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  • Is social pharmacy already an important element of the curriculum in arab pharmacy schools?

    Is social pharmacy already an important element of the curriculum in arab pharmacy schools?

    Andriy V. Proskochilo · National University of Pharmacy

    Dear Mr. Mohammed Alshakka.

    In Ukraine, a new curriculum for pharmacy schools includes knowledge of social pharmacy. But since this is relatively new discipline, an education is developing in this field. As far as I know, in our university this discipline has started to teach recently for Arabic students. So let us hope that social pharmacy has a great future!


  • Rene Ahn added an answer in Artificial Intelligence:
    Is there a test for sentience?

    Okay, I am a trouble-maker; I admit it in advance.  But the issue of sentience has occupied a lot of society's attention recently, in books & movies especially, and it's not likely to get less interesting in the future, so let's dig in and thrash out some essentials. 

    Is there any way one could define rational criteria for the sentience of a computer?  A nonhuman organic life form?  A human?   How do you know I am sentient?  How do I know you are?  Personally, I have my doubts about some individuals I have met; you probably do too. 

    If Ray Kurzweil is right, this is not an issue we can afford to neglect until it is thrown before the courts.  Let the games begin! 

    PS: it seems likely that an equivalent Question has been asked already in RG, but I have been unable to find a way to check.  If anyone knows of an existing thread on this topic, please let me know and I'll delete this one! 

  • Peter T Breuer added an answer in Sorting:
    Is there a way to sort a list of {x,y} coordinates based on both x & y values?


    This list has been sorted based on x-values. I can sort them also based on y-values. But I cannot sort them considering both x & y values simultaneously.

    should be arranged as follows:


    u see that neigbouring points allow only one unit of change in either x,y or both

    Peter T Breuer · Birmingham City University

    Weelll, you'll have to point at what it is you don't clearly get, then!

  • Any help with my bacterial transformation problem?

    I transformed the cry2A gene (1.9kb) into the E. coli JAS86 strain using pET32. I got around 32 colonies onto 4 plates of LB medium supplemented with ampicillin (50µg/ml) and kanamycin (60µg/ml). I subcultured the colonies on LB medium with amp and kan antibiotics.

    Next, I plasmid isolated 25 isolates and digested with EcoR1 and BamH1 (single and double digestion). But none of this has yielded me a single plasmid of around 8 kb or two plasmds (5.9kb+1.9kb).

    This E coli strain already contains the plasmid with 7140 bp (being present in upto 5 copies per cell). It seems I am just getting the backbone of the pET vector (around 5-6 kb aftr digestion).

    Can anyone please tell me how can verify my recombinant clone with digestion? Should I repeat the transformation?

    I have uploaded the gel photo after digestion. 1 kb ladder used (200, 500, 1000, 2000, 3000, 4000, 5000, 6000, 8000, 10000bp)

    Reyaz Lone · Periyar University

    i thank you all- sophie ziegler, cara pina, naveenkumar and ugur azizoglu for your suggestion. I will redesign my whole process as per  your suggestions and let you know about the results. 

    once again i thank you all.

  • How do you choose the optimal laglength in a time series?

    There are several criterion for choosing the optimal laglength in a time serie: AIC : Akaike information criterion ; BIC : Schwartcz information criterion ; HQ : Hannan-Quinn criterion ; RMSE : Root Mean Square Error ; MAE : Mean Absolute Error; BP : Bias proportion ; LIK : Log-Likelihood. The discrimination function differs from one to another criterion.

     We can therefore obtain conflicting results.  How to choose the optimal laglength? Are there tests that compare the criteria between them?

    Jamal Bouoiyour · Université de Pau et des Pays de l'Adour

    Many Thanks   to everyone ...

  • F. Leyvraz added an answer in Electrons:
    What kind of electrons, free electrons or bounded electrons, occupy energy level in zone theory of quantum mechanics?

    In the quantum theory of electrical conductivity are considered free and bound electrons.


    F. Leyvraz · Universidad Nacional Autónoma de México

    If the electrons are acted on by a strictly periodic infinitely extended external potential, due to the crystal lattice, and if interaction between electrons is neglected, then all electrons in fact have wave functions that are extended over the whole crystal, as follows from Bloch's theorem. The extended wave functions have a quasimomentum k, and are in a sense deformed plane waves. The energy then depends on k. However, for electrons close to the nucleus (e.g. core electrons), there is almost perfect degeneracy and the electron energies are essentially independent of k. This allows to construct localized wavefunctions. In fact, interaction, as well as disorder, will  localize such electrons, so that the picture presented here is quite academic in that case. However, when the dependence of the elctron energy on the quasimomentum k is significant, we must treat the electrons as free and consider the wave function as exended over the whole crystal.

    This is a rough and ready statement of what I know on the subject. There may well be many more complex issues of which I am not aware.

  • Vishal Bandugula asked a question in Software:
    Converting radiance to reflectance for Landsat imagery?

    Hi all, 

    I  have a landsat image and I want to correct the radiance to reflectance, are there are any freely available tools or software's or can anyone suggest some software's to perform the task? 

    thanks in advance


  • Imre Tóth added an answer in Hydrogen Separation:
    Does being preferred orientation of Palladium (i.e. 111) affect the catalytic activity?

    Does being preferred orientation of Palladium (i.e. 111) affect the catalytic activity, like hydrogen splitting kinetics during hydrogen separation?
    Being preffered oriented or not really important for catalytic activity? If yes, which orientation increases the catalytic activity for Pd?

    Imre Tóth · University of Pannonia, Veszprém

    It is not easy find a reference where explicit stated that 1,1,1 orientation is better for catalyst activity than other orientations (2,0,0  or 3,1,1 for example). Orientations, which provide high contact surface area are probably preferable.

  • What is the simplest way to increase the surface hydrophobicity of TiO2 thin films prepared by the doctor-blading method?

    I would like to functionalize TiO2 thin films prepared by doctor-blading P25 titanium dioxide paste onto FTO glass such that their surface hydrophobicity is greatly increased. Also, I would like to use the simplest reagents possible. Thank you for your help!

    Vamsi Krishna · Indian Institute of Technology Madras

    By adding CeO2 to the P25 paste, you can increase the hydrophobicity of sample (or) by treating formed film by any silylating agent like trialkyl silyl chloride.

  • As a learning objective for teaching, I am trying to dissect the nature of 'humor'. Does anyone have a recommendation for some scientific literature?

    I am looking for characteristics of when humor is perceived as being 'funny', what types of humor exist and how it can be used as a tool in teaching.

    Shanna H. Wielinga · VU University Amsterdam

    Thanks so much for sharing, this has been really helpful!

  • Mary Ann Stepp added an answer in Wound Healing:
    What are the similarities and differences between human wound healing and model systems in mice?

    Is there a good review about the involved processes?

    I suppose in both (adult) organisms, wound healing involves blood clot formation, inflammatory response, growth factor activation of epithelial sheet migration and dermal contraction, re-establishment of an epithelial cell sheet, basal membrane and more or less functional or scarred dermis, and a resolution, in which activated cells go into apoptosis or into a sedentary state. (i.e. http://www.ncbi.nlm.nih.gov.gate1.inist.fr/pmc/articles/PMC2736861/ )

    But I would like to know if mice and human wound healing are thought of as basically the same, and which are the important differences.

    Mary Ann Stepp · George Washington University

    The article Dr. Shinin refers to is just what you were looking for.  My understanding from attending meetings is that skin wound healing people feel that pig skin wound healing is more like human skin wound healing compared to the mouse because of issues related to dermal wound contraction.  The idea I have gotten is that mice can contract wounds really well which makes it harder to study the role of reepithelialization in mouse skin wound healing. 

  • Onildo Marini-Filho added an answer in Moths:
    Does anyone know of a test of LED lamp efficiency to attract moths comparing to mercury bulbs or fluorescent lamps?

    LED bulbs are at the edge of the current lighting technology presenting high energy efficiency and long durability. Comparing LED bulbs to mercury or fluorescent bulbs may be an important technological breakthrough in moth sampling as it would reduce energy expenditure enabling better sampling schemes.

    Performance, cost, durability and enhanced life span are causing UV LEDs to be integrated into a large number of applications. UV LEDs are also much smaller in size and more durable than glass bulbs. UV LEDs are more resistant to vibration and impact, resulting in less product breakage and reduced waste and maintenance expense (Halliday 2010).

    Technical enhancements to UV LED technology added to cost reduction and an increased industry interest are setting a favourable stage to move forward in the application of LEDs to moth monitoring.

    Onildo Marini-Filho · Instituto Chico Mendes de Conservação da Biodiversidade

    Dean, thanks for the references to UV LEDs. I have already included some of the information at the explanation of the question (above).

  • Bela Buslig added an answer in PPM:
    How can fix concentration of sulfur dioxide in 50 ppm in lemon juice?in usual manner concentration is 200-300 ppm.

    200-300 ppm sulfur dioxide is harmful and not suitable.

    Bela Buslig · Florida Dept. of Citrus

    Calculate the weight of added solid potassium bisulfite in terms of SO2 to achieve your desired level in the final volume of lemon juice.

  • What's the best method for evaluation of polyunsaturated fatty acids concentrations in serum? Excluding MS. HPLC or GC?








  • Jean-Lou Justine added an answer in Biodiversity:
    Have you seen this land planarian, an invasive alien species?
    The "New Guinea flatworm" Platydemus manokwari. This species is invasive in more than 15 territories in the Pacific, and has been detected recently in France. It is included in the “100 World’s Worst Invader Alien Species”.
    If you have seen it, especially in Europe, please contact me.
    Jean-Lou Justine · Muséum National d'Histoire Naturelle

    Extremely interesting indeed! Platydemus manokwari has not been recorded in America - yet.

    Do you have photographs?

    Please send them by email to justine@mnhn.fr

  • Nezih Hekim added an answer in Biodiesel:
    Which method can work out detection of consumed glycerol by bacteria via using a simple titration method?

    Hey Everyone,

    I am trying to make my bacteria use glycerol as their only carbon source. I am using E.coli in minimal medium by providing only pure and crude glycerol from the biodiesel industry. They are consuming the pure and crude glycerol that I can understand by looking for growing of E.coli OD600 nm in UV-Vis spectrometer.

    But I have to prove that by concentration difference, so UV is not suitable for glycerol detection and I tried a titration method which I found literature for crude glycerol detection from biodiesel industry (starch and KI as an indicator). However, I couldn't get the true result. I need some suggestions.

    How can I calculate the consumed glycerol by bacteria easily (and cheAply of course)?

    Thanks in advance.

    Nezih Hekim · SANKO University, School of Medical Sciences

    There is simple detection kits like as Cell Biolabs Inc. This colorimetric kit works with minute amount of glycerol in 96 well plate.


    Very cheap, correct and rapid method is to use GC.


  • Preston B Landon added an answer in Colloids:
    Can anybody suggest the easiest method for soil colloid measurement in laboratory?

    Is filter paper applicable for this experiment?

    Preston B Landon · University of California, San Diego

    (1) Try DLS it will give the C.V., (2) Electropharisis, (3) SEM and counting.

  • Massar Alsamraae added an answer in Cryogenics:
    How long can EHEB and NALM-6 cell lines survive when frozen in liquid nitrogen?

    How long do cells stay alive without defrosting them?

    Massar Alsamraae · Northern Institute For Cancer Research

    you can put your cells in liquid nitrogen for ever, but when you want thawing them try to keep them away from stress

  • Janna G Koppe asked a question in Innate Immunity:
    HAve you clinical signs of a depressed innate immunity, like more diabetes?

    Influence of innate imunity on the microbioma is supposed to be a cause for the development of diabetes type 1, Wen Li, Ley RE, Volchkov PY, Stranges PB, Avenesyan L, Stobebraker AC, Hu C, Wong S, Szot GL, Bliestone JA, Gordon JI,C.A., 2008. Nature 455, pp. 1109-1113. Congratulations with your excellent paper, thank you Janna Koppe

  • Flavia Delcourt added an answer in Data Structures:
    What is the best way of importing a general XML file into MATLAB?

    When given a general XML file, what is the best way of importing the file's contents into appropriate data structures that are supported by MATLAB?

    Pointers to solutions or m-code are very much appreciated. 

    Flavia Delcourt · Fundação Universidade Federal do Rio Grande (FURG)

    Importing data from Excel can be done using the XLSREAD function, for example to read all data from myfile.xls:

    A = xlsread('myfile.xls')
    Or to only read a specific range from a specific sheet:

    B = xlsread('myfile.xls','Sheet 1','B10:F28')
    More information can be found in the documentation:


    Good luck!

  • Which biochemical parameters are associated with regulatory T cells?

    Just wondering is there anything we can measure in blood that correlates with Tregs number? 

    Todd Michael Brusko · University of Florida

    The gold standard would be the analysis of the FOXP3-Treg Specific Demethylation Region. This can be done from whole blood, without any fractionation. There are published protocols for real-time PCR analysis and it can be done commercially by Epiontis. Surrogate markers such as circulating cytokines are not going to provide the specificity I believe you are looking for. 

  • Where are the philosophers and sociologists of science in the many controversies and social developments around autism?

    There's a lot going on in the so called 'autism world' which could benefit from research and analysis by sociologists and philosophers of science:

    There's been a radical change in the public image of autism, say from 'Rain man' (1988) to 'Big bang theory' (now).

    Since the mid-nineties until now there's been a remarkable emancipation from no voice to many of which quite a few argue autism is not a disease, but a variation within normalcy of people with remarkable qualities.

    The leading (medical and psychological) scientific paradigm of autism as an incurable developmental disease seems to be challenged more everyday by rival views claiming different (partly) curable etiologies.

    Have these (and other) interrelated developments been the subject of study from the above mentioned disciplines? If so, why do they practically seem invisible?

    Flip Schrameijer · www.architecture-for-autism.org

    You're right: my sadness concerns the lack of interest of these disciplines in rapid and important social developments which just happen in front of us.

    Searching 'philosophy of science' or 'sociology of science' on ResearchGate yields ziltch, tipota. As if these disciplines do not exist. Scary.

    Nice piece. I'm inclined to alter it a little so it concerns autism but my conscience won't let me.   

  • Rajat Acharya added an answer in Kalman Filtering:
    Can Kalman filter apply in pixel value to interpolate pixel?

    I want to reconstruct image using Kalman filter. The pixel has three value R, G, B so I dont know how to deal with Kalman filter equations.

    Rajat Acharya · Indian Space Research Organization

    What I understand from your question is you want to reconstruct some portions of the image whose actual data is unavailable to you. I think you need to know the spatial characteristics of your states, which are your pixel values. with this knowledge only you can generate the proper 'State transition Matrix'. If your image has a continuous (linear or nonlinear) feature, then it can be derived from the available portion of the image. Otherwise, it is not possible to do that in my opinion.

  • How do we confirm that a plant encountered is a new species or not?

    Suppose we encounter a plant in an area and going through the published literature or flora of that place does not provide any ample proof of its record. What are the necessary steps that we must take to establish that the plant is a new record or not?

    Subburaman Senthilkumar · St. Joseph's College of Tiruchchirappalli

    Consult with Local Herbarium and later KEW is the easiest way to confirm

  • Why am I having difficulty with obtaining a linear standard curve for an ACC-deaminase assay?

    Hello, I am a masters student and I am working on plant-growth-promoting rhizobacteria. One of the assays that I am conducting is the ACC-deaminase assay. I am following the method and recommendations of Penrose and Glick (2003) (Attached). However, when I try the standard curve, my absorbence results are very low (as compared with the paper) and are also not linear. I am unsure why this is the case.

    The method entails the following: I make a stock solution of alpha-ketobutyrate (100mM) in 0.1M Tris-HCl (pH 8.5). This is then diluted to 10mM with the same buffer. From this I make a series of alpha-ketobutyrate solutions ranging from 0.1 to 1.0 micromolar. The reaction mixture contains the following: 80 uL of the standard solution and 120 uL of the 2,4-dinitrophenylhydrazine (DNPH) reagent (0.2% 2,4-DNPH in 2M HCl). This mixture is then incubated at 30oC for 30 minutes. Afterwards, I add  800 uL of 2M NaOH and mix the solution. I then transfer 200 uL to the well of a microtiter plate and then read the absorbance at 540nm using a microtiter plate reader. For a blank (zero) I substitute 80 uL of the Tris-HCl buffer for the alpha-ketobutyrate solution in the above reaction mixture.

    My first problem is that the blank has an absorbance similar to that of the standard reaction solutions. Therefore after I substract the blank absorbance from the  standards I get very low values (including some negative values). However, the paper states that alpha-ketobutyrate in the range of 0-1.0 micromolar absorbs in the range of 0-1.6 at 540nm. Secondly, there is no linearity in my values, for example, the 0.2 uM alpha-ketobutyrate will have a higher absorbance than the 1.0 uM solution.

    I have tried this twice (using fresh solutions) but I am obtaining the same results.

    I am very unsure of what I am doing wrong, so could anyone who has had experience with this assay please help me out? Please see attached file



  • Lawrence Margulies added an answer in SAXS:
    Can anyone help that why do we use SAXS in analysis nanodroplets in oil in water microemulsion than WAXS?please answer based on Braggs law.

    Can anyone help that why do we use SAXS in analysis  nanodroplets in  oil in water microemulsion than WAXS?please answer based on Braggs law.

    Lawrence Margulies · University of Guelph

    Read these and all will become clear.

    1) O. Glatter and O. Kratky. Small Angle X-ray Scattering. Academic Press,111 Fifth Avenue, New York, NY 10003, 1982.

    2) A. Guinier, G. Fournet, C. Walker, and K. Yudowitch. Small-Angle Scattering of X-rays. John Wiley and Sons, Inc., 1955.

  • Bruce Weaver added an answer in SPSS:
    WHich test should be performed in spss to compare means of different items rather than participants?

    A t-test for independent groups is useful when the researcher's goal is to compare the difference between means of two groups on the same variable. What is the way if i want to compare means of different variables from two groups. 

    There are 15 items in my survey. and i want to comapre means of these 15 items for the results from 2 different countries. Reason is cross countires comparison!!

    Bruce Weaver · Lakehead University Thunder Bay Campus

    Waleed wants to compare 2 countries on 15 different variables.  As Elton says, that sounds like a multivariate test (where multivariate means there are multiple dependent variables).  So I'm curious as to why Elton's response and my earlier response, which also points to a multivariate solution, are getting down-votes.  Can anyone enlighten me?  :-)

  • Where is the intelligence in AI?

    Like many others, I am very enthusiastic about artificial intelligence, but the more I studied the AI, the less intelligence I found in it. What I found was classification, pattern recognition, and regression. Is there any hope for real AI to be developed in the future? Is it still correct to call AI AI?

    If intelligence is a well known thing, then what is the need for multiple definitions? :) 

  • What is the biggest scientific coincidence that you know?
    For me the two more important are:

    1. The phase transition liquid-solid for the water is that the solid state is less dense.
    2. The dielectric screening in metals is such that the Coulomb interaction among the electrons falls at a distance of the Bohr radius.

    The first one has many important applications as the one of allowing the live in rivers during winter or so on. On the other hand, there are also very interesting electric and thermodynamic phase transitions for this material

    The second, thanks to have a so local electric interaction it allows to have almost free electrons at quite high electronic density in matter and therefore to apply theories so useful as the bands in solids. Over all in metals
    Robin Spivey · Bangor University

    Dear Daniel, with regards to your questions:

    (1) I think you mean dark energy here rather than dark matter. I'm not suggesting that dark energy models are wrong nor am I suggesting that the weak interaction is responsible for the accelerating expansion of the universe. What I'm proposing is that this expansion ends with the decay of dark energy (predominantly) to neutrinos about 60 billion from now. I would argue that this decay is not altogether unlikely because the energy density associated with the current phase of accelerating expansion is tiny compared to its value during inflation and so decay to very light particles might be on the cards. Neutrinos are by some margin the lightest fermionic particles we know of. The lowest energy fermionic particle is a nonrelativistic neutrino.

    (2) Agreed, weak interactions proceed very rapidly (neutrino annihilation included). However, that doesn't mean that the events themselves have to be frequent. The internal heating of planets by a neutrino halo could be compared to keeping a cactus alive with a slow drip of water from a huge lake. It can take a very long time for the lake to empty!

    (3) Why dark energy instead of a cosmological constant? The current phase of accelerating cosmic expansion was preceded by inflation, which terminated with the decay of the underlying energy field to particles. If dark energy follows suit and generates low energy neutrinos then it becomes possible to comprehend a myriad of coincidences as being consequences of the biocompatibility of the universe. Also, until the supernova evidence for acceleration came along, almost everyone just assumed that lambda was zero because some small but non-zero value would have to be fine-tuned to 120 decimal places - no plausible mechanism for which has ever been advanced. So it makes far more sense to keep lambda=0 and anticipate that the dark energy driven accelerating expansion will terminate at some stage, at which time one would expect the copious production of matter particles.

    I hope this helps clarify things but do let me know if you have any other queries.

  • Iswariya Venkataraman added an answer in Expertise:
    Expertise in plaque isolation techniques in Alzheimers Disease?

    I am trying to isolate Alzheimer disease specific plaques from frozen brain sections using indirect immunofluorescence. Does anyone know a good solvent/reagent/buffer that can initially solubilize the surrounding tissue around the plaques in order to isolate these plaques alone and then solubilize these insoluble plaques? Does anyone have any other good plaque isolation technique suggestion?

    Additionally, are 70% formic and 2% SDS the only good solubilization buffers used to solubilize insoluble amyloid-beta components?

    Iswariya Venkataraman · EUROIMMUN Medical Laboratory Diagnostics AG

    Dear Santi
    Thank you for your suggestions.
    Yes, mass spec is one of the techniques I would use to characterize the plaques components. However, the whole tissue is giving a lot of non-specific proteins (• Homeodomain protein OTX2, • Phosphatase methylesterase 1, • Tubulin beta-4A chain isoform 3 etc.). Therefore, I am looking for a technique which would enhance or separate the plaque components alone.

    Laser microdissection is my last option (based on the availability of the microscope, resources etc). I have already read in detail the technique in: Curr Protoc Cell Biol. 2009 Sep; Chapter 3:Unit 3.33 3.33.1-33. doi: 10.1002/0471143030.cb0333s44. Therefore, I am trying other basic techniques before I opt for this.