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  • Francis Steven Mickus added an answer in Art:
    Do we need any definition of Art?

    I´am wondering if we need any kind of definition of Art. In the last period of time, the Fine Art lack any boundaries, or rather should I say any bounderies that couldn´t be falsified. For example if some artist make sincerely a piece of Art and react on something, and some years later, somebody else make something simmilar but inspired only by succes of the first artist and we recognise him, is the second artist also real artist and maker of Fine Art? So I think, there should be some ground rules, and we couldn´t just agree with everything. What I am trying to say, is that despite the overcome normativity in art there should be some rules.

    Francis Steven Mickus

    i used the tautology to hammer my point.

    Everybody here seems to be tying themselves up in knots because they refuse to accept the obvious: to accept a serious debate ther must be some agreeement as to the the terms of the debate.

    To say that art cannot be defined is basically to say that art is meaningless - which i don't think is true.

    Whether art is made in small factories or great industrial complexes is beside the point (Hell, a good friend creates his works in his garage, and they are masterworks).

    There has to be a general agreement as to what we are talking about for us to get anywhere. As I said right after, there needs to be a shared framework for there to be a coherent debate.

  • Nick Hamburger added an answer in Hydraulic Cylinders:
    From where can I get review paper on vibrations in hydraulic cylinders?

    please give me title and author details

    Nick Hamburger

    You have to consider the cylinder as a mass (all inertia connected to the moving part of it which can be either piston or body depending on application) connected to the fix part by 2 stiffness (the 2 volumes on the 2 sides of the piston), the fixed part connected to the fixed reference via a spring (compliance of the supporting structure) and with a friction between fixed and moving part. The problem will always be the nature of the friction. The sealing elements can under circumstances run dry which leads to a Coulomb type of friction and to stick-slip effects. This means that the seals-guide-bushing material plays an important role in the apparition of oscillations.

    This is the case when internal friction is the reason. In some applications the reason is external especially when the inertial load combined with the cylinder own compliance leads to an own frequency near to those appearing in the course of the working cycle. In this case for instance a sharp stop can lead to oscillations.

  • Cyril Mechkov added an answer in Circuits:
    Who knows the properties and the working principle of this circuit?

    Recently I came across with the shown circuit.

    It has some interesting properties. Is there anybody who has used such a circuit already? Both opamps are assumed to be ideal.

    Cyril Mechkov

    Lutz and Dobri, I can not understand at all what you are arguing here... There are two single-ended voltages (v1 and v2) in a proportion 1:2 that, of course, are referenced to ground... but we use their floating difference as an output voltage...

  • Rathnavel Pon added an answer in Environmental Engineering:
    Is there any relationship between BOD (Biochemnical oxygen demand), COD (chemical oxygen demand), SS & conductivity in the water analysis parameter?
    We want to find the link between the Water treatment parameters, may be software or it can be a graphical relation.
    Rathnavel Pon

    In that case, I think a regression analysis may be done to find correlation between the parameters. The success of the correlation would also depend heavily on the quality of effluent conducted during that study. Some parameters may change with time and space. 

    I suggest determining all the four parameters independently. In the worst case, BOD and TSS may be calculated while COD and Conductivity can be deduced from the values of BOD and COD

  • M D SUBASH Chandran added an answer in Fisheries:
    How to asses Impact of Fishing in tropical estuarine ecosytem where small scale fisheries practiced?

    How to asses Impact of Fishing in tropical estuarine ecosytem where small scale fisheries practiced?.........................................................................

    M D SUBASH Chandran

    I am not a person to venture with an answer to this question to an expert in this field. I feel still that certain ways could be thought of impact assessment of small scale fisheries inn an estuary. If overdone this fishery will lead towards depletion.

    Socio-economic survey may be required in the first place. How many fisher persons depend on the estuary. How much per person area (in ha) is available in the estuary on average. Through field sample survey it needs to be ascertained how many fishing days collectively are happening in the limited area of the estuary.

    Of the commercially important fishes what is the average effort for fish catching and what the returns are, in terms of species-wise average size and quantity caught. Is there any reduction in size classes and quantities of fish caught over the last many years (through interviews)? Is there any change in mesh size of fishing nets? What is the current management regimes to govern fishing? If there is none could it not be a reason for non-sustainable harvest- if the same is happening? Whethehr the demand for estuarine fish has increased? Whether the markets have expanded to cater to wider circle of consumers? All these could be the first be to gathered before devising next set of questions.

    Dr M D Subash Chandran

  • John Poke asked a question in Natural Resource Management:
    What are some problems with the sustainable development concept?

    natural resource management

  • Bartłomiej Dybowski added an answer in Material Characteristics:
    Dear All, How important are the materials A359 and Hastelloy C276 in industries?

