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  • Peter Carl added an answer in Meteorology:
    Is global climate change due to human influence?

    The trend of the anomaly of global land surface temperature (GLST) had been numerically simulated perfectly by me with a group of simple periodic mathematics functions, which is obtained  with a numerical-functional-analysis-modelling technique in a computer. The result means the modern climate change may be not dominated by human influences due to  the function which perfectly fits the actuate anomaly of GLST from 1880 to 2013, is periodic rather than an irreversible function.

      Do you agree my view?

    Peter Carl · ASWEX - Applied Water Research

    Hi Tan,

    I prefer to read about facts in place of emotions and/or ideology here. Therefore: can you a bit better specify your data and results, please: How many data points did you use (i.e. what is the temporal resolution of your time series?) and how many component functions do you need to approximate your time series (at what accuracy?). Did you try to develop an insolation scenario over the timespan of your climate projection? The sun is an anthropogenically undisturbed system - okay? Can you predict the behaviour of the sun (top-of-the-atmosphere insolation)? Not only according to your reasoning: this would be a great achievement. You might try to 'predict' (insolation as well as temperature) into the past, beyond 1880 and show how good your time series decomposition works. At least for land surface temperature, the extra effort should be minimal. Did you do such a test?



  • How can I acquire mitochondrial DNA-depleted Rho0 cells?

    How do you acquire mitochondrial DNA-depleted Rho0 cells? I exposed cells to 50 ng/mL EB for generation of Rho0 cells, but nothing abnormal has happened compared to non-treated cells.

    Could anybody tell me some specific details about the whole process?

    Dominique Liger · Université Paris-Sud 11

    Hi there,

    50ng per mL seems low to me for EtBr treatment... I remember using 10µg/mL. EtBr is specifically targeting mitochondrial DNA and prevent its replication to generate rho0 cells. This step is made in rich medium containing glucose so as you said there is not much visible as yeast is able to efficiently grow on glucose with or without functional mitochondria (yeast is able of both respiration and fermentation on glucose). To be sure you have generated rho0 cells you have to plate them on YEPD to isolate colonies and then test these on YEPglycerol : rho0 cells won't grow on glycerol. You can also test DAPI staining to check the absence of mitochondria .

  • What are the most important issues in drilling by aphron based drilling fluids?

    I want to work on aphron based drilling fluids during my PHD. Now I am reviewing the published literature but it would be great to have the opinion of an expert in this area.

    Mohammad Ali Danesh · OPEC / Research Division

    Aphron fluid technology has enabled the redesign of wells in mature fields driving improved field economics into the picture.  Aphron fluid technologies have mitigated the issues associated within these challenging mature environments, enabling the use of full density fluids, optimizing the working environment and eliminating the need for an intermediate string of pipe. 

  • Nassim Abbas asked a question in DST:
    How to resolve the computational complexity of the DSmT when the number of information sources is large ?

    The Dezert-Smarandache Theory (DSmT) of plausible and paradoxical reasoning is a natural extension of the classical Dempster-Shafer Theory (DST) but includes fundamental differences with the DST. DSmT allows to formally combine any types of independent sources of information represented in term of belief functions, but is mainly focused on the fusion of uncertain, highly conflicting and imprecise quantitative or qualitative sources of evidence. DSmT is able to solve complex, static or dynamic fusion problems beyond the limits of the DST framework, specially when conflicts between sources become large and when the refinement of the frame of the problem under consideration becomes inaccessible because of vague, relative and imprecise nature of elements of it.

  • Eraldo Banovac added an answer in Reality:
    Do great scientists communicate with the real world successfully?

    Many scientists are truly occupied with their researches, experiments and studies. Considering often remarkable ideas in depth, some of them have built their own realities. Hence, are they capable of communicating with society successfully?   

    Eraldo Banovac · Croatian Energy Regulatory Agency

    Albert Einstein and Charlie Chaplin

    Einstein: "What I admire most about your art, is its universality. You do not say a word, and yet ... the world understands you."

    Chaplin "It's true. But your fame is even greater. The world admires you, when nobody understands you."

