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  • Yong-Pil Cheon added an answer in Conventional PCR:
    Why do cells keep dying after two passages even if ther's no mycoplasma contamination?

    I am working on mouse embryonic stem cells (R1) and have been facing a lot of problems of late in its culture. After reviving, the cells grow fine on feeders for about 2passages. In the third passage, they start dying off, their morphology looks like apoptosized cells, colonies disintegrate and a lot of debris is formed in the media. I have checked for mycoplasma but the test results came negative.

    I grow the cells in high glucose DMEM supplemented with 15%FBS, 1%NEAA, 0.1%Beta-mercaptoethanol, L-gulatmine and LIF. This behavior has been quite consistent and I have also tried with different batches of cells. Can anyone figure out what might be going wrong? Moreover, its only the ES cells are dying off; underlying MEF feeders seem fine. Ther's also no visible contamination.

    Is there any strain of mycoplasma that is not detected by the conventional PCR test kits?

    Yong-Pil Cheon · Sungshin Women's University

    please check your incubation condition such as incubator or osmosis etc.

  • Kamal Eddin Bani-Hani added an answer in Philosophy:
    Can ethics be measured objectively?
    Ethics, ethical committee, ethical approval and other ethical related words are extensively used on Researchgate and other places. How to define and measure ethics in objective bases?
    Kamal Eddin Bani-Hani · Hashemite University

    Khwārizmī Equation for ethics:

    If you have ethics your value is = 1

    If you have also beauty then add a zero, and your value will be = 10

    If you have also money, then add another zero, and your value will be = 100

    If you have also power and strong family, then add another zero, and you value will be = 1000

    Now: If your ethics disappear (1), then your value will be either (0) or (00) or (000) = Zero

  • How do you feel about the state of architectural education today?
    Are universities doing a disservice to their architecture students by focusing on design vs the Master Builder Architect focus? I have heard from many architecture professors that many schools are focusing on design more without much focus on students' comprehension of construction.
    Wanita Subadra Abioso · Bandung Institute of Technology

    Actually there are many architectural higher educations which focus on both "Architectural Design" and "Construction" including in my institution. But we frequently encounter the problem of superimposing both design and its construction, since "the so called paper architecture" as mentioned above by Luis Inostroza usually avoiding the reasonable construction for the sake of name it "venustas"(beauty) or art. I've been involved in some constructions of designed building, and it's really time consuming in synchronizing the design with its construction if we didn't consider the construction in the first place. Seems we have to reconsider what has been formulated by Benjamin Handler concerning "System Approach to Architecture". We have to design and consider the architectural design, the construction, maintenance and repair, and human behavior if it possible the end of usage of the building, simultaneously in the DESIGN STAGE, it's could be called a cradle - to - grave design.

  • Shailesh Yagnik added an answer in Library Science:
    Is there any good instrument on how to measure reading habits?

    Most student in library science field came up with such question.

    Shailesh Yagnik · Mudra Institute of Communications, Ahmedabad (MICA)

    Pl. find out the survey conducted on readership survey in your country.

  • Luis Jose Fernández added an answer in Biogas:
    Can anyone suggest method to agitate slurry inside Biogas digester to stimulate bacterial activity avoiding both gas leaks & outside air enterance ?

    Capacity of plant is around 2-3 m3 . After critical survey on the literature I found there is lack of ideas and suggestions on agitation of slurry inside  such mid-size digester (6-8 feet) .Many of Methods encountered on internet are practically not feasible. I request researchers to suggest for the the same.

    Thanking you.

    Luis Jose Fernández · Universidad Nacional del Litoral

    I would try storing a volume of the same biogas and  pulse  injecting it down the slurry

  • Timur Islamoglu added an answer in Materials Studio:
    How can one create a geometry for solid solution (substitutional) in Materials Studio?

    What is the best way for create the geometry of a solid solution (for example Mg-3%Al) in Materials Studio to calculate work function?

    The way that I can imagine should be like this:

    Creating one unit cell of initial elements (e.g. Mg-HCP) and then adding some more cells. Then changing some elements (Mg to Al). But  I didn't succeed to do it because:

    1- I couldn't add more other cells to the first unit cell (Crystal).

    2- I couldn't change only one atom of a unit cell. all atoms will be changed because of symmetry.

    Thank you so much.

