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  • Maria Ramsay added an answer in Victimology
    Where can I find some studies on deep repressed memories and techniques for their retrieval to the conscious surface?
    I am specifically look for any methods for the retrieval of distressful memories from childhood and any explanations as to how a travesty of some sort can severely impact the mind in subtle ways. I wish to study the profound effects a forgotten/repressed memory can have upon the actions of an individual, without the person having any conscious awareness as to the complexity and complete control it has during conscious "waking" states.
    Maria Ramsay · McGill University Health Centre


  • Doug Dykaar added an answer in Nonlinear Optics
    Does anybody have solutions on how to guide a femtosecond pulse laser by microscopy from OPA for excitation of nonlinear optical process?

    Generally speaking, the peak power density of a pulse from OPA is huge high (the OPA work with a pulse repetition rate of 1KHz ,time duration ~100fs, pulse energy ~1mJ), it may damage the objective or the sample in the focus plane.

    Doug Dykaar · DifTek Lasers, Inc.

    There are standard reflective microscope objectives:


    Presumably they can be coated for high power.

  • How can a constructivist and behaviourist approach to pedagogy contribute towards inclusive teaching and learning facilitation?

    Constructivist approach departs from the premise that learners can construct and reconstruct knowledge while behaviourist approach is more about the change of learner behaviour to inculcate learning.

    Caree Updyke · Abington Memorial Hospital

    Hi Dave I believe you have great idealism here but we can't forget these theores because these support how and why we teach the way we do. Everyone is an individual and each person learns differently. I believe in Bandura's theory of Self Efficacy and constructivism. My students are mostly adult learners and they need enthusiasm  to drive their learning. Constructivism is active learning with motivation and enthusiasm. Not all of my students learn this way.. as we are all probably aware here, the millenials are a difficult group to teach; self  centered, entitled and demanding. These students are not typically self motivated or self guided motivated learners We need to remember the osychology of the audience. While I see your point, I believe we need to remember the basics of the human psyche..

  • What is meant by transformerless inverter with virtual dc bus?

    someone please explain the concept about transformerless inverter with virtual dc bus.

  • Guannan Wang added an answer in CSCL
    Should I expect to see a distinct band after CsCl gradient purification of AAV8 virus?

    Some suggest measuring refractive index, some suggest collecting all fractions and selecting virus-rich fraction by qPCR.

    I'm wondering why after purification I do not see the formation of a distinct band, like adenovirus, after the same procedure?. 

    Guannan Wang · University of Michigan

    For my second trial, I did see a distinct and wide band after the first CsCl gradient, which unfortunately become a smear on the second CsCl gradient. It may be due to the inconsistent concentration for the two runs??? 

    John, I don't understand why you get a mixed population when packaging a small genome.  Our GOI is 2.3 kb, do you consider it a small genome to package?

    Ben, for the RI, do you take each  fraction out and measure the RI, and decide which one is in the right range. I assume you need to dialyze afterwards to get rid of the salt?

  • How can I control the agglomeration of nanoparticles in stability studies?

    I prepared chitosan nanoparticles. I am conducting stability studies at two different zone temperatures,  one is at 2 centigrade and another temperature is 25 centigrade. Nanoparticles at 25 centigrade temperature were more agglomerated.How can I prevent agglomeration during stability?

    Igor Ivan Slowing · U.S. Department of Energy, Ames Laboratory

    Adding a bit to the previous explanations and suggestions, you could modify the properties of the particles either by adding charge (using PEI for example), or by eliminating H-bond donor groups, for example by Pegylating the surface (using methoxy terminated TosOPEG).

  • Alfred Alademomi asked a question in ArcGIS
    Hypsometric analysis using ArcGIS 10

    Dear All,

    I have not been able to solve the hypsometric analysis issue using ArcGIS 10. Can anyone knidly give me the steps in using CalHypso, I have installed it in my ArcGIS 10 but it's not doing anything, it's not bringing up any suggested task to be performed.

