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  • Tamer Elgebali added an answer in Cultural History:
    Is "budal" an arabic word?

    Any Arabic speakers who would help me find out what does "budal" or "bodal" mean? I found it in a ancient document and I think it is a channel or a leat, near a watemill. 

    Tamer Elgebali

    This word has no meaning in Arabic, but maybe the word is a name of a person if this person from Yemen or the Maghreb
    However, the context is important for understanding the meaning

  • Gireesan Krishnapisharoti added an answer in Prostitution:
    What are some of the community needs of women who work as prostitutes in the sex industry?

    Educational, emotional, policy and legislation, housing, medical care? Can anyone add to or expand on these?

    Gireesan Krishnapisharoti

    Most of the prostitutes in sex industry may be feeling an isolation in the society, due to various reasons. They may not be taking part in the social functions being organised and are generally feel themselves 'marginalised' in the society. This social isolation may move to the next generation as well. Having interactions with some of those in the field as a researcher, I strongly felt that they wanted a 'decent living' for their children, better education facilities, health care, employment, etc. More importantly a 'social acceptance' to their children, apart from the social identity of the mother, is one of the prime needs. It hurts them much when their children are deprived of opportunities owing to their 'social status'. What they expect, want and demand from the society for themselves and their children is 'nothing but respect as a human being' and a decent living conditions in a harmonious society for them and them and their family members.

  • Phuong X. Pham added an answer in Analytical Instrumentation:
    Ayone can suggest a technique to vaporize multi-component liquid fuels (e.x. kerosene, diesel, & biodiesel) without breaking their molecules?

    I would like to vaporize multi-component liquid fuels such as kerosene, diesel or biodiesels. Can anyone advise?

    Phuong X. Pham

    Dear Xuantian Li,

    I love your answer. Thanks so much.

    Have you reported anything related to this? If you have, can you please share with me.

    Also, with a multi-component liquid like diesel, the boiling/flashing points of its components can vary significantly. Thus, multi-stage heat ex-changer may be needed to eliminate the fuel's decomposition?

    Thanks and regards,

  • Peter Oluwole Ajewole added an answer in Web Development:
    What are free online courses for learning game development, android development, web development, big data technologies and so on ?

    What are free online courses with certification for learning game development, android development, web development, big data technologies and so on ?

    Peter Oluwole Ajewole

    You can try alison.com

  • Stephen Hillier added an answer in Soil Analysis:
    Is there a way to "guess" the minerals present in a soil based on the soil's proportion of elements?

    I used an XRF to determine the elemental composition of my soil samples. I am trying to see if there is an excessive amount of magnetite or hematite present within the soil due to nearby coal combustion, but the results only gave me the elements present and not the minerals. My resources are limited, so I need to make do with what I have. I've tried using minsq, CIPW, and IGPET spreadsheets to make an educated guess as to what my minerals are, but they don't seem to be quite what I need as they call for the actual minerals and not just the elements. (Also, if software is recommended please make it cheap/free.)

    Stephen Hillier

    As indicated in other answers you need a direct technique like XRD to determine the form of Fe.  There are various ways to calculate a mineralogical composition from chemical data like XRF, but many assumptions will be required and I doubt you can answer the specific question you are trying to answer here, 'how much magnetite, how much hematite' with chemical data alone.    If you only have access to XRF then probably your best option is to compare Fe content in areas where you expect Fe-oxides might be increased with areas where they ought not to be, so look for patterns, though this will not tell you what form the Fe is in it might be possible to determine if levels are elevated or not in relation to the location of the industrial activity.

  • Charles Francis added an answer in Astronomy & Astrophysics:
    An old question that is still fresh: Is gravity a Newtonian force or Einstein space-time curvature?
    No gravitational wave was measured yet, no graviton was detected accordingly. On the other hand no space- time curvature was observable. There is no successful experiment to validate the current theories. What is the nature of the mysterious gravity? What is the velocity of this effect ?
    Charles Francis

    Nothing cheap here Valentin, or at least no cheaper than researching black holes in a potato patch.

