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  • Verónica Caridad Rabelo added an answer in Questionnaire:
    Do you know any websites that contain adapted/validated instruments, questionnaires, scales?

    I got the task to prepare a report on adaptation of scales, but I can’t find any websites/databases where the lists of adapted scales would be presented in different languages in a more or less comprehensive way. In this case, I am most interested adapted instruments for stress, mobbing, nepotism, ostracism.

    Verónica Caridad Rabelo · University of Michigan

    Two resources come to mind:

    1. Searching in a dissertation database (e.g., http://www.proquest.com/products-services/dissertations/Find-a-Dissertation.html) ... oftentimes scholars revise/adapt scales for their dissertation studies, and almost always include full copies of the scales in the appendices.
    2. Searching in measurement databases. Here's a great resource from the University of Michigan: http://guides.lib.umich.edu/tests

    Good luck!

  • Tausif Alam added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Tausif Alam · University of Wisconsin–Madison


    "it depends on level of thinking, on what do You want. Marc promotes us to think very deep."

    Some times another phrase comes to mind: making a mountain out of a molehill.  ;)

  • Timur Bulgakov asked a question in Zoning:
    Fungal specimens from Russia 2015

    During spring April-June 2015 I had collected many microfungal specimens (over 200), some smut and rust fungi and downy mildews from Rostov region (Southern European Russia). Also my colleague had given me about 100 analogical specimens from Arkhangelsk region (Nothern European Russia, White sea coast of Russia) and Krasnodar region (Caucasus, Black sea coast of Russia) some days ago.

    If you or your colleagues are interested in these microfungal specimens, we are ready to send them (gratuitously) to you for any scientific research.

    Excuse me, but for some reason I did not have time now to make a detailed check-list and to identify all specimens (especially because some of them maybe new species or needed in eutypification). Here are just basic taxa. Perhaps I accept new taxa in the list. You can ask me about anything, to clarify the information.

    Please, see Attachment.

    Some photo of infected plants (the specimens collected by my colleague Gennady Okatov) from Russia you can find here

    http://www.plantarium.ru/ page/gallery/of/664.html

    Preliminary taxa check-list of fresh specimens from Russia collected in 2015 (Archangelsk region – conifer forest zone, Rostov region – steppe zone, Krasnodar region – subtropical forest zone)

    Also I have large private collection with old microfungal specimens (2005-2014) from Southern European Russia (include plant pathogens and saprobic species). I can send them also if you need.

    General check-list is here (book)


  • Verónica Caridad Rabelo added an answer in Masculinity:
    Does anyone know about a measure of masculinist beliefs and attitudes?

    I am interested in people's beliefs and attitudes regarding masculinism, and I am having a hard time finding a measure of such concept that could be used in standard research questionnaires. Any suggestions welcome!


    Verónica Caridad Rabelo · University of Michigan

    Jacques, I'd be happy to help any way I can! I'm working on a few projects related to masculinity, so I can relate to the overwhelming + disjointed nature of this subfield of research. It's an interesting and curious mix of sociology, feminist/queer theory, and social science... and it can be difficult to figure out how to jump in!

  • Wayne Carmichael added an answer in Marine Algae:
    Can anybody suggest the preparation steps (stock prep. n mixing) for f/2 medium for culture of marine algae?

    As the different stocks are prepared and mixed to prepare the final media, the trace metal solutions are not autoclaved rather filter sterilized. But i have autoclaved it and may be the sodium molybdate component is not behaving properly! plz suggest the exact steps anybody who has workbench knowledge in this.

    Wayne Carmichael · Wright State University

    See attached recipe.

  • Adilya Rafikova added an answer in ROS Measurement:
    What dye is the best to use to detect ROS levels in C.elegans?

    I have been using DCFDA in 96-well plates, but I'm getting high background reading, and I'm also not convinced with my confocal images. I'm debating between MitroTracker Red CMXRos and CellROX Red Reagent. I'd appreciate any feedback and links to protocols. Thanks

    Adilya Rafikova · York University

    Thank you Nai-Kei Wong, but do you have any suggestions/preferences for the dye to use?

