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  • José Manuel Valdés Reyes added an answer in Antioxidants:
    What is the relation between small Mafs and the keap1-Nrf2 activation of ARE?

    What we know: It's been established that keap1 is involved in the regulation of transcription factor Nrf2, facilitating its ubiquitination and degradation in basal conditions (either by sequestering in the cytoplasm or actively shuttling it out the nuclei). When oxidative stress triggers a change in this mechanism Nrf2 migrates to the nuclei, where is binds the antioxidant response element (ARE), an upstreaming promoter region of many antioxidative, drug-metabolising and cytoprotective genes. This seems to be fairly well established.

    But it gets more complicated than that: It appears that to do this Nrf2 requires dimerisation with other proteins containing bzip complexes. I had read that small Maf proteins were normally involved in this activation of ARE. However, I have recently come across a different model that suggests that Maf proteins actually inhibit expression of this genes and it is binding of Nrf2 to other bzip-containing factors that leads to upregulation (I've attached the model, from the NCI's cancer genome anatomy project, below).

    Confusing models: Most of the literature I've found supports the opposing idea of the Nrf2-Maf dimers having an upregulating effect. Are these just different models? Has one premise been proven valid over the other? Or have I simply misunderstood this? If anyone has a better grasp of this than myself any comments would be great.


    José Manuel Valdés Reyes

    Dr Le sirvió?

  • Hassan Hakimi added an answer in DNA Binding:
    What is the best way to look for a conserved motif in whole genome of an organism?

    I am looking for the proteins  that have DNA binding motif in their structure in Babesia spp. I was wondering whether there is a free software to look for that.

    Hassan Hakimi

    Thank you Indu and Esteban.

    Actually I tried MEME but I was not able to use it to look for a domain in a database such as piroplasmdb or plasmodb.

    It need to upload the sequence. I was wondering whether there is a way to directly link MEME to a database or not

  • Eva Hamilton added an answer in Atopic Dermatitis:
    Is there any insight for a curative treatment in the cause of pediatric atopic dermatitis?

    Apart from statutory moisturizers and palliative care leading to corticosteroidal suppresion or calcineurin- or Janus kinase targeted immunosupression, is there any hope on other kinase targets eg. TrkA in paper 25594427 attached, relevant to keratinocytes  or skin constituents with possibly less adverse effects? The catch usually is the chronic application setting and a reversible -take it, it stops- stop taking it, it comes back with a vengeance- feature, that would best be minimized.

    Is there any value in personalised prick/allegy screen test of an exhaustive antigen repertoire including clothing fibers, food constituents, urban pollutants, less established or suspected allergens?

    Taking another twist, eg. paper 26385242 attached, have any "Genetic variants and epigenetic alteration as tools for the molecular taxonomy of AD provided the background for personalized management" ?

    + 1 more attachment

    Eva Hamilton

    Thanks Vladimir, I now just have to become fluent in Russian!

    One more question - you suggest taking urethral,vaginal,pharyngeal and bucal swabs - which mycoplasma sp. is  involved in AtD ?

  • Roumen Nedev added an answer in Implicit Association Test:
    Does anyone know if the "D" measure in the Multifactor Trait-Implicit Association Test (MFT-IAT) is calculated in the same way than in classical IAT?

    The algorithm used in classical IAT (following Schnabel et al., 2008) is:

    1 Eliminate trials with latencies over 10,000 ms.
    2 Exclude data from participants with more than 10% of trials showing latencies less than 300 ms.
    3 Compute one ‘inclusive’ standard deviation for all trials in Blocks 3 and 6 and likewise for Blocks 4 and 7.
    4 Compute separate means for trials in each of the Blocks 3, 4, 6, and 7.
    5 Compute two mean difference scores (MeanBlock6 − MeanBlock3 and MeanBlock7 − MeanBlock4).
    6 Divide each difference score by its associated standard deviation of step 3.
    7 Resulting D measure represents the equal-weight average of the scores calculated in step 6.

    This procedure is the one recommended by Greenwald et al., 2003.

    Roumen Nedev

    In the implicit test, each significant trait is associated with a positive, or negative value, which gives an estimation, instead of a measure of the trait, as acceptable or disregarded. 

