Q&A

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  • Abbas Rahdar asked a question in Thin Films:
    Which deposition method does the oxide thin film is better? why ?

    Which deposition method does the oxide thin film is better? why ?

  • Julio Sanmiguel added an answer in Soil Analysis:
    How can I compare gene abundances when different standards have been used?

    I wish to compare the abundance of the 16S gene in soil samples collected at different times (six-monthly collection). From one set of samples to another, I had to use different standards. The standards were made from different plasmids and have a different concentration, and I am therefore not sure how to compare my results from one sampling time to another. Could using the number of gene copies / ng DNA solve this calibration problem?
    Any suggestion would be welcome!
    Thanks
    Frédérique

    Julio Sanmiguel · University of Pennsylvania

    Hello Frédérique.

    May I ask first what technique you are using to make this comparison possible, please. Did you include a validation reference throughout your analysis? I mean, a sample or two whose abundance you knew in advance. Do you have any of the standards left?

    JS

  • Nick Burns asked a question in Disaster Relief:
    What are some of the most efficient disaster relief shelter solutions that have been used / considered recently?

    what makes them more effective / efficient than others?

  • Ruba Shira added an answer in Panel Data:
    Should one always use panel data analyses methods when running models on longitudinal stock market and other financial statement data?

    Should one ALWAYS use panel data analyses methods (e.g. E-views software) when running models on longitudinal stock market and other financial statement data? Or, can one still apply OLS regression models (as per SPSS software)?

    is there a test which one can run which would indicate that panel data analyses is advised?

    Ruba Shira · Brunel University

    Hi Leana, from my little experience...I would suggest using Panel data models i.e. FE or RE to solve what called "unobserved heterogeneity (individual-specific effects) and omitted time-varying variables". Or, 2SLS, IV or Generalized Method of Moments (GMM) estimators for endogeneity problem but GMM will account for both problems.  Note that use GMM only when the cross-sectional dimension is large and the time-series dimension is relatively small. (Large N, small T)... Good Luck

  • James Leigh added an answer in Innovation:
    What is the most innovative health improving technology you know of?

    Why is it innovative?
    How does it presumably improve health?
    What understanding of health is is grounded on?

    James Leigh · University of Sydney

    Although not really technologies, WHO  Global Risk Factor and Burden of Disease Studies show that prevention of child and maternal malnutrition , abolition of tobacco smoking and control of HIV contribute most to overall global health improvement .

    For technologies,I would vote for antibiotics and CT/NMR imaging as the most significant in the last 100years .

  • Duke Zhang added an answer in Depression:
    Why depression is so common nowadays?
    • Is it because we are in the information age?
    • Why?
    Duke Zhang · Beijing International Studies University

    People will never be negatively emotional, if they are clear about the three questions: where are they from before life here? What's the meaning of living and life? Where will they go after death of the body?  To make sense of the three questions, one need to cultivate in a Buddhist way.  This answer is surely personal, something of my own experience. To know more, some books about reincarnation or previous life may help find a clue to the answer. 

    Let's shift to Freud's and Maslow's theories, one word may be the key: imbalance. Some words more: the imbalance between the physical or mental needs and the shortage.

  • Brandon Ambrose Kemp added an answer in Fenofibrate:
    How i can dilute fenofibrate, a drug which is completely insoluble in water, for intragastric gavage in rats? in oils or...?

    i have a problem with this drug..

    Brandon Ambrose Kemp · University of Virginia

    hello,  I have attached a few links that could help you with your problem.  When we have this problem administering drugs to rats, we use dmso to dissolve the drug and then further dilute this in water to drastically lower the final dmso concentration.  I am not sure rats would like dmso in their stomach but if it was diluted they might not mind it.  Good luck

    http://www.dissolutiontech.com/DTresour/200articles/200art3.html

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3399483/

    http://www.academia.edu/2611991/TECHNIQUES_FOR_SOLUBILITY_ENHANCEMENT_OF_POORLY_SOLUBLE_DRUGS_AN_OVERVIEW

  • Can anyone explain, how to reverse engineer any *.apk file, to view original source code of the app?

    I want to perform reverse engineer on a compiled and running *.apk file, but could not find the right way to do it, can anyone help me to guide.

    Leonard Goeirmanto · Universitas Mercu Buana

    agree with Mr. Han that you can not use Eclipse to decompile, here are some references about reverse engineering in mobile apps:

    DOI: 10.1016/j.cose.2014.10.016

    DOI: 10.1109/DEXA.2012.40

    DOI: 10.1109/WCRE.2011.42

  • G. Bothun added an answer in Galaxy Clusters:
    What is causing Dark Flow?