  • Ismael Matos da Silva added an answer in Agricultural Economics:
    Which theories support farmers buying behaviour and also factors influencing farmers buying behaviour towards agricultural inputs?

    i am totally confused which theories will be applicable or supports to identify the factors that influence farmers buying behaviour towards agricultural inputs?

    Ismael Matos da Silva · State University of Pará

    Dear researcher. look at the attached book can help you.

    Best Regards

  • Danjuma Aliyu asked a question in Papers:
    What are the criteria of determining quality of published papers?

    How can we determined the quality of published papers. 


  • Stanley F Fox added an answer in Lizards:
    I'm conducting a tail autotomy experiment on western fence lizards but they refuse to drop their tails for me. Tried forceps and fingers. Suggestions?

    I am trying to induce tail autotomy at around 15 mm posterior to the vent. The lizards will try to run from me when I grab there, but they will not drop their tails. I've tried lifting them up to let them hang, I've tried prodding them with a paint brush (which I use to get them to sprint for sprint speed trials), and I've tried applying gentle pressure. They have no interest to voluntarily remove the tail. Hoping someone can give me some tips as I'm under a bit of time constraint to get them back into their home ranges. Thanks!

    Stanley F Fox · Oklahoma State University - Stillwater


    Also, make sure the lizards are very, very warmed up.

  • Bahavan Palani added an answer in Polymer Electrolytes:
    How can I prepare the polymer electrolyte membrane sample for taking TEM studies?

    Dear Researchers,

    I prepared polymer electrolyte membrane samples. Now I want to take TEM  studies for my PEM samples. So, I need information about the sample preparation to TEM analysis. How to prepare the same?

    Bahavan Palani · University College of Engineering, Anna University, Dindigul

    Thank you Sir for your response. It may useful for me

  • Zineb Ammor asked a question in Lacan:
    I want to study Lacan theories,what should i read first ??

    I am new to psychosnalysis of Lacan , i want to study it well because i hear it takes a lot of time to understand , what are the easiest topics he talks about, do you have any websites or books to suggest where i can find analysis of  his theories??

  • Sima Mortazavi added an answer in Primer:
    Could anybody help in interpreting an abnormal qPCR melting curve for CD34 primer?

    I've got a melting curve showing tow peaks (attached file), a small one before the main one, which is seen in 3 cell lines very similarly while absent in the NTC (no template control). The problem that, the amount of detected gene expression is very low using this primer in a CD34+ cells. Is it necessary to change the primer? and is the CD34 gene is expressed in very low amount? Thanks.

    Sima Mortazavi · University of Saskatchewan


    Try to optimize your primers condition or as Iftikar said it may be because of low templates concentration and add more templates. Best.

  • Gert Van der Zwan added an answer in Stern-Volmer Plot:
    What are the possible reasons that the rate of stern-volmer plot depends on the donor concentration?

    Based on the stern-volmer theory, in the slope of F0/F versus [Quencher] there is no term for donor concentration. I'm wondering, what could be a possible reason that this slope changes by the concentration of the donor? How this could be happen? 

    Gert Van der Zwan · VU University Amsterdam

    Concentration of A seems low enough if the nanoparticles are distributed evenly. Did you check linearity of the fluorescence in the concentration range you mention? Could you have clustering of the nanoparticles? Are you sure you are dealing with dynamic quenching and not with static quenching? If the organic molecules attach themselves to the nanoparticles SV would possibly not apply. In that case the so-called modified SV equation is often used which accounts for complex formation. Temperature dependent measurements could help you figure this out, as well as combining static experiments with time resolved fluorescence lifetime measurements.  I attached a paper in which similar effects were measured. They don't give the expression for modified SV, so I attach one of my own papers which has the expression (eq. 1).

