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  • Stefano Marchesi added an answer in shRNA:
    Does anyone have experience with lenitiviral shRNA in naive/effector T cells? Does it work?

    We are currently using lentiviral overexpression of genes of interest in T cells and this is working quite well. As a next step we would like to use shRNA to knock down gene expression. Did anyone try this already in human primary T cells?

    Stefano Marchesi

    To bypass the issue raised by Pascale, I would suggest to use a lentiviral construct with a reporter gene (such as GFP, RFP or whatever you prefer). Thus, you could easily positively select (by sorting) the transduced cells and therefore obtain a more homogeneous population. To have a good transduction efficiency, you obviously need a high viral titer and a "high quality" vector to express your shRNA of interest. For instance, updated versions of the pLKO backbone are okay. I would also suggest to activate cells during transduction, to "open" the chromatin (to make them receptive to transduction) and induce proliferation.

  • Christian Walloth added an answer in Landscape Urbanism:
    Are there any suggestions for publications based on understanding of traditional urban fabric or urban form?

    I want to study elements of urban form especially in our old settlements and their relevance. Any book or articles you would suggest?

    Christian Walloth

    Mani, If you want to learn about "urban elements" used in traditional cities around the world, you may want to have a look at the writings of Christopher Alexander, in particular: A pattern language, but also the four volumes of his magnum opus, The Nature of Order. These books offer tools to understand your cities, i.e., to determine your own point of view—the other books mentioned so far contain particular interpretations of urban development, i.e., they will potentially bias your viewpoint.

  • Alexandre Obert asked a question in Ocular:
    What is the better way to deal with ocular artifacts on ERPlab ?

    I'm recently working with ERPlab and I'm looking for the best way to deal with ocular artifacts (I'm definitively not an expert...).

    I have two EOG : one at the canthus the other below the same eye. I saw that there is several solutions through artifact detection : step-like, moving window, voltage threshold, etc...My first idea was to use step-like and/or moving window but I don't know if it's the best way ?

    I also wonder if I should perform any channel operation with my EOG electrodes or not ? 

    Any idea/Advice ?

  • Marc Stein added an answer in Disaster Planning:
    How do I plan disaster mitigation for the physical disabled?

    i want to do a research about planning mitigation for disabilities, especially for physical disability. I want to know the needs or the facilities for them during disaster

    Thankyou :D

    Marc Stein

    Hi Adiba,

    following information could also be helpful to you


    I think there's still a lot of work concerning this topic! 


  • Catalin Lazar asked a question in Social and Cultural Anthropology:
    Does anybody know Lithoglyphus pygmaeus specimens (or ornaments manufactured from this gastropod) discovered in prehistoric sites?

    Does anybody know Lithoglyphus pygmaeus specimens (or ornaments manufactured from this gastropod) discovered in prehistoric sites?

  • Tomasz Kozieł added an answer in Bulk Metallic Glasses:
    How can I make CuZr bulk metallic glass by suction casting in the form of thin foil(sheet)?

    How can I make CuZr bulk metallic glass by suction casting in the form of thin foil(sheet)?

    Tomasz Kozieł

    Dear Akanksha,

    Suction casting is usually used in order to obtain glassy alloys in form of rods. It is possible to obtain thin sections in this method, but I would say that 1-1.5 mm is minimum thickness. In order to get thinner alloys, melt spinning method is the best. 

    To compare - in the melt spinning method the cooling rate is in a range of 10^5 - 10^6 K/s, while in the suction casting the minimum axial cooling rate for 3 mm diameters is about 200 K/s. It means that a critical cooling rate of an alloy for glass formation must be lower than cooling rate attainable in a specific casting method.

    Good luck


  • Maurizio Francesco Brivio added an answer in Hemocytes:
    How can I prepare Hemocyte Lysate Supernatant?

    it is for proPO studies

    Maurizio Francesco Brivio

    There are several methods, but You can simply homogenize the cells in a Potter, in a buffer, then You can centrifugate, discard the pellleted material and recover the superrnatant.

