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  • Haoyang Jiang added an answer in Affinity Purification:
    How might I improve calmodulin beads binding in tandem affinity purification?

    In my purification with Tandem Affinity Purification (TAP), I find lots of target protein stayed in the solution instead of binding with Calmodulin beads, though there is some binding with the beads. Is there any way to improve this step?

    Thank youi!

    Haoyang Jiang · Pennsylvania State University

    Really appreciate you guy's answers. I didn't set a control for the beads and I would keep using 2mM CaCl2 this time but change the NaCl concentration from 150mM to 500mM, as my mentor recommended. Do you think this will improve the binding or it's really hard to say? BTW, how should I check whether there is a conformational change or not?

  • Alain Manuel Chaple Gil added an answer in Implants:
    Which material is good for coating ?


    Alain Manuel Chaple Gil · Universidad de Ciencias Médicas de La Habana

    Titanium it's traditional but is a great material... regards.

  • Ijaz Fazil Syed Ahmed Kabir added an answer in FLUENT:
    Why do I detect stationary wall motion relative to adjacent cell zone?

    Dear colleagues,

    for simulating a rotating impeller I have used MRF approach,

    Although I have changed all the walls to moving wall relative to adjacent cells with with zero velocity and same direction, fluent error remains,and continuity remains high.

    I think it would be because of a mesh problem?
    Do you have any suggestion?

    Ijaz Fazil Syed Ahmed Kabir · Nanyang Technological University

    Check your interface also

  • Hajar Rajayi asked a question in Cancer Treatment:
    Enhancing of free radicals is a good idea in cancer treatment or not?

    There are new methods which focus on increasing ROS to induce apoptosis in cancer, but there are some others that are just working on application of antioxidants. I wonder if the decrease or increase of ROS in cancer is the matter? I want to know your idea. does it depend on the stage of the tumor or not? enhancing of free radicals is a good idea in cancer treatment or not?

  • Ijaz Fazil Syed Ahmed Kabir asked a question in Tdr:
    How to eradiacte the error whilerunning udf for Atmospheric boundary Condition in FLUENT at HPC?

    I have written UDF code for calculating velocity inlet, TKE and TDR at inlet.
    When I run in HPC in parallel, I get error some error.
    I have included this comment "#if !RP_HOST" in my udf
    and my journal file is
    /define/user-defined/interpreted-functions "/home/ijaz0001/july30/kepsilon.c" "cpp" 10000 no
    /file/read-case "/home/ijaz0001/july30/july30.cas"
    /file/auto-save/data-frequency 100
    /solve/iterate 10000
    /file/write-case-data "omega1_1_10000.cas"
    exit yes

  • Ardic Arikal added an answer in Liposomes:
    Can someone help me with monitoring liposome fusion?

    I will be incubating mammalian cells with DOTAP containing liposomes and I would like to to verify that the liposomes are fusing with the cell.  I would appreciate any suggestions on this. 

    Ardic Arikal · University of California, Davis

    Thank you very much !  

  • Ravindranadh Koutavarapu added an answer in Nanomaterials Characterization:
    How do I find the crystal structure of nanomaterials?

    currently i am working on nano materials please help to find out the crystal structure nano materials

    Ravindranadh Koutavarapu · Acharya Nagarjuna University

    First u observe the formation of Nanoparticles and u study the XRD pattern using Xpert pro diffractometer. By using highest peak intensity using FWHM calculate average crystallite size of the prepared sample. Using JCPDS card number u may know the crystal structure of the sample.

  • Alessandro Bonadonna asked a question in Mountaineering:
    He european optional quality term "mountain product" could be considered a useful tool for small and medium farms sited in mountain?

    The european optional quality term "mountain product" could be considered a useful tool for small and medium farms sited in mountain? At present, in Italy this optional term is used essentially from food industry in dairy sector in order to commercialize yogurt and cheese.

  • Michael Issigonis added an answer in Archaeology:
    What is the future of taking care of our Cultural Heritage?
    Cultural Heritage has grown over the past decades to become one of the most pending questions to mankind. Individuals continue more than ever before to look into the very roots of their existence, which is a good thing to do. However, this root-treatment cannot be established by oral traditions only. One needs bio- and material cultural objects that reflect how our forefathers were living and left behind. Only since the mid 19th century, many of these artifacts are assembled in hundreds of museums where they are treated with good care. However, with the accumulation of artifacts and the restoration and necessary conservation of cultural objects, it will become a burden to pay for this type of work and as the assemblage will only grow, there will come a point in time that there will not be enough budget to pay for all that work. So, how do you see the future of Cultural Heritage?
    Michael Issigonis · Brandon University

     As academics we can only promote education and be passionate about it. The destruction of CH by extremists today is usually done with the tape & camera running for quick transmission around the world. Basically, the person shows off how little one cares about education, CH and also one's own family job if one works in tourism for example. If there was no media coverage, maybe one wouldn’t bother doing the destruction.