  • Carl Manner asked a question in Platypus:
    What methods for seeding 3D cultures into plates with narrow wells are most effective?

    I'm working on conducting an invasion assay using an assay kit by platypus technologies (linked below). I'm having several problems, but my primary concern is rather mundane - pipetting the collagen matrix accurately to the bottom of each well without introducing bubbles. 

    Basically, I have a 96 well plate with stoppers inserted into each well prior to seeding. The space between the stopper and the well, through which my collagen matrix and cells must be dispensed, is quite narrow. In order to get the assay to work, I need to get 20uL of cells suspended in collagen matrix through this space to the bottom of the well. 

    I tried to pipet the matrix/cell suspension using slender tips, as suggested in the manufacturer protocols, to little avail - it's simply too viscous. I tried multiple methods for this - reverse pipetting and regular pipetting, using slender and gel loading tips, using regular tips, and using a repeat pipette with combitips. None of this is working out for me. I wound up seeding my plate by hand using a syringe and 16ga needle, but obviously this introduces a lot of variability in volume which I would like to eliminate the next time I attempt this protocol. 

    Using the slender tips prevented uptake of the (incredibly viscous) matrix - the tips simply won't fill. Using regular tips and combitips prevented access to the bottom of the well (the space between the insert in the wells of the plate and the well walls is rather small). Wide bore tips will not fit through the seeding port. 

    I would vastly prefer to be able to use a repeat pipettor or a multichannel pipettor for this work. If you have a suggestion on how to accomplish this, please let me know. 

    It seems to me the easiest way to do this would be to attach a 16ga needle to a combitip for the repeat pipettor, alas, I haven't been able to find a combitip with either tip narrow enough or a luer lock onto which I can attach a syringe. 

  • C.A. (Kees) Kan added an answer in Broilers:
    What are the technical points in feed choice test for broiler?

    I want to know more about feed choice test for broiler chicken, what is the ideal age for performing the test and what is the best feed trough (two or three troughs contains the feed or one trough divided into partitions) 

    thank you

    C.A. (Kees) Kan

    I would execute the test starting at about three weeks of age. Any low performers can then be selected out already.

    If you divide the feed trough in different compartments, make sure to have replicates of the same feed at different places in the large trough. Otherwise the placement of the feed might be of (major) influence.

  • Prabhat Chandra Mondal added an answer in Gynaecology:
    Which will be the best surgery for III degree UV prolapse in a 30 year old woman who has completed her family and has a big hypertrophied cervix?
    Prabhat Chandra Mondal · Bankura Sammilani Medical College

    Uterus is suspended from behind by uterosacral ligament. Proximally by pubocervical ligament and laterally by cardinal ligament. It is level one support. Direction of vagina during erect posture and nerve supply to levator ani muscle are very important along with length of genital hiatus. Weakness, damage to nerve supply of levator ani muscle are the main culprit. Until or unless US or cardinal ligament gets traction they usually does not lengthen. Whatever the procedure or material, level one and two have to be reconstructed. Either hight US suspension or sacrospinous suspension is essential.   

  • Elizabeth Frayne added an answer in Mitochondrial proteins:
    How do I optimize the expression of unstable protein?

    I have been trying to express a mammalian mitochondrial protein that is ~100kD.  The gene is in the pET47b vector and I have been using the Rosetta2 (DE3) strain.  I have done SDS-PAGE/westerns to confirm expression.  My problem is that the level of expression appears to be fairly low (only have bands on gels/westerns, not the typical blobs from over expression that I am used to).  I have been trying to work out a purification but I just don't seem to get enough from 3 L of culture to have much left after 2 columns.  I believe this is a problem with the protein stability because: 1) When I express at 18C, I seem to get higher expression than when I express at 37C. 2) The protein does not seem to be insoluble. I've checked membrane fractions of larger growths and, while a band appears on western, it is much less than the soluble fraction. 3) A synthetic version of the gene has recently been made to optimize the codons for E. coli.  Expression results are the same. (did not expect this to have much of an effect in the Rosetta2 strain).   

