ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

Browse by research topic to find out what others in your field are discussing.

Browse Topics

  • Roberto Ardovini added an answer in Mangroves:
    Any suggestion on which genus this species is?

    Collected in mangrove mud.

    From Southeast Brazil (São Paulo).

    Operculum present.

    Thank you =)

    Roberto Ardovini

    I could not see any illustration of Parodizia uruguayensis Medina , 1959 his published in a rare magazine called " Neotropica 5 (17 ) : 51-55 " . The type that you post is different from the type that is illustrated in da Silva Mendes & Veitenheimer- 2004 (seems a real Pyramidellidae), your type instead looks like a " freshwater grastropod " . " Syrnolopsidae " ???
    Do more research because it could be a species new to science.

  • Konstantin Loganovsky added an answer in Spasticity:
    Are there any controlled studies of the effects of clonazepam on cerebral palsy?

    I am writing a review article on treatments for cerebral palsy (which I have actually got). I am having great troubles finding clinical trials of controlled studies which have investigated spasticity or other measures of disability in cerebral palsy for many drugs. This hasreally surprised me because I have been prescribed tizanidine in the past and I currently take clonazepam.

    There is a lot of research that has investigated the effectiveness of tizanidine, clonazepam, dantrolene and tiagabine on spasticity in people with multiple sclerosis, spinal cord injury and post stroke spasticity, but not CP. This is a bit troubling because cerebral palsy affects a different area of the brain and different neurological/chemical pathways and I am really surprised that other review articles have recommended them but not shown any evidence of their effectiveness in CP (see attached).

    Any help would be greatly appreciated.

    + 1 more attachment

    Konstantin Loganovsky

    Dear Nicholas:

    Thank you for a good profeccional question. As you know, cerebral palsy may comorbids with epilepsy. That's clonazepam could be useful here. However, there are NO evidence-based multicenter randomised placebo-controlled clinical trials. In other words, if at cerebral palsy you would like to treat comorbid epi, please use NO benzodiazepins (like clonazepam), but rather valproates etc.

    All the best,

    Konstantin Loganovsky, MD, PhD, prof., Kiev, Ukraine

    Am J Ment Retard. 2002 Sep;107(5):376-410.
    Benzodiazepine behavioral side effects: review and implications for individuals with mental retardation.
    Kalachnik JE1, Hanzel TE, Sevenich R, Harder SR.
    Author information
    Behavioral side effects associated with benzodiazepines (such as clonazepam, diazepam, and lorazepam) are an easily overlooked and underrecognized problem with individuals who have mental retardation and can be inadvertently confused with other behavioral or psychiatric conditions. Based upon a literature review, behavioral side effects occurred for 13.0% of 446 individuals with mental retardation who were prescribed benzodiazepines for either behavioral or psychiatric conditions (n = 138, 17.4%), epilepsy (n = 208, 15.4%), or other medical conditions such as myoclonus or cerebral palsy (n = 100, 2.0%). Behavioral side effects for individual benzodiazepines for which data were available ranged from 11.4% to 25.0%. Implications of nonrecognition are discussed, and clinical indicators suggesting review by appropriate medical personnel are provided.
    [PubMed - indexed for MEDLINE]

    J Neurol Sci. 1993 Jul;117(1-2):54-60.
    Treatment of spasticity in children with low dose benzodiazepine.
    Dahlin M1, Knutsson E, Nergårdh A.
    Author information
    In an attempt to investigate whether benzodiazepines at low dosage have a significant effect in reducing spasticity among children with cerebral palsy, we carried out a double-blind, placebo-controlled, cross-over study. Twelve children with either spastic diplegia or hemiplegia participated in this study. The mean age was 14 years. The restraint of passive knee movements was determined with a dynamic dynamometer and spastic stretch reflexes were measured as EMG activity in muscles stretched. Clonazepam was given at low dosage (0.02 mg/kg body weight). In each child measurements of passive restraint were made on 2 different days immediately before and 3 h after an i.m. injection of either clonazepam or placebo in randomized order. Clonazepam significantly reduced spastic restraint (P < 0.001) compared to non-significant reduction with placebo. The mean plasma concentration of clonazepam at time of spasticity evaluation was 21 mmol/l which is in the low dose range, far below conventional doses. The study thus shows a positive effect of low dose clonazepam in reducing spasticity in children when given as a single dose.
    [PubMed - indexed for MEDLINE]

  • Pradeep Kumar added an answer in Signal Processing:
    I am using cross correlation to find time delay in sinusoidal function. It works fine with small delay.....???