  • Krishnan Umachandran added an answer in Marketing Research:
    What are the most common segmentation bases in health organizations?

    the most important segmentation variables for health services

    Krishnan Umachandran

    Identify the intended users based on epidemiology (who is affected?), demographics, behavior, culture, and attitude. This is known as segmentation

  • Kirk A. Fraser added an answer in Welding:
    Why does the maximum temperature decreases in longitudinal direction during friction stir welding with increasing traverse speed?

    Hi all, recently I am doing exclusive analysis of heat transfer in friction stir welded aluminium 6061 plates. Unlike the conventional arc or submerged arc welding where a point heat source is applied and while welding , the thermocouples placed in the longitudinal direction within the same reference line shows same peak temperature for all the monitoring point, the case is not same in FSW. For a lower traverse speed at a constant rpm, the thermocouples placed in any reference line in longitudinal direction of welding always shows an increase in peak temperature. Where as on increasing the speed, the peak temperature surprisingly decreases. What can be the phenomenon behind this underlying physics? I am attaching two temp-time plots for 800 rpm, 1 mm/s and 800 rpm, 5 mm/s

    + 1 more attachment

    Kirk A. Fraser


    Can you give a bit more information about your experiment:

    - Plunge rate?

    - Dwell time?

    - How long is your weld?

    - How thick are your plates?

    - The longitudinal and transverse location of each thermocouple (take the origin at the center of the two plates at the axis of the tool during plunge. A little sketch would be best.

    I ask because; we can see that TC6 and 7 must not be on the same longitudinal line as TC1-5. Also, in the first graph (800rpm,1mm/s), TC4 is inconsistent. In the second graph (800rpm, 5mm/s) TC2 is inconsistent.

    If TC6 and 7 are indeed on the same longitudinal line, they are not providing the correct signal I would think.

  • Tariq O Salim added an answer in Special Functions:
    I am working on "Extensions of Special functions and their applications ". Is anyone interested in collaboration then they are most well come?

    Since last 15 years, I am working on Special Functions and their applications. Recently, number of applications of special functions found in many fields. Now, I am interested in extensions of special functions? 

    Tariq O Salim

    Dear Prof. Agarwal

    I am interested in fractional extensions of some special functions specially orthogonal polynomials, also I do research in generalisations of Mittag-Leffler functions and applications to fractional calculus operators

  • Sibnarayan Datta added an answer in SYBR Green:
    What do "undetermined" CT values means in q-PCR?

    I am measuring the gene expression of my two target genes for Japanese flounder namely CDO and CSD. I used 1ug of RNA to make cDNA. I took 1ul of cDNA to be used for RT-PCR and run it on gel electrophoresis. Most of the samples shows strong bands but there are one to two samples with weak bands. After confirming the presence of bands, I used my cDNA for Q-PCR. I am using SYBR GREEN for my q-PCR. I did not do dilution and used 2ul of my cDNA samples in running q-PCR.

    The CT value for beta actin is around 22-32 and CT value for for CDO is 28-36 with some samples "undetermined". But for all my CSD genes, I got all "undetermined" CT values. 

    I would like to know if this has something to do with the concentration of my cDNA? Since I checked my primer using RT-PCR and got bands but when using the primer for q-PCR I cannot get a good result. 

    In addition, I tried diluting my cDNA samples 5x, 10x and 15x but still I get "undetermined" CT values. Can I add up to 5ul of my samples in running q-PCR?

    + 1 more attachment

    Sibnarayan Datta

    One more thing, from your result sheet, it appears that all the samples are same (sample 1). however the Ct values vary greatly from 28 to 36. If all the reactions are replicates of the same sample, then this indicates pipetting error. You also need to fix this problem.

  • Yoshinori Shiozawa added an answer in Rationality:
    How do the economists define self-interest and rationality?

    How do the economists define self-interest and rationality so as to make these concepts different from the animal instincts, beast behaviour, and barbarism? What is that which forms and what is that which does not form the self-interest? Moreover, are these the behavioural guides for all individuals? Are these the collective guides for policy making? 

    Given the propensity for free riding in each economic-beast, does not the collective policy results into a collective free riding of those who make policies over those who do not?

