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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

    Thank you, Guido, for the references.

    I believe the problem of PE and DVT is more serious when doing vertebroplasty. In the case of kyphoplasty these complications are rarer because of the preliminary preparation of room for the cement and the lower intravertebral pressure.  

  • Omid Zabeti asked a question in Topological Groups:
    Can an abelian topological group conatain a projection homomorphism?

    Let G be an abelian topological group. For a fixed element g in G, can we find a projection which is homomorphism, too. I mean a homomorphism like P that P^2=P?

    We can add additional hypothesis to G, like locally compact or connected.

  • Alokmay Datta added an answer in FTIR Analysis:
    Which type of functional group will appear in FTIR analysis as peaks after covalent conjugation of enzyme?

    The ―COOH of nanoparticles was activated using EDC/NHS and then covalently attached to the ―NH2 of the enzyme, forming ―CO―NH―. Now, which peaks number will show that the conjugation successfully done? 

    Alokmay Datta · Saha Institute of Nuclear Physics

    The C-N-O symmetric stretch should appear at 1358 cm^-1.

  • Veli Himanen added an answer in Civil Society:
    Are there any comparative studies about civil society in the Latin American new left and the former socialist East European countries?

    Especially the Ecuadorian case, and the Czechoslovak experience.

    Veli Himanen · Relate Partnership

    I have made one comparitive stuy (attached below) including also these two countries you mentioned. If you need, you can also download related data from RG.

  • Does Q.M. need refinement?

    A system of ideal gas can always be made to obey classical statistical mechanics by varying the temperature and the density. Now a wave packet for each particle is known to expand with time. Therefore after sufficient time has elapsed the gas would become an assembly of interacting wavelets and hence its properties would change since now it would require a quantum mechanical rather than classical description. The fact that a transition in properties is taking place without outside interference may point to some flaw in quantum mechanics. Any comments on how to explain this.

    Jacques Moret-Bailly · University of Burgundy

    Solutions of linear equations (Schrödonger for instance) do not have singular points which could be centers of particles. Thus

    - as using Schwarzschild-Fokker trick, electromagnetism is linear, photon cannot exist.

    - as Louis de Broglie, Schrödinger,...think, equations of particle fields cannot be linear. They must be solitons...that our mathematics are unable to study.

    Wave-particle duality is not a problem of physics, it is a problem of mathematics.

  • How can I use R software to perform the Mann-Kendall Test for trend analysis and abrupt change

    I want to use daily precipitation data to analysis the trend of rainfall.Thanks.

    Raoof Mostafazadeh · Tarbiat Modares University

    Also attached available document on the web may helps

  • How can I determine the switching time of 2-level voltage source inverter using 'Space Vector Pulse Width Modultion' ?

    There are six sectors in SVPWM. For each sector, switching time are different. During the switching time calculation, switching frequency should be equal to the frequency of each sector. How to give the switching time to pulse generators for the simulation of 2-level voltage source inverter.

    Martin Schulz · Infineon Technologies

    Dear Anup,
    I think there might be a misunderstanding in technical terms.

    As the abbreviation SVPWM sais, there only is a change in pulse width Ton, the switching frequency fs=1/(Ton+Toff) will remain constant at any time.

    As a consequence, there is no such thing as a change in frequency in any sector.
    Calculating the ratio Ton/(Ton+Toff) is well described in a lot of literatures.

  • How could translation contribute to second language acquisition?

    Translation is usually treated separately from SLA, while it has a significant role in developing learners' competence. 

    Vladimir Farber · Ben-Gurion University of the Negev

    If you translate with such program as google translate and after that you push the button "Listen" and listen what it says this can improve your reading skills. If you also will try to remember new words used in the translation process, this can improve your vocabulary.

  • Shakir K asked a question in Customer Satisfaction:
    Service Quality vs Customer Satisfaction?

    How does the customer satisfaction relate to service quality in education sector.

  • Is Normality of data necessary for regression analysis?

    I am wondering is it really necessary to have normally distributed data for Enter or stepwise regression? Also if its not normally distributed than do we have to transform it before running regression? 

    Kalsoom Jaffar · Glasgow Caledonian University

    Also is there any way to check time lag effect of economic data? such as inflation and interest rates?

  • Martin Spinrath added an answer in Field Theory:
    Why do we have input antiparticle effect when T is not equal to 0?

