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  • Parham Kabirifar added an answer in Heat Conduction:
    What is the relation between the C-content and cooling rates in steels?

    For low carbon steels, is the heat conduction equation is inadequate to represent the experimental cooling curves? Or does convection in weld pool region play any significant role for cooling rates in case of low carbon steel ?

    Parham Kabirifar · The Hong Kong University of Science and Technology

    any time

  • AGILAN V asked a question in Global Climate Model:
    Is there any ftp to download global climate model output??

    I'm working on downscaling. For this I need to download different global climate model outputs(Such as HadCM1, HadCM3, CGCM3). If there is any ftp to download these data please give me the link. Thanks in advance.

  • In site directed mutagenesis, is it necessary to use Quick change site-directed mutagenesis kit?

    when making a mutation in a gene by mutated primers, is it necessary to use Quick change site -directed mutagenesis kit or it can be using A master mix PCR kit with mutated primers?

    Irshad Baig · Hanyang University,Seoul,Korea

    Yes, I agree with above comment from Kai Ove. You may need not to have a separate kit for site-directed mutagenesis. You just need to have DpnI enzyme as unique comonent from this kit, required for the wild-type vector digestion. Rest of the components  is same, that are commonly being used for any  normal PCR rection and trnasformation. You may take a look at my recent pulication for more details. https://www.researchgate.net/publication/255733115_Role_of_a_highly_conserved_proline-126_in_ThDP_binding_of_Mycobacterium_tuberculosis_acetohydroxyacid_synthase


  • Andi Bowe added an answer in Academic Writing:
    Citing Wikipedia?
    While Wikipedia is more and more popular with students, professors discourage them from using it and bar them from citing it. What are reasons (to cite or) not to cite Wikipedia?
    Jul 31, 2012

    What you speak of as "correction" is actually censorship. That is what these co-called experts you talk about on wiki do routinely. i have put true story, factual history, etc. and had it removed almost immediately, with no effort to even ascertain if i have told the truth. Most media these days is owned by Rupert Murdoch's companies, and journalists have suffered thereby. Just like my research showed in the 70s how only 5 people controlled everything played on every radio station in America, now one person tells everyone else what to publish and only small independent sources are even close to being able to tell stories about what is really happening, as compared to what joe public is allowed to know. From this viewpoint wiki is not a good source if you are really seeking to see from different points of view.

  • Robin Campion added an answer in Volcanic Eruptions:
    How to retrieve volcanic SO2 from ASTER TIR?

    I want to analyze the amount of SO2 emitted from volcanic activity. I will use ASTER TIR because they provide multispectral TIR data. I read some journal that give method about that such as Campion et al 2010. But, I don't know how to do it.

    Robin Campion · Universidad Nacional Autónoma de México

    Hi Kusnadi, Apa khabar?

    It is true that a lot of the SO2 remote sensing is done using UV satellites, but IR satellites have their own advantages too. Actually they are very complementary, especially ASTER. The first thing to do is to asses if there is SO2 in your ASTER image. To do this you can apply a simple band ratio to your image (B10+B12)/(2*B11). The higher the SO2 the higher this ratio will be. Usually pixels having this ration >1 are likely to have SO2, but the exact threshold may depend on the characterisitcs of your atmosphere and ground emissivity.

    Then the second thing to do is to perform forward modeling of the radiative transfer in the atmosphere. In my 2010 paper I've used a free line-by-line code called Atmosphit, but other researchers have used MODTRAN, or whatever other code that works for the thermal infrared. You will need to get familiar with how the code works, which input files are needed etc... This will probably be the toughest step. The key parameters to take into account in the forward simulation are humidity and temperature profiles in the atmophere and plume altitude. At the end of this step you will have high resolution radiance spectra that you will need to integrate over the spectral response function of ASTER. 

    Then the third step is to invert the model. In the case of ASTER, you can retrieve the ground temperature using bands 13 and 14, which are unaffected by SO2 (but are affected by ash, so be careful on this) and then used this retrieved ground temperature to retrieve the SO2. 

    Are you interested in a specific volcano?

    Best Wishes


  • Sunil Kumar Singh added an answer in Gradient PCR:
    How can a difference between GC content in PCR primers affect PCR?

    I have a fwd primer with 37% GC content and the rev primer with 61% GC content. The Tm of the fwd primer is 55.6 C and that of the rev is 58.2 C. Upon performing gradient PCR, I saw bands at 50C and 53C but not at 52 and 54C. When I performed PCR at 50C, I did not get any bands. I am considering using DMSO to lower the Tm of the second primer, but am not sure if this could be a reason I am not getting any bands. What problems may arise from differences in GC content between primers, and could this be a reason I am getting sporadic results?

    Sunil Kumar Singh · CSIR - Institute of Himalayan Bioresource Technology

    I would suggest to use annnealing just near about your highest melting temperature of primer set 1-2 degree lower as well as higher than highest one. It works well with these type of primer sets try the 60-63 degree annealing temperature for your PCR it will work.........try it.........otherwise as suggested by John Schloendorn  you have to redesign or use alternative methods...........

  • Mohamed A. A. Mahdy added an answer in H&E Staining:
    What is the optimum time required for rat brain fixation after trans-cardiac perfusion?

    For H&E staining and immunohistochemistry studies of brain tissue, we performed trans-cardiac perfusion with 4 % formaldehyde and then post-fixing in 4% formaldehdye for 24 hours. But I could not get good sectioning, tissue separated from paraffin. Is it related with perfusion time or anything else?

    Mohamed A. A. Mahdy · Yamaguchi University

    Hi Melike

    please have a look in these discussions



  • Can someone tell me how bureaucracy in educational institutions affect management, leadership, governance please?

    Bureaucracy has advantage and disadvantage but in education institutions it is considered as a hindrance. How can it's impact on management and governance be minimized? Sometimes academic leaders complained that bureaucratic problem causes slow educational changes.

    Muhammad Maqsood Khalid · Superior University

    Dear Tareq, Works of Earley et al’s (2002), Lauglo (1997) & Elmore, R. (2000) may help you advance your research work.

  • Mohamed A. A. Mahdy added an answer in SEM Analysis:
    Is it possible to measure grain size and particle size from SEM images?

    Thanks in advance for your replies.

    Mohamed A. A. Mahdy · Yamaguchi University

    Hi Abbas

    Do you have SEM photos or you will do?

    If you have the photos you can simply use Image-J software and you just need scale bar

  • Enzai Du asked a question in Environmental Issues:
    How can you make a living as a young ecologist ?

    I see that the environmental issues is becoming so important in China. However, there are very very limited opportunities for young sicientists. How can you make a living as a young ecologist? Let's have a talk.

  • How can we check the quality of a research project?
    What are the criteria for the selection of a wonderful research project?
    Maqshoof Ahmad · University of Agriculture Faisalabad

    It is the novelty of idea, methodology to be followed, researcher's competency, and implications of results to solve the relevant problems

  • Sanda Kaufman added an answer in Counter-Terrorism:
    To what extent negotiations with the non-state actors help in counter-terrorism?

    In case of Pakistan, there are factions of society which demand that the government should negotiate with the terrorists and militant groups. To what extent it can be useful in your opinion? 

    Sanda Kaufman · Cleveland State University

    Frank, it would be helpful for the discussion to summarize these arguments here, especially since you believe they   remain valid.

  • Paul R. Yarnold added an answer in ARIMA:
    Are there good papers to model survival data using time series methods like ARIMA/ARMA etc?

    I am looking for a way to model survival data using time series methods. Basically I have 100 patient and each of them has around 10 attribute variable for each patient we have observation time let's say t which event might happen or data is censored. One way to do prediction having few information is doing Cox PH model. I am thinking about any time series model that also can handle this kind of problem.

    I appreciate your help and comment.

    Paul R. Yarnold · Optimal Data Analysis LLC

    @ Mah

    If the unit of the experimental clock is, for example, days, then weight = number of days the observation was observed.  If an observation is recorded for two days, weight = 2. If the maximum number of days is D, the weight for an observation observed for the maximum number of days is D. Observations observed for a larger time period are assigned a greater weight; observations observed for a shorter time period are assigned a smaller weight. The analysis maximizes the number of days accurately explained [1]. An observation of class = 0 with D days counts the same number of "points" (days) as an observation from class = 1 with D days. No observations are dropped, the longer an observation is observed (regardless of class category), the more it "counts". This can become an issue if all of the positive cases occur very early: in this case all of the class = 1 observations are assigned a low weight, and the analysis maximizes the accuracy of predictions for class = 0. As in any engineering application, a logical solution to such a predicament can be devised.

    Weights can be other phenomena besides time: mass, value, profit, distance, or importance, for example. Complex weights also exist, such as products, ratios, differences, sums: all theoretically defined a priori. Failure to use weights is due in part to the inability of legacy methods to handle weights, and in part to the paucity of theory used to define well-constructed class variables ("dependent" measures) and/or a priori hypotheses.

    If a phenomenon being investigated as defined by the a priori hypothesis naturally (in reality) involves weights, then an analysis that ignores these weights (fails to weight observations) is invalid. If a phenomenon does NOT naturally involve weights, then using weights is invalid.

    The introduction to the ODA book describes hypothetical applications, "from A to Z", that all involve weights [2]. Failure to use appropriate weights is one reason why legacy statistical analyses fail to explain outcomes well, and also why findings reproduce poorly...

    If you'd like an example to be posted in this thread for your application, that would be fine with me (I need an ASCII data set, space delimited, with codes for class, days, and the ten attributes, and the value "-9" assigned for any missing values). As Richard suggested, it would be interesting to contrast the different approaches mentioned in terms of accuracy, parsimony, and theoretical clarity.


    [1] http://odajournal.com/2013/09/19/optimal-data-analysis-a-general-statistical-analysis-paradigm/

    [2] Yarnold, P.R., & Soltysik, R.C. Optimal data analysis: Guidebook with software for Windows. Washington, D.C.: APA Books, 2005.

  • Maximum how much amnio acid we can able to couple without using any aggregation techniqe in Solid Phase Peptide Synthesis?

    In Solid Phase Peptide Synthesis, maximum how much length we can able to perform? somebody have did up to 32residue without used any special technique. Can anyone make me to clear.

  • Is it possible identify electrical field and Magnetic field from SEM image in SE mode?

    is it possible identify electrical field and Magnetic field from SEM image in SE mode? How?

    Vladimir Dusevich · University of Missouri - Kansas City


  • Christopher C Rout asked a question in Unconsciousness:
    In training, how can the unconsciously competent transfer skills to the unconsciously incompetent?

    The competency cycle, from unconsciously incompetent, through consciously incompetent and consciously competent to unconsciously competent implies that the senior partner (mentor) of a training relationship is attempting to impart knowledge of which he/she is unaware he/she has to someone who is unaware that the knowledge exists. Inevitably this means that the training process falls short of full skills transfer and the trainee is left to "learn" by experience (good or bad) and build up his/her own set of unconscious skills that will remain occult.

  • How can Bulletin Boards be used as a teaching methodology to 18 year old students?

    Teaching Methodology: Can this method of Bulletin Boards be used with 18 year old students and if so which is the method to be used?

    Izbullaeva Gulchehra Valerievna · Buxara State University

    мы тоже используем метод досок в учебном процессе как вид инновационных технологий. В процессе дифференционного обучения нами разработано программа использование электронных досок в колледжах как основной части непрерывного образования.   

  • AGILAN V added an answer in Meteorology:
    Where I get monthly mean of relative humidity?

    I am in need of monthly mean of relative humidity from 2000-2014 for input in OPAC model. My region is Indo-Gangetic Plain and stations are Patiala, Dehradun, Nainital, Delhi, kanpur, Varanasi & Kolkata. please suggest the place where I could get the same.

    AGILAN V · National Institute of Technology, Warangal


  • What are the possible methods to ensure that the influent and effluent temperatures of the solution in the fixed-bed adsorption remain the same?

    I am planning to investigate the effect of temperature on the adsorption capacity in the continuous fixed-bed adsorption column. Thank you. 

    B. Chandrashekhar · National Environmental Engineering Research Institute

    You can use a water jacket or any other temperature control equipment such as heating tapes with regulator around the column to control the temperature. 

  • Why electrons diffuse through only thin films ?

    It is known that in Transmission electron microscope, the electrons are diffuse through films less than 300 nm.  However, Scanning electron microscope coupled with Electron diffraction X-ray analysis, it is not diffused through  the sample.  So we can get only the surface elemental composition.  Why is it so.  Is the energy of electrons are not sufficient to pass through the thick samples.

    Vladimir Dusevich · University of Missouri - Kansas City

    There are some very useful books. They can help you to compose questions in a better way.

  • Soultana Kapiki added an answer in Cultural Tourism:
    Is the Blue Flag (eco-label) a reason to choose a tourist destination?

    I would like to know if there are studies on the tourist efficiency and ecological quality label blue flags 

    Soultana Kapiki · Alexander Technological Educational Institute of Thessaloniki

    Dear Manuel, for the efficiency of hotel enterprises awarded with an EU Eco-label, you can take a look at the conference paper: "Ecological Hospitality Management in Greece: The Case of EU Ecolabeled Hotels" downloadable from ResearchGate. It doesn't refer to the Blue Flags but you might find something useful there. The study's finding is that the Greek hotels certified with an EU eco-label are more profitable compared to the industry's averages.

    I wish you happy holidays!

  • How many insect orders are there?

    Difference of opinions exist regarding the total number of insect orders. It commonly/generally varies from 29 to 32 based on morphological/molecular/phylogenetic information. However, it is really difficult on the part of a non-specialist to follow the most accepted names of insect orders. I am looking for such a list of names of the orders of insects, which are published by authorities within last 10-12 years and accepted by the most workers.

    Bidhan Chandra Das · University of Rajshahi

    Dear Dr. Upadhyay,

    Thanks for your very prompt reply. I was in your department few years ago to attend a symposium organized by Prof. Rajendra Singh. However, can you please mention the year of last edition of the said book (A D. Imms) from where you referred.

  • How can I calculate the grain size and particle size through TEM images?

    How can I calculate the grain size through TEM images?

    Vladimir Dusevich · University of Missouri - Kansas City

    O, my...

  • Jeevani Ragupathi asked a question in Lithium Battery:
    What is alloying, conversion and displacement mechanisms in lithium battery anodes?

    i dont know ans if somebody know means tell me

  • Sundarapandian Vaidyanathan added an answer in Tea:
    What are the medicinal benefits of lemon tea?

    Some excerpts from the article: "Medicinal benefits of lemon tea" by Mala Srivastava:

    "Tea is a good calorie-free substitute for sugary beverages, according to the Harvard School of Public Health. If you add a squirt of lemon juice to your tea, it will not only enhance its flavor but will also provide multiple health benefits. For example, if you are experiencing nasal congestion, drinking lemon tea can help to decongest your blocked nose, reports the University Health Service of Rochester University.

    Vitamin C Benefits

    One fluid ounce of lemon juice contains 12 milligrams of vitamin C. Water-soluble, vitamin C helps fight free radicals -- rogue molecules that damage your DNA. Free radicals may contribute to the development of diseases such as cancer and heart disease, notes University of Maryland Medical Center. By counteracting the negative effects of free radicals, vitamin C helps decrease the risk of developing cataracts by 80 percent, according to the book "The Secret Benefits of Lemon and Honey: Secret Guides.” In addition to healing wounds, vitamin C helps maintain and repair your teeth and bones. Moreover, your body requires this antioxidant to form collagen, a protein used to build skin, blood vessels, cartilage and tendons.
    Bioflavonoid Quercetin

    Citrus fruits, such as lemon, are one of the primary dietary sources of quercetin. A flavonoid, quercetin protects the insulin-producing cells in the pancreas from the damaging effects of free radicals. In addition, quercetin has an anti-inflammatory effect, as it helps stabilize the cells that release histamine in your body. Histamines are chemicals that trigger allergic reactions. According to the American Cancer Society, quercetin can inhibit the growth of cancer cells and can help promote apoptosis, a type of cell death. Animal studies have shown that quercetin may exhibit a protective effect against certain types of cancer, especially colon cancer.

