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  • Kilyoung Kim added an answer in Iodine:
    How can I determine Iodine in Potassium Iodate?

    Dear all,

    Can someone help me to determine iodine in potassium idoate by UV, HPLC or titrimetric method. My product includes Zn, Cu, Fe and Mg with potassium iodate. And also it's concentration is very small, 0.06%. I tried much titrimetric methods and HPLC methods to determine this iodine but no result.

    Kilyoung Kim · Lipocine Inc., Salt Lake City, Utah, United States

    Try to use LC/MS if you only want to analyze iodine in potassium idoate.  If you want to analyze other metal elements with iodine, try to use ICP-MS.

  • Rocco Labadessa added an answer in Ecosystems:
    Which general traits define an ideal species group as model in ecological studies?

    Biologists use model organisms in their studies with the hope that new discoveries will provide insight in the features of the same species but also of other species that they are supposed to represent. This generalization helps to simplify their research. Such model organisms usually possess a specific trait that makes them easier to use in experimental set-ups. They may be easy to cultivate, such as in maize (Zea mays) or mice (Mus musculus), they may regenerate easily, such as shown by species in the genus Hydra, or they show a short life span, such as fruitflies (Drosophila melanogaster).

    Model species groups or so-called exemplar taxa can be used in ecological studies to clarify the structure of biodiversity by combining taxonomic, phylogenetic, and functional data as expressed locally in an ecosystem (α-diversity), among nearby ecosystems along environmental gradients (β-diversity) and in an area at a much larger, biogeographical scale (γ-diversity). The question is what properties would make a species group ideal as a representative subsample in biodiversity research. Should the model group be monophyletic? Should it represent 5, 10 or more % of the total number of species. Should it consist of generalists, specialists, or both? Should its species be easy to find and easy to identify for fast and clear results, or should they be obscure in order to be less affected by anthropogenic factors? The best answers may depend on the specific question, but maybe there are general features that define an ideal model group. Or is there not such a thing and should ecologists select species groups that they themselves are most familiar with? What is your favorite model species group and why?

    Rocco Labadessa · Università degli Studi di Bari Aldo Moro

    As you said, the best answer depend on the specific question.

    For example, some of the widely used indicator taxa, e.g., passerine birds or butterflies, can represent a good biodiversity subsample with regard to their wide diversity in species' ecology, behaviour, specialization and relation with habitat and landscape features. Higher diversity values in these taxa would generally indicate higher habitat diversity - thus usually meaning higher overall biodiversity.

    Other taxa, e.g., amphibians or grasshoppers, that are more strictly linked to a habitat type, would be more profitably used for studies of "within habitat" diversity.

    In any case, well known and easily recordable taxa would surely make the work easier.

  • Nurul Sarkar added an answer in Network:
    Does anyone have experience with Network Metrics:Throughput, delay and jitter?

    As I have calculated Packet Loss Ratio, now want to calculate throughput, delay and jitter in Wireless Body Area Networks (WBAN), can anyone tell me how should I proceed further? Thanks in advance

    Nurul Sarkar · Auckland University of Technology

    If you know delay (response time) then you can easily calculate throughput. For example, to transfer a message (or file) of size X (bits) from point A to B. If D is the delay in (sec). Your throughput would be X/D (measured in bits/sec).

  • Fatiha Chigr added an answer in Microglia:
    What is a good protocol for the BrdU staining in vitro of microglia?

    Hi, does anyone have a good protocol for double staining BrdU and a microglial marker such as OX-42 ?? or BrdU with Iba1? Thanks very much for your help Tanja

    Fatiha Chigr · Université Sultan Moulay Slimane

    The other way works also well. The pretratment with HCl do not generally influence the second  immunostaining.

  • Ulrich W. Bläß added an answer in PXRD:
    What are the possible structures of Cu doped Mn2O3?

    I synthesized some catalyst made of Cu doped manganese oxide. I found CuO and Mn2O3 peak in PXRD. So what are the possible bonding between Cu and Mn in the unit cell and what are the defects can be created? Can anyone tell me any suggestions about it, so that I can draw some intimidate structure for the coupling reactions with the catalyst?

    Thank you

    Ulrich W. Bläß · Technische Universität Bergakademie Freiberg

    The spinel structure is open to a wide chemical variability. If peak positions in PXRD are very similar to a mixture of Mn2O3 and CuO, i suggest that intensities still would be different - so again Rietveld could be the method to choose.