    Since the first whole scale CH destructions of the 6th century in the Middle East area this is a tremendous improvement (hard to say it). Now it is isolated events and always on camera. It is acts of violence and governments are slow to react ( or they support violence?) and coordinate among themselves. 

    Cross-breeding over the years has helped- promoted by Alexander, 4th cent. BC.

  • Soultana Kapiki asked a question in Serbia:
    Dear colleagues, is anyone having recent data (2012-2014) for the domestic tourism expenditure in Serbia?

    More specifically, I'm interested in the domestic tourism expenditure for Sports & Recreational Services (I already have the relevant data for 2011). Thank you in advance for your contributions!

  • Alberto González-Gallina added an answer in Conservation:
    Could someone point me to literature that examines what we need to know about a species to effectively conserve it?

    I'm talking about the whole range from basic understanding of conservation status and occurrence to mechanisms by which drivers of decline operate.

    Alberto González-Gallina · Institute of Ecology INECOL

    I agree, the IUCN has a good amount of articles related to each species there.

    I would suggest, first of all, learn as much as you can from your species biology. Once you know it better you can start looking at which things threaten it the most, trying to understand what really matters for this species, try being in your "species shoes". Try to figure out at what scale will conservation actions be relevant  and which actions are more prone to be undertaken effectively, etc.

    For instance, you may find that your species has a distribution of X, but along all the distribution, it only inhabits rocky formations of certain characteristics thus, you wouldn`t try to preserve everything, maybe only those formations in that species distribution...its a lot more complex, you have to keep in mind a lot of things, biological, social, economical, etc.

    Wish we could have a coffee and discuss the matter, its more complex than it seems.

  • Frederick Chali added an answer in Mobile Application Development:
    What are the challenges for integration of mobile applications with multiple databases running on different computer servers?

    I am researching how to improve/ support the mobile application development by creating a tools at the middle to the computer servers. Please help me to reveal the challenges.

    Frederick Chali · The Nelson Mandela African Institute of Science and Technology

    Dear Maya,

    Thank you for the consideration and an interesting advice. Surely I will follow the advice.

  • Fouad Aoun added an answer in Laparoscopic Surgery:
    Regarding Palmer's point entry would you recommend direct or Veress?

    Direct trocar insertion through Palmer's point with 10 mm trocar OR Veress needle insufflation prior to trocar entry through Palmer's point? Which one is preferable or practiced?

  • Veera Manikandan R added an answer in Alleles:
    CAn I use Bonferroni correction for multiple comparisons in genotypes and alleles?

    If I have 4 unrelated SNPs in the same study, for association with certain disease. I use Chi square for getting p value for each genotype and each allele, so I have 4 SNPs multiplied by 3 genotypes=12 p value. how can I use Bonferroni correction. and will I multiply p value by 4 (number of SNPs) or 3 (genotypes for each SNP) or (12 SNPs multiplied by genotypes)? or I will get only one p value for each SNP and multiply it by number of SNPs?

    Veera Manikandan R · Christian Medical College Vellore

    @Iman there is no comparison between SNPs. You are just trying to find out if any of the SNPs is associated with disease. More the SNPs I have to do the analysis more I get false positives. That is why you have a threshold in range of 10^-8 to 10^-12 in genome wide association studies, where you screen millions of SNPs for association. All the best.

  • Qasem Mousavi added an answer in Pesticide Analysis:
    How is it possible to increase the time for using an antibiotic in an environment before its decomposition?

    I want to apply an antibiotic in termite colony through their food. I'm afraid that the antibiotic is not stable enough in the wild environment and it will decompose soon. Is there a way to extend the antibiotic effect? Is there any materials which make the antibiotics more stable and hard to decompose? Of course without changing the original structure of the antibiotic. 

    Qasem Mousavi · University of Tehran

    Thanks, could you tell me which article can help me more.

  • Ingolfur Magnusson added an answer in Chitosan:
    What is the difference between using water and acetic acid when making chitosan particles?

    with which group of the chitosan reacts the acetic acid?

    Ingolfur Magnusson · University of Iceland

    Hi, do you know if chitosan will fold at basic conditions? Is folding of chitosan sometimes a problem in its synthesis?

  • Ishag Adam added an answer in Randomized Control Trials:
    What phase should a pilot randomized controlled trial be considered if it is designed for using a previously known intervention for a new indication?