  • Farhad Dehkhoda added an answer in Protein Aggregation:
    Can EDTA induce precipitaion to his-tagged purified proteins?

    I have expressed my 70 kD protein (pI 6.7) in BL21 E.coli cells and purified it using TALON metal affinity resin (cobalt-based resin). My elution buffer is 20 mM Hepes Ph 7.6, 500 mM NaCl, 10 % glycerol, 1mM TCEP, and 150 mM imidazole. My previous experience with this protein had shown that it tends to form some sort of dimers/aggregates thus I added 1 % octyl-glucoside (OG) and 5 mM EDTA to the eluted protein that were in a buffer mentioned above. Although addition of 1% OG was borne fine, upon addition of 5 mM EDTA the solution went cloudy and after 48 hour incubation at 4 degrees there were lots of aggregates in the solution. I spun down the aggregates and tried to resuspend in 8M urea but it wasn’t successful attempt.

    I thought addition of EDTA might be beneficial through chelation of any leached cobalt ions. Is it a possibility that chelating leached cobalt ions also precipitated my protein?

    Or chelation of useful divalent ions knocked my proteins out and precipitated them?

    Farhad Dehkhoda

    Hi Vladimir, thanks for your reply. I have tried various pHs and my protein showed best solubility in pH 7.6.

  • Ramesh Sharma Poudel asked a question in Pharmacy:
    Why pharmacy profession are not well recognized/not developed in developing countries till 21 century?

    Why pharmacy profession are not well recognized/not developed in developing countries till 21 century?   

  • Zhang Runhua added an answer in Probability Theory:
    How to calculate the RR and 95% CI on different reference groups?

    I want to make a meta-ananlysis. But the arcticles I identified reported RR based on different references. Some use the lowest one, some use hightest one. I want to unify all resules using highest group as reference.

      For example: there are 4 gruops originally,

       lowest group : RR      1(REF.)

       2nd  group  :   RR      0.98(0.78-1.25)

       3rd gorup:       RR      0.82(0.75-1.29)

       hightest group:RR      0.76(0.56-1.36)

    Now ,how to calculate the RR, especially 95% CI,  of each group if the reference is hightest gorup?

    Look forward for anyone's reply!

    Zhang Runhua

    Thank you both for answering my question. I did not have the origianl data, and I just have the RR and 95% CI for each categories. Hence, I think Li's answer is more suitable to solve my question. I want to know whether the approach can use if the effect size is hazard ratio(HR) from COX model?

  • Christian Boissinotte added an answer in Questionnaire:
    Do you mind answering a short questionnaire on square roots?

    Here is a link to the questionnaire.

    Your reflection will be also appreciated.

    Christian Boissinotte

    Looks like it's not there any more.

  • Tie Duerna added an answer in Coloring Agents:
    Is the high temperature causing my prestained marker to lose color agent?

    I found that when I used wet- transfer method(tank,towbin buffer,10% methanol,0.1%SDS) ,I always lost my pertained marker in the blot.

    In semi-dry method( discontinuityTris-CAPS buffer ),the maker is very clear after transfer.

    I tried 3 kinds of conditions( below) to observer  

    • 15V, overnight,4 ℃ 
    • 30V,1h,4 ℃ 
    • 25V,1h,4 ℃ 

                                 (  volt for Japan)

    while the marker was "gone"( or very weak in the high M.W. zone).And the 3MM paper was also clear.

    The after steps of WB, confirmed that the protein in the PAGE were transfer to the membrane.

    Although it didn't influence my result,I want to ask for help to make clear  what cause the marker disappear?

    Thank you!

    Tie Duerna

    Hi! Sherezade

    Thank you for your advices!

    I change the buffer from towbin to carbonate(pH 9.9) for tank transfer yesterday, 25 V 1 h, and the marker is very clear on my blot!

    The pH may be the problem!

    Although the transfer wasn't completely on the condition of 25V,1h( the PAGE still have protein remain).I will try ON next time!

    It really help!

    Best regards!


  • Tony Maine added an answer in Dust:
    Please does anyone have any material on "auto cleaning of solar panels"?