  • C.O. Gerçek added an answer in STATCOM:
    Is it possible to combine STATCOM and SAPF(shunt active power filter) in multilevel converters?
    So that it's able to perform tasks of STATCOM and SAPF (voltage regulator and harmonic eliminator). Can someone advise me?
    C.O. Gerçek · The Scientific & Technological Research Council of Turkey

    Dear liranican,

    Yes, it is possible, thanks to sinusoidal PWM technique and DQ transformations. As long as the harmonics (or interharmonics) that you would like to filter out are not close to the fundamental frequency, you may both make reactive power compensation (or terminal voltage regulation) and harmonic filtering at the same time with multilevel converters triggered with PWM, but not SHEM. You may also have a look at the articles in IEEE to gain a better understanding.

    I hope I could help.

  • Is anyone interested in Requirement Engineering (Pattern to Requirement Statements)?
    I am starting a RG Project to work through an example for developing an approach to using requirement pattern concepts, UML profiles, and a UML CASE tool to generate requirement statements.

    If interested please let me know, this will be open to anyone who wants to participate, or check on our progress,
    Paul Wren · University of North Dakota

    I worked on an effort to establish requirement patterns for avionics software, and found the following book to be useful:

    Software Requirement Patterns by Stephen Withall

    I realize this is only somewhat related to your efforts, but it may be a good resource.

  • Do ALL hermitian operators have real eigenvalues?

    In the standard proof showing that hermitian operators have real eigenvalues we exploit the  symmetry of the operators to show that they only have real eigenvalues.Does this hold for ALL hermitian operators in general?

    Carringtone Kinyanjui · University of Nairobi


     I agree,I don't understand nonolocality(who does?) but let's find out.In the same article the conclusion goes thus:

    "According to the principle, a pair of entangled quantum particles must be indiscernible from a single particle, since both objects have in common all the same properties—this is the only stipulation of the principle, number being irrelevant."

    Now,if,as the authors of the paper say  number is irrelevant,how comes your interpretation of single particle non locality is radically different from the interpretation of multipartite non locality?Why is the number relevant?

  • PPI Dataset

    Can someone tell some reliable sites for getting PPI(Protein protein interaction) datasets. I need for a Applying Machine learning techniques for a project!

    Any help will be appreciated!

  • Christopher Charles Rout added an answer in Variables:
    What is the difference between 'variable' and 'parameter' - da capo?
    One suggested answer to the question of difference between 'variable' and 'parameter' found on the net is:
    A variable in mathematics is a symbol that has multiple values, in other words the value of it varies depending on conditions.
    A parameter (usually t or u signifying time) is very similar to a variable in that the value also varies (but is normally defined as being within a certain area), however a parameter is a 'link' between two other variables.

    Now, what - in medicine - is Cardiac Output, CO: a variable, i.e. the value of it varies depending on conditions (you might say!), or a parameter, i.e. 'link' between two other variables - CO is 'linking' heart rate and stroke volume. And you may ask is heart rate a parameter or a variable, stroke volume likewise. Add to this that variables evidently can be dependent or independent.
    This introduces some variation of linear thinking which may not be suitable to the circulation, which as the name implies, is circular?
    Grateful for your thoughts on the subject....
    Christopher Charles Rout · University of KwaZulu-Natal

    a variable

  • Cecilia Lewis Kausel added an answer in Timber:
    Does anyone know of any research in European Medieval Timber Roof Structures?

    Searching any relevance or connection between the 15th-19th century wooden roof churches of Cyprus with relevant structures in Europe.

  • Pietro Pilo Boyl added an answer in Ligases:
    Ligation of big insert 8 kb into 6kb vector

    I facing problem cloning 8 kb insert (PCR product) into 6.5 Kb vector (plfn-DTA) , the problem i still have colonies from cip treated vector only after transformation. I did everything at 30 c and I used different ligation rations 1:1 1:3 1:6. I used Nzy ligase kit 16C O/N and super competent Dh5 alpha. Do anyone have any recommendation

    Pietro Pilo Boyl · University of Bonn

    Indeed for this type of cloning nowadays it is not worth spending time with the classical restriction/ligation approach. NEB Gibson Assembly or Clontech In-fusion approaches are very similar in principle, very convenient and very efficient.

