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  • Niranjan Koirala asked a question in MTT Assay:
    Can anyone tell me the easy methodology to label flavonoids for the elucidation of anti-cancer activity pathway?

    Hello Everyone. I have been working in multiple modifications of flavonoids mainly glycosylation and methylation. We have recently set up an anti-cancer activity testing lab and we carry out MTT assays for several cancer cell lines. Recently we are interested to label active flavonoids and elucidate their binding model and signalling pathway inside the cancer cells. Anyone having experience in labeling technique please do let me know. Thank you.

  • Katara Jade added an answer in Developing Countries:
    In what diverse ways can qualification-inflation lead to the devaluation of the academic currency?

    In recent times, emphasis in education especially in developing countries has been placed on quantity of school products than on quality of the products. Schools at almost all levels are 'mushrooming' or springing up due to a desire to make education more accessible to many. In so doing, the tendency to sacrifice quality is a possibility. The consequence is production of a lot of so-called graduates without the requisite academic and social skills to change society.   

    Katara Jade · University of Tasmania

    Fascinating! I'm not in a position to enter this argument, but can see the two different perspectives, James' diagnosis of the system issues, and Erasmus' faith in the transformative ability of an interested and engaged educator, have decided to disengage from the conversation.

    Could I encourage you to continue? Respectfully and keeping to the topic of course.

    James, could I encourage you to answer Erasmus' questions: What do you do when a seemingly lost, low performing student shows up for your class. Do you have time for that kind of student, or you just allow yourself to lapse into a blame mode,  and move past the poor soul, leaving them contending with their predicament? How do you respond to students whom you believe did not get basics from the public school system? It seems to me that, whether you like it or not, these circumstances are turning up to your lecture hall or tutorial room. By proximity, you are making decisions regarding these circumstances regardless of whether this is your role or not.

    Erasmus, to provide context to your statements about the role of educators, could you perhaps elaborate on your view of the education system and what it requires back from educators to keep the system running? Is James' assessment of the current state of affairs justified, or perhaps justified within particular localities?

    Anthony may like to reengage in the conversation too.

    Looking forward to further comments.

    ~Katara

  • Samir Ghosh added an answer in E.G:
    What techniques can be used to extract Indium Sulfide flakes?

    Hi, I am doing a research on deposition of Indium Sulfide on various substrates(e.g Silicon, glass). I was curious to know how to extract the flakes of Indium Sulfide from the substrates surface.

    It would be really helpful if anyone could suggest me with any techniques to extract Indium Sulfide flakes.

    Samir Ghosh · De Montfort University

    @Ali, Thank you very much for being kind enough to suggest me. I really appreciate your help. I will try to follow your process and hope it works. Whatever is the outcome of the process I'll discuss here soon.

    Yes, flakes formation does not require any specific substrate which you are right. Yes there is a relationship and In2S3 forms tetrahedral nano crystals.

    Thanking you once again.

  • Is there any relationship between Vitamin D3 levels and pigmentation?

    UV rays and pigmentation are well known. Recent advances have pointed out to levels of Vitamin D3 and skin inflammation. Are they significant in causing pigmentation? 

    Anne von Koschembahr · University of Cincinnati

    Most papers focusing on pigmentation and vitamin D either look at one of two subjects:

    1. Effects of vitamin D on facultative skin pigmentation following UV exposure. Some groups have focused on this in vitiligo patients.

    2. Others have focused on vitamin D production in various skin pigmentary phenotypes following UV exposure.

     
    It sounds like you are trying to look at the first subject I listed but I am not sure. Can you explain a little more please?

  • Michael Peck added an answer in Space:
    Is there more than one theory of gravity that can demonstrate compatibility with the Einstein equivalence principle?

    I am looking for theories that give different observations, i.e. that are measurably different.

    • Observations must match Minkowski space in free space.  This is a theoretical question.  Not looking for radical theories that would violate Minkowski space.
    • Each theory must be able to demonstrate that observations in an accelerated elevator in free space are the same as in an elevator sitting on a planetary surface.
    • Please show how multiple elevators over an extent of space are integrated to give the different observations of each theory, i.e. how the same local observations integrate differently.