    We are designing a trial to know about comparative efficacy of various interventions that were previously used for some other indications. What phase of clinical trial is it?

    Ishag Adam · University of Khartoum

    I think  it is phase 11 with  minimum numbers

  • Naresh Mehta added an answer in UCSF Chimera:
    How do I measure the distance between the corresponding amino acids of 2 protein chains which are superimposed using UCSF Chimera?

    I have superimposed homologous proteins on chimera. Few of the residues are identical, few other align but are not identical and the rest do not. I want to find the distance between the aligned but non-identical residues. Is there a function on UCSF Chimera that I can use?

    I know we can find the distance between 2 atoms on different chain but I want with respect the residues.

    Naresh Mehta · Central Institute of Fisheries Education

    Raman spectroscopy may help you.

  • Nagmani Nagmani added an answer in Gas Sensors:
    How can greater sensitivity and response time gas sensors made from powders of larger size to smaller size justified?

    hi.How can greater sensitivity & respone time gas sensors made from powders of larger size to smaller size justified?

    Nagmani Nagmani · Central University of Jharkhand

    you can try for partial oxidation of material (NPs or tin films) as SnOx, CuOx etc

  • Naresh Mehta added an answer in Protein Electrophoresis:
    Can the upper and lower tank buffers of tricine SDS PAGE be reused?

    In order to save the chemical and prevent the waste generation, can these two buffers be reused.

    Naresh Mehta · Central Institute of Fisheries Education

    I have used many times in 5-6 months. There were no problems till now. Tough if you keep for longer period, fugal growth occurs but that can be filtered.  But keep in refrigerator. 

  • Ziyad Ben Taleb added an answer in SPSS:
    Is it possible to carry out a metaanlysis with the SPSS?
    I wonder if with some extensions can I make an analysis of size effect?
    Ziyad Ben Taleb · Florida International University

    Hey Andy! thanks for posting the book chapter 17 on doing Meta in R. Would you please tell me the title of the whole book?

  • Dorian Aur added an answer in Turing Machine:
    Can we fully simulate the whole brain on a digital computer?

    Miguel Nicolelis and Ronald Cicurel claim that the brain is relativistic and cannot be simulated by a Turing Machine which is contrary to well marketed ideas of simulating /mapping the whole brain  https://www.youtube.com/watch?v=7HYQsJUkyHQ  If it cannot be simulated on digital computers what is the solution to understand the brain language?

    Dorian Aur · Stanford University

    Dear Colin , Theophanes

    Excellent observation regarding computing  efficiency .

    And now the fundamental problem: the molecular "switch" described in biology  is not  a digital switch.

  • Hero M. Ismael added an answer in Wastewater Treatment Plant:
    Does anyone know what species of fungi this is?

    I found this fungi on anaerobic compartment in wastewater treatment plant. this fungi is almost always occur when the wastewater in nitrogen deficit condition. wastewater source is from biscuit industry.

    does anyone know what species is this?or family at least? and why this fungi could live on wastewater treatment plant? and, are this fungi have negative impact for wastewater treatment plant efficiency?

    thanks before.


    Hero M. Ismael · Salahaddin University - Erbil

    it seems to be lichens the green color may be is algal part

  • Júlia Maria Antunes Valente added an answer in Essential Oils:
    Is anybody studying essential oils and their cytotoxicity?

    Especially IC50 

    Júlia Maria Antunes Valente · University of Coimbra

    Hello, our work is with essential oils. We evaluate their biological activities and analysis.

  • T V K RAJU Bharatam added an answer in Chemical Engineering:
    What is the best available (economical) method of ammonia production?

    See above

    T V K RAJU Bharatam · FREELANCER

    economically best method for ammonia shall be same as the best(economical) method to make hydrogen. 

  • George Stoica added an answer in Measure Theory:
    Is there any use in constructing/defining integration over (some subset of) the rationals?

    I was working on 2 papers on statistics when I recalled a study I’d read some time ago: “On ‘Rethinking Rigor in Calculus...,’ or Why We Don't Do Calculus on the Rational Numbers’”. The answer is obviously trivial, and the paper was really in response to another suggesting that we eliminate certain theorems and their proofs from elementary collegiate calculus courses. But I started to wonder (initially just as a thought exercise) whether one could “do calculus” on the rationals and if so could the benefits outweigh the restrictions? Measure theory already allows us to construct countably infinite sample spaces. However, many researchers who regularly use statistics haven’t even taken undergraduate probability courses, let alone courses on or that include rigorous probability. Also, even students like engineers who take several calculus courses frequently don’t really understand the real number line because they’ve never taken a course in real analysis.

