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  • Abhijit Padhiary added an answer in Combustion:
    Can anyone help me with a partially premixed combustion in fluent for n-heptane?

    I am trying combustion of n-heptane in partially premixed combustion- with ignition delay model on - setting in fluent....

    but even on the inlet condition being fixed at high temp at 700K the combustion is not complete... its very small portion of combustion.

    Can you please suggest means to get correct auto-ignition time.. as it is coming in second !..

    Abhijit Padhiary · BITS Pilani, K K Birla Goa

    I think you can set the cell zone as fuel mixture provided you define the properties. I have no experience with CI combustion though. 

  • Miguel López-Lázaro asked a question in Drug Discovery:
    At what concentration should my drug kill or target cancer cells to have potential for therapy?

    The following articles answer this question. I believe they may help researchers involved in anticancer drug discovery assess in vitro and in vivo anticancer activity.

    A simple and reliable approach for assessing anticancer activity in vitro (Curr Med Chem. 2015;22(11):1324-34).

    Two preclinical tests to evaluate anticancer activity and to help validate drug candidates for clinical trials (Oncoscience. 2015 Feb 20;2(2):91-8)


  • Boris Shapiro added an answer in Polynomials:
    Any advice on degree 6 polynomials being a sum of at most three cubes?

    Is it true that any monic polynomial of degree 6 with complex coefficients can be represented as a sum of at most three summands each being the cube of at most quadratic polynomials? 


    Boris Shapiro · Stockholm University

     Dear Professor Breuer,

    I am a professional and know well what kind of questions one should put to a broad audience to stimulate people's interest. The question I posed is  elementary and unsolved and does not have a long history behind it. It might have an elementary answer (which I could not find). If somebody has any reasonable suggestion  about this case, I can easily generalize it to a small theory.

    As for the style of questions, my former advisor Professor Vladimir Arnold (the famous one) once said that there is a Russian style of formulating mathematical questions and a French style. The Russian style (which I try to follow) is to formulate a mathematical problem in its simpllest unknown case. The French style is to pose a problem in its maximal generality.

    Warmest regards, B.Shapiro

  • Jaspreet Kaur asked a question in Stock Solution:
    Soil Microbial DNA Extracion with Hurt et al (2001) protocol ?

    I am trying to extract microbial DNA with Hurt (2001) protocol and I have following queries regarding the procedure:

    1) While making the extraction buffer, something is causing precipitation, I guess it is SDS. I made all the stock solutions with the specified chemical concentrations and pH and also, I adjusted the pH of buffer to 7 and then I incubated in water bath. Some precipitation faded away after water bath incubation but, the color of buffer was still opaque. Is it usually like that or do I need to take some specific precaution to avoid this ?

    2) Before DNA extraction, I am grinding my soils samples after giving them liquid nitrogen treatment. Is it okay to do this step or I can grind samples right away in the first step with denaturing solution ?

    3) Is there any specific recommendation for RNAse concentration ? 

    4) What is the color of the DNA pellet usually ? Should it be pure white or it becomes white after bead cleanup procedure?

    I would appreciate if someone can address my queries,

    Thanks in advance,


  • Alma Patricia Salazar added an answer in Parasitic Diseases:
    Does anyone have experience in the implementation of content and language integrated learning at university?
    I'm interested in teaching Parasitic diseases to students of veterinary medicine using CLIL. I'm grateful for any help, first-hand experience, notice on the topic, guide to a web site etc.
    Alma Patricia Salazar · Universidad de Colima

    I teach at the tertiary level. I have implemented CLIL at the School of Tourism through a team approach. I am the subject matter teacher and 2 two language teachers support this initiative.

  • Nizar Matar added an answer in Surface Treatments:
    Does anyone know of a glue for substrate polyethylene?

    I am looking for a glue that can adhere on the polyethylene without surface treatment.