  • Renaud Lancelot added an answer in Contingency Tables:
    What is the best way to calculate Confidence levels for proportions in a 4*8 crosstab?

    I want to calculate a 95% CIs for the cell proportions in a 4*8 contingency table, however, I am not sure what is the best way to do this? Any good advice? I would prefer to do it in SPSS or R.

    Many thanks in advance!


    Renaud Lancelot

    If you mean percentage of the grand total, simply divide the results (predictions) by the grand total N. Alternatively, you can use an offset term in the Poisson model (= log(N)) and predict for new data with N=1.

    > t(xtabs(fit ~ x1 + x2, data=dfr) / sum(dfr$y))
    x2 a b c d
    A 0.005909389 0.007222587 0.011818779 0.009192383
    B 0.013788575 0.019697965 0.016414970 0.011162180
    C 0.013788575 0.024950755 0.022980959 0.023637557
    D 0.026920552 0.024950755 0.033486540 0.032173342
    E 0.032829941 0.030203546 0.029546947 0.033486540
    F 0.036112935 0.045961917 0.040052528 0.035456336
    G 0.040052528 0.045305318 0.045961917 0.047275115
    H 0.057780696 0.052527905 0.056467498 0.072882469

    or using an offset

    > dfr$N <- sum(dfr$y)
    > fm2 <- glm(y ~ x1 * x2 + offset(log(N)), family=poisson, data=dfr)
    > New <- expand.grid(x1=letters[1:4], x2=LETTERS[1:8])
    > New$N <- 1
    > pred <- predict(fm2, newdata=New, se.fit=T, type="link")
    > dfr$fit <- exp(pred$fit)
    > dfr$lo <- exp(pred$fit - 1.96 * pred$se.fit)
    > dfr$hi <- exp(pred$fit + 1.96 * pred$se.fit)
    > t(xtabs(fit ~ x1 + x2, data=dfr))
    x2 a b c d
    A 0.005909389 0.007222587 0.011818779 0.009192383
    B 0.013788575 0.019697965 0.016414970 0.011162180
    C 0.013788575 0.024950755 0.022980959 0.023637557
    D 0.026920552 0.024950755 0.033486540 0.032173342
    E 0.032829941 0.030203546 0.029546947 0.033486540
    F 0.036112935 0.045961917 0.040052528 0.035456336
    G 0.040052528 0.045305318 0.045961917 0.047275115
    H 0.057780696 0.052527905 0.056467498 0.072882469

    > ## lower limit

    > t(xtabs(lo ~ x1 + x2, data=dfr))
    x2 a b c d
    A 0.003074706 0.003999826 0.007446270 0.005444159
    B 0.008990184 0.013772446 0.011091663 0.006939026
    C 0.008990184 0.018155074 0.016500085 0.017050341
    D 0.019821940 0.018155074 0.025449311 0.024316089
    E 0.024882259 0.022623136 0.022060769 0.025449311
    F 0.027725838 0.036362876 0.031163250 0.027155504
    G 0.031163250 0.035782830 0.036362876 0.037524567
    H 0.046885949 0.042191125 0.045709812 0.060510273

    > ## upper limit
    > t(xtabs(lo ~ x1 + x2, data=dfr))
    x2 a b c d
    A 0.003074706 0.003999826 0.007446270 0.005444159
    B 0.008990184 0.013772446 0.011091663 0.006939026
    C 0.008990184 0.018155074 0.016500085 0.017050341
    D 0.019821940 0.018155074 0.025449311 0.024316089
    E 0.024882259 0.022623136 0.022060769 0.025449311
    F 0.027725838 0.036362876 0.031163250 0.027155504
    G 0.031163250 0.035782830 0.036362876 0.037524567
    H 0.046885949 0.042191125 0.045709812 0.060510273

  • Matthias Kohl added an answer in R:
    Has anyone run PK simulation solely using R?

    is it possible?

