Q&A

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  • Can anyone suggest a good questionnaire to assess mental health knowledge/literacy and/or attitudes?
    Needs to be fairly short and accessible. Preferably relating to MH in children but that's not essential.
  • Is sugar over consumption the underlying cause of the obesity epidemic?
    The current obesity paradigm is basically behavioural; overeating and under exercising as the cause of obesity. Both true but neither has explanatory power unless people deliberately set out to become obese. A single underlying cause is the over consumption of sugars. It fits the descriptive epidemiology: pandemic, both genders, all ages, increasing since the 80's, high prevalence. It fits the biochemistry as causing insulin resistance via glucose consumption stimulates appetite and reduces exercise. It fits the epidemic of Non Alcoholic Fatty liver Disease through fructose. This model supports both individual and public health responses: low sugars diets and low sugars food availability. It also supports recent observational studies and meta-analyses that fats are part of the solution, not part of the problem. Until the paradigm shifts back to the pre-50's diets, we will continue to do the ineffective, calorie restricted diets and increasing exercise, instead of decreasing sugars intake both as individual interventions and public health policy.
    Claudia Strauss · Queen Mary, University of London
    William- the bodpod was wrong, trust me on this one. Max- you said "I just realized that we are talking different populations". This is my grief with the current focus of US scientists in regards to obesity and fructose consumption. They see the US intake and assume: " Heureka, it must be fructose". But they fail to see beyond borders and the exploding obesity levels there. In countries which have negliable fructose consumption. They want to find the one and only culprit. And unfortunatly they become too narrow minded and waste exceedingly valuable brain capacity. In fact, I hardly bother anymore (beyond adding yet another piece of the puzzle) with US research in the sugar angle.
  • Does anyone have experience with the Akta Start?
    It seems that it can do the same purifications as the higher end Akta Purifier/Pure/Avant, it's just that the pumps are peristaltic instead of piston based, but the price is much better!
    James Errey · Heptares Therapeutics
    HI as far as I can see the start is a replacement for the Prime. We still use our old prime for basic work such as NTA or other affinity purifications. The problem with the Prime and the start is that they have a max pressure of 0.5MPa so they will not be able to be use with high resolution columns that run at 1MPa such as a MonoQ or a S200 10/300. This is a good basic system for simple purification it still has the carousel-type fraction collector which I don’t really like as they can miss tubes and end your run but for the price this is a good system but you will be limited with the type of purifications you can run....
  • Hanno Krieger added an answer in Economic Growth
    Is there a negative correlation between population growth and economic prosperity?
    The relationship between population growth and economic prosperity has recently generated a number of empirical studies with conflicting views. While some researchers admit that population growth drains natural resources and slows down economic growth especially in the developing world. Others indicate that population growth might trigger economic growth and enhance economic prosperity. The Malthusian school subscribes to the first view on the negative correlation between economic growth and population increase. Moreover, Malthus expected that the world would witness famine, and shortages in food supplies based on a mathematical view relating to population and food growth processes. However, a group of development economists assert that population growth will increase the stock of human capital, and will definitely lead to economic growth and development. Therefore, what is your input on the relationship between economic growth and population increase? Is the relationship a negative or a positive one?
    Hanno Krieger · Justus-Liebig-Universität Gießen
    Dear András, good tip, but I don´t have precise numbers, just the raw infos from TV and press. So if you are right with your supposal, you will find trends for the future developments. Regards
  • Could EFL/ESL learning in the Cloud classroom happen without teachers?
    It may be said that face-to-face teaching is the best method for EFL/ESL or foreign language learning. Do you believe that the Cloud concept is changing the future for face-to-face teaching and learning?
  • Sinker stones, net sinkers, or weights - any thoughts?
    Need help for examples of prehistoric grooved, notched, waisted and coffee bean shaped weights (net sinker) attested to the Neolithic or Chalcolithic period from Aegean Basin and Anatolia. See attachment for sample pic.