    Nizar Matar · An-Najah National University

    The easiest way to bond two broken PE pieces is to use a solvent like methylene chloride (Caution: DCM is harmful to health so this is done in fume hood). This solvent will soften & activate the region of bonding contact.  
    Usually, a small amount of the solvent is applied to both pieces and then they are joined before they dry. Alternatively, the pieces are joined and bit of the solvent is poured along the region to be bonded. The solvent will flow between the parts and link them but one has to wait until drying occurs.

  • Leonard Mehlmauer added an answer in Community Health:
    What is the most important priority in health promotion?

     Health promotion is very relevant today. There is a global acceptance that health and social wellbeing are determined by many factors outside the health system which include socioeconomic conditions, patterns of consumption associated with food and communication, demographic patterns, learning environments, family patterns, the cultural and social fabric of societies; sociopolitical and economic changes, including commercialization and trade and global environmental change. In such a situation, health issues can be effectively addressed by adopting a holistic approach by empowering individuals and communities to take action for their health, fostering leadership for public health, promoting intersectional action to build healthy public policies in all sectors and creating sustainable health systems.What is the most important priority in health promotion? What is your opinion about it?

    Leonard Mehlmauer · California State University, Long Beach

    Health promotion can involve both education and practice.  In either case, consider seven support disciplines:

    1-Diet, 2-Rest, 3-Exercise, 4-Natural Hygiene, 5-Right Occupation, 6-Life-positive Environments, and 7-Spiritual Cultivation.  

    DIET is important because the gross physical body is a food body.  The quality and quantity of the food we eat largely determines the health of the gross physical body and the lower sense mind and emotions.  REST allows the body to regenerate its energies.  EXERCISE, both rapid-movement and hatha yoga, helps allow the body to move thru space efficiently.  NATURAL HYGIENE provides balance and cleanliness.  RIGHT OCCUPATION is engaging the body-mind in productive and life-positive activities.  RIGHT ENVIRONMENTS are clean, wholesome, elegant and graceful, and involve entirely life-positive people (friends, relations).  SPIRITUAL CULTIVATION is study and practice of the sacred, the Permanent, the Eternal, the Great Consciousness That is the Context within Which everything appears.  Of these, the last is most important because it is about the greatest desire of every heart--Absolute Happiness.   

  • Mohammad Omer Faruck added an answer in HPLC Analysis:
    Have a nice day all of you. I want to do amino acid sequence analysis by HPLC. I want to know how to prepare a standard for HPLC?

    Have a nice day all of you. I want to do amino acid sequence analysis by HPLC. I want to know how to prepared standard for HPLC?

    Mohammad Omer Faruck · International Islamic University Malaysia

    thnks Ana Luisa de Montenegro..

  • Ozi Adi Saputra asked a question in GPC:
    Does anyone know about a simple method to determining of molecular weight especially in MW of polymer (Polyurethane)?

    I synthesized of renewable polyurethane, but I don't know the MW of my polymer. I know that GPC analysis was one of the method to determine the MW of polymer, but, Does anyone know the other method to determining of MW more simply, effective and economic? Regards

  • Vally Kommineni added an answer in Cell Biology:
    Cell Based Assays........
    Can some one tell me about Cel base assays ??

    How it is different from invitro assays????

    Plz tell me in the brief for understanding.......

    Vally Kommineni · Caliber Biotherapeutics

    Cell based assays qualitatively measure the function of the product/molecule. Assay plays a key role in determining the quality of biological products. Potency can be determined with  relevant cell-based assays, not just by one assay. Assay designing depends on molecule's MOA. In simple terms determining drug quality before risking in pre-clinical studies.

  • Timothy I. Hyde added an answer in PXRD:
    Unexpected sharp PXRD peaks for NP sample. Possible explanation? How can I get rid of these very sharp XRD peaks?

