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# Classics - Science topic

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Is there a classic textbook on Belief Propagation
At the moment I do not any book or booklet concer Belief Propagation.
For me you question is not clear.... you refers at what?
Should be more easy if you explain quite in good coditions.
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I assume it's true that physics can generate statistical integration that replaces the classic FDM techniques used as the basis for Simpson's, trapezoidal, etc. integration rules.
Additionally, there are one-step physical statistical integration formulas for any arbitrary number of free nodes n = 3, 5, 7 ..etc where, as Simpson's rule is limited to n = 3 and its multiples in the repeated steps.
yes, Classical physics can generate lots of condition for implication of Sympson's rule, Trapezoidal's rule or Weddle's rule.
If we calculate velocity or distance under different circumstances.
Classical theories evolves new theory and the application of various models of statistics and rules are suitable for the validation and adaptation.
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Consider the quantum field theory (QFT) operator (an operator for each space-time point) that the field amplitude becomes when making the transition from classical field quantities to QFT operators. We will call this the field-amplitude operator. The type of field considered is one in which the classical field amplitude evaluated at a given space-time point is a complex number instead of a real number. In the QFT description, the field amplitude is not an observable and the field-amplitude operator is not Hermitian. Can we still say that an eigenstate of this operator has a definite value of field amplitude (equal to the eigenvalue) even when the field amplitude is not an observable and the eigenvalue is not real number?
Thus, we agree that a real field amplitude is an observable, presumably. I think this can be extended to a complex field, which just consists of a couple of real fields, assembled in a complex number to better represent the O(2) symmetry.
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I have a protein that seems to relocate from the cell surface to an intracellular compartment when phosphorylated. When not phosphorylated the same protein appears to be associated to the cell membrane or outermost plasma membrane.
A classical membrane fractionation western blot experiment shows that this protein is always associated with the membrane pellet and not with the cytosolic fraction. The fraction markers are working perfectly.
I think that fusion to the outer membrane results in filopodial extensions that are enriched with my protein.
The attached image shows the distribution of a GFP fusion of my protein in 2 different conditions.
What should I do to try to test or demonstrate my idea that this protein is associated with membrane regions that can endocytose and become intracellular or can fuse with the surface membrane?
There is no transmembrane region.
Hello Neal,
You might find tips looking at the GPCR literature. G protein-coupled receptors are actually doing this in response to prolonged activation, called internalization. The receptors from the plasma membrane get internalized to endocytotic vesicles, later can be fused back to the plasma membrane in the original orientation, which process can be monitored with a labeled antibody against an extracellular epitope. You might get some tips from those experiments.
Besides the UC fractionation, you might track the route of your protein by co-labeling with different endocytotic marker proteins, there's a lot for early and late endosomes as well.
Best, Karoly
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In the elementary quantum mechanics (QM) of a single particle responding to a given environment, the state of the particle can be specified by specifying a set of commuting (i.e., simultaneously knowable) observables. Examples of observables include energy and angular momentum. Although not simultaneously knowable, other examples include the three rectangular spatial coordinates and the three components of linear momentum. Each observable in QM is a real number and is an eigenvalue of some Hermitian operator. Now consider quantum field theory (QFT) which considers a field instead of a particle. First consider the classical (before introducing QFT operators) description of the state of the field at a selected point in time. This is the field amplitude at every spatial location at the selected time point. For at least some kinds of fields, the field amplitude at a given space-time point is a complex number. Now consider the QFT corresponding to the selected classical example of a field. Is the field amplitude an observable even when it is not a real number? It is not an eigenvalue of any Hermitian operator when not real. So if the field amplitude is an observable, there is no Hermitian operator associated with this observable. My guess (and my question is whether this guess is correct) is that the real and imaginary parts of the field amplitude are simultaneously knowable observables, with a Hermitian operator (assigned to each space-time point) for each. This would at least explain how the field amplitude can be an observable but not real and not have any associated Hermitian operator. Is my guess correct?
The same as in quantum mechanics, only now they're probabilities per unit time and unit volume.
The field amplitude isn't observable, any more than the wavefunction is; it's the modulus squared of the field amplitude that describes the probability density at each point in space and time.
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It is a classical philosophical book.
Sorry outside of my field
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I am facing this #error while giving input of river to Visual #MODFLOW Classic. The input is as a #shapefile. The error is '00-1' is not a valid integer. PFA the screenshot of the error for reference. I would be highly obliged if anyone could #help in this regard.
You are most likely trying to import floats for integers. E.g., row, column, and layer numbers have to be integers.
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I often encounter in different research paper the terminology "top-down" approach or "bottom-up" approach for Human Action / Activity Recognition. These two terms are usually used by papers that use classic approaches and classic ML methods. What does each one mean ? And what could be the difference between the two ?
Simplifying things: the terms are used by specialists in encomiastic rhetoric to characterize the ideological message through which ideas of the imperial program are communicated from the imperial court to the provincial environment, the army, etc. (top-down), respectively the adhesion response from the provincial environment, etc. to the imperial court and sovereign (bottom-up)
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Dear colleagues in System Engineering and Automatic Control:
I used to apply classic controller on industrial processes such as PID controllers
Do you have an idea about what are the recent and modern techniques that scientists and researchers are using ?
Hello,
you can try this technique:
Best,
Loïc
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Being inspired and encouraged by the quantum science revolution in the early 1990s up until our present time, lately I've been following the research by Roger Penrose and Stuart Hameroff on consciousness and mind-matter duality where the extent of knowledge gained thus far concerns how neurons and neural networks in the brain give rise to the phenomenon of human consciousness. My research seeks to go further by proposing that it is non-material information external to the body that interacts with neurons in the brain that gives rise to the mind-body duality. So my specific question is this: What is the mechanism or process through which information interacts with neurons and neural networks in the brain so that a quantum moment becomes a classical action or behavior?
“…Being inspired and encouraged by the quantum science revolution in the early 1990s up until our present time, lately I've been following the research by Roger Penrose and Stuart Hameroff on consciousness and mind-matter duality where the extent of knowledge gained thus far concerns how neurons and neural networks in the brain give rise to the phenomenon of human consciousness….”
- really there is no necessity to pay some attention to existent in mainstream science solutions of the problem “consciousness and mind-matter duality”. The “consciousness on Earth” phenomenon, which resides on every living being on Earth, including humans, and governs the beings, is fundamentally non-material phenomenon, and any structure of practically material neurons and neural networks in the brain fundamentally cannot give rise to the phenomenon “consciousness”, including the human’s this consciousness version.
Including so that
“….My research seeks to go further by proposing that it is non-material information external to the body that interacts with neurons in the brain that gives rise to the mind-body duality. So my specific question is this: What is the mechanism or process through which information interacts with neurons and neural networks in the brain so that a quantum moment becomes a classical action or behavior?…..”
- essentially isn’t correct. When a living being’s, let here a human’s, consciousness, obtains information about external, that is/are in everyday practice and mainstream sciences practically always completely material interactions of completely material sources with practically completely material body’s sensors [say, when light that is radiated by a material object interacts with retina molecules in eyes].