    Timur Islamoglu · Virginia Commonwealth University

    I think your second approach makes more sense. After you have created your Mg network you should convert symmetry to P1 which will consider your unit cell as a molecule instead of an extended network. Then you can replace some of your Mg with Al. But you cannot apply actual symmetry again because it will make the same problem. However you can minimize the energy of the structure and do calculations with P1 symmetry as well. Since it is a your unit cell, you still can expand it in 3D by adding more unit cells from Display options. 

    I hope it helps.

    Thank you,


  • Madhavi Vaidya asked a question in MapReduce:
    Has anybody worked on iterative MapReduce algorithms/functions? If yes, in context with which use case, please provide and how?

    MapReduce, Large Data Analysis

  • Helena Amaro added an answer in Institutions:
    Should medical practitioners/institutions be held responsible for fatal lapses in treatment?

    Should such lapses be viewed seriously

  • Sardar Asad Ali Biabani added an answer in Profit:
    Can reinvestment of profits be a solution to business growth?

    Growth has been a major concern in recent years, especially in the context of the current crisis. Yet diverse solutions and recommendations have been tried. Reinvestment is rarely discussed as a viable solution to companies growth, though is had yielded significant growth in some developing countries. What are your kind opinions and views on this issue?

    Sardar Asad Ali Biabani · Umm Al-Qura University

    Considerably, it bears both the positives and negatives. Is it going to be sustainable? Is it fully profitable? In what time-frame can you achieve this growth? And more importantly, it depends on many outside factors like the current market demand & value of commercial enterprise in which you are reinvesting it.

  • Is there any software by which we could attach two domains via a 24 AA in Gly rich linker?

    I am looking for an approach and or tool/software by which I could link one protein domain to another protein domain via linker (24AA and Gly rich linker)?

    Thank you

    Jonathan Elegheert · University of Oxford

    Hello Navaneet, I would just use Coot for this particular problem. Coot is crystallographic software to build macromolecular models into electron density, but can be used flexibly to do a variety of model manipulations as well, such as the linkage you require.


    Hope this helps,


  • Is there any new software for simulation of wastewater treatment plant?

    new software like GPS-X for wastewater treatment plant

    Raul Muñoz · Universidad de Valladolid

    Biowin is a cost-effective program.. and WEST if you can more flexibility and computational power.

  • Abhijit N Kadam added an answer in Particle Size:
    What is the difference between grain size and particles size?

    is there any difference between particle and grain?

    Abhijit N Kadam · Shivaji University, Kolhapur


    Luiza Dihoru ·

    Thank you very much for sharing your valuable knowledge 

  • Raul Muñoz added an answer in Water Treatment:
    What kind of process carried out in water treatment plant using Bioreactors?

    I need an protocol for treating wastewater sample in Airlift Bioreactor using natural adsorbent materials  like banana peel, algae and some other materials?

    Raul Muñoz · Universidad de Valladolid

    My main concert is why to use bioreactor if the process you intend to develop is based on physical/chemical mechanisms. There is plenty of literature on airlift bioreactor 

    For an updated review check: Guieysse B, Quijano G, Muñoz R (2012). Bioreactors – Design | Airlift Bioreactors. In: Comprehensive Biotechnology, Second Edition. Edited by: Murray Moo-Young, volume 2, pp. 199–212. Elsevier. ISBN: 978-0-444-53352-4. 

  • Has there been research to showing that increasing education improves ethics in a community?

    'Students often know the right thing to do. How can schools help them to do it?

    The numbers are in and they don't look good." That was the assessment of the Josephson Institute of Ethics last October, when they conducted a survey about the moral standards of more than 20,000 middle and high school students. Almost half the young people reported stealing something from a store in the previous 12 months. In the same period, seven out of 10 cheated on an exam.
    Should we be worried? Many observers say that we should. We see evidence of more antisocial behavior than ever among our youth—a sort of divorce between personal ethics and everyday behavior.'

    Has there been research to show that with increasing education, there has been improved ethics in a community?  Can you share, give some evidence? Thanks.

    Kamal Eddin Bani-Hani · Hashemite University

    Khwārizmī Equation for ethics:

    If you have ethics your value is = 1

    If you have also beauty then add a zero, and your value will be = 10

    If you have also money, then add another zero, and your value will be = 100

    If you have also power and strong family, then add another zero, and you value will be = 1000

    Now: If your ethics disappear (1), then your value will be either (0) or (00) or (000) = Zero

  • Paul M.W. Hackett added an answer in Genotyping:
    Can you suggest authors who have summarised Conrad Waddington's work on the Strategy of the Genes?