    I have a Fe/Cr nanoparticle system with average NP diameter of ~ 10 nm. I have verified NP formation via TEM analysis. However, during the powder X-ray analysis I have been observing extremely sharp peaks at lower 2-theta values (15-35 °). These peaks do not correspond to any metallic or metal oxide standards I’m utilizing. Can someone please explain why these peaks are appearing in my PXRD data? I suspected that organic ligand species might cause this, but that seems unlikely, as I have employed an additional ligand cleaning steps. Thank you for your valuable time.

    Timothy I. Hyde · Johnson Matthey


    Thanks useful product link,above.

  • David Neihguk added an answer in Publication:
    Can I share my Master's Thesis in public domain and publish contents from it later on?

    I intend to publish a chapter of my Master's Thesis in a upcoming conference which will happen next year in 2016... If I share my Master's Thesis in a platform like RG, will it jeopardize the prospect of my intended publication? I completed my Thesis recently in June 2015. 

    David Neihguk · Mahindra Research Valley

    Stephan... you made complete sense.. i completely agree with you. Thanks for the answer.

  • Francisco Brocal added an answer in Social Theory:
    Should I use a case study or phenomenological methodology for my study?

    My study is on the perceptions of worker's on their leaders' behavior relative to safety in their respective organizations

    I am thinking a case study but wondering if phenomenological methodology would be better.

    Francisco Brocal · University of Alicante

    I would like to show a new perspective on the issue raised. With any Occupational Safety and Health Management System (eg OHSAS 18000, ILO, etc.), the degree of integration of OSH in the General Management System of Company, should be measured. A key indicator for such measurement is related to the definition of roles of the different hierarchical levels (on OSH). In addition there must be evidence of the effective implementation of these functions. With these indicators, it is possible to indirectly measure the degree of perception searched.

  • Amer Bakhach asked a question in Time Series:
    Forecasting using exponential smoothing: accuracy and Tracking Signal?

    hi everybody,

    i am trying to develop my own adaptive exponential smoothing to forecast a particular time series.

    but i note the follow: the better the Tracking Signal is [-3.5;+3.5] (which is acceptable in my case); the higher Mean Absolute Error (MAE) i got!!!

    my questions:

    1-is this normal? or i may did something wrong?

    2- suppose that i have to focus on MAE; can i ignore the Tracking Signal?

    best regards;

  • Evert Ph.J. De Ruiter added an answer in Acoustics and Acoustic Engineering:
    Any suggestion for using new type of local wood-based materials for building sound absorption panels?

    any suggestion for using new type of local wood based materials for building sound absorption panels .

    Evert Ph.J. De Ruiter · Peutz consultancy , Zoetermeer (NL)

    Sound absorption is most universally realised by porous materials. Often they consist of mineral wool or plastic foam, but loosely bonded wood chips are a good alternative.

    Maybe fast growing (tropical?) types of wood are even better suited than pine wood. I am sorry to say that this is not really new...

  • Ramadan Elmgrab added an answer in Urdu:
    Is it necessary to have bilingual experts (with formal education) for translating a questionnaire?

    While testing a questionnaire for its validation and cross-cultural adaptation, is it necessary to have bilingual experts with formal education? E.g translation of Nordic questionnaire into Urdu (is it necessary that the translators have a formal level of education/degree in Urdu or English?)

    Could it be done by someone who is brilliant at both languages but does not have formal education? 

    Secondly, how is the sample size selected for translation-based studies like this? Inclusion and exclusion criteria and number of participants etc...

    Thanks in anticipation.

    Ramadan Elmgrab · University of Benghazi

    This depends on the type of your questionnaire, i.e. if the questions are easy and straight forward and free of linguistic and cultural mismatch, then you do not need experts.. But if  the translation is between two  incongruent languages and the questions are loaded with cultural specific items then you are obliged to seek help form an expert in the field of translation. 

    As to your second question, The questionnaire is based on the size of population you are dealing with. However, this is relative and  depends on your data.

  • Dorian Aur added an answer in Turing Machine:
    Can we fully simulate the whole brain on a digital computer?

