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  • Krishnan Umachandran added an answer in Conflict:
    Do you understand the psychocultural dynamics of conflict expansion in enduring conflicts?

    Why and how small incidents engage so many people so passionately?

    it is through the part played by more indigenous elements such as [domesticity and neighborhood life, or work situations] in the construction of ordinary practices and interactions not exhaustively defined by outside powers that much of the everyday life of the periphery is creolized . . . it is in large part in this way that the shift occurs from a mere diffusion of modernity to the emergence of new diversity. There is great variation here in the personal and situational equations which shape outcomes, and . . . generates the actual cultural continuum

  • Mohamed Ghamry asked a question in Production:
    How to get the gene responsible for the production of a particular product from the microbe?

    Are you asking a question?This field is where you should enter a question about your research. Your sentence should end with a question mark?

  • I need to know the attached physical constans of materials?

    for Cu2O and Pt

    Saeideh Hosseini · University of Zanjan

    you can see the attached links

  • Qazi M S Jamal added an answer in Molecular Docking:
    Free/ open-source docking programs that take good care of bound water molecules?

    Hello there,

    For molecular docking, I know there are some commercial software programs that account for binding site water molecules, with possibilities of displacing, rotating, and translating waters while docking different ligands/conformations. But I wonder if there is any free program that does this well?


  • Jim Dixon added an answer in Sequence Stratigraphy:
    What is the relationship between palynology and sequence stratigraphy?

    I need information about anoxic event and their relation with the sequence stratigraphy. I want to use palynological data if possible

    Jim Dixon · Geological Survey of Canada

    Often, organic material (including palynomorphs) is concentrated within sediments formed during maximum flooding, although their concentration will depend on the amount of sediment influx  at the time of maximum flooding.

  • Alex Grinberg added an answer in RAD-Seq:
    Is cross contamination of individual tags during adapters synthesis a crucial problem in NGS studies?

    On top of standard HPLC purification, some furnishers propose expensive extra purification steps in oligomer synthesis for NGS, to avoid these kind of cross contaminations. However, does this contamination usually reach such levels that would make these extra steps really necessary? What amount of background would these cross contamination create in multiplexed PCR and sequencings (such as RAD seq)?

  • Ute A. Hellmich added an answer in Fluorescence:
    What can be the reason for the poor solubility of potassium channel expressed from Pichia pastoris?

    I am trying to purfiy a human potassium channel expressed from Picha pastoris. The carboxy terminal of the protein is linked with a GFP tag for measuring the level of expression or purification . Now I have some trouble in solubilizing the protein by detergents.I break the picha pastoris with french press (1600bar, 4 times).After ultacentrifugation, I collect the crude membane, resuspend it (Resuspension Buffer: 50mM Hepes, pH7.5, 200mM NaCl, 5mM imidazole)and try several different detegents, like DDM, DM, OG,NG,LDAO(all from anatrace) to solubilize the membrane,the final concentration of detergent is 1%,and the total membrane protein concentration is about 3mg/ml. Incubate the mixture at 4 degree for 1h with mild agitation(I have tried the incubation overnight, It's just a little better).After the incubation, I centrifuge the mixiture at 160,000g for 30mins. Before/after the ultracentrifugation, I measeure the fluorescence intensity and the result is below:
    the fluorescence intensity before/after ulta-centrifugation:
    DDM: 27418/488
    DM: 26612/479
    NG: 38021/453
    OG: 23889/777
    LDAO: 28610/503

    The effect of solubilzation is very poor, I have tried several time, the result is same.
    Has somebody an idea to solve this problem? or what can be the reason for this poor solubilization?

    Thank you for your help

    Ute A. Hellmich · Johannes Gutenberg-Universität Mainz

    I agree with Adam's take. Make sure your protein is really in the membrane. Because you have GFP-tagged protein, you could do fluorescence microscopy and get at least a rough idea (even with a not-so-fancy microscope set-up) whether you see green fluorescence nicely distributed around the cell or in punctae or even in internal structures. 

    If you think protein distribution is not the problem, I'd have a look at your membrane preparation. Are you sure you actually make good quality membranes or could you possibly have a large number of intact cells in your "membrane" preparation? Yeast cells are notorious for their stability. For example, you do not mention a slow centrifugation spin after your french press step to remove intact cells. Such an extra step could help to clear your prep from unwanted debris. Also, what is the consistency of your final membranes? They should be quite soft and "squishy". If you have very whitish, rather "hard" pellets, this could mean that you have a lot of unwanted stuff in your prep. 

