Q&A

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  • Mostafa Eidiani added an answer in DIgSILENT:
    How can I simulate frequency load shedding using digSILENT?

    Is there any procedure for that ? Can any one help me with case study?

  • Roberto Bernetti added an answer in ANSYS:
    How do I apply SAC loading protocol 1997 in ANSYS apdl?

    SAC loading protocol is a graphical representation of deformation against cycles. on y axis is the peak deformations and on x axis cycles are plotted. Please help me with the loading commands in ansys.  

    P.S I'm a beginner in ANSYS apdl. 

    Roberto Bernetti · Ministero dell'Istruzione, dell'Università e della Ricerca

    which kind of error?

  • Benamí Barros García added an answer in RStudio:
    Do you know how to set things up for text analysis (with Cyrillic characters) in R under W8.1?

    I have some issues to get it to work and I would like to know how to deal with Cyrillic data and corpus files with R (RStudio) under W8.1. I know this is not the best OS to run R, but I would appreciate any suggestion to solve the problems. 

    Thanks! 

    Benamí Barros García · University of Oxford / University of Granada

    Thanks for your answers! 

    I think Fiorella is right regarding UTF-8 and RStudio for Windows. It seems to be easier to run Wubi or install Ubuntu as dual-boot system. Gries (2013: 166-172) proposed a model for working with non-English non-ASCII data on Ubuntu that seems to work properly. 

    Many thanks! 

  • Brandon Brooks added an answer in rRNA:
    Is it possible to use NGS to sequence almost full length 16S rRNA product obtained from regular PCR amplification with general primers e.g. fD1 & rD1?

    -Using variable regions do not have a good taxonomic resolution

    -Is it possible to create NGS libraries from this kind of amplified DNA (∼1500 bp) instead of using total DNA or the variable regions of 16S?

    Brandon Brooks · University of California, Berkeley

    There is a way to assemble the entire gene from an amplicon, as you described, using the EMIRGE software (http://genomebiology.com/2011/12/5/R44). I used the software for a recent project (http://www.microbiomejournal.com/content/2/1/1), as have other folks. If you need the full length gene, it's definitely worth looking into (depending on your application).

  • Zeinab Hazbavi added an answer in Soil:
    I need some information on how soil amendments were used or some information about method of application of soil amendments?

     I start study of soil amendments application type and preparation forms.

    Zeinab Hazbavi · Tarbiat Modares University

    I want to study about soil amendment application on soil and water conservation, soil erosion and runoff control.

    Thank you

  • Amin Saburi added an answer in Hearing Loss:
    Is anyone interested in becoming a co-author on projects on skin lesions in liver disease, infertility, hearing loss imaging, and others?

    Dear Colleague

    I seek for a collaborator for preparing a review article.

    Please send me a massage if you have sufficient and enough time and experience in medical writing.

    these projects will be about :

    1- Skin lesions in liver diseases

    2- imaging in infertility

    3- imaging in children with hearing loss

    4- cochlear implantation outcome in terms of etiology of sensori-neural hearing loss

    5- imaging in pulmonary complications of mustard gas exposure

    these projects are ongoing and some steps were completed!

    regards

    Amin Saburi · Baqiyatallah University of Medical Sciences

    In these review project, We would like to prepare a systematic or narrative review article based on the mentioned titles. After choosing a recommended title, we will gather the data (systematically or not), then regarding to a designed protocol, the data will be selected and interpreted. Finally, write draft. I have enough experience and some research articles in all recommended topics at above. Therefore, I can lead these projects. when you accept my invitation, I warrant that your name shall be involved in author lost if you collaborate in all steps of project. You, as a co-author, should help to gather and acquire data, search literature, select proper data, and help in medical writing. I will give you some topics, heading and sub-heading and write the draft together.

    any question?!

  • How is the RNA quality from the samples dissected by the laser capture microdissection?

    Hi, Has anyone done dissection (e.g.,brain dissection) using the laser capture microdissection, and done the qPCR analysis on the samples? How was the RNA quality and which kit did you use?