  • Ierardi Enzo added an answer in Celiac Disease:
    Does anybody have experience or knowledge about the association between celiac disease and "in toto" or selective deficiency of immunoglobulins?
    We experienced this association recently, and noted very interesting and peculiar aspects of the disorder.
    Ierardi Enzo · Università degli Studi di Bari Aldo Moro

    Of interst for the question.

  • What anesthesia technique is used in your center for kidney transplantation and why was it chosen?

    I see many anesthesia technique can be used for kidney transplantation.

    In my hospital we use combined thoracal epidural anesthesia and intravenous anesthesia using TCI propofol.

    Velupandian Guruswamy · Leeds Teaching Hospitals NHS Trust

    I do paediatric renal and liver transplant. For paediatric renal transplant recipent , I give my patients a GA with remifentanil , oxygen,air sevoflurane anaesthesia and mostly morphine PCA or opioid infusion . Very occasionally epidural .

    I have written a CPD article in BJA which should be published soon.

  • Can I explore the association between two continuous variables using simple regression?

    Is it fine to explore the association by applying simple linear regression as I could visualize the positive association on regression line using scatter-plot? Also, this analysis would help me to treat one variable as a predictor and another as an outcome variable, it would also help to demonstrate how much variance is explained in the latter by the former. I have rarely encountered this way of analyzing the relationship between two variables, most scholars employ correlation analysis.

    Emilio José Chaves · University of Nariño

    Biba: Some non-linear datasets may be worked fine with numerical methods recipes.

    I can work ordinal data -as Likert´s- treating it as continuous. If you may send a sample of 20 values (X1; X2) obtained randomly from your dataset, it is possible to get a nonlinear solution using Excel. Explaining it takes longer than doing it.

    OK. Send the database and let´s see what happends. emilio

  • Michael W. Marek added an answer in Research Papers:
    Can we define an expiration date or useful age for our papers?
    Is it reasonable to use these terms?
    A number of papers have been published a long time ago, but still have many citations.
    If it is possible, then is it predictable?
    Is citation can be a suitable measure to judge the useful age of a paper?
    Which papers have more useful lifetime or long expire date?

    Thanks for your inputs.
    Michael W. Marek · Wayne State College

    A given paper may be worth citing for many years, particularly if it contains something that breaks new ground in a subject.

    But in constructing a literature review for a new paper, reviewers will want you to cite recent work in your field.  When I perform peer review on a paper, I look for roughly half or more of the citations to be within the past five years.  This way you demonstrate that you based your research on the most recent work in the field, not on older ideas.

  • Eraldo Banovac added an answer in Energy Resources:
    Can science provide solutions for the main problems of the world?

    Nowadays, there are some high priority problems at a global level, such as: poverty, limited energy resources, limited food and even drinking water (especially related to the population growth phenomenon), global warming and rapid climate changes, the gap between developed and undeveloped countries. 

    Eraldo Banovac · Croatian Energy Regulatory Agency

    Dear RG friends,

    Season's Greetings and best wishes for 2015. 

  • John F. Wilhite added an answer in Ancient History:
    Accounts attributing to divine sources our codes for interpersonal conduct?

    I'm seeking additional examples to go along with those like (a) the Babylonian king Hammurabi receiving his ‘code’ from Shamash (the god of justice) or (b) the God of the Israelites presenting Moses with the Ten Commandments on Mount Sinai. What are some other historical myths of divinely bequeathed moral codes?

    John F. Wilhite · University of Tennessee

    Jim, since you're making a comparative study you may want to look at the Popol-Vuh, the bible of the Maya.  It's creation, law-giving, wages of sin stories are very interesting with parallels to the Christian Bible.  Adam and Eve were punished for gaining forbidden knowledge.  The early Maya had as much knowledge as the gods so in their next incarnation they were "dumbed down" so that the gods would be praised for being "special," the creators of man (created from corn, by the way).

    One man's mythology is another man's theology.   

  • P A Azeez added an answer in Online Education:
    Do you agree with Daphene Koller's view on what we are learning through on-line education?

    On line education is the in thing and is going to alter the way we learn and form our world view. Do you agree with this. Here is an interesting view put forth by Daphene Koller.