    I am using cross correlation to find time delay in sinusoidal function. It works fine with small delay. However, with relatively large delay it does not give accurate answer. Please claraify my doubt.

    Pradeep Kumar

    @Fernando Soares Schlindwein

    Thanks for your answer. What is the advantage of adding filter in this case? Pls clarify.

  • Curtis L Weller added an answer in Enzymatic Assay:
    Help with a calculation of triglyceride amount in liver tissue?

    I extracted liver tissue (~100 mg) using Folch method and evaporated the solvent mixture and resuspended the lipid in 600 ul of dH2O (with triton x100). Then, I determined the concentration of triglyceride using an enzymatic assay. For this determination, I used only 4 ul from the 600 ul, and the TG concentration was 130.5 mg/dL. Now, I need to convert the amount (mg/dl) to umol/g and to mg/g?? Any help on this conversion would be greatly appreciated..

    Curtis L Weller

    (130.5 mg TG/1 dL assay sample) x (1 dL assay sample/10^5 uL assay sample) x (1 uL assay sample/4 uL resuspen soln) x (600 uL resuspen soln/100 mg liver) x (10^3 mg liver/1 g liver) = 195.75 mg TG/g liver

  • Umer Farooq added an answer in Reinforced Concrete:
    If the allowable deflection exceeds in a doubly reinforced concrete beam, how will the compression and tension blocks behave?

    How the compression and tensile stress will react in a reinforced concrete beam when the allowable deflection exceeds?

    Umer Farooq

    Dear Ariadne Tsambani. Thank you for the document. But unfortunately that doesn't answer my question. That document doesn't express anything specifically about the theory of doubly reinforced beam except design formula.

    Dear Ponkumar llango, tension occurs in a simply supported beam below the neutral axis and compression zone above neutral axis. It is obvious the cracks will be developed at the weak locations or zones of maximum shear. Will the compression  and tension zone still remain in their respective zones? How the redistribution of stresses will take place after allowable deflection exceeds in doubly reinforced beam?

  • Rudy J Richardson added an answer in Molecular Dynamics Simulation:
    Can water molecule be included as ligand in the activity pocket when making molecular dynamics simulation?

    When MD simulation, all water molecules are excluded inside protein (except binding with cofactors). Now my protein has no cofactors, but I want to know how the protein behave once water inside the pocket. However, when the beginning step of MD simulation, all water molecules are deleted. So how can I put one or two water molecules inside the pocket to make MD simulation?

    Rudy J Richardson

    Depending on the software, you can make one or more water molecules part of the protein. Alternatively, you can let the simulation run in explicit solvent and observe water entering the protein.

  • Gouravjeet Singh Ghumaan added an answer in Disruptive Technologies:
    Can smartphones in the classroom be considered disruptive technology?

    Trying to clarify educational context of disruption

    Gouravjeet Singh Ghumaan

    hello everybody.. i think smartphones find an important place in everybody's life. But use of smartphones in classroom is a an ethical issue... it is more important to inculcate values among the students, So that they can make proper use of smartphones for education. As an issue of discipline, smartphones must not be only allowed in classrooms....rest is upto the Mission, Vision and aims and objectives of institution with cultural differences....  

  • Eleni Kourtidou asked a question in Magnetic Beads:
    Magnetic beads or affinity resin for purification of IgG?

    Which technique is more preferable among magnetic beads and affinity resin?

    Are there pros and cons for each technique?

  • Munji Shanmukharao added an answer in Equity:
    Could you suggest to me, what are the tools required to calculate the impact of FIIs investment on companies equity price?

    I would like to test the relationship and impact of FIIs investment of particular company on company's equity price and also want to know the impact of FIIs investment on Stock Index. Pls suggest me, what are the statistical tools  good for conduct? I am using 10 years data.

