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  • Mahmoud Bajideh added an answer in DNA Sequencing:
    Does anyone has the protocol of purification for presequencing steps?

    I use sodium asetat 200 micro liter and EDTA 2 micro Liter and absolute Ethanol 50 micro liter in the first step, and then centrifuge 13000rpm in 15min,and decant supernatant and adding again 100 micro liter absolute Ethanol. but I do not know it is useful.
    I performed sequene for my PCR_PRODUCT and saw noises in PCR_PRODUCT. how i can decreese these. i think the noises creat of my purification. Is not it? thanks a lot for your attention.

    Mahmoud Bajideh · Buali Sina University

    thanks a lot, My volume of sample is 20 ul.

  • Asish O Mathew added an answer in Organizational Theory:
    Challenge question about one of the hottest issues in research methodology?

    Please guys I need your help

    In an organizational research, Assume there are two independent variables named X and Y; and the research aims to study the effect of X and Y on the dependent Variable named Z.

    Till now, doing such study has no problem; but the question is:

    Can I combine X and Y (items) and study the effect of both of them together at the same time on Z.

    IF yes, which theory can cover such this methodology?

    IF no, please Justify why

    Thank you

    Asish O Mathew · Manipal University

    Dear Mohammed,

    Multiple regression gives you individual effects of X & Y and also the combined effect of XY  that is the interaction effect (if that is what you are looking for).

    But if you want to combine two factors and make it one factor (provided it is theoretically acceptable) there are two ways:

    1. Structural Equation Modeling as Islam has mentioned in the previous post.

    2. Perform an principal component factor analysis for all 40 questions (both X & Y combined) and specify the number of factors to be extracted as 1 (This option is there in SPSS). This will reduce the two factors (X & Y) into one single factor (say A), but with reduced questions. Then you can perform a simple linear regression between the factors A and Z.



  • Alain Manuel Chaple Gil added an answer in Open Access:
    How do I upload the final version of my article?

    One of the co-author's uploaded the 'In Press' version of the article. How do I remove this and upload the final version (which is open access)?

    Alain Manuel Chaple Gil · Universidad de Ciencias Médicas de La Habana

    The coauthor most deleted you can`t do it...

    Good luck and best regards.

  • Mohammed Al-Amri asked a question in Art Education:
    Are there any researches using colours as assessment tools in art teacher education/art education?

    I'm looking for any references/ researches/ books using colours as assessment tools or techniques in assessing/evaluating students performances/ learning outcomes in any education siting in any disciplines specially at higher art education. Any recommendations,, please.

  • Richa Dhir added an answer in Plant Extracts:
    I have an unknown plant extract soluble in water, which solvent should i use for column chromatography?

    The extract was partially soluble in methanol. In soluble in hexane, ethyl acetate and chloroform. 

    Richa Dhir

    Dear Sir Bhuiyan. My extract dissolves in water to my understanding it should be polar in nature and not non-polar. The problem i am facing is that it is sparingly soluble in other polar solvents like methanol. Whereas it does not dissolve hexane and chloroform. 

  • Rahul Jain added an answer in Abaqus:
    How to model Eulerian regions in a Coupled Eulerian-Lagrangian simulation in ABAQUS ?

    Hi everybody,

    I need to run a blast simulation in ABAQUS using CEL technique.

    The model need a soil section, a mine (TNT) section, air and the vehicle under study.

    I've imported a vehicle CAD model into the workspace, assigned the solid section to the vehicle and have generated the Eulerian part.
    So using "Predefined Fields" how should I assign the remaining Eulerian space (excluding the vehicle) as air, or as a general question, how could I subtract any object from an Eulerian part so I could assign materials accordingly ?

