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  • Ulrich Mutze added an answer in Theoretical Physics:
    I am stuck with a complex integration given in the file attached herewith. Can any please suggest me the way to solve such integration?

    I am stuck with a complex integration given in the file attached herewith. Can any please suggest me the way to solve such integration?

    Ulrich Mutze


    confronred with the task to exaluate some definite integral of 1/x, would you insist in a 'solution free of logarithms'? This examples intends to make plausible that you condition 1 does not make any sense.

  • Ahmad Solgi added an answer in Bioeconomic Modeling:
    What are the classic control variables in farm bioeconomic models based on optimization?

    What are the classic control variables in farm bioeconomic models based on optimization? Have you some examples?

    Ahmad Solgi

    Dear Alary

    You can read these papers.

    + 2 more attachments

  • Simon Kuebler added an answer in Age Estimation:
    What is a possible method to date fluvial sediments consisting of mafic/intermediate volcanic sand?

    I would like to get age constraints on the deposition of fluvial sediments in a river deposit in the Kenya Rift. Age estimates are Mid to Late Pleistocene. The sources are mostly basaltic, trachytic and phonolitic lava flows. Quarz content is fairly low, so I'm guessing OSL won't be the method of choice. Any ideas?

    Simon Kuebler

    Dear Diego,

    Thanks for the reply, I'll look into it. The trachyte has plenty of K-feldspar so that might work.

    Best, Simon  

  • Roland Iosif Moraru added an answer in Democracy:
    What should be democracy, apart from elections?

    There is no universal agreement on the concept of democracy.

    Many political scientists agree with some realistic definitions, which describe what democracy is in the real world.

    Normative viewswhat democracy should be-- are much more diverse.

    Democracy in reality, just as democratic ideals, has changed over time. Some democratic aspirations of today's people may become part of democracy in tomorrow's real world.

    What are your views on the Ideal Democracy? What should be democracy, apart from free elections?

    Roland Iosif Moraru

    Democracy should be a state where common sense rules.

  • Marcia Gasis added an answer in Agarose Gel:
    Please, i need help in this question?

    write the steps involved in making each of the following below (note, each gel is a different concentration; therefore the amounts of the various components will differ with each). The stock solution is 50X TAE. You are making 50ml of each gel. The final concentration of TAE is 1X. a. 0.8% agarose gel b. 1.2% agarose gel

    Marcia Gasis

    Hello Mera.

    Prepare 1L of 1x TAE (to run the gel you also need 1x TAE):
    1000ml/50 (dilution factor-see above)=20ml 50xTAE + 980ml Aq.Bidest

    For the 0,8% gel: 70ml (1xTAE) x 0.8g/100ml = 0.560g agarose

    Put the agarose in an erlenmeyer flask, pour 70ml 1x TAE and stir by hand. Put the flask in a microwave oven and cook until the agarose is solved. Be careful not to overboil. Let it cool down (EtBr is temperature-sensitive) in a cool room on a stirer. Be careful, don´t let it harden. Until it is cooled down (hand warm) reassemble the gel-chamber.
    Pipette EtBr into the agarose solution (wear nitrile-gloves from now on - EtBr acts as a mutagen):

    10mg/ml = 10,000ug/ml : 0.5ug/ml (I´m not sure about this - have to check it on Monday) = 1:20,000 dilution factor.
    For 70ml agarose gel you need: 70ml : 20,000 (dilution factor) = 0.0035ml = 3.5ul EtBr stock solution

    Stir by hand and pour the solution (bubble-free) in your gel chamber. Let it harden. Pour 1x TAE in your chamber on the gel (usually there is a max label on the chamber - fill the chamber up to this label). Remove the comb carefully. Fill in your DNA. Run the gel.

    For the other calculations I would suggest that you do it and post it here or leave a message, so that I can see that you understood the steps. Is that ok?


  • Fateh Mebarek-Oudina added an answer in Tourism:
    What is the role of scientific conferences ?

    Meeting, business, tourism or others ! ...

    Fateh Mebarek-Oudina

    Dear all,

    Good day,

    "The opportunity to meet other researchers; create new networks and consolidate your exisisting network; exchange new ideas; follow the new ideas: test your research activities."  ~ Oronzio Manca


  • Mohamed El Naschie added an answer in Discovery:
    Will the 2015 Nobel Prize in physics be based on false-positive data?

