Q&A

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  • What is the latest cutting edge research going on in the field of corporate strategy pertaining to the Supply Chain in particular?

    What is the latest research work in Supply Chain as a learning organization?

  • Eraldo Banovac added an answer in Academic:
    Could you please name necessary steps for developing a more innovative organization?

    Academic knowledge and managerial experience is first built on what others have said, done or written. What are the capabilities organizations must develop
    if they want to grow and compete in innovation-intensive environments. 

    Eraldo Banovac · Croatian Energy Regulatory Agency

    Open-mindedness of management and staff is a signiificant precondition to view the posibilities of developing a more innovative organization.   . 

  • Marcel M. Lambrechts added an answer in Personality:
    Who has got more power: the Gray eminence or the Head?

    Throughout history there have been many high-profile cases of personalities behind the scenes directing power with or without the consent of the person who would have had the charge to exercise it.

    In ancient Rome: Seneca and Nero

    In France: Richelieu / Mazzarino versus their king

    In the US: Eleanor Roosevelt versus Franklin Delano Roosevelt

    In every day's life:

    wife versus husband
    secretary versus head of the department
    assistant professor versus Professor

    And in your life would you prefer to act as  a gray eminence or as a head?

    Is there in the governance of your country a similar problem?

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    Gray eminence may take decisions taking past events into account that are not accessible to the decision-maker/head?

  • What are the disadvantages/limitations of inverse finite element method for soft tissue experiments?

    During working on soft tissue experiments, I need to try inverse finite element characterization and I need to check all disadvantages/limitations of this method.

  • How would you define a "model" within a theoretical research?

    For instance, if you have a particular strategy developed for addressing an education research issue, would you refer to it as a "model" or a "strategy"?

    Anup Kumar Bandyopadhyay · Jadavpur University

    Strategy is A plan of action designed to achieve a long-term or overall aim. A theoretical model on the other hand gives an abstract description of a given system. Depending on the requirement a model may highlight one single aspect of the system and hide the other details. A model normally contains enough formalism such that it is not ambiguous. Because of this property theoretical experiments can be designed to estimate the performance of the system in different environments. Given a good theoretical model I believe the performance of a strategy can also be evaluated.

  • Archana Sinha asked a question in Thermal Imaging:
    How to estimate signal-to-noise ratio of an image?

    This is primarily to compare different thermal images obtained in an experiment.

  • Ian Teo added an answer in Protein Extraction:
    Do you have any experience with protein extraction from nylon membrane?

    I am after a protein extraction from nylon membrane protocol. I would like to identify the protein that caused a 'shift' during an electrophoretic mobility- shift assay (EMSA) by MS? Thanks.

    Ian Teo · Imperial College London

    Electroelution ? Cut out strip put into dialysis bag and electroelute in an appropriate buffer. It depends if you want a whole protein or if fragments  are sufficient for analysis - could try site specific cleavage / digestion?

    This is a very long thread, but halfway down is a discussion about getting proteins of PVDF which may be of some assistance. If not, ignore.

    https://www.abrf.org/archives/email/sel_com/ephor/ep9596.html

  • Assma Azeroual added an answer in Watermarking:
    Any articles in Fragile watermarking for video?

    Hello

    Please do you have some articles in fragile watermarking for videos?

    Thank you very much

    Assma Azeroual · University Ibn Zohr - Agadir

    Thank you very much Mr Mousavi

    A hybrid scheme of robust and fragile watermarking for H.264/AVC video


    A Novel Video Content Authentication Algorithm Combined Semi-fragile Watermarking with Compressive Sensing


    Integrity authentication scheme of color video based on the fragile watermarking


    A fragile watermarking scheme using prediction modes for H.264/AVC content authentication

    A Digital Watermarking Scheme Used for Authentication of Surveillance Video


    H.264/AVC video authentication based video content

  • How do you implement achievement function of’ ‘education’’ in your class?

    For a man to be educated it is insufficient that he should possess skills. He must develop some sorts of conceptual schemes at least in the area in which he is skilled and he must have organized a fair amount of information by means of the ‘‘knack’’. It requires some understanding of principles; of the reason why of things. According to Peters, (1962), when one fails to grasp these underlying principles, it lead the person in question to unintelligent ‘‘rule of the thumb’’ application of rules. That individual is unable to make exceptions on relevant grounds and he becomes bewildered when confronted with novel situations. What are these principles and how do you ensure understanding of them in your class?
    Education, psychology, sociology

    Gordon Ade-ojo · University of Greenwich

    At the risk of sounding like a traditionalist, I refer you to Bloom's taxonomy/ domains of learning. The point to remember is that learning is potentially manifested in three domains of the cognitive, the behavioural and the attitudinal. The cognitive possible captures what some might call knowledge for the want of a more suitable label, the behavioural to skills and the attitudinal to outlooks and perceptions. You will find that there is some form of convergence between these three domains and the three categories you have identified. A good teacher, therefoer, must plan for their learners to learn in these three domains.

  • Ben Jones asked a question in DMSO:
    Can I use freeze dryer to remove DMSO?

    I want to use an IP3R inhibitor (xerospongin C) in an in vitro calcium release assay with CHO-K1 cells. I accidentally dissolved the small amount we received in DMSO at a concentration which means the cells will be exposed to 2% DMSO when added at the standard concentration this compound is used. It might be OK but I'd prefer to avoid it. 

    We use a freeze dryer in the lab to lyophilise peptides in water. Can I use this to remove the DMSO, then resuspend to make a more concentrated stock to use in my experiment? 

    The volume needing to be removed is ~200uL.

    I've seen a few comments suggesting variously that DMSO can & can't be removed by lyophilisation. If anyone can tell me if in my circumstances it should be possible, I'd be very grateful (and if I need to do anything extra, e.g. add a bit of water first).

    Thanks!

  • Is multiple valued logic as it pertains to digital computers a viable alternative to binary logic?

    Computer scientists, computer engineers, applied mathematicians, and physicists are familiar with options in which there are no middle choices between true and false. Statisticians are familiar with the soft logic of probability, and physicists are familiar with the logic of uncertainty. The lack of such choices is inconvenient and critical when trying to determine whether the status of a computer system is go, wait, or no-go. Multiple-valued logic is concerned with these intermediate choices. The major drawback to overcomplicated flowcharts dchecked, corrected, or modified. This situation suggests a structured design approach, where a structured flowchart or well designed program is built up to an adequate level of detail according to definite rules from a small, simple, and sufficient set of elemental blocks or primitives. Developments in multiple-valued logic as related to computer science include a range of disciplines in which comparisons to multiple-valued logic and computer science are being made, such as neural science and ethology.

    Bernard Desroches · University of Lyon

    As for philosophical logic and logical philosophy, the question leads to Jan Lukaciewicz's work on Aristoteles' non-contradiction principle. Very lately translated in French (only in 2000, though it was published in 1910 in Poland... and I do not know when for the english version).

    "There is no logical or ontological reason for accepting the non-contradiction principle, but a reason which concerns human nature itself". (op. cit. p.27)

    Best regards

    B. P. J. Desroches

  • Ishag Adam added an answer in Middle East:
    Is there a proven relationship between the spread of infection and the method of personal cleansing after toileting?

    This question arose while designing healthcare facilities in the Middle East, but the question is applicable in many regions. In some countries it seems common to use a spray wand (a.k.a. ablution hose or health faucet) after toileting. This seems to me that the water spray could cause increased growth and spreading of pathogens. However, I have not found much objective evidence on the issue.

    Other methods of washing are toilet paper, free-standing bidets, and integrated spray jets in the toilet seat. The preferred method appears to be culturally driven.

    Ishag Adam · University of Khartoum

    Dear  Senthilvel Vasudevan

    It is amazing

  • Any Algorithm/Technique for increasing the energy efficient for Sensor Nodes in Wireless Sensor Network.... ???

    I want to increase energy efficiency for sensors nodes which present in Wireless Sensor Network. These sensor nodes sends/forwards information to mobile sink when it is near to that cluster. Entire information passes through only Cluster Head after that cluster head forwards the information through Rendezvous Node. So here I want to increase network life time.Any Algorithm or technique for increasing life time for WSN.   

    Arjav Bavarva · RK University

    There are many techniques and protocols and algorithms which increase the lifetime of the network. Make your domain narrow further. On which layer you want to work. Using mimo technique (physical layer) you can increare life time of the network. Mac layer protocols like smac, tmac etc does the same. Using retransmission policy and proper congestion window size may helpful to increase the lifetime. I want to suggest one good paper in this domain. Just type on google- data aggregation in wsn. You will get one paper related to that. I dont remember the exact title.

  • Has anyone added clarified egg yolk to canine semen?
    Does anyone use clarified egg yolk (centrifuged with re-destilled water) in a Tris canine semen extender? I am wondering if the added volume of this CEY is same as in case of whole egg yolk (20%)? We are preparing our experiment for extender comparison and we would like to use CEY prepared according to the protocol for Eland epididymal sperm freezing in a Tris extender.
    Ondrej Simonik · Czech University of Life Sciences Prague

    Dear Omer,

    thank you kindly for answer. I agree with you, that volume of CEY and EY is no the SAME thing. However, we have performed some experiments with this and different possibilities, now it is in evaluation phase.

    Thank you.

    My best regards,

    Ondrej

  • What are space and time?


    Space and time are widely used concepts or categories. They play a major role and are critically discussed in physics, natural science in general and in philosophy. A quote of Kant is: "Space and time are the framework within which the mind is constrained to construct its experience of reality.”. But in Einsteins approach space-time is an attitude of the reality. In cosmology space and time began after the big bang. But for MacTggert time was unreal.
    There is no doubt that space and time are basic concepts especially in modern scientific theories. Theories and sciences like cosmology, geology, theory of evolution and phylogenetics as well as developmental theories in biology or psychology, culture theory and especially history are unthinkable without space and time.
    What do you think?

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    @Valentin: Time: is (or means) a sequence of changes which we compare to other periodical changes which we name clocks. Now the question is - what exactly changes in a "change"? And the answer: one or more attributes of the objects or phenomena which we observe. As we can notice, those attributes always appear, change, or disappear within a region of space. And that's the point where the concept of Space is inevitably linked to the concept of Time.

    OK to me

  • Rauf I Azam added an answer in Academia:
    Do you have experience with caste employment at Universities in spite of the law?
    There are many examples of illegal employment of children of professors. It is an ethical issue. It is about nepotism. Rectors of the University of Novi Pazar, in Serbia, hired several members of their closest family, although there were better candidates for the academic places. Do you have experience with such phenomena?
    Rauf I Azam · PMAS - Arid Agriculture University

    A good question posed by @Ljubomir and valuable comments by several contributors. The problem of nepotism is perhaps more deeply rooted and broadly spread than many of us think. We in Pakistan also face this problem however its dimensions may be different from some other societies. As pointed out by others the construct of this problem connects directly with the construct of a society but it also depends on economics. Lack of opportunities or more importantly the wide variation between the benefits provided by different opportunities provides too much of motivation to socially, politically or economically influential groups to use unfair and even illegitimate means of collaboration, maneuvering or manipulation to grab the desired opportunities. Teaching positions at universities are also subjected to illicit collaborations but strict and high level of academic requirements filter out a lot of such influence while some other positions where meeting basic qualifications is easier are more prone to manipulation.

  • Tang Suye added an answer in Thermodynamics:
    Why the equation of the first law contains a negative definite function?

    For the first law

    dU=TdS-pdV+ΣμdN.

    According to the physical meaning of the internal energy, U represents the total energy within the system, so should be expressed as the sum of the different types of energy within the system, whereas, if we consider an integral equation, for Euler equation

    U=TS-pV+ΣμN.

    Since p and V are the two positive definite variables, so –pV is a negative definite function. Therefore that, the mathematical form of Euler equation conflict with the physical meaning of the internal energy.

    For instance, for a photon gas, the integral of –pdV is less than zero. Helmholtz free energy

    F=-pV=-U/3.

    Where F is a negative definite function, so F cannot be explained as a part of the internal energy, then what it is?

    I have my own answer for this question, but want to know what your opinion is.

    Tang Suye · Independent Researcher

    Dear John,

    Yes, we both know this, and this is the difference between you and me. In fact, if you note carefully, you can find in many thermodynamic textbook (physics or general physics), for an ideal gas, the equation of the internal energy is expressed as,

    dU=TdS-PdV

    This is a classical equation.

  • Alexandre Léglise added an answer in Startups:
    Is anyone interested in an innovative marketplace for biological samples?

    For more information check our webpage: https://biosample.squarespace.com 

    Any feedback is welcome!

    BioSample, a Startup Weekend Brest 2015 project.
    http://brest.startupweekend.org

    Alexandre Léglise · Cell&Co Biorepository

    Hello Raquel,

    Thank you for your comment.

    This is a Startup Weekend contest project. The page was built yesterday to check the market need. You are only on Twitter yet.

  • Abdullah Al Tarique added an answer in ELISPOT:
    Can I use a portion of the ELISpot plate and save the rest for later assays?

    I have an Elispot to do but only 30 wells for this experiment so can I use a portion of the ELISpot plate and save the rest for later assays (within a month) ? Thanks

  • Does accelerated charge emit photons to all observers?

    We know that a decelerated charge emits photons. So you can visualize an observer in a stationary frame of reference that detects these photons.

    However for another observer in an accelerated frame of reference that is moving, at the same pace as the charge, the charge appears stationary and apparently should not emit photons.

    How do we reconcile these two apparently contradictory positions?

    Daniel Baldomir · University of Santiago de Compostela

    Dear Dereck,

    When you add two links it seems that this question is unsolved or with any difficulty to understand it. Let me to tell you that this is non true at all.

    The main idea of electromagnetic radiation is very simple: if we make to depend the trajectory of the charged particle of the past time (curiously it could be also of the future time or non causal time as Feynman and Wheeler studied) and keeping in mind that from the retarded time to actual time the velocity of light is constant c ( Lienard and Wiechert make this work in a context out of relativity and previous to it). Then you obtain the Lienard-Wiechert potentials that you need more than to apply them tha usual Maxwell equations for obtaining the electromagnetic radiation.

    As you can see here is not necessary at all to say what is the observer once the trajectory of the retarded time is assumed and this is the only part you need to take for the discussion. If you could chose one observer which could see the retarded time coinciding with the actual time (say to be the same and in one only instant) then no radiation could exist for it, but this is impossible in reasonable situations.

    David J. Griffiths, Introduction to Electrodynamics, Prentice Hall, 1999

    D.Baldomir and P.Hammond, Geometry of Electromagnetic Systems, Clarendon Press, 1996

  • Gordon Ade-ojo added an answer in Atlas.ti:
    Qualitative research tools like ATLAS.ti, Nvivo etc. have appeared and more are likely to appear. How good are these tools?

    Despite its popularity increasing, the analysis of qualitative data is cumbersome. Coding, theme development etc. manually consumes lot of time though quite a number of researchers are still using manual methods.  New tools are being developed and the existing ones are getting updated but its diffusion among the researchers are low. Lot of training and practicing is needed before researchers become conversant with these.

    Gordon Ade-ojo · University of Greenwich

    Not necessarily. I'd say , however, that we are being invited to become one in conceptualisation

  • Ilya V Kublanov added an answer in Bacteria:
    How do I distinguish and determine species from potentially two different bacteria if their basic morphological features look the same?

    For example, two different species of coccus in mixed culture. How would I be able to determine their respective names?

    Ilya V Kublanov · Winogradsky Institute Of Microbiology

    DGGE or clones libraries. 16S sequencing after separation of bands or clones, respectively.

  • Is participatory observation as a research method possible in public bureaucratic organizations?

    Participatory (collaborative) research as an effective research mehod is known from Brasilian researcher Freire's times. among marginal groups. Do You think such kind of research is possible in a given public bureaucratic organization?

    Gordon Ade-ojo · University of Greenwich

    Of course, it is possible. Two issues to be aware of though: First is access. Would you be able to access the setting? Second is bias. Would you be able to sustain your neutrality and avoid bias. That is usually one of the difficult issues associated with participatory research and which sets it apart from ethnographic observation

  • Nezisian Soltani added an answer in Abaqus:
    How can I prevent this problem in converging in explicit analysis in abaqus?

    I have a 2D model in abaqus (Explicit) and analysis is quasi-static (with time 50). Material model is damage plasticity. I can see some crack in my model. But when I refine mesh, displacement will be very large and show no converging in solving.

    Please help me on how I can solve this problem.

    Nezisian Soltani · Tarbiat Modares University

    I understand that the kinetic energy in my model is very large (e6) and cause the wrong result. I use of longer time in my model and I  reform the mass scaling in step module but it could not  help me. please help me. I am working on this problem 3 weeks.

  • Maurizio Iocco asked a question in Neurological:
    Have you ever seen in peripheral traumatic nerve injury a neurological repair without functional recovery?

    I'm sure that in a few cases we have seen patient with persistent loss of function after a peripheral traumatic nerve lesion, but their conduction was normal.

    Have you too?

    Do you know why?

  • Is there a Dirac equation for the Proton or Neutron?

    To the best of my knowledge, because the Dirac equation explains very well the gyromagnetic ratio of the Electron, it is typically considered to be an equation for the Electron. There seems to be no such thing as the Dirac equation for the Proton or Neutron despite them being spin-1/2 particles. After the calculation that I conducted in the present paper, I would like to believe that the Dirac equation can be thought of as an equation for any general spin-1/2 particle. I certainly will be happy to hear your thoughts on this very important matter.

    Mohamed El Naschie · Alexandria University Alexanderia Egypt

    question need to be a lettel more accurate

  • Serag Eldin El behairi added an answer in Freezing:
    Protocol for freezing adherent HEK293T clones in an 96 well plate?

    I'm trying to examine several hundred clones and will need to freeze some in the 96 well format. I was wondering If there is any recommended protocol that results in reasonable viability on revival? Thanks!

    Dr  Pietro Pilo Boyl  is good but I have tow notes:

    The first : The freezing medium must be  50% Fetal bovine serum, 7% DMSO and 43% Medium (2X)  ( Not 80% FCS and 20% DMSO)

    the second: You must sealed your plate after adding the freezing medium using plate sealer  

    GOOD LUCK

  • Nirmala Menikpura added an answer in Waste:
    Has anyone examined the emission factors for open burning of household waste in case of a rural dumpsite ?

    Are there any working papers, reports , projects which assess these emissions for an illegal waste disposal site using IPCC 2006 guide and/ or experimental data ?

    Nirmala Menikpura · Institute for Global Environmental Strategies

    CCAC initiative is doing some research/pilot scale project on Black Carbon, Organic Carbon emissions from open burning. here is one of the ppt file. please check CCAC website for more information.

    https://www.globalmethane.org/expo-docs/canada13/msw_03_Damodaran_MSW.pdf

  • Is it possible to take representative samples of soil microbial communities for large (>1m2) spatial scales?

    Microbial community distributions are reported to be extremely patchy (even within a kg of soil).  Are there spatial scales (1m? 1km?) for which taking a representative sample would be untenable logistically?

    Tymur Bedernichek · National Academy of Sciences of Ukraine

    Dear Dr. Vorenhout,
    That was just an example. No matter 10 x 10 mm or 10 x 10 m – such an approach gives the researcher an opportunity to find some scale-depended properties of soil, forest, community etc. You are absolutely right that 10 cm might be a long distance for microbes. However, as far as I understood the question of Dr. Heath W Garris, the problem was to describe microbial community of large territories. Therefore, a high level of generalization is needed.