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  • Patrick N.B. Anongba added an answer in Elasticity:
    What is the most general available expression of a three-dimensional biharmonic function?

    Biharmonic functions f (∆∆f = 0; ∆: Laplace operator) are used as components of Galerkin vector, in the mathematical treatment of problems with stressed solids, at equilibrium. I have found personally expression of the form (... + a/(k.x) + a0 + a1(k.x) +a2 (k.x)2 +...) exp(i k.x), where k and x are three-component vectors, k.k=0, and ai are complex numbers. I am currently using this expression but I wonder whether there are other available more general forms.

    Patrick N.B. Anongba · University "Félix Houphouët-Boigny"

    Again, I am reading at the moment on 3D twistors and biharmonic equation but I have to understand first before saying anything else. Thanks for above comments

  • What is the best classification for Palmoplantar Keratoderma (PPK)?

    Palmoplantar keratoderma is also sometimes known as ‘keratosis palmaris et plantaris’. Constitutes a heterogeneous group of disorders characterized by thickening of the palms and the soles of individuals who are affected.

  • Saleka Tamkinat added an answer in English Language:
    Is there a Context Free Grammar (CFG) for Shallow Parsing (English)?

    I am looking for a Context Free Grammar (CFG) for shallow parsing english language text. I want to extract meaningful constituents from sentences e.g. noun phrases and verb phrases.

    something like the rules below but with better coverage 

    grammar = r"""

    NP: {<DT>? <JJ>* <NN>*} 
    P: {<IN>}
    V: {<VB.*>}
    PP: {<P> <NP>} 
    VP: {<V> <NP|PP|>*} 

    #Taken from Wang and Li 2010 (SJTULTLAB: Chunk based method for keyphrase extraction)

    Saleka Tamkinat · Stanley College of Engineering and Technology for Women

    I would suggest the stanford parser will help you extract noun phrases and verbs.

    Follow the link given

    Hope this helps

  • Muhammad BILAL added an answer in Climate Change:
    How to extract the Aerosol Optical Depth (AOD) from modis data ?
    I want to study the aerosol optical depth at 550nm using modis data. Is there any simple and clear methodology available to do that?
    Muhammad BILAL · The Hong Kong Polytechnic University

    Dear Manish, 

    Did you evaluate the MYD04_3K and MYD04_10K AOD observations using Expected Error [+/- (0.05 + 0.15AOD)]? Yes, MYD04_3K C6 almost has the same correlation as MYD06_10K C6 with the AERONET AOD measurements, but AOD observations from MYD04_3K are more overestimated than MYD04_10K AOD observations, as most of the observations fall above the upper envelope of EE. Overall, both MYD04_3K and MYD04_10K have only <20% AOD observations fall within the EE. According to my understanding, retrieval quality/accuracy is more important than correlation. 



  • Subhash C. Kundu added an answer in Creativity:
    Which comes first, Creation or Innovation?

    To be innovative you have to be creative.

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

    Creative people innovate. So, creativity comes first.

  • Yong Jia added an answer in Protein Crystallization:
    How many polymers could there be in the unit cell of a protein crystal?

    The protein could be a dimer, a tetramer, or a hexamer in the unit cell of the crystal, I wonder what is the known maximum number of polymers in the asymmetric unit, it doesn't have to be homodimer, homotetramer or homohexamer if you know what I mean. Thanks.

    Yong Jia · University of Adelaide

    I have checked the EMBL PDB highlights, it's really amazing that they could crystallize a virus. Maybe in this case we should consider the virus itself as a polymer, then the crystal becomes dimer? Anyway, interesting to know this! Thanks!

  • Costas Drossos added an answer in Oil and Gas:
    How easy is it to develop a positive communication between the oil and gas and the educational industries?

    After attending and presenting in the last GetEnergy Abu Dhabi meeting, how easy is it to develop a productive communication between the oil and gas and the educational industries. This help to identify the gap and find ways to close it considering the expectations of the oil and gas industry. 

    Costas Drossos · University of Patras

    Dear Dr. Khalid Salim Al-Jardani,

    Students should of course be prepared for jobs! But a real education system (NOT EDUCATION INDUSTRIES!!!) has as first objective to give a real scientific background to the students, irrespectively of future jobs. There might be the last year of undergraduate studies or a Master Degree, which give to the student more jobs oriented education. In any way, the oil and gas industries, if they want to help the education system, they may support economically without demanding a special program. The relationships between indusry and education is very delicate and should be treated carefully!  

