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  • Mahender Kumar added an answer in Encryption:
    Can anyone please tell me the implementation of pairing based encryption ?

    Please suggest some research or links which explained the pairing based encryption with examples.. How much time it will take to compute the one single mapping computation? 

    Mahender Kumar

    @ peter 

    thanks sir

    you are right ..  its very difficult to completely install PBC library for me ... google group have lot of information about installation .... ubuntu requires lot of packages like gmp, m4 and gtk+  but at the end its not working.... sorry iam very new in this field... please suggest me ... as its  very urgent for my research work... 

    thanks  Lu Yang

    can you please suggest  me how to install MIRACL. 

  • José Manuel Aguilar-Yañez Phd added an answer in RNA-Seq:
    Any advice on RNA on agarose gel- three bands?

    I run some plant RNA I extracted with CTAB on an agarose gel. I got two distinct, sharp bands, but there is also another slight, pale band, just above the 25S band. I don't think it's DNA, because it's too close to the 25S band. Any ideas what this may be? Do you think the RNA is intact? Is it good enough for RNA seq? (of course I will do DNAse treatment before making cDNA)

    José Manuel Aguilar-Yañez Phd

    If you want to try an easier protocol I think this might work for you: http://www.ncbi.nlm.nih.gov/pubmed/22222980

  • Marković G. Đoko added an answer in Mathematics Teaching:
    Is heuristic method an effective method for college level mathematics teaching?

    The word `Heuristic` means to discover. in this method, the students be put in the place of an independent discoverer.  The teacher sets a problem for the students and then ask them to discover the answer. Here students gets only a little help from the teacher. Students find out the solution by experiments, group discussions, or any other means. Experts say that this  method has so many positives and it develops scientific attitude. What I would like to earn from you is your valuable view points and experiences about the effectiveness of this method in the college level Mathematics teaching.

    Marković G. Đoko

    Heuristic method "in the light "of the principle of permanence is method of the future and a database of active teaching.

  • Dmitriy Likhachev added an answer in Tauc Plot:
    What is the correct band gap determined by a Tauc plot?

    I am having a Tauc plot showing two liniar segments. My question is related to the last liniar portion which is interesecting the x axis. I know the Band gap is obtained by extrapolating the last liniar segment of the graph - that going to 3.1 eV in mv graph. Normally after this portion the graphs is going in a nonliniar manner to small values. In this particular case it seems that the graph is going again in a liniar way and I can have a second BG. My question is :I am really having a second band gap at 2.6 eV (corresponding to another phase in my film) or this is not a reliable argument as the last portion of the graph (going to small energy values) is not reliable for determining the BG. Can you give any references to a better understanding of the facts?

    Dmitriy Likhachev

    Dear Petru,

    You might have some kind of sub-bandgap absorption due to defect or different crystallinity phase (like monoclinic phase of HfO2). We tried to model such behavior in our recent paper: 


  • Sanjeev Gupta asked a question in Titania:
    It is possible if structure is crystalline core and disordered/ amorphous shell its crystallite size from XRD is less than its Particle size?

    If structure like Titania having crystalline core and disordered layer or amorphous with specific surface area get decrease from 50 m2/g to 30 m2/g. definetly its particle size will increase but due to disorderness at the surface intensity of XRD will decrease and FWHM will increased so Crystallite size may be decreased. If any article anyone suggest Please give suggestion.

  • Saeideh Hosseini added an answer in Solar Cells:
    How to prepare Biosynthetic solar cells ?

    Using microbes or fungus

    Saeideh Hosseini

    you can see the attached links

    + 1 more attachment

  • Charles Francis added an answer in Gravitational Field:
    Is the non locality of the gravitational field energy a serious problem for General Relativity (GRT)?



    "Although there is no room for such a thing in the energy–

    momentum tensor T, it is clear that there are situations where a ‘disembodied’

    gravitational energy is actually playing a physical role.