    Dark flow is an astrophysical term describing a possible non-random component of the peculiar velocity of galaxy clusters. The actual measured velocity is the sum of the velocity predicted by Hubble's Law plus a possible small and unexplained (or dark) velocity flowing in a common direction.

    Does Dark flow exits ? If yes what is the cause of it?

    G. Bothun · University of Oregon

    These are old papers but I think provide a decent basic explanation of this.  Ultimately these flows provide gravity maps of the local universe:

    http://adsabs.harvard.edu/abs/1992ApJ...388..253B

    http://adsabs.harvard.edu/abs/1992ApJ...395..347B

  • Billy Chen added an answer in Zircon:
    Why is activation energy less than 40 kJ/mol is better?

    I find this paper "Torque rheology of zircon feedstocks ..." author J. Hidalgo et al. It says activation energy less than 40 kJ/mol is better. Why 40?

    Billy Chen · National Kaohsiung University of Applied Science

    Thanks for all answers.

    I think the 40kJ/mol activation energy is mean the lower the better.

    Maybe the author just want to say that in other words.

  • Call for Chapters: Handbook of Research on Next-Generation High Performance Computing - IGI Global?

    Researchers and practitioners can submit their papers on this link: http://www.igi-global.com/publish/call-for-papers/call-details/1688

  • What is the intensity of business simulation games in higher education in Spain?

    Business simulation games are widely used in business schools all over the world. However, I find few research publications about it specially from Spain. Who are the key researchers in this field. Business simulation games are part of experiential learning approach to develop higher order skills.

  • Abbas Rahdar asked a question in Cold Plasma:
    What is the difference between hot and cold plasma?For uniform deposition Which is better?

    What is the difference between hot and cold plasma?For uniform deposition Which is better?

  • Richard Yuan added an answer in Modal Analysis:
    Why has ansys workbench given different modal analysis result from mechanical APDL?

    Modal analysis conditions: circular plate fixed at the edge, thickness 0.4um, diameter 800um, material density 2330kg/m3, Young's modulus 1.6e11, poisson's ratio 0.22.

    Workbench gives the 6 modes as:
    1. 9971.5
    2. 20763
    3. 20764
    4. 34074
    5. 34083
    6. 38874
    While mechanical APDL give different modes as:
    1 10189.5
    2 21209.5
    3 21210.3
    4 34792.9
    5 34800.6
    6 39701.0

    Here is my APDL script, can anybody tell me why?

    FINISH
    /CLEAR,NOSTART
    /FILNAME,diaphragm,1
    /TITLE,diaphragm modeling
    /REPLOT
    /PREP7
    !*
    ET,1,SHELL181
    KEYOPT,1,3,2
    SECTYPE,1,SHELL
    SECDATA,4E-7,1,0,3

    MPTEMP,,,,,,,,
    MPTEMP,1,0
    MPDATA,EX,1,,1.6e11
    MPDATA,PRXY,1,,0.22
    MPTEMP,,,,,,,,
    MPTEMP,1,0
    MPDATA,DENS,1,,2.23e3

    CYL4,0,0,4E-4

    LESIZE,ALL,1e-5, , , , , , ,1

    AMESH,ALL
    !*

    /SOLU
    ANTYPE,MODAL
    MODOPT,LANB,6

    DL,ALL,,ALL,0

    SOLVE

    /POST1
    SET,FIRST
    /EFACET,1
    PLNSOL,U,Z,0,1.0

    Richard Yuan · Shanghai Integrated Circuit Research and Development

    Dear Naveen Bhatt,

    Thank you. You really point out a userful direction. I checked the log files carefully and found that the TOTAL MASS given by Workbench is 4.6843E-10, and that given by MAPDL is 4.4832E-10. The TOTAL MASS difference gives a manify factor of about 1.022. That is the rout cause I think.

    Now I have to ask, Why the TOTAL MASS is different at the same geometry?

    Regards

    Richard

  • G. Bothun added an answer in Climate Change Impacts:
    Will climate models based on their performances in reproducing historical climate provide better predictions in the future than other models ?

    In climatic change impact studies, many authors suggest to select climate models based on their performances in simulating present or past climatic conditions to provide better predictions and reduce uncertainty. But how can they be sure about that particularly under non stationary climatic conditions? 

    G. Bothun · University of Oregon

    Yes "weather and climate" on some timescales is a statistical effect and so  mean values and changes probably can be will predicted by the models.

    It this kind of stuff:

    "the structure of jet streams". which represents dynamical change rather than statistical change and here, at the moment, most of the models fail.  This is understandable 

    a) this is hard

    b) we don't yet know all the relevant input physics.

  • qusay f. Hassan asked a question in Review:
    Call for Editorial Advisory Board Members: Handbook of Research on Next-Generation High Performance Computing - IGI Global?

