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  • Panayot Tanchev added an answer in Scoliosis:
    Is the scar scoliosis surgery important for the women's sexuality?

    The scar after the surgery of idiopathic scoliosis?

    Panayot Tanchev · Medical University of Sofia

    Dear Dr. King,

    Could you give us, please,  a link to the presentation of this interesting study ? 

  • Jeff C. Clements added an answer in Mentalization:
    Does Darwinian Evolution matter?

    He: Do you have anything to say about the evidence I provided?

    Me: Your "evidences" is simply a testimony. Give us solid proofs: 1) how matter came? 2) how matter became alive? 3) how matter became intelligent life?

    He: evolution says NOTHING about matter.

    Me: Physics studies matter, "evolution says NOTHING about matter". So evolution is not physical. It is "mental case". Do you agree?

    Jeff C. Clements · University of New Brunswick

    Firstly, your argument is flawed in that you assume that the study of physics (as a discipline) is THE definition of something being physical, and if something is not physical (i.e., studied via physical sciences), it must be "mental". This is simply incorrect. Secondly, "solid proofs" only exist in mathematics - science can never "prove" much of anything, yet provides evidence that strengthens or weakens the likelihood of a particular theory being true. In fact, the entire faculty of science rests on the idea that nothing can ever be proven definitively; but evolutionary theory is one of the few theories that is as close as we can get to proof in science.

    Remember, Darwinian evolution describes the origin of species, not the origin of life. It describes how living species change over time, not how they came to be. Although our understanding of how evolution works has changed since Darwin proposed his theory (for example, we now understand that it is populations that evolve, not individuals), many of the underlying concepts of Darwin's original idea remain true.

    As stated by your colleague, evolution does not directly say anything about matter - nor should it. However, that does not mean it is an imaginary phenomenon that is simply "mental" in its scope. There are many direct observations of evolution in action, dating all the way back to 1901 with Huge de Vries and his observations of the Evening Primrose. More recent work by Dr. Richard Lenski using  Escherichia coli is another fantastic example of observing evolution in action (I suggest reading Dr. Richard Dawkins' book "The Greatest Show on Earth" for an exceptional display of the evidence for evolution, including direct observations).

    Although Darwinian evolution in itself does not describe how life first originated (again, nor should it have to), there is evidence that provides some insight as to how life may have formed from a "primordial soup". Some fantastic work being done by Dr. Martin Hanczyc (http://flint.sdu.dk/index.php?page=martin-hanczyc) and colleagues suggests that life could very well have evolved from a complex mixture of chemicals under the right conditions. For simplicity, watch the TED Talk from Dr. Hanczyc below;  I've also included citations to a few of his peer-reviewed papers that will be of value to you. There is still much work to be done, but Dr. Hancyzc's work is starting to elucidate a mechanism(s) by which life may have originated from nothing. 

    Hanczyc TED Talk: 1. http://www.ted.com/talks/martin_hanczyc_the_line_between_life_and_not_life?language=en

    Hanczyc publications:

    1. Hadorn M, et al. 2012. Specific and Reversible DNA-directed Self-Assembly of Oil-in-Water Emulsion Droplets. PNAS, doi: 10.1073/pnas.1214386109.

    2. Horibe N, et al. 2011. Mode Switching and Collective Behavior in Chemical Oil Droplets. Entropy 13, 709-719; doi:10.3390/e13030709

    3. Hanczyc MM, and Ikegami T. 2010. Emergence of Self-Movement as a Precursor to Darwinian Evolution. OLEB 40(4-5): 383. Conference abstract.

  • Specialist versus generic psychiatric services for people with intellectual disability and a dual diagnosis of psychiatric disorder?

    Psychiatric services are differently organized in different jurisdictions for people who have an intellectual disability and psychiatric disorders. In the United Kingdom for example most of the mental health Trusts have some form of specialist service for this population. In North America there are not many specialist services and this population is served by generic services. I would appreciate if you can share your views about which type of service better serves this population. About 40% of people with intellectual disability have a co-morbid psychiatric disorder. It is not a trivial problem.

    Muhammad Ayub · Queen's University

    Rohit, Ian, Joanne and Mike thank you for your answers. I appreciate contribution to this discussion.


  • What causes HPLC pump pressure falls during injection?

