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  • Can anyone suggest how to find the transition state with different functional?

    I have a problem to find transition state with PBE functional. I have already used the scan process and use the opt=(ts,calcfc,noeigentest) and redundant option 4 5 D to optimize the transition state. But I can't find any imaginary frequency. Then I tried use qst3 calculation to find the transition state, but I found the transition state with BLYP functional. Is there any way to find out the transition state or some suggestion to do this calculation?

    Yazid Meftah · Université de Biskra

    hello;

    but the problem persist with PBE

  • Rod Sutcliffe asked a question in Design Thinking:
    What design activities facilitate creative architectural concept development? Can these activities be systematized into a simple design methodology?

    The question (obviously) is in two parts:

    Firstly, drawing on the theories around design thinking, in particular within the logical reasoning framework (deduction, induction, abduction) expounded by Nigel Cross, Kees Dorst and N.F.M. Roozenburg), what activities would be carried out by a designer which facilitate creative design and problem solving? What actions and graphic tools (mapping, sketching, diagramming and modelling) would this entail?

    Secondly, can these activities be organised in such a way to formulate a method which can be applied in multiple design situations?

  • Vladimir Farber asked a question in Liquid Crystals:
    I have trouble finding certain parameters of the liquid crystal E44.Can somebody help me with this?

    What is the value of the rotational viscousity of (Merck) E44 Liquid Crystal? How E44 depends on the voltage? I need to know these parameters for the experiment. Thank you in advance!

  • Neeraj Tewari added an answer in Spectroscopy:
    Can anyone introduce software for numerical spectroscopy(for example UV-vis)?

    I want simulate different spectroscopy, and don't know anything about numerical spectroscopy

    please help me

    thanks

    Neeraj Tewari · Chaudhary Charan Singh University

    DFT and TDDFT calculations may be invoked with the help of Gaussian conveniently.

    arrett-group.mcgill.ca/tutorials/Gaussian%20tutorial.pdf

    www.gaussian.com

  • Ravi Kumar Chanana added an answer in Devices:
    How is the work function of heavily doped poly-silicon carbide affected by temperature?

    doped poly-silicon carbide may be needed as gate contact for SiC devices.

    Ravi Kumar Chanana · Galgotias College of Engineering and Technology (GCET)

    Prof.Lawrence Margulies:  I would like you to comment on the attached article that gives an experimental account of decrease in WF of Ag by 0.2 eV due to a rise in temperature of 480oC.  Others may also comment.

  • Nik Da asked a question in Adherent Cells:
    What is the best system do measure migration of adherent cells e.g. Macrophages?

    What system is the best to use and how can you measure the outcome?

  • Abdelkader BOUAZIZ added an answer in PET:
    What additives can be used to increase the glass transition temperature (Tg) of Isosorbide based PET PET?

    The end-cap additives used here in this process should not effect other properties such as color, crystallanity etc.

    Abdelkader BOUAZIZ · Univ. Ibn Khaldoun Tiaret

    Dear all,

    it is almost impossible to add an additive to a polymer matrix without affecting to some extent its intrisic properties (positively or negatively). However, a partial curing (photo-curing) to a certain level will allow you to much the desired increase of the Tg. Regards

  • Yuanzhang Li added an answer in Cross Tabulations:
    How (with which measure) can I report about the strength of the association of a 2x5 cross tabulation if I have expected values smaller than 5?

    Hello, i'm reporting a cross-tabulation (of 2x5 sizes) at SPSS. There are expected values less than 5 in the cells, so i'm using Fisher's exact test instead of chi-square (i learned this from researchgate.net). Afterwards, i want to also report about the strength (correlation) of the association. If i'm not mistaken, i know that normally i can use "Cramer's V". But provided that i have expected values smaller than 5, can i still report the strength of the association by still using "Cramer's V"? And if i can't, how (with which measure) must i report about the strength of the association in this condition?

    Yuanzhang Li · Walter Reed Army Institute of Research

    The overall Chi-square with df=(2-1)*(5-1)=4 just tell you if two factors are independent or the distribution of one factor is homogenuous across other factor.

  • Parna Gupta added an answer in Metal Complexes:
    How can I make a single crystal of a metal complex?

    My metal complex only dissolve in DMSO & DMF. how can i make single crystal .Please let me know if you have any suggestions.

