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- How can I prepare a cheap counter electrode for DSSC?
By replacing the platinum
is it conducting ? we want maximum conversion - we have enough poor conductorsFollowing
- Extraction of texture of an image by using GLCM method
I intend to use the method (GLCM) for extracted the texture features from Gray-scale image, but I noticed there are set of equations can be applied, such as the Energy , Contrast, Entropy, and so on and I do not know of any possible equations that can be achieved a high recognition. Thanks a lot for your help.
Usually, several statistical features are extracted from a set of GLCM. Namely the Contrast, Entropy, Energy, Correlation and Homogeneity. For better results, you can try to combine the GLCM with Run Length Matrix (RLM) or check the Local Binary Patterns (LBP). The best texture analysis method will depend on the type of images you are working with.
You can find a MATLAB code for the RLM here: http://www.mathworks.com/matlabcentral/fileexchange/17482-gray-level-run-length-matrix-toolbox/content/GLRL/grayrlprops.m
For the LBP, you can check the Oulu university page for papers and codes: http://www.cse.oulu.fi/CMV/Research/LBP
- Quinine and its derivates
I'm searching for another usage of quinine and its derivates from cinchona bark except as an antimalarialFollowing
- To What Degree Should We Tolerate, Cherish, and even Encourage Imperfection in Art, Architecture, Science, Literature, Law, and Music?
In his "Ethics," Benedict de Spinoza calls God perfect Being, whereas all other beings are imperfect. If this is so, then the creatures of human beings are even less perfect. Some artists, architects, scientists, writers, jurists, and composers prioritize some of their creatures over others and leave these others unfinished. They are imperfections to the fourth degree. The cultural landscape is littered with incomplete works. Why do their authors save them? Should we not get rid of them? If not, why not? What value can they have? Offer outstanding examples of incomplete works from world art, science, philosophy, architecture, letters, law, and music, or else from your own research and creative work of pieces that you did not bother to finish, yet kept in your desk or lab. Explain why the retention of all those works. When is it proper to get rid of any?
Determining when an art object is "finished" is a crucial step in the creative process for all artists. If one goes too far (or not far enough), the potential appeal of a piece may be lost (or never attained). The creative act often involves manually transferring one's mental image and state of consciousness to physical media. The point where one feels that this has been accomplished successfully can vary, and one's intuitive aesthetic response to one's own creation may or may not coincide with the aesthetic responses of other people. An honest artist will usually go with his own feeling.Following
- How would you distinguish Central Sensitization of pain (CS) from Complex Regional Pain Syndrome (CRPS) for injury-induced pain?
Both appear to involve allodynia, hyperalgesia. Do they both also involve reduced threshold for pain, peripheral and central hyperexcitability, recruitment of other sensory motor pathways, convergence and increased brain receptive field size for pain? What clinical features would you use to distinguish them diagnostically?
I am writing up a case report of manual therapy for what appears to be centrally sensitized pain and wonder if I can cite relevant literature from both topics? I am seeking to develop a hypothesis of the mechanism, since I do not find research on similar treatments.
I realize CS also includes whole body pain, such as from fibromyalgia, osteoarthritis, and pain not associated with peripheral injury such as migraine. I am specifically referring to injury-induced pain.
Thank you for clarification and any suggestions!Following
- How to reduce the time line stop due to part shortage from supplier.
One of main problem in assembly line is part shortage from the supplier due to quantity and quality problem.Following
- Antigenic shift in Ebola?
Since Ebola infects animals and humans, is it possible that one strain of Ebola merges with another strain of Ebola to produce a completely mutated new viral strain altogether?Following
- How to clone a 3.5 kb FL CDS of a gene?
I have to clone a gene in the range of ~3.5 from cDNA and i am having issues designing the primers using softwares. Basically i want to design the primers that can amplify full-length CDS (start-stop). Even though i input the FL CDS of the gene along with 50bp of UTR's in the primer design softwares, i am not getting the primers that will only amplify CDS completely. Any help please?
Hi Upendra, yes could be just the PCR is not working so well. You can try high fidelity DNA polymerase from Clontech. In my experience the choice of well working polymerase is critical. I am using Advantage® HD Polymerase Mix .
- I made a gel for RNA integrity that showed four bands, what is the mean?
As you can see in the image attached, there are four bands. Three are known (genomic DNA band, 28S and 18S rRNA bands), one is unknown. Do you know what is it?