  • Satish Kumar Sinha added an answer in Trees:
    Can we compare different anatomical properties in trees of different age groups in juvenile and mature wood?

    Can we compare different anatomical properties in trees of different age groups in juvenile and mature wood?

    Satish Kumar Sinha · Navsari Agricultural University

    Thank you sir

  • Does some one has an experience in treatment of Pachyonychia Congenita type 1 (PC-1, Jadassohn-Lewandowsky)?

    Pachyonychia Congenita type 1 (PC-1, Jadassohn-Lewandowsky) is an autosomal dominant ectodermal dysplasia characterized by nail dystrophy (Wedged nails), focal non-epidermolytic palmoplantar Keratoderma (FNEPPK) and oral lesions (Leukokeratosis). It has previously shown that mutations in keratin 16 (K16) cause fragility of specific epithelia resulting in phenotypes of PC-1 or FNEPPK alone.

  • Rohit Malhotra asked a question in XBRL:
    Are there better ways to relate "Value relevance" and Information reporting investments (Like XBRL) empirically?

    Value relevance as referred to market capitalization.

  • What is the best practical solution for coastal fisheries management?

    Community based management


    Ecosystem based management

    Explain briefly if you select an option

    Rajaguru Sri · National Institute of Ocean Technology

    Now everyone recommend the Integrated approach or Ecosystem based Management to solve any problem. 

  • How to mark NK cells in human intestine specifically?

    I want to mark NK cells by immunofluorescence in  human intestine, so I choose CD56 as a specific marker. But I found that CD56 is also called Neural Cell Adhesion Molecule(NCAM), which can be used to identify nerve fibers in the intestine. Now I wonder whether CD56 is a good choice. Please give me a good suggestion to mark NK cells in human intestine. Thank you so much!

    Hemavathi Dhandapani · Cancer Institute (WIA)

    Hi Jiao,

    I think you can use CD16 along with CD56 maker. If you are looking for activated NK cells you can also use NKG2D. 

  • What statistic should I use with two ordinal categorical lists of rankings?

    I have a number of rankings of countries based on various indices. For example, HDI, happiness, religiosity, etc.

    The basic idea is to check whether any of these are associated. For example, whether high HDI indicates high happiness levels, etc.

    Any suggestion is welcome. I am using SPSS primarily, and Deducer and RapidMiner sparingly.

    Chinchu C Mullanvathukkal · Periyar University

    Spearman's Rho and ordinal regression are what I had in mind. The doubts arose because the data here is not survey responses which I am used to. This is in the form of country names and indices, lists with 50 entries each.

  • Mingqing Wang asked a question in Digital Holography:
    How to reconstruct a clear image plane digital hologram?

    As far as I know, angular spectrum method is a good idea, but I can not get a clear reconstructed image. Could you give me some advice?

  • Prabin Pathak asked a question in ANSYS:
    How to merge coincident nodes in ansys ?

    I am modelling the rc beam with solid 65 for concrete and link 180 for reinforcement. I am using discrete method for reinforcement. While merging coincident nodes between concrete and reinforcement, i always get Zero nodes are merged. I tried changing tolerance value as well but nothing worked for me. 

  • Does the fundamental biology or physics preclude an atomic powered cell?

    Since cells can capture visible light for photosynthesis, the ability to capture and store high energy fast events seems feasible in principle. One can imagine ways to capture atomic energy for biology. Obviously there may be issues with genome stability, but there are very radiation resistance cells and others that thrive in high temperatures that would seem to challenge DNA and RNA as well as protein and membrane stability. How might be develop atomic powered cells?

    Ryan M B Hoffman · The Scripps Research Institute

    Nice question; the 'imagination' tag motivates me to answer. A simple mechanism would use some sort of scintillating material to convert a beta or gamma source into photons in the right energy range to excite a conventional photosystem. But I think the efficiency of the photosynthetic apparatus is too low to make this plausible...the radiation source would have to be strong enough that it would shred the genome. Are there any known microbes that harvest the light generated by a bioluminescent organism? I don't think life has an appropriately efficient photosynthetic apparatus to recruit for this purpose.

    So the next-most-obvious mechanism would recapitulate the key properties of a radioisotope thermoelectric generator. The question is then, how can an organism transduce a thermal gradient into a chemiosmotic gradient? This is an ambitious structure-activity relationship, bordering on a realized Maxwell's demon. The closest thing to it, that I know of, is thermogenin. This converts a proton gradient into heat. But the heat is not, to my knowledge, directed preferentially into one direction, meaning that the "reverse reaction" is also implausible. I don't think we can generate a proton gradient by heating one compartment that is gated by thermogenin.

    Since a respiratory/photosynthetic electron transport chain (ETC) is basically a system for an orderly cascade of redox reactions, probably the most plausible mechanism would generate radicals through ionization events, then shuttle the radicals to the ETC. So, can we reduce a quinone by incubating it with a radioisotope? I don't know off-hand how many aqueous radicals are produced by a hydrated chunk of plutonium, but a cursory literature search turned up a plausible mechanism (hydrogen peroxide production by hydrated uranium dioxide, linked below). Wikipedia tells me that quinones are actually industrially important for the production of hydrogen peroxide, as in:

    dihydroanthraquinone + O2 → anthraquinone + H2O2

    So, in broad strokes, it seems possible to a) produce hydrogen peroxide via a radiological mechanism, and b) harvest the electrons from hydrogen peroxide into a quinone, then c) using the quinone to feed the ETC and drive oxidative phosphorylation. I have to conclude, no, I can't see why an atomic powered cell is impossible.

  • Do phytoplankton community bioaccumulate heavy metals from the ambient aquatic media?

    Bioaccumulation of heavy metals

    Rajaguru Sri · National Institute of Ocean Technology

    Good topic. Heavy metal and  pollution is common in aquatic bodies. I like to write about marine systems or ocean. When it is discharged in the coastal sea, most of the pollutants dispersed due to large volume of water. But the heavy metal or any other toxic material keep on accumulate in sediment, so the accumulation may be more in the soil. Further we can not get growth of phytoplankton in the polluted waters other than organic pollution. Therefore the accumulation in phytoplankton possibility is very rare. But in closed aquatic system like ponds or lakes you can expect the positive results. Thank you for the best topic selected in Research Gate. 

  • Costas Drossos added an answer in Geometrics:
    Is time in geometrical form ? If yes, how to define the geometric shape? If not, then how is it?

    In the circuit model system, After the rise of the time axis in system of equations and operation we found that the time can be central axis and motion system and can form geometric.

    Costas Drossos · University of Patras

    What is "geometrical form"? Can we say that "geometrical form" is just a structure in algebraic terms? Let us take a circle C in the monitor of a computer. Actually I was to depict a sphere. So let us take functions f:T---->C. these functions actually are "variable elements" of C, and T represents "time". If f is a great circle, and continuo to draw many such great circles, then a sphere is revealed. These variable elements, as relations of T and C define a structure. In general in Category Theory, any arrow

    f:T--->A, can be regarded as "variable element", where T is considered as time domain. As you see we can give time a more general meaning than the usual one. I hope that i demonstrated that time is present in  geometrical forms! 

  • Zdenka Kroupova added an answer in Tax:
    How can I measure state tax efforts using the Stochastic Frontier Approach?

    Is there any method to measure shadow economy in order to use it as an independent variable to measure tax efforts of the state? How can I use the Stochastic Frontier Approach to estimate tax effort?

    Zdenka Kroupova · Czech University of Life Sciences Prague

    These publications can help you but I suppose that you know them:



  • What are free tools to convert a .wiff file into .mzXML file in an MS experiment?

    There exist tools like ProteinProhet and mzWiff (should have Analyst software installed) that are not freely available.

    Skyline is free, but doesn't seem to have a method of performing the conversion only with wiff files.

    Are there any other freely available tools?


  • Yuan-Yeu Yau added an answer in Petunia:
    How can two copies of a gene turn petunias white, since two copies do not make complementary mRNA?

    Jorgensen in 1986 working with petunias stumbled across RNAi. He inserted transgenic copies of chalcone synthase, a limiting enzyme in the synthesis of the flower's purple pigment, but instead of getting a very purple flower he got white flowers. Since it takes dsRNA to activate RNA machinery, how it was activated since two copies of the gene are not complementary, or are they actually?


    Yuan-Yeu Yau · Northeastern State University

    Several processes can lead to production of double-stranded RNA (dsRNA). Those processes include, for example, antisense transcription and transcription of inverted repeats (or transgenes) (see attached figure #1, 'a').

