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  • Is there a solid counter-argument against Dingle's old objection to Relativity Theory?
    Herbert Dingle's argument is as follows (1950):

    According to the theory, if you have two exactly similar clocks, A and B, and one is moving with respect to the other, they must work at different rates,i.e. one works more slowly than the other. But the theory also requires that you cannot distinguish which clock is the 'moving' one; it is equally true to say that A rests while B moves and that B rests while A moves. The question therefore arises: how does one determine, 3 consistently with the theory, which clock works the more slowly? Unless the question is answerable, the theory unavoidably requires that A works more slowly than B and B more slowly than A - which it requires no super- intelligence to see is impossible. Now, clearly, a theory that requires an impossibility cannot be true, and scientific integrity requires, therefore, either that the question just posed shall be answered, or else that the theory shall be acknowledged to be false.
    Stephen Crothers · Alpha Institute of Advanced Study

    F. Leyvraz: You continue to talk falsehoods. Time is not defined or created by units of its measure. It exists a priori to any units of measure invented to measure it, just as distance between places exists a priori to the invention of units of measure to measure it. Time and distance did not suddenly spring into existence when people invented instruments to measure them. Instruments to measure and units of measure were invented to measure that which exists independently of the fancies of Man.

    Your claim that my remark, "Physics is guided by experiments, not mathematical fancies. How many experiments are sufficient to invalidate a theory? One is sufficient.'' is false, is nonsense. Physics is guided by experiment, for otherwise it does not deal with the physical Universe.

    I have already stated that ALL experiments that show that the energy and momentum of a closed system are conserved refute General Relativity. Such experiments constitute a vast array. Do you deny that all the experiments that reveal conservation of energy and momentum for a closed system are false? If so, you had better have good reason to maintain that, and explain to all here why all these experiments are invalidated by General Relativity, rather than the opposite.

  • Graham Pulford added an answer in Object Tracking:
    Can any one refer me current state of art methods for non-linear and non-gaussian modelling of bayesian network for object tracking applications?

    conventionally, kalman filters were used for the purpose of tracing applications in image processing field, but now the trend is moved to non-linear & non-gaussian assumptions of state & measurement models.

    Graham Pulford · Thales Group

    There are many methods for dealing with non-linear/non-Gaussian estimation problems in tracking. An introduction to different tracking techniques can be found in my IEE 2005 survey paper, which covers the material prior to the growth of particle filters and FISST/PHD filtering work, which is now very popular. Gaussian mixtures is another popular framework, but you should always tailor the solution to the specific problem. EKF or iterated EKF, UKF, mixture model, particle filter, etc. They all have their advantages and disadvantages. A good idea is to implement two or more and see what works best for your problem and data. Bear in mind that PHD methods typically provide unlabelled tracks in the case of multiple objects. The other point I will make is that the non-linearity has to be fairly severe (compared with the sampling time) to justify the use of the more advanced methods over simple schemes like EKF. No point using a sledge hammer to crack a nut ;-)

  • What are the applications of the Fibonacci series in the stock market?
    Trends of the finance market.
    Reiner Creutzburg · Brandenburg University of Applied Sciences

    Dear Janamejay,

    I hope the enclosed book is helpful to answer your question.

    Regards Reiner

  • Safwan Shatnawi asked a question in Ontology:
    Why do general ontology learning algorithms fail when they are applied to a subject course content knowledge?

    In a situation where we want to build a subject course ontology using text books, notes, or other teaching resources; general ontology learning algorithm generate poor quality ontology.

    I'm researching this issue and I captured set of possible reasons. Can anyone suggest some reasons based on either authentic research results or his/her experience of this domain?

  • Miroslav Petrzelka asked a question in NoSQL:
    Is security the stumbling block for spreading NoSQL more rapidly?

    The security seems to be a main defending point of RDBMS.

  • Alex Thomas added an answer in Building Performance:
    Which building element plays the most important role in saving energy, when applied in extreme weathers?

    For an instance, which building element should be prioritised during design stage?

