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  • Anthony Tibaingana added an answer in Food Insecurity:
    What are the possible methods of measuring food insecurity at household level in an agrarian community?

    I am currently working on the impacts of flooding on food security in an agricultural community. I want to know the methods (if possible equations) that have been used to measure food insecurity as well as vulnerability in other agrarian communities at household level. Thank you.

    Anthony Tibaingana · Makerere University

    Food security or insecurity have many dimensions. The best way to measure it in general perspective are given above, but you should also look at specific context such as number of meals expected by the community or household, nutritional value in the food, availability of the food desired not just accessible, time of eating agreed upon and desired or recommended and quantity recommended.  

  • Sarjan H N asked a question in Lysis Buffer:
    How to get the isolated bone marrow cells?

     I have isolated the bone marrow cells from rats by using PBS and RBC lysis buffer. After isolation, i have kept the suspension in HBSS under refrigeration. When i retrieve the same cells after few hours, cells were aggregated as slimy clumps. What could be the reason for this ?. How to keep the cells for longer time under freezing condition ? 

  • Rasanthi Wijesinghe added an answer in Bacterial DNA Extraction:
    Anyone familiar with bacterial DNA extraction from stationary phase?

    Hi everyone.

    I'm trying to extract DNA from Gram-negative bacteria through a metabolic process, and using the GeneElute Bacterial Genomic DNA extraction kit (Sigma)

    My set of samples covers the entire growth curve. At the beginning of the process, during the exponential growth phase, I don't have any problem and although sometimes there is some degradation, I can observe a nice chromosomic band at the top of the gel when running agarose gel electrophoresis. The problem is when the process is more advanced, because the bacterial culture enters into the stationary growth phase. At this stage, DNA appears to be degraded.

    Does any one any tip to improve the quality of the material obtained? 

    I attached an image of the last extraction

    Rasanthi Wijesinghe · United States Geological Survey

    Before DNA extraction, pellet your cells, and wash with 1x PBS to remove any accumulated toxins, especially, during the stationary phase. 

  • Oscar Mañán added an answer in Economic Inequality:
    Can there be any floors and ceilings acceptable as the limits of social and economic inequality?

    Concentration of output, wealth, and assets has no limits as of yet. The market economy does not favor either of the binding upper and lower benchmarks. But the consequences are really painful for the humanity. Can't be there any understanding among the economists and other social scientists on the limits of inequality which can be enforced institutionally?

    Oscar Mañán · University of the Republic, Uruguay

    The limits for inequality are the same limits of capital acumulation, biological limits of the life

  • Taryn Vian added an answer in Qualitative Research:
    How can I do qualitative research interviews by e-mail?

    I plan to interview a couple of experts in a field and find out which skills they consider most crucial for success in this field and how these skills can best be trained. Instead of speaking with these experts and then transcribing our conversations I consider doing the interviews in the frame of e-mail exchanges. Now I am wondering how such e-mail interviews can be done in a methodologically correct fashion. So I am grateful for direct recommendations or hints at good sources..! Cheers

    Taryn Vian · Boston University

    See this article which might be of interest: http://www-ncbi-nlm-nih-gov.ezproxy.bu.edu/pubmed/25748475 

  • Ana Karacic added an answer in Entomology:
    What can I offer to Tuta absoluta adult to eat, what is the best food?

    I have raised small population of Tuta absoluta in entomological cages on tomato plants. And adult of Tuta absoluta was fed on sweet water, but did not live very long. What else could I offered?

    Ana Karacic · Federal agromediterranean institute of Mostar

    duhan, rajčica, krumpir, patlidžan,...to su naša iskustva. (imago živi mnogo kraće u odnosu na sve razvojne stadije, a za ostale razvojne stadije dobra je hrana plod i list navedenih povrtnih vrsta).

  • Rossen Buyukliev added an answer in Aromaticity:
    Could an electrophile attack the meta position on the aromatic ring?

    NH2 group on aromatic ring is para and ortho oriented group. Could an electrophile attack the meta position on the aromati ring? and in which cases?

    no other substituents are on the aromatic ring

    Rossen Buyukliev · Medical University of Sofia

    Add aluminium trichloride to the reaction mixture. Forms complex with positively charged nitrogen, which is directing electrofiles in meta-position.

