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  • Sebastián Dupraz added an answer in Cytokine Receptors:
    Which is the best receptor-mediated endocytosis inhibitor?

    I am studying the scavenging of a cytokine by its receptor, which I presume being internalized by clathrin-coated pits. I want to use the inhibitor to prove that the detected scavenging is due to the presence of my receptor and not to an aspecific internalization.

    Sebastián Dupraz · Deutsches Zentrum für Neurodegenerative Erkrankungen

    Hi Chiara,

    You can also try specific blocking antibodies to inhibit receptor function or receptor-cytokine interaction. If receptor  itself or its interaction with the cytokine are blocked and scavenging continues it may be using an alternative mechanism.

    Good luck!

  • Sajjad Pourasghary asked a question in Oral Cancer:
    What is your idea about chemoprevention of oral cancer by green tea ?

    Chemoprevention,

    Cancer

  • Soufiene Assidi added an answer in Tax:
    Is there anyone interested in the impact of Big-Data on anti-/ tax avoidance?

    Australian Tax Office now is able to prefill over 6 million pages of individual tax return form. In terms of company income tax, U.S. government, alongside with big data mining companies, is monitoring financial activities in worldwide scale to tackle problems such as money laundering and price transferring.

    The abilities of obtaining and processing information would become another decisive factor (other than economic levels or tax rates) that widens or narrows the inequality of revenue tax shares between countries.

    Soufiene Assidi · University of Carthage

    Dear Professor Alex, 

    i don't understand your question but i think you speak about the transfer pricing between big company and their impact in income tax  

  • Mohammad hassan Kheirandish added an answer in Plasmids:
    Does a plasmid influence the Osmolarity of intracellular solution?

    Will addition of plasmid can modify the osmolarity of an intracellular solution for in vivo? Eg: Osm of intra (1x) is 290mm. will it increase, decrease or null the osm of the final solution?

    Thanks in advance

    Arjun

    Mohammad hassan Kheirandish · Shahid Sadoughi University of Medical Sciences and Health Services

     usual plasmids are  nanometric particles so they can not change the Osmolarity but they may borne genes that can change physiological conditions of cell like osmolarity after expression 

  • Navonil De Sarkar asked a question in C:
    Is there a tool?

    Is there a tool that can help me to identify chromosome and coordinate of

    mutations formatted like

    CD300C|CCDS11701.1|r.603g>u|c.242G>T|p.R81L|missense
    POLR2B|CCDS3511.1|r.2509a>c|c.2096A>C|p.H699P|missense
    SLC12A5|CCDS46610.1|r.1990g>u|c.1914G>T|p.W638C|missense
    ZNF334|CCDS33480.1|r.3008c>a|c.1950C>A|p.H650Q|missense

  • Marcos Vinicius Santana added an answer in AutoDock Vina:
    How can I choose the best analysis for after ligand docking?

    My question is not how to choose the best binding pose per se, but do I need to based on any criteria? 

    For example, If I find that the best pose for my most active ligand is the pose with minimal binding energy. What should I do to analyze my other ligands? Look only for the pose with the minimal binding energy?

    I'm asking this because I screened a library of 20 molecules with known activity. For the most active I selected the pose with the minimal binding energy to analyze. But my second best molecule (I already know it is active experimentally) only showed a promising complex after 15 binding poses (I calculated 20 poses for each ligand). 

    In case this helps, I used autodock vina.

    Marcos Vinicius Santana · Universidade Federal Fluminense

    Miguel,

    I'm considering the binding mode and interactions with the enzyme. It's similar to those observed with other active molecules. The fact is, it's one of my last poses.

    I guess it's worth trying to increase the number of conformations as you mentioned, but Vina doesnt seem to increase to more than 20 conformations (I'm checking it right now).

    Your answer clarified some things to me. I'll take a look at that paper

    Thank you!

  • Amin Rezaei Akbarieh added an answer in Dark Matter:
    Why axion is a "cold" dark matter candidate?

    Even though axion mass is very small (~10-6 eV), it is considered as a cold dark matter. I am seeking the possible reason for that.

    Amin Rezaei Akbarieh · University of Tabriz

    If I want to address to this question in a short way, I should say that : 

    The very low velocity dispersion of cold axions, and their extremely weak
    couplings, imply that these particles behave as cold collisionless dark matter
    (CDM).

  • Daniel Martinez Krahmer asked a question in Titanium Alloys:
    What are the precautions to consider when titanium and its alloys are forging in closed dies?