    Imagine  two massive bodies (planets, say). If they are close together (and we can

    suppose that they are instantaneously at rest relative to each other), then

    there will be a (negative) gravitational potential energy contribution which

    makes the total energy, and therefore the total mass, smaller than it would

    be if they are far apart.  Ignoring much tinier energy effects,

    such as distortions of each body’s shape due to the gravitational tidal field

    of the other, we see that the total contributions from the actual energy–

    momentum tensor T will be the same whether the two bodies are close

    together or far apart. Yet, the total mass/energy will differ in the two cases,

    and this difference would be attributed to the energy in the gravitational

    field itself (in fact a negative contribution, that is more sizeable when the

    bodies are close than when they are far apart)." 


    The same problem was also rised by Thirring, Kalman and Feynman in the FGT theory, they inserted the gravitational energy in the tensor equations...

    It is a problem of paramount importance which prevents the General relativity theory from describing any motion in which the hamiltonian is time dependent or rather in case of non isolated systems, or in case of non stationary interactions between different bodies.

    The attempt to model a free falling body in a gravitational field for GRT seems impossible.

    GRT has been tested  only for static or stationary systems where there is not a net exchange of energy (excluding gravitational radiation)

    Don't we need another GRAVITATIONAL THEORY which includes the results give by GRT in order to explain with a better accuracy the simple phenomenon like the free falling of a mass in a gravitational field?

    Charles Francis

    Mozafar, this is the starting point. Either there is, or there is not a maximum signal speed. If there is, then it is necessarily the same irrespective of the motion of the object transmitting the signal. If it were not, we would merely have to accelerate the transmitter relative to ourselves to increase the speed of the signal, contradicting the notion that it is already the maximum.

    If two inertial observers define coordinates in the same way, they will both observe the same physical laws. Consequently maximum signal speed is the same for both observers.

    It can be argued that a maximum signal speed is a physical necessity. Either there is a maximum speed or there is not. If there were not, instantaneous transmission would be possible, at least in a limiting case, and the laws of physics would be very different from those we observe.

    So, yes, we do have the principle that there is a maximum invariant speed, and having established this fact, we define everything else relative to that. It is not just a matter of how we define distance from the speed of light. There is a much deeper principle which makes that definition possible.

  • Harnois Maxime added an answer in Microgrids:
    Which software is the best for the shape design in papers?

    As you know and see in electrical papers such as IEEE or SD, there are many shapes for demonstration of the concepts at papers. I want to know that often which design softwares are used for drawing shape in papers except Visio? For example I've attached a shape in microgrid area.

    Harnois Maxime

    Inkscape for 2D and Blender for 3D pictures.

    Blender for animations
    For instance: https://www.youtube.com/watch?v=RasemoYzsFA

  • Ademario Junior added an answer in Pigment Analysis:
    Which nanometer (663, 645, 650, 510 and 480 nm) gives high absorption values in spectrophotometer in pigment analysis?

    Measuring leaf pigments analysis (Chlorophyll a,b and carotenoied) by spectro photometer at different wave length (663, 645, 650, 510 and 480) gives high and low absorbance value.  How?

    Ademario Junior

    Dear Peter,

    If one does not have the live interaction, the measurement of what piece of knowledge is missing is somewhat difficult, don't you think? And the resources available today to complete the missing pieces are so much better than in the past. So, I try to nudge someone into knowledge so that he or she may be able to search for themselves.

    Sometimes I am successful with this approach. Sometimes I have to add more explanations. Sometimes the student is not outspoken enough to say that he didn't understand and the doubt stays. I try hard not to silence their questions, but I am not always so lucky. And sometimes my explanation may not be good enough, so that I have to live with this possibility and try to improve my own ability to explain.

  • Samuel Tesema Lakew added an answer in Alternative Energy:
    Could Sound energy be utilised as a source of Energy for light loads?
    I am trying to use the heavy traffic noise (on a busy highway) for street lighting or other lighter loads. but my concern is its feasibility. Any suggestions?
    Samuel Tesema Lakew

    Of course it is possible for small loads like low power lighting, smart phones and electric vehicles though the density of energy aquired is small. You need a transducer for the energy convers.

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub

    Marc: "In the case of a fully locked-in patient the patient still has the possibility to communicate by blinking or moving his eyes"

    Even if he can't communicate by blinking or moving his eyes, he can be conscious.

  • Harnois Maxime added an answer in Computational Nanotechnology:
    What is the best method to draw scientific model pictures for publication in journals?
    Scientific drawing software. What kind of software is used for the same?
    Harnois Maxime

    Inkscape for 2D and Blender for 3D pictures.