    Hello, I have dual pump RSLC dionex 3000. Left pump connected to Vector PC post column derivatization. When autosampler inject, HPLC pressure pump falls down and rise again. During pressure falling derivatizer pump off and require to start on again. What could the reason be for this?

    Mahmoud Ali · PhD student in institute of Graduated Studies and Research, Alexandria, Egypt

    Thanks Karsten for answer. About the leakage, could leakage exist even there is no leakage indication or leakage massage on the instrument?

    The HPLC pressure falls to 0%

    The derivatizer pump switch off at less than 500psi and could not changed.

  • Can anyone help us to work with waspmote for soil moisture sensor?

    We would like to do research on soil moisture Sensor. We have some basic doubts on it. Is waspmote able to connect with any soil moisture sensor or is only the agriculture board which is designed for waspmote.

    Pradeepa Murugappan · SRM University

    Thank you prasanna,

    yes i discussed with supplier, he told its compatible with any sensor. And Libelium also have their agriculture board for various sensors like soil moisture, leaf wetness Etc... let see the results after our experiments...

  • Adam Lund added an answer in Disaster Medicine:
    Does anyone have information about disaster medicine/management education of undergraduates in local medical schools?

    I am trying to get a picture on existing programs (voluntary or obligatory) in DM education on medical schools.

    Adam Lund · University of British Columbia - Vancouver

    Disaster medicine education in British Columbia, (and the situation is similar across Canada per chats with my colleagues) is thin.

    There are a number of very interested individuals across the country, from a variety of professional backgrounds, who are active in promoting improved disaster prep, education, training, etc. However, like all things that don't occur daily.... out of site = out of mind, and the funding isn't there to do this work more than off the side of one's desk. 

    What is interesting to me is that we have a divide between Emergency Management and Emergency Medicine. With such similar names, you'd think they work very closely together. The Emergency Management community is very involved in professional preparation for disasters regionally affecting people, property and infrastructure, but there is very little funded collaboration time between them and the Emergency Medicine Community.

    There is an assumption that "the hospitals will know what to do", but the time, funding and effort to get disaster drills and "code orange" training off the ground precludes it in working professionals... the result, very little systematic teaching in disaster medicine. As such, the medical schools have no formal curriculum in disaster medicine and/or emergency management. They may get a lecture on it during an emergency medicine rotation, but this is not consistent.

    Locally, our Mass Gathering Medicine research team (http://mgm.med.ubc.ca) involves students and residents in participating in aspects of the planning for mass gathering and mass participation events. We very deliberately get them thinking about the logistics, power, water, sanitation, personnel, communication, transportation, equipment, resupply lines, and many other issues that mass gathering medical response shares with disaster medicine. Developing a more organized curriculum, and using mass gatherings as a "live fire" or "field" exercise is our future goal. I've attached an article that explores this further for those interested. 

    Canada is a very geographically large country with a very distributed population. Face to face training for specialized topics is prohibitive in this environment. An eLearning solution to Disaster Medicine Education is a topic that our team has explored in the past. During my residency, when 2 colleagues and I were working on our Masters, we piloted an online program to provide case-based disaster education for medical students and emergency medicine residents. We got great feedback on the National pilot, but the lack of sustainable funding to develop more modules eventually relegated it to the back-burner. 

    Back to your question, Luc... Canada does not have a robust model of education for disaster medicine in its Medical Schools. 

  • Can anybody suggest some role of apoptosis in viral replication?

    I want to know the possible importance of apoptosis in virus life cycles.

    Philippe Le Mercier · Swiss Institute of Bioinformatics


    we have some answer on our website: http://viralzone.expasy.org/all_by_species/910.html

    "Viruses from several different families are able to exploit their host’s cell death programmes so as to maximize viral fitness. Apoptosis activation via caspases offers several advantages for viruses. Indeed, it may facilitate progeny virion release after host cell death. Furthermore, during apoptosis, the entire content of the cell, including virions are packaged into membrane-bound apoptotic bodies that are taken by surrounding cells. This process limits the inflammatory response and allow viruses to spread without being detected. HIV protease directly cleaves procaspase-8 to promote apoptosis. HPV 18 E2 protein induces oligomerization of caspase 8 through direct interaction."

    the viruses we have ideitified to profit on apoptosis are:

    -HPV16 and HPV18
    (Papillomaviridae ,Alphapapillomavirus)
    -HIV-1 protease
    (Retroviridae ,Lentivirus)
    -Langat virus
    (Flaviviridae ,Flavivirus)
    -Circovirus PCV2
    (Circoviridae ,Circovirus)



  • Why do I find a high linkage disequilibrium in Arab-Barbe breed horses?

    but this breed is created 14000 years ago?