    Luca,
    I think maybe some aspects have drifted from the original question, but most of what is now being discussed are the details of various aspects. For example, it isn’t just about having other theories that are in agreement with Einstein’s equivalence principle, but also differentiating between such theories through measurements. My main focus was on per particle microscopic solutions and how the metric relates to that of a charged particle in the Maxwell-Einstein vacuum solution. Beyond possible insight as to why the stress-energy tensor may not be applicable to a metric field theory, I suppose everything about a unified field theory and vacuum energy density can be ignored in these regards.

    Nonetheless, I would like to point out that there is something rather significant in achieving equivalent first order gravity with respect to Einstein’s field equations and the relation to the metric of a charged object. In EFEs, it is assumed that no matter how much mass or particles exist in an object, the gravitational potential of the object follows distance as defined by the metric (even if there is only a single particle). This is by definition the strong equivalence principle as applied to a continuous source term, i.e. a stress-energy tensor. However, on a per particle basis, the gravitational potential of a single particle follows distance as defined by a Minkowski metric (or if other particles exist, the space-time metric induced by their presence). This is the meaning behind the φA terms. For weak field limits this does not add up to much; but when you get on the order of “black holes”, EFEs begin to fail. Thus the central point  I would like to focus on is that microscopic general relativity is not in agreement with macroscopic general relativity when applying the equivalence principles. This is measurable through future tests of event horizon and direct detection of gravitational waves.

    ds2 = -A2dt2 + B2dr2 + C22
    Reissner-Nordstrom metric (A = B-1, C = 1):
    A2 = 1 – 2φ + [ φ (keQc2/MG) ]2

    Single particle (A = B-1 = C-1):
    A2 = 1 – 2φA + [φA]2 = (1+φ)-2

    Dr. Kassner,
    Coordinate singularities never occur in my formulation unless infinite energy exists, so there is no need to make such transformations in the first place. The assumption that the Schwarzschild metric has bad coordinates is a personal preference and does not change the fact that it has an equivalent definition of gravitational potential with respect to my formalism.

    “It will evolve until the horizon and it will disappear from view then.” My point was that by the time it reaches the location of the event horizon in local proper coordinates (even if the event horizon does not exist in such coordinates), the event would take place after an infinite amount of time with respect to outside observers and thus is not casually connected with the outside universe.

    Assuming that gravitational potential as I have implemented them are not fully physically interpretable however is wrong. Gravitational potential is a component of the post Newtonian formalism and thus when determining PPN parameters for EFEs, time and spatial components are never mixed. There are many ways to view general relativity, but my aims are to take all aspects into consideration. I believe that if you actually consider what I am saying about per particle solutions and the problem with apply a classical stress-energy tensor, then it will become clear that my argument is not based upon a misunderstanding but perhaps a better understanding than most.

  • Behnam Farid added an answer in Band Gap:
    Optical Band Gap (Tauc Plot) and Superconductors, does Tauc Plot make sense to be plotted?

    I would like to ask if it makes sense to make Tauc Plots (either Direct or Indirect band gap ones) for a material that the literature claims to be a superconductor.

    Supposing that I had obtained a reasonable value (about 1.5 eV) for one of the type of Tauc plot. What would be the meaning of this band gap obtained? Is it still the gap energy between valence and conduction band?

    Some additional information: I got the Tauc plot from absorption spectra of a suspension of the material, at room temperature. And the critical temperature for this superconductor according to literature is about 4.4 K.

    Thank you so much for your attention

    You are welcome Alexandre. Regarding photo-emission spectroscopy, see the review article by Damascelli et al., the link to which I attach below.  Regarding optical gap and the attendant issues, see the book Many-Body Aspects of Solid State Spectroscopy, by M. Balkanski (Elsevier, Amsterdam, 1986). For excitons and excitonic effects, see the book Principles of the Theory of Solids, 2nd edition, by J. M. Ziman (Cambridge University Press, 1972); see in particular Sec. 6.7 herein.

