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  • Subhash C. Kundu added an answer in Forgiveness:
    How much do you agree with this quotation: "The stupid neither forgive nor forget; the naive forgive and forget; the wise forgive but do not forget."?

    This quote by:  , Thomas S. Szasz (Hungarian psychiatrist and Prof. of Psychiatry Emeritus at State University of New York Health Science Center in Syracuse,1920-2012).  

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

    As far as having peace within myself, the one way I can do that is forgiving the people who have done wrong to me. It causes more stress to build up anger. Peace is more productive.

    --- Rodney King

  • James R Knaub added an answer in Basic Statistical Analysis:
    How to calculate the sample size of no. of project managers in oil & gas companies when their population is unknown?

    I have many oil and gas companies in the world I really don't know how many and I do not know how many project managers do they have and the no. varies from one company to another for example chevron could have 2000 project manager while Kuwait Oil Company may have only 40 ! so how can I calculate the sample size of the project managers in oil & gas industry?

    James R Knaub · N/A

    I also just found this: "A SHORT HISTORY OF NETWORK SAMPLING," by Monroe Sirken, a quite famous early proponent of network sampling, as I recall.

    And I found this: "Estimation in Network Populations," where it contains this comment: "Depending on the population quantity of interest, samples from network populations can be used to estimate quantities like population size..."  in case that is of interest to you.

    Both files are attached. 

    I just noticed that you have your question listed under "basic" topics, but I think this is a somewhat advanced topic. 

  • Lakkakula Satish added an answer in Somatic Embryogenesis:
    What would be the best stains in staining different development stages of somatic embryogenesis?

    type of stains

    why is they (or it) better than the others?

    Lakkakula Satish · Alagappa University

     Please find the article attached here..

  • Christopher Paredes added an answer in Molecular Dynamics Simulation:
    Conservation of angular momentum in molecular dynamics?

    According to what I have seen, many molecular dynamics simulations do not care about the conservation of angular momentum . What I can affect the thermodynamic results that the angular momentum is not conserved?

    Christopher Paredes · Universidad de La Frontera

    For example in a simulation box with periodic boundary conditions I is shown that angular momentum is not conserved(Allen and Tildesley ) and as Mr. Eugene says only preserved in a spherical symmetry.

    If the angular momentum is not conserved in a box with periodic boundary conditions the situation would not have physical meaning . However , periodic boundary conditions are used because the thermodynamic quantities not depend explicitly of angular momentum . It is the latter right?

  • Louis Brassard added an answer in Philosophy Of Science:
    Objectivity is not outside and independent of the subject. Is it that given by the mental aim toward which every intentional act of thought is headed?

    In constructivism the subject, driven by his own interests, builds actively his own concept of reality through a process of integration of multiple perspectives offered.

    Constructivism regains some concepts of positivism and neo-positivism: knowledge as an active construction of the subject, is present in most research.

    Learning is not seen only as a personal activity, but as the result of a collective dimension of interpretation of reality. New knowledge is built not only and especially on the basis of what has been gained in past experiences, but also through sharing and negotiation of meanings expressed by a "community of actors".

     Constructivism so defined, for various changes on the cultural, philosophical level and on technological research, originated as a new theoretical framework in the 70s and 80s. It stems from the collapse of the idea that knowledge can be objectively learned.

    It arises primarily as a need of abandoning cognitive HIP (Human Information Processing) that has never completely given up some of its mechanistic components of behaviorism.

    The main concepts which characterize the present constructivism are the following:

    1) knowledge is the product of an active construction of the subject,

    2) knowledge has character "located", anchored in the concrete context,

    3) knowledge takes place through particular forms of collaboration and social negotiation

     In the foreground is placed the "construction of meaning" emphasizing the activity character  not predictable of such an activity.

    Therefore, the theory of knowledge (epistemology) of constructivists postulates that knowing be the product of an active construction by the subject, closely connected to the concrete situation in which learning takes place rising from the social collaboration and interpersonal communication.