    P A Azeez · Salim Ali Centre for Ornithology and Natural History

    I agree with Dr Bhanot; We need to make use of all available avenues to educate to spread the knowledge; Essentially a process of opening up the knowledge-base

    Of course, any type of  education process has the issue of imposing a culture, values etc of the educator on to the audience/ educated and that is necessary evil. 

  • Andrii Tarieiev added an answer in Teucrium:
    Is this Teucrium polium or Teucrium popovii?

    Teucrium polium L. (Lamiaceae) is a polymorphic species, but I found this sample of plant very close also to Teucrium popovii R.A.King, it is found near Taif, Saudi Arabia..unfortunatelly I don't have the full botanical description of Teucrium popovii. Please help me in the identification of this species and provide me any text in matter.

    Andrii Tarieiev · Georg-August-Universität Göttingen

    I'm afarid that pictures are not fully suitable for exact identification, but you can see the holotype specimen of T.popovii:
    Full description of T. popovii you can find here
    As for T. polium, this species is cosmopolitic, therefore so variable in morphotype.
    I hope this will be helpful for you.

  • Louis Brassard added an answer in Modern Philosophy:
    Do you believe that for Galileo "secondary qualities" are restricted to the mind of the perceiver?

    Hume stated that the main principle of Modern science and philosophy “is the opinion concerning colors, sounds, tastes, smells, heat and cold; which it asserts to be nothing but impressions of the mind, derived from the operation of external objects, and without a resemblance to the qualities of the objects”. In this formulation, the mind appears as being a non-physical system that adds subjective “secondary” qualities (impressions) to external objects in the process of perception.

    This kind of formulation had led to the famous Cartesian mind-body dualism (the theory that the conscious being is composed of two independent substances, the body and the thinking mind) and the related mind-body problem (how could an immaterial soul interact with the material body?), for which an acceptable solution (Descartes’ appeal to the pineal gland not withstanding) was not found yet and will probably never be, because of the way the issue was formulated.

    A recent study (Buyse, 2013) has shown that Galileo, considered to be the original author of the distinction of primary and secondary qualities in Modern times, was not a mind-body dualist and possibly made a formulation of the problem that is different from Descartes and Hume, one that may inspire contemporary researchers to find a solution. Buyse writes: "The sky is not blue and roses are not fragrant. I just experience them to be so, or they appear to me – affect me – as being like that. The real, objective world is therefore the world of the primary properties, while the realm of subjective secondary qualities is the domain of animals and human beings", and quotes Galileo:" ‘I think that if one takes away ears, tongues, and roses, there indeed remain the shapes, numbers, and motions, but not the odors, tastes, or sounds; outside the living animal these are nothing but names’" (Buyse, 2013).

    Buyse also discovered a frequent mistake in the translation of Galileo’s Italian originals: "In most cases, Galileo’s text is translated as meaning that secondary qualities exist only in the (immaterial) conscious mind of the observer, however: In the original text, Galileo nowhere writes that secondary qualities and emotions reside ‘in consciousness’. On the contrary, he writes that "they reside ‘in the sensible body’ [nel corpo sensitivo], or in other words, in the body of the perceiver, whether it be a human body or an animal body" (Buyse, 2013).

    As far as secondary qualities are instantiated in the body of animals, and living systems are considered to be physical systems, there must be a physics of the conscious mind. Galileo would probably agree with this challenge.


    Buyse F. (2013) The Distinction between Primary Properties and Secondary Qualities in Galileo Galilei’s Natural Philosophy. Talk given in September 28, 2012, at the Quebec Seminar in Early Modern Philosophy and in April 8, 2013, at the History of Science Collections in Bizell Libraries at the University of Oklahoma. Available at: https://www.academia.edu/6652802/The_distinction_between_Primary_Properties_and_Secondary_Qualities_in_Galileo_Galileis_Natural_Philosophy


    Sound is a transformation of air pressure signal. The former is a subset of the later.  The pressure signal is a high dimensional vector and the sound is a lower dimensional vector, a projection of the other one on a sub-space.  We are dealing all the time with representations meaningfull within our mathematical language.  

  • Imre Tóth added an answer in Ammonia:
    The total nitrogen measurement incorporates organic and inorganic nitrogen ?