    Thank you,

    Munji Shanmukharao

    Thank you very much for clarifying my doubt

    I grateful to you

  • Guillemette Redier asked a question in Happiness:
    How happiness can improve motivation at work ?

    Y theory and happiness at work

  • Ian Kennedy added an answer in Academic Writing:
    What is refereed/non refereed journal?
    Is it similar to peer reviewed journal? How do we categorize the seminar proceedings that are published? Are they peer reviewed books?
    Ian Kennedy

    Refereed” is the word meant here. It has a total of 2 r's and 4 e's. (“Referred” has 3 r's and 3 e's, and means 'made a reference to').

    Locate the potential journal in your library, and look through the most recent 12 months of issues. The masthead of the journal is usually in a frame near the front or the end of the journal or inside covers. It contains data such as the editors of the journal, the publisher, and the place of publication. The journal will state here that it is peer-reviewed i.e. refereed.
    There are lots of journals outside Science Citation Index that are refereed. E.g. “The English Academy Review”

    The question is also being answered at https://www.researchgate.net/post/What_is_refereed_non_refereed_journal

  • Boris Michaylovich Sharga asked a question in Glyphosate:
    What is a maximum residue level (MRLs) for glyphosate in buckwheat seeds for human consumption?

    Thank you for your answer.

  • Michel L. Marcondes added an answer in First-principles Calculations:
    How can I get accuracy optimize structure?


    I'm trying to get accuracy optimize structure, but the lattice constant is not consistent with experimental data.

    For example:

    I'm working with spinel LiMn2O4 (space group fd-3m:2), like show in attached cif file, with 56 atoms (8 atoms of Li, 16 atoms of Mn and 32 atoms of O).

    The lattice constant in this cif file is 8.2399 A, this value is consistent with value obtain by other researches.

    I'm optimizing the structure in VASP, but the lattice constant value that I got  8.0625  (not consistent).

    I'm using PAW-PBE pseudopotencials and 8x8x8 k-points grid. Bellow INCAR that I used.

    How can I get more accuracy lattice and structure?



        SYSTEM = LiMn2O4
        ENCUT = 520 #1.3 x ENMAX
        PREC = Normal
        LREAL = Auto

        EDIFF = 1E-5
        EDIFFG = -0.01
        NSW = 10

        ISMEAR = 2; SIGMA = 0.2;
        IBRION = 2
        ISIF = 3

        NCORE= 4

    #save disc space
        LWAVE = .FALSE.
        LCHARG = .FALSE.


    Michel L. Marcondes

    Hello Maximo Ramirez,

    By your INCAR file, I see you are doing volume relaxations to get the cell at zero pressure (ISIF = 3). Are you following the suggestions at section 7.6 of VASP manual?

    When you perform this kind of calculations you have problems related to Pulay stress. This may be causing this difference in your results. Follow the suggestions of the VASP manual and see if you get better results.

    In my opinion, the best way to get optimized zero pressure structures is to perform calculations in several volumes and then fit an equation of state (EoS). In your case, this is straightforward, since your cell is cubic.  The EoS is what gives you the right pressure for your system. The difference between the EoS pressure and the pressure given by VASP (that is calculated with the stress tensor) is small, but can lead to the kind of differences you are getting in your calculations. If you have already followed the steps in the manual, try to calculate the lattice parameter using the EoS method.

  • Michael Maness added an answer in Choice Modeling:
    Is Biogeme is good for Choice Modelling?

    Is Biogeme is suitable for behavioral choice models?

    Michael Maness

    I've used BIOGEME in some of my work as a graduate student and as a teaching assistant. It is well suited for many discrete choice modeling tasks. But the specific version of BIOGEME (Bison versus Python) depends on the type of model you are trying to estimate. Most of the traditional logit-based models (MNL, Nested/GEV, mixed) can be estimated with the older Bison version. The Python version allows you to specify the likelihood function yourself, so you can estimate more advanced models if needed. Also, the user group for BIOGEME is pretty friendly and quick to respond to questions.

  • Sofia Wikman added an answer in Criminal Justice:
    Is there any work which looks at the reasons for low number of women in criminal justice agencies, especially the police?

    The percentage of women in the police in US, UK and most Asian countries remains at or around 10%. Do agencies follow gender neutral policies or promote women's recruitment actively?

