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  • Ahmad Samir AlFaar added an answer in Papers:
    What would you consider if you have to review a paper for a workgroup you know they flood the journals with letters of insignificant research?

    A group of authors are flooding journals with short papers/letters with no significant importance discussing less than a dozen of patients in each paper or just commenting on others with no reason other than pushing others to cite their previous publications .. What would you consider in your review (if you are asked to review one of their papers) other the normal procedures? .. would you tell the editor?

    Ahmad Samir AlFaar

    yes, that is true, I agree with you in this point.. but.. What if ? 

  • Mohammed ayad al mashat asked a question in Genetic Algorithm:
    Kindly, what are the relevant references about the genetic algorithm that you used ?


    what are the relevant references about the genetic algorithm that you used ?

  • R. Chemali asked a question in Finite Elements:
    Hello, I have a question, I want to model a building (structure) with finite Elements and I introduce the nonlinear compotement ?

    I have a question, I want to model a building (structure) with finite Elements and I introduce the nonlinear compotement (eg Bouc-Wen model) under seismic excitation.
    Is there a book or the document explaining the procedure of this modeling.
    Thank you

  • Aayam Gupta added an answer in End of Life:
    Anyone working in the field of AYUSH intervention in palliative care, or end of life care?

    I am searching for research literature and scholars working on Indic perspectives on end of life care. Can anyone who has been working or published in this area may kindly share their experience and published work? Thank you.

    Aayam Gupta

    Kind Attn: Lavekar sir, I am using End of Life Care (EOLC) and Palliative care in this context -  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4154162/

    Also searched elsewhere...http://healthycanadians.gc.ca/health-system-systeme-sante/services/palliative-pallatifs/index-eng.php

    Kindly advice if someone is working on Alternative medicine as an intervention in EOLC?

  • Yasser Awad asked a question in Substance Abuse:
    Could you please supply me with hot topics about proposal of substance abuse?

    all researchers

  • Abdelaziz Gaouar added an answer in Soil Erosion:
    Does soil texture have effect on soil erosion?

    I need several papers about "effects of soil texture on soil erosion.

    I want to compare two different soil texture: 1) clay-loam and 2) sandy loam

    Abdelaziz Gaouar

    la réponse est claire, les deux textures sont sensibles à l'érosion pour une pente de 2  à10% et un couvert végétal de 30 à 40%, selon le diagramme que j'ai développé! L'érosion est de 50 à 60%. Clay-Loam est plus résistant, mais Sandy-Loam est moins résistant. Je peux vous en voyer le diagramme si vous voulez

  • Sebastian Schmitt added an answer in Protein Isolation:
    Where can someone find E. coli BL21 strain ?


    As the title describes, we are looking for the BL21 E.coli strain to use it for a demonstration and experimentation with bacteria and protein isolation in some high school classes in Biology lesson.

    Does anyone know a way to get access at those cells ? Is there any institute or university or even a person that can send in Europe and more specific in Greece some cells in a micro-tube ? 

    Thank you very much.

  • Umar Aminu Mohammed asked a question in Distillation:
    10g of a substance dissolve in 1000ml of distil water, how do you get 50%, 20% and 40%?

    plant physiologist, chemist

  • Soheila Ghambari added an answer in Meta-Heuristic Algorithms:
    Can anyone help me?How can I encode solutions in reliability optimization problems?


    I'm new in reliability optimization problems topic. I want to solve these problems with meta-heuristic algorithms. How can I encode solutions for generating initial population?

    Soheila Ghambari

    Thanks all for answers...

    In fact my chromosome includes some subsystems. Each subsystem has (n) components and a reliability  ( r).  It is better to say each subsystem has two parts: real and integer numbers.  Chromosome represents a solution of mixed-integer problem. that

       0 < r <    and   n ϵ Z

  • Stephen Joy added an answer in Scientific Research:
    Do You Think “Publish or Perish” is a “Stick” Approach to Motivate Researchers to Conduct Research?

    In order to motivate a person to do something, generally we can use “carrot or stick” approach (see picture below).

