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  • Qing He added an answer in tDCS:
    How could I measure one's EEG after it accepts tDCS?

    As we know it will take a long time for us to make subjects' resistance down before having an EEG test, while the aftereffect of tDCS may not last for a long time for some tasks.

    Qing He · Chinese Academy of Sciences

    Where could we buy a specific tES-EEG cap?

  • How can I do assignments of electronic transitions in TD-DFT analysis of a molecule?

    This is part of output file of TD-DFT analysis of a molecule. My question is that if I want to do assignment corresponding to excited state 1, how would i come to know, whether it is pai to pai* or n to pai* transition. 

    Excited State   1:   Singlet-A      3.7746 eV  328.47 nm  f=0.0681

          71 -> 76         0.14554

          72 -> 73         0.66092

     This state for optimization and/or second-order correction.

     Total Energy, E(RPA) =  -1245.04053734   

     Copying the excited state density for this state as the 1-particle RhoCI density.

     Excited State   2:   Singlet-A      4.6647 eV  265.79 nm  f=0.0590

          68 -> 73         0.41032

          69 -> 73         0.41521

          70 -> 73         0.25779

          71 -> 73        -0.24279

     Excited State   3:   Singlet-A      4.7881 eV  258.94 nm  f=0.3652

          68 -> 73         0.20008

          69 -> 73         0.14131

          71 -> 73         0.53757

          72 -> 74        -0.29181

     Excited State   4:   Singlet-A      4.8407 eV  256.13 nm  f=0.0656

          68 -> 73         0.10648

          71 -> 73         0.24108

          72 -> 74         0.63660

     Excited State   5:   Singlet-A      4.8994 eV  253.06 nm  f=0.0012

          72 -> 75         0.70050

    Davide Angelone · University of Groningen

    If we use as example the first transition you have: the most of the transition is due to the orbital 72 -> 73, observing the shapes of the MOs you can define if they are pi, n, or pi*. You can determine qualitatively whether they are pi, n or pi* also comparing the absolute energies of the orbitals toward the Fermi level.

  • Frederic Urbain added an answer in Rural Health:
    Can anyone suggest a much better interaction method, rather than face to face, for the rural women?
    I used various methods and found face to face method is the best.
    Frederic Urbain · Université de Versailles Saint-Quentin

     It depends on what is yous purpose ? If you want to evaluate their knowings, a questionnary will be good enough. If you want to know much deeper what they beleive, it needs face to face interviews with open guides. If your purpose is to give them knowings, I believe the better way should be peer-groups with an expert here to answer the questions raised by the group. But of course this must depends on local culture

  • Ramona Pezzotta added an answer in SIMS:
    Can you help me identify this bacteria?

    I have done every possible combination of bacteria and cannot identify its name, the bacterium I need to identify has the following remarks :   Using PEA agar

    Gram +, shaped like grapes, TSI A/ANG, growth on stab site, nitrate -( after Zn turned red), Citrate -( green slant), Urease +, SIMS +H2S, Indole +, BE +, Catalase -, MR -, VP +.

    Possibilities of S. Aureus, but test doesn't match!

    Ramona Pezzotta · Spedali Civili di Brescia

    The catalse is NEGATIVE... This makes it difficult to be Gram negative... Most of the Gram- are Catalase Positive!

  • Frederic Urbain added an answer in Depression:
    Which cut-off should I use for Edinburgh Postnatal Depression Scale on fathers ?

    According to http://www.ncbi.nlm.nih.gov/pubmed/25293375, the EPDS among men with a cut-off at 7 has a 75% sensitivity. But in other studies (Zelkowitz 2001 and Edmonson 2010, Massoudi 2013, with a higher cut-off we find a higher sensitivity. How is-it possible ?

    Frederic Urbain · Université de Versailles Saint-Quentin

     Thank you for this excellent answer, Béatrice. Unfortunately, I don't think that I am allowed to do like this : indeed, our purpose is to determinate the ratio of MDE in young fathers. So, I can't make the measurements and then choose the cut-off in a way the results will match wih our hypothesis, it would be bad research ;-)
    But you are right, I can't make a comparison between these studies because they studied differents things in different groups. I need to chose the closest one from our population and object of study.

    I will read with great interest your work about depression and anxiety among hysterectomised women.

  • Is relative simultaneity a misinterpretation of Special Relativity?

    I really need a lot of feedback on this particular issue.

    I think that relative simultaneity is a computational effect of no consequences to real temporal relations. This is based on my analysis of simultaneous trajectories.