  • Can we use fungi as biological control agents?

    I utilized certain species of fungi as biological control agents but I found that one of these species increased reproduction (egg laying) of the pest at higher concentration while it was more effective at lower concentration

    Stanley Dimkpa · Rivers State University of Science and Technology

    Hello Marwa,
    Your answer is yes but very broad as the establishment, development and sustainability of fungi in the field is greatly influence by climate. I think your best is to study the preparation of Bauveria bassiana as suggested by Andras Bozsik and also Metarhizium anisoplia. Oilbased formulation of B. bassiana in Burundi, Uganda and most other African countries against the sweet potato weevil Cylas puncticollis and banana weevil Cosmopolites sordidus have been incorporated in the integrated management of these pest.
    In 2004, I observed severe mortality of oil palm leaf miners, Coelaenomenodera lameensis in Oil Palm field and further investigation using their supernatant on the beetles resulted in early motality of all the stages of the insect’s development with clear growth of the fungi. Proposal for proper isolation, identification, rearing and formulation of the causal agent as bio control was made but unfortunately funding was not secure.

  • Anyone can help me to find the solution for a problem regarding neuron-based non-linear PID control?
    And are there any similar examples?
    Enes Uğuroğlu · Istanbul Technical University

    Thanks thats all helped!

  • Sulav Shrestha added an answer in Dairy:
    What can be the highest milk fat level in dairy cows in post-milking samples?

    What can be the maximum level of milk fat in dairy cows if the milk samples are taken post-milking by hand stripping? I am getting up to 20%! I understand that the milk fat level tends to increase as the milking proceeds. But the value i am getting is terribly high. Is this possible? Taking milk samples through herd testing process using meters, where the milk samples can be equivalently drawn out of each quarter, is not feasible in my trial. However, i try to strip out milk equivalently from each quarter. Can anyone give me any feedback regarding the results i am getting?

    Sulav Shrestha · Massey University

    Hi Carmen, we send out the samples to LIC (Livestock Improvement Corporation) which is an authorized agency for conducting herd test in New Zealand. But i am not sure about the method they use. I even tried inquiring them, they said their machines and methodology were working properly.


    Thanks Alaa, but in my research scenario, doing fat measurement by any other method except sending it to LIC is not feasible.


    Hi Toby, so do you mean, the high percentage i am getting is reasonable? Can you help me with any references regarding tendency of getting such higher values? Any hormonal changes that support them? In my case, the values are diverse. Some of the cows are within the normal fat range while some are extremely high.

    Thank you.

  • Thomas Iwanicki asked a question in RNAse:
    How do you effectively eliminate RNase from plastic (e.g., 96-well microplate)?

    I am trying to cut down on lab costs by reusing my OptiPlate-96 Black 96-well microplates.  My fluorescence assay requires an RNase a incubation.  I have heard that RNase binds to plastic and is very difficult to eliminate.  Does anyone have a proven method for for eliminating RNase from plastics?

    Thanks in advance!

  • Makmur Saini asked a question in PSCAD:
    Are PSCAD / EMTDC Can the transmission to bus above 30

    I have tried but could not for the PSCAD program version  2.4

  • Abstract in Meta-analysis: To include or not to include.

    I am performing a meta-analysis and my search was extended to EMBASE.

    As part of the process i have retrieved a few abstracts that were included in some congress abstract books. The results of these congress comunication are non yet published as full papers, but still some data are potentially extractable from these abstracts and could be included in the meta-analysis.

    Should i include them and state it in the Materials and methods section?

    I know that they are a low quality evidence that could possibly bias the research but wouldn't it be worse to exclude something that could be counted?

    Thank you very much for your suggestions!

    Giammauro Berardi · Sapienza University of Rome

    And what would you use to assess quality of the study (abstract in this case)?

    I always used the New Castle Ottawa scale for retrospective studies. But in this case i guess that is not really applicable because you can't have all the information this scale requires to asses quality.

