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  • Paul R. Carr added an answer in Racism:
    How can, and should, we measure the impact of the hegemony of research production and dissemination in English?

    I am wondering what is lost, neglected, omitted and/or diminished but the increasing insistence on publishing primarily or exclusively in English. Does this mean that researchers do not read in, engage with, and publish in other languages? My primary concern is the assumptions, hypotheses and contextual notions that are used, which privilege one language above all others. Similarly, I'm wondering if English-only speakers, or those doing research only in English, are willingly and unwillingly disregarding or underplaying other ways of thinking, other epistemologies, other insights, etc., simply because of the hegemony of language. Whenever I have presented in French and Spanish, I am always heartened and taken aback by the different types of questions, elaborations and approaches, and believe that the lack of engage in different languages and within different linguistic contexts may have a detrimental effect on the salience of the research. Of course, this is not a criticism of research that is produced in English, per se, but is more directly at the systemic underpinning of discounting other types of research. The socio-linguistic literature has raised some interesting concerns in this area. One specific case in point is the way that racism is discussed in different languages, including the theoretical, empirical, linguistic and vernacular expressions that frame the topic (it is quite different in English and French, for example). In sum, more engagement across linguistic, as would be the case in ethno-cultural, racial and other, lines would be a beneficial part, I believe, of any evolving social science research.

    Paul R. Carr · Université du Québec en Outaouais

    Thanks, Phan, and I hope that all is well. I was at Monash U. as a Visiting Scholar for a month in 2013, and enjoyed the experience but see that you are no longer there now. The sociolinguistic debate plays out daily in Canada, and there has been a great deal of cultural and linguistic assimilation toward English but the French language is still alive and well. The problem of resources--actual books, texts, media, culture, games, internet, etc.--is a constant challenge but much can and is being done. Of course, developing a language base is critical, and publishing in languages other than English is one important step. Best regards. Paul

  • Paul Weldon added an answer in Lipid Extraction:
    Does anyone know of a lipids extraction of mouse brain protocol? Is it possible to do this despite the fixing of brain?

    I would like to extract free fatty acids, to analyze resolvins (lipid mediators which resolve inflammation) on mouse brain sections. And these brains were fixed in PFA. After fixation, the mouse brain are keep in cryoprotector medium at -20°C. After lipids extract, I would like to see resolvin with enzyme immunoassay.

    Paul Weldon · Smithsonian Institution

    Any of the solvent systems that Dr. Lasker mentions are worth trying. Make sure you extract control samples to exclude fixative contaminants/artifacts. TLC is a good preliminary method to examine your extracts. Good luck.

  • What are adequate instruments for measuring Indoor Air Pollution (CO and PM) for only 1-2 hours during the combustion of biomass?

    We would like to measure Indoor Air Pollution, in particular CO and PM 2.5, in rural, poorly ventilated kitchens during the preparation of meals. This means that the measurement won't take longer than 1-2 hours. Do you know any measuring devices that would be suitable for our purpose and that are sensitive enough to capture pollution also during that short period of time? Can you recommend CO dataloggers? Or would you rather recommend CO diffusion tubes?

    Also, do you know a low-cost instrument for measuring PM that is easy to handle? As far as I know they are all quite expensive.

    Thank you.

    Tsuyoshi Ochiai · Kanagawa Academy of Science and Technology

    I would suggest you to measure CO using a COX-3 CO/CO2 analyser (Sibata Scientific Technology Ltd., Saitama, Japan). We recently published about field performance test of an air-cleaner with the data of CO concentration using the analyser (Molecules 01/2014; 19:17424-17434; it is available on my ResearchGate page).

  • András Bozsik added an answer in Medical Education:
    Can we measure motivation in students?Are there any standardized questionnaire to measure?

    This question is regarding medical education.

    a) How will we know that a student is motivated to learn the subject ?

    b) Is it intrinsic motivation or extrinsic motivation?

    András Bozsik · University of Debrecen

    Dear All,

    Students’ motivation is difficult to recognise and classify. However, to recognise the lack of motivation may be easier. Practically, I feel but - fortunately – I can survive the unlimited indifference of students. I have hoped – of course in vain – I can a bit improve students’ motivation toward a subject showing them the interestingness, imagination, the horizon of opportunity of a given subject as well as their touching points with culture (art, Belles-lettres, music , their historical development etc.). Unfortunately, I teach such prosaic subjects like entomology, ecology, biological control. Last year I have prepared a test in order to measure the knowledge of my students compared with the comprehension of Maria Sibylla Merian, the well known artist entomologist of the 17th century.


    I planned to get an international comparative material but I have not known in that time how difficult is it to persuade RG members on a tiny extra work. Thus, my result was a normal but disappointing fiasco. I consider that indifference of teachers (burnout) is even more unacceptable.

    Intrinsic motivation cannot be planted into students but can be increased and cared. To form extrinsic motivation inside of a student would be a great challenge for teachers.

    During my about 30 years of carrier I have met only one or two students who had some intrinsic motivation toward entomology. As to my success to convince students on the beauty of entomology, the number of persuaded student was 3 or 4.

    Regarding ecology, the rate is much worse.

  • Matthew Star added an answer in Biofeedback:
    How to induce a negative emotion such as angry ?

    I would to know the suitable method to induce human emotion especially negative emotion such as angry. I will do an experiment using biofeedback sensor.

    Matthew Star · University of Hawaiʻi at Hilo

    Tell him what a jackass he looks like with all those EEG wires on his head. Or better yet, shock him repeatedly while forcing him to listen to Rush Limbaugh.

  • Claude J Spicher asked a question in Allodynia:
    Where - and how - are you testing tactile hypoaesthesia in Neuropathic Pain Patients?

    We are used to read: Neuropathic pain and other somatosensory abnormalities (Lindblom & Verillo, 1979; Jänig & Kirillova, 2013). Then if we are reading carefully, authors usually decribed hyperalgesia or mechanical allodynia (Gierthmühlen et al, Nature Reviews Neurology 2014). But where - and how - are you testing the third somaesthetic clinical examination sign: Tactile hypoaesthesia ?

  • Mathias Kirchmer asked a question in Big Data:
    What have Big Data and Anlytics to do with Business Process Management (BPM)?

    Big Data and Analytics are focused on transforming big quantities of data into usable information. I believe this information will only have value in the context of an appropriate adjustment of related business processes since that is the only way of moving the information into action. Thoughts? How do you organize the connection? What dos that mean for BPM?

  • What is the best linker for a fusion protein?

    Hello everyone, I am preparing a fusion protein with mCherry and I have doubts about the type of linker to use. I have seen in the literature that sometimes flexible linkers of this type of sequence are used: (Gly-Gly-Gly-Gly-Ser)n. Can an expert in the field confirm whether this residue composition is the most suitable? What would be the optimal length?

    Thank you for your help.

    Dominique Liger · Université Paris-Sud 11

    Hi there,

    I have evaluated the effect of (Gly4Ser)2 spacer on mIL3-mediated diphteria toxin   toxicity: the presence of the spacer significantly improved toxicity. If interested, the article published in FEBS Letters in 1997 is accessible from my researchgate contribution page.

  • Mathias Kirchmer added an answer in Social Media:
    Do you have examples of innovative business processes enabled through Social Media?
    Social Media become more and more important on the enterprise level. Companies use e.g. LinkedIn to support hiring processes or Facebook to support marketing. Do you have good examples for the use of Social Media enabling innovative business processes? This includes the use of "in-house" social media technologies.
    Mathias Kirchmer · BPM-D

    Thanks. Great Input.

    Any specific business processes supported by Social Media, other than the typical marketing and HR examples?

  • What is the time factor for the separation of blood and serum?

    I am a field deputy medicolegal investigator and often have questions regarding scenes. The blood was beginning to coagulate and separate.  What would be an approximate time for this to occur? The scene was inside and the temperature was about 75 degrees.  I need to estimate the time of death. Rigor was absent. 

    Steingrimur Stefansson · HeMemics Biotechnologies Inc

    Hi Carole, this is a very interesting problem, but I am afraid that there  is no universal metric on how fast blood clots.

    There are so many variables. If the victim was taking aspirin, Zoloft, alcohol, opioids, etc that inhibit platelet function and/or inhibit normal liver production of clotting factors, then it is almost impossible to determine anything from a blood sample at the scene.

    Additionally, blood coagulates differently depending on the surface that it is deposited on.

    Sorry I couldn't be of more help.

  • Ken Toyama added an answer in Refractive Index:
    Can anyone help with Kramers-Kronig relation in active waveguide (e.g, InP)?

    The real part and imaginary part of refractive index of a bulky material comply with the Kramers-Kronig relation, does the same apply for the effective refractive index and the modal gain in an active waveguid structure (e.g, a double heterostructure semiconductor laser)?

    Ken Toyama · Juniper Networks, Inc.

    The Kramers-Kronig relation is fairly fundamental because it comes from causality assumption (no output before input).

    In fact we can use this to make a phase modulator in III-V semiconductor junction.

  • Mathias Kirchmer added an answer in BPM:
    What impact does Cloud technology have on the management of business processes?
    More and more organizations think of procuring their information technology through "the cloud". Hence, what remains in the organization are just the business processes supported through those could based applications. What impact does that have on business process management (BPM)?
    Mathias Kirchmer · BPM-D

    Great input. Thanks.

    Does somebody have examples how the provision of software though the could changes IT departments or maybe even make them report to the BPM organization?

  • Which method can work out detection of consumed glycerol by bacteria via using a simple titration method?

    Hey Everyone,

    I am trying to make my bacteria use glycerol as their only carbon source. I am using E.coli in minimal medium by providing only pure and crude glycerol from the biodiesel industry. They are consuming the pure and crude glycerol that I can understand by looking for growing of E.coli OD600 nm in UV-Vis spectrometer.

    But I have to prove that by concentration difference, so UV is not suitable for glycerol detection and I tried a titration method which I found literature for crude glycerol detection from biodiesel industry (starch and KI as an indicator). However, I couldn't get the true result. I need some suggestions.

    How can I calculate the consumed glycerol by bacteria easily (and cheAply of course)?

    Thanks in advance.

    Júlio Cesar De Carvalho · Universidade Federal do Paraná

    Dear Dilek, 

    190nm is so deep into uv that even some quartz cuvettes will absorb, check the quality of yours. Also, several substances absorb heavily in the uv range, especially those polyunsaturated and aromatic. Metabolites from you culture, even in low concentrations, may easily interfere. However, this wavelength works in HPLC, for several substances, and will work for glycerol (it is not specific, but the separation should be, and the peak could be identified by its retention time) 

    But you seem to be interested in a colorimetric method, or something simpler. Do you expect to have a high concentration of metabolites, or are you producing biomass? If glycerol is the most important solute, and you don´t expect other soluble products, you can centrifuge the sample and read the density, refractive index (or Brix). That will give you an approximate concentration and shall prove that glycerol is being consumed through fermentation, but you are advised to check for other metabolites at some point in your research.

    There is plenty of colorimetric methods based on the derivatization of glycerol, e.g. http://www.analiticaweb.com.br/newsletter/08/AN51853_Biodiesel_UV.pdf. However, you may have interference of metabolites such as simple organic acids.

    As for the method you tried, is it based on the gelatinization of starch? Do you expect it to be precise? 


  • Janice e Marquez asked a question in Freedom:
    If public opinion on gay rights is shaped by personality in context then why not Christians?

    We are different in thoughts, behavior and lifestyles yet we are thwarted, made fun of, put in prison, "shut upped" and persecuted (in other countries) for who we are. The US constitution states freedom of religion; but what they want is to take our freedom away!

  • How can I measure the effects of Li on the Wnt signaling pathway?

    I use LiCl to active Wnt- B catenin signaling pathway. I use NaCl as control to be sure that  Cl has no  effect on Wnt activation  and just Li work as activator  .

    beside NaCl what should I use to be sure the whole result is because of just   Li ? 

    Mikhail V. Shepelev · Russian Academy of Sciences

    Hi all!  I was trying to use LiCl to activate  Wnt signaling and measure the luciferase activity of either TOPFLASH reporter or promotor region of my gene of interest.

    So it was HEK293, 25 mM LiCl and 25 mM NaCl, 24hrs, DLR assay from Promega.

    The problem is: I observed about 10-fold increase in Renilla luciferase activity, it was the same for both RL-CMV or RL-tk.  Therefore, I cannot interpret the data from these experiments, since it looks like LICl treatment non-specifically activates transcription or enzyme activity of Renilla luciferase.

    Did anyone observed similar effects??? I was expecting RL activity to be pretty much equal across samples. Also, other people in the did this assay in other cells, and they did not see any changes in Renilla activity in such way.  So, I'm confused. Any suggestions would be appreciated!!

  • Is mental representation innate?

    In Before and Beyond Representation, Lambros Malafouris’ proposes that enactive mark-making bootstrapped the Paleolithic mind into representation, both internal and external, This allows that representation may not be an innate capability, but a property of human culture, propagated via cultural training.What evidence do we have, ie in developmental psychology or anthropology or neurology, that internal representation is either innate or learned?

    Jelle van Dijk · Utrecht University of Applied Sciences

    Hi Simon,

    Did not have time to fully read this thread but your question made me think of two interesting works.

    One is a famous discussion between Fodor and Piaget edited into a book by Piatelli-Palmerini. If you can get your hands on it it is a nice historical document. (See the introduction for download here: http://dingo.sbs.arizona.edu/~massimo/publications/)

    I never interpreted Fodors defence of innateness in that discussion to be a joke, and I know of people that wrote Phd's on it, but perhaps they were all fooled, which is a real possibility. He is a jokey guy. But regardless of his humour, his starting assumption that learning concepts consists essentially of hypothesis testing on the world is what is wrong imo and as this is basically what underlies Cognitivism, so is Cognitivism.

    The other reference is a book that might now seem a bit outdated but it is a nice book on (against) innateness written when connectionism was at its height: Jeff Elman and many authors, Rethinking Innateness.

    Btw I think the definition of representation need not make any reference at all to the brain. I like the definition by Haugeland, which goes something like: A representation is an object that is used by a system as a stand-in for something else (presumably because the something else is not reliably present or accessible but needed nonetheless). Most representations are in fact external man-made artefacts, and it is my conviction that all representations are external man-made artefacts, and that we have wrongly come to mistake our own brain activity patterns for the kinds of things only complete living human beings (with brains in bodies in action), situated social settings, can produce.

  • To purchase suitable gaussian version?

    I  want to  minimize the energy of organic molecules that are used in my study, I have checked on internet and found that the gaussian 09 rate is $1150. It is expensive, Please tell me how I can purchase a cheaper version suitable for my studies?

    Rama Viswanathan · Beloit College

    I have developed a front-end graphical user interface (works only on Macintosh computers) for firefly/GAMESS:

    Create structure with macmolplot

    import structure into my front-end app

    click run with choice of method

    you are done.

    I have no idea how well this works for serious computations, have used it in teaching with small molecules, if you want to volunteer to help debug, I can provide you with the binaries!

  • Pedro Machado added an answer in DSP Processor:
    How do you proceed with implementing or interfacing a sliding mode controller to an actual circuit?

    I am working on designing of a sliding mode controller for a solar power system.

    I want to know which is the best choice to implement the controller: micro-controller or FPGA or DSP processor?

    What issues should I take care of while going for implementation?

    Pedro Machado · Nottingham Trent University

    It depends on what you want to do. If is a simple application then you should use uC. FPGAs allow you to have flexibility to implement almost any equation however they are more expensive than uC or DSPs.

  • How can one assess the degree of nicotine dependence among e-cigarettes users?

    Does it make sense to use biomarkers such as carbon monoxide and questionnaires (such as the Fagerström) in order to assess the degree of nicotine dependence among e-cigarettes users?

    Vicent Balanzá Martínez · University of Valencia

    Merci bien! I think the Penn State University questionnaire is a wonderful addition to the field. Very helpful indeed!  

  • Craig Dremann added an answer in Political Action:
    Climate mitigation action?
    What must happen for people to reduce and remove greenhouse gases from our atmosphere?
    Craig Dremann · The Reveg Edge

    Writing from a California perspective with the most severe drought in European occupation history--Our State plus Australia, India, Pakistan, and the Kingdom of Saudi Arabia have already entered a climate Armageddon of sorts, in that our rainfall patterns have radically changed, in a similar way as what happened to the Indus Valley civilization 4,000 years ago.    

    You get very scared when there stops being enough rainfall to continue to live in the lifestyle you have grown accustomed to, for the past hundred to thousands of years.

    This change is not going to happen to everyone all at once planet-wide, but will sneak up on those already living on the climatic edges, like arid areas first.

     We cannot expect to pull on the levers of the planet, like adding massive amounts of CO2 each year, cut down and burn the tropical forest host trees of the Pseudomas bacteria, allow our sheep and cattle turn a billion acres of grasslands into desert, cause those desert soils to get airborne which stop the formation of rain clouds, damming rivers and relocating that fresh water out of its original flow-patterns, etc.--and then expect that the weather patterns we need for our human survival to stay the same?

  • Arina Rezaei asked a question in EDTA:
    PBS/ PBS+EDTA for phage detachment?

    Hi everybody, I want to use PBS and PBS/EDTA for phage detachment. What concentration do you recommend If I want to use PBS and PBS/EDTA (separately). There are a lot of variations.

  • Nguyen Hue asked a question in Soil:
    What parameters should be considered when evaluating soil quality?

    Soil quality can be many things to different people. However,should  certain metrics (e.g., soil CEC, microbial population and diversity/activity, soil aeration, bulk density) be included as core parameters when soil quality is evaluated?

  • How to design a hanging mezzanin?

    In order to make more useful spaces in structure, "hanging mezzanine" concept has been adopted, in which the mid-storey is supported from the top floor. can anybody help me in the design process?

    Richard Perry Kulczak · University of Brighton

    Have a look at the Berlin Stock Exchange, or Ludwig Erhard Haus IHK, by Nicholas Grimshaw and Partners (aka Grimshaw). We used a series of multi-storey steel arches from which to hang each concrete floor plate (with  integrated coffered downstand beams) from first floor upwards (like mezannines) to allow for an entirely column-free trading floor at the ground level. It's colloquially called 'the armadillo' and was groundbreaking design at the time.

  • Helios De Rosario added an answer in Motion Capture:
    Where can I find references about dynamic analysis of human body segment shapes?

    I'm looking for a bibliography about how body segments change their outer shape in motion. Trying the obvious keywords in different search engines and scientific databases basically lead me to works about (a) markerless motion capture, (b) analysis of silhouettes, and (c) face morphing. I'm more interested in the shape of other parts like upper or lower limbs.

    Helios De Rosario · Polytechnical University of Valencia

    Thanks Matteo, but what I am looking for are references about characterisation of body shapes in motion, whereas the problem addressed in papers like the one you cite is rather the opposite: how to cancel the motion of such soft structures to estimate the rigid motion of the underlying bones. Of course, one of the strategies for that is trying to model the motion of the muscles and skin, but that is not the focus.

  • Bobby Chaudhuri added an answer in Social Systems:
    Are scale-invariant properties sufficient in determining the degree of resilience of a social system?

    Scale-invariance is often related to features of a network that tend to retain its original properties regardless of scaling (i.e.towards a larger or smaller network).  I am wondering whether such properties, when they exists in a network (in mathematical terms, graphs), may be used as "estimators"/indicators of the system's degree of resilience. I am thinking about resilience in a social context. Taking a systems approach to consider the level of resilience. As for instance in the case of social networks. Although I recognize that it was initially developed for ecological applications. Yet the social sciences in an attempt to borrow ideas from ecology have  increasingly referred to aspects of society as an "ecosystem". So I am concern about sufficiency in the sense of the criteria:"necessary and sufficient" or "necessary but not sufficient."

    The 1999 article by Barabasi and Albert would be the one get as already suggested

  • Breanna Symmes added an answer in Gene Expression:
    Does anyone know where we can obtain fresh MN9D cells? Are they commercially available anywhere?

    Our lab is looking to replace our MN9D cell stocks with fresh stocks, but I have been unable to find out if they are commercially available. Does anyone know of a place we can purchase fresh cells?

    Breanna Symmes · University of Colorado

    Thank you. That is pretty much the conclusion I have come to, as well.

  • Ken Toyama added an answer in Comparative Analysis:
    Which wave guide is better Rectangular or Circular ??


    Please see above.

    Ken Toyama · Juniper Networks, Inc.

    Tamara V. Tulaikova is wrong. There is no inherent loss just because the waveguide cross section is not circular. It is just we can not solve the Maxwell's equation in a closed form solution other than circular cross section. But nature does not care about our inability to solve this mathematically and light can still propagate without loss in a waveguide with non-circular cross section.

  • Philippe Puech added an answer in Radiology:
    Do you know a free Dicom Viewer that allows for freely rotatable 3D MPR?
    I need a free dicom viewer that allows to view a dicom dataset with freely rotatable planes (not only axial, sagital and coronal). I am sure OsiriX can do this, but I don't have a Mac. I found Onis Viewer, this app will do the job but it is not very user friendly. I am looking for something similar to the 3D MPR tool that you can find on Siemens CT Scanners.
    Philippe Puech · Centre Hospitalier Régional Universitaire de Lille

    Maybe you can try Synedra Personal View. It's a great free DICOM viewer with MPR

  • Louis Brassard added an answer in Higher Education:
    Are platforms of professional activity such as ResearchGate appreciated by peers and groups that are not directly involved ?
    For university-based staff, professional/academic activity often features as one of the areas in our appraisals. Some are actively engaged (they attend conferences, network, engage in platforms such as RG etc.), and some simply 'do their job' - teach, research, publish etc.

    1. How important is it to interact with peers outside your institution?
    2. How can we evaluate the 'usefulness' or 'impact' of such activity?
    3. How is such activity appreciated and rewarded?


    Remember that RG has not said what the RG score is actually measuring.  And if you look up for Nobel price winner here on RG you will find that some of them has scores less than 40.