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  • Guido Bongi added an answer in Carotenoids:
    How do you measure Chlorophyll and Carotenoids of tomato fruits by spectrophotometer?

    How to measure Chlorophyll and Carotenoids of tomato fruits by spectrophotometer?

    Guido Bongi · National Research Council

    I meant the original method as...The contents of chlorophyll and carotenoid in tomato fruits have been analyzed respectively by different methods in a conventional way. We studied simple method for simultaneous determination of the pigments in tomato. All pigments in sample were extracted with acetone-hexane (4:6) at once, then optical density of the supernatant were measured at 663nm, 645nm, 505nm and 453 nm 

  • Daniel Elad added an answer in Bacterial Resistance:
    What is the difference between the colonies growing within the zone of inhibition(which one could term as semiresistant)and fully resistant colonies?

    Difference between semi resistant and completely resistant colonies

    Daniel Elad · Kimron Veterinary Institute

    To the best of my knowledge there is no global answer to this question. In some cases the smaller colonies may be partially resistant but in other cases this is accepted artifact related to specific bug/drug combinations.

  • Peter T Breuer added an answer in References:
    Would yo please suggest some good references on advanced researches on modulo group Zn?

    Would yo please suggest some good references on advanced researches on modulo group Zn?

    Peter T Breuer · Birmingham City University

    Sudev - what is the content of those links? Why are they of interest? What criteria have led you to form that collection and where have they come from?

    I haven't the patience to check all of them, but at least http://www1.spms.ntu.edu.sg/~frederique/lecture5ws.pdf is just the ordinary elementary group theory chapter of a 1st year u/g text book. Its high point seems to be Lagrange's theorem on the order of a subgroup dividing the order of a group, via counting the number of cosets.

  • Hanno Krieger added an answer in Radiation:
    What is the physical difference between between radiation decay mode, radiation type and radiation intensity and the physical relation between them?

    I have extracted the decay data from bnl, but I am not getting the exact difference between radiation decay mode, radiation type and radiation intensity and the physical relation between them.

    Can anyone can one help me please?

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen


    it´s like I supposed. I´ve had a look into your exel sheet. It´s a n unconventional table form of radio nuclide chart. The explanation of "decay mode" in your exel is strange. You should only use the column with the emitted particles called "emitted particles". The intensities are relative probabiöities to decay by the declared decay modus . It´s called branching. If you have a look at the example of 11C you see first line 99,79%, in the second line you see the difference to 100% 0,2217. In the third column you find the intensity for pair annihilation (beta-plus with electron) with a probability of 99,8036%.

    To explain I attend a lecture of mine. It´s in German but you will imediatly understand all the formulas. Here you can find all the explanations. To translate just use the google translator.

    The most important decay modi are:

    alpha decay: emission of an alpha particle

    beta-minus decay: converting a neutron to a proton in the nucleus and emitting an electron and an antineutriono

    beta-plus decay: converting an proton to a neutron and emitting a positron and a neutrino

    EC: electron capture mostly capture of a K-electron from the inner K-orbits and as consequence fluorescence in the atomic envelope, competition to beta plus decay

    gamma decay: deexcitation of the nucleus by emitting an gamma quantum

    inner conversion: deexcitation of the nucleus by hitting mostly of a K electron from its shell in competition to gamma decay.

    alternativley in the atomis shells AU: emission of auger electrons instead of emitting flourescence radiation from the envelope by transfering energy to neigboured electrons in the same shell.

    If you have some more questions, just send a mail.

  • Do you that researchers from the CIS with Kandidatskaya degree have to enroll in PhD studies in order to be considered 'equally knowlegable?

    As you know most until recently most researchers from Russia, Ukraine, Kazakhstan and other CIS countries qualified for Kandidatskaya degree instead of a PhD. Do you think that these degrees are equal?

  • Can anybody suggest extremely high quality separation of muscovite, biotite and quartz from a fine grained mica schist?

    I want 1) to remove quartz within biotite, 2) quartz entrapped within muscovite book 3) smaller flakes biotite from a small book of muscovite. All these are from a mylonitic metapelites.

    Uriah Alexander Lar · University of Jos

    Nirmalya! I know that quartz has a s.g. of 2.65 and muscovite of 2.76-2.88. If separating these two minerals using bromoform (depening on bromoform's density) wouldn't work, then your best bet is to use either a Shaking Table (that will again depend on the quantity of your sample) or recourse to using a Frantz magnetic separator at different voltages (the operator's guide could help you). Let me know any method that finally works for you.