    Better still if there is suggestion of any method to be used in performing hypsometric analysis using ArcGIS 10, I will deeply appreciate if you could kindly give this to me.

    Your kind immediate response will be deeply appreciated.


  • Kenneth Robertson added an answer in Mythology
    How can traditional mythology be visually reinterpreted to create new connections for diasporic communities?
    What is the role of myths in today's culture? How could they be reinterpreted? What is the role of myths and folklore in diasporic communities (particularly for Iranian)?
    Kenneth Robertson · Eli Lilly

    Hi Sara,

    The great Jazz pianist, Charlie Mingus, said "Making the simple complicated is commonplace; making the complicated simple, awesomely simple, that’s creativity."  I applaud your stance as first, researcher, then artist.  As a researcher, you use intentional thoughtful scientific tools to collect your thoughts, explore the background, gaher the information, to arrange your thoughts and direction.  As an artist, you will then interpret your thoughts and information into a tangible, artistic production that brings to bear all of your obvious communication and creative abilities (light, dark, color, texture, composition) to distill and convey in very simple, emotional, and intetional terms, everything you have learned.  To paraphrase the quote from Charlie Mingus, the artist in you will be able to simplify the complex for all of us, those of the diaspora and those who stand outside the diaspora experience, with the compassion to try to understand.  Just as love, hope, and dreams are universal to all mankind,  diaspora, an experience or sense of displacement, is also one of the universal experiences of man.

    1) Keep doing your research.  If you are blocked at the moment, there is a fact, a story, or a lesson that your research and your ongoing life experiences will bring, at exactly the right time, to provide a building block, an inspiration, a foundation, or a perspective that you require to complete this project.  Keep doing the work.  The pathway from potential to performance is paved with persistence and perseverance.

    2) Look at your history, your culture, your myth, and your experiences, as though examining an expensive and precious jewel.  Look from every conceivable direction, with both eyes open, ready to learn.  Are there other artistic interpreters (sculptors; musicians; actors; speakers; leaders) of the Iranian myths or culture that you admire, and from whom you might draw inspiration, different viewpoints, or fresh perspectives as you seek to share your experiences and distilled findings?

    3) After doing the research, you may have to face a monumental decision: will you insert yourself into the story, making it a first person experience and thereby welcoming others into the myth and experience, or will you draw some frame or foundation from the myth, making it a third person experience, to serve as a foundation for the message, the story you wish to show and tell the world?  

    4) As the artist, you have the opportunity and the responsibility to make the courageous decision to help us experience, to see, feel, hear, taste, and even smell the essence of the lessons you've learned, and the next steps you want us to take with you in your journey. 

  • How to implement the alignment technique for reducing construction duration in a project?
    Alignment is one of the techniques proposed by construction industry institute for reducing construction duration, so exactly how to implement the technique in all the phases of a project starting from the feasibility study to the project completion.
  • Aftab A. Chandio added an answer in Big Data
    Which programming language or languages may be considered superior when implementing algorithms for handling large data sets?

    Building efficient big data algorithms.

    Aftab A. Chandio · Chinese Academy of Sciences

    Dear Shrikant- You are correct. But the algorithms must meet the structure requirement of Map-Reduce/BSP parallel programming paradigm if you want to implement the algorithm in these paradigms.

    For example. If you implemented an algorithm in Java. You can not simply implement same algorithm in the above parallel paradigms But you need to fix your algorithm according to the structure.

  • Achille L Gaspari added an answer in Laparoscopy
    During appendectomy, what is the ideal technique to secure the base? What is the ideal suture material?

    The common methods to secure the base are:

    single endoloop (in laparoscopy) application

    double endoloop (in laparoscopy) application

    purse-string suture

    primary simple closure to bury the stump

    The common suture materials used are:

    silk; catgut; Vicryl

    What is the ideal thing to do?

    Achille L Gaspari · University of Rome Tor Vergata

    sigle o double endoloop is inaf in most cases.Endo Gia is useful with local peritonitis

  • Bhavesh Tiwari asked a question in Medicinal Plants
    Why isolation of phytochemical constituents if they show synergy in the efficacy?