    The rationals are the only set we learn about early on that have so many of the properties the reals do, and in particular that of infinite density. So, for example, textbook examples of why integration isn’t appropriate for pdfs of countably infinite sets typically use examples like the binomial or Bernoulli distributions, but such examples are clearly discrete. Other objections to defining the rationals to be continuous include:
    1) The irrational numbers were discovered over 2,000 years ago and the attempts to make calculus rigorous since have (almost) always taken as desirable the inclusion of numbers like pi or sqrt(2). Yet we know from measure theory that the line between distinct and continuous can be fuzzy and that we can construct abstract probability spaces that handle both countable and uncountable sets.
    2) We already have a perfectly good way to deal with countably infinite sets using measure theory (not to mention both discrete calculus and discretized calculus). But the majority of those who regularly use statistics and therefore probability aren’t familiar with measure theory.

    The third and most important reason is actually the question I’m asking: nobody has bothered to rigorously define the rationals to be continuous to allow a more limited application of differential and integral calculi because there are so many applications which require the reals and (as noted) we already have superior ways for dealing with any arbitrary set.

    Yet most of the reasons we can’t e.g., integrate over the rationals in the interval [0,1] have to do with the intuitive notion that it contains “gaps” where we know irrational numbers exist even though the rationals are infinitely dense. It is, in fact, possible to construct functions that are continuous on the rationals and discontinuous on the reals. Moreover, we frequently use statistical methods that assume continuity even though the outcomes can’t ever be irrational-valued. Further, the Riemann integral is defined in elementary calculus and often elsewhere as an integer-valued and thus a countable set of summed "terms" (i.e., a function that is Riemann integrable over the interval [a,b]  is integrated by a summation from i=1 to infinity of f(x*I)Δx, but whatever values the function may take, by definition the terms/partitions are ordered by integer multiples of i). As for the gaps, work since Cantor in particular (e.g., the Cantor set) have demonstrated how the rationals “fill” the entire unit interval such that one can e.g., recursively remove infinitely many thirds from it equal to 1 yet be left with infinitely many remaining numbers. In addition to objections mostly from philosophers that even the reals are continuous, we know the real number line has "gaps" in some sense anyway; how many "gaps" depends on whether or not one thinks that in addition to sqrt(-1) the number line should include hyperreals or other extensions of R1. Finally, in practice (or at least application) we never deal with real numbers anyway (we can only approximate their values).
    Another potential use is educational: students who take calculus (including multivariable calculus and differential equations) never gain an appreciable understanding of the reals because they never take courses in which these are constructed. Initial use of derivatives and integrals defined on the rationals and then the reals would at least make clear that there are extremely nuanced, conceptually difficult properties of the reals even if these were never elucidated.

    However, I’ve been sick recently and my head has been in a perpetual fog from cold medicines, so the time I have available to answer my own question is temporarily too short. I start thinking about e.g., the relevance of the differences between uncountable and countable sets, compact spaces and topological considerations, or that were we to assume there are no “gaps” where real numbers would be we'd encounter issues with e.g., least upper bounds, but I can't think clearly and I get nowhere: the medication induced fog won't clear. So I am trying to take the lazy, cowardly way out and ask somebody else to do my thinking for me rather than wait until I am not taking cough suppressants and similar meds. 

    George Stoica · Canada

    Dear Michael, statistics will not benefit from Cantor-like behaviour, that is true, maybe financial mathematics will, because the latter is always in search of better models. To see what I mean, and if you have time, take a look at an older paper of mine "Sufficient Poisson jump-diffusion market models revisited" - go to my RG page, or download from Proceedings of the American Mathematical Society vol. 130, 2002. pp. 819-824.



  • Elnaz Ghanbary added an answer in Pose Estimation:
    How do I define different postures of one plane with respect to each other?

    Hello every body.

    what is the simplest way to obtain position and orientation of two postures of one plate in space wrt each other, by knowing Cartesian information (x,y,z) of three points on the plate wrt a camera in each posture?

    for more explanation, we have a plate of one device e.g end effector of parallel robot, and we can obtain Cartesian information(x,y,z) of any desired point on it wrt camera(by stereo vision), the goal is to measure position and orientation of two postures of the plate in space wrt each other, I want to know ways to achieve this goal(especially simplest ones)? notice that we can put some markers on the plate,e.g one black paper with three white circle on it, or a triangle on the paper or...

     wrt=with respect to

    Elnaz Ghanbary · University of Tabriz

    Finally I found the solution:

    Least-Squares Fitting of Two 3-D Point Sets