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  • Yaser Gohari asked a question in Magnetics:
    How is magnetic leakage reduced to a minimum in commerical transformers ?

    hi, How is magnetic leakage reduced to a minimum in commerical transformers ?

  • Gino Marioni asked a question in Authorship:
    What about the importance of a significant proportion of leading authorship positions in IF papers to evaluate clinical research professionals career?

    professionals of clinical research

  • Stam Nicolis added an answer in Fundamental Physics:
    Is the remark of Richard Feynman (I think I can safely say that nobody understands quantum mechanics) still valid or acceptable?

    Regarding our current understanding of quantum mechanics, especially the interpretation of the theory of measurements in terms of parallel universes.

    Theoretical physics, quantum mechanics, Fundamental physics 

    Stam Nicolis · University of Tours

    Fields on the lattice take values in the Lie group (distinct from the Lie algebra). For compact Lie groups (as is the case for the Standard Model, for instance), the corresponding manifolds are compact spaces, of finite volume. Therefore, when computing any correlation function, if a gauge condition isn't imposed, the redundancy in the calculation will give rise to a finite factor in numerator and denominator, equal to the volume of the group manifold, raised to a power equal to the volume of the lattice. 

    In the continuum, the corresponding calculation involves fields taking values in the Lie algebra, which is a manifold that has infinite volume. Therefore, even for a finite spacetime volume, the redundancy factor is infinite and correlation functions are ambiguous expressions oo/oo. A gauge fixing condition renders the calculation finite and the existence of gauge invariant observables expresses the fact that there exist quantities that don't depend on how the gauge fixing condition is realized. 

    For noncompact gauge groups, however, the group manifold still has infinite volume and, therefore, a gauge fixing condition is, needed for the same reason. That's one challenge in studying gravity on the lattice. 

    However for compact groups, like SU(3)_color, even though the lattice regularization breaks Lorentz invariance, this symmetry is a global symmetry  and doesn't require additional tuning conditions to be recovered in the scaling limit. Therefore there's no problem of principle in computing the gauge invariant functions of the Wilson loops that contribute to the potential between nucleons, for instance. It's a difficult calculation, but the resources linked to in previous messages show how the calculation is set up and carried out. 

  • Abdur Mirajkar added an answer in HPLC Analysis:
    I have a chromatogram of my sample and I have standards. Now what?

    Hello everybody!

    I am initiating my research on HPLC. I have used a C18 Accucore column, A gradient program of 40 min (60min in total) using as eluents MeOH (A) and Water(B), both acidified with formic acid 0,1%.

    My samples have 0,5mg/ml of concentration. My standards(11) concentration are 1mg/ml...of course the peaks i see in my samples are quite smaller. I injected a sample with the mixture of all standards in order to identify them in the run.

    Ladies and gentlements...what is now the best procedure to analyse and identify (if possible) some of the peaks?!

    All were injected in 3x, but it seems to me that are some deviations of peaks in some situations....not very happy with this?

    Can anybody suggest me a way of solving my problem? Also, is there a free software to treat chromatograms (actual software is chromeQuest) and possible do statistical treatment?

    Thank you very much

    Abdur Mirajkar · Pivotal Therapeutics Inc.

    Hello Joana,

    You first  need to run your standards to figure out number of components and retention time including relative retention time of each peak.Once you have run your standard you can run your sample to match RTs and RRts. Once this matching is   done you can spike your sample with standards to check the overlapping and recovery.

    If you are only using HPLC you sholuld be able to compare retention time of standards with your sample if they are same the compounds or else you have to use LC-MS to identify the components of your interest.

  • Ilya Tsyrlov asked a question in Ketoconazole:
    Is 6 to 30-fold variability in activity of hepatic CYP3A4 in drug addicts infected with HIV due to genetic, social, medical or environmental factors?

    All the above factors might be involved, although the prevailing factor is drug-drug interactions, namely methadone vs NNRTIs, PI vs NNRTIs, epistatins vs NNRTIs, antifungal ketoconazole vs NNRTIs, taxol vs NNRTIs, etc.

  • Francisco Falcone added an answer in 4G:
    Could anyone tell me about any equivalent to the planning task in the 3G or 4G generation?

    In other words, is the problem can be formulated as in 2G or has other formulations. Any references would be reallyy valuable. Thank you in advance

    Francisco Falcone · Universidad Pública de Navarra

    As stated previously by Tarik, network/cell parameters are more complex (at least in 3G; 4G is a whole new case, as functionalities such as SON can decrease optimization and planning tasks to some extent). As a really basic comment, I would say:

    2G: you provide frequency plans for BCCH and TCH channels. You also work on intra-RAT HO.

    3G: you provide Scrambling Code planning, CPICH power planning distrbution. In terms of HO, you now work with SHO, as well as with Inter-RAT HO.

    This is really very simple and only on the radio side. Hope it can help. Good luck!

    All the best,


  • Homayoon Ranjbar asked a question in Ground Truth:
    What is the best procedure to compare/show similarity between images reconstructed from PET data by MLEM ?

    I have a ground truth image of an object that is recovered from Positron Emission Tomography data by Maximum Likelihood Expectation Maximization. I have other three images of the same object, but from a different data set and also by MLEM. 
    I want to compare these three images with each other in terms of closeness to the ground truth image. 
    One can tell the similarity by observation, however I need a more rigorous way to quantitatively show that one of these three look more like the ground truth image.


  • Yun Lu added an answer in Protein Detection:
    Are the endogenous levels of p21 and p27 protein detectable in H82 or other small lung cancer cells?

    I treated H82 small lung cancer cells to induce cell death, and our real-time PCR data suggest that p21 and p27 mRNA levels are increased (CT scores are around 27). then, I try to detect protein levels using santa cruz antibodies against p21 and p27. However, i can not detect these two proteins in either control or drug-treated cells. I am wondering whether anyone has experience with the detection of these two proteins in H82 or other small lung cancer cells?

    Yun Lu · Geisel School of Medicine at Dartmouth

    I agree that cell signaling antibody is better then santacruz one. The antibodies I used now can detect overexpressed p21 and p27. Hence, i am wondering whether the endogenous levels of P21 and p27 are too low to be detected. However, the rt-PCR shows the mRNA levels of p21/27 may be high in cells since the ct values is 26-27.  what confuses me is why the protein levels are undetectable if the mRNA ct is high enough. 

  • Lars Öhrström asked a question in Ligand:
    When analysing the topology of a MOF built from polytopic ligands do you think it appropriate to represent this ligand by two or more nodes?

    For example: a 4-c ligand could be represented by two 3-c nodes if this describes the structure better.

  • Saeed Moradnoory added an answer in Trigonometry:
    I think Fermat's last theorem can be proved trigonometrically as in my article, mathematicians will you please read & comment my article ?

    Please find my attached article below, considering Fermat's last theorem according to trigonometry & polar coordinates. I appreciate your comments. Thank you.

    Saeed Moradnoory · Khorasan Institute of Higher Education

    Was excellent though my specialty, but I liked about it Dygs

  • How can I measure the transmission coefficient of a EBG using the transmission line model?

    I'm currently working on an electromagnetic gap band EBG and need to measure the bandwidth filtered by an EBG and this by using the transmission line model and measuring the transmission coefficient using CST microwave studio, , need an example ,please !

    Francisco Falcone · Universidad Pública de Navarra

    Hello, probably the closest thing you will find is the extraction of ABCD matrix values from S parameters for a unit cell of your EBG structure (I am thinking of a waveguide approach to the EBG, such as a microstrip line). From there you can cascade elements and obtain a model, which can be analyzed in terms of coupled mode theory. Please check the work by Prof. Lopetegui and Prof. Gomez-Laso on the topic, they have provided thorough description of this case. Hope this can help!

    All the best,


  • Are there simple proofs of Fermat's last theorem?
    Beside rigorous proofs of Fermat's last theorem, there are relatively simple approaches to arrive at the same conclusion. One of the simple proofs is by Pogorsky, available at http://vixra.org/abs/1209.0099. There is also a website called www.fermatproof.com which gives an alternative proof, and also a review paper by P. Schrorer at : http://www.occampress.com/fermat.pdf. Another numerical experiment was performed by me around eight years ago (2006), which showed that if we define k=(a^n+b^n)/c^n, where a,b,c are triplets corresponding to Pythagorean triangle (like 3,4,5 or 6,8,10), then k=1 if only if n=2. It seems that we can generalize the Fermat's last theorem not only for n>2 but also for n<2. But of course my numerical experiment is not intended to be a rigorous proof. Our paper is available at http://vixra.org/pdf/1404.0402v1.pdf, based on 2006 version article. So, do you know other simple proofs of Fermat's last theorem? Your comments are welcome.
    Sinan Ibaguner · Yeditepe University

    Please visit my page & see my article related to Fermat's in relation to trigonometry & polar coordinate form.

  • Why are only dopaminergic neurons of SNpc susceptible to MPTP-induced neurotoxicity?

    How MPTP can precisely effect only dopaminergic (DA) neurons in substantia nigra while creating mice model of Parkinson's disease, and not DA neurons in other areas of the brain ?

    Vidyadhara D J · National Institute of Mental Health and Neuro Sciences


  • Saeed Moradnoory added an answer in Moscow:
    Who cited ecology publications of Moscow University?

    Analysis of citation is useful

    Saeed Moradnoory · Khorasan Institute of Higher Education

    آیا منظور شما این است: ما در عصر بوم‌شناسی پسرو به عنوان یک شهروند موظفم اطلاعاتی درباره این موضوع داشته باشیم. در سی سال اخیر تحول بزرگی در نحوه نگرش ما نسبت به رابطه انسان با زیست‌بوم خود پدید آمده است که نتیجه آن شدت بخشیدن به مطالعات علمی در زمینه محیط‌زیست و جنبش‌های زیست‌محیطی بوده ‌است. به همان اندازه که دانستن فیزیک برای یک مهندس ضروری است، داشتن اطلاعات از بوم‌شناسی برای کسی که می‌خواهد مشکلات پیش روی بشر، در راه حفاظت از محیط زیست را بررسی کند، الزامی است. در کتاب «بوم‌شناسی؛ مطالعه‌ی تجربی توزیع و فراوانی» نوشته چارلز جی. کربز که به عنوان منبع درسی دانشجویان در دنیا و پرفروش‌ترین کتاب بوم‌شناسی شناخته‌شده است، نویسنده بوم‌شناسی را مجموعه‌ای از مسائلی که دانشجو باید به شیوه‌ای انتقادی با آنها برخورد کند معرفی نموده است و با تأکید بر نقش آزمایش در سنجش اعتبار نظریه‌های اکولوژیکی، بسیاری از مسائل توزیع و فراوانی را که امروزه محل مناقشه است به بحث گذاشته است. نویسنده در هر فصل کتاب سئوالی را درباره مکانیزم عمل جمعیت‏ها و اجتماعات در طبیعت مطرح کرده و سپس اطلاعات کافی برای آنکه خواننده خود به فکر واداشته شده و نتیجه‌گیری نمایند در اختیار آنان قرار می‌دهد. در انتهای هر بخش همچنین سئوالاتی را که برخی هنوز بی‌پاسخ مانده‌اند، آورده است، سئوالاتی که می‌تواند به عنوان موضوع بحث در کلاس درس مطرح شوند. به اعتقاد کربز پی‌آمدهای عملی تفکر اکولوژیکی باید سئوال اساسی محققین این رشته باشد. در ویرایش جدید فصل‌هایی نیز به پویایی جمعیت‏ها، زندگی انگلی و فشارهای بشر بر سلامتی اکوسیستم اختصاص یافته است. نویسنده در هر فصل به ذکر سابقه تاریخی تحقیقات اکولوژیکی به همراه عکس‏هایی از اکولوژیست‏های مشهور پرداخته است، به اعتقاد وی علم به طور کلی یک فعالیت انسانی است و دانشمندانی که به مسائل اکولوژیکی پرداخته‌اند به ویژه شخصیت‏های جالب ‌توجه و شایسته شناخت بیشتر هستند. کربز بسیاری از فصل‏های کتاب، به ویژه فصول مربوط به زیست‌شناسی بقا، سازمان اجتماعی و محصول اولیه، تقویت همبستگی تکاملی و بوم‌شناسی کارکردی را مورد بازنگری و تجدیدنظر قرار داده است. زیست‌شناسی بقا، تمرکز بر مسائل عملی‌ای است که نیازمند توضیحی بوم‌شناختی بوده و عمده رشد دانش بوم‌شناسی از همین زاویه صورت می‌گیرد. نویسنده به اکولوژیست‎ها توصیه می‌کند یک گام به عقب رفته و از منظری انقلابی! به سیستم‎های اکولوژیکی نگاه کنند و معتقد است دانشجویان تکامل نیز تنها با دانستن چگونگی عملکرد سیستم‎های اکولوژیکی قادر به درک صحیح انتخاب طبیعی خواهند بود. کربز در مقدمه خود بر ویرایش جدید کتاب می‏گوید: "اگر پیامی در این کتاب نهفته باشد یک پیام ساده است و آن اینکه پیشرفت در حل مسائل بوم‎شناختی هنگامی پیش می‏آید که از روش‏های تجربی استفاده شود. عادت به طرح این پرسش که با "کدام آزمایش می‏توان به این پرسش جواب داد؟" در حکم اساسی‏ترین وجه روش علمی است که دانشجویان بایستی آن را در خود بپرورند. هرجا که در مورد یک مساله بحث و جدل باشد طرح این پرسش ما را به کانون آن مسئله خواهد برد." دیباچه کتاب بوم شناسی
    We live in the age of ecology and duty as a citizen to have information about it. In recent years a great change in our attitude towards the relationship between man and his environment has emerged as a result of the intensifying scientific studies on the environmental and ecological movements. As the knowledge of physics for the engineers is essential for someone who wants to have information on ecological problems facing mankind in the environmental review is mandatory.
    In the book "Ecology, Experimental study of the distribution and abundance" by Charles Jay.distribution and abundance is now in dispute is discussed.
    At the end of each of the questions that still remain unanswered, some, have, questions can be raised as a topic of discussion in the classroom. Krbz practical consequences of ecological thinking researchers believe to be the fundamental question this.
    The new version also has chapters on population dynamics, living parasites and human impacts on the health of ecosystems is dedicated.Knowing more.
    Krbz many chapters, especially chapters on conservation biology, the social organization and the primary products, strengthening the relationship between evolutionary and functional ecology is reviewed and revised.
    Conservation biology, focusing on issues that require clarification ecological operation and growth of knowledge-based ecology from the same angle. Ecologist and author recommends a step back and view the revolutionary! Look at the evolution of ecological systems and believes that students only know how ecological systems will be able to understand natural selection.
    it will take the issue to the center. "

  • Xilin Zhang asked a question in Affect:
    Is there any evidence of the lower BOLD signal for depression compared to normal people?

    Is there any evidence of the lower BOLD signal (or the whole brain signal) for depression compared to normal people?

    or is there any evidence of the lower brain signal for negative affect compared to positive affect? 

  • Jaime González-Gómez added an answer in Jaw:
    What diseases can cause such changes in the mandible?

    Dear friends! The jaw belongs to a teenager of 15 years, 15 thousand years Paleolithic. What diseases can cause such changes in the mandible (besides scurvy)? 

    Jaime González-Gómez · University of Veracruz

    I think it down to lack of vitamin D. A probable lack of exposure to sunlight, which I guess was common 15.000 years ago.


  • Beghdaoui Djamila asked a question in Silvaco:
    How can plotting the bandgap energy versus temperature and X composition for an ternarery material using silvaco atlas?

    Im looking to plot the bandgap energy versus temperature and composition by Silvaco atlas

  • Ganesan Karuppiah added an answer in MFM:
    Can anyone say about the information depth in MFM ?

