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  • Hamed Pourjavadi asked a question in Supernovae:
    Stellar feedback on the ISM?

    A massive O star has a typical luminosity of 3 x 1039 ergs s-1, a lifetime of 3 x 106 yr, a stellar-wind velocity of 5000 km s-1, and a mass- loss rate of 10-5 Ms yr-1. When it ends up as a supernova, ~5 Ms is ejected with a velocity of 5000 km s-1. How can estimate the contribution of these processes to the energy and the momentum of the ISM?

  • Raiyyan Masumdar added an answer in RTL Design:
    Where Can I learn the ways to design hardware(RTL designing) used in image processing of simple to complex algorithms?

    I am trying to implement an image fusion algorithm using wavelet transform on FPGA. I just have a vague idea of the project. But to implement a hardware design, I am unaware of the concepts that I need to know of how to accumulate the data and to process the data further as required like filtering of the image , etc. 

    Raiyyan Masumdar

    I specifically want to describe the hardware in lower-level language ( verilog )

  • Gederts Ievinsh added an answer in Botany:
    Whether the plant that grows in the mountains is resistant to all kinds of stress?

    Are these plants can be planted to crops? What are the advantages and disadvantages?

    Gederts Ievinsh

    Do you mean "oil" as reserve lipids in seeds or "oil" as an aromatic mixture of terpenoids and phenolics? In the later case, it can be thought as an induced resistence mechanism, therefore, suboptimal conditions ("stress") can increase its production.

  • Ahmad Salman Khan added an answer in Software Process:
    Which steps should be followed to integrate two different software process models to each other?

    Recently, I am working on my course project, the topic is the creation of a new hybrid software process model by integrating Scrum and Team Software Process (TSP). Integration of these two models will be based on the SEMAT Essence Kernel Framework.

    I am wondering:

    • Which steps should be followed for this integration (like determination of the roles and artifacts in these two models)?
    • What should be the criteria to decide on good sides?

    Thanks in advance!

    Ahmad Salman Khan

    First of all you should define the goal of creating hybrid model..for example a goal might be to reduce communication gap between teams or team members..or to reduce time of sprint cycle...

    after deciding the goal, you can analyse both process models and explore/ identify phases/activities suitable to achieve your goal.  

  • Maryam Khamar added an answer in OpenSim:
    How to get the interface file between opensim and matlab?

    I want to know how to get the interface between opensim and matlab when I have a file on (.osm) and I want to transfer it to matlab using s-function

    I read paper (A platform for dynamic simulation and control of movement based on OpenSim and MATLAB.

    Mansouri M1, Reinbolt JA.)

    in figure(3) he mention about interface on s-function, but I do not know how it is work , please can you help me with it

    thanks for everything

    Maryam Khamar


    I download osim and opensim matlab file but it error in Initial function callback, and error in copy file, no match file, how solve it?

  • Jamal Abo omar added an answer in Animal Science:
    Does anyone have experience with sheep In Vivo digestibility Essay?
    How can I calculate the feed unit by kg of dry matter (Unité fourragère Leroy), the gross energy (kcal/kgOM), the digestibility of energy (dE), the Digestible energy, the metabolizable energy (ME) and digestible crude protein (dCP) in vivo digestibility essay.
    Jamal Abo omar

    you should perform a digestibility trial with total feed and fecal analysis. to reach metabolizable energy content collection of urine and estimation of methane emission is also needed. Energy content of feed (gross energy, fecal energy and urine energy can be measured using bomb calorimeter.

  • Rahul Chandavarkar added an answer in Movement Therapy:
    Can anyone suggest a good approach for movement therapy for PTSD?

    I am working with a mixed group of adults with post-traumatic-stress-disorder. Since it is my first time with such group I would like to know any clinical or therapy experts what is the most appropriate way to initiate therapy with such groups and if working on the periphery is a better option rather than going to the depth of the trauma.

    Rahul Chandavarkar

    Hello Jessee, 

    Your work seems very interesting . I would like to know a bit more please,before I could make any suggestions. 

    Please do get in touch. 

    Many thanks .

  • Demetris Christopoulos added an answer in Microcephaly:
    Do you think the Zika virus leads to microcephaly?

    How good is the science linking the Vika virus to microcephaly and other neurological defects in babies?

    Demetris Christopoulos

    I am not an expert on this field, however I am deeply concerned about the periodicity of appearance of so many 'strange diseases' during last years...

  • Antoine J.H. Acke added an answer in Astronomy & Astrophysics:
    An old question that is still fresh: Is gravity a Newtonian force or Einstein space-time curvature?
    No gravitational wave was measured yet, no graviton was detected accordingly. On the other hand no space- time curvature was observable. There is no successful experiment to validate the current theories. What is the nature of the mysterious gravity? What is the velocity of this effect ?
    Antoine J.H. Acke

    Dear Parviz,

    I like to give the following comment by the news on the detection of gravitational waves.

    In Einstein's general theory of relativity (GTR) spacetime  plays an active role, it is considered as a constituent element of nature.  Paraphrasing the relativist John Archibald Wheeler: spacetime tells matter how to move; matter tells spacetime how to curve.  In the context of GTR gravitational waves are ripples in the curvature of spacetime which propagate as waves travelling out from an accelerated object.

    In gravitoelectromagnetism (GEM) spacetime plays a passive role: it is just an element of the mathematical description of nature.  The gravitational interactions between objects are explained by the mediation of the gravitational field that is considered as a constituent element of nature: matter sets up a gravitational field; the gravitational field determines how matter accelerates when placed in it .  In the context of GEM gravitational waves are fluctuations in the gravitational field which propagate as waves travelling out from an accelerated object.

    So, the physical reality of space and time is at the basis of GTR while the physical reality of the gravitational field plays that role for GEM.  I wonder whether the study of the nature of gravitational waves can contribute to answering the question:  Are space and time constituent elements of nature or are it elements of our thinking about nature?

  • Lynda Gali added an answer in Superoxides:
    Which kind of light we should use in superoxide scavenging activity to induce the reaction?

    This is the protocol we used and we did not obtain any results: Superoxide radical was generated in the PMS-NADH system containing 3 mL Tris–HCl buffer (16 mM, pH 8.0), 338 M NADH, 72 M NBT, 30 M PMS and varying concentrations of ascophyllan fractions (10–50 g/mL). The mixture prepared earlier was incubated at room temperature for 5 min and the absorbance was read at 560 nm against the blank. Inthe control, the sample was substituted with Tris–HCl buffer. Thank you for help

    Lynda Gali

    Thank you for advice 

  • Gederts Ievinsh added an answer in Crop:
    What about the dose of botanicals used for the nutrient management under field condition?

    Hello All...

    I am here to know that what is the effective dose of botanicals under field condition for the nutrient management. Please be known that many scientist have used botanical on the basis of N contents @110 kg N/ha. There is lot of confusion in the recommendation of botanicals' dose. Some where I have found 3 or 5 10 or 12.5 or 20 or 25 tonnes/ha for the same crop even in the same area and same crop.

    Experts are requested to suggest in this matter.

    Rizwan Ali Ansari

    Department of Botany

    Aligarh Muslim University

    Aligarh-202002, India

    Cell: +919412819870

    Gederts Ievinsh

    Sorry, what do you mean by "botanicals"?

    Plant-derived fertilizers, e.a. green manure?

  • Jing Zhongwei asked a question in LCD:
    How to improve IPS LCD Image sticking ?

    LG display and Sharp have done similar research but I can't get the paper

  • Rahul Chandavarkar added an answer in Mental Illness:
    What are the motivations of people with severe mental illness to enter or return to work?

    This is the topic area of my MSc research

    I will be carrying out in-depth interviews with those who have lived experience

    Rahul Chandavarkar

    Dear Jess, 

    Very interesting discussions above.

    The reasons and motivations can be multi-factorial.

    One has to consider organic and functional causes.

    MUS can be a significant cause . Secondary gain also needs to be considered .

    Would be happy to discuss this further,if you would like to please.

    Many thanks

  • Parag Sen asked a question in Gasoline Engines:
    How air-fuel ratio is controlled in direct injection gasoline engine and CI or diesel engine?

    I know that in SI engines the air-fuel ratio is controlled by the carburetor (using the throttle valves). But in case of direct injection system how the air-fuel ratio is controlled by the petrol engine? How the air-fuel ratio is controlled in CI engine?

  • Graham Peter Michael Burnett added an answer in Black Holes:
    How might one escape a Supermassive Black Hole?

    An international team of astrophysicists, including researchers from the University of Cambridge, has observed a new way for gas to escape the gravitational pull of a supermassive black hole. What is the reason? May be there is no black hole in the universe,there will be more complex object..

    + 2 more attachments

  • Suthakaran Ratnasingam asked a question in Plant Breeding:
    I intend to apply clustering and ordination techniques to analysis large scale breeding trials.

    I am really confused about which method is most appropriate for large scale plant breeding trials.

  • Rahul Chandavarkar added an answer in Implants:
    40F, post traumatic painful, unstable elbow. Treatment options please?

    Best treatment options for this challenging case and choice of implants and exposure

    + 3 more attachments

    Rahul Chandavarkar

    To manage the patient holistically in a biopsychosocial manner, would suggest you request the opinion and expertise of a Liaison Psychiatrist . I am not based in India ,otherwise would have been happy to help. Best wishes .  

  • Prabhu Srinivas Yavvari added an answer in Fungicide:
    What is mode of antibacterial action of halogenated antimicrobials?