    Parna Gupta · Indian Institute of Science Education and Research Kolkata

    For the complexes soluble only in DMSO and DMF, the simple process works well: dissolve the compound in the solvent and spread the DMSO/DMF solution in a Petri dish and keep it in the air. To avoid any contamination a butter paper can be kept on the Petri dish. Be patient!

  • Jayson Enciso added an answer in Marine Algae:
    Can you help me identify the scientific name of this marine algae?

    This species was collected in Romblon, Philippines.

    Jayson Enciso · Romblon State University

    It is not a sargassum polyphyllum.

  • Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Alfredo Pereira Junior · São Paulo State University

    Dear All, please read this well written article (link below) with an informal history of the Hard Problem

  • Is wide excision needed for low rectal cancer after preoperative CCRT with complete response?

    oncology surgery, radiotherapy physicians

    Frédéric Dumont · Institut de Cancérologie Gustave Roussy

    The response of Dr Julianov is very interesting and assessed in France in a randomized study. But some data are missing to be sure. If the histopathologic examn doesn't confirm the ypT0N0, the radical surgery after the local excision specially in the low rectum is more difficult and the fistula risk is certainly increased. If these fistula are too important with their consequences (poor functional result; distant recurrence), the organ preserving strategy could be questionned.

  • Jorge Parodi added an answer in Electrodes:
    Why is fEPSP depressed upon induction of LTP?

    There is an issue that I would like to seek the help of the scientific community regarding. My experiments involve tetanization of hippocampal CA1 to induce long term potentiation (LTP). However, after delivery of a series of tetanic pulses at 100 Hz for 1 second, the signal from the slices get depressed immediately (i.e. the slope of fEPSP becomes close to 0). Occasionally, they return after some time, but the recordings are not usable.

    I have been told that this is due to faulty electrodes, but even the use of new electrodes also do not seem to circumvent the problem.

    Regarding the protocol that I use, after dissection of hippocampal slices, they are left to incubate in aCSF (perfused with carbogen) for 2 hours before taking the Input/Output (I/O). 15 minutes after taking the I/O, recording starts and tetanization is only introduced after slices have achieved a stable baseline for 30 minutes.

    I am using Intracell (Germany) and my electrodes are from A-M Systems (Stimulating Electrodes, Substrate Stainless Steel, Diameter 0.010 in., Tip Exposure 1 mm). The electrodes have had their tips slightly cut as based on my own experience, overly sharp electrodes do not give good signal and lead to immediate depression of fEPSP upon LTP induction.

    I sometimes also observe condensation of droplets on my electrodes and when I remove them, they sometimes affect my recordings. Hence any explanation and advice on this issue would be greatly appreciated!

    Jorge Parodi · Temuco Catholic University

    Hi man, I see you problema, but maybe you must  put atention of you protocol of tetanus, remeber the LTP and LTD used similar stept and some time you can see a "cross talk"

    change your stimul, maybe you have good slice and exelent condition and not need a stronger tetanus. Another point is the solution, maybe you can check the concentration of PTX.

    And finally for my, maybe you are in forn and need discovery and try to modulate, some time the errors are more important!

    cheers

  • What studies have been done to evaluate the effectiveness of air showers in controling particulate matter and/or lead contamination?

    Air showers (a.k.a. air tunnels, air curtains, air booths) are used in "clean room" design to control the particulate (dust) introduction into the clean room operations. In addition, air showers have been employed to reduce lead contamination of garments at other facilities such as secondary lead smelters and indoor firing ranges. I am looking for any studies/research into their effectiveness or design evaluation. Please advise. Thank you.

    Shaban Ahmed Ali Abdel-Raheem · Assiut University

    You are wellcome Andrey Tsepelev 

  • Can anyone express the mathematical equation for love?
    Although many believe love is a subjective expression, is there an objective mathematical function for it?
    Anup Kumar Bandyopadhyay · Jadavpur University

    Love being a highly complex and nonlinear process it needs a precise and thorough understanding before a suitable model can be prescribed. The model is expected to be unique for each particular instance. Thorough understanding requires intimate involvement in the actual system which in turn would result intellectual limitations.

  • Paolo Piazzetta added an answer in NAMD:
    Why do I get this error while running psfgen for NAMD?

    I want to run dsDNA-protein MD simulations.

