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  • Ali A R Aldallal added an answer in Drugs:
    If the same drug is given by subcutaneous and intramuscular route, which one would be absorbed faster?

    if the same drug is given by subcutaneous and intramuscular route, which one would be absorbed faster?

    reach faster Tmax?

    Ali A R Aldallal


    Absorption of intramuscular route is faster so onset of action is rapid.while absorption of subcutaneous is slow because this tissue is richly supplied by nerves but is less vascular.

    Best wishes

  • Rafik Karaman added an answer in Carbon Nanotubes:
    What are the forms of potentials that can be used for carbon nano tubes, which may be solved by using discrete nonlinear schrodinger equation?

    p.g. kivrikidis

    Rafik Karaman

    Dear Arvind,

    The potential φ can be a classical analytical formula, ranging from a very simple
    sum of two-body terms, such as the Lennard-Jones potential, which models vdW interactions, to many-body potentials for modeling metals and semiconductors, such as the Tersoff potential[31]. Invoking the Born-Oppenheimer approximation, which allows one to separate Schr¨odinger’s equation into ionic and electronic components, and further choosing to treat the ions classically due to their large mass relative to the electrons, φ may then be of an explicitly quantum nature. In this case, the electronic Schr¨odinger’s  equation may be solved with various degrees of accuracy, and the resulting charge density and electronic band structure may be used to determine the potential energy of the full system and, if needed, the forces on the ions.

    For more details, please see attached chapter.

    Hoping this will be helpful,


    + 1 more attachment

  • Sergio Kogikoski jr added an answer in Materials Science:
    In Material science we do Raman characterization Why, explain?

    Respected all, In Material science research we do Raman Characterization for samples (example SnO2/rGO). Why we have to do Raman, What we will get, what is going to be happening to the sample material (bonds etc..) while doing Raman characterization? Please ....Thank you

    Sergio Kogikoski jr

    You are not obliged to do Raman characterization, it will depends of your systems. Like in the example you gave raman is a very good spectroscopic technique since it will gave you information about the SnO2 and graphene bonds, and the vibration of it will be quite separate giving you a lot of information about the interactions of your material. You probably should read any book about spectroscopic characterization that talks about FTIR and Raman, I suggest J.M. Hollas Modern Spectroscopy. Hope it will help you!

  • Alfredo Pereira Junior added an answer in God:
    What is the origin of the laws and principles of nature?

    More precisely, "what is the origin of the regularities in nature which are represented (or purported to be represented) in our various recognized or accepted laws and principles regarding nature and natural events?" (this is H.G. Callaway's formulation of the original question). Such a philosophical question should be of interest to all scientists. 

    In classical philosophy, there are two ways of answering it:

    a) Looking for an explanation outside nature. The concept of a transcendent God, the creator of nature and its order, explicitly appeared in Thomas Aquinae (the world comes from God and returns to God), Modern philosophers and scientists. It reappeared in the Contemporary epoch as a refusal of Darwinism, and/or related to some interpretations of Quantum Theory;

    b) Looking for an explanation inside nature. Nature itself, being composed of both Form and Matter (Aristotle´s Hylomorphism) produces its order, in a process that has been currently called "self-organizing". In this view, God is not the creator of Nature, but - as in Aristotle´s concept of a First Mover - an ideal of perfection projected by natural beings.

    It is clear that in spite of Aquinae´s affiliation with Aristotle, their philosophies are in opposite position in regard to the question about the origin of nature´s order. 

    Spinoza tried to conciliate both approaches, by equating God and Nature. In this case, God is not conceived as a transcendent being who creates Nature from nothingness, but as a being who is somehow immanent to Nature.

    Plato, before Aristotle, presented a combined solution, assuming both the autonomy of natural principles (Ideas) and a Demiurge who prompts the manifestation of the principles into the world of appearances.

    There is a possible third alternative, advanced by Kant in his cognitive approach to philosophical issues: to assume that laws and principles of nature are 'a priori' forms that the human mind imposes to sensory "matter". However, this alternative is actually reducible to the others. Cognitive forms should be natural or created by God (both possibilities are compatible in Spinoza's approach). For instance, the Piagetian version of Kantism assumes that these forms are biological, deriving from processes of interaction with the physical and social environment - therefore, he was committed to the self-organizing view.

    Alfredo Pereira Junior

    Dear Edwin, I have precisely argued that God is real if and only if people feel the need for him. In this sense God is not a physical entity or a supernatural being that creates Nature. God is an entity that belongs to the domain of human social consciousness. 