    I need information about type of press (hydraulic, mechanic), preheating dies, forging temperatures, forging atmosfere, lubricants, and so on?

  • Michael Medvinsky added an answer in Mesh Generation:
    What is the best mesh generation practice in finite element analysis mesh generation for problems involving infinite domains?

    In modeling a time-dependent problem in an infinite domain such that EFFECT grows in extent with time, what is the best mesh generation practice. High resolution all the way increases runtime dramatically. Low Resolution all the way yields inaccurate results. Thoughts?

    Michael Medvinsky · University of Utah

    I'm not an expert in finite elements, but from my experience with infinite domain problems I would say the following.

    1) To be precise, numerically you can solve only a finite domain problem.

    2) In order to solve an infinite domain problem you truncate the domain and introduce absorbing boundary condition (to terminate the grid), e.g. BGT, PML etc. Thus, the mesh generation in general is the same as you use for a finite domain.

    3) The resolution in such problems could be limited by the boundary condition.

  • Paul Joseph Croft added an answer in Science Education:
    When one talks about transformative science education, what does it mean?

    I am interested in exploring possibilities of transformative science education for 14-16 year old children from lower economic class. But there is a dilemma. While most children from a slum in Mumbai (India) want to flow with the wind, aspire to become part of dominant ideologies, won't it be unfair to expect some collective action from them to change society and compromise with their aspirations? What is wrong if the children who have not seen the other side of the story, want to experience that and are not motivated in bringing out change in the dehumanizing conditions the community lives in? For example, children who live close to a landfill. What if they just want to leave the place and settle down somewhere else with facilities like proper sanitation, uncontaminated water, unpolluted air, low-violence environment and so on.

    Paul Joseph Croft · Kean University

    Good set of comments so here is another thought: inquiry-based investigations that involve science in the context of human rights and with regard to socio-economic issues.

    Although the items you mention in the original question are inter-related, it can be of value to pick three key foci that naturally flow towards and interact with one another. In that manner the students begin to see connections for themselves, cause-and-effect, and possibly why they could or would or should invest in making a change in something other than their location.

    The three key issues/topics must be very basic (filled with ambiguity once they begin) and seemingly unrelated or perhaps appearing to be irrelevant to their own lives.

    Just some ideas to consider...

  • Shannon L. Cass-Calay added an answer in Overfishing:
    In practice, how are depleted stocks managed after they fail to meet a rebuilding plan?

    We recently completed an assessment of an overfished U.S. stock under a rebuilding plan. The rebuilding plan is intended to achieve the spawning potential at 30% of the unfished potential (i.e. SPR30%) in 2017. Our (2015) analysis suggested that the stock could not rebuild to that target, even at fishing mortality = 0. Management council staff argued that under this condition, U.S. National Standard Guidelines (NS1) allow an annual catch limit (ACL) computed using an equilibrium projection at 75% of FSPR30 (the proxy for F at optimal yield). This would delay the rebuilding of the stock for about 60 years, and permit fishing mortality levels that have recently resulted in ongoing depletion. Does anyone else have examples like this? How do other regulatory councils manage under this scenario?

    Shannon L. Cass-Calay · NOAA Fisheries - Southeast Fisheries Science Center

    Good plan. We are doing something like that, just waiting for some input from our management council.

  • Fiorella Grandi added an answer in Epigenetics:
    Any suggestions regarding the Epigenetics study human Spermatozoa?

    To choose the best technique for the studyEpigenetics of Human ejaculated spermatozoa???

    Fiorella Grandi · Stanford University

    I would check out Molaro 2011 (http://www.sciencedirect.com/science/article/pii/S0092867411009421) which is a fantastic comparative study of sperm methylomes between primate species. Also, work from Cairns group (http://www.sciencedirect.com/science/article/pii/S193459091400143X) has some excellent papers. There are several reference epigenomes for human sperm, so likely that is a good place to start.

  • Marina Papaiakovou asked a question in Trizol:
    Any hints with RNA extraction from nematode larvae (A. viteae) ?

    Hi guys,

    I have been having some issues with extracting RNA from A viteae L3s , the TRIZOL method doesn't seem to work very well, and I have been trying different speeds/times with the TissueLyser and beads from QIAGEN, and freeze/thaw cycles as it seems that cuticles are very hard to break. I recently tried the RNeasy fibrous kit as well, with less beating, but the RNA quantity is so low <10 ng/uL (nanospec read).

    I always try to extract them (A. viteae L3s) along with some controls (like B. malayi L3 or B. pahangi), every time I change something in the protocols. The controls always work..

