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  • What is the incidence of complicated cholecystitis?

    What is the incidence of complicated cholecystitis, such as with fisula or perforation

    Abdullah Muhayl Alotaibi · National Guard Health Affairs

    Thank you very Dr. Jane C. Holland

  • Thomas Korimort added an answer in Formal Languages:
    How algebra structure increases the power of formal grammar?

    How different type of algebra structure like lattice, integral lattice monoid and other algebra structures increase the power of formal language.

    Thomas Korimort · Not affiliated

    Dear Ajay, if you plan to make a language parser or speech recognition util, then i will only suggest in one sentence to start from the problem itself and not trying to apply too much tight mathematical models. Design your own models!

  • Barbara Sawicka added an answer in Cement:
    Are there any cheaper, more easily available, affordabe, viable alternatives to cement in the building industry?

    The building industry over-depends on cement as a matrix in the building construction industry. Consequently, cement has become an expensive macro parameter that keeps an escalating and oscillating stranglehold on the building construction industry. Are there any other viable alternatives to break the monopoly imposed by cement?

    Barbara Sawicka · University of Life Sciences in Lublin

    I agree with Wojciech and Ryszard

  • Reshi Nawab added an answer in Software:
    Exist some kind of freeware program I can use to categorize type of words and apply a stemming process?

    Hi, I'm a PhD fellow in Information Science and I'm trying to create a domain ontology by using some previous text. At this moment I'd like to use a freeware program to categorize words into nouns, verbs, adjectives, conjunctions, etc. and after that apply a stemming process in order to reduce the human revision.

    My problem is that I don't know how to use algorithms or complex software because I always worked searching for information but not creating tools, so I need something very simple and intuitive software

    Can anybody help me, please?

    Reshi Nawab · King Saud University

    Yes , Juan , I tries it once its kind of good !! 

    Maria You can give it a try .

  • Are there any websites/software related to the developing of teaching materials for autistic children?

    i want to develop innovative teaching material for autistic children so i want to know about websites developing these material.

    Carl Alexander Sorensen · University of South Carolina

    My colleague Allison Randell at the University of South Carolina found a graphic design service to make some really exceptional visual supports. I believe the service was very reasonably priced as well. Allison is a post-doc for Michael Beets in exercise science/public health if you want to look her up! She is also listed as a collaborator on my page.

  • Rodrigo Sychocki da Silva asked a question in Piaget:
    How does information technology influence on the process of "restructuring" of cognitive structures, in view of Genetic Epistemology of Piaget?

    Starting from the hypothesis: the modification of the structures, the improvement of assimilatory schemes, make the best subject in the study on a given problem situation. Wonders about the impact of computer technology in the process of modification and cognitive reconstruction of the subject.

  • Thomas Korimort added an answer in Metaphysics:
    Is it meaningful to work out on old Aristotelian (metaphysical) models of science in order to get insight into modern research topics?

    It is known that our modern sciences are built on the Aristotelian system of philosophy. Even earlier than that it is known, that greek culture had a complete and sound system of scientific disciplines. Regarding our chaotic states at todays university departments, wouldn't it be nice to return to the roots of all true science? In such case, would it be again possible to educate geniuses knowledgable in all the scientific disciplines? How to integrate new knowledge and scientific disciplines that did not exist at that time? Is king Salomons saying true, that everything returns and everything that is was already there before?

    Thomas Korimort · Not affiliated

    @Lucas: I adopt the Platonic as well as the Aristotelian terms just because they seem to be more popular among scientists and also more accepted than let us say the corresponding religious system also proposed by Neoplatonism. As for Aristotle i think that the cause-effect relation you mention is a well-known viewpoint in biblical and related mystical system, but who cares? Aristotle's Nicomachean ethics contains maybe thoughts that also arise in the systems of gods in polytheistic religions like the triad Brahma-Vishnu-Shiva, which is maybe the Hindu counterpart to the ethics of Aristotle. So this would be one way to connect our western thinking to eastern religions and rediscover their wisdom and philosophy in our own traditions.

  • Leroy Mason added an answer in Pearl:
    Can you help me clarify definition 16 of Bochman and Lifschitz(2015)?

    In [1], Definition 16 has an expression I am having trouble parsing. See the attachment.

    If it is not a mistake what does the (in latex) $_{\triangle|l$ mean?

    [1] A. Bochman and V. Lifschitz, “Pearl ’ s Causality In a Logical Setting,” 2015.

    Leroy Mason · University of New South Wales

    Thanks for the reference!

  • Lloyd C. Irland added an answer in REDD+:
    Why has the mechanism of REDD+ become so much popular at present considering that it was rejected during the Kyoto Protocol era?

