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  • Doria Christian added an answer in Sarcopenia:
    Calf circumference as a surrogate marker of muscle mass for diagnosing sarcopenia in Japanese men and women ?

    please assist in sending me this journal

    Doria Christian · Università degli Studi G. d'Annunzio Chieti e Pescara

    Hi Jim, try to look at this article!!!

    Regards Christian

  • Does anyone use adenosine deaminase (ADA) as an evolutive marker for multiple myeloma?

    Adenosine deaminase (adenosine aminohydrolase, EC; ADA) ) is a enzyme ubiquitous, widely distributed in human tissues, and common in blood peripheral cells, like lymphocytes, granulocytes and erythrocytes. Serum ADA levels were raised in patients with haematological malignancies.

    Béatrice Marianne Ewalds-Kvist · Stockholm University

    Dear Fernando,

    here is the email address to  Mitch A. Phelps, who can give you an informed answer: mitch.phelps@osumc.edu.

  • Does the linear integer optimization problem attached to this message admits a (simple) solution with polynomial complexity?

    The structure of this problem is similar (not equal) to other problems that admits simple solutions. Maybe, the colleagues of this community could help me in identifying a solution to this problem.

    Francisco Rafael Marques Lima · Universidade Federal do Ceará

    Thank you again for the help. I will search for extensions of GAP problem in the literature. 

  • Dinesh K. Dixit added an answer in Spintronics:
    How to calculate Total emitted output power of an oscillator at a partiuclar dc bias current (I)?

    In my experiment on spintronics oscillators I recorded Power Spectral Density (PSD)/Bandwidth as a function of frequency (using Spectrum Analyzer). I have corrected the background subtraction of our data. I considered data for I_dc = 0.0 mA as the background data. Moreover we have not used any preamplifier except the internal-preamplifier of the spectrum analyzer. As far as I know the gain of internal-preamplifier need not be corrected as it is automatically corrected being internal component of the Spectrum analyzer.For a particular dc current (I_dc), I added up all the PSDs at different frequencies and then calculated emitted microwave power of oscillator for constant (I_dc) by following formula:

    Emitted Microwave Power  = (Total PSD/Bandwidth) * Frequency range

    Am I correct while calculating the emitted power?

    Please give your comments.

    Dinesh K. Dixit · Indian Institute of Technology Bombay

    Dear Prof. Zekry,

    Thanks for your help. Indeed thanks a lot.

    Could you please provide me some reference (text book link or research paper) about power calculations so that I can validate everything before making the final call?

  • How can I use InChI keys to enhance a chemical database? Is there a method to decode them?

    InChI keys are generated using hash functions that are supposedly near impossible to decrypt. I am currently using InChI keys that access a database created by myself to identify and undertake simulations. The database merely uses the InChI key to locate the chemical structure in question. This naturally limits simulations to only those chemicals within the database.

    I was wondering whether there is a method to actually decode the InChI key to obtain meaningful information rather than merely using it as an identifier. Alternatively, I was wondering if there is a method to link online databases to the program to access InChI keys, somewhat akin to the twitter api...

  • Yuri I. Yermolaev asked a question in Geomagic:
    Please, pay attention to a typographical error in abstract of paper by Yermolaev, Geomag. and Aeron., N2, 2014 ?

    See reference: http://download.springer.com/static/pdf/678/art%253A10.1134%252FS001679321488001X.pdf?auth66=1419159717_2fc70b86922149fd1586ded7343d7d8d&ext=.pdf

  • Soh Edwin Mukiawa asked a question in Impress:
    Should articles be review without knowing who and where there are coming from? why?

    The reason i ask this question is because the same article that is rejected by one journal is publish by another. There is even a case were two reviewers of the same journal gives very far apart suggestion,one rejecting completely and the other impress by the work and suggesting modification.Let me know your opinions dear friends.Thank you.

  • Hassan Mahani added an answer in EOR:
    What are the challenges in polymer flooding?

    In fact, I'm looking for any challenges and problems about the polymer flooding (chemical EOR method) that researchers and industry are concerned with them and need to be solved, but nobody didn't research and solve it, yet! 

  • Hassan Zareei added an answer in Factor Analysis:
    Is there any connections between ANOVA and Discriminant Factor Analysis?

    For research in data analysis.

    Hassan Zareei · Yazd University


    i think that ,ANOVA  when used that researcher have one dependent variable with interval scale. but in Discriminant Factor Analysis, dependent variable is nominal scale. also it used in predict of member to 2 or more group.

  • How can I become to discrete the Kullback Divergence?

    I have the Kullback Divergence in its continuous form and I need it in its discrete form.

    Vladislav Bína · Vysoká škola ekonomická v Praze

    The discrete form is analogous: D(P|Q) = \sum_i P(i)  \ln \frac{P(i)}{Q(i)}

  • Brendan Delange added an answer in Colony PCR:
    How long is the initial denaturation step for colony PCR?

    I am performing colony PCR using Thermo Scientific's Phusion Hot-Start II polymerase. The manufacturer's instructions recommend an initial denaturation step of 98C for 30s. Should I increase the temperature or length of this initial denaturing to ensure complete cell lysis, and if so what temperature/time should I use? Thanks!

    Brendan Delange · University of Michigan

    Yup, looks right: pellet cell debris, discard supernatant. The more that I look into colony PCR, and the more steps I add to my protocol, the more that it resembles a spin-column protocol! Since I have the spin-column kits, I'm going to use them for my first sequencing runs, then play with colony PCR to see if I can lower sample-prep costs for upscaling the assay. Thanks for all of the suggestions ya'll :D

  • Behnam Farid added an answer in Phonons:
    Can a phonon make coupling with spin of electron?

    This is concerning spin-spin interaction.

    You are welcome Rai!

  • How can scientific understanding of beneficial soil microorganisms be utilized to increase agricultural production?

    I have read that researchers have noticed significant differences in soil microorganism community structure / ratios of fungus:bacteria in samples of grassland compared to agricultural fields.

    Soil microbiology is a (relatively) young discipline. Are we at the point where we can utilize what we have learned about soil microorganisms to agricultural applications?

    Bernhard Meier zu Biesen · NROs, ACSAD Arab League; ARI Tanzania; Agric. Investm.Ltd.

    Orientations from my side. 1) Soil-scientists can trigger www-based state-of-knowledge conferences, exchanges, blogs, etc. on the potential of beneficial soil micro-organisms for agric. production and biodiversity in general. This can avoid wastig funds for research on issues which are done and can contribute to quick application of promising research-results for a crop-demanding, fast growing world. 2) The Nitrogen-"factories" with / in Rhizobium-bacteria / nodules are well established and in use worldwide; however systematic utilization, application and practice in general plant-production is not yet done. The mineral fertilizer industries / multinational agro-chemical companies will act against such efforts. Still: these types of micro-organisms are not the only ones transforming areal N into plant-nutritents. Contributing to better, systematic understanding of these beneficial interrelations can feed millions and billions. 3) The carbon-dioxide produced by other soil-microorganisms while decomposing organic matter is the chemical pre-requisite for photosynthesis, thus any crop-production. In greenhouses gardeners are "fertilizing" with CO.2  and old foresters were "harvesting" CO.2 by dense enclosure-hedges around tree-plots. 4) The beneficial interrelations of crops in mixed planting (permaculture, organic-farming, etc.) are based also on microbiotic synergies, allelopathys. Systematic compilation of experience from practical work would be an important function of science-workers in this field. 5) The complex diversity in soils, its complexity itself hides still many beneficial relations & dimensions which can boost agric. production. 6) Terra-Preta approach: see the fantastic potential: science can contibute to translate this on large scale into equally fantastic yield-increases.

  • Marc Tessera 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.


    You assert that when I say that 'the concept of 'life' per se is not scientific I make a  philosophical assertion.

    Actually my claim is that the concept of 'life' is not real because it is a historical construction of the human mind.

    My reasoning is the following:

    1. Today it is impossible to have a scientific consensus definition of this concept;
    2. All the terrestrial organisms have been the products of evolution since the beginning;
    3. At the beginning there was the emergence of a process I call level-4 evolution (cf. my 2013 paper "On the thermodynamics of multilevel evolution";
    4. Today most scientists and people consider that the concept of 'life' is real because present organisms are so complex that it seems impossible to envisage that there could have been a direct causal relation with the inanimate world in the past. 

    I think this is a purely scientific reasoning.

    Where do you see a philosophical assertion in such a reasoning? 

  • How can we deposit a thin film of ZnS with thermal evaporation?
    I am working on zinc sulfide thin film by thermal evaporation, but the layers have poor adhesion.
    Benchouk Kheireddine · University of Oran

    normalement ça devrais marcher surtout avec les substrats en verre avec un recuit juste après le dépôt.