    Blender for animations
    For instance: https://www.youtube.com/watch?v=RasemoYzsFA

  • Ihsan Ates added an answer in Pulmonary Embolism:
    What is the most reliable marker in the differential diagnosis of pulmonary embolism and community-acquired pneumonia?

    Because of similar clinical manifestations and laboratory findings, differential diagnosis of pulmonary embolism and community-acquired pneumonia (CAP) is generally difficult. 

    Ihsan Ates


  • Harnois Maxime added an answer in Academic Writing:
    Which software do you use to make vector illustrations for your papers?
    Most Latex and non-Latex scientific writers are more and more concerned about the quality of the illustrations that they put in their papers. Some use Corel Draw, Inkscape, and similar drawing software, but there is an increasing number of people using the Tikz package, which is kind of a programming language for graphics in Latex (allowing to put custom mathematical formulas in your drawings).
    Harnois Maxime

    Inkscape for 2D and Blender for 3D pictures.

    Blender for animations
    For instance: https://www.youtube.com/watch?v=RasemoYzsFA

  • Seyed Hamed Moazzami Farida asked a question in Graphics:
    Graphical abstract

    Which software do scientists in biology use to design their graphical abstract?

  • Harnois Maxime added an answer in Graphic Design:
    What is the best free software that can be used to prepare a high quality graphical abstract ?

    I am looking for a good free software that can be used to draw diagrams for graphical abstracts. If you know please suggest few good free software.


    Harnois Maxime

    Inkscape for 2D and Blender for 3D pictures.

    Blender for animations
    For instance: https://www.youtube.com/watch?v=RasemoYzsFA

  • Joan Vaccaro added an answer in Domestic Violence:
    Is there a relationship between familism and acculturation in disclosure and help-seeking for domestic violence and abuse among immigrant communities?

    I am developing a thesis on the role of familism and acculturation on the disclosure and help-seeking practices of immigrant women, and I am looking to see whether familism and acculturation maybe linked

    Joan Vaccaro

     sorry, here is another article

  • Hitesh Chopra asked a question in Mesenchymal Stem Cell:
    What are the markers for rabbit PDLSc to confirm their identity by flow cytometry?

    In Human PDLSc CD 73, CD 90 and CD105 has been confirmed and supported the Dominici criteria to be called as multipotent. However, what about rabbit PDLSCs?

    these markers are absent in rabbit MSCs (Comparison of Surface Markers between Human and Rabbit Mesenchymal Stem Cells)

    Can somebody put a light on it?

  • Sourabh Aneja added an answer in Corel Draw:
    How can I make an graphic image of nanometer size in any software like corel draw ?

    graphics designers, Micromagnetics How can I make an graphic image of nanometer size in any software like corel draw ? 

    Sourabh Aneja


  • Amna Khan asked a question in Affective Learning:
    What does it mean to have a null hypothesis accepted?

    Since, in my study , two null hypothesis have been accepted out of three ;for instance, an app has no affect on learning motivation. What does it contribute? Or does it  make any difference?

  • Zabi Mir Hassani added an answer in qRT-PCR:
    Hi. how many cells would be needed for a sufficient extraction of 1 micro gram RNA?

    i need to perform qRT_PCR. does any body have any idea about how many cells I should treat and lyse?

    your answers will be appreciated.

    Zabi Mir Hassani

    thanks hamadi.
    sabine, its mda-mb-231 breast cancer cell line.it must be the same as you just said, doesnt it?

  • Mathieu Gunepin asked a question in Hormones:
    Studies indicates that wearing mouthguard can help athlete improve strength, endurance, reaction time and reduce stress. Is it based on evidence?

    Some studies indicates that wearing customfitted mouthguard helps any athlete improve strength, endurance, reaction time and reduce athletic stress. Authors explain that clenching the jaw triggers the production and release of a cascade of hormones, including cortisol, the stress hormone. Wearing customfitted mouthpiece would prevent teeth clenching and relieves pressure on the temporomandibular joint and so prevent the excessive production of hormones. As a result, the body is able to unlock its full potential. Is it based on evidence?

