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  • Kenneth M Towe added an answer in Earth Sciences:
    What is the weakest thing about uncertainty theories and algorithms in geology?

    I believe that uncertainty assessment approaches are not well-developed in earth-sciences. Do you consider it as a deficiency?? If yes, do you have any solution for any case? We can discuss and work on it together. :-)

  • Tahoora Sheikhy Narany asked a question in Kriging:
    What is the main difference between Indicator kriging and Disjunctive Kriging?

    and which one is suggested for creating probability map of water contaminant?

  • Joel Cruz Delos Angeles added an answer in MATLAB:
    Hello! can anyone give me the codes for enter spoken words into Matlab?

    In need it for my computing project

    Joel Cruz Delos Angeles

    Hi.  My answer may not be complete.  I don't fully know the answer if you want to recognize words for speech recognition.  But if just want to feed Matlab with a recorded voice, then you can record the the audio to a wav file.  Then matlab has a wavread() function which reads the audio file and stores in into a one-dimensional array.  The link might also help  - which is a work of my colleague and uses Mel frequency ceptrum coefficients to recognize spoken words.

  • Stam Nicolis 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?

    Stam Nicolis

    Not regarding special or general relativity, but this is totally irrelevant to the discussion. The mathematics is what matters. Who did something is of interest for history-the something is what is interesting and much has been learned since Einstein's work, so there's no point in pretending that it isn't known. 

  • Karizza Luz Aguinaldo Imperial added an answer in Parental Involvement:
    Has anyone experienced using Perception of Parents Scale in their studies?

    Where did you relate the variables?

    Karizza Luz Aguinaldo Imperial

    Oh, thank you Sandra. :) Specifically, I would like to use the Perception of Parents Scale, which is created by Deci and Ryan.

  • Talaat Elkady asked a question in Peroxides:
    What is the relationship between acid value and peroxide value in oils ?

    oils peroxide value

    acid value

  • Enver fehim koçpınar added an answer in Saw:
    Western blotting

    although I saw spesific binding before. now I don't see any spesific bind. everything that I use is same but I didn't see at the latest a few assays. What could be the problem? Is it perishable homogenates? my homogenates have been waiting for about 6 months and without proteases and B-mercaptoethanol

    Western blot non-specific bands?

    Enver fehim koçpınar

    although I saw spesific binding before. now I don't see any spesific bind. everything that I use is same but I didn't see at the latest a few assays. What could be the problem? Is it perishable homogenates? my homogenates have been waiting for about 6 months and without proteases and B-mercaptoethanol

    Western blot non-specific bands?

    I have basic one question? how I save primary and secondary antibodies which I used it before.

  • Marcelo Guimarães Silva added an answer in Gait Analysis:
    What's the best way for warehousing gait analysis data?

    3D gait analysis laboratory generates a huge amount for the subject.For many subjects such normals and abnormals gait, what's the best way to store these data so that we can do different statistical processing on them later. should we save the gait cycle data as rows or columns Are there any software for gait data warehousing?

    Marcelo Guimarães Silva


    I would recommend that those data can read by Matlab, a developpment of a specific routine for gait phase analysis and determination of the variables (e.g. step time, stance time). To verify the statistics, I recommend the SPSS for a thorough statistical examination between groups/participants, you will can une ANOVA with repeated measures.

    Hope it's useful!


  • Kok Sim Chan asked a question in Genomic DNA:
    How to remove cuticle of Caenorhabditis elegans?

    I am interested in obtaining the genomic DNA of C.elegans, but the outer cuticle layer reduce my total genomic DNA concentration, any suggestion on this?

  • Buket Seçkin added an answer in Acrylamide:
    How can we cope with upper gel problem in Western blot?

    When we prepare the top acrylamide/bisacrylamide gel, we put the cassettes on it and wait for the polymerization. After 1 and half hour we take away the cassettes and see no wells on the top gel. Some wells are good but some others are in different shapes and sizes. We can not pour the samples in them. We changed the cassette type but nothing changed. In our top gel formulation we put 29.2:0.8(acryl-bys). Can anyone help us out of this? Thank you.

    Buket Seçkin

    Hello, I think the link below can help you about your solution's percantages, especially the table at the bottom of the page. By the way, maybe your gel did not dry completely so that's why the wells did not shape properly, so if it is the problem I think you should decrease TEMED percentage in your gel solution.

    Hope these help, best regards,


  • Rafael Matos-Wasem added an answer in Industrial Heritage:
    Which is the principal industrial heritage in the world? And in your country?

    (Qual é o principal patrimônio industrial no mundo? E em seu país?)
    (Cual es el principal patrimonio industrial en el mundo? Y en su país?)

    "Industrial heritage consists of the remains of industrial culture which are of historical, technological, social, architectural or scientific value. These remains consist of buildings and machinery, workshops, mills and factories, mines and sites for processing and refining, warehouses and stores, places where energy is generated, transmitted and used, transport and all its infrastructure, as well as places used for social activities related to industry such as housing, religious worship or education". (Nizhny Tagil Charter, TICCIH, 2003)

    Rafael Matos-Wasem

    Dear Ronaldo,

    Although La Chaux-de-Fonds' watchmaking industry is still active and quite successful, it's town planning and some abandoned workshops could be considered as being specifically industrial heritage. Here and there in Switzerland you find abandoned factories or for example also railway (depots, vehicles, etc.) or hydroelecztical infrastructures (hydroelectric power plants). Some buildings formerly industrial have been transformed in museums, flats and lofts, shopping centres, etc.

    It's quite difficult to identify a really outstanding and specific feature in this area in Switzerland.

    Kind regards.


  • Thierry Wambo asked a question in Carbonic Anhydrase I:
    Which of PH-sifted assay or esterase assay is the most accurate?

    I am not very familiar with techniques used in experiments when it comes to find Ki of a ligand. For a protein such as carbonic anhydrase, I realized (from litterature review) that the reported Ki for the same molecule will generally vary if the PH-sifted assay is used instead of the esterase assay. Apparently PH-sifted assay usually gives lower values than the other technique. Which of these techniques should be most trusted or is more accurate?

    Thank you!

  • Saara Hiltunen asked a question in Human Resource Development:
    Has anyone here been involved with research in connection to crosscultural trust development in partnerships?

    I am interested to find colleagues who have researched crosscultural trust development along with partner development.  I am working in the area of human resource development for health services. 

  • Hala Hazzaa added an answer in Drug Targeting:
    Is it possible for a protein not to be detected at p-blast but show positive for its presence at Immunocytochemistry staining?
    Shows expected drug response with receptor antagonists though-
    Hala Hazzaa


  • Aaysha Cader asked a question in PCI:
    Is there any role of prasugrel and ticagrelor as part of dual antiplatelet therapy after stenting in STABLE coronary artery disease?

    Ticagrelor and prasugrel have been advised in STEMI and NSTE-ACS after PCi. what about SCAD??

  • Angelina Nduku Kioko added an answer in Applied Linguistics:
    How should I determine the underlying forms of these noun stems?

    Hello everyone, I have some data from Ganda (Luganda), which is a language in the Bantu language family. I can not determine which are the underlying forms for their noun stems. I give the data as in the follows. 

    singular                     plural                    My assumption

    lulagala                     ndagala                    dagala

    lwatika                       ɲjatika                       jatika

    lweyo                         ɲjeyo                        jeyo

    luuyi                          ɲjuyi                          juyi

    lugambo                    ŋŋambo                    ŋambo

    lulimi                          nnimi                         nimi

    luyombo                    ɲɲombo                    ɲombo

    lwendo                       ɲɲendo                    ɲendo

    lunaku                       nnaku                       naku

    luyola                        ɲjola                          jola

    lupapula                    mpapula                   papula

    This question has been bothering me for a very long time. If I assume the above stems, it would be easy to explain the plural alternations, it is to add the plural prefix n- to the stems, but it would be hard to explain how the singular forms are formed, the singular prefix is lu- or lw- (before vowels). Your ideas and suggestions are highly appreciated!

    Angelina Nduku Kioko

    There is much logic in what Mathew says.  It is just that it does not seem generalizable to all the data, even in this sample.  One possible motivation for the 'insertion/doubling of the nasal could be syllable structure constraints.  My response initially was based on the assumption that question required an accurate response, and you cannot obtain an accurate response on underlying forms in many Bantu languages without examining the whole paradigm.  When I have time, more time than I have currently, I will explore what possibilities one can get to with the limited data that had been provided.

  • Peter J Mponzi asked a question in Hydrocracking:
    Is it important to remove water and CO2 between HDO and HC process?

    I was wondering if it is very important to remove water and CO2 between Hydrodeoxygenation and Hydrocracking process. What will happened if water and CO2 is still in the HDO and liquid (oil) is transfer into the HC?

  • Hubert Beaumont asked a question in Metrics:
    Is that always correct to compare waterfall plots?

    I would like to asses the changes, and the magnitude of changes, between two dates for a given dataset. More precisely, I would like to compare the sensitivity of two different metrics to know which of these metrics is the most appropriate to detect changes. My question is: Is that correct to compare the performance of these two metrics using waterfall plots? In other words, is that correct to rely on waterfall plots to compare two different things (Kg versus cm)?
    Thanks for your comments.

  • Niranjan Kotla added an answer in Nanocapsules:
    Does anyone know a cationic polymer like Eudragit RS-100 for Nanocapsules, but biodegradable?

    I will start to work with nanocapsules and need to use a cationic polymer, like Eudragit-RS100. But, we will spray dry these nanocapsules to use in pulmonary route. As we know, Eudragit RS-100 is not a good candidate because it is not biodegradable and can be stored at the pulmonary branches. Anyone know a polymer like EUDRAGIT - RS100, but biodegradable? Thanks in advance.

    Niranjan Kotla

    Eudragits generally used for colon targeted drug delivery systems to retard the drug release in upper gastric tract. Upon pH rising to more than 6.8 (colon PH) this polymer dissolves. You can try PLL or PAH or Chitosan for poly-cationic layer/coating.