    Dear All, How important are the materials A359 and Hastelloy C276 in in

    Bartłomiej Dybowski


    A359 is one of the most popular aluminium casting alloys.  It is widely applied in automotive industry as well as in the power generation industry. It is characterized by a good casting properties and acceptable mechanical properties. Many elements which are not heavily loaded are cast from this alloy.

  • Malur Srinivasan added an answer in 3D Printing:
    What is the influence of infill %, layer height and infill pattern on 3D prints models made of ABS???

    Looking for same/similar info as here: http://my3dmatter.com/influence-infill-layer-height-pattern/ but according to ABS filament.

    Malur Srinivasan

    I sincerely hope that you will find information you are looking for pertaining to ABS.I fully appreciate the difficulty in developing PLA-style information as provided in the attachment sent by Dr. Pradhan. My personal feeling is that PLA, being recommended for industrial use, has attracted more attention of researchers as compared to ABS which seems to be more popular for personal or limited application use. I wish you success in your search.

  • Monireh Bakhshizadeh asked a question in Lithium Ion Batteries:
    How to apply least square method in a Preisach model of Lithium-Ion Battery?

    I'm using the preisach model to simulate OCV-hysteresis of a LFP battery. I have an underdetermined equation system from my OCV-SOC measurements. Therefore, I want to use the least square method to find the weights of the Hysterons. For that I use the Matlab function lsqnonneg.

    Problem: lsqnonneg gives me a solution, by which the most weights are zero. Almost all of the non-zero values are on the diagonal of the preisach plane, which results in a non-representative model of the hysteresis.

    Can anybody help me to find a solution for this problem?

    Many thanks in advance.

  • 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.

    + 2 more attachments

    Richard Marcley

    I was thinking about that on the ride to work this morning. Any strong leader could go that way. That is why a movement is needed.

    Here in the US people are incensed about gun regulation. Some fools think carrying guns into churches, schools, and bars is an exercise of their god given freedoms. Guns kill more people than auto accidents and a order of magnitude more than any terrorist attack. These gun toting fools are more than willing to give up their rights and subvert the basic tenants of the BIll of Rights. They reject the very soul of America with CIA snooping, baring entry into the US based on religion affiliation, our black youth  being killed and jailed in world record proportions, in the name of safety. So yes the danger of slipping into totalitarianism is real. A good portion of the US is ready and eager for it e.g.. Trump, Cruz, GOP. fascism, oligarchy, inquisition. 

    Climate change will destroy civilization, that is fact. After the chaos of displaced millions escaping starvation upsets the world order. Governments will lean to a strong leader with xenophobic, and often violent  response. It is already happening, much to my disgust.

    We can change behavior if the people are motivated through knowledge. If they can see a better life without the plastic trash, poisoned water, and meaningless lives. We can build a strong economy around green works. First we need to take control of the economy and industrial practices. We need to take down the puppet masters and propagandists.

    Our ecological behavior has been subverted for generations. What I argue for is a return to our biological roots and our native habitat; small scale and sustainable. A 40 hour week in a cubicle, isolated from family and society can not be satisfied with a warm gun. So yeah if its totalitarianism to take away you gun in church or school so be it. Same applies if gas is 20 bucks a gallon and you got to ride mass transit paid for through taxes.

    The alternative a lot more dire than the risk of "control" of ecological behavior. Incentivize, enable, the good and discourage, penalize, and tax the bad.   

  • Brittany Saggau asked a question 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?

  • Marko Popovic added an answer in General Relativity:
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Marko Popovic

    Dear professor Prástaro 

    Thermodynamics is very clear.

     Based on the ideas of Lord Kelvin, Joule, Boltzmann, Carnot, and Clausius, the first and second laws of thermodynamics can now be restated in two profound sentences:

    - The total energy of the universe is a constant.

    - The total entropy of the universe always increases. delta S universe >0.

    Equation is clear. delta S = nR ln (V final/Vinitial) assuming delta Suniverse>0.

  • Bruce E Oddson added an answer in ANCOVA:
    Is it reasonable to use the Hedge d (or g) in case of linear mixed models?

    I would like to compare some studies using the Hedges'd (or its unbiased estimate g). but in both case i have a hierachihcal structure of the data related to transect representing a secondary level o sampling which correlate some of the observation. I was wondering to simply apply an ANCOVA using this transect as a covariate (could it be done?). It would be surely better to use a mixed model with transect as random effect factor, but in this case may I us this Hedge statistics? How could i adjust for the random effect factor?

