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  • What is the best way to determine and calculate the amount of water needed for cement hydration in wood-cement particleboard panels?
    Portland cement Type I.
    Different types of wood species.
    There are several methods used for this estimation, from your experiences in this field what is the best way for doing this?
    Thomas R. Paradise · University of Arkansas

    we've used thermal mass loss in the past... on the various cement iterations, and the various wood types/species/treatments.  The combined materials are weighed very carefully before and after full curing.  This only works though with samples, and not in-situ.

  • How do you plot the wind speed contour for the tropical cyclones in their pathways for different altitudes?

    I need to draw the contour of wind speed for cyclones

    Thomas R. Paradise · University of Arkansas

    in terms of visualization theory, you could color-code your altitudinal ranges, or simplify the maps by dividing each representation by altitude or altitudinal ranges.  You should not represent the various wind vectors or isovents/isovels, at various altitudes on the same map.  It will not be clear to the viewer (percipient) if you combine ALL vectors/contours on the same map, WITH the alititudal ranges as well.  Either define each range or grouping by color, or separate them on different maps (diptychs, triptychs, etc).  Good luck, TRP

  • Which sociologist in classical term (1700-1900) was interested in natural sciences like ecology?

    Is there any study has been done related this issue?

    Edward M. Crenshaw · The Ohio State University

    Well, I guess that'll teach me to post this stuff quickly and without a proof-read.  And Howard, the question was who, among early SOCIOLOGISTS, had the most interests in natural science...not who was the most politically correct.  E.O. Wilson, Chagnon, etc. are NOT sociologists, nor are they "early."  

    And if Spencer was a social darwinist, he would have had to do that in contradiction to his own understanding of biology.  Spencer made comments about the poor that could be interpreted that way UNLESS you've actually read the whole text (as I have).  His notion that improving society could improve the genome rested on Lamarck, not Darwin.  And of course I am not alone in thinking that Spencer has been unjustly maligned (e.g., Jonathan Turner...the best purveyor of classical theory in our business).

    Like many sociologists, you seem dismissive of biological contributions to social science, which is too bad.  Sociology is very gradually being dragged (kicking and screaming) into the modern era, and accepting the biological basis of much of social behavior is part and parcel of that updating process.  Enjoy the ride if you can.

  • Hanno Krieger added an answer in Phototherapy:
    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?

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    Dear Marcel,

    I´ve read the highly interesting cited paper and have tried to understand the statements and results. There is no doubt that extraocular sensors are able to detect light, we already know them from different animals. And as this paper shows, the received signals are able to provoke reactions of some organisms.

    But coming back to the original question "human phototherapy" you have to provide sufficient light intensities to reach some however constructed receptors within the human brain. And therefore I repeat my statement, our adult brain, the brain of older people, is to dark for significant photoreactions. And of course, first you need to define and find the receptors.

  • Gert Nolze added an answer in Nickel:
    Will the coating be evident in SEM images from the deposited SiC on nickel substrate?

    only substrate peaks are coming. What can be the reason. Please suggest any other methods to confirm the coated material composition.

    XRD was carried out at 0.3 deg incident angle

    Gert Nolze · Bundesanstalt für Materialforschung und -prüfung

    How thick is your coating, and which techniques did you use to confim the coating process?

  • Kristie Grove Bridges added an answer in Saliva:
    Does the salivary flow rate in children differs from the rate in adults?

    When recording unstimulated salivary flow rate, we consider 0.3-0.4 ml/min as regular and less than 0.1 ml/min as oligosialia. These values are measured for adults. Shall we use those values also for children? I could not identify any paper or recommendation regarding the evaluation of the salivary flow rate in children with other values than for adults. Is the normal salivary flow rate constant over the ages?

  • Kashyap Thumar added an answer in LC-MS:
    I am not getting Precursor/Product ion of Diacylgymnemic acid using LC-ESI-MS/MS after so many trials. Any suggestions?