    Your fluorescence intensity values indicate that you loose fluorescence during ultracentrifugation or that your GFP stays in the supernatant? (I hope I interpreted this correctly). This could indicate that you either produce soluble GFP without the membrane protein attached to it or that your GFP gets cleaved during the membrane preparation process. In either case, you'd end up with a soluble GFP that naturally would be found in the SN after ultracentrifugation. If incomplete protein translation is the issue, you might want to work on optimizing your expression conditions,. If protein cleavage is the issue, consider adding more protase inhibitors to your sample. You did not mention any of these in your text, but I would highly recommend them. 

    So in summary, using what you've described, I am not convinced your problem is necessarily one of poor solubilization, but it could be another issue altogether that would merit some looking into. 

    I hope this helps some and good luck for your project!

  • Pia Bush asked a question in Eating Behavior:
    Can someone tell me how to score and interpret the scores for the Dutch Eating Behavior Questionnaire?

    Hello, I have utilized the DEBQ for my research; however, I am unable to get English instructions to guide me through the scoring and interpretation of the scores.  Is anyone familiar with the DEBQ-E assessment?

  • Chad D. Touchberry asked a question in RNAlater:
    Shipping RNA from Primary Mouse Adult Ventricular Cardiomyocytes?

    I am treating cultured AVCMs from mice and analyzing gene expression with a collaborator. Normally, I would just isolate the total RNA from the culture wells and perform PCR. In this specific case, I need to ship either the cardiomyoctyes or the extracted RNA to a collaborator. If I extract the RNA then I need to freeze and ship frozen samples. Less than ideal. 

    My other option is to put the cardiomyoctyes in RNAlater. If we use RNAlater, would you scrape the cardiomyoctyes in RNAlater or trypsinize, pellet and resuspend them in RNAlater? I have never had a need to trypsinize primary cardiomyoctyes before and scraping primary cardiomyoctyes seems a bit aggressive. If I recall we had a bit of an issue getting a cell pellet (HL-1 cells) out of RNAlater in the past.

    Any suggestions are appreciated...

  • Abhijit Sarkar asked a question in Gelatin:
    I need your valuable suggestions. Is Poly Vinyl Alcohol water soluble?

    I tried to dissolve it, but it wasn't. It formed gelatin like material. Instead of forming clear solution, it makes some kind of sticky precipitation. 

  • Does anybody knows a good and cheap ELISA to S. aureus enterotoxins?

    I'm studying the effects of culture characteristics on production and secretion of staphylococcal enterotoxins.

  • Hannah Belcher added an answer in Nutrition Therapy:
    Can nutrition therapy treat autism symptoms?

    Parents of children with ASD are frequently asking me about Nutrition Therapy for their children. I need some evidences about the topic. Do you agree using Nutrition Therapy for autism? is there any evidence about it?

    Hannah Belcher · Anglia Ruskin University

    Only if problems outside of the core impairments are present. I think especially for school aged boys parents see they are more calmer on a more balanced diet with less sugar. As far as feeding them extra of things, I don't agree with, food can't cure.  

  • Marvel Lewi added an answer in Capsicum:
    How do I know if the concentration of herbicide for transgenic plant selection is right?

    Explant that I'm using is 7-days old shoot bud's apex without cotyledon.

    I already knew that in certain concentration it will withered after 2-3 weeks incubation.
    At lower concentration from it, I also found some explant that doesn't withered after 3 weeks incubation.

    Explants that do not wither, do not grow at all.
    in fact it is withering on its tips except its bud area.
    While the control shows significant growth after 3 weeks incubation.

    So I'm asking, Is it safe to assume that concentration of glufosinate as the MIC for my explant? Or do I need to go lower concentration?


    • I'm using glufosinate for selection because in my place, only bar/pat cassette available.
    • there is limited access reference about glufosinate being used as selection herbicide for Capsicum.
    Marvel Lewi · Universitas Surabaya

    to Jürgen Denecke,

    sorry for asking too much..

    I still not grasp the idea about the right result or the expected result of the minimum concentration for transformant selection.

    I've already tried different glufosinate concentration on wild type (10 - 100 ppm) then I already know the concentration that can kill wild type (about 30 ppm)

    In 10 ppm, about 90% wild type died and the rest are still green but no sign of growth. In addition, negative control shows a significant growth.

    I'm really confuse whether should I scanning through 10 to 30 ppm or scanning through lower than 10 ppm for a better selection concentration because some journal said the expected result is when the concentration is low enough to kill all of the wild type while the other said when the concentration is low enough to inhibits the wild type so it does not respond at all.