    Rahul Jain · IIT Kharagpur

    This error normally designates to the inconsistency in the unit system

    kindly check properly you have used a consistent unit system. specially for unit of density

  • Gideon Holan added an answer in Pedodontics (Pediatric Dentistry):
    What is your opinion about reimplantation of avulsed decidous anterior teeth?
    I understand that most authors do not indicate the reimplantation of deciduous teeth, but maybe they generalize the treatment with an NO answer for reimplantation. I think they could enhance the subject and I give the question of the possibility of reimplantation in cases where the condition of the tooth and the child are good, the child is under 4 years old, good behavior, the time that elapsed between the accident and the visit to the dentist is less than 30 minutes, the tooth was well conditioned, do not you think it worth a try? And about the procedure of cutting the apex of the root to minimize the possibility of trauma to the tooth germs of permanent teeth, what you think about this procedure?
    Gideon Holan · Hebrew University of Jerusalem

    Your idea, Dr. Cardenas is interesting. The problem in collecting information from a large group of dentists is that each one provides a different treatment. Knowing this limitation we can still try to collect information and create a data base. The first step should be to compose a questionnaire that will include all necessary information about the injury, the treatment rendered and the consequences. The second step should be looking for the best way to distribute the questionnaire to as many dentists as possible providing a response system and  a site in which the data will be kept. We should make a pilot analysis on a relatively small group of cases to make sure that our questionnaire is relevant.  The last point is the statistical analysis of the data when we believe we have enough cases. I did not mention yet the need to finance such a study.

    I call you, Dr. Dario Cardenas, Dr. Carolina Mohamed and Dr. Yango pohl to create a research group to investigate the outcome of reimplantation of primary teeth.

  • Pavan Kumar A. V. asked a question in Grid Integration:
    Designing a three-phase grid synchronizing inverter without PLL?

    Can i design grid synchronizing inverter without  PLL..can you suggest me any other or alternative methods of designing grid synchronizing inverter. The main area of focus is in Renewable energy grid integration.

  • Fahim Wazir asked a question in Migration:
    Other than employment and tourism migration, what are other reason why people migrate from one country to another?

    For example, does education can be reason people to migrate to another country?

  • Aniruddha Maity added an answer in Seed Germination:
    How do nanoparticles influence seed germination?

    I have observed, at a certain dose nanoparticles promote seed germination. Some antioxidant enzymes get influenced, also pathogen attack on seed gets impacted. But what could be the exact mechanism behind the enhanced germination and/or vigour of seeds? Please suggest some clues.

    Aniruddha Maity · Indian Grassland and Fodder Research Institute

    That's right Dr. Arpana. Seed can easily take up nanoparticles. But how does it influence the germination process?

  • Debarati Nag asked a question in Terrain:
    What can be the probable explanation for the cumulative frequency curve?

    The frequency curve is of a clay bed from a valley lake deposit in a mountanous terrain.

    extreme care is taken when sampling so mixing of samples may not be the case.

  • Arno Gorgels added an answer in Event Horizon:
    What do you think about the S. Hawking`s idea of the solution of information paradox?

    "I propose that the information is stored not in the interior of the black hole as one might expect but on its boundary, the event horizon,"

    At Monday's public lecture, he explained this jumbled return of information was like burning an encyclopedia: You wouldn't technically lose any information if you kept all of the ashes in one place, but you'd have a hard time looking up the capital of Minnesota.

    The translations that occur form a sort of hologram of the original particles, Hawking said -- a hologram in the sense that 3-D information is recorded on a 2-D surface. When radiation leaves the black hole, it carries some of that information preserved on the event horizon with it.

    Arno Gorgels · Principia Naturae

    Well, talking about informative content: in fact, it is a rebirth!! 

  • Sharanbhoopal Reddy asked a question in Soil:
    What is the maximum time period (after sampling) for soils to carryout enzyme activity and soil microbial biomass determination?

    When soil samples were sampled for determination of biological activity (mainly for enzymes activity and microbial biomass carbon), is there any time period considered for further analysis or else analyzed just after sampling? If Yes, what is the maximum permissible time so that there would be no change in biological activity of a given soil?

  • K.M.Sajid Ali added an answer in Phylogenetic Tree:
    What software Should I use for Phylogenetic tree construction for Bacteria?

    Can anyone suggest some standard free software used for Phylogenetic Tree construction for Bacteria.. (in specific Actinomycetes/Streptomyces species).,

    I am looking for user friendly or less complicated softwares.

    Thanks in Advance


    K.M.Sajid Ali · Maharashtra Hybrid Seeds Company Limited

    no more suggestion beyond MEGA

  • Tapan Chatterji added an answer in Superconductors:
    Are there any superconductors based on double-exchange?