    Whatever precursor/product ions get it will not be repeated the next day. So, I can't finalize the method.

    Kashyap Thumar · Saurashtra University

    Dear all,

    thanks for your suggestions

    as per your suggestion, I already try ESI and APCI source for ionization of deacylgemnemic acid.

    we have LCMS 8030 of Shimadzu.

    Actually I facing problem that during the parent scanning, mostly I found the highest instensity at 647.4 m/z in positive mode which I cant correlate with the structure. if possible than please suggest me probable moiety  formed from DAGA. ( 682.847 actual molecular weight).

    I have attached certificate of analysis of my compound, from that I have procured.

    some times I also found the 681.2m/z in negative mode but the intensity is very less and not coming to all solutions which were prepared at different times.

    we are assure that our instrument is stable with all other analytes which were currently going on...

  • Can anyone identify the plant species?

    This is Zingiber sp. but I would like to request, if anyone can say what species of Zingiber this is.

    I would be grateful to him/her for identifying the species.

    Shah Md. Golam Gousul Azam · University of Naples Federico II

    Thanks Narayanan

  • Is Loretnz symmetry conserved for all velocity ranges?

    I want to know whether Lorentz symmetry is conserved for all the velocity ranges or not?

    Is the Lorentz invariance completely related to Lorentz symmetry; i.e. if Lorentz symmetry conserved then Lorentz invariance is also conserved or there are certain conditions where the Lorentz invariance conserved while Lorentz symmetry is not? what are they if there are such conditions.

    The problem is the following : we have two observers, located at the same point, each of them uses an orthonormal frame to measure vectors, these measures are done in the same vector space, which is the common tangent space to the manifold (representing the 4 dimensional niverse) at this point. One goes from one frame to the other by a matrix of the Lorentz group (becaause the bases areorthonormal), and the formulas explicit this matrix.

    The key points are the following :

    1. The group and the matrix act on vectors, and not coordinates of points. Only in the context of special relativity is it possible to consider coordinates.

    2. The two observers must be located at the same point. if not their tangent spaces (where vectors live) are not the same. Only in special relativity is it possible to consider two distant observers.

    The bad habit of physicists to consider only affine spaces, frames, coordinates, and the weak demonstration of the transformations formulas (repeated word for word for a century) muddle everything. Actually it is more illuminating in the General Relativity context, but one must be very precise in stating the basic assumptions. The key assumptions are :

    i) the existence of a Lorentz metric

    ii) all observers travel on world lines, and their velocity (derivative with respect to their proper time) has the same length as expressed in the Lorentz metric (which assure that their clock run at the same rate)

    iii) in the choice of their 4 dimensional frames, the 4th vector (the time vector) is oriented along their velocity (another choice would be difficult to conceive)

    Add the generalmathematical expression of a matrix of the Lorentz group andyou have the solution.

    Of course this is a mathematical proof. It has been checked experimentally, and this validates the assumptions.

    As for the motion of distant stars this is a totally different story. First it is necessary to introduce a tool to compare vectors in different tangent spaces, this is a connection, linked to the gravitational field. Second one needs an adequate representation of rotations of material bodies in a 4 dimensional space,which is not given simply by a Lorentz matrix (this is where spinors enter). Third of course one needs a general theory of interacting material bodies.

  • Is anyone familiar with non-destructive estimates of aboveground biomass using terrestrial laser scanning?

    Terrestrial laser scanning (such as LIDAR) is an active remote sensing technique that allows the structure of vegetation to be 3D-mapped to the finest resolution.

    Please provide links to research articles and other pertinent information.

    Victor Hugo Gonzalez Jaramillo · Universidad Técnica Particular de Loja

    Hello Mounir, there is a lot of literature but I think that one interesting is:;
    Classifying species of individual trees by intensity and structure features derived from airborne laser scanner data
    Por: Orka, Hans Ole; Naesset, Erik; Bollandsas, Ole Martin
    REMOTE SENSING OF ENVIRONMENT Volumen: 113 Número: 6 Páginas: 1163-1174 Publication date:JUN 15 2009

  • Nishat Jaleel asked a question in DMSO:
    How long can I store cur cumin solution?


    I prepare different molar concentrations of cur cumin in DMSO for my experiments. How long can they be stored at -20 degrees centigrade? And how should we thaw them before use : on ice or just let them naturally come at room temperature?

  • Alan Wartenberg added an answer in Addiction:
    Does anyone know of research which might support the proposition that a person can be allergic to alcohol rather than addicted to it?

    As an addiction specialist counsellor I often meet people that should not drink alcohol as they have a strong reaction to it, particularly a strong physiological response. It impairs their functioning.

    Alan Wartenberg · U.S. Department of Veterans Affairs

    This is a misuse of the term "allergy," which implies immune related problems, involving antibody formation.  Clearly, there are people who have "adverse drug reactions" or ADRs, which is entirely different from, and really should be differentiated by medical professionals from "allergy."  People who develop flushing, for example, after drinking may have abnormal isoenzymes of acetaldehyde dehydogenase, or an actual decrease in levels of that enzyme, so that acetaldehyde accumulates when they drink and results in vasodilatation.  In others, however, flushing may be related from alcohol release of histamine from mast cells by unknown, but NOT allergy-mediated release mechanisms. The disinhibition and aggression/violence that occurs with alcohol in many individuals is also not "allergy," but more likely related to an exaggerated disinhibitory response of alcohol on frontal cortex release secondary to prior trauma, physical or emotional, and impaired emotional modulation in those individuals.  Again,calling this allergy may be understandable to the clinician and to the patient, but is scientifically and semantically incorrect.

  • Marcia Ratner added an answer in Stimulation:
    Does anyone know about the regulate model of brain pacemaker used in neurosurgery for Parkinson's disease?

    Thank you very much for your attention. I am very interested to know the working model of brain pacemaker used for Parkinson's disease, it stimulates the nucleus continuously or in a special stimulate rhythm?

    Thank you!

    Marcia Ratner · Boston University School of Medicine

    Irrespective of whether the device has a manually adjusted pulse or one that responds automatically based LFPs the device still needs to be on in order to induce a performance improvement.  In practice most patients prefer to leave the device on all the time, even when they are sleeping so that they can move better when they wake up in the middle of the night.  A device that uses biofeedback to optimize signal intensity eliminates the need for the patient or neurologist to adjust the device to optimize performance but the device still needs to be turned on.  

  • Daniel Elad added an answer in Carbapenemase:
    Are currently available methods sufficient for rapid detection of Carbapenemase- producing Enterobacteriaceae in order to prevent outbreaks?

    To control the spread of carbapenemase-producing microorganisms, it is necessary to rapidly detect such organisms in patients with risk factors, primarily those hospitalized abroad.

    Daniel Elad · Kimron Veterinary Institute

    Just look for chromogenic ESBL detection media on Google and you will come up with several such as CHROMagar™ ESBL, Brilliance ESBL Agar and chromID ESBL, to name a few. 

  • Ab Ka added an answer in Genetic Algorithm:
    How can I tune the controller parameters and gain Genetic Algorithm with ODE solver?
    I am using the Robotics Toolbox for Matlab with ode15s solver to make a simulation of my controllers for a 5DOF manipulator, all things work and I have a result, but I want to have a best result by choosing the best values for the controller parameters and gains, for that I'm trying to use the Genetic Algorithm to tune the controller parameters and gains, but really I can't understand how to manage them together (ode15s and Genetic Algorithm).

    Notice that the model of the manipulator are generated by using the Robotics Toolbox.
    Ab Ka · De Montfort University

    GA can be used  for optimization and estimate parameters in (model or controller). you need to write a proper opjectiveFcn in the GA code. I am not really sure what you mean ode 15s? As I know that ode 15s it is away to use step value of the variables in the integrator solver.

