Q&A

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  • Eirini Kakkava asked a question in Nanoparticles:
    Nanoparticles' characterazation

    How is it possible to discriminate if a colloidal solution contains metal or metal oxide nanoparticles and maybe it what ratio? Which characterization technique is the most suitable?

  • Has anybody used Glue on VHF transmitters on mammals?

    Hello,

    I may have access to around 30, 9 grams VHF transmitters that, for a series of reasons, are not going to be used.

    I was planning on radio tracking Agile wallabies in the near future (depending on funding), and for that I was going to use collars. However, since these transmitters are available I was wondering if anybody has experience on using glue on tags on medium size mammals.

    Cheers,

    Miguel

    Andrew Damon Lowther · Norwegian Polar Institute

    for marine mammal scientists, the only way to attach telemetry devices to pinnipeds is using glue (with a very small number of exceptions), so to answer your question, 'yes, plenty of experience', and I couldnt see a reason why you cant glue small vhf tags on wallabies.  But I guess what you should consider is the time glue takes to set ('go off'), and the temperature that the glue rises to as it is setting.  Typical glues we use on seals go off in 15-20 minutes and rise to temperatures of 34-36 degrees celcius.  You should also consider where you glue, and how the position on the body (and the animals locomotor behaviour) will affect the reception of vhf signals.

  • What is the role of arachidonic acid cascade in cancer?

    How are the Arachidonate metabolites involved in carcinogenesis?

    Michael J Gonzalez · University of Puerto Rico, Medical Sciences Campus

    Favors cell proliferation via prostaglandin mechanism and cell membrane formation.

  • Jing Yang Tee asked a question in Cell Migration:
    Does anyone here use Operetta (Perkin Elmer) to measure live cell migration?

    We have an Operetta which I've tested but it seems to have a x-y drift problem which is not due to any mechanical faults according to the manufacturer.  Would like to hear from other users regarding this.

  • Can inferential statistics be applied to purposive samples?

    Can inferential statistics be applied to purposive samples?

    Josh Makore · Department of Agricultural Research - Botswana

    No. Eddie gave a very good answer.

  • Peng Bao asked a question in Glycolysis:
    Ask for article

    Dear Xia

    I am now working on selenite effect on cancer, and i am very interesting in your paper:Mechanism of the anticancer action of selenium--influence on glycolysis and its key enzyme. 

    Would you please send me a PDF version?

    Many thanks!

    Sincerely Bao

  • Ahmad Shafiei asked a question in Stress:
    What is module in promoter of gene ?

    we want found  genes with same expression pattern in response to stress. 

  • Rabee Alhossiny asked a question in Restriction Enzyme:
    To know the class 1 integrons cassette are identical or not we digest them with restriction enzymes as hinf1, what is the concept to use hinf1?

    How we decide a restriction enzyme to cut unknown sequence.

  • Jennifer I Drake added an answer in NCBI:
    Can anybody tell me how to retrive microarray data from Gene Expression Omnibus (GEO) repository at the NCBI ?

    microarray data for analysis

    Jennifer I Drake · Virginia Commonwealth University

    Which type of file you download depends on what you use to analyze the files.  I typically use Bioconductor packages in R (http://www.bioconductor.org/) to do microarray analysis.  However, I typically work with different file types, so I can't recommend a specific package.  I'm sure there is one there for those files.

  • Jingbo Li added an answer in Xylanases:
    Does anyone know how to dissolve the Xylanase from Thermomyces lanuginosus (powder)?

    Link: http://www.sigmaaldrich.com/catalog/product/sigma/x2753?lang=en&region=CA

    Jingbo Li · Jinan University (Guangzhou, China)

    You can dissolve it in buffer or water as you wish. Christoph Ottenheim has explained it very detailedly. You can also see our paper for your reference. 

  • What do you think about an equation to precisely predict happiness?

    BBC report says scientists have developed a mathematical equation that can predict momentary delight. They found that participants were happiest when they performed better than expected during a risk-reward task.
    "We can look at past decisions and outcomes and predict exactly how happy you will say you are at any point in time," said lead author Dr Robb Rutledge from University College London.
    What is your opinion about this research? Now that we have an equation which can we use it in survey research to replace a Likert scale for such questions? Any further comments will help. Thanks.

    Robb B. Rutledge, Nikolina Skandali, Peter Dayan, and Raymond J. Dolan - A computational and neural model of momentary subjective well-being, August 4, 2014, doi:10.1073/pnas.1407535111

  • Julia Hentschel added an answer in Interleukin-6:
    Any alternative to expensive ELISA kits for IL-6 or other inflammatory markers?

    I need to quantify Interleukin 6 or IL-6 and couple other inflammation markers. The method I want to try is ELISA but ELISA kit is expensive. Any other alternative? 

  • What will patients be prescribed when Hydrocodone products become Schedule II pain medications?
    Due to continued pressures related to prescription drug abuse, the DEA and local state organizations (Boards of Pharmacy, Boards of Medicine) are considering the reclassification of Hydrocodone (and combination products such as Vicodin, Norco, etc) as a Schedule 2 medication.
    R. Michelle Baker · Cancer Treatment Centers of America

    I agree Alan - For years medication safety committees worked hard to decrease codeine prescribing...and the literature details the issues of questionable effectiveness, variable metabolism related to genetics, as well as having a negative side-effect profile.  Why does the US consume so many pain medications compared to the rest of the world.........

