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  • Which characteristic in Leishmania amazonensis allow this specie to cause post kala azar dermal leishmaniasis and diffuse cutaneous leishmaniasis?

    Is the pathogenesis of these dermal forms always immunologically mediated?

  • How to simulate wsn in ns3, simple example ?

    wireless sensors network

  • Ingo Voigt added an answer in Robust Statistics:
    I am looking to establish a global registry on sonography in hemodynamic assessment; Any interest?

    Dear Potential Participants,

    For nearly a decade, I have been researching the use of bedside sonography in hemodynamic assessment of intravascular volume status (and related topics). Study logistics and getting enough critical mass at a single institution always have been my -- and probably your -- greatest limitation to collecting voluminous enough data for truly robust statistical analyses and comparisons.

    Would there be interest "out there" to participate in an IRB-approved, centralized repository of standardized sonographic hemodynamic data in exchange for full access to collective data and authorship based on pre-defined criteria?

    Examples of data to be collected/entered: IVC dimensions & collapsibility; Other central vein dimensions & collapsibility; Central venous pressures; Pulmonary artery catheter parameters (yes - this "dinosaur" is getting retired, but before it does, let's compare it to something we're going to use for the next 100+ years); Conventional vital signs; Ventilatory parameters (PEEP, Airway Pressures, etc).

    Please let me know... Once a "coalition of the willing" is assembled, we can perhaps change and redefine the way our world views ultrasound in the ICU...



    Ingo Voigt · Elisabeth-Krankenhaus, Essen

    This is a great idea and i would really like to participate as ultrasound guidance is a big issue in our ICU even for hemodynamic measurements.

  • Any suggestions on prioritizing negative over positive in Psychological Constructs?

    I cannot remember the term for a construct that describes our tendency to prioritize negative memories. Evolutionary psychology (I think) says that we risk manage: danger affects our lives more than reward, so we prioritize avoiding negatives and remember them more. Not to crowdsource research, but I seriously cannot remember this or find it.

    Chloe Boyle · University of California, Los Angeles


    Perhaps the "Bad is Stronger Than Good" paper by Baumeister et al. 2001 might help?

  • Ali Alobady asked a question in Data Compression:
    How can use neural networks with data compression?

    how can use neural networks with data compression.

  • Kåre Olaussen added an answer in Mathematica:
    Is there a method based on product and sum principles for counting non-isomorphic trees (acyclic graphs)?

    an example for counting non-isomorphic trees : there exists 6 non-isomorphic trees on 6 vertexes and there exists 11 non-isomorphic trees on 7 vertexes and there exists 23 non-isomorphic trees on 8 vertexes and so on. I find an approach that based on Product and Sum principles for counting non-isomorphic trees. But I don't know that is it approach have polynomial time and is it approach new ... .In my approach, be considered the longest path of tree and do all computations. I writ a program with mathematica software, but long runs out.

    Kåre Olaussen · Norwegian University of Science and Technology

    There are recursive formulas for this, as discussed in https://oeis.org/A000055 (you such read the material you link to). There is also a beautiful efficient algorithm for generating all these trees, in about a fixed time per tree, independent of the number of nodes (but the number of non-isomorphic trees grows very fast with the number of nodes,

    1, 1, 1, 1, 2, 3, 6, 11, 23, 47, 106, 235, 551, 1301, 3159, 7741, 19320, 48629, 123867, 317955, 823065, 2144505, 5623756, 14828074, 39299897, 104636890, 279793450, 751065460, 2023443032, 5469566585, 14830871802, 40330829030, 109972410221, 300628862480, 823779631721, 2262366343746, 6226306037178,

    the total times grows in a non-polynomial way). References below

    """A generator for unlabeled trees.

    Based on the algorithm for generation of unlabeled rooted trees by

    T. Beyer and S.M. Hedetniemi, Constant time generation of rooted
    trees, SIAM Journal on Computing 9, 706-712 (1980),

    and the extensions by

    R.A. Wright, B. Richmond, A. Odlyzko and B.D. McKay, Constant time
    generation of free trees, SIAM Journal of Computing 15, 540-548 (1986).


    You don't mention what you want to do with the numbers; is it a serious problem?

  • Elaheh Hajjarzadeh asked a question in Human Genome:
    what are the risk factors of making a human genome available for study?

    Human genome


    Genomic analysis

    Human genome sequencing

  • Has anyone tried to do 3 dimensional collagen - fibronectin gels?

    I am trying to make 3-D collagen type I gels with fibronectn coating, but fibronectin doesn't seem to bind to the collagen fibers. I have tried preincubating both proteins and incubating fibronectin during and after collagen I polimerization. Any advice?

    Thank you!

    Dr Murugesan Muthu · Imperial College London

    Very simple.

    Try cross-linking with transglutaminase enzyme.  

  • Gerardo Robledo asked a question in Amplification:
    Has anyone had successful PCR, using 5X FIREPOL Master Mix from Solis BioDyne?

    This time I have to use 5X FIREPOL Master Mix from Solis BioDyne (instead GoTaq Green master mix , from PROMEGA) .

    I failed 2 times in my amplifications, even by testing with DNA extracts of which got good amplifications.

    someone has used this Mix?
    What experiences have you?

    Thanks in advance

  • Nikolai I. Kobasko added an answer in Heat Flux:
    Why are critical heat flux densities not widely used when investigating cooling intensities of quenchants?

    The main characteristics of liquid quenchant are critical heat flux densities qcr1 and qcr2. At present, nobody in heat treating industry uses them and doesn't an appropriate standard exist to measure these very important parameters. I'm greatly surprised, why did a such situation appear ?

    Nikolai I. Kobasko · IQ Technologies Inc., Akron, USA and Intensive Technologies Ltd, Kyiv, Ukraine

    As always, thank you very much dear Tarik for interesting discussion. Critical heat flux densities qcr1 and qcr2 are connected with the transition  from nucleate boiling to film boiling and then back from film boiling again to nucleate boiling during quenching process. For transient boiling processes, it is better to  solve Newman problem which can provide very accurate results and makes possibility to use easily critical heat flux densities.

  • Does any have any idea about the clinical applications of Chitosan nanoparticle in drug delivery?

    Dear learned friends, I am looking for the research papers related to the clinical level studies using chitosan nanoparticles for drug delivery in different diseases.So far what ever studies I have come across are either in vitro or only in the model organisms. I will greatly appreciate if any of my intellectual friends from the research gate community could help me with the links to research papers or studies on this topic.

    Thanks in anticipation.

    Rajesh Gupta · The University of Western Ontario

    Thank you so much Dr. Murugesan. I greatly appreciate your kind help.

  • When it comes to simultaneity is Einstein correct or is Dingle correct?

    Albert Einstein claimed in 1905 that a single event can occur simultaneously at different times within two inertial reference frames moving relative to one another. In 1950 Herbert Dingle argued that different times cannot be simultaneous. I have analysed this conflict by deriving the Lorentz equations using both points of view. According to this analysis Dingle must be correct. See youtube presentation of this analysis at  https://youtu.be/4XLYzhHQ64Y

    Valentin Danci · Science

    Stam wrote: "Do the math and you'll find that, if you're consistent, the answer is unique and there's no problem; don't do the math and try to guess the answer and use words , and then you're addressing another question."

    I did the math and I posted the results here twice.
    You didn't say anything then whether there would've been any problem with my math. But the contradiction was clear.

    So it's you who are using convoluted talk to hide the problem. Why don't you do the math and show it here, like I did??

  • Hani Antoun added an answer in Tryptone:
    Cation concentration for phytagel?


    I'm planning to use Phytagel for microbiological purposes, using it with 1:10 Tryptone Soy Broth. I have read that can have some problems by them time of gelling in presence of low concentration of divalent cations. Does anyone know what is the necessary quantity of CaCl2 for the gel to settle?



  • Does Collective Intelligence Exist?

    Simply put: I'm interested in how groups 'think,' 'learn,' 'perform,' and in turn; how this relates back to the individual.

    In particular, I am currently undertaking a Ph.D. on the topic of 'Collective Intelligence' under the supervision of Prof. John Hattie

    I am fascinated by the idea of expanding the typically individualistic notion of 'Intelligence' and 'Intelligence Testing' and applying these psychological subdisciplines to 'groups' of two or more people.

    For example, is there such as thing as a 'Collective Intelligence Factor' that distinctively represents the intelligence of groups (e.g. two or more people) and if so does this 'c-Factor' set the group apart from the intelligence of its individual members?

    In other words: is the Collective Intelligence of groups greater than the sum intelligence of its individual members?

    How can this collective intelligence be measured?

    Does 'group learning' translate to 'group intelligence'?

    Can we use existing psychometric tests (e.g. IQ tests) to measure and predict cognitive differences in groups?

    What makes one group more intelligent than another?

    Do groups made up of highly intelligent members demonstrate higher 'collective intelligence' and outperform groups made up of low or moderate intelligence members?

    If you have any links, papers, conferences, or general thoughts that would help me explore these ideas; i'd love to hear from you.

    Luke Rowe · University of Melbourne

    Fascinating perspective. Thanks Art.

    I think I need more time to process and contemplate your comments before I reply

    (no pun intended). 

  • Abubakkar Sadiq added an answer in ANSYS Workbench:
    How can I find stress on a node/point in ANSYS workbench?

    I am trying to find the stresses on a node on my model. Its a 2D model and consists of two different sized rectangles with the smaller one on top of the bigger one having a contact between them and a force exerted on the top edge of the smaller rectangle and a fixed support at the bottom edge of the big rectangle I am able to find the overall stress but don't know how I can find the stress at a node.

    Abubakkar Sadiq · University of Lincoln

    Thank you very much for your help !

  • What is the cheapest and best candidate for commercialization spray method?

    I want to know in your opinion what is the cheapest spray method, which you may think its the best candidate for being adopted for commercialization in certain branch?

    Robert Anthony Roggers · Independent Researcher

    Perhaps you should be specific about the branch of industry that you are looking at and the potential applications. Thin films, nanoparticles, drug delivery, electronics? Each of these have different types of "spray equipment" used to generate materials with unique properties in response to the needs of the specific industry.

  • Does anyone know how to transform data to normality?
    I tried log transformation, square root transformation, reciprocal transformation and cube root transformation, but these methods did not work. Do you have any suggestions?
    Remilien Emmanuel · Colegio de Postgraduados

    I¨m fully agree with Emilio. You must try to find non parametric equivalent test of the parametric you have in mind

    Check out this paper.... REGARDS

  • Does anyone have a new article on ameloblastomas ?

    I need a new article ( review article ) on ameloblastomas .

  • Any Germany based researcher interested to apply for the bilateral Sweden-Germany collaboration grant, to strengthen research in materials science?

    Framework Grant Röntgen-Ångström Cluster

    The Röntgen-Ångström Cluster (RÅC) is a Swedish-German research collaboration within structural biology and material sciences. The aim of the grant is to strengthen research in materials science and structural biology that uses neutron and/or synchrotron radiation and to stimulate the use and/or development of expertise in large-scale research infrastructures currently available or being planned in the area.

    The Swedish Research Councils’ framework grant aims to give researchers the opportunity to do research with significant scope and depth. Framework grants can give strong research groups the freedom to act within relatively generous frameworks regarding funding and choice of research orientation. The Swedish Research Council supports basic research of high quality in all scientific disciplines and promotes research cooperation and exchanges of experiences.

    More information can be found here:


    If interested, please contact me by sheng.guo at chalmers.se. Note the deadline for application is 2015-06-03

    Sheng Guo · Chalmers University of Technology

    Please follow the link given to find more information.

  • Omar Mohammed asked a question in Mesh:
    I am working on meshing Aorta stl file by CT scan i don't know how to extract sharp features to fit blocking into geometry any help/recommendations?

    ICEM Meshing , Aortic Arch biomedical 

  • Is it routine in your intensive care unit to perform ultrasound-guided central venous catheterization?

    Is it routine in your intensive care unit to perform ultrasound-guided central venous catheterization?

    Ingo Voigt · Elisabeth-Krankenhaus, Essen

    I encourage all my residents to use US for venous and sometimes arterial punctures. Why ? We have a US machine so why not use it ?  Procedure times go down even in emergencies, Patients with long ICU stay often show jugular vein thrombosis, so its better to see it before puncture. The only arguments against a routinely usage of ultrasound is the absence of an ultrasound device or the fact you never tried it before. After 2-3 supervised procedures residents can safely use it.

  • What age correction is needed for mollusc C-14 dates from Black and Marmara Sea lacustrine phases?

    High resolution dating of events in the Black and Marmara Seas during non-marine phases requires appropriate correction of C-14 ages because shells are not in equilibrium with global values of ca. 400 yr. Proposed values range from 0 (fully mixed, in equilibrium with atmosphere, no correction needed) to 1000 yrs (benthos contain old bottom water or river transported carbon). Peat (grows in equilbrium with atmosphere) compared to in-situ shell from the same sample   indicates a reservoir correction of ca. 850 yrs is needed for shells. Which correction value is correct for A) Black Sea? B) Marmara Sea with overflow water.

