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  • Divaker Choubey added an answer in Acanthamoeba:
    Does working with Acanthamoeba spp. require containment conditions?

    Currently I am working with Acanthamoeba on the open bench, so I want to know if any containment conditions to work with this parasite.

    Divaker Choubey

    The ATCC requires a Bio-safety Level 2 to work with certain species of this organism. The best thing would be to consult your Institution's Bio-safety Officer immediately BEFORE starting ANY research work in a lab that is not certified to work with BSL-2 agents.

  • Deon Bezuidenhout added an answer in Carbodiimides:
    Is there a way to test 1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride (EDC)?

    We store our EDC in the freezer and access this chemical fairly frequently. Is there a way to easily determine whether or not it is still going to efficiently crosslink carboxyl groups to amines when paired with NHS?  Any guidance would be great.  

    Deon Bezuidenhout

    I agree with the comments above.  As EDC is  hygroscopic, I suggest you aliquot your stock out into small quantities (in a dry box), seal them well before placing in the freezer (or put them in a dessicator in the freezer if needed). Multiple opening of a larger chilled container will result in condensation of water in the reagents and resultant hydration of the EDC.

  • Debra Sharon Ferdinand added an answer in Evaluation Skills:
    How can I use both explicit and integrated methods of critical thinking instruction in the EFL classroom?

    I would like to adopt both explicit and integrated methods to foster analysis, synthesis and evaluation skills of language learners, and measure the differences in their speaking abilities.

    I know how each CT skill should be instructed, but using both of them seems to make the syllabus more complicated. 

    I intend to use both because it is considered the best way of instruction of CT in the literature, such as  Marin and Halpern (2011) .

    Debra Sharon Ferdinand

    I am suggesting that you use debating as a teaching strategy that allows for students to develop critical thinking skills in defending their arguments as wall as allow you to integrate other collaborative pedagogy in setting up the debate in teams. You should ensure that the debating topic relates to students prior reading/experience/societal/global issue to make it motivating for them. I am attaching a recent conference paper that was presented at this year's 16th Annual Scholarship of Teaching and Learning Conference in Indiana, U.S.A. which I hope can be useful in demonstrating how the latter is done.

    Best regards,


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The Debate (i.e., arguing for or against the topic, giving reasons to support or oppose it) is a dynamic teaching tool (for both f2f and online classes) that engages high school/university students’ critical thinking, communication, collaborative, and research skills, in mastering the course content across subject disciplines (O’Mahoney, 2015). A good debate topic (moot) is topical, relating to students’ prior reading, experience, or societal/global issue in motivating students to participate to win. The debate usually has three rounds: (1) Students make an initial argument for or against the moot, clarifying key concepts; (2) Convincingly rebut their opponents’ arguments; and (3) Summarize their arguments, rebutting or defending key points. Teachers are motivated by students’ enthusiastic exchanges, noting improvements in their understanding and mastery of the course content (Akerman & Neale, 2011). Students’ debate assessment include quality of their collaborative debating strategy, debating arguments, and presentation (includes eye contact and oratory skills).
      The 16th Annual Midwest Scholarship of Teaching and Learning (SoTL) Conference, Indiana University South Bend, Indiana, U.S.A.; 04/2015
  • Arash Malekian added an answer in Flood Modelling:
    Could anybody please explain how to find threshold level for delineate floods?

    Im a Sri Lankan and Im studying the floods in some district of Sri Lanka. It needs to delineate floods and non flooded areas during a high floods on 6th June 2008.

  • Charles Francis added an answer in Gravitational Field:
    Is the non locality of the gravitational field energy a serious problem for General Relativity (GRT)?



    "Although there is no room for such a thing in the energy–

    momentum tensor T, it is clear that there are situations where a ‘disembodied’

    gravitational energy is actually playing a physical role.

    Imagine  two massive bodies (planets, say). If they are close together (and we can

    suppose that they are instantaneously at rest relative to each other), then

    there will be a (negative) gravitational potential energy contribution which

    makes the total energy, and therefore the total mass, smaller than it would

    be if they are far apart.  Ignoring much tinier energy effects,

    such as distortions of each body’s shape due to the gravitational tidal field

    of the other, we see that the total contributions from the actual energy–

    momentum tensor T will be the same whether the two bodies are close

    together or far apart. Yet, the total mass/energy will differ in the two cases,

    and this difference would be attributed to the energy in the gravitational

    field itself (in fact a negative contribution, that is more sizeable when the

    bodies are close than when they are far apart)." 


    The same problem was also rised by Thirring, Kalman and Feynman in the FGT theory, they inserted the gravitational energy in the tensor equations...