Hi Pedro, I agree with Yordan. It can be tissue specific and also species specific. It looks like fragmented 28S.Following
- Does superconductivity persist in nanocrystals?
Superconductivity is essentially an emergent phenomenon of many body electron system. I am wondering how much size reduction can it stand. Certainly no superconductivity exists for a single atom or perhaps for even a small cluster of atoms. So superconductivty cannot persist indefinitely and has to disappear for some small size.
I would actually recommend the articles from Kalus Kern's group provided by Joachim above. I recall having heard Klaus speak on the topic some years ago and that was actually a good and quite convincing talk.
A link has been made above to the case of superfluidity. beatiful experiments exist on the rotational spectra of molecules solvated in small He droplets (T~0.37K). If I remember right one might want to atribute the term "superfluid" to objects as small as having less than 100 atoms!Following
- What is significance of Schrödinger equation in quantum mechanics?
I am confused for the time dependent and time independent Schrodinger equation.
There is a subtle not very well understood foundational problem here .That is related to the problem of time ordenation on the observables or even no propagator (see the Barry Simon book , I guess vol 2 ) .Even on the path integral formalism time dependent systems , one uses such time order operator ! .The point is that on non relativistic quantum mechanics , one always is interested to calculate transitions probabilities , specially the S-Matrix (time zero to time infinite )-It is interesting to call attention that the infinite set of the differential first order to the time dependent transitions coefficients in time dependent perturbation theory never received apparently a rigorous mathematical treatment .And about tunneling in the presence of time dependent perturbations ?.And time dependent spin interaction -The Pauli equation ?. And random external fields , how they affect the time dependent Schroedinger Pauli equation ?.Following
- Do you agree with Stephen Hawking's recent conclusion that black holes don't exist? Black holes don't exist. I published this many years ago. Cantor's Universe doesn't allow the concept.
Stephen Hawking now came up with the same conclusion. Read: http://www.spektrum.de/news/es-gibt-keine-schwarzen-loecher/1222059
In my opinion he is right this time. What is your opinion? Was he right then or is he correct now?
Although the Schwarzschild metric possesses a coordinate singularity, it is important not to forget that the surface r=2m does actually represent an event horizon. This is not something to be sneezed at! There is of course enormous freedom to select different coordinates but, whatever choice is made, the fact remains that the ratio of the rate of passage of proper time of a particle (of vanishing mass) approaching an event horizon relative to the rate of passage of time of ANY external observer (even one rather close to the horizon) moving in ANY direction and at ANY speed tends to zero. This can be easily proved from the metric.
If we disregard the bigger picture we can imagine some unwitting victim falling into a supermassive black hole without noticing any abrupt change at the event horizon (or even tidal effects) but the consequences for them would be drastic. For instance, whereas it is always possible to quantify the relative rate of passage of proper time of two clocks following arbitrary worldlines external to the event horizon (and obtain agreement using any coordinate system), it is impossible to do so if the two clocks lie on opposite sides of the event horizon (attempts to do so result in nonsensical answers). Mathematicians might ignore this warning but I don't think physicists seeking to describe our universe should. Why would a physicist choose a coordinate system adapted to a region of spacetime that cannot possibly have any influence on this universe?
Many textbooks (correctly) tell us that particles can reach the event horizon in finite proper time but then they often rush on to consider what happens to these particles "afterwards" without really pausing to think about whether there can be such a thing as afterwards (glossing over the infinite time dilation at the horizon and also the important question I sense that Otto was originally asking). Due to the teleological aspect of the event horizon (see e.g. Penna, http://arxiv.org/abs/1112.3638v1) and the fact that event horizons have been observed to form in computer simulations in regions of pure vacuum (see my previous postings for the reference) it seems highly plausible to me that gravitational time dilation ensures that realistic black holes remain forever hollow. Their event horizons would therefore represent physically impenetrable boundaries, much like the outermost surface of the (currently expanding) universe. This may seem to clash with the standard BH metrics (which possess singularities, closed timelike curves and other pathologies) but symmetry and stationarity was imposed from the outset when those metrics were derived - not obtained through allowing spacetime to evolve subject to the constraint of formation in finite time within this universe. I therefore regard the standard BH metrics not only as hypothetical but dangerously misleading. Real black holes do not have to devour matter through their event horizons in order to grow and, in any case, general relativity suggests they cannot do so. If anyone here knows of a counter-example then why not share it?Following
- 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?
ALL hermitian operators have real eigenvalues. This is a mathematical theorem without exceptionFollowing
- Does any know why Roche discontinues pyrosequencing? Purely marketing issue or there is technical issues with the technology?