  • Does anyone know how to develop predictive model using neural networks for predicting boiler emissions?

    how the neural network is trained

  • What could be the possible theory or conceptual model for a study on perception toward spectacle use?

    I want to carry out a study on children, parent and teachers perception toward use of spectacles in children. Please, who have an idea of the theory or conceptual model to be used in this study?

    Tulsi Bhandari · Pokhara University

    Try to apply HBM (Health Belief Model. But, you should identify and define individuals perception, modifying behaviours/factors and likelihood of action. Only, you can fit in the model appropriately...

  • Mohamed Hamed added an answer in Cell Line Culture:
    What can possibly cause recurrent random contaminations of cell lines?

    Within the last two weeks, I started getting random recurrent contaminations (milky like floating contamination) in my cell lines. Everything I get into the hood is sterilized (even the marker I use), I sterilize my hand every time it gets outside the hood, I change the gloves frequently, the medium sterility test is negative (I also get it randomly in one of many cell lines even though I use the same medium for all), I changed from one incubator to another but still the same, no body in the lab experienced that so far and the contaminations appear at random times, so some times one cell line is contaminated the next day after changing the medium and then another cell line three days after changing the medium (and at the same time other cell lines whose medium were changed at the same day of those contaminated look fine even though their turn for changing the medium came after the contaminated ones) and all contaminations look the same (bacterial). So its simply all random and doesn't make sense.

    Looking forward for your answers.


    Mohamed Hamed · Hochschule Bonn-Rhein-Sieg

    Thanks for your suggestions. I left one media plate in the incubator as suggested by Ron Reiserer however it turned to be negative, so I suggest it isn't a problem with the HEPA filter. Actually when I look at them under the microscope they seem like flakes of black irregular shaped things that don't move but stay still once the liquid in the flask stops moving. Also the medium becomes pinkish in color after 3 days, I think if it was bacteria it should have been rapidly consumed and turns yellow, so this still confuses me.

    Currently I rolled out the possibility that the contamination came from the filter or the material I use (since I heavily spray them before getting into the hood), so I will see if it continues or if it comes under control. I will also give it a try with different antibiotic cocktail and see how it will go.

  • Kåre Olaussen added an answer in Particle Physics:
    No experiment directly observed Quark particle, why do we think Standard Model is a valid theory?

    The Standard Model of particle physics is a theory concerning electromagnetic, weak, and strong nuclear interactions, which mediate the dynamics of known subatomic particles. The current formulation was finalized based on the existence of quarks. There is no way to proof the existence of quark. It is pretty risky to build a theory one something that may not exist. It neither explains force hierarchy nor predicts the structure of the universe. The Standard Model falls short of being a complete theory of fundamental fields. Mathematically, the standard model is a quantized Yang-Mills theory. Because of its success in explaining a wide variety of experimental results, the Standard Model is sometimes regarded as a "theory of almost everything".

    Kåre Olaussen · Norwegian University of Science and Technology

     Cao> The proton mass result in my paper has precision of 10^-9 with simple formula.

    Which paper?

  • Saif Ullah added an answer in SWAT model:
    Does anyone know about the SWAT model error "index was outside of bound of array"?

    I am simulating a SWAT model. I provide all the input data, then I write all input file, it give error "the index was outside of bound of array". If anyone knows the solution of this problem, please guide me., Thanks for your positive response.

    Saif Ullah · Hohai University

    Hi Kim,

        Yes, i solve my problem just reinstall my Swat model.I find the problem in the soil database, when i try to add my user soil in the data base.May be, you leave some blank spaces.You should check your database and input data.This error arise due to these problem. You need any information regarding to this problem, i can share with you.Welcome from my side.

  • What are the rights of refugees under international law?

    The greatest challenge facing refugees arriving in the developed world is to convince authorities that they are, in fact, entitled to recognition of their refugee status.