    By cleaning,I mean removal of dust particles from the solar panels for maximum light intensity

    Tony Maine

    This a very important issue which is largely ignored in most texts. It is quite amazing how little dust you require on a panel before its efficiency drops significantly. If the panel is inclined, the dust build up at the bottom can block all the bottom solar cells from working and unless the panel has been wired appropriately, it might fail to work completely with even 5% of its surface covered. I have studied this condition quite extensively. Sadly I can't recommend a single publication about auto cleaning! Hopefully someone else will be able to find one. Cleaning a solar panel is not difficult manually, but it is not easy to do automatically and cheaply. With the panel cost of a hundred dollars US or so, the cleaning device must be a fraction of that, and perhaps require water which can be very difficult to supply in desert conditions. It is a problem that requires a solution, though!

  • Bambang Sunardi asked a question in Structural Health Monitoring:
    Could anyone recommend me some method for building health monitoring?

    Currently, I am conducting research on building health monitoring using accelerograph data. Could anyone recommend me some method for building health monitoring. Thanks

  • Refik Kanjhan 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?

    Refik Kanjhan

    Dear Josep,

    That is an interesting question. I wonder whether this is due to reduction in descending inputs to cervical Motoneuron pools, changes in intrinsic properties of cervical motoneurons (such as inability to sustain firing), or reduction in the muscle or motor units? Or all of these listed above? In general, fast twitch motor units to go with aging, but may be with disease, slow twitch or slow fatigue motor units are also lost early. To keep head posture up requires a lot of muscle strength and sustained neuromuscular activity. Do you think the reduction in neuromotor activity starts centrally or peripherally? For inspiration you may want to check my recent review on that topic.

    best wishes, Refik

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Motoneurons develop extensive dendritic trees for receiving excitatory and inhibitory synaptic inputs to perform a variety of complex motor tasks. At birth, the somatodendritic domains of mouse hypoglossal and lumbar motoneurons have dense filopodia and spines. Consistent with Vaughn’s synaptotropic hypothesis, we propose a developmental unified-hybrid model implicating filopodia in motoneuron spinogenesis/synaptogenesis and dendritic growth and branching critical for circuit formation and synaptic plasticity at embryonic/prenatal/neonatal period. Filopodia density decreases and spine density initially increases until postnatal day 15 (P15) and then decreases by P30. Spine distribution shifts towards the distal dendrites, and spines become shorter (stubby), coinciding with decreases in frequency and increases in amplitude of excitatory postsynaptic currents with maturation. In transgenic mice, either overexpressing the mutated human Cu/Zn-superoxide dismutase ( hSOD 1 G 93 A ) gene or deficient in GABAergic/glycinergic synaptic transmission (gephyrin, GAD-67, or VGAT gene knockout), hypoglossal motoneurons develop excitatory glutamatergic synaptic hyperactivity. Functional synaptic hyperactivity is associated with increased dendritic growth, branching, and increased spine and filopodia density, involving actin-based cytoskeletal and structural remodelling. Energy-dependent ionic pumps that maintain intracellular sodium/calcium homeostasis are chronically challenged by activity and selectively overwhelmed by hyperactivity which eventually causes sustained membrane depolarization leading to excitotoxicity, activating microglia to phagocytose degenerating neurons under neuropathological conditions.
      Full-text · Article · Jan 2016 · Neural Plasticity
  • Albert Ruzo Matias added an answer in Genetic Engineering:
    CRISPR/Cas9 KO homology arm under 500 bp?


    I want to KO a gene and for this I am targeting the exon 1 of the gene. To increase the frequency of non-specific KO events (gRNA has six one bp mismatches in the first 13 bp) I am designing a KO homology construct with dual selection system (puromycin, TK) markers. 

    The gene I want to knock out shares a promoter with another, essential gene, therefore I can only design a short KO homology arm, 360 bp, on 5`end. The length of the other KO homology arm is 723 bp. Does anyone have experience with homology arms shorter than 500 bp? Does the recombination work?

    Thank you,


    Albert Ruzo Matias

    Hi Jana, 

    I don't understand why you need such a short arm. Even if there is a promoter, you could still use that region as a homology arm, couldn't you? Or is it because it will be a GC-high region difficult to amplify? 

    In any case, I am sure it will work. I have gone to ~400bp in one arm (because there was a highly repetitive region a little further), and it worked. It may be less efficient, but you will have the PUTK selection to select for the correctly targeted cells. 

    Another strategy to increase specificity and not having to rely on HR would be to use a double nickase approach, or the new eSpCas9... Just a thought. 

    Good luck!

  • Shrinwantu Pal asked a question in Reducing Agents:
    What is a mild reducing agent that can operate in water or methanol but won't reduce ketones?

    I am trying to reduce an organometallic complex that has a tethered diaryl ketone functional group. Unfortunately aqueous or methanolic NaBH4 reduces the ketone functional group as well. 

    Any other suggestions would be gratefully acknowledged.

  • Alfredo Pereira Junior added an answer in God:
    What is the origin of the laws and principles of nature?

    More precisely, "what is the origin of the regularities in nature which are represented (or purported to be represented) in our various recognized or accepted laws and principles regarding nature and natural events?" (this is H.G. Callaway's formulation of the original question). Such a philosophical question should be of interest to all scientists. 

    In classical philosophy, there are two ways of answering it:

    a) Looking for an explanation outside nature. The concept of a transcendent God, the creator of nature and its order, explicitly appeared in Thomas Aquinae (the world comes from God and returns to God), Modern philosophers and scientists. It reappeared in the Contemporary epoch as a refusal of Darwinism, and/or related to some interpretations of Quantum Theory;

    b) Looking for an explanation inside nature. Nature itself, being composed of both Form and Matter (Aristotle´s Hylomorphism) produces its order, in a process that has been currently called "self-organizing". In this view, God is not the creator of Nature, but - as in Aristotle´s concept of a First Mover - an ideal of perfection projected by natural beings.

    It is clear that in spite of Aquinae´s affiliation with Aristotle, their philosophies are in opposite position in regard to the question about the origin of nature´s order. 

    Spinoza tried to conciliate both approaches, by equating God and Nature. In this case, God is not conceived as a transcendent being who creates Nature from nothingness, but as a being who is somehow immanent to Nature.

    Plato, before Aristotle, presented a combined solution, assuming both the autonomy of natural principles (Ideas) and a Demiurge who prompts the manifestation of the principles into the world of appearances.

    There is a possible third alternative, advanced by Kant in his cognitive approach to philosophical issues: to assume that laws and principles of nature are 'a priori' forms that the human mind imposes to sensory "matter". However, this alternative is actually reducible to the others. Cognitive forms should be natural or created by God (both possibilities are compatible in Spinoza's approach). For instance, the Piagetian version of Kantism assumes that these forms are biological, deriving from processes of interaction with the physical and social environment - therefore, he was committed to the self-organizing view.

    Alfredo Pereira Junior

    Dear All:

    I will not reply further, because I already wrote all I had to say and do not intend to "win" the discussions.

    I am sorry if my reply to Louis may seem to be ad hominem - this is because we have a long discussion in several RG questions and he seems to be always changing views to find new ways to disagree with me - while agreeing on the deepest issues. This is probably because I did not understand well his philosophical position.

    Making a balance of the whole discussion, I find it far richer than I could imagine in the beginning. I hope you all will continue to discuss - I have to write a book for my funding agency report on this subject (more precisely, about Triple-Aspect Monism) and this discussion has been very helpful to broaden my horizon.

  • John Poke asked a question in Journal Articles:
    The problems, challenges and approaches to engaging indigenous and rural peoples in sustainable biodiversity management?

    Need a co-management study

    Need a comanagement that highlights when the co management is not working out.

    Please post reports and journal articles

  • Eric Ariel L. Salas added an answer in Landsat:
    How to find Landsat equivalent bands in AVIRIS hyperspectral data?

    I have some AVIRIS hyperspectral imagery which covers a small area. I would like to scale this up using Landsat to cover a larger region. Is there a way I can find the Landsat equivalent bands in my data. For instance, the NIR peak in vegetation occurs in band 5 of Landsat 8 OLI imagery. How can I link this with my AVIRIS data? I essentially want to reduce my AVIRIS data (currently over 430 bands) down to the 7 most important bands that match Landsat (C,B,G,R,NIR,SWIR,SWIR2).

    Eric Ariel L. Salas

    Hi Nathan,

    You are right.   If you need to compare the two images, you have to do a little manipulation on the AVIRIS data.