    Why to go for isolation of phytochemical constituents when we know that these components act synergistically to show the enhanced efficacy?

  • Is there a way to combine or merge two orthogonal or orthonormal basis?


    This is a math question about modal shapes and orthogonal / orthonormal base

    Suppose I have some modal functions which form an orthonormal base. Let's call them W. By definition < Wi // Wj >= Kronekeri,j. It is possible to calculate an upper right triangular matrix with all the values such that the diagonal values are close to 1 and the non-diagonal values are close to 0. The under left triangular matrix is a mirror of the upper right triangular matrix so there is no use calculating that. (< Wi // Wj >=< Wj // Wi >)

    Suppose also that for high modes (i or j > 8 for example) there is an approximation that yields better results because it some numerical errors are avoided. This new base is called W' and we observe that

    < Wi // Wj > > < W'i // W'j > for i=9..inf and j=9..inf

    With that said I decides to mix the two basis and create the following:

    W_mix= [W1,..,W8,W'9,...W'inf]

    Unfortunately, I observed that < W1 // W'100 > for example doesn't give a result close to 0.

    Is there a way to create a mixed base that gives better results?

    Any good resources to share?



    Samy Geronymos · Montreal Polytechnic

    Although the approximation is simple, it would be to complicated to express it here. I will refer you to the following article.


    There is a necessity for the modal shapes to be orthogonal between them because with the approximate resolution method I'm using ( Vibration problem ). After having resolved the Eigen problem I need to resolve a system of coupled equations. The orthogonality is necessary in order to uncouple them.

    The resolution is of 10 digits so it's not a very high resolution and that is what I am trying to avoid. I want the code to be as fast as possible with a relatively low resolution. If you read the article you will understand that the numerical errors for high modes comes from the fact that the hyperbolic sine tends to infinity and since the computer can't represent infinity, the is a numerical error/illness. The approximation is used to get rid of that illness.

  • Zachary Scott asked a question in Solitary Bees
    What is the best way to track solitary bees?

    I am very interested in pollinator research and I would like to follow bees to their nest to analyze their habitat and see how far they are flying. I have looked into harmonic radar, radio telemtetry, RFID tags, maybe video tracking, following them by eye with a piece of string attached to make them more visible, or even dusting them with fluorescent paint to then come back at night with a UV lamp. I know people have successfully tracked honey bees and bumble bees through various methods, but solitary bees provide a lot more difficulty (and advanced electronic techniques will be expensive). The best luck I have had was seeing some Agapostemon bees foraging in the area and stumbling upon three of their nests by pure chance. Does anyone have any recommendations? For reference, I am a master's student still in the planning stage for next year.

  • Massih Sedigh-Rahimabadi added an answer in QMS
    "Double Slit Experiment (DSE)" a fundamental proof for "Quantum Mechanics (QM)" or an evidence for existence of "Ether"?!

    DSE has been accepted as a practical experiment for approving the duality feature of subatomic particles in QM. Each scientist has provided some series of mathematic calculation which support the wave interference pattern and show the probability of the existence of particles in different parts of the screen. In all the experiences which I have studied, we scientists are modeling the wave characteristics of the matter; they consider a serial and multiple waves which simultaneously pass through both slits and show their interference pattern.

    The big question is; why, even when there is a shot per second (Controlled double-slit electron diffraction), we consider a source of multiple waves passing the instrument?!

    Massih Sedigh-Rahimabadi · Shiraz University of Medical Sciences

    Dear Manouchehr,

    Einstein himself did not ruled out the ether (Einstein, Albert:"Dialog about Objections against the Theory of Relativity" (1918). Einstein, Albert: "Ether and the Theory of Relativity" (1920), republished in Sidelights on Relativity (Methuen, London, 1922)). But you are right the ether whit the characteristics that introduced by our ancestors has been some how ruled out.

  • Antonio Ariza added an answer in Sonication
    How can I remove DNA from bacterial crude lysates?

