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  • Daniel Albrecht added an answer in Benzodiazepines:
    Do commonly prescribed benziodiazepines bind appreciably to the 18kDa Translocator Protein (TSPO)?

    I'm conducting a human imaging study with [11C]PBR28, a TPSO PET ligand, and am considering including subjects who are prescribed benzodiazepine medications. I am familiar with the 2013 Synapse publication by Kalk et al. that analyzed binding affinities of several benzos to TSPO in post-mortem human brains, but unfortunately they compared a limited range of benzodiazepines. I was wondering if anyone knew of any additional information or studies that included a larger range of benzos (e.g. alprazolam). Thanks!

    Daniel Albrecht

    Thanks, Beatrice! I've seen a number of these but I'll give them a more detailed read.

  • Aram Soroushian added an answer in Damping:
    Does there exist any general rule for the influence of damping on the numerical stability of time integration methods?

    Dear all, in time integration analysis of semi-discretized equations of motion by explicit methods, such as central different and linear acceleration, the maximum time step size guaranteeing numerical stability increases when the physical damping is increased. I am interested to know whether there exists any general rule with theoretical support in this regard for arbitrary time integration method. To say better, in a slightly generalized manner, is their any rigorous mathematical explanation that for arbitrary time integration method the stability critical time step has its smallest value when the damping is zero? Many thanks for your kind patience and attention.

    Aram Soroushian

    Dear Jean Phillippe

    Many thanks for your kind attention and nice contribution and the book. Hopefully, towards a response soon. Have a nice day, and nicer future.

  • Emadeldin M Kamel asked a question in Gromacs:
    Which is better in running molecular dynamics simulation; Amber, Charmm or gromacs?

    which one is the easiest and most accurate

  • Giancarlo no middle name Ruggieri added an answer in Chronic Renal Failure:
    What is the novel specific marker for chronic renal failure?

    i want a specific marker for determination of chronic renal failure

    Giancarlo no middle name Ruggieri

    I have to go on along the previous reply to Dr Barack Nieto , because my intervention was interrupted by a my erroneous digitalization  during the reply. I had to add that if the onset of renal disease is without any sign  it could obviously impossible to think the there is a condition of disease. But I have to remind that a different clinical sign  could be simultaneously  present, and possibly signaling the presence of  a renal disease in absence of any modification of laboratory data, and this is the presence of an  hypertension :  it is on the responsibility  of who diagnoses as  essential hypertension an hypertensive  condition without having  accurately explored any possible cause of a secondary hypertension, and in the particular  case cited by Dr Barack Nieto probably could be of help the study of the intra renal vascular  resistance and eventually the isotope exact definition of glomerular filtration rate.and renal plasma flow.            

  • Andrzej Lasia added an answer in Potentiostat:
    Why is the voltammogram jumped up at low scan rates?

    It never happened to me before. The whole Pt voltammogram shifted up on the current scale at 20mVsec-1 and lower scan rates. Im using bio-logic potentiostat and microcell with 0.5MH2SO4 electrolyte.

    Andrzej Lasia

    Try to run CVs at the same constant scale, i.e. the same svale for different scan rates (do not use autoscale). You should also use "analog sweep" not the staircase sweep (which eliminates part of the (pseudo)capacitive current).

  • Ifigeneia Metaxa added an answer in Ultrasonication:
    What are various well known ultrasonic processors used for ultrasonication of nanofluids??

    I would like to know about the experiences and views about different ultrasonic processors used by various researchers for nanofluid sonication. There are many ultrasonic processors available in the market but i am not sure how to pick one and i don't want to take a chance by randomly buying one since they are very expensive and the money is funded by the state.

    So i will be extremely grateful if someone can share his/her experiences or recommend me the name of a  good ultrasonic processor making company!

    Thank you very much!

    Ifigeneia Metaxa

    You could take a look at Bandelin. We were happy with their product. 

  • Ranjith kumar Rajendran added an answer in Fungal Biomass:
    What are the methods used for the preparation of fungal biomass for biodegradation studies?

    I would like to prepare filamentous fungal biomass (Fusarium solani) to get a mycelium for biodegradation experiment. If anybody suggest me, would be useful.