    Furthermore, what do you normally use to asses quality of prospective studies (RCT and non RCT)?

    Thanks again

  • Would you trust a distinction between intention and volition?
    In the attachment there is a paper by Zhu, where the author tries to distinguish the concept of intention from that of volition. I found this paper interesting but at the same time not very convincing. I did not find any biological grounding to this idea. What is your opinion about this topic?
    Damian G Kelty-Stephen · Grinnell College

    Hmm, I think that perhaps one way to rephrase Beatrice's thought here might be that volition is the capacity to choose whereas intention is simply direction of action. Organisms might direct their actions towards a goal of their own volition or they might do so under duress.

    The question might be how much an organism wants what it sets out to do. If you take a strict view of intentional actions as pure drive satisfaction, then there are only physiological imperatives seeking a sort of homeostasis. However, in more comfortable times with fewer constraints on free behavior--close to what the psychologists Timberlake and Allison called the "bliss point"--organisms may vary as to where they find this bliss point with different activities.

    We all have to pay our bills, but we can decide when and how to do so. We all have the same intention when signing the check, but we'd probably rather keep the money. Paying money to a specific recipient is extremely intention, in the very explicit terms of directing a signal in a specific direction. So, that's intention without volition, except for volition in how we go about doing things we need to. At the same time, we may spend our money how we choose with what we have left over, bringing volition into the same intentional action of spending money.

    And I suppose there's also volition with out intention. We might fantasize or imagine things that are not the case or plan to do things that we do not have sufficient motivation to.

    So, yes, I suppose I can trust a distinction between volition and intention, but I can understand how it may seems suspect on first glance.

    Best wishes,

    Damian

  • In the absent of a rainfall simulator, how can you measure soil erodibility in situ?

    Field experiment.

    Sayjro Kossi Nouwakpo · University of Nevada, Reno

    I have never used the Jet Eorsion Test device before so I am not very familiar with its intricacies. I can however imagine using some form of regulated pump or constant head system with adequate water supply to implement the JET in the field. I believe this has been done in the past. If supplying enough water to your field site(s) is logistically impractical, you may consider bringing intact cores to be analyzed in the lab.

    The fluidized bed method works really well on soils with moderate clay content (< 40%). You will have to design your own fluidization chamber since there is none commercially available and I will be more than happy to assist you with that. I refer you to these publications for more details on this technique:

    SSSAJ Volume: 76 Issue: 4 Pages: 1192-1196

    and the one attached.

    Cheers,

    SKN

  • Justin Lemkul added an answer in Buffer:
    Do we have the option to include dielectric constant while performing a molecular dynamics simulation?

    I want to run a simulation of my protein at a particular pH and also wants to include dielectric constant. The dielectric constant  has an impact on binding even if I vary dielectric constant with the use of different buffer systems keeping the molarity constant and also keeping the pH the same for both the buffer systems. Does the dielectric constant have an influence in the stability of a structure significantly?

    Justin Lemkul · University of Maryland, Baltimore

    Adding an ion (assuming you mean hydronium) does not change the pH in a simulation.  In the absence of true titration (i.e. a changing topology), the concept of pH is ill defined in classical MD simulations.  Besides, if you add one hydronium to a typical simulation cell, you've (on an extremely simplistic level) modeled a concentration reflective of pH = 1 since the box is so small.

    You can, of course, do simulations in different solvents.  People do this routinely.  The key point here is that in explicit-solvent MD simulations (regardless of what that solvent is), the dielectric constant is not an independent variable; it is a fixed property of the model(s) used in the simulation.

  • David Ian Leavesley added an answer in Cells:
    What experiments can evidently exhibit the change of cell attachment ability?

    How to detect the change of cell attachment ability?

    David Ian Leavesley · Queensland University of Technology

    This question has been addressed previously in many ways b y many people. Go back to the literature from late 80's and early 90's; search for 'attachment assays'. Else you can buy assay kits from the major providers.