    Matthias Kohl

    R package PKfit looks promissing; see http://pkpd.kmu.edu.tw/pkfit/



  • Ahmad Usman added an answer in MATLAB:
    How can i verified my microring resonator design with theoritical?

    how can i verified my microring resonator design with theoritical other than using matlab? 

    Ahmad Usman

    May I ask what frequencies and materials you are using for your design ?

    For optical frequencies, you can use COMSOL or LUMERICAL softwares to verify your design. 

    For microwave frequencies you can use HFSS as well to estimate S11 and S21 parameters.

  • Erik Baxter asked a question in Infinity:
    Is it true that no non-trivial solutions to Einstein-Yang-Mills equations in asymptotically flat space possess a global magnetic charge?

    This is less a question, more a request for confirmation of my understanding of some reading I've done. Is the following true?

    For asymptotically flat solitons (generalisations of Bartnik and McKinnon's su(2) solutions), it appears that the asymptotic values of the gauge fields (i.e. for r tending to infinity) are fixed to certain integer values, which means that the tangential pressure P vanishes at infinity. This in turn means the solutions carry no global magnetic charge, for if they did, the Einstein equations would be singular at infinity.

    If anyone could either confirm this, or else point out my error(s), I'd much appreciate it.

  • Peter Oluwole Ajewole added an answer in Nano:
    Determination of nano particles size

    Where can I get particle size analyzer or TEM in Nigeria for analyzing nano particles?

    Peter Oluwole Ajewole
    You can try EMDI at Akure, Ondo State or PEDI in Ilesa, Osun State
  • Nick Sakich asked a question in Animal Feed:
    Is this animal behaviour study potentially publishable? Tips on how to make it so?

    Some of my peers and I are conducting a study of the preference (or lack thereof) of experimental animals for feeding on larger or smaller food items in what is intended to be a test of Optimal Foraging Theory. As far as I know it has never been done with this species. We've whittled down our sample size to animals that are willing to eat our food items of choice (n=12), and we plan on doing 3 different variations of the experiment. Is this potentially publishable, or is the experiment too simplistic? Does anyone have any tips on how to make it more likely to be publishable?

  • Henry J Kaminski added an answer in Parkinson's Disease:
    We have observed that a freqüent myasthenia onset in Parkinson disease is a head dropped syndrome. Do you think that it is due to cervical rigidity ?

    More than expected head dropped myasthenia onset are patient with Parkinson disease (25%) and majority of myasthenia onset in patient with Parkinson disease is head dropped (more tan 60%). We think that it may be due to fatigability associated to cervical rigidity. What do you think?

    Henry J Kaminski

    I agree with comments above.  You need to look for a paraspinous myopathy.  The etiology of which is not known but may be related to hyperextension injury of neck muscles, which could occur with increased weakness from MG or altered posture from PD.  From a therapy perspective you need to assess if this is MG or not.

  • Henk Smid added an answer in Gravitational Waves:
    Can the non-existence of gravitational waves refute General Relativity?

    On the one hand, the search for gravitational waves was not fruitful for 100 years.On the other hand, General Relativity is a well-corroborated and respectable theory

    Henk Smid

    Dear Remi,

    There is a huge difference between a change in orbital motion (a dynamical effect) and the system (possibly) observed by LIGO (a cataclysm where the effect is the loss of mass on the order of the solar mass). The former might be plenty in our neighborhood but so weak they cannot be observed, the latter is probably rare but gets this big factor due to the old E=mc^2.

    One could think a relatively close super-nova is also cataclysmic but then the collapse is mostly spherically symmetric and gravitational radiation is in the higher multipoles (I think).

    Met hartelijke groeten,   Henk Smid

  • Phil Barbonis added an answer in Service Design:
    I'm looking for a model that contains all the components of a service delivery process. Any suggestions?