    Mariano Ruiz Espejo · Universidad Católica San Antonio de Murcia

    This is a preoccupation of the Popes (in Spanish):

    · http://es.catholic.net/op/articulos/28263/cat/572/garantizar-asilo-y-reconocer-derechos-de-los-refugiados.html

    · http://es.catholic.net/op/articulos/44594/cat/418/la-santa-sede-sale-en-defensa-de-los-derechos-de-los-refugiados-en-la-onu.html

    · http://www.es.catholic.net/op/articulos/15303/cat/572/el-papa-pide-respeto-de-los-derechos-de-los-refugiados.html

    · http://www.es.catholic.net/op/articulos/27997/cat/578/santa-sede-pide-mas-voluntad-politica-para-asistir-a-refugiados.html

  • Bojidarka B. Ivanova added an answer in VASP:
    Problem with Raman frequency of MoS2 Mono-layer sheet using gaussian 09 ?

    Dear gaussian 09 users,

    I would like to calculate the Raman Spectra of MoS2 Mono layer which is inside an unit cell of  dimension 8 3 1. Across the cell boundary, I have dangling bonds hanging out on each atomic sites. The no. atoms about 100. This was the structural Information of my system.

    Coming to the calculation part. The structure was optimized using VASP DFT package. Since, its an optimized structure, Should I have to optimized this here again. If so, what should be the basis set and optimization scheme.

    I am doing raman freq. calculation of this, I have selected frequency and Raman tag only and then for the BASIS set and calculation method, I am only trying with different possible combinations of it. But, it is not leading me to anywhere. Can anyone suggest me regarding the calculation scheme for this system. I will highly appreciate any suggestion and comment on this.

    Thank you.

    Note: I don't know, whether g09 handles or not, the sheet kind of system inside an unitcell.

    Bojidarka B. Ivanova · Technische Universität Dortmund

    Mr. Jena,

    When you have optimized the geometry than you can use the step 2 below:

    1. Opt:

    # RB3PW91/SDD Opt(CalcFC) Pop=(Minimal) Test

    2. Spectral analysis

    #P RB3PW91/SDD Freq=Raman Pop=(Minimal) Test

    If you have employed HF or MP2 than only 'Freq'

    More details and fre examples of calculation of inorganic crystals you can find in our recent book:

    B.Ivanova, M.Spiteller, Theoretical design for environmental sorption processes of actinides, Lambert Academics Publishing,  ISBN: 978-3-659-63487-1, Saarbruecken, 2014, pp. 1 - 268

  • Is there anyone working on nonlinear analysis TNO DIANA ?

    Convergence problem occurs during nonlinear analysis of RC frame and Infilled RC frame. Is there anyone working on nonlinear analysis TNO DIANA and same type of work ? 

    Imrose Bin Muhit · Chung-Ang University

    I think article titled, "Practical Recommendations for Nonlinear Structural Analysis in DIANA" by Kesio Palacio can give you some idea about Convergence problem during nonlinear analysis by TNO DIANA.

    Paper Link Provided !

  • What is meant by "orientalism is a style of thought based on an ontological and epistemological distinction" made between the east and west?

    Edward Said in his introduction to Orientalism (1978) says this....what colud be the ontological and epistemological distinction between east and west?

    Douglas R. Daugherty · University of New Mexico

    Dear Barjinder,

    I would agree with Mr. Sayar in some sense but my take on what Said was really talking about how we, (Western European intellectuals) constructed the Oriental. Hence the terms "Orientalism". Said book demonstrates without much doubt that how the Orient was viewed was socially constructed through the elite academics of the West by way of propaganda.

    At the most fundamental level Said points out the fact that how the west viewed itself as the civilized, educated, beautiful, ect was based on what was termed to be the difference in the oriental.

    In other words what was felt to be uncivilized, distasteful, exotic, and uneducated was the Orient and in effect or by default what was civilized, beautiful, proper became the occidental or the west.

    This is how the Orient and the West became, (i.e. its ontology) and how education and science was done became the epidemiological distinction.

    I would also suggest reading the Rise of the Universities I cannot recall the author but the book points out the distinction or the uniqueness of the Wests University System.

    I hope this helps,


  • Ellison Mane added an answer in Managment:
    From HRM perspective what principles do school systems apply to managing teacher performance?

    Public schools have a responsibility to their community in preparing children to become a good citizen, productive employees and smart consumers. However, they are not producing the result expected of them.

    Ellison Mane · University of the South Pacific

    Thanks all for your thoughts and insight, they have been very helpful.


  • Daniel Elad added an answer in Plant Extracts:
    Can we use the expired antibiotic disc for disc diffusion test?