    Anyway, since you happen to have background and I imagine no positive clones (I would imagine you have less clones in the ligation than using the vector only....), it looks like one of your RE is not efficient enough and you have too much single digested plasmid. Try buying a new aliquot of your enzymes, or change producer (Roche RE are quite reliable and efficient, although more expensive)... the restriction step is critical in classical cloning. The CIP treatment generally helps, but is never 100% efficient and does not solve completely the RE inefficiency. I suggest anyway using the Antartic phosphatase from NEB.

    Good luck

  • M. Farooq Wahab added an answer in Benzamidines:
    Polar compounds separation by HPLC - any thoughts?

    I have a polar compound (Benzamidine) and want to retain/analyze it by HPLC using Discovery C18 or C8 column. I tried many eluents (e.g., ACN, MeOH, EtOH, phsphate buffer pH 7, water) with these columns but could not seperate it. Is there any suggestions? Provided that polar compounds are difficult to retain by these conventional columns because they make an electrostatic bond with the stationary phase of the column.

    M. Farooq Wahab · University of Texas at Arlington

    Before we suggest different modes, what other columns (and chemistries) are available to you? Do you have a bare silica column?

    If a given column chemistry is not retaining something with many mobile phases, it is time to try a new column type and a different chromatography mode.

  • Arnold Trehub added an answer in fMRI:
    Are high-level visual areas sufficient for conscious vision? How does subjective vision gain holistic access to spatially distributed neural codes?

    I have a thought experiment (video link: "Paradox of Subjective Bilateral Vision"16:00-28:00) that results in very strange situations if "high-level visual areas themselves are not sufficient for conscious vision, (or low/mid-level visual areas are necessary)", namely, that the neural mechanism of conscious vision, its verbal report and solving of perceptual visual tasks (e.g. bilateral symmetry detection) violates physics that we know of today. I would like to know if there is any experimental/theoretical evidence on this issue. Thanks in advance!

    Thanks to the two contributors, the above question has developed into a discussion on how subjective vision gain simultaneous holistic access to spatially distributed neural codes. There have been claims that 'holistic access' should be considered as a serious constraint on the neural mechanism of subjective experience. In case of vision, the seamless and the unified nature of our bilateral percept can be thought as an indicator of our consciousness mechanism having holistic access to wide-spread neural representation.

    Unlike many popular theories of consciousness, some scientists believe that holistic access should be solved by actual physical processes in the realm of established science. In other words, there should be some single 'entity' that has causal physical access with consequences, to all subjectively experienced information. Although, there are surprising small number of models on consciousness that actually implement such a mechanism.

    I explain my "Chaotic Spatiotemporal Fluctuation" hypothesis in the linked video (40:00 - 50:00), where holistic access is implemented by deterministic chaos components in neural fluctuation. Here, I define holistic access as 'every local change in the distributed neural code evoking global system-level changes in neural fluctuation', which relies on the so-called 'butterfly effect' of deterministic chaos. For the sake of clarification, the link between 'holistic access' and 'subjective experience' goes beyond physics that we know of today.

    I would very much appreciate comments on the first question too.    

    Arnold Trehub · University of Massachusetts Amherst


    If you take "conscious experience" to mean the phenomenal content of consciousness, I maintain that all such contents are decomposable, multi-featured neuronal patterns/images; specifically, they are representations with features that can always be analyzed and compared to other phenomenal representations. This is not the case with propositions because propositions are only symbolic tokens that "point to" multi-featured patterned content. In my synaptic matrix model, class cells are propositional tokens, and the patterns of activation on the mosaic cells are images that can become conscious if they are back-projected into our egocentric retinoid space where they represent something somewhere in relation to our self (I!). Propositions can selectively point to images of all sensory types, but they, as such, are not part of our conscious experience even though they may evoke the conscious patterns of inner speech. Does this clarify the distinction?

  • C.O. Gerçek added an answer in Power Systems:
    Can anyone explain why this system has a waveform like this?
    I designed the distribution system to identify the effect capacitor bank on power quality. The capacitor initially open and closes at 0.4s.
    C.O. Gerçek · The Scientific & Technological Research Council of Turkey

    Dear Muhammed,

    I suggest that you use a series combination of L and R as the source impedance for representation of distribution level. If you know the short-circuit current or power of the network before your connection (i.e. Thevenin equivalent), then just calculate X from this information (X = V*V/SCMVA or X = V/(1.732*Isc). Then find L = X/(2*pi*50). You may take R = X/10 for distribution in practice. If you do not know the SCMVA of the distribution level, try taking it 2000 MVA. This is a reasonable value when your capacitor power is considered. One needs to know the P+jQ loads and the transformer power rating also, though. By the way, most of the time the impedance of the transformer will dominate and the source impedance will be negligible.