    May be less old carbon is remove from the watershed during low soil erosional phase ??

  • Wei Chen added an answer in Association Rules:
    Is there a free higher educational dataset for use in a data mining project?

    We want to discover association rules among the student score data in order for instance to uncover the link between scores within a same teaching unit of bachelor studies or master's studies, or between different teaching units. The association rule mining should also allow us to explain the good or bad performance of students with regards to their choices of study fields/specialties. The data set need not reveal the real names of students who can be anonymous; however, each student should be identified by a unique ID along the years of his/her studies.

  • Is it possible to estimate the uncertainty for values of crystallite size and strain calculated from a williamson-hall plot, using error in grad. & c?

    Is it possible to estimate the uncertainty for values of crystallite size and strain calculated from a williamson-hall plot, simply by using uncertainties of the linear fit gradient and y-intercept (obtained from LINEST function in excel) ? and then propagating the error as size = K. wavelength / y-intercept etc

    Also simple question: what is usually the uncertainty in wavelength used in x-ray diffractometer, if there is one? I have used Cu K-alpha radiation

    Thanks for any help

  • Any one know how to solve this problem similar to Dimensionality Reduction?

    Hi, does any one know any methods for solving this problem? 

    Input: features vector x (N-dimensional vector), 

    Output: results y (scalar)

    We know that y is a function (may be not linear) of some components of x (e.g., depends only on K elements of x) ;

    We have some samples of x and y; How can we find which K components that y depends on?

    I think this is similar to the dimensionality reduction in Machine Learning, but different because: what we want is which component will affect the value of y; the components of x may not be correlated; all components of x may be dependent, but some of them can be discarded because it does not affect the value of y.

    Could some one give me some suggestions or references? Thanks! 

  • Wilton Filho added an answer in Indian Ocean:
    Can anyone share website with the Indian Ocean Index (IOD) for over 2013 ?

    We need to study more about dynamics of water temperature due to climate change and its effect on marine organisms in Indian Ocean 

    Wilton Filho · Fundação Universidade Federal do Rio Grande (FURG)


    You can download the time series here:


    Other indexes are also available on NOAA website:


  • Aswin K Garimalla added an answer in EDC:
    How do I improve the yield of a carboxylic acid/amine coupling with EDC/DMAP at RT in DCM?

    The reaction of the carboxylic acid and EDC alone gives three spots on a TLC. Are the three spots due to N-O displacement?

    What can I do to produce one spot only?

    I have thought of carrying out the reaction at lower temperatures.

    Aswin K Garimalla · Argonne National Laboratory

    Check this thread too. 


  • Phil Lucht added an answer in ResearchGate:
    Uploading publication in PDF format?
    Any idea anyone why I cannot upload a publication in pdf format? Uploading stops at a certain % (can be 56 or 99) and then it freezes. Any help is appreciated.
    Phil Lucht · Rimrock Digital Technology

    I have two very similar scanned PDF files. One (the larger at 7 MB) uploaded fine, the other (6.5 MB) had the problem stated by G. Braathen -- successful 100% upload then hang, cannot activate the Continue button. Same problem from Firefox 36.0.4 or IE11. Tried as a manual upload, and the upload completes and then things hang while the running  two-disk animation says "Analyzing".  I think something in my PDF file is causing an infinite loop in the Researchgate file upload analyzer software. Two hours wait does not help (Firefox, "other" research material upload). Both PDF files display just fine in Acrobat Reader XI and other PDF viewers. Frustrating!  I put in a RG help request yesterday, but with 6 million users it is hard to imagine them having time to fix this.

  • Does anyone have experience with visualizing stress granules in primary neurons?
    I would like to visualize stress granules in mouse primary neurons with immunofluorescence. I am concerned because I heard this works best in HeLa or COS cells, which have a large cytoplasm. What do you think? Under which conditions are stress granules induced in primary cells?
    Anais Aulas · Harvard University

    I already work with primary cortical neurones and stress granule. The labelling was quite easy; I used FISH (olidodt probes) to visualize SG. Pictures looked really great. In addition I also stained for some other protein without any trouble.