    From my point of view, a service delivery process has as inputs: consumables (inputs used and consumed), information, technical resources, human resources, procedures, customers; and as output: those for the customer and those for the service provider. Does something like that exists in literature? Thank you

    Phil Barbonis

    Signor Barravecchia,

    It is unclear what you intend to do with such models. Models can have as many or as few components as the author wishes, and it can be simple  as input --> process --> output,  to as complicated as one wishes with many blocks, tiers as one wants to represent. If you include the customer as well, then you have to have the service-providing agent as well at the moment when the employee and customer encounter each other, in your model.  In service encounters, the issue of emotion often engendered in experience of service by the customer could perhaps be considered**. What about elements of location,  and of layout? I presume under the technical resources label, you also include technology. The issue of cost, of productivity could perhaps also be incorporated in your model. A recent paper which recognizes that suppliers of products bundle it with services,  could perhaps be of help to you:

    Resta, B., Powell, D., Gairardelli, P. & Dotti, S. (2015): Towards a framework for lean operations in product-oriented service systems. CIRP J of Manufacturing Science and Technology, 9, May 2015, 12-22.

    **  D Hartsuiker & P Barbonis (2009):  “Experiences” as the Principal Economic Offering in     Service Delivery Systems:   Is the PAD Paradigm an Appropriate Aid to their Design?    POM  2009 – 2010  Annual Conference of the  Production and Operations Management     Society, Orlando, Florida, USA, May 2009 Proceedings.

  • Jody D Berry added an answer in FDA:
    Does anybody knows where I can find a list of all monoclonal antibodies approved by FDA updated until 2015?

    I'm writing a chapter and I need a recent list that contains all monoclonal antibodies and its applications and it is being very hard to find. If anybody could help me I'd appreciate it. Thanks!!

    Jody D Berry

    Contact Jan Reichert Sr Editor and Founder of mAbs journal. She seems to have an inside track on what approved and whats coming.

  • Vladislavs Sokalskis asked a question in Beta Blockers:
    Do you enter the doses of all medications in a clinical trial that doesn't aim to test drugs?

    Dear all,

    I would like to know your experience about filling out medications and the corresponding doses when you conduct a clinical trial that primarily doesn't aim to examine the effect of drugs. However, the drugs might affect the final results. When I see the publications of different clinical trials (particularly, in cardiology), usually they just mention the substance group (ACE-inhibitors, statins, etc.) without further giving information about the dosage or particular substance names.

    Therefore, the question is - whether you just fill out the substance group of current medications that patient takes (e.g. beta blockers, ACE-inhibitors, statins) or you write down, for example, metoprolol, ramipril, atorvastatin? What about dosages - how do you note, for example, the dosage of Ivabradin 5mg that needs to be taken twice a day? Do you write down the cumulative daily cumulative dosis (10 mg) or the dosis that needs to be taken each time (5 mg)?

    Thank you very much in advance!!

  • Kanaga Gnana added an answer in Groundwater Pollution:
    Is it possible to remove the contaminated oil from ground water used for agriculture and drinking?

    People living in Jaffna are facing a grave threat in accessing clean drinking water due to groundwater pollution caused by oil leakage. In recent days, oil waste is clearly observed in drinking-water sources (wells etc) in Chunnagam and Valigamam areas. Wells are the prime and mostly the sole source of water in Jaffna and this contamination is severely affecting the livelihood in those areas.
    This issue has resulted in scarcity for clean drinking water for the people living in the areas. No satisfactory action has been taken yet by authorities. Hence, there is an imminent need to create awareness of the issue to a wider audience in order to accelerate the phase at which actions are taken to solve the issue.
    Can any body give a sustainable solution fore this burning issue in Northern Sri Lanka?