    As you pointed out, you can reduce the AVIRIS data down to the 7 most important Landsat bands.   One way to do this is to use the center wavelength of the landsat bands and pick the 7 channels of the AVIRIS that match the bands.  For example: channel 24 (665nm) of Aviris = landsat band 3; channel 137 (1653nm) of Aviris = landsat band 5; and so on...These are just sample numbers, and in your case, you have to check your AVIRIS 430 bands to find the matching channels for the Landsat.  This is the easy way.

    Another method is to do the weighted average of TM corresponding channels.  In this case, you are simulating the landsat bands for the AVIRIS data.

    Please check the PDF below for more.  I hope this helps.

  • Tony Maine added an answer in Morale:
    Are ethics a grammar of human expression or an essence of human relation?

    Are ethics relationally bound, universal, or ethically relative? 

    Who decides whether something is right or wrong?

    What is the syntax of the governing certainty about the implausibility of one representational ethos over another?

    How do we conceptually calibrate the reorganization of society ethically, if we do not have answers on basic morality?

    What institutions recondition our moral compass when we have through the agency of our own moral experiments fail?  Do these institutional roles succeed because of our reforming our behaviours, or through our being coerced into submission?

    Is there a time for force if so who decides how much force is appropriate?

    Tony Maine

    It is an interesting point that questions on RG relating to technical, eg engineering and scientific matters can usually be phrased quite economically, and answered in similar vein. On the other hand, questions on RG  relating to philosophical matters tend to be at least twice as long and, sadly, not thoroughly answerable with much less than a well written paper, or even a book. It would be interesting to explore this difference in its own right!

    But to get to the question you have posed, Peter, I think that part of the answer would lie in a more careful definition of 'ethics'. In  my view, ethics is a system innate to intelligent beings which govern their behaviour so that societies of such beings are stabilised against internal destructive tendencies. In this view, which is after all only a view, ethics are more an essence of human relationships than a grammar. On the other hand, ethics most certainly informs the creation of such grammars. In societies where formal speech is yet to evolve eg other primates, it is useless having an innate inhibition on violence if there is no effective body language to express this inhibition and operationalise it, so that harm does not actually occur.

    I would be interested in seeing other contributor's comments on this.

    Best wishes.

  • Ramesh Sharma Poudel added an answer in Epidata:
    How can I define data when I have multiple response using EpiData software?

    Is there any similar features with Epi Info or Something different?

    Ramesh Sharma Poudel

    Dear Yalemzewod,

    You need to make individual variables of multiple responses in Epidata software. eg Risk factors of stroke(RFS) are multiple responces:

    RFS 1Hypertension: Yes/No

    RFS 2 Diabetes: Yes/No

    RFS 3 Atrial fibrillation: Yes/No

    RSF 4 Smoking : Yes/No  

  • Nayar Gutierrez asked a question in Physical Modeling:
    How valid is to represent a shell plate with frame elements?

    I used used a frame structure to represent a continuos shell plate and this frame structure was calibrated with a physical model in order to  have the same rigidity as the real one. However I was trying to identify how representative would if a change the thick of the frame elements to represent a shell plate.

    Thank you in advance.

  • Huda Almaarofi added an answer in Civil Engineering:
    What are the main problems in arid regions hydrology?

    Let's try to make an updated challenges list for arid regions hydrology

    Huda Almaarofi

    Dear Ayad, Have a look of the attached papers, you may find them interesting

    + 1 more attachment

  • Panchatcharam Mariappan added an answer in Matrices:
    What is a nontrivial unit of 2×2 matrix nil-clean ring?

    An element a of a ring R is nil-clean provided that there exists an idempotent element e ∈ Id(R) and a nilpotent b ∈ Nil(R) such that a = b + e, a ring is called nil-clean if each element a ∈ R is nil-clean. I would like to have some examples of nontrivial unit (invertible) 2×2 matrices nil-clean (over real numbers).

    Panchatcharam Mariappan

    Dear Hanifa and Cenap,

    Sorry. I forgot that it should satisfy the closure condition. Let me argue in a different way. If there are some errors, let me know.

    Suppose a ∈ R be a nontrivial unit, then a = b + e, where b is nilpotent and e is idempotent. Since e is idempotent and 2x2. There are two possibilities (1) e is diagonal with 1 or 0 (2) trace(e)=1. Since b is nilpotent trace(b)=0. Also trace(a)=trace(b)+trace(e). Therefore, trace(a)=1. Therefore eigenvalues sum is 1. But a unit is nil clean iff it is unipotent. So, a is unipotent. a is unipotent iff its characteristic polynomial is a power of t-1 or equivalently all its eigen values are 1. Since trace(a)=1, the characteristic polynomial is t^2-t+1 and hence the eigen value of a is complex, which is a contradiction. So, I claim that there won't be any nontrivial unit. If any flaws in the proof, please post it.

  • Jeffrey Holcomb added an answer in Artificial Intelligence:
    How can I convert a raster curve to a vector curve?

    I want to calculate the length of a fiber in a raster image as accurately as possible. Maybe using a vector curve I will get it.

    Jeffrey Holcomb

    That makes the problem sound a lot more challenging.  Your biggest issue will be the clumps, not the branched and curvy.  Branched and curvy can be problematic too, but the problem with clumps is that it will be a lot more difficult to identify a single fiber.

    Can you post a picture of worst case scenario?

    Are you certain that you are able to identify which fiber each skeletal component (line segment?) is associated with?  i.e., are you sure that you are not computing the sum of lengths of the skeletons for all of the fibers in a clump?

  • Fateh Mebarek-Oudina added an answer in Political Socialization:
    Who is a sycophant? Is sycophancy an Art?

    We see sycophants in all the fields - political, social, administrative ......

    Do you think it is an art that is harmless or something that harms the organisational culture severely.   

    What kind of sycophants are prevalent in your part of the world.

    Fateh Mebarek-Oudina

    It is easy enough to describe the sychophant as a perversion or perhaps inversion of the ideal of the volunteer prosecutor, but there has been considerable recent dispute as to what is about him that is perverse. ~ S.Todd

  • Nayar Gutierrez asked a question in Wood:
    Which algorithm would you recommend to generate a reciprocal frame structure?

    I am working with wood but when trying to draw a reciprocal frame there is a differential error that generates a unsymmetrical structure when total number of members are greater than 20.

    Thank you for your help.

  • Charles Francis added an answer in Gravitational Field:
    Is the clock rate of free falling clocks the same?

    In a gravitational field of a homogeneous spherical mass M, a sufficiently small mass B, compared to M,  is left free in the gravitational field of M at a certain distance H from the center of mass, outside his surface. B gains speed, relative to the center of mass M, because of gravitational attraction. Many small objects like B free fall from different heights or from the same height at different instants.

    Every object has an atomic clock on board. Would these clocks have the same clock-rates during the free fall?

    A reference, master clock has to be adopted, otherwise the problem is ill posed. Clock-rates are refererred to an atomic clock on the surface of M for example (negligible M  rotation speed).

    The time elapsed for each body to go from the same starting and ending point counted by the atomic clocks on board is certainly the same (UFF).

    Their clock rate should be different, in general, unless they start from the same position and instant. Not because  light takes less time to reach the closest, since they are in different positions, but  because there exists a  relation between the very small object and the massive object.

    I would like your opinion regarding this problem.

    Charles Francis

    GR is based on the SEP according to which no difference can be detected between a free falling RF and a RF in flat space time far from masses.

    Stefano, can you detect a difference between flatness and the curvature of the Earth on a town map? Then how can you object that general relativity also uses the idea that a small enough region of spacetime is not distinguishable from flat?

  • José Navar added an answer in Water Supply:
    How to assess the impact of climate change on surface water supply system ?

    I want to assess the impact of Climate Change ( precipitation, temperature, salinity intrusion) on water supply ( surface water ). For this I do not get proper literature. Kindly suggest me some references and your views to do the work.

    Thanks & Regeards


    José Navar

    Be careful with the use of climate change or climate variability.

    For climate change, use one of the several models that run with one or several of the climate change scenarios; the Canadian Climate Change Model; The Goodard Climate Change Model, among others. Once you run the Climate Change Model for one or several scenarios (Based on Greenhouse emissions and policies) then you will have changes in any of the climatic variables you mentioned (precipitation, temperature, river discharge, and so on). Compare the normal or buisness as usual scenarios with the data given by the model and there you have your answer.