    With the help of spectrophotometric method, i have determined total nitrogen, nitrate and ammonia value are 17,15 and 14 ppm respectively, my question is how come it is possible if  the concentration of nitrate and ammonia will be added up, then the concentration of total nitrogen would be approximately 30 ppm but i am getting only 17ppm.....

    Why is it so?

    Imre Tóth · University of Pannonia, Veszprém

    Why not check then whether your total N determination works properly with a known concentration of let's say (NH4)2SO4. For the first sight it seems that there was a trouble with your total N i. e. with the digestion and you got only NO3 for total. If that is not the case, i. e. total N is OK, you can check then the phenate method with the above sulfate mentioned solution.

  • Kwamina Ewur Banson added an answer in Persea:
    What are the effects of avocado fruit tree (Persea americana) on the soil properties?

    • Farmers are complaining about persea americana fruit trees negative side effect on their soil beside the benefit that they are earning from selling of the fruit.

    • Do you have any type of documents that explains about the effects of avocado fruit tree on the soil physico-chemical properties?

    Kwamina Ewur Banson · University of Adelaide

    Dearest Haile,

                                  Avocado trees are heavy feeders, so plenty of good compost is needed to attain reasonable yields. They respond well to organic culture, most organic growers rating them as easy to grow. Their naturally surface rooting system necessitate mulching and nearly always irrigation is required. They are prone to a variety of trace element deficiencies. Avocado tree roots are peculiar in that they require a lot of air or oxygen. When freely developing in the leaf mold under the tree, they have access to plenty of air and are most happy. When this mat of root fibers is partially shut off from the air by being covered with soil (especially heavy soil), the tree immediately shows its discomfort. Partial loss of fiber roots when soil air is replaced by free water results in decline of the top, the degree or severity of which depends on the proportion of roots lost. Total and sudden loss of fibrous feeders results in collapse or asphyxiation.Those who are familiar with the history of the avocado industry know that from the beginning subdividers and planters generally looked first for suitable climatic conditions with available water, and considered soil conditions to be of secondary importance. As a result of this, many trees were planted on soils more or less unsuited to them. In fact, it is my opinion that the major part of the present acreage is defective in drainage and aeration. It is quite beside the point to tell a grower that his tree decline is due to poor soil drainage when he has already spent his money planting trees on that soil. Of course, if he has planted in an impossible situation, the sooner he quits the better. But the great majority of growers are dealing with soils which are only partially defective. What the grower needs is a better understanding of the true soil conditions of his grove, as well as help in devising ways and means of so handling that soil as to overcome the difficulty or at least to avoid doing anything which will intensify the trouble.

  • Jacque P K Ip added an answer in FRET:
    How can I prove GEF interacts with Rac1, cdc42, and RhoA?

    I found a new GEF and I want to know which small GTPases will be activated by this GEF. I did FRET biosensor assay, I found this GEF interact with Rac1 and cdc42 but not RhoA. I did another experiment to confirm my data. I cotransfected cell with GEF and siRac1 (or siCdc42 or siRhoA). I observed an effect of localization of this GEF in cell transfected with siRac1, siCdc42 but not siRhoA. These data can tell me that this GEF actives Rac1, Cdc42, but not RhoA?

    *Other GEFs can also activate Rac1, Cdc42, RhoA

    Which assay should I do to prove Rac1 and Cdc42 are downstream of my GEF?

    Jacque P K Ip · Massachusetts Institute of Technology

    You can perform a GTP-Rac1 assay and GTP-Cdc42 assay with or without your GEF. If you see increase of Rac1 activity (as revealed by GTP-bound Rac1), then you can claim it's a GEF for Rac1. You can do the same for Cdc42. It's a pulldown assay with WB analysis. You can either purifiy the GTP-bound active domain by yourself or buy the kit available. See this link: http://www.cytoskeleton.com/bk035

  • Ján Kozempel added an answer in Deuterium:
    How can I figure out the percentage of deuterium incorporation in product?

    I am confused to figure out the results in deuterium labelled experiment. Can any one provide the information about deuterium labelled reactions. How to identity the presence of deuterium in compound and mainly percentage deuterium incorporation?

    Ján Kozempel · Czech Technical University in Prague

    Depends.. Normally MS or NMR should be the first methods of choice.. 