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: A preliminary study survey to find the contamination was done by National Water Supply and Drainage Board, Jaffna. This analysis was done in 150 wells. 70% are in domestic used and 30% are agricultural used. 81% of wells within 200m have oil and grease contamination of more than 1mg/l and 74% of well in the distance of 200-500m have oil and grease concentration more than 1mg/l. 50% of wells more than 500m have oil and grease concentration more than 1mg/l. The pattern of oil spread is more towards North. But the area affected is around 2km diameter in distance. When the water pumped out more, the oil concentration observed is also more. The analysis of heavy metal yield that 10% of the wells have contamination of Pb above normal limit and 12% of wells have chromium above normal limit.
      Full-text · Conference Paper · Feb 2015
    Kanaga Gnana

    The oil in the well water can be decreased in 6 months by physical, chemical and biological processes. If someone is reporting a result obtained 6 months ago may have changed now. Physical: evaporation by heat and wind; chemical: by excess nitrate and other oxidizing agents.  Nitrates in the water are useful in this action; (In many places nitrates are pumped into the water to remove dissolved hydrocarbons); Biological: many bacteria consume hydrocarbon as their food. Possibly oil was present originally and no wonder they decreased by physical, chemical and biological degradation. This natural degradation process will continue, without waiting for the, administrators and politicians settle their issues.This will take much time. Ues of items like Biosanitizer will be the best way to keep the water  clean of all pollutants. If one could arrange with Northern Provincial Council experts in this field could be brought from India to solve the issue. http://www.wastetohealth.com/biosanitizer_ecotechnology.html -To prevent further addition of waste oil into the well waters all patches of oil found around the power plant must be treated and cleared.

    Ecorestoration of ponds, lakes & rivers - http://www.wastetohealth.com/ecorestoration_presentation.html

    It is good to look at the data collected from the Ground radar and check for any further damage done to the ground near the power station.   Now that Chunnakam has got a new power plant with better Environmental Management must arrange with CEB to Terminate the contract for having polluted the ground water and claim damages for all the damage caused so far when the court case in Mallakam results also become available.

    BIOSANITIZER Mechanism:  

    BIOSANITIZER Ecotechnology involves using the BIOSANITIZER bio-catalyst granules in fluids (liquids and gases) and using the remediated fluid as a resource for healing the ecosystem.
    BIOSANITIZER granules convert polluted water into clean water, which also becomes a resource for eco-logical restoration of wells, borewells, water storage tanks, ponds and lakes. This action can be summarized as follows:

    Pollution problems arise due to nitrates. Hence nitrate management is crucial. Low-nitrate systems develop self-healing ability.  Inorganic as well as toxic organic pollutants get converted into resources, in low-nitrate systems.
    Conventional denitrification technique consumes organic food and oxygen, to produce CO2 and waste heat. Nature prefers another reaction, i.e., combining nitrates, CO2 and waste heat to produce organics and oxygen. Green plants and also the BIOSANITIZER use this reaction. It is a resource-generating mechanism, while conventional denitrification is a wasteful reaction. Hence there are alarms associated with the conventional denitrification process.
    BIOSANITIZER is a natural catalyst; 100 mg of this product has the capacity of 1 acre of rich natural forest, in terms of its nitrate utilization, CO2 trapping and oxygen production ability.
    By adding BIOSANITIZER in a stream or a reservoir of polluted water, we get not only clean water, but the treated water has a potential to clean the whole ecosystem, without producing any other waste stream and without producing greenhouse gases. In fact, the treated water starts absorbing the CO2 and NOx from the air, thus helping ease the pollution that has increased by about 25% after we started using the fossil fuels.
    Methodology that was used to develop the BIOSANITIZER and also to crack its mechanism can be learnt through the ’Methodology Articles’ at http://www.wastetohealth.com/methodology_articles.html. The following digital scale was also useful in analyzing the natural events. Mild (1st digit) pollution is converted into ‘visible’ indicators.  A 2nd digit pollution sounds audible alarms, 3rd digit pollution is indicated to our skin, 4th digit pollution warns us through creation of odor or through short-term illness and 5th digit pollution causes premature death

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  • Ebrahim Sangsefidi added an answer in Mechanical Testing:
    Hi Does anybody have any idea, why Atterberg Limit Test is done on aggregate pass No.40 sieve? Cheers

    If the answer is that finer fraction of material will show plasticity behaviour so why does not this test accomplish on materials finer than No.200 sieve, for example?

