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  • Physical activity, diet and reducing depressive symptoms

    If one (young teenager) was to increase physical activity or improve diet have soon could you see reductions in depression symptoms?

  • Artem V Badasyan added an answer in Crosslinking:
    How can light scattering be used to assess polymer network homogeneity?

    I know the general background of using light scattering for determining e.g. molecular weights. I would appreciate, however, comments on the uses of light scattering on the characterization of polymer networks in dry or in wet/organic solvent swollen state. I am specially interested in assessing crosslink density, mobiltiy and homogeneity of network formation. I did some preliminary literature search but I am not a specialist in this field, therefore I would welcome comments from colleagues, who have practical experience in this field. If it can be used for network homogeneity assessment, hat is the experimental arranegement? What is the spatial resolution?

    Artem V Badasyan · University of Nova Gorica

    Hi guys! A stupid question from a theoretician -- are you sure that the METHOD of light scattering can be applied to studies of dense polymer solutions? At university I was taught that UV-vis, CD and light scattering work up to semi-dilute regime of polymer solution, but not for concentrated. Since then the Nature may have changed, but I strongly doubt that ;-)

  • Sandeep Rawat added an answer in FRAP:
    How can I correlate my FRAP and total phenols results?

    Do I just plot the two columns of data on excel and get the R squared value?

    Sandeep Rawat · CSIR - Institute of Himalayan Bioresource Technology

    Use Simple Pearson Linear Correlation.

    Putt your values in two column as variable and drow a scattered plot.

    plot the regression line and display R2 value calculate r value and match with standard critical values for correlation coefficient. if these values are higher than reported values then it is significant at  this level..........

  • Adam Lapicki added an answer in DC Sputtering:
    How do I improve film quality with DC Sputtering?

    Im doing DC sputtering on quartz for lithography purpose. The film ingredient is Chromium. I got a problem where there is uncoated area which degrade the film quality. After doing investigation majority problem came from particle that stick on the quartz before sputtering. So, i will try using trinch ionizer. If you have other idea please tell me.

    But in other hand, i think the evaporation process also need to be improve. Is there any way can overcome this problem of peel off/uncoated area ?

    Adam Lapicki · Seagate Technology (Ireland)

    Agree with Tillmann - it is clearly a surface contamination issue, likely organic, piranha solution will work well is such cases without degradation of quartz itself due to the the oxidative character of the piranha etch and the fact that quartz is essentially saturated with oxygen. Any HF solutions will cause some damage to quartz. Using acetone (should be followed by alcohol to remove residues) and alcohols may also work, depending on the nature of contamination.

  • Avinash Kumar Chouhan asked a question in Gravity:
    How to Calculate Total Horizontal Derivative of Bouger Gravity Anomaly in Geosoft?

    I have Calculated Horizontal Derivative in X and Y directions. Bur i have to calculate THD using Geosoft Software. How it can be done?

  • How a decision making method can be termed as precise (accurate)?

    multi criteria decision making method in supply chain management

  • Arunas Kazlauskas added an answer in Western Blot:
    What are possible causes of faint/disappeared middle part of band and of non-straight line band in Western Blot (figures attached)?

    Could you kindly help me to specify what could be possible cause of my problem with band in Western blot as showed in my attach picture? picture 1 is 40 kda, picture 2 is 60 kda.

    1. Some time, the band is not straight, a bit deformed like the leftmost band in the figure 1.

    2. I often get the band which has faint or disappearing in the middle part as most band in both figures and especially second rightmost band in the figure 1.

    I use Biorad's Mini-Protean system, 10well, 1.5cm comb, sample solution is 5 uL/well, homemade SDS-PAGE gel: 12% resolving and 4% stacking, SDS running buffer, running at 60V for 10min then 200V for 39min, fresh Towbin with 20% methanol transfer buffer, clear bubbles with glass stick, transferring at 100V for 1hr. The membrane is PVDF, wet with 100%methanol for 1min and transfer buffer for another 15min.

    Thank you so much


    Arunas Kazlauskas · Lithuanian University of Health Sciences

    Hi, in order to solve a "crooked band" problem, start loading your samples not from the very edge (although sometimes it is impossible if you need to use all 10 wells). Thus, in your figure 1, you should have additional, sample-free wells loaded with the loading buffer only (with/without the size marker) at each side of your series of samples. Also important that you make sure that all your samples have an equal amount of the loading buffer. 

    Regarding the second problem, to me it looks like there is an unequal amount of the substrate used on the middle area of the gel. The background looks different over there. Alternatively, as it has been noted by Elena Yu. Filinova, you may have jus loaded smaller amount of sample due to the accidental gel pushing.

  • Kenneth E Miller added an answer in Psychosocial:
    I'm looking for Arabic language measures of children's mental health, psychosocial wellbeing, and family relationships. Any suggestions?

    At War Child Holland, we want a simple and brief set of measures, in Arabic, that we can use for a simple pre-post evaluation of our life skills intervention. Not high level research, just an initial assessment of change over time.  Thanks!

    Kenneth E Miller · War Child Holland

    Thanks very much, Ian.

  • Brett O'Bannon added an answer in Armed Conflict:
    What woould be the appropriate theoretical approach to study the impact of armed conflict on women?

    Currently doing field research on the impact of armed conflict on women in conflict-affected areas in the Sudan, we are proposing a literature review as part of the introductory chapters of the research, seeking assistance on the most recent theoretical work done on this area.

    Brett O'Bannon · DePauw University

    Many UN agencies have developed their own methodologies for inflict analysis, some of which have particular sensitivity to gender. UNICEF is one you might search for their publications. Here's something recent they developed with Search for Common Ground that may prove useful. 

  • Babatunde Olufemi Adebesin asked a question in PEAKS:
    What inference can be deduced from the fact that the pre-reversal enhancement magnitude during June solstice peaked 1 hour after other seasons peaked?

    I am carrying out an investigation on plasma drift during the evening time, I observed that the average PRE magnitude for a complete solar cycle during the June solstice (covering May to July) peaked an hour after all other seasons had peaked. What could be responsible?

  • Terry Grapentine asked a question in Social Science:
    Can you provide references for semantic networks in construct development in the social sciences?

    Want to learn more about semantic networks as they are used in construct development

  • Oyeyemi Oyelere added an answer in Comsol:
    How can I model water in-crude-oil emulsion treatment using microwave heating?

    I am working on a project "Modelling / Simulation of Water-in-Crude Oil Emulsion Treatment Using Microwave Heating Technology using Comsol.
    I am new in using Comsol software and I will be glad if anyone in the house can guide me.

    Oyeyemi Oyelere · oyeyemi.oyelere@saipem.com

    @ Viran Mahida, Please kindly explain further.

    I want to simulate water in-crude-oil emulsion treatment using microwave heating

  • Tomas Machacek asked a question in Cercaria:
    Do you know about some published example of attenuation of cercariae infectivity after "passaging" the parasite life cycle in the laboratory?

    Personally, I am convinced this happens (based on my own 3-year experience with the same parasite strain) but I haven't found it in literature for any helminth.

  • Is it possible to measure both peptides and metabolites on the same triplequad?

    I am working in a lab which does extensive metabolite analysis using triplequad (Bruker EVOQ Elite) and QTOF (Bruker Compact) instruments.
    We are about to set up a method for measuring peptides as well.

    We have had some good initial results, but we can't seem to get the sensitivity we want
    (and which is reported from other labs).

    When we do direct infusion of peptides to optimize for collision energies, we tend to get high signal for some small m/z's which does not match the peptide b/y fragmentation.

    At one point it was suggested that the instrumentation needs to be actively calibrated for peptides or metabolites,
    due to the varation in chargestates and how the ion optics would perform on these.

    Is this true? We are currently getting very good results when measuring metabolites, but very low signal when we measure peptides. We are about to contact the instrument vendor for support, but I just wanted to hear what the community thinks about this.


    Sergey Kovalchuk · Russian Academy of Sciences

    By the way, what do you mean by low intensities? What peptide concentration do you use? What is your injection parameters? Nano or Micro spray? What kind of peptides do you use? Every peptide has its unique concentration-to-signal ratio, thus it is theoretically possible that all your 20 peptides are not very good ones for ESI. It can really depend on their AA sequence. 

    Ion supression has nothing to do with sample complexity. It can happen even for two peptides mixture, if they coelute in HPLC or you just inject them together, and one of them would suppress ionization of the other. More problems with ion supression arise when you do not know for sure peptide composition of your sample. And when you do MRM experiment you have no idea whether there is anything coeluting with your target peptides (you just do not control MS1 signal to know whether there is anything else coeluting), which might interfere with them.