    I have tried to use top_all36_na.rtf I
    prepared a script to run psfgen:

    package require psfgen
    resetpsf

    topology charmm36.nbfix/top_all36_na.rtf
    topology charmm36.nbfix/top_all36_prot.rtf
    topology charmm36.nbfix/top_water_ions.rtf

    mol new prot-DNA.pdb

    set sel [atomselect top protein]
    set chains [lsort -unique [$sel get chain]] ;# return A

    foreach chain $chains {
    puts "Adding protein chain $chain to psfgen"
    set seg ${chain}PRO
    set sel [atomselect top "protein and chain $chain"]
    $sel set segid $seg
    $sel writepdb tmp.pdb

    segment $seg { pdb tmp.pdb }
    coordpdb tmp.pdb
    }
    set sel [atomselect top nucleic]
    set chains [lsort -unique [$sel get chain]] ;# return A B C D
    foreach chain $chains {
    puts "Adding DNA chain $chain to psfgen"
    set seg ${chain}DNA
    set sel [atomselect top "nucleic and chain $chain"]
    $sel set segid $seg
    $sel writepdb tmp.pdb

    segment $seg { pdb tmp.pdb }

    set resids [lsort -unique [$sel get resid]]
    foreach r $resids {
    patch DEOX $seg:$r
    }
    regenerate angles dihedrals

    coordpdb tmp.pdb
    }
    guesscoord

    after that I am getting:

    Adding DNA chain B to psfgen
    psfgen) building segment BDNA
    psfgen) reading residues from pdb file tmp.pdb
    psfgen) extracted 46 residues from pdb file
    psfgen) Info: generating structure...psfgen) Info: skipping conformation
    O3'-O5'-P-O2P at beginning of segment.
    psfgen) Info: skipping conformation O3'-O5'-P-O1P at beginning of segment.
    psfgen) Info: skipping conformation O3'-P-O5'-C5' at beginning of segment.
    psfgen) Info: skipping bond O3'-P at end of segment.
    psfgen) Info: skipping conformation C3'-O3'-P-O5' at end of segment.
    psfgen) Info: skipping conformation C4'-C3'-O3'-P at end of segment.
    segment complete.
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) applying patch DEOX to 1 residues
    psfgen) regenerating all angles
    psfgen) regenerating all dihedrals
    psfgen) reading coordinates from pdb file tmp.pdb
    psfgen) Warning: failed to set coordinate for atom C7 THY:288 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:291 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:292 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:298 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:299 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:310 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:316 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:321 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:323 BDNA
    psfgen) Warning: failed to set coordinate for atom C7 THY:330 BDNA

    What did go wrong?

    Could someone please let me know what sort of mistake I've probably made
    here?

    Paolo Piazzetta · Università della Calabria

    Dear Urszula, if you look in the top_all36_na.rtf at the line called RESI THY you can see that there is no C7 atom. So you have to understand if C7 (this is the name in the PDB) needs to be renamed to find a correspondece in the top_36 file or, if it is not explicit present, you must insert manually the missing parameters.
    We are talking about CHARMM FF.
    Another option is to use AMBER and through AmberTools suite you can build your parameters file using Xleap or Tleap. At this point you can run your MD with NAMD with the AMBER keywords:
    http://www.ks.uiuc.edu/Research/namd/2.9/ug/node13.html

    I hope I was clear

  • Tang Suye added an answer in Thermodynamics:
    Why the equation of the first law contains a negative definite function?

    For the first law

    dU=TdS-pdV+ΣμdN.

    According to the physical meaning of the internal energy, U represents the total energy within the system, so should be expressed as the sum of the different types of energy within the system, whereas, if we consider an integral equation, for Euler equation

    U=TS-pV+ΣμN.

    Since p and V are the two positive definite variables, so –pV is a negative definite function. Therefore that, the mathematical form of Euler equation conflict with the physical meaning of the internal energy.

    For instance, for a photon gas, the integral of –pdV is less than zero. Helmholtz free energy

    F=-pV=-U/3.

    Where F is a negative definite function, so F cannot be explained as a part of the internal energy, then what it is?

    I have my own answer for this question, but want to know what your opinion is.

    Tang Suye · Independent Researcher

    Dear John,

    I modified my article, this is the new version.

    Best regards,

    Tang

  • Anyone familiar with the reinforcement of a concrete beam?