    I want to screen the antibacterial activity of the plant extract. and i will be used tetracycline or ampicilin drug as the positive control.  However, the one that i have right now is already expired. Can I still use it in the test? Thank you.

    Daniel Elad · Kimron Veterinary Institute

    If your lab is working under ISO quality control, you're not even allowed to keep them in you refrigerator. As to comparing of expired disks to non-expired ones this may be acceptable but ask yourself the following question: if you were (God-forbid) the patient, would you like to be treated with an antibiotic whose activity was determined by an expired disk even a validated one? 

  • Marc Tessera added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.


    You didn't answer my question: what is your explanation of the two different consciousnesses in split-brain patients?

  • Alfonso Prado-Cabrero asked a question in HPLC Metering head:
    Does preparative metering head in HPLC cause unnecesary dead volume if you inject low sample volumes?

    The metering head of my Agilent HPLC 1200 is a 900 ul (200 bars). I´m injecting 10 ul of sample only, so I´m wondering whether I have a lot of unnecesary tubing in my system.

    In fact, peaks are not well resolved in this HPLC. Could it be due in part to this preparative head? I know that there are much more factors affecting separation, but separation is better in our 1260. I´m afraid that the long 900 ul loop is affecting. I got 2 contradictory advices from Agilent support, so I would appreciate more advice. Thanks.

  • How do I develop a health index for a bearing condition classification?

    Statistical features extracted from the wavelet coefficients are reduced using Kernal -Fischer's discriminant analysis. The reduced features must be used to classify the four conditions of bearing. can any body suggest me the metod to develop health index

    Hayder Dibs · Putra University, Malaysia

    really thanks to both of you

  • Is there any information on linear ordered topological structures?

    Could linear ordered topological structures, I am looking forwards to expertise this fileld which became actual since falling past XX, be related to your subject I believe, differential geometry? Just can find Differential Manifolds, Brickell F. and Clark, R. S. in my library say, times where I was a student ... Thank you.

    Yuriy Borisovich Zelins’kyi · National Academy of Sciences of Ukraine

    You cfn see J. Math. Soc. Japan
    Volume 9, Number 1 (1957), 131-142.
    Topological structures in ordered linear spaces.
    Ichiro AMEMIYA and Tuyosi MORI

  • David Darchiashvili added an answer in Morality:
    Hello everyone, is there such a thing as morality in the international arena?

    Hans Morgenthau has an interesting take on this, but I am a bit confused by his stance.

    David Darchiashvili · Ilia State University

    Studying politics, as well as being involved in it personally, I can say that general considerations of morality do not easily apply to this field. Here you have to serve the"polity" and if you serve efficiently, you are a moral person. Although, it does not mean that ends justify means. wrong means would eventually ruin your ability to reach the goal

  • Maykel Manawan added an answer in XRD Analysis:
    What is the interpretation of humps (broad peaks) in a XRD pattern which repeat themselves in a exact range?

    We are using RF magnetron sputtering for coating VANADIUM (30-50nm) on various types of substrate. After obtaining the XRD results, there are two humps with wide range. Despite their different intensity in different samples, they have quite exact points for rising and falling in every cases. So I don't think that they are due to amorphous property of sample. These humps also are independent of grain size of coated vanadium since the AFM images shows different grain sizes for different samples, while there is no change in the hump ranges.

     Attached, there is a XDR pattern of one of the samples to show these humps.

    Later attached: XRD patterns for naked Si, SiO2/Si substrates and XRD system configuration details.

    Maykel Manawan · University of Indonesia

    @Gertz, it's the peak of Si {001}, because Si wafer is single crystal it doesn't appear after rotate 45 and 90. In-plane diffraction can reveal the other parallel peaks.

  • Global layer on solar radiation?

    Does anybody know an openly accessible source of global solar radiation, at a resolution of 1 kilometer?

    Hannes Gaisberger · Consultative Group on International Agricultural Research

    As I already suspected there is no global GIS layer with 1 km resolution freely available at this moment. Thank you in any case for your answers and suggestions

  • There exists loss meaning for Def about belonging of point(m/x) in multiset. I would like to know your opinions about belonging and distinct m-points?

    Let M={2/a,3/b,1/c} be a multiset

    1) Is 1/a \in M ? although {1/a} is sub-mset of M.
    2) What is the meaning of different multi-point ?

