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  • Victor Ostrovskii added an answer in Cosmology:
    What are some of the models of dark matter using a scaler field?

    What are some alternative models of dark matter as a scaler field using an approach similar to one found in the paper http://arxiv.org/pdf/1504.04037.pdf?

    Victor Ostrovskii

    Dear All,

    The present cosmology is in the crisis state. I think that each reasonable person, if he personally didn't participate in the formulation of the today disgracefulness, cannot be dissenting with this statement. Just therefore, numerous particular hypotheses trying to explain any unit phenomenon in isolation from an all-inclusive cosmological theory flourish.

    At present, only one comprehensive intrinsically-noncontradictory cosmological theory exists, and this is the PFO-CFO Theory. In its ground, the principle "everything - from something" and Einstein’s conclusion on the common essence of the mass and energy are laid as its basis instead of the fantastic principle "everything - from nothing", which is in the basis of the today cosmology. 

    Everybody, who is really interested in the creation and development of a new theory, which is capable of giving new explanations for the Universal processes and phenomena from the "Beginning" up to the future of the Solar System and including simple explanations of stars formation, elements formation, formation of the Solar System, nature of the protuberances and solar wind, nature of the 11-year cycles of solar activity, transformation of the solar magnetic moments, etc., I advice to familiarize yourselves with the PFO-CFO Theory , beginning from my answers to the question by Elena Kadyshevich at the ResearchGate site by the address https://www.researchgate.net/post/Einsteins_relativity_what_is_eternal_questionable_and_erroneous_in_the_starting_points_of_the_theory_and_in_the_subsequent_conclusions_from_it  ) and then to read our publications on different aspects of the theory from publications of 2015 to earlier ones at my or Elena Kadyshevich RG pages. I call you to discuss and develop new theories rather than to mend and repair the aged 100-year-old theory, which is based on arbitrary fictions.

  • Taha A Azim M A Razek added an answer in Manganese:
    What are the specific areas which are contaminated with manganese in soil??

    Manganese soil toxicity

    Taha A Azim M A Razek

    Dear Rajpoot, There are many reason to have soil contaminated with Mn, first of all abandoned manganese mine, second, dust fall from ferro manganese plant , third disposal of Fe/Mn from ground water drinking plants.

  • Maathangi Murali added an answer in Hela Cells:
    HeLa cells are not sticking to coverslip?

    Hello guys

    Well I am having problem with my HeLa S3 cells. I do not know why they are not sticking to the coverslip when I seed them in a 6 well plate. I am seeding 5 x 10*5 to 10*6 cells in a 2 ml RPMI supplemented with 10% FBS. After few days of incubation, I can see some cells attached on the coverslip but they do not look happy and stretched as they usually do.

    I can also see cells sticking happily to the well surface but not to the coverslip. 

    Anyone had this problem before.

    Thanks in advance for your support. 

    Maathangi Murali

    Some surface treatments can be done for coverslips so that the cells get attached to the coverslips

  • Soumendra Darbar added an answer in Childhood Obesity:
    Are there any effective medicines for treating childhood obesity?

    Any other effective drugs except metformin which is approved for pediatric patients 10 years of age or older with type 2 diabetes? 

    Soumendra Darbar

    Yes, Metal based nanomedicine are partially helpful for childhood obesity and that could reduced oxidative stress.  

  • Milad Nimi added an answer in Applied Kinesiology:
    In front flip movement, what is the best time for raising the knees up during the jumping from floor?

    actually,this movement occurs in a little time and we should have best landing. for example in the athlete person with normal specification , in which height of entire jumping, the athlete should raising the knees up? or when the athlete do this of movement total time?

    Milad Nimi

    Dear Sina

    Your question is so general, If you want to find about the details of your question and how you can solve it please read the attached paper.

    Best regards,

    Milad Nimi

  • Süleyman Serdar Karaca asked a question in Enterprise Risk Management:
    The Effect on Firm Value of Enterprise Risk Management: May I link the between Firm Value and Enterprise Risk Management Which methods can I apply?

    Which Variables can I choose as Enterprise Risk Management?

  • Minoo Alizadeh added an answer in Nanostructures:
    Do you have any idea on how it is possible to improve the conductivity of Al wire with the help of Carbon nanostructures?

    Hi everyone, I am seeking to prepare viscose solution of Carbon nanostructures using which I will be able to coat Al wire in order to improve its conductivity. I tried aqueous solution of CNTs and I came across some problems. It was not viscose enough to provide a good coating.I would deeply appreciate it if anyone could help me with it. Any related articles or references can be also of great help.