  • Agostino Prástaro 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).

    Agostino Prástaro

    you continue to launch stupidities on RG ... but you do not force yourself to read where you can understand what dark matter-energy is !
    You try to be clever ... but you are a simpleton ...

  • Rizwan Ahmed Khan added an answer in Machine Learning:
    Effect of imbalanced data on machine learning


    I am working with database of facial expressions that has imbalanced data. For example there are four times more examples of expression of "happiness" then expression of "disgust". 

    I am using libsvm library to learn model. When I train SVM on imbalanced dataset I get accuracy of 45%. But when I artificially balanced the data by copy pasting expressions that are under sampled, I get an accuracy of 80%. 

    Now my questions are:

    1. Is this way of balancing the data acceptable in scientific community? 

    2. Should I report both the accuracies or just the best one? 

    3. How to explain this phenomenon?

    Thank you in advance.  

    Rizwan Ahmed Khan

    Thank you Jakob and Anastasia. I am using K-fold cross validation method. Results that I have quoted above are obtained using 10-fold cross validation technique. 

  • Antonio Devanti Bardoli added an answer in Cancer Immunotherapy:
    In cancer immunotherapy, is the anti-PD-L1 antibody really safe?
    Could anti-PD-L1 antibody stimulate autoimmune problems (the same as ant CTLA-4 antibody)?
    Antonio Devanti Bardoli


  • Jochen Wilhelm added an answer in P Value:
    Conduct this test using F dis the p-value using the F distribution. Compare the result with the t-test?

    In that example, we
    had t value = 2.66 and d.f. = 18. For the two-tailed t-test, we had p-value=
    0.0159. Let’s now conduct this test using F distribution. Write down the
    hypothesis and calculate the p-value using the F distribution. Compare the result
    with the t-test.

    Jochen Wilhelm

    But thats your homework, not mine.

    I gave you the hint that F(ν,1) = t²(ν)

    (ν is the number of degrees of freedom).

    I can give you two more hints:

    - the t-distribution follows from a normal distribution divided by a chi-squared-distribution and

    - the F-distribution follows from the ratio of two chi-squared-distributions.



  • Eric Ariel L. Salas added an answer in Satellite Image Processing:
    Suggestions for MSc thesis proposals on Satellite Image Processing, analysis, and interpretation?

    suggestions for MSc thesis proposals on Satellite Image Processing, analysis, and interpretation?

    Eric Ariel L. Salas

    Hi Ali.

    This is something that you should talk about with your adviser.  If you are working on a specific project with your adviser, then it is just appropriate to pick a topic that is somehow related to the project.  I am pretty sure your adviser could come up with ideas that the two of you will be happy to work on during the duration of your thesis.

    Good luck.

  • Prakash Malin asked a question in Malnutrition:
    Linkages between Sociology and Malnutrition?

    what is the linkages between Sociology and Malnutrition or how to link Sociology with Malnutrition?

  • F. Leyvraz added an answer in Newtonian Mechanics:
    How was the Newtonian mercury perihelion precession calculated?

    The additional perihelion precession of Mercury's orbit was considered the first confirmation of General Relativity theory. It is mainly the difference between observational data and Gravitational tugs of the other planets on mercury's orbit upon Newtonian mechanics.

    My question is how was the Newtonian effect calculated and how much are the methods used trustworthy.

    F. Leyvraz

    @ Sergey: I suggested a quartic version of Verlet, meaning a symplectic integrator of fourth order. The advantage over standard Runge-Kutta is thew absence of secular drift in conserved quantities, such as energy. But I agree that for (relatively) short simulations, it is not a major issue.

    @ Andrew: `` if Gerber had taken into account time dilation he would have got the answer spot on, in agreement with GTR''

    Perhaps. But is there any consistent way to do this? He could not do it because he lived at the wrong time, but can we make a Lorentz covariant version of his calculation, thus putting in the time dilation, as you say? I doubt it.

    In any case, it seems not to be correct that the two theories are equivalent: they give different equations, which both lead to the same precession for Mercury. But it does not lead to the same orbit. This may be unmeasurable, but it is an important point: the theories are not equivalent.

  • Maria Bettencourt Pires added an answer in Educational Systems:
    How should / could we improve the Educational System, to adapt modern times, and future generations?

    Most would agree that Education plays a fundamental role in solving many of the humanity's current problems.

    I believe in a better World.

    Mass education for all youngster can play a good role in the near future.

    Should we change our system?

    Should we act on University level?

    Should we act transversally from kindergarten, through basic education?

    I should like your valuable contributes.

    Maria Bettencourt Pires

    Downvoting is NOT needed. Downvoting is NOT scientific !

  • Jeffrey W. Alstete added an answer in Entrepreneurship Development:
    Where can i find literature regarding characteristics of entrepreneurial success?

    keywords include entrepreneurial characteristics , determinants of entrepreneurial sucess.

    Jeffrey W. Alstete

    Here is an article on the Aspects of Entrepreneurial Success.

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Purpose – Guidance from successful individuals can be valuable to prospective and nascent entrepreneurs, as well as writers and instructors in the field. This paper seeks to confirm contemporary entrepreneurship concepts, examine current perceptions, and expand the knowledge base by exploring established entrepreneurship perceptions through first-hand accounts of successful small business owners. Design/methodology/approach – This qualitative research study summarizes and analyzes interviews with 149 established entrepreneurs and small business owners regarding their perceptions on the advantages and disadvantages of their endeavors, and on providing advice to prospective new venture creators. Findings – The research revealed that entrepreneurs enjoy the independence, freedom, job satisfaction, and money, but believe the long hours, stress, responsibility, risk, and lack of company benefits are drawbacks of entrepreneurial activity. The findings largely support previous research in the field, while clarifying some of the positive and negative consequences and reporting insightful recommendations. Overall, the subjects reported that the positive aspects far outweigh the negatives in their chosen career path. Practical implications – Non-monetary features of entrepreneurial activities may be greater incentives to prospective small business starters, and success is strongly connected to thorough planning according to achievers in the field. This information can be used to encourage new business owners, guide writers of entrepreneurial advice, and inform those involved in the entrepreneurship instruction. Originality/value – The direct feedback and comments from successful entrepreneurs is valuable due to the direct nature and currency of this research, as well as the linkage to previous studies.
      Full-text · Article · Aug 2008 · Journal of Small Business and Enterprise Development
  • J.H. Martin Willison added an answer in Auxetics:
    What makes cellulose auxetic?

    What makes cellulose auxetic at the nanoscale? Does this auxetis translate to the macroscale?

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Unlike conventional (positive Poisson's ratio) materials, when auxetic (negative Poisson's ratio) materials are stretched, they expand in at least one direction at 90° to the direction of stretch. Cellulose is believed to be auxetic. To fully appreciate the auxetics of non-native (processed) cellulose, a 1D bundle of cellulose microfibrils and 2D networks of cellulose mircofibrils were stretched in a Deben micro-tester, and their molecular straining followed in-plane with Raman spectroscopy. It was found that cellulose exhibits three distinct yielding points. Also, it was found that amorphous cellulose is more auxetic than crystalline cellulose while hydrogen bonds have not yielded. The 2D network of cellulose mircofibrils rather limits auxetics of single 1D cellulose microfibrils in a network. Differences in auxetics between crystals and amorphous must arise from the extra intermolecular hydrogen bonding in crystalline cellulose and associated differences in intermolecular bonding geometry. Similarity of trends of in-plane auxetics of cellulose to the off-axis auxetics of zeolites indicates similarity of structure at the nano-scale and the possibility of combining both of these semi-crystalline materials to produce ones with photo-electro-mechanical properties. Expanded background For decades now, auxetic materials have been knowingly or unknowingly used in specific technological applications 1 . In whichever technological application that auxetic materials are used, one or a combination of properties including increased indentation resistance, increased
      Full-text · Article · Oct 2014
    J.H. Martin Willison

    Another ancient paper that could be relevant is attached here.  I think the fact that polymerization and crystallization of cellulose are linked and occur in an unusual environment creates the special properties of cellulose. Without cellulose, tall plants with intricate forms cannot exist.

  • Jeroen Goud added an answer in Identification:
    Can anyone identify these mollusk species?

    This is may a species from family Assiminidae!

    Help me to properly identify.

    + 1 more attachment

    Jeroen Goud

    We have Assiminea fasciata Benson, 1835 in the Naturalis collection from India. Could that be the species? I cannot find a picture on the internet. Ruud Bank, do you have Benson, 1835 on your bookshelf?

  • Hasnahana Chetia asked a question in RStudio:
    Using a proxy with authentication details for R or Rstudio?

    I am using R 3.2 and Rstudio in Windows 7. Since, I am using a proxy internet connection, I always get the 407 proxy authentication error. I have tried setting environment variables with my proxy details, however, it doesn't do the job. Kindly help. 

    P.S. I am a beginner, kindly provide step-wise details if possible. Thanks.

  • Ali A R Aldallal added an answer in MRSA:
    What is reverse pharmacology?

    1 establishing a molecule to combat antibiotic resistance MRSA

    Ali A R Aldallal

    Reverse pharmacology

    In the field of drug discovery, reverse pharmacology [1][2][3] also known as target base drug discovery (TDD),[4] a hypothesis is first made that modulation of the activity of a specific protein target will have beneficial therapeutic effects. Screening of chemical libraries of small molecules is then used to identify compounds that bind with high affinity to the target. The hits from these screens are then used as starting points for drug discovery. This method became popular after the sequencing of the human genome which allowed rapid cloning and synthesis of large quantities of purified proteins. This method is the most widely used in drug discovery today.[5] Differently than the classical (forward) pharmacology, with the reverse pharmacology approach in vivo efficacy of identified active (lead) compounds is usually performed in the final drug discovery stages.

  • Imre Horvath added an answer in Publication:
    Please Disapprove the hypothesis 'Very less percent of basic/significant research goes to market/industrial driven applications'?

    Sometimes we find that very significant research results do not effectively come to application platform

    Market driven research  entirely goes on different platform, and most of their significant results are not directly on public platform, but with few exceptions, however the products and services with those corporates come into the market effectively

    There is a strong need for public-private partnership, in a way to suggest the needs and priorities of the corporates to the public research system and public system carry out market driven research which goes to products/services developments by public/corporate platform 

    Imre Horvath

    Dr. Karla,

    Do you mean fundamental or pure research? If yes, then it is difficult to disprove. But, anyway, why should they 'go' to 'market/industrial driven applications'?

    Kind regards,


  • Mehdi Samie added an answer in Grain Boundaries:
    Who can help me? what is the carbide type in this pic of Hayens 188 (Co- base)?

    in this pic you see microstructure of Haynes 188 after produced of it ingot (homogenize in 1200C then water quench). incidentally this pic is for before of it rolling process.what is carbide type in grain boundary and grain? please guide me?

    Mehdi Samie

    dear Malur Srinivasan thank you so much. you give me an important information about heat treatmen of Haynes 188. i have very pleased. 

  • Md Fazlul Karim asked a question in Biological:
    What is meant by the terms “selectivity” and “sensitivity” in the context of measurement of biological chemicals.

    Is it better to have one compared to the other?

  • Vladimir Dvoryanchikov added an answer in Organic Chemistry:
    Could anyone kindly let me know the quickest way to draw the functional isomers?

    Functional Isomers can be drawn for Aldehydes, Ketones, Alcohols, Ethers, Esters and Epoxides. Also, structural isomers can be drawn for alkanes, alkenes and the above molecules. I am wondering if I can find a quick way to formulate the possible number of isomers for organic molecules. 

    I have found that symmetry of the molecules play an important role in determining the possible isomers that can be drawn. 

    Vladimir Dvoryanchikov

    It is a ready term paper for the student! :)

  • Ali A R Aldallal added an answer in PubMed:
    What's the difference between Pubmed and Medline?

    If PubMed includes Medline articles plus other things, Why do most meta-analyses -I've seen- use Medline for the search rather than the freely available PubMed?

    Ali A R Aldallal

    what is the difference between PubMed and Medline?
     by Bob Phillips
    For quite a while now I’ve been convinced that for practical, non-academic research purposes PubMed is the best primary database to use. (I’m also convinced you shouldn’t be using it unless 1. You’ve checked a summary site likewww.tripdatabase.com first or 2. Your speciality is so specialised that you’ve never found anything useful doing this in the past.) I’ve always believed that the difference between PubMed and Medline was of interface – just a different way of accessing the same stuff – but now the scales have fallen from my eyes.

     PubMed contains Medline – but also the PubMedCentral papers (full text articles deposited to promote open access) and articles before they get full MeSH tagging by the NLM team that organised the databases. In this way, PubMed is both wider, easier, fuller-text’d and quicker to access

  • John Poke asked a question in Relational Sociology:
    What the effects of colonialism, capitalism on indigenous people?


    People relations 


    Please give ideas and post journal articles

  • Mostafa El-Aasser added an answer in Photonics and Optical Communications:
    What is the range of wavelength and frequency used for photonics applications?

    range of wavelength or frequency used for photonics applications on EM spectrum.