    My claim of apparent nature of relative simultaneity is based on the assertion that relative lengths of rigid objects or points moving at a constant relative distance to each other in a stationary system are not conserved (in general ) in the moving system after Lorentz transformation when expressing multiple points trajectories in terms of common time of the moving system.

    More details in the linked document and relevant draft article available from my RG profile

    Stefano Quattrini · Ordine degli ingegneri della provincia di Ancona

    Eric and Ilja,

    I think the problem is always the same. In order to say something uncontrovertible about the clocks they have to be brought back together like in the experiment of Hafele and Keating. In other cases there will always be ambiguities on how to state experimentally that one is delaying respect to the other.

    The only way to compare clocks at a distance effectively is to use the quantum entanglment tecnique which apparently was not used yet.

    Some authors propsed the experiment of satellites distributed along the orbit of the Earth around the Sun in order to detect gravitational waves through the clock-rate differences of the orbiting clocks. The most effective way to sync them, according to their opinion, is to use quantum entangled states, every  clock which is far from the other for several million kilometers, is istantanously in sync with the Others, thanks to the quantum entagled phases which are induced instantaneously.

     "Simultaneous measurement of clock-rates at different phases of a passing GW provides an attractive alternative to the interferometric detection of temporal variations in distance between test masses separated by less than a GW wavelength, currently envisioned for the eLISA mission. "

  • Peter T Breuer added an answer in Academic:
    What's the year of publication?

    I'm doing an academic work, using this paper as reference, and I would like to know the year, please

    Thank you for your help

    Peter T Breuer · Birmingham City University

    Google whispers to me that it's 2003.

    Maybe the authors would be the best people to ask!

    Gerner and Bryan, ..., In Woodroffe and Furness (eds), Coastal GIS 2003: An integrated Approach to Australian Coastal Issues, Wollongong Papers on Maritime Policy, No. 14 (Wollongong, NSW: Centre for Maritime Policy, 2003, Australia), p. 415-430. 

    That sounds like a collection of technical reports or workshop abstracts, but what do I know. I only know what Google tells me.



  • Mohamed Salah Hemdan asked a question in Coding:
    Matlab code to genrate Random diagonal code?

    I need Matlab code to generate Random Diagonal RD code for OCDMA . Is there any in-build function in Matlab ?

  • Can i get help with a link to download an open access file for AHP Software (Analytic Hierarchy Process) used for Multi-criteria Decision Analysis?

    Can i get help with a link to download an open access file for AHP Software (Analytic Hierarchy Process) used for Multi-criteria Decision Analysis?

  • Graphene oxide/water simulation?

    Dear all

    I recently performed molecular dynamics simulation of mix Graphene oxide in water system using ReaxFF potential. I surprisingly noticed that some hydroxyl groups of graphene oxide were detached  and diffused between the water molecules.It make water solution of graphehe oxide basic but it is acidic from experiment. what's going on here?

  • Karen Noonan asked a question in other:
    What makes abdominal pain the identifying symptom for suggestion of porphyria?

    I would like to know if abdominal pain is the identifying  symptom present for people with porphyria or can they have other symptoms and not abdominal involvement at all, such as psychosis. thanks

  • How can I produce homogeneous mix of fiber and PE beside using extruder machine?

    I am working on natural fiber composite and wish to get a homogeneous mix of fiber and PE composite with simple method exclude extruder machine.

    Mohd Iqbal Misnon · Universiti Teknologi MARA

    Using the simple method such a mixer is right but the reduction in mechanical properties is expected.

  • Mohd Iqbal Misnon asked a question in Resins:
    Has anybody use Hetron FR992 resin?

    I working on the natural fibre composite and one of the purpose is to enhance its flame resistance properties. I just want to know several details on the mixture between this resin with the catalyst wether it can just use the MEKP alone or need other chemicals in the mixture.

  • Pardis Goudarzian asked a question in Nano:
    What is the best way for nanoparticle spraying?

    there is two way for nano particle spraying, normal way and aerosol technique (using nebulizer). is there another way for spraying nano particle to optimize the capability of penetrating?

  • I am interested in the effect of multi-tasking employees on quality of work. Thoughts?