    Would you mind to give me some advice?

  • Gianni Pavan asked a question in VB6:
    Anyone able to write VB6 code to record audio with WASAPI ?

    Low level programming audio I/O for recording sounds and ultrasounds is mandatory for real-time applications; the new core technology developed by Microsoft is WASAPI, however documentation is only available about C and .NET. No documentation is available for the old, but still widely used, VB6. Anyone able to program WASAPI in VB6 or with a code sample to share ?


  • Is there any Iranian fellow willing to collaborate with us on the animal studies of our nanodrug delivery system?

    We have been working on an anticancer drug delivery system based on PLGA-b-PEG copolymer nanoparticles, and now are looking for colleagues who are expert in cancer animal models and related in vivo experiments. Our preferential tumor model is MCF7 breast cancer. Please contact me for further detailed information. Thank you. 

    Farzad Khanipour · Tarbiat Modares University

    Dear Dr. Samadi, 

    It is of my great pleasure to meet you here and read your declare of interest on my project. First of all, I should admit my intense enthusiasm to build up international collaborative relations, especially with dear Iranians abroad. However, considering the restrictions and difficulties of relationship between Iran and the US, I actually don't know by what means such a collaboration would be possible. I assume that maybe after a preliminary in vivo evaluation of our nanodrug delivery system, collaboration on preclinical and even translational bench to beside, developments would be better feasible. 

    Anyway, it is absolutely welcome if you come up with any helpful suggestions about the possible ways that we could collaborate with each other. Thank you very much.

    Best wishes & regards

  • Kenneth M Towe added an answer in Climate Change:
    What is the climate change induced increase (per decade) in surface water temperatures and salinity in the worlds oceans and seas?

    Climate change induced an increase in the surface water temperatures and salinity in various oceans and seas in the world. I need the amounts of their increase per decade in past several years. Please attach the article as references with your valuable reply.

  • Maxim Ryzhkov added an answer in Heat Treatment:
    What is an optimal hardened layer in real steel parts after quenching?

    When bottle with water is frozen through, it cracks. The same is often happening when steel parts are quenched through. To prevent crack formation, such steel parts are quenched very slowly in oils, polymers of high concentration, or gas quenching is used. When bottle with water is not frozen through, cracks do not appear. For real steel parts an optimal quenched layer exists which provides the best condition for intensive quenching and increasing service life of hardened steel parts. It means that  hardened layer of steel parts should be optimized. 

    Maxim Ryzhkov · Ural Federal University

    The developer of low-hardenability steels (Shepelyakovkij) assured, that the optimal hardened layer after quenching seems to be about 10...20 % of the part cross-section. He had some publications in Metal science and heat treatment journal. If you are interested, I can try to look for them in case they are translated.

  • Miranda Vieson added an answer in Polyps:
    Can anybody help with this image?

    I have found it in a rat colon. May be a polyp or an adenoma?. Thanks

    Miranda Vieson · Virginia Polytechnic Institute and State University

    I think you may have picked up a portion of a seminal vesicle (especially if this is a separate piece from the normal colon, which you said is at the bottom of the slide and out of the images).  While the magnification is pretty low, I don't see goblet cells in the epithelial component and the organization of the epithelium doesn't look quite colonic to me.  There also seems to be some bright pink secretory material in the interior of the spaces.  The connective tissue surrounding the structure also doesn't look like the typical two-layered muscularis of the GI tract.  A colonic polyp or adenoma would most likely be present protruding from the mucosal surface and into the lumen of the colon and will have a very similar appearance to the normal colonic mucosa (with goblet cells).  

  • Shaad M Ahmad added an answer in Transgenes:
    Is an overexpression system for Drosophila animals interesting for somebody?

    Recently I developed a way how to increase transgene production in Drosophila animals. This is a side product of my fundamental research and I do not have time for exploring the practical opportunities of this system. At least not now. I wonder if somebody would be interested for joining forces and trying to apply this system for some economical or research purposes.

    The overexpression is very strong - 20-40 times more in mRNA levels as judged from qPCR and Northern. In the attachment you can find daylight photos of flystocks, both of those are expressing mCherry with the use of the same da-GAL4 driver. Left - a conventional construct, right - same with overexpression.

