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  • Dragan Pavlovic added an answer:
    Is mathematics a human contrivance or is it innate to nature?
    Do we invent mathematical forms as we need them and then merely discover their emergent properties later? Or are those mathematical forms innate to nature, and are hence discovered rather than invented? Does it really matter to science, which way around we view this? Is it just philosophy or could there be real consequences? https://www.researchgate.net/publication/256838918 http://www.huffingtonpost.com/derek-abbott/is-mathematics-invented-o_b_3895622.html
    Dragan Pavlovic · Université Paris 7, Paris, France; Greifswald University, Greifswald, Germany; European University, Belgrade, Serbia.
    (Sorry Louis, I did not refer to you in this comment. Please do not disappear, since I sincerely intend to disappear.)
  • Handling of anticancer drugs
    I would like to know about the guidlines to handle anticancer drugs in an ordinary formulation laboratory,mostly working on nanoparticles. Can somone give idea about the requirements of lab?
    Giridharan L M · Amrita Vishwa Vidyapeetham
    If your query is just handling, just read MSDS sheet of any drug you handle. In general, always wear gloves, preferably powder-free, to make sure not to contaminate the drugs with the powders in gloves. A suitable mask, assuming the fine drug powder can always form aerosol and you will inhale in that case. Plz note that most of the times, the drugs will be >98% pure, and so, they are too toxic. Most of the chemodrugs are cytotoxic. So, treat it like poison always.Remember, any drug dissolved in DMSO simply penetrates your skin and makes their fine entry with no doubt. So, whenever, DMSO is used as the solvent or co-solvent, by any means, be extra careful. they can also penetrate your latex gloves to an extent. In this case, go for nitrile gloves, which are relatively chemical resistant (although it wont always protect you). Get the knack of handling chemodrugs, you will eventually be an expert in safe handling without even gloves (although I won't advice you not to use!). Always strictly read the label of any drug you handle (photosensitive, hygroscopic, storage temperature, etc) and store accordingly.
  • Mohammed saleem Ali-shtayeh added an answer in Academic careers
    Is a career in academia still a valid choice amid the lucrative rewards reaped by the business people today?
    Academia refers to the people and institutions concerned with teaching and learning involving research and knowledge building. Academics are the most important group of people for the development and advancement of humans and their societies, and for the improvement of the living standards of people at the local, regional, and the global levels. Academics are knowledge builders without which the world would have never been so developed, sophisticated, and prosperous. Academics are credited for the many discoveries that have made the world a better place and life a convenient and enjoyable one. However, academia or a career in academia is no match for the attractive and lucrative opportunities offered by the business world. The modest and somehow the insufficient material gain made by academics might discourage many from starting a career in academia. The great financial rewards and profit opportunities that characterize the business world today raise many questions regarding the validity of starting a career in academia, or staying in the academic field in pursuit of knowledge and discoveries. Therefore, what is your input on a career in academia? Is it still the right choice today?
    Mohammed saleem Ali-shtayeh · Biodiversity and Environmental Research Center
    In Palestine, a career in university academia still a valid choice for many. However, the chances to join such a group are getting slimmer every day!
  • What is your opinion on the prescription of fosfomycin for urinary tract infections in the elderly?
    The SPC/license of fosfomycin in Ireland does not recommend its use in the elderly "due to diminished urinary excretion". What is the experience of its use in other countries, have there been issues regarding poor effectiveness or resistance?
    Elisabetta Costantini · Università degli Studi di Perugia
    I treat only symptomatic patients, I did not understand you were talking about asymptomatic bacteriuria. this is another situation
  • What are the measures and practices that have been implemented in your institution, as a result of the global and national economy setbacks?
    "Underperformance in the world economy was observed across almost all regions and major economic groups" Problems in global economy will surely affect our national economies. What are the measures and practices that have been implemented in your institution as a result of the poor performance of our global and national economies?
    Federico Del Giorgio Solfa · National University of La Plata
    Automakers with production in Argentina (VW, FIAT, FORD, CHEVROLET, TOYOTA, NISSAN, RENAULT, PEUGEOT, etc.) Have experienced the largest growth market in its history . In Argentina , there is no automotive worker who does not have a car kilometer zero of higher gammas. In short , there is not too many consequences of global economic problem.
  • Lars Rodefeld added an answer in Organic Synthesis
    Can anyone help with the bromination of acetanilide by sodium bromate/ HBr in acetic acid method?