    On April 30, 2011, at an American Physical Society meeting, I presented my initial findings that showed that Albert Einstein's notion of hidden variables, although not local, was indeed correct.

    In 2012, I applied my discovery of these hidden variables to the Higgs boson initial discovery and found it to be based on omitted-variable bias since the two origin variables that caused the predicted effects observed were not factored into the results (see "Assumed Higgs" link). Since the two origin variables are mutually exclusive yet can produce the same results, obtaining false-positive data from experiments based on omitted-variable bias is unavoidable (see "Tempt Destiny Experiment Results" link). In science, a discovery cannot be obtained based on false-positive data. Yet in 2013, physicists confirmed that they discovered the Higgs boson and then was awarded the same year the Noble Prize for their discovery. This all took place despite both parties being informed in 2012 of the discovery of Einstein's hidden variables which would negate the Higgs boson discovery since the Large Hadron Collider cannot detect which origin variable caused which particle collision effect which in turned caused the decay product used as evidence for their discovery.

    In the meantime, I have invited the general public to confirm if the Higgs boson discovery was or was not based on an omission error (see "How Grade School Children Can Confirm If Quantum Mechanics Is a Fundamental Theory - Class Assignment Search For First Cause" link).

    It is rumored that science self-corrects itself when a new discovery supersedes previous knowledge. If this is true then how long does it take for such a correction to take place and will the 2015 Nobel Prize in physics be given for yet another discovery based on false-positive data?

    + 2 more attachments

    Mohamed El Naschie


  • Omid Askari-Khorasgani asked a question in Matricaria:
    What is the correct terminology for Matricaria recutita grown in different regions?

    In the case of Matricaria recutita L. grown in the different regions of Isfahan, Shiraz, and Ahvaz what is the correct term for them? Ecotype, genotype or chemotype?

    I am working on the effects of salinity on their chemical compositions, and I need to use the correct terminology for them.

  • Rituparna Mohanty added an answer in Structural Equation Modeling:
    I am unable to get a good model fit in my data analysis- Structural Equation Modelling.?

    I am completely new to SEM. I have tried reducing the co-variances by checking the modification indices.  Please help me out with this problem.

    Attaching the screenshot of my model for reference.

    1. Does connecting error terms from one latent variable to error term in another give wrong results?
    2. When I add error terms to a latent variable falling under another latent variable (A second order factor), my analysis is not getting completed. Why am I getting a message on (model notes) constraints need to be added?
    Rituparna Mohanty

     Thanks for your response Sir,

    I have incorporated your comments. 

    I actually removed few variables to get a model fit, therefore a sub-construct had only one manifest variable.

    When I added error terms, I am unable to execute.

    I am getting the following error

    + 1 more attachment

  • Andrew Worsley added an answer in Electronic Structure:
    What is the radius of a free electron?

    We all know the Bohr radius and the classical electron radius.

    However no one has yet pinpointed the radius of the free electron.

    experimental data to date suggest it is less  than 10^-18 m.

    This is a crucial question to understanding electron structure

    Andrew Worsley

    The free proton radius is thought to be known quite accurately at 0.8768 x 10^-15 m.

    @Eugene,  So yes the electron has a radius and structure.

    The question is what is the radius of the free electron

    @Abhijith. Yes the orbital electron has a probability density distribution, and the averaged orbital radius is known as the Bohr radius.

    But like the proton the free  electron will have a much tighter and smaller value.

    So the question remains what is the radius of the free electron

  • Chithan C Kandaswami added an answer in Yoga:
    Is there any cure of Diabetes melitus?

    Researches in the field of Yoga claims that Diabetes can be managed through regular practice of Yoga with combination of lifestyle and diet modification. How true this claim is?

    Chithan C Kandaswami

    The potential effectiveness of yoga in the amelioration of cardiovascular disease and metabolic syndrome (a constellation of metabolic disorders including diabetes).  P. Chu, R. A. Gotink, G. Y. Yeh, S. J. Goldie, M. M. Hunink. The effectiveness of yoga in modifying risk factors for cardiovascular disease and metabolic syndrome: A systematic review and meta-analysis of randomized controlled trials. European Journal of Preventive Cardiology, 2014; DOI: 10.1177/2047487314562741  This review highlights the promising evidence of Yoga in improving metabolic attributes and impacting concrete, physiological outcomes associated with normal health. Yoga could have potential as effective therapy for cardiovascular disease and metabolic syndrome, considered to be crucial public health problems worldwide.