    The philosopher and cybernetic Ernst von Glasersfeld in speaking of constructivism and its philosophical reflections asserts that human knowledge continuing a "true" or "objective" representation of a world that already exists "in itself", has determined the history of Western philosophy from its beginning until today. Ensued ingenious attempts to solve a paradox, namely that to prove a certain "truth" it would be necessary to compare all knowledge with that part of the reality that it is supposed to represent; but to make this comparison, it should have access to the reality as it was before going through the operations of the subject observer. In other words, such a proof of authenticity would require a comparison between one thing that is known and another unknown.

    Already the pre-Socratics, half a millennium before Christ, knew that insurmountable paradox and provided to the school of Pirrone material for the formulation of the main arguments that all the skeptics to follow have not ceased to repeat.

    For this reason, the skepticism has always stressed the need to find an alternative theory of knowledge which should be based on the fact that

    1) knowledge is not something passively received, but something that the thinking subject constructs actively;

    2) the cognitive function is adaptive, useful to the organization of the world of experiences and not the discovery of ontological reality.

    Usually, however, skeptics declared that the reliable and true knowledge is impossible: they have decided not to change the concept of knowing.

    Paraphrasing Ernst von Glasersfeld: over the last twenty years or so, it has been recognized the influence that constructivism exercised on teaching methods aimed at encouraging the thinking subject to build, adapting on the base of experience. The cases in which this approach has been applied have given generally successful results attested by an extensive literature. But there was also an inevitable backlash, a reaction that has taken the name of constructionism arguing that the conception of language and society reflects things that have a life of their own and independent as well as the construction of individual minds. The taking of some correspondence remains a metaphysical fiction since no confirmation of that correspondence can be provided as part of experience. Constructivism is a theory of knowledge and concerns, not how much it could "exist", but just how much can be known rationally.

    Louis Brassard ·


    The image/metaphor of an ''event horizon'' is very interesting.  In physics, it is a limit for the existence of space time defining a black hole.  We can re-use this image for consciousness as a limit of what could be understood and which is ''experience'': a nexus of growth of our interaction.  I like this metaphor.

  • Anand Pai added an answer in Alloys:
    Any reference on homogenisation of 6XXX series alloy??

    Does any one know any reference to effect of "Rate of heating to homogenization temperature" on mechanical property and micro structure of 6XXX series alloy?

    Anand Pai · Manipal Institute of Technology, Manipal

    For AA 6061 alloys, Homogenization is normally carried out around 5600C(in the vicinity of solidus), held at 7-8 hours and then cooled slowly, preferably in the furnace itself, till it reaches the room temperature (takes more than 24 hours when I carried it out). The heating process is slow if it is due to natural convection. The control over rate of heating is limited if heating is done in a furnace (maintained at temperature slightly higher than 5600C), since natural convection heating depends on fluid properties (surrounding the specimen), surface area of the specimen, specific heat and thermal conductivity of the material. It seems beneficial if heating is done in more than one step till 5600C if the objective is to minimize thermal stresses.

    However, the rate of cooling may be controlled by either switching off the furnace or else reducing the furnace temperature in increments (continuous monitoring needed) till it reaches room temperature over a pre-determined period. (faster cooling by quenching would lead to inhomogeneous structure and defeat the purpose of homogenizing). 

  • Faride Badalkhani added an answer in GROMOS:
    How should I treat polar hydrogens in GROMOS FF?

    Dear all,

    I am having a question about Hydrogens in GROMOS FF. There are two Hysrogens in .atp file of GROMOS FF as follows:

    HC 1.00800 ; hydrogen bound to carbon
    H 1.00800 ; hydrogen not bound to carbon

    and all the nonbonded parameters for H are considered zero, but what about polar Hydrogens that are bounded to elements other than C (for example H in amino or amid groups)? How should I treat with these polar hydrogens?

    Kind Regards,

    Faride Badalkhani · Tarbiat Modares University


    Thanks a lot for your time and answer.