    Thanks in advance

    Ranjith kumar Rajendran

    Thanks a lot Prof..Ana Maria Anselmo for your E.Mail

  • Sandhyaa Subramanian added an answer in Lysis Buffer:
    Why am I getting insignificant TEV cleavage and protein degradation?

    I am purifying a small soluble protein with -His tag using 50mM Tris, 300mM NaCl as lysis buffer. I add PMSF and protease inihibitor cocktail during cell lysis. After elution and desalting in 50mM Tris for TEV cleavage of the -His tag I find that my protein degrades after 1.5 days without any significant cleavage at room temperature (about 25 degrees celsius). My -His tag is accessible (since it binds NiNTA column) and I use high concentration of TEV. The degradation is evident since I do not find a band at the desired molecular weight after SDS PAGE.I even ran SDS-PAGE for the precipitate that was present but the protein was not there - instead a series of low and high molecular weight bands were present. Please help. Thank you

    Sandhyaa Subramanian

    Thank you for the suggestions. @Marcia Moss: I carried out cleavage at 4 degrees too. Though my protein did not degrade there was no TEV cleavage.  My tag is in the C-terminus which has about 7 amino acids in the disordered region. Will that affect TEV cleavage? 

  • Christian Q. Scheckhuber added an answer in Blots:
    Why there is nothing in Loading control but Protein specific signal at the right size?

    Running a 10-20% Tris-Tricine blot with nuclear and cytoplasmic fraction of cell lines transfected with 4 different expression constructs.

    Got desired protein bands (9 kd) for two constructs in right size with protein specific antibody but strangely no bands found for loading control either in cyto or nuclear fraction but found bands for tubulin and Lamin B for the other two expression constructs .

    How I am getting nice bands for the protein of my interest but nothing in the control lane?

    What could be the explanation for this situation or what should I change?

    I followed the abcam nuclear fraction protocol.

    Christian Q. Scheckhuber

    Which protein do you detect as a loading control? Maybe the antibody for this protein is not working anymore... If possible use a fresh antibody aliquot.

    Cheers, Christian

  • Sabiya Abbas added an answer in Glutaraldehyde:
    How do I store samples after the dehydration step in human cartilage histology?

    Hi, I am using a histology protocol to look at the structure of human cartilage samples. I fix the samples in 4% PFA or 10% NBF for 48 hours, decalcify in 0.5N HCl / 0.1% Glutaraldehyde 48 hours  and dehydrate in 75%, 95%, and 100% ethanol.This step takes about 14 hours and will not be able to finish it in a day. I was wondering how can  I store the samples after this stage prior to infiltration step. Can I store them in 70% or 100% ethanol over night in the fridge?

    Also is de-paraffinising step the same for animal and human cartilage samples?

    Thank you. 


    Sabiya Abbas

    After dehydration u can store samples in 70% ethanol  at 4 degree for three days.  

  • Farhan A. Larik added an answer in Induction Machine (IM):
    Can anyone help me with the induction generator model I have attached below?

    i want to connect the math function block( used for squaring the stator current) with resistor (as in in the picture below )but i am unable to connect it with resistor... plz modify the model as far as u can plz...


    + 1 more attachment

    Farhan A. Larik

    thanx dear.

  • Robert James McClelland added an answer in Linear Mixed Models:
    How can I calculate effect size and 95% CI in linear mixed models in SPSS?

    I obtain the estimate and its 95% CI, and the F, df, t, SE values for fixed continuous effects. Is it possible to calculete the R2 from these values? Thank you.

    Robert James McClelland


    Lee Becker covers this well in his site (sections 3,4,5,6,7.......)


  • Osman Doluca added an answer in Quantification:
    Can somebody provide me with a valid protocol to quantify Ethidium bromide by mean UV/HPLC ?

    Hello every one

    I need to quantify EtBr in aqueous solution with expected concentration lesser than 0.5 microgram/ml. I have a UV/HPLC in my lab but I can not find a trusted protocol to perform the EtBr quantification .

    I will be grateful for any help.

