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  • Rakesh kn added an answer in Planning & Management:
    Would anyone like to work on a collaborative Urban Planning paper?

    I am interested on publishing a paper relating to Urban planning and management with relation to GIS, but as young publisher i wish to join with any researcher who will be interested working with me here in Tanzania. I have been in research assistance for almost three years now working in Dar es Salaam and Tanzania in general doing variou research 

    Rakesh kn · CDM Smith India Pvt Ltd

    Not sure about able to collaborate in paper writing. But as I am involved in environmental assessment and planning of urban infrastructure projects like water supply, sanitation, effluent treatment, slums, infrastructure development etc, may be there will be some areas i can provide ideas.

    If any requirement in these fields, let me know

  • Colin A Smith added an answer in Learning:
    Should a teacher focus on 'rigorous learning' or 'learning with entertainment'?
    It has been seen that many teachers in universities have become entertainers rather than focusing mainly on value-addition and learning. A lot of time gets devoted to pleasing the students; knowing them personally; building good relations with them; and telling jokes and creating humour; the focus becomes more of good feedback than rigor. Keeping the audience motivated is good for effective teaching; but since a lot of time goes in entertainment less time remains for analysis and conceptualization. What is your preference and why?
    Colin A Smith · The University of Edinburgh

    Yes, Pedro, the point about the importance of student engagement has been continuously made in various forms throughout this discussion, but no harm in returning to it again. However, it occurs to me  from your comment that we respondents might have different visions of students - some of us are thinking of school students, ranging from the academic to the school phobic: others (as the question begins with, so perhaps my fault for writing from a  largely school perspective ) have university students in mind, who presumably by definition have some academic leanings or at least ambitions. However, there may be local/cultural variations in how students regard their teachers/ lecturers. I have had university students (usually not Scottish) who have been overly respectful in my view, simply because I am their tutor.

    Class/ teaching group sizes might also vary making a difference between close intimacy (small seminars or even smaller tutor groups) with a small group to 'working a large audience' in a large lecture theatre. The experience I do have with university teaching is with  small groups (max 15) where a mixture of humour and, I hope, rigour seems to work well and, according to feedback, mostly succeeds in engaging the students. However, i am far from flamboyant and rely to a degree on creating questions for us to explore, but maybe would need to be more flamboyant/extrovert  for a large audience.

    As so often in RG discussions (not just this one), it comes down to thinking about the actual pedagogical problems one is faced with (which always is, in some form, how to engage the students) and doing so to the best of one's ability and in line with one's own strengths.

  • Alexey Mekler added an answer in Feature Selection:
    What is an appropriate method to measure the separability of multiple clusters?

    I would like to compare two feature selection methods in an application that consists of 10 classes. In order to be independent of the classification methods (LVQ, Neural Networks, SVMs, etc ...) I would like to focus on measuring the separability of these two methods in the 10-class problem at hand. Is the Dunn's index a suitable measurement in this regard? Do you recommend any other measurements? Looking forward for your feedback. Thank you.

    Alexey Mekler · St. Petersburg State University of Telecommunication


    This our article will be helpful for you, I think.


    It is good for cases of nonlinear discrimination, when ANN for further classification is used.

  • Paul Somerfield added an answer in Coral:
    Are there any chemical exudates of corals that can harm other nearby coral?
    Are there any chemical exudates of corals that can harm other nearby coral?
    Paul Somerfield · Plymouth Marine Laboratory

    Yes, or even







  • Mark Thompson added an answer in Plasmids:
    High Plasmid yield with low 260/280 ratio ? Is there any rescue method?

    I got a yield of greater than 5 microgram/ul of my plasmid preparation but the 260/280 ratio was low i.e. 1.38 using Nanodrop. I want to use the plasmid preparation for transformation experiment in future. Is there any procedure that I can follow to decontaminate the present preparation from protein ?

    Mark Thompson · The University of Sheffield

    Sounds like there is definitely contamination in there. You should check it on an agarose gel as already suggested. If you can see the band you want, it should be OK for transformation.