    My experience and observation tells me that many corporate businesses have adopted a "multi-tasking" approach for their employees to resource their business projects - asking an employee to be part of a team on more than one project at a time, in the company's desire to hit "utilisation percentage targets" - with the result that the employees find themselves:

    1. Stressed and feeling "under pressure" to perform constantly, interfering with a balanced and thought through decision making process

    2. Unable to complete the task or assignment to their own satisfaction, often having to provide, by their own view, "sub-standard" work to satisfy time constraints and senior management demands. So essentially quality suffers and companies wonder why they fail to get repeat business due to customer dissatisfaction!

    3. Physically and emotionally exhausted so that they have "lost" their creative or innovative desires, or even ability. Many such people complain about a relentless cycle of work - eat - sleep - work with no time to "think outside of the box".

    I would love to see what research has been done to prove or disprove these observations.

    Negin Minaei · Royal Agricultural University

    From psychology point of view, recent articles suggest multitasking damages brain, leads to memory impairment, lack of concentration and increases the stress level, and in the long run decrease the efficiency of an individual. There was a myth about those with higher IQ level can do 3 tasks simultaneously without losing focus, but recent studies mention it's not healthy.Even if the tasks are simple and stress-free like using Facebook or replying to emails or talking to phone, still it can affect learning and the level of performance.

  • Suhail A. Doi added an answer in Software Design:
    Is there a software that makes meta analysis easier to compile and analyse?

    I am trying to do some meta analysis for the first time and am finding compiling trials into a database very difficult. I could use excel but wanted to ask experts if there is another software designed for this. Thank you for your help.

    Suhail A. Doi · Australian National University

    MetaXL (www.epigear.com) is very user friendly and free

  • Eugenia A. Sar added an answer in Algae Culture:
    Can someone help in identifying this species?

    I have been getting different ID from different people.. for this particular species. so need some help to ID it. Have attached 2 photos, one taken at 20x and the other at 40x.



    Sumantha N

    Eugenia A. Sar · National University of La Plata

    Dear Sumantha:

    The opinion of Dr. Komarek is more qualified than you can receive. He is a specialist in Cyanobacteria.

    All the best.


  • Han Ping Fung added an answer in Likert Scale:
    What kind of scales do researchers usually conduct when investigating about language attitudes?

     Likert Scale

    Han Ping Fung · Hewlett-Packard

    Hi Soumia,

    From the above list, most of them are in Likert scale.  Suggesting the following:

    1) Perform a thorough literature review & decide on which instrument / survey questionnaire for language attitude that you are going to adopt - this include your research problem, research objective & research context.

    2) If the precedent / well known survey questionnaire you are adopting is based on even or 4-point LIkert scale then you don't face the respondents sitting on the fence issue i.e. keep choosing N for Neutral or Unsure etc.  Try to avoid dichotomous questionnaire that serve either Yes / No as it inherits low explanatory power to represent respondents' opinion / experience.

    3) If the well known survey questionnaire you'd adopted have odd or 5-point Likert scale which includes N for Neutral or Unsure etc. and most of the respondents choosing N, then you need to find out why through a pilot test & sitting down with the pilot test respondents e.g. respondents don't understand the questions, question's language translation problem from original to local language, questionnaire too long & too tedious to fill up, or sometimes the questionnaire you'd adopted might not be reliable to be deployed on the respondents you are surveying etc.

    4) If you'd fixed the above problem, you can redo the pilot test to check for its Cronbach Alpha Reliability which should be > 0.7.  Some scholars / researchers also did change / adapt the survey questionnaire from odd 5-point to even 4-point Likert scale so that respondent can't choose N.  Whether you adopt or adapt the survey questionnaire pls get approval from the original owner of the questionnaire.  Wishing you all the best.



  • Artur Braun added an answer in Phonons:
    Can light and electrons of same extra energies scatter the phonon in the same way?

    let's say energy of 1.3eV to an electron in silicon it went to conduction band. remaining .2eV energy of electron moves this free particle around crystal. this electron will feel scattering from phonons. can i expect that the phonon frequency which observe from raman or infrared frequencies can scatter much ?

    Artur Braun · Empa - Swiss Federal Laboratories for Materials Science and Technology

    Interesting question. Do you have to include in the math the mass of the electron? Momentum might eventually play a role, in addition to energy.

  • Artur Braun added an answer in SAXS:
    Where can I learn about the mathematics supporting and used in performing a zero concentration extrapolation on SAXS/WAXS data?

    I am interested to better understand the mathematics supporting and used in performing a zero concentration extrapolation on small-angle and wide-angle x-ray/neutron scattering. Can anyone recommend a good source?