    In academic research, generally do you agreed “publish or perish” is a “stick” approach?

    What do you think will be good examples of “carrot” approach to motivate researchers to conduct research?

    Stephen Joy

    "Do this or die." Yes, that's a threatened punishment ("stick"), all right.

    Positive motivators? They fall into two groups. Most simply provide valued rewards for doing something. Examples would include better offices, more lab space, money to go to conferences, and so forth. So the more productive department members would enjoy a better quality of life as a result of their labors. This will keep them working, but won't actually make them love the work any more.

    The trickiest task is to create genuine motivation - to get people to actually want to do the task for intrinsic reasons. Social rewards help here, but I think our levels of intrinsic motivation are often determined during our training experiences. The basic idea is to make the work fun in and of itself. The goal is to have people feel as Curt Richter did when he said, "I enjoy research more than eating." You might want to have a look at the achievement motivation literature from the 1950 - 1980 period, especially the work of David McClelland and John Atkinson.

  • Matteo Paganoni asked a question in Fluid:
    How can we distinguish between real morphology and artefact within a fluid-escape pipe in 3d seismic (sometimes called chimneys)?

    ...''Fluid escape pipes as defined here as highly localized vertical to sub-vertical pathways of focused fluid venting from some underlying source region and are recognizable on seismic data as columnar zones of disrupted reflection continuity, commonly associated with amplitude and velocity anomalies, and scattering, attenuation and transmission artifacts (from Cartwright and Santamarina, 2015)...''

  • Larissa Kraus asked a question in Glycine:
    What is the glycine concentration of FBS?

    Does anybody have an idea what the (average) glycine concentration of FBS is? Or literature about it? I know that the composition of FBS is highly unknown and can be very different throughout different charges. 

    Anything that might help is very welcome, thanks!

  • Martha O'kennon added an answer in English Language:
    Do you think that English is a good language for Science?
    I write literary books and scientific articles and for expression of more details I prefer my native language because I think it is more complex and has a wider vocabulary. On the other hand, English expresses well many things with less words. When I translate scientific papers to English, I prefer the latter because it makes things clear with less words. (And with this amount of words normally it is more clear than with more words in my language). I think it is a good language for science.
    Martha O'kennon

    I wonder what the great Irish patriots would think today to see how many people are studying Irish now.  It's a terrific development! 

  • Bachir Achour added an answer in Happiness:
    Is happiness determined by genes?

    Dear All,

    Is happiness a nature or nurture classification?

    Thank you and best regards.

    Mariam Ahmad

    Bachir Achour

    Dear Mariam,

    There are several weeks ago, I read an interesting article which says roughly what follows :

    Why in some countries they are people so happy? In Denmark, it would seem that happiness is printed in the DNA of people. "Happiness flees those who seek it." That is a saying that makes no sense in Denmark because, precisely, the Danes have no reason to run after happiness: he would be part of their DNA. Yes, this is the science that says this fact. It is that Denmark is regularly at the highest levels of the national rankings on happiness, including one developed in 2014 by the United Nations. The evidence is provided by the graphics that I join you. "Generosity", "freedom to make choices," GDP "welfare" are major strengths of Denmark, a country already rich, progressive and with good social protections. In short, a country that has almost everything. That what underlines a study done by two economics researchers, Eugenio Proto and Andrew Oswald. Regardless of the quality of life of the country, their finding reveals that there is another factor conducive to happiness: the genes. According to the study, Danes therefore have a favorable genetic panel to rejoice.

    Initially, the two economists examine international study data from 131 countries, through variables such as GDP, geography, religion, etc., they discover that the more a country is far from Denmark, the less it is happy. They then seek to determine if this relationship is seen across generations and migration by examining, among others, the data reported on the welfare of the American people. Result: happiness of Americans is linked to that estimated in the country from which their ancestors came. This is how they came to be interested in the genes. A research topic that is not new since science has already shown that there is a link between genetics and the feeling of being happy. A history of serotonin and neurotransmitters that would influence our well-being ... A variant of this gene is linked to depression. But the two economists found that the population of Denmark (but also the Netherlands) has a very small percentage of people having this rather unseemly gene.