    Yoshinori Shiozawa

    Re: Guy Jakeman's question (in the 115th post) 

    I don't think there is any little thing which shows you the post number. This is one of the trick I want to demand to the administrators of the ResearchGate. I counted the number at each page and it is quite possible that I am making a mistake or mistakes.

  • Amir Hooshiar added an answer in Rubber:
    How can I reduce bouncing of a component in Transient Structural ANSYS Workbench study?

    I am preparing a study for a rubber sheet that is driven horizontally with a constant velocity against a cylindrical surface, where the rubber sheet is loaded with a constant vertical force. My aim is to study the frictional contact between both bodies.

    The solution shows that the rubber sheet bounces up and down (refer to attached snapshot for equivalent stress behavior against study time) during the solution time interval (0.02 seconds), where it gets separated from the cylindrical surface.
    How can I adjust the model settings to have the rubber sheet moving horizontally without going up and down? Please advise.

    NB: I tried to vary stabilization factor in the contact window but that was in vain.

    Amir Hooshiar

    Hi Gerges, 

    I would suggest in order to identify the origin of this behavior, you may make a coarser/finer mesh, increase/decrease belt speed, change the material properties of belt and roller...

    These would help you identify the potential origins.

    Please note that reducing the speed enables you to run for a longer time span with less length in belt.

    Good luck

  • Muthukumaran Thangaramanujam added an answer in Hand:
    Does anyone have experience with SaeboFlex?

    Does anyone have experience with SaeboFlex in neurological hand treatment?

  • Michał Stępień added an answer in Soil Organic Carbon:
    How do I convert organic carbon (%) of soil for value & interpretation into available nitrogen (Kg/Ha) & rating?

    Say in my area soil organic carbon measured is 0.28, 0.30, 0.18 %

    as per soil fertility rating it is low in organic carbon or low in nitrogen (Kg/Ha)

    now for all my data like above I want to convert into available nitrogen (Kg/Ha)

    so what will be any formulae ?

    Michał Stępień

    The issue is very complex, it depends, above all on the C:N ratio in soil organic matter, on microbial activity (it is supposed to be very low in soil with so low organic carbon content) and certainly on current soil moisture (and temperature).

    I think in temperate zone (Europe) it is considered, that about 1-2% of total N in soil is mineralized per year. In this case we can estimate the quantity of N being transformed from inorganic to organic form (assuming the C:N ratio of 10:1) in following way:

    1) calculation of volume of soil in accumulation layer;

    2) calculation of amount of organic carbon in accumulation layer per ha;

    3) calculation of amount of total N in accumulation layer (usually - organic carbon divided by 10);

    4) calculation of N mineralized every year (1-2% of total N).

    It is necessary to remember, that amount of N mineralized every year cannot be recalculated into amount N mineralized every month - it depends especially on weather/moisture, determining soil microbial activity.

  • Frenkel Guisado Bourzac added an answer in ICP-MS:
    How reliable is the direct spectrophotometric determination of ions (not colorimetric) in water samples and / or biological extracts?

    I need to measure some ions concentrations, like phosphate, sulphate, bicarbonate, calcium, magnesium, ammonium, potassium, sodium ... but generally literature has reported colorimetric methods by direct reaction and / or by complexing. The main disadvantage of these methods is the cost of many specific reagents and / or access to modern devices for more accurate spectrophotometric determinations such as ICP-MS and atomic absorption techniques.
    On the other hand I would be interested in non invasive methods that do not destroy the biological samples for furthers determinations.
    Who can help with articles, methodologies and/or bibliographic references?

    Thanks in advance for any collaboration!!!

    Frenkel Guisado Bourzac

    Dear Ade,

    I downloaded all the files you attached to me. Useful information that I will consider when planifing coming projets for ecotoxicology studies in freshwater ecosystems near human settlements.

    I sent an application to Rockefeller foundation for funding in this topics. If accepted I´ll contact you. Have in mind if equipment can be shipped to Cuba. Answer me soon.

    Kind regards, Frenkel

  • Mohamed Ezzat Elshamy added an answer in Rain:
    From where can I get the data of rainfall of various rain gauge stations?

    As i want daily rainfall data, can someone tell me the procedure and also about the cost of one single rain gauge station data from IMD?

