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  • Jörg Erdsack added an answer in Alternative Energy:
    How detailed does an AHP hierarchy need to be?


    I was asking myself the above question when structuring a hierarchy to find out where businesses in the industry like to invest in optimization measures.

    The hierarchy is attached.

    The five alternatives are: Energy efficiency, optimization measures for processes, quality, technology and supply chain.

    Now I would be able to break down the criteria especially the quantitative ones into additional sub-criteria. For Example: Net present value in 0.15 - 0.3%, 0.3 – 0.5%, 0.6 - 1%, 1 - 2.8%, 2.8 - 5%, > 5% or payback period in static and dynamic and then in years (e.g. 0 - 1.5 years, 2 years etc.).

    But is that really necessary?

    Thanks in advance for any help you can provide. I also appreciate any comment regarding the hierarchy.

    In his paper "How to make a decision: The Analytic Hierarchy Process" (1990), TL Saaty gave an overview on how to structure a decision problem.

  • Marc Tessera 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.


    "The word ''conscious'' and ''unconscious'' in the familiar language where they have been invented refer to our awareness , it simply been we are aware or not.  These are words whose meaning belong to our life world, our phenomenal world".

    As you know I find quite unclear the adjective "phenomenal" and surely not apropriate to the scientific investigation.

    Anyway, ‘‘Conscious’’ is an ambiguous word but I agree with Dehaene and Changeux when they say that "in its intransitive use (e.g., 'the patient was still conscious'), it refers to the state of consciousness, also called wakefulness or vigilance, which is thought to vary almost continuously from coma and slow-wave sleep to full vigilance. In its transitive use (e.g., ‘I was not conscious of the red light’), it refers to conscious access to and/or conscious processing of a specific piece of information".

    I think both aspects can be the scope of the scientific investigation.

    Regarding the latter meaning of consciousness I agree with these authors that "at any given moment, only a limited amount of information is consciously accessed and defines the current conscious content, which is reportable verbally or by an intended gesture" and that "at the same time, many other processing streams co-occur but remain nonconscious".

  • Pablo Duran-Perez added an answer in Strabismus:
    What is the management for teenager sufferring recent onset transient concomitant exotropia ?

    What is the management for teenager sufferring recent onset transient concomitant exotropia ?

    14  y.o. girl's parents revealed  2 yeras ago strabismus in her dauther- transient alternating exodeviation dominantly in her left eye, more prominent when girl is tired.

    VA 1.0

    Concomitant strabismius 10-15 degree . Anterior and posterior without abnormality. The girl has headaches without localization Neurologist reject any pathology.

    What is your opinion ?

    Pablo Duran-Perez · Instituto Oftalmológico Gómez-Ulla

    As has been suggested before, I would check the girl for any refractive errors (manual retinoscopy undel cicloplegy is the gold standard in children and teenagers) and do a convergence test. It is very likely that although VA is 1.0 in both eyes a small myopia is found.

    Concomitant, intermitent exodeviation is quite common and usually associated to convergence insufficiency. That would explain the headaches as well. In that case, glasses and convergence exercices can help. If they don't, surgery is usually needed to alleviate the symptoms.

  • What is the best intraoperative management of a 75-year-old male with 3 vessel CAD, intramyocardial LAD, heavily calcified (egg shell) aorta?

    revascularisation options in egg shell aorta

    David Nespor · Centrum kardiovaskulární a transplantační chirurgie

    I didn' t know about poor EF. In this case just try BIMA (or combination with RA) revascularization and if the patient will be hemodynamically unstable, just perform LIMA-LAD with hybrid approach - stenting of other vessels. In the case of urgent necessity of ECC, how is it with atherosclerosis of subclavian or axillary artery? You can try axillary artery cannulation (direct or via 8mm vascular prothesis) and do the operation on pump without crossclamping. Moreover, in the case of severe peri- or postoperative hemodynamic instability you can use this vascular prothesis for IABC.

  • Which is a suitable software for large polymer-protein docking calculations?

    Hello everyone,

    I have a problem regarding the performance of a docking calculation between a large polymer and a protein. The polymer is really huge.

    I have tried vina and autodock, but the polymer has more than 32 rotable bonds. Additionally I have tried other softwares like Rosetta or HEX, but with not succes, because are prepared for small molecules.

    Any advice or possible solution?

    Thanks in advance,

    Best regards,

    Melchor Sanchez-Martinez · Mind the Byte, S.L.

    Thanks for your answers.

    SwissDock seems that is not working, due to size problems, as with other software tools.

    On the other side, I don't know hot to download Gold. Can you help me with that?

    Bioluminate maybe is an option but I can only obtain a trial version right? I prefer something more "stable working".


  • Sunish K Sugunan added an answer in Particle Size:
    Can we name a particle of the size 50 nm (obtained from TEM) as a nanoparticle?

    The particle looks bamboo leaf flakes.

    Sunish K Sugunan · Durham University

    Thank you!

  • Do you think that a quantum computer will be just an addition to a traditional computer?

    Or will it be a separate device?

    Jean-Luc Paillet · French National Centre for Scientific Research

    I think that, from a pure computational mathematics point of view, Quantum Computers could provide a set of functions  f:N --> N greater than the set of general recursive functions obtained by classical Türing Machine. For example, QC should be able to produce true random sequences of integers.

  • Can new rifts start in the interior of oceanic plates?

    Does anyone knows a case of a rift that started in the interior of an oceanic plate, far from the plate boundaries ( thus excluding backarc basins)? Would that be mechanically possible?

    Joao C. Duarte · Monash University (Australia)

    Many thanks Ramadan! I agree that that is the way to go..

  • Robert H. Eibl added an answer in Nucleolus:
    Does anyone know why a cell can lose its nucleolus?

    I work with MCF-7 cells and, after a treatment, they appear to have no nucleolus. Does anyone know why this is happening? Thanks!

    Robert H. Eibl · Universität Heidelberg

    So, are they just close to death. Are the surviving cells really also "without" nucleolus? - Anyway, sounds interesting and interesting to elucidate. Good luck!

  • How to know about annealing temperature of primer?

    If the Tm value for forward primer is 29.2 and for reverse primer is 46.7 ... what will be the annealing temperature for PCR in such situation.?? Can anybody suggest please...

  • Mahdiyar Sarayloo asked a question in CDMA:
    What parameter measure the robustness of system like CDMA against the attack?

    Hi everyone

    Consider that we have a communication system using spreading sequence, what parameter(s) does measure the robustness of system against the attack on the spreading codes?

  • Are there applications for corticosteroid injections in joints in case of cartilage degeneration?

    I'm looking for several different studies and their results to see if there's any improvement in therapy. I want to know more about application in the knee joint.

    Thank you!

    Adriano Marques de Almeida · University of São Paulo

    Patients with arthrtis and synovitis, with effusion and hiperthermia, in whom you have discarded the possibility of joint infection, answer dramatically to intraarticular corticosteroid injection. It also may be combined to hyaluronic acid, accordingly to the paper below.

    Adding Triamcinolone Improves Viscosupplementation:
    A Randomized Clinical Trial. Clin Orthop Relat Res (2013) 471:613–620

  • Hamza RAHAB asked a question in Buffer:
    What is the cause of having a low values by spectrophotometrer when testing buterylcholinesterase?

    We started a  protocole to study the anti-cholinesterase activity of some plantes. After dilution of 0.2 mg in 1 ml of a Ph 8 buffer and further dilute 300 microliter in 2 ml as indicated in the protocole we got an absorption value very low (0.08) when the expected value in the protocole is 0.4-0.5.

    would you give me the detailed protocolme you use in your laboratory?

  • How do I calculate fano factor?

    Hi! I have datasets of irregular spiking of neurons. I have calculated ISI of each spike train, and have computed the fano factor for each spike train as std(isi)^(2)/mean(isi). The values I get are way to high (~100), and for this type of neuron ought to be ~0.2.

    Any suggestions about what I might be doing wrong?

    Oscar Villalon · University of Miami

    WOW, if I'm understanding correctly, these are time units, so u should really not be getting those numbers. A few things I can think of:

    - Check that ur ISI is not including the time before or after the actual spike train. It's easy to make that kind of mistake if u're dealing with a lot of indexes in your program.
    - Go to ur recording of a couple of individual spike trains and look at the intervals. If these are different enough, u may need to separate the spike trains. U may be including more than one spike train each time.

    Let me know how it goes...

  • Joseph B Moore IV added an answer in iPSC:
    Is there any iPS kit or OSKM-containing MEFs inducible by DOX?

    I'm going to analyze the effect of a couple of genes/agents on the efficiency of iPSC generation. To save time, I am looking for any reliable iPS kit or OSKM-containing MEFs inducible by adding DOX or something like that, so that I can assess the effect of my agents on the reprogramming process.

    Your comments are appreciated.


    Joseph B Moore IV · University of Louisville


    Check out the link below . . . they have some inducible systems.




  • During silver staining I am unable to stain the gel - it remains blank as if it were freshly cast. How can I overcome this problem?
    I have isolated a protein from cell lines and I want to confirm the presence of the protein by Bradford reagent. But when trying to silver stain, I am unable to stain the gel - it remains blank like it was freshly cast. I have followed the standard protocol of 0.02% Sodium thiosulfate for one min 0.2% silver nitrate. I used a standard developer and a fixative. When discarding the reagents, the colour of the waste turns a black/brown colour. How can I overcome this problem?
  • Ghanim Al-Khaledi added an answer in Synapses:
    Does anybody know if there are any studies about spinal cord lesion and exercise effect on callosal-corticospinal synapses or axon remodelling?

    I'm looking for information about callosal-corticospinal connections in mouse motor and sensory cortical areas and if there are any works about a possible modification, in terms of axons or synapses, after spinal cord lesion and subsequent exercise. I'm also not sure about the percentage of callosal motor and sensory fibers representation in mouse and at which extent their are connected with corticospinal neurons and what is the functional meaning of that.

    Ghanim Al-Khaledi · Kuwait University


     a good place to start. http://onlinelibrary.wiley.com/doi/10.1111/nyas.12052/epdf

    and http://www.rehab.research.va.gov/JOUR/08/45/2/pdf/Lynskey.pdf  hope you find them useful.

  • Abdul Basit added an answer in Pro-E:
    How can i model the indentation process in Pro e?

    i have to model the vicker indentation process how can i model it?

    Abdul Basit · Hitec University

    Hi Shivraj actually i have to simulate the crack propagation process for which i use an indentation technique to make an indent on the material. it means i have to apply different force to make an indent in the material and by increasing force depth of indentation also increases. now how can i create this model on proe? suppose i made a specimen geometry now i want the simulation that when i apply force as depth increase it will simulate and show stress etc............. i hope you will understand.

    waiting for you reply


  • Ibraheem Hamdan asked a question in Sodium Chloride:
    Whats the optimal dilution percentage of the sodium chlorid to use it as a Tracer?

    whats the optimal dilution percentage for the Sodium Chloride with water to use it and inject it in the ground as a Tracer?

  • Ariel Linden added an answer in Regression Analysis:
    Is it justified to combine (e.g. sum) several potential predictors into one predictor for regression analysis?

    For example, consider logistic regression where the binary outcome is presence or absence of a certain disease, and there are many potential predictors. Each predictor is a small piece (a "bin") of the NMR spectrum for an analyzed body fluid (e.g. urine). When all predictors are used for the regression, several of them approach statistical significance (e.g. p values of 0.06-0.1 and 95% CIs for the OR slightly overlapping with 1). But if the values of these borderline predictors are summed, combining them into one predictor, then the p value decreases and OR CIs no longer overlap with 1. Is this justified?

    Ariel Linden · University of Michigan

    Hi Igor,

    Thanks for the clarification. I am not sure that summing the values together is entirely appropriate here since they may not be related. One simple thing to do is look at the correlation/covariance matrix of all those covariates that you are calling "bins". That will give some indication of how they relate to each other. Perhaps those with high correlations make intuitive sense to you (based on your content expertise). This may guide you in your consideration of how to consolidate (or not) those covariates.


  • Zohara Nafeesa added an answer in Molecular Weight:
    How do I measure the molecular weight of high molecular weight glycoprotein?

    Hello Every one

    My purified (single peak in HPLC) sample is glycoprotein (3.5 microgram/100 microgram ) with molecular weight range between 60-80 kDa using SDS PAGE. I had given my sample two times in separate places for MALDI-TOF using sinnapinic acid as matrix but they told it is not ionizing.Please suggest me how to know Molecular weight of this glycoprotein.

    Zohara Nafeesa · sri jaychamarajendra college of engeenering mysore

    Thanks a lot for your valuable suggestion.

  • What are the disadvantages in fabrication of bioinspired scaffolds for vascular tissue engineering application?

    Bioinspired Materials, vascular tissue engg, Fabrication,  

    Julio César Sánchez Pech · Centro de Investigación Científica de Yucatán

    Hi Suresh, I think you refer to scaffolds made of collagen, gelatin etc. If so, the principal disadvantage is the source of this biomaterials, because there is a variation of species which can proceed, for example, the collagen can be from diferent mouses. This may affect the response of the cells, with respect to the scaffold.

  • Frank A. Ocaña asked a question in Sampling Design:
    Which is the best analysis strategy to determine the relative contribution to variability in abundance of certain benthic species?

    I surveyed 4 sites (A, B, C and D) during six times along a year. On each site I measured abundance in six sampling transects.  I have a total of 36 sampling units on each site.

    Sites A and B are very impacted and sites C and D are reference with almost no human disturbance but topography is different A=C ≠ B=D (i.e. A and C present steep slope; B and D present gentle slope). I have 3 factors: Time (6 levels); Impact (2 levels) and Topography (2 levels). Data found to be normal and homocedastic. I´m interested in determining the relative contribution of Human disturbance and Topography to abundance variation of this species.

    Is it possible lumping data together in order to perform two ANOVAS to determine the effect size attributed to each factor and then compare them?

    I mean to perform a bifactorial ANOVA grouping data to compare Impact versus Reference sites and to calculate the effect size with its confidence intervals. To perform another bifactorial ANOVA grouping data to compare Gentle slope versus Steep slope and to calculate the effect size with its confidence intervals. Then comparing the effect size for each analysis in order to determine the relative contribution to variation of each factor

    Note that: 1) variation due to time should be the same for both ANOVA; 2) in the first ANOVA the two sites on each level present different topography; 3) in the second ANOVA the two sites on each level present different disturbance.

    • If it’s not possible to do that, there is any other alternative to determine relative contribution of Impact and Topography to variations in abundance with this sampling design?
  • What is the difference between racism and ethnic discrimination?

    Before answering my question. Kindly read my explanation first.

    Base from two books i read, i conclude that:

    There is no difference between those terms. Ethnic Discrimination is the synonym of Racism.

    Below are my explanations and sources:

    From a book titled "Race and Ethnic relations" published in 2012 by Merger 

    The term Race is hardly use in the research field nowadays. Researchers prefer to use Ethnicity instead. Hence there is no difference between Race and Ethnicity

    In the past, there are difference between and race and ethnicity. Expert usually based different race by the difference of phenotype such as skin color, hair color or shape of the nose. While ethnicity is more into social and cultural category, for example certain kind groups who has the same behaviour consider to have their own ethnicity.

    Later , confusion start to develop to draw fine distinction between race and ethnicity. Below are the paragraph i quoted from the book.

    “As Biologist Daniel Blackburn (2000) as explained, all of the popularly used physical features to define races show gradients of distribution within population groups within which sharp distinction cannot be draws. Despite obvious physical difference between people from different geographic areas, most human genetic variations occurs within population. Michael Bamshad and Steve Olson have explained “individual from different population are, on average, just slightly more different from one another that are individuals from the same population.”

    In the last part of the section the author of the book find a subtle way to settle these confusion.

    “Because of its confusing usage and its questionable scientific validity, many sociologist and anthropologist have dispensed entirely the term race and instead prefer ethnic group.” 

    From a book titled "Racism and Ethnic Discrimination" published in 2011 by Lentin page 84

    "Racism becomes a catch-all phrase that can be used to describe almost any situation. It is used to refer any situation of discrimination or unfairness"

    That is all my explanation and sources. I assumed that these terms are the same and the confusion between the two is because maybe some researches still use the old definition and do not follow the update of this topic.

    i am asking this because i am doing my research on this topic and need feedback from other people. You are welcome to contradict my explanation. i would love to read it. However, please write the sources that you are using as the base of your statement.

    Thank you and have a nice day.

    Aleksandar Boskovic · Institute of Social Sciences

    In short, I could also say that there is no difference, as Charles MacDonald did.

    I notice that most of the commentators who claim that there is difference (because race is -- as popular anthropological discourse goes -- meaningless; and ethnicity is somehow "factual") come from the US, but that they have not done research (or at least make no reference to examples) outside the US. People who have been victims of ethnic discrimination can describe their experiences in terms very similar to what we ordinarily describe as racism.

    On the other hand, Pamela Ballinger, when writing about Istria, shows how different ethnic groups in the region used racial stereotypes to refer to "others". Similarly, I note in my paper "Balkan Ghosts Revisited: Racism, Serbian Style" (Anthropos, 2006 -- you can download it on Research Gate) that there is a striking similarity between these two types of discrimination.

  • Does anyone know the lowest amount of sample necessary to obtain reliable enthalpy of solid state reactions from a Setaram C80 scanning calorimeter?

    I will measure powder samples and I would like to determine the reaction enthalpy of solid-solid state and solid-gas state reactions. According to the instrument specifications: "with a three-dimensional transducer the sensitivity of the C80 is independent of:
    - The weight, form and nature (powder, fiber, liquid, etc.) of the sample.

    Does anyone have experience if 10-100mg of sample is enough to get good data (for an enthalpy change in the range of 1-100kJ/mol)?

  • Nader Aghakhani asked a question in Social Support:
    How social support can be used for quality of life promotion in hemodialysis patients?

    Social support is essential for patients with chronic diseases. Is it useful for quality of life promotion for hemodialyss patients?

    If yes, How it can be used?

  • Does a gravitation wave change propagation direction passing near a massive gravitation center (star)?

    As we know light wave passing near a gravitation center (star) changes its propagation direction. Is this true for a gravitation wave? 

    Minas K. Balyan · Yerevan State University

     Hi Robert,

    If the energy is not detectable, it can moves (travel) by the velocity grater than the velocity c of light in vacuum.

  • Saleemulla Mahammad asked a question in Transcription:
    Is there a method/drug to enhance transcription of RUNX1 protein?

    I am studying AML and wondering if anyone knows a method or drug to enhance the transcription of RUNX1 protein.

    Thank you.

  • What does Loschmidt's paradox tell us about the second law of thermodynamics?

    Also known as the reversibility paradox, this is an objection to the effect that it should not be possible to derive an irreversible process from time-symmetric dynamics, or that there is an apparently conflict between the temporally symmetric character of fundamental physics and the temporal asymmetry of the second law.

    It has sometimes been held in response to the problem that the second law is somehow "subjective" (L. Maccone) or that entropy has an "anthropomorphic" character. I quote from an older paper by E.T. Jaynes,


    "After the above insistence that any demonstration of the second law must involve the entropy as measured experimentally, it may come as a shock to realize that, nevertheless, thermodynamics knows no such notion as the "entropy of a physical system." Thermodynamics does have the notion of the entropy of a thermodynamic system; but a given physical system corresponds to many thermodynamic systems" (p. 397). 

    The idea here is that there is no way to take account of every possible degree of freedom of a physical system within thermodynamics, and that measures of entropy depend on the relevancy of particular degrees of freedom in particular studies or projects. 

    Does Loschmidt's paradox tell us something of importance about the second law? What is the crucial difference between a "physical system" and a "thermodynamic system?" Does this distinction cast light on the relationship between thermodynamics and measurements of quantum systems?  

    Sofia D. Wechsler · Technion - Israel Institute of Technology

    Dear H.G,

    If there is similarity between decoherence and increase of entropy is a complicated issue and maybe the people have difficulty in giving an answer. But let me tell you a major dissimilarity between the systems discussed by Loschmidt's paradox and those that undergo decoherence: Loschmidt made his judgements on ISOLATED systems. To the contrary, decoherence occurs on highly NON-isolated systems, e.g. a quantum system in contact with a classical apparatus. That apparatus contains a lot of wires, all sort of peripherals, and there is no possibility to isolate it from the environment.

  • Louis Brassard added an answer in Consciousness:
    Can consciousness be defined?
    Dan Dennett tries to shake our confidence that we ever can know what consciousness is. Would you agree with him?

    Thanks Claudio for Varela's paper.



    When I speak of the contents of consciousness, and I say that I can see a glass, a friend's face, or the sky, I do not suddenly start to speak of neuronal circuitry which picks up information from the world and makes it a correlate of consciousness. Instead I am speaking of something which is necessarily de-centered [excentré], which is not in the brain, but in the cycle, between the external and the internal, which only exists within action and within the cycle, in the same way in which the sensation of existence lives in the cycle between the neuronal apparatus and the body.
    But there is also a third dimension, valid above all for man and the superior primates: the fact of being structurally conceived for having relations with others, with individuals of the same species, of having an innate ability which is empathy, putting oneself in another's place, identifying oneself with the other. The relationship between the mother and child is nothing but a case of empathy. I am unable to separate--not only in infancy, but for the rest of my existence--the mental life, the life of consciousness, the life of language or the life mediated by language, the whole cycle of the socially mediated empathic interaction, from that which I call consciousness. And so again all this does not happen within my head, but in a decentered [excentré] way within the cycle.''