    Minoo Alizadeh

    I see...

    I deeply appreciate your invaluable help.

  • Thulani Dube asked a question in Harmonics:
    Can boardrooms ever be harmonized in South African listed companies?

    Can boardrooms ever be harmonized?

  • Faris Alshubiri added an answer in Impact Assessment:
    Is there any way to calculate one risk value from different criteria?

    The problem goes like this: I have to evaluate quantitative risk from 8 impact criteria put it on a map.

    The impact is assesd like this: I have deceased (nr of people), wounded (nr of medical records), evacuees  [ nr of people * nr of days], people without access to basic services [nr of individuals in shelters* nr of days], environmental impact [affected area of the protected zone (%) * nr of affected species * nr of recovery years], economic impact (euros), social impact (nr of people without daily services acces*nr of days without access) and psychological impact (psychological index). 

    To evaluate it qualitatively is relatively simple. I have a different scale for impact for each criterion and I assume each level on the scale has a certain value associated (1-5 form very low to very high). All I have to do is to calculate the average and I get the global impact which is translated as risk. 

    What I don't know is how to calculate the global impact quantitatively. Is there any scientific formula/method that does that? Do I need a vector with all the 8 criteria as attributes or is there any way to get one single composite value form all of them? 

    Thank you! 

    Faris Alshubiri

    Dear Cristina Vrinceanu

    See the web site http://www.riskencyclopedia.com/articles/var_measure/

    may be help you about your question 

    Best Regards,

  • Hisham Mohamed asked a question in Microbial Fuel Cell:
    What are the problems of using urine specifically in Microbial Fuel Cells to generate electricity?

    I am having some difficulty in identifying what are the operational parameters for using urine in Microbial Fuel Cells to generate electricity. I have read articles that this type of technology can be implemented in toilets at refugee camps to help power lighting. There are many articles regarding the problem in the material used for MFCs, but not so many on the fuel source. So what are the factors that are considered when using urine as the fuel source? 

  • Jacek A Koziel added an answer in IAA:
    Quick detection method of isoamyl acetate production by yeast?

    I'm interested in screening a large number of yeast for the production of isoamyl acetate. I'm searching for a quick, semi-quantitative, ideally visual (perhaps colorimetric?) method to find some yeast that produce varying amounts of IAA. Production of IAA can then be confirmed later by GCMS detection.

    Suggestions for either direct or indirect detection methods welcome!

    Jacek A Koziel

    Hello Chris - we developed quantitative method for isoamyl acetate (IAA) (and a handful of organic impurities in industrial grade ethanol using headspace extractions with solid-phase microextraction (SPME).  Of course, one could use SPME for quick headspace screening, qualitative extractions and analyses on GC-based instrument.  SPME headspace extractions could be automated as well. We used the Carboxen/PDMS 85 um coating that worked well for 10 target compounds (including IAA).  The method detection limits for IAA in ethanol was ~ 1.4*10^(-6) mol/L, using 20 sec headspace extractions from 10% diluted ethanol samples. 

    The recent publication on the use of this method is:

    Onuki, S., J.A. Koziel, W.S. Jenks, L. Cai, S.Rice, J. (Hans) van Leeuwen, Ethanol purification with ozonation, activated carbon adsorption, and gas stripping, Separation and Purification Technology, 2015, 151, 165-171, http://dx.doi.org/10.1016/j.seppur.2015.07.026.

    I hope it is helpful.


  • Nabil Ismael added an answer in Shear Strength:
    Why shear strength decreases with increasing number of wetting-drying cycles?

    The shear strength behaviour of natural soil sample decreases with increasing the number of wetting-drying cycles. The decreasing trend of cohesion is more then the friction angle. After 4 wet-dry cycles, the values are almost stable.

    Can you give me some clear idea " why shear strength decreases due to number of wetting-drying cycles"?

    Nabil Ismael

    You did not indicate the classification of the soil  you have (silty clay,clayey silt or cemented sand??)  . However,  if fine particles, acting as cementing agents, are removed due to the wetting and drying cycles it could result in a reduction of cohesion with minor effect on the friction angle.

    You may read some of my papers on the leaching effect on the strength and compressibility characteristis of arid climate soils.