Further the practically material electric pulses pass through practically material neurons, and hit in some “well lesser material” structures, in this case in brain and in some structures where some “well lesser material” reflexes are written.
Reflexes respond the pulses “automatically”, the corresponding “well lesser material” structures in brain process the pulses so that the obtained information is processed first of all in non-material modes of the just consciousness operation, up to the highest, and completely non-material – “mind mode of operation”, which in everyday practice and mainstream philosophy and sciences is called “mind”.
So really there is no any “mind-matter duality” – in the mainstream that as a rule is “mind-body” problems” and “solutions”; that exists in the mainstream because of in the mainstream all really fundamental phenomena/notions, first of all in this case “Matter, “Consciousness”, “Space”, “Time”, “Energy”, are fundamentally completely transcendent/uncertain/irrational and so in every case, when mainstream addresses to some really fundamental problem, the result completely obligatorily logically is nothing else than some transcendent illusory mental constructions.
The fundamental phenomena/notions above can be, and are, scientifically defined only in framework of the Shevchenko-Tokarevsky’s “The Information as Absolute” conception
https://www.researchgate.net/publication/260930711_the_Information_as_Absolute, and more concretely in models of Matter and Consciousness; relating to the thread question see first 11 pages, including section “What is Life” in
- more about what is consciousness see first approximation consciousness functional model https://www.researchgate.net/publication/329539892_The_Information_as_Absolute_conception_the_consciousness
Cheers
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Hello,
We just got from a collaboration some culture supernatant from a hybridoma cell line containing a monoclonal antibody that we are supposed to use for immunostaining. I have experience with classical purified commercially available antibodies for stainings, but haven't used conditioned media before. How does the protocol change then? Any tips?
Thank you,
Lluís.
In my experience, I have used cell culture supernatants containing MAbs at low dilutions. I have even worked with supernatants without diluting them.
This depends very much on how much the specific hybridoma produces.
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I see several studies on optimal tax audit that assume the revelation principle (Myerson, 1981) on a tax game. The conventional tax game refers to a taxpayer who has a true income (private information) and reports a taxable income for a tax agency. The taxpayer has incentives to report a taxable income which is lower than the true income, so to pay less taxes. If the tax agency caches the taxpayer in a probable audit, the tax agency observes the true income, requires the payment of the full tax plus a fine over the evaded taxes. In this case, the taxpayer problem is to maximise the expected net income after taxes. The tax agency problem is to design a policy to maximise tax revenues subjected to costly audits, over the full population of taxpayers. Everything fine up to now.
Nonetheless, for the analysis of the tax agency problem, several studies declare that they assume the classical revelation principle by Myerson (1981), so to simplify the analysis. For example, on the study of Border and Sobel (1987) entitled Samurai Accountant: A Theory of Auditing and Plunder, they state (page 526 of the study):
"Without loss of generality we can restrict attention to incentive compatible direct revelation schemes, i.e. those in which the agent truthfully announces his wealth and makes a payment (which for convenience we will call a tax) based on his announcement to the principal and the principal chooses the probability of auditing based on reported wealth."
This whole sentence does not make so much sense for me: if the tax policy is equivalent to a direct revelation scheme that makes the taxpayer report truthfully, true income and reported income are the same (Nash equilibrium), so tax audits would be unnecessary. At the same time, we know that tax audits are necessary, for the taxpayers would have strong incentives to evade if there are no tax audits. In this case, I understand that the tax policy is not equivalent to a direct revelation scheme, so the revelation principle would not be applicable to this case.
So, what am I missing here?
Yea, so I analysed this and reflected for some time. For one thing, it is true that the revelation principle is applicable only to a limited set of phenomena, under strong conditions.
On the other hand, according to the conditions required for the revelation principle to be applied, I found that there EXISTS an audit mechanism which compels all taxpayers to report truthfully. However, this equilibrium is sterile and mostly useless, for this mechanism refers to an audit scheme with an audit probability going towards zero, and a tax fine going towards infinity; this is the only Nash equilibrium I found.
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Besides one of the classical readings on multiple literacies from a Deleuzian perspective (Mansy & Cole, 2009), I am interested to know what else is worth reading in this area.
Thank you, Mariela.
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I am a Chinese scholor majored in metonymy studies in Chinese classics. If you have interest, let's share some points.
@ Ahmed T. Hussein Thank you so much, Professor Hussein. I am so grateful for your inspiring information and papers. What you suggested is helpful for my study and I have followed your studies and hope to learn more from you.
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Genetic engineering should be seen as one of the many tools available for use by plant breeders to improve crop varieties so that we increase food production, control pests, and improve farm profits.
Dear @Sravani Ponnam
Plant breeding, in its broadest sense, is the art and science of changing the plants genetically in relation to their economic use. Whereas, genetic engineering is the genetic manipulation (bypassing sexual reproduction) such that individuals with a new combination of inherited properties are established. Plant breeding is essentially a technology, and it utilizes various techniques. To my opinion, genetic engineering is the well utilised technique of present day plant breeding. Of course, many hold different opinions! The details can be accessed at:
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At the point we have reached in taxonomy and systematics today, it seems that we are in a situation where details and extremes (in the popular sense) ignore the basics (in the classical sense). Therefore, in a popular sense, we seem to be in a situation (especially by amateur researchers) in which many researchers publish articles without adequate knowledge of the scientific foundations, or even if they do, ignoring these foundations. From this point of view, I think that we should remember the scientific foundations again and know what and how the studies serve.
In this sense, what is taxonomy iessentially and clearly? From what need and how did it arise? What is its main subject and approach? And again, what is systematic essentially and clearly? From what need and how did it arise? What is its main subject and approach?
I think these questions should be answered clearly.
Can a systematic study be done without knowing the taxonomy and a taxonomic study without knowing the systematics? Concisely and clearly, what is a taxonomic study and what does it encompass? What and how does it serve? Also concisely and clearly, what is a systematic study and what does it encompass? What and how does it serve?
I would appreciate if you could share your valuable ideas...
Jean-Paul: Taxonomy is one thing, ecology is another, anf conservation is still another - they are important to each other, often (ecology) help in interpretation, but their direct aims are different and so they should not be mixed. A taxonomist need not to be ecologist, to describe and/or classify a taxon ecological or conservationist considerations may (ecological) sometimes help (providing useful suggestions) but often (especially conservationist) lead astray ("make the subspecies X a full species to increase its conservation status"), reducing taxonomy from serious branch of science to a formal game!
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Looking for information on Microscopic Thermodynamics? Check out this repository of information and examples made available free on the Web by Professor Pohl, derived from his classic textbook, Microscopic Thermodynamics, by Irey, Ansari and Pohl, John Wiley and Sons, 1976, ISBN 0-471-42847-7. http://thermospokenhere.altervista.org/
I am managing the site for Jim Pohl during the transition from www.thermospokenhere.com (paid) to thermospokenhere.altervista.org (freebie) so let me know if you find any broken links or things that don't work.