  • Gino OLIVE added an answer in Ecosystem Ecology:
    Does a cubic meter of water generate storage in an arid area of 4 kg of carbon through the development of organic matter?

    In the article:Webb W., Szarek S., Lauenroth W., Linerson R.; Primary productivity and water use in native forest, grassland, and desert ecosystems, Ecology, 59(6), 1978, pp. 1239-1247, I understand that a m^3 of water enable storage of 4 kg of carbon, this is call WUE (water use efficiency); am I right? Does any others studies confirm this?

    Gino OLIVE · Lycée des arènes, 31100 toulouse

    Thank you, it helps a lot. My interest is to determine the benefit to irrigate arid zones in the fight against global warming.

  • Mahdi Izadi added an answer in FLUENT:
    Does changing an parallel run on an interconnect system into parallel on a cluster cause increase in error?

    Dear colleagues

    my fluent simulation was running on  station and it was anan UDF based fluent run on an station and change my system to a cluster of stations.

    as computation system has change, my residuals has changed significantly.

    unfortunately I don't no architecture of computer well.

    my question is:

    is parallelization a cause for change in error?(there is an odd experience that run UDF in parallel may cause to a different answer with serial!)

    thanks in advance

    Mahdi Izadi · Iran University of Science and Technology

    Dear Van Marle

    Many thanks ti you for your deep and valuable answers.I always find my answers in your posts.

    So if I use explicit methods I may not have difference in my end result?

    and about  the answer which is created by parallelization, is it a false answer?

    if so what does it mean?

  • When calculating internal consistency (cronbach's alpha) of a scale, can we use multiple data from the same person completed at different time points?

    If a person fills out scale A multiple times, can we include all their attempts at that scale in calculating internal consistency or do we only have to select one attempt of that scale (e.g. the first attempt)?

    Béatrice Marianne Ewalds-Kvist · Stockholm University

    Dear Su,

    You can include all items but they shall be marked with T1 (time 1) and T2 (time 2) and so on. Then write exactly what you did in the method section.

  • Imtiyaz Rather added an answer in Universe:
    Will we ever meet our interstellar neighbours?

    Somewhere 'out there' in interstellar space are people like us, wondering if they are alone in the universe.

    Will we ever meet them or do the laws of physics prevent that ever happening?

    Imtiyaz Rather · University of Phoenix

    There is no such evidence so far of life away from human reach.

  • Ganesan G asked a question in Roughness:
    Why has less focus been given to VPRS?

    Variable Precision Rough Computing is certainly a better tool than Rough Computing. But, I could not find more research papers on VPRS. What are the drawbacks in VPRS?

  • Karl Cammann added an answer in ISO:
    Why are most of the many published point-of-care (POC) or lab-on-chip (LOC) testing devices not available on the market?

    Can it be that the most authors and researchers have neglected and still do not follow the demands of the following ISO norms (with year of coming into effect): 15193 (2002); 15194 (2002); 15195 (2003); 17511 (2003); 18153 (2003) and especially: ISO/PDTS 25680.8: Use of external quality assessment schemes in the assessment of the performance of in vitro diagnostic examination procedures? This European Standard was approved by CEN on 2 March 2004 as EN 14136. Why do most published papers in this area not perform the minimum performance test by taking part in an inter-laboratory trial with real samples and not with pure aqueous solutions without a possibly interfering matrix (e.g., in bio-sensing: enzyme-poisoning, denaturing reagents, proteases, drug-metabolites, etc.)?

    Karl Cammann · University of Münster

    Thank you Mila for your excellent answer; you are completely right!! During my time as Editor-in-Chief of the Elsevier Journal "Sensors & Actuators" we had a rejection quote of > 50% and tried to prevent many of those too optimistic papers. Nevertheless, POC and LOC devices are still much more fashionable for non-analytical chemists, with only minor experience of failing in inter-laboratory comparison studies.  

    Several years ago journals with a certain reputation in the area of Analytical chemistry demanded more than a simple calibration plot in a matrix-free aqueous solution. Either a high quality standard reference material with a similar matrix had to be analyzed or the result of taking part in a robin round study had to be presented to proof that the method delivers the true result (EURACHEM’s “fit for the purpose” concept). The weakest point of most papers is connected to calibration issues in the user’s lab. The crucial topic of the stability of the calibrants (often fragile biomolecules) after the device has been sold is seldom addressed. In addition,  slightly different matrices (POC devices being confronted with the biological bandwidth) demanding a standard addition procedure are seldom considered. 