    When doing genetic transformation, two copies of transgenes can land inside a single locus with an inverted fashion ("inverted repeats"). When transcription across these two inverted transgenes occurs, a double-stranded hairpin RNA can form (Figure #2) and triggers degradation of homologous mRNA, resulting in transgene silencing.

  • Can anyone tell me about the residual stress role in shifting the diffraction peak position in XRD?

    can anyone tell me about residual stress role in shift the diffraction

    peak position in XRD?

    Tarik Ömer Oğurtani · Middle East Technical University

    XRD  Studies of Stacking Fault Segregation in Alpha Brass

  • Manjappa D Hosamane added an answer in Labor Market:
    Can someone suggest some articles regarding the relationship between labor market demand and fresh graduates employment?

    my research aim is to identify the affect of fresh graduates on labor demand and supply, whether this is supply is surplus or deficit according to market needs.

    Manjappa D Hosamane · University of Mysore

    Labour market has no direct relation with graduates. Graduates are skill labour only suitable for administrative jobs. hence you have to think alternative method.

  • What do you see as big accomplishments for synthetic biology?

    Synthetic biology offers interesting basic science and exciting potential value. What are examples of successes so far that show its potential?

    Sisubalan Natarajan · Jamal Mohamed College

    In this decade we can see the development and production of industrial products based on "Nano Technology". I agree that, this is one of the recent development successfully achieved by researchers in both ways as Synthetically and Biologically. Now these experts focused themselves to drug development using nano particles. The nano based drug activities are proved by many researchers against cancer cells too. I can see this is massive accomplishment  for synthetic biology and Its my own concern.

  • Is it possible to obtain different statistical significance results for independent variables for one way anova and univariate analysis ?

    The tests use the same sample population , same independent variables but statistical significance results are different i.e. statistical significant for each independent variable when tested using one way anova and not statistically significant when using univariate analysis for the same independent variables (tests of between subject effects table)

    Paul R. Yarnold · Optimal Data Analysis LLC

    Yep. One-way ANOVA is a univariate analysis (?) involving a single independent variable (not multiple independent variables), so the question is confusing.

  • Ashok Pabbathi added an answer in TCSPC:
    If a molecule gives two emission bands of equal intensity, then which emission band should be considered for calculating average life time?

    Molecules having charge transfer character sometimes give two emission bands (one from LE state and other from CT state). TCSPC measurements at these two bands give different average life time. Then TCSPC measurement of which band should be considered as average life time of the molecule.

    Ashok Pabbathi · University of Hyderabad

    In this case you have two different species i.e. LE state and TICT state.You cannot considered  both lifetimes to estimate the average lifetime of a molecule .We nevr do that..

    You should always monitor the emission of LE state to get its average lifetime and monitor the TICT emission to get its average lifetime.

  • Sovetgul Asekova asked a question in Reference Values:
    How to calculate standard error of laboratory (SEL)?

    Large samples (more than 300) to calculate standard error of reference values simple a guide or a plain explanation


  • John Tainer added an answer in Biochemistry:
    What are the best detergents to use for membrane dissociation and membrane protein complex purification that are likely to retain activity?
    We have had problems disrupting microbial membranes and separating the membrane proteins for purifications and then also preserving activities of large membrane protein complexes. With more detergents and information are there good detergents to try for these steps and can the same detergent be used to disrupt membranes and purifying complexes or is it better to switch detergents?
    John Tainer · The Scripps Research Institute

    So is there a possible top 5 or 10 list of detergents that would be most appropriate for many membrane proteins or does each protein require more comprehensive separate testing? 

  • David Budden added an answer in Pathology:
    Which is the most appropriate supervised neural network architecture between multi-layer perceptron and radial basis function to classify gait data?

    Dealing with kinetics, kinematics and their principal component values, which is the most appropriate neural network architecture between multi-layer perceptron and radial basis function in order to discriminate between pathological and non pathological gait data?

    David Budden · University of Melbourne

    This depends on the nature of the data (particularly the dimensionality and number of observations). RBF isn't a NN architecture (to the best of my knowledge!) but a commonly-adopted kernel function for support vector machines (SVMs). If you're relatively new to machine learning, SVMs typically give very good results with minimal effort, whereas NNs require a lot of decision making re: #neurons, #layers, connectivity, and then the parameterisation of your weight-optimising algorithm.