  • Alfredo Pereira Junior added an answer in Brain:
    Noninvasive brain-to-brain communication - What does it prove?

    EEG was used to record the information from the sender’s brain, and transcranial
    magnetic stimulation was used to deliver the message to the brains of the receivers. What does it prove?

    Alfredo Pereira Junior · São Paulo State University

    Dear Dorian, I voted positively for your answer, but my view is that the amplitude modulated waveform contains contributions from dendritic fields and the astroglial network. If one captures only action potentials (as in single cell recordings) then the amplitude modulation seems to be too small to encode a wave. When one captures scalp EEG or local field potentials, besides action potentials also dendritic fields and astroglial activity are included, forming the real brain wave.

  • Jon A Frederick asked a question in Neurofeedback:
    How do you design a protocol in BrainMaster 3.0 that allows you to alternate between inhibiting and enhancing the same frequency in the same session?

    I know you could set up the User frequency to the be the same and make it an inhibit; and I know you could set up to different events in the event wizard, but is it possible to alternate between enhancing and inhibiting the same frequency every six minutes or so, without stopping and starting a different session?

  • Dominique Liger added an answer in Inhibitors:
    Considering the Vmax:Km ratio, what is the significant of this ratio?

    if an Inhibitor is introduced and the Vmax:Km ratio is as follows;

    Reaction A: 0.054

    Reaction B: 0.877

    Reaction C: 1.982

    Now if reactions B and C are affected by inhibitors, what is the implication of the ratio 

    Dominique Liger · Université Paris-Sud 11

    Hi there,

    Vm/Km ratio is expected to decrease when enzyme is efficiently inhibited with competitive or non competitive inhibitors and is expected to remain the same when submitted to uncompetitive inhibitor. Therefore as there is an increase in the ratio for B and C compared to A (ratio without any inhibitor?), there is a problem... Have you run the all sets of experiments with the same amount of enzyme?

  • Thuy Nguyen asked a question in Trusses:
    How to input initial strain for LINK180 (truss element) in ANSYS APDL15 by GUI ?

    Can anyone show me how to input initial strain for LINK180 (truss element) in ANSYS APDL15 by GUI, because I am not familiar with writing ANSYS commands?

  • Hayder Oleiwi asked a question in Cathodic Protection:
    Could anyone give me some new ideas or issues which I can take into account through my PhD research about cathodic protection of steel in concrete?

    Dear all,

    For this research, reinforced concrete specimens with selected anode material will be taken to examine the influence of applied current on the behavior of steel and surrounding environment. experimental methods and mathematical models will be done in this PhD research. However, I am looking for new gaps or ideas in the design of cathodic protection of reinforcement in concrete that I should study in the research.

  • Is rapid change in mobile technologies good for world economy?

    The large number of countries have yet to set 3G networks still in the same country vendor are looking for 4G markets. It forces some countries to unnecessarily invest before time in my opinion. Your comments are requested.

    Abdelhakim El Ouadih · Cadi Ayyad University

    the fast telecommunications growing and changes is not necessary good for economy because operators find more difficulties to amortize their investment.

     the generation period became smaller and smaller (than 10 years for older generations) and the operators can't amortize in such period their infrastructure  especially for operators that have less generation networks (3G). 4G can be launched as license for  operators consortium to resolve partially the problem.

  • Alexandre Giannini added an answer in Xerostomia:
    What is the most effective method to screen for dry mouth (xerostomia/hyposalivation) in general dental practice?

    There is need for effective diagnostic criteria and functional tests in order to detect those individuals with oral dryness who may require oral treatment, such as alleviation of discomfort and/or prevention of disease (Lofgen et al., 2012).

    - Xerostomia Inventory schort form (SXI-D)
    - Index for symptoms of xerostomia (bother index)
    - Clinical oral dryness score for clinical signs (CODS)
    - Sialometry, the measurement of whole salivary flow rates

    Alexandre Giannini · Brazilian National Cancer Institute

    I totally agree with Vajia! Sialomtery of flow (stimulated and non-stimulated) is the simpliest, cheaper and easie test we can do in order to help our patients, anywhere in the world to test sallivary function, for me the KEY for oral health!