    Ebrahim Sangsefidi

    Dear Emad,

    Thank you for your response to this question.

    I mean why the No.40 sieve? For example, why we do not use No.100 or No.20 sieve? Take into consideration that I know the result of PL and LL will change because of changing the size of aggregate.


  • Mehmet Ali Tibatan added an answer in Biotechnology:
    How I select ONIOM layer?

    I am working with DIM(3,3'-Diindolylmethane ) and optimize it by using gaussian09.Now,I want to ONIOM analysis but I don't understand which part I select as high and low layer  for 2 layer ONIOM analysis as well as medium layer also for 3 layer ONIOM analysis.

    I also added my file.Plz needed kind response.

    Thanks in advance.

    Mehmet Ali Tibatan


    I don't know did you check the gaussian web site?

    For a protein;

    In 3 layer active site is High layer, side chains+active side+ C(alpha) is medium layer
    In 2 layer active site is High layer+side chains
    This example is from an protein but I can't be sure whether this example can be a guide for your compound. Please check the link below if you haven't check yet.
    I hope it will work inşaAllah.

  • Erkki J. Brändas 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.

    Erkki J. Brändas


    Do you have some insight that tells you that calcium waves or hydro-ionic waves do generate feelings?

  • Luiz C. L. Botelho added an answer in General Relativity:
    How Ricci Flow is related to General Relativity?

    General Relativity tells us about curvature of spacetime while Ricci Flow is a "heat equation of the metric". How related this two equations?

    Luiz C. L. Botelho

    Good Question! .

    On Euclidean space time , the Ricci Flow equation is a NON CONSTRAINED parabolic diffusive equation .And the Einstein equation A CONSTRAINED elliptic equation .So very different mathematical objects at least on theirs time infinite asymptotic behavior .Here a question :and about considering a Ricci wave DAMPED  propagation on the Manifold (second order derivative plus a damping term -first derivative on time ) .Noe Mr Abanto , you can ask about their time infinite asymptotic behaviors .A more interesting (and very difficult question ) is ORIGINALLY studied on my book Lecture Notes : Applied Differential equations of Mathematical Physics Luiz C L Botelho World Scientific -appendix A Normalized Ricci Fluxes in Closed Riemann Surfaces and The Dirac Operator in the presence of an abelian gauge connection -pp320.

  • David Charles Wright-Carr added an answer in Local Knowledge:
    How cultural knowledges are constructed in a global society?

    Does some one know sociologists and anthropologists who have dealt with the problem of how knowledge is constructed, and particularly cultural (traditional, local) knowledge in indigenous communities? I´m looking a good theoretic background that allowed me to understand knowledge as a social construction.


    Pd: Add you answers in english, spanish or french!! 

    David Charles Wright-Carr

    On the emergence of global society and its relation with regional cultures, see:

    Wolf, Eric R., Europe and the people without history, 2nd. ed., Berkeley/Los Angeles/London, University of California Press, 1997.

    Conceptual (and visual) metaphors may be shared across linguistic boundaries, as calques. This was frequently the case in ancient and colonial Mesoamerica. I have written a bit on this topic, comparing metaphors shared by the Otomi and the Nahua:


    For a critique of Whorfian linguistic determinism, please see this article:


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Language and other elements that constitute culture should be treated as independent variables when trying to understand late pre-Hispanic and early colonial central Mexican society. At the time of the Spanish conquest, native kingdoms in this region were inhabited by speakers of several languages belonging to diverse linguistic families. The majority languages were Nahuatl and Otomi. A comparative study of the words used in these languages to express concepts from several semantic fields reveals an abundance of calques, or semantic loans devoid of phonological correspondence. In this study, which draws on fifteen years of research on central Mexican culture, language, and writing, examples of calques will be presented from six semantic fields: toponyms, anthroponyms, names of deities, calendrical terms, social structures, and metaphorical couplets. This research reveals a high degree of cultural unity between these two language groups, forcing us to rethink the relationships between language, culture, and ethnicity. The abundance of calques between these and other native languages is the cultural basis for the fundamentally semasiographic system of pictorial writing used throughout much of Mesoamerica; most of the graphic signs in this system of notation can be read in any of the languages spoken by groups that participated in Mesoamerican culture.
      Full-text · Chapter · Nov 2015

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  • Nicholas Legendre asked a question in Muscle Derived Stem Cells:
    Is this normal Dyecycle Violet Staining?