  • Alexandre Bout added an answer in Tomato:
    Does anyone know about bio-control of pests in tomato?

    I would like to know trial against  Tomato Mosaic Virus, Bacterial Wilt, white fly and H. armigera plus trials using Bt, NPV, green and white muscardine powder.Thank you

    Alexandre Bout · French National Institute for Agricultural Research


    I think this question depend on your ability to control the tomato crop production system. Always, I seen good effiency of fungi as biocontrol agent n case of high humidity... but without enough ventilation you should have pathogenic fungi like oïdium :(

    Regarding whitefly,, you can use, as Alejandra said, Encarsia formosa against Trialeurodes vaporarorium, but Eretmocerus eremicus against Bemisia tabaci. You cn also use some predatory mites as A. swirskii works well on tomato plant.

    You should think to predatory bug belonging to the Miridae familly. They are often opportunist and they eat on many prey. The most common s certainly Macrolophus pygmeus. You can add some complementary food to help maintain them on the crop without prey. One important result regarding the use of this predator is that preliminary release at step of plant nursery (plus complementary/alternative food source) help to have a good nivel of predator on the crop after.

    In some country e.g. spain, Nesidiocoris tenuis is considered as a good predator too but in other one e.g. France it is considered as a pest... This one is an ambiguous one but could be a good alternative.

  • Manoj P K added an answer in Behavioral Studies:
    How can we test that buyers are rational or irrational (heuristic) when they want to decide buy a house?

    Researchers in real estate behavior studies.

    Manoj P K · Cochin University of Science and Technology

    In the Questionnaire itself you may add a question as to what is the basis of their buying decisions. Besides, during personal discussions also (with or without using an Interview Schedule) such aspects may be discussed. At higher levels, the association between various personal /psychological attributes of buyers and their rational decision-making, if any, may be studied using suitable tools like Factor analysis, SEM Modeling etc. 

  • Lorraine Muller added an answer in Social Isolation:
    Can anyone suggest readings that challenge the belief that geographical remoteness is a disadvantage for people who live in rural or isolated areas?

    In Australia, remoteness indicators have often been used to measure 'disadvantage'. The disadvantage is rarely critically discussed in the Australian literature. Rather it is described with a range of indicators, and from my view, just taken as a given. Remoteness is one of them. I'm interested in hearing from researchers who have considered these issues in other places.

    Lorraine Muller · James Cook University

    I seem to recall recent news articles that ranked rural/remote people as being happier, despite the many negatives. I did not keep any reference to it because it was more generalist in nature, lifestyle interest rather than academic interest.

    Because I live in a rural/remote area I was interested, and it certainly would explain why we have hesitated, despite reason dictating otherwise, to move to a regional city (the big smoke of Townsville).

    Not sure if that helps, but if there were better services and opportunities, remote areas would double in population I suspect.

  • Subhash C. Kundu added an answer in Philosophy:
    Do you believe that students are your best teachers? who teach you the definition of your philosophy?

    Today is our "TEACHERS DAY". I learnt a lot from my students in my past days and is still in a stage of learning.

    My students from 44 schools are now supporting me voluntarily for carbon mapping in villages, towns and cities of my state. This is my best award. We are preparing card for each species of plants that will be released on 15th Sept. , 2015

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

    Happy Teachers' Day!

    September 5, celebrated as teachers' Day in India.

    Great Abhijit! Teachers and Students re-enforce each other. And make a great teacher!

    I was motivated from my teachers and developed my philosophy to empower next generation by teaching and research. So, I am following.

    Teacher remains every time student and learns a lot from his/her experiences and his/her students.

  • Faisel Mohammed added an answer in Word Recognition:
    How do I use Hidden Markov Model toolkit (HTK) in Handwritten Arabic text recognition?