    When the reinforcement is in to the concrete everything is ok. But I need some part of reinforcement to be out of concrete. At that time the outer part has not no displacement and no stresses.Thanks for helping.

    Bhagwanjee Jha · Dr. Babasaheb Bhimrao Ambedkar Government Polytechnic

    I think a better construction technique here would be ---Construction of hybrid section at the end of the beam by using steel plate bolted with the concrete section. Instead of tension bars protruding out from ends, better provide bolts coming out from the beam and connecting them with the steel plate. The plate can be connected with the truss as you planned. Thanks

  • Does anyone have a Gateway-compatible vector for C-terminal protein tagging (GFP etc. pp)?

    Also including a signal peptide to introduce a protein of interest in frame after the signal peptide and in front of the fusion protein?

    Shaban Ahmed Ali Abdel-Raheem · Assiut University

    You are wellcome

  • Can anyone please provide me any reference for non bonding forcefield parameter for iodate anion???

    (IO3)- non bonding parameter for molecular dynamics simulation...

    Bojidarka B. Ivanova · Technische Universität Dortmund

    Mr. Sadhu,

    Please find below three refs about the quantum chemistry of your ion, but the first screening has shown that there have not data for the potential energies. may be somewhere in the cited reference would have...

    1. Ab initio calculations for some oxo-anions of chlorine, bromine and iodine, Christoph Oberle, Hans H. Eysel, Journal of Molecular Structure: THEOCHEM, Volume 280, Issue 1, 11 March 1993, Pages 107–115

    2. The Journal of Chemical Physics, Volume 70, Issue 9, 1979, Pages 4194-4198, Vibrations and force constants of the hexagonal lithium iodate crystal, Crettez, J., Misset, J., Coquet, E.

    3. The electronic structure of ClO−3, BrO−3 and IO−3: an SCF—Xα study, B.El-Issa, A. Hinchliffe, Journal of Molecular Structure, Volume 67, 1980, Pages 317–321

  • Is there a linear dimension unifying communication and consciousness?

    Semiotics as a unifying (universal) discipline can transcend the theoretical difficulties resulting from the differentiation of communication and consciousness.

    Shian-Loong Bernard Lew · Taylor's University

    Perhaps the seeming distinction between communication and consciousness evaporates once a common metaphor is found? I am thinking about Lakoff and Johnson's  (1980) Metaphor we live by. To pursue the matter along a more scientific line of argument (information and quantum-theoretic) it would be interesting to consider arguments that is more of a "quantum consciousness" nature

  • Miguel Maestro added an answer in Food Chemistry:
    How do I make aliquots of 1,25- dihydroxy Vitamin D3 in order to store it in active form?

    I have aliquot the same product from Sigma (D1530) in 100% ethanol previously at a concentration of 100 microM concentration and stored at -20 degree. But I am not finding any activity after some time. I am performing MTT and expecting to have some toxic effect on them as mentioned in many literature. I even got cytotoxicity for the first time, when I freshly aliquoted. But, after that I am unable to get the same result not even near to it.

    Miguel Maestro · University of A Coruña

    Our concentration of your main stock is aprox. 5 10-2M, we stored it a -80ºC in and amber vial and we work with aprox. 10-5_10-6M solutions in amber vials kept at -20ºC and they last at least for two weeks.

  • Does anyone know about any procedure to extract sterile blood for blood agar medium in an easy way?

    I am trying to prepare blood agar medium but i get contamination in the plates since the blood collected seems to be contaminated. Is there a way to get sterile blood or sterlize blood in an easy way?

    Lotfollah Behroo (لطف الله بهرو) · Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

    Firstly, prepare a clean sampling section and then,

    vide infra, plz;

    Inoculation of primary culture media ...

  • Do you know of any cost planning software, similar to the service presented at www.res-plan.com?

    The innovative service “Cost Planning” has been launched at www.res-plan.com. 
    The site contains video presentation of the service.

    I hope the service can be useful for some of you and your companies, institutes, contacts.

    I would be grateful for any questions, suggestions, comments about the site, presentation and service.

    Vladimir D. Ilyin · Russian Academy of Sciences

    Dear colleagues, I recommend to watch the video presentation of this service.

  • Can a collision-free motion planning algorithms for groups of wheeled robots be applied to multiple arm manipulators in a tight workspace?