    It is a problem of paramount importance which prevents the General relativity theory from describing any motion in which the hamiltonian is time dependent or rather in case of non isolated systems, or in case of non stationary interactions between different bodies.

    The attempt to model a free falling body in a gravitational field for GRT seems impossible.

    GRT has been tested  only for static or stationary systems where there is not a net exchange of energy (excluding gravitational radiation)

    Don't we need another GRAVITATIONAL THEORY which includes the results give by GRT in order to explain with a better accuracy the simple phenomenon like the free falling of a mass in a gravitational field?

    Charles Francis

    Clearly, Valentin, your claims of "dogma" are intended to be insulting, because only an idiot would think that anything in science is decided by dogma. Also, your claims that the LT is inconsistent are intended to be insulting, because the LT is a straightforward matrix multiplication, as taught to high school students on a regular basis. You are claiming that no physicist can do elementary mathematics. 

    What you actually mean is that the LT is inconsistent with the dogma of time as preached by Valentin, in spite of the fact that the dogma of Valentin has been shown wrong in many thousands of experiments, over more than a hundred years, and is now shown wrong on a daily basis in practical applications. This does indeed show that the vile accusations you make against others apply only to yourself.

  • Ouhader Hanan asked a question in LRP:
    Subtour elimination in Matlab ?

     I am currently using intlinprog (Mixed Integer Linear Programming) to solve LRP(location routing problem).I am now stuck at subtour elimination constraint and I don't know how to compute this on MATLAB. The subtour elimination method that I will be using is Miller-Tucker-Zemlin (MTZ) constraints.

    Can anyone help me? The constraints are:

     for all i                qi<=ui<=C

    for all i-j client                     ui-uj+xij*C<=C-qj   

  • Berj Kishmishian added an answer in Acupuncture:
    How to make sure that it is a sham acupuncture?

    In many acupuncture trials, there were sham acupuncture group?

    How to definite the sham acupuncture?

    Berj Kishmishian

    I agree with both Andreas and Liisa. Ultimately there is no true placebo for acupuncture, other than laser. However, laser acupuncture is not generally accessible in most clinics, therefore any potential study results would not be directly related to clinical practice.

    However, if the question is aimed at, does penetrative acupuncture yield a greater outcome than sham acupuncture? As Greg highlighted, sham acupuncture devices (Streitberger, Park, Takakura) have been validated, and if a study adheres to the STRICTA guidelines, I feel this would be the most robust method of comparing acupuncture to sham acupuncture. If that is the question you are trying to answer.


  • Luciana da Mata Mônaco asked a question in Papers:
    Is there some problem related to normalize ASL images before calculate CBF maps?

    I've noted a inversion of the order in recent papers.

  • Arash Malekian added an answer in Flood Modelling:
    What kind of software provide flood frequency analysis?


    Please recommend me any software is capable to calculate flood frequency analysis? 


  • Mahdi Khodadoost asked a question in Learning:
    Hi.Could you help to earn some good reference for learning comsol?

    I want to start working with comsol
    could you guide me?

  • Yuan-Yeu Yau added an answer in Plant Transformation Vectors:
    What is the effect of intravector  multiple insertion in plant transformation vector?

    Plant transformation and biotechnology 

    Yuan-Yeu Yau

    Hi Prithwi,

    The question is kind of vague. Do you mean several T-DNA cassettes in the same binary vector? I am not so sure about "multiple insertion" mean.

  • Erik B. Melchiorre added an answer in Environmental Geochemistry:
    Does anyone know of methane d13C AND dD data for serpentinite springs?

    Anyone know of methane d13C AND dD data for serpentinite springs? In particular, I am looking for both d13C AND dD for the Cedars, Oman, and Turkey. Thanks in advance!

    Erik B. Melchiorre

    Many Thanks!

    These were exactly what I was looking for!

  • Hossein Javadi added an answer in Theoretical Physics:
    Does the uncertainty principle violate the conservation of energy law?

    Aephraim Steinberg of the University of Toronto in Canada and his team of researchers have performed measurements of photons and showed that the act of measuring can introduce less uncertainty that is required by Heisenberg’s principle. Violation of Heisenberg’s Measurement-Disturbance Relationship by Weak Measurements


    Is reduced the amount of uncertainty by the development of precision our tools? Does Heisenberg's Energy-Time uncertainty inequality imply non-conservation of energy?

    Is the uncertainty principle a property of nature or a result of observer tools?

    Does the uncertainty principle prevents our better understanding of the universe?

    Seems physics has stopped at the border of the uncertainty principle and the speed of light.

    Is there nothing beyond what appears in the universe?

    Hossein Javadi

    Dear George
    When we are measuring some thing at large scale, might the amount of uncertainty is not considerable, but for sub atomic particles uncertainty has considerable role.