    They come in 1X PBS and usually the number is about n ~ 500... As cuticles are rich in collagen, I was thinking of applying a treatment maybe with collagenase or if it's full of lipids to precipitate them with acetone ?

    It has been a couple of months since I've been struggling with it so any similar experience/troubleshooting might be really helpful ! Thank you !! 

  • Pamela Carolina Carrillo asked a question in Rietveld Refinement:
    What range of values LX, LW, and GP can have after refinement?

    i am performing a Rietveld refinement for phase quantification of bimetallic catalysts supported on titania/ceria. I obtained a pretty good fit after refining LX, LY but I want to know which kind of values or ranges can be expected to get from them in order to know if it correspond to a reasonable fit. 

    Thanks

  • Vitthalrao Khyade added an answer in Behavioral Physiology:
    What is the physiological or anatomical difference between place cells and grid cells in the hippocampus?

    In the medial temporal lobe,there are specific types of neural cells such as place cells, head-direction cells, grid cells, and boundary vector cells which involved in cognitive map and spatial memory. Hippocampal “place cells” encode the rat’s location within an open environment independently of its orientation and fire in the specific position. The complementary encoding of the orientation, independently of location, is done by “head-direction cells” .I think all of them are pyramidal neurons. So Is there any physiological or anatomical difference between these kinds of cell?

    Vitthalrao Khyade · Shardabai Pawar Mahila College, Shardanagar Tal. Baramati Dist. Pune PIN 413115

     
    Research Group, A.D.T. And Shardabai Pawar Mahila Mahavidyalaya, Shardanagar, Malegaon(Baramati) Dist. Pune – 413115.

    “Dr. APIS” SCIENCE SPECTRUM
    Objective: To Establish the Repository of Contributions of Eminent Scholars and  Information on Science and Culture  For The Society.                                                                   

    -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------                  

         Fenton's reagent

    Fenton's reagent is a solution of hydrogen peroxide and an iron catalyst that is used to oxidize contaminants or waste waters. Fenton's reagent can be used to destroy organic compounds such as trichloroethylene (TCE) and polychloroethylene (PCE). It was developed in the 1890s by Henry John Horstman Fenton as an analytical reagent.[1]

    Iron(II) is oxidized by hydrogen peroxide to iron(III), forming a hydroxyl radical and a hydroxide ion in the process. Iron(III) is then reduced back to iron(II) by another molecule of hydrogen peroxide, forming a hydroperoxyl radical and a proton. The net effect is a disproportionation of hydrogen peroxide to create two different oxygen-radical species, with water (H+ + OH−) as a byproduct.

    (1) Fe2+ + H2O2 → Fe3+ + HO• + OH−

    (2) Fe3+ + H2O2 → Fe2+ + HOO• + H+

    The free radicals generated by this process then engage in secondary reactions. For example, the hydroxyl is a powerful, non-selective oxidant. Oxidation of an organic compound by Fenton's reagent is rapid and exothermic and results in the oxidation of contaminants to primarily carbon dioxide and water.[2]

    Reaction (1) was suggested by Haber and Weiss in the 1930s as part of what would become the Haber–Weiss reaction.[3] Iron(II) sulfate is typically used as the iron catalyst. The exact mechanisms of the redox cycle are uncertain, and non-OH• oxidizing mechanisms of organic compounds have also been suggested. Therefore, it may be appropriate to broadly discuss Fenton chemistry rather than a specific Fenton reaction.

    In the electro-Fenton process, hydrogen peroxide is produced in situ from the electrochemical reduction of oxygen.[4]

    Fenton's reagent is also used in organic synthesis for the hydroxylation of arenes in a radical substitution reaction such as the classical conversion of benzene into phenol.

    (3) C6H6 + FeSO4 + H2O2 → C6H5OH

    A recent hydroxylation example involves the oxidation of barbituric acid to alloxane.[5] Another application of the reagent in organic synthesis is in coupling reactions of alkanes. As an example tert-butanol is dimerized with Fenton's reagent and sulfuric acid to 2,5-dimethyl-2,5-hexanediol.[6]

    Biomedical applications
    The Fenton reaction has importance in biology because it involves the creation of free radicals by chemicals that are present in vivo. Transition-metal ions such as iron and copper donate or accept free electrons via intracellular reactions and help in creating free radicals. Most intracellular iron is in ferric (+3 ion) form and must be reduced to theferrous (+2) form to take part in Fenton reaction. Since superoxide ions and transition metals act in a synergistic manner in the creation of free radical damage, iron supplementation must not be done in patients with any active infections or in general any diseases.[7]

    Henry John Horstman Fenton (18 February 1854 – 13 January 1929) was a British chemist who, in the 1890s invented Fenton's reagent,[1] a solution of hydrogen peroxide and an iron catalyst that is used to oxidize contaminants or waste waters. Fenton's reagent can be used to destroy organic compounds such as trichloroethylene (TCE) andtetrachloroethylene (PCE). Born in London, Henry Fenton was educated at Magdalen College School, King's College London and Christ's College, Cambridge.[2] He became the university demonstrator in Chemistry at Cambridge in 1878, and was University Lecturer in Chemistry from 1904 to 1924.

    References:
    1.      Fenton H.J.H. (1894). "Oxidation of tartaric acid in presence of iron". J. Chem. Soc., Trans. 65 (65): 899–911. doi:10.1039/ct8946500899.

    2.      http://geocleanse.com/fentonsreagent.asp

    3.      Haber, F. and Weiss, J. (1932). "Über die Katalyse des Hydroperoxydes". Naturwissenschaften 20 (51): 948–950. doi:10.1007/BF0150471.

    4.      Juan Casado,Jordi Fornaguera,Maria I. Galan (January 2005). "Mineralization of Aromatics in Water by Sunlight-Assisted Electro-Fenton Technology in a Pilot Reactor". Environ. Sci. Technol. 39 (6): 1843–47. doi:10.1021/es0498787. PMID 15819245.

    5.      Brömme HJ, Mörke W, Peschke E (November 2002). "Transformation of barbituric acid into alloxan by hydroxyl radicals: interaction with melatonin and with other hydroxyl radical scavengers". J. Pineal Res. 33 (4): 239–47. doi:10.1034/j.1600-079X.2002.02936.x. PMID 12390507.

    6.      E. L. Jenner (1973). "α,α,α',α'-Tetramethyltetramethylene glycol". Org. Synth.; Coll. Vol. 5, p. 1026.

    7.      Robbins and Cotran (2008). Pathologic Basis of Disease - 7th edition. Elsevier. p. 16. ISBN 9780808923022.

    ----------------------------------------------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------------------------------------------------------------              ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    Acknowledgement: Girija Girish Tambe of  Vaishnavi  Xerox helped for Collection of images in the Science Spectrum of  5 September, 2015.   All the mistakes in the collection of information from website, it’s compilation and communication belongs exclusively to :                            

       Vitthalrao B. Khyade (And not to his pace making Shardanagar). Please do excuse for the mistakes.                                                                                                                                                                                                                                

     ----------------------------------

    ------------------- Dr.APIS@World.Science.   -----------------------------------------------------------------------

                                     File: Dr.APIS.5.Sept@Fenton.Reaction                                                                                                      

    Compiled for: Science Association, Shardabai Pawar Mahila Mahavidyalaya, Shardanagar (Baramati) – 413115 India.

      With the Best Compliments From:  Shardanagar (The Agro – academic Heritage of Grandsire Padmashri Dr. D. G. Alias Appasaheb Pawar).

                                                                                    All the mistakes in the collection of information from website, it’s compilation and communication ( through email ) belongs exclusively to :  Vitthalrao B. Khyade (And not to his pace making Shardanagar).                                                                                                           

  • Timothy A Ebert added an answer in Multivariate Data Analysis:
    In case of multivariate normality if the data not normal. Can I ignore the normality and continue analysis?

    Excuse me, I need literature to support that " In case of multivariate normality if the data not normal the researcher can ignore the normality and continue analysis ?". 

    Thanking you

    Timothy A Ebert · University of Florida

    A better question would be "how do departures from the assumptions of the model influence model performance?" You could also ask "does my data depart from normality to such an extent that I am unwilling to accept the outcome?" It is nearly given, that with a large enough sample size all data will depart significantly from normal.

    In factor analysis (Proc Factor in SAS) we have the following choices:

    1) There are nine methods for factor analysis.

    2) There are six methods for selecting priors (not related as far as I can tell to the priors used in Bayesian methods)

    3) There are eight rotation methods.

    In Proc Calis (the SAS procedure for confirmatory factor analysis: http://support.sas.com/documentation/cdl/en/statug/65328/HTML/default/viewer.htm#statug_calis_examples43.htm)

    I think it has the same options, but there are then additional features that enable more specific tests of hypotheses.

    So you will need to figure out which models are appropriate, and the strengths/weaknesses of the different approaches. From the reasonable approaches, are there differences in the results when you try different models?

    This is not a game of try to find the model that gives you the answer that you want. Rather think of this as a game where you see how many solutions there are. If only one is present, then use the simplest model and explain that other models were tried. If there are multiple outcomes then you will need to show at least two of them. If necessary, you can include "supplemental material" that shows an alternate interpretation of the data.

  • Helena Pestana added an answer in Correlation Analysis:
    Should you implement correlation before or after factor analysis?

    I have a questionnaire to analyze. The questionnaire consists of 72 questions . the dependent variable is one question while the independents variable are remaining 71 question. I would like to know which one of these question has significant correlation with dependent variable. So should iimplement factor analysis before or after the correlation analysis to know the underling factor who has relationship with dependent variable 

    Helena Pestana · ISCTE-Instituto Universitário de Lisboa

    Dear all,

    1) In my opinion, the choice of IV depends on the theory you have about its effects on DV.

    2) The problem is that when you use FA you  simplified your model because you summarize the IV's  that must be correlated with each other (then you have to know waht are those IV that are correlated...but also they should be metric to aplly FA. If they are ordinal you could transform your scale for a 0 to 10 and then treat your IV as metrics).

    3) another problem is that as FA analyse means then your IV should be mertric

    4) for the relationship between categorical variables you could aplly the analyse of contingeny tables and use Chi_Squre tests, or if there are interaction effects you could aplly logistic models.

    Helena

  • Kate Lyn Sheehan added an answer in Fascia:
    Has anyone heard of adult mites living behind the eyes of birds?

    I recently performed a necropsy on a waterbird from coastal California and after removing the eyeballs, found hundreds of adult mites within the orbital fascia. The location was no where near the lacrima structures (if that is what they are called in birds). I would greatly appreciate any references where this has been previously reported. Thanks!

    Kate Lyn Sheehan · University of California, San Diego

    These are most definitely not worms and are arachnid adults - mites with 8 legs. Keep the answers coming! 

  • Sirlei Antunes Morais added an answer in DNA Amplification:
    What is the best method to extract DNA from preserved mosquitoes on naphthalene (dry) for a long time?

    I have succeeded in extracting DNA from mosquitoes kept on silica or freezer, using appropriate kits. However, in the older samples and preserved on naphthalene, the extracted product is inadequate for DNA amplification and sequencing. Any suggestions for the optimization of an extraction protocol?

    Sirlei Antunes Morais · University of São Paulo

    I'm adding information here for those who are following this question: During maceration of mosquitoes, the reaction is replaced by an aspect of rust. I think the naphthalene (aromatic hydrocarbon) residue can oxidize on contact with water. In that case, it could destabilize the progress of the next steps of DNA extraction reaction. So, I will try to add 50 to 100 mM DTT (Dithiothreitol) in the first step. This product is a reducer. If it works, I'll put here ...

  • Marina Dore asked a question in Marine Sediments:
    What are the interferences in mercury analysis in marine sediments using Cold Vapor Atomic Fluorescence Spectrometer (CVAFS)?

    What can cause a false positive result?

  • Julie Fisher asked a question in Editing:
    How do I edit a publication already listed?

    How do I edit a publication that is already listed under my name?

  • Alfonso J. Rodriguez-Morales asked a question in Burkitt's Lymphoma:
    Is there any relationship between Chikungunya infection and the risk of development of some types of cancer?

    Since 2000, and probably before, some studies have linked CHIKV infection with some forms of cancer, such as endemic Burkitt's lymphoma, and more recently (2015) with prostate cancer as aggravating co-morbidity. Nevertheless, is not clear to me these relationships and its importance, also considering the potential impact in the context of large LatinAmerica's epidemic with so far over 1.5 million cases reported since ending-2013 up to middle-2015. Any thoughs? more studies? evidences? observations? suggestions?

  • Helena Pestana added an answer in Likert Scale:
    I have used SPSS to analyze my data and the KMO value is .848 which is positive, I am would like to ask what does this mean for my survey tool?

    This tool was created by me as a way to measure students thoughts on cultual capital (embodied) for this one specifically. The questionnaire is 25 questions on a likert scale of strongly disagree, somewhat disagree, disagree, maybe, agree, somewhat agree, and strongly agree.

    Helena Pestana · ISCTE-Instituto Universitário de Lisboa

    Dear Pamela, 

    Kaiser-Mayer_Olkin Measure of sampling adequacy (=KMO) is a statistical procedure which allows the measurement the quality of the correlations between variables in order to be able to continue with the factorial analysis. KMO varies between 0 and 1 and compares the zero order correlation with the partial correlations observed between the variables.

    The KMO close to 1 indicates small partial correlation coefficients while values close to 0 indicate that the factor analysis can not be a good idea because there is a weak correlation between the variables. Kaiser adjective values KMO as they are:
    i) between 1 to 0.9 very good FA; 0.8-0.9 AF good; 0.7-0.8 FA medium; 0.6-0.7 AF reasonable; 0.5-0.6 AF bad; <0,5 FA unacceptable.

    Have a nice time

    Helena

  • Alfonso J. Rodriguez-Morales added an answer in Mayaro Virus:
    Are there studies about Mayaro virus in Colombia and other Andean countries, in addition to Venezuela?

    With the expansion of Aedes-borne diseases, such as Dengue and Chikungunya, there would be also concern about Mayaro and Zika viruses in countries such as Colombia.

    Alfonso J. Rodriguez-Morales · Universidad Tecnológica de Pereira

    Thanks Jonas. Good answer.

  • Jeffrey P. Buzen added an answer in Server:
    Does changing service discipline in a queue has an effect on utilization of the server, and what about effect on queueing networks also?

    from example, changing service discipline from FCFS to SPT. I know that it affects average waiting time, but about the utilization of server. I think that it has no effect on single queue, but what about a queueing network?

    Jeffrey P. Buzen · Rethinking Randomness

    Utilization is always the product of average throughput rate and average service time (see my old "Fundamental Laws" paper from 1976 or any text on queuing theory with a section on Operational Analysis or Operational Laws).   For a freestanding queue, average throughput rate (usually the same as average arrival rate) and average service time are fixed parameters of the model.   In such cases, utilization is always the product of these two parameters and is thus completely independent of the order in which requests for service are processed (i.e., the service discipline). Thus, your conclusion for a "single queue" is correct. 

    On the other hand,  service discipline can affect average response time.   If a queue is part of a closed network, improvements in  average response  time can result in positive feedback that leads to higher overall throughput rates for some or all servers in the network.  This in turn can lead to higher utilization at these servers. This is the answer to your second question.   For more information about the theoretical foundations for all this, see my new book, Rethinking Randomness, which became available on Amazon last week.

    Jeff Buzen

  • Michael Medvinsky added an answer in Boundary Value Problem:
    How do I solve the following Laplace boundary value problem?

    I am concerned to solve the following Laplace boundary value problem. Although it seems so simple, I couldn't find the solution using separation of variables method. Please see the attached file for problem statement.

    Michael Medvinsky · University of Utah

    You should be able to find the solution using separation of variables. Be more specific if you need help.

  • Sofia D. Wechsler asked a question in Quantum Entanglement:
    Is it justified to consider moving frames when analyzing quantum entanglements?

    In working with entangled particles we use to test them simultaneously. Consider for instance a pair of entangled particles. The meaning of the word "simultaneously" is not that the two particles are tested at exactly the same time with infinite time-precision. To the contrary, since the moment when one of the particles is detected, the other particle is detected within the pair-coherence interval, τ_{pair}. Outside this interval what we detect is particles from different pairs. The order of magnitude of τ_{pair} for down-conversion photons is the same as the coherence time of the single photons.

    But, what becomes τ_{pair} when judging according to moving frames? In a frame F_A which moves in the direction from Alice's lab to Bob's lab, it is likely that τ_{pair} becomes two-fold. That means, one value for Alice's particle and another value for Bob's particle.

    I think - and I am not sure - that for Alice's particle τ_{pair} appears as shorter and for Bob's particle as longer. And the faster is the movement of F_A, the longer appears τ_{pair} for Bob's particle. Does such a situation has physical meaning, is this an entanglement anymore?

  • Umana Itaketo added an answer in Control Systems:
    How can I design the parameters of PI controller in a control system?

    As we design a controller of PV gridconnected system to track a certain signal,such as a current inner loop and a voltage outer loop,what is the basis to determine the parameters of PI controller?What the relationship between the proportional & integral constant and the generated current error or voltage error?I am looking forward to your help!Thank you very much!

    Umana Itaketo · University of Uyo

    You may approach this problem by simulating the controller with various combinations of P and I simultaneously and watching the output for the key response parameters of interest. This could be maximum overshoot (which should be low), rise time (which should be low), and the most important, (settling time) which should be low. The  combinations of P and I that give the optimum output response would be the those you can use for the design of the controller.