    Does anyone out there have experience using strains that specifically help protein stability (preferably one that will allow pET vector expression)?  Any other ideas?     

    *Protein band in SDS-PAGE gel is located almost inline with the 3rd MW band from the top (left lane). 

    Elizabeth Frayne · University of Phoenix

    Just to be sure I would compare the stability of your protein or a protein in minimal media vs the other medias. I can send you some material later next week. Please email the address info to efrayne@verizon.net.

  • L. Frankfurt added an answer in Elementary Particles:
    Do photons interact with gravitons?

    The graviton is a hypothetical elementary particle that mediates the force of gravitation in the framework of quantum field theory. If it exists, the graviton is expected to be massless and must be a spin-2 boson. The spin follows from the fact that the source of gravitation is the stress–energy tensor, a second-rank tensor. But by no means is it universally accepted.


    But there are many articles about the interaction between Photon and graviton or graviton-photon scattering.



    How can graviton's mystery be solved?  Should graviton be detectable or like photon (same as photoelectric effect) be able to explain the physical phenomena?

    L. Frankfurt · Tel Aviv University

    Graviton-photon interaction unambigously follows from energy-momentum conservation. cf.  short paper of S.Weinberg published many years ago. This interaction is relevant for  change direction of light near heavy stars etc.-prove of equivalence principle..

  • Timothy Bahry asked a question in PRINTS:
    Would life be easier for left-handers if mirror writing were accepted by society?

    Some left-handers are constantly suffering from having uncomfortable writing, pressing against binder rings, and smudging pencil lead. I think to solve that problem society should start accepting mirror writing, though they should not force left-handers who are used to writing normally and don't want to mirror write to do so.

    I think it's possible for that change to get made in a way that's makes it an extremely small burden to adjust to learning how to mirror read as follows:

    • A law gets made that past some future date, all bosses must accept mirror writing in a job and all teachers and university professors must accept mirror hand written and mirror printed assignments, as well as printing 2 stacks of tests for students to come and take themselves, one of which is a mirror printed stack. A teacher should however be allowed to say to a student that their mirror writing is too fast and sloppy to be legible and they need to mirror write slower. To make it easy for people to rapidly improve their mirror reading skill to get the burden of adjusting to mirror reading over with, there will also be a law that for all books that get produced, their mirror image will also get produced and be available to buy online at https://www.chapters.indigo.ca/en-ca/ and more inverted copies will get produced before they run out, not after. There will also be a law that all new laptops must have an option for inverting the screen.
    • There will be a newspaper ad, YouTube an, and TV ad linking web pages each of which teaches how to do one of the following things: rapidly adjusting to mirror reading, mirror printing, and quickly gaining the skill to mirror write when you already know how to write normally. There already exists a web page teaching one of those 3 tasks at http://word.tips.net/T001475_Printing_a_Documents_Mirror_Image.html

    If someone complains to the government that it's too much burden to adjust to mirror reading so mirror writing should not be accepted, the government could respond by saying something like "If you're going to make the choice to cause your own long term problem in your slowless to adapt to mirror reading by choosing to read normally for immediate convenience when ever you can, then don't you complain that we caused you that problem by making society accept mirror writing."

  • Daniel William Magomu added an answer in RNA Extraction:
    If I open the RNA later bottle out of laminar flow it can harm my future analysis?


    I would like to know if there is any possibility of RNA later contamination if I open it out of laminar flow. We proceed all cares during the RNA extraction, however we opened the RNA later bottle out of laminar flow. We work with liver and adipose tissue to evaluate the gene expression of lipid metabolism proteins. I would like to know if this can harm our future analysis. Thank you soo much.Hi, I would like to know if there is any possibility of RNA later contamination if I open it out of laminar flow. We proceed all cares during the RNA extraction, however we opened the RNA later bottle out of laminar flow. We work with liver and adipose tissue to evaluate the gene expression of lipid metabolism proteins. I would like to know if this can harm our future analysis. Thank you soo much.