  • Allard Jan Van Marle added an answer in Experimental Fluid Mechanics:
    How can I determine scaling of error with time between a coarse and a fine grid when solving advection equation?

    I have simulation results for a particular problem (say 1D advection equation) for two grids. One is a coarse grid while the other is refined. I wish to determine the error scaling with time between the two grids theoretically (using pen and paper). Can I do this?

    Allard Jan Van Marle · University of Leuven

    Regarding the answer by Martin George Ross:

    This is a way to do it, but keep in mind, that the courant condition has to be satisfied, otherwise the result becomes invalid, so for a given velocity the smallest grid cells have to determine your timestep.

  • Zorica Đurić asked a question in Balkans:
    Does enyone have experience about abundance of Tuta absoluta in Mediterranean countries?

    Did the number of Tuta absoluta go lower during last few years in Mediterranean countries and Balkan area?

  • Gederts Ievinsh added an answer in Peroxidases:
    What is the Guaiacol peroxidase activity in roots of Phragmites australis?

    Does anyone know what is the guaiacol peroxidase activity (in mU/mg FW) in roots of Phragmites australis under uncontaminated conditions ? Many thanx

    Gederts Ievinsh · University of Latvia

    Any peroxidase measurement in any plant material, leading to some level of activity, can be used only for comparison, not as absolute values

  • Joanne Millar added an answer in Agricultural Extension:
    What are the challenges in implementing an effective extension service?

    Dear All,

    In my current work I will test different extension services to evaluate the effectiveness of providing information on environment. I have found out of literature different approaches, ranking as the most common: field demonstrations or trainings. Have you work with a more innovative approach? and, what would you consider are the main challenges to provide extension services? which criteria would you consider before implementing it?

    I will most welcome your inputs and ideas.

    Thank you.

    Joanne Millar · Charles Sturt University, Albury

    Dear Miriam,

    Start with finding out what farmers or community members know about their environment and what they do already to benefit the environment. Then ask them what they would like to know and assess their farming system problems/issues. From that information you can develop extension activities and information that suit them. Ask them for suggestions so they feel involved in the process of extension. I have researched farmer to farmer learning methods and found that cross visits or study tours are best- allow farmers plenty of time to look and discuss together

    See my researchgate site for lots of papers on farmer learning



  • Zsuzsa R. Huszar added an answer in Investors:
    Whose interest are regulators are protecting?

    Why are we mostly concerned companies’ and investors’ reaction to regulators or regulations? Why aren't we interested in the objectives/incentives of regulators? Their action or inaction can have detrimental impact on the market and individuals’ wealth.  Does anyone know a study that directly examine regulators and consider their incentives? Whose interest are they protecting? 

    Zsuzsa R. Huszar · National University of Singapore

    Lets consider recent Chinese intervention,s such as restricting or allowing margin trading.  What are the objective expectations (these interventions are actually similar to those of the 2008 short sale ban)?  The US studies show that the bans were harmful to market quality, what are the expectations? 

    I had conversations with European exchange regulators as well as with Asian exchange staff  and asked them to explain what is exactly their objective. Do we want liquidity and pricing efficiency or do we want once in a while support for declining prices which may reduce actually price informativeness.

  • Kenan Lopcu added an answer in Cointegration:
    Critical values Engle-Granger cointegration test?

    Dear all,

    I am applying the Engle-Granger 2 steps cointegration procedure between two time series. After the first regression, I have to save the residuals and check whether they are stationary. I cannot use the standard critical values as they are not valid. My point is: given that I am testing unit root in the residuals (with Augmented Dickey Fuller and Phillip-Perron), and residual are known to be mean 0, I don't have to include neither an intercept nor a trend while performing the test. For n=2 (where n is the number of variables), MacKinnon (1991) does not provide critical values for the "no constant, no trend" case. Should I use the constant case critical values? Or better use Engle and Yoo (1987) critical values? Please find attached both MacKinnon and Engle and Yoo papers.

    Thank you in advance

    Kenan Lopcu · Cukurova University

    The critical values in Engle and Yoo (1987) are given in absolute value. So, don't worry about not having a negative sign in Table 2. Reject the null of no cointegration if your test statistic is negative and the magnitude is smaller than the Table values.