  • M. Farooq Wahab added an answer in Amination:
    What is the stablity of caroxyl and amine groups on carboxylated and aminated nanoparticles in a medium like PBS?

    what is the stablity of caroxyl and amine groups on carboxylated and aminated nanoparticles in a medium like PBS?

    M. Farooq Wahab · University of Texas at Arlington

    If it is silica, both carboxyl and amine groups will be pretty unstable in aqueous medium; more so in phosphate buffer. If you have used silanes to bond such groups onto silica, then the bonded layer will hydrolyse very soon. If you manage to cross link the siloxane bonds, then material may be very stable in aqueous medium. What is your bonding chemistry? There are many chlorosilane based crosslinkers.

  • Andrea Spitaleri added an answer in Gromacs:
    Can anyone assist me with adding probability of state on the projection of eigen vector PC1 vs PC2 plot in gromacs?

    I have performed the principal component analysis in gromacs and I have obtained the projection of eigen vectors PC1 vs PC2 plot as in figure 4B
    I would like to add information about the probability of occurrence of tat state as shown in figure 4C

    Thank you in advance

    Andrea Spitaleri · Italian Institute of Technology (IIT)

    Hi,

    besides  g_sham, you can do it either in gnuplot easily or using matplotlib library.

    hope it helps

  • Debasis Nayak asked a question in Thin Film Deposition:
    Can anyone suggest easy way to produce high conductive LISICON (also film/ thin film deposition)

    LISICON represents lithium super ion conductor

  • Han Geurdes added an answer in Quantum Entanglement:
    Could quantum entanglement be explained via quantum tunnelling of information?

    More precisely through quantum tunnelling of information via the time dimension.

    Han Geurdes · CGI plc.

    What is quantum entanglement ... ?

  • Vikineswary Sabaratnam added an answer in Biocides:
    Can you recommend 4-5 common Fungi and Bacteria to work with?

    I am considering starting a project regarding some non-specific biocides.  What would be the best 4 or 5 fungi and the best 4 or bacteria to test it on?  Ideally the organisms should be common in the environment, interact with humans, and not cause significant illness.

    Vikineswary Sabaratnam · University of Malaya

    I will go with spp suggested by Peter. 

  • Mahfuz Judeh added an answer in SPSS:
    Why do we do transformation before data analysis?
    What are the situations in which we need to do transformation and how can we do it?
    Mahfuz Judeh · Applied Science Private University

    Many functions can come under the title, “Transformation”, such as: 

    Compute Variables: You may need to compute a new variable based on existing information (from other questions or variables) in your data.

    Recode: You can create new variables with compute and you can modify the values of an existing variable with recode.

  • What is the exact way of calculation of limit of detection (LOD) and limit of quantification (LOQ) on method validation studies?

    Most of the method validation studies have used the signal to noise ratio  (S/N) of 3 and 10 for LOD and LOQ respectively. LOD=3x(S/N) ; LOQ=10x(S/N)

    but in this case the reports on some of the papers are a bit confusing, eg: (mycotoxin determination method validation, AFB1 and OTA are the target compounds to be detected by LCMS/HPLC...)

                     LOD      LOQ

    AFB1        0.1        0.4

    OTA         1.2        2.9

    from the LOD of AFB1 we calculate the S/N=0.0333 (S/N=LOD/3) . then if we calculate the LOQ (LOQ=10x(S/N)) should be 0.333 but it reported as 0.4. This is the same for the LOQ of OTA. (should be 4 but reported 2.9).

    is there any one can give me detailed explanation?

    Thank you so much for the consideration.

    Kiran Khandelwal · CSIR-Central Drug Research Institute,Lucknow, India

    ICH guidelines Q2RI explain the term LOD and LOQ in a very simple language, it also describes different methods to determine  them.

  • Does it make sense to assess uncertainty in climate change impact projections?
    It is now widely admitted that climate change impacts on water resources are occurring and are expected to amplify in the future. However, these impacts are highly uncertain and usually scientist and decision makers prefer to have a quantitative assessment of these associated uncertainties. How can we assess future uncertainty related to climate change in the absence of observations? Then, how can decision makers consider these uncertainties in their future plan management of water resources for instance?
    Husain Najafi · University of Tehran

    In a recent commentary in the nature climate change by Katz et al., (2013), the authors highly suggested that there is a need to include at least one author on all chapters of IPCC with expertise in uncertainty analysis to enhance the quality of the treatment of uncertainty. The statement reveals that despite the importance of incorporating uncertainty, its present treatment is viewed as quite inadequate. For the case of climate sensitive systems, to the best of my knowledge, uncertainty quantification is treated poorly in the current studies especially when climate change impacts on water resources and hydro systems are concerned. Apart from only a few exceptions, uncertainty analysis is overdue in relation to precision, model and measurements errors as a whole; Current studies have referred mainly to one type of the mentioned errors in isolated and fewer have attempted to consider all in one study. This may root in the fact that water resources engineers alone cannot solve challenging problems in quantification of uncertainties associated with climate change. Rather, increased collaboration between statisticians, climate scientists and water resources decision makers is compulsory.

  • What is the intensity value of brain tumour in MRI imaging?

    How do we differentiate brain tumor on the basis of its intensity value.

    Apoorva Pramod Safai · VIT University

    Thankyou Sir, all of your answers  and reference material were really helpful..

  • Peter Leupold added an answer in Turing Machine:
    Why can the Minsky Counter Machine emulate the Turinf Machine?

    Dear colleagues:

    It is shown that Minsky Counter Machine can simulate a Turing machine , for two counters can simulate a stack (a half tape in Turing machine). If 1 pushed in the stack, then double the counter plus 1; if 0 is pushed then double the counter. When multipliers and reminders in many steps are mixed in one counter, how to discriminate which step of a pushing? Where I can find the introduction to Minsky Counter Machine in more detail than Wikipedia ?   

    Peter Leupold · University of Leipzig

    Well, I am not an expert on this. But the key idea in these proofs is the following: a tape with an alphabet of n symbols can be interpreted as a number in base n. If i divide the tape at the position of the TM head, I get two numbers: one from the head to the first non-empty symbol, the other from the head to the first non-empty symbol. A move of the head can be characterized by a change in these numbers. Doing these changes on two counters simulates the TM.

  • R - Automatic labelling of points in a scatterplot avoiding overplotting of labels

    I attached an example of what I mean. This plot was generated manually. The algorithm should determine which points can be labelled (where is enough space to add a label; this will be typically for the "outer" points), possibly up to a given maximum number of labels. The labels should then be placed so that neither data points nor other labels will be obscured.

    The labelling should be done automatically (i have to generate really many of such plots, with many 100s of points of which the points at the outer range should be labelled)

    I know the "work-arounds" to plot the labels without the points and use a smaller font size, so that overplotting is less likely. But this is not applicable for me. The points must be visible and they are of a particular size. Also the problem remains how to determine the points that can be labelled (so that the labels ramain readable and do not overlap each other).

    I hope that someone already solved this problem (what I consider not too exotic, though...). Thanks for hints and helps!

    Jochen Wilhelm · Justus-Liebig-Universität Gießen

    That seems to be helpful at my first impression. Thank you!

  • Nuria Bermejo added an answer in Thrombophilia:
    What is the best time to initiate Thrombophilia and antiphospholipid antibody screening in a women who had recurrent miscarriages?
    Couples are very worried
    Nuria Bermejo · Hospital San Pedro de Alcántara, Cáceres, Spain

    At least it should be expected until day 21 partum, time in the physiological alterations in haemostasis return to normal before pregnancy, except for the study of FV Leiden and FII20210G/A mutations, that can be studied at any time.

  • Vikineswary Sabaratnam added an answer in Lignin:
    What is the most efficient method to separate lignin degrading enzymes such as Laccase, Mangnese peroxidase, Lignin peroxidase?

    The project title is “Studies on decolorization and detoxification of Molasses spent wash by group of lignin degrading enzymes isolated from fungus”. For this, I need to separate the above mentioned enzyme.

    Vikineswary Sabaratnam · University of Malaya

    If your aim is to decolorise and detoxify the waste - why the need to separate?  - the enzyme cocktail may work better. Further all separation techniques are expensive - ion-exchange, centrifugation based on molecular weight and aqueous two phase systems  - For bioremediation cocktails of enzymes can be applied. What is your fungus and what is the dominant enzyme that it is producing?  You may , however, need to concentrate the cocktail before the treatment.

  • Nicola Bombieri added an answer in OpenCL:
    Which one do you prefer: CUDA or OpenCL?

    I have noticed that CUDA is still prefered for parallel programming despite only be possible to run the code in a NVidia's graphis card. On the other hand, many programmers prefer to use OpenCL because it may be considered as a heterogeneous system and be used with GPUs or CPUs multicore. Then, I would like to know which one is your favorite and why?

    Nicola Bombieri · University of Verona

    CUDA for performance, OpenCL for portability...

  • What would the concentration of an OH-radical in a gamma-irradiated water sample be?

    I want to measure the concnetartion of OH-radical in a gamma-irradiated aqueous sample.
    Any help will be appreciated.

    The detail for calculation of hydroxyl radical concentration can be found in Spink and Wood book as well as in "Radiation induced decompo-sition of methyl tert-butyl ether in water in the presence of chloroform" by Basfar et al., Water Research 39 (2005) 2085–2095. It is done from the G-value equation and using the G-value for hydroxyl radical from the water radiolysis equation

  • Prerna Mishra asked a question in Public Assistance:
    Free journals publication for assistive technology

    i want all free journal publications for assistive technology. kindly tell.

  • Chirag Bhalara added an answer in Web Services:
    Is there a specific tool for identifying Cloud Traffic ?

    Can someone suggest a tool that can identify Cloud Traffic or can differentiate Cloud services from other web services...

    Chirag Bhalara · Gujarat Technological University

    cloud stack neat