  • Panagiotis Stefanides added an answer in Mathematics:
    Is the beauty of patterns or are the structures in patterns the most important source of mathematics?
    It was observed in an earlier thread that G.H. Hardy made the following
    observation in his 194o book A Mathematician's Apology:

    "The mathematician's patterns, like the painter's or the poet's, must be beautiful, the ideas, like the colors or the words, must fit together in a harmonious way. Beauty is the first test; there is no permanent place in the world for ugly mathematics...It may be very hard to define mathematical beauty, but that is just as true of beauty of any kind-we may not know quite what we mean by a beautiful poem, but that does not prevent us from recognizing one when we read it."

    The main issue for this thread is whether beauty or structure comes first in doing mathematics. In terms of structure, consider

    A mathematical structure is a set (or sometimes several sets) with various associated mathematical objects such as subsets, sets of subsets, operations and relations, all of which must satisfy various requirements (axioms). The collection of associated mathematical objects is called the structure and the set is called the underlying set. http://www.abstractmath.org/MM/MMMathStructure.htm

    For example, a set endowed with a proximity (nearness) relation acquires a structure, namely, collections of near sets (each collections contains all sets that are near a given set in a proximity space). Any set endowed with a relation has a structure. Then the question here is Do we first look for structures when we do mathematics?

    The question here is not whether mathematics is beautiful but rather whether beautiful patterns are the starting point of mathematics. For example, is it the painting Mona Lisa or the golden ratios in the painting that first attracts us? See the attached image.
    Panagiotis Stefanides

    >...Dear colleague @Panagiotis has many articles related to beaty...>

    Dear Ljubomir.

    Very kind of you.

    Thank you.

  • Niranjan Biswal added an answer in Porous Materials:
    Can anyone help me with the calculation of BJH isotherm?

    I would like to get an idea about the calculation of pore size distribution using BJH isotherm. I am attaching the relative pressure (P/P0) and amount adsorbed got for my sample.

    Niranjan Biswal

    Simply you can got from the Instrument and also manually you can got from the ASAP 2020 Micromeritics manual.

  • Hamida Darwish added an answer in Band Gap:
    Do the bandgap changes with the extension of absorption edge at higher wavelength side?

    Dear Scholars,

    I have observed change in the absorption tail for the samples with three different compositions. With increase in doping  concentration absorption tail is extending as shown in attached file. However, band edge position remains at the same position. I am curious to know whether change in the absorption edge is due to change in band gap or something else? Which method is accurate for bandgap calculation by absorption data.



    Hamida Darwish

    No the band gab Shouldn't change 

  • Giorgio Giardina added an answer in Crystallization:
    What is the affect of pH on crystallization process ?

    I am thinking to change the pH of the super saturated solution, will that help growing any crystals? ( in general ) 

    and if so , will it affect my complex??


    Giorgio Giardina

    Ok Farah,

    that's a bit more information, pH will certainly affect the dissociation constant of your complex. However, if you are getting small crystals your not so far. I don't know which crystallization method you are using, but to go from many small crystals to few big ones, you need to slow-down the nucleation process, that is when your crystals start to form the initial nuclei which will then grow into visible crystals. Lower the complex concentration, and/or the precipitant concentration, and/or the temperature (try 4˚C).


  • Alemayehu Duga asked a question in Magnesium:
    Beside the Anti-convulsion use of magnesium sulphate it is believed to decrease cholesterol synthesis & as stress reliever. what is its mechanism?

    Magnesium sulphate, cholesterol , stress

  • Leon Eyrich Jessen added an answer in R:
    How can I get Cut-Off, Sensitivity and Specificity from multiclass.roc in R?

    I am using thefunction multiclass.roc from pROC (R) to perform a multiclass ROC curve but this function only delivers the AUC. I would like to have the coordinates as well, Cut-Off, sensitivity and specificity, do you guys know how to get this information?

    I also work with SPSS but I don't know untill now that SPSS supports multiclass ROC curves.

    Leon Eyrich Jessen

    For a predictive model the AUC gives an estimation of the overall threshold independent performance. Sensitivity and specificity on the other hand are threshold dependent. Hence if you need to know the sens and spec, then you'll need to choose a threshold and then compute the measures.

  • Qurban Ali asked a question in Bromides:
    Can i use use water and lithium bromide solution for cooling purpose of engine?

    can i use solution of water and lithium bromide for cooling purpose of engine?

  • Diane Gamache added an answer in Cognitive Architectures:
    Other than Kosslyn, are there any other prominent researchers concerned with visual-spatial reasoning?


    I develop and maintain the CHREST (Chunking Hierarchy and REtrieval STructures) cognitive architecture and have recently developed functionality to allow the architecture to use coordinate-based visual-spatial reasoning to "plan ahead" along with other behaviours.  In doing this I've become interested in how the mind actually handles visual-spatial reasoning, particularly coordinate-based visual-spatial reasoning.  I'm looking for research that details human data with regard to this topic with a view to having CHREST "fit" this data and see if any predictions can be made by the architecture.

    Many thanks for any help that anyone can provide! 

    Diane Gamache

    I am developing a coordinate-based visual-spatial reasoning framework by transposing to the video analysis side by side the "Aspecto-Temporal Representation for Discourse Analysis approach : An example for computation" (Jean-Pierre Descles and Hee- Jin Ro, 2011)


  • Shivam Singh added an answer in Principal Component Analysis:
    Can someone suggest a good free software for Principal Component Analysis?

    There is lot of interest for Principal Component Analysis among researchers in sciences. What would be a good free software for use of this community?

    Shivam Singh

     You can also use PC Ord software which is more user friendly.

  • Mihai Prunescu added an answer in Numbers:
    Do you know examples of first order sentences true in Q and C but false in R?

    I was looking for examples of first order sentences written in the language of fields, true in Q (field of rational numbers) and C (field of complex numbers) but false in R (field of real numbers). I found the following recipe to construct such sentences. Let a be a statement true in C but false in R and let b be a statement true in Q but false in R. Then the statement z = a \/ b is of course true in Q and C, but false in R. 

    Using this method, I found the following z:=

    (Ex x^2 = 2) ---> (Au Ev v^2 = u)

    which formulated in english sounds as "If 2 has a square-root in the field, then all elements of the field have square roots in the field." Of course, in Q the premise is false, so the implication is true. In C both premise and conclusion are true, so the implication is true. In R, the premise is true and the conclusion false, so the implication is false. Bingo.

    However, this example is just constructed and does not really contain too much mathematical enlightment. Do you know more interesting and more substantial (natural) examples? (from both logic and algebraic point of view)

    Mihai Prunescu

    Paul, purely universal sentences are true in all substructures. Also, purely existential sentences are true in all overstructures. So because Q \subset R \subset C, a purely universal sentence true in C will be true also in R and Q, and a purely existential sentence true in Q will be also true in R and C. So we must look for sentences given by some more complicated prefix (at least AE or EA) followed by a conjunction of negated or positive atomic formulae. (also our examples so far have more complicated prefixes...)

  • Leon Eyrich Jessen added an answer in Enzymology:
    Is it possible to predict the active sites of an enzyme with out knowing the ligand ?

    PDB provides ligand information, but what about the proteins not submitted to PDB, is there any way to get active site information with out using ligand  ???????  Please suggests online tools or soft wares which you have come across and got the results. I mean not the website like scibio-iitd, COFACTOR, FINDSITE, Concavity etc.

    Leon Eyrich Jessen

    Hi Kamal,

    If you have done random mutational studies and thus have a number of variants of the same protein and then the measured catalytic efficiency for each variant, then you can use the SigniSite server to perform an automated statistical analysis of residue-to-efficiency association.


  • Pramod Raichurkar added an answer in Fiber:
    What is the basis for characterizing fiber to be 'short fiber' in composite materials?

    I am looking for fiber size range that qualifies to be called as short fiber (away from being particle on one end and long fiber on the other) in composite materials. Since the glass-fiber reinforced ABS component being thin in size (about 3 mm) I would like to limit the fiber size.

    Pramod Raichurkar

    Any new fibre  composite strength multiplies due to the bonding force between  fibre and resin.Bond formation depends on  FTIR test  and it will give the exact  chemical structure and its strength.  Fibre length will not matter in this new composite but  linear chain molecule  should be anisotropic and should form perfect  bond with resin. Here fibre is not going for spinning weaving or knitting. It forms composite by Non woven techniques.  New covalent bond between resin and fibre determines strength of the Non woven. 

  • Hamdon Ali Abdelrhman Mohammed asked a question in Carbon Sequestration:
    I wanna know how to quantify carbon sequestration and emission for fibre crop production& what are the most simplest and recent models and equations?

    I wanna know how to quantify carbon sequestration and emission for fibre crop production& what are the most simplest and recent models and equations?

  • Yulia Klymchuk added an answer in Dramaturgy:
    Can anyone help me to define the main concepts of Wendy Wasserstein's dramaturgical discourse?

    Can you help me to define the main concepts in Wendy Wasserstein's dramaturgical discourse?

    Yulia Klymchuk

    Thank you very much!!! If you need a help ask me please)

  • Giacomo Patrizi added an answer in Computer-Assisted Diagnosis:
    Any solutions for aided pathologic diagnosis?