    In case of ion beam sputtered thin cobalt film of thickness 450 nm i want to measure the amount of magnetisation. From which distance below the MFM information will give the idea.?

    Ganesan Karuppiah · Indira Gandhi Centre for Atomic Research

    The information depth is very large in MFM ...much larger than your film thickness. Also it can be sensitive for a field as small as 10^-10 emu. (depending upon the tip)

    Also, MFM measures the magnetic force between sample and tip but not the magnetization. Of course, one can convert the magnetic force into magnetization after tip calibration but it is not trivial.

  • Chronic stress leads to anxiety or depression?

    Chronic stress can lead to anxiety in some people, while it can lead to depression in others. Some people with chronic stress may experience both anxiety and depression. It seems not clear how stress, anxiety, and depression contribute to each other. How can we interpret these different combinations of co-morbidity?

    Onitra Wilkerson-Proffer · Ashford University


    To answer your question in an undergraduate manner, when an individual is under constant stress, it can, indeed, lead to anxiety and depression. According to Harding (2014), when a person's body is exposed to the stress hormone, cortisol, on a constant basis, not only can it affect the body, it can also affect one's mental health.

    Further, according to Maculaitis (2013), too much stress can cause a plethora of health concerns, including mental health concerns, including panic disorders, anxiety, and depression.

    Harding, A. (2014, April). Stress effects: Understanding your body's reaction to tension. Student Health 101, 9(8), 17-18. Retrieved April 23, 2015, from http://readsh101.com/ashfordu.html?id=e88bbc2a&page=17 

    Maculaitis, L.. (2013, December). Stress: Head to toe, how stress affects your body. Student Health 101, 9(4), 7-8. Retrieved April 25, 2015, from http://readsh101.com/L/ashfordu.html?id=33cedaa9&page=7

  • How can I develope the parameters for a parabolic trough collector receiver as described below?

    b) Developing an appropriate charging/discharging control strategy/system for Receiver in a solar field.

    c) Re-engineering the collector cell to achieve better heat transfer with the circulating HTF or developing heat transfer enhancement mechanisms in the receiver in order to achieve this.

    Taqiy Eddine Boukelia · University of Constantine 1

    Its a deep and complicated question;

    1. For the first part of the question, I think it involves finding the optimum charging time of the fluid in the solar field in the day time and discharge it in the non-solar time (night), to reduce the heat losses in the solar field and to decrease the energy required for freeze protection temperature of the working fluid especially if you use the kind of fluids with high temperature range such as solar molten salt.

    2. For the second part of your question, as I think its based on two main points:

    A. Optimize the dimension of your receiver or using baffles inside the receiver to enhance the convective heat transfer between the inner wall of the receiver and the fluid.

    B. Or using different kind of fluids with high a heat transfer coefficient such as oils, salts or even nano-fluids.

  • Numan Khan asked a question in ANSYS Autodyn:
    How to find parameters for equation of state (Shock) for 4340 steel in Ansys autodyn?

    I am simulating the bullet impact in Ansys  15.07 Autodyn. I am using Jhonson-cook model with Mie-Gruneisen equation of state for 4340 steel plate of thickness 2 mm. I am unable to find the constants used in Autodyn for the Mie-Gruneisen equation of state for steel. Any one please share the following  values.

    C1, S1, S2, C2, Relative volume VE/V0, Relative volume VB/V0 etc

  • Ron Reiserer added an answer in Spin Coating:
    How to dry the chip after development of PMMA and LOR?

    I have problem when I dry it with spin-coater. It is not possible to keep 500nm-wide PMMA stuck on top of 100nm-wide LOR. Because this "T" shape could not survive the fast rotation of the spin coater. What is your way of drying the chip without breaking the bridge?

    Ron Reiserer · Vanderbilt University

    Damage is often caused by surface tension on such fragile structures so even is you just let the rinse solution evaporate you can see some damage to the structure. Is it possible for you to reduce the undercut on your LOR to improve structure integrity? Try to get 100nm undercut instead of 200nm.

  • Shi (Kevin) Feng asked a question in Bacterial Cells:
    Is there a way to wash off the absorbed phage from infected bacterial cell and extract phage DNA that injected into bacterial cell?

    I have a phage resistance bacterial strain. And I want to see if phage can inject their DNA into the cell. So I need to extract phage DNA that has been injected into the cell (if there is any) but not phage DNA that is in phage which just attached to cell surface.

  • Can we use two tested scales to develop a new scale?

    Using technology acceptance models like UTAUT and DeLone & McLean/Wixom Todd, I am trying to develop a framework for Social Construction of Digital Library. I have added 3 variables in this new factor structure. Can CFA alone will be sufficient to check its validity? As EFA is practically not possible with a large number of items in the questionnaire. Also, as it is said that while adapting existing scales EFA is not necessary. But in this case, I have added a few variables to the existing scales. Please suggest and provide references.

    Nripendra Singh · Jaypee Institute of Information Technology

    Thanks Eve. The information/reference will be extremely helpful. Also, your idea of contacting the authors. I will certainly do that. Thanks again. Nripendra

  • What's the difference between vaccinating between for Newcastle's disease virus and injecting NDV for an immune response?

    Avian Immunology study looking at application of light during incubation for laying hens

  • Any tips on using EstimateS software to compare locations in terms of shared species?

    Hi, I'm trying to use EstimateS software to compare two locations in terms of shared species. I am unsure however in what format to upload the data - I'm currently uploading it as a multiple sample set in a single spreadsheet, but I'm worried that the software is only comparing sample pairs within locations rather than between locations. Does anyone have any experience with this? Also, any advice on how to interpret the output would be appreciated.

    Esmaeil Sheidai Karkaj · Gorgan University of Agricultural Sciences and Natural Resources

    The PAST software may be useful for your problem.

  • Andrei Rogoza added an answer in Solvents:
    Where can I find CO solubility in acetonitrile?

    Could you please help me with CO (carbon monoxide) solubility in acetonitrile?

    I have googled it, but the best I can find is IUPAC solubility data series V43, which seems having not included CO solubility in acetonitrile yet. I have also checked "Solubility of Hydrogen, Carbon Monoxide, and 1-Octene in Various Solvents and Solvent Mixtures", which has not mentioned this system either.

    I will appreciate if you can help me with it. Thanks!

    Andrei Rogoza · Irkutsk Institute of Chemistry of the Russian Academy of Sciences

    http://pubs.acs.org/doi/abs/10.1021/ie0601091?journalCode=iecred - Table 5

  • Janiece Binns asked a question in Nursing Education:
    Nursing Care Plans Rubric?

    Hi, I'm in the process of working on my Capstone for my Master's in Nursing Education. I would like to create a standardized rubric to use across all three levels of clinical, and I need 30 research articles to support it. Does anyone know of any good resources? 

  • Meysam Motahari asked a question in Vensim:
    How to link Vensim Model to MATLAB software without interruption process, until obtained optimum data?

    I am working on an optimization project in which uses Vensim model. The data must be transfer from Vensim to MATLAB software and those outputs (by text format) must be import from MATLAB to Vensim. As you know, this will be continue and make a repetitive process from Vensim to MATLAB and vice versa to get optimized answers. I want to know it is possible to link Vensim and MATLAB by this method? Please help me in this problem.

    Best Regards

  • Is anyone familiar with double anti-virals for Chronic Hepatitis B?

    Does anyone have experience with double anti-viral therapy(Tenofovir + Entecavir) for Chronic hepatitis B? And when do you usually discontinue? Anti-HBe formation and viral suppression are frequently seen soon after initiation..but Anti-HBs formation, anyone seen that with double anti-virals? If yes then after how long?

    Syed Hunain Riaz · Allama Iqbal Medical College

    Well thanks for your worthy opinions...i guess this is a unchartered territory and maybe there will be some work on it in the coming time. Luckily resistance against entecavir and tenofovir is not rampant