    Artur Braun · Empa - Swiss Federal Laboratories for Materials Science and Technology

    This is a very interesting SAXS and SANS question to which I have no other and better answer than looking at Glatter Kratky's book, which is now fortunately open source .pdf in the internet. Also fortunately, there are still prominent SAXS people alive, though seniors, and I suggest you find them and send them an email with your request. Check out Dr. Wilfried Gille in Germany. He does the mathematics. Then check out people like Svergun, Jan Ilavsky at ANL, Andrew Allen at NIST, and Günther Goerigk at HZB in Berlin. The latter knows a handful of contacts also in Berlin who do SAXS. And maybe you find S. (Sunil) K. Singha. And maybe try Soenke Seifert at APS. these are al SAXS people and may have an idea about the math as well.I stopped SAXS since I could not sell my results at a high enough price. But it's good to see SAXS and SAND coming up again. Good luck !

  • Igor L Shabalin added an answer in Stress:
    Why do brittle materials fail at a stress level below the theoretical cohesive stress of the material?

    fracture mechanics

    Igor L Shabalin · University of Salford

    Dear Azeez, please see "Ceramic Materials Science & Engineering (Part 3)" on my ResearchGate. A British aeronautical engineer, Alan A. Griffith just answered your question in the 1920s...

  • Chaitanya H Mehta added an answer in Scattering:
    How can I compute the fresnel zone width for finite offset source-receiver spacing for single scattering?

    I need to deduce range of receivers that would contribute to wavefield at a virtual receiver location in wavefield datuming. A paper to relate the fresnel zone width to banana-doughnut kernel (sensitive to travel time) with non-zero source-receiver offset will help a lot.

    Chaitanya H Mehta · Indian Institute of Technology Bombay

    Pl see the attached paper, " Fresnel zones and the power of stacking used in the preparation of data for AVO analysis" by John C. Bancroft, and Shuang Sun, presented in SEG 2003 conference. It gives detailed derivation of the expression you are looking for. 

  • How can we formulate Loschmidt's paradox in the quantum domain?

    This question was inspired by the answers and discussions around a previous question,

    What does Loschmidt's paradox tell us about the second law of thermodynamics? (https://www.researchgate.net/post/What_does_Loschmidts_paradox_tell_us_about_the_second_law_of_thermodynamics/3)

    Assume for simplicity a monoatomic gas closed in a container. The container walls are assumed completely reflecting and totally opaque to heat. Assume that all the atoms are identical and spherically symmetrical.

    Then the total state of the gas should be either symmetrical in all the particles (boson gas), or anti-symmetrical (fermion gas). In short, the particles are entangled, not independent. So, we can't represent the state of the gas as a product of the states of the individual particles.

    A first problem is how do we define the entropy of this gas?

    The simplest expression for the entropy is,

    S = -kB Σj pj ln pj

    where kB is the Boltzmann constant, pj is the probability that the system is in the j-th microstate, and the summation is carried over all the possible (orthonormal) microstates ψj of the system. So, if the gas is in the beginning of its evolution in some mixture of states, pj is the probability of the state ψj in this mixture.

    However, as the container is completely isolating, the gas is a completely isolated system and it evolves unitarily. The number of states remains the same all the time. So how can the entropy increase?

    Also, sometimes in discussing the paradox, people speak of reversing the evolution of the system by reversing the velocities of all the particles. But the particles are indistinguishable, s.t. under the quantum regime they loose individuality. Moreover, the indetermination in the particles' positions is as big as the dimensions of all the container. So, where is the particle whose velocity we want to reverse?

    So, bottom line, how we formulate the paradox in the quantum regime?

    Eugene F Kislyakov · Belarusian State University

    In late fiftieth L.D. Landau had said, that Hamiltonian is dead. There are a lot of problems with QM, concerning continuos spectrum.

    Agostino, and not only he, is trying to solve (or at least formulate) these problems.

    The dificulties are of principle (fundamental) order. Computing power is not the solution.



  • How do anaerobic bacteria cause bacteremia?

    I tried to find their mechanism of survival within bloodstream but I have not find much information. I could use some help in any suggested reading or some explanation of the mechanism. Thanks!

  • Purti Choudhary asked a question in Classifier:
    How to classify Brain MRI images using Decision Tree classifier??

    I have a dataset of 35 images of which 20 are used for training and 15 for testing.

    I have taken texture features for classification and MATLAB direct functions RegressinTree.fit and predict for the classification to get class results for test images.

    But I am getting very less accuracy 58%.