    I'm having issues with my Dyecycle Violet Staining (DCV).  I isolated primary adult mouse muscle stem cells (These cells have an endogenous GFP reporter).  I stained for some markers as well as did DCV staining. However, my results don't look like what is shown in the link.

    Does anyone have experience w/DCV staining? Are my results normal?  I've attached them as a PDF.   

    + 1 more attachment

  • Denis Samarin added an answer in Psychological Disorders:
    What is the distinction between moral and mental disorder?

    Do moral disorders lead to mental psychological disorders in individuals?  

    Denis Samarin

    Apparently, you mean the name of the now-forgotten German psychiatric diagnosis: a misanthrope. This name means "the man without a soul",  the moral ugly creature, capable of the most wild action without any mental agony. These people have no mental disorders, they live in harmony with itself. They simply are not people. The number of such people has increased greatly, and their credo - "nothing personal, just business."

  • Zulfiqar H Khan added an answer in Thermal Expansion Coefficients:
    What are the origin/ underlying causes of negative thermal expansion coefficient of Graphene? Why does it increases as it cools down?

    Graphene has negative thermal expansion coefficient (TEC) i.e. it increases when temperature decreases unlike all metals which show positive TEC. Why does graphene and metal/insulators like SiC or Si have difference in the sign of  thermal expansion coefficient (TEC)?

    Zulfiqar H Khan

    Many many thanks to Malur. Thanks a lot Ruoff and Zacharias. Now,I can understand better.

  • Khalid El BAIRI added an answer in TF-IDF:
    Why doesn't PubMed apply more advanced retrieval model?

    They use Boolean model. Why not TF-IDF or probabilistic model?

    Khalid El BAIRI

    Interesting question, 

    Documents may be somewhat relevant if it matches some of the queried terms and will be returned as a result, whereas in the Standard Boolean model it wasn't.

    Extended Boolean model is a  necessity not only for Pubmed but also for the advanced databases such Web of science and Scopus.

    I hope that will be true as soon as possible

  • Eduardo Antonio Molinari-Novoa added an answer in Orchids:
    Somebody could share the plate & description of Maxillaria ecuadorensis from Dodson, C.H. & P.M. Dodson. 1980. Orchids of Ecuador. Icon. Pl. Trop. 4?

    I specifically need the written part (description, synonymy, comments, etc.), but having the plate would be fine.

    Eduardo Antonio Molinari-Novoa

    Excelente, ¡muchas gracias!

  • Anton Schober added an answer in Complexity:
    Are there 2-D extension of real number like complex numbers that is non-commutative?

    Quaterion is non-commutative but it is a 4-D type hypercomplex number. We also have Dual Numbers and Hyperbolic or Perplex Numbers but they are still commutative. Are there other 2-D hypercomplex numbers similar to complex number but non-Abelian?   

    Anton Schober

    Kara> I don't "insist". sigma(z) and b(12) = 1 generates this group. The group acts on R2, but it is not a "classical group". b(12) generates the translations in x direction and the sigma(z) group has hyperbolas as orbits. very funny, it is a subgroup of the affine group of the plane.

  • Youssef Khmou added an answer in Gravitational Waves:
    What type of a wave: the gravitational wave?

    Gravitational wave has now becomes a reality. It is analogous to the electromagnetic wave that is emitted by an accelerating charged object. What type of wave is it? A tensor, a vector or a scalar wave? With what speed does it travels? It composes of what fields and their relation to each other? How a tensor wave travels? Does it arise from dipole or quadruple radiation? Any other physical properties does it carry?