    It has identified that people who have more serotonin - a neurotransmitter involved in particular in the ability to respond positively - more easily confront difficult situations and are less likely to become depressed than others. Serotonin is therefore a protection against depression.

    With my best regards

    Prof. Bachir ACHOUR

  • Maia Chankseliani added an answer in Journal Impact Factor:
    How can i evaluate the journal to submit my manuscript?

    As a new researcher, I'm unable to evaluate the journals. I recognized that there are two metrics to evaluate the journals:  impact factor and the index but really I don't understand what these metrics refer to? and should I choose the highest impact or the smallest? and what is the influence of index? Also, I recognized that journals still using 2014 impact factor on their sites, why?

    Please could you elaborate these metrics?

    Maia Chankseliani

    Some of the questions I would ask are as follows. Where do some of those academics that you intellectually engage with publish their work? What are some of the main professional associations in your field and do they publish a journal? If you have your draft manuscript prepared already, have a look at the journals where some of the articles from your references have been published in.

  • Huda Al-Battashi added an answer in Fermentation Biotechnology:
    What is the best techniquie used to filter culture media from 100L bioreactor to be used again in the same fermenter with an other different bacteria?

    Actually I need to use the filtrate of the first fermentation in the next fermentation step. I need to sterile the filtrate and use it again.

    Huda Al-Battashi

    Thank you alot dear

    Ok I will try that ^_^

    My regards

  • François Xavier Nshimiyimana added an answer in Soil Contamination:
    How calculate health risk, from soil contamination (by heavy metals or pesticides) according to US EPA Method, ?

    Can you help me, please. I want to make the assessment risks in soil. with the documents support, if you have. thank you

    François Xavier Nshimiyimana

    Thank  you  very much C. Mei-Ling Hamilton, 

  • Leonidas A. Papakonstantinidis added an answer in Business Analysis:
    How calculate idiosyncratic preference shock?

    Hi, households form demand functions for each differentiated good based on their sentiments and the idiosyncratic preference shocks on each good.Unlike households, firms do not directly observe households’ sentiments or idiosyncratic preference shocks. Firms instead receive a noisy signal about their demand, which is a mixture of firm-specific demand (idiosyncratic preference shocks) and aggregate demand (sentiments). I want to Implement this idea empirically. How calculate idiosyncratic preference shock? what data or database use for calculate it? Please, an empirical exploration show or introduce me that use or extract this variable. 

    Leonidas A. Papakonstantinidis

    I 've completed the chapt V of my work on "win-win-win papakonstantinidis model" based anong the others on "personality concept and the "screening and  signaling  in the contract theory

    more details, in 

    Screening in economics refers to a strategy of combating adverse selection one of the potential decision-making complications in cases of asymmetric information   concept of screening was first developed by Michael Spence (1973) and should be distinguished from signaling which implies that the informed agent moves first.

    In contract theory, signaling is the idea that one party (termed the agent) credibly conveys some information about itself to another party (the principal). For example, in Michael Spence’s job-market signaling model[2], (potential) employees send a signal about their ability level to the employer by acquiring education credentials. The informational value of the credential comes from the fact that the employer believes the credential is positively correlated with having greater ability and difficult for low ability employees to obtain. Thus the credential enables the employer to reliably distinguish low ability workers from high ability workers

  • Saifeldin Mohamed Khair Abdelrahim added an answer in Economic Efficiency:
    Gray water treatment with advanced technologies, your kind hints ?

    what is the easiest and economic efficient method of treatment of waste water 

    Saifeldin Mohamed Khair Abdelrahim

     thank you dears

    Anas and Baboo, these are quite beneficial info, and will really light  up my way

    I  appreciate your help-full   guides 

  • Andrew Worsley added an answer in Mass:
    If a non zero rest mass object is moved at speed of light how much its mass should be appeared?

    I know most of the answers will say infinity, but still this needs deeper look about its physical meaning and does it consider a practical logic?

    Infinity usually used for something we could not measure, however the reality may be different!