    In short they all measure 'detachment' of cells when subjected to a force (usually fluid shear). What you quantitate is up to you and your resources, however, usually people measure the number of cells remaining after being subjected to the 'force'. This is readily performed using vital dyes, manual counting, radioisotopes, fluorescence, etc. Adjusting the force you apply (impossible to do manually) will provide you with a measure of differential cell 'attachment'. 

  • How do you estimate the Long-term multiplier and Speed of adjustment from the vector error correction model

    I am currently working on a paper that requires me to get a measure of  Long-term multiplier and Speed of adjustment and then find out how some factors between the two integrated market after them

  • Francis Tsiboe added an answer in Cointegration:
    What are the steps involved in establishing that two markets are cointegrated?

    I am currently working on a paper that requires me to get a measure of cointegration and then find out how some factors between the two integrated market after the measure of cointegration.

    Francis Tsiboe · University of Arkansas

    Thanks Mounir that was very helpful. by the way how do you estimate the Long-term multiplier and Speed of adjustment from the vector error correction model. thanks

  • Does anyone know of any studies that have been done in Australia about the impact of boarding schools for remote Indigenous students?

    I've been able to find a lot of international literature, particularly North America on boarding or residential schools but not a lot from Australia.

  • Evan Chiswick added an answer in ELISA:
    Increasing ELISA sensitivity

    I am performing ELISA for human TNF-alpha in serum samples (stored at -80oC). The Abs and recombinant protein (for standard curve) I use are purchased from eBioscience (paired match). The thing is I need a higher sensitivity (~8pg) and till now I have fairly reached 125pg (curve starting from 1000pg, dilutions 1:2).
    Protocol I follow:

    • coating buffer NaHCO3 (pH 9.5) or PBS (no significant difference)
    • 96-microwell plate (tried different companies, still no significant difference)
    • dilutions of 1st & 2nd Abs according to the manufacturer (tried several matches, no result)
    • incubation time: O/N for 1st Ab at 4oC, 1 hr blocking at RT, 2 hrs for samples at RT, 1 hr for 2nd Ab at RT

    (the rest steps are typical for any ELISA assay I perform including washing, streptavidin and fresh HRP and standardized several times)


    I have also performed ELISA assay using Abs from R&D systems for TNF-alpha and to my great disappointment they didn’t work at all.
    Anyone used Abs (eBioscence or R&D) for TNF-a before? Any ideas to increase the assay’s sensitivity?
    Any ideas greatly appreciated!!

    Evan Chiswick · Boston University

    I agree with Serafeim, increase the length of your incubations. Also, I think it is odd that changing the dilutions of coating and detection antibody did not have any result. Increasing coating concentrations usually increases sensitivity, as does increasing detection antibody (although that may lead to increased background). Also, try different blockers. Pierce sells a streptavidin;HRP polymer that is supposed to increase the sensitivity (i.e. 25 HRP molecules attached to each streptavidin, versus 4 )

  • Gustavo Alvarez Colombo added an answer in Laptop:
    Is anyone aware of software that can run on modern laptops that can be used to control a Simrad EY500 scientific echo sounder?

    I am trying to resurrect an old split beam system.  The original system ran in DOS off of a select few Toshiba and other laptops.  They still work, but run in WIN95 without USB ports that would make data transfer for processing etc. easier, plus they look pretty unscientific.  Has anyone developed newer software for data acquisition that can be used with these old acoustic systems?

    Gustavo Alvarez Colombo · National Institute for Fisheries Research and Development

    Dear Kyle,

    I have asked Dr Helge Balk about that in the past. They have posted a quick recipe in there page (http://tid.uio.no/~hbalk/sonar4_5/index.htm), which you find below.