    What can be done???

  • Massih Afghah added an answer in Cenozoic:
    Can anyone help me with Cenozoic European paleomaps that are or can be geo-referenced?

    I need European maps for the Cenozoic that can be used in GIS to plot fossil data.

    Massih Afghah · Islamic Azad University Shiraz branch

    you can use link below:




  • Peter Carl added an answer in Climate Science:
    Do you think there is any substantial and meaningful difference between stationary stochastic processes and chaotic systems?

    It seems in the history of climate science that most scientist spoke of the climate as being stochastic, until about the mid 1980s, where a shift occurred and the climate was more described as being chaotic. Obviously, the shift reflects the wishes of climate scientist to enable prediction and mathematical capture, but it appears only wishful thinking, at best. So, as a survey, what does the RG community think about this fundamental conundrum in the Sciences?

    Peter Carl · ASWEX - Applied Water Research

    Setting all aside which is nonlinear and difficult to treat, and what either statistians or modellers who prefer deterministic (primitive or conceptual) modelling failed to properly describe in their terms, what remains are linear, statistically solvable problems. Bravo! If I lost a key in the dark, I will seek for it in the light circle of the street lamp - and probably come to the conclusion that I did not loose a key at all. Luisiana, have a look around to see that the environment we live in is full of structures that emerge from elementary rules of local interaction but can hardly be expected to exist at this level of description. If one wants to label it this way, it appears to be the "unreasonable effectiveness of mathematics in physical sciences" (Wheeler), which bears this higher level of structuring and description - among the mathematical disciplines notably number theory, which is 'unreasonably effective' in describung synchronization phenomena (low rational frequency relationships, for example, at top of the Farey tree of rational numbers). Cf. the paper of Lagarias ("number theory and dynamical systems") which I like to cite in this context.

    Concerning GCMs, they contain all the ingedients needed, but - you're certainly right in this respect - may become intractable (or at least difficult to handle) when chaotic dynamics, homoclinic or heteroclinic orbits, etc. emerge. The "solution" of fixing the srews that parameterizations offer until dynamics become tractable just leads to the problem that I have quoted (as an example) of inadequate monsoon simulation. I can demonstrate this with the "small" GCM that I have run in the past in order to better understand these dynamics (a Mintz-Arakawa GCM). I have learned a lot when using this model, even of its failures galore (instabilities) I had to struggle with. I could not have developed my conceptual view on boreal summer monsoon dynamics without experimenting with that 'old-fashioned' model. So, at least for me, it was very helpful to have such a tool near at hand (which could be run even on a 386 PC at the beginning of the 1990s).

    A nonlinear system of equations bears the corresponding linear solutions as well, and if the situation (initial and boundary conditions, parameter values) is such, it will find them - but reducing it to linearity in cancelling the nonlinear terms, you will never see the nonlinear solutions, of course, and thus perhaps come to the conclusion ... the key has not been lost :-) (my apologies). The problems I quoted of present-day large GCMs appear (to me) to be a result of "fixing the screws" until the models become tractable (an economic decision as well), and losing the interesting nonlinear dynamics this way that at least qualitatively correspond to the behaviour of mother nature.

    Kind regards,


  • Naseem Ahamed asked a question in Probit:
    Would a time series probit regression yield bad result. If yes, why?

    independence of dependent variable

  • Ying Ling added an answer in Program:
    How to caculate the AIC of GPCM,when we know the -2loglikelihood?

    I want to caculate the AIC of GPCM. From the program of Parscale, I had know the value of -2loglikelihood (namely G2 or -2ln(L)).  AIC=2k-2ln(L). k is  the number of estimated parameters of GPCM. My question is that if the scale have 8 items and each item have 5 categories, then what the k is. 

    Ying Ling · South China Normal University

    Karin Schermelleh-Engel ,

    Thanks for your answer! After reading some papers, I agree that the K is 40.  8 slope parameters, 4*8=32 threshold parameters

  • Is anyone familiar with an evolutionary approach to the perception of one´s own name?

    I need some literature, which will support my idea. Namely, that strong brain response elicited by hearing own name helped our ancestors survived "XYZ watch out the tiger behind you!". Or is it rather connected with that, that people had to know what others member of group think about them? When they knew that somebody is talking about them they could eavesdrop and know if they are accepted by the group or not. If yes, their survival was more likely, because of support from the group.

    Adriana Michalak · University of Salzburg

    I would like thank you very much for all the answers. The responses were really helpful!