    Mohamed Ezzat Elshamy

    Depending on your specific purpose for obtaining the data and the time step, you may check GHCN. It is global monthly rain gauge data which is downloadable for free at http://www.ncdc.noaa.gov/ghcnm/ 

    There are also several global rainfall products that are grid-based on gauge data only like CRU or mixed with satellite/radar/reanalysis data. Look at this guide for all climate data and filter it for rainfall:


    Hope these resources help

  • John Sosa added an answer in TEM Image Analysis:
    How can I perform analysis of XTEM images?

    any software which is used to analysis the images .

    John Sosa

    I would defintely recommend you visit www.MIPAR.us.

    It is very powerful and intuitive 2D/3D image analysis software written by scientists/end-users and is about to be released as a free trial on December 14th. You can sign up on the site as well as submit images/datasets to test.

    There are many image analysis options available, but I think you may just find MIPAR to be something special if you give it a try!

  • Alireza Ahani asked a question in Hydrodynamics:
    Which grounds are more interesting in submarine manoeuvre and control from hydrodynamic point of view?

    Which grounds are more interesting in submarine manoeuvre and control from hydrodynamic point of view?

  • John Sosa added an answer in Edge Detection:
    Does anyone have suggestions regarding edge detection software for flow mediated dilation analysis?

    I am currently looking for edge detection software out there and I have only found 2 companies that offer the software (Quipo and Medical Imaging Applications). If anyone has used either please let me know about your experience and please share any possible suggestions.

    John Sosa

    I would defintely recommend you visit www.MIPAR.us.

    It is very powerful and intuitive 2D/3D image analysis software written by scientists/end-users and is about to be released as a free trial on December 14th. You can sign up on the site as well as submit images/datasets to test.

    There are many image analysis options available, but I think you may just find MIPAR to be something special if you give it a try!

  • Nnamdi Enyereibe Ekeocha asked a question in Rainfall:
    What is the best way to evaluate slope failure in a shale formation?

    I want to evaluate failure of slope in a shale formation but get faced with continuous washing of the slope face due to high incidences of rainfall.

  • Paul Engler asked a question in Xcalibur:
    Which opensource/freeware can I use to analyse my UHPLC-MS/MS data obtained under a .RAW format?

    Hello all,

    as I am quite often away from the lab facilities, I would like to know if there are any open-source/freeware that I could use to analyse my data (obtained from Xcalibur v.1.0.2, ThermoScientific, .RAW format) on my computer. I have had a look already, but it seems that most of the ones I found work with command lines and/or are for GC-MS.

    As I use R for statistical analysis, I have some knowledge in command lines, but I am a lot more at ease with a graphic interface.

    I would mainly use it for the qualitative and quantitative analysis of MS/MS spectra, but I would like to be able to also have a look at the UV/Vis absorbance spectra.

    What do you use for this kind of application? What do you recommand? Have you tested some of them and if so, which one would you recommand?

    It might be relevant to note that I use Wondows 7 or 8. I can also use Ubuntu if there is no other choice.

    Thank you very much in advance.

    Wishing you a pleasant day.

  • John Sosa added an answer in Particle:
    Is there anybody who has "image analysis software" for dirt particle analysis (TAPPI)?

    I need this software for my study.

    John Sosa

    I would defintely recommend you visit www.MIPAR.us.

    It is very powerful and intuitive 2D/3D image analysis software written by scientists/end-users and is about to be released as a free trial on December 14th. You can sign up on the site as well as submit images/datasets to test.

    There are many image analysis options available, but I think you may just find MIPAR to be something special if you give it a try!

  • Marcos Vinicius Santana added an answer in AutoDock Vina:
    Any advice on the virtual screening with Vina?

    Hello, guys

    I'm doing a VS with Autodock Vina using the following script:

    #! /home/marcos/Área de Trabalho/VS

    for f in *.pdbqt; do
    b=`basename $f .pdbqt`
    echo Processing ligand $b
    mkdir -p $b
    vina --config conf.txt --ligand $f --out ${b}/out.pdbqt --log ${b}/log.txt

    My question is, how can I save all out.pdbqt files in a single place and with different names.