    Provoking statement: After half a century working in the area of analytical chemistry I came to the conclusion: the more papers on a certain topic, the more problems seem to be exist. My long lasting experience with inter-laboratory comparison studies showed, e.g., those participants using an isotope dilution method achieved most often the best results. Consequently fewer papers concerning further improvements of this method are needed.

  • What is the last WHO updates concerning the safety and dose of domperidon in infants and children and if there are alternatives to treat vomiting ?

    Some pages say that domperidone appears to have many side effects - especially in children. Other papers deny this.

    Béatrice Marianne Ewalds-Kvist · Stockholm University

    Dear Amr Shimi,

    "The uses or indications of domperidone vary between nations. For instance, in Italy it is used in the treatment of gastroesophageal reflux disease and in Canada, the drug is indicated in upper gastrointestinal motility disorders and to prevent gastrointestinal symptoms associated with the use of dopamine agonist antiparkinsonian agents.[8] In the United States domperidone's use is not approved, though patients with various gastrointestinal conditions may qualify for access through the Expanded Access to Investigational Drugs program.# Investigational New Drug Application > Domperidone" http://www.fda.gov. 2014-01-09. Retrieved 2014-06-08.

    Domperidone has been found effective in the treatment of pediatric reflux. However some specialists consider it to be an excessively powerful drug for treating babies with reflux.

    Kapoor, A.K.; Raju, S.M. (2013). "7.2 Gastrointestinal Drugs". Illustrated Medical Pharmacology. JP Medical Ltd. p. 677. ISBN 9350906554. Retrieved 2014-10-31.  (Google Books)
    Rebecca Smith (2014-08-01). "Fear that reflux treatment for babies will be denied under new Nice guidance". The Daily Telegraph. Archived from the original on 2014-10-31. Retrieved 2014-10-31.

    "A review of the evidence confirms a "small increased risk" for serious adverse cardiac events with domperidone use, including QTc prolongation, torsade de pointes, serious ventricular arrhythmia, and sudden cardiac death, the EMA said. They note that a higher risk is seen in patients older than 60 years, adults taking daily oral doses of more than 30 mg, and those taking QT-prolonging medicines or CYP3A4 inhibitors concomitantly.

    The CMDh confirmed by majority the Pharmacovigilance Risk Assessment Committee recommendation that domperidone-containing drugs should remain available and may continue to be used for the management of the symptoms of nausea and vomiting, but that the recommended dose should be reduced to 10 mg up to 3 times daily by mouth for adults and adolescents weighing 35 kg or more. These patients may also be given the medicine as suppositories of 30 mg twice daily.

    The CMDh also agreed that domperidone products licensed for use in children and adolescents weighing less than 35 kg should be given by mouth at a dose of 0.25 mg/kg bodyweight up to 3 times daily, that measuring devices should be included with liquid formulations to allow accurate dosing by body weight, and that the medicine should not normally be used for longer than 1 week."


    25/04/2014. CMDh confirms recommendations on restricting use of domperidone-containing medicines
    European Commission to take final legal decision

    Information to healthcare professionals

    A review of the evidence confirms a small increased risk of serious cardiac adverse drug reactions related to the use of domperidone, including QTc prolongation, torsade de pointes, serious ventricular arrhythmia and sudden cardiac death. A higher risk was observed in patients older than 60 years, adults taking daily oral doses of more than 30 mg, and those taking QT-prolonging medicines or CYP3A4 inhibitors concomitantly.
    The benefit-risk balance of domperidone remains positive in the relief of the symptoms of nausea and vomiting. The available evidence of efficacy was not sufficient to support its use for other indications.
    Domperidone should be used at the lowest effective dose for the shortest possible duration. The maximum treatment duration should not usually exceed one week.
    The new recommended dose in adults (and adolescents ≥ 35 kg where licensed) is 10 mg orally up to three times daily (maximum dose of 30 mg daily). Adults may also be given 30 mg twice daily rectally as suppositories.
    Where suitable domperidone products are available for children, the recommended dose is 0.25 mg/kg bodyweight up to three times daily by mouth. In order to accurately measure doses to paediatric patients, oral suspensions should be given using an adapted graduated oral syringe.
    Domperidone products are contraindicated in patients with severe hepatic impairment, conditions where cardiac conduction is, or could be, impaired or where there is underlying cardiac disease such as congestive heart failure, and when co-administered with QT-prolonging medicines or potent CYP3A4 inhibitors.
    Formulations not consistent with the new dosage recommendations will be withdrawn from the market, as will combinations of domperidone with cinnarizine. The product information for domperidone-containing products will be updated, and a letter will be sent to healthcare professionals explaining the new recommendations.