    Based on the similarities between the cuprate superconductors and the Mott insulator, La1-xSrxMnO3, wouldn't it be fair to define the superconductivity of the cuprates in the following manner?

    Cuprate superconductors are Mott insulators whose electron-electron interactions have been switched from antiferromagnetic to ferromagnetic.  This is accomplished by removing some of the 3d9 electrons, resulting in Cu3+ ions with a 3d8 electronic configuration.  Electrical conduction occurs because of electrons "hopping" between the Cu2+ and Cu3+ ions.  This interaction is mediated by the oxygen atoms that are shared by the Cu2+ and Cu3+ ions. 

    Tapan Chatterji · Institut Laue-Langevin

    The ground state of pairs of hopping electrons is a ferromagnetic metal as Zener had shown. Nobody showed that they could be superconducting but nothing is known for sure in the field of superconductivity. To say something more you have to do quantitative calculations. Just speculations do not help.

  • Mir Dost added an answer in Innovation:
    What are the main differences and/or similarities between Innovation Generation and Radical Innovation??

    Any strong arguments to justify either innovation generation and radical innovation are similar or both are different in terms of:

    - their nature (degree, antecedents etc)

    - performance

    - ???

    I will appreciate your response. thanks in advance.  

    Mir Dost · Asian Institute of Technology

    Thank you very much prof. Aaron Shenhar for your utterly useful response. May i request if there is any specific research article besides your book which distinguishes innovation generation and radical innovation? Thanks again

  • Subhash C. Kundu added an answer in Criminals:
    Should child criminal and an adult criminal actually be treated differently?

    I am referring to the article in the link. In case of age as a criteria for punishment, should other determinants of psychological growth such as IQ, EQ and  mental age etc also be considered before deciding the future course of law? Further how is it that a person less than 18 is juvenile and above 18 is an adult?

    How reasonable is it to only consider age and not other variables like sex, social status etc?

    Subhash C. Kundu · Guru Jambheshwar University of Science & Technology

    Usually minors are treated differently under the law.

    Juvenile law is law pertaining to those who are deemed to be below the age of majority. The age varies by country and culture.

    However, even when someone is considered to be a minor they may be prosecuted as an adult. Young aged between 13 and 18 are assumed irresponsible, but they can be involved in a criminal sentence if circumstances and juvenile delinquent personality justify it.

    The Federal Juvenile Justice and Delinquency Act of 1974 settled up four key requirements for American minors:

    --First, the deinstitutionalization of status offenders, i.e. moving them from juvenile hall to community based or family based environments.
    --Then, segregation (sight and sound separation) between juvenile and adult offenders
    --A strong limitation for the juvenile justice system to put juveniles in adult jails.
    --At least, protection of minority groups from being overrepresented in high-security facilities.

  • Alberto Castro-Ortega asked a question in News:
    What are the open problems related to Beltrami Equation?

    I'm studying the Beltrami's equation and I'm interested in new research, Where can I find recent open problems?

  • Lukman Raimi added an answer in Questionnaire:
    Survey design: do you show construct names to your survey respondents?

    We have a questionnaire including several constructs and each construct contains four questions. I have a discussion with a colleague of mine who believes that construct names should be visible on the questionnaire (as titles on top of the respective questions), while I think such visibility might increase response bias.

    For instance, if a construct name is 'organizational culture', and one believes that organizational culture around the understudy topic is great, s/he may answer 5/5 to all the questions of that construct without paying much attention to the questions.

    My colleague believes it is standard and common to show construct names. What do you think? I appreciate if you could share any references that you know of to support your thoughts.



    Lukman Raimi · Yaba College of Technology

    not necessary a general survey, but for some specialised survey you may need to include

  • Vega Pamela asked a question in Alcohol:
    How to dissolve PVA (Poly vinyl Alcohol) in water corectly ?

    How to dissolve PVA (Poly vinyl Alcohol) in water corectly ? i have been dissolving for 4 hours at 90 celcius with stirrer. but has not been dissolved

  • Watheq J. Al-Mudhafar asked a question in EOR:
    Is it possible to create transverse fracture for EOR process in unconventional oil reservoirs?