    Yelena G Golubeva · U.S. Department of Health and Human Services

    Hi Soulmaz,

    With the properly collected and prepared samples mouse brain LCM samples have RIN 7-8.2. Extraction with RNAeasy Micro kit from Qiagen, elution volume 16 ul, RNA QC on Agilent Bioanalyzer Pico Chip (it also gives you a concentration estimate with 20% range). I calculate number of slides to be pooled for one sample based on the area of LCM target at 8 um FFPE section or 10um frozen section. A little pilot up front for the yield estimate will help to get a sample with enough RNA for your downstream. LCM targets can be accumulated in buffer RLT on wet ice (I routinely transfer targets to a 1.5ml tube, though it depends on your LCM instrument and consumables) for 4 hours before final vortexing. You can also divide 350 ul (protocol volume) of buffer RLT by the number of slides you are going to dissect, and lyse targets from one slide, keep them frozen until the extraction when you can combine all the lysates for single extraction. As for FFPE samples, RINs are usually around 2-4 and greatly depend on the quality of the blocks, and with human tissue you will have a lot of variability.

    Good luck,

    Yelena 

  • Theo K. Dijkstra added an answer in 2SLS:
    What is the main attraction behind using GMM instead of 2SLS?

    Is it just endogeneity? What do you think if Cov(x,u)=0 then the reason of using GMM instead of 2SLS is same as using MLE instead of OLS??

  • Alican Aktağ asked a question in Rare Earth Elements:
    Could you please suggest me a book or document about partial melting degree calculation via rare earth elements data?

    I used the Shaw (1970)' s partial melting degree calculation (Ce-La, La/Nd-La) and got some results, and want to compare my results with other calculation methods (Rare Earth Elements). Thanks for your interest.

  • Besides publishing in journals and writing books, what ways help promote ideas that have been researched?

    I have just gotten published a book on transpersonal experiences surrounding death.  These include near-death visits, near-death experiences, out-of-body experiences, death bed communication, after death communication and other related phenomena.  The books that prepare health professionals to assist patients and family members close to death who have these experiences are woefully lacking in discussing these phenomena.  Millions of people have these experiences but those helping them often are confused or conflicted about how to respond. 

    Aleksander Kobylarek · University of Wroclaw

    You can publish in fragments in social networks for researchers like researchgate, academia.edu, figshare. It could be useful to establish a blog or an internet site on facebook and to collect the people intrested in your main topic. You can also arange meetings, using the power of the NGOs, which might be interested in the topic of your research and in results of study

  • Mostafa Eidiani added an answer in Power Systems:
    Where can I find data on power system load and corresponding weather data (temperatures, ...)?

    I need this for forecasting.

  • Nikolina Bubica asked a question in Online Teaching:
    Can someone direct me to any research in teaching Scratch programming to 10 year old children and using online teaching materials to support it?

    I'm preparing online teaching material for learning scratch programming to 10 year old childred and I would like to hear about other experiences? I wonder if I could motivate them more with online materials which are prepared for them and are available to them in any time.

  • Where could I get the CH3NH3SnI3 cif file ?

    I have downloaded the cif file from the COD website, but found that the hydrogen atom is not included.

    Alexander S. Filatov · University of Chicago

    Did you check Cambridge structural database? But it is possible that the structure was reported without H-atoms, especially if it is an old one.

    What do you want to do with the structure? Make a picture or setup coordinates for calculations? Then, just use software, like Mercury, which will add H-atoms in calculated positions. You can then save it in any format you like.

  • Amos Onyedikachi Anele added an answer in Induction:
    Any advice on inductance measurements for SynRM?

    Really, the measurements of dq- axis inductances of the SynRM is more complex in case of including the magnetic saturation and iron loss.

    In literature, there is several methods for measuring the dq-axis inductances of the SynRM.

    If someone can suggest a simple laboratory method to measure the dq-axis inductances including the magnetic saturation and iron loss????????

    Amos Onyedikachi Anele · Tshwane University of Technology

    Oh Okay! That is very good

    It is quite unfortunate that I am not able to provide any advise as regards experimental measurement for SynRM

  • Aleksandra Śmilgin asked a question in Infection:
    What are the most common ventroperitoneal shunt-associated infections and how to prevent them?

    What sort of prevention (if any) do you apply?

  • Peter G Hains added an answer in Proteomics:
    Number of biological/technical replicates in label-free proteomics?

