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  • Amierul Sharudin added an answer in HUVEC:
    Where can I get a detailed explanation on the population doubling level (PDL) by HUVECs?

    How do you calculate PDL? I need some expertise on this issue along with journal or article regarding population doubling for huvecs.

    Amierul Sharudin · Ministry of Health Malaysia

    Tq everyone.

    does the calculation start after thawing the cell or after first subculture/ passage

  • Anurag Mishra added an answer in Cloud Computing:
    How can I implement security in cloud computing ?

    i have installed cloudsim but i dont know how to implement security in cloud computing . also suggest me if i can use other simulator . please help...

    Anurag Mishra · ABV-Indian Institute of Information Technology and Management Gwalior

    Security in software level .. i want confidentiality and sign that with digital signature .. and sent to the cloud where cloud check integrity of data and vice versa

  • What is the best way to calculate the size distribution of nanoparticles ?

    What characterization technique could be the best in that case for instance  we can do the mappping using TEM also. Is there any simulation software to show the size distribution and represent the structure of distribution of particles in the matrix they are embedded in ?

    Purnimaa Sasikumar · Sir M. Visvesvaraya Insititute of Technology

    Thank you Mr Saeideh it was very useful to me as well :)

  • I have 2x2 nonparametric set of data to be tested. What should I do?

    I have a two groups of test subjects, and pre and post data of each group. I was told that I should use nonparametric equivalent of two ways repeated measured anova. However, I could not find what it is. The number of subject is fairly small, 20 for the experimental and 24 for the control. I know that it is difficult to look for interaction in nonparametric data, but is there a way to test my data? 

    Thank you


    Kun il Kim 

    Ronán Michael Conroy · Royal College of Surgeons in Ireland

    Don't get worked up over normality tests. They are over-sensitive, while regression procedures are pretty robust. 

    Here is some advice from a much more qualified expert than I:

    “If a deviation from normality cannot be spotted by eye on [a normal quantile plot], it is not worth worrying about. I never use the Kolmogorov–Smirnov test (or one of its cousins) or the Chi-squared test as a preliminary test of normality. They do not tell you how the sample is differing from normality, and I have a feeling they are more likely to detect irregularities in the middle of the distribution than in the tails” (Miller 1997, 13–14).

    Miller, R. G., Jr. 1997.
    Beyond ANOVA: Basics of Applied Statistics.
    London: Chapman & Hall.

    I've attached normal quantile probability plots of the variables. They don't look half bad. I'm on a lunch break on a stats course I'm giving out in Penang, but I'll have a look at the model if I can later. 

  • Sandip Pchoudhury asked a question in Co-authorship:
    Co-Authorship for providing me facility (Humble request)?

    I am interested to work on gas sensing but my institute doesn't have the setup? If any1 has a setup in his/her lab, can I get an opportunity to work there? If I am able to bring out a substantial paper out of the work I will include the names of the persons involved in my paper as a co-author.

  • What is origin of oscillatory heat signal in ITC experiment?

    In Isothermal Titration calorimetry experiment shows kind of oscillatory heat signal i.e, each injection shows both exo and endothermic peak even for heat of dilution experiment. This oscillation keeps on increasing with the number of injection. Can anyone please tell me what could be the reason for this. (ITC cell contains protein solution, syringe contains just buffer)

  • What is the suitable method to perform calcium flux studies using confocal microscopy?

    I want to perform calcium flux studies of my formulation on breast cancer cell lines. I found few fluorometric method to achieve it. But I am much more concern to do analysis using Confocal microscopic method.

    Jaykumar Kambli · Advanced Centre for Treatment, Research and Education in Cancer

    Thank you Just Genius.

    I have not planned for quantitative measurement  of  calcium. I may think of after getting initial results. Thanks for guidance.

  • Does anyone here know the total number of sea urchin species worldwide and corresponding author?

    I am searching for a reference on sea urchin population biology and ecology, including the number of species and exploitation status. 

    Rodulf Anthony Balisco · Western Philippines University

    Thanks for answering guys! I know it will be helpful. I am currently working on Tripneustes gratilla in one of the contested islands in Spratlys in South China/West Philippines Sea. I want to determine the number of sea urchin species worldwide and the number of commercially-important species.

  • Rajat B added an answer in Atoms:
    What is the significance of center of charge?

    If the center of charge (where the dipole moment is zero) lies closer to a specific atom (lets say X) of an electronically charged molecule (anion or cation), will it signify that the charge (or electron density) is accumulated (or diminished) near atom X?

    Rajat B · National Physical Laboratory - India

    consider a see-saw balanced by two children sitting on either side of it and a ball[center of mass] is placed in the center of the see-saw. Now when the weight on anyone side is increased the ball also goes in that direction. This is classical. In quantum it might be opposite. Hence the charge is less near atom x. Please correct me if I am wrong. 

  • Harikrishnan cl asked a question in Metal Forming:
    How to carry out a dynamic explicit analysis in ABAQUS?

    while carrying out a dynamic explicit analysis in ABAQUS for a metal forming process,I encountered a problem while defining Boundary condition.the following message popped up:"In dynamic explicit analysis how the following error  message can be countered.the process is related to metal forming. "In an explicit analysis step, an amplitude must be referenced if nonzero displacements are specified"

  • I Putu Susila added an answer in Contiki:
    How do you broadcast a message/command in Contiki?


    I just want to broadcast a message to a number of nodes, using Contiki socket.

    I Putu Susila · Badan Tenaga Nuklir Nasional


    you can broadcast a message with Rime stack. There are examples in the repository https://github.com/contiki-os/contiki/tree/master/examples/rime

    Or you can use publisher/subscriber model with MQTT protocol (http://mqtt.org/) . In this case, a broker like mosquitto need to be installed and available in the network. In the device side, use mqtt client library for publishing/subscribing message. One example is http://hacks.esar.org.uk/contiki-mqtt-client/ One advantage using mqtt is you will be able to broadcast a message to a variety of clients (no need to be a 'contiki device').

  • Jiyu Sun asked a question in Nanoindentation:
    What is the relationship of storage modulus and young's modulus?

    I am working on dynamic nanoindentation test, and i wonder the relationship of storage modulus and young's modulus?

  • Daisy Konwar asked a question in Sustainability:
    Is there any other economically viable alternative to 'Maximum sustainable yield' for analyzing economic sustainability of fishery resources?

    For its complexity and unavailability of required data (for each and every species in concern) MSY is a tough nut to crack.

  • Lakshmana Reddy added an answer in Plant Genomics:
    Why am I seeing double bands?

    I am genotyping a group of TDNA insertional knockout plants using a triple primer mix (Gene specific primer set and the LB primer). Attached is an image of the resulting DNA gel and as you can see plants 4, 10 & 11 are wild type (WT). What I don't understand is why every other plant (1-3, 5-9, & 12) is showing two prominent bands around 1kb. At first I thought they were heterozygous for the insertion but neither of the bands match up with what is seen in the WT lane.

    Any suggestions?

    Lakshmana Reddy · Indian Institute of Horticultural Research

    The three primers loci may be in heterozygous condition, because SSRs are co- dominant in nature, but the size difference between  two bands normally in few base pairs  

  • Rambir Singh added an answer in Smart Grid:
    How can I add an additional port to a 3 phase V-I measurement block?

    I am using this block in matlab/simulink software but it has only two ports for voltage and current but I need a third one for power. Any idea how I can do this

    Rambir Singh · Inderprastha Engineering College, Ghaziabad

    Right click the block and select look under mask. add another output port  by modifying the block. using a product block take input from voltage and current output ports, rename the new port as Pabc.

  • Encoding skyscrapers: Is there an influence of culture on the architectural imagery?

    I am currently working on my thesis topic on how the culture influence on the architectural imagery of skyscrapers. Do you have any recommended sources I could use and what is your opinion on the topic and area I have chosen?

    Danushka De Silva · Deakin University

    Thank you Stephen for the valuable information. Surely it will be a helpful answer for my thesis. Cheers mate!!!

  • Shivaprasad S added an answer in CPU:
    How to utilize 2 processors of workstation simultaneously for a single COMSOL simulation?

    I have a workstation with dual xeon processor with 64 GB RAM. I have installed COMSOL Multiphysics as per the Installation Guide. But when I checked the CPU usage, I found that only one of the processors is utilized per simulation. The other one is unutilized. When I run the second application, it uses the other processor. So when we run 2 or many COMSOL Simulations - Its ok that the CPU is utilized properly. As my simulation is a bit heavier, I need to use both the processors simultaneously for a single application. What settings should be made to do this?