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Will instalment of quantum technology at global scale prove to be eco-friendly? Will it be able to solve all the environmental issues that classical/current technology has created?
4 Ways Quantum Has The Potential To Be a Powerful Problem Solver, Massive Energy Saver For The Environment
There are a lot of reasons to promote quantum computing — from advancing science to addressing the limitations of classical computing — but researchers are increasingly suggesting that the most important mission of quantum computing and other forms of quantum technology will be its use as a tool for scientists and entrepreneurs hoping to halt — and even turn back — climate change.
In a study published on the pre-print server ArXiv, a team of researchers, including leading industry experts and academics, listed four reasons why quantum computing can help scientists solve arguably the most important challenge of our era.
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Hello everyone,
Because of the various differences in the mechanisms of TNT and hydrogen explosion, i've been wondering if JWL parameters existed for hydrogen to replace the classical TNT mass equivalence approach. If not, have there been equations of state developed specifically for the purpose of hydrogen cloud explosions?
ેદીીબ, I do not know
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Canny algorithm is a classical edge detection model. I want to use an automatical thresholds algorithm for Canny to identified the water in Sentinel-1 images.
The poblem now is that i can hardly find a suitable automatical thresholds algorithm. I have test the result with Otus, but not all histograms are bimodal, so i wonder whether Otus is suitable here? And, is there any other model can used on Canny?
The code is best implementable in Google Earth Engine.
The traditional Canny algorithm has poor self-adaptability threshold, and it is more sensitive to noise. In order to overcome these drawbacks, this paper proposed a new edge detection method based on Canny algorithm. Firstly, the media filtering and filtering based on the method of Euclidean distance are adopted to process it; secondly using the Frei-chen algorithm to calculate gradient amplitude; finally, using the Otsu algorithm to calculate partial gradient amplitude operation to get images of thresholds value, then find the average of all thresholds that had been calculated, half of the average is high threshold value, and the half of the high threshold value is low threshold value. Experiment results show that this new method can effectively suppress noise disturbance, keep the edge information, and also improve the edge detection accuracy.
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[This classic Lenski paper][1] computes the effective population size of an evolving *E. coli* population subjected to daily population bottlenecks as \$N_e = N_0 * g\$, where \$N_e\$ is the effective population size, \$N_0\$ is the population size directly after the bottleneck and \$g\$ is the number of generations between bottlenecks.
Unfortunately, the formula was not derived in the referenced paper and the referenced articles appear to not describe the formula directly, but only provide the fundamentals for deriving it.
Can someone explain how this formula comes about?
hi,
“Effective population size” is the size of an idealized population that would have the same effect of random sampling on gene frequency as that in the actual population.The effective population size (Ne) is the number of individuals that an idealised population would need to have in order for some specified quantity of interest to be the same as in the real population.Effective population size (Ne) is one of the most important parameter in population genetics and conservation biology. It translates census sizes of a real population into the size of an idealized population showing the same rate of loss of genetic diversity as the real population under study.
Population size, technically the effective population size, is related to the strength of drift and the likelihood of inbreeding in the population. Small populations tend to lose genetic diversity more quickly than large populations due to stochastic sampling error (i.e., genetic drift).
Best wishes..
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Could you please suggest any articles/book chapters where I could start with to learn the concept of Total Variation in classical signal processing? I would like to relate to Graph Signal Processing in understanding Fourier Basis.
Hi please go through the attached reputable research papers to clarify the concept. It is generally used in image processing and has limited application in signal processing. The above-mentioned definition from Fernando is acquired from the paper from Fikret et al. and can be a good starting point to increase your knowledge on the topic.
Fikret Işık Karahanoglu; İlker Bayram; Dimitri Van De Ville, "A Signal Processing Approach to Generalized 1-D Total Variation", IEEE TRANSACTIONS ON SIGNAL PROCESSING
Condat, L. (2013). A direct algorithm for 1-D total variation denoising. IEEE Signal Processing Letters, 20(11), 1054-1057.
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Dear all,
We have performed a classical trypan blue stainning. We would need to decolore it, but by using no toxic products. Do you know if alternatives to chloro hydrate decoloration are existing?
Thank you very much.
Finally we did not use trypan blue anymore, but we found an alternative to clear roots before stainning (three days incubation with K0H 20%). Hope it can be useful for you. Best regards.
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When a group of motions are possible in many body problems, it is said that the motion that actually occurs is the one with least classical action S.
In looking at the integral of Lagrangian, for calculation of S, it appears that the motion that occurs is the one that flattens space time as much as possible.
One possibility is that space time is in some way elastic in curvature strains, with neutral stress in the case of flat space time, not surprising when considering the special case of gravity.
It doesn't seem to explain why many body problems would always tend to decrease stress energy.
Why Does Classical Action S Trend Toward Flat Space Time?
I did not get that question when I taught advanced electromagnetism to physics undergraduate students, thank God. But since I taught it and at the beginning of the course, gave a summary of special relativity (a fast one), I can tell you the following:
For special relativity in the 4D Minkowski space:
S = - m c2 ∫ √ (1 - v2/c2) dt (1)
if v << c then we can approximate (1) for a 3D classical case as:
S = ∫ (-mc2 + mv2/2) dt (2),
in equation 2 we immediately see the 3D classical space, where the first term is for potential energy, for example, the gravity field g with a 3D U potential, and the second is the K term for classical kinetic energy where for many-particle systems m can be simply replaced by a sum of "Σi mi" classical point particles; and we finally get:
S = - constant (t2-t1) + ∫ K dt (3).
So in a 3D classical flat space, only the kinetic energy for many particles in a classical system is time-dependent but the potential energy is linear in time, i.e. Upot(x,y,z) only.
That answer can be found in the book:
L. Landau & E. Lifshitz. 1971 The Classical. Theory of Fields. Third Revised English Edition. The Course of Theoretical Physics. Volume 2. Pergamon Press
Best Regards, interesting question in a electromagnetism advanced course.
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We know classical prospective cohort study is an analytical study . But can a cohort study be there without any comparison group and what would be the strength of association in this case?
Good afternoon..No cohort with no comparison group
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Software for plotting Geochemical data
There are a few packages available in R, mainly rgr, GcClust. If you are not versed in statistical programming there is a program called Petrograph that I found mentioned in another thread, where it is described as user-friendly and free. You can also do analysis in Excel if you are working with a smaller data set.
Check out this link, it might be of use for you: https://serc.carleton.edu/NAGTWorkshops/petrology/plot_programs.html
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We note that more and more hikers are using Apps, social networks or other technologies to support their hiking activities. Are there differences between technological hikers and classic hikers? What do they use these technologies for? Are they useful?
Studies have shown how various technologies mediate the relationships between individuals and the environment e.g. in the context of hiking/walking/driving in nature - and consequently the experiences of self and other(s). One can expect that social media and various apps new has added more and complex layers to the mix.
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It seems that sustainable agriculture could mean the main goal of future agriculture. Implying increasing in yield, with a lower impact on the environment and also enhancing the social aspect of people. Nevertheless, this idea involves so many metrics and factors that we could easily lose the point and not move forward to this goal. I am sure that many institutions and companies announce that they are working towards sustainable agriculture, but how we can be sure about this? So far any metrics standardized and compared this topic among companies or institutions, seems to work. For instance, I found very interesting the SAFA framework proposed by FAO. However, it seems to be so complex or difficult to follow that as far as I am concerned, this framework has not been widely used as perhaps was expected.
Continues recording and working with classical economics measures appear to be the most common and typical form to assess sustainable agriculture. But could we develop better measures towards this goal?
The best way is to use expensive organic fertilizers with nutrients in order to sustain the productivity of the land and to maintain its productive capacity continuously.
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If we use Qiskit what we get is probalistic data. However if we want to process quantum image processing, the first thing we need to do is quantum image representation in matlab. So what will be the logic behind the representation of quantum image where we take classical image as base.
They suggested a solution in the website:
https://qiskit.org/textbook/ch-applications/image-processing-frqi-neqr.html appears to have Python code that you might be able to use from MATLAB.
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Dear researchers,
I hope you are well and in good health
Concerning fractional derivatives and analysis.
If the notion of classical derivative gives us more information on the variations (Df is positive implies f is increasing), what information is provided by the fractional derivative, for, example D^{1/2}?
That on the one hand, and if you want to do the numerical, what do you think is the approximation D^{1/2}?
All help is appreciated. Best regards
Dear Professor Zoleikha Soori,
I thank you very much for your answer to my question while talking about the applications of fractional derivatives in Physics. What I don't really understand is that there is a problem of conformity between these different definitions, for example, the fractional derivative of a constant is null for one definition and not for others, which generates difficulty in applications, especially for numerists.
Kind regards
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Working GAN which makes use of deep learning (neural networks) to create synthetic data. Does anyone have any idea or material that inculcates the use of classical machine learning algorithms instead of DL? Or is this possible in the first instance?
GANs function by first training a generator network, which produces synthetic data, and then running a discriminator network on the generated data. The gradient of the discriminator network's output with respect to the synthetic data indicates how to gently alter the synthetic data to make it more realistic.
Actually, A generative adversarial network (GAN) is a machine learning (ML) model in which two neural networks engage to improve their prediction accuracy.
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What is the fastest and most accurate way to solve an MINLP model with nonlinear constraints, including triangle and quadratic terms? classic solvers, metaheuristics, or ...?
Any tips are appreciated.
For solving your problem it is requiered to make evolve a solutions population. In each iteration you must to verify the fulfilment of your restriction and to add the corresponding value to the objective functions evaluations. For doing it you could different algorithms. In the works attached you can find a clear explanation about the mains ideas.
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What are some good books (both new or classics) on community ecology and restoration ecology, which can be helpful to build concepts for a PhD? (My specific field of study is ornithology)
Dear Prakhar Rawal,
I used the book of Community Ecology written by Peter J. Morin is referenced below:
Morin, P.J., 2009. Community ecology. John Wiley & Sons, in my doctoral study. I find it as a general holistic book covering all conceptions related to Community Ecology.
Good luck
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Please if anyone has a recipe for determining or developing or constructing a classical force field for a new molecule for which there is no experimental data. These classical force fields are required for the classical modelling of a refrigerant (MEA). That is, using classical force fields to simulate the equilibrium composition of a bulk reacting system. Also, how would one simulate an equilibrium adsorption isotherm when the adsorbent undergoes a chemical reaction with the adsorbate particles?. I am looking at information on classical thermodynamics, particularly as pertains to phase and chemical reaction equilibria. Any information (including suggestions, articles, books or links) on these questions is welcomed.
I am not specialized in that field
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I am trying to do the classical Molecular Dynamics simulation of the crystal structure of ethanethiol (or ethyl mercaptan) C2H5(SH) To do this, I need the experimental crystal structure of the molecule to use as the starting configuration for my simulation.
Dear Shubhadeep Nag this is a very interesting technical question. As an inorganic chemist I personally never worked with ethanethiol (ethyl mercaptan). Surprisingly, I could not find any literature references reporting the X-ray crystal structure of this very simple compound. Even the Cambridge Crystallographic Data Centre (CCDC) showed no entry (provided that I did the search right). Thus chances are that the solid state structure of ethanethiol has not yet been determined by X-ray crystallography. At least I have been unable to find such data... Perhaps nobody wanted to crystallize ethanthiol at low temperatures because of the unbearable stench of the compound. In any case I hope that someone else will be more successful in this literature search.
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Just for some context, I'm isolating non parenchymal cells with Pronase+Collagenase D, which is a well known protocol in my lab. I use DAPI as a viability dye in my FACS panel but I encounter some issues as it also stains high DNA content cells or mitotic cells, representing around 20% of the cells (see picture). No solution in the protocol contains detergent that could permeabilize the cells, and the mouse used is a classic healthy C57 so mitotic cells are not expected, at least to that extent. Did anyone encountered the same issue in the past? Thank you
Reduce the concentration of the DAPI
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I have project to determine the action spectrum for phototherapy of neonatal jaundice. Since 1958 this has been widely assumed to overlap the in-vitro absorption spectrum which has a maximum at 460 nm. There is now convincing evidence for an action spectrum centred on about 480 nm. I want to illustrate my report to CIE with graphs of the "classic" absorption spectrum and the spectrum recommended by authors such as Lamola and Ebbesen.
Although there are plenty of papers showing the in-vitro absorption spectrum centred on about 460 nm, no one seems to give a reference shwing where that came from. I can only refer to it as the "classic" spectrum, as if it has the status of "E=mc2" and everyone knows that came fro Einstein 1905!
Has anyone got an original reference for the often quoted absorption spectrum centred on about 458 nm?
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Was Heisenberg a Third-Rate Natural Philosopher because he denied the reality of micro-objects that cannot be tracked by humans? Has this misled physics for 100+ years?
Surely, because we have created a whole civilization from the manipulations of electrons, especially digital electronics, then "LOOKING" at an object is NOT a requirement for existence.? Electrons interact with everything; so surely quite sufficient, eh?
Heisesenberg was educated in the Classical Philosophy of Aristotelian Classicism in the archaic German Education system. He failed to think for himself, substituting a Platonic idealist view of mathematics, as being superior to our imaginative/operational view of reality.
Pity; just be careful near high edges.
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Hello,
I wanted to ask if someone can summarize which physical processes can and can not be explained by classical and quantum light material interactio formalism?
I know that single photon experiments need full quantum description, also spontaneous emission is same, needs quantization of light to explain,
I know that Absorption can be explained full classically (electrons as harmonic oscillators and light as EM field that drives it),
So can someone summarize most well known (even less known if possible),
It is interesting to know how successful semiclassical approach is ( I heard that it explains nearly all processes)
thanks
This is a very interesting question and it highlights the fact that we don't have a fully unified description of physical phenomena. I have been working on a fully unified approach called the spacetime wave theory:
In this approach there is no distinction between classical and quantum. In this approach light is quantised because that is the way it is emitted. Quantisation is not an inherent property of light, just a result of the fact that atomic bound electrons can only occupy discrete energy states. The reason for the quantisation of electrons is due to the nature of the electron as a looped wave in spacetime which encircles the nucleus many times and adopts energy states which have a local minimum. The cause of the property electric charge is explained by the Spacetime Wave Theory.
With this approach you can take a phenomenon such as the photoelectric effect and treat the incoming photon as a wave quantum with a certain energy which may or may not be sufficient to be absorbed by the orbital electron (which is a looped wave in spacetime) to move it to a higher energy state which removes it from the atom.
So by adopting a new physical description, we get rid of the false distinction between quantum and classical.
Richard
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A Fresnel imager is a proposed ultra-lightweight design for a space telescope that uses a Fresnel array as primary optics instead of a typical lens. It focuses light with a thin opaque foil sheet punched with specially shaped holes, thus focusing light on a certain point by using the phenomenon of diffraction. Such patterned sheets, called Fresnel zone plates, have long been used for focusing laser beams, but have so far not been used for astronomy. No optical material is involved in the focusing process as in traditional telescopes. Rather, the light collected by the Fresnel array is concentrated on smaller classical optics (e.g. 1/20 of the array size), to form a final image
As a diffraction based optics, its performance is closely bound within certain wavelength band. If observaton is only done in such a band, then no problem, it would be great option because of its cheap price. However, it is usually not the case in astronomical observation. So ,it is not quite often to see any project planning to use Fresnel lens for imaging optics. There was a plan I think in US to fabricate a 50m diameter fresnel lens somewhere maybe in early 2000, but the plan didn't go long.
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I am planning to conduct a study that examines the behaviors of people who "defect" or behave non-cooperatively in an online social dilemma game. Thus, I am looking to find a game where a large proportion of players tend to defect or behave non-cooperatively. Does anybody have ideas about which games are the best for this? The classic Prisoners Dilemma Game? The Investment Game? Another?
According to the literature, Prisoners Dilemma games are suited for both cooperative and non-cooperative games. In the particular application to cartels, it is known that defection occurs quickly, except in the application of OPEC cartel. In the application to signal games, where players can send signals to get around competition, cooperation is dominant mostly for non-price over price competition. Usually, the games must be played repeatedly to detect these trends.
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Recently, I got a revision on one of my papers in which the reflection and transmission phenomenon of waves has been studied in a piezoelectric medium with the consideration of a flexoelectric effect.
In the said article I used the classical method for finding the amplitude ratios of the waves.
However, the reviewer suggests that
" It would have been better if the solution methodology was based on Lame displacement potentials where the dilatational and the distortional character of the waves are more easily distinguished."
But as far I know this methodology, the Lame potentials are best suited for the isotropic media.
So,
Is the Lame displacement potential method can be used for transversally isotropic media?
Dr. Sonal Nirwal in addition to the previous interesting answer, in Oil exploration seismic elastic wave propagation, the answer to your question is yes.
The Lame displacement potential method can be used for transversally isotropic media (VTI).
You can try to look at the following open access articles, which I found using Google search:
Best Regards.
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We are working with experimental data in which the dependent variable of interest (is count) has a lot of zeros and some few 1's across the treatments under investigation. we therefore need direction on the best way of analyzing the data aside the classical ANOVA technique.
The original DOE was setup in anticipation of observing some counts for the response variable, however, your question suggests you ended up with dichotomous outcome for the response variable. I propose you redefine the response variable and apply modelling techniques applicable for dv with dichotomous outcomes.
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In classical times there was a concept of pure science that was produced entirely in the intellect.
More recently sciences were developed by testing the intellectual product with empirical data. These sciences are not regarded as being pure.
Mathematics, often regarded as pure science, has for most of history been based on postulates of geometry that could not be proven. Then came relativity and other geometries. In the past century there was considerable effort to reformulate mathematics on a firmer basis of conditional sets. Math is now regarded as being somewhat more pure than before, while producing two generations of graduating students in some countries who are not able to do simple arithmetic.
Fortunately I had some excellent teachers who explained the two systems and why they were both needed. Other teachers displayed the Gödel's incompleteness theorems.
In academic settings there seems to be a difference of opinions about whether or not math is a science, and whether or not it is pure.
Is Mathematics A Science?
Mathematics is a science built on a theoretical basis through the occurrence of a phenomenon or an experiment and taking the data of these phenomena and making them a model, an equation or a system, and then it is solved according to the theoretical foundations.
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In accordance with the classical limit, the probability per attempt of tunneling decreases towards zero as the mass m of a particle, the deficit V − E between its energy E and the barrier height V (E < V), and/or the width W of a barrier becomes large. The probability P per attempt of tunneling of a particle of mass m and energy E through a barrier of height V (E < V) and width W in the classical limit (in the limit of ever-smaller P) is
(1) P = 16[E(V – E)/V2]exp{−[8m(V − E)]1/2W/h-bar}.
In accordance with the classical limit, P approaches zero as m, V − E, and/or W become large.
But, by contrast, there seems to be a paradox if E > V. For the probability per attempt of traversing the barrier is then
(2) P = {1 + V2sin2[2m(E – V)]1/2W/h-bar]/[4E(E – V)]}-1.
The average of sin²x over one or more complete oscillations of any argument x is 1/2, so if E > V a typical value of the smoothed-out probability per attempt corresponding to a given E is
(3) P = {1 + V2/[8E(E − V)]}-1.
Letting E = NV (N > 1), Eq. (3) can be rewritten as
(4) P = [1 + (8N2 − 8N)-1]-1.
Inverting and solving Eq. (4) for N in terms of P (with the help of the quadratic formula),
(5) N = {1 + {1 + [2(P-1 − 1)]-1/2}1/2}/2.
Corresponding to P = 1/2, N = 1.15. Corresponding to P = 0.99, N = 1.92. This is reasonable for an electron traversing a barrier of atomic dimensions. But this is not reasonable for a baseball thrown over a fence of width W = 1 cm and height H = 10 meters in Earth's gravitational field g, which has P = 1 of clearing the fence if its energy E even marginally exceeds V = mgH, not merely P = 1/2 if E = 1.15 mgH and not merely P = 0.99 if E = 1.92 mgH. But if E > V the formulas (2) through (5) take no account of a classical limit: they are identical for an electron and a baseball. [Although g acts vertically, E and V for the baseball can still be construed as one-dimensional, as functions of its horizontal position directly below its path. The same lack of taking into account of a classical limit by the formulas (2) through (5) obtains for any system, however macroscopic.]
Perhaps this paradox is resolved because a PERFECTLY square potential barrier is physically UNrealistic. At the edges of any REAL, PHYSICAL, barrier, the potential increases from zero to V over a FINITE distance greater than zero. If this is taken into account, the probability that a baseball thrown over a fence with E > V = mgH being reflected, i.e., not traversing the fence, is reduced to zero. See Quantum Theory by David Bohm, Sections 3.9, 11.3, 11.4, and 12.1−12.4.
Hi.,
Best wishes..
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Dear Researcher
I want to use the Bayesian estimation method for more than two continuous dependent variables. I prefer to use the Bayesian estimation approach than the classical approach. Is the anyone who can help me?
Teshita Uke Chikako , from your question I assume that you want to model the relationship between these 3 variables jointly? If that is the case, it sound like you want to estimate a Bayesian Vector Autoregression (VARs). If that is the case, there are A LOT of easy-to-use available options to estimate Bayesian VARs. See for example:
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I am by no means an expert on this subject, but a few papers on this subject sparked an interest into whether instantons give rise to a non-zero vacuum expectation value or could be involved in the generation of the Higgs field.
Instantons in mathematical physics arise as solutions to a set of non-linear differential equations than minimize the Yang-Mills functional for a non-abelian gauge theory. This is part of the differential geometric way of writing classical fields in terms of a connection and the curvature of a connection. The classical electromagnetic field is a U(1) connection and the curvature form of this connection is an anti-symmetric matrix that whose entries are the electric and magnetic fields. For non-abelian groups such as SU(2) and SU(3), the connection and curvature of the connection formalism give rise to the weak force of the Z and W-, W+, and the 8 gluons of the SU(3) strong force. The instanton number can be thought of as describing the number of instantons present and is an expression of how "twisted" or topologically non-trivial the vector bundle or underlying space is.
The Higgs field is what gives spin 1/2 particles mass as well as giving mass to the Z and W-, W+ particles. The masses of spin 1/2 particles are determined by something called the Yukawa coupling. My question is how can instantons contribute to a non-zero vacuum expectation value and are there theories that say the Higgs field is built up in this way?
The short answer is No, instantons don’t do this in the Standard Model. The reason is that, in four spacetime dimensions, there is a phase transition between a phase where the expectation value of the Higgs field vanishes and a phase where it doesn’t.
Incidentally, instantons are not, just, classical solutions of the esuatiins of motion of the gauge fields, that connect different vacua of gauge fields, there can exist instantons that connect different vacua of scalar fields.The existence of distinct phases for the scalar field, in the presence if the gauge fields, too, implies that such field configurations, that could affect the expectation value of the scalar, don’t exist.
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Our answer is a consistent YES. A qubit (or quantum bit) is today the quantum mechanical analogue of a classical bit. In classical computing the information is supposed to be encoded in bits, where each bit can have the value zero or one. In quantum computing the information is, then, also encoded in qubits.
This is inconsistent in (1), in a most basic point, because even classically, information is no longer understood to be encoded in bits. Years ago, this was true 50 years ago, but failed.
Today, one uses SystemVerilog with tri-state chips, as opposed to Shannon's theory with binary states, and two-state chips as relays.
Information is encoded in three logical states, in 0, 1,and Z, where Z is an open circuit standing for indeterminacy, with a coherent semantics for interconnects.
The qubit view is inconsistent in (2), another basic way, because one needs to move from the macroscopic, from a classical Boolean analogy of relays or switches, valid for the Law of the Excluded Middle (LEM). Then, in a formless and classical “fluid” model for particles, information was seen in the double-slit experiment as GF(2^m), and now must change to a more complex microscopic structure, with a quantum tri-state+, not qubit in two-state. The photon (e.g., a particle) is now modeled by an algebraic approach with ternary object symmetry, modeled by GF(3^n).
Comparatively, the current two-state quantum theory of qubits is linked, however, to the classical two-state “bit”, following Boolean or classical logic laws, such as the LEM, which carry only two possible values, “0” and “1”. This emulates the workings of a relay circuit, and uses the formless “fluid” analogy of classical information, that can only be blocked (relay open), routed or replicated (relay closed). However, information can also be encoded, in analogy to network encoding as announced in 2000, and not covered by Shannon's theory.
Max Planck solved the ultraviolet catastrophy by his study of black body radiation where he found the energy of oscillating system is quantized, not continuous as the classical physics thought before 1900.
So, radiation is made of quanta with energy depending on the frequency f i.e E = hf, where h is proportionality constant. Einstein, in 1917, proved it by reproducing the law of radiation found in 1900 by Max Planck. That required a coherent channel to exist, invalidating qubits before their concept started. It was a mistake by Shannon that led to bits and qubits.
The mistake was first that Information could be treated as a fluid, which can only be blocked or let pass, as a relay. That led Shannon to consider Boolean logic for Information, the second mistake. Which led to qubits, the third mistake in treating Information. One must use tri-state+ to represent Information, classically or quantically.
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I would like to model the results of a symptom severity questionnaire of a certain disorder using GLM. However, I have a big problem with what distribution to adopt for the questionnaire results. The tool consists of 47 questions using a 1-5 scale, so the score is always positive, takes only discrete values, and has a finite range of values it can take (47 - 47*5). The empirical distribution is additionally strongly right-skewed. Is there a "classical" probability distribution that I can use to model such a variable?
You are really asking the.wrong question.i believe. I would suggest since your questions seem to be LIKERT and thus ORDINAL ordinal logistic regression is probably what you need to use. If any of them yield your DV it's certainly ordinal regression and I attached notes. Google ordinal logistic regression with your stats package name to get examples and videos to watch. Best wishes, David Booth
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Dear Scientific Community:
I am looking for an effective alternative readout of glycolysis inhibition in cancer cells.
In addition to monitor the production of Lactate or Glucose uptake (that are the classic experiments), do you know if there are some genes that is down--regulated or up-regulated after glycolysis inhibition ? (for example, some gene of OXPHOS)
thank you for the help
Marco
You can refer to the research article given below.
Highlight:
Unique sensitivity of tumor cells to the inhibition of glycolysis is a good target for anticancer therapy. Here, we demonstrate that the pharmacologically activated tumor suppressor p53 mediates the inhibition of glycolytic enzymes in cancer cells in vitro and in vivo. We showed that p53 binds to the promoters of metabolic genes and represses their expression, including glucose transporters SLC2A12 (GLUT12) and SLC2A1 (GLUT1). Furthermore, p53-mediated repression of transcription factors c-Myc and HIF1alpha, key drivers of ATP-generating pathways in tumors, contributed to ATP production block. Inhibition of c-Myc by p53 mediated the ablation of several glycolytic genes in normoxia, whereas in hypoxia downregulation of HIF1alpha contributed to this effect. We identified Sp1 as a transcription cofactor cooperating with p53 in the ablation of metabolic genes. Using different approaches, we demonstrated that glycolysis block contributes to the robust induction of apoptosis by p53 in cancer cells. Taken together, our data suggest that tumor-specific reinstatement of p53 function targets the “Achilles heel” of cancer cells (i.e. their dependence on glycolysis), which could contribute to the tumor-selective killing of cancer cells by pharmacologically activated p53.