    Daniel William Magomu · Medical Research Council / Uganda Virus Research Institute

    H Ellen,

    Do you reconstituting it from outside.., if so, then its unsterile and that as well applies to when its diluted. Am afraid that molecular work s too sensitive since genes are found anywhere!

    However, if it was in seconds outside the cabinet,then its safe. But if you happened to use it , even if it were only one sample, because l also use RNALater for storing my samples for further genomic work.

  • Attila Havas added an answer in Co-creation:
    I am interested in finding out how firm conclude what should be co-created with customer and what should be done in house?

    We are interested in upto what extent its acceptable for the firm to allow its customer to be engage and why

    Attila Havas · Hungarian Academy of Sciences

    The classic pieces are by von Hippel on the role of users, and since then there is a huge body of literature in economics, sociology and management of innovation.

    But don't search for a single answer ("the" answer): firms are heterogenous and even the very same firm is likely to behave in different ways, depending on the innovation project itself, or the period, in which you analyse firm behaviour. 

  • Nai-Kei Wong added an answer in Endothelin-1:
    Has any one tried to induce Hypertrophy in mouse neonatal cardiomyocytes and measure increase in cell area?

    I have been using primary cultures mouse neonatal cardiomyocytes (NCM) to study hypertrophy. However, the conventional ways of hypertrophy induction (e.g. by catecholamines, Angiotensin II or Endothelin-1) were previously shown to have very subtle effects in mouse compared to rat NCMs (Deng et al., Circ Res. 2000;87:781–788.). I have personally noticed this, and the best results I got were when I used angiotensin, but yet in very high doses (10 -50 micro M) for 48-72 hours. Increase in cell size, being a widely accepted marker, was not more than 10-15%. Moreover, it was shown that mouse NCMs undergo spontaneous hypertrophy without an inducer. Nevertheless, unlike the cited paper, some papers have published better results of up to 1.5 times increase in cell size. I was wondering if there are some tricks that I can utilize to get a more prominent effect.

    Nai-Kei Wong · The University of Hong Kong

    There are a few points to note. 

    First, there are multiple forms of starvation as a model, as you know, which is intimately linked to autophagy signaling. Serum starvation is one form of course. 

    Second, in my limited knowledge, I came across experts saying that oxidative stress cannot be easily assessed by a single or even a few markers -- e.g. measuring ROS levels alone.

    A frequent and  quite reliable cell stress index is mitochondria morphology and its famous fission/fusion dynamics. You can check the literature easily. Increased fission under stress is easily observed in imaging. 

    However, as you know CM has "static" mitochondria, the effects may be less obvious. 

    In literature, hydroethidine and MitoSOX have been used to assess CM superoxide changes. Beware though that these dyes stain also DNA and fluoresce. Appropriate Ex/Em wavelengths and alternative confirmation assays are needed. 

  • Mohamed El Naschie added an answer in Homotopy Perturbation Method:
    Why when we use Homotopy Perturbation Method for solving nonlinear PDEs, at increasing time, approximate solution away to exact solution?

    when increase time will increase absolute error.

    Mohamed El Naschie · Alexandria University Alexanderia Egypt

    dear friend-  I am serious that you should ask prof je= Huan He..... he will answer you....he is a nice modest man

  • Attila Havas added an answer in Diffusion of Innovation:
    Is Diffusion of Innovations [Adoption Studies] a discipline?

    Diffusion of Innovations (not sure if its an established discipline), what does it entails and the opportunities available for someone who have done it. 

    Attila Havas · Hungarian Academy of Sciences

    You seem to be interested in sociology of agriculture.

    Good luck with your thesis - don't pay too much attention to the "classification of disciplines". Hope you have a competent supervisor who can direct your attention to the relevant literature, and then the pieces you find most useful would lead to other pertinent pieces.