    Sofia Wikman

    Jeff Hearn, Wendy Parkin (2001) Gender, Sexuality and Violence in Organizations

  • Roger M. Pearlman CTA added an answer in General Relativity:
    A hot iron is heavier than a cold one, true or false?

    Why does the same object weigh more when it is hot than when it is cold?

    The reason why hot objects are heavier is because E=mc^2. If you have absolutely identical objects that have the same weight exactly when they are at same temperature, then when one object is heated, it will weigh more. This is because the gravitational force depends on the stress energy tensor in general relativity.  The stress energy tensor 00 component is the total energy of the body, which includes the rest mass plus the kinetic energy of the object. Temperature differences means that there is a different amount of kinetic energy in the motion of the atoms of the two bodies.


     How is it describable by massless photon (electromagnetic energy)?

    Roger M. Pearlman CTA

    if so why does a dead human body 'dead weight' feel heavier than if alive? 
    perhaps our soul causes a reduction in the stress energy tensor?

  • Kenan Lopcu added an answer in Econometrics:
    Why do we use the stationarity test in econometrics?

    Can you help me, why we use stationarity test to time series data? this is very complicated me. please give easy references. 

    Kenan Lopcu

    Standard tests (i.e. t, F, etc.) are valid when variables are stationary. When variables are not stationary we can not rely on these tests. For easy references start with some  undergraduate  econometrics books which includes basic time series methods (i.e. Gujarati). You can also look at Enders, Applied Econometric Time Series Methods,  as a more advadced reference. 

  • Alham Walid added an answer in Climate Data:
    What is the best data center to download any country or city climatic data?

    I am looking for a data center that provides freely available daily climatic data (mainly precipitation and temperature) for Jordan and Syria. I need past observed data up to now that is manipulated, and if these could be downloadable , the higher the resolution would be the the better . Thanks for any suggestions.

    Alham Walid

    Thank you all so much 
    I will check them out 


  • Monsumee Alam added an answer in Anti-Diabetic Drug Design and Discovery:
    Low cost evaluation of in vitro anti-diabetic compounds
    I want to study antidiabetic activities of some new chemical entities. Can you suggest an in vitro method or KIT that would be easily available in India?
    Monsumee Alam

    i am also searching for the same. please let me know if you get any link

  • Tatiana Beketova added an answer in Therapy:
    What's your experience in Rheumatoid Vasculitis and biologics?

    Standard therapy for rheumatoid vasculitis is corticosteroid pulse therapy or cyclophosphamide. And what about a better control of RA with biologics? And about the risk of vasculitis with anti-TNFalfa drugs?

    Tatiana Beketova


  • Song Ge asked a question in PXRD:
    Is it possible to get exactly the same PXRD pattern for different perovskites?

    I'm doing synthesis with perovskites, Sr2CrFeO6 and La2NiTiO6. As the PXRD database (we use the EVA database) failed to produce satisfying reference patterns, I plotted both material unit cells in VESTA, both with the space group I 4/m, and used that to calculate a theoretical PXRD pattern (using Mercury). But the patterns turned out having exactly the same peaks. Does anyone know what may have gone wrong with my calculation method, or this is actually a possibility? I would assume that even with the same type of unit cell, because the atom sizes etc. are vastly different the PXRD would be different.

    Also would appreciate it if anyone has PXRD information on either of these two perovskites.

  • Virendra Kumar Saxena added an answer in Soil Science:
    Can anyone explain me how to determine actual concentration of As in digested soil sample, considering DF, WF, CF and VF ?

    If I use 0.5 g soil + 9 ml HNO3 + 3 ml HCI for microwave digestion. And I take only 5 ml of supertant from this digest and dilute it to 25 ml, by adding 5 ml of 5 % KI and 5 % ascorbic acid for decreasing of As (V) to As (III) and the rest (15 ml) distilled water. 

    What would be my WF, VF, CF and DF?

    I know that : Actual Conc. = Conc.* VF * DF * (CF/WF)

    for AAS, however I am confusing WF,VF,CF,DF during calculation. 

    Virendra Kumar Saxena

    ICP-MS is one of the best tool for determining the As in digested soil sample.