    Currently, I am in the process of editing Handbook of Research on Next-Generation High Performance Computing to be published by IGI Global (www.igi-global.com) scheduled for release in 2016. In order to strengthen the overall quality of this important publication, I am in the process of organizing an Editorial Advisory Board for this valuable reference and, based on your impressive research records, I would like to invite you to join this Board. As a member of the Board, you will be able to read papers about the current and future advances and challenges of high-performance computing and related technologies (e.g., Big Data, Internet of Things, grid/cloud computing, many-core, exascale systems, etc.) You will also receive a 40% discount should you wish to purchase a copy of Handbook of Research on Next-Generation High Performance Computing upon its publication.

     As a member of the Board, you would be asked to assist me with the process by reviewing proposals, conducting reviews of those manuscripts for which I need a reviewer, and assisting me with submission cases where conflicting reviews exist. Please keep in mind that we also will be arranging for a double-blind review process between authors to evaluate the submissions for this book.

     In addition to supporting the review process, you would also be asked to write testimonial statements in support of this book. I would also welcome any suggestions you might have regarding appropriate organizations or publications that may be interested in reviewing the completed publication.

     Authors are also welcome to send me their chapter proposals (2-3 pages) or full papers for inclusion in this book.

    If this invitation is agreeable to you and does not conflict with your current professional and research interests, please let me know by no later than January 7, 2015. Please let me know if you have any questions regarding this matter. You can message me here or send me a note on qusayfadhel@yahoo.com. I look forward to hearing from you soon!

  • Abbas Rahdar asked a question in Stoichiometry:
    In which deposition methods stoichiometry is maintained?

    In which deposition methods stoichiometry is maintained?

  • Sridhar Vadahanambi added an answer in Wear Testing:
    How to select optimum values for the Wear testing parameters such as Load, Sliding distance, sliding time, sliding speed?

    In order to prepare an experimental design of wear test, i need to find the optimum value or the range in which wear testing parameters to be chosen. The test material is a Aluminum metal matrix composite.

    Please provide the supporting journal or material. 

    Sridhar Vadahanambi · Global Core Research Center for Ships and Offshore Plants,

    There is an ASTM standard, ASTM G99-95 for pin-on disc wear test.. 

  • Jamshid Asadzadeh added an answer in Knockdown:
    The ways of manipulate gene expression in mouse?

    I am very interested about the possibilities to manipulate of genes in mouse, there is possible to knockdown a gene e.g. using cre-recombinase system but what can be used or which way should I start thinking if I want e.g. to knockdown one gene in liver, another gene in brain, third gene knockdown in kidney and at the different time points, the question is how many genes are possible to knockdown and not delete them completely but manipulate expression e.g. I want that in mouse at P12 days increased A gene in brain or especially in Hippocampus at 30% than expression of another gene B parallel to A would be increased at 60% and in adulthood would be decreased gene C so one (how many genes are possible to change maximal amount?).
    What are the limitations and disadvantages of current methods e.g. crossing knockout mice and crating double knockouts?

    Jamshid Asadzadeh · Columbia University

    Go CRISPR! 

  • Abbas Rahdar asked a question in Thin Films:
    PVD thin film uniformity is better than CVD or vice versa? why ?

    PVD thin film uniformity is better than CVD or vice versa? why ?

  • Artur Sergyeyev added an answer in Podcasting:
    Which sites and social media target young researchers?

    I just stumbled across an article which gives an overview of the the Viva Voce podcast http://www.vivavocepodcasts.com/ created to help young researchers promote their interests through displaying their profiles and publications. I have also read many interesting articles on DissertationReviews http://dissertationreviews.org/ - a site which publishes short reviews of archives, library collections, unpublished dissertations and related research young researchers are involved in. Are there any other similar initiatives (sites and social media) to encourage inexperienced researchers or where they can look for help from established scholars? The mentioned sites target PhD students in the fields of humanities and social science. I am also interested in sites that may include other fields, BA and MA students.

    Artur Sergyeyev · Silesian University in Opava

    In math there is the Young mathematicians' network. It is however not about promotion of young mathematicians but rather about career advice and related things:

  • John Mark Sim De Leon added an answer in Glaucoma:
    What is the main reason why transcleral diode laser cyclophotocoagulation is not a popular choice for primary or initial glaucoma treatment?

    Is losing vision the main reason? What are the reasons for losing vision?

    John Mark Sim De Leon · Cardinal Santos Medical Center

    Thank you Michel. That was an interesting video looking at the other side of the coin

  • What is the most appropriate method for overcoming seed dormancy whose tegument shows mechanical resitance to the embryo growth?

    I am studying the dormancy process in seeds that have mechanical resistance to embryo growth or the crossing by water or oxygen. Considering also that it is recalcitrant seeds, which methods can be used to overcome dormancy?