    Why has REDD+ (formerly known as Avoided Deforestation) come to occupy such a central position in climate change discourses recently. What has changed since it was first rejected in the KP/CDM era? Has those reasons cited for its rejection been addressed now? What is REDD+ really supposed to deliver. 

    Lloyd C. Irland · University of Maine

    HI,  Seems to me that REDD does not take control of forests --  that was done by the colonialists and then the successor governments.  The indigenous people do not control those territories, with minimal exceptions, today, and will not until their own governments make it happen.  

    This will not be easy, if only because the local people do not always agree with each other on all the issues.

    However that may be, meetings in Copenhagen, Cancun, or whrever cannot give indigenous people meaningful control over their forests -- or take such control away from them, either.


  • Thierry Beths added an answer in Anaesthesiology:
    Does anyone have a good reference describing in detail the steps of TAP blocks?

    I am working on modifying TAP block in animal and am working on detailed steps of the block in human. Unfortunately, the few references I looked in are not really helpful?

    Thank you


    Thierry Beths · University of Melbourne

    Hi Paulo,

    Thats great thank you...I got the papers. You are right, I should contact her for more information. 



  • David L Morgan added an answer in Multicollinearity:
    Do wrongly designed questionnaire contribute to multicollinearity problem?

    It is told that in the questionnaire design, if the similar types of items (IV and DV) are placed side be side will contribute to multicollinearity problem in statistical analysis. Need advice. 

    David L Morgan · Portland State University

    Multicollinearity is a problem that occurs when you have a high level of correlation among your independent variables. It does not refer to the correlation between your IV and DV.

  • Masood Ejaz asked a question in Menthol:
    Toxicity and repellent effects of eugenol, thymol, linalool, menthol and other pure compounds on Dinoderus bifloveatus (Coleoptera: Bostrichidae)?

    Please I need this paper

    '''Toxicity and repellent effects of eugenol, thymol, linalool, menthol and other pure compounds on Dinoderus bifloveatus (Coleoptera: Bostrichidae)'''...'

  • António Calha added an answer in Competences:
    What are the primary competencies that principals or head teachers should have?

    I am working on developing competency standards for principals and head teachers. I hope you can help me identify the primary competencies of school heads.

    António Calha · Instituto Politécnico de Portalegre

    Here you find a full set of competencies (text in portuguese):


  • Felipe De Souza Leite added an answer in Myofibrils:
    How do I optimize myofibril isolation from skeletal and cardiac muscle cells?

    I often isolate myofibrils using a homogenization protocol, but it is very common to get bundles of myofibrils (specially from cardiac cells). I wonder why and how I could optimize this isolation so it yields higher amounts of single myofibrils. Maybe any enzyme treatment... 

    Felipe De Souza Leite · McGill University

    Ok. We have triton here. We use it more with cardiac samples. I'll try your ideas and let you know later. Thanks for the discussion Marco!

  • Which re-seq method in NGS will be better ?

    for the same sample,

    1     seq it at 300× depth , using one single liaberary.

    2     seq it 5 times, each time using different liaberarie. totlly 100× depth.

    Fritz J Sedlazeck · Cold Spring Harbor Laboratory

    I would suggest you try the second. This way you can eliminated errors introduced by PCR or whatever. It will give you statistically a better signal since you observed things 5 times "independently" from each other. However, I would not waste my money to sequence to this high coverage.... 

  • If rat antibody is injected into a mouse, how mouse will the mouse respond? Will the antibody still function?

    i want to make rat monoclonal antibody which will be used in mouse. But how  rat antibody is homologous with mouse antibody?Can rat antibody function well in mouse?

    Elena Yu. Filinova · Advanced Biomedical Research Laboratory, RF; Vidipharm Gmbh, Austria

    Yes, mice also survive 10 times higher doses of cytostatics treatment than people do. It is possible to obtain Fc-species-specific antibodies in mice, rat-, rabbit-, guinea pig- human- and others. Mice are not happy about foreing antibodies, or serum, or tumor inoculation, but as they survive the treatment they are most common laboratory animals. Chronic toxicity of novel pharmaceuticals are run in rats and dogs, mice are too well-tolerating for these pre-clinical investigations. It is also true that 90 percent of acute tocicity pre-clinical trials are run in USA now because there are not many laboratory animals facilities left in Europe. Most were forbidden to work and were closed due to Green parties activity. 

  • Edmund Pool added an answer in Drugs:
    How to check for immune modulation?

    When a new drug is administered for its possible immune modulatory effect, how do we check the status of the immune system or the efficacy of the drug apart from the clinical signs.

    Edmund Pool · University of the Western Cape

    Can you take 1 ml blood aliquots from your subjects? over what time frame would the drug be administered.  To check if acquired immunity is modulated use blood collected in heparinised vacuum tubes. Do the following under aseptic conditions:

    Add 40 ul blood to 360 ul RPMI1640 culture medium (control)

    Add 40 ul blood to 360 ul RPMI1640 containing 16 ug/ml phytohemagglutinin (stimulated sample).

    Prepare each in triplicate.  Incubate overnight at 37 C in a 5 % CO2 incubator.

    Collect the supernatants and screen for IFNg (cell mediated immunity) and IL10 (humoral immunity). This can be done using an ELISA or FACS. Most hospital pathology labs would assay these cytokines regularly.

    Cytokine levels should be compared for blood taken before drug therapy and after drug therapy. Changes in these cytokine levels will tell you if the drug affects these two pathways.

    The same can be done for inflammatory activity.  We use 1 ug/ml LPS as stimulant and IL6 as biomarker for this pathway.

    There are several other markers that can also be used for these pathways.  I have just given you the once that we used previously for checking immune status.

  • How can I calculate df (degrees of freedom) for F values in the two-way repeated measure ANOVA results?

    I have done two-way repeated measure ANOVA for my thesis data but I could not understand how F and P values can be calculated with df (degrees of freedom). I need help.. Thanks.

    Goran Qader Othman · Hawler Polytechnic University

    Really, the question is not very clear, because if you have blocks as another factor or direction, then you have to use factorial RCBD and the block df should be added to the calculation of F value, but if you just have two factors without any other directions or internal factor, you 'll use Factorial CRD without having df for blocks.

  • Tayyiba Mushtaq asked a question in Regulation:
    Can anyone recommend good material on Relational Regulation Theory?

    Relational Regulation Theory

  • What are the necessary procedures to check the outputs of education, learning accounting?

    It is known that there are many of the expected outputs of accounting education program, including for example:
    Knowledge, practical skills, social skills, and other
    This requires the existence of a mechanism which is to make sure these requirements are met.

  • Brian Scott Comer added an answer in Co-Culture:
    Does anybody have experience with Endothelial cell and Aortic smooth muscle cell co-culture?


    I am interested in performing co-culture in 100 mm dish with transwells (75 mm) with endothelial cells and AoSMC. any advice how to perform it. after the treatment i would like also to scrape the cells in the bottom of the petri and onto the transwell membrane for collecting protein; especially for the second case. is possible? also what do you suggest? putting EC on the transwell and SMC on the petri dish or the contrary.

    thank you in advance

    Brian Scott Comer · Indiana University-Purdue University Indianapolis

    Check out this paper.  Different type of vascular smooth muscle cells but the method should work for you as well.

    Am J Physiol Lung Cell Mol Physiol. 2011 Oct;301(4):L527-35. doi: 10.1152/ajplung.00091.2011. Epub 2011 Jul 29.
    Myoendothelial gap junctional signaling induces differentiation of pulmonary arterial smooth muscle cells.
    Gairhe S1, Bauer NN, Gebb SA, McMurtry IF.
    Author information
    Myoendothelial gap junctions are involved in regulating systemic arterial smooth muscle cell phenotype and function, but their role in the regulation of pulmonary arterial smooth muscle cell (PASMC) phenotype is unknown. We therefore investigated in cocultured pulmonary arterial endothelial cells (PAECs) and PASMCs whether myoendothelial gap junctional signaling played a role in PAEC-dependent regulation of PASMC phenotype. Rat PAECs and PASMCs were cocultured on opposite sides of a porous Transwell membrane that permitted formation of heterotypic cell-cell contacts. Immunostaining showed expression of the gap junctional protein connexin 43 (Cx43) on projections extending into the membrane from both cell types. Dye transfer exhibited functional gap junctional communication from PAECs to PASMCs. PASMCs cocultured with PAECs had a more contractile-like phenotype (spindle shape and increased expression of the contractile proteins myosin heavy chain, H1-calponin, and α-smooth muscle cell-actin) than PASMCs cocultured with PASMCs or cocultured without direct contact with PAECs. Transforming growth factor (TGF)-β1 signaling was activated in PASMCs cocultured with PAECs, and the PASMC differentiation was inhibited by TGF-β type I receptor blockade. Inhibition of gap junctional communication pharmacologically or by knock down of Cx43 in PAECs blocked TGF-β signaling and PASMC differentiation. These results implicate myoendothelial gap junctions as a gateway for PAEC-derived signals required for maintaining TGF-β-dependent PASMC differentiation. This study identifies an alternative pathway to paracrine signaling to convey regulatory signals from PAECs to PASMCs and raises the possibility that dysregulation of this direct interaction is involved in the pathogenesis of hypertensive pulmonary vascular remodeling.

  • Sheryhan Farghaly added an answer in Nanotechnology:
    Why after diluting the chitosan coated organic lipid nanoparticle had the suspension zeta potential of the particles incresed for my nanosuspension?
    I have serially diluted the cationic chitosan nanoparticle solution and i found that the zeta potential in millivolts is increasing ? I could not understand this phenomenon on the basis of scientific principle
    Sheryhan Farghaly · University of Cincinnati

    hi, lokesh, Do you understand this phenomena. because i have the same problem when i try to coat the chitosan with lipid. so if you reach to a solution please till me

  • Sandeep Kaur added an answer in Ethylene Oxide:
    Does anyone know of a non-ionic polyethoxylated surfactant with 15 to 20 ethylene oxide units?

    Other than polysorbate 80?

    Sandeep Kaur · Simon Fraser University

    Thanks Pallas for this great idea. I will contact. 

  • Yevhenii Rohozin added an answer in Pollen:
    What technique do you prefer to make permanent modern pollen slides?

    We treat specimens (anthers) with 10% KOH and then mount them in glycerol, but there are some articles where authors say that glycerol gradually destroys pollen grains. What do you think?

    Yevhenii Rohozin · National Taras Shevchenko University of Kyiv

    Lydie, Gonzalo and Mark, thank you for your valuable answers.

    Best wishes.

  • Bernhard van Vondel added an answer in Coleoptera:
    Does anyone want to collaborate with me with the identification of aquatic coleopters?

    I am looking for collaborators for post doct studies.

    Bernhard van Vondel · Natuurhistorisch Museum - Rotterdam

    dear Dr. Aykut,

    If you have problems with the identification of Haliplidae I can probably help you.

  • Hitesh Changela asked a question in Organic Polymer:
    What types of organic polymers made or found on Earth have affinities to those found in insoluble organic residues from carbonaceous meteorites?

    Insoluble organic matter residues are the remaining insoluble organic material after extreme acid digestion of the extraterrestrial material. They contain complex morphologies that exist as either: isolated spherical compounded shapes; hollow spherical objects or irregular (non spherical) shapes which internally often contain the same conglomeration of spherical features. Please see attached DF STEM images of some of these morphologies from two organic rich carbonaceous chondrites. As the residues are a product of the removal of surrounding mineralogy (i.e. context in situ is lost), connected features on the submicron to micron scale in the images, by approximation, should only be considered. Thanks!   

  • Hossein Zarezadeh asked a question in Min6 Cell Line:
    Where can I purchase/borrow MIN6 Cell line in the US?

    I need MIN6 cell line to do some assays on insulin secretion.

    Any clue may help.

  • Paul C. Lyons added an answer in Volcanology:
    What is the source of heat in oceanic plate hotspots?

    We know of a number of hotspots on oceanic plates, but do we know what causes them?

    Paul C. Lyons · United States Geological Survey

    Hi John, Thanks very much for your answer. It is nice to know of  a different kind of hot spot.

  • Alejandro Martin added an answer in Western Blot:
    Any suggestions on why in Western blotting I can not get the bands of Lrp1?

    Western blotting :In first i could get the lrp1 both bands but now its very difficult to get the bands. instead i get non specific bands .for cross check i have done the western blotting of old sample also i got the result. i know that i have some problem in my cell lysate preparation. What could be the mistake?

    Alejandro Martin · Center for Genetic Engineering and Biotechnology

    You need a positive control (maybe you have one, but it is not obvious from your description). Do you have one and if so, what is it?

  • Are there informal ways/tools to encourage the self-reflection of teachers/lecturers on the way they give feedback to their students?

    In our curriculum the student needs to critically reflect on his own learning. But are the teachers capable of giving proper feedback in order to allow the student to grow in this competence? Are the teachers themselves capable of critical self-reflection? And if not, how can this be encouraged or triggered in a non-offensive way?

    Marysol Bouwens-Verloop · Hogeschool Utrecht

    Lorraine, thank you for your bright explanation. This seems a nice way to self assess ones own practice, although maybe your audience will be different than mine, for I 'll have to 'seduce' (what is the right word?) my collegues into self-evaluation.. I am currently brainstorming and this one I will put on my list as an option to use as an example for a 'lesson' or workshop on 'how to give and receive feedback'...