    Let us know about your progress please.

  • Satyabrata Sarangi added an answer in Spartan:
    Can any body tell me how to implement arctan using vhdl code in fpga?

    I am working on spartan 3e fpga board.for my project i have to implement resolver that need arctan.can anybody tell me concept for doing that.

    Satyabrata Sarangi · IIT Kharagpur

    Hi Anjeet,

    You can implement arctan function by a CORDIC block operating in Vectoring mode. It's a pretty interesting segment of CORDIC.  You just check this document, http://www.andraka.com/files/crdcsrvy.pdf. Once you are done with basics, go for efficient architecture design for the same, and finally write the Verilog/VHDL code for the same.

    I hope this helps you.

    Good Luck.


  • Jtim Tim Rainey added an answer in Dental Caries:
    Where can I find information concerning development of salivary glands in the upper lip of infants?

    This is very important in understanding the development of early pediatric caries.

    Jtim Tim Rainey · Texas Institue for Advanced Dental Studies


  • Jerry Rhee added an answer in Replication:
    All phenomena are unique in perceived physical expression: what are the potential consequences for the definition of 'replicated' science practice?
    Philosophers or scientists aim to define unifying theories to explain as much as possible numerous phenomena based on a few principles. Philosophers might for instance state that two phenomena separated in time or space always differ in at least one scale of analysis or perception. Individual particles, like bosons or fermions, might be unique immeasurable physical expression because of Heisenberg principles. Physical expression combining these particles at higher levels of organisation should therefore also be unique in physical expression. Thus, two grains of sand on a beach or two oxygen atoms might never be structurally exactly the same at all scales of analysis. In addition, because phenomena will probably be perceived differently by organisms with different biology, philosophers might state that for at least one scale of analysis two phenomena will never be perceived exactly the same by different observers. Because phenomena might be material, objects or living beings all these philosophical statements would cover any spatiotemporal scale in distinct science disciplines, including Physics, Chemistry or Biology.

    This would imply that physical, chemical or biological structures are physically always 'un-replicable' or perceived as 'un-replicable. Are 'replicable' phenomena as defined in science practice not more than human mental products disconnected from the true nature of nature? Scientists might for example accept 'imprecisions' when they define classes or groups of phenomena with common characteristics to make them 'replicable'. Do scientists invent artificial rules to make science practice workable from an empirical or mathematic point of view?

    Peirce talks about consensus opinion "fated to be agreed upon by all who investigate".  Therefore, it depends on what you mean by consensus and the difficulty of changing opinions in reality. 

    97% of scientists agreeing on whether man is causing climate change means that there is consensus to those who believe (who would call it truth).  To the 3%, it means that there isn't a consensus (who would call it opinion).  Regardless of which, the important matter to those who investigate is NOT whether there is or isn't a consensus.  The part that matters is the values they have that influence the choice to believe or not and whether an argument can be constructed so that others will also believe. 

    This is one example of embeddedness and it also gives an idea of how steering consensus opinion can be outside of ourselves.  But this doesn't necessitate that current consensus is the consensus at the limit. Something may happen tomorrow to push that number higher or lower, like your house burning down because of drought.  An important matter is whether we are willing to act on that belief.

  • Are there any protocols in your country for interviewing minors who are victims or witnesses of any form of abuse?
    I am seeking information so as to improve the current protocols that are employed by police and legal authorities in Greece.
    Emmanuel Didier · Government of Canada

    Look atr the website http://psychotemoins.inist.fr/, which deals exclusively with that issue.

  • Herbert Weidner added an answer in Grounding:
    In piezoelectric devices modules, what's the difference between Ground and Roller?

    Dear everyone, please give me a reply, thank you.

    Herbert Weidner · Fachhochschule Aschaffenburg

    Do you mean Roller screw? That is shown in wikipedia. But what do you mean with Ground?

  • Which real-life optimization problems are multi-modal?