    Miguel Nicolelis and Ronald Cicurel claim that the brain is relativistic and cannot be simulated by a Turing Machine which is contrary to well marketed ideas of simulating /mapping the whole brain  https://www.youtube.com/watch?v=7HYQsJUkyHQ  If it cannot be simulated on digital computers what is the solution to understand the brain language?

    Dorian Aur · Stanford University

    Dear Colin,

    "The labels for "meaningful information", "action potentials", and "synapses" can be rearranged for "task", "switch value", and "table to be updated" above to produce the correct order"

     The tendency in many brain projects is to  use  relational databases where massive volumes of heterogeneous data are included (e.g. characteristics of  genes, proteins, type of cells, local arborizations of various  neurons ). Having such data can be useful however it does not solve the fundamental issue.

    Replicating the brain function remains the fundamental problem  which cannot be solved on digital systems as long there is no real understanding of how the brain performs the process of computation.

    Under  action potential  "label" one needs to generate vibrations,  a broad electromagnetic spectrum that carry meaningful information.

    If the action potential is approximated  by 01 :

    "Action potential 01 (Na+), 10 (K+)
    Receptor potential 11 (Ca++), 00 (failed initiation)"

    you'll solely  build a brain  toy, like the iconic horse on a stick.

  • Amer A. Al-Atwi asked a question in Organizational Behavior:
    What are new concepts in organizational behavior?

    I need to know latest concepts in literature of organizational behavior. 

  • Ana Casali added an answer in Agent Based Modeling:
    Looking for papers on institutions and social influence, in particular any formal models, simulation work or agent based modelling?

    I am also interested in frameworks and theoretical works dealing with institutions and social influence.

    Ana Casali · Rosario National University

    The work about Electronic Institutions can help or inspire you, give a look to the IIIA in this direction


  • Alma Patricia Salazar added an answer in Self-Assessment:
    Are there informal ways/tools to encourage the self-reflection of teachers/lecturers on the way they give feedback to their students?

    In our curriculum the student needs to critically reflect on his own learning. But are the teachers capable of giving proper feedback in order to allow the student to grow in this competence? Are the teachers themselves capable of critical self-reflection? And if not, how can this be encouraged or triggered in a non-offensive way?

    Alma Patricia Salazar · Universidad de Colima

    As a teacher trainer, I ask teachers to reflect on their feelings and attitudes towards tasks, content, learning process they go through and usefulness of what is done. With my students, they also reflect and talk to each other about the same issues mentioned previously, and in teams they agree and write a proposal to improve, add, delete or change whatever they chose. I summarise  this information and promote online discussion so they can comment on their peers' insights.

  • Andréa Alves Araújo added an answer in Building Codes:
    Apart from Asbestos, are there other dangerous building materials still being condoned in building structures that harm humankind?

    Is Asbestos the only and most harmful building material against humankind?

    Andréa Alves Araújo · Federal University of Rio de Janeiro

    Danger almost invisible ...
    Often ignored, but present in the daily activities of sites, substances and chemicals can enter the body through the respiratory tract, skin and mucous membranes, causing damage to health.
    Present in paints, solvents, sealants, adhesives, cements and in a multitude of materials, chemical substances are substances, compounds or products which tiny particles are able to penetrate the human body in the form of dust, welding fumes, gases, vapors etc.
    The most common consequences of contact with these substances are skin diseases and respiratory. One of the most serious is silicosis, lung disease caused by inhalation of mineral dust in handling, breakage or cutting materials such as sand, mortar, tile, gravel, ceramic, concrete and bricks. Depending on the material to which the person is exposed as well as the type and contact time, other more serious problems can happen, poisoning of the central nervous system lesions in cancer.

  • Ellen S Vitetta added an answer in Cell Aging:
    What is the best strategy to get T cell Ag clones and expansion of these clones?

    If anyone has suggestion on getting T cell clones for Bacterial anitgens?