  • Faisal Alzahrani asked a question in Blood Cells:
    Can I measure the amount of DNA damage/repair on blood sample?

    For example ; Do we need to grow them back in culture after we obtain them from the patient, then we extract the the RNA and Protein?

    Can blood cells ( all types) divide on in vitro ? any idea about the doubling time ?

    Thank you very much in advance ;) 

  • Jayesh Sonawane added an answer in Curve Fitting:
    How to calculate Rct value and curve fitting using Zsimpwin software ?

    I want to know how to calculate Rct value and curve fitting using Nyquist plot. I have Zsimpwin. I am new in this field. Please help me.  Thank you, 

    Jayesh Sonawane · IITB-Monash Research Academy

    Thanks sir, 

    I have coated polymer on anode. 

    Now I have to just add R2 and R3, Am I right ?

    Thank you, 


    - Jayesh

  • Bishnu Regmi asked a question in Base Pairing:
    How many base pairs are typically required for a hairpin?

    I am trying to design some DNA probes.

  • Does anyone have recommendations for parameters' correlation with aggression?

    I'm trying to create a theme, where aggression correlated with other phenomena, but it must have a pedagogical aim. I was thinking about relationship between parenting style and aggression, but this theme is psychological. Any recommendations for theme that will have pedagogical aim (theme has to be from pedagogy)?

    Sérgio Eustáquio Silva · City Hall of Belo Horizonte, Brazil

    Dear Robert,
    Some issues that trouble me:
    Aggressiveness and school climate (such as school climate influences the aggressiveness of students);
    Teacher relationship vs student and school violence (such as teachers and schools can contribute or not to increase school violence);
    School violence and socioeconomic level of the students (correlation between the socioeconomic level of the students and school violence);
    Gender and school violence (such as gender relations influence school violence);
    Color / ethnicity and school violence (such as color ratio / ethnicity influence school violence and whether a correlation exists between these variables);
    Students who have been subjected to violence are more aggressive in school? (correlation between these factors ...)
    If you have any specific context that in theory could help to reduce the levels of aggression, it can also be tested. For example. in a project that aims to reduce aggressiveness or violence ... groups that have yoga classes that develop projects of non-violence, human values ... tested against groups who do not develop such projects ...
    Are some suggestions. I do not know, however, to its context such relationships are important. These issues also are related to my belief that aggression is due more to external and contextual factors than the innate tendencies of individuals, while recognizing that as well. But I think the environment has a greater explanatory factor for aggression ... Think about your context and which could be relevant to you.
    There is also the problem of data, if you have them or not ... but I ventured to give a few words for you ...
    See you later,

  • Gert Nolze 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?

    Gert Nolze · Bundesanstalt für Materialforschung und -prüfung

    It would be good to get an impression about your measurement. Could you post an image of the diffractogram?

  • Aristotelis M. Zaras added an answer in Gaussian:
    How can we prove the mechanism of DA reactions with Gaussian?

    I have Gaussian output data and I want to prove mechanism of Diels Alder 

    Aristotelis M. Zaras · French National Centre for Scientific Research

    Dear Fatemeh

    please if you could be more specific on which reaction you are trying to prove?

    I will try to be more helpful:

    In order to prove your reaction you need to locate the corresponding Transition State

    which will lead to your desired products and thereafter verify it by running

    additional IRC calculations.

    I have done the opposite (production of 1,3-butadien-2-ol)

    for a Retro (Reverse) - Diels Alder Reaction.

    More details can be found in this publication:


    Hope this helps

  • Snehasish Dutta Gupta added an answer in Phloem:
    Can anyone suggest an efficient non invasive method to measure the ion flow in the stem of a plant?

    I am familiar with a protocol in which we cut the leaves soak in water and take the electrical conductance of the solution to measure the ionic difference between treated and untreated samples. But can anyone suggest a non-invasive method through which I can measure the ions and particle uptake and flow through stem or phloem without  cutting parts of the plant.