    Rafael Marani Barbosa · São Paulo State University

    I agree, the sulfuric acid is a good alternative. For seeds of Eugenia stipitata, in the few studies there for this species, the most effective treatment was the manual removal of the seed coat. Thus, the process becomes more viable with the use of sulfuric acid.

  • How can I deal with initial high O.D in enzyme activity assay?

    Last week, I did experiment for GST assay by using dilution-changed liver homogenate. (double concentraion of previous one.) as a result, I got more clear significant difference in activity. However, I encountered another problem. It's starting absorbance is too high (initial O. D is close to 1.0 in 340 nm, and over 2.3 after 5min). I'm afraid of this matter because it will be same for other assays, like SOD, CAT, GPx. For this reason, I seek to solve this problem, high initial absorbance. How can I deal with this problem? Oh, I think dilution is not the answer. I diluted, and I failed to get significant difference.

    Chung-Su Kim · Sungkyunkwan University

    Thanks, Hoseini. Actually, I worry about the color because current method of SOD assay's result is yellow(using pyrogallol), and homogenate's color is also yellow, but I can't dilute it because of lose of enzyme activity. So I should find the way to decolorate.

    Thank you for your recommend.

  • Kerrie D Pierce added an answer in Primer:
    In identifying ApoE polymorphisms using PCR amplification and simultaneous restriction digest, where am I going wrong?

    I've been attempting to replicated the ApoE gene using PCR, following the below protocol:

    2.5 uL of 10x Dream Taq buffer, 0.2 uL of Dream Taq Dna polymerase, 1uL of forward primer (F5′-TCCAAGGAGCTGCAGGCGGCGCA) , 1uL of reverse primer (R5′-GCCCCGGCCTGGTACACTGCCA), 0.5uL DNTP mix (10mM), water 16.8uL, and finally 1uL of my sample DNA

    Cyling

    94oC 2 mins

    94oC 30 seconds

    55oC 30 seconds

    72oC 90 seconds

    72oC ten mins

    * 40 cycle repeats 

    So far I have had no success and I cannot determine where my complication is and as this is my first time working with this gene I wondered if anyone could shed some light on the situation? Any advice would be greatly appreciated.

  • Julio Sanmiguel added an answer in RNA:
    Is there a simple method to find out if a protein binds RNA/DNA and if it binds, which RNA/DNA sequence is it?

    I suspect a protein I work with binds RNA or DNA, but I failed to find a simple and reliable method to prove that.   

    Julio Sanmiguel · University of Pennsylvania

    I believe you should be looking into nuclease protection assays. Good luck!

  • Alice Aziz added an answer in Execution:
    How significant is the death penalty deterrent effect when those on death row can enjoy their lives for at least 10 years before they are executed?

    After the abolition of the death penalty in some countries, did crime rate increase or decrease in those countries? Which better serves justice: the deterrent effect -if any- of the death penalty or the risk of executing a wrongfully convicted human being?

    Alice Aziz · Kolej Poly-Tech Mara

    Hai Jim. I am not backing up the criminals and not to the least saying that their suffering is equal to the horrible act they have done to the victim. What I am trying to say is that being detained in a prison while waiting for death execution should not be considered as “enjoyment” (referring to the question imposed by Aceil). Yes, despite of getting regular meals, TV, books, mail, visitors, education etc…I wouldn’t consider that as ‘enjoyment’. The waiting period is an opportunity for any new evidence, appeal or pardon. Honestly, not being sadist (0_0) …but I would prefer if the convicted for death penalty to be executed as soon as possible…(.-_-)

  • Rajesh Shukla added an answer in Elasticity:
    What is the difference between elastic stiffness and plastic stiffness? How they can be used for different material?

    My doubt is that whether we can use terms elastic stiffness and plastic stiffness or not. How stiffness is different from elastic stiffness and plastic stiffness

    Rajesh Shukla · Indian Institute of Technology Roorkee

    Respected sir, I know these relationships used for beam on elastic foundation. I am aware of  bending stiffness. I do not know these relationship for elastic-plastic beams.

    My doubt is that whether we can use terms elastic stiffness and plastic stiffness or not. How  term stiffness is different from  terms elastic stiffness and plastic stiffness.

  • Abbas Rahdar asked a question in Evaporation:
    In which of the deposition methods melting and evaporation step is there?and In which of the deposition methods only evaporation step is there?

    In which of the deposition methods melting and evaporation step is there?and In which of the deposition methods only evaporation step is there?

  • Emeka W. Dumbili asked a question in Monograph:
    Is ''PhD by publication'' better than 'traditional' PhD by monograph?

    In many universities, doctoral degrees are awarded based on one's published work. What are the benefits over the traditional doctoral process? Any disadvantage(s)?