    A recent study showed that women who routinely practiced yoga had reduced  quantities  of the cytokine,  interleukin-6 (IL-6),  known to promote inflammation, in their blood. This action could have consequences for lowering the  level of inflammation, which normally rises owing to both normal aging and stress.  Stress, Inflammation, and Yoga Practice.  Kiecolt-Glaser, Janice K.; Christian, Lisa; Preston, Heather; More...Psychosomatic Medicine. 72(2):113-121, February/March 2010. Kiecolt-Glaser, Janice K.; Christian, Lisa; Preston, Heather; More.
    Psychosomatic Medicine. 72(2):113-121, February/March 2010.

    Yoga's Impact on Inflammation, Mood, and Fatigue in Breast Cancer Survivors: A Randomized Controlled Trial. http://jco.ascopubs.org/content/32/10/1040.full.
    Published online before print January 27, 2014, doi: 10.1200/JCO.2013.51.8860 JCO April 1, 2014 vol. 32 no. 10 1040-1049.  Cancer survivors pose an elevated risk for several chronic diseases/disorders such as diabetes and cardiovascular disease (CD) in comparisons with that of individuals without a cancer history. Chronic inflammation has been considered to be associated with a spectrum of diseases/disorders including diabetes, cancer, CD and osteoporosis. At a time point of the three-months immediately after the yoga sessions ended, the levels of three pro-inflammatory cytokines, interleukin-6 (IL-6), interleukin-1 beta (IL-1B) and tumor necrosis factor-alpha (TNF-a) were diminished in the yoga group compared to that of the non-yoga group.  

    J Altern Complement Med. 2015 Sep;21(9):530-8. doi: 10.1089/acm.2014.0044. Epub 2015 Jul 16. Regular Yoga Practice Improves Antioxidant Status, Immune Function, and Stress Hormone Releases in Young Healthy People: A Randomized, Double-Blind, Controlled Pilot Study. Lim SA, Cheong KJ. "Regular yoga practice remarkably attenuated oxidative stress and improved antioxidant levels of the body. Moreover, yoga beneficially affected stress hormone releases as well as partially improved immune function."

  • Jochen Deppe asked a question in Workflows:
    Has anybody compared the workflow and precision of different dental implant planning software packages?

    There are numerous software applications for dental implant planning. There are significant differences in the workflow. Is there any study comparing these workflows. Is there any study if there is a difference in the treatment outcome?

  • Avishag Gordon added an answer in Defense Industry:
    Can we say that the policy of militarization of Israeli is forced by its geopolitical situation?

    Israel is one of the most militarized country in the world. It is caused by experience and the fact that the country is surrounded on all sides by openly hostile countries that deny its right to exist. Israel explains that there is no other exit and policies of militarization and increase to the highest level the defense industry and defense capability is a condition for the survival of this country. That's why according to Global Peace Index Israel is one of the least peaceful country. Is Israel really has no other way out? Are the skeptics of the theory of the contract against Israel?

    Avishag Gordon


    I have to refer to Tamir's  comment as baseless information. It is information based on artificial cries for equality of rights by the Israeli Arab/Palestinians in Israel, where affirmative action already exists in many institutions. For instance, the high percent of Israeli/Arab doctors in hospitals, the high percent f Israeli/Arab pharmacists in pharmacies, Their presence in Cellular companies and cable television companies, and the growing share of Israeli Arab/Palestinians students in Israeli universities.

    I am not sure what are Libel's information sources, but I certainly recommend learning more about the actual state of affairs in Israel on this issue .

  • Leks Orlando Paculba Redoble asked a question in Cercaria:
    What method can I use to isolate a cercariae form of schistosoma japunicum from a vector snail?

    If you can suggest a journal for a method that would be much appreciated.

  • Mubashar Rehman added an answer in Targeted Drug Delivery:
    Can anyone advize how to prepare large porous particles with density of the order 0,1 g/cm3 and in micron size?