  • Gennady Fedulov added an answer in Information Technology:
    Without the use of modern information technologies to conduct research work possible?

    Dear collegues,thank you very much in advance.

    Gennady Fedulov

    In my view, we should not exaggerate the important role of modern information technologies to conduct research work, in particular, to develop effective algorithms. There are "Complexity Theory" in Computer Science. According to this theory, all "good" algorithms (from the class "P" known as Polinomial time algoritnms)  will always work WELL on any Bad Computer and all "bad" algorithms (from the class "NP" of exponential complexity) will always work SLOWLY on any Good Computer. I think developing of "good" (effective) algorithms does not depend on modern information technologies.

  • Anthony Tibaingana added an answer in Green Supply Chain Initiatives:
    What are the impacts of self-governance of sustainability in international trade?
    Impacts on suppliers, workers, communities and eco-systems in developing countries
    Anthony Tibaingana · Makerere University

    Firstly, the two concepts are complex. To govern means to have charge and once people are left to govern them selves they may have a better  way of finding solutions to their challenges. Thus, for sustainable international business self but guided governance would eliminate may challenges within the system that are perpetuated by the governors external to the context but hurt the running of the business.

  • Duncan M Kimuyu asked a question in Savanna:
    How long does the "magnet effect" of savanna burns last?

    For how many years after a single savanna burn do the effects of fire (especially herbivore preferences) last?

  • Sebastian Felix Schwemer added an answer in Privacy Law:
    Does anyone have information on the privacy right of workers' data?

    Has anyone done research on the privacyright of workers? especially the workers data?

    Sebastian Felix Schwemer · University of Copenhagen

    Regarding the EU, the DG for Employment, Social Affairs and Inclusion might be an entry point, too: http://ec.europa.eu/social/main.jsp?catId=708


  • Brian P. J. Stevens added an answer in Lamins:
    Probable Laminated Claystone, yet stumped on origin. Any Ideas?

    This rock was found in NYC. It may have traveled on/in the ice sheet from as far north as Labrador, or it could have come from more locally. There appears to be some limonite. This rock may have come from dredged up European or other ship's ballast rock, out of NY waterways. Please help me with any ideas you may have. I will try to post a few more photos. Thanks!

    Brian P. J. Stevens

    No I can't specify one coloured with iron oxides, but such a sample would be no surprise. Even post-depositional deposition of minor pyrite could colour the rock  after weathering.

  • Treena I Burgess asked a question in Mitochondrial DNA:
    In naturally aerated soil which would you expect to persist for the longest; genomic or mitochondrial DNA?

    Just wondering if anyone has looked into this

  • Krishnayan Haldar added an answer in Surface Tension:
    What is the relation between drop volume and surface tension of two different liquids?

    Water and surfactant solution both have different surface tension. Also a single drop of these liquids dispensed from needle will have definite volume. Is there any proportionate relationship between drop volume and surface tension?

    Krishnayan Haldar · IIT Kharagpur


           Suppose I know the surface tension of water. Also I calculate the drop volume of water and surfactant added water, by counting number of drops dispensing 1 ml of both the liquids. Can I calculate the surface tension of the surfactant added water drom any direct relationship?

  • Anjali Singh added an answer in Spectroscopic Analysis:
    Why this coloured compound doesn't show any peak in visible range??

    I am working on a cyanobacterium, which has the ability to produce colour in medium (liquid). when i go for spectroscopic analysis this coloured compound does not show any peak in visible (400-700) nm range, while 1 or 2 peak observed in UV range. Why ??

    Anjali Singh · Banaras Hindu University

     I am getting three types of coloured compound like Brown (205, 252, and 322 nm ) , pink (205, 250 nm) and yellow with absorption maxima at 205 nm. 

  • Kenneth M Towe added an answer in Cadmium:
    Does increase in Cadmium and Lead in atmosphere lead to climate change? or affects on rainfall?

    does increase in Cadmium and Lead in atmosphere lead to climate change? or affects on rainfall?

  • Anna Mazzucchi added an answer in Stroop Test:
    Does anyone have experience in using the Stroop color and word test?

    Can you help with educational adjustment?

    We are confused by the adjustment table in the manual - are the years of education total years of education, or years since leaving full-time education, say 16?