    Shivaprasad S · Indian Institute of Technology Madras

    In Preferences, go to multicore and cluster computing option, Tick the number of processors option.(Version Comsol 4.4)

    By default if will show the maximum number processors you have, you can limit them by entering the number of processors you would like to utilize.

  • David Lim added an answer in Basic Amino Acids:
    Why Positive charge on "basic R group of amino acid"?

    My textbook shows that all the acidic amino acids are negatively charged and all the basic amino acids are positively charged. I would think it should be the reverse. Shouldn't a negatively charged amino acid attract protons, hence decomposing water, increasing the hydroxide concentration and therefore forming a basic solution?

    David Lim · University of Canterbury

    Textbooks most often illustrate amino acids in their charged states at pH 7 (physiological pH). The charged state of the amine and carboxylic acid functionalities on amino acids depends on the pH of the solution, which in turn is related to the functional groups' pKa (-log Ka). Very simply put, when the pH of the solution is above the pKa, the group will be in its deprotonated state. Conversely, when the pH of the solution is below the pKa, the group will be in its protonated state. As a rule of thumb, carboxylic acids have pKa's of ~5 and amines have pKa's of ~10. Therefore, at pH 7, amines will be protonated (NH3+) and carboxylic acids will be deprotonated (COO-). To extend this principle further, if you raise the pH to 12, both the carboxylic acid and the amine will be deprotonated (i.e. NH2 and COO-) and if you lower the pH to 3, then both the carboxylic acid and amine will be protonated (i.e. NH3+ and COOH). Your comment about the carboxylate (COO-) deprotonating water can also be addressed using pKa values. If you want to deprotonate something with an x pKa value, you'll need to use a base that has a pKa which is higher than x. While a carboxylate can act as a base, water has a pKa of 15.6, so there's no way a carboxylate will deprotonate water.  Hope that helps.

  • Rajat B added an answer in Coating:
    What is the reaction temperature of HCl and FeAl alloy?

    Dear all, I'm using pack cemetation method to apply aluminide coating on surface of the alloy with activator NH4Cl, but the presure of the chamber is not very stable above 800C, so I want to know at what temperature , the HCl react dramatically with FeAl alloy.

    Thanks for your help

    Rajat B · National Physical Laboratory - India

    FeAl alloys had good strength at 700-750{degrees}C[1]. So maybe a temperature above that. I read it is sintered at 1100degrees celcius[2]. Also there is a paper [3] which tells about reaction of HCl with FeAl alloy. Hope these sources and info helps you.

    1. worldwidescience.org/topicpages/b/b2+feal+alloys.html

    2. espace.library.uq.edu.au/view/UQ:198591

    3. www.journalamme.org/papers_amme06/1219.pdf

  • Swati Mohapatra added an answer in Biotechnology:
    Which type of the sport exercises have the most positive effect on creativity of our brain in the research?

    As researchers (and no matter in which field: optics, engineering, physics, mathematics, biology, medicine, biotechnology and etc.), many of us are most of the time dealing with research work, and often forget that there is also a life outside the university. But our efficiency decreases with the time and good ideas are not born. 

    If we are willing to allocate an hour a day or an hour in a few days for sport, which sport will improve the creativity of our brain in the research?

    Swati Mohapatra · Centre for Cellular and Molecular Biology

    I think it's totally depends on the person (personalise) because Every one don't like one type of game, The game which you like to play that give relax to you mind may be a pressure to him or her. so any game that you enjoy will be better to increase efficiency and will give good ideas.

    But swimming is a best exercise for our body which is beneficial also. 

  • A. Saravanan added an answer in Analytical Methods:
    Is it necessary to discuss the stability even if the analytical solution of a PDE is available?

    I have used an analytical method to solve nonlinear fractional PDE and it gives the series solution.  Is it necessary to check the stability even if the analytical solution is available? 

    A. Saravanan · Sona College of Technology

    Thank you so much sir.

  • Sunday Asakpa added an answer in Image Compression:
    Can someone tell me the best or most efficient image compression algorithm for encryption?

    Visual cryptography

    Sunday Asakpa · Federal University of Technology, Akure

    Thanks everybody for your suggestions

  • How can I download Georient Software and install it?

    In my PC, when I go to install it, a note is coming "Run time error 339" and "Component THREE32.OCX or one of its dependencies not correctly registered" 

    Please provide me usefull techniques to solve this problem.

    Suvendu Roy · University of Kalyani

    Respected Aher Sir, 

    I already downloaded from that site but there is problem related to files, which is already stated in my question.

    If possible, please send the original version of full software via e-mail, 

    Thank you. 

  • Vaishali Sharma asked a question in References:
    What is difference between F3 and F2:3( read F2 derived F3) population?

    Kindly provide a suitable answer and If possible a reference paper for that so that I can refer it in future.

  • Razia Adam added an answer in Crowns:
    Would you recommend crowns for high caries risk patients?

    It has become clear to me that the indication to place a crown or inlay restoration rather then a direct composite (or amalgam) restoration is not based on sufficient scientific evidence. As a result, especially among different countries great differences in treatment choices may exist.

    Therefore: would anyone make a crown in a caries risk patient in case of a large defect where the alternative would be a large, probably deep subgingival restoration.

    In the Netherlands we tend not to do that as we only place indirect restorations in patients with a stable mouth condition (low caries risk). I know that in other countries that may be different. So please tell me what is the indication for crowns in risk patients in your university or practice.

    Razia Adam · University of the Western Cape

    Dear Niek,

    In my experience in a university setting,  it is advocated that the patient has a good oral hygiene and that all caries is controlled in the mouth prior to commencing with 'advanced restorative dentistry'.

    However, having said that it is a reality that in most dental practices, no  formal caries risk assessment is completed .A number of factors would play a role in the final decision-making and it would be interesting to have a global comparison .

  • How to 'Plot over line' in openFoam and vector plot by another software?

    Dear Foamers!

    This question is the continuation of my simulation works, which I have posted earlier time [link attached]. Based on suggestion from my previous asking question, I am investigating mesh grading and checking the result. Please have a look at the attached image. In paraFoam, using plot over line filter, I have tried to plot velocity profile in diffuser section. Contour plot showed reversal flow (negative velocity) but the velocity profile showed only positive velocity. From the plot, it is clear that left vertical axis represent velocity and what is about bottom horizontal axis? Is it wind tunnel height?

    In the result file which were stored based on time step, I have opened U file of last time steps. The file contains 3 column of vector data for velocity. As this file represent vector information, so it contains Ux and Uy information. Can anybody tell me the details of these 3 columns ?

    Full resolution: http://i62.tinypic.com/vnm8n4.jpg



  • Kai F. Albring added an answer in Western Blot:
    What WB blocking agents are there which do NOT contain dry milk or BSA?


    I have an antibody which could not be used with blocking agents such as dry milk or BSA. What would you recommend for blocking? Please help me, as soon as possible :)

    And commercial ones are excluded...

    Kai F. Albring · Friedrich-Schiller-University Jena

    Hi Laura,

    if you are working with PVDF membranes I would recommend an over night block simply with TBS+ 0,1% Tween20. It worked well for me in >90% of antibodies I have used (except phospho-specific).


  • Sujitha k Anandarun asked a question in Tocopherols:
    Alternative for ascorbic acid?

    Ascorbic acid is used as a standard in reducing power assay. alternative to ascorbic acid BHT, BHA, Quercitin, Tocopherol are used as a standard, other than this is there any alternative standard can be used for ascorbic acid, for analysing the antioxidant activity for venom protein

  • How can Scientists and researchers measure Insecticide resistance in insect field populations directly?

     The assessment of insecticides efficiency and monitoring insecticides resistance in insect field strains is very important to Scientists and Researchers

    Farhanullah Khan · University of Karachi

    The method, told in the last para by dr.Grant A Herron, is some what similar to that of the method described by the WHO for the insecticide susceptibility test with pre treated insecticide impregnated papers. Collected Insects are exposed into a jar/cylinder already got inserted an impregnated paper with known % of insecticide; results are comparable with the previous data of the unexposed susceptible population.

  • Sujitha k Anandarun asked a question in Venoms:
    Venom protein has antioxidant activity?

    Does anyone worked on venom protein that possess antioxidant activity, only marine sea weeds and some algae and plants has more antioxidant activity, but the venom of an animal had these antioxidant activity.