  • Michael Issigonis added an answer in Plato:
    Please, help.What is English for the name of Plato's primary school - /didacsaleon/?

    Please, help.What is English for the name of Plato's primary school - /didacsaleon/?

    Michael Issigonis


    You got excellent answers!

    I would like to add -from what I learned at school - that Plato didn't know what to call his school, so he named it after his next-door neighbour, Academos: Academy

  • Michael Issigonis added an answer in War:
    Do you believe that Biological war is more dangerous than physical war with weapons?

    Biological war is basically microbe based war. Even your drinking water will be poison.

    Michael Issigonis

    Very scary! It will be more dangerous. But even conventional weapons end up contaminating water and soil. Remember the Yugoslavia war of '99 with DU weapons?

    So many pilots from Italy died from leukaemia by just flying the bombs (before they dropped them), never mind receiving them on the ground.

  • Andrea Piroddi added an answer in Wireless Sensor Network:
    Anyone familiar with Random Number Generation in WSN?

    Hello , 

    I am writing a code for event detection in WSN. Generally we generate random number between (0,1) and we set a certain threshold (e.g temperature) or any randomly generated threshold .  I am having trouble with the threshold value . Beside (0,1) and temperature range . Is there any alternate method for setting the threshold value .


    Andrea Piroddi

    The design of effective event detection and query processing solutions has recently received increased attention from WSNs research community. The simplest techniques rely on defining a strict threshold value for the sensed phenomenon and alarming the system manager of any violations. However, in most recent applications of WSNs, event and query processing units are often complicated and require more than a
    predefined threshold value. One such emerging technique is to use machine learning (AI) to develop advanced event detection and query processing solutions.

    best regards

  • Hossein Karami asked a question in Argon:
    In GTAW and GMAW process, the Argon gas is better than Helium for Arc cleaning, Why?

    In GTAW and GMAW process, the Argon gas is better than Helium for Arc cleaning, Why?

  • Aram Bahrini added an answer in Decision Support:
    Anyone working on Graph Model for Conflict Resolution ii GMCR II, in shared water resource conflict?
    I need the help of this software
    Aram Bahrini

    Dear Ramadhan,

    Your email address has a problem and I cannot send you my responses. Please give me another email address

  • Araz Nasirian asked a question in MCDM:
    Can anyone introduce me one or more papers which use PROMETHEE Visualization (GAIA) for solving a MCDM problem, preferebly facility location problem?

    Since I am writing a paper in which PROMETHEE Visualization (GAIA) is applied to solve a logistics center location problem I need similar papers to see the gap area and the latest trend in this approach.

    I am thanking you for your comments.

  • Debra Sharon Ferdinand added an answer in Mathematics Teaching:
    What seminal research articles capture the way in which bureaucratic systems can work against quality mathematics teaching and learning?

    I have been looking for seminal articles on how some of the bureaucratic systems of Education, with quality management systems and highly prescribed lesson formats and so forth have constrained possible interventions aimed at increased quality and equity – particularly in mathematics education. I recall many years ago in England that highly structured lesson systems pushed some of the best teachers out. I would love to read further on research that has looked into how bureaucratisation of teachers work can get in the way of the core business of teachers and their focus on student learning. 

    Debra Sharon Ferdinand


    I too have not done much research in this area, but I can speak from experience that trying new strategies have not always been met favorably by both students and surprisingly, teachers. If it has never been done before, then everyone is skeptical about taking time to do something that may or may not work, so sometimes the innovation is knocked down from the start or just treated as not very important. Sometimes, it's just a matter of "it's not my idea" syndrome:-) I have included a link to what's available on RG and hope it can be useful.

    Best regards,


  • Olivier Monfort added an answer in Hydrogen Production:
    What are the best materials for hydrogen production? How can these materials be prepared? What techniques can be used for materials characterization?

    Dear friends, I am trying to learn more about hydrogen production by water splitting.

    Thanks in advance, Pedro Villegas

    Olivier Monfort

    TiO2 is the most widely used photocatalyst due to its low cost, non-toxicity, and rather good efficiency, but it is actice under UV. There is now a huge effort that is done to find photocatalysts that are photoactive under visible light in order to use wider spectral range of the sunlight. For such photocatalysts are not very successful but composite material or even doped materials are used to improve their efficiency. To find the best photocatalysts, you can orient you research on some photocatalytic reviews that present efficient photocatalysts.

  • Muhammed oda Mallah added an answer in Giardia:
    Can anyone advise why we use triophosphate isomerase (TPI) gene for detection Giardia lamblia assemblages (A,B,) instead other B-Giardian gene?

    triosphosphate isomerase (TPI) gene+B-giardian gene.