    I'm going to develop a software to do computer-aided pathologic diagnosis in medical field. But I'm not sure if there is any exsisting good solutions for this. Does anyone know about this? Please tell me or give me some references. Thanks a lot in advance!

    Giacomo Patrizi

    Dear Morgan,

    May I draw your attention to some papers and the underlying algorithm which solves them accurately.

    The algorithm executes what you indicate in a formalized approach   with a very high precision rate of correct diagnoses. The algorithm called T.R.A.C.E. ( Total Recognition by Adaptive Classification Experiments)  in medical diagnoses, simple microscopy, phase contrast microscopy and immunofluorescence use and taxonomic approaches such as in Alzheimer disease, so the approach will certainly be of interest to José Luis García Vigil.

    Please examine the papers indicated and explore my database in Research Gate to find additional more precise diagnostic results.

    I am at your disposal to provide fuller information on the algorithm and we can also collaborate to apply T.R.A.C.E.  to your data and pathologies that you would like to recognize with a view so that you can apply it independently.


    Giacomo Patrizi (Jacopo)

    Article: Operational research techniques in medical treatment and diagnosis: A review
    F. Bartolozzi · A. de Gaetano · E. Di Lena · S. Marino · L. Nieddu · G. Patrizi
    European Journal of Operational Research 03/2000; 121(3-121):435-466. DOI:10.1016/S0377-2217(99)00017-X
    Article: Formal methods in pattern recognition: A review
    Luciano Nieddu · Giacomo Patrizi
    European Journal of Operational Research 02/2000; 120(3-120):459-495. DOI:10.1016/S0377-2217(98)00368-3
    Chapter: Diagnosis of Alport Syndrome by Pattern Recognition Techniques
    Giacomo Patrizi · Gabriella Addonisio · Costas Giannakakis · Andrea Onetti Muda · Gregorio Patrizi · Tullio FaraggianaChapter: Clinical Analysis of the Diagnostic Classification of Geriatric Disorders
    Giacomo Patrizi · Gregorio Patrizi · Luigi Di Cioccio · Claudia Bauco
    Article: Pattern recognition methods in human‐assisted reproduction
    G. Patrizi · C. Manna · C. Moscatelli · L. Nieddu
    International Transactions in Operational Research 06/2004; 11(4):365 - 379. DOI:10.1111/j.1475-3995.2004.00464.x
    Article: Experimental results on the recognition of embryos in human assisted reproduction
    C Manna · G Patrizi · A Rahman · H Sallam
    Reproductive biomedicine online 05/2004; 8(4):460-9. DOI:10.1016/S1472-6483(10)60931-5 

  • Remi Cornwall added an answer in Big Bang:
    Are particles created from the energy released during the Big Bang? During expansion, does the energy continuous converted into matters?

    We have learnt from the big bang cosmology that all the particles was created after the big bang explosion. My question is that whether these particles was created from the energy released due to the big bang? If yes, the energy density must be decreases during the course of expansion as it is continuously converting into masses or matters. Again if it happens so, the mass of universe must be increasing with time or expansion.

    Please some give some light on it. I'm working on a solution of Einstein's field equations and I got an expanding solution with an initial singularity. As the time increase to future, its mass and radius increases. So I need to explain the increase in mass with time.

  • Paul Stephens added an answer in Pain:
    Why is there patellar femoral pain after running?

    why is there patellar femoral pain after running?

    Paul Stephens

    Hello Chung

    I think knee pain, which as a runner, I have suffered intermittently, is not always easy to diagnose. That said, you might find some pointers in the following article:


    In my case, I suspect that fast interval running may have been a precipitating factor. Best wishes and good luck, Paul

  • Oana Mihaela Stoleriu added an answer in Tourism:
    Is there a case study for festival tourism?

    Festival impacts are noted within the literature and so too are the impacts of tourism.  However, I am looking to see if there are any papers which specifically address the impacts of 'festival tourism'.  A case study approach, perhaps.  If you can guide me to any published (or unpublished) work, it would be appreciated.  I am actively searching for material, so if I find some resources whilst waiting for a response, I will add them to this post for others to view.

    Please note, I am looking for specific festival tourism impacts, not generic festival impacts or tourism impacts.

    Thank you in advance!

    Oana Mihaela Stoleriu

    A case study: Rebecca Anne Curtis (2010) Australia's Capital of Jazz? The (re)creation of place, music and community at the Wangaratta Jazz Festival, Australian Geographer, 41:1, 101-116