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  • Jacques Lavau added an answer in Quantum Mechanics:
    Help with Feynman's(thought) experiment with electrons?

    I read his description of the experiment but I still haven't understood as to how the results can't be predicted with "classical physics", what I mean is that electron gun which he has assumed throws out electrons randomly and since we do not know the initial conditions( because of randomness) we can't predict the exact trajectory , and therefore we can talk  only of probability, but I see that Feynman says constantly that "we can't really predict where the electron would end up being" but ain't that because of the random nature of electron emitting device??

    Obviously i am wrong somewhere but I can't catch it?

    Any help would be appreciated.

    Now Feynman has constantly  

    Jacques Lavau

     @Charles Francis. So it has spin, and both retrochronous and orthochronous abilities. And you pretended it cannot have spin.

  • Azzam K Almosallami added an answer in General Relativity:
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Azzam K Almosallami

    There is no dark matter or dark energy..all of that explained in my model. Also according to my model there are no infinities or singularities, they are removed. Review my paper http://vixra.org/abs/1509.0059 Furthermore CMB anisotropy explained by removing the reciprocity principle according to my transformation.

  • Lars Ahnland Nordfors added an answer in Time Series Econometrics:
    Can I correlate two time series in levels?

    Hi! This might seem like a dumb question, and it probably is. I´ve red a little time series econometrics and have come to learn that you can´t compare non-stationary series (unless there is cointegration). Then I came a across a paper where the authors correlated two series in level, and I became confused. The answer from the author was that "We can do this since we don´t try to establish Granger causality". Is this allowed???

    Lars Ahnland Nordfors

    What if the relationship is dialectic/bidirectional?

  • Hossein Soleimani added an answer in Images:
    Can entropy of contrast enhanced image be greater than the original image?

    Can histogram equalization increase the entropy of an image?

    Hossein Soleimani

    We are talking about entropy of an image after and before histogram equalization and not contrast enhanced image.

    contrast enhanced image may  be like sharpened image. This operation absolutely decreases Entropy.

  • Mustafa Tekke added an answer in Islam:
    Is there anyone can explain about plurality of religion? And what is the biblical explanation abour plurality?

    I want to write about the relation between Islamic and Christianity in plurality of religion.

    Mustafa Tekke

    Hope attached is useful for your investigation.

    • [Show abstract] [Hide abstract]
      ABSTRACT: Drawing on in-depth interviews and ethnographic data, this article provides one of the first empirical analyses of religious classes for converts in the United States. Focusing on “new member classes” in two religious communities (a Muslim association and an evangelical Christian church), we introduce the concept of “pedagogies of conversion” to describe how religious organizations teach converts about their new religion and set up guidelines to frame the conversion process. By examining the pedagogical tools that religious instructors use on a daily basis to foster spirituality among new members, we investigate how converts learn to become religious people. We demonstrate that while there are significant differences in the doctrines (know-what) being taught in the Muslim and evangelical classrooms, the tips and pieces of advice delivered by instructors on how to be religious (know-how) are strikingly similar.
      No preview · Article · Dec 2015 · Sociology of Religion

    + 1 more attachment

  • David Mathuva added an answer in Corporate Strategy:
    Does name change improve financial performance of the firm?

    A number of studies have examined market reaction to name changes, Cole et al. (2015) examines impact of insurer name changes on growth in premiums, which is a component of income. However, sparse literature exists on impact of name change on financial performance. What do you think would be the impact of corporate name changes on the bottom line? Please share your thoughts..

    David Mathuva

    @Warren, Robert, Jaharkanti, and all who contributed to this thread of discussion, I am happy to inform you that a paper on the impact of name change on financial performance of savings and credit cooperatives in an emerging economy that I had been working on has been accepted by Emerald's Management Research Review and should be sharing the findings in due course. Part of the findings reveal a positive association between name change and financial performance as measured by return on assets and operating profitability. However, the study finds that the impact of name change seems to be felt about 4 years after the name change. This is, of course, after controlling for a number of other firm-specific and exogenous factors among a set of robustness checks. @Warren, in the study, the adjusted R-squared is much better than Cole et al.'s and is >30% in all estimation models. What are your reactions to these findings? 

  • Sohel S Shaikh added an answer in Biotechnology:
    Please, suggest me a method for screening cellulose-degrading bacteria?

    I am using CMC media for culturing cellulose-degrading bacteria and using 1% congo red, 1M NaCl.

    Sohel S Shaikh

    use minimal medium contaning carboxy methyl cellulose (CMC) assole sourse of carbon.

    After incubation fill the plate with congo red foklwed by NaCl. Colony having ability to hydrolys cellulose will zone clear zone against red background 

  • Francis Taale added an answer in Tourism, Economics and Development:
    What are the links between tourism and poverty, and how can tourism be used as a tool for poverty reduction?
    I want to link poverty with tourism, kindly contribute. What are the roles of all stake holders in achieving poverty reduction among host communities?
    Francis Taale

    it very much depends on the local dynamics. Tourism is a derived good and it would be very strange for anyone to believe that it leads to economic growth and poverty reduction. Tourism gets the opportunity to contribute to economic growth and development when other sectors of the economy have grown and led to a higher incomes and mass prosperity which then causes locals to desire places to sight-see and rest. I have the firm believe that tourism should not be considered a determinant of economic growth but rather a by-product of economic growth. Technology, good education and domestic policies as well as fair trade and international relations are the factors of economic growth, poverty reduction and development. How tourists or tourism can reduce poverty remains a controversy. They have aided the poor in some  countries but have raided the poor in other countries.

  • Carlos Eduardo Maldonado added an answer in Catholic Church:
    Was the University an European invention at hands of the Catholic Church?

    Please, provide your thinking about this question. Thank you.

    Carlos Eduardo Maldonado

    Pushing a little bit farther András' comments, one can also easily see some religious biases on some answers, rather than strictly logical or historical replies.

  • Barzini Barzini added an answer in Gallium Nitride:
    What would be the ideality factor of a Gallium Nitride based solar cell diode?

    I am trying to simulate Gallium Nitride based pin solar cell with Indium Gallium Nitride quantum dots ambedded in the intrinsic region. Can anyone help me with supporting resources?

    Barzini Barzini

    [kickass.so]silvaco.2014.setup.crack.for.study.version THIS IS THE TORRENT OF SILVACO

  • Ahmed Abass asked a question in Transition Metal Complexes:
    Which is the suitable software for XRD analyzing for new compound?

    Hello all

    I prepared new transition metal complexes and i need for free XRD software for pc to analyze the new compounds (unknown) to give many parameters such as the structures, unit cell, lattice parameters, miller constants and other. 

    Thank you all

  • Allauddin Memon Kohistani added an answer in Creative Thinking:
    What are the psychological reasons the child age of 5 to 10 years mostly break the toys after playing few days..?

    I was thinking the creative thinking of the child from his birth How the observe the things and when they reach up 2 to 3 years of age they start asking of Questions from their parents Like Scientists why,who and how...?And I observe most of children break the toys after playing few days But I can't find the complete answer So I want to try ask the Question from the Researcher for A better Answer And Finding the conclusion...

    Allauddin Memon Kohistani

    Thanx for answering I also believe in that philosophy some time ago but  When try to find the facts I wonder on the nature in Reality there more hidden truths than that There huge psychological reason behind It.....I hope also you will try to find.....The question debut able and  I believe Every child has especial capabilities and that is the reality..........................................................And I want some research or research papers on the topic..............

  • Yurii V Geletii added an answer in Activation Energy:
    How spontaneous fission takes place?

    Here I want to know the mechanism of spontaneous fission? Does the concept of activation energy doesn't play any role and if it does, from where the activation energy is supplied?

    Yurii V Geletii

    What is a fission? Nuclear? What is the reaction?

  • Kamal Mohammedi added an answer in Quadcopter:
    Can anyone help me to get connected ZANO quadcoper to my phone?

    ZANO connectivity registeration problem

    Kamal Mohammedi
    It seems that you are not the only one having trouble with ZANO quad.......
  • Ebot Walter Ojong added an answer in pH:
    How can I dissolve commercially available LDL lyophilised powder?

    I have tried PBS (pH 7.4), tris-glycine buffer (7.4) and I still can't get a full dissolution of LDL.

    Ebot Walter Ojong

    Most commercial supplies provide an Assay Diluent for reconstitution of the lyophylized material. Vortex vigorously during recostitution until dissolved.

  • Charles Francis added an answer in Special Relativity:
    Given that we now view spacetime with the metric structure of GR, does it make sense to keep using the reference frames of special relativity?

    SR can now be viewed as general evolving hyperbolic sheets just as in GR.  The Globally rectangular coordinate frames on SR seem to lead to many confused arguments on the nature of SR using antiquated notions.  Should we abandon much of the traditional picture of SR and view it in terms of more general local frames and invariants?

    Charles Francis

    Andrew, whether you like it or not, or express it that way or not, special relativity already uses a 4D manifold. If this had not been so, we would not have general relativity.

    Erkki, general relativity is formulated in such a way as to apply to all coordinate systems, including all those we would like to use and all those we would never even dream of using as well. Curiously, once one has come to terms with the additional level of abstraction, this actually makes it easier, because one has no distraction due to the special properties of any particular coordinate system.

  • Vladimir A. Kulchitsky added an answer in Political Socialization:
    Who is a sycophant? Is sycophancy an Art?

    We see sycophants in all the fields - political, social, administrative ......

    Do you think it is an art that is harmless or something that harms the organisational culture severely.   

    What kind of sycophants are prevalent in your part of the world.

    Vladimir A. Kulchitsky

    Dear Krishnan! It is precisely with elements of sarcasm you have defined the essence of flattery.

  • Alexander J. Babchin added an answer in Tsunami:
    What kind of damage can cause nuclear undewater exposion 50-100 MGT in the middle of atlantic ocean on 42 paralel North ?

    Duing it on the ocean bottom at 1 km depth the explosion will cause enormous high pressure boiler 10 or more km in diameter, causing tsunami wave 500 m or more in high, propagating circularlly with speed about 800 km/hour. Such a wave hit Alaska in 1958 and was caused by reletevely modest eartquake. This wave is capable to run on the distance up to 20 km overland, completely engolfing sea sides cities and their inhabitants.

    In the case such an explosion will by done in the middle of Atlantic ocean at 42 parallel North,the tsunami will destroy all costal cities of North America and Europe alike.

    Inland countries, or countries connected with open ocean by narrow straights are immune to this effect. Also, Arctic ocean will dump this kind of tsunami in short distance, due to ice crust.  

    Alexander J. Babchin

    Visually no nuclear explosian is expected to be observed, as all energy released will be spent on transforming water into the steam, which will erupted from the ocean on the hight of several kilometers. Upon steam condensation and fall back, the serias of tsunamis will start their run in radial direction. The similar effect can be expected in underwater vulkano eruption, like near Alaska in 1958 event. 

  • Rumit Maini added an answer in Cell Line Culture:
    I am looking for cell lines and how to work with them, which expresses TrkB (tyrosine kinase receptor) cell membrane receptor found on neural cells?

    I need to study TrkB binding with its ligand BDNF. I wish to use a phosphorylation detection kit to see dimerization and phosphorylation of TrkB upon BDNF binding. For this, I need cell lines expressing TrkB along with a protocol to work with them. I have experience working with E coli cells, but not with any human cell lines. I know HEK293 have been used in similar studies and are commercially available. I am unsure if they express TrkB on their own or we need to do further work. 

    Looking for answers!

    Thanks in advance.

    Rumit Maini

    Hi Jason,

    Thanks for the help and link. I tried following as you described and got some charts with various color codes. Unfortunately, I am unable to follow it.

  • Vladimir Onoochin added an answer in Force:
    Any suggestions on a puzzle of gravitational 'perpetuum mobile'?

    I wish to offer one puzzle. Let us consider a thought design of one device (in principle, this device can be made).

    The device consists of the wheel rotating with high speed. Four bodies of masses m are mounted on the rim of the wheel. The supporting rods are assumed to be of negligible small masses. A number of bodies can be bigger ; the only condition is that the bodies should be mounted symmetrically with respect to the axis of rotation. The axis of the wheel is non-moving (fixed) and another body of big mass M (M ~ 4m) is mounted at the lower end of the axis. Mass of the rod which is the axis is negligible small too.

    In accordance to the general relativity, the gravitational force between the lower body (l.b.) and every rotating body (r.b.) is
    where G is the gravitational constant, R the distance between the bodies.
    F_{r.b.->l.b.}=G\frac{Mm}{R^2}\left(1 - (v^2/2c^2) \right)
    So we have non-compensated force
    \Delta F = G\frac{Mm}{R^2}* (v^2/2c^2)
    Obviously, this non-compensated force acts along the axis. Because it is assumed that the system doesn't lose energy (the gravitational radiation should of the order of (v/c)^5), and under assumption we eliminate all effects of friction, this system should self--accelerate, i.e. its energy is growing with time.

    The first puzzle: what is the source of this growing kinetic energy of the device?

    I should say that in similar electrodynamical system a paradox of non-conservation of the energy is absent - the radiative losses are of order of (v/c)^2

    Vladimir Onoochin

    It is no difference if I am near or far from the Darwin Lagrangian. The expression for the E field is right.
    The acceleration of the electron moving with |v| = const is only centripetal acceleration and it is equal to v^2/R
    Because the Darwin potentials contain no retarded quantities, there is no problem to choose the frame. The only requirement is that it should be inertial.

    If you don't know how to calculate the derivatives of the Darwin potentials, you should look at the paper of L. Page and N.I. Adams, Jr., Action and Reaction Between Moving Charges, Am. J. Phys. v. 13, 141 (1945). Their Eq. (3) is the same I use. The Lagrange approach 'ignores' acceleration o f the source - it is only to explain the difference in there approaches.

  • Yurii V Geletii added an answer in Catalyst:
    What is the limiting factor in CO2 reduction by electricity?

    There are some reports on reducing CO2 into fuel chemicals but the efficiency is quite low. What do you think is the limiting factor of CO2 reduction? We have to identify the rate-limiting factor in order to improve the efficiency.

    Factors involve in this process include cathode and anode material, interface, catalyst/enzyme, ion exchange membrane, CO2 solubility, product specificity, etc.    

    Yurii V Geletii


    First, the solvents you mentioned are not suitable for electrochemistry.

    Second, in aqueous solutions water is oxidized on anode  to O2 producing protons. which are then used on cathode to hydrogenate CO2.  A solvent is involved  in overall reaction.  E.g. if you use CH3OH as a solvent, you will oxidize CH3OH on anode to CO2 and reduce CO2 on cathode to CH3OH

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub


    in retinoid theory, unconscious subjectivity is an incoherent concept.

  • Victor F. Medina added an answer in Molecular Biology:
    Does anyone know of a resource to get feedback on a working paper in the area of phytoremediation?

    My working paper models arsenic uptake by ferns under a variety of conditions and is titled "Risk Analysis for Arsenic Removal from Bangladesh Drinking Water through Phytoremediation by Chinese Brake Fern (Pteris vittata L.)”

    Victor F. Medina

    A review article that might be helpful:


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Phytoremediation is a promising new technology that uses plants to degrade, assimilate, metabolize, or detoxify metals, hydrocarbons, pesticides, and chlorinated solvents. In this review, in situ, in vivo and in vitro methods of application are described for remediation of these compounds. Phytoaccumulation, phytoextraction, phytostabilization, phytotransformation, phytovolatilization and rhizodegradation are discussed and the role of enzymes in transforming organic chemicals in plants is presented. The advantages and constraints of phytoremediation are provided. Our conclusions is that phytoremediation prescriptions must be site-specific; however, these applications have the potential for providing the most cost-effective and resource-conservative approach for remediating sites contaminated with a variety of hazardous chemicals.
      Full-text · Article · Jun 2002 · Ecological Engineering
  • Ferenc Hörcher added an answer in Ethics:
    Any methods of combining descriptive and normative ethics?

    I am interested in the combination of descriptive and normative elements in moral reasoning.  To put it differently, I am interested in theories which try to integrate empirical data on moral experience/attitudes/judgments with ethical reasoning. Could you recommend some good rudimentary literature on it (except reflective equilibrium)?

    Ferenc Hörcher

    Dear Krzysztof,

    have you tried to look at natural law theories. They claim to disregard this (Kantian) distinction.



  • Noura Darwish added an answer in Lysis Buffer:
    How can I confirm the presence of cDNA in sample?

    please if you can help me about my experiment: I did RNA extraction from 2 ml whloe blood by using ammonium chloride lysis buffer then used 1 ml TRIazol reagent for pellet, stored my samples for 4 month at - 80 oC

    then did cDNA at the same day of extraction with out measuring RNA conc in sample i used 10 microleter of RNA for each cDNA reaction.

    then i did q PCR with out diluting c DNA but i have no result 

    How could i confirm the success of cDNA synthesis?

    is there any method to measure c DNA in sample before qPCR?

    Noura Darwish

    i actually did normal pcr for random samples using GAPDH primers and negative control to exclude the presence of gDNA and found the following results attached here

    can anyone help me to understand the results?/

  • Daniel Ejebe added an answer in Rabbit:
    What is the most effective way to avoid interference from the heavy chain of IP antibody in the IP:WB?

    I am thinking that choosing the IP antibody from a specie different from that used as primary and secondary antibodies during the IP western blot is the way to go i.e  mice IP ab/rabbit primary ab/ anti rabbit secondary ab or rabbit IP/mouse primary/ anti mouse secondary.

    Daniel Ejebe

    Thanks Sayed, the question then arises what determines species specificity? Is it both linear and conformational epitopes? Or conformational epitopes alone? The answer to this will support Jordan's suggestion that my proposed approach is unlikely to work.

  • Avinash Patel added an answer in 3 Dimensional:
    How can i find Third point in triangle with two coordinates and lengths known in 3 Dimensional system?

    i am working on a project of 6 D.O.F simulator with stewart platform and i have angles between crank and links but i want to find the vertices of crank end point.also have lengths of crank and link and vertices of base and platform.

    + 1 more attachment

    Avinash Patel
    sir , this is 2 dimensional i also require z co-ordinate how can i find that?
  • Anil Prakash added an answer in Mosquitoes:
    What is causing death in 2nd and 3rd instar larvae?

    This question goes out to anyone rearing mosquitoes in their labs. Have you ever encountered the following problem:

    The larvae hatch fine and look normal. However, once they reach 2nd/3rd instar stage, they develop a dark spot in the middle of their body (as if something is blocking their digestive trackt) and most of them die.

    Apart from a bit of bacterial growth (which was never a problem before), the water looks just fine.

    We're at a loss at the moment and would appreciate any suggestions as to what might be the problem.


    Anil Prakash

    There could be the problem of infection with Lambornella spp, a Hymenostome endoparasite, in your colony. This infection had once wiped off my entire colony of Anopheles stephensi......Please beware of

  • David Mathuva added an answer in Aspirate:
    What is the basic aspiration of human being ?

    What is the basic of human being? 

    This is my open ended study? Please answer as you can. Thank you 

    David Mathuva

    Happiness, the desire to seek happiness

  • Ebot Walter Ojong added an answer in Medical Applications:
    What are the effects of limonene?

    Could it be the effects of limonene the following?
    The D-limonene is also a possible candidate for a variety of medical applications, including cancer and AIDS, and has been noted to have insecticidal properties. In fact, recent studies seem to reveal that limonene has anti-cancer properties. Increases the levels of liver enzymes used in the neutralization of carcinogens. Limonene apparently promote the system GST (glutathione-S-transferase, involved in eliminating carcinogens) of the liver and intestines and balance out caused by carcinogens. Animal studies show that limonene has properties chemioprenventive in cancers and if present in the diet reduces breast tumor growth.

    Ebot Walter Ojong

    The naturally occurring monoterpene d-limonene has chemopreventive and chemotherapeutic activity against many rodent solid tumor types. The chemopreventive activity of limonene during initiation can be attributed to the induction of phase I and phase II enzymes, with resulting carcinogen detoxification. The chemopreventive activity of limonene during promotion/progression may be due in part to inhibition of the posttranslational isoprenylation of growth-controlling small G proteins, such as p21ras. The complete regression of mammary carcinomas by limonene appears to involve tissue redifferentiation. The multiple antitumorigenic effects of limonene are attainable at a high therapeutic ratio, suggesting that limonene and related monoterpenes may be efficacious in the chemoprevention and chemotherapy of human malignancies.