    In reasearch of targeted drug delivery in human lungs, large porous particles seem be an alternative to ensure that particles do not agglomerate and penetrate deeper into the lungs without beeing captured in the mouth/nose cavity and/or pharynx.

    Mubashar Rehman

    You want to make porous nanoparticles of drug or a porous carrier for drugs loading? Just as Dr. Sonali Dalwadi said, Spray drying is more feasible for producing porous nanoparticles. Recently, 3D printing has shown excellent nanoporous structures but it is very complex technique. If you want to prepare highly porous gold nanoparticles, please see the following paper for an interesting method.


  • Ataur Rahman asked a question in Stock Solution:
    How may I prepare 100ml Tris-Urea Buffer for protein extraction?

    I have prepared some stock solutions which are required for Tris-Urea Buffer (0.05M Tris HCl, 2% SDS, 5M Urea, 1% B-merceptoethnol). Each stock solution are about 100ml volume.

    Now I need to know which amounts would be taken from these stock solutions to make 100 ml Tris-Urea Buffer.

    Your kind advice is always appreciable.

  • Indu Tucker Sidhwani added an answer in Catalysis:
    Which is the best eco-friendly reagent for reduction ?

    We are working in the area of catalytic reduction of the double bond .Which is the best eco-friendly reagent for reduction of double bond  ? 

    Indu Tucker Sidhwani

    molecular hydrogen.I agree with Tanmoy.Moreover use of  precious metals should be avoided  as these are depleting in nature 

  • Simon Dellicour added an answer in Scripting:
    Software to compute least cost path (LCP) in raster files?

    Hello every one.

    I need a stand alone tool so that I can call from my matlab script to compute the LCP distance between two points on the raster. Is such a tool available?


    Simon Dellicour

    Hi Hamid,

    did you check the position of your points on "original.asc"? (You could have a projection problem). If you plot your raster file, also check the actual raster cell values. You can also send me your files (points and raster) if you want that I have a quick look.



  • Kshitiz Singh added an answer in TGA:
    Is it possible for any middle exons of a gene to start with ATG or end with TAG/TAA/TGA

    is it possible for any middle exons of a gene to start with ATG or end with TAG/TAA/TGA ? Shouldn't it behave as start or stop codon?

    i think that TAG / TAA / TGA / ATG might be present at any position along with the start and end positions of a gene. But can it be present at start / stop of any middle exons? 

    Suppose a middle exon contains following nucleotide seqeunce

    Case 1 : ATGaacggattat

    Case 2 : aataacggatTAG / aataacggatTGA / aataacggatTAA

    are the above cases possible? please help and if possible provide me with examples/links of such exons/Genes present.

    Kshitiz Singh

    Dear Arnav Garai,

    Yes, it is quite possible that exons may start or end by ATG, TAG, TGA or TAA because the start or end of exon do not determine the coding sequence. As you know, the coding sequence is determined by sequence of mature mRNA formed after mRNA splicing. Please, have a look at the sequence of exons of phldb1 gene at this link - http://www.ensembl.org/Homo_sapiens/Gene/Sequence?db=core;g=ENSG00000019144;r=11:118606440-118658038 .

    In this gene, you can clearly see TAG or TGA at beginning or end of exons. If you explore few more genes, you will find ATG also at beginning or end of exons..

    Best regards,


  • Tushar Ashok Kshirsagar asked a question in Humidity Sensors:
    How actually the humidity sensor works.? How can we study the humidity sensing property of materials?

    Anyone can answer

  • Stam Nicolis added an answer in Quantum Field Theory:
    Are there Lorentz invariant quantum field theories?

    The provocative question is motivated by the lack of non-perturbative regulators in quantum field theory which preserve the Lorentz symmetry. Higher order derivatives regulate the time reversal invariant sector only. Do we have to return to the idea of H. B. Nielsen about the recovery of Lorentz invariance in low energy effective theories?