    Shaad M Ahmad · National Institutes of Health


    How tight is the expression with say, a tissue-specfific GAL4, e.g. elav-GAL4, twi-GAL4, tinD-GAL4?  The question here is whether what  you are seeing is a consequence of overexpression in the cells where GAL4 is driving the transgene, or leaky ubiquitous/semi-ubiquitous expression in all or most cells, even the ones where the driver isn't "on".

    If the former, then one can see multiple uses of it in Drosophila, e.g. more effective RNAi, use of dominant negative constructs, rescue assays, FACS-sorting of different cell types, just to name a few.

  • Why is the length change of the arms of an interferometer by a gravity wave not cancelled by a proportional change in wavelength of the laser light?

    A gravitational wave detector like LIGO or Virgo has two orthogonal arms with laser beams bouncing off mirrors that are made to interfere destructively in the intersection of the arms. A gravitational wave will shrink one arm by a (tiny) amount delta(t) and stretch the other by delta(t). The shrink and stretch  vary periodically with a frequency of the order of kHz to be detectable. One would (naively) expect to get a signal varying like

    sin(4delta(t)/lambda_{laser})  = 4delta(t)/lambda       

    (the factor 4 comes from the two arms each giving a contribution delta and and the two armlength the light travels as it bounces back from the mirror).

    However, what one really measures is the difference in wavenumber (i.e phase) between the standing light waves in the two arms.  My problem is that the gravitational wave also changes the propagation of electromagnetic waves, and I don't see why the wavelength in the two directions are not shrunk and stretched by the same proportion (at least to first order which is the only thing one might hope to be measurable) so that if we continue this line of thought, the wave numbers in the two directions of the beam line should actually be the same (to first order) as without the GW and no interference signal would be detected. Note that in the kHz band the wavelength of the GW is of the order of 300 km so is essentially constant over the whole (km's sized) detector. 

    Rogier Brussee · Hogeschool van Utrecht

    @Dick Vestdijk, thanx for the reference, but the authors don't actually touch on this point. 

  • Hello, could anybody point out studies regarding how to measure the IT department personnel capability?

    I am trying develop a set of metrics for IT departments in organizations? First, I would like to investigate the personnel capability?

    example of a solution developing team

    Personnel capability in the test team can exceedingly impact on software testing performance and leads to success or failure of the project . A quality tester with high capability can help project save a lot of cost and time. Moreover, they exert high impact on the quality of product and process delivered. To improve testing personnel quality, the executives have to continuously support them for knowledge management by knowledge sharing, internal training, and external training

  • Fatiha Chigr added an answer in IGF-1:
    Can insulin-like growth factor-I receptor inhibitor be injected into the hippocampus or lateral ventricles to assess hippocampal neurogenesis?

    I am planning to perform a pharmacological study to assess hippocampal neurogenesis via IGF-1 receptor inhibitor. But most studies were performed  in vitro or in vivo (systemic). So whether this inhibitor of IGF-1R (such as AG-1024 or picropodophyllin) can be  intracranially injected by stereotaxic localization and what is the optimal dose? Thank you!

    Fatiha Chigr · Université Sultan Moulay Slimane

    Try to administrate insulin-like growth factor-I receptor inhibitor in lateral ventricle. Normally, you will act on neurogenesis in SVZ.  At what level this influences neurogenesis in hippocampus, is an open question.

  • Mohsen Hojat added an answer in Education Research:
    Any recent studies on student-teacher evaluation and its impact on teachers' performance?

    I am conducting a small scale study on the effectiveness of student-teacher evaluation. Does students' evaluation give an objective image of teachers' performance? 

    Mohsen Hojat · Jahrom University of Medical Sciences

    hello dear collegose

    if you search in google scholar

    you can see 30  farsi article that you cansee english abstracts

    key words is(ارزشیابی  استاد توسط دانشجو)

  • James H Adair added an answer in Borohydrides:
    Why gold nanoparticles shows negatively charged at pH 7 in buffer solution?

    I am trying to synthesize positively charged gold nanoparticle? When I used Borohydride or citrate as a capping as well as stabilizing agent the surface charge of the gold nanoprticle is negative at pH 7. After that I used amino acid as a stabilizing agent as well as reducing agent and getting positive charge (+10 mV) at pH 5.9. But when i am adjusting pH 7 it is showing negative charge (-2 mV ) as by Zeta potential analyzer. My main aim is to synthesize positively charged gold nanoparticle at pH 7. Can anybody suggest me why it is happening and would be thankful for your suggestion.

    James H Adair · Pennsylvania State University

    Citrate, of course, specifically adsorbs to the gold nanoparticles.  Citrate adsorption can confound the adsorption of any other ligand you add because of the very large pK of adsorption for the citrate.