    Semir Bechir Suheil Gaouar · La boratoire Physiologie, Physiopathologie et Biochimie de la Nutrition, Université Abou Bekr Belkaid Tlemcen, Algérie et laboratoir Génétique Moléculaire et Cellulaire USTO

    Thank you for your contribution but my population it's not in endengered situation? I d'ont find the publication ho you said send me

  • Felipe De Souza Leite added an answer in Biophysics:
    What causes inelasticity or elasticity in molecules?

    Thanks in advance for your replies.

    Felipe De Souza Leite · McGill University

    In muscles, titin is the main responsible for elasticity in striated muscles.The paradigm is that at physiological lengths you wouldn't have unfolding of the elastic domains, yet you'd have straighten of certain domains, known as molecular springs. As the length of these molecular springs increase it would accumulate potential energy, forcing the molecule to return to the original length.   

  • Does somebody have a recipe for non-radioactive EMSA blocking and wash buffer?


    I want to use an Affymetrix kit for EMSA (AY1000) with biotin-labeled probes, but the blocking and wash buffers are already empty. Do you know the components of the buffers? I found so many different recipes, which make me confuse, because some contain BSA, SDS etc and others not!

    António Pedro Gonçalves · University of Porto

    Hi. Were you successful using the TBS-BSA as the blocking buffer? Thanks.

  • A. J. Baker added an answer in Heat Transfer:
    Suggestions for accurately computing heat transfer in super/hypersonic flow domains?

    I am working on a research project which involves simulating heat transfer in super/hypersonic flow domains by using commercial CFD solver. I do find it is a quite challenging task to accurately obtain the wall heat transfer rate in super/hypersonic flow domains. Could anyone give me some info regarding the governing factors of  heat transfer rate computing or recommand some helpful references relating to the same topic? Thanks!

    A. J. Baker · University of Tennessee

    Appendix B in "Optimal MODIFIED CONTINUOUS Galerkin CFD" (Wiley 2014, ISBN 978-1-119-94049-4) fully details a real gas weak form algorithm for hypersonic shock layer prediction.   Near wall resolution is absolutely critical - view Figure B.6 for cold and near stagnation wall temperature Dirichlet BC solutions.   The weak form "trick" for accurate flux computation at surfaces with fixed temperature is detailed at the end of Ch. 2.3 of the text.

  • How can we determine cognitive load level using eye-tracking measures?

    Fixations, saccades and pupil diameter are the most used parameters, but I haven't found references about how to analyze those data in order to accurately determine cognitive load level.

    If someone can suggest specific methodologies that are used to determine cognitive load level using eye movement measures, I'll really appreciate that. Thanks!

    François Courtemanche · HEC Montréal - École des Hautes Études commerciales

    Here is a good review on the use of pupillometry for the study of cognitive processing: Laeng, B., Sirois, S., & Gredebäck, G. (2012). Pupillometry. Perspectives on Psychological Science, 7(1), 18-27

  • Rationale for 1:2 ratio in Case Control studies?

    Hello Researchers,

     What are epidemiological and Bio statistics rationale for considering 1: 2 ratio in a case control study? How do I chose two controls per 1 case? 

    pls Help me,


    Branko Miladinovic · University of South Florida

    Matching increases the efficiency of the estimates if the matching variables are associated with both the disease and the exposure. Barring the cost and time limitations of including additional controls, there are two reasons  for considering higher matching schemes (ie. 1:2, 1:3..etc): 1) concern for sufficient numbers in stratified analysis; 2) the increase in power given the expected prevalence of exposure among the controls (see Hennessy et al. "Factors Influencing the Optimal Control-to-Case Ratio in Matched Case-Control Studies," American Journal of Epid 1999; 149(2))

  • Do you think that older people may benefit from phototherapy?

    Older people are often more exposed to artificial light because of mobility problems perhaps influencing mental states. For instance, lack of exposure to natural light might impact mental state.

    Do you think that older people may benefit from light treatment simulating expose to natural light conditions?