    Anna Mazzucchi · Fondazione Don Carlo Gnocchi

    The number required corrisponds to the total  years of education. As, in general, is required in many other testing.

    Best regards


  • Subhashish Tiwari added an answer in Electronic Amplifiers:
    How can I calibrate a Lock-In Amplifier ?

    I have SR830 Lock-in amplifier, started using it recently. The problem is I am not able to set it for proper reading even after reading its manual.

     A photodetector's output is going to Lock-in. When a multimeter is connected to photodetector, the reading is approx. 300 mV. But when Lock-in is connected, the readings are random. Please tell me to calibrate Lock-in properly.


    Subhashish Tiwari · IIT-BHU

    Which type of error are you getting ?

  • Lydia Celia Madjene added an answer in Neutrophils:
    What is the best marker for neutrophil identification by immunohistochemistry?

    I want to identify neutrophil in rat lung tissue by immunohistochemistry. 

    What is the best marker for identification of neutrophil in lung tissue by immunohistochemistry?

    Lydia Celia Madjene · Institut Pasteur International Network

    MPO also

  • Charles W Steinfield added an answer in Social Network Analysis:
    Is social network analysis linking concepts, not people, possible?

    Does anyone know whether it is possible to do social network analysis on social media networks by connecting related concepts (keywords) rather than people, and/or by linking people with keywords? If yes, can you recommend literature on how to do it?

    Charles W Steinfield · Michigan State University

    In addition to all the excellent sources already mentioned, you might do some searching on bipartite graphs or bipartite/affiliation networks, which, as I understand it, allow you to mix different classes of nodes (e.g. one class of node could be people, another class could be some other type of data such as a group membership or other characteristic).  A nice blog entry on this type of network analysis by Solomon Messing can be found here: https://solomonmessing.wordpress.com/2012/09/30/working-with-bipartiteaffiliation-network-data-in-r/.

  • Rivalino Matias Jr. added an answer in Programming C++:
    Why can I not execute software in direct log in, but no problem when execute via ssh command?

    Dear all,

    I wrote a C++ software, which is a data readout from a hardware modules to PC via Gigabit Ethernet.

    I have a problem with executing software when direct log in to Linux computer. This is the case:

    - When I log in the computer from another one via the ssh command, I can execute my software successfully: the PC can access to the module and read out data.

    - When I log in the computer directly, I cannot execute my software successfully: PC can access to the module but usually cannot read data out (just a few times, it can read data out).

    This is a strange behavior to me! I discussed with my lab mates, they just have problems if they login with ssh but everything is normal when direct login.

    Of course, I want my software can be executed when directly login or via ssh.

    Is there anybody experienced this problem?

    I wish for sharing experiences and giving suggestions & advises. 

    Thanks a lot.

  • Andrey Igorevich Svitenkov added an answer in Computational Physics:
    How can I find an equilibrium position?

    Let's have a closed loop made of N (N>3) stiff rods of equal length. The joints between rods may be arbitrarily reconfigured (bent, but always connecting the same pairs of rods) with no cost.  We start with some initial configuration (I'm interested in a threefoil knot made of discrete elements, so the loop doesn't fit into just two dimensions).  There is no gravity. Now we apply some known forces to all rods (either to their centers or to their ends, i.e. joints), arbitrarily oriented and with arbitrary values.  How to find the final configuration?

    I am not interested in pointers to any software.  Rather, I would like to see what kind of equations describes such problem, preferably not the differential equations.  It may be assumed that the sum of all applied forces, as well as their moments, is zero. Is it helpful?

    Andrey Igorevich Svitenkov · National Research University ITMO

    I think it is possible to work directly in the configuration space with dim=2N. Each joint is described by couple of angles (planar and torsion). We can choose the set of 2N angles as new coordinates {qi}. The forces then are given by Fi = -dU/dqi, where U is potential energy of the system (hope, your forces are potential). Such forces will conserve the lengths of rods.

  • Ashawani Kumar Singh added an answer in Alkenes:
    Which reducing reagent is best for reduction of alkene group in alpha beta unsaturated ketone?

    Which reducing reagent is best for reduction of alkene group in alpha beta unsaturated ketone?

    Ashawani Kumar Singh · University of Delhi

    Alessio Caretto thankyou very much