    Alex Thomas · Deakin University

    Definitely the facade of the builiding should be given the most care. The orientation of the building must also be taken care

  • Miroslav Petrzelka asked a question in NoSQL:
    Can “Sharding” be the instrument/bridge for cohabitation of RDBMS and NoSQL?

    Where Sharding allows use of regular relational tables with NoSQL collections?

  • What would be the parameters to differentiate the terms Bionics, Biomimetics and Biomimicry?

    The terms were coined by different people in different times, e.g. Bionics by Jack Steele in 1960, Biomimetics by Otto Schmitt in 1960 and lately Biomimicry by Janine Benyus in 1997. There are also similar terms, such as Bio-inspired engineering and sometimes Biognosis. So, they should conceive the terms based on some different parameters at least. For example, if their goals are different what are they?  

    Recently, I have got the following  from a blog of Alena Iouguina "according to Daniel Wahl, ‘biomimicry’ takes its inspiration from principles of ecologically informed design proposed by John Todd and Nancy Jack-Todd of New Alchemy Institute in 1970s. Later expanded on by Fritjof Capra – the founder of Center for Ecoliteracy – these principles of ecology transformed into ‘the language of Nature’ (1994) and caused a perceptual shift in “the link between ecological and human communities”

    In the homepage of Biomimcry Europe I found "We define it as an innovation process encouraging the transfer of ideas, concepts and strategies inspired from the living world, with the objective of designing human applications aiming at a sustainable development."

    Johanna Marie Galloway · University of Bristol

    please see the recent paper from Rawlings et al http://pubs.rsc.org/en/Content/ArticleLanding/2012/SM/c2sm25385b discussing the definition of these terms.

  • What is (are) the difference(s) between public health and community health?
    Some perceive it as the same (semantically) while others view it as different in principle.
    J Perriot · Conseil general du Puy de dôme

    This link is very informative Joan.

  • Govinda Sharma added an answer in PHA:
    What is the mechanism of T cell activation by PHA-L?

    I am trying to work out exactly how PHA-L induces proliferation of T cells. I have search the literature and have so far just found explanations of indirect CD3 cross-linking (but no direct evidence), and a requirement of monocytes/ IL-2.

    I am particularly interested in what ligands PHA is binding on T cell surfaces, and whether there are any reports of PHA binding lectins expressed on T cells.

    It would be great if anybody has more information on this topic, and/or if someone could suggest any relevant literature for me to read.

    Many thanks!

    Govinda Sharma · BC Cancer Agency

    The specific sites of PHA:T-cell interaction seem to still be not well-defined although some literature suggests that PHA initiates activating signals via the CD2 receptor (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1453876/, http://www.ncbi.nlm.nih.gov/pubmed/2484882). In lectin-based T-cell activation, downstream mechanistic differences have been observed compared to antigen-specific activation: lectins cause Ca2+ influx via different combinations of calcium channels than those utilized by CD3-specific signaling pathways (http://www.ncbi.nlm.nih.gov/pubmed/22020731).

  • Curt Renshaw added an answer in General Relativity:
    Will observers accelerating with respect to a stationary charge detect photons?

    If an observer is accelerating with respect to a stationary charge, will he detect any photons? 

    Curt Renshaw · Tele-Consultants, Inc.

    I like Bhushan's analysis. Look at section 7 of the attached article on the effect of a "moving" charge above a current carrying wire.

  • Mohammad Asim added an answer in Yeasts:
    Is it better to express yeast kinases in E. coli or yeast to use in kinase assays?


    I have high copy yeast vectors into which are cloned yeast kinases with a N-terminal GST-His tag under the regulation of a GAL promoter. I need to purify these kinases for kinase assays, and am wondering if I should express them from the yeast vectors directly or is it better to subclone them for expression in E. coli?


    Mohammad Asim · University of Cambridge

    normally E Coli should be OK but I guess if your kinase is a complex one with subunits, I am afraid E coli may not carry out required post translational modifications rendering the expressed protein catalytically dead.

  • Zigang Pan added an answer in Simulink:
    Is there any relation between switching frequency and sample rate or else my control loop is unstable?

    In Simulink I have a model which has a frequency of 40KHz and my sample rate is 25micro seconds for every 25e-6. I have an input for control loop but when I try to change sample rate to milli seconds then it shows drastic results. Is there any relation between switching frequency and sample rate or else my control loop is unstable?

    Zigang Pan · N/A

    Sample rate has to be at least twice of the signal frequency in the system.  

  • Miroslav Petrzelka asked a question in NoSQL:
    Can we use NoSQL for sensitive and confidential data?

    And if yes then why?

  • Miroslav Petrzelka asked a question in NoSQL:
    Do you think that coding around when there is a lack of transactions as needed with NoSQL systems will lead to adoption of NewSQL instead?

    Do you think that coding around when there is a lack of transactions as needed with NoSQL systems will lead to adoption of NewSQL instead?

  • Miroslav Petrzelka asked a question in NoSQL:
    Do you think as NoSQL matures it will become closer to the SQL engine with scaleable, flexible and fault-tolerant replicated database?

    As SQL comes with an expectation that the following functions INSERT/UPDATE/DELETE/CREATE or as it’s called CRUD occur instantly upon a single “global state” it becomes a problem as the NoSQL works with a replicated environment.

  • Miroslav Petrzelka asked a question in NoSQL:
    What is the main problem that prevents a quicker adoption of NoSQL databases?

    Are these problems the ones that are usually involved with new systems, where new skills are needed.

  • Sundarapandian Vaidyanathan asked a question in Cats:
    Can animals have identical twins?

    It is a general query - whether animals can have identical twins, that is, twin babies, which look identical or exactly similar! In the internet, I saw some photos of two similar looking cats etc. What causes identical twins in birth? Kindly enlighten!

  • Miroslav Petrzelka asked a question in NoSQL:
    Do you think that NoSQL databases that do not strongly follow ACID properties may have limited usage in the future?

    NoSQL is highly valued for consistency but is not strong enough to fit a set of ACID properties.

  • Do you feel that living in apartment buildings contribute to social isolation and depression?

    Could an increase in shared facilities (indoor and outdoor - such as gardens) help reconnect residents living in close proximity? Are there other architectural features that could improve this situation? 

    Jacqui B Jeavons · Deakin University

    Thank you very much Deno and Renzo! I really appreciate your leads....

  • Miroslav Petrzelka asked a question in NoSQL:
    Is there any way to make RDBS simpler and can it be made easier to do live upgrades?

    I mean if you use NoSQL than make any upgrades/replace one machine will not have any effect on user due to its distributed nature is RDBS able to behave in similar way in the future?

  • David Yetter added an answer in Ontology:
    What are infinitesimals------- a 2500-year suspended problem?

    The newly discovered modern Harmonic Series Paradox is one of family members of ancient Zeno’s Paradox, it discloses relentlessly a fact that we human still don’t know what infinitesimals are: with or without numerical meanings, zeros?

    Infinitesimals are there in our science, but what are their positions as numbers or non-numbers or something else theoretically and operationally, ontologically and formally?

    This problem has close relationship with whole fundamental part of infinite related area in our science:
    1, theoretical and practical infinite theory
    2, theoretical and practical limit theory
    3, theoretical and practical infinite related number theory

    David Yetter · Kansas State University

    Of course we have rigorous definitions of infinitesimals.  Read

    A. Robinson, "Non-standard analysis" , North-Holland (1966)

    for one definition, and

    A. Kock, "Synthetic differential geometry" , Cambridge Univ. Press (1981)

    for the other.

    In fact, your objections actually have nothing to do with infinitesimals.  Series, whether convergent or divergent, are composed of infinitely many finite summands:  there are no infinitesimals in sight in either your harmonic series objection or Zeno's paradox (which is quite handily resolved once one accepts the modern notion of limit of a geometric series and goes through the exercise of verifying that 1/2 + 1/4 + 1/8 +... = 1 in the sense that the limit of the series is 1, and is thus, quite uninteresting except as a historical curiosity).

  • Does anyone have experience with an extended kalman filter without process noise?

    I am currently working on an extended kalman filter for a nonlinear system.

    And I am very confused.

    Assume there is a nonlinear system without process noise but with measurement noise. Then when using EKF to estimate the state of this system, how can I handle Q in EKF.

    For example:

    x(k+1)= x(k) ; or x(k+1)= x(k) + u(k)

    and observer equation
    y(k)=x²(k) + v(k)

    u(k) is the input and v(k) is the measurement noise.

    When EKF is used for the estimate of the state, should I set Q=0? 

    Graham Pulford · Thales Group

    You don't always have to have Q>0 in a Kalman filter in practice and often Q can be very small. It is helpful to think of Q as a tuning parameter for the Kalman filter with small values tending to ignore the data and large values following minute variations (high gain). Q also has implications for the convergence of the matrix Riccati equation that governs the estimation error covariance. Q governs controllability of the linearised system and hence the positive definiteness of the steady state covariance. The theory is mostly for the KF but there are some results around for the EKF (I think).

  • Ichun Chen asked a question in Adipose Tissue:
    How to harvest pericardiac fat tissue?

    We have been trying to harvest the pericardiac adipose tissue from mice, but we turned out to resect thymus after we send the specimen for microscopic analysis. Do anyone has experience in this procedure or can provide some online video if you find some?

    I found one on JOVE. But, the video did not get into the details about pericardiac fat. Only periaortic fat dissection is provided in detail.

    Thanks for your generous help!


  • Sahithi Chipati added an answer in BIM:
    Is BIM a mandatory attribute for IPD ?

    It is all evident and clear that BIM helps integrate all the required data at different phases of any project, hence it is proving to be very useful in IPD implementation. But, is is a mandatory attribute ? Can the challenges ( legal, organizational and technological ) to implement IPD be overcomed with any other solutions ? If yes, what are they ? If no, why?

    Sahithi Chipati · Deakin University

    Ammar Dhakil, thank you for the answer.Yes BIM is not just a software, in the reasearch that I have been doing, few journals mentioned that BIM is mandatory, where as few potrayed BIM to be extremely helpful but not mandatory..so I was curious as to what would be the alternative if BIM is not in the scenario.

  • Kwamina Ewur Banson added an answer in Bioenergy:
    Does anybody know about the difference between theoretical, conceptual and technical frameworks in PhD level research?

    To study the impact of bioenergy on livelihood of people, there may be some theoritical frameworks. e.g. Sustainable Livelihood Framework (SLF) used by DFID. I am confuse, what's the main difference between above mentioned types of frameworks? and which one of them in my case, is suitable?

    Kwamina Ewur Banson · University of Adelaide

    Theoretical framework
    Theory is a large and complex philosophical and empirical field, with many variants of applicable theory emphasizing different aspects. For example, there are variants of Information Theory; there is the related area of Cybernetics; the Second-Order Cybernetics; and Chaos and Complexity Theory. These may differ depending on your field of study. Theories are by their nature abstract and not content- or topic-specific. Even though various theoretical models of health behaviour, quality of life, or sustainability may reflect the same general ideas, each theory employs a unique vocabulary to articulate the specific factors considered to be important.

    Conceptual framework
    A conceptual framework is an analytical tool with several variations and contexts to be seen in your research. It is used to make conceptual distinctions and organize ideas. Strong conceptual frameworks capture something real and do this in a way that is easy to remember and apply
    The conceptual framework might look something like as attached:

    Technical frameworks
    These are the set of assumptions, concepts, values, and practices that constitute a way of your respondents or experts involved in the research view the issues under discussion including you deductions and how you analyse and conclude your ideas in relation to theories and the framework.

  • Douwe Verkuyl added an answer in Homeopathy:
    Can anyone provide further views on the application of Homeopathy and water memory?

    The principal problem on high dilutions study in Homeopathy is the "water memory effect". Skeptiks says "water memory contradict the all laws of physics, chemistry and biology", this is true? this question is important on the theoretical level for this reasons: Different experimental groups has been demonstrated the long term effects on the context of homeopathic dilutions i.e: 1) Louis Demangeat in blinded experiments demonstrate the macromolecular organization of liquid water by the Nuclear Magnetic Resonance of histamine vs control; 2) Igor Jerman  and coworkers replicated the "Benveniste" experiments in the context of the electrical transfer information using electrical device for copy the molecular information in native water; 3) Recent studies published in Neuroscience leading journal (Elsevier) demonstrate the beneficial effect of the Cocc 30c dilution on the sleep deprived rats, this researchers using a double blind placebo design; 4) Luc Montaigner and coworkers shown the bacterial DNA has capable to emit electromagnetic  radiation, this signals is save and copied and information transfer; 5) A new review published by Robert Hahn, look and scrutinize the four most important meta analysis published in the leading journals, Dr Hahn has been demonstrated the superiority of homeopathy vs placebo; 6) The coherent domains, postulated for the physical basis of homeopathy is reviewed by the female scientist Mae Ho Whan (in Water Journal); 7) Other research in the agrohomeopathy shown the utility of the selected homeopathic dilutions in agriculture; 8) Socio anthropological works shown the general benefit on the human experiences using homeopathic or homeopathy with conventional medicine. 

    I don´t understand: Why skeptical movement refuse the experimental data? is most important the word of an magician (James Randi) or the word of a qualified scientists?

    Douwe Verkuyl · CASA Klinieken, Leiden

    There is only one global science that applies to chemistry, physics, astronomy, biology, quantum mechanics etc. Because there are psychological and cultural differences medicine has local accents. The basic medical science is universal.

  • Petr Tomek added an answer in Xcalibur:
    Is there any freeware alternative to Agilent Chemstation or Masshunter that can handle Agilent files?

    I can't seem to get either of those working on my personal computer. Probably need a license or some connection to the machines. For example, Chemstation will install but I can't view any spectra (UV, MS) and there are some other limitations. Masshunter starts giving me errors once started and I cannot load any file. Agilent sucks, I had no problems running Xcalibur on my personal computer off-work with no license. I wish our lab would have been using Xcalibur :( I heard about OpenChrome, is that any good, any experiences?

    Petr Tomek · University of Auckland

    Thanks Revathi, Im still unsure what does "compatible printer driver" means? I doubt manufacturers offer "Chemstation-compatible" drivers :) Does this work even if you do not have physical printer?

  • Kourtnee Hoitsema asked a question in Colony PCR:
    How can I overcome mutations that are introduced during the cloning step?

    I am trying to express a gene using sf9 cells transfected with pIZT+gene. Before transfection, I transformed E. coli (DH5alpha) with my pIZT+gene, screened for potential positive clones using colony PCR, did a miniprep, then sequenced the minipreped plasmids to find one that is mutation free. I have been using LongAmp taq for all the PCR steps (my gene is 2.2kb). My sequence results show mutations in every single clone (7-12 nucleotides of a 2.2kb gene). Some of the mutations were the same, others were different. I then sequenced my insert to ensure that I wasn't ligating a mutant gene into the vector. The insert (my gene) was relatively free of mutations (there were 3, but they were all silent). These results lead me to believe that the mutations were introduced during the cloning steps, rather that during the PCR. I know the LongAmp Taq is not ideal for cloning work due to its low fidelity, but it doesn't seem to be the problem. 

    Does anyone know how to overcome mutations introduced by the bacterial cloning step? Is there perhaps a strain of E.coli with a high fidelity/proofreading polymerase?

  • Graham Pulford added an answer in Weather Radars:
    Is there any design methodology for aircraft radars?

    I want to know if there is any design methodology for aircraft radar warning ,weather radar or fire control radar.

    Graham Pulford · Thales Group

    A good book is Stimson's Introduction to Airborne Radar. There are a lot of engineering trade-offs to consider and this should give you some idea.