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  • Guerrero Fajardo asked a question in Sonochemistry:
    Mesoporous carbon as catalytic support in sonochemical transestrification

    Currently, we are working in heterogeneous catalysis for biodiesel production using sonochemistry as energy source for transesterification reaction from jatropha oil but what happen with the catalyst structure specifically mesoporous carbon used as support of La and Zn oxides? Anyone has investigated this topic? Thank you for your collaboration.

  • Who owns patients' health information?

    According to the Freedom of Information Act, American patients can access their health information upon their request. I wonder if there is a global consensus over this issue? Do other countries have a similar legislation?

    In my country, doctors can refuse to show the patients their own information. They believe and say that the doctor and not the patient owns the patient's information. Is it legal? Is it ethical?

    ps. By "owning the health information" I mean "the right to read, copy, or keep a copy of everything written in the patient's record".

    Vera Barretto Aguiar · University of São Paulo

    Code of ethics
    Sealed to the doctor
    Art. Deny 88, the patient access to their medical record, fails to provide you with a copy upon request, as well as help give you explanations necessary for the understanding, unless occasioning risk to self or to others.

  • Does someone know a good sistem for screening "in vitro" to perform selection based on the folding properties of proteins?

    What are the major differences between protein unfolding and misfolding? And how can I pick up the most thermostable proteins?

    Lucas F. Ribeiro · Johns Hopkins University

    Thank you Adam. But I'm thinking about a library scenario (e.g. phage display), how can I select the best variant in a molecular level using ThermaFluor? I mean how could I be sure I have a single variant in each well of the plate? I'm sorry, maybe that is a stupid question, but I'm not familiarized with this methodology for screening libraries.

  • Angela Stanton added an answer in Ethics:
    Do you agree there is a decline in the ethical values in the field of medicine?If so what are the contributing factors?

    Ethics is an important element in the field of medicine, and it is astonishing to note that is a constant decline over the period of years, it is a must to address this issue to preserve the field from further deterioration. 

    @Julian, I sent you an email. :)

  • Zoltan Kish added an answer in Industrial Chemistry:
    What are the best conditions for producing diesel oil from catalytic pyrolysis of used tires?
    I am interested in doing some research regarding the best catalyst used in the pyrolysis process, to cut down the time of reaction and to get a high product of diesel oil.
    Zoltan Kish · Elementa Group Inc.

    The produced pyrolysis oil from tire is a complex mixture of substances containing saturated, unsaturated, aromatic and oxygenated hydrocarbons, water, sulfur based compounds, carbon, and other inorganic compounds. The pyrolysis oil could be very acidic and unstable. Therefore, the pyrolysis oil is not suitable to use directly as diesel fuel.

  • Leisa Perch added an answer in Resilience:
    Resilience or vulnerability? How to focus the debate on disasters?/ ¿Resiliencia o vulnerabilidad? ¿cómo enfocar el debate sobre desastres?

    In recent years, the term resilience has gained importance in the literature on climate change replacing the concept of vulnerability which, for several decades, allowed to reveal the social origin of disasters but, How can the participation of society can be addressed in each of them? Or are they just antonyms?

    En los últimos años, el término resiliencia ha cobrado importancia en la literatura sobre cambio climático, reemplazando al concepto de vulnerabilidad el cual, desde hace algunas décadas permitió revelar el origen social de los desastres, pero ¿cómo se puede abordar la participación de la sociedad en cada uno de ellos? O ¿simplemente son antónimos?

    Leisa Perch · World Centre for Sustainable Development

    Hi Judith,

    In my perspective they are linked and they are not opposites as that would assume that because you are resilient you are not vulnerable and that is certainly not the case.  Resilience is the capacity to withstand the shock and still keep standing and even begin to thrive again. Vulnerability is a continuum and can be more and less acute and is defined by exposure and sensitivity.

    There is a wide literature and Dewald has referred you to some of them. I would also suggest reading the IPCC Chapter 13 on Poverty and Livelihoods (see attached) where there are also some very useful graphics on what this means in a dynamic sense.

    I would also suggest some additional reading on the issue including the following:



    Karen O'Brien is particularly good on issues of Vulnerability as is Neil Adger.

    There is also good literature on social vulnerability including in the Caribbean and defining what that means and Godfrey St Bernard has done or written quite a bit of that work along with Asha Kambon.

    I also talk about this in a broader sense of how economic macro realities generate social vulnerabilites in this paper with a former boss. See the second attachment.

    I hope this helps.



  • Josimara Rondon added an answer in Invasive Plants:
    Is there any evidence when an invasive plant impacts the soil seed bank by changing soil nitrogen content?

    I wonder whether invasion of a N-fixing alien plant would have any effect on soil seed banks. Also, what are the most common mechanisms of influencing seed banks by invasives?

    Josimara Rondon · Universidade Católica Dom Bosco (UCDB)

    Adenocalymma peregrinum is an invasive species in savannas brazilian. and alter soil nitrogen. This species cause invasibility biological. Enzimes metabolizing amonium and nitrate in the soil. 

  • Fred Ribich added an answer in Psychology in IT:
    Can anyone assist with a problem with a list of teaching strategies and methods applied in stimulating psychology course students to activity?

    The project I am involved in is about indicating the number of teaching strategies used by academic teachers providing seminars for students taking psychology course.

    Students will be informed at the beginning of semester about the variety of available teaching/stimulation methods and then they will rank their preferences. After finishing seminars they will rank a)how much the strategies were used and b) How effective these strategies were found to be in learning process and developing skills ?

    Maybe you have conducted/ or could suggest any research or article concerning the issue of stimulating psychology course students to activity and/or the efficiency of specific methods in teaching.

    Fred Ribich · Wartburg College

    For Neletta Fredelake and others who may be interested ...

    Amazon.com has copies of Volume 4 of Ludy Benjamin's Activities Handbook; try this link:

  • John S Wishnok added an answer in Polyurethane:
    Challenges with NO releasing Polyurethanes

    What do you think are the biggest challenges related to Nitric oxide releasing polyurethanes? What are the possible solutions to overcome/ improve them?

    Short statements without explanation will do!

    thanks for your time



    John S Wishnok · Massachusetts Institute of Technology

    What is your real question?  What problem are you trying to solve with nitric oxide-releasing polyurethanes, and why are you working (or wanting to work) with them?

  • What is the difference between differential and integral forms of Navier-Stokes Equations and their usage ?

    Hello everyone,

    I am reading CFD by John D. Anderson. I understood the derivation of different forms of Navier-Stokes equations. But it is still unclear for me what is the fundamental difference between Integral and differential forms of the Navier-Stokes equations. It is also not clear for me where are these forms used ?

    I always see all the explanations based on the Differential forms so I am wondering if the integral forms are used ?

    Another thing : Please correct me if I am wrong ::

    The conservative and non-conservative forms are called like that because, the conservative forms are derived from a conservation law and the non-conservative forms are not.

    N. M. M. Cousin-rittemard · Université de Rennes 1

    Dear Aditya,

     Actually, in the frame of continuum mechanics, the integral forms of the equations of conservation of mass, linear momentum and energy are firstly derived. Of course, there is no trick  : if you consider a newtonian fluid for instance, the angular momentum conservation is taken into account by requiring that the stress tensor is symmetric. For this purpose (i.e. derive the integral forms), you can adopt lagrangian point of vue by means of the Reynolds transport theorem on the one hand. And, on the other one hand, you can either adopt the eulerian point of vue, considering a control volume V. The derivation of each integral form and the inference of the differential forms of each equations of conservation are really straightforward  (p57, 2.19 e.g. ).

    You are right about "conservative", even the use of "conservation" of linear momentum is puzzling at first ; it is not conserved unless the resultant force is zero, isn't it ? In conservative forms, rho, rho u and rho e are unknowns. They are used for compressible flows when neither rho is constant nor div u is zero). The convective part of the total derivative is of the form : "divergence of something". And, at that point, you understand why these forms are called "conservative".

    Regarding your second question, I would add a very simple example of an « every-day-use » of the (euler) integral form of linear momentum which is used to carry out an estimation of the resultant force in a Venturi or in a curved pipe.

    Hoping that it could help.

  • Leisa Perch added an answer in Social Protection:
    Do you know of effective social protection tools that have been used to face natural disasters?

    I am working on a toolkit of social protection (SP) policies and programmes in Latin America and the Caribbean, and I am interested in knowing more about SP tools that have proved effective to protect individuals, families, and communities from the consequences of natural disasters (such as earthquakes, hurricanes, floods, etc.), especially in a developing country context. Thanks.

    Leisa Perch · World Centre for Sustainable Development

    Hi Simone,

    Am familiar with your work. There are quite a few approaches that are relevant including by ODI and IDS on adaptive social protection - Lindsey Jones and Sabattes-Wheeler have been doing some interesting work on these issues including some more recent work specific to the agriculture sector. In terms of tools - there are a few  examples in Asia - particularly Sri Lanka, India and Banglasesh that included selfhelp groups, microinsurance and microcredit for rebuilding assets. I am from the Caribbean and worked on some of these issues in the past and continue to look at them in the context of reducing social risk and rish sharing mechanisms.

    Cash transfers, food for work programmes, work programmes have all hadsome level of success depending on the target audience, the length of time they are put in place and effective management and oversight as well as data collection.   In Haiti this was done with some success after the Earthquake and is documented in several UNDP reports.

    I can share documents with you that I am aware of if you like.

    I think it would be useful to add tot the toolkit examples from Africa and Asia which can also strengthen the SP practice in this context in LAC and would build useful SSC links particularly between communities and actors.

  • S. V. Seriy added an answer in Annealing:
    What is the possible reason of decreasing contact resistance between metal/graphene and graphene/TMDS?

    When we measure the drain source  current by applying drain source voltage of graphene contacted MoS2 tranistor before annealing and after annealing, we observed significant decrease of contact resistance after annealing compare to before annealing. What could be the appropriate reason for this observation?

    S. V. Seriy · University of North Texas

    Reason - Structural rebuilding in the metal, metal grain coarsening

  • Does quantum field theory resolve the measurement problem in quantum mechanics?

    Recently I read a paper titled "Quantum field theory solves the problem of the collapse of the wave function" by Alexey V. Melkikh (arXiv:1311.0205v1 -
    quant-ph). An earlier paper on the same topic is " Measurement problem in quantum mechanics" by Michael Danos & Tien D. Kieu (Int. J. Mod. Phys, vol-8, p-257, 1999). Both these papers claim that the measurement problem is completely resolved with in the framework of quantum field theory because it incorporates both the particle and wave aspects, while quantum mechanics deals only with the wave aspect. While the arguments in these papers are convincing, I would like to know the general consensus on this topic.

    Charles Francis · Jesus College, Cambridge

    No, you have only shown the prediction of BM in two different ways, because you did not treat the quantum mechanical formulae in a way which is legitimate for quantum mechanics. I have shown an example which make it explicit that QM does give a different prediction.

  • Has anyone encountered problems with blanks when analyzing Quaternary Ammonium Compounds by LC-MS?

    Atfer analyzing water extracts containing QACs by LC-MS, the negative controls came back as positive suggesting ion source contamination. Any comment on this problem would be appreciated.

    John S Wishnok · Massachusetts Institute of Technology

    What can help is to avoid injecting concentrations of standards that are well (as in way!) above the levels of analytes that you see in your samples.

  • Can you answer my question on linearity in QED?

    If we have two classical electromagnetic fields linearly correlate (the ratio between their intensity is a real number) it is necessary that the quantum electromagnetic fields which “correspond” to the two classical fields to be also linearly correlate (the ratio between the creation and annihilation operators which represent the two quantum electromagnetic fields (which at the classical limit becomes the above mentioned classical fields) to be real numbers also)?

    Charles Francis · Jesus College, Cambridge

    I think the relationship is more subtle, and I can only give an answer in the context of a particle theoretic treatment of qed. Quantum fields are operators and do not themselves change, but what they act on must change. I can't describe a correlation between the numbers of photons contributing to the fields because there is no photon number operator. There is a correlation between the likelihood of creation and annihation of photons, which must come down to a correlation between the amount of the charges creating and annihilating photons (meaning the number of charged particles creating the field.

  • Mark H Wright added an answer in SNP Genotyping:
    What SNP genotyping method should I use?

    I want to genotype 300 specific SNPs (spans across multiple chromosomes) in about 600 human patients. What genotyping method should I use?  The DNA is extracted from human blood, and I need very accurate results.

    Please advise. Thank you.

    Mark H Wright · Stanford Medicine

    It depends on your budget really, and what equipment you have access to assuming you only want to design the assays and not buy a platform. Only 600 samples takes microarrays off the table I think. Sequenom is probably better at this range. Please keep in mind that regardless of your choice of platform, it is not likely that all 300 SNPs will convert (work at all), and those that do convert will not all work with the same accuracy nor will they always produce a genotype in every sample (call rate). The only way you get really robust arrays or multiplex SNP assays is to iteratively design them - make a design, test, remove SNPs with poor accuracy, poor repeatability, or low call rates, replace with other candidates, repeat, until over 99% of the SNPs are giving over 99% accuracy in over 99% of sample, but you (or your budget) decide when things are "good enough". Thus, if you know of "perfect markers" for your SNPs of interest - anything in perfect LD (use r^2 not D') with the SNPs you are interested in, you might want to line those up as additional candidates to replace any of the 300 SNPs you can either not genotype because they fail the platform's chemistry requirements, score low on the manufacturer's assay design tool (e.g., Illumina's ADT or equivalent), or empirically fail tests. 

    Sanger sequencing has the advantage of redesigning PCR primers, sequencing primers, and re-running failed samples on a per SNP basis, as opposed to designing a 300 SNPs at once multiplex assay. Oligosynthesis is where everything becomes expensive, and why many assays start to get very cheap *per sample* once you plan to do >1000 samples. Ordering PCR primers is the same - you can get a lot more for very little additional cost over the lowest cost option.

  • Is anyone familiar with western blotting?

    I am using 5% milk for blocking and I want to dilute the primary ab in 3% BSA. Is this Ok or should the blocking solution also contain BSA?

    Second question. Do I have to wash with TBST after blocking or can I add the primary to it directly?

    Suggestions would be appreciated.



    Emilia Joanna Orzechowska · University of Warsaw

    Hi Jaya! I very often freeze antibodies diluted in 5% milk and don't have problem with reuse them. Of course it depends on the antibodies but it's rather common practise. Good luck!

  • Marko Stijić added an answer in Innovation:
    Does anyone have experience with Kirton Adaption Innovation Inventory or some other instrument which measures continuum adaptability-innovativness?
    I am planning to conduct research on enterpreneurial students intentions and enterprise, in general. Since Kirton Adaption Innovation Inventory is licensed, I would appreciate if someone could recommend me some other similar (and free-of-charge) instrument. Thank you in advance.
    Marko Stijić · University of Zadar

    Thank you very much, Britta!

    Definitely helpful.

    Best! :)

  • Mohamad Fahrurrazi Tompang asked a question in Methods:
    Method for bioethanol estimation

    What is the best method of determining bioethanol by dichromate which is stable the most?

  • Antonio Dal Canton added an answer in Arteries:
    Does anyone have experience with 2 Kidney 1 clip technique?

    I am trying to perform a surgery for 2k1c method. Does the kidney size gets reduced after clipping it or does it remains same. Can we use some other thing to occlude renal artery other them silver clip and do we need to partially or completely block the artery.

    Antonio Dal Canton · University of Pavia

    I used the model some 25 years ago to induce hypertension in female rats followed by pregnancy.  In pregnant hypertensive rats I investigated glomerular dynamics with micropuncture and water and salt balance. The study was published in American Journal of Physiology 256: F728-F734, 1989.

    I had the silver clips by DeJong, Netherland, as a personal courtesy. In the time lapsed between clipping  and sacrifice,  about 5 weeks, I did not observe a visible difference in size between the kidneys. I do not remember the size of the clip but the obstruction was partial. Clips of same size had different effects in rats, some developed severe hypertension, some remained normotensive. The model is simple, the surgery is easy   as I can remember, some trouble could be met in dissecting the artey from the vein. The bothering aspect was BP repeated measurement. We used a tail cuff and the unavoidable collateral effect, soon after turning the rat on its back and closing in a strict cage to avoid movements, was a ...burst of bullets ...not killing but ...better use gloves.

  • Kai Wang added an answer in Silicon Solar Cells:
    Why are silicon solar cell p-layers is thicker than n-layers?

    In silicon solar cell p-layer is thicker than n-layer, why?

    Kai Wang · University of New South Wales

    The reason for one thin layer and one thick layer is that diffusion is performed upon the thick layer to fabricate a p-n junction. Shallow junction would help with carrier collection as carriers generated in the thin layer don't have to diffuse too long before they can be collected by the junction (I am talking about conventional front junction solar cells). Besides, shallow junctions are easier to achieve as they require less diffusion time, which is industrially more viable.

    The reason for using p-type substrate is because phosphorous diffusion is easier compared with boron diffusion and the minority carrier in p-type base is electron, which features a higher mobility. However, n-type substrate is more tolerant to chemical and crystallographic defects, which implies high potential to achieve high efficiency solar cells such as Sunpower IBC (Lab) and Yingli Panda (Industrial).

    I don't agree with Abdulkadir on "If you demand more photocurrent, you should keep your semiconductor material as thinner as possible Because of according to peer lamberts law penetration depth of the material is directly related to absorption coefficient and band gap of the materials." because too thin substrates would lead to the loss of long wavelength photon absorption, which reduces short-circuit current (bad QE at long wavelength).

    I also don't agree with Abdelhalim on "The n+ top layer acts as an emitter layer. For optimum functioning , it must be heavily doped and thin to have a very small revere saturation current and decrease the absorption of the ultraviolet photons in it since it has a dead layer near its surface." as dead layer is caused by heavily doped emitter. Indeed, heavily doped emitter would reduce series resistance yet it causes the loss of short wavelength photon absorption (bad QE at short wavelength). A good idea to achieve both high QE at short wavelength and low series resistance is to use selective emitter, where you only doped the emitter underneath the metal contact heavily and leave other emitter regions lightly doped. This can be achieved using spin-on-dopant and subsequent laser doping, which UNSW has carried out a lot of research on.

  • Md. Rezaul Islam asked a question in Hydroponics:
    Problem with RNA extraction under Hydroponic system

    Recently I applied stress on Jute seedlings under Hydroponic system. Initially I used to get good RNA concentration after extraction but now the concentration is too bad to work in downstream steps. Do you have suggestions what could lead to the low concentration of RNA? How can I solve this problem to get high quality RNA?

  • Transfer voltage for western blots.

    I'm trying to transfer a low molecular weight protein from a 15% SDS-PAGE gel to a .45um PVDF membrane.  I've heard many people suggest using a .20um membrane but many others suggest that it is possible on a .45um membrane.  I typically transfer at 100V and 400mA for 1 hour or 114mA at 35V overnight (~16h).  Does anyone know which would promote better transfer for low MW proteins (~7kD).  I have ponceau S staining results for the 1 hour transfer and they look good but I don't see any low molecular weight bands for my samples (C6/36 cells) but I always have a good color band for my ladder at 10kD. 

    Emilia Joanna Orzechowska · University of Warsaw

    Hi! I completely agree with Fabianno. You can also check if you don't have any color bands from your marker on the Whatman's paper (the small one of course). It's an easy way to see if the transfer time isn't too long.

    Good luck! :)

  • How can you calculate dn/ds manually from multiple sequence alignment?

    I read from some papers that they take some indels in the non-coding regions as synonymous and take some indels in coding regions as non-synonymous. And calculate the dn/ds to detect positive selected indels. But I did not find a software for that, and I also did not find a document for calculate dn/ds manually from multiple sequence alignment, so I could write code myself. Could some share me with some documents please?

    Brian Thomas Foley · Los Alamos National Laboratory

    There are problems with counting insertion/deletions as a measure of evolution at all, let alone deciding how they contribute to a dN/dS ratio.   I would not recommend writing your own code, when there are already several very good program packages available for studying positive and negative selection pressures on protein-coding DNA sequences.  The datamonkey/HYPHY package for one example.  Or SNAP.

    The problem with insertions/deletions is how to "count" their contribution to the evolutionary distance.  Is a 21-base (7 codon) insertion one event or 21 events?  Is a 21-base duplication of a sequence the same as a 21-base insertion of unique DNA?  Is a stutter ton insert or delete an instance GAA of a simple repeat GAAGAAGAAGAA the same as an insertion or deletion of a codon in a non-repeat region?

  • What is the best technique for improving wear resistance on stainless steel without compromising the corrosion performance?

    See above

    Everardo E Granda-Gutiérrez · Corporación Mexicana de Investigación en Materiales

    Ok, thanks.

    Now more data: the application is for a bearing with oil seal in a device with some content of H2S.  The material is a precipitation-hardening alloy.  

    I tried nitriding before with good results but it is not enough to avoid failure (hydrogen embrittlement).

  • Manuela Morato asked a question in Kit:
    ELAST amplification kit

    Did anyone use ELAST amplification kit? Did you use any blocking solution? When?

  • James F Peters added an answer in Papers:
    Should we question the credibility of international conferences?

    We see most of international conferences accept more than 90 percent of the papers that they receive regardless of the quality of the papers or plagiarism possibilities. Shall it make us think that the conferences are only business?

    James F Peters · University of Manitoba

    Above all, it is @Kamal Eddin Bani-Hani and @Fairouz Bettayeb who point to the hallmark and vitally important feature of international conferences, namely, meeting peers, exchanging ideas and starting collaborations.     There is no question that attendance at least one international on a regular basis is important.    The question to ask then Which international conference should one choose? 

  • Anita Taboh added an answer in Children:
    Can clinicians working with foster carers looking after babies and young children comment about the approaches they are using?

    I would be interested to hear from clinicians working with foster carers looking after babies and young children about approaches they are using

    Anita Taboh · Walden University

    another model that is very good is that of Multidimensional Treatment Foster Care for young children.  Leans more toward learned behavior than medications.  Quite effective, if you google MTFC, you can learn more about it.

  • How can I asses the nitrogen fixing activity of hundreds of bacterial colonies isolated from rhizospheric soil?

    We are interested in getting rhizosphere bacteria with plant growth-promoting activities. We got hundreds of bacterial colonies from environmental samples and we must now evaluate nitrogen fixation in them. Does anyone know selective microbiological methods for these activities?