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  • Panayot Tanchev added an answer in Scoliosis:
    Do you routinely use antithrombotic prophylaxis in scoliosis surgery for children and adolescents ?

    This issue is very controversially or undiscussed at all in the pertinent literature. On the one hand this kind of surgery may last for hours, and on the other hand this prophylaxis is not commonly used in children. What is your approach and practical experience ?

    Panayot Tanchev · Medical University of Sofia

    Dear Andrew,

    I have some experience with the perioperative transoesophageal echocardiography (PTE) for cementless or cemented hip arthroplasty. Especially, in case of cemented endoprosthesis there is an avalanche of signals to be detected by the PTE which is explained with the monomers of the bone cement during the process of polymerization. On the other hand, the incidence of clinically manifested PE is relatively rare.

    There are some reports for PE (even fatal) in case of vertebroplasty for osteoporotic vertebral fractures.

    I do not use PTE during scoliosis surgery for adolescents and I do not believe there is a lot of literature data on practicing PTE during placing pedicle screws for scoliosis. 

  • Hatef Farshi added an answer in Simulink:
    How can I design an ANN controller for a matlab simulink?

    I wanna design an ANN controller for AGC (Automatic Generation Control) problem but I don't know how to connect the ANN matlab codes with my simulink.


    Hatef Farshi · Mohaghegh Ardabili University

    ِDear Gerro Prinsloo

    I mean Automatic Generation Control or Load Frequency Control not Automatic Gain Control but thank you very much for your help...


  • Aiman Eid Al-Rawajfeh added an answer in Writing:
    Does writing quality in a first language corellates with writing quality in a second language?

    I am just wondering if ESL learners who write well in their first language will be able to write in the same quality in a second language. Are there any relationships between the writing quality in both languages?

    Aiman Eid Al-Rawajfeh · Tafila Technical University

    I think it has an influence because writing is a "talent". I believe that a person can be good writer in a language even if it is second or third, once he "thinks" by that language; it means, you can not think in your first language and write in the second.

  • Peter T Breuer added an answer in Determination:
    Is there any way to determine the eigenvalues of A ^ TA?

    We know that A^TA is a semi-positive definite one and we want to know its nonzero eigenvalues, and we also have A^2=A.

    Peter T Breuer · Birmingham City University

    Jiming Wu - we know that Ax=x, because x is a 1-eigenvector of A. Hence ATAx=ATx (multiplying by AT ) and  xTATAx=xTATx (multiplying by xT). But the left hand side of that is |Ax|2 and the right hand side is x.ATx. Since Ax=x, the left hand side is |x|2 and the equation says |x|2=x.ATx .

    Because the operator norm of A is at most 1, and the operator norm of AT is the same as the operator norm of A, one has |ATx|<=|x|. One concludes that ATx is a vector of magnitude no bigger than x in some unknown direction, thus |x.ATx|<=|x|2 always. To satisfy x.ATx=|x|2 exactly, ATx must be aligned exactly in the direction of x and be exactly as big as it. Thus ATx=x.

  • Khawar Sohail Siddiqui added an answer in Catalase:
    Why can I not detect a catalase-peroxidase by zymography that I can detect phenotypically?

    I'm able to detect phenotypic differences among mutant strains lacking one or two catalases, but when I try to detect individual catalase activities by zymography after native PAGE, I'm only detecting one band, corresponding to one of the catalases. The other one has been annotated as a catalase-peroxidase, but I'm not able to detect either the catalase or the peroxidase activity after native PAGE. To develop peroxidase activity I've tried different substrates, including DAB, ABTS, TMB and 3-amino-9-ethylcarbazole. but I only detect the positive control (HRP), regardless the substrate employed. Anyone has a clue what's happening?

    Khawar Sohail Siddiqui · King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia

    Use buffers of different pH's. May be the other isozyme have different pH optimum?

  • Shrish Shukla added an answer in FLUENT:
    How do you perform a mesh quality check in Fluent?

    I have done aorta simulations in Fluent for three meshes. How can we say which one has the better quality for my further tests? The results are nearly the same.

    Shrish Shukla · Indian Institute of Technology Delhi

    you can able to do this by grid independent test through this test you can able to judge the best mesh for your problem.