    Does anyone know the minimum number of biological and technical replicates required to perform label-free proteomics analyses?

  • Valentin Danci added an answer in Physics Theory:
    Do you know of any case in which physicists accepted a basic theory based on a derivation from accepted theories, or its mathematical structure?

    Kuhn says leading physicists accepted Newton's theory of gravitation before astronomical measurements were accurate enough to decide the issue ["Structure of Scientific Revolutions" 1962]. Other than this aged example, is there any case in which physicists accepted a new or modified basic theory of physics based on a mathematical derivation from well-accepted theories, before direct empirical evidence was available? The Higgs boson and cosmic inflation have something of this flavor: these theories had substantial credibility before empirical evidence was available because they explained phenomena that were left unexplained by existing theories, but they were not fully accepted in the canon of physics.

    Valentin Danci · Science

    Akira wrote:
    "Newton's mechanics is all false. For example, when M and m attract each other with gravitational force, for m, M is approaching with acceleration Gm/r2 and for M, m is approaching with acceleration GM/r2. So when m and M are not equal you have a contradiction."

    I can show you why that is not a problem: let's say, an observer on the surface of the Moon watches how an artificial satellite of Earth is falling down from place A- its initial orbit, onto place B- the Earth's ocean.

    Now the question is: what values of accelerations does the observer on the Moon notice for the satellite, and what values of accelerations does he notice for the Earth?

    The answer should be obvious: the Earth practically doesn't have much acceleration imparted to it, while the satellite has more and more acceleration imparted to it; again, as both would be observed from the surface of the Moon.

    The explanation is that acceleration is not relative; it does not appear different when seen from different inertial systems, as it is a rate of changing velocity. And also, because it doesn't depend on the inertial system of observation, it is said that acceleration is an absolute quantity.

    That also means that 2 objects moving towards each other can have different accelerations respectively, each directly proportional to the forces they are subjected to, and each inversely proportional to the mass of the respective object.

    (I'll reply to the other issue about kinetic energy later today as time permits).

  • Why do we take very dilute solutions less than micro molar concentration for SERS measurements?

    I'm planing to measures the SERS by thiols stabilized gold nanoparticles.  

    Xiangcheng Sun · University of Connecticut

    High salt concentrations may destabilize and aggregate the gold nanoparticles. This will make the measurement of SERS effect difficult.

  • What is the functional group tolerance of DDQ?

    Hi all,

    When using DDQ (2,3-Dichloro-5,6-dicyano-1,4-benzoquinone) to aromatise a molecule, what kinds of groups have people found to be tolerated/not tolerated?

    Specifically I'm interested to see if anyone has used it in the presence of primary amines or BOC protected amines.

    Kirill I. Petko · National Academy of Sciences of Ukraine

    As I know acetylaminogroup do not die in some oxydative prcecces with DDQ (alkohol was oxydized to ketone acetyamino presents and not chanded, but at low temeperature (-20? may be). Adout BOC protected groups I personally only can say "I dont know" but there are some analogy between acetylamino and BOC protections

  • Time required for changes in surface and groundwater quality?

    Dear all:


    I am studying the effects of agricultural production and European agricultural reforms on surface water quality (nitrates and suspended solids). As my understanding, the effects of pollutants on surface water can be appreciated in much shorter time in surface water than in groundwater. However, I have not found a worth publication about that. Might you know something else about this issue?

    Olivier Radakovitch · Aix-Marseille Université

    The answer of Alper Elci is correct. The influence of nitrate and SPM will be direct in surface waters. For the groundwaters, solids will have no influence (except in case of leaching of adsorbed contaminants), and the time necessary for dissolved pollutants to reach the aquifer is due to  the infiltration rate, the depth of the water table and the retardation factor (the capacity of the soil to retain pollutant). It could be days, weeks or even decades ! So this last time will be very different from place to place, and I don't think that you will find a kind of compilation or review for that.

  • Which donor characteristics do you consider important when accepting an Isolated Small Bowel for transplantation?

    In the modern days there is a trend to push the boundaries and utilise more and more organs for transplantation. But how willing are you to accept Isolated Small Bowels with unfavourable characteristics? Can we push the boundaries in Intestinal Transplantation?

    Gerald Brandacher · Johns Hopkins Medicine

    I agree with Dr. Vaidya that the boundaries can be pushed in intestinal transplantation by individualized decision making for every single recipient and using donor criteria as surrogates but not dogmatic for either inclusion or exclusion. The willingness to accept isolated small bowel grafts with unfavorable criteria is probably most dependent on the recipient condition and underlying disease.

  • Peter Raymond Smith added an answer in Serum:
    Does anyone have experience with estradiol ELISA kits?

    Does anyone have any experience with or views on either the Arbor Assays Estradiol Serum EIA Kit Measure Free 17ß-Estradiol in Serum and Plasma or theBlueGene Biotech Sheep E2 estradiol (E2) Elisa kit . Both claim very good sensitivity ?

    Peter Raymond Smith · AgResearch

    Hi Anggadia,  in general we collect plasma, simply because it is suitable for most of our needs, we collect a lot of blood samples and the processing of plasma is quicker and simpler than serum.

  • Mostafa Eidiani added an answer in Simulink:
    Has anyone worked on "Double ended fault location calculations"?

    I am trying to simulate Double ended fault location calculation in Matlab/Simulink. I read some papers, and found that negative-sequence quantities are used for single phase-to-ground, phase-to-phase, and phase-to-phase-to-ground faults. Hence, in my Simulink model, I prepared a transmission line model using the distributed parameter line. I measured voltages and currents at both ends of the three phase transmission line. From these measurements I calculated the negative-sequence quantities. In the formula, total impedance of the line is used. My problem is that I don't understand which is the total impedance of the distributed parameter line? The per unit length for Resistance, Inductance and Capacitance are given in matrix form like R = [0.01273 0.3864], L = [0.9337e-3 4.1264e-3] and C = [12.74e-9 7.751e-9]. So from these quantities, how can I determine the total impedance which is used in the fault location calculation? I really appreciate your cooperation in advance.

  • 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.

    Wilfried Musterle · Max-Born-Gymnasium

    If there is a clear and coherent model we do understand the principles how consciousness emerge in the brain. If the principles are understood a functioning model could be build in many different ways because we do not build neurons but functional units which represents these principles. It is a question of will (and money).

  • Amechi Akwanya added an answer in Literary Theory:
    Can anyone suggest any material on archetypal literary theory?

    The aim is to assist in writing a dissertation

    Amechi Akwanya · University of Nigeria

    Northrop Frye's 'Archetypes of Literature' is highly recommended, and also The Great Code. K.K. Ruthven's Myth will also help.

  • G. A. Shitu asked a question in Precision Agriculture:
    Can precise system of farming help mitigate climate change?

    Climate Change adaptation and mitigation through Conservative Precision Agriculture

  • William Morello added an answer in Pediatrics:
    Can anyone provide a reference for ITP in pediatric age group?

    Do you have any new pathogenesis of ITP in pediatric age group.

    William Morello · University of Bologna

    RItuximba is the second line after high dose immunglobuline and steroids in chronic ITP

  • Irina Mikheyeva added an answer in Agar:
    Can anyone recommend a synthetic media agar recipe for Staphylococcus Aureus?

    Trying to limit available cys in media. 

    Irina Mikheyeva · Geisel School of Medicine at Dartmouth

    Thank you for your responses. Unfortunately, all those recipes use beef extract which is rich in amino acids and unsuitable for my experiments. I am not trying to cultivate or pick out S. aureus. I'm testing a mutations and need to limit the bug's available amino acid, cystine, to perpetuate stress conditions.   

  • S.Y.C. Catunda asked a question in Pdf:
    How to model the uncertainties related to electronic components tolerances?

    Standard uncertainty is the estimated standard deviation of measured values. However, the dispersions of electronic components values are specified by companies as tolerances in datasheets and do not bring information about statistics (moments, PDF) . How their uncertainties can be modeled?

  • Clement Oluseye Ogunkunle asked a question in Biochar:
    What factors are most important in choosing biochars for metal immobilization in soil?

    I want to choose some commercially manufactured biochars as soil amendment to immobilized heavy metal. The biochars are already characterized but I want to know the features to be considered in choosing the biochars. i understand that a good biochars for metal adsorption must have large surface area and high phosphate content/phosphorus. What are other features to considered aside the feedstock choice?