    Should you choose to use the climate variability approach, you have to carry out a past analysis of river discharge data and look for the maximum upper and lower natural variability. Transpose the lower variability into the future; let say for the year 2050 with increased river flow demands (increasing population, industry, agriculture and environmental issues) and then you have a contrast between what may happen in case of repeating the lower scenario of natural variability into the future with larger river flow approapriations.

    Hope this information is useful to you.

    Best Wishes and Kind Regards


    Jose Navar, Ph.D Oklahoma State University

  • Wen-Lian William Lee added an answer in Phosphors:
    What does mean quantum efficiency of phosphors ?

    In luminescence analyses, what does mean the quantum efficiency of the phosphor ? and how we can calculate it ?


    Wen-Lian William Lee

    Great and Thanks

  • Richard Marcley added an answer in Climate Change:
    Is it time we shift emphasis from technological solutions to climate change & focus on the 'Human Dimension'?

    Isn't the obvious solution and the elephant-in-the-room 'BETTER HUMAN BEINGS'? Shouldn't the focus be on better human beings rather than better technology? Why is it that everyone wants to develop better technology rather than focus on better humanity? Because no one has the answers and no one wants to change themselves? In environmental degradation, is it not obvious that nature can heal itself, if only left alone, and it is we humans who need regulation? Many natural parks managers do just that; seal off the area from human interference to let nature heal and recover. It is classified as 'Strict Nature Reserve"by IUCN. Complacency and inaction are not advocated here, as many have misunderstood, but the shifting of focus from technology to the human being. As technology is no match for human greed, isn't introspection & restraining ourselves more relevant than developing more technology, which caused the mess in the first place, by making it easy for a few to consume more? Since technology is only a short term quick fix which fails after a short time, isn't the real problem our addiction to material consumption & our lack of understanding about human nature? Isn't developing more technology sustaining the addiction instead of correcting it, leading to more complex problems later on, needing more complex technological quick fixes like higher drug dosages, more ground troops & equipment, (along with their debilitating side effects) in the future? Isn't this the vicious addiction circle we are trapped in? As researchers, do we merely buy more time with technology OR go to the very root of the problem, the human being?

    A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?

    " Our studies must begin with our selves and not with the heavens. "-Ouspensky

    Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests.

    We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
    Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions by now, given the amount of money plowed into finding such solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
    Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
    Aren't we addicts denying our addiction and blaming everything else but ourselves?

    " We are what we Think.

    All that we are arises with our thoughts.

    With our thoughts, we make the world." - Buddha 

    IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!

    The Mind is the Final frontier.

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    Richard Marcley

    Addiction is a "self" problem exacerbated by culture or lack there of, genetics, and hopelessness. The addiction the world suffers from I see more as an economic issue that could be regulated, if we have the courage to demand it of our leaders in government and industry. In tandem, we are victims of comfort, convenience, and necessity. Our lives are driven by the lash of economics, with a 1% controlling all the wealth, both parents work, kids are latch key etc. etc.

    I agree we need to evolve but that would require a major shift in economic realities for the 99% to allow them (US) time for the inner view. The 1% needs to be eaten, albeit hard to clean. Seriously, we need to reign in the !% and as a regulator I see strong robust regulation, expanded tax basis for infrastructure, reduction in work hours, child care, and subsidies to the developing world.

    We need a paradigm shift on multiple fronts that can begin with strong green house regulation, tax reform, and education. We need to prepare for a hard rain that's acomming. It may be too late, wait to the permafrost is no longer permanent. Wait to millions of Bangladesh starving refugees move to India and Pakistan, once their rice field are under water. We just might not have time for inner reflection when civilization collapses.

    Not too hopeful am I. Bernie Sanders is a small light in the dark here in the US. We need to reign in our old economic model, yesterday. How can corporate interests that control the flow information via their solely owned news feeds be stopped. Perhaps Bernie can be a catalyst for change. Not divine, just a guy from Brooklyn.

    I digress, we could in-act regulation in a short period of time. It will hurt and make for big change. It must be done quickly. Now how do we make brotherhood and the higher principals of all the major religions popular. Never mind gay marriage, woman's vaginas, and the slippery slope of helping the poor  as an offshoot of religious freedom.

    Maybe better government and culture can make better people. Disco is not dead, big hair is cool. Let's get advertisers in on the action.