  • Shakir Sk added an answer in Corporate Strategy:
    Can anyone suggest some good research articles on the strategic control of corporation strategy?

    I want to find out how the effect of strategic control on startegy of coorpration , Do you have any suggestions on what (recent) papers would be suitable for this matter?

    I am grateful for any ideas, suggestions, or information that you may have!

    Shakir Sk · British College of Applied Studies


  • Carlos Guedes added an answer in Rhythm:
    What is currrent research on the relationship between rhythm and body movement?

    I'm looking for recent theories & relevant evidence for both my MSc research project and a summative essay. Many thanks!

    Carlos Guedes · New York University Abu Dhabi

    Hi, you can also take a look at my dissertation (2005) in which I do a review on research on this relationship and establish what rhythms in dance may possess musical qualities. This was done with the purpose of designing software that could extract "musical cues" from dance movement. In any case, I cite a lot of relevant research that may be of help to you. The link to my dissertation: http://carlosguedesdotorg.files.wordpress.com/2011/12/mappingmovement.pdf

  • Fatemeh Sadat Sayyedan added an answer in Ceramics:
    How can we synthesize Cerablak?

    How can we synthesize Cerablak?

    Cerablak is a ceramic based on amorphous aluminophosphate.

    Fatemeh Sadat Sayyedan · Isfahan University of Technology

    Dear Lazaro Pino Rivero,

    can you introduce a paper that the stages of producing method is in it?

    Thank you.

  • Can anyone give me the link of a test case for 3D turbulence k-ω model for backward facing step?

    I am working on the testing and validation of several turbulence models on the already developed turbulent code of my project. If anyone can provide me some 3D turbulence k-ω model for backward facing step then it would be very helpful. TIA

    Shrish Shukla · Indian Institute of Technology Delhi

    your question statement is not clear,  you looking for a case file of BFS or a code of k-w model ??

  • Any recent research examining the relationship of personality disorder to the therapeutic relationship?

    Any research on patient personality disorder as it impacts patient-therapist interactions or the therapeutic alliance since 2010.

    For example: Tufekclioglu, S., Muran, J.C., Safran, J.D., & Winston, A. (2013). Personality disorder and early therapeutic alliance in two time-limited therapies. Psychotherapy Research. 

    Adriano Schimmenti · Kore University of Enna

    Thank you, Christopher. An interesting paper. I think Dimaggio and colleagues are right in highlighting the role of alexithymia and reduced mentalization abilities in PDs. Many PD patients-especially those in the DSM "Cluster B"-have difficulties in identifying feelings (first factor of alexithymia) and they often lack of mentalized affectivity, thus their affect tolerance is really low, and this may foster problem behaviors and symptoms that further reinforce their negative feelings.It's like a vicious circle. On a clinical level, I think that projective identification of unrecognized, unbearable states of mind and feelings of confusion and helplessness into the therapist is one of the main problems to address with them, especially in the first stages of therapy, otherwise working alliance will not develop properly, and the risks for acting-out behaviors and even drop-out from treatment may dramatically increase, but I do not know if research exists on this topic (I think not so many researchers/clinicians would be happy to do research on therapeutic failures...).  

  • Barbara Sawicka added an answer in Bacteria:
    What bacteria are associated with ventricularperitoneal shunts in children?

    need to know at least some genus as a guide

    Barbara Sawicka · University of Life Sciences in Lublin

    Staphylococcus aureus
    coagulase-negative staphylococci
    Enterococcus spp.
    Streptococcus pneumoniae
    b-hemolytic streptococci
    Corynebacterium spp.
    Bacillus spp

  • Imre Tóth added an answer in IPA:
    What is the best way to separate IPA + Toluene mixture?

    Feed contains 92% IPA, ~5% Toluene and ~3 % Water and I am operating a Gravity Packed tower to separate IPA + Toluene + Water terniary mixture from top and Low moisture IPA from bottom. I am operating under reflux ratio of 1:5 with reflux rate of 2000 LPH. Still, I was not able to reach my spec of 99% IPA in Bottom Product.

    Imre Tóth · University of Pannonia, Veszprém

    You certainly know the composition of this ternary azeotrope. What is it? Nevertheless, it seems to me from the relatively low boiling point of the azeotrop that repeated simple distillations taking a little (required) initial azeotrope fraction should solve your problem as you have very little toluene and water.