    Cells are lysed by sonication and further I want to remove DNA from lysates? What is the best method without damaging/reducing protein/enzyme activities? 

    Antonio Ariza · University of Oxford

    I always add DNAse to my cells prior to lysis, regardless of whether I use sonication, a cell disrupter, a french press or BugBuster. If for some reason you also need to remove RNA you can either add RNAse A on top of the DNAse 1 or just go for Benzonase, which has both DNAse and RNAse activity and works really well (though it is a bit pricey).

    Though I have heard that sonication should reduce most of the large DNA strands, I find that without DNAse it still produces somewhat viscous samples (it's the DNA released from the lysed cells that makes the cell lysate viscous). The viscosity makes it more difficult to separate the soluble fraction from the insoluble fraction using centrifugation and also clogs up any filters you might need to use before loading the soluble fraction onto a purification column.

  • Yuan Lee asked a question in Preclinical Trials
    Guys,what do you think about these obvious phenomenon in stroke?

    1) As we all known, in preclinical trials,the NMDAR antagonists show prominant neuroprotective effect. However, all of them failed in cliniacal trials.

    2) Why should t-PA should be used within 4.5h?

    3) Cortical neurons can be more resistant to hypoxic injury than microglia in a relatively short period according to our own observation.

    I am thinking that should a neuron-glia protective strategy should be more reasonable in stroke since that more and more functions exerted by glial cells have been found.

  • Shrish Shukla added an answer in Aerodyanimcs
    Can anyone give me advice on how to do solid modeling in ANSYS CFX?
    For example I want to simulate flow over a low-rise building, so how do I set my computational domain?
    Shrish Shukla · Indian Institute of Technology Delhi

    You can able to model simple kind of geometry in the cfx in you need for accurate and efficient modelling then choose solid modelling packages or  use ansys icem for meshing and geometry handling while cfx use only as a solver.

  • Paul A Rufo added an answer in Malnutrition
    Is there any cut off value for fecal markers (neopterin, calprotectin) of intestinal inflammation for children under 5?
    Fecal markers of intestinal inflammation.
    Paul A Rufo · Boston Children's Hospital

    Calprotectin and lactoferrin both nonspecific but fairly sensitive markers of GI inflammation in children and adults.  In kids, lactoferrin > 30 and calprotectin > 50 generally considered out of range.

  • Hari Priyadi asked a question in Grazing
    Can anyone help me to identify this plant?

    I found it in Kåseberga, in the grazing site close to Ales Stenar, Southern Sweden. It looks like a cactus.

  • Jaafar Jalilian added an answer in Graphene
    How can I find the binding energy for graphene layer in DFT calculation?

    Hi everybody ,this is my first question in research gate.

    The binding energy is usually expressed as difference between the total energies of products and individual reactants in DFT calculation.

    If we have covalent functionalisation 

    Jaafar Jalilian · Islamic Azad University Kermanshah Branch

    Ok, Mr Chittari is right.

    You can calculated the total energy of unit cell structures of graphene by DFT, also the total energy of one isolated C aotm.  Now, use:

    Binding Energy = Total energy of Graphene - (n x Total energy of C atom)

    where n is number of C atoms in calculated unit cell (in hexagonal unit cell there are two carbon atoms).

    Please notice that the input parameters in all calculations must be same.

  • What makes the Bezier curves so popular in applications?

    A Bézier curve is a parametric curve frequently used in computer graphics, animation, modeling, CAD, CAGD,  and many other related fields.

    Bezier curves and surfaces are curves written in Bernstein basis form; so, they are known many years ago. However, these applications are used heavily only in the last 30 years. Why? What are your thoughts and opinions?


    Bézier curves are also used in the time domain, particularly in animation and interface design, e.g., a Bézier curve can be used to specify the velocity over time of an object such as an icon moving from A to B, rather than simply moving at a fixed number of pixels per step. When animators or interface designers talk about the "physics" or "feel" of an operation, they may be referring to the particular Bézier curve used to control the velocity over time of the move in question.