Best,
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Beginning with Keynes General theory , Phillips curve interpretation of policy trade-off to New Classical and to New Keynesian school of thought, the subject Macroeconomics travel a long path. From adhoc macroeconomics model to representative household in general equilibrium framework , methodologically the subject evolved tremendously. It will be great to find books or articles which capture the journey from the perspective of thought.
"Free to Choose" (Friedman) should be in you history. It explains why the Keynesian doctrine had to be re-done, and re-done From Phillips doctrine failure (requiring one re-done) and the collapse of the Communism (requiring another re-done). And points to why anther re-do will be required.
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What makes scientific article a classical?
First, and more commonly used is number of citations.
Second definition of a classic scientific article is inherent to article itself. These articles are so completely innovatives and disruptive that new protocols have been implemented and new and results have been achieved.
I would appreciate so much if you could answer a fast online questionaire about historical articles:
Best regards
Thank you for help me Dr Salme
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The integral development of children is intimately with the game. In a bibliographic review of this area of scientific knowledge (children's game): Which authors should not be omitted?
"What classical authors should not be omitted from in-depth studies on children's play?" -- Reinaldo Requeiro asks.
Briefly, I would point to classical authors: the Swiss psychologist Jean Piaget and the Soviet psychologist Lev Vygotsky.
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Let ABC be a triangle with angle BAC<90o . Let M on AC and N on AB be two points so that MA=MC and CN is orthogonal to AB. Let P be the intersection point of BM and CN. We suppose that BM=CN. Prove that BP=2PN.
Dear Dinu,
it seems that the assumptions concerning the angles are redundant.
Solution to the problem:
Consider B´such that B is a midpoint of AB´. We obtain two pairs of similar triangles:
1. In the triangle AB´C we have B´C=2BM (=2BN).
2. In NB´C, the ratios BP : B´C = NP : NC.
Putting 1. and 2. together we obtain BP=2PN.
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I am reading the paper of Jeremy Avigad, Edward Dean and John Mumma, entitled "A formal system for Euclid's Elements".
Could this approach be extended to the books of Apollonius of Perga dealing with conics ?
I am interested in complexity questions and the completeness/incompleteness of axiomatic systems for Greek geometry.
Maybe there is more to the late ideas of Frege about basing Arithmetic on Geometry than is generally believed...
Also, inspired by the well-known correspondence between the elementary theory of field extensions and the classical constructions with ruler and compass, one can ask: what kind of field extensions correspond to constructions in which we can draw conics as well as circles and lines ?
You may focus on the relationship between Euclidean Geometry vs Riemannian Geometry or Hilbert or Banach Spaces. See e.g., https://arxiv.org/pdf/1807.11290.pdf
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Quantum Computers have an advantage over classical computers as they are based on quantum states which can be three 0, 1 or superposition of 0and 1. Till now classical had 0 or 1 states of transistors, but if a third state of infinit current is introduced, will it improve them? If we keep aside the engineering difficulty to realize it, in principle, will it reach quantum computer-like computational levels?
A ternary computer which you described has actually been built before. There is an interesting wikipedia article available about it: https://en.wikipedia.org/wiki/Ternary_computer
However, such a classical computer does still lack some of the ressources that a quantum computer provides, such as entanglement or true randomness.
However, it has not been formally proven yet that a quantum computer is more powerful than a classical one (whether binary or ternary), even though it seems very likely.
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Dear Colleagues,
The classical form of speed distribution of particles
Ac²exp( -bc²)dc is valid for particles in 1D box or not. ?
Thanks
N Das
Dear Souvik Bhattacharjee,
I am thinking of free particles in a 1D box.
Say , n number of particles ( identical and distinguishable) particles inside a 1 D box.
Then , dn(c) = A c²exp( -bc²)dc , this distribution is valid or not ?
I can't find the logic of the factor "c²".
Thanks
N Das
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The main result of decoherence theory is that the non-diagonal elements of a quantum object's density matrix become zero due to uncontrolled interactions with the environment. For me, that only means that there will we no more interference effects between the superposed states. But there still remain the diagonal elements of the density matrix. So there is still a superposition of classical alternatives left. How does that solve the measurement problem ?
Moreover, doesn't the mathematical derivation of the decoherence effect involve an ensemble average over all possible environmental disturbances ? How does this help when we are interested in the behavior of a specific system in a specific environment ?
Thanks to 'Juan Weisz' and 'L. I. Plimak' for your quick answers!
I just want to add that the reason for my question was an article ( https://arxiv.org/pdf/1612.00676.pdf ), in which physicists were surveyed about their attitudes concerning the foundations of quantum mechanics. I was shocked to see (in Fig.6) that 29% considered the measurement problem as solved by decoherence, and 17% considered it even as a pseudoproblem. I my opinion, the measurement problem is absolutely important, but still unsolved.
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Heterogeneity in meta-analysis refers to the variation in study outcomes between studies. I-square statistic describes the percentage of variation across studies while is calculated as the weighted sum of squared differences between individual study effects. Which is a classical measure of heterogeneity for meta-analysis (Cochran’s Q or Higgins I-Square)? and WHY?
Chochrane'Q or Chi-square statistic is not reliable in case of few satudies.
I-statistic seems better option in such cases.
It is easy to interpret also.
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If you were to analyse metabolic pathways in T cells (murine and human), how would you prepare the culture medium? And, apart from classical activation, would you add IL-2 for a 3-5 day cell culture?
We use RPMI1640 (supplemented with 10% FBS and antibiotics) for our lymphocyte culture. Now we purchase ready made media from Gibco but earlier we used to purchase powered media and dissolve it in autoclaved distilled water followed by filtration. this is our incomplete media. Now, we used to complete this media by supplementing it with FBS and antibiotics before use.
we are culturing Lymphocytes and T cells upto 72 hours, but we do not use IL2 in culture. but it is recommended to add IL2 in culture for better health after 24 hours.
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In classical biotechnology, three stages are distinguished: pre-fermentation, fermentation, post-fermentation. Typical equipment used in biotechnological industries is known. Are there any features in the hardware design of biopolymer production, such as proteins (enzymes), polysaccharides (starch, cellulose), lipids (lipids of microalgae)?
For thickening polysaccharides, like xanthan, mixing to ensure gas exchange is the limiting factor. At late stages, the injected air tends to rise in huge bubbles with very little exchange.
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Along my research I have focused to a large extend on corporate culture, organizational values leadership and management. I looked at the connection of these soft facts to financial performance and success measurements. I realized that the field of research is less explored then others in this area and that many researchers mainly borrow approaches from classical cultural research on nations. That approach is from my perspective a bit thin and too easy hence it might not capture an organizations unique approach. I invite all to look at my wok and share their work in the field to start a discussion on in which direction research will go. Because we know that just continue as we did so far will bring us not further.
You can assess your current culture in several ways. This culture assessment can involve walking around, conducting interviews , or using a culture assessment instrument.
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is there any book that can explain what kind of classical assumption or diagnostic check that need to be tested on panel data model ?
Econometric analysis of cross section and panel data by Jeffrey Wooldridge is a comprehensive reading on this topic (or even the most established textbook in this field).
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I am facing difficulty to find the gynoecium properly of Mimosa pudia L. which has capitulum or head inflorescence. I have found the androecium after many try. But pistill was too hard, How to be efficient in classical taxonomy study (Morphology based)? How did they described it in literature? I wonder!!!!
I like to use syringe needles you can purchase from a pharmacy as a very precise "knife" or "scalpel". I have dissected many flowers (about 1-5 mm in diameter) of Stelis (Orchidaceae) with this under a common binocular microscopes with magnifications ranging from 8x to 24x. However, sometimes it is hard to fix the flower so it can be cut. In these cases very fine forceps are helpful. Those can be purchased from goldsmiths or clockmakers. If this is still too large, the flower may be fixed on an adhesive tape or sometimes a wet paper is enough.
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Hi,
I am currently working on a project that requires identifying the two subpopulations in mice using flow cytometry and I am having difficulties in my gating strategy.
I am staining with CD45, CD11b, Ly6G, CD11c, F4/80, Ly6C, CCR2, and CD43. Can someone please help me device a gating strategy to identify both classical and non-classical monocytes? Thank you.
The most classical way to stain would be to add CD115/MCSFR to your panel (requires constant EDTA and cold temperatures to prevent cleavage). CD115+ CD11b+ cells would be monocytes and Ly6C could be used to distinguish classical and nonclassical. For your current markers, while nonclassical monocytes have expression of CCR2-RFP in reporter mice (though less than classical monocytes), I haven't used the anti-CCR2 antibody and am not sure how reliable it is. When an antibody isn't staining well and a reporter mouse exists, it may be that the antibodies aren't great. F4/80 won't identify blood monocytes. CD43 apparently is on nonclassical monocytes (PMID: 25373902, used after CD115 staining. I believe any flow cytometry Misharin publishes), but I don't think it is specific. I would be concerned that any gating strategy you devise for nonclassical monocytes using the current markers would capture other myeloid cells (non-neutrophil granulocytes). You could compare the side scatter profile of your classical monocyte gate, nonclassical monocyte gate, and Ly6G+ neutrophil gate. If the granularity of the "nonclassical monocytes" looks like neutrophils, that would be a clear sign the gating is not working. CX3CR1 is another marker of nonclassical monocytes in the blood, but I've always used reporter mice. I don't think the antibody is always reliable. I would recommend adding CD115 if possible.
Something else to consider is that in settings of inflammation and/or emergency hematopoiesis is that neutrophil progenitors (which are Ly6C+) can express less Ly6G. Without CD115 staining, these could be misidentified as nonclassical monocytes
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Close binary stars have been reported to produce red nova at times while they are merging.
Some classical observers reported Sirius as a red star, others reported a white star. Now it is definitely white. Popular explanations try to discount the red claims, not entirely satisfactorily.
Sirius B is reported to be one of the largest known white dwarfs. The possibility for a merger of close binaries in historical times might be considered. Then the claims of red colors could have a scientific basis. It leaves the problem of what a binary pair might have been like while in the main sequence.
Was Sirius B a Binary Pair Of White Dwarfs In Classical Times?
White dwarfs are comprised of electron degenerate matter, and one distinct characteristic of such matter is that the mass of the star varies inversely as the cube-root of its radius, so a more massive star would be smaller, not larger. Good samples of radii and masses of white dwarfs find this relation is a good fit to the theoretical prediction. There is also no evidence for a nebula that might have been produced by either the past evolution of Sirius B, or by any sort of merger. This is attributed to a long time scale for the nebula to disperse, implying short historical-time evolution unlikely.
One reasonable explanation for reported color differences is atmospheric given the star's horizon location from the Northern Hemisphere (see D.C.B. Whittet, 1999, Monthly Notices of the Royal Astronomical Society, vol. 310, Issue 2, p 355).
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Dear all,
I have a naive question. When we want to study Type 1 response, we infect mice with influenza for instance, if we want to study Type 2 response we use for instance T. Bruecei. Does anybody know which type of response we induce when we immunize with our classical protocols such as SRBC or NPCGG/NPOVA/NPKLH?
Thank you very much
From an old hand at immunology, a Type 1 response is what we used to call a T-dependent antibody response, and that is triggered by viruses, SRBC and hapten-carrier conjugate. Basically, the B lymphocyte binds the relevant antigen [in your case, NP], endocytoses it and processes the carrier protein for display on its' surface class II MHC molecules. If a T helper cell recognizes the carrier protein antigen that is displayed, it binds to the B lymphocyte and stimulates it to produce antibody. For naive B lymphocytes, you get IgM initially, but IgG later in the response. Classic immunology.
Type 2 responses are T-independent; the carrier is LPS, or Ficoll or T bruecei. These are or have repetitive structures that bind to the B lymphocyte and crosslink the surface immunoglobulin [IIRC, you need a complex of at least 10 hapens to trigger the response and Toll-like receptors are involved]. For T-independent responses, you get primarily IgM, and some IgG3 in mice.
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I am trying to simulate permeation of gases in polymers. For this reson normally i use the clasic models like dual sorption model but newly i foun dthe non equilibrium lattice fluid model. It seems very promising but it's not easy to understand and use. So i want to know more about advantages of this model in comapre to classic models. Any idea about that? thnaks in advance
Dear Pouyan Golestaneh, the NELF model treats both solubility and permeability isothermes, may be its best advantage is found when studying glassy polymers. Please check these documents. My Regards
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I am currently into liquid crystals and have no related background. Can someone tell me which book is the most instructive one to learn basics of liquid crystals? I am more interested in different phases/textures of liquid crystals.
• The Physics Of Liquid Crystals by P. G. de Gennes and J. Prost. Clarendon Press, 1993.
• Theory of elasticity by L. Landau L. Pitaevskii A. Kosevich and E. Lifshitz, third edition, Butterworth-Heinemann, 2012.
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What is the approach ratio
Virtual Conferences have some interesting features:
-you sit at your desk and have your own "space" and resource within reach
-you can see the details of what presenters explain very clearly, and undisturbed
-you can take the time to formulate precise questions in written form, using the chat of the virtual conferencing system
-the presenter can answer verbally, with slides, and with links to articles shared in the chat
Face to face conferences have very unique features:
-you sit with other people
-if you don't get something, your neighbour will give you a hint
-you can speak to many people about the issues discussed, and get very different views, and valuable opinions and input
-this will stimulate your thought process as a researcher or as a scientist/engineer
-in turn you mind will set itself free, and find new things, beyond your initial knowledge, the knowledge of the presentations at the conference: ideas unformalised yet scientifically will open new paths for you
-you make friends, and maybe you can work with these people in the future: research, article, project, who knows?
-humans are social animals, hence interaction is enjoyable and valuable!
Make the best of what you have: virtual or face to face.
Does it help?
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