    Andrew Worsley

    Universe is accelerating in its expansion- far from static

  • Haroon Rashid added an answer in Root Canal Therapy:
    Root canal therapy Versus Dental Implant: Are we misleading our patients?

    Not a fair amount of information is given to patients while choosing between implant versus endodontic therapy. There seems some sort of disagreement between endodontists and implantologists. Not all but few are always promoting implant as solely beneficial treatment, often underscoring benefits of endodontic treatment and highlighting disadvantages of endodontic treatment. 

    Haroon Rashid

    Dear Ashok,

    You've asked a classic question and this debate has been going on for years. Well, to answer now ... I think you can find 100s of papers favoring implant placement and on the other hand, many papers can be found which state that root canal therapy should be the treatment of choice.

    Now I strongly believe that the choice will depend upon the scenario you are facing. There may be instances where implant placement is contraindicated because of medical or dental reasons and you may not have a choice. On the other hand, there may be instances where implant placement could be the choice. This will actually depend upon the prognosis of the tooth. This question is difficult to answer and treatment planning would again be the key here. You must do careful case selection in case you decide any of the treatment modality.

    During my 15 years of clinical experience, I tend to convince the patient for an endo or a re-endo because I would want to preserve the natural dentition and the PDL (but then I do consider the prognosis too). If there is no hope then I would plan for implant placement.

    I wish you all the best for your decisions.


  • Stephen Joy added an answer in Psychotherapy:
    Is there a framework to evaluate psychotherapy research methodology?

    I am planning a study about psychotherapy research in my country. My aim is to describe the themes that have been researched, but also to evaluate the methods, designs, techniques and analysis that researchers have used. It would be helpful if there is an established framework to use in this evaluation.

    Otherwise, my plan is to compile a framework based on literature about methods of psychotherapy research. It would also be helpful if you can recommend such literature.

    Stephen Joy

    The "state of the art" framework would probably be the CONSORT 2010 standards. These cover all sorts of clinical trials. For psychotherapy, add the "Extension" for non-pharmacologic clinical trials. You might also want to include the extension for cluster randomized trials.

    Most actual outcome studies won't be able to meet every CONSORT standard, but the ways in which our individual studies fall short should be discussed when reporting our results.

    Here is the link to the CONSORT home page. All the checklists and at least some of the related position papers should be available here.

  • Simon Chang added an answer in Blood Collection:
    How to store blood prior to DNA extraction??

    I am collecting blood samples, but the samples will be stored in freezer for couple of years before it is sent out for gene analysis. Could you please advise what would be the best way to store the sample for long term?

    1. How much blood should be collected? 

    - I am using finger prick, so maximum whole blood I can get is 100ul-150ul. Would this be sufficient for gene analysis?

    2.  Do I need to use EDTA tubes for blood collection?

    3. Prior to storage

    - shall I centrifuge and only store the cell pallettes? or whole blood in EDTA tubes? 

    - or shall I use purifying kit such as QIAamp DNA Micro Kit (which I want to avoid if possible)

    4. Do you recommend western blot? what is the limitation with this method?

    5. What portion of the blood is used for gene analysis?

    - serum? plasma? cell pallette? 

    I would appreciate your advice!! thanks!! 

    Simon Chang

    150 ul whole blood and it depends on what analysis you are going to do. The volume is decided by DNA or RNA concentration

  • Shankar Subramanian added an answer in Dermatomyositis:
    Calcinosis in juvenile dermatomyositis?

    Female patient, 13 years old diagnosed as juvenile dermatomyositis...

    she is on alendronate, colchicine, aluminium hydroxide for calcinosis and mycophenolate mofetil, Prednisolone for the disease activity.

    Unfortunately, new nodules of calcinosis still appear and her calcium level either total or ionized decreased. 

    How should I manage that case?

    Shankar Subramanian

    Dear Arwa Amer,

    Firstly most reports for treatment of calcinosis have spanned over 12 months or more for any kind of resolution. No consensus has been achieved about the effective treatment for calcinosis in DM, and the data available in the literature are based only on reports and/or case series.