    I am searching for possible solutions for planning collision free movements of multiple industrial arms in real-time. In familiarizing myself, I have come across a number of papers such as "reciprocal n-body collision avoidance (Berg et al, 2011)", but not as much  information on multiple arm motion planning.

    1) Is there any good starting paper for collision avoidance planning for multiple manipulators?

    2) Is it possible to generalize wheeled robot motion planning solutions to manipulator context?

    3) Are there any software libraries for real-time collision detection or motion planning applicable to this context ?

    Thanks.

    Kwame Nyarko · Technische Universität Chemnitz

    Thank you very much Sheraz and Azouaoui, your insights have been very helpful. For now I am considering applying OMPL or MSL for my purpose, and a suitable simulation tool to test out some already existing motion planners.

  • Christian Deimel added an answer in OpenFOAM:
    Which one is the appropriate relation to calculate omega in k-omega-SST openFoam?

    Dear researchers!

    As I mentioned in my earlier query regarding wind tunnel flow simulation and also as per your advice to use k-omega-SST instead of K-epsilon model.

    In CFD forum (attached link), there are some empirical relation to calculate k, epsilon and omega.

    There they suggest omega= [sq. root (k)]/l , but also attached a note:

    Please note that some CFD codes, Fluent, Phoenics and CFD-ACE for example, uses a different length-scale definition based on the mixing-length, and therefore the following formula should be used:

    omega=Cmu ^-1/4*[sq. root (k)]/l 

    Using both equations there is a huge (5times) difference in calculated value of omega. Which one is best for openFoam?

    Best regards

    Christian Deimel · Ruhr-Universität Bochum

    See attached link for an OpenFOAM epsilon BoCo based on the mixing length.

    It is the same as the second formula for epsilon mentioned in the Wiki-Link.

    Hence, you need to used the second formulation to calculate omega, as omega=epsilon/(Cmu * k)

  • Philip Lyons added an answer in Microbial Diversity:
    Is rarefaction essential when examining 16s amplicons from illumina NGS?

    I am examining 16s diversity from intestinal content of fish to look at the microbial diversity in each sample. Looking throught the literature, some papers use rarefaction analysis and some don't. Is it possible to compare diversity without losing so many sequences by rarefying? Is it possible to just report on each individual sample diversity so as to avoid losing so many possibly important sequences?

    Philip Lyons · University of Stirling

    Hi Alex, I mean that by bringing the no of sequences down to that of the sample with the lowest number of reads, I lose the reads from the samples with the greater numbers 

  • David Bruce Conn added an answer in Biosurveillance:
    What is understood, in terms of biosecurity and biosurveillance, by Early Warning Systems?

    My research group and me are inquiring about this question and we want to answer some isues about this topic, in addition to this general question, we want to know:

    -What is understood, exactly, by biosurveillance?
    -What is understood, in terms of biosecurity and biosurveillance, by Early Warning Systems?
    -From the point of view of biosurveillance, scientifics and experts, what is currently the role of citizenship?
    -There are tools, apps, guidelines, etc. whereby citizenship can collaborate or "enact" as alert system?
    -Where can we find documentation about this kind of issues?
    -What is a sentinel site or a sentinel web? and how it works?
    -What is the role of Internet into this new intelligence related with detecting pandemics and acting before it occurs?

    I have some stuff written about it in my blog: http://ebaes.blogspot.com.es/

    Thanks in advance, 

    Enrique

    David Bruce Conn · Berry College

    Enrique,

    Thanks for your excellent job of posing this question, and articulating many critical issues.  I will be following the discussion that I hope will ensue, and perhaps make some more comments of my own after seeing where the discussion goes.  It seems to me that this whole area has been inadequately defined and standardized.  I consider much of my work to be biosurveillance - looking for prevalence and distribution of pathogens in natural environments, primarily through the use of  sentinel organisms.  However, surveillance or biomonitoring (which term is best?) for vector  populations is also important.  I've attached a couple of relevant papers.  Best wishes, Bruce

  • Frédéric Dumont added an answer in Colectomy:
    Is it a must to close mesenteric defects after colectomy?

    After colectomy and restoring bowel continuity,

    is it a must to close mesenteric defects?

    Frédéric Dumont · Institut de Cancérologie Gustave Roussy

    I don't close the mesenteric defect but at the end of the procedure i range carefully the small bowell and the epiploon.