    Actually, ion supression in ESI is a tricky thing, much more so than in MALDI. But anyway, even if you have ion supression for one component you should see another component so much clearer. Besides, you are supposed to see both peptides whatever, with just lower intensity for one of them in comparison to this peptide alone.

    Very low m/z region is absolutely useless for peptide MRM, since it is not specific at all. I would recommend do not even measure this region when doing CE ramping for fragmentation optimization. You can start with m/z 100-150. Actually, when you go to more complex samples for your MRM analysis the higher m/z you use for fragment ions in MRM transitions the less background noise you would get. Some people recommend to use fragment ions with m/z higher than parent ion m/z. Well, if you have such fragments - perfect. But usually they are far from being the most intensive transitions. And either you get lower background for high m/z but low intensity transitions or you have high background for low m/z but high intensiity transtions you would end up with the same signal-to-noise ratio that is the ultimate estimation of your sensitivity and selectivity. 

  • Do there exist any algorithms to transform an artificial neural network into its open equation form or its equivalent?

    I am asking the community here to get a brief overview if there exist a method or algorithm, that enables me to transform a traditional perceptron based feed forward artificial neural network into its open equation form?

    The closed for of an equation for a linear system for example is

    y =  kx + d and its open form is  R = y - kx  - d

    Any idea or hint is appreciated.

    Kind regards and thank you in advance.

    Wolfram Rinke · Fachhochschule Burgenland, Austria, Eisenstadt

    Hi Rok, thanks for your feedback. I will look into this papers, that you refered to.

  • Abiola edobor-osoh asked a question in Waste Products:
    What methods can be used in the synthesis of a nanoparticles from agricultural waste products?

    I want to synthesize nanoparticles from agricultural waste for biological application such as drug delivery.

  • Can anyone suggest me some bacterial strains name those are totally plant pathogenic ?

    Dear researcher i have some problem in searching of plant pathogeni bacterial strains because some bacteria available in more than one strains no. so please suggest me some plant pathogenic bacterias name with species

    Kalpna D. Rakholiya · Junagadh Agricultural University

    Pseudomonas syringae pv. syringae

    Xanthomonas citri

  • Dipjyoti Das asked a question in Values:
    How to calculate Lm/W value and Cd/A value of an OLED?

    Can anyone explain how to calculate Lm/W value and Cd/A value of an OLED? Also how to calculate the EQE and IQE of an OLED.

  • Billal Nia asked a question in Plant Extracts:
    DL50 or ED50?

    When we want to test the toxity of plant extract on an insect, which mesure we must calculate  DL50 or ED50?

  • Justas Dainys asked a question in EU Projects:
    Does anybody have EELREP 2005 report paper?


    does anybody have this report?:

    EELREP 2005. Final Report: Estimation of the Reproduction Capacity of European Eel. EU-project EELREP (Q5RS-2001-01836). http://www.fishbiology.net/EELREP_final_report.pdf.

    it is not available online anymore.. :(

  • Mikael Niku asked a question in Cryosections:
    Showing bacteria in intestinal paraffin sections?

    I'm trying to visualize intestinal bacteria in paraffin sections. The problem is, the bacterial cells seem to shrink so much that no shapes are preserved, they are all just tiny roughly circular objects. This happens with both routine PFA fixation and with a Carnoy fixation recommended for this purpose (both followed by a standard processing to paraffin sections). What should I do differently? Or is paraffin somehow completely incompatible with this purpose, should I use cryosections instead? I'm planning to use Gram staining and 16S FISH to actually detect the bugs.

  • How do I determine mathematically if a rational expectations equilibrium is fully or partially revealing?

    Xavier Vives defined fully revealing and partially revealing  rational expectations equilibriums in the pages 80-81 of its book, Information and Learning in Markets: The Impact of Market Microstructure.

    I understood the literrary definitions but how mathematically we can prove if a REE is fully or partially revealing?

  • How beam hardening effect on the image noise and radiation dose in single and dual energy CT ?

    How to evaluate  the effect of beam hardening on the image noise and radiation dose in single and dual energy CT?