    Besides the drugs you mentioned, the ones that have been successfully used include the following

    Diltiazem , Probenecid, Intralesional steroids, Etidronate, Thaidomide, Low dose warfarin and Infliximab.

    Check out this article attached. The references can be gone though systematically to review the role of each individual drug


  • Victoria Muzalevskaya added an answer in Middle East:
    Can you give me any advice, comment or link on resources for Bush's Senior Middle Eastern and Syrian policy?

    Hi! I'm writing a Master research paper and need any advice, opinion or comment on Bush's Senior Middle East and Syrian policy. In particular, I'm interested in groups of interests, parties' opinions and programs of this time in the framework of American and Syrian relations and US policy towards Syria. Literature, web sources and personal opinions and comments would be greatly appreciated. Thank you :)

    Victoria Muzalevskaya

    thank you a lot Bowden! :)

  • Perikles Simon added an answer in Physical Exercise:
    What should be the ideal method for measuring intensity and total calorie of physical activity?

    There is an endless list of studies on effect on physical exercise on metabolic disorders like NAFLD. Most have used self reported questionnaires especially in retrospective studies which have an inherent recall bias. What should be used for a prospective study in this field? Pedometers or accelerometers or any other instrument? 

    Perikles Simon

    Dear Preetam Nath,

    the NAFLD is also a interesting group we are currently studying.

    The best option to assess changes in metabolic function and fitness would be an intervention study that measures physical fitness (VO2max) and VT1 (ventilatory threshold) by spiroergometry at study entry and end. Indirect spiroergometry will also enable you to assess increases in fat utilisation at a given exercise intensity.

    However, studying adherence to your exercise intervention is the major obstacle to solve. Compliance does not seem to be too high, if you go for measuring tools like pedometers, heart rate monitors or accelerometry. Accordingly self-reported questionnairs are still inevitable. Might be worth while to assess the IPAQ every 7 days:


    If you come accross a better solution, please let me know.


  • Mary Beth Martin added an answer in Mind Mapping:
    Does anyone know good sources for mind mapping and reading comprehension?

    I am interested in helping first-year college students and ESL students become better academic readers. 

    Mary Beth Martin


    Thank you. It's amazing to find someone to help from Panjab University. Thank you again. I will check the sources you suggest.

  • Mustafa Tekke added an answer in Positive Psychology:
    Do you suggest any books for psychology, abnormalities, and positive psychology?

    Do you suggest any books for psychotherapy, abnormalities, and positive psychology?

    Mustafa Tekke

    I believe they are useful, thanks indeed.

  • José Elias Feres de Almeida added an answer in SPSS:
    How to calculate (β0, β1, β2 ) in Modified Jones Model ?

    Equation Jones model

    TACit/Ai,t-1 = β0 (1/Ai,t-1) + β1 (ΔREVit/Ai,t-1) + β2 (PPEit/Ai,t-1)+ ԑit

    How to run this equation in spss and what the correct coefficients for (β0, β1, β2 ) that will use in the second equation to get non-discretionary accruals?

    José Elias Feres de Almeida

    It looks complicated, but it's not. The discretionary accruals are the regression residuals. Just run the model Total accruals/TAt-1 = b0 + b1 1/TAit-1 + b2 ΔREV/TAit-1 + b3 PPE/TAit-1 + eit, where TA is total assets of firm i in period t-1. Also you can use the Modified Jones model adjusting changes in revenues minus changes in receivables. Or you also can run the model without the constant. It's your choice just justify your model in your paper according to previous study or use the most used version of the model. Then, your eit (residuals) variable is the discretionary accruals. Just predict it or ask your statistical software to create this variable (DACC). Good luck!

  • Azzam K Almosallami added an answer in General Relativity:
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Azzam K Almosallami

     Dear Matts Roos,

    the non locality of the gravitational field energy is a serious problem for General Relativity!!!!!!!!!! But none want to understand that...why???? 

    18Here is wisdom. Let him who has understanding calculate the number of the beast, for the number is that of a man; and his number is six hundred and sixty-six.