Just realized Roche first stopped NGS research, then announced 454 platform support discontinues in 2016.
Is this just marketing issue or technological ones?
Looks like the tech has some advantages vs Sangers
Thanks. wondering how much the cost can be different.Following
- Uchechukwu Awada added an answer:What are the current simulators for energy efficiency in Cloud data centers?The simulators are currently been used for energy efficiency in cloud computing research.
@Muhammad...Thanks for your contribution.Following
- Does Einstein's General Relativity need to be adjusted for the Higgs field?
If the Higgs field is responsible for imbuing particles with mass, and mass is responsible for gravity and General relativity also is a theory related to gravity.
"I'll be curious to hear reactions and corrections to this from someone with better Higgs data."
Apparently Robert your curiosity was mistaken as an inquiry which typically involves questioning. Thanks for your clarification.Following
- 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.
It depends on what you mean by infers/interprets. What is your definition here?Following
- Are art and music branches of mathematics?
The use of the Golden Ratio in works of art is now known as the technique of dynamic symmetry. As an illustration, the painter Georges Seurat in his painting La Parade from 1888, carefully planted numerous of the Golden Ratio through the positions of the people and the delineation of the colors.
The Golden Rectangle appears often in different art forms, including painting and musical works. As an illustration, consider the work of French composer Claude Debussy. In his 1894 work "Prelude to the Afternoon of a Faun" he deliberately placed numerous ratios of musical pulses (called quaver units) that approximated the Golden Ratio.
I still think that art is pure human emotion-even when appears as something with the beauty of geometry and optics or random (fractals) .Certainly far from rigid mathematical rationalism .See my surrealistic -roman drawings on face book :https://www.facebook.com/luiz.c.botelhoFollowing
- Does anyone have any suggestion to transport RNA or cDNA samples at room temperature for at least 5 days?
We need to send the samples to another country but we are not able to send them with dry-ice or by lyophilizing. Would it be convenient to precipitate the cDNA? Can somebody explain an easy way to do it?
Hi, you can precipitate the RNA and the pellet you stock in pure formamide and you can ship them. For the cDNA as Yehu mention isopropanol should be OK.Following
- What is your experience/opinion/reference regarding the use of robots in teaching & learning?
+Robots can support education in terms of both teaching & learning.
First, in teaching they can be teacher assistants or even teachers themselves. A key research area in this approach is the creation of robots resembling humans physically, mentally and emotionally. (Educational robots: http://en.wikipedia.org/wiki/Robot#Educational_robot)
Second, in learning they can be objects that are constructed in hardware, or programmed in software. (Educational robotics: http://en.wikipedia.org/wiki/Educational_robotics)
Third, in learning they could also play the role of a student involved in team learning activities or even VLEs/LMSs. (Proposal)
Please share with us a) your experience, direct or indirect providing any results, or b) opinion, e.g. advantages, disadvantages, comparisons, propositions, predictions, or c) interesting references, with respect to the above three perspectives.
In my opinion, robot still one of audio visual aids (AVA)Following
- Cytochrome c release - WB identification.
Does anybody have some experience in western blot analysis of cytochrome c release? Especially in the context of human cancer cells? Maybe you can recommend some good antibodies? Thanks a lot!
Thanks a lot Lisa Saxena, Dilruba Ahmed and L. Miguel Martins! I will be trying with western blotting at first but I am truly gratefull for other ideas and tips (which can be really important if WB will not work) :)Following
- How to interprete this gel?
Are these bands primer dimers or not?
lanes 1 -> 7: samples
lane 8: negative control
lane 9: generuler 100bp plus (lowest band of ladder = 100bp)
lane 10-> 16: sample = 1 µl from PCR products in lanes 1-> 7 with nested primers
lane 17: negative control (sample = 1 µl from lane 8)
Can anyone help me with the interpretation of this gel?
I am more less familiar with RACE PCR and my opinion is that your PCR conditions has to be optimized or even you have to chose new primers. If you need more info you can write me; Good luck!Following
- What is the relationship between speed and time in designing the systems?
I plan to investigate the system behavior and the factors influencing them, and I have a model with a circuit design system. In this model, we have tried to design a new plan for the proposed system.
Thank you for your cooperation.
It seems none of us really understand your question, as there are several very different ways of interpreting it. Please clarify.Following
- Is there a targeted amplicon sequencing method to assess viral and fungal composition in microbiomes?