    Stam Nicolis

    Janos, first of all, the putative triviality of pure φ^4 doesn't make the issue of its non-triviality, when coupled to other fields any more or less suspicious than the fact that the representation of free fields is not unique. The triviality simply means that the interaction one thinks one is adding is an illusion-that's all-a sort of coordinate artifact in the space of fields, similar in spirit to what happens, for instance, for integrable models, where the interaction is, simply, a coordinate artifact. On the other hand, in the same way that non-integrable theories are, necessarily, non-trivial, the question is, what kind of interactions with other fields can make φ^4 non-trivial. Such a question, necessarily, requires a non-perturbative framework, like, for instance, the lattice. 

    While the Standard Model may have non-perturbative issues, I think that the correct statement is that it is renormalizable in perturbation theory, so I don't think that it's useful to play with words. This means, simply, that each term of the loop expansion, when computing the contribution to a process is well-defined-it does not say anything about the convergence of the loop expansion-the two statements are, frequently, conflated. 

    For the moment, all measurements at energies up to those available seem to support the predictions made by using the perturbative expansion of the Standard Model, in particular as regards the calculation of complex QCD backgrounds, and lattice calculations about flavor physics observables start to probe non-perturbative issues quantitatively. 

    That the Standard Model is an approximate description is understood and no surprise. Whether the LHC configuration (energy and luminosity) can be sensitive to non-perturbative properties of the Standard Model isn't bad news-it would be very good news, if it turns out that way. However for this statement to be effective, the result of a specific calculation is required, in order that the search strategies be designed to select the events appropriately. Such a calculation can be obtained, precisely, using a lattice regularization or, for instance, holography-but the issue of the backgrounds requires study.  For the moment, by imposing as selection criteria perturbative calculations, everything can be accounted for-and not all of the known processes have been measured to discovery precision yet.

    It may be that it will be easier to detect perturbative effects of physics beyond the Standard Model, than it will be to detect non-perturbative effects of the Standard Model. 

  • Khaled M. A. Hassanein added an answer in Mobile Phones:
    Study of immunohistochemistry and histopathology of effect of mobile phone on brain tissue in rat?


    I need the below article. Can u plz find and send it to me for free?

    Study of immunohistochemistry and histopathology of effect of mobile phone on brain tissue in rat

    Khaled M. A. Hassanein

    dear dr

    You can see these papers



  • Leena Rao added an answer in Education Science:
    Are collaborative tech tools enough for developing collaborative skills?

    There are any number of collaborative tools (e.g., Wikis, blogs, Google Sheets/Doc, Skype) for students to use in developing their collaborative skills for group projects. But, are these tech tools enough for effectively developing collaborative skills that include interpersonal and communication skills? What are your perspectives on this issue?

    Leena Rao

    Tools have limitations. I have found them to be misused. But that would take this discussion in a different direction.

  • Rachid Beghdad added an answer in Scheduling Algorithms:
    When scheduling algorithm (token bucket) is used in wireless sensor networks, it consumes more energy as it is dynamic network, how can I reduce it?

    token bucket gives token to each node to get connected in network, to transfer data .

    when some node need to communicate in network (emergency case), where its stacked in network in other position based on token.

    i need any alternate used to consider emergency case , to rearrange the token , or suggest me with alternate algorithm which consumes less energy in energy limited environment like polar regions.

    thanks in advance

    Rachid Beghdad

    Each packet should have a field called Priority and composed of 3 bits. So, priority varies from 0 to 7 (respectivelly, from 000 to 111, in binary). Hence, the receiver node will compare its own priority to the received packet, such that the highest priority is 0.

    If its priority is higer than the one of the received packet, then, it can ignore the received packet and send its own packet.

    So, in emergency case, the node wishing to send must set its priority field to 0.

    Of course, if you want to increase the priority levels according to the network density, you can add of PRIORITY field having more than 3 bits.

    Hope this will help.

  • José Luis Andreu added an answer in Spondyloarthritis:
    What is the role of sulphasalazine in axial Spondyloarthritis?

    The Context first

    1. Per capita income in India is about US$ 1600 and due to the skewed distribution of wealth almost 80% live below this level (i.e mean income is significantly higher than the median income which is closer to $ 600)

    2. The annual cost of conventional DMARDs ranges from US$ 20-US$ 120 in India while Biologics cost about USD 6000-8000 per annum with their Biosimilar versions costing between USD 3000- 4000 per annum. Less than 3% Indian households earn enough to afford biosimilars (if they were to devote their entire income towards it) and less than 1% can afford Biologics on their own.