  • Is it possible to have an adsorption system that does not follow Langmuir or Freundlich isotherm models?

    I'm fitting my isotherm data to linearized langmuir and freundlich isotherm models. But they didn't have a good fit with these models. But data showed a good fit with dubinin-radushkevich and Temkin isotherm models is it possible?

    Rasika Eranda Ashoka Dissanayake · National Institute of Fundamental Studies

    I'm fitting both linear and nonlinear equations for metal adsorption on to plant materials.

    For the fitting I'm using Origin software.
    Dr Jeffrey J Weimer, I noticed a clear difference in parameters when I fitted my data to linearized and nonlinear equations. Nonlinear fitting showed good agreement with data. Linearized models showed low R^2 values for langmuir and freundlich models but for nonlinear analysis showed high R^2 values. it confused me

  • Is there any plant which do not have antioxidant activity?

    Today the terminology "Rich in antioxidants" has been easily equated in the public mind with "beneficial". Are all plants rich in such antioxidants or here also exception do exists? If exception exits what are the plants which do not have antioxidants.

    Thanking you.

    Chen Shanqiao · Shanghai Ocean University

    Since not all the plants have been assayed for antioxidant activities, it's difficult to say exception is not exist. However, all the plant are living towards oxidation stresses caused by oxygen in air, photosynthesis of them themselves, free radicals come from lipid autoxidation and so on. All of them have got antioxidant systems and substances due to evolution.

  • What is the impact of sustainable hospital design on patients's treatment processes?

    Hospitals, like all buildings, are both shaped by people and capable of shaping occupants’ behaviours and feelings (Gieryn, 2002). They are complex places that are simultaneously physical, social and symbolic environments (Gesler et al., 2004) The architecture of hospitals is, therefore, inextricably bound up with the forms of medical theorizing and medical practice which were operant at the hour of their construction and, what is more, all subsequent modifications to hospital design can be seen as a product of alterations in medical discourse,” Prior claims. 

    Hence somehow it has been believed that hospital designs effect to the patients's treatment processes. However which factors are having the best positive impacts on patients and how can we maximise their contributions?

    Thi Thanh Hai Truong · Deakin University

    Some info you may be interested 

  • Kittipong Tripetch added an answer in Antenna:
    Does an antenna with a range of 2m reach another antenna with 2m range from 3-4 meters away ?

    Say I have a blue tooth device that has a range of 2 meters and I try to connect to other Bluetooth device that has also range of 2meter.

    so while connecting does both the devices should be only 2 m away from each other or they can be 2-4 m away from each other.

    Logically I think only 2m.

    Kittipong Tripetch · Keio University

    Maybe you need additional power amplifier with optimal current drive and optimal supply voltage.

  • Hossein Kazerooni added an answer in Cerium:
    Can we obtain cerium oxide nanopaticle with the addition of hydrogen peroxide to cerium nitrate? is it essential to use a base like ammonia ?

    chemistry,chemical engineering,nanomaterial

    Hossein Kazerooni · University of Tehran

    sorry miss jamil

    but i dont want to use heat treatment like calcination in this case. you know that most of the researchers use ammonia to abtain cerium oxide. i want to know if i can use peroxide instead?

  • I'm looking for partners for the ERANETMED International project. Are you interested?

    Concerning the ERANETMED project (http://www.eranetmed.eu/​): I am looking for 3 partners from any of the following countries to participate as PIs working on groundwater hydrogeology and climate change:

    Italy - France - Germany - Greece - Portugal - Malta

    If you are interested, please send me an email with your CV or list of publications to start discussing the details.

    Best regards

    Dr. Ayman A. Ahmed

    Associate Professor of Hydrogeology

    Faculty of Science

    Sohag, Egypt

    email: ayman@sohag.edu.eg

    Jose joel Carrillo-Rivera · Universidad Nacional Autónoma de México

    I am also interested to colaborate in the project

  • Ferdinand Frauscher added an answer in Ultrasound:
    Does anyone use ultrasound to place epidurals in children in everyday practice?