    Have a look at the publications by SPRU and IDS colleagues who study innovations in developing countries (e.g. Martin Bell), as well as those by Lea Velho and other Latin American researchers.

  • Peter Pediaditakis added an answer in Incubators:
    Are copper-based cell incubators good or bad?

    Does anyone has experience with the usage of Copper-based Cell Incubators? Causing benefits or trouble? Corrosion vs antibacterial effects?

    Peter Pediaditakis · University of North Carolina at Chapel Hill

    All incubators I have seen in the last 20 years have had a stainless inside not copper.  I have seen some with  copper trays but not a copper container. 

    My personal opinion without ever looking into heavily is that it will not make a difference in your contamination rates.  Most problems with contamination arise from poor technique or poor maintenance of the incubator.    The best solution I have seen is with the ability of the new incubators to run a sterile cycle which sterilizes the whole inside including all metal seams.   I once worked in a GMP environment that was regulated by the FDA.  If there was a significant benefit, I am sure the sales people of the equipment would of let us know. (empirical ).

  • Raeesh Muhammad added an answer in 31P MRS:
    What kinds of information can 31 P NMR give me?


    I would appreciate if you could guide me about 31P solid states NMR analysis. I want to measure the P adsorption on calcite crystal (I add P as additive to the crystals precipitation solution and see surface modification).

    What kinds of information solid states NMR can give me? I mean,

    can it tell me binding between P-Ca and strength of the bind?

    amount of P adsorbed?

    configuration of P on the surface

    or it just will tell me there is P or there is not. 

    Can it say P is on the surface or it has incorporated to the crystal structure


    Raeesh Muhammad · Indian Institute of Technology Roorkee

    Hi Taher,

    31P NMR will tell you about the presence of P in material and also will give you information about the environment around the P atom. I mean to say that weather it is bonded to electron withdrawing group or donating group.

    About other thing that you asked, is difficult to predict like strength of the bond, amount of P adsorbed, configuration of P on the surface, surface functionalization with P and crystal structure.

    If you need further help, please feel free to ask



  • Punit R Patel asked a question in IDEA:
    How can improve pagerank using normalized method?

    i want to know normalized method to improve pagerank any idea?

  • Kamal Adhikari asked a question in Cancer Cell Line:
    Can we use MTT-assay for high-throughput screening (HTS) for determing the cytotoxicity of drugs?

    I am curious whether MTT can be use for HTS or not? i need to determine the cytotoxicity of 50 different small compounds against various panel of cancer cell line (7 cancer cell line). Is it feasible to use MTT as HTS? IS there any other cytotoxicity assay to replace MTT and more reliable one.

    I would highly appreciate if someone share some related information.

  • David Calder added an answer in EFA:
    Data Analysis - any Suggestion?

    I am working with my academic advisor in order to conduct the following survey: 25 Critical Success Factors (CSF) related to manufacturing strategy – collected from articles, congress papers, academic books, etc -  are being submitted for volunteers – with professional experience on the subject - to rate these CSF importance for a manufacturing strategy implementation (using a 10 point Likert scale). Moreover, it is also requested another rate – for the same factor - regarding the use/importance of this CSF in their personnal experience.

     The collected data will be “treated” in the following way:

    - MDS (MULTIDIMENSIONAL SCALLING) in order to validate the data;

    - EFA (EXPLORATORY FACTOR ANALYSIS) to identify relationships between the responses;

    - PEARSON correlation coeficiente to identify correlation between the CSF.

    Is there any suggestion to run these statistical analysis? The survey is still running but I started to look for the best (and practical) way to run that out. I tried to use Excel but it seems not to be indicated for that. I’m trying “R” but my learning progress has been disappointing! Any other tool/technique available? Thanks in advance.

    David Calder · University of Dayton

    Augusto, my intent is to use it for data mining. I'm interested to see if it will be useful for reliability & maintainability and sustainment analysis. I see you are with Embraer; I also work within the aerospace industry. I take it you are data mining too?