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  • Luis Eduardo Carrion Rivera added an answer in CST Microwave Studio:
    How can one extract/export 2D data from CST MicroWave Studio (to, e.g., ASCII format)?

    I ran a time-domain simulation and recorded the electric field in a certain plane at some specific moment. This way I obtain a neat 2D contourplot inside the CST programme. The data used to produce this plot, I would like to export.

    There is in fact an Export option "Plot Data (ASCII)", but after having entered some step width in the x-direction (which is perpendicular to my plane...) the software yields an error or produces a small text file without any numerical values.

    Maybe it is possible to extract the data directly from some file in the associated Result directory? The exotic file extensions, however, make this a non-trivial task; maybe someone with more experience in this field could help me out?

    Thank you in advance for your interest and any help.

    Luis Eduardo Carrion Rivera

    CST exports data for every cell in the whole plane of the computational space. There is a column for Ex, Ey and Ez. Maybe you can share a picture of the model and the file to chck where is the problem.

  • Asa Wu asked a question in Hemocytometer:
    Is there any software to count cell number from image taken from hemocytometer or cell culture?


    Is there any software to count cell number from image taken from hemocytometer or cell culture?

    Could you kindly recommend me the software? Is it free?

    Thank you


  • Kim Rawlins asked a question in Cell Aggregation:
    What are some suggestions on completely detaching adherent cells from multi-well plates?

    I am having problems completely detaching adherent cells from 24-well plates. Cell aggregates are especially prevalent around the edges of the wells. I have tried trypsin and TrypLE to detach, and still see many cells attached following treatment.

  • Zameer Hussain Shah asked a question in PEAKS:
    In which case the TEM and XRD can not identify supported metal or metal oxides?

    I have prepared Manganese oxides insitu grown during the synthesis of silica nano spheres with fibrous morphology by one step hydrothermal process. MnOxides concentration shown by XPS is 0.13% while by ICP-AES is 1.1%. EDS also give the peak. XRD only gives the standard peak for Silica at 22 but there is no peak of Mn-Oxides. If compare the pure Silica TEM with Mn oxides incoporated Silica, there is only a little distortion in the samples but no Mn oxides can be observed. so i believe that Mnoxides may be well dispersed or embedded or  without any aggregation to be visible by TEM or detected by XRD. Please anyone can comment that TEM and XRD results are mutually consistent or not?

  • Beatriz Akemi Mizoguchi asked a question in Taqman:
    Looking for a TaqMan qPCR mastermix for multiplexing?

    I want to run a multiplex qPCR with TaqMan probes. The machine we have has ROX/FAM/HEX/Cy5 as filters. Does anyone knows a mastermix compatible will all these filters?

    Thank you in advance

  • Marina McDew-White added an answer in Schizonts:
    Does anyone have any Plasmodium synchronization tips?

    I am trying to get my plasmodium falciparum parasites synchronized to a 1hr time frame. I do a treatment of 5% sorbitol at 15hpi, then repeat at 5hpi. At 48hpi I run them through a MACs column to purify bursting schizonts, allow to grow for 1 hour and purify with sorbitol to get young rings. It seems as though my sorbitol treatments are too efficient because I still have schizonts and trophs in my culture when I should only have the young rings. Any have suggestions on how to make my window of synchronization tighter without putting stress on the parasites? Thank you in advance!

    Marina McDew-White

    Thank you everyone for your answers, all have been helpful! Is Plasmion available here in the states?

  • Bob D. Skiles added an answer in Science Education:
    What ways have you found to be effective to deal with students' misconceptions in science?

    My students learn biology and other sciences in English. Recently they had the Mid-semester test. Two of my 90 students had an F grade. When I checked their answers I found they had many misconceptions. Even simple questions like formation of a dipeptide; simple structure of a nucleotide were wrongly answered. The students admitted that they studied at the last minute.

    Any suggestions how to help such students with their misconceptions/confusions? I I believe it is related to their lack of motivation.  They take life easy; so different from the time when I was a student.  All my class mates worked hard to achieve, for the sake of our families.  Besides that, we found that science was interesting, and this fueled our curiosity.

  • Petru Moldovan added an answer in Wear Testing:
    Any advice on the tribology of self lubricating composites?

    I am working on tribolgical study of sintered iron based composites with certain reinforcements in different percentages and am facing a difficulty while going for high temperature wear testing. Since the base matrix is same and it is a comparitive study, kindly help me out in the problem of oxidation as how to tackle the problem of oxidation of composites at 500 degree celcius since I dont have any inert atmosphere

    Petru Moldovan

    You cannot solve the problem without inert gas.