    Paolo Biagi · Università Ca' Foscari Venezia
    I will try to look at samples from Poliochni for instance. In the Arabian sea these are very common anyway PB
  • Farukh Farukh added an answer in Abaqus
    What is wrong with the STRESS values in UDMGINI user subroutine in Abaqus?
    I wrote a subroutine UDMGINI to define a damage initiation criterion, but I found that the variables of stress were very strange. I kept track of stress (NTENS) using the state variables STATEV, and I was surprised to find that the STATEV didn't correspond to the output variables S (the 6 composants respectively). Has someone ever encountered this problem? Thank you very much. If someone wants to communicate with me about the XFEM in Abaqus, I will be very happy.
    Farukh Farukh · Loughborough University
    Thanks for your prompt reply. I have tried all these including Hard for PRESSURE-OVERCLOSURE but the error is same. Do you have any idea how to get rid of it? FF
  • Raul Perez-Lopez added an answer in Earthquake
    Can rain be a factor of generating a moderate (M > 5) earthquake at a depth of > 10 km?
    .
    Raul Perez-Lopez · Instituto Geológico y Minero de España
    Well, that question is now wandering here in Spain in some earthquake clusterings, what is the role of the heavy rains as the triggering mechanism for shallow (d<4 km) and small-sized earthquakes (M<2, approx.)?. Different scientists have performed a correlation for the time series between swarms and rains and surpisingly, the analysis suggests the opposite, earthquakes triggering heavy rains!!!!. Obviously it is nonsense. Theoretical basis could supports that heavy rains trigger small very shallow earthquakes, but empirical data does not, till now.
  • Phillip P. Sharp added an answer in LC-MS
    Any one who can help me supply Rheic acid (high purity) in the shortest time possible?
    In need of high purity Rheic acid as a reference.
    Phillip Sharp · The Walter and Eliza Hall Institute of Medical Research
    Rheic acid (Rhein) is commercially available. Should ship in about a week or two from AK scientific ~$ 100 per 100 mg (http://www.aksci.com/item_detail.php?cat=67432). Also available from other suppliers like Aldrich.
  • Is flip teaching the new revolution in education that will enhance student performance?
    Flip teaching, reverse teaching, backwards classroom, flipped classroom, and reverse instruction is a new method in teaching where students work online by watching video presentations or video lectures at home, and come to class to discuss a new content, ask questions, interact with other students under the personalized guidance of instructors who are now on the side, instead of lecturing for hours and hours as in the traditional way of teaching. Flip teaching,or the Thayer method renders instructors as peers to students that listen, watch, and guide or advise contrary to being the only talking heads in the class. This method is intended to make students better learners and enhance their personality and academic performance. Flip teaching grants students more control, and furnish the grounds with more student collaboration and interaction, and could be considered the ideal model of teaching and learning. However, some educators consider flip teaching as counterproductive due to the fact that it relies on students to do their work at home i.e., watching video lectures, and accessing academic works where there is no way to guarantee that. Thus, what is your input on flip teaching? Do you use flip teaching at your academic institution?
  • Iain Lawrie added an answer in Healthcare Quality
    Do you think that patient-physician e-mail can increase health care delivery?
    Patient-physician e-mail: an opportunity to transform health care delivery.
    Iain Lawrie · Pennine Acute Hospitals NHS Trust
    I think they'll augment the process, and prove useful in terms of reminders and health messages, but might not be best placed for meaningful diagnostic or therapeutic interactions.
  • Iain Lawrie added an answer in Academic
    ًًWhat do you think about recommendation letters?
    Are hey crucial? Do they represent reality?
    Iain Lawrie · Pennine Acute Hospitals NHS Trust
    I think they are an important part of the process, but maybe not crucial. Often, it's what the letters DON'T say that is more telling!
  • Why do we modulate a signal during transmission and demodulation during receiving? Why don't we send a signal directly without modulation?
    What is the purpose of doing this?
    Vasile Surducan · National Institute for Research and Development of Isotopic and Molecular Technologies
    Perhaps the simplest explanation is given by the TV remote control. The IR signal is modulated on 38KHz (36KHz to 40KHz). By pushing a button you get a digital code. The code is modulating the IR, so there is lower interference with the ambient light, higher distance and no direct visibility between transmitter and receiver is even required. If you really want, you can transmit the digital code without modulation to your TV, but will be painful. You'll have to stay cringed at 2m in front of your TV with your remote control perpendicularly on you TV screen, and with the curtains drawn... :) Now, replace the IR with the RF and you get the proper answer. However modulation is painful, you may have ZIF (zero IF) modulation, superheterodyne modulation (fixed intermediate frequency) or many others.
  • Mounted sections floating off during counterstain?
    This morning I was counterstaining some slides, and was horrified to see my carefully mounted sections floating away in the first tap water wash! I've never seen this before so was wondering if anyone had any suggestion on why it happened. Details: 50um rat brain sections, DAB staining, mounted on standard twin-frosted slides using 0.2% gelatin in PB The sections were left to air dry for a lot longer than usual before the counterstaining... this is the only thing I can think of that could have caused it, but I find it unlikely - surely longer dry times would more securely bond the sections to the slide? Any thoughts would be great!
    Prabhakar Kumar · Mathura University
    We use gelatin
  • Is it still ABC or now CAB in resuscitation?
    Current recommendation says CAB as the correct sequence of resuscitation, although many are reluctant to do away from ABC.
    Niroshan Sivathasan · Australia
    No; to my knowledge, in both Australia and Britain, the standard remains A, B, C, i.e. airway with C-spine protection, breathing, and circulation. Naturally, the art of good medical practice involves deviation from guidelines, but when in stressful moments, and in terms of uniformity and communication for the team (= multidisciplinary, by definition), sticking with 'A, B, C' is the safest.
  • What do you think about the efficiency of webGIS in drought monitoring and management?
    With agriculture and hydrological drought approach.
    Hazhir Karimi · Isfahan University of Technology
    Dear Behroz , I think it is better use RS for monitoring,but before that you must structure a hierarchy for your goal within Multi Criteria Decision Analysis(MCDA). MCDA is powerful mean which focus on effective factor on drout
  • Iain Lawrie added an answer in Education Research
    Should research ethics, institutional ethics and professional ethics be taught to UG and PG students as a course in all subjects?
    Should research ethics, institutional ethics and professional ethics be taught to UG and PG students as a course in all subjects?
    Iain Lawrie · Pennine Acute Hospitals NHS Trust
    I think that they should all definitely be taught, but whether they are part of a specific course, or embedded as a recurring theme throughout all aspects of training, should be considered. I think there may be more relevance and meaning for learners if they are woven into the course as a whole.
  • How can I prevent peak tailing in HPLC?
    I am using acetonitrile and water as a mobile system and C18 column for separation of some drugs, but the obtained peaks were broad and tailed. How can I improve the shape of these peaks?
    Panikumar Anumolu · Gokaraju Rangaraju College of Pharmacy
    Peak tailing due to The flow-line contains extra dead volume Some basic or chelating compounds show singular tendency to adsorb to stationary phase (Remedy: suppress absorbance by adjusting the separation conditions, such as mobile phase pH, etc.) Sample overloading Silica-based column degraded at high pH or high temperature hope this may help
  • Patrick Solé added an answer in Development
    Which branch of mathematics is developing faster than the others?
    Some fields are new, some become old. To start research and be successful, it is crucially important how fast you can get there.
    Patrick Solé · Institut Mines-Télécom
    So if theory X is the winner you are going to convert to the true faith and jump in the bandwagon?
  • What liquid is needed to store an organ that will be analyzed with immunohistochemistry?
    I want to do immunohistochemistry on an aorta. I want to store in 70 °C, but the 70 °C refrigerator is full, so I think I need to store in a liquid, but I don't know what liquid to use. My friend told me to use PBS, another told me to use the buffer formalin. Thanks for your help.
    Prabhakar Kumar · Mathura University
    You can store part of the organ in fixative
  • What is the best medium for MEF feeder culture?
    Which protocol or medium should be used to improve the adherence of the MEF cells? I bought irradiated Mouse Embryonic Stem cell (iMEF) from Globalstem, after thawing 2 vials of the cells 2 min in the 37 degree (incubator) and washing with fresh medium, we used two protocol for culturing them in the 25 cm2 flasks; 1- DMEM/F12 supplemented with 10% FBS (not inactivated), L-glutamin and Pen-strep 2- DMEM/F12 supplemented with 20% knockout serum (not inactivated) suitable for ESC and IPS cells, L-glutamine and Pen-strep, After 24 hours, in the first way cells attached so low and in the second way no cells attached. I checked viability of cells before culturing and all of the cells was alive.
    Katharina Klich · Max Planck Institute for Molecular Biomedicine
    It's DMEM without F12 and we had also both irradiated MEFs and now use mitomycin inactivated ones. Both look/looked happy...
  • Khaled Z added an answer in Hematology
    What is responsible for the prolongation of Prothrombin time and Activated partial thromboplastin time tests in a stable sickle cell patient?
    Stable in the sense of being free from crisis.
    Khaled Z · Centre Hopitalier Antibes Juan-Les-Pins
    Hello, What do you mean by "stable". Need also to know the results of prolongation. It still a hemolyical anemia anyways...
  • As a researcher, what makes you choose a particular journal to publish your articles?
    Currently, there are more and more journals in almost all areas. Some offer restricted access, others offer open access. Some charge for publication, others charge only by open access option. What sets your choice?
    Bassam Al-Naami · Hashemite University
    I think the "EBSCOhost: Applied Science & Technology Source" is very strong and professional index. Adapted/ approved it at Jordanian universities would be very helpful.
  • What are that white bands in my western blot?
    Hi to all. In my last experiment was happened such a puzzling thing: I performed an electrophoresis (using a 4-20% TGS PAA gel) on samples containing Both a ~30 bp DNA duplex and a recombinant protein expected to bind. Once I transferred the gel on a PVDF membrane and done a western blot against the specific protein, i saw the expected black bands of my protein in the region of low molecular weights, but in the region of high molecular weights, in correspondence of the lanes where the 30 bp dNA duplex was loaded, there were 3 bands negatively colored: they were white, while the protein bands, as expected were black. Afterwards I stained with Coomassie stain my membrane and as expected my protein was not stained, but that three bands that appeared white after the western blot, yes: they were of a fantastic blue. What were that three negatively coloured three bands in the western-blot step? Is it possible that the three bands were DNA and coomassie staining was able to stain them? Were they a putative DNA complex with my protein that having modified is charge interacted with Coomassie? how can I explain these facts? Thank you
    Antonio Rosato · Università degli Studi di Bari Aldo Moro
    ok, but in this membrane, as I've written, I have both black bands in the region of low molecular weights (as I expected), but in the lane where I added the DNA I have both the black bands in the low molecular weights region, and I see one and in each lane in the high molecular weights region that are white! what does it means? in each lane I've loaded the SAME quantity of protein, so what would it means a highly saturated detection???
  • Bernard H Casey added an answer in State
    Is caring for pensioners (retirees) a state responsibility or a personal responsibility?
    Pensioners served their country and people for many years. Who should take care of them? Do they need to plan their retirement on their own, or should the government take care of them?
    Bernard Casey · The University of Warwick
    see the letter to the Financial Times attached
  • Can anyone suggest NGS sequencing services in India?
    I am interested in WGS of some 500 rice genotypes. Can anyone suggest a service provider who can provide quality data quickly under a competitive price.
    Jude Fernandes · Karolinska Institutet
    You can also look up Genotypic (Bangalore), they have an agri division also. Another is SciGenome (Cochin). They are quite prompt with their service.
  • What is the best way to separate human granulocytes from whole blood or buffy-coat? How long can neutrophils survive in culture media?
    Neutrophil purification
    Binnur Tüzün · International kolan hospital
    Thanks beatrice