    Yuriy Borisovich Zelins’kyi · National Academy of Sciences of Ukraine

    Please give me a definition of multiset. What values for a,b,c?

  • Kaushik Bhattacharjee added an answer in RID:
    How to get rid of the multiple non-specific bands of pcr?

    I'm using a CG rich primer to amplify a DNA sequence, and I'm having the multiple non-specific bands problem; I've tried to use the two step PCR as suggestions, it reduced the intensity of the non-specific bands but I didn't get rid of them, and they're appearing sometimes in high intensity! anyone could help me for the best solution for this problem? any suggestions ?

    Ps. the thick band in the picture below is my expected pcr product size (270pb) and this is a 100pb ladder , the other bands are non-specific.

    Kaushik Bhattacharjee · North Eastern Hill University

    As per your provided information, it's seems that these are non-specific amplification. First of all, try to work on your primer pair. You can opt for touch-down PCR for these non-specific binding of primers. As mentioned by Dr. Artur, follow the suggestions given in RG threads.

  • Barry Turner asked a question in Medical Ethics:
    Is 'discretion' incompatible with truth?

    According to Pascal...

    "the first rule is to tell the truth; the second is to speak with discretion"

    Can such a confused position really be axiomatic in medical ethics?

  • What are consequences of living in a warming World?

    Human activities are changing the composition of our atmosphere
    at an unprecedented rate.

    Luca Marescotti · Politecnico di Milano

    During the last period Holocene, we know seasons, winds, weather. Clima was in a friendship with humans. We don't know what will be global change drived by humans, what kind of future brings us.
    Maybe some radical change à la René Thom (catastrophe theory)
    Please, see: Stockholm Resilience Centre and Planetary Boundaries.
    There is also a very interesting TEDconference by Johan Rockström (executive director of the Stockholm Resilience Centre).

  • Daniele Sasso added an answer in Mesons:
    Can the time dilation be proven with the life of the flying mesons?

    Einstein's time dilation is determined with t’=t(1-v^2/c^2)^1/2. It is thought that the time dilation is confirmed with that the life of the flying mesons is longer than that at rest.

    However, this is not true.

    First, there does not be the stationary meson. Any particle is always moving. There are only the faster and slower moving mesons.

    Second, no experiment for explaining the time dilation determined that what speed was used to distinguish the slower mesons from the faster ones. Or, in another word, are there the slower mesons? And, how much is the difference of the speeds between the slower and faster mesons?

    Third, if there were the slower and faster mesons, the mesons are decaying according to a certain law. Thus, the life of some of the slower mesons is longer than that of parts of the slower ones. And, for the same reasons, the life of some of the faster mesons is longer than that of parts of the faster ones. Therefore, no life of both the slower and faster mesons is accordant with t’=t(1-v^2/c^2)^1/2.

    Daniele Sasso · Progetto Indipendente ARS

    I observe in preceding comments five different reference frames are considered: own rest reference frame of muon, the reference frame of slow muon, the reference frame of fast muon, the reference frame of laboratory, the moving reference frame with speed v. It would seem for all five reference frames the Principle of Relativity is valid. The Principle of Relativity nevertheless has no relation to time changes, but those changes would be generated only by Lorentz's transformations. Besides there is no direct experimental test of measurement of those changes but only indirect measures of the speed for which the same theory, and not the experiment, proves its own validity. With regard to elementary particles we are able to measure directly only decay lengths and indirectly speeds as per results of preferred theories. It is insufficient  to be defined an experimental confirmation. Besides in order to avoid easy confusions I would advice to make use of only two reference frames each time.          

  • Is the Riemannian geometry consistent?

    In the Riemannian geometry the distance between any two points is defined as an integral along the shortest curve (geodesic), connecting the two points. Let the Euclidean geometry be defined on two-dimensional plane L as a Riemannian geometry. Let now we make a hole in L and obtain the plane Lh with a hole. Then the plane Lh will not be imbedded in L isometrically. Does it mean, that the Riemannian geometry is inconsistent? Or following mathematicians, one should consider the Riemannian geometry as a consistent geometry, provided one considers only convex pointsets.

    Yuriy Borisovich Zelins’kyi · National Academy of Sciences of Ukraine

    It seems to me that the answer of miss Eliza Wajch is the best.