.

    Best regards Hanno

  • Hanno Krieger added an answer in Radioactivity:
    Is it dangerous for the staff, inpatients or outpatients at a hospital to care for radioactively contaminated patients or to be near them?

    researcher who has experience in radiation 

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    I´m not Aida, but in Germany we have eypecial stations, we call it "Abklinganalage", cooling plants where all the excrements and waste water are kept and measured before disposing by spectroscopy, especially the long lived nuclides like 131-I.

  • Ruiying Li asked a question in Alginate:
    How do I separate a polyelectrolyte complex made up of chitosan and alginate complex from a polymer?

    I am using chitosan and alginate to make nanoparticles, they are in 170 nm size range. Before further study, I want to separate them from free polymer. I have tried centrifuge, but it's hard to disperse them afterwards. Also, there are still nanoparticles in the supernatant, which means centrifuge didn't really separate them. Chitosan and alginate form nanoparticles by electrostatic interaction, it easily aggregate if the speed is too high. I thought about dialysis,but chitosan and alginate are huge molecules, didn't find any membrane is big enough for them to go through. Does anyone have any idea how I could separate them? Thanks a lot!

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub · University of Massachusetts Amherst


    What Kant says cannot be known in principle is a product of Kant's biologically limited brain. A better tool than most most of us have, but still with natural limitations. ; )

  • Asher Klatchko added an answer in Electrostatics:
    Could the fundamental dimension of Electric Charge be Mass only?

        After solving dimensions of electrical equations, I found out that the fundamental dimension of Electric charge is mass only. This also leads to the derivation of dimensions of other Electrical units like Electric Current, Magnetic flux density etc in terms of Mass, Length and Time only. These are not cgs units.
         This discovery can help unify the force of gravitation that uses mass and the electrostatic force(Force between charges).This will help contribute to the theory of everything, also in better understanding of the electrical units and equations. e.g Work done=Charge times Voltage. Substituting the right handside with their dimensions of Charge=Mass and Voltage=L^2T^-2 proves that the equation is dimensionally consistent. Also other theories can be uncovered and better understood with this finding.
         I wish to be challenged if possible and I will show the steps of the derivation.

    Asher Klatchko · Reed College

    what if the constants h≠c≠1

  • Dorothy C Bennett added an answer in Soft Agar Assay:
    Why are NIH 3T3 cells growing on the bottom in a soft agar transformation assay ?

    I start soft agar transformation assay using NIH 3T3 cells. These cells shall not form any colonies in soft agar assay. In upper layer of agar these cells survived and start to proliferate (they have round shape). But I found these cells in growing numbers on the bottom of the wells (normal NIH 3T3 shape). I prepared agar layers the same day,  bottom agar (0,5%) layer ca. 2 hours before pouring upper layer agar (0,3%) with cells. Does anyone have experience if these cells can "sneak" or crawl from top layer to the bottom of the plate and proliferate there (on 6-well plate, under the layer of agar)?

    Dorothy C Bennett · St George's, University of London

    If you are sure that the cells really are on the bottom of the dish, then it may be that there is a problem with the bottom layer setting - even though you left it quite a while.  Does it seem firm before you add the top layer?    If not, maybe the agar is a bit old?  Try getting new agar?  Or you can increase the concentration a bit, some use 0.6%.   Or is the top layer too warm and melting or disturbing part of the bottom layer? 
    A few thoughts.

  • John M. Plumb added an answer in Atlantic Salmon:
    Do fry released Atlantic salmon behave as wild fish during smolting and downstream migration?

    I'm looking for studies that compare behavior and survival of fry released salmon with that of wild fish (and/or with hatchery released smolt/parr), especially during the smolt stage. 

    John M. Plumb · United States Geological Survey

    Daniel, perhaps Peake's 1997 TAFS 126:707-714, may interest you, also check out my paper on smolting juvenile steelhead during migration, they have a similar life history to Atlantics. See my RG page - Plumb et al 2006 NAJFM 26:438-452.



  • Sivanandam Kaliannan added an answer in VLSI Design:
    In low power VLSI design, will clock gating technique reduce power all time?

    In low power VLSI design clock gating technique will reduce power all time or it depends upon the input date? Is any chance, the computation power may increase?

    Sivanandam Kaliannan · K. S. Rangasamy College of Technology

    Thanks Shivalal Patro

  • Chad D. Touchberry added an answer in Accounting Software:
    Software or Freeware to manage expenses?

    I am looking for a better solution than excel for managing lab orders and more importantly, the associated finances across several different account numbers. I'd like to know what I am spending money on, when, with whom and a easy snapshot of total balances. Anyone have any suggestions?

    Chad D. Touchberry · The University of Memphis


    I understand double entry book keeping, t-accounts and journal entries. So I would say I am at least a 5.

  • Hossein Javadi added an answer in Elementary Particles:
    Do photons interact with gravitons?

    The graviton is a hypothetical elementary particle that mediates the force of gravitation in the framework of quantum field theory. If it exists, the graviton is expected to be massless and must be a spin-2 boson. The spin follows from the fact that the source of gravitation is the stress–energy tensor, a second-rank tensor. But by no means is it universally accepted.


    But there are many articles about the interaction between Photon and graviton or graviton-photon scattering.



    How can graviton's mystery be solved?  Should graviton be detectable or like photon (same as photoelectric effect) be able to explain the physical phenomena?

    Hossein Javadi · Islamic Azad University

    Dear Stam
    I agree with you. My dear friend Azzam had written; "The decrease in the speed of light as measured globally according to my theory and transformations is depending on time only, not on the space-time " seems he had separated time of space it this argument. So, I wanted to show that time and physical existence such as space are inseparable.

  • Sivanandam Kaliannan added an answer in Boolean Function:
    Is any software tool available for boolean function minimization?

    For Boolean function minimization, is any software tool available?I need to reduce Boolean function, which have more than five literals, also it should be all time minimum.

    Sivanandam Kaliannan · K. S. Rangasamy College of Technology

    Thanks Giuseppe Tumminelli

  • THOMAS H.W. Ziesemer added an answer in GMM:
    Can someone solve my doubts about panel data with unit roots?

    Hello all,

    I am estimating the impact of FDI on poverty with a few other controls based on a panel dataset of  n=17 and t =19 (I can expand N to 33 but then it has a lot of missing values). I tested for stationarity and poverty has unit root of order two whereas fdi of order one. The controls are also a mix of orders one and two. I am extremely confused about how to continue this analysis. I belive that cointegration tests require the order to be similar?

    Would you recommend using system (even if I expand n to 33) or is there some other method to deal with this? What kind of problems can system GMM impose? Kindly help!

    THOMAS H.W. Ziesemer · Maastricht University

    System gmm is for stationary variables. But for short series panel unit root tests have low  power. Also check whether the unit root result vanishes if you add regressors.If T is large enough think of fmols.

  • Anuroop Venkateswaran Venkatasubramani added an answer in T-Test:
    Minimum sample size for t-test??

    Hi all.. I have been quite confused with statistical tests.. I think my doubt is very preliminary but I am not sure.. I have two populations (treated and un-treated) each with n=3. I would like to know if t-test can be used for a small population? I have read in some websites that t-test was introduced for small sample size but some say you would need at least 20. I understand that for low sample size, the population would assumed to be normally distributed but would it be correct to convert them into log and then perform the t-test??

    Or would Mann Whitney be a better test for low sample size??? The problem I feel with U test is that it is based on ranks and doesn't consider standard deviation (based on what I understood). Also, I compare treated and non-treated samples and that treated samples will have higher values in most cases and so U and U critical would be 0 (since n1=3 and n2=3 and p=0.05*2 as I use one-tailed, Ucric = 0).

    I hope I have explained my question clearly. Please provide your suggestions. Thank you!!

    Anuroop Venkateswaran Venkatasubramani · University of Helsinki

    Hi Khalid.. Thanks for your reply.. I was able to get my answers from Stata software but it was a trial version.. I will download the Gpower and use it in the future.. Thanks for the suggestions and the documents on sample size calculation.. Thank you..

  • M. Safiuddin added an answer in Power System Control:
    How can I model the transfer function model of fuel cell?

    I am currently working in Fuel cell based power system, now for modelling the controller I need to model the transfer function model of the fuel cell first. Is there any documents available to model the same? If so please share with me.

    Thanks and Regards

    Junior Research Fellpow

    Motilal Nehru National Institute of Technology

    M. Safiuddin · University at Buffalo, The State University of New York

    Please send me your e-mail address so that I may send you a conference paper on modeling of Fuel Cells and microturbines.



  • Thomas Adejoh added an answer in Surgical Robotics:
    Where can I find Pneumoperitoneum CT scan during surgery?

    I'm an engineer working in a company based in Milan (Italy) that wants to realize a medical surgical robot. We want to simulate pneumoperitoneum in a simulated environmental to find the perfect size for our robot. Do someone know where to find images of pneumoperitoneum during surgery? Or some dimensional data? 
    Thank you in advance.

    Thomas Adejoh · Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria

    In  case  you  can't  get  your  desired images,  I  advise  that  you  do  an  attachment  in  a  hospital  theatre  (with  permission)  to  get  your  desired  images.

  • AJ Roberts added an answer in Lipofectamine:
    Issue growing up RCAS virus, cells start to die following superconfluence. Can someone help me?

    Hi there,

    I wondered if anybody could help me. I've been trying to grow up my RCAS virus (with my gene of interest), over a three week period following (Logan and Tabin et al., 1998). 

    I initially transfect chick embryonic fibroblast cells with lipofectamine LTX, and continue splitting my cells in 10cm dishes, until I finally have 16 x 10cm dishes. I wait for them to become superconfluent (in picture attached), and then change to low serum concentration and then to start to collect supernatent. 

    However, I started noticing cells detaching like in the picture attached. I must add, when I seeded the initial there were some regions more confluent than than others. Does anyone have any suggestions.

    Next time I'd like to change to low serum medium earlier when cells are confluent (rather than superconfluent) in case my inserted gene is driving them to proliferate more. And secondly, change to flasks rather than petri dishes to stop cells from aggregating. 

    Hope someone can help me,

    Best wishes,


    AJ Roberts · Rivendell Institute

    Hi, Vanessa.  You may want to consider changing your protocol according to the protocols found in these two resources: http://www.biomedcentral.com/content/supplementary/1749-8104-7-22-S2.pdf  AND   http://cshprotocols.cshlp.org/content/2014/11/pdb.prot077974.abstract  

    Hope this helps. Good luck.

  • Masoud Darbasi added an answer in Food Science:
    How can I control the transfer rate of antimicrobial or antioxidant part of film to foods?

    Hello to everyone

    I want to make an antimicrobial or antioxidant film and i want to control the transfer rate of these parts from film to food products. Which edible film is better to use for this purpose and by which changes can I control the transfer rate of antimicrobial or antioxidant part of this film to foods? or other ways to control this rate?   thanks for all of you

    Masoud Darbasi · University of Tehran

    Thanks I'm going to have a study about release

  • Maryam Dastoorpoor added an answer in Quality of Life:
    Could you please help me identifying the most relevant scales to measure quality of life (QoL)?

    We are planning to measure the QoL of entrepreneurs, particularly in the context of the tourism industry. Thank you!

    Maryam Dastoorpoor · Kerman University of Medical Sciences


  • Samsher Singh added an answer in Tuberculosis:
    How can I measure the concentration of TB drugs in organs of mice after chemotherapy? what is the ideal time after therapy to study concentration?

    I am studying efficacy of TB drugs to disseminate in  various organs after drug administration either orally or via IV route. Main aim is to study how much concentration actually reaches the organs after administration for prevention of pulmonary and extra pulmonary TB. Can anyone suggest some good protocols??

    Samsher Singh · Indian Institute of Integrative Medicine

    Measurement of serum level concentration would most suitable. As Cmax is described by maximum achievable concentration. It is part of Pharmacokinetics routine studies and could well be achieved by MS or HPLC in my opinion. 

  • Jean-Jacques Morcrette added an answer in Solar Radiation:
    What's wrong with ERA INTERIM (sensible and latent heat flux) ?

    Hi all,

    I'm using the ERA INTERIM dataset. I downloaded the data (H, LE and Rn) like below. I know this dataset is not the best.

    sshf Surface sensible heat flux [J m**-2]
    slhf Surface latent heat flux [J m**-2]
    ssr Surface net solar radiation [J m**-2]

    But when I view the content for my surprising the values are "strange", see below:

    -1 : Date Time Level Gridsize Miss : Minimum Mean Maximum : Parameter name
    1 : 1979-01-01 12:00:00 0 1089 0 : -2.6211e+06 -3.0388e+05 1.7202e+06 : sshf
    2 : 1979-01-01 12:00:00 0 1089 0 : -1.4553e+07 -2.9573e+06 8.1755e+05 : slhf
    3 : 1979-01-01 12:00:00 0 1089 0 : 7.1395e-11 2.1309e+06 9.5987e+06 : ssr
    4 : 1979-01-02 12:00:00 0 1089 0 : -2.8324e+06 -3.5041e+05 1.5127e+06 : sshf
    5 : 1979-01-02 12:00:00 0 1089 0 : -1.7608e+07 -3.0635e+06 3.9123e+05 : slhf
    6 : 1979-01-02 12:00:00 0 1089 0 : 7.1395e-11 2.2015e+06 9.8327e+06 : ssr

    The values are very strange. Does anyone can give some tips about the data?

    Thanks a lot,

    Guilherme Martins.

    Jean-Jacques Morcrette · European Center For Medium Range Weather Forecasts

    ssr+str should give you Rn.

  • Thomas Adejoh added an answer in Biomaterial Applications:
    Does anyone know of a bioresorbable material which would dissolve within a couple of days?

    I would like to identify a (or several) biomaterial candidate that would be able to dissolve within 24-48 hours in saline at 37°C, but would not require specific conditions for storage (e.g. temperature control or excessively low relative humidity)

    Thomas Adejoh · Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria

    Dear  Pierre,

    Is this  biodegradable  material to  be  used  in  a  human  tissue  or  for  laboratory  tasks?

  • Anoop Kumar Srivastava added an answer in Soil Analysis:
    Which is the most effective method of diagnosis of nutrient constraints in perennials?

    In perennial crops , identifying nutrient constraints is truly  a complex exercise. An entire range of diagnostic techniques are being used , starting from soil analysis , tissue analysis ( Using index plant parts ) , metallo-enzymes , deficiency symptoms as  morphological descriptors, juice analysis, trunk injection to floral analysis,  of late. None of them alone is sufficient  to identify the nutrient constraint precisely matching to field conditions. Every method has its own merits and demerits. With the result , it is  often questioned that the currently available methods of diagnosis of nutrient constraints , are more inclined to diagnosis for the next season , overlooking the problems in the current season  standing  crop . This kind of constraint in diagnosis is so rampant in perennial crops. I wanted to know from researchers across , how to solve this so complicated issue?.

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

    Infact it is other way round. The classificagip

  • Shirley O'Brien added an answer in Team Leader:
    Is it more credible to determine the type/style of leadership exhibited first in leadership studies?

    I am studying leader-member relation and trust. When researching leader-follower relations in work teams, the style of leadership (transactional, transformational etc.) exhibited is important. Will it not be better to find or deduce the type of leadership in that team/by that leader by research or to presuppose any specific style even if I consider culture and other factors?

    Shirley O'Brien · Eastern Kentucky University

    Another consideration comes from organizational cultural perspectives of Bolman & Deal's Four Frame Perspective.  All frames are important, but you may see different parts of teaming given the symbolic frame activities. Temporal elements of the organization may shape the teaming stages too.

  • Nikolaos D Andritsos added an answer in Functional Food:
    Are toxicity studies required for functional foods?

    we are developing a functional food , so would like to know whether sub- chronic toxicity study is required.

    Nikolaos D Andritsos · Athens Analysis Laboratories S.A.

    One of the basic steps you should follow during the development of a functional food is the assessment of safety and activity of the bioactive compounds confering the functional role to the food concerned. In that essence, it is necessary to study the potential sub-chronic toxicity of the compounds used and/or use any available publications to international scientific journals (SCI) in order to prove that safety aspect.