    Is it practically possible to drill one or multiple vertical wells to create transverse fracture for CO2 injection at the top of shale oil reservoir in EOR processes?

  • Khamael Abbas asked a question in White Blood Cells:
    Hello,How can I extract features using Higher Order Spectral ?

    I want to classify White blood cell image,so I need to extract  features using

    Higher Order Spectral. Can anyone have a paper that explains HOS algorithm or procedure? 

  • Krishnayan Haldar added an answer in Surface Tension:
    What is the relation between drop volume and surface tension of two different liquids?

    Water and surfactant solution both have different surface tension. Also a single drop of these liquids dispensed from needle will have definite volume. Is there any proportionate relationship between drop volume and surface tension?

    Krishnayan Haldar · IIT Kharagpur

    Can anyone provide me the pdf version of the paper?

  • Watheq J. Al-Mudhafar asked a question in Fractured Reservoirs:
    What is the benefit of micro seismic data in hydraulic fractured simulation?

    Some times, they include micro seismic data in hyspdraulic fractured reservoir simulation. What is the specific influential purpose for that? Does it have some effect to determine the location of HF?

  • Josef Chmelar added an answer in Silica Nanoparticles:
    I characterized Silica nanoparticle (commercial Ludox) using TEM and SAXS. Both techniques give me different sizes; what can be the reason(s) ?

    TEM images show a size of 14 nm whereas SAXS analysis reveal an average  size of 17 nm. That's a 20 % range increase. Samples were the same in both cases..

    Josef Chmelar · Contipro


    Based on my experience, I would say that you have a reasonable agreement (not a very good one, but reasonable), especially considring that you use two methods with completely different principles. Also keep in mind that SAXS can be evaluated in many ways (correlation function, Brags law, or complex models) and that the obtained size does depend on the method of evaluation!

    And did you check the reproducibility of your results? If yes, what are the standard deviations of the measurements? For example, if both of your sizes have a deviation of 3 nm, then your two sizes probably do not not differ from the statistical point of view.

    I also agree with the previous reply - unless you obtained many TEM images and used image analysis for all of them, your TEM data might not be representative.



  • Saeid Davazdahemami asked a question in Herbarium:
    Can we replace herbarium samples with scanned samples of plants?

      In your opinion, what are advantages/ defects of this replacement? 

  • Lisa Corcoran added an answer in Cytokines:
    How can I induce EMT in Hep3B and HepG2 cells by TNFa and TGFb2??

    We are not seeing any differential expression of EMT markers like vimentin or E/N-Cadherin in HepG2 and Hep3B cells even after 96 hours of TGFb2 (5ng/ml) and TNFa treatment (20ng/ml, in media without FBS). Prior to cytokine addition we are giving a 12 hours of serum starvation (MEM without FBS) to the cells post which we are keeping them under cytokine pressure for 96 hours in MEM without FBS. Please suggest the correct way to go. 

    Lisa Corcoran · Vectus Biosystems

    Most indications are that TGF Beta 2 doesn't work in EMT assays but TGF Beta1 does work.

  • Gertrudis Rojas added an answer in Optical Density:
    How to calculate mass (mg/L) from optical density?

    I performed ELISA for anti-HiB IgG and IgE in patients with and without asthma, and have the optical densities. I have the optical densities of my samples but want to find mg/L. I was just wondering how to go about calculating this. I have the calibration values from the standards that came with the kit and made a graph. Attached is my excel file. Any help would be great 

    Gertrudis Rojas · Center of Molecular Immunology

    Could you add more details about your ELISA. What is coated on the plate? An what do you mean by corrected OD? If we can understand the experiment, the answers could be more precise.

  • Sabarinath Pandurengan added an answer in Optimization Algorithms:
    What are the optimization algorithms that can be used for searching results from the internet?

    For my MSc thesis I am searching results for a particular course topic from the internet. The results which are links to the materials needs to be optimized. Can anyone suggest what optimization algorithms that can be used for this purpose?

    Sabarinath Pandurengan · KLN College of Engineering

    you can try recent bio inspired algorithms like cuckoo search, firefly, flower pollination algorithms proposed by xin she yang