  • Lin Cheng asked a question in High Pressure:
    Do anyone know any cell model of glaucoma other than elevated hydrostatic pressure culturing?

    I searched online that there are several animal models of glaucoma. However, it seems that no cell glaucoma model is available. Some publications use elevated hydrostatic pressure cultured RGCs as a cell glaucomatic model. Due to no equipment to induce high pressure in incubator, I am wondering whether there are some other cell models of glaucoma other than high-pressure induction. Thanks for your time. 

  • Olivier Monfort added an answer in Hydrogen Production:
    What are the best materials for hydrogen production? How can these materials be prepared? What techniques can be used for materials characterization?

    Dear friends, I am trying to learn more about hydrogen production by water splitting.

    Thanks in advance, Pedro Villegas

    Olivier Monfort

    Hello, you have to precise your question... hydrogen production is very a large theme of materials science and electrochemistry.

    first, H2 production can be produce by various methods such as photocatalysis, photoelectrocatalysis, electrocatalysis, etc.

    then, several methods can be used for preparaing materials: chemical deposition such as sol gel process, hydrothermal methods, etc. or physical deposition such as pulsed laser deposition, magnetron sputtering, etc. and so on...

  • Filippo Salustri added an answer in Analogy:
    Is analogy the key to understand thinking?

    Hofstadter and Sander write in their book "Surfaces and Essences: Analogy as the Fuel and Fire of Thinking" that analogy is a key issue for cognition and perception. They put analogy into the center of all mental tools. I think analogy is a powerful tool but it is a tool beside others.

  • Noraziahtulhidayu Kamarudin added an answer in Feature Vectors:
    What factors affect accuracy in fusion on feature vector?


    I need to find on certain factors that may affecting the fusion of feature vector on speech signals? Like the usage of MFCC and LPCC or other algorithm such as MFCC and MLP as bottleneck feature.

    I have find out that the usage of MFCC and LPCC as input for feature vector and gives very good accuracy but when it fused together the results slightly downgraded although have tried with matric changes. Please advise.

    Thank you

    Noraziahtulhidayu Kamarudin

    Thank you Dr Amir and Mr Thamil for your answers:)

  • Xina Li asked a question in Innovation Network:
    How can I prove that innovation network exist and evaluate it?

    If I want to prove that innovation network is exist in Shenzhen High-tech Industry, how can I prove that? Is it possible to prove that without questionnaire survey? And how can I evaluate the strength of the network? Looking forward to your answer.

  • Marković G. Đoko added an answer in Physical Cosmology:
    What is casimir energy ,force or effect ? What is dark energy ? and what is the connection between the two ?

    Tthis is a fundamental question in physics and cosmology

    Marković G. Đoko

    Here's an interesting side dish instead of my answer:

  • Amit Kumar MISHRA added an answer in Folate:
    Can anyone suggest some highly folate positive cancer cells?

    Please suggest about some folate positive cancer cells? Any reference having the % of folate expression will be very helpful.

  • Marcelo B. Perotoni added an answer in Waveguides:
    Why do open ended waveguides radiate? Also why is the beamwidth wide for this?

    Why do open ended waveguides radiate? Also why is the beamwidth wide for this?

    Marcelo B. Perotoni

    Hi Ray

    Balanis chapter 12, of his Antenna Book. The open waveguide (its mouth) can be seen as with magnetic currents circulating on its area. The far field pattern will be similar to the Fourier Transform of the Magnetic Current Shape, on the aperture.

    The beamwidht is wide because of the small mouth. If the mouth is made larger (as with horn antennas) the gain will be larger. You can use the scaling property of Fourier transform to understand it. Bracewell book has also a nice chapter on aperture antennas, using the same analogy.

  • Abbas Khan asked a question in ABC transporters:
    I am trying to build a homology model of ABC transporters but the problm is I hav to use modeler and I dont know how to use that Can any one help me ?

    Need modeller tutorial.

  • David Fischer added an answer in Climate Change:
    Are there authentic published work confidently pinpointing the sole anthropogenic factors contributing to Climate Change?

    Combined natural and anthropogenic factors (geologically recent phenomenon) govern Climate Change. It is, therefore, of paramount importance to discretely recognize the role of humans in Climate Change and to plan efficient strategy to mitigate it.

    David Fischer

    "(A)nthropogenic CO2 at current and projected levels is a huge forcer of climate change" is simply a restatement of what the IPCC has continually recognized in its series of several reports over many years, reflecting what the broad body of work among atmospheric scientists demonstrates.

    If anyone disagrees in a substantial way, of course, they are welcome to publish papers explaining.  We'd all welcome that, because every last human with knowledge and interest in this area—scientist or layperson, conservative or liberal, religious or not—shares the same confirmation bias: we would strongly prefer that the problem of global warming were not real and not serious.

    Syed Abbas Jafar, if you disagree with the IPCC's core conclusions about the role of fossil fuel emissions in rapidly altering Earth's atmospheric chemistry and, consequently, its global climate, please show what robust peer-reviewed research you do agree with insofar as this matter is concerned.