    Hi all,

    i have come across lot many fungicides, and also bactericidal compounds which often have halogen moieties in their chemical structure. I would like to know what is the mode of action of these halogen moieties inducing the antimicrobial action.

    for example

    consider flouoroimide which has dichloromaleimide species (http://www.sigmaaldrich.com/catalog/product/sial/37039?lang=en&region=IN) which is a potent antibiotic and fungicide. i would like to know the mechanism of action of this drug. how each part of the species is involved in the bactericidal activity.

    please provide any standard references for any of such antibiotics

    Prabhu Srinivas Yavvari

    Thanks a lot Mahdieh, my interest isn't on halogen releasing compounds but particularly on non-halogen releasing halogenated compounds (like triclosan e.t.c those mentioned in page 15 of your attachment). inspite of their wide usage, too little data is known in literature. please let me know if you have any other literature.

  • Prem Baboo added an answer in MSE:
    What is the meaning of e in the UPLC-mse?

    A mass data acquisition method  provided by  Waters, called MS, what is the e represent?

    Prem Baboo

    Dear Tau Wu

     Ultra-performance liquid chromatography (UPLC) is the Recent Advances in Mass Spectrometry,Chromatography/mass spectrometry (LC/MS).UPLC/MSE; a new approach for generating molecular fragment information for biomarker structure elucidation.UPLC–MSE is one of the most versatile techniques in proteomics and metabolomics.A new approach to obtain fragmentation information in liquid chromatography/mass spectrometry (LC/MS) studies of small molecules in complex mixtures is presented using simultaneous acquisition of exact mass at high and low collision energy, MSE. LC/MS-TOF and LC/MS/MS-TOF are powerful tools for the analysis of complex mixtures, especially those for biological fluids allowing the elucidation of elemental composition and fragmentation information. In this example the composition of rat urine was studied using this new approach, allowing the structures of several endogenous components to be confirmed in one analytical run by the simultaneous acquisition of exact mass precursor and fragment ion data. The spectral data obtained using this new approach are comparable to those obtained by conventional LC/MS/MS as exemplified by the identification of endogenous metabolites present in rat urinethe last decade, proteomics and metabolomics have contributed substantially to our understanding of different diseases. Proteomics and metabolomics aims to comprehensively identify proteins and metabolites to gain insight into the cellular signaling pathways underlying disease and to discover novel biomarkers for screening, early detection and diagnosis, as well as for determining prognoses and predicting responses to specific treatments. For comprehensive analysis of cellular proteins and metabolites, analytical methods of wider dynamic range higher resolution and good sensitivity are required. Ultra performance liquid chromatography–mass spectrometryElevated Energy (UPLC–MSE) is currently one of the most versatile techniques. UPLC–MSE is an established technology in proteomics studies and is now expanding into metabolite research. MSE was used for simultaneous acquisition of precursor ion information and fragment ion data at low and high collision energy in one analytical run, providing similar information to conventional MS2. In this review, UPLC–MSE application in proteomics and metabolomics was highlighted to assess protein and metabolite changes in different diseases, including cancer, neuropsychiatric pharmacology studies from clinical trials and animal models. In addition, the future prospects for complete proteomics and metabolomics are discussed.

     A fast and high-resolution UPLC-MSE analysis was used to identify phytoplankton pigments in an ethanol extract of Porphyridium purpureum (Pp) devoid of phycobiliproteins. In a first step, 22 standard pigments were analyzed by UPLC-MSE to build a database including retention time and accurate masses of parent and fragment ions. Using this database, seven pigments or derivatives previously reported in Pp were unequivocally identified: β,β-carotene, chlorophyll a, zeaxanthin, chlorophyllide a, pheophorbide a, pheophytin a, and cryptoxanthin. Minor amounts of Divinyl chlorophyll a, a chemotaxonomic pigment marker for prochlorophytes, were also unequivocally identified using the database. Additional analysis of ionization and fragmentation patterns indicated the presence of ions that could correspond to hydroxylated derivatives of chlorophyll a and pheophytin a, produced during the ethanolic extraction, as well as previously described galactosyldiacylglycerols, the thylakoid coenzyme plastoquinone, and gracilamide B, a molecule previously reported in the red seaweed Gracillaria asiatica. These data point to UPLC-MSE as an efficient technique to identify phytoplankton pigments for which standards are available, and demonstrate its major interest as a complementary method for the structural elucidation of ionizable marine molecules.

    Please find attached herewith related articles,


    Prem Baboo

    + 2 more attachments

  • Hamed Pourjavadi asked a question in Astrophysics:
    Local thermodynamic equilibrium in stellar atmosphere?

    Estimate the ratio between the temperature scale height h = T(dT/dr)-1 and the mean free path of a hydrogen atom in the atmosphere of a star. Is local thermodynamic equilibrium a valid assumption in the stellar atmosphere? Where does it break down?