  • Magda Orzechowska asked a question in Microarray:
    Software for multiple microarray platforms results comparison


    I am looking for a software allowing the user to compare the results of microarray experiments, but taking into account different platforms. I mean to compare results from i.e. Agilent and Affymetrix arrays.

    I have found MicroarrayRUs, but it supports only Affymetrix, and Illumina. 

    I will be grateful for any suggestions. 

  • Mona Ellaithi added an answer in Virus:
    What is the best PCR kits for HPV detection?

    I would like to detect human papiloma virus (all types) using PCR. I would like to know if there is anyone who has experience and knows what is the best method for detection of hpv in blood. 

    Mona Ellaithi · Ahfad University for Women

    Thank you for your answers.

    in fact I am looking for PCR kits that detected HPV in blood

  • Talitha Guittin added an answer in Genesis:
    When were the Creation accounts in Genesis 1 & 2 composed, and who by?

    I am reading Mark Smith's "The Priestly Vision of Genesis 1" (2010) and finding it very frustrating.  He is so convinced that P wrote the account in the 6th century he doesn't bother to tell us why he is so sure.  I am not much disposed to believe in P, J  JE, RJE etc etc considering the fiasco that is the story of Q.  What is the evidence?  Note that I say "composed",  not "written"?  One issue is the canonical text and its editor.  Another issue is the set of sources the editor used.  A third issue of great importance is how the editor used his sources,  and what creative freedom he allowed himself.

    Talitha Guittin · University of Strasbourg

    I couldn't agree more, Chris!

    Genesis points to the beginning, but this can never be considered independantly from its telos. We read the Genesis-story now because we hope it might give us some indication on what the meaning of our being here is all about. Ethicist read the Creation-story to discover the sens of the uniqueness of human being - we call this uniqueness imago dei (Gn 1, 26-27). The important thing here is that God confirmed the uniqueness of his relation with human beings in giving himself in the man Jesus and in sending us his Spirit. Genesis and telos are related ... and here we are again with eschatology, because, as christians, we believe our ultimate telos is eschatlogical. I am not sure I would say "it points to an end" , but rather : it points to "the last things" ... whole shelves of books have been written about ta eschata, I quite appreciate the notion of "the events by which everything else is assessed". 

    We're getting further and further from the topic of your initial question ... 

  • P K Shukla added an answer in Electrolytes:
    What is the aqueous electrolyte decomposition voltage?

    Recently, I found aqueous H2SO4 electrolyte can work under a potential window of 3 V, supporting a WO3 device for electrochromic application (Angew. Chem. Int. Ed.. doi: 10.1002/anie.201407365). However, the decomposition voltage of water is 1.2 V, so what caused the electrolyte stable under 3 V?  I hope the experts will help me!

    P K Shukla · ITS Engineering College

    I think a potential window of 3 V, for a WO3 based Electrochromic  device was reported on the basis of a CV or LSV measurements. In this case protons are intercalated in WO3 electrode and hydrogen evolution does not take place. WO3 acts as a reversible electrode for protons from an aqueous electrolyte. 

  • Alavala Rajasekhar Reddy asked a question in Filing:
    Modeller 9.13 supporting files

    can anyone please help me to get pdb_95.pir and pdb_95.bin files for modelling proteins using modeller 9.13.
    thank you

  • What exactly is the physical significance of Imaginary part of (Frequency Response Function) FRF plot?

    If I could plot both graphs i.e. real part and imaginary part of FRF obtained by taking ratio of Fourier transform of acceleration to Fourier transform of impact hammer excitation signal then I understand that magnitude of FRF plot indicates the response at certain frequency (please correct me if I am wrong), but what is imaginary part? What information I may get from imaginary part?

    Stanislav Pospisil · Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic

    Imaginary part gives you the infromation about the phase shift. 

  • Prasad Neeli added an answer in Gold Nanoparticles:
    Can gold nanoparticles oxidise when heated in air?

    Gold is considered a highly inert metal. However, when miniaturised to nano size, will it sustain its stability?