    Sundarapandian Vaidyanathan · Vel Tech - Technical University

    Neil Armstrong quote:

    "It's a brilliant surface in that sunlight. The horizon seems quite close to you because the curvature is so much more pronounced than here on earth. It's an interesting place to be. I recommend it."

  • Umut Cagin Ari added an answer in Sperm:
    Can you share which kind of separation technique you prefer for ovine, caprine and bovine semen for in vitro fertilization ?

    I have experienced that swim up technique for sperm separation during IVF in ovine was not suitable for ovine sperm? So I had to use percoll gradient (90 and 45%) for ovine sperm separation, although I used to use swim-up separation in bovine IVF. And I obtained good results with percoll gradient compared with swim up technique in ovine IVF. I want to know whether or not you have ever faced similar situations during IVF? Also what kind of separation technique do you prefer to separate  semen in species (especially goat, sheep and cattle) in IVF? Have you ever used one gradient (i.e. only %45) percoll technique? 

    Umut Cagin Ari · Kafkas University

    Dear Omer Ucar,

    Thank you for your knowledge sharing about percoll usage.

    Normally, I dilute percoll with 10x TALP solution, 9:1 ratio. Then I obtain 90%Percoll and if I want to use 45% Pecoll, I dilute again 90% Percoll with normal (iso-tonic) Talp 1:1 ratio.

    It is interesting way to obtain 45% Pecoll via dilution of (isotonic) TALP with 100%Pecoll. I think osmotic pressure of Percoll may be lower than iso-osmotic presure of semen. It may be detrimental to spermatozoa via hipo-ostmotic pressure of percoll solution. Do you face any problem when you use 45% percoll in your way?

    My best wishes,  


  • How should a hypothesis be formulated in a publication?
    If 1000 people would observe the same phenomenon 'C' and be asked to formulate a hypothesis 'C' to explain phenomenon 'C', what fraction of the observers would formulate hypothesis 'C' in exactly the same way, for instance with the same words expressed in the same order? Can the same hypothesis be represented with different oral or written expressions in a given language? This is apparently the case when different publications dealing with the same science topic (e.g. phenomenon 'C') are compared. Liberty in writing is advisable from an aesthetic point of view, but should it be allowed from a scientific or philosophical point of view?
  • Philippe Le Mercier added an answer in Influenza:
    Could anyone recommend a database for searching influenza mutations in that I can using to BLAST with my own sequences?

    I need a database in that you can search for specific influenza mutations searching in you own sequences, maybe using similar tools like BLAST or something like that.

    Philippe Le Mercier · Swiss Institute of Bioinformatics

    Dear Dr Iván Sanz,

    I would recomand you to use Influenza Research database (IRD), which is the most complete public influenza database.

    On the blast page, the one I linked, you can add in input sequence any data you have either by using a file or just pasting FASTA format.



  • Can we use structural equation modelling (SEM) in an exploratory research?

    Normally, SEM is used to test  some hypotheses. A students of mine wants to use SEM for his exploratory research in the area of Social Media and HR Roles.. He has stated some general and special objectives of this exploratory research, but he does not plan to proceed with making any hypotheses in this connection. Is this OK to use SEM methodology in this type of research?

    Mohammed Nadeem · National University (California)

    Dear Prof Debi:

    Social media being an evolving field, perhaps it may prove very useful especially if the goal is continued innovation!  

    A recent (Alion and Martini, 2013) survey of 500 Italian medium- and high-tech companies (by the Discontinuous Innovation Lab) tested the relations between search practices, exploration activities and firm performance using structural equation modelling.

    The authors argued that the evidence shows that higher levels of search practices lead to higher levels of exploration activities and this, in its turn, can affect firm innovation performance!

    • Aloini, D., & Martini, A. (2013). Exploring the exploratory search for innovation: a structural equation modelling test for practices and performance. International Journal Of Technology Management, 61(1), 23-46.

    Hope this helps!


  • Is there a way to specify how many cores a program should run - in other words, can I control where the threads are mapped?

    Can I run a multi-threaded program and specify how many cores should be used: 1, 2, 4 etc. so as to enable a performance comparison?

    Parallel processing

    Multi-core systems

    Pranav Tendulkar · University of Grenoble

    if you are using pthreads, then you could also use pthread affinity.

  • Albert Magnin added an answer in Viscometers:
    Does anyone work with brookfield viscometer?

    I want to measure viscosity of soy slurry. Is it possible to evaluate viscosity of soy slurry with Brookfield LV 2 PRO? what is the best speed and spindle in brookfield viscometer in this test?

    Albert Magnin · French National Centre for Scientific Research

    Have you identified the range of shear rates involved in your processes : pourability or spray?
    This determines the rheometrical techniques
    Do you observe yield stress or thixotropy on your products?

  • Gert Nolze added an answer in Crystallography:
    How many different angles between lattice planes {hkl} exist?

    Is the number of possible angles between symmetry-equivalent lattice planes {hkl} predictable, or do I have to generate them all and calculate the angles for each pair? I assume it is a property of the metric tensor (and the implemented lattice symmetry).

    Gert Nolze · Bundesanstalt für Materialforschung und -prüfung

    Tetragonal and orthorhombic can be challenging as well because of the arbitrary c/a ratio, but already for cubic would be fine if it could be explainable. For all other the orthogonality doesn't make a big difference (as far as I understand the problem until now).

    For cubic it is a simple questions. nevertheless the solution is not easy to me. The question is easy: h1h2+k1k2+l1l2=const. for two permutations of h2k2l2  where the numbers are the same but have to be exchanged and perhaps multiplied by -1. I only have no clever mathematic describtion for an equation.

  • Bakhtyar K. Aziz added an answer in Platinum:
    Could anyone suggest an organic material which is conducting in dry condition?

    Like electrically conductive AU(gold), Platinum, Silicon.

    Bakhtyar K. Aziz · University of Sulaimani

    poly pyridine?? but i don't know to what extent

  • How can I calculate gene expression levels with RT-PCR?

    I'm studying gene expression level with RT-PCR. Which software can I use?  like REST...

    Laurence Stuart Hall · University of Nottingham

    Hi Dursun

    if you are referring to relative gene expression, i.e increase or decrease of a transcript in treated sample versus untreated (control) sample both normalised to a housekeeping control sample you can perform something called delta delta ct analysis using the ct values for treated test sample; treated control sample; housekeeper (normaliser) treated sample & untreated housekeeper

    This is a standard and published method and will allow you to determine orders of magnitude change (rather than absolute transcript copy number change). If this is what you require this delta delta analysis is very simple to perform in Excel and if you like I can send you an excel worksheet of my own which will take you through the calculations (and into which you could simply copy and paste your own ct values to determine relative expression levels, i.e. use my doc as a template) as well as the original publication method describing the principles

    Regardless, simply google your question and you will get plenty of comparisons answers, including the manual delta delta method

    Let me know if you wish me to provide these documents

  • How can I mix both gases to produce (95%O2 and 5%CO2)?
    We have an isolated tissue bath, panlab 4 channel connected to powerlab (Ad Instruments). We all accessory for tissue bath just we didn't have 95%O2 and 5%CO2.
    Mudhir Sabir Shekha · Salahaddin University - Hawler

    Thanks for all

  • Are there simple protocols to mesure soil texture -plus other significant physical properties?

    What authors/references would you recommend? Are there modifications to Bouyucos for organic rich soils? THANKS!!

  • Annie Klaus asked a question in Pharmacophore:
    A basic explanation of how the pharmacophore keys are generated from 3 point and 4 point Pharmacophores?

    I wanted to know the calculation for generation of pharmacophore keys for 3/4 point pharmacophores. How to make use of interfeature distances.

  • Dr A. Kumar added an answer in HRXRD:
    If we are getting very low intensity in HRXRD of a thin films like 10 or 12 than is it justified with the data?

    If we are getting very low intensity in HRXRD of a thin films like 10 or 12 than is it justified with the data?

    Dr A. Kumar · Harcourt Butler Technological Institute

  • Have you heard a math or math-related joke?

    Heard a math or related joke? Perhaps it has hidden instructive properties? Perhaps not?

    Here is one that is just arithmetic (rounding), but appears scientifically worded. I do not know its origins. It was forwarded to me a few years ago:

    2 + 2 = 5, for very large values of 2.

    Let's hear your favorite joke. It couldn't be worse. :-)   

  • Mohd Zainee Zainal asked a question in QR Codes:
    Is there any way to apply QR code with GIS?

    I am working on a project which requires linking QR code with GIS in order for the system can query the information on certain spatial data.