    Muhammed oda Mallah

    thank you for your helping.

  • Corrado Battisti added an answer in Applied Ecology:
    Which approach to reconstruct the human-induced and natural historical events in a remnant wetlands?

    As wildlife manager (and applied ecologist) of a protected area, I'm reconstructing the history of natural and anthropogenic events that have featuring a wetland remnant ecosystem embedded in a fragmented and urbanized landscape in the last thirty years. I have observed how the management of these systems should take particular account both deterministic/periodical events and rare, stochastic, unpredictable events ('black swan' events).
    I would like to know if this arena of historical applied ecology (Swetnam et al.) has already been investigated by some researcher in wetland management and which approach have been used.

    Corrado Battisti

    Dear colleague,

    thank you for your response. I download your paper and take your reference for a possible future citation. I will read carefully your work. Have a nice job! corrado

  • Tina Thulasi added an answer in Accelerator Mass Spectrometry:
    Which benthic foraminifer is suitable for AMS dating?

    Which benthic foraminifer is suitable for AMS dating?

    Tina Thulasi

    Mam, Only the species where the shells are well preserved will be considered for analysis.. I need to know which benthic foraminifera species is suitable for the age detection in Quaternary period???

  • Jan-Martin Wagner added an answer in Fermi Level:
    What happens to the Fermi level after we apply a bias voltage on the subtrate?

    I read that the Fermi level is only correct when the subtrate is in thermal equilibrium (no external voltage applied on). I'm curious about what happened, for example, to the fermi level of a fully-depleted p-n junction

    Jan-Martin Wagner


  • Sergei Esipov added an answer in El Salvador:
    Dear colleagues, do you know references about thresholds of annual rainfall and abundance of mosquitoes (Aedes and Anopheles)?

    Dear colleagues,

    I am working in national cartography of dengue and malaria risks in El Salvador using GIS. I am using Hierarchy Analysis Method, and one of the factors that I took into account is annual rainfall. I grouped each subfactor in different weights 1, 2, 3. For example according scientific literature about the relationship of Aedes mosquitoes and temperature: 1- (average temp less than 13 C) - Low mosquitoes activity; 2- (average temp. 13-20 C - moderate activity; 20-33 high activity). I found a lot of references that speaks about the importance of rainfall (linked to humidity conditions) about mosquitoes proliferation, however I didn't found any reference about rainfall thresholds. Could you give me some references please? Thank you very much for your kindly attention.

  • Hatsari Mitsudharmadi added an answer in Wind Tunnels:
    Can anyone help with my wind tunnel design question?

    I would like to know the guideline for the honeycomb 'diameter' - wind tunnel size ratio. So far I only got to know that the 'diameter' - length of this honeycomb is approx.1:8. Need to tune our newly constructed wind tunnel flows.

    Hatsari Mitsudharmadi

    Hi, Dr. Zambri

    There is a brief explanation on the function of the honeycomb in the wind tunnel in the follow link: http://navier.stanford.edu/bradshaw/tunnel/honeycomb.html.  In the link above, you can find  the ratio of the cell length to the cell diameter of the honeycomb and also some old references for designing the wind tunnel.

    I am just curious why you want to know the ratio of the diameter of the honeycomb to the size of the wind tunnel.  Usually the design of the wind tunnel will be expressed in term of contraction ratio and turbulence level.  I managed to improve the turbulence level of the wind tunnel with the contraction ratio of 4:1 from 0.7% to 0.35% by replacing the existing wire mesh with the finer one.  However I have to sacrifice the maximum speed that can be achieved as the pressure drop across the wire mesh increases.  Thus, we need to know the maximum pressure drop that can be handled by the blower used in the wind tunnel and the estimation of the pressure drop due to the wire mesh and honeycomb.


  • Yousef Ghollampoor asked a question in Seed Germination:
    What's the Best water temperatures for scarification jojoba seeds to per treatment germination?

    What's the Best ways to jojoba (Simmondsia chinesis) seeds germination (Considering that jojoba seed germinate hardly)? 

  • Silvana Zammit added an answer in Pediatrics:
    Has anyone used a validated questionnaire on practice and perceptions of paediatricians regarding adolescent transitional care?

    I am doing an MSc and my dissertation is on practice and perceptions of paediatricians & adult physicians in this field in Malta.  Can anyone direct me to a ready made tool(questionnaire) that I can use?

    Silvana Zammit

    My aim in the study on Adolescent transition in Malta is to assess the knowledge, practice and perceptions of paediatricians and adult physicians regarding transition.  I plan to send a questionnaire to ask about these issues and then to set up interviews to gain more insight into the local situation.  I would appreciate any help.