  • Arbind Kumar added an answer in Cell Nucleus:
    How is a "large" nucleus-to-cytoplasm ratio defined?

    In histology or pathology texts, I frequently come across statements asserting that "a high nucleus-to-cytoplasm (N:C) ratio in 'x' cells is indicative of cell malignancy". What I do not typically find however is the threshold at which a N:C ratio for a given cell line may be considered "high". 

    I understand that these ratios vary between different cell lines, and so there is no one size fits all answer for this question; however, how is it that decided that for lymphocytes a 'high' N:C ratio is above 4, and for cervical cells it's greater than 0.3? Is there a handbook or gold standard reference for these sorts of metrics?

    Thanks for reading!

    Arbind Kumar

    Ofcource, without any doubt comparison  

  • Alexandro Rodríguez-Rojas added an answer in Microbiology Techniques:
    Can I reuse the coverslips after bathing them in sulfuric acid overnight to remove the APTS as substrate for organic tissue?

    I use coverslips treated with APTS as a substrate for tissue. Can I reuse the coverslips (treat them again with APTS) after I bathe them in sulfuric acid overnight?

    Alexandro Rodríguez-Rojas

    One possibility is to treat them with Piranha solution. This is a mixture of sulfuric acid and hydrogen peroxide. The typical mixture consists of 3 parts of concentrated sulfuric acid and 1 part of 30% hydrogen peroxide solution. This is much more effective than sulfuric acid alone. Be careful, because it is very dangerous. Prepare this using protection in a fuming hood. Piranha solution should be prepared by adding hydrogen peroxide to sulfuric acid very slowly, never the opposite. Use always a fresh made solution and do not reuse it. After the treatment, wash the glasses with abundant distilled water. I hope this helps.   

  • Emil Berengut added an answer in Injury:
    What are good management strategies of ucl injury?

    Just looking for different opinions of management strategies. 

    Emil Berengut

    Wilk KE, Reinold MM, Andrews JR. Rehabilitation of the thrower’s elbow. Clin Sports Med. 2004;23(4):765-801, xii.

  • Khoa D Tran added an answer in Flying:
    Does any one know which antibody is available to detect the gal4 protein in Drosophila?

    Recently when I'm trying to determine the expression level of GMR-gal4, and I found I was in trouble since the gal4 antibody didnot work. So I'm wondering if anyone have used the gal4 antibody in fly samples?

    Khoa D Tran

    There is a GAL4 antibody out there.  I've never got it to work in my hands.  Cross your line to a UAS-nlsGFP (nuclear localization) to make sure the GFP doesn't get inherited by daughter cells.  Don't do timing studies this way due to the reasons J. Pearson listed above. If timing is important, do an in-situ against the gal4 or GFP transcript.

  • Jai Ghosh added an answer in Enzymes:
    How can I measure the binding energy experimentally?

    I have a wild-type enzyme 'Ewt' and few mutant forms of this enzyme ('Emut1-Emutn'), and I want to compare energy of binding (Gb) of a substrate 'S' to these enzymes. I know that binding energy can be estimated in silico, but how can it be measured experimentally? I need to determine the association constant (Ka) and solve the equation (G = -RTlnKa) or there could be other options?
    Thanks for any suggestions in advance.

    Jai Ghosh

    Dear Sergii

    If I were you, I would prefer to use the computational biological tools (or you may call these as bioinformatics tools) to find the accurate binding energy. To do the esame experimentally, you need to determine the equilibrium and god bless you if if it a Rapid equilibrium condition. It is very difficult to get reproducible results on repetition.

  • Patricia Rodriguez de Gil added an answer in Discriminant Analysis:
    How can I asses if the distance between centroids is significant?

    Once I've established that at least one discriminant function is able to discriminates my groups, how can I assess if the reduced distance between centroids, that this function produces, is significant? should I use the standard criterion of +/- 1.96 SD (due to the fact that this function is expressed in standard units)?

    Patricia Rodriguez de Gil

    Hi Federico, thank you for pointing out that specifically, you would like some measure of the distance between the means of the groups in DF analysis. Like everything, it depends on what are the research condition of your study and what specifically are your research questions. But, I am thinking that maybe Mahalanobis distance could get the measure you are looking for. Best, Patricia

  • Syed Abrar added an answer in Smart Grid:
    Is there any architecture existing which employs cloud computing for smart grid?

    Hi every one!

    I intend to workout in the domain of smart grid and interested in architectural model based on cloud computing for smart grid, I have searched over internet but not find any such architecture.

    Can some one guide me in this regards, i.e what are the existing architectures for smart grid, is any architecture based on cloud??