    Generally for the bromination of acetanilide, sodium bromate+HBr in AcOH method is preferred because of in-situ generation of bromine and thus handling of small to larger scale reactions. Can the presence of HBr hydrolyze the acetamido group and thus create complications for getting clean 4-bromoacetanilide?
    Lars Rodefeld · Bayer CropScience
    We used H2O2 to oxidize the resulting HBr from bromination to make full use of bromine. Use can use HBr as well, but will have water in the system then and some chance for hydrolysis
  • Lloyd Chauncey Brown added an answer in Aspen Plus
    Is the heat flow from Gibbs reactor the heat of reaction (heating value of fuel) in Aspen Hysys?
    In Aspen Hysys, the Gibbs reactor shows the heat flow. Is this the heat of reaction or the heating value in case of fuel?
    Lloyd Brown · General Atomics
    The term "Heating Value" has a precise thermodynamic meaning, that is, it is the amount of heat released when combusting one mole of a compound at 25C, one atmosphere pressure, with stoichiometric oxygen producing the thermodynamically stable products at 25C, one atmosphere pressure. The heat flow stream from an Aspen Gibbs block, or any other block for that matter, is the difference in enthalpy between the outlet streams and the input streams. If all that occurs in the block is a chemical reaction, this is the enthalph of the reaction under the reaction conditions. If you specify an outlet temperature, the value of the heat flow stream will depend on the temperature. Essentially, you are specifying that there is a heat exchanger included in the Gibbs block by which you are extracting heat.
  • Does anyone have an effective protocol for extracting nuclei from very small amounts of plant tissue (as in small shoot tips)?
    We are examining the potential for DNA damage in individual shoot tips following various treatments in a plant conservation program. We already know of the various kits available commercially and also have seen some published protocols, but these typically require 5g of tissue (which we do not have). We are also dealing with plant tissue, rather than animal tissue, which may introduce additional difficulties. We would be very interested in hearing from others who may have dealt with this problem before. Thanks.
    Saber Sohrabi · University of Tehran
    What is your plant species for nuclei extraction?
  • What is the working or proposed working temperature of Ni-based ODS alloys?
    Presently working on this.
    P. Susila · NIT
    Thank you. I worked on Fe based ODS alloys for my PhD and I would like to know a specific range for Ni based ODS, whether anyone is proposed to use are already using....
  • Singh Yajuvendra added an answer in Dairy
    How do I asses management effectivity of a dairy farm?
    I am looking for critical management issues towards all aspects of a dairy farm, i.e. nutritional management, parlor management, breeding/reproductive management, etc.
    Singh Yajuvendra · Mathura University
    Proper record keeping will only assist you to make a check list and improve it.
  • Are motivation factors for Gen Y, in general, different from those that motivate the earlier generation?
    It has been revealed by research that Gen Y (those born between 1979-1995) has demonstrated a different attitude. On the positive side, the commonality among their habits and expectations are: preference for fast career growth, communication through texting, respect for merit rather than age, sharper ability to grasp things, primacy on work-life balance, and so on. Does it mean that managers will need different sets of abilities to motivate them for higher productivity compared to what they are used to doing for motivation of people from the earlier generation?
  • How do I form an ester using pentadflurophenol? this organic acid also has a relatively non nuclephilic hydroxyl group.
    I need to activate a carboxylic acid
    Teodoro Kaufman · Rosario National University
    This is not an acid
  • Rohit . added an answer in Endocrine Disruption
    What is the best way to extract estradiol and testosterone from fish gonads?
    I am trying to extract testosterone and estradiol from gonads of fish by using cyclohexane and ethyl acetate [1:1], but the yield is low.
    Rohit . · SRM University
    Thank you Safa Moslemi and Andrea Casano.
  • David Canino added an answer in Biometrics
    Which is better for image processing: C++ or Java?
    Which language is best?
    David Canino · None
    C++, surely. Moreover, you can include your C/C++ code in Matlab.
  • How does beauty contribute to truth?
    The history of science witnessed the prevalence of truth - hence, logic - over beauty. Even farther back, that is exactly the history of the Western civilization. A number of justifications have been brought that place truth as a most salient value over and against beauty. One consequence of this is the displacement of art and aesthetics to the backstage. However recently, for instance nurtured by math, beauty has been reckoned a value at least as important to truth.