    In relativistic mean field theory,i found antiparticle effect have to be calculated in lagrangian formalism for T is not equal to 0, i need explanation about contribution of fermi energy too. Thank you

    Martin Spinrath · Karlsruhe Institute of Technology

    Dear Yuri,

    Thanks for the references but I have the feeling they go very far away from the original question. So let us wait for a reply from Ibu Fitri.

  • Ljubomir Jacić added an answer in Development:
    Are information technologies a key catalyst to success and development of non-developed countries?
    We are more than ever trying to convince the young that professions dealing with IT technologies are not just for genius people, but for everyone. Right after they graduate, there is a prospect of finding jobs with monthly wages well over the average in Serbia. All they need is to be hardworking and ready to learn and move forward. IT technologies are a great way for the developing countries to advance, promote and use for the benefit of everyone. All that is needed for taking "IT steps" is: a few computers, a little space and a lot of "brain" space. What are your experiences of this?
    Ljubomir Jacić · Technical College Požarevac

    We have a Journal Information Technologies and International Development with some papers that cover the issue of this thread!

    Happy New Year my dear RG friends!

  • Shiv Yadav added an answer in Seedling:
    Which is better for estimating vigour- Seed Vigour Index I or II?

    I am looking for an explanation regarding VI-I with respect to seedling elongation and VI-II with respect to dry matter accumulation; physiological reasons and advantages in different situations, if any.

    Shiv Yadav · Indian Agricultural Research Institute

    Thanks Dr. Khaled for your kind input.

  • What will be easy technique to detect phosphorylation and pyrophosphorylation in protein?

    I am looking for detection of phosphorylation and pyrophosphorylation on protein. Please suggest me simpler technique other than Mass spectrometry, western blotting and autoradiography.

  • Can anyone tell me where I can download CST Microwave studio for windows?

    Hello. Can anyone tell me where I can download CST Microwave studio for windows?

    I can't find any torrent link 

    Karim Loukil · CERT

    To Zelimkhan Khakiev: Could you kindly provide me also with the CST studio suite 2014 or older version  torrent link as well pls?

  • Martin Schulz added an answer in Transformers:
    What are the effects of a transformer's core saturation?

    What operational characteristics it will show?

    Martin Schulz · Infineon Technologies

    Dear Salah,
    assuming you're operating a typical transformer to convert a sinusoidal input voltage into a sinusoidal output voltage, saturation of the core will have two most prominent effects:

    1) as described by Bhupendra, the linearity of the transformer is disturbed, leading to clipping - flat tops at the output voltage tips - which will induce unwanted harmonic distortion to the output.

    2) the loss-situation for the transformer changes leading to increased temperatures in the core which, at some point, may lead to damage to the transformer

    Assuming you consider a ferroresonant transformer, saturation of the core is a method of magnetically stabilizing the output voltage.
    If done properly, the input voltage may vary by +/-50% while the output voltage only changes by +/-5%. This ferroresonant approach was widely used prior to having proper power elctronics at hand. Efficiency is pretty low at <80% but it works very well in weak grids without the nedd of microcontrollers.

  • Joan Rosen Bloch added an answer in Gold:
    Does anyone know the research gold standard of measuring telemere length to capture a biological measure of weathering in mothers?

    This is important to move forward health and social equity research.

    Joan Rosen Bloch · Drexel University


     Thank you. These articles are very helpful.

    I use  'weathering' as a construct coined by Arline Geronimus that stems from her work studying racial/ ethnic perinatal health disparities in preterm birth rates among African American women.

    Best regards,


  • Veli Himanen added an answer in Energy Resources:
    Can science provide solutions for the main problems of the world?

    Nowadays, there are some high priority problems at a global level, such as: poverty, limited energy resources, limited food and even drinking water (especially related to the population growth phenomenon), global warming and rapid climate changes, the gap between developed and undeveloped countries. 

    Veli Himanen · Relate Partnership

    The question posed is immensely broad. I recently wrote a book (attached below) in the related subject. In the following, I would like to point out some major issues in order to structure the question. First, science is mainly providing knowledge and when our actions are for an important part based on knowledge, we may consider that science provide an important base for solving global problems. Second, global problems form, of course, a complex system. I have divided them to three sub-groups: traditional, modern, and post-modern. Every sub-group can be attacked with somewhat different actions. Third, technology and science differ from each other. When science is after knowledge, technology is a means to fulfill a human purpose. Actually, technology is much older than science but during the last 200 years, technology has gained much from scientific knowledge. Fourth, our earth is currently divided into 200 countries. Everyone’s destiny is very much affected by the country she happened to be born in. Fifth, according to North et al (2009) world countries can be divided according to their social orders into three groups: limited access orders, transition, and open access orders countries. It is obvious that scientific knowledge is easier to accept in the last ones. However, many human and political interests will influence the possible actions.