  • Harnois Maxime added an answer in Inkscape:
    Can anyone suggest a good tool for drawing fancy 3D device schematics, e.g. of an OFET, for publications?

    I am not a big fan of MS Office (or Inkscape for that matter), but I'd like to do a nice 3D schematic of my devices for such things as publications or my dissertation. Any suggestions, tipps and tricks that might reduce the time I spend searching on the internet are welcome!

    Harnois Maxime

    Tried Blender... I have done nice 3D OFET pictures!

  • Harnois Maxime added an answer in Inkscape:
    I would like free software to draw immunology figures like T cell or antibody for manuscript?

    I need free software for drawing immunology figures for review article?

    Harnois Maxime

    Inkscape with no doubt!

  • Harnois Maxime added an answer in Inkscape:
    Is there a software devoted to graphical abstracts?

    How do you prepare graphical abstract, schematic figures and similar extras for your papers? Is there a software with good vector graphic library of shapes?

    Besided Corel, Inkscape...

    Harnois Maxime

    Tried 3D images with Blender!

  • Dejenie A. Lakew added an answer in AIDS:
    What do you want to say bout HIV infection and AIDS ?

    December 1st is World Aids Day. HIV infection- the current situation worldwide is a conflagration for human being. HIV infection can be prevented and the epidemic can be controlled. Why does HIV infection still spread swiftly and widely in the world? Why cannot all infected persons be treated? No one takes responsible for the spreading No effective ways are for future. Where will human society go?

    Dejenie A. Lakew

    The inability of humans to cure the disease caused by HIV, to rejuvenate pancreas to be able to produce insulin to cure diabetes, are few examples that indicate where our understanding of nature stands. What we call truth is always an approximation and not exactly what it actually is and we always get closer and closer to it by observing the effects of what we call solutions to problems and we make conclusions only when what we planed is observed or accomplished, which by itself need not guarantee absoluteness of truth. Such particulars put science in a marathon of research where the end line is not yet reached. 

  • Ahmad Aizaz added an answer in Heat Exchangers:
    Is that counter flow heat exchanger better than a parallel flow heat exchanger?

    the heat transfer for counter flow heat exchanger is better than parallel flow heat exchanger?

    Ahmad Aizaz

    Yea, I also support it. Simply because, for the same temperature inlet and outlet conditions, counter flow HX is smaller in size requirements than the Parallel HX, to exchange same heat transfer rate.

  • Amna Khan asked a question in Design Research:
    Which research framework should I use and Which sampling technique should i mention?

    It is hard to select research design approach being followed in my study. Since I did not randomly select(draw) sample from a population but I randomly assigned the 100 students equally to the control and treatment groups. Is it still random sampling? As random sampling means the selection of sample from population. I did this the other way around. Since it was convenience for me to work with a certain teacher so I took her classes for further experimentation. As far as, random sampling or selection is concerned, I can not use Quasi Exp design instead I can employ Experimental Design. Since the research was conducted in natural setting(school) and the independent variables(various instruction types ; conventional and an edu app instructions) were isolated, controlled and then manipulated which are against the Experimental Design and supports only the Quasi Exp Design. So what sampling technique should I mention in methodology section? Since I have employed Quasi Exp research Framework where I did Random assignment and I worked with experimental and control group. This is a bit confusing. 

    Campbell, D.T., Stanley, J.C. (1966). Experimental and Quasi-Experimental Designs for Research. Skokie, Il: Rand McNally.

    Cohen and Manion's Book

    "Random Selection & Assignment", retrieved from

  • Bhoj R Singh added an answer in Propolis:
    Does anyone know factors that affecting optical density of bacterial concentration?

    i know the thickness and the colour of the specimen affects the optical density. Do you have any resources for factors that affecting optical density because i do some kind of experiment that evaluating antibacterial effects of propolis using its optical density and standard plate count on agar. but it turns out the result is kinda different. on agar the higher its concentration the greater its inhibition but on its optical density it makes some kind of ^ curve. 

    Thank you.

    Bhoj R Singh

    Dear Alats, The response is Yes, besides growth medium  and colour production (chromogenesis) by bacteria, shape, size and appendages of bacteria all affect the OD reading, thus it is always advised to use your own standard curves with the specified bacteria to predict the numbers of cfu on the basis of OD.