    Mostafa El-Aasser

    Photonics applications are very broad and they involves almost the whole Electromagnetic spectrum. So many applications can be found in the wavelength range [200-1500 nm] i.e. frequency range [1500-200 THz].

  • mohammad javad Haghighatnia asked a question in Ubuntu Linux:
    How to set up "R package" on Ubuntu 15.04?

    it,s require to set up for predicting the functional protein on Ubuntu especially 15.04   

  • Julio Amador asked a question in Tradition:
    Does anybody know if there was a prolonged draught in the Sonoran Desert, around 1400 CE?

    The Hohokam Tradition of Arizona, in the US and the Trincheras Tradition of Sonora, in Mexico, seem to have disappeared at that time. As they were farmers that lived in an arid environment, enough rain was fundamental for their subsistence. A prolonged draught could have been one of the factors that prompet the social crisis of these two prehispanic cultures.

  • A. M. Al-Mukhtar added an answer in Finite Element Analysis:
    Can someone help me for the propagation of a cohesive crack in franc2d?

    I've some problem with franc2d 3.1. I want to propagate a cohesive crack, i defined the material properties and the properties of the non linear interface. when i want to propagate the fracture the program ask me the number of interaction and the precision of the solution. I insert this values and after that the program collapse.

    what i can do?
    there are some other open source software for model cohesive crack?

    Forgive me for my english.

  • Valentin Danci added an answer in Special Relativity:
    What is reason at the base of the time dilation of the atomic clocks?

    The Hafele and Keating experiment was the first proven evidence that atomic clocks  register a dilation according to the Schwarzschild solution of the GRT. Twin clocks with different  histories of motion presented between the same events "Start" and "stop" a difference in their gauges,  if at the first event "start" they were syncronized. A  daily confirmation  comes from the GPS oscillators syncronisation procedures.

    The kinetic and gravitational time dilation, which is present between the satellites and the ground bases, are directly related to the gravitational potentials and the kinetic energies per unit mass referred to the center of Earth.

    Regarding the kinetic time dilation, which was conjectured by Einstein since 1905,  it is considered a key for the experiments in the accelerators. It permits to observe processes which normally would be too fast to be detected if occurred at rest in the frame of the high energy laboratories. High energies per unit mass allow processes to slow down.

    The gravitational time dilation seems to be more complex and may look different. It comes from an Einstein's genial thought and consequence of his GR theory  according to which clocks slows down in the proximity of ponderable masses.

    Valentin Danci

    From what you say, A and B could agree in such a way that their agreement complies with a condition which is external and unrelated physically to the transformation between their systems (A, B). 

    Where is the Special Relativity theory in that? That is no longer SRT.

  • Ali A R Aldallal added an answer in Sulfonamides:
    Need some help with sulfonamide antibiotics applications and their biological target?

    how   were they discoverd 

    how do  they worand clinical application

    Ali A R Aldallal

    Appropriate use of sulfonamide antibiotics
    What are sulfonamides and how do they work?
    Sulfonamides are a group of synthetic medicines that contain the sulfonamide chemical group. As well as antibiotics,* this group includes thiazide diuretics, furosemide, acetazolamide, sulfonylureas and some COX-2 inhibitors.

    By definition sulfonamides are antimicrobials rather than antibiotics, i.e. an antibiotic is a substance produced by bacteria or fungi which have antimicrobial activity, whereas sulfonamides are synthetic.

    The only antibiotic medicine containing a sulfonamide routinely available, and subsidised, in New Zealand is sulfamethoxazole with trimethoprim (co-trimoxazole). Sulfadiazine (unsubsidised, Section 29 medicine) is occasionally used in a hospital setting.

    Sulfonamide antibiotics work by interfering with folic acid synthesis in susceptible organisms, due to their structural similarity to para-aminobenzoic acid (PABA) in bacterial cells. Folic acid is essential for nucleic acid synthesis. When used alone, sulfonamide antibiotics are bacteriostatic to susceptible organisms. However, sulfamethoxazole in combination with trimethoprim (co-trimoxazole), which acts at a different enzyme in the pathway of folic acid synthesis, is thought to be synergistic and may be bactericidal in certain cellular conditions.

  • Sayed Mohammad Tariq Zafar asked a question:
    How Basil norms will prove its effectiveness?

    How Basil norms will prove its effectiveness?