    Prasad Neeli · Council For Scientific And Industrial Research, Hyderabad, India

    Gold in nanoparticle size possess very low melting points and as a result there is a tendency of oxidation at higher temperatures above 100 C in air. Hence, it should be highly stabilized with some organic ligands or stabilizers that resist agglomeration at that particular temperature.

  • Namrata Shanu Gupta added an answer in Aerobiology:
    Can you identify these spores?
    These spores were collected using a Bio-Scan 400 (surface tape) from an indoor environment.
    Namrata Shanu Gupta · University of Calcutta

    may be species of Alternaria

  • What causes Oral Submucous Fibrosis?

    The known etiological factors for causation of Oral Submucous Fibrosis  such as as ingestion of chilies, genetic and immunologic processes, nutritional deficiencies are now ruled out. Recent trend was towards arecanut chewing habit, where Arecoline, an active alkaloid found in arecanut which stimulates fibroblasts to increase production of collagen is also now ruled out. But very recently Areca nuts have also been shown to have a high copper content, and chewing areca nuts for 5-30 minutes significantly increases soluble copper levels in oral fluids. This increased level of soluble copper supported the hypothesis as an initiating factor in individuals with Oral Submucous Fibrosis. But a recent article entitled "Estimation of copper in saliva and areca nut products and its correlation with histological grades of oral submucous fibrosis" published in Journal of Oral Pathology & Medicine concludes that "Despite high copper content in areca nut products, the observations yielded a negative correlation with different histological grades of OSF. This further raises a doubt about the copper content in areca nut as an etiological factor for this crippling disease." Then what causes Oral Submucous Fibrosis???

    Mercy Okoh · University of Benin Teaching Hospital

    Areca nut, genetic predisposition and underlying immunological component. 

  • Hom Nath Chalise asked a question in Plagiarism:
    How can we check and control the plagiarism?

    Plagiarism is the act of appropriating the literary composition of another author, or excerpts, ideas or passages, and passing the material off as one's own creation without quoting sources. In short: literary or artistic theft. Searching for plagiarisers is both difficult and time-consuming. Preventing plagiarism manually is close to impossible.

    I found its a serious problem in the developing countries. How the universities in developing countries work to control plagiarism?

  • Anuj Tripathi asked a question in Zeta Potential:
    What would be the zeta potential of polyacrylamide gel synthesized in water at different pH?

    I am looking for any article or supportive document which suggest the surface charge behaviour of polyacrylamide in water at different pH.

  • Lazar Kovačević added an answer in Viscosity:
    Can you make a clear differentiation between rheocasting and thixocasting processes?

    The rheocasting is a process of creating a semi-solid slurry followed by its pushing into a metal mold for freezing. In thixocasting, the slurry freezes to fully solid phase which is again heated in semi-solid region to achieve viscosity and pushed into the mold.

    Lazar Kovačević · University of Novi Sad

    To my understanding difference is in processing route. In the case of rheocasting semisolid state is obtained by cooling from liquid temperature, while for thixocasting one uses preprepared billets and obtains slurry by simply heating the billet (usually by induction heater).

    Therefore, by using thixocasting route, initial investment is lowered and one does not need to think about how to obtain spheroidal solid phase (strict process control is essential). On the other hand, it involves intermediate solidification step/billet supplier and is therefore more expensive.

  • Is 16kb big in terms of plasmid construct?

    I've had some problems transforming my 16kb plasmid in competent bacteria using the heat shock/chemical method. Should I be using electroporation instead of heat shock?

    And if my plan is to then transfect the plasmid into a mammalian cell line to overexpress a particular protein of interest (Mw = 400kDa), are there any steps which I should be aware of in order to get maximum expression into conditioned media?

    Jing Yang Tee · Griffith University

    @Jonathan: I'm transforming the intact plasmid. I have tried JM109 and OneShot cells.

    For the transfection part, I'm planning to use HEK293T and purify the secreted protein from the medium. Will electroporation (e.g. Amaxa Nucleofector) increase the efficiency?

  • How can I calculate computational complexity of Imperialist Competitive Algorithm (ICA) ?

    I want to calculate computational complexity of each step in Imperialist Competitive Algorithm (ICA).

    Neda Manavizadeh · University of Tehran

    you can follow Mr. Atashpaz's works or papers:

    Esmaeil Atashpaz Gargari
    Department of Electrical and Computer Engineering Texas A&M University, College Station, TX, USA
    Pattern Recognition, Proteomics, Computational Biology, Next Generation Sequencing, Optimization


  • What happens if we reverse the terminals of Riemann-Liouville fractional derivatives ?

    In the expression of the fractional derivative, if terminals are reversed, that it's like a simple integral, add a minus sign, or there is a difference, or something to take into consideration.

  • Manual RNA extraction protocol just for PLANT material.

    Does any one used an excellent and fast manual protocol to extract and get purified RNA from plant material such as pulses leaf? 

    I will be appropriate if you share it with me. Many thanks.

    Chandra Shekhar Misra · Technical University of Lisbon

    i ma using normal manual method using BME and Chloroform isoamylalcohol and have not thought of using TriZOl. I am getting high Conc but the purity is not good as seen in the ratios. So if u have some modification in the protocol, then pls share.

    Problem lies for us when we use Eppendorf with 100mg starting material, we get low conc. but good ration but when the starting material we take 1g in falcon, the conc.  increases significantly but poor ratios. PRobbably our sample has lot of phenols and anthocyanins which we are not able to remove in the large falcon which casues interference. pellet is always colored which should not be the case.

  • What is the best approach to build a multi-center database for neuropsychological & medical data?
    I'm interested in building up a multicenter database (3 centers), incorporating personal, neuropsychological, and medical data. What is the best (and most convenient) method to start building up such a database. What are your experiences with MS Office Applications such as ACCESS (and EXCEL). Problematic with this approach seems to me personally that you have 3 different databases (in my case) that have to be merged to one single big database. What would be a good alternative? Does anyone has ever used a web-based system such as LORIS (http://www.frontiersin.org/Journal/10.3389/fninf.2011.00037/full). What about data security with web-based systems? Any ideas or other suggestions?
    Tünde Csenge Sipka · University of Szeged

    Red Cap might be a good option for you: http://www.project-redcap.org/
    It is free for certain institutions, highly logical and useful for multi center data bases.

  • Christoph Grützner added an answer in Geology:
    Any ideas for teaching geology to a blind student?

    I would appreciate any suggestions for effective methods for teaching geology to a blind student. 

    Christoph Grützner · University of Cambridge

    You might want to contact Prof. Domingos Rodrigues from the University of Madeira: https://www.researchgate.net/profile/Domingos_Rodrigues3?_sg=fzTcScJg2HU3R8LWFhjiu%2B2Ix213tNqu480dG%2Ff27Npi%2F51lMevPghUuBSW90hlI_mD7r3FM3D%2BvDAEtRAPclHOCtuN9jO166ST7clwFblzrAd6Y1jK%2BNw19eba01d8FM_OZmHHBpTP9CQ3vcap69Wz502HL6jk3W84%2BcoB1hrGTOd1d6oHApkhu8QubBqp2mC

    He organised geological excursions for blind lay people.

  • Vinita Jindal asked a question in VANET:
    Can anyone help me in selecting suitable clustering algorithm in VANETs

    I am searching a suitable algorithm for VANETs that is using clustering algorithm in adaptive manner. Please suggest me the best  in the case. Thanks in advance.

  • K. Kassner added an answer in Space:
    Is there more than one theory of gravity that can demonstrate compatibility with the Einstein equivalence principle?

    I am looking for theories that give different observations, i.e. that are measurably different.

    • Observations must match Minkowski space in free space.  This is a theoretical question.  Not looking for radical theories that would violate Minkowski space.
    • Each theory must be able to demonstrate that observations in an accelerated elevator in free space are the same as in an elevator sitting on a planetary surface.
    • Please show how multiple elevators over an extent of space are integrated to give the different observations of each theory, i.e. how the same local observations integrate differently.
    K. Kassner · Otto-von-Guericke-Universität Magdeburg


    "It's interesting because the Ricci scalar of this metric when made isotropic becomes R = 0, but Ruv ≠ 0"

    How can the Ricci scalar of a metric depend on whether the latter is made isotropic or not? The Ricci scalar is coordinate independent, so it should be the same whatever coordinate transformation you apply to your metric.

  • sai giridhar Sairam added an answer in Antigen:
    Does anyone have any information on concentration ratios for monoclonal antibody against antigen for antigen capture?

    Is there a standard ratio of concentration of monoclonal antibodies against a particular antigen for an antigen capture assay? To put it plainly how much monoclonal antibody is needed to bind to "x" concentration of antigen.

    sai giridhar Sairam · Sri Sathya Sai Institute of Higher Learning

    Hi Frank

    I am working on a competitive ELISA technique that involves incubation of antigen (blood serum sample) and antibody (monoclonal) in a test tube. The contents of which are then transfered into the ELISA plates coated with pure antigen.

  • Jing Yang Tee added an answer in Fixed Cell:
    Best way to wash cells for immunostaining to avoid crumpling & wrinkling of the cellular structure

    The plates I've been using are polystyrene, tissue culture treated, round well 96-well plates.  I've noticed that only ~25% of the fixed cells retain the monolayer spread whereas the rest have wrinkled but remain attached after the whole immunostaining protocol (i.e. fix, perm, block, washes and antibody dilutions).  This phenomenon is most noticeable around the edges of the well; the cells that were unaffected were all in the center of the well.

    For the washing steps, I use a vacuum-assisted tubing connected to a P200 pipette tip at the lowest possible suction that allows me to remove all the solution in the well.  I've always positioned the tip at the edges without touching the bottom. 

    Would you suggest a different method to remove the solution when washing?

    Jing Yang Tee · Griffith University

    @Konstantinos: I use freshly prepared 4% PFA pH adjusted to pH7.4 in DPBS. Incubation time was 10 min RT. 

    My first impression is that it has to do with the washing steps because the cells in the middle of the well are fine but as I move the well further out towards the edges, I start to see alot of wrinkled cells.   

  • Mario Lepage added an answer in Coastal Ecology:
    How do I analyze dissolved metals in estuarine waters?
    Estuarine waters
    Mario Lepage · National Research Institute of Science and Technology for Environment and Agriculture

    Hi Akshaya, I have colleagues that do dissolved metal measurement regularily in the Gironde estuary. You may be interested in one of their paper where they use ICP MS for this purpose.


    Dabrin, A., Schäfer, J., Blanc, G., Strady, E., Masson, M., Bossy, C., Castelle, S., Girardot, N. and Coynel, A., 2009. Improving estuarine net flux estimates for dissolved cadmium export at the annual timescale: Application to the Gironde Estuary. Estuarine, Coastal and Shelf Science 84, 429-439.

  • Muhammad Fahad Ehsan asked a question in CO2 Reduction:
    About CO2 Photoreduction. Can anyone help?

    The major product from my photocatalyst is methane. But the valence band edge of the photocatalyst is less positive than the oxidation potential of water. It means that the holes produced in the valence band of photocatalyst won't oxidize water to produce H+ which would then facilitate the CO2 reduction to CH4. Can anyone please help me how to justify this or if you can provide with some suitable literature addressing such case. I would be grateful!

  • Or Gertman asked a question in Immunofluorescence:
    Can't see my protein in Immunofluorescence assay


    I am trying to see flag tag protein (clonned in pcDNA plasmid) in U2OS cell line using immunofluorescence assay. My control (pcDNA+GFP) show high transfection efficiency (>80%). however, in the microscope I see that only ~5% of the cells containing my flag protein (colored red). My primary antibody is m anti FLAG from SIGMA. my secondary antibody is alexa555 from abcam. 

    I see the protein in western blot using the FLAG antibody.