    Rajat Pradhan · Utkal University
    Thank you very much Lewis Kausel for the info. on Monalisa. I think if one demystifies the portrait, takes out all the (mis-)understanding that has gathered around it, and then looks at it from one's own point of view, one's own idea of what a beautiful female face should be like, with or without the so-called half-smile etc.etc may be recalling Marlyn Monroe or some such nymph to mind for comparison one will surely find Monalisa lagging far behind in terms of beauty. The enigmatic half-smile with a possible pain underneath no way enhances the beauty. This ia very simple deconstruction which any one can do and the mistaken sense of beauty in Monalisa will evaporate. However, this is not to dishearten or hurt any one who finds beauty in it. each one has a right to have one's own idea of beauty. The same does not apply to Truth of course ! Regards Rajat
  • Denny Milakara added an answer in Cognitive
    How did intelligence evolve? In fact why did it evolve?
    An probable explanation can be organisms needed to survive but I think that alone can't be a reason for intelligence to evolve. Something other than survival might have motivated for the evolution of intelligence.
  • Pamela Snyder added an answer in Cancer Biology
    How can I isolate WBC for RNA extraction?
    Can anyone please share a protocol for isolation of white blood cells and extraction of RNA from these cells (RNA isolation from these cells only)?
    Pamela Snyder · The Ohio State University
    we spin down the sample tube, take the buffy coat, lyse the red blood cells and trizol extract. 7.1. Isolation of Cells from whole blood or bone marrow for RNA Extraction 7.1.1. Spin blood tubes in clinical centrifuge at ~800g for 5 minutes. For highest quality RNA this step should be initiated as close to draw time as possible. Prepare a 15ml conical tube for each sample with 14ml of 1X Red Blood Cell Lysis (RBCL) Buffer.. 7.1.2. Remove white cell layer from spun tube with a transfer pipet and add to appropriate 15ml tube. Invert tube several times to thoroughly mix. Let the tube sit at room temperature for 5 minutes. The red blood cells will lyse during this time. a. Some RBCs will be transferred with the WBC layer. These will lyse in the RBCL Buffer. If there is little or no visible WBC layer, take the top of the RBC layer to the 15ml tube, immature WBCs can be in the top layer of RBCs. b. After 5 minutes, if the sample still appears cloudy, let the lysis tube sit at room temperature an additional 5 minutes. 7.1.3. The sample should now look transparent. 7.1.4. Spin the lysis tubes in the clinical centrifuge at ~800g for 5 minutes. 7.1.5. Pour off supernatant in sink being careful that the cell pellet does not slide. Unlysed RBCs may be with the pellet. Unless there are a large number of them, there will be no problem. If unsure about the number of RBCs, lysis can be performed again. Add 1ml 1X RBCL Buffer, gently resuspend pellet and bring volume to 15 ml. Let sit at room temperature again and respin. Again, decant supernatant carefully. Invert tubes to remove liquid. (Leave a small amount of liquid proportional to the size of the cell pellet as you will briefly “flick” the tube to resuspend pellet. This facilitates pellet lysis in the next step.) 7.1.6. Take tubes to RNA bench. Add 1ml Trizol (a mono-phasic solution of phenol and guanidine isothiocyanate) to the 15ml tube and slowly pipet until the cells lyse completely. Larger pellets may require addition of more Trizol – always in 1ml increments. a. If you have a very large cell pellet, work the cells into solution with the volume of liquid not poured off and remove a proportion with a transfer pipet b. Larger pellets may require 2 or more ml of TRIzol Reagent. It is best to add the full volume of TRIzol to the pellet at the same time, as the lysed cells become so viscous that even distribution cannot be achieved once the cells are fully lysed. An overly viscous sample can lead to protein and/or DNA contamination in the RNA, and may require re-extraction. Due to centrifuge requirements, samples with 2 or more ml TRIzol will be aliquotted 1ml to each prelabeled tube. The RNA extraction can proceed with one or more ml of TRIzol lysed tubes. 7.1.7. Transfer the viscous Trizol/cell solution to labeled 2ml flat bottomed Sarstedt tube(s). 7.1.8. The lysed cells may be stored at –20°C to await RNA extraction. The trizol protocol is pretty standard. 3.2.1. Red Blood Cell Lysis Buffer, 10X 500mL reagent [final] 44.95g NH4Cl 1.68M 5.0g KHCO3 0.1M 100uL 0.5 M EDTA 0.1mM Dissolve reagents in 400 mL of CLRW. Adjust pH to 7.3 and QS to 500 mL. Stable for 12 months at +4C. Note that the RBCL Buffer recipe is 10X. Good luck
  • What is the environmental impact of sugar cane bagasse on soil and water pollution?
    I am currently looking into the potential impacts of open field burning /stockpiling and landfilling of excess bagasse on soil and water pollution.