    To see hôw feasible it is

    Ferdinand Frauscher · Medizinische Universität Innsbruck

    thats a good question

    we do it - the portable US systems are very good

    but I don't believe that all do this

    the older colleagues - who are not trained to US - I don't think they use US

    is the same with other infiltrations

    I prefer image guidance



  • Soran Kahani added an answer in Ionic Liquids:
    How can I identify morpholine acetate properties?

    Morpholine acetate is one of the ionic liquids I need to know about, but I couldn't find it. Is there anybody who can help me?

    Soran Kahani · Isfahan University of Technology

    Dear Fernando,

    Thanks a lot!

  • How to convert Chlorinity to Salinity?

    One paper mentioned Chlorinity of water sample = 300 mg/L. But another paper cited the first paper but interpreted as Salinity = 2‰.

    I found that the unit of Chlorinity is usually g/Kg, or written as ‰.

    I also found a relationship that: Salinity(‰) = 1.80655 x chlorinity


    I tried to convert Chlorinity (300 mg/L) to Salinity, but I did not get 2‰. So am I right or wrong?

    300 mg = 0.3g

    1L* 1.025 kg/L =1.025kg

    Chlorinity =  0.3 g/1.025 kg = 0.29‰

    Salinity = 0.29‰ * 1.80655= 0.5 ‰

    Henrik Rasmus Andersen · Technical University of Denmark

    I agree 300 mg/L chloride converts to approximately 0.5  ‰ if the main cation is sodium. If the water is something else than diluted seawater it can be different.

    Can you give the references to the two papers you mention.

  • Alaasaad abd el hamid asked a question in Paper:
    I need to open that paper how?

    I can not open that paper

  • Ahmad Abukashabeh asked a question in Isotope Analysis:
    How can one find an institute for doing summer fellowship(~2 months research) on ICP-MS and Isotope analysis?

    I have already done my M.Sc in chemical engineering and have a good experience on ICP-MS since 2008. I would like to join a research group for about 2 months then apply my knowledge on my instrument to do some kind of research collaboration and inter-laboratory comparison/research.

    Note: I am trained for advanced ICP-MS analysis by IAEA staff/Vienna

  • Kimmo Rouvari added an answer in Quantum Mechanics:
    Does “spin” imply physical rotation?

    The “spin” of an electron or other fundamental particle is often described as “intrinsic angular momentum”. This terminology is required because a point particle or Planck length vibrating string cannot possess ½ ħ of angular momentum. Larger objects such as molecules or electrons in atomic orbitals possess quantized angular momentum which can be demonstrated to involve physical rotation. For example, a carbon monoxide molecule in a vacuum can only rotate at integer multiples of 115 GHz which is integer multiples of ½ ħ. Therefore, do you believe that fundamental particles have a physical angular momentum that is currently not understood? Alternatively, is "intrinsic angular momentum" an accurate description of spin because it is a quantum mechanical property that does not involve physical rotation?

    Kimmo Rouvari · N/A


    Selection event caused by e.g. magnetic field. Spinning vector hence spin exists all the time. By measuring it we quantize it.

    TOEBI isn't ready yet, hence not include everything. Maybe I should call it Theory of Some Things by Illusion...

  • Nisha Rani asked a question in Massive MIMO:
    Wheather the EM wave hazards be reduced in massive mimo because of using low power antennas?

    In massive mimo large number of low power antennas are used at the base station. Because of this low power transmission, do the hazards get reduced or not?

  • Ahmad Bahmani asked a question in Materials Studio:
    How can I find out the atomic position of a crystal with known space group(using http://www.cryst.ehu.es/ website)?

    In the following link, the atomic position of different space groups has been shown.



    For a first principle calculation, I need to know the atomic position of a compound. I found the crystal space group (e.g. Immm (Pearson number:71)). But for adding atoms in materials studio, I don't know how I should find the atomic position.

    I really appreciate if you help me to find out how to use this website. what should be replaced by x, y, z?

    Best wishes,

  • Can somebody tell me something about organo phosphate microbial degradation ?

    Microbial degradation of pesticides

  • Marcel M. Lambrechts added an answer in Reality:
    Do great scientists communicate with the real world successfully?

    Many scientists are truly occupied with their researches, experiments and studies. Considering often remarkable ideas in depth, some of them have built their own realities. Hence, are they capable of communicating with society successfully?   

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    Do you know the inventors of the tools you use at home?