    For example:

    My ligands are Ligand1, Ligand2 and Ligand3. I want 3 pdbqt files called Ligand1_out.pdbqt, Ligand2_out.pdbqt and Ligand3_out.pdbqt. What is the correct script language?

    Marcos Vinicius Santana

    Thank you, Yoshinobu and Vinod!

  • Krishnan Umachandran added an answer in Data Science:
    Are there any interesting recent research trends which combine data science and control theory?

    Dear all,

                  I would like to know that are there any interesting recent research areas which combine data science with control theory? If there are, which are they?

    Krishnan Umachandran

    C3 Energy data scientists bring knowledge from extensive research in computer science and engineering fields ranging from large-scale data mining to control theory

  • Sabah Vs asked a question in Battery:
    Despite it being the most popular battery chemistry why is there no proper research on fast charging of a lead acid battery?

    Lead acid batteries share the worlds major share of battery storage.Battery charging currents of lead acid are .2 C or .3C ,these charging limitation with the lead acid are tweakable and it can accept currents of 1C or more,i have been trying to find some research on this but i was disappointed.In early 90s there were several reported researches who were trying to develop fast chargers for lead acid batteries.Can someone guide me to some recent researches on this topic,if any.Thanks in advance

  • Daniel J Levendowski added an answer in Sleep Deprivation:
    Does anyone have the scale on sleep deprivation?

    i m intended to measure it as a mediator 

    Daniel J Levendowski


    Will you be able to obtain a baseline on the subjects before they are provided excessive work or is the assumption that if they are not getting a reasonable 6-8 hrs of sleep per night and they are active during the day then the poor sleep is a result of the work?  Kind of a chicken and egg question...The subjective scales described previously will measure sleepiness/fatigue but do not directly measure sleep deprivation.  Take a look at the work Dave Dinges (UPenn) and Greg Blenkey (US Army and now Wash State U) have done associating psychomotor vigilance task performance with sleep deprivation. We did a study a few years ago with military personnel across a 28 day exercise, used the scales described above, actigraphy and performance from a 3-choice vigilance task and it took until the 4th week of the exercise for the sleep deprivation related performance degradation to occur.  We found a 3-choice task (where there is decision making in addition to reaction time) is more sensitive than the standard PVT.

  • Nico Burgelman added an answer in Railway Engineering:
    In rail wheel interaction,how temperature plays an important role and what is its influence in calculation of stress?

    In rail wheel interaction,how temperature plays an important role and what is its influence in calculation of stress?

    Nico Burgelman

    The most important effect of temperature is on the pre-stress. Continuous welted rail is often designed to be stress-less at a temperature of 25-35 deg. So a lower temperature would mean the rail has a tensile stress while higher temperatures mean the rail has a compressive stress. This stress should added to the stresses caused by the wheel if one is to study stress related phenomena (RCF, plastic deformation, ...)

  • Marcelo L. Wilde added an answer in BOD:
    How can you explain very high COD values as compared with BOD in saline lakes?

    In some water bodies of Central México with solonchak soil type, We have been recorded high values of chemical oxygen demand in a rate of several times the values of biochemistry oxygen demand.

    Marcelo L. Wilde

    Dear Jacinto,

    What kind of methodology are using to analyze the chemical oxygen demand?

    If you are using the classical method with potassium dichromate, it is well know that Chlorine ions are a major interference in the COD analysis. As saline waters have a high content of Chlorine ions, it can causes a positive deviation in COD analysis.

    Just in case, I think that instead using COD, a total organic carbon (TOC) analyzer would be the better choice in this case.

    Best regards,

  • Farid Faridani added an answer in Soil Moisture:
    Can you name a soil moisture point between Saturation and Field Capacity? How can I define it for different soil textures?

    I have a number of hourly time series of soil moisture. In these time series, TDR never measured values near soil saturation, but my max values were alway at a certain point between Saturation and FC. So I thought maybe there is really a soil moisture point between Saturation and FC.

    Farid Faridani

    I used the data series from the SCAN database. So, I think the calibration and usage of TDR must have been correct. 

    what I mean is that for example you know that there is a point called FC and you can easily find this point for all soils in the refrences. Now, is there a similar point higher than FC?