    Amir Sedaghatdoost · University of Tehran
    I agree with Janet. Moreover, several investigations proved that bagassecan be used for water treatment purpose. It also can be applied as livestock food since it has enormous amount of nutrition.
  • ًًWhat do you think about recommendation letters?
    Are hey crucial? Do they represent reality?
    Mohammed saleem Ali-shtayeh · Biodiversity and Environmental Research Center
    Credible recommendation letters can be an important part in the evaluation process. However, in some cases such letters become only a formality.
  • What is your opinion about using the Raspberry Pi camera module with SimpleCV?
    The following tutorial link: https://github.com/OpenLabTools/OpenLabTools/wiki/Using-the-Raspberry-Pi-camera-module-with-SimpleCV , is designed as a first basic introduction to using the Raspberry Pi camera module. However I have no previous experience using this tool. My question is if some of you have any comment about this tool or any option for image processing using similar cards such as arduino, etc.
    Antonio-José Sánchez-Salmerón · Polytechnical University of Valencia
    I have found this interesting link: http://www.raspberrypi.org/forums/viewtopic.php?t=57788&p=435145
  • Is it contradictory to apply ANOVA and an interpolation method (like Kriging) on the same data to show spatial variations?
    Thank you.
    Rene Westerholt · Universität Heidelberg
    You can apply ANOVA if your data fulfill the respective requirements. You need approximately Gaussian-distributed residuals (because ANOVA is based on testing Fisher-distributed values), homoscedasticity within the groups (otherwise the groups are inhomogeneous and you should revise them) and the data should be iid (which means not autocorrelated and equally distributed over your sample area). As Andreas already mentioned, you should not use a full sample after applying Kriging interpolation. This would create an inherent spatial autocorrelation, infringing the requirements. So, if you want to apply ANOVA use some test for normality, assure that your data points are identically distributed and classify them into reasonable classes.
  • How i can use the awk scripts to find the end-to-end delay from the .tr file?
    I have finished my .tcl file for the wireless sensor network based on the UDP, then i tried to get the results from the .tr file using the awk scripts, but i did not got anything, each time it give an error "division by zero" , i tried many time but each time give different error,I have to submit my results in 2 days, so please i need an urgent help? I have attached the .tr file below
  • Mer Mercurate added an answer in DFT Calculations
    Triplet state otp and TD-DFT, can anyone please help?
    I'm trying to work with triplet state transition using Gaussian DFT. My molecule has heavy atoms and is expected to show triplet state absorption bands and triplet state emission. Could you please help me check if the approach bellow is correct. I plan to perform an "otp freq ub3pw91/genecp" job to optimize triplet ground state T0. Then from that optimized geometry, do a TD-DFT with triplet state, triplet transition td=(triplets,nstates=5) ub3pw91/genecp to obtain vertical excitation. "td=(triplets,nstates=5, root=1); otp" job to optimized first excited triplet state T1. Subtract the energy T1-T0 to obtain the calculated emission energy.
    Mer Mercurate · University of Illinois, Urbana-Champaign
    I found papers, where they state: "Thirty-two singlet excited states and eight triplet excited states(43, 44) were determined starting from S1−4(optimized singlet state) geometries;" 10.1021/ja8025906 "Time-dependent DFT (TD-DFT)(14) calculations were also performed to get singlet and triplet transition energies, on the basis of the structures optimized in their ground state" 10.1021/ja4065188 Does it mean that they managed to optimize excited state start from S0 configuration with TDDFT?
  • Seyed M Nouraei added an answer in Lung
    How can I calculate lung age?
    What is the recent formula that can be used for calculation of lung age in smoking and non smoking people?
    Seyed Nouraei · Imperial College London
    Combining PFT with arterial and venous O2 saturation at rest and after exercise like 6 minutes walk could help to estimate the real lung age
  • Should the term 'scene' be reserved for the geographic area covered by a Landsat image rather than the image itself?
    If I tell you that I used 48 Landsat scenes in a study, what would you think I'm referring to: 48 different WRS2 Path-Row combinations, 48 images of the same Path-Row covering several years, or maybe 6 different Path-Rows with 8 acquisition dates each? Although officially 'scene' refers to the individual data frame into which the satellite continuous data streaming is segmented, and thus it applies to the image data, I think we would be better served if 'scene' was reserved to refer to the area of the earth imaged in that path and row. That is, it would be good if there was a consensus that 'scene' is a synonym for 'tile' or 'map sheet' in the context of Landsat, so that folks know unambiguously what I'm referring to when I say that I used 48 Landsat scenes in a study. What do you think?
    Mohammad Firoz Khan · Jamia Millia Islamia
    So you want to destroy art and landscape or general photography as well as drama.
  • How can we find the thermal stability of a mutant protein structure?
    I have many mutant structures of yeast cytosine deaminase, need to find the mutants thermal stability. I actually have Pdb mutant structures and I need to narrow down its number(350+ mutant structures are avaliable with me) before performing wet lab,any suggestions ?
    Jeffrey Brender · University of Michigan
    Thermorank is one i know of http://www.abl.ku.edu/thermorank/index.html Li, YQ; Middaugh, RC; Fang JW. A Novel Scoring Function for Discriminating Hyperthermophilic and Mesophilic Proteins with Application to Predicting Relative Thermostability of Protein Mutants. BMC Bioinformatics, 2010, 11:62. Ranks a series of sequences based on predicted thermostability Experimentally, DSC and activity after incubation at elevated temperatures s your best bet as suggested above
  • What is transflectance in spectrsocopy?
    Hugh Byrne · Dublin Institute of Technology
    See for example "Reflection contributions to the dispersion artefact in FTIR spectra of single biological cells", Paul Bassan, Hugh J. Byrne, Joe Lee, Frank Bonnier, Colin Clarke, Paul Dumas, Ehsan Gazi, Michael D Brown, Noel W Clarke, Peter Gardner, Analyst,134, 1171 - 1175 (2009)
  • Jonathan Edwards added an answer in Mind
    Why aren't scientists not successful in developing a science for consciousness?
    Do we reach God (here consciousness) through ‘gaps’ in the rules of nature or through the rules of nature.
    Jonathan Edwards · University College London
    Dear William, We have a perfectly good solution to the occasional events you describe - amongst perhaps ten billion lifetimes since the late 1800s. People are very often irrational, particularly about fears for their loved ones and coincidences can be expected on a pretty regular basis since there are so many ways they could occur. Hume's explanation for 'miracles' remains good common sense and quite adequate. Moreover, you cannot have a validatable theory for the totally unpredictable since theories are about predictability. Something I found interesting not long ago was a meta-analysis of reports of such 'mysterious phenomena' of a particular type under laboratory conditions. An inverted funnel plot was used. Although it is rarely possible to show that an individual report is 'massaged' the great thing about the funnel plot is that certain patterns of result can show that the majority of a set of reports are 'massaged'. In this particular instance all the reports showed exactly the same small degree of 'effect', despite the fact that conditions varied quite a lot. The only plausible explanation was that researchers were all producing similar results because that seemed the best thing to do. A small effect would be more plausible and many researchers are likely to think that confirming an effect would be most convincing if it was of the same size. However statistics is cannier than that and it says that true confirmations should not look quite the same. The trouble is that if researchers do not know about all the other results they cannot know what there own result should really look like if it is to form part of a bona fide set of results. So the one thing that seems to be consistent about attempts to get consistent evidence for 'mysterious effects' is that the results are consistently massaged. It all looks very unconvincing, and very much in line with Hume. People are irrational - even in the lab.
  • What are currently used product development strategies in UK?
    I am doing dissertation on Product Development and I would like to know some answers from industry experts.
    Federico Del Giorgio Solfa · National University of La Plata
    I understand that should not differ too much from those used in other countries of similar scale industrial organizations. I copy you access to hundreds of papers in the latest issue of design and development of new products worldwide:
    Leading Innovation through Design: Proceedings of the DMI 2012 International Research Conference Ahmed Kovacevic, Akshay Sharma, Alison Rieple, Amy M. Huber, Amy Zidulka, Andrea Crossley Urrego, Andrew King, Andrew T. Walters, Angélica Lascar, Anna Whicher, Antonius H. Van Den Broek, Anuja Agarwal, Aparna Sundar, Arvind Karunakaran, Beatriz Itzel Cruz Megchun, Belal Alsibai, Benjamin Grossman-Kahn, Benoit Thieulin, Bidhan Parmar, Briony Thomas, Busayawan Lam, Cabirio Cautela, Cara Wrigley, Celine Abecassis-Moedas, Christian Bason, Christina Grundström, Christine De Lille, Çiğdem Erbuğ, Claus Noppeney, David H. Gilbert, David Parkinson, Diana Schneider, Erik Bohemia, Erik Hansen-Hansen, Erik Roscam Abbing, Eunkyong Baek, Federico Del Giorgio Solfa, Fiona Sutherland, Frank Kardes