    Wesley Turner · SimQuest LLC

    On quick addition to the above. Beam hardening affects both the quantity and quality of the noise in the image. Streak artifacts are essentially "coherent" and reduction of streak artifacts cannot be approached using common noise models.

  • Dachuri Vinay added an answer in Lipase:
    Any suggestions on lipase purification with His tag?

    hello every one, i am expressing lipase protein with N.terminal His tag. some have His tag is not working. i am loosing great amount of protein when i do nickel affinity cinematography, i changed my His tag to C-terminal, my protein lost the activity. so i continued to work with Protein contain N-terminal his tag. but when i purify my protein further, lot of junk protein is still remained in the sample. can any one suggest me the solution for solving this issue.

    Dachuri Vinay · Daegu University

    thank you for the reply.

    i am using pET 28A vector. induced with with 1mM IPTG. i am equilibrating with 5mM, washing with 50mM and eluting with 400mM imidazole. at this concerntration of washing i am getting 50% junk protein in elution. 

  • Quantification of cDNA
    while using "Nanodrop" for quantification of cDNA, one should quantify it as double-stranded DNA or single-stranded DNA?? I am using Fermentas kit for first standsynthesis of cDNA from total RNA and m not using RNaseH to degrade the RNA
    Silvia Tyciakova · Slovak Academy of Sciences, Cancer Research Institute

    This is an interesting question. This time I cannot use housekeeper in RT-qPCR because of mix of human and mouse cDNA and just today I measured cDNA after cDNA clean-up on Nanodrop. Here I give you some results:

    1/ the whole reaction mix from RT with RNA, oligos, dNTPs, before clean-up: sample 1 - 1058,6 ng/ul, sample 2 - 1100,3 ng/ul (ssDNA-33 "sample type")

    2/ after clean-up: sample 1 - 128,9, sample 2 - 45,8 (ssDNA-33 "sample type") and for comparision: sample 1 - 196,8, sample 2 - 67,4 (for dsDNA-50 "sample type") and sample 1 - 162,2, sample 2 - 57,5 (for RNA-40 "sample type") - the peaks were very nice...

    So without housekeeper gene I will measure the cDNAs using ssDNA-33 "sample type" and dilute them to give approx. the same amount of cDNA per reaction and run the qPCR.

  • Swapnil Punyapwar added an answer in Plant Biology:
    I am looking for a formula used to express MDA in nmol g-fresh weight after using Heath and Parker
    I am looking for a formula used to express MDA in nmol g-fresh weight after using Heath and Parker
    Swapnil Punyapwar · BITS Pilani, K K Birla Goa

    Ok got it. Thanks a lot.

  • Matteo Pusceddu added an answer in BDNF:
    Can anybody suggest a good ELISA kit for BDNF protein levels from rat cell cultures, please?

    I work with rat cortical primary cultures and looking for the best ELISA kit for the detection of BDNF protein levels. I am also wondering if detection is possible either from supernatant or from protein cell extract. Really thanks

    Matteo Pusceddu · University College Cork

    The shortest answer ever

  • Hamza Kheddar asked a question in Cybersecurity:
    What is the best journal to publish a paper on it?


    What is the fast and best journal with Thomson reuters indexing for cybersecurity, speech coding and telecommunication in general?

    for me i prefer IEEE but i don't know how long it'll take? please advice  

  • What could be responsible for the magnitude of plasma drift to be smallest during June solstice most often out of all seasons?

    Seasonal investigations of vertical plasma drift had always shown June solstice recording the smallest magnitude.

  • Thanh Nguyen added an answer in C++11:
    How can I deal with 1 million agents in C++11 multi-threaded simulation model?

    I'm currently working on ABM model implemented in C++ which utilize Monte Carlo dynamics. In large scales it run much to slow, so have to be converted into multi-threated application (at least up to 32 threats).

    Theoretically the best way to synchronize would be mutex in each agent, but according to Stroustrup "mutex should be treated as a handler to limited system resource", so I doubt that it is possible to use millions of mutexes concurrently.

    Thanh Nguyen · Le Quy Don Technical University

    Milions of Mutex with limited number of threads (e.g up to 32) is not the problem. It still can work well. 

    You can try to use Poco C++. It has NotificationQueue, NotificationCenter, ThreadPool, etc. http://pocoproject.org/  It is a good C++ library with many design patterns.