  • Hamny Hamny added an answer in Uterus:
    Why the negative control in ovary and uterus of rat was stained in IHC

    we want to detect alpha estrogen receptor in ovary and uterus of rat with IHC method. But in the result, the negative control stil stained and it he granulosa cell was not stained.

    Hamny Hamny

    thank you Ms Gundrun

    we use the same tissue as test -specimen with same protocol without primary Ab.

    For fixation, we use  4 % paraformaldehyde solution for 2 days

  • Roghayeh Valizadeh added an answer in Ruminant:
    Effects of CLA on ruminant reproduction?

    does anyone knows or worked about effects of CLA on ruminant reproduction?

    Roghayeh Valizadeh

    thank you.

  • Akram Mobaraki added an answer in Political Socialization:
    Who is a sycophant? Is sycophancy an Art?

    We see sycophants in all the fields - political, social, administrative ......

    Do you think it is an art that is harmless or something that harms the organisational culture severely.   

    What kind of sycophants are prevalent in your part of the world.

    Akram Mobaraki
    مقالات چاپ شده می خواهم درباره کتاب خودخوان و محتواسازی برای دانشگاه کتاب محور و محتوا محور مثل دانشگاه پیام نور؟؟؟؟
  • Mahnaz Shahabi asked a question in Boxing:
    Do dimensions of simulation box is optional ?

    Do dimensions of simulation box is optional for GO ?

  • Muna Yahyai asked a question in Likert Scale:
    What statistical analysis should I use for likert scale data of two different groups?

    I used a questionnaire of likert scale for two different groups of students in two universities. I am using a scale of (strongly agree, agree, neither agree or disagree, disagree, strongly disagree, not applicable which =0). The problem is the response of one group is 60 while the other group is 500.
    What statistical analysis should I use for this data?
    I really appreciate any help you can provide.

  • Govinda Sharma added an answer in Thymoma:
    My EL4 cells had a massive die-off. Any idea why?

    I've been working with the mouse thymoma line, EL4, and have had a couple occasions in which the cells have suddenly and completely died off. Is it known if these cells have a senescence limit that they reach at high passage number? Are there any other culture parameters that they are extremely sensitive to? (ie. cell density too high/low, gas exchange non-optimal, etc. I've been using RPMI1640 supplemented with pyruvate, glutamine, beta-mercapto, HEPES, FBS, pen/strep. I put them into a T-75 flask resting horizontally with 20 mL media in it...cells were seeded at 600,000/mL. There are no obvious signs of contamination, the incubator is holding 37 °C, 5% CO2, and the RH pan has been topped up regularly. Any ideas or tips are appreciated

    Govinda Sharma

    Looks like the issue was mycoplasma. I tested and they were positive. Going back to old stocks, they tested negative and seem to be growing well

  • Alan Godfrey added an answer in Postural control:
    Which data can I explore through the center of mass (CoM) displacements?

    The study of CoM is very important, mainly to investigate the coordination between posture and movement. It's an interesting device which can help us to identify, for exemple, the postural control, the postural adjustments, or the overall subject's behavior through analysis of body segments. However, how can we interpret the CoM data results? In this specific case, amplitude and speed in A/P or M/L directions.

    Alan Godfrey

    Hi Marcelo

    For ageing and pathology we use accelerometry data (instrumented testing) to examine Jerk (rate of change), Root Mean Squared (RMS - magnitude), Ellipses (area), Frequency in the 95%. Check out the work by Martina Mancini and Fay Horak in the US and my colleague Silvia Del Din for some novel with standing bout testing looking at the rate of change of those variables over time. (Combined or in separate planes of movement)

    To interpret your outcomes you need to understand the vestibular system and how it can become impaired in relation to your research question - what are your hypotheses? Once you are clear on those the outcomes will align. Furthermore there has been work done on instrumented testing within the NIH Toolbox work, Google that for more. 

    Hope that helps


  • Hesham Fathy Gadelrab added an answer in Documentation:
    Not able to remove a document. Any advice?

    I am not able to delete a document uploaded by mistake though I followed the same instructions mentioned in the site about removing a document  but nothing happen and the same document still not removed !  Not happy about this, any advice?

    Hesham Fathy Gadelrab

    Hi Dr. Othman,

    Try to use Google Chrome or Firefox browsers instead of internet explorer. It might be a technical problem with the browser itself!!

  • Ajay Padmawar added an answer in Alkaloids:
    What's the pharmaceutical activity of alkaloid?

    In general they have strong biological activity but what does it actually do when it come to pharmaceutical activity?

    Ajay Padmawar

    Dear Researcher

    Attaching list about some well known alkaloids and their pharmacological activity.

    Good Luck