    Read more: http://www.ema.europa.eu/ema/index.jsp?curl=pages/news_and_events/news/2014/04/news_detail_002083.jsp&mid=WC0b01ac058004d5c1

  • Mazura Mat Din added an answer in E.G:
    How are the numbers in the different formats processed? What are the commonalities and what are the differences?

    I want to know the best available task or paradigm (e.g, selection/comparison task, classification task, naming task, parity judgment task, and ?) to examine these two research questions. Why? 

    Mazura Mat Din · Universiti Teknologi Malaysia

    Basically U need to look into what kind of model or tools used in your research or to analyse your data. Usually it will specify the format required for the analysis. I.e. .csv, rff and so on. Hope this might help

  • Mahran Dawwa added an answer in SDK:
    How can I load the UDF code in ANSYS Fluent?

    When I load the udf file in the software, the following error message appears:

    The UDF library you are trying to load (G:\ship\libudf) is not compiled for 3d on the curent platform (win64).
    The system cannot find the file specified.

    Any suggestion/resource is appreciated.

    Mahran Dawwa · Maritime University of Constanta

    You have to open Fluent with the use of Microsoft windows SDK

  • Chitta Behera added an answer in Time Series:
    What are the different ways to extract dominate frequency component from a non stationary time series?

    Non stationary time series  is one whose mean and variance changes with time.

    Sample of non stationary times series are : exponentially decaying or increasing,   U shape ,mixed of decaying and increasing etc.

    So how to handle these type of problem??

    Chitta Behera · Indian Institute of Technology Gandhinagar

    Thanks a lot for your thoughts. I have attached the snapshot of signal. Here the purpose is to calculate the number of particle and its size from the signal. The signal is generated by by passing the laser light on the sample . if i apply STFT  then what should be the window length? how can i decide that??

  • Can platinum nanoparticles be used in C-C coupling reactions?
    If yes, then how?
    Shaban Ahmed Ali Abdel-Raheem · Agricultural Research Center, Egypt


  • N. Venkatathri added an answer in Refractive Index:
    What is the use of Refractive index ?

    Eventhough molar refractive index is a basic property of a compound like melting point, boiling point, density etc.  However it is not widely used.  Why is it ?

    N. Venkatathri · National Institute of Technology, Warangal

    Probably due to the complication in measurement.

  • Enrique Baleriola added an answer in Social Studies:
    How can we investigate in social studies of science and technology?

    Here is my contribution to this topic, but I want to learn more about it, so all kind of suggestions will be welcome: http://bit.ly/1H3GPbf

    Enrique Baleriola · Autonomous University of Barcelona

    So interesting Mr. Altmann. I think your and my group are in the same path about social studies of Science and Technology. I liked so much your concept of "Reflexive Innovation", undoubtedly, it is a main stream of research about the "seamless web" of Technology, Science and Society. I guess your methodology mode of working is also so interesting.

    If you want, you can also check our website: http://psicologiasocial.uab.es/gescit/en

  • Genevieve Ellen Becker asked a question in Translating:
    Any leaflet, webpage, course that provides skills and tips when writing training materials in English to be translated into other languages?

    I don't want to do the translating. I want my material to be clearer to the people doing the translation - such as avoiding subjunctive clauses or whatever. Mostly in health worker education.

  • Mohamad teguh Gumelar added an answer in His-Tag:
    How to select linker for Affinity Tag Removal?

    I'm a bachelor student and currently studying protein engineering. I want to add his tag on a protein (apoptin) and a cleavable linker between both of them. Is it possible for the linker sequences to affect the structure or even bioactivity of the protein? What should I do to predict the effect and select the best linker sequence for my protein? Your response would be very meaningful, thank you

    Mohamad teguh Gumelar · University of Indonesia

    Thank you Mr.Ravi Kant Upadhyay for the answer, actually I'm asking about the cleavable linker between the tag and the protein. Some prorteases I found have been used for tag removal are enterokinase, thrombine and TEV. Each of them recognize specific amino acid sequence for their proteolytic activity and left different residual amino acid. I want to select the cleavable linker, considering whether it could affect the activity of the protein itself, do you have any suggestion or recommendations? Thank you very much for your help