    The mathematical basis for Bézier curves — the Bernstein polynomial — has been known since 1912, but its applicability to graphics was understood half a century later. Bézier curves were widely publicized in 1962 by the French engineer Pierre Bézier, who used them to design automobile bodies at Renault. The study of these curves was however first developed in 1959 by mathematician Paul de Casteljau using de Casteljau's algorithm, a numerically stable method to evaluate Bézier curves, at Citroën, another French automaker.

    Abedallah M Rababah · Jordan University of Science and Technology

    Thank you dear @Demetris for joining the discussion. Yes indeed  flexibility is one of the important features of Bezier curves besides other properties including the stability  based on the  of Bernstein polynomial basis..

  • Which characterisation techniques will provide the vacancy and surface defect present in the material?

    Based on nanomaterials.

    Jaafar Jalilian · Islamic Azad University Kermanshah Branch

    Mr Panda

    I agree with Dr Ren, XPS is a good technique. I think that its dependent on your surface strcuture, thin film, monolayer or ..., and your materials, semiconductor or metal. Generally, XPS and HRTEM are very useful.

  • Social media: Downvoting and degrading in social networks – What are the reasons? - What are the reactions?
    We have recently seen a lot of down-votings in some threads. We also saw different kinds of reactions on this phenomenon. I would like to ask a question about these reactions.

    First I assume that there are several possible reasons for downvotings: dissent – misunderstandings – misuse of buttons without knowing it– a social scientist who writes a paper about the reactions – a test carried out by RG – some technical problem, etc.

    I would like to have a discussion about the reactions on the part of researchers. We have seen calls to ban down-voters or to cancel their anonymity. Elections in democracies are anonymous and there are good reasons for this. I think most of us agree about some basic traits of democracy, the right to stay anonymous is among them. What about these basics in social media?
    András Bozsik · University of Debrecen

    Dear Piotr,

    How much time have you spent here at RG? How many down-votes have you read?
    On what kind of unconstrained evolution do you speak?
    Anonymous down-voting does stabilise nothing because the prey is mostly aware of a predator and at the moment of attack there is no anonymity. RG is a social system but your analogue with a predator-prey system is not true. Systems need feedbacks but down voting is not a right signal because is not informative and comprehensive! RG can be evolved with informative or logically perceptive feedbacks and not with treacherous anonymous quasi signals.
    I note principle of scientific activity is ambition for finding the truth. Transparency and visibility are elements of sustainability and fortunately here we should not be exposed to political pressure which may need anonymous expressions.

  • Rao Gollapudi added an answer in Hexanes
    Can anyone help with a Brine shrimp test of non-polar (Hexane) and moderate polar (dichloromethane) fractions?

    How can I do brine shrimp test (cytotoxicity) for non-polar fractions (Hexane) and dichloromethane fraction were eluted from medicinal plants? What is the best method to prepare brine solution (artificial sea water) in lab?

  • Virender Singh added an answer in Buffer
    How can I get formulation buffer devoid of therapeutic protein?

    I want to perform few studies on therapeutic protein available in market. But as control, I have to use only buffer without protein in it. Since I am not sure of exact composition of buffer, I can i remove only protein from that formulation, so as to get buffer without protein. Addition of some chemical is not good choice as that will make buffer composition different from buffer in which protein is present. Any suggestions welcome...

    Virender Singh · Indian Institute of Technology Kanpur

    thanks Adma and Steven for valuable suggestion. Yes this can be tried. Only problem is loss of some salt/excipient to filter and that may results in difference in buffer composition wrt protein formulation. 

  • Johanset Orihuela added an answer in PET Imaging
    Where can I get sample CT and PET images of brain tumors?

    I am trying to do a multimodal registration. For that I am in need of CT and PET images of brain tumors. Can someone send me a list of websites where I can get them from?

    Thanks in advance..

    Johanset Orihuela · Florida International University

    There are website and also journals that you can cite/read. Try these: