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  • How can researchers be defined as 'skilled' when they focus research on the 'unpredictable unknown'?

    It's all in the question

    Michael Patriksson · Chalmers University of Technology

    Well, to begin with one has to assume that whoever digs her teeth into research has a strong educational background. Hence, she is skilled in the basic theory and practice of the field of study at hand. (Otherwise, you would not call her a researcher, but an amateur, right?) Second, you are well aware that a lot research is NOT about searching the unknown. In fact, I bet that 3/4 or more of the research that we read is of the incremental type - small additions are made to already existing theories, practices, and methodologies. I do not refer to that most common research as "working in an unpredictable unknown" area, would you? :-)

  • Aniruddh Kashyap added an answer in SNP Genotyping:
    What sample size is ideal in cancer-related SNP genotyping studies? How is the significance of the study determined?

    How do you determine if the study involving very few (e.g. 20-30) samples might affect the whole population?

  • Abhishek Basak added an answer in Solvents:
    What is the solubility of ZrF4 in organic solvents (like ethanol, DMF, THF, etc)?

    I am looking at determining the water content in ZrF4 salts (both hydrated and anhydrous) using Karl Fischer titration. I was looking at first dissolving the salt in an organic fluid and doing a coulumetric titration. For this I am looking at ethanol, DMF and THF as solvents. Does anybody have an idea of the solubility of ZrF4 in these solvents (i mean in terms of mg/L or such units)?

    Abhishek Basak · Bhabha Atomic Research Centre

    Well I am aware of DMF, but I read somewhere that only hydrated ZrF4 gets dissolved in DMF, not anhydrous ZrF4. Hence, I am looking at other options for zeroing in on a general method.

  • How can I compare community functional diversity across space and time?

    I am working with a dataset of six communities that were sampled at two time points. I am looking for a simple way to see whether functional diversity of each community has changed from time point A to time point B.

    My functional data is count data [number of species per community with a given functional trait]. As such, my dataset seems too small for most ordination approaches. Overall, I am investigating multiple traits within three different functional categories [growth form, habitat preference, and symbiont status]. At the moment, I am treating each functional category as a separate dataset.

    Thank you!

  • Would anyone like to get a silicon photonics chip made?

    It is very valuable to validate your simulations using real fabricated devices.  In particular, many people ignore manufacturing variability in their simulations.

    We are including electron beam lithography fabrication in our online course: http://bit.ly/UBCxPhot

  • Jorden Manasse added an answer in Camels:
    Does anyone have any ideas or diagnosis for this lesion of female camel genital tract in the picture below?

    The abnormality was on the bifurcation of the uterine horns in female dromedary camel.

    Genital tract of female camel  aged about 16 years, collected from slaughterhouse.

    Jorden Manasse · University of Wisconsin–Madison

    Send for histopath. Consider Oesophagostomum - however, that is usually in the serosa of sheep intestine....

  • What is the climate change induced increase (per decade) in surface water temperatures and salinity in the worlds oceans and seas?

    Climate change induced an increase in the surface water temperatures and salinity in various oceans and seas in the world. I need the amounts of their increase per decade in past several years. Please attach the article as references with your valuable reply.

    Shankhadeep Chakraborty · Techno India

    Dear Kenneth, thanks a lot for the article. I was in search for this type of article and asking you repeatedly for contribution. I have got my answer. Dear Demetris, thank you for your contribution.

  • Cleverton Pirich added an answer in Plant Extracts:
    How do I incorporate plant extract into a polymer film?

    I have synthesized bio-polymer  film. In order to improve its properties, i want to incorporate the plant extract into the films. Is there any proper method to incorporate extract into films?

    Will the concentration of extract effect the physical properties of films/membranes?

    Keywords: Chitosan, Gelatin, Plant extract, physical properties, thermal properties

    Cleverton Pirich · Universidade Federal do Paraná

    You will have to test the adsorption process of your synthesided biopolymer onto film by do an isotherm. You will need to test diferents concentrations and media condictions (pH, temperature, salts, time of adsorption...). After you achieved the isotherm profile, you will need to evaluate what kind of behavior it have for you fit. For example, langmuir, freundlich...

    What kind of films are you intend to adsorb?

  • Michael Primrose asked a question in Polaron:
    What are the features in a Raman spectrum that indicate polarons?

    I have some Raman spectra that have some unexplained broad features. Polaron hopping as a conduction mechanism has been shown in this material, but I am not familiar with how polarons would be present in a Raman spectrum. 

  • Gecele Matos Paggi asked a question in DNA Extraction:
    Does anybody have a DNA extraction protocol for animal tissue? For fresh or conserved (alcohol) tissue?

    I would like to use it for snakes... muscles, skin, scales or liver... thank you!

  • Abbas Rahdar asked a question in Nanotechnology:
    Please introduce me a nanotechnology research center at a university in Germany to spend a sabbatical ?

    please introduce me a nanotechnology research center at a university in Germany to spend a sabbatical ?

  • Amir Abbas Talebi asked a question in Typing:
    There are several types of conductors for overhead lines and the use of which is greater?

    There are several types of conductors for overhead lines and the use of which is greater?

  • The voltage transmission lines are divided into several categories?

    The voltage transmission lines are divided into several categories?

  • Himanshu Kumar asked a question in Bacteria:
    A bacteria showing optimum growth at pH 6 then can they fall in acidotolerant group of bacteria?

    A bacteria showing optimum growth at pH 6 but can resist up to pH 5 so can we say them acidotolerant/ moderate acidophilic/acidoresistant. What would be the appropriate term for this bacteria. Your comments are valuable .........

  • Mj Woodward-Greene added an answer in Beef Cattle:
    Exists any guidelines for water needs of livestock in according to temperature and other important factors?

    For estimating future water needs in agriculture in terms of climate change I need information about water needs of livestock (beef cattle, dairy cattle, pigs, horses, sheep, goats poultry, etc.) in according to temperature and other important factors (kind of stabling, diet composition etc.).

    Mj Woodward-Greene · United States Department of Agriculture and George Mason University

    There are many references in older literature. Here is a link to information (online) on factors varying the water requirements for Beef cattle, out of the University of Nebraska:

  • Zehao Yang added an answer in PID Control:
    In MATLAB, can nonlinear pid be included into Simulink. If so, can anyone help me to do so?

    I am planned to use nonlinear pid controller instead of linear, could anyone help me in this regard.

    Zehao Yang · Rensselaer Polytechnic Institute

    If you are doing gain-scheduling PID you can certainly do that using the normal PID block plus the gain-scheduling variables. An easy way for gain-scheduling is to use the local controller network proposed by Hunt et al. 

  • Tanima Mallik asked a question in Leukemia:
    A gene mutation causes defect in DNA methylation and caused leukemia.But cloning of this gene in normal bone marrow cells cause no leukemia.How?

    A particular leukemia is associated with a defect in DNA methylation system caused by a particular gene mutation.The cloning and transduction of this gene in normal bone marrow cells cause alteration in DNA methylation but does not produce leukemia.Does it mean that DNA methylation and leukemia are not related?

    What could be the possible explanation to describe that the particular mutation was required but not sufficient to the development of leukemia?

  • Are there any practical solutions available for searching on encrypted data using regular expression?

    I would like to perform regular expression search on encrypted document. Looking for some practical solutions available for this purpose?

    Qasim Mohammed Hussein · University of Tikrit

    I know what means regular expression because I taught this subject in computation theory and compiler techniques.

    In fact, when an encryption system is designed, it must taking into consideration the difficulty to find a way to find equivalent encryption key that may be used by the third party. Also, the key generators must have a high complexity. so, i think for a good cryptosystem, it is impossible to find regular expression. you may be find regular expression to weak and simple systems.

    Best wishes

    Dr. Qasim

  • Sajjad Nazidizaji added an answer in TRIZ:
    How can I find papers about TRIZ plus: benchmarking and feature transfer?

    I am learning TRIZ plus,including bnechmarking and feature transfer,but I can hardly find such papers, so I wonder who can help me to find some? 

    Sajjad Nazidizaji · Technical University of Lisbon

    Dear Guang Jiang

    I dont know what is exactly bench marking and feature transfer

    Have you seen the TRIZ journal or papers of ETRIA conference in sciencedirect ?

  • Which one is right to describe Hafele-Keating experiment (twin paradox)? SRT, GR, absolute referential, modified clock frequencies?

    Is there a distinction of Sagnac effect between SRT and GR or absolute referential is enough? Are the clocks runing at same frequencies?

    Dear Azzam,

    A different rates of time does not "affect" on the simultaneity of moments, They "influence" on the length of the interval, but they also "influences" and on the tempo of clock to the same extent.  The same applies to the rulers. This gives us the opportunity to talk about the same description of the same processes in the linear case in IRF. But this does not mean that the same can be done in the nonlinear case, or in a non-inertial frame of reference.
    There are people who believe that they are doing the right thing, supporting corporate opinion against the results of some experiments, convincing themselves and others that the theory of relativity works everywhere since it confirmed by numerous experiments with some accuracy. They don't want to suppose that may be a theory that gives the best accuracy. I think we should demonstrate these people not on their mistakes but on our advantage.

    Уважаемый Azzam,

    Разный темп времени не влияет на одновременность моментов, Он «влияет» на длительность процессов, но он «влияет» и на темп хода часов в той же степени, то же самое касается линеек. Это дает возможность говорить об одинаковом описании процессов в линейном случае в ИСО. Но из этого никак не следует, что то же самое можно сделать в нелинейном случае или в неинерциальной системе отсчета.

    Есть люди, которые считают, что они поступают правильно, поддерживая корпоративное мнение против результатов некоторых экспериментов, убеждая себя и других, что теория относительности работает всюду, поскольку подтверждена множеством экспериментов с некоторой точностью. Они не желают думать о том, что может быть теория, которая дает лучшую точность. Я считаю, что нам следует показывать этим людям не их ошибки, а наше преимущество.

  • Zia ur Rehman added an answer in Cyclodextrin:
    How do I run the molecular dynamics of beta-cyclodextrin and p-nitrophenol on abalone?

    I am working on abalone software and I tried running the MD of cyclodextrin and nitrophenol.As soon as I start the MD,nitrophenol gets deformed.How to solve this problem?

    Zia ur Rehman · Stockholm University

    It will also be important that which basis sets you used while optimizing as nitrophenol contains lone pairs and I think you might have to use diffused basis sets.

  • How does one interpret the output from a 'PGLS-Relationships' analysis in Compare 4.6b?

    The output includes results for PGLS at a given alpha value, Felsenstein's independent contrasts and TIPS (where phylogeny is not accounted for). In my case, mean PGLS carries high alpha values and both FIC and TIPS have alpha values of 0. Should I simply focus on the PGLS and treat the others as hypothetical scenarios? Should I use the PGLS alpha as my guide for acceptance/rejection of the other two? Or alternatively, should trust be given to the set with the highest likelihood? Also am I correct in stating that R^2 measures the extent to which phylogeny accounts for the observed correlation?

  • Rajat Pradhan added an answer in Photons:
    Can a photon exhibit multiple frequencies?

    Can a photon be a superposition of multiple frequency states? Kind of similar to how an electron can be a superposition of multiple spin states.

    Rajat Pradhan · Utkal University

    yes, practically speaking all photons are like that. The wave packet description tells us that there will be a frequency range for it, provided the wave packet description is applicable to them.

    We can measure anything with a spread only and not with an exact value.

  • What are the Variance of estimator with capture-recapture?

    I have doubt about the variance of :

    N=[(n1+1)(n2+1)/(n11+1)]-1    is the Chapman estimator


    N=n+(n1^2/4n11)   is the Chao estimator developed by Brittain and Bohning

    What are the  formula of variance of estimators? And If I use the formula's variance, Var(N))=[(n1+1)(n2+1)n10n01]/[(n11+1)^2(n11+2)], my output of variance by both estimators can comparative and what my affect of the 95%CI of N?

    Thank you so much

    Ratchadabhorn Ungcharoen · Kasetsart University

    Thank you so much :) for Dan and Jabi

    I have doubt about variance of both estimator. Sometimes, I found in some  paper use the variance as same as for both estimator.

    Jabi Zabala-Albizua and I can not download from http://chao.stat.nthu.edu.tw/paper/2001_JSPI_92_P213.pdf   

    Thank you so much

    Best, Ratcha

  • Himanshu Kumar asked a question in MIC:
    Suggest me the protocol for determination of MIC (minimum inhibitory concentration) for hexavalent chromium?

    Being a color compound, the determination of MIC value for hexavalent chromium is difficult therefore add your views or answer...

  • Sergei Tarasov added an answer in Paraffin:
    How can I grind paraffin pellets to microsize?

    I have paraffin pellets (size around 2 mm) and I need to grind them to microsize (10-100 micrometers). I search for a easy and efficient way to grind them.

    Sergei Tarasov · Russian Academy of Sciences

    Why not using cryomillling?

  • Micro laser welding, is there a crack in the picture attached?

    Hi guys,

    My name is Rogelio H. Aguirre, a grad student at the University of Waterloo working on MEMS sensors. Currently, I am working with micro laser welding suppliers to fabricate the packaging of a pressure and a temperature sensor. I have some experience with welding, but not in micro laser one. I am welding a TO Header Substrate made of KOVAR with a Steel case. The device should resist a high pressure of 600 psi; however, I have some leak issues on the assembly at 300 psi approx. I am not sure if the leak is on the welding line, for me, looks like is in the center of the device. To check this, I check the sample using a microscope with an MPlan APO 20 lens, here is where I need your expertise guys. I am attaching a file with 4 pictures, two are under the microscope, do the images attached shows a fracture or crack on the welding line? According to my knowledge is not a crack, but I want to check with you guys.

    Thanks a lot


    Rogelio Hernandez Aguirre · University of Waterloo

    Thanks for your reply guys,

    I used a Vertical Mount type microscope with an objective  M Plan Apo (Apochromat) Super Long 20X with a VL2X lens. The photo was taken with a Microscope Digital Camera MDC320. I also played with the focal plane, and there is not a big difference when I move the focal plane, there is almost the same image.


  • How can I separate a cleavaged GST-protein from glutathion agarose after on-column thrombin digestion?


    I`m trying to purify a GST-fused protein by overexpression in bacteria and purification with glutathion agarose column, and everything is ok until I want to remove the GST tag from my protein using thrombin, the thing is that after digestion and elution (in PBS), I get nothing in the elute, but I do clearly see (by SDS-PAGE) the digested protein "sticked" to the column.

    Can anyone know why or how could I elute the digested protein?

    Thank you,

    Gabriela Hernandez-Puga · Universidad Nacional Autónoma de México

    yes my protein is soluble..... so I´ll have to work with incubation time and protease concentration. 

    Thank you!