    I am looking for authors who have written about Conrad Waddington's Strategy of the Genes and his view about genotype/phenotype relationships. Can anybody suggest both elementary reviews of his work and also research that has taken this forward?

    Paul M.W. Hackett · Emerson College

    Thanks Nills

  • What are the semi-empirical Bethe-Weizsäcker mass formula limits ?

    can this formula be applied to exotic and close shell nuclei. 

    E.D. Mshelia · University of Maiduguri

    The Bethe-Weizsaecker semi-empirical mass formula is essentially based on the liquid drop model (LDM) of the nucleus where the surface is sharply defined, has a constant internal density  and a  latent heat of vapourization  proportional to the density. The main contribution to the binding energy comes from the volume energy term arising from the  short- range nature of nuclear forces leading to their saturation. The LDM   is not valid for nuclei with very small mass number values below A =12 where the surfaces can be considered as diffuse. The LDM is a classical model. Quantum mechanical properties manifested in the asymmetry energy term, pairing and shell structure effects do not contribute much to the overall binding energy per nucleon. In this way the Bethe- Weizsaecker formula is capable of reproducing the gross properties of over 200 medium-heavy and heavy stable and unstable nuclei, particularly the energy released in nuclear fission.

  • Steven Reiss added an answer in Psychology:
    What is the fragmented self?

    I was searching for the definition on google and I found articles related to dissociative disorder. Does that mean fragmented self?

    Steven Reiss · The Ohio State University

    Even in psychoanalysis I doubt if it is a generally defined term

  • Arjun Datt Law added an answer in Acute Leukemia:
    What is the optimal induction regimen for patients with biphenotypic acute leukemia?

    What is the optimal induction regimen for patients with biphenotypic acute leukemia? Should they be treated with AML-type or ALL-type induction regimens?

    Arjun Datt Law · Postgraduate Institute of Medical Education and Research

    Most data available at present advocate an intensive ALL type regimen (Such as Hyper CVAD or St Jude Total XIII-B) with early transplant. Needless to say, a suitable TKI should be added if a Philadelphia chromosome is associated. 

  • Mohamed El-Begermy added an answer in Laser Surgery:
    What are your experiences with Trans oral LASER surgery for early laryngeal cancers?

    We are working on introducing the procedure in our hospital, your experiences will help us start successfully. Thank you all

    Mohamed El-Begermy · Ain Shams University

    the result of LASER therapy in laryngeal cancer is excellent  and comparable with other modalities like radiotherpy or  chordectomy It has the advantage of avoiding external incisions rapid ambulance overall less cost .. However if it is not available in developing countries -- radiofrequence  or chordectomy through laryngo-fissure is an alternative 

  • Jharna Mandal added an answer in Algae:
    Recently i am growing algae in petri dish..during growth i found fungus or yeast..why? I used BG 11 media..should i use antibiotic?what to do ?

    plz suggest solution for preventing growth of yeast or fungus ?or other relative precaution for making BG 11 medium.thanks

    Jharna Mandal · Jawaharlal Institute of Postgraduate Medical Education & Research

    You can try an axenic medium with antifungals incorporated.Also I would suggest that you use test tubes(wide mouth with screw capped) rather than petriplates,this would bring down your contamination rate.

  • Anup Lahiry added an answer:
    Isotretinoin for acne vulgaris?
    Can isotretinoin be given in pulse mode for moderate and severe acne? How frequent are lipid abnormalities seen with short and long term use of isotretinoin?
    Anup Lahiry · Apollo Hospitals,Secunderabad

    I prefer to use either step up or step down dosing of Isotretinoin,the end point being the total cumulative dose of 150-160/mg per Kg of body weight.Even if we give pulse dose response will take a longer time and patient compliance goes down.

  • Energy conservation feedback?


    Hope you are well.
    I am writing a journal paper on spreading energy conservation awareness using the power of social networking.

    I would really appreciate if you could spare a minute to fill a survey for my research. This is crucial for completion of my paper and hence I have included only few important questions which shouldn’t take more than a minute to complete.

    Please follow the link to the survey:
    SURVEY URL: https://www.surveymonkey.com/s/8LYRG5M

    I would be great if you can forward it to your office colleagues and friends too as this would be of immense help to me and all individual responses will be kept confidential.

    Hope to receive a positive response from you. Thanks in advance!!
    Wish you a Merry Christmas and a Happy New Year!
    Amruta Nayak
    MS in Industrial Engineering
    University at Buffalo, the State University of New York

    Ali F. Alajmi · Public Authority for Applied Education and Training

    I completed the survey. Good Luck

  • Hozeifa Mohamed Hassan added an answer in ALP:
    What is the cause of a high level of alkaline phosphatase (ALP) in hepatotoxic-induced animal models?

    I'm keep getting higher ALP serum levels in the control, untreated group compared to the treated ones, is there is any explanation for this?


    Hozeifa Mohamed Hassan · China Pharmaceutical University

    Hi Seyyed

    I understand your point, but it is clear that hepatotoxicity was confirmed by measuring the blood biochemical indicators as I mentioned earlier, and by default, toxicity will results in changing on the all animal behavior (including other factors beside feed intake), and we use the enzyme analysis for confirmation of this toxicity. At the end, I'm searching for a scientific justification on the situation that mentioned in the question. I hope you get my point

    Thanks for passing :) 

  • Hongwu Jing added an answer in Angiotensin:
    Can someone suggest a possible Protocol to extract Angiotensin peptide from Blood?

    I Want to extract Angiotensin peptide from blood, already i have synthesized biologically active Angiotensin with higher purity, Now i want to extract natural peptide and compare the biological properties of both, Am looking perfect procedure from Experts.,

    Hongwu Jing · The Ohio State University

    See if this paper can help


  • What is meant by setpoint and integral gain in scanning probe microscopy?

    Setpoint and Integral gain seems to be vital parameters that control the scanning of the sample surface during scanning probe microscopy. How do these parameters control the final image characteristics?

    Abhinav Varshney · Indian Institute of Technology Kanpur

    Thankyou very much Rebis for your valuable input. I am trying  to perform scanning probe microscopy (SPM) on a high carbon multiphase steel. Since phases formed are few microns in size, to get the hardness of  the individual phases, I am performing nanoindenation (NI) after getting the image from SPM on a Hysitron nanomechanical system. For NI, Berchovich tip is being employed.  Since the image that we are getting in not a high quality image we are stuck as we can't differentiate the individual phases. 

  • Can someone advise me about Panel data after PSM?

    Although I am not actually carrying out panel data after PSM, I'm exploring its possibility. I do have matched data after propensity score matching. But my point is: if I obtain matched data for each year and then merge the data (such that the data contains both person identification as well as time i.e. years), how can I carry panel data analysis? Should I control only for propensity scores or should I include other variables as in the case of regression adjustment? My doubt is: since the variables are already matched, would it still be possible to carry out panel data analysis including all the required variables or not?

    Jonathan Wood · Pennsylvania State University

    The short answer: yes you can.  Just make sure that you match individuals (all years) rather than yearly observations for each individual.  Also, it is best to only match on pre-treatment characteristics, if possible.

  • Ajay Singh 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?
    Ajay Singh · IIT Kharagpur

    The caste employment is a part of our system everywhere without any exception. Favor, groupism, corruption, and nepotism in recruitment/promotion are the various types of a caste employment.  Regarding the law, I am very much sure that no country has such a law which supports these malpractices in recruitment and promotions. 

  • Narasim Ramesh added an answer in Imaging:
    Can somebody recommend references on the technique for imaging of the occluded objects?

    I am mainly interested in the understanding the techniques used for this and in algorithms for recovering the occluded objects from the acquired data. Can somebody recommend relevant references? Thank you in advance!

    Narasim Ramesh · Sri Jagadguru Chandrasekaranathaswamiji Institute of Technology

    Please see (some wild suggestions below):

    1 A very simple case would be "X"  ie 2 line segments crossing. If included angle theta is>0 then there is only one common cross-over point. We can get this only if we make the assumption of continuity of the segments at the common point.!!

    2.A possible (just a conjecture ) with objects in images is to reduce objects to closed line polygons and use solution of 1(e.g skeletonization). Another possibility is to use fractal geometry of objects in the image.


  • Jaydeep Gajipara added an answer in Abaqus:
    How do I extract results for every load increment not time increment?

    I want to have result for every load. As in abaqus it gives result for every time increment and we can plot results. But I want to plot and have result for every load  increment.

    Jaydeep Gajipara · Nirma University

    thank you ali..can you tell me how to get the output result? i mean in which output file i can get analysis results??