    Blood Sugar Control

    High blood sugar occurs when your body produces inadequate amounts of insulin or when it cannot utilize insulin properly. Hesperidin, a compound in lemons, can modify the function of enzymes that affect your blood sugar levels, according to a study published in the January 2010 issue of the “Journal of Clinical Biochemistry and Nutrition.” This not only shields your body from the early stages of diabetes but also helps avert diabetes complications if you already have high blood sugar. Additionally, hesperidin has cholesterol-lowering effects.
    Powerful Limonoids

    A study published in the “Journal of Nutrition” in April 2005 revealed that lemons contain compounds called limonoids that have the potential to impede the growth and development of cancer cells. Not only did limonoids decelerate the growth rate of cancer cells, but they also enhanced cancer cell death when tested against human cancer cells. The study further states that these anti-cancer agents have free-radical scavenging activities."

    Your views are welcome! Thank you - Sundar

    Sundarapandian Vaidyanathan · Vel Tech - Technical University

    In many countries, tea is taken as black tea, lemon tea etc (in hot form).

    You may also try Ice-Tea, especially Iced Lemon tea - it has a very good taste too.

    Best wishes, Sundar

  • What is the proper way to sterilize polymeric microparticles prepared for ocular drug delivery?

    I've experimented sterilization with autoclave, but the melting point of used polymer polycaprolactone is 60 ° C and so it is not suitable for my formula...and so on sterilization with filtration because I have microparticles.

    gamma radiation?

    Patitapabana Parida · National Institute of Technology Rourkela

    Nano filter like Syringe pump can remove Micron size pathogenic particles but some virus and macromolecules can pass through the filter.

    May include gamma radiation of fumigation for killing bacteria and viruses but can not remove antigenic particle if contaminated before formulation.

    Best Regards


  • Ramakrishna Sukamanchi asked a question in Spectrum:
    In FT-IR spectrum y-axis displayes as %transimttence instead of %intensity. why?

    Wavenumber and %intensity are directly related.

  • Anupam Kumar added an answer in Fuzzy:
    How can I use Genetic Algorithms on a fuzzy logic controller for tuning of PID parameters of fuzzy PD or fuzzy PI controller ?

    Hello everyone,

    Plz can anyone help me. I want to optimize fuzzy logic controller with Genetic algorithms. I am attaching my file. I have written all (code/simulation file) properly with the help of ga function which is available in MATLAB. But it's not working. If any one gets the ans plz help me. 


    Anupam Kumar · Indian Institute of Technology Roorkee

    @kiran patel: thanx

    I need help plz  provide me some PSO data in fuzzy tuning.


  • Sriraman Balaji asked a question in Cognitive Radio:
    I want to learn about the COGNITIVE RADIO from basics. Plz can you suggest some books for this?

    I am new to cognitive radio. As it looks challenging, I am interested in it. I want learn the basics of it. So anyone can suggest some books for this such that it gives good intro about it.

  • Selva Chemist (Bio) added an answer in Nails:
    How can I extract proteins/Peptides from Bio samples? Can you provide exact procedures?

    I want to extract some specific proteins from bio samples that means hair, skin nail etc., please give me exact procedure/methods or related books/articles for reference.,

    Selva Chemist (Bio) · GreyMatterResearch Foundation, India

    Dear Saraniya Bharathi,

    Its somehow difficult to extract single protein from bio samples, because it's have verity of peptides/proteins in binding form in bio sample, when we starts to ectract it, it's nature was changed because its existing in bonded aggregated form, or with other compound. so that its difficult but it's possible.,

    after remove possible unwanted things from sample, add TFA and wait for 5hrs and then you extract with diethyl ether, and by HPLC-LC-MS you cn able to separate the peptides., its common methods, for your concern i have send a msg some books and articles related to this.

    Regards R.Selva.....