    Snehasish Dutta Gupta · IIT Kharagpur

    Acoustic sensor may work to measure the ion flow in the stem.

  • Nabeel Al-Yateem asked a question in Biostatistics:
    Can somebody recommend a text book for biostatistics for health sciences that for undergraduates, that is simple, clear and cover important topics?

    Can somebody recommend a text book for biostatistics for health sciences that for undergraduates, that is simple, clear and cover ALL the important topics? Thanks

  • Ghaleb AL-Dahash asked a question in Particle Size:
    Does the increase of Energy of laser pulse lead to decrease or increase nanoparticles size in semiconductors collidle?

    Many papers said increase and others said decrease particle size. Are this behavior for all cases? or what?

  • How do bacteria develop multi-drug resistance?

    Methicilin-resistant S. aureus were originally resistant to Methicilin but later on develop resistance to many other antibiotics. Similarly, vancomycin resistant Enterococci (VRE) also develop multi-drug resistance.  Why it is so often that bacteria develop multiple resistance? How do they acquire the multiple resistance? 

    Daniel Elad · Kimron Veterinary Institute

    In addition to mutation and gene transfer, mentioned previously, some resistance mechanisms that develop against one drug, may affect other drugs, to which the microorganism was never exposed, as well. For example an eflux pump aimed a removing one drug may remove other drugs too. Or, the entry restriction of one drug, for example by modifying pore size, may inhibit the entry of several other drugs as well.

  • Sandro Conrad added an answer in Comet Assay:
    Can anyone provide a general software for a comet assay?

    I recently performed a comet assay and therefore I need a software for scoring purpose. Kindly help me in this matter.

    Thanking you.

  • Why do digitized polygons change shape automatically in ArcGIS 10.2?

    As I am digitizing polygons in 10.2 ArcGIS, sometimes the vertices are getting deleted automatically and also it does not close as it should by clicking on the last vertex. 

    2. The final product has an altered shape that it takes on its own.

    3. Even while editing vertices as I add a new vertex it deletes the previous one.

    4. Also, I tried converting from lines to polygon. That also does not match exactly.

    I am frustrated. Any help would be appreciated. 

    Victor Hugo Gonzalez Jaramillo · Universidad Técnica Particular de Loja

    OK, this is very helpful to know why some problems could occur. In general when you add a new shapefile the data frame adopt the same reference system.

  • Is there any impact of LED on plant photoreceptors?

    LED irradiation has proved to be effective for plant growth and development.

  • Is anyone aware of current research on the consequences or treatment protocols for Cocaethylene addiction?

    There seems to me to be a black hole in the literature regarding Cocaethylene. My research (independently) has suggested a much more prominent awareness of the increased euphoric effects rewarding the addict despite their knowledge of the higher chance of sudden death and/or myocardial infarction within the Cocaine and Alcohol Addicts realm than there is in the Substance Abuse Research data bases or Educational literature... calling for the necessity of further research. Is anyone aware of current research on the consequences or treatment protocols for Cocaethylene addiction?

    Alan Wartenberg · U.S. Department of Veterans Affairs

    There is no evidence that cocaethylene per se has activity that is different from cocaine itself or alcohol itself, other than the potential for prolongation of the usually short half-life of cocaine.  However, in conversations with thousands of people who used cocaine and alcohol together, patients have told me they felt the cocaine more intensely but not for a more prolonged period of time. However, there is clinical evidence that the cardiac toxicity of cocaine may be prolonged in drinkers, perhaps because of the chronicity of cocaethylene duration.  Interesting question whether cocaethylene may have prolonged psychoactive effects, but am aware of no evidence on that.

  • Does anyone know where to order GPS collars to study small carnivores (1.5 – 2.0 kg) movements?

    The main aim will be to study animal movements towards human infrastructures, so we will need to have fine scales movements.

    Damian Stuart Morrant · James Cook University