    We still haven't tried it, so please if you succeed, I will appreciate to have your comments.

    best regads,

    Gustavo

    How to run EP500 on a windows XP computer with 100 GB hard disks or more

    We have been running our EY500 with various PC's with both win98 and win xp and we have helped other doing the same. This enables the use of multiple large disks. E.g. three 200GB disks
    • Start by uninstalling everything.
    Then
    • Install DOS 7. (You can produce a DOS floppy disk on a win98 PC with FDISK.exe)
    • Partition your C-disk so that the C-partition is no more than 2GB. D-partition can be the rest of the disc.
    • Install EY500 software ver. 5.3.3 or newer
    • Install windows (98 or XP. we have not tested win 2000, but it will probably work as well)
    Remember to use FAT32 file system.

    This should be it. If you run into any problems please contact me or rather our IT expert Ragnar: email Ragnar.holm@fys.uio.no . I will anyway have to ask him since he is the expert that developed the procedure.

    Dr .H.Balk 10.03.2005

  • Stefan Gruner asked a question in Mind:
    Is Control-Knowledge the Strongest Form of Knowledge?

    Many years ago, when I was still a student, one of my professors occasionally said that we would have only then "really understood something", if we would be able to /implement/ "it" technically or algorithmically.

    In more philosophical terms, the professor's aphorism amounts to the question whether Control-Knowledge (or: Instrumental Knowledge) is the /strongest/ and /deepest/ possible form of knowledge, or ---even more bold and radical!--- if Control-Knowledge is perhaps even the /only/ epistemic entity which truly and rightly deserves the label "Knowledge" at all?

    Or, more concisely: What is the right understanding of "Understanding"?

    This difficult question I would like to discuss with Epistemologists, Gnoseologists, Hermeneuticists, Philosophers of Science, and Philosophers of Mind.

    [18-Sept-2014]

  • Can anyone suggest me which software is best for cell biology drawing?

    I want to draw some biological process as well as cellular differentiation and development. From which software I will get more benefit, please let me know....  

    David Ian Leavesley · Queensland University of Technology

    I have always found a pencil in my own hand is best!
    It is also the cheapest!

  • F. Leyvraz added an answer in Quantum Field Theory:
    Does quantum field theory resolve the measurement problem in quantum mechanics?

    Recently I read a paper titled "Quantum field theory solves the problem of the collapse of the wave function" by Alexey V. Melkikh (arXiv:1311.0205v1 -
    quant-ph). An earlier paper on the same topic is " Measurement problem in quantum mechanics" by Michael Danos & Tien D. Kieu (Int. J. Mod. Phys, vol-8, p-257, 1999). Both these papers claim that the measurement problem is completely resolved with in the framework of quantum field theory because it incorporates both the particle and wave aspects, while quantum mechanics deals only with the wave aspect. While the arguments in these papers are convincing, I would like to know the general consensus on this topic.

    F. Leyvraz · Universidad Nacional Autónoma de México

    I give up. But since you claim to have a mathematical difference, show it! In formulae, not in metaphysical words. A current is a current, it does not matter---to the mathematics---whether you choose to call it quantum or classical. The Schroedinger equation obeys a continuity equation in classical c-number terms. I hve shown this to you. Do you find an error in the proof or do you agree that there is a c-number continuity equation? I do claim that the answers of Bohmian mechanics are the same as QM, as far as the distribution of position of the particle (for all times) is concerned. In fact, I do not claim originality: this is just a rephrasing of things Bohm and many others have said. The continuity equation can be found at the beginning of Landau's Quantum mechanics. The proof is general, therefore your counterexammle must be wrong, though calculating it in detail will be hard

  • Krzysztof Herman added an answer in Herpetology:
    I'm revising the Pseudopaludicola genus based on its bioacoustics. Could someone help me with recorded calls?
    Advertisement call of Pseudopaludicola species.
    Krzysztof Herman · Wroclaw University of Technology

    What kind of help do You need? Data analysis, features extraction ?

  • István Lénárt added an answer in Geometry:
    What are your thoughts on the Yff center in limit triangle?
    here we find a new property of the Yff center in limit triangle such that the triangle degenerate to a pair of oppositely parallel lines, and we use the property of its excircles to get this new idea.

    our procedure is :
    1. we use the property of excircle to get a relation between the sidelines of the triangle and the tangent lines of its three excircles, and six tangent line altogether (page 3 formula (7))

    2. we introduce the trigonometric function :
    $cos^2{x}+cos^2{2x}+cos^2{3x}=1$
    to transform our triangle to limit case, that is a pair of oppositely parallel lines intersect at infinity.