    3. Only about 21% of patients are covered by insurance/Govt schemes where biologicals can be considered as an option (and not all insurance schemes easily pay for the biologicals)

    4. Hence, almost 77-78% of the country (I suspect it is closer to 85%) cannot have biologic agents in their algorithm as it is well over their per capita income. This is likely to be true for over 60% of the world population.

    5. The current guidelines for managing Axial Spondyloarthropathies recommend shifting to a biologic agent (anti TNF) once we declare failure with 2 NSAIDs. The old drug Sulphasalazine has been almost made redundant in the guidelines calling it ineffective, despite numerous studies in the past showing improvement in various domains in upto half the patients. Of course, it is not a match to biologics but I suspect that its role is not so bad either (personal experience), especially when seen in the global context, respecting the economic realities.

    The Question now

    1.      Specifically in this context that covers the majority of world population, what is the role of sulphasalazine for pure axial spondyloarthitis. 

    2.      How would one manage the chronic pain (over years) juggling between NSAIDs, Sulphasalazine and steroids when the economics specifically prohibit biologics.

    José Luis Andreu

    An option for NSAIDs-refractory axial pain in Spa when you cannot afford anti-TNF therapy is zoledronic acid. We have used it in a number of patients with absolute contraindication for anti-TNF with good results. In Spain, there is generic zoledronic, much cheaper than Zometa or Aclasta.

  • Harsh Prajapati added an answer in Urban Development:
    What are the constraints when we talk about the urban development?

    What i am trying to question here is, Is it the mindset of the people that restricts the development or there is something else which does not support?

    Because specifically in India,

    Same people do not respond the way they respond in the other countries towards different kinds of spaces and towards all kind of development.

    Harsh Prajapati

    @ Anushri Tiwari,

    I am sorry but i do not accept because there are policies in india but people are too lazy to actually follow them. And same people follow policies in the other countries.

  • Reza Biria added an answer in Language Learning:
    Who are the fans of computational linguistics in EFL teaching?

    Through the study which was done by Aboulalaei (2014), the results of the pretest and post-test which served as the statistical basis for the groups and a T-test comparison of group means showed a t value of -9.648.The table of T-critical with 58 degree of freedom for .05-level shows T-critical of 1.96. The T-critical is smaller than the t observed -9.648 > 6.781. Our t value is high enough that we can safely reject the null hypothesis.
    So the researchers found that the Computer Assisted Language Learning (CALL) had a significant effect on speaking skill of Iranian EFL Learners.
    But the important part of the story is that: Is there any relationship between Computer Assisted Language Learning (CALL) and speaking skill of Iranian EFL Learners? Of course the researchers found a reasonable answer to the research question; that is, there is a reasonable relationship between CALL and Iranian EFL learners' speaking skill.
    According to the researchers' experience as computational linguists teaching and doing research in different language institutions presented important and profited opportunity to learn and teach an especial language through the computer and internet.

    Reza Biria

    Dear Mir Habib,

    It all depends on the way the writers engage the targeted participants in the process. I guess part of your concern about the relationship may be due the fact that the technological tools employed within the CALL context have not been clarified well enough.In such studies it is imperative to identify the impact of the used CALL techniques on the outcome.

    Best re4gards,

    R. Biria

  • Andrew Worsley added an answer in Electron:
    What is the speed of the electron spin assuming the classical spin model of the electron?

    The spin of the the electron is known as h/2.

    We are told that this is not the classical spin primarily because the speed of the electron would need to far exceed the speed of light.

    What is the effective speed in multiples of the speed of light that the classical model actually predicts.

    This is a very important question in the understanding th dynamics of the electron.

    Andrew Worsley

    Thank you for your answer

    Is the answer by any chance closer to 137 (alpha), and could you show me your workings

  • Roberta Symeonides added an answer in ResearchGate:
    ResearchGate iPhone app - good idea or waste of time?
    I think researchers in commute would find it an interesting way of passing the time.
    What do you think? Would you use it?
    Roberta Symeonides

    a great idea!

  • Olusegun ABAYOMI Olalere asked a question in Distillation:
    What is the latest and best method between microwave assisted distillation and supercritical extraction?

    what is the latest and best method between microwave assisted distillation and supercritical extraction?