  • David Collins asked a question in Spirituality:
    A "philosophy" approach to defining spirituality?

    I have a student interested in comparing different fields' definitions of spirituality and/or approaches to defining spirituality. She's hoping to incorporate a "philosophy" perspective. Broad topic, obviously, but any suggestions for a representative article?

  • Saeideh Hosseini added an answer in Kesterite:
    Why are kesterite materials used for solar cells applications?

    In CZTS structures there is three type of structures available.

    Stannite, Wurtzite and Kesterite.

    Among these three, what is the reason we are giving preferences for Solar cells applications?...

    Saeideh Hosseini · University of Zanjan

    you can see the attached links

  • How do you utilize Symbolic Interactionism as a theoretical framework for qualitative research?
    SI may be a productive framework but exactly how does it frame data collection and analysis?
    Bruce Fortado · University of North Florida

    David: Thank you for giving me a chance to either (1) learn from my mistake, or (2) explain myself more fully.  You have a concern about my characterization of the Iowa School. It is probably best to go directly to what Kuhn and McPartland (1967-and earlier 1954) had to say.  Kuhn and McPartland (1967: 120) explain "The first obvious step in the application of self-theory to empirical research is the construction and standardization of a test which will identify and measure self-attitudes."   On Page 121, the reader learns about several prior pilot studies that used a different approach. On page 122, we learn more specifics about this effort.  The 288 students were given 12 minutes, and in their instructions they were told "Don't worry about logic or importance. Go along fairly fast, for time is limited."  They were given a one page sheet with twenty numbered blanks and the simple question "Who am I?"  On page 128, we learn they were also asked "What is your religious affiliation or preference?"  The list of twenty items was subsequently checked to see where religious affiliation was listed.  If it was first, this would be given a 20, and a declining scale was used going down to zero for not mentioned (p. 130).  On page 131, in what is described as a completely independent operation, the reader learns the students were also asked "With what groups do you feel most closely identified?" or "I am proudest of my membership in _____________."  On page 133, a set of potential questions for the future are listed. Interested people can look into the Guttman scale analysis, inter-rater reliability data, test-retest information, and the discussion of validity.  

         Let me share a couple of my thoughts in closing.  I am not aware of anyone from the University of Chicago tradition or any other interpretive tradition who would conduct observation or an in-depth interview for twelve minutes.  Many field researchers would not agree with the interpretation that what was first observed should be given a weight of twenty as religion was, and a declining score for each placement below this.  Many field researchers believe it takes time, and the development of a relationship, before many important things are shared.  Giving one sheet with twenty blanks is different from using twenty pages, or two hundred pages. In employment interviewing, an applicant might be asked to "Tell me about yourself." Most people give a very brief answer, perhaps of less than a minute, and cover two to four subjects.  Over time, questions like this have been judged to be poor ones that provide little useful information.  Some candidates are taken off guard. Few would offer up weaknesses or faults for fear of not getting a job.  In sum, the approach used by Kuhn and his associates had a structure that was very different from observation and in-depth interviewing.

         In view of your reaction, I wondered if you might be a follower of the Iowa School. If so, it is very nice to meet you.   I am a field researcher.  I really prefer doing fieldwork than spending too much time on theoretical debates.  If my poor choice of words offended you, I apologize.

  • Stanisław Deja added an answer in DNAse:
    Are you familiar with LC-MS metabolomics from formalin fixed tissue samples?

    How would one go about getting rid of the formalin fixation to extract metabolites from lung tissue samples? I know one can use 80% MeOH on really thin slices, but I have bigger pieces - which, when fresh, I usually treat with collagenase and DNAse for extract the metabolites. 

    Stanisław Deja · University of Texas Southwestern Medical Center

    Dear Dirk,

    You might be interested in this publication: "Metabolomic Profiling from Formalin-Fixed, Paraffin-Embedded Tumor Tissue Using Targeted LC/MS/MS: Application in Sarcoma"


  • E. Albertin added an answer in Nuclear Fuel:
    What are the materials usually used for a cascade to store used Zirconium rods containing spent nuclear fuel?

    Temporary cascade with life up to 500 years before recycling of the nuclear fuel.

    E. Albertin · Instituto de Pesquisas Tecnológicas

    Check the ref  in  http://rampac.energy.gov/docs/nrcinfo/NUREG_4363.pdf

    and also  http://www.posiva.fi/files/281/Posiva2005-02web.pdf

    Both describe canisters made of ductile cast iron .