    Hi everybody,,
    I'm currently working on Handwritten Arabic words recognition, i have built a feature matrix for each image of size 34x10, where there is 3 types of features; 8 concavity, 11 distribution and 15 gradient for a total of 34, and the 10 is the length of the image divided by the sliding window size which is 3, hence the 10.
    What i'm asking for is, how can i input this feature vector to HTK to start training HMM models with a given topology but unknown parameters, if there is an example that will be great, i have read through the HTK guide but most of it i couldn't understand, since it talks about speech recognition.
    Please guide me.
    Thank you.

    Faisel Mohammed · Baghdad University College of Science

    Hi Dear

    I hope the attached files be sufficient to the answer


  • Karnal Preeth S added an answer in Concrete:
    What is the maximum compressive strength achieved with concrete so far?

    I need to know the maximum compressive strength achieved so far with concrete. What name is given to this concrete ?

    Karnal Preeth S · Gandhigram Rural Institute

    Richard P,and cheyrey (1995) achieved the maximum compressive strength 810 mpa in reactive powder concrete,they will made evolution on concrete.

    Developments in high strength high performance cement composites from the 1970’s to date (in the US and Europe) (source doc:Proceedings of Hipermat 2012
    3 rd International Symposium on UHPC and Nanotechnology for High Performance
    Construction Materials Kassel, March 7–9, 2012)

  • Mohsen Sabouri added an answer in Electrochemical Methods:
    Is there an optimum range for CNT concentration in aqueous solutions with the aim of creating composite coatings by electrochemical methods?

    We are going to do an experimental design and need to know about the general  CNT concentration range.

    Mohsen Sabouri · Research Institute of Petroleum Industry (RIPI)

    Thank you Sergio, Rosy and Luca.

    I use MWCNT without functionalization in size of 35-50 nm.

    An aqeous electrolyte (1600 mL) with pH of about 9-10 is used for coating process at about 500V (Plasma electrolytic oxidation).

    As I undrestood, we should use 1-5 g/l MWCNT in this case.  

  • Jyoti Ashok Chavan asked a question in Cytosine:
    Can any one help me to find out detailed information about switched off genes during embryonic condition?

    During embryonic condition of twins, some genes are switched off and some are switched on. Here in this process cytosine  get attaches to the CH3 then 5- methyl cytosine will be formed. 

    Why only cytosine is attached to methyl group and forms switched off gene. Why not other nitrogen bases attaches to methyl?

    Thank you. GD

  • Narendra Narayan Hombalkar added an answer in Abdomen:
    What is the length would you place a VP shunt inside abdomen?

    In children who need an VP shunt, we have to place a long catheter inside abdomen. But if the catheter is too long, bowel strangulation may happen sometimes. Longer catheter will also increase the possibility of obstruction. How long should we place a VP shunt in children?

    Narendra Narayan Hombalkar · Government Medical College, Miraj

    I keep about 12 inch of the peritoneal tube in the abdomen. inches in the abdomen. More than the length, it is important where you place. I have done more than 100 v-p shunts. And i always put the peritoneal end in the suprahepatic space and tuck it there with a suture. this will keep the peritoneal end away from the omentum. Put your abdominal incision a little high up above the palpable margin of rt lobe of liver.

  • Soulmaz Naserli asked a question in Colonialism:
    Can anyone help me in brucella abortus electroporation?

    I want to get a construct into genome of brucella abortus, which has 500 bp homology with upstream and downstream of the gene. Brucella in log phase washed 3 times with sterile cold water. Cells were resuspended in 80µL of cold glycerol 10%. I mixed 40 μl of the electrocompetent bacteria with 10 μg of plasmid and then electroporated in a BioRad Gene Pulser at 2.5kV, 5ms, 25μF. One ml of TSB was added and the mixed was incubated at 37◦C with shaking for 6 h. The electroporation mixed was then plated on Brucella Agar containing 30μg/ml kanamycin. But unfortunately I don’t have any colony or if a colony growth, can’t be increased.

  • Kimmo Rouvari added an answer in Special and General Relativity:
    Could gravitational source provide a fixed reference frame for the speed of light measurements?