    3. use the property of Yff center to study the height of the triangle (page 4 figure 1.4 )
    see: Page on wolfram.com. also note that the height of triangle and the three Yff lines divide every sideline $a,b,c$ of the triangle into 3 parts $t_{i},l_{j},l_{k}$

    then ,by step 3, we can represent the size ratio between a sideline of the triangle and the two tangent lines to one of its excircle which are also on the extension of this sideline.
    (page 6 formula (34) )

    lastly, by this ratio we get above and apply the barycentric coordinate of Yff center we can get a relation formula about the Yff center in limit triangle, such that :
    $cos^{2}{\frac{B}{2}}=\frac{9b^2(s-b)^3}{s(s-a)(s-c)}$
    where, $s$ represent the semiperimeter

    for more detail, you can go to :
    Application of the Ptolemy Theorem (1) (page 1-7)
    István Lénárt · Eötvös Loránd University

    Just an additional thought to your impressive and correct demonstration: As a sphere maniac (obsessed with spherical geometry), I tried to find an extension of the Yff center concept to the sphere. The condition about finding four congruent triangles cannot be applied for the general case because of lack of parallel lines. However, another condition may replace congruence, namely, the four triangles should be of equal measure of area. Taking a regular spherical triangle with three right angles, my experiments show that a central regular triangle with angles about 64° yields three 'corner' triangles with the same angles. In this exceptional case, congruence is also fulfilled for the four triangles. If this idea works, probably it can also be extended to the hyperbolic case.

  • Is it possible to apply matched field processing to engineering applications?
    I am interested in localizing an underwater sound source in ocean surveillance area. Maybe it's possible to use matched field processing since it takes account of acoustic propagation in the ocean to reach high precision. But the algorithm is too complicated to run on a DSP. I wonder if it's possible to use this method in recent years.
    Krzysztof Herman · Wroclaw University of Technology

    What about array processing, sparse matrixes and robust  algorithms based on signal subspaces methods?

  • Sindre Lee added an answer in Bioinformatics:
    How can I deal with technical replicates in the cuffdiff?

    I have two sets of technical replicates and wanna see the differential expression using cuffdiff. Can you please tell me, an appropriate way to deal with these two (or more) technical replicates.

    Sindre Lee · University of Oslo

    If you just want to do gene expression analysis, I recommend edgeR or DESeq2.

    If not I guess the easiest way is to merge the bam files. Using Samtools or Picard.

  • Aurelio Sanz added an answer in Tissue:
    I find it difficult to focus the laser onto tissue surface with RENISHAW confocal Raman spectrophotometer. Is there a trick to focus quickly?

    I am trying to analyze the signature Raman spectra of the normal gastric mucosa tissue and gastric cancer tissue .The tissue was examined under a RENISHAW confocal Raman spectrophotometer with aHe-Ne laser, an excitation wavelength of 785 nm, a power of10 mW, an integration time of 10 s, a resolution of 1 cm-1
    ,arange of 400–2000 cm-1, and a 80x objective. I found it difficult to focus the laser onto the surface of tissue. The laser focusing step usually takes me an hour, and what I got is the Raman spectra of the glass holder. Is there a trick of focusing the laser onto the tissue quickly and precisely? Thanks. Besides,The gastric tissue is almost transparent .Is that the reason to focus the laser on to the surface diffcult?

  • Pablo Alexander Reyes asked a question in SPSS:
    In studies in fMRI, Is valid export the value of contrast obtain in marsbar(spm) to SPSS?

    What does them think about the obtained by MarsBar the contrast value for different rois and introduce this value in SPSS? (for correlations or comparison between groups)
    ¿is correct and reliable this approximation?
    Thanks!!!