In microbiome studies, 16S rRNA is often amplified and sequenced to look at bacterial composition. Is there an equivalent method or gene one can amplify and sequence to assess viral and or fungal composition in the same consortia?Following
- What do you think about unilateral exophthalmia in Rainbow trout?
Recently I observed a new Unilateral exophthalmia in affected rainbow trout fish during infectious mortality in coldwater fish farm in suspected fish.
The rate of mortality was sharp and sudden mortality was occurred.
What do you think about main causative agent in this outbreak?
A unilateral exophthalmia may be caused by strong circulation in a round tank, perhaps a tank with a rough concrete or fiberglass surface. If fish are swiming against the current or swept along with it in one direction a unilateral condition can occur. We have seen this with tilapia and other species as well.Following
- Do we need to strike the balance between the theorists and the practitioners?
We usually talk about correlation between theory and practice and we wish for our best employees to have good base in theory and great practical experience as well. How can it be achieved in current system of education?
The way I see it : I have been trying to bring more theory in my office/everyday business practice and professional life, and my practice/experience into my academic projects and research. But, (there is always "but" somewhere) it seems to me that two worlds are divided more then ever. On the one side, we have the great theorists, and on the another side we have the magicians of practice. It takes serious time and energy to put those two together. How it can be achieved in classrooms? Are there any "short cuts" so this type of individual can be created by professors at Universities, or it is all part of "personal mission"?
What do you think?
Looking forward to hear some thoughts on this one.
Dear Masa and Ljubomir,
I'm wondering if this is a heredity of the old system or a result of swift changes due to adopting different standards and practices. Can you spell more details, please? Is it specific to your country or can we see it in some other places as well? I may know the answer to my second question but prefer straight facts to educated guesses:)Following
- What is the difference between CHAPS and NP-40 added into the protein purification buffer?
For disrupting the hydrophobic interaction when do protein purification, which is more efficient between CHAPS and NP-40? In general, what is the concentration of them in purification buffer? Thank you very much~
I usually use NP-40 in a final concentration of 1%. It works pretty well.Following
- How important are group sizes in randomisation for an RCT?
I have recently reviewed an RCT involving 328 patients randomised into a treatment group with 183 patients and control group with 145 patients. I understand the 328 were randomised as an entirety (no block randomisation). This group size is significantly different from a perfect 50:50 split on significance testing Chi2=4.4 DF=1 , P= 0.0359.
Is this a meaningful difference in group size? How would it effect the study? Or is it simply a feature of true randomisation?
Dear David, stringently, to use group sizes larger then power calculation bears the fraud to 'test' more patients then needed to fix the study. Basically, you have more patients 'at risk', being it in the treatment arm or the placebo one then needed. The patients in the less favourable arm are at 'risk' (money, ineffective treatment, adverse events) needlessly. Yet, the power itself doesn't suffer.
While we have type I error (p) that defines significance, and type II error that defines MINIMAL power, a type III error is not established. As I have an interest in math, I am working on a model defining such an error, let's call it type III, that defines an upper limit in numbers where numbers and effect, even significant efects, becomes useless due to missing clinical relevance. The crucial number to say 'skip the study' will be around n = 1'000 or more, therefore your study won't be affected.
Back to the topic, using sealed envelopes is out-dated. A friend of mine told me confidentially, that they could assume the allocation by holding the envelop against the sun. As their study was conduced during soccer world championship, the true randomisation was soccer: no soccer = treatment, soccer = shame procedure... Yet, if you have group sizes 100-200, what would block-randomisation in packages of 100 change? It would even it out because every package would be 'forced' to be 50:50. Yet if the base-line characteristics are even, as Dr Sardine said, the imbalance is neglect-able in concern of the studies findings, yet in the case under discussion it can be considered 'over-treatment' as fewer patients would have been enough to answer the question.Following
- Is the Thermal Insulation of Buildings Misbelief or Answer of the Problem?
There are more and more contraversial discusssions about the sense of actual intensified legal regulations for thermal insulation. Are there any experts who starts a serious scientific and technical discussion for a reliable view of that topic.
The actual energy economy discusion and the legal regulations fosters the use of insulation material in buildings in an extent which is not yet economical. There are actually only a few architects and civil engineers which recognize this situation by their real life experience and starts first critical discussions and offers technical proofs.
This controversity is known and although their arguments are open documented ..... no reaction at the legal institutions can be recognized up to now.
This should be changed........
Everybody who is in agreement with this facts is welcome here to give his input.
With best regards