  • Are there some reliable natuaral sciences simulation tools available ?

    Several times we need to simulate the physical situations on PC which may be in any field like electromagnetics, mechanics, particle physics, cosmology, geography, solid state, quantum mechanics, reactor physics etcetera.

    Is there any unified tool available for simulating the events? 

  • Stefano Campanaro added an answer in NCBI:
    Where can I get the reference sequence for 16S rDNA?

    I have analyzed gut flora of Helicoverpa and found B. pumilius, with some strain identification by 16S rDNA analysis.

    I want to check these strains via nucleotide diversity by DNA sp software. I am looking reference sequences of 16S rDNA of those strains. Can you please suggest other than NCBI data base for getting reference sequences for diversity analysis of these strains?

    Stefano Campanaro · University of Padova

    Be careful using 16S rRNA to check strains and species, frequently strictly related species has nearly identical 16S sequences. You can check greengenes database or RDP and verify if 16S sequences of the strains you are interested are available.

  • Can anyone help me with the problem in Protein expression and lysis buffer?

    I am expressing 6xHis tagged 8.5KDa human Protein (pI~4.19) which cloned into pET21b expression vector and express in BL21 DE3 Codon plus strain. I see expression when I mix bacterial pellet with SDS Gel loading dye(Gel loading buffer contains 0.05% bromophenol blue , 40% sucrose, 0.1M EDTA (pH 8.0) and 0.5% SDS) and heat at 95°C for 5 miutes and then load on 15%SDS PAGE. But when I lysed it with lysis buffer (500mM NaCl, 20mM Tris pH 8.0, 2mM Benzamidine and 10 µg/ml Soyabean Trypsin inhibitor) and then sonicate it with pulse 2 Second ON and 12 second OFF For 6 Minutes with 32% amplitude, I am not able to see expression in supernatant as well as in pellet.
    I also purified it with Ni-NTA beads and elute with 150, 250, 350 and 450 mM Imidazole but nothing was detectable on gel.
    I also monitored OD of Induced and Uninduced culture for see whether my protein is toxic to cell or not and Uninduced culture grow at double rate compare to Induced culture.
    Please suggest me-
    1. Is my protein toxic to bacterial cell?
    2. Is there any relation with pI of protein and pH of lysis buffer? As my protein pI is 4.19 and I am using lysis buffer with pH 8. If yes then what will be suitable pH for lysis buffer and its composition?
    3. Whether my protein is express or not?

    All gel picture and OD data is attached with word file.

    Mohd ZIAUDDIN Ansari · Indian Institute of Technology Guwahati

    @Adam B Shapiro thank you sir for giving me a valuable suggestion

  • Robert A. Shanks added an answer in Bubble:
    How can I cure Styrene-acrylonitrile (SAN)?


    I need some information about working with Styrene-acrylonitrile (SAN) as a nano-film? First, how do you know its cured? The solvents I've been trying has a very high BP, above 150 degrees. Heating it on a hotplate (60 deg) only causes bubbles in the film. Instead I am curing it in room temperature. I have experience with PDMS which using curing agent. How does it work with SAN?

    I use solvents to dissolve the powder of Styrene-acrylonitrile and then deposit it. Some solvents I have tried, example 1,2-Dichlorobenzene, doesn't work very well. I don't get a very uniform thin film, instead when its deposited and "cured" it becomes grainy. I also only need a very small amount of SAN, a few milliliters.

    Thanks in advance, 

    Robert A. Shanks · RMIT University

    Poly(styrene-co-acrylonitrile) (SAN) is a thermoplastic, which means that is does not cure (crosslink). The examples given by Karim Osouli are where the epoxy resin cures while the SAN is dispersed in the epoxy matrix.

    Cast a film from a solution of SAN and leave it until the solvent has evaporated, finally removing the last trace of solvent under vacuum. The SAN solution in liquid solvent will undergo a phase transition to a solid solution of solvent in SAN (that is reversed from liquid to solid). If a precipitate of SAN occurs during evaporation then particles or surface defects will form instead of a uniform film. Finally equilibrate the film by heating above glass transition temperature (Tg = 105-110 °C) while clamped flat or in a heated press, which should remove any stresses formed during solvent evaporation.

  • Fateme Jafarzade asked a question in Shell:
    How can i resolve convergence problems of thin wall shell element ?

    i am modeling a thin wall shell element column under temprature and i have 2step<first is heat and second step  is displacement control method 0.3mm/min:during of submit i have this error "too many attempted made for this incrument"in second step, first incrument :::because unstable system                          now i dont cant resolve convergence problems this unstable system... do yow know?

  • Kamal Akl added an answer in Pediatrics:
    What are the most common types of unstable conditions or emergencies in the pediatric population?

    I am preparing a thesis and I hope to extend our current Rapid Response Team to incorporate the pediatric population for effective emergency care. What type of unstable conditions or emergencies do you see in the pediatric population?

    Kamal Akl · University of Jordan

    As mentioned by Jean Kiko diarrhea with dehydration is an important cause of mortality and morbidity. Rota virus may cause severe recurrent watery  diarrea leading to prerenal AKI, which if not recognized early,  may progress to stage V prerenal azotemia( with hemodynamic instability) and intrinsic AKI.

    AS for Karmen: HUS is not that common. We see only 1-2 cases per year

  • Amino Acid Congress - august 2015 in Vienna?

    This is to invite you to the 14th International Congress on Amino Acids, Peptides and Proteins August 3-7, 2015, Vienna, Austria.
    The forum will provide an invaluable opportunity for scientists and students to learn from exciting research conducted outside of their own laboratories, to develop new research collaborations and to freely exchange scientific ideas in a friendly setting.

  • Jörg Maria Ortwein asked a question in Volition:
    Volition in music - Seeking for internationale colleagues for further development of a volitional online test - interested?

    The "will test in music" is available as volitional test for German speaking music students. This test should be provided in different language versions. In a first step, I would like to make an introductory paper available that has been published as German-language article in the Journal "Üben & Musizieren" in 2013. The next steps are to develop different language versions of the test. I'm seeking for international colleagues who want to help me with these steps.

  • What are the current most efficient approaches to produce salt tolerant crop cultivars?

    I'm searching for recent approaches of producing salt tolerant crop cultivars.

    Arun Lahiri Majumder · Bose Institute

    we have been able to produce salt-tolerant rice plants by introgression of a salt-tolerant inositol synthase gene (PcIno1)  from the wild rice, Porteresia coarcta.

  • Martin Schulz added an answer in PDB:
    Have reviewers ever asked you to provide a pdb?

    This is the first time a journal has contacted me to tell me that one of the reviewers wants me to provide them with the pdb's for a paper. I have never been asked to send a pdb to a reviewer before ... pdb codes after deposition in the PDB, tables with structural statistics and pictures to illustrate the findings seemed to be all I needed to provide until now.

    Is this common practice?

    Martin Schulz · Infineon Technologies

    Dear Antonio,
    me too, I have no idea what "pdb" means.

    But I do a lot of reviews and I would never ask an author to provide any sort of raw data exceeding what is written in the paper.
    If there were technical details that needed clarification, this could most likely be done in communication done by mail.

    If your miraculous pdb-file contains any data relevant for intellectual property (IP), I'd strongly advise not to share it and try to solve any issue by sticking to the paper's content.

  • Are the basic reproduction numbers of at least one strain of all infectious microorganisms available?

    I can easily find the basic reproduction number of deadly, or serious infectious microbes such as HIV, Ebola, rubella, TB, and MRSA. However, it is more difficult to find it for other microbes. So, is the basic reproduction number of at least one strain of all infectious microorganisms available? if yes, what is the most reliable reference collecting them; if no, what is the criteria upon which we decide we should estimate the basic reproduction number. Also, for known basic reproduction number of different strains of a single species, are they significantly different (for instance, MRSA , VRSA, and other sensitive staph. aureus do they have a different R0). Thank you

    Omar Elkadi · Cairo University

    Actually, I need a reliable reference that I can releate to when needed, also if you have any info. About the 

  • Szymon Strnad added an answer in Ammonium Sulfate:
    Why Saccharomyces cerevisiae colony changes color from white to light yellow when plated on synthetic media and incubated for 4-5 days?

    Dear all, when I plate Saccharomyces cerevisiae ( BY4741) on SD media ( YNB+Ammonium sulfate+glucose +amino acids), initially it grows as white colonies and when incubated longer (4-5 days) colony color changes to creamish to yellowish in color. I am just curious to know why there is change in color from white to yellowish?

    Szymon Strnad · University of Agriculture in Krakow

    Similar thing used to happen with Candida sp., Trichosporon sp. or Hansenula sp. cells. My master's thesis advisor at that time explained to me it has to do with the process of ageing. I was curious too.