    We have developed a new heuristic specifically designed to deal with multimodality. Although it has performed well on benchmark functions, we are looking for real-life optimization problems to test it. If possible, please include references to publications where the problem is formally defined and its multi-modality explicitly stated and analyzed.

    Antonio Bolufé-Röhler · University of Havana

    Dear Ioannis,
    I agree with you that all global optimization methods have implicit mechanisms to escape local optima and thus dealing with multi-modality. However, I also believe that many of these methods were designed to perform well on both, unimodal and multi-modal problems. Furthermore, some heuristics such as Particle Swarm Optimization were initially tested (and designed) using unimodal functions. This could be the reason why initially they used a global topology and later recommended to use a ring (local) topology – “Defining a standard for PSO” paper.
    I also believe this is the reason why so many explicit methods for increasing diversification and exploration exist (e.g. niching methods). But in most heuristics these are ad-hoc techniques. Conceived after the design of the (meta)heuristic, or the deterministic algorithm. In our heuristic we took these considerations into account from the beginning. That’s why I stated that it was specifically designed for multi-modal optimization.
    Thank you very much for your answer (and all the useful references).
    Cheers, Antonio

  • For the treatment of anxiety and depression in cancer patients, which is more appropriate: mindfulness or behavioral activation?

    Usually both psychological treatments are used for cancer patients, especially breast cancer. In your opinion which of them can be more effective and longer term impact?

    Patricia Fobair · Stanford University

    Let me refer you to:  www.copingengine.com. It's an interactive website that allows the user to identify their negative feelings, negative coping, (yes 'we' contribute to our anxiety and depression with our unhelpful coping techniques like 'blaming,' and then moves the user to choose one of many active coping choices that can move them towards a happier outcome... Behavioral approaches help with self recognition, and choosing new adaptive choices....

  • Is it possible to generate electromagnetic wave without coil and just using oscillator IC ?

    I has been done my research to look the effect between electric field and dielectric substance. I use oscillator IC to generate the oscillation of electric signal, and connect it to electrode. I hope the electric field present there. Is that possible the magnetic field also present there too? Because, when i put the other electrode near it, i see the attenuation of wave after propagating the air. Is that electromagnetic wave ? Whereas I  not use coil in generating the wave.

    Herbert Weidner · Fachhochschule Aschaffenburg

    A Gunn diode generates EM-radiation without L or C or a cavity. The frequency is determined by the length of the crystal. Both electric and magnetic fields propagate as usual. In the near field, both are much stronger than in the far field. The phase difference between E and M component is zero in the far field, but not in the near field.

  • Costas Drossos added an answer in Co-authorship:
    Does co-authorship lead to more scientific researches?

    Co-authorship aimed at inducing collaboration between authors, increasing their productivity, and improving the researches quality. What is your opinion?

    Costas Drossos · University of Patras

    Co-authorship, is great provided that the co-author is the appropriate one. I had negative experiences as well.

  • Sujit K. Biswas added an answer in High Voltage:
    How do I measure the high voltage pulse current?

    Pulse current, high voltage, rise & fall time 1usec 100hz, pulse current transformer.

    Sujit K. Biswas · Jadavpur University

    Dear Anil, please clarify if you need to measure voltage or current or both. Note that only the voltage can be 'high voltage' and current cannot be so. If I assume that one terminal of your source is grounded, then current measurement will not involve high voltage isolation needs also.

  • N. Beithou added an answer in Building:
    Are PV systems practically feasible for residential buildings?

    Some people complain for its practical short life.

    N. Beithou · Applied Science Private University


  • Can anyone assist with an ID of this organism please?

    The images show a Cladophora-like mat that forms a biofilm in a brine RO system.  The sample was collected from cartridge filters processing 1.4% brine.  The filament branching is typical of Cladophora, as are the cell length to diameter ratios, but the overall cell sizes are smaller than those for freshwater Cladophora.  The biofilm occurs as a thick white to yellowish exudate.

    Carlos Guillermo Vélez · University of Buenos Aires

    Arthrospore-like conidia seem to be obvious in fig. BrineBiofilm007,, and a budding (?) yeastlike state in fig. BrineBiofilm003. Best!

  • Juan Gómez Gerique asked a question in Composition:
    What should the density of the LDL to be regarded as small and dense?

    Often are references to small dense LDL as highly atherogenic LDL, in what range of densities that LDL must be considered to be small and dense, and what its composition?