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  • Sabino Maggi 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?
    Sabino Maggi · National Research Council


    nepotism in universities and public research organizations is very common in Italy too. Scandals surface nearly daily but italian society is very lax about these ethical issues.

    A very good account can be found in this news article Nepotism alive and kicking in Italy (http://www.bbc.com/news/magazine-21507168) and in the referenced paper Academic Dynasties: Decentralization and Familism in the Italian Academia (https://ideas.repec.org/p/nbr/nberwo/17572.html).

    I agree with Abderrahmane Kadri and others, it is not a question of being a developed or an underdeveloped country, rather a question of the society which is behind the academic world. When the society is corrupt or does not sense corruption as an important ethical issue, also academia will mirror the behaviour of the society in which it is immersed.

  • Lukasz Zadrozny added an answer in Bone Grafting:
    What is your protocol for when an indispensible instrument or 'bone graft' falls onto non sterile area?

    Patient may be unconscious, sedated or fully conscious.

    Lukasz Zadrozny · Medical University of Warsaw

    With bone graft You will be in trouble, in my opinion there is no method which allows You to sterilize the bone graft especially during the surgery. And with instruments You can always use similar one instead or even try 5 minutes autoclave program to sterilize it.

  • Steingrimur Stefansson added an answer in Chitin:
    How do you elute Chitin-bind protein form chitin resin?


    Steingrimur Stefansson · HeMemics Biotechnologies Inc

    Hi Tengfei, have you tried organic solvents, like 10-25% DMSO or isopropanol?

  • Chang-Er Chen added an answer in Metabolites:
    Which LC-MS/MS is better for metabolomics: LTQ Orbitrap Velos or LCMSMS-3200 Qtrap?


    I'd like to profile and compare a number of metabolities between cell types.

    As I am new to LC-MS/MS, please kindly advice which below instrument would be more useful:

    • LTQ Orbitrap Velos
    • LCMSMS-3200 Qtrap

    Is it that a LC-MS/MS firstly performs untargeted profiling of all metabolites, then a 2nd round of MRM for selected metabolites? Could this be performed in a single instrument (e.g. the ones above)?

    In that regard,

    • Would a lot of starting materials needed?
    • Why would a 2nd round of MRM needed, if the metabolities of interest could be profiled in the 1st untargeted run?

    Thank you very much

    Chang-Er Chen · Lancaster University

    targeted Quantification, then go to Qtrap.

    untargeted identification, then go to LTQ.

  • Louis Brassard added an answer in Computer Science:
    What happened with “The Fifth Generation Computer Systems project (FGCS)”?
    Back in 1982, Japan's Ministry of International Trade and Industry, begun the project “The Fifth Generation Computer Systems project”. The idea was to find the new architecture of computer, i.e. NON Von Neumann architecture, with Sequential Inference Machine Programming Operating System (SIMPOS) operating system is released. SIMPOS is programmed in Kernel Language 0 (KL0), a concurrent Prolog-variant with object oriented extensions. Similar project was in US, the results were various Lisp machine companies and of course, Thinking Machines.

    I’m interested what happened with Japanese “Prolog machine”? Does anyone know something about that?


    As most people in that field I was just naively following the so called guru and like them thought that to succeed we just need a technical solution a kind of hacking mentallity.  And as all naive people who do not know the human history of thought you are doomed to repeat the errors of the past.  Luckily I had some solid background in science, engineering, mathematic and history and when I hit the wall I was not helpless as those that only knew what a computer is and knew a few computer languages, two artefacts created by the mathematical physical culture of the 19th century in the middle of the Laplacian universe.  A direct incarnation of the mind body separation built-in cartesism of modern science. If this your only culture we wont be able to get out.  I had a tiny bit of culture which allowed me to began my search out of this mess.

  • Ravi Thakur added an answer in MCF-7 Cells:
    Has anybody worked with xenograft model of rabbit for tumor using cell line?

    I am working on xenograft model of rabbit for tumor induction and I have certain issues in setting my protocol. Can anyone plz help me in this regard. I am working with MCF-7 cell line..

    Ravi Thakur · Central Drug Research Institute


    Xenograft means that you must be injecting the MCF7 cells (as you mentioned) in Rabbit. Well for that you may require immuno-compromised rabbits. To my knowledge immuno-compromised rabbits are not easy to make and easy to rare. 

    Alternatively a syngenic model is possible. Where  a rabbit cancer cells are injected into a rabbit. As cells belongs to same species there are lesser chances of immune clearance. I searched online and came across no rabbit breast cancer cells, you can try searching if one is available. 

    In this case you can think of a third option, inducing a tumor using carcinogens. MNU, DMBA, B[a]P are some carcinogens used to induce tumors in rodents like mice or rats. You can try one in rabbit. 

    I don't know what kind of experiments you are planing. But in general. it is always better to use a mice or a rat model for cancer studies. Immunocompromised mice are available commercially, you can inject MCF7 to get tumors.

    Alternatively 4T1 mouse mammary epithelial cells are also available with ATCC. They form tumors even in normal Balb/c mice. This model works well if one does't have access to immuno-compromised mice.

    Though, there are limitations with both xenograft and syngenic models. Xenograft works well to study in-vivo effects on human cancer cells and syngenic works well if one want to study  tumor (mouse) biology in physiological conditions. You can chose one according to your problem.

    All the best.

  • Paweł Linek added an answer in Ultrasound:
    Is ultrasound a validated imaging technique to measure muscle mass, muscle fat composition and thickness in human skeletal muscle?

    I am looking at using ultrasound to measure human skeletal mass especially TA and gastroc muscle. I want see if ultrasound is as validated as MRI in defining above parameters. Any advise or suggestions welcome. Thanks

    Paweł Linek · The Jerzy Kukuczka Academy of Physical Education

    In general I agreed with above opinion. If you look at other muscles, you can see that such simple parameters like thickness or CSA are depends on operator's skills, experiences and the like.

    But In Recently published paper, the authors claim that ultrasound is appropriate and useful for evaluating skeletal muscle mass.

    Look at:


    It may be helpful.



  • Hana Bensalem added an answer in Video Analysis:
    Is there any behavioural coding scheme I can use to measure Sense of Presence?

    I will run an experiment with a driving simulator and oculus rift. I would like to analyse the behavioural responses through video analysis. Does anyone know a scheme of behaviours that is correlated with Sense of Presence? 

    the question is:

    what is presence and wich part  could your envirment detect?

    so,in your answer  you found the  scheme.

  • Patrick Druggan added an answer in Agar:
    How can I inhibit fungal growth in nutrient agar without affecting the pH of the agar?
    Specific antifungal to use and measurements.
    Patrick Druggan · Synergy Health, Chorley, United Kingdom

    cycloheximide or amphotericin B. 

  • Raid Amin added an answer in E-Learning:
    What are the top effective roles of instructors should be focused for fully e-learning course operation?

    I am trying to get the answers to the question "What are the top effective roles of instructors should be focused for fully e-learning course operation?"

    Raid Amin · University of West Florida

    Our entire graduate profram is taught simultaneously online and face to face. I have some students in the class rom, while other students are distance students. All lectures are taught synchronously live to all students. All lectures are recorded,  and all lectures are posted online. Students work in groups, with extensive student mentoring and discussions.

  • Does “spin” imply physical rotation?

    The “spin” of an electron or other fundamental particle is often described as “intrinsic angular momentum”. This terminology is required because a point particle or Planck length vibrating string cannot possess ½ ħ of angular momentum. Larger objects such as molecules or electrons in atomic orbitals possess quantized angular momentum which can be demonstrated to involve physical rotation. For example, a carbon monoxide molecule in a vacuum can only rotate at integer multiples of 115 GHz which is integer multiples of ½ ħ. Therefore, do you believe that fundamental particles have a physical angular momentum that is currently not understood? Alternatively, is "intrinsic angular momentum" an accurate description of spin because it is a quantum mechanical property that does not involve physical rotation?

    Charles Francis · Jesus College, Cambridge

    Sanjay, essentially, yes, but a Dirac spinor is a four spinor. It has four degrees of freedom, to describe antiparticles and particles as well as the two spin states.

  • Raid Amin added an answer in MANOVA:
    Is it ever correct to use ANOVA for multiple dependent variables?

    As far as I understand, if one wishes to analyse multiple DVs, MANOVA should be used. Risk of Type I errors will be increased by performing multiple ANOVAs or multiple t-tests without corrections. However, I have seen several publications where a single ANOVA is used and multiple DVs are entered as a factor. Is this ever advisable, and if so what is the rationale?

    Thank you

    Raid Amin · University of West Florida

    It is difficult to give a correct answer to an open question. If I knewabout so e experiment, I could maybe discuss the models that could be used for reasonably good results. The researcher decises which caraibkes are respobse varaibkes and which variables are classification factors. Each approach addresses different hypotheses.

    Typically, the variables of interest are the response variables that we want to study.

  • How may the new revenue standard affect earnings quality?
    Do you expect the new revenue standard increase or decrease earnings quality?
  • Do you or anybody you know run a support group for eating disorders in a rural or remote setting?

    I am currently exploring the capacity in setting up a support network in regional victoria, Australia for people with eating disorders, issues with body image and body dysmorphia. There are very few support groups which stand alone in the rural/remote setting and those which are available are based in metropolitan settings with outreach services in the country. Therefore, is anybody aware of any services available in the rural/remote setting (it does not need to be Australian specific). Regards

    Catiray Poiani-Cordella · Monash University (Australia)

    Great thank you Stephen

  • Barry Turner added an answer in Torture:
    Is the Nuremberg Doctrine a failure?

    The latest revelations about CIA torture methodologies demonstrates that medical doctors took part in what is euphemistically described as Enhanced Interrogation Techniques.  How is it that an international doctrine prohibiting medical doctors from involvement in torture has failed in one of the countries that presided over the Nuremberg Trials?

    Can we trust any nation that employs doctors in torture to simultaneously apply the principalist ethic Primum non Nocere in its hospitals and medical practice generally?

    Should those 'medics' be identified and disbarred for life from medical practice? 

    Barry Turner · University of Lincoln

    Before suing in 'world courts' its a good idea to check two things:

    • Who bankrolls them?
    • Who cares what they decide?

    The UK got sued in the ECtHR (European Court of Human Rights) on many occasions for torturing people who were its own citizens (well! they were terrorists)  in the 1970's.  The UK government ignored the rulings.  

    Sorry, I did not mean torturing, The UK does not do that... it was Enhanced Interrogation.

  • Dawood Sleman asked a question in IDS:
    How to Make a Diet Coke and Mentos Eruption?

    I want to know the chemical reactions that happen in this process, can anyone help me?


  • Paweł Linek added an answer in Validation Studies:
    How is the reliability and validity of SFMA for adolescent athletes?

    Can you provide the pdf format and reliability and validity studies for SFMA, it will be of immense help.

    Paweł Linek · The Jerzy Kukuczka Academy of Physical Education


    Look at an article in appendix.



  • Nicolas Perry added an answer in Welding:
    What macro etchant must be used for TI6Al4V to ascertain weld bead profile?

    Etching procedure for macro etch TI6Al4V.

    Nicolas Perry · Ecole Nationale Supérieure d'Arts et Métiers

    Hi, I used the Kroll formulation for etching

    Hf, HCL and water

  • Usman Abbas asked a question in Instruments:
    How to check the resistance of a peltier element?

    Peltier element is widely used in different instruments especially in biomedical insruments. I want to check the resistance of it. How can I do that?

  • Louis Brassard 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.



    ''Agre has criticized the usual assumptions of the received view in technical practice as follows:

    That perception is a kind of reverse optics building a mental model of the world by working backward from sense-impressions, inferring what in the world might have produced them.
    That action is conducted through the execution of mental constructs called plans, understood as computer programs.
    And finally, that knowledge consists in a model of the world, formalized in terms of the Platonic theory analysis of meaning in the tradition of Frege and Tarski. (2002, p. 132)
    The dissociation of mind and body (the founding metaphor of cognitive science and modern philosophy) is here at work,''

    I came to the same rejections on my own in 1993-94

    'That AI research has been framed along these contingent oppositions makes it clear that it is part of the history of Western thought''

    I followed that historical thought trails too as a way to see the light.

    In this investigation when I met Bergson  I renewed by an old youth experiential fascination with time and this was a major factor for my thesis.  I became experiential again , as in my youth, and became responsive to my perception, intuition and feeling and these became the driving force of my research and not my prejudiced intellectual conceptions.  I thougth of visual perception not as inversing the imaging process but as connecting to the world of surface through the connection to the image world.  Connection is not representation but a pointing to.  The pointing to has a structure. It become a physics of the pointing to.

  • Patrick Druggan added an answer in Estrogens:
    Why are there two peaks on the chromatogram for one ion?

    I injected BPA and estrogens,  and used a 100mm column to separate them. Detected by MS in sim mode.

    Then I found out, for example: for BPA, there are two peaks: normal peak as expected with small retention time and another peak later (long RT).

    Does anyone know why?


    Patrick Druggan · Synergy Health, Chorley, United Kingdom

    pH should not cause two peaks due to the dissociation of the molecule. It would simply give a broad peak as the ionic state is not fixed but is a probability.

  • Mohamed El Naschie added an answer in M-Theory:
    Which are the mathematics of the M-Theory?
    In 1994, Edward Witten of the Institute for Advanced Study and other researchers suggested that the five different versions of string theory might be describing the same thing seen from different perspectives. They proposed a unifying theory called M-theory, in which the M is not specifically defined, but is generally understood to stand for membrane. M-theory brought all of the string theories together. It did this by asserting that strings are really one-dimensional slices of a two-dimensional membrane vibrating in 11-dimensional space.
    Mohamed El Naschie · Alexandria University

    what is exactly your question ? witten have also a mode of 5D brans in 11D. this model  has 528 states .together with E8E8 THIS IS  1o24  .That means 2 to power of 10.here 2 is the Hausdorff dimension of a quantum path and 10 is superstring dimension.

  • Measuring Pleasantness / Unpleasantness together with Galvanic Skin Response and Heart Rate Variability?

    Hi dear all!

    In our study we are showing the participants (as potential customers) various types of advertisements and recording their response (microsiemens values) simultaneously thorough Hrv and Electrodermal Activity. I am curious to find out what the microsiemens values would be for instance when the participants like or dislike the ad? In other words would the microsiemens values increase or decrease and how in these emotional states (of like / dislike)? How would we be able to determine like or dislike by looking at microsiemens values? I would be happy if you could provide info about the above.

    Rita Rueff-Lopes · ISCTE-Instituto Universitário de Lisboa

    I believe that those values only provide information in terms of the intensity of arousal, from which you can't directly infer the valence. However, there is strong empirical support for the fact that negative emotions have stronger arousal responses than positive ones, since negative emotions (or affect) normally instructs the body to react, the so called "fight or flight" reaction. Good luck with your interesting research.

  • Darlene Paliswat asked a question in Pediatrics:
    What are the most common types of unstable conditions or emergencies in the pediatric population?

    I am preparing a thesis and I hope to extend our current Rapid Response Team to incorporate the pediatric population for effective emergency care. What type of unstable conditions or emergencies do you see in the pediatric population?

  • Pasha Javadi added an answer in DCM:
    Are there any Normal Brain MRI dataset in .dcm file?

    my research is about brain tumor, i was searched information about normal brain axial plane MRI dataset. i was found that extension file .nrrd , .img, but i dont find the dataset in .dcm extension. please help me.

    Pasha Javadi · Université de Montréal

    I don't think you need any account to download there, It should be open source.


  • Is there an admissible value for converting bacteria density estimates by agar plate counting into carbon or dry weight?

    It’s well known that bacteria morphometric measurements by microscopy or image processing (usually after staining) can be converted into carbon or dry weight using conversion factors available in the literature (Posch et al. 2001). I’ld like to know if there is  a conversion factor for converting bacteria density estimates by agar plate counting, into carbon or dry weight. Indeed, in the frame of a simulation test that I’m planning to run, I’ld like to use the datas that I found in the literature and which are expressed in bacteria density unit.

    Patrick Druggan · Synergy Health, Chorley, United Kingdom

    I don't think that this is possible. The colony is three dimensional while your measurements are in two dimensions. The variability in colony shape from different species would cause too much variation for the measurement to be of any real value.

  • Barry Turner asked a question in Universe:
    Will we ever meet our interstellar neighbours?

    Somewhere 'out there' in interstellar space are people like us, wondering if they are alone in the universe.

    Will we ever meet them to do the laws of physics prevent that ever happening?

  • James D. Korp added an answer in X-Ray:
    Which is the best (and user friendly) Single-crystal X-ray diffractometer on the market now?

    We are a research group in an academic institution and looking into buying a diffractometer for single-crystal X-ray studies of small molecules. We want an instrument combining excellent capabilities with a user-friendly interface and great customer support. Any suggestions on this? Thanks! 

    James D. Korp · University of Houston

    I have always had good results from Bruker CCD machines.   We recently purchased a Rigaku Rapid2 Image Plate and personally I'm very disappointed with it.   As mentioned by Dr. Rakovsky the software is truly horrible, but I also find serious problems with the hardware.   About 1/2 of all the samples I run have some degree of twinning, and an Image Plate machine is the worst possible choice for analyzing twins due to the way data are collected (in wide arcs that have all the spots superimposed onto a single 2-D image).   I find IP to be a completely obsolete method of data collection, and I would certainly avoid any IP machine if you are interested in accurate results on a wide variety of materials.  Bruker has the finest software available, since they collaborate directly with Prof. Sheldrick.    Their new "Intrinsic Phasing" routine is truly revolutionary.  

  • How significant is the discovery of Kepler-186f, an earth-sized habitable zone planet?
    Kepler-186f is the first earth-sized planet located in the habitable zone of another star that has been discovered. With this discovery, the search for life on other planets has entered into a new zone of discovery.
    Barry Turner · University of Lincoln


    I believe there are people out there and that is what they are, people.  As it stands at the moment we may one day hear from them but because of the distances we may never meet them.  

    We can only hope that what we know about the laws of physics are wrong and that interstellar space flight is possible, its just we have not worked it out yet.

    I think I will invite opinions on that in an RG question.