    Thank you in advance 

    Syed Abrar

     Respected Mathias Uslar, Thank you for your kind guidance. Actually I am looking to design a smart resource selection in smart grid, which will be beneficial for electricity provider and consumer to select the optimize available source of energy. The smart resource selector will be integrated to via cloud. The optimum level of operation / consumption will be conveyed to power producer and user respectively.

    I had viewed your profile, and found that you had done a substantial work in Smart Grid. Can I be lucky enough to work under kind guidance?

    Thank you

  • Hussin Jose Hejase added an answer in Security:
    Is there any research on how to measure an organizations overall security awareness (not just information security awareness)?
    Like interviews, surveys, or something like that.
    Hussin Jose Hejase


    Check this paper


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Many believe that the coming war is a cyber-war that revolves around cyber weapons; to many others, the world is already at the core of this war. Names like Stuxnet, Duqu, Gauss and Flame have become familiar, malware projects known to experts in the field of cyber weapons. One asks: what type of awareness and preparation students need to deal with the cyber warfare challenges and threats? Countries have prepared for the aforementioned challenges and threats, while Lebanon is not. This research investigates current status of cyber warfare awareness and clarifies what changes may be incorporated into the Lebanese sectors, including the educational one. This study is exploratory and uses a survey distributed to 635 students, educators and managers. Findings reveal that in Lebanon, the educated community not only lacks awareness but also knowledge of what is happening in the arenas of cyber warfare, cyber weapons and cyber security.
  • Zameer Hussain Shah added an answer in XPS:
    What is the minimum concentration of the supported metals or metal oxides to be detected by XPS?

    i have prepared Manganese oxides insitu grown during the synthesis of silica nano spheres. MnOxides concentration shown by XPS is 0.13% while by ICP-AES is 1.1%. so such XPS data is reliable and acceptable? 

    Zameer Hussain Shah

    Thanks Dr. Kaciulis. i learnt a lot from your kind reply

  • Arles Rodriguez added an answer in Artificial Intelligence:
    Do you know a paper in artificial Intelligence field which solves how to put together lego blocks to make a specific shape?

    Hi All,

    I am looking for an algorithm which can help me to implement an artificial intelligence so as input, I give it specific shape made by lego blocks and then, it puts the lego blocks together to make that shape?

    Arles Rodriguez

    This book can be interesting: http://www.springer.com/us/book/9783642339011

  • Mohamed El Naschie added an answer in Zeta Function:
    What are the current application of Riemann Zeta Function in analysis of elementary particles?

    I want to know the applications of Riemann zeta function in analysis of elementary particles and other high energy physics phenomenon.

    Mohamed El Naschie


  • Kaarel Kõivupuu added an answer in Western Blot:
    Does anyone have experience with a western blot gel polymerization problem?

    After running several Western blots I ran into a problem that I didn't seem to find an answer to from here. The gels polymerize evenly except for the bottom 2-3 millimeters - if I remove the plate from the stand  a little bit of liquid drops off, leaving a rather ugly zigzag looking bottom edge. It's not a big problem, but rather unfortunate as I need a clear view on smaller peptides on my blots as well and a clear edge on the gel would definetly help. 

    To avoid some question - I have new APS, roughly a month old acrylamide stock that I keep in the dark (and cold) and the separating buffer is roughly of the same age and should be in order. TEMED might be a question mark, though as much as I understand it works only as a catalyst and should play a role here (in case of a problem with TEMED I should get a bad gel in general). I wash my glassware every time as well. The gel that I'm trying to run is 12%. 

    Kaarel Kõivupuu

    I let them polymerize for 30 minutes, I also keep the leftovers in a Falcon and I get the same there - generally a good polymerization, but with some leftover fluids (a couple of drops basically). My first idea was APS, but I did a fresh batch (10%). For my separating gel I add 90 ul for 15 ml of mixture. Perhaps I should increase the amount (or decrease it, might be also a possibility - perhaps the polymerization is too quick, if that makes sence in any ways)? 

  • Maximilia Christina Hottenrott added an answer in Protein Extraction:
    Any advice on cytoplasmic and nuclear protein extraction from frozen rat lung tissue?

    I have frozen rat lung tissue and I would like to look at the transactivation of NFkB in these samples. One of my colleagues said that the samples are stored at - 80C might be a problem and we are looking for a good protocol, any suggestions?

    Maximilia Christina Hottenrott

    Our samples were also snap frozen, same can be a problem in your samples.

  • Arles Rodriguez added an answer in Regression:
    Genetic Algorithms outperform Artificial Neural Networks ???

    Can Genetic Algorithms (or GP) outperform Artificial Neural Networks?

    ANNs try build a "complex" mathematical function that best fits a given input to an output. This principle was used largely to solve a wide range of problems: classification, prediction, clustering, etc.

    GP (and GAs) proved their abilities in building complex functions (symbolic regression, non-linear regression, etc.) that maps (input, output).


    Is it possible to make GA (or GP) outperform ANNs (or at least behave exactly as) GAs (or GP algorithms)?


    If GAs > ANNs - forget about No Free Launch Theorem for the moment:)  so why GAs are not too "reputed" in such domains?


    What is done by ANNs and cannot be done with GAs or GP based algorithms?

    Arles Rodriguez

    You can even combine both techniques evolving the neural network. I think difficulty depends on the constraints each model have: in neural networks to determine the number of layers and networks and in genetic algorithm selection of population size, genetic operators and fitness function.

  • Ian Diner added an answer in Streptavidin:
    Does anyone have experience with elute biotinylated proteins without eluting avidin as well?
    We are using Life Technologies MyOne Streptavidin T1 beads to pull biotinylated proteins out of a cellular lysate for downstream analysis by LC-MS. Following the manufacturer's protocol, I elute the proteins by boiling the beads in SDS (0.1% or 2.5%). There is a significant contamination from streptavidin in the eluate. Estimating protein abundance based on spectral counts, streptavidin is anywhere from 2x to 10x more abundant than the most abundant target protein.

    Has anyone found a way to elute biotinylated proteins with minimal elution of streptavidin? Has anyone tried pre-treating the beads (e.g., boiling in SDS) to reduce elution? I don't know if the eluting streptavidin was non-covalently adhered to the bead, or if the elution protocol is actually breaking the bead-streptavidin bond.

    (With these same beads, we did notice significant amounts of BSA eluting as well, despite the fact that the beads had been washed several times before and after protein capture. These beads come blocked with BSA to prevent non-specific binding. We are going to try switching to the C1 beads, which are not blocked.)
    Ian Diner

    Yes boiling in SDS does elute streptavidin monomer, but it doesn't interfere with shotgun proteomic analyses (i.e. by swamping out signal from peptides of interest). You can also build an exclusion list with the common streptavidin peptides if necessary. 

  • Xiangdong Hu added an answer in Tunneling:
    What is the difference between Circular and Double-O-Tube Shield Tunnel ?

    adapting to analyze the inner force in lining

    Xiangdong Hu

    In addition to Dr Zheng's comment, sometimes "side drainage sumps" are to be built outside the tunnel. The side sumps are often built by artificial ground freezing. 

  • Mrugesh Joshi asked a question in Vorticity:
    When water is drained through sink, free vortex is formed due to Coriolis effect. How can I model this phenomenon mathematically?

    I am trying to find pressure and velocity distribution of irrotational vortices, and was able to find the equations at far from the vortex core, but I want to know what happens near the core where axial component of velocity exists. How to find circulation around the core? Is it related to rotation of earth? If so, then how? What are governing equations? Any guidance regarding it will be helpful.

  • Muhammad Shahid added an answer in Runoff:
    Which method do you recommend for estimating monthly and annual runoff data when you have monthly and annual inflows in million gallons, ?

    Which method do you recommend for estimating monthly and annual runoff data when you have monthly and annual inflows in million gallons, monthly and annual precipitation and temperature data as available data

    Muhammad Shahid

    Victor Popovych What about this conversion?

    I have Inflow in Million gallon I will convert it into Acre-feet 

    Runoff in feet = Inflow in Acre-feet / Catchment area in Acres

    Runoff  in millimeter = Runoff in feet*304.8

    I have done conversion by using this formula excel sheet is attached kindly guide me is this valid conversion.  

  • Alessandro Vigliani added an answer in Vehicle Dynamics:
    Does the braking distance of a car depend on weight of the car?

    d = v2/2ug, 

    d = minimum stopping distance,

    v = velocity when brakes were applied

    u = coeff. of friction between wheels and road

    g = gravitational constant,

    The above equation shows that braking distance is independent of mass of vehicle. I know that depending on the value of slip, the value of 'u' will change, but lets assume that 'u' is constant. So does it mean that two different vehicles, one a normal car and other a sports car would have a same braking distance for a given same 'v'. I am confused because this does not seem to be the case. What am I missing?

    Alessandro Vigliani

    You are right: theoretically, braking distance does not depend on mass. But in practice, yes. The explanation is that tire effective friction coefficient cannot be assumed constant: it slightly decreases with increasing normal force. So braking distances are longer when more mass is added. As a limit example, consider that on trucks, the tire coefficient usually is smaller than 0.65 even on dry roads>