    Ellen S Vitetta · University of Texas Southwestern Medical Center

    I strongly suggest that you go back and read the scientific literature from the 1980-1990s where there are many papers on making Th and Tc clones! There were also entire symposia on this topic. 

    When in doubt, read !

  • Varoon Singh added an answer in Gas Chromatography :
    Hi can anyone advise me how to minimise peak tailing factor in GC methods ?

    At present Tf is 2.5 looking less than 2.0.

    Varoon Singh · Defence Research and Development Organisation

    Try changing solvent also, sometimes solvent do effect the cinematographic profile of the analytes.

  • Ahmed Gawhari added an answer in DNA Barcoding:
    What software do you recommend to compile sequencing data from 4 different plant DNA barcode regions?

    I am working on a project with orchids. We can generate phylogenetic trees using each barcode region independently, but we would like to generate a tree using the information from all four regions simultaneously. 

    Suggestions on which software we could use?

    Ahmed Gawhari · University of Reading

    Dear Alexandra,

    I suggest to use TaxonDNA (SpeciesIdentifierNEX.) If you need to concatenate your sequences in a single alignment., its an easy software.

  • Luisiana Cundin added an answer in Mathematics:
    When using the attached inequalities, how can the parameters be calculated?

    Dear Colleagues,

    Right now I am working with Prospect theory framework and I struggle with mathematical calculations part.

    I would appreciate any help, how using attached inequalities, the parameters are found out (the answers are given as well).

    Many thanks,

    Luisiana Cundin · Die Wand : leben heißt kampf

    I second Marek's suspicion of an error in the equations!! When I attempted to numerically solve them, something was awry. 

  • Amit Kumar added an answer in GHG emissions:
    Could anybody tell me the any regression equation for the calculate of greenhouse gas using soil organic carbon/labile organic carbon/C:N ratio?

    GHG emission from reservoirs/ forest soil if directly related to C:N ratio, LOC and SOC ..

    Amit Kumar · Indian Institute of Technology Roorkee

     Kenneth M Towe..thanks a lot for your kind reply ..but i want to say any regression equation for the calculate of greenhouse gas using soil organic carbon/labile organic carbon/C:N ratio?

  • Chetan Joshi asked a question in CST:
    How to characterize an inhomogenous dielectric slab in CST MWS?

    I want to characterize an inhomogeneous slab (variable permittivity & permeability) in CST for normal and angular incidence of 'plane wave'. The way I am doing it until now is by using a rectangular waveguide, as shown in the attached image. I find this method intutive, but the simulation can become heavy if the waveguide is placed at a distance from the substrate. 

    Are there better ways to do it in CST? All answers appreciated. 

    Sincere regards.

  • Asit Baran Samui added an answer in Corrosion Engineering:
    How can I calculate the corrosion rate?

    Kindly guide me how to calculate corrosion rate for nitrided steel in NaCl solution using polarization curves. 

    I have calculated Icorr, Ecorr using Tafel plots, and now i want to calculate Corrosion rate.

    Asit Baran Samui · Defence Institute of Advanced Technology

    I believe you got Icorr and Ecorr from electrochemical corrosion measurement by using Tafel plot. Chenge Ecorr by 10-20 mV and measure i and continue. Plot Eapp-Ecorr vs. i and from the slope get polarization resistance, Rp. two beta constants (anodic/cathodic) are already obtained from slope of anodic/cathodic plot. From these parameters you can calculate by using Butler-Volmer eqn. 

  • Dare Ojo Omonijo added an answer in Plagiarism:
    How to check for the plagiarism of a document freely?
    Today we have software tool, called "Anti-plagiarism software", that checks a document for plagiarism and reports the similarity score with proper citation and resources. We have many software tools like Viper, Grammarly and many other websites offering this service. I would like to know the popularly used freely & paid Anti-plagiarism software with good accuracy.
    Dare Ojo Omonijo · Covenant University Ota Ogun State, Nigeria

    Thank you for this information. You are blessed in Jesus name