  • Ramana K v added an answer in Online Journalism:
    What is your opinion about recent decision of medical council of India to consider Index Copernicus as acceptable?

    This is what medical council of India's circular says






    a. Index agencies: Scopus, PubMed, Medline,

    Embase/Excerpta Medica, Index Medicus and

    Index Copernicus

    b. Types of articles to be considered: Original

    research articles and original research papers.

    c. Criteria for National/International journal:

    Published by a National/International –

    specialty journal/journal of a national/

    international society provided it is included in

    one of the indexes mentioned above.

    d. Authorship: First author, second author

    e. E-journals: E-journals not included

    Ramana K v

    Yes I have gone through that editorial. I request your opinion

  • Eleni Kourtidou added an answer in Agilent:
    MSD Check Tune failed. Does anybody have an idea about the reason?

    I work on an Agilent LC/MS system with the Agilent 6120B Single Quadrupole mass detector in ESI positive mode. I have tuned the instrument (in Autotune mode) with Agilent ESI Tuning Mix. However, just few days after tuning and after runnning a quite small amount of samples (inconsiderable), the Check tune always fails. This happend again in the past, so I really need your opinion why is this happening. What do you suggest me to check?

    Eleni Kourtidou

    Mrs. @Michelle R Peace I attache the last MSD check tune file in posititve mode, in order to answer to your question about what failed. Please note tha the instrument is pretty new. 

  • Abrar Hussain added an answer in Acoustic Signal Processing:
    Source separation of similar known sources shape?


    I'm wondering if there's some work in source separation where the sources shape is known, and where all the sources share the same shape but with different location, therefore the mixtures follow an anechoic form.

    • mi = \sum_ j(aijSj(t-tij))
    Abrar Hussain

     Your question is not clear! take a look on this though!

  • Monineath EL asked a question in Export:
    How can i calculate or obtain Processing exports from total export (by Harmonization System)?

    I have obtain raw data of total export (by Harmonization System) classified in products, however, i want to know how can i obtain processing export from these data. As in the model, it's required processing export. Thanks.

  • W. Porzio added an answer in Polymethyl Methacrylate:
    What solvent is used to make PMMA coating on glass fiber ?

     I have checked many questions posted earlier they have mentioned solvent such as toluene, acetone  etc. Main requirement for me is the refractive index of coated PMMA should be same as before solid state (before application to solvent). kindly help me

    W. Porzio

    I completely agree with the suggestions of Varun. The only further thing to take into account is that fiber glass displays poor affinity with organic solvents so oxygen containing solvents should be preferred 

  • Jennifer Gibbons added an answer in shRNA:
    How to test siRNA or shRNA silence efficiency toward PD-1?

    I want to test siRNA or shRNA silence efficiency toward PD-1 in whatever cell lines, just to make sure that our siRNA sequence works. Which way is the easiest, WB, FACS or qRTPCR? which cell line should be used that produce much PD1? Can IFNγ stimulate T cell line to produce more PD1 which is just good to be used? Can I transduce virus to stimulate PD1 level, and then silence it? Thank you

    Jennifer Gibbons

    WB or qPCR both work- the ease depends on whether you have antibodies or primers to your protein of interest. ;) Knockdown by qPCR can be difficult to identify, as the Ct changes can be within variablility of the instrument (2-fold = 1Ct, the error range of the instrument). If you use qPCR, have a few replicates.

  • Niranjan M added an answer in Spores:
    Does anyone know of this ascospores?

    Does anyone know of this ascospores?

    Niranjan M

    Yes sir these are ascospores, deliquescent asci oosed out the spores which are dispersed,

  • Johannes Heekerens asked a question in Well-Being At Work:
    Can I conduct a mediation analysis with two variabels measuring the same construct (baseline/follow-up) and a mediator (post intervention)?

    My aim is to investigate why an intervention known to increase well-being works. I identified a plausible moderator variabel and currently plan a longitudinal study to test my hypotheses.

    My question is: do I need an experimental design in order to create variance and a predictor variable? group --> intervention yes/no --> mediator post --> well-being follow-up

    Or is it possible to conduct a mediation analysis without a control group? well-being baseline --> intervention --> mediator post --> well-being follow-up

    Thanks for your ideas, I'm really stuck here ...