    Osman Doluca

    Use Beer-Lambert Law and extinction coefficient (ex.cof.) of EtBr in water ( E480 nm = 5450 1/M*cm (a))

    Prepare a solution of EtOH. Use UV to measure its ABS at 480 nm. Do not forget to use distilled water or buffer as blank. if the ABS is higher than 3 dilute it 10 times. If it is still above 3 dilute again until you get a ABS below 3 and above 0.1. Than use Beer-lambert Law: C=Abs/(ex.cof.*width of vessel)*1/(dilution). 

    For instance, if you get an absorbance of 1.5 after diluting 10 times using 1cm wide vessel your concentration will be: c=1.5/(5450*1)*1/10= 2.75 * 10^-5 M = 27.5 uM

    (a) Saucier, J. M., Festy, B. & LePecq, J.-B. (1971) Biochimie 53, 973-980.

  • Frank Emmert asked a question in Antitrust:
    Can Anyone Recommend Articles or Materials on the Dispute over Offshore Gas in the Levant Basin?

    I am researching the position of the different countries with interest in the huge gas deposits in the Levant Baisin, in particular Israel, Lebanon, Syria, and Cyprus.

    I am interested in legal, political, and economic analysis of the rights and obligations of the different countries. I am also interested in sub-national and private actors, for example the antitrust case in Israel, etc.

    Thank you in advance!

  • Rachel Gill asked a question in Behavior Therapy:
    What are your statistical recommendations for an RCT comparing a treatment to waitlist control group using a self-reported, pre-test/post-test?

    I am currently conducting an RCT testing the feasibility of an online dialectical behavior therapy skills training program. I have 42 participants.  21 are randomly assigned to the experimental condition and 21 to the wait-list control group.

    I am using a pre-test/post-test strategy that employs the Difficulties in Emotion Regulation Scale (DERS) and am wondering what you think the best statistical strategy may be for analyzing differences in resultant DERS scores. Post-test response rate percentages for both study groups are expected to be between 25 and 75 percent.

  • Wiep Klaas Smits added an answer in Antibiotics:
    Why is cation adjusted Mueller Hinton Broth used? How do Mg and Ca cations interfere with the activity of certain antibiotics?

    Why is cation adjusted Mueller Hinton Broth used? How do Mg and Ca cations interfere with the activity of certain antibiotics?

    Wiep Klaas Smits

    http://www.drugbank.ca/drugs/DB00080 at least part seems to be dependent on a Calcium dependent membrane insertion mechanism.

  • Maciej Florczyk asked a question in DNA Fragmentation:
    Could you take a look at those DNA fragmentation assay results?

    The image shows DNA fragmentation assay of cells treated with toxin. I'm not sure how to read those results. For sure there is fragmentation in well with number 1, but what about wells 2 and 3? Does anyone know what this smear could mean?

  • Thierry De Mees added an answer in Dark Matter:
    What is the formula for spin independent elastic cross section of dark matter particle scattering off a nucleus?

    Recently I have been trying to calculate the spin independent scattering cross section for direct search of dark matter for a particular dark matter model. I came across several papers where the formula is given. In some cases the formula is given for NUCLEUS and in some cases for NUCLEON. And at the same time in some papers there is a reduced mass term [arXiv:hep-ph/0307185] and in some cases it is tad different [Prog. Theor. Phys. 126, 435,(2011)]. I need spin independent cross section calculated per nucleon basis. 

    Thierry De Mees

    @ George: I am glad that you don't insist any more that a null mass would possibly get a gravity accereration. At least it is a beginning! But now you mix observation with obsolete theory interpretations. And you now dismiss SR and QM, who say that the rest mass of light is zero.

    Kirchoff's Law : you are missing the point, again.

    "Top down" structure growth: a concept, without any reasonable ground that would be based upon observation.

    In reality, a galaxy starts to become a disk from the center to the outer part. Not the opposite. You need a spinning center before you get a flattening. The same for clusters.

    Top-down fragmentation from clusters to galaxies isn't possible, but gigantic nebulae may become fragmented into galaxies, and then form clusters of galaxies.

    But this has still nothing to do with any "dark matter".

  • Fitsum Feyissa added an answer in Cold Rolling:
    How can we possibly measure and determine dislocation density using EBSD?

    How can possibly measure and determine dislocation density using EBSD. How can we measured total length of dislocation density for cold rolled metals?

    Fitsum Feyissa

    Thank you @Volker and David

  • Joseph C Pearson added an answer in Basic Bioinformatics:
    What is the best way to define promoter targets of two (or more) different transcription factors?

    Hi there,

    I'm performing some (very basic) bioinformatic analysis of our gene of interest, part of which is looking at the different transcription factors that may regulate it using the ENCODE Regulation track on the UCSC Genome Browser.

    One particular question I'm interested in asking is: what promoters in human cells bind the same set of transcription factors as my GoI?  In more specific language, which genes in the genome have a strong ChIP signal for two (or more) defined transcription factors within, say, 3kb upstream of their transcriptional start site.

    I'm very new to this kind of whole-genome dataset analysis and as a result am a near-novice; any advice anyone could give on how to do this kind of analysis in a reasonable time would be greatly appreciated! 

    I'm expecting to need to download various genome viewer(s) and or datasets etc., but at largely at sea regarding: a) what best to use for this and b) the method/approach or coding required to e.gh. define the TSS distance and the requirement for double-positive ChIP signals is beyond me. 

    Alternatively, if there is a useful programme/took/database for this  that I am unaware of, please do let me know!

    Thanks in advance for all help!

    Joseph C Pearson

    Bedtools is a command-line suite of tools (in a single program). http://bedtools.readthedocs.org/en/latest/

    Depending on your comfort with Unix-type "make" command, you can install it locally. Alternatively, your institution may have a shared computing resource (e.g. a research computing cluster) that may have it pre-installed. Thirdly, you can use the tools at www.usegalaxy.org. To start, I'd probably recommend the third option, since their video tutorials are pretty fantastic.

    Depending on your organism, you can find pre-computed coordinates for all promoters (usually defined as the region immediately adjacent to predicted transcription start sites). Relatively simple command-line tools can adjust the width of the interval, for example, using Awk. For example, from an annotation file (GFF or BED), you would just start at the first nucleotide of each gene, subtract 3000 bases if the gene is forward orientation, or add 3000 if the gene is reverse orientation. Now that I think about it, you could easily do this in Excel.

    If you are going to be doing a fair amount of bioinformatics in the future, you might want to start learning biopython or Bioconductor (in R). I just completed the coursera "Bioconductor for Genomic Data Science" course (the free, non-signature track version), and there are ways to do everything that you described, in Bioconductor. The problem is, you first need to learn lots about Bioconductor...

    I hope this is helpful!

  • Steen Gimsing added an answer in Presbycusis:
    Anyone familiar with unacceptability of frequency lowering hearing aids in clinical setup ?

    Though presbycusis is the most common type of hearing loss, frequency lowering hearing aids are very rarely used. What are the reason behind this?

    Steen Gimsing

    Thank your for your comment, Anthony.

    The evidence is introspective and anecdotical; I do not think that there is any real scientific evidence

    But in 1985 I suddenly - during a week end - got a low frequency hearing loss (about 30 dB at 125, 250 and 500 Hz, it turned out) in my left ear and the feeling of fullness in the ear. At the same time I got tinnitus in the ear  - a tinnitus that is constant and that does not bother me at  all . I can hear it whenever I want to and I can "shut it off" at will by simply ignoring it. As far as the hearing loss was concerned I first thought that it was impacted cerumen. Back in the department  the following monday I got and audiogram taken. As the hearing loss was a nuisance I fitted myself with a behind the ear air. The effect was stunning: The feeling of hearing loss and fullness vanished as long as I wore the aid. The tinnitus was also masked. During the following  year or so the hearing loss and the feeling  of fullness were extremely fluctuating: Sometimes the symptoms were gone completely; sometimes they reappeared for a couple of days. Eventually my hearing returned to normal and the fullness disappeared. But the tinnitus has remained ever since. I never had vertigo spells -- so the Meniere diagnosis is, strictly speaking, not correct: It was endolymphatic hydrops. I noticed  that the feeling of fullness and the drop of hearing could be provoked by even a small amount of alcohol  - just one glass of white wine, for instance.