    I have wondered if a gravitational source could provide the fixed reference frame for the measurements of c? There is, at least one, experiment which could prove my hypothesis wrong, I mean an object moving relative to the center of a gravitational source, and object has a light source on it and at least two photon detectors at the same distance from the light source opposite to each other (in-line with the light source).

    Synchronized clocks (on the object) are attached to the detectors so that we can record the time when photons hit them. Let's even restrict the object's movement so that it occurs on Earth's idealized spherical surface.

    If the object moves so that the line connecting the detectors and the light source is parallel to the object's heading then according to my hypothesis there should be different times on those clocks when light from the source has first hit the detectors. I can't find an experiment (described above or equivalent) which would rule my hypothesis wrong.

    Other kind of experiments wouldn't disprove my hypothesis, would they?

    Kimmo Rouvari · N/A

    You can find more about the justification for my hypothesis (presented in the question) from the linked paper.

  • Umesh Gunarathne added an answer in Sustainable Development:
    Is there any measurement model to measure the eco tourism?

    Dear All. I am Planning to Start my Mphil. it is about Eco Tourism and the Sustainable Development. Please share any measurement model for measure the Eco tourism and Sustainable Development. Further if there is any research area in addition to that let me know.


    Umesh Gunarathne · University of Ruhuna

    Thanks Uwe

  • Jaywant Pawar asked a question in Bandages:
    Can anybody tell me the different types of waste management of pharmaceuticals from hospitals world widely?

    Waste management specifically related to expired medicines and empty vials, syringes, gloves, cottons, bandages etc?

  • Zia Urrehman asked a question in Etching:
    CVD single crystal diamond through ICP-RIE ?

    Recently i have etched CVD single crystal diamond through ICP-RIE , but after etching the diamond surface have a lot impurities and some black spots , and it was not possible to remove those impurities . any suggestion?

  • Raju Vaishya added an answer in Femoral Fractures:
    Does anyone have experience of plate augmentation (with retained intra-medullary nail) for resistant non union of femoral shaft?

    I have faced with situations where despite a good looking interlocking femoral nail, the fracture fails to unite and there is rotational instability at the # site. What are the best options for such a clinical scenario?

    Raju Vaishya · Indraprastha Apollo Hospitals

    8We retained the femoral nail and did over the top plate augmentations with bone grafting and BMP. Let's hope for the best

  • Suman Pandey added an answer in PHYLIP:
    Which are the best softwares to build structure based phylogeny tree and basics on which the the tree is built ?

    what is the best software package to built and analyze structure based phylogeny tree. I have seen PHYLIP as one of the most popular software. the answer to the question I am looking for is that for a particular function how the structures of the proteins are conserved. The protein I am working on has very less sequence identity with other proteins of the superfamily which makes sequence based alignment very tough.

    Suman Pandey · Indian Institute of Technology Bombay

    Hi Carsten and Patrice,

    For building structure based phylogeny tree by VMD, first multiseq is used for alignment and then based on rmsd TREE is built. I had blast my sequence and other proteins having less than 3.5 rmsd with my protein. took the sequences and did seq based tree by MEGA6. I compared both the trees. The neighbors to my protein were similar in both the trees. But i think i need some different approach to get a clear view of evolutionary relationships between proteins that evolve for a particular function, whether sequence is conserved or three dimensional structural fold. 

  • Yuriy Pilgun added an answer in MATLAB:
    Matlab Implementation of the famous Richardson-Lucy Deblurring Algorithm ??

    dear researchers, 

    I'm searching for a Matlab source code of the famous Richardson-Lucy Deblurring Algorithm (but not the existing in-build Matlab function).

    i would be thankful if anyone can provide me with this source code (preferably with its related reference).

    Thank you

    Yuriy Pilgun · National Taras Shevchenko University of Kyiv

    Why you don't like deconvlucy.m provided with MATLAB?

  • Smita Joshi added an answer in Human Papillomavirus (HPV):
    What is the most important factor in indicating the hpv vaccine for boys?

    which the most important factors in the indication of the vaccine and parental resistance to vaccination hpv

    Smita Joshi · Hirabai Cowasji Jehangir Medical Research Institute (HCJMRI), JCDC, Jehangir Jospital, and Prayas, Pune

    Quadrivalent HPV vaccine is approved so far in 4 or 5 countries (Australia, US, Canada, etc) for boys. High-risk HPV infection is responsible for HPV related cancers in men such as penile, anal cancers and about 40-60% oro-pharyngeal cancers. Low-risk HPV types (HPV 6, 11) are responsible for anogenital warts. So these HPV related diseases can be prevented by quadrivalent vaccine in boys. The recommended age is 11-12 years and catch-up vaccination up to 21 years. In MSM population, it is recommended even up to 26 years.  Thus HPV vaccine is not only for uncircumcised boys or boys who are HIV-infected but for all boys preferably before the onset of sexual activity.  

  • Dejenie A. Lakew added an answer in Linear Algebra:
    Is there any vector spaces which no inner product identified on it?

    inner product inidentified over  any vector spaces

    Dejenie A. Lakew · John Tyler Community College

    However C^n, is an inner product space with norm |v| := sqrt(<v,v>) as well. There are many vector spaces that do work without  inner products defined on them.The spaces of continuous functions on a non-degenerate closed interval  is a vector space which works fine without  inner product defined on it, if  length is given by the sup or max norm. At the same time you can define an inner product in terms of integrals on such spaces as well and become an inner product space. The non Hilbert Sobolev spaces are another family of such examples. 

  • Miyu Fuzawa asked a question in cDNA:
    Does RT reaction depends on the amount of RNA contained in the sample?

    I use my RNA samples for RT-qPCR. I know RT reaction has a minimum amount of RNA that can be converted to cDNA (this amount is depending on the kit we use), but I wonder if this RT efficiency is depending on the amount of RNA we have in samples. For example, if I have high concentration of RNA in my sample, most of them is converted to cDNA while only a portion is converted with low concentration of RNA. Does anyone have thoughts?

  • Gyan Chandra Chauthwani added an answer in Exergy:
    What is the difference between Gibbs free energy and Exergy concept?


    I was wondering if anyone knows the clear difference between Gibbs free energy and Exergy concept?

    Thanks in advance


    Gyan Chandra Chauthwani · Nuclear Power Corporation of India ltd.

    The internal energy U might be thought of as the energy required to create a system in the absence of changes in temperature or volume. But if the system is created in an environment of temperature T, then some of the energy can be obtained by spontaneous heat transfer from the environment to the system. The amount of this spontaneous energy transfer is TS where S is the final entropy of the system. In that case, you don't have to put in as much energy. Note that if a more disordered (higher entropy) final state is created, less work is required to create the system. The Helmholtz free energy is then a measure of the amount of energy you have to put in to create a system once the spontaneous energy transfer to the sytem from the environment is accounted for.

    The internal energy U might be thought of as the energy required to create a system in the absence of changes in temperature or volume. But as discussed in defining enthalpy, an additional amount of work PV must be done if the system is created from a very small volume in order to "create room" for the system.



  • Ramkumar Thulasiram added an answer in Machining:
    Which material is added with aluminium to improve machining parameters?

    Which material is added with aluminium to improve machining parameters.

    Ramkumar Thulasiram · Mepco Sclenk Engg. College

    Any carbide particles such as silicon carbide, boron carbide etc. to aluminium to improve machinability

  • Yaming Meng asked a question in Hepatocellular Carcinoma:
    Does anybody have the HepG2.2.15 cell line?

    HepG2.2.15 is a hepatocellular carcinoma cell line which is transformed HBV.I want do some research about the influence of HBV for hepatocellular carcinoma .However,I don't have the cell line in my lab.If anyone would like to share the cell line with me,I will be eternally grateful.