     I use R, thus lme4 package for mixed models and the compute.es for the effect size

    Bruce E Oddson

    Dear Lorenzo,

       It makes perfect sense to me that the model F would be reasonable. What makes me wonder is the case where it does not work - normally this sort of "surprise" tells me that I am not estimating what I think I am. If I think about marginal means being inappropriate it might mean that the joint distribution of my variables is such that I am introducing a problem if I ask the software to "pretend" that the mean estimate can be done over the average values of everything else. One example of this is an interaction between the variables that is not in your model; another could be partially connected error variance. 

       Anyway, how far you wish to go with this given that you already have a good answer is up to you. I will think about it!

  • Behnam G.hosseinzade asked a question in Microgrids:
    What research priorities do you suggest for my dissertation ?

    in these branches :

    1. power transformers
    2. power electronics
    3. smart grids and microgrids

    thanks for your times

  • Melanie Poulin-Costello added an answer in Propensity Score:
    How to match individually on propensity score in SAS v 9.4?

    I have a dataset of 60,000 women with a propensity for vaccination ranging from around -0.5 to 1.5. What is the best way to individually match these women on propensity score in SAS? I know how to do this by creating multiple datasets, but I'm hoping there is a function that could save a lot of time/work? 

    Melanie Poulin-Costello

    Hi Annette - Propensity score is a conditional probability, so I'm curious by your statement of propensity ranging from -0.5 to 1.5.  What methods are you using?  

  • Svante Hedström added an answer in Quantum Chemistry:
    How can I calculate the natural transition orbitals analysis (NTO), and visualize it?
    Svante Hedström

    Somanda and Nathan: often the 1st transition is strongly of HOMO-LUMO character, so you won't see any difference between the NTOs and the canonical HOMO and LUMO. Try higher excitations, e.g. transition=2 and see if there is a difference.

    In the normal td-calculation, there is printed the contribution from a specific pair of orbitals to the transition. If the 1st excitation has close to 0.7 coefficient of HOMO->LUMO, then the NTOs for that transition will be identical to the "normal" (canonical) HOMO and LUMO.

  • Hadi Ostadi added an answer in Lysis Buffer:
    What is the effect of triton x-100 on periplasmic protein extraction? Does it effect on unfolding of protein or increased LPS on protein solution?

    in lysis buffer I want to increase extraction of protein from periplasmic space of E.coli following by use of sonicator, Does it effect for better extraction?

    the excipients of buffer are: 20mM tris, 150 mM NaCl, 4M urea, 10mM imidazole

    thanks in advance

    Hadi Ostadi

    Thanks for your response, I checked it out in previous, this protein wont unfold in this concentration of  urea, this is my question: what the effect of this component for extraction of protein? Is it effective? I just want to increase extraction of protein which is absorbed  by the cell's wall to increase the recovery of extraction.

    Thanks in advance.

  • Luisa Isabel Rodríguez-Bello added an answer in Sorption:
    What is the difference between sorption and adsorption?

    In some of articles, we used different terminologies which make us confuse.

    Please help us with any comments, documents.

    Thank you in advance.

    Luisa Isabel Rodríguez-Bello

    It is a question about terminology, which can be solved consulting a glossary. Look at:

    Introduction to the Sorption of Chemical Constituents in Soils by Aaron Thompson  & Keith W. Goyne:


  • András Bozsik added an answer in Harmonia axyridis:
    Have you observed damage of Harmonia axyridis in fruits and grape?

    Dear All,

    H. axyridis has appeared in 2007 in Hungary. Since then it became one of the most dominant ladybird species. In recent years Asian ladybird adults caused substantial damage in fruit plants and grapevine here. The damage was quantitative and qualitative in vineyards. Mainly grapes with injured epidermis were attacked. Intact and healthy grapes were generally not damaged. The qualitative damage was due that numerous adults wandering towards overwintering sites aggregate on grape and growers cannot separate the ladybirds from the grape to be processed. The H. axiridis alkaloids spoil taste and bouquet of the vintage. As a consequence of this damage, grape growers call this beetle “bitter ladybird”. This coccinellid harms also apples and pears. Certainly, there are a lot of data and reports on this kind of damage mainly in US and France.

    Have you observed similar damage of Harmonia axyridis in your country? Have you experienced economic yield losses in various crops?

    András Bozsik

    Dear Federico,

    As to S. titanus control and troubles, the situation is similar in Hungary too: 2-3 treatments per season and the most dangerous condition is the prevalence of abandoned vineyards in vine growing areas.

  • Ennio Duranti added an answer in Chronic Renal Failure:
    Does any one know any clinical study comparing differences in drug plasma level taken from peripheral vein and AV fistula in patients on hemodialysis?

    The patients with chronic renal failure have to undergo hemodialysis. These patients usually have AV fistula. The question is if the blood can be collected from this AV fistula on the beginning, during or after the end of hemodialysis in order to avoid further puncture of vein. I suppose that values like mineralogram or pH will be completely different between these two approaches. