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  • Rafik Karaman added an answer in Aromaticity:
    What is the procedure for the reaction between substituted aromatic amine and substituted aromatic aldehyde so that complete reaction can be achieved?

    I am doing the reaction between substituted aromatic amine and substituted aromatic aldehyde. In this reaction, product i.e. imine has been formed but both the starting materials are present. Reaction does not proceed towards completion. Why is it so? Can anyone suggest the procedure for the complete conversion of  both the starting material to product?

    Rafik Karaman


    The reference to my answer depicted 1 day ago is:



  • Debra Sharon Ferdinand asked a question in Faculty:
    What strategies do you use to address late attendance in classes?

    While we have policies on attendance at our Universities, it seems late coming is not explicitly addressed, leaving faculty to use their own strategies to deal with late comers. ironically, the issue becomes even more complicated when you have to try and bring the late-comer into the "present" without keeping back the rest of the class. How do you deal with late coming and late comers in the classroom?

    Many thanks,


  • 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.

    Marc Tessera


    Now you have found a magic expression "pointer reading" which would be your last definitive argument.

    Please, be fair and try to argue with simple and clear words.

    You say, "I am not saying that no objections can be formulated against this discourse but the ones you brought have been answered clearly".

    Hence, it should be easy for you to clearly answer my question.

    I don't ask for references but only for simple, clear and rational arguments (I ask for references when data are required to support a given assertion).

    I think that here it is mainly a matter of logic.

  • Benhail Jaideep asked a question in 5G:
    Can anyone please help me in finding the latest research to help overcome problems of latency and maintain QOS in Intelligent Transport Systems?

    I have searched a lot on the web, I found the answer as 5G to be the answer to all the issues of latency faced in ITS. Could anyone please guide me?

  • Peter J Richerson added an answer in Climate Change:
    Are there authentic published work confidently pinpointing the sole anthropogenic factors contributing to Climate Change?

    Combined natural and anthropogenic factors (geologically recent phenomenon) govern Climate Change. It is, therefore, of paramount importance to discretely recognize the role of humans in Climate Change and to plan efficient strategy to mitigate it.

    Peter J Richerson

    Dear Syed, Kenneth,

    I think someone has already said in this thread that you-all seem to be after a level of certainty of evidence that science can't deliver except in the simplest cases. Science fits models to data and makes inferences based on the best-fitting models. The science we wish to deploy for policy-making purposes usually has considerable uncertainty associated with it. The earth's climate system is a good example, as the IPCC reports and the Alley report outline in detail.

    Applied ecologists have long recommended a strategy of "adaptive management" to deal with the problem of uncertainty in their field. Every management recommendation is the nature of an hypotheses and management itself is in the nature of an experiment based on an hypothesis. Monitoring responses to management helps detect mistaken hypotheses and revise recommendations.

    We will in the lifetimes of our children and grandchildren reduce the skepticism about the role of CO2 in the global climate quite a bit. If we don't control the CO2 increase, the climate either will or will not warm appreciably. If we do control  it, the warming will be less if the present models are correct, or the climate will do something else if they are wrong. We might well trigger some some sort of unpredictable feedback effects if the Alley Committee's ideas are correct, and learn a lot about one or more of them as a consequence. Embracing the current business-as-usual scenario increase in CO2 is equivalent to the hypothesis that CO2 is unimportant in climate dynamics, whereas the consensus view of climate scientists is that current and projected CO2 increase is quite dangerous. We have to pick our hypothesis in the face of an undeniably undesirable level of uncertainty.

    The IPCC's ensemble of models have a large range of predicted warming for the benchmark scenario and they do not even try to model all the many feedbacks that we know exist. The average predicted increase is about 2 C, quite close to Masters' simple calculation I recommended in my earlier post. Ladies and Gents, that is almost all the information we get to have until we live out a lot of whatever management option we decide to impose on the climate system. We are embarking on a one-world no control experiment. Pick your model and hope for the best! 

    Best, Pete

  • Lev Kra asked a question in Resveratrol:
    Are there any known chemicals that can potentiate the effects of Resveratrol?

    Or, are there any chemicals known to potentiate the effects of any DPP-4 inhibitor?

  • Karin Schermelleh-Engel added an answer in Mplus:
    Cronbach's alpha values in Mplus?

    Does anyone know syntax to get Cronbach's alpha values of scales being used in Mplus. I haven`t found the command. If anyone knows, please.

    Karin Schermelleh-Engel

    Saeng, I have enclosed a Mplus syntax for calculating omega for an unidimensional construct.

    Does this also help?

    Regards, Karin

  • Flourish Itulua-Abumere added an answer in Poverty:
    How does poverty affects one's well-being?

    In a developing country, I presume the way poverty is perceived is quite different from that of a developed country. How will poverty then affects ones well-being in a developing country? (most especially women). Will be nice if you can bullet point it. Thank you

    Flourish Itulua-Abumere

    A very special thank you to everyone. I appreciate the sources that have been shared here and insights. With regards to women in developing countries, how has poverty influenced there ways of life? Does poverty passes on to generations? 

  • Witold Orlik added an answer in Likert Scale:
    Which Likert scale should I prefer that of 1-4, 1-5 or 1-7?

    Hi everybody!

    I'm making a questionnaire for my students about my new teaching style. My question is about the best Lickert scale that I can use in order to they evaluate some statements: 1-4, 1-5 o 1-7? I have read about this, but there are advantages and disadvantages in each of them. Can anyone help me out?

    Thank you in advance.

    Witold Orlik

    Hello Montserrat, 

    I see little if any issue when choosing 7 over 5 Likert type of answer categories. I vote for 7, but decision is all yours.

    Best wishes

  • Marwa Emad added an answer in Solvent Extraction:
    What is a proper solvent to extract hexane(or other organic solvent) from organic oil?

    Willing to extract hexane from a lipid mixture, I thought of LLE as a cost-effective and easy alternative to remove hexane from oil. Simply put, I tend to use maceration with hexane to extract oil from organic compound, then using LLE extraction, remove hexane from the oil. What is the proper solvent to remove hexane?

    Marwa Emad

    i have the same condition of your plant, you can evaporate hexane solvent on rotary evaporator at 40 c not more, till no hexane odour and seal your extract perfectly to avoid any oxidation processes

  • Behrouz Ahmadi-Nedushan added an answer in Science, Technology & Society Studies (STS):
    Is there still a gulf between scientists and ‘intellectuals’? Which of them have more influence on people’s worldviews?

    Traditional intellectuals –thinkers, writers, political and social commentators, and artists- have historically played a major role in the diffusion of the ideas that shape the ways people see the world and their own society and lives

    In the prominent book The Third Culture (1995), John Brockman claimed that these kinds of intellectuals have “become increasingly marginalized”. They are being replaced by scientists who, “through their work and expository writing”, communicate directly with the general public. These “third-culture intellectuals” would be represented by the likes of Paul Davies, Martin Rees, Richard Dawkins, Steve Jones, Daniel C. Dennett, Brian Goodwin, W. Daniel Hillis, Nicholas Humphrey and many others.  

    The culture of traditional intellectuals, says Brockman, “dismisses science”, is “often nonempirical”, uses “its own jargon”, and “is chiefly characterized by comment on comments, the swelling spiral of commentary eventually reaching the point where the real world gets lost”.

    The idea of a Third Culture has its origin in C.P. Snow’s influential “Two Cultures”   essay (1959), in which the British scientist and novelist deplored the “mutual incomprehension” –“sometimes hostility”-- between science and the arts. Scientists shared a “culture” –no matter their political, religious, social class and even disciplinary differences-, with common attitudes, standards, approaches, assumptions and patterns of behavior, At the opposite pole, attitudes were more diverse, but the total incomprehension gave an “unscientific flavor” –often almost “antiscientific”— to the whole “traditional culture”. Moreover, scientists largely overlooked traditional literature, which they perceived as irrelevant to their interests, while most intellectuals were unable to describe something as basic as the Second Law of Thermodynamics.

    Snow saw such disconnection and polarization as a “sheer lose” to society and stressed the need to build bridges between the sides. In a second essay, published in 1963, he suggested that the gap would be closed by a “Third Culture” that would eventually emerge. In his version of this new culture, intellectuals would communicate with scientists.    

    Not long ago, a column in Scientific American stated that Snow’s vision “has gone unrealized” (see Krauss, Lawrence M.: “An Update on C.P. Snow’s ‘Two Cultures’”, August 17, 2009).

    What is your opinion? Is there such a cultural divide? Are intellectuals scientifically illiterate? Do scientists ignore the basics of the humanities? Which of them have more influence on the public? What kind of Third Culture –if any- is emerging?

    + 4 more attachments

  • Neha Qasim added an answer in Fluorometry:
    Difference between emission/excitation spectra?

    In fluorometry, when do we take the emission spectra and when do we have to take the excitation spectra of a particular sample....i mean theoretical definition i understand, but practically when and how do i differentiate them?

    Neha Qasim

     Thank you everyone!

  • Artur Burzynski added an answer in Intelligence:
    How can we relate spirituality to enhance research skills of PhD students ?

    Research is a complex multi-factorial process that encompasses issues at all levels from that of individual students and supervisors, to available infrastructural support, to institutional and governmental policies, structures and procedures.Numerous factors have been identified significant predictors of successful completion of research Spiritual intelligence is the central and most fundamental of all the intelligences.Robert Emmons defines spiritual intelligence as "the adaptive use of spiritual information to facilitate everyday problem solving and goal attainment. some essential life skills  are very important for successful completion of research work like problem solving, decision making, information management, time management, creative and critical thinking etc. My area of study is how can we use concept of spirituality to enhance the research competence of PhD students? Any information or suggestion will be of great help.  Thanks and regards.

  • Adam Karpf added an answer in Transgenes:
    What does it mean by derepression of a transgene?

    For ex: in the first hour after derepression of the transgene, ISGF3 is still detectable.

    I am working on presentating a paper article on Hepatits C research and that it inhibits the JAK STAT signalling. Please see attached paper. Having trouble understanding the Figures- mainly figure 2. 

    Adam Karpf

    I looked at Fig. 2, and understand your confusion.  There is a lot going on in this experiment for a beginner to understand.  It appears that the HCV core protein in this system is induced when tet is removed from the media (i.e. tet-repression system).  When HCV core protein is induced, which is a consequence of tet removal (see part B of figure), it interferes with IFN-alpha induced transcription factors to bind its target sequence in ISGF3 (EMSA assay on top).  You will note how the band goes away at later time points in the IFN-alpha + lanes.at later time points after tet removal.  I hope this helps.

  • Clodagh Nugent added an answer in Child Care:
    Can anybody help with an Irish Private Residential Child Care Sector- Staff turnover?

    For my dissertation I am researching organisational factors contributing to high turnover rates in the private sector. I would like to be able to identify the main reasons that people leave one organisation to work for another, in the same role. This knowledge could largely benefit young people in the care of the state who have developed attachments to carers, and ultimately contribute positively to continuity of care.

    Any information/ publications deemed relevant or associated with this topic would be greatly appreciated.  

    Clodagh Nugent

    Béatrice Marianne Ewalds-Kvist, & Mary C R Wilson  Ii cannot thank you both enough.  You have reaffirmed my belief inn humanity and existence of the altruistic spirit.  I hope some day to be in a position to return the huge favour


  • Radomir I Slavchov added an answer in Glycols:
    Is it possible that a contact angle of water/ethylene-glycol mixture on the surface of calcite is a non-monotonic function of water concentration?

    Dear All,

    Is it possible that a contact angle of water/ethylene-glycol mixture on the surface of calcite is a non-monotonic function of water concentration? That is at full water concentration the contact angle is about 60 degrees, while at full glycol concentration, the contact angle is about 120 degrees, while at 50 % of water concentration in water/glycol mixture (molar fraction) the contact angle is about 45 degrees?

    Which theory explains a non-monotonic dependence of contact angles for aquifer solutions?

    Thank you and best regards,


    Radomir I Slavchov

    Dear Alexander,
    No, I don't know any, but I'm pretty sure you can find it. Try to search for studies that use data for contact angle to determine adsorption.

  • Mohib Ullah asked a question in Hydrazine:
    Please can any one tell me the Hydrazine reaction condition Dimethylacetamide (DMAc) medium with reference?

    e.g. functionalization of CNTs with hydrazine in the N,N-Dimethylacetamide slovent...under what conditions it will react like temperature, time etc. 

  • Lyelle Palmer added an answer in Teaching Methods:
    Can anybody suggest references for research in physical activity for preschool children - best teaching styles?

    I would appreciate if anyone could suggest good research about the most effective teaching styles in physical activities for preschool children.

    Lyelle Palmer

    We should communicate through email, Aleksandar, because at the Minnesota Learning Resource Center in Minneapolis trainings are conducted for the most advanced and effective school readiness programs PreK-4th grade.  Over 6000 teachers have been trained in school teams (including the physical education teacher) for brain stimulation in the classroom, gymnasium/floor and playground.  A huge part of the program is movement activities that produce high levels of agility and coordination, strength, endurance and flexibility.  School readiness in America is a problem that produces too many students in need of special education.  Compared to norms, half of the students in the Stimulating Maturity through Accelerated Readiness Training (SMART) program achieve at the 75%ile on formal and informal tests.  I am a co-developer of this program that integrates movement stimulation for kinesthetic, tactile, visual and auditory stimulation to produce unprecedented results.  The program includes movements that inhibit retained primitive reflexes that produce discomfort and unpredictable actions.  We include mobility coordination for fire escape safety, sighting eye dominance, correct handedness related to language hemisphere, eye motility, eye fixations, eye convergence, visual field expansion, vestibular stimulation (sliding, rolling, spinning), etc, all of which impact comfort in sitting in class, increasing ability to concentrate and pay attention, and deep joy in body exertion, thrills, and social participation. A separate training class for pre-kindergarten teachers is now available.  Young children must move, and some moves are better than others.  We should talk.  Lyelle


  • Jan Piwowarski added an answer in Western Blot:
    Has anyone done western blot for PDX 1 protein ?


    I am doing western blot for PDX1 protein. I am getting a band near 46KD but also there are some bands coming at around 100kd. I am using rabbit polyclonal for PDX1. 

    When checked in the pancreatic lysate the band is coming at around 40KD.

    unable to understand why the band is coming at around 100KD.

    Phosphorylated form of PDX1 comes at around 46KD and its unphosphorylated form comes at around 31KD.

    Jan Piwowarski

    Dear Anshu,


    all the answers are there ;)

    best - jan

  • Marcelo Silva added an answer in Cancer Cell Line:
    What is the difference between various breast cancer cell lines?

    Why do researchers apply different cancel cell lines for their research purposes? 

    I know that the cell lines differ in "invasiveness" potentials, but what does this mean? for example what is the difference between MCF-7 and MDA-MB-231?

    Marcelo Silva

    The Ali answer is complete. It is important to note that MDA-MB-231 did not express the FGFR receptor.

  • Andreas Oberhofer added an answer in Yoga:
    What is the yogic management for cervical spondylosis?

    Some of the Yoga experts suggest neck rotation in the problem of cervical spondylitis, whereas some suggests not to perform this practice. Can we get the right answer?

    Andreas Oberhofer

    Dear Narendra Deo, rotating carefully and smoothly may work, but as the cervical spine is not a ball joint it even more may damage as well. Rotation may improve circulation and therefore help. It is less dangerous to perform isolated movements: turning right - left, bending right - left, bending forward - backward, ...

  • Tom Tsui added an answer in Ovarian Diseases:
    Does anyone have a complete rule out list for lower right quadrant abdominal pain?

    16 year old female.  Complains of right lower abdominal quadrant pain.  Via ultrasound and CT cystic ovarian disease, ovarian torsion and appendicitis have been effectively ruled out. 

    Tom Tsui




  • Martin Thoma asked a question in Computer Vision:
    Is there a difference between “classification” and “labeling”?

    (The following is only a copy of the same question - http://datascience.stackexchange.com/q/9074/8820 -  I've asked on StackExchange)

    Until recently, I thought that "labeling" and "classification" are synonyms. But when I started another question about [terminology in computer vision](http://stackoverflow.com/q/33947823/562769) I thought about it: Is there a difference between "labeling" and "classification"?

    I thought that the "class" is the concept you want to detect and "label" is what you assign to data. So the "class" is a concept which leads to the data and "label" is only the name. Hence "labeling" would be the same as "classification" as both want to make a statement about the underlying class which lead to the data.

    ## Articles

    A quick search via Google Scholar revealed that some articles use both terms in the title:

    * Markus Eich, Malgorzata Dabrowska, and Frank Kirchner: "Semantic Labeling: Classification of 3D Entities Based on Spatial Feature Descriptors"
    * Chunlin Li, Dmitry B. Goldgof, and Lawrence 0. Hall: "Knowledge-based classification and tissue labeling of MR images of human brain"
    * Ray Blanchard: "The classification and labeling of nonhomosexual gender dysphorias" - another research area but probably it is the same difference between the two words?

    So I guess there is a difference between "labeling" and "classification". What is the difference?

    ## Google N-Gram

    [![enter image description here][1]][1]

    classification seems to be a much boarder term.

    [1]: http://i.stack.imgur.com/zpn9y.png

  • Adam Karpf added an answer in Exons:
    Does anyone have clear illustration of a gene? Does TSS = first exon?

    Where exactly the TSS lies? does TSS always lie at beginning of the UTR? 

    Does +1 usually defines the transcription start site, or the translation start?

    I doubt, however, that these things are not written on any book of biology.

    I'be so much grateful if you can give well illustrated reading material of gene structure/ anatomy. 

    + 1 more attachment

    Adam Karpf

    TSS is defined as the transcriptional start site.  This is where RNA polymerase begins transcribing the DNA.  This is also the beginning of the UTR (untranslated region), assuming that the gene has a 5'UTR, which is typically the case for human genes.  The +1 nomenclature can be used to indicate the first base transcribed, or the first base translated, depending on context.  In genomics, +1 generally refers to the first base transcribed.  When cloning expression vectors, +1 usually indicates the position of the ATG or the first codon of the translated unit.  Hope this helps.

  • Miles B Markus added an answer in Vivax Malaria:
    Is necessary to have glucose 6 Glucose-6-phosphate dehydrogenase level in every setting where there is vivax malaria?

    Is necessary to have glucose 6 Glucose-6-phosphate dehydrogenase level in every setting where there is vivax malaria?

    Miles B Markus

    Good question.

    Relevant information is to be found in the recent publication entitled: "The challenges of introducing routine G6PD testing into radical cure: a workshop report". It can be viewed at:


  • Luiz Costa added an answer in Public Sector:
    Can anyone recommend literature on "Impact of globalization on public personnel recruitment"?

    I'm interested in exploring the relationship of globalization and public sector recruitment in the case of developing countries.

    Luiz Costa

    Dear Hidayat,

    I think you'll have difficulty to find this kind of literature because there is no relationship between globalization and public sector work. In this sector, the principal rule for recruitment is that: the person must have national birth . Only national people can participate on public recruitment. Themes of national security have treatment by national public service. Normally, the countries do not recruit not national people. This rule is extended to the public service of provinces and municipal public service.
    Best regards and good luck with your research.

    Luiz Paulo

  • Ehsan Sharifi asked a question in Symbolism:
    How to separate positive and negative symbolic variables of an equation to the left and right sides of the equation in MATLAB?

    for example we have this equation :
    3*a - 2*b + 5*c - d = 0 

    First I need to separate positive and negative variables to both side of equation:
    3*a + 5*c = 2*b + d

    and then take only the coefficient of each symbolic variables:
    3 + 5 = 2 + 1 

    Thank you 

  • Otto E. Rossler added an answer in Special Relativity:
    Can someone re-write the Einstein field equations in such a way that c becomes a global constant?

    I recently showed that the equivalence principle observes this constraint. This fact is trivial because the equivalence principle is based on special relativity alone.

    Therefore, the full field equations must be capable of being re-written in this form. Otherwise, the equivalence principle would no longer fit in.

    So the proposed transform sought is the so far missed "physically correct version" of the Einstein field equations.

    Otto E. Rossler

    Dear Stefano, your "unfortunately c is constant only locally" is the problem, not the solution, right?

    A return to the still naive but stronger pre-1911 Einstein can be called for.

    I am guilty of a recent little note to this effect: http://www.ptep-online.com/index_files/2015/PP-43-09.PDF

    But what is needed is the help of the strongest young specialist: right?

  • Adam Karpf added an answer in Molecular Biological Techniques:
    How can I explain different effect of overexpression on exogenous end endogenous mRNA?

    Recently, I've got very strange phenomena.

    When I transfected a plasmid expressing protein 'A' with a plasmid expressing reporter mRNAs, which harbor specific 3' UTR, into HeLa cells, over-expressed protein 'A' repressed expression of the reporter mRNAs. However, over-expressed protein 'A' increased level of the endogenous mRNAs.

    I don't know what it happened in cells, and I don't understand why over-expressed protein 'A' have made different effects on both the reporter mRNAs and the endogenous counterpart.

    Is there anyone who has ever experience such case?

    Adam Karpf

    This is an interesting question.  Let's assume there is also an endogenous form of "protein A" and that it regulates the endogenous mRNAs.  Thus, when you transfected in and overexpressed the reporter mRNAs, maybe you altered the stochiometry of the system such that you have bound up most of the endogenous protein A (as well as the transfected protein A) with the reporter mRNAs.  The reporter mRNAs may have increased affinity to protein A and become downregulated/degraded.  However, the endogenous mRNAs are no longer under negative regulation by the endogenous protein A, due to lower affinity to protein A, and you see increased levels of the endogenous mRNA.

  • Refik Kanjhan added an answer in EGTA:
    How to prevent rundown of NMDA currents in cultured hippocampal neurons?

    I am doing whole cell recordings of NMDA-evoked EPSCs in cultured hippocampal neurons, P14-17, holding at -70mV. I apply a three second pulse of NMDA (5 microM) every minute, while bath applying other drugs, looking at WT and transfected cells. However, I am regularly getting run down of my NMDA-evoked currents, which is making it difficult to discriminate real drug or mutant effects. Although I might get a window of baseline to bath apply a drug, the rundown obscures any wash off. I have some okay data using this protocol, however it would be ideal to remove the confounding effects of rundown as the rundown limits how confident in the results. Does anyone have any advice on how to get over rundown? Here are my bathing and internal solution recipes…

    Bathing Control Kreb’s solution – TTX 500nM, Bicuculine 50uM, D-Serine 10uM, Magnesium free, 2.5 mM Ca2+

    Internal solution – KCl internal, with TEA-Cl, QX-314 (2mM), Na-GTP (0.5mM) and Mg-ATP (2mM)., EGTA (5mM)

    My two thoughts were to up EGTA conc and also add phosphocreatine to internal?

    Thanks very much,


    Refik Kanjhan

    Dear Donald,

    I would not recommend increasing NMDA, you are right, increasing agonist will only enhance rundown. At the end what you want is not the maximum-response but a clearly measurable (signal to noise) response that is repeatable and sustainable by cells.

    best wishes,