  • Shelley Minteer added an answer in Biotechnology:
    What are other (except platinum) non-enzymatic electrocatalysts for oxygen reduction?
    Oxygen reduction
    Shelley Minteer · University of Utah

    There are a lot of pyrolyzed porphryn and phthalocyanine complexes in the literature as well as transition metal chalcogenides

  • Eva Kahana added an answer in Social Capital:
    What is the leading measure of Social Capital and/or Social Connectedness?

    We need to include widely accepted and validated measures of social capital and social connectedness for a survey we are creating to assess resilience among veterans.  Thanks in advance for your replies.

    Eva Kahana · Case Western Reserve University

    I agree with David Morgan about the importance of conceptualizing resilience in ways that do not lead to tautological thinking.Using the stress paradigm you can distinguish resilience as a flexible coping strategy as distinct from the outcome ,that might be psychological well-being. Social capital is an increasingly appealing , but hard to measure construct. The trust component of social capital may be very important for veterans.

    Best of luck with your research.

  • Fernando Zamarron added an answer in Ionic Liquids:
    How can I identify morpholine acetate properties?

    Morpholine acetate is one of the ionic liquids I need to know about, but I couldn't find it. Is there anybody who can help me?

    Fernando Zamarron · New Mexico State University

    If you have skype and add credit, you can call this company based in Hong Kong who makes and sells it.

    • Angene International Limited
    • 4/F Silvercord Center Tower 130 Canton Rd,KL,Hong Kong
    • Tel: (852) 8191 6999

    It might be that morpholine acetate is only ionic in water.

  • How can we promote Risk Perception?
    We all work around Seismic Risk. Structural Behaviour, Retrofit Techniques, Scenario Simulation, Loss Quantification and so on. But. Do people feel at Risk? If not, how can citizens be willing to pay Seismic Risk Reduction policies and practices? Do people know about Feasible Risk Reduction Strategies and actions? If not, how can people be willing to pay Seismic Risk Reduction policies and practices. If someone has any ideas about this, please share.
    Roberto De Franco · National Research Council

    The real problem, as previously claimed by Max Wyss, is how to reach the population or better how to engage the society in the risk reduction and the connected actions. Probably the better choice to reach the claimed objective is to orient our action towards the risk acceptance.
    The risk perception not includes necessarily a responsability assumption, the acceptance yes.
    Even though the perception implies cognitive aspects of the risk, it has more psycological implications than the acceptance, which, differently in my opinion, implies a real taking in charge of a comportamental choice (social in latu sensu).
    The risk acceptance is an evaluation of the advantages / disadvantages of some actions (scientific, technical, psycological, social, economical) in order to proceed towards an operative choice finalized to the risk reduction and to the consequent taking of the social-economic risk.
    In my opinion the acceptance should include a real engagement of the public which is subject to the risk condition through different level of an information program, oriented to the cognitive and psycological risk perception (risk assessment, risk exposition, modification of the life quality), and mainly finalized to the risk acceptance (responsible decisions and actions in the risk condition)
    Probably in this condition, the public could partecipate effectively to a program of risk reduction.
    For example a scenario or a simulation, which includes also social and economical effects does not inform the citizen how his life could be modified in terms of his responsabilities and consequent actions. Basically it is useful to furnish important information to the decision/policy makers. But, how much information contained in a scenario or in a simulation are useful for a citizen in order to protect himself and to contribute to the reduction of its real risk? Or best, how the important information contained in them becames useful to enhance the responsibility of a citizen community?
    Until the risk reduction programs will be only the result of a top-down process from scientists and/or decision makers and/or legislators to social community, this community will not understand why it is important a politics for risk reduction and why it should take in charge part of the cost (social and economical) connected to its reduction before, during and after an event.
    The risk reduction is basically similar to that of a network problem with distributed users over different levels, each level of network contributes to the real risk reduction.
    The taking the social-economic risk in distributed form is a factual way to distribute the environmental-risks at each user level through its acceptance of a part of risk (technological-social-economic choices and actions).
    A trivial example: when we assure our car we are informed about our part of the assured risk and accept it and the risk taking correspond to a comportamental responsibility and action (the acceptance).