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  • Who knows the stacking fault energy of Magnesium WE43 alloy?

    This group of Mg alloys contain RE elements which decrease the SFE of the alloy.

    Masoud Moradjoo · University of Tehran

    Excellent question Adib. I  just know that SFE decreasing in mgnesium alloy by addition of RE element. J.P. Hadorn et reported that this increase is linear. 

  • What are the major limitations for the practice of marketing concept / orientation in developing economies?
    The prevalent oligopolies and monopolies in the marketplace of developing economies.

    Reliance on resources mobilised equitably from among members more and less external dependence; Shift of emphasis from maximising profitability to maximising service to members not inconsistent with economic viability; Making goods and services available at as reasonable as a price possible; Making surplus basically to add to reserves in so far
    as necessary for good performance and continuity; Shifting of basis for surplus/deficit sharing and participation in decision-making process to patronage; Of services and limiting capital for entailment of a pre-decided limit of interest

  • K. Sreenivas added an answer in Polyvinyl Alcohol:
    Can someone advise me how to perform preparation of nano polyvinyl alcohol?

    any method to preparation of nano polyvinyl alcohol?

    K. Sreenivas · University of Delhi

    Dear Amma Harmal

    I have come across two papers, just check if they have useful information for your desired preparation of nano poly vinyl alcohol.

    J Control Release. 1998 Dec 4;56(1-3):117-26.
    Poly(vinyl alcohol) nanoparticles prepared by freezing-thawing process for protein/peptide drug delivery.
    Authors: Li JK1, Wang N, Wu XS.

    Journal of Drug Delivery
    Volume 2011 (2011), Article ID 962743, 8 pages
    Research Article
    Preparation of a Nanoscaled Poly(vinyl alcohol)/Hydroxyapatite/DNA Complex Using High Hydrostatic Pressure Technology for In Vitro and In Vivo Gene Delivery
    Authors: Tsuyoshi Kimura,1,2 Yoichi Nibe,1 Seiichi Funamoto,1 Masahiro Okada,3 Tsutomu Furuzono,3 Tsutomu Ono,4 Hidekazu Yoshizawa,4 Toshiya Fujisato,5 Kwangwoo Nam,1,2 and Akio Kishida1,2

    K. Sreenivas

  • Heiko Philippin added an answer in Glaucoma:
    What is the "gold standard" for diagnosing glaucoma?

    I have conducted some searches but I have received conflicting information.

    Heiko Philippin · Kilimanjaro Christian Medical Centre

    If I would have to choose a single diagnostic procedure I would do indirect ophthalmoscopy of the optic nerve with a 66dpt lens. Next would be VF.

  • Steve Wang added an answer in Functional Morphology:
    Skull functional morphology, can anyone help me?

    I'm searching papers about functional morphology of mammals skull.

    Can anyone help me? Thanks Armando

    Steve Wang · CUNY Graduate Center

    that's a really broad (Class level) subject!

    care to narrow down some more specifics? :-)

    i can help you in Order Primates.

  • Boris Shapiro added an answer in Convex Analysis:
    Is it true, that next Jordan curve be a circle?

    Let C be closed Jordan curve in R 2 and for arbitrary circle L from property that intersection C ∩L contains 3 points follows, that C ∩L contains no less then 4 points. Is it true, that C also be a circle?

    Boris Shapiro · Stockholm University

     Dear Yurii, I am not sure I understood your question since the number of intersection points between any 2 closed curves in R^2 (counted with multiplicities) is even. Thus your condition is automatically satisfied. 

    Yours B.Shapiro

  • Kristin R. Carpenter added an answer in Steel:
    How can I determine CCT curve of a steel using dilatometric measurements?

    I have dilatometric measurements (change in length, time and temperature data) of a microalloyed steel and trying to get the CCT curve from it. 

    Kristin R. Carpenter · BlueScope Steel, Port Kembla, Australia

    Completing metallography on your samples will help in determining what phases are present at each cooling rate.

  • Kah Ee Fong added an answer in NIR:
    What is meant by 'second near-infrared window'?

    Is there 'First Near-Infrared window' ? 

    Kah Ee Fong · Nanyang Technological University

    Thanks Daniel, that solved my question :)

  • Venkatesha NJ added an answer in Esterification:
    How can the esterification of a primary alcohol can be done in presence of secondary and teritiary alcohols?

    a hetero cyclic compound with a hydroxy substituted alkyl chain , is the compound of interest.

    Venkatesha NJ · Bangalore Institute of Technology

    its better to use base catalysts, because if you use acid catalysts carbo cation stability has a role, instead if you use base catalyst carbanion as a role and primary is more stable.

  • What is the starting point to learn wireless sensor networks?

    i'm planning to learn about the wireless sensor networks,i don't know where to start with. anyone tell me about the subjects to be learned for WSN and the tools needed for simulation and practical study

    Bruno Senzio · University of the Ryukyus


    I might suggest to begin with a basic approach. Try to learn WSN with Xbee devices. They are really easy to configure and the learning curve is not steep. I would suggest to try learning Xbee and Arduino. There is a lot of information on Digi International's website(Xbee manufacturer) and a good book to understand the use of these devices:


    Hope it is useful somehow

  • What is the method to convert the obtained enzyme values by fpase method into IU units?

    For example

    Production of cellulase was analysed by Dinitrosalicylic acid (DNS) and Filter paper
    assay methods. In the DNS method, maximum enzyme production of 3.9 IU was achieved.

  • Akash Mondal added an answer in Wireless Networks:
    What is the best routing protocol in WSN to maximize the lifetime of WSN and how can I implement it in cooja simulator?

    I need your help. to achieve my project .

    I want to implement routing algorithm in non-uniform deployment  WSN to maximize the lifetime of it in cooja , so , what is the best routing algorithm for this target and how can I implement it in cooja ? what is the code ? 

    is the LEACH is the best way for WSN lifetime or not ?

    Akash Mondal · IIT Kharagpur

    Yes, LEACH is probably the best protocos for maximizing lifetime of WSNs

  • Alireza Talebian asked a question in Dental:
    Does anybody have experience in reporting psycholoigical profile of patients visiting dental general practitioner ?

    Please send a full text about the subject.

  • Nilanjan Dey added an answer in Image Registration:
    Can anybody recommend a paper that talks about recent methods in image registration techniques?

    Recent Image Registration techniques in single-modality and multi-modality

    Nilanjan Dey · Bengal College of Engineering and Technology

    You can go through one of my recently published paper:

    Tadashi Araki, Nobutaka Ikeda, Nilanjan Dey, Sayan Chakraborty, Luca Saba, Dinesh Kumar, Elisa Cuadrado Godia, Xiaoyi Jiang, Ajay Gupta, Petia Radeva, John R. Laird, Andrew Nicolaides, Jasjit S. Suri:
    A comparative approach of four different image registration techniques for quantitative assessment of coronary artery calcium lesions using intravascular ultrasound. Computer Methods and Programs in Biomedicine 118(2): 158-172 (2015)

  • Paritosh Prashar added an answer in Cloning Vector:
    Does anyone know what primers I can use to sequence a pCAMBIA1300 based vector?

    Hello, are there any universal primers I can use to sequence through the MCS of a pCAMBIA 1300 based vector?

    Paritosh Prashar · Daiichi Sankyo India Pharma Pvt. Ltd.

    5′ sequencing primer AACAGCTATGACCATG
    3′ sequencing primer GTAAAACGACGGCCAGT


  • Akash Mondal added an answer in NetSim:
    Any help with cognitive radio network Simulation in NetSim?

    I have started working on CR simulation in NetSim from Tetcos, and wanted to know how does the secondary switch if the primary comes on ? To which frequency does it shift ? And also what are the modulation schemes used ?


    Akash Mondal · IIT Kharagpur

    Thank you for the presentation, and it was very helpful in understanding the internal working on NetSim. So have two questions

    a. Even in Cognitive Radio simulation, are the same 10 + 1  types of events there ? I.e IN and OUT event for all 5 layers APP, TRANSPORT, NW, MAC and PHY ? Plus the timer event ?

    b. So I see lot of functions like ZIGBEE_UNSLOTTED() which is macro for function fn_NetSim_Zigbee_UnslottedCSMACA(pstruMetrics,pstruDevicePower,pstruEventDetails ).  Then when I go to definition, it goes to another macro and so on. Can you explain how these macros work ?


  • Hui Huang added an answer in Elastic Modulus:
    Lesser Tangent modulus values of low carbon steel is giving less deformation: Why ???

    I am conducting some welding experiment on low carbon steels. The bilinear isotropic hardening is considered in our elasto-plastic model. I have conducted the welding analysis considering different values of Tangent modulus (other parameters are remaining same). The Tangent modulus considered are: 16% of E, 1% of E, 0.2% of E and 0.1% of E, where E = Elastic modulus of steel. The lowest deformation is coming for 0.1% of E of the Tangent modulus. And this one is nearly matching with the experimental value. Why it is so? What are the guide lines for choosing the tangent modulus? Kindly help. Thanks in advance. 

    Hui Huang · Osaka University

    Dear Debabrata Podder, 

    It is a tough question. I also had some confusion. In my current simulations, I usually employ 0.5%E as the hardening modulus. And the value are roughly in accordance with test data as I observed in a company.

    I tried to understand the phenomenon using inherent strain concept. E.g, the plastic strain of a two-end fixed bar is ep=-SY/E after a heating-cooling cycle, with strain hardening, the value of SY becomes larger thus ep will be larger (absolute value). As constraint in models with/without strain hardening are similar, more deformation will be induced in the case of model with strain hardening . Related papers can be found in the attachment. Hopefully, it is useful for you.

    Kind regards,

    Huang Hui

  • Inu Rawal asked a question in Bacterial Diversity:
    What is shannon diversity index?

    My work is on bacterial diversity. I want to know about shannon diversity index? what is the formula? how can we compare two communities' diversity on the basis of this index?

  • D. Kalaivanan added an answer in Cultivation:
    Research papers relevant to soilless cultivation of vegetables, fruits and flowers on cocopeat under protected conditions?

    There are plenty of substrate (organic and inorganic) used for soilless cultivation of vegetables, few fruit crops and flowers under protected conditions. Kindly share  If anybody is having the research experience or research papers on soilless cultivation of vegetables, fruits and flowers on Cocopeat. 

    D. Kalaivanan · Indian Institute of Horticultural Research

    Thanks Joseph for providing useful link

  • Matt Falcy added an answer in Correlation Analysis:
    How can one make sure that his/her sample already contains sufficient data for a meaningful correlation/regression analysis (in ecological studies)?

    I am looking at temporal changes in the vegetation cover in an area and aiming to examine these changes against several potential drivers. I have 6 points in time for my temporal studies and am now wondering if the outcome of correlation analysis of 6 points would be meaningful. 

    Matt Falcy · State of Oregon

    If the actual change is large relative to the unexplained variance, then you will need fewer data to declare "significance".  If the actual change is tiny compared to unexplained variance then you will need a lot more data.  Although two points is all you need to connect a line, you still won't be able to tell there is real change or just random fluctuation.  Typically, a power analysis is done to inform the amount of data you should collect.

    The sensitivity of your conclusions about change to the sample size you happen to have should cause some contemplation.  See Johnson's (1999) classic paper on "The insignificance of statistical significance testing" (Journal of Wildlife Management) and the recent special edition of Ecology vol 94, 2014 on the use of P-values.  

    I think a key thing to note is that null hypothesis testing of "change" isn't very meaningful until it is placed in a broader context (most things in nature are inter-dependent, so just get enough data!).  To this end, see Dixon's (2005) paper in Ecology on "A statistical test to show negligible trend" or consider a Bayesian analysis that yields the probability density of different magnitudes of change supported by your data, given your prior belief about change.  Ideally, you would have multiple competing models of what is driving change in veg cover, and then use AIC or it's variants to evaluate the relative strengths of these models (see Burnham and Anderson 2002 book titled; Model Selection and Mulltimodel Inference).

  • What is the detailed mechanism of PMA differentiation of U937 cells?
    I used concentrations 10 ng/ml , 50ng/ml , 250 ng/ml but the last concentration has less macrophages and dead cells than 50ng/ml, what is the reason?

    I know that PMA mimics DAG which is a PKC activator and so PKC affects gene regulation but I need details. I searched but couldn't find information.
    Abu Hasanat Md. Zulfiker · Griffith University

    Hi, I am doing immunofluorescence with U937 cells to show the localization of NF-kB after 1 ug/mL LPS + 30 ng/mL PMA. After stimulus with 1 ug/mL LPS + 30 ng/mL PMA, the NF-kB should be in the nucleus and I have seen that in the confocal. And without 1 ug/mL LPS + 30 ng/mL PMA, NF-kB should be in the cytoplasm. Normally, after addition of 1 ug/mL LPS + 30 ng/mL PMA, the cells become adhered to the coverslip and easy to work with the coverslip for fixing and getting ready for the confocal. But I am facing difficulties without stimulus because at the end of the experiment (fixing and series of treatment with primary, secondary antibody and DAPI), it is hard to find the cells for confocal. So, if I add same amount of only PMA (not LPS) for limited period of time (at least 4 hours, actually I am not sure which time period would be optimum) to become attached the cells in the coverslip, still NF-kB would be in the cytoplasm? or would it be reasonable to do this to compare treated and non-treated?

  • What are the recent terminology and concepts in the field of child development?

    Are any specific terminologies added to the field of early childhood education, child development and family theories.

  • Ricardo Alvarez added an answer in Oceanography:
    Sea surface temperature 80- 90's?

    HI everyone,

    I'm looking for images (GRID - ASCI-GEOTIFF) about SST (sea surface temperature) in the 80's & 90's (per year). I've looked all over the web, but it has been complicated find it something useful. Any comment or help will be greatly appreciated!! Cheers


    Ricardo Alvarez · University of New South Wales

    Sorry Eduardo but, What's mean abhor?

  • Can anybody tell me which screening method will be best to identify the most suitable genotypes for salt tolerance?

    Few screening methods like In-situ Field Evaluation, Microplots, Pot experiment and Hydroponics are adopted by several researchers. Which method should I prefer and why?  Is there any other advanced method of screening other than these? Please share your expertise.


    Girish Chand Srivastava · Amity University

    Yes, you can go for membrane injury index to find the salt susceptible or tolerance.

  • Mani Dhingra added an answer in Urban Design:
    Can anyone suggest resouces that outline urban design principles for typical streetscapes and housing configurations ?

    I am investigating urban design principles for typical streetscapes and housing configurations.

    Mani Dhingra · Integrated Research and Action for Development (IRADe)

    Dear Heath,

    I think you should definitely refer to Kevin Lynch book 'Image of the City' for basic UD elements. 

    Also, Please refer to following links



  • Black gastropod identity?

    Hello everyone,

    interesting black gastropod shell with "chopped-off" - like apex was collected from Mangroves of the west coast of India. Can anyone identify the shell?



  • Venkatesha NJ added an answer in Nanochemistry:
    What is the pore size distribution by BJH method?

    Could help me please, what is the procedimeinto to calculate the pore size distribution by the BJH method, what is the equation and what corrections made are

    Venkatesha NJ · Bangalore Institute of Technology

    you can go through the text book/ but still better use computerized calculations means calculated values by software. 

    Surface Area and Porosity Determinations by Physisorption: Measurements and Theory

    James B. Condon
    Elsevier Science, 27-Sep-2006 - Science - 296 pages


    if you are unable to get this book, i'll attach PDF for text book...

  • Akash Mondal added an answer in ns-3:
    I'm working on VANET application research. How can I add some information in SUMO trace file that it will be used as input to ns-3?

    I'm working on vanet application research. How I can add some information in SUMO trace file that it will be used as input to ns-3, the information like defining areas coordinates, areas conditions ...etc??

    Akash Mondal · IIT Kharagpur

    I have used it for NetSim from TETCOS, and from the comments in given code, I see that it is same for NS-2.

    A user wishing to simulate Vanet Scenario can place the nodes randomly at any position and start the simulation. The device Initial and Intermediate device Postions will be taken care by the following three functions

    The function FileBasedMobilityInitializeNodePosition(int ); sets the initial positions
    of the nodes.

    The function FileBasedMobility(int , double ); is defined to change the position of
    the current deiveceID and to read the next Position Change of the current deviceID
    and add this Event to the List of events to be performed.

    The function FileBasedMobilityPointersFree(int ); closes the file and frees all the

    The standard format would be

    #nodes: 5 max x = 1000.0, max y: 1000.0
    $node_(0) set X_ 0.6642883828044
    $node_(0) set Y_ 0.2309939067026
    $node_(0) set Z_ 0.0
    $node_(1) set X_ 50.6642883828044
    $node_(1) set Y_ 50.2309939067026
    $node_(1) set Z_ 0.0
    $node_(2) set X_ 100.1527892303775
    $node_(2) set Y_ 100.0017151661647
    $node_(2) set Z_ 0.0
    $node_(3) set X_ 150.3207048718017
    $node_(3) set Y_ 150.7817679768309
    $node_(3) set Z_ 0.0
    $node_(4) set X_ 200.6792971281983
    $node_(4) set Y_ 200.2182340231691
    $node_(4) set Z_ 0.0
    $time 0.0 "$node_(0) 0.00 0.00 0.00"
    $time 0.0 "$node_(1) 50.0 50.0 0.0"
    $time 0.0 "$node_(2) 100 100 0"
    $time 0.0 "$node_(3) 150 150 0"
    $time 0.0 "$node_(4) 200 200 0"
    $time 0.05 "$node_(0) 50 0 0"
    $time 0.05 "$node_(1) 100 50 0"

  • K. Sreenivas added an answer in Yttrium:
    Is it possible to evaporate a 4 inches YSZ (Yttrium stabilized zirconia) target in a sputtering process with a DC power supply?

    I am using a MDX-1K Advanced Energy power supply. And it is a Unbalanced Magnetron sputtering system.

    K. Sreenivas · University of Delhi

    You can try dc magnetron, But I doubtful, it may not work.

    Best is rf magnetron, or rf diode sputtering.

    Alternately you can try e-beam evaporation.

    In case you don't have such options,


    You can also see in the literature, some simple chemical methods are available now.

    K. Sreenivas

  • Athianos Stergios added an answer in Stock Pricing:
    In calculating market ratios, how can I deal with firms having no or little trading activity?

    I am conducting a research where i need to calculate z-scores and some other market ratio. I selected about 316 manufacturing firms listed at KSE for 15 years range from 1998 to 2013. I collected daily stock prices and took mean for a particular year observations. i also need to calculate average daily returns and stock volatility. However, there are number of companies having no activity or very few days activity (like 10 or 15 days) for a particular whole year. Including such year observation can provide biased results. How can i deal with this problem?

    please suggest and recommend actions with references.

    Athianos Stergios · Technological Educational Institute of Central Macedonia at Serres

    Hi, I believe it’s better to exclude the specific companies. That helps you to achieve normality to your sample.  After that you have also to restate your sample and period of examination. It is more suitable to set different time frames (or time classes) in case that you still want to examine the initial number of companies because different economic factors may affect your sample significantly. Finally, E-views could be suitable for your analysis.