    During the following decades  my career placed my in the very first line  --  in the meaning of contact with an unselected patient clientele -- of the public hearing health care seeing patients all the time with an audiogram and a case history available in every single case. In the process it amounted to somewhere around 75.000 patients.  Occasionally   --  very occasionally  --  a patient could report the same as I myself  had experienced.       So, it does occur, but the patients in question are rare birds.   Despite,  it should  be fairly straightforward to investigate this in a proper scientific way.



  • Satishkumar Tekale added an answer in Natural Product Research:
    Are the bioactive molecules from plants grown in arid regions different from the plants grown in temperate region?

    There are numerous bioactives reported from plants in literature. However, there is no clear comparison between the ones derived from plants growing in arid region compared to ones derived from plants growing in temperate region. Can anyone give in some comments.

    Satishkumar Tekale

    Yes, plant changes metabolites according to defense mechanism.in temp region secondary metabolites are  somewhat different than arid region.

  • Ajeet Kumar added an answer in Capacitance:
    How a capacitive generator output voltage's shape could be like?

    I am making a capacitive generator. When I bend that, its peak shape of output voltage was a spike. The voltage can not be maintained when I keep the generator bending. My question is what the shape of output voltage should be like when i bend a capacitive generator repeatedly, spike or square shape? 

    Ajeet Kumar

    I think you are using a piezoelectric generator. At the time of bending or applying or removing mechanical force, material will show a voltage response. The voltages generated through bending have shape of spikes in both +ve and –ve direction. This voltage can be smoothened by using extra capacitor.

  • Mohamed El Naschie added an answer in Quantum Physics:
    Why has the classical electron radius generally been rejected in quantum physics?

    There is a very close and accurate agreement between the classical electron radius, alpha, the electron Compton wavelength and the Bohr radius. such that:

    re = alpha. lambdae /2pi = alpha2 a0

    Given the great accuracy ascribed to alpha in particular, this would suggest that the classical electron  radius is valid.  

    Mohamed El Naschie


  • Stephen Scaysbrook asked a question in Building Automation:
    I am looking for research and papers on Building automation and the use of IFC 3D files ?

    I am having trouble finding information on the use of a 3D IFC file within a building Automation program, there seems to be no program that can interrogate a 3D file 

  • Matthew Hall added an answer in Sign Language:
    Does anyone know of research going on about deaf babies (0-7 months old) with hearing parents given access to sign language by deaf adults?

    Any sign language will be interesting.

    Matthew Hall

    What kind of outcomes are you interested in?   The only work I know of deals with older children. 

  • Francisco R. Lima Junior added an answer in ANFIS:
    What can I do to reduce the mean square error in anfis?

    Currently i am using the dataset (https://www.researchgate.net/publication/281449157_USDvINR_rate) to predict the future rate of INR against USD. The current training and testing mean square error are in the range of 0.0201 to 0.0235. The training set uses 5670 and test set uses 1170 random records from the dataset. What can be done to reduce the MSE further (approx 0.0001 to 0.0005)

    For further info about the implementation refer to - https://www.researchgate.net/publication/280698216_FOREX_rate_prediction_using_a_Hybrid_System

    + 1 more attachment

    Francisco R. Lima Junior

    I suggest increase the number of epochs and decrease the number of membership functions of the input variables.

  • Diogo Fonseca-Pereira added an answer in Viral Transduction:
    Which viral transduction method works for GPF-labeling of T cells?

    APC/T cells isolated from MOG-immunized mice. During in vitro activation and expansion, I would like to transduce T cells with GFP-encoding virus. 

    How can I stably express GFP in T cells for in-vivo imaging?

    Diogo Fonseca-Pereira

    HI Sophia

    In our lab we used  the retroviral transduction with a pMig-GFP vector and I could see Marked T cells at least after 8 weeks (not sure for long term experiments)

  • Abiola Etti added an answer in Healthcare:
    How can we identify patients vulnerability in healthcare practice?

    I am aiming to explore the concept of  vulnerability and the elderly in healthcare settings.

    Conceptual frameworks:

    related literatures on vulnerability, elderly, healthcare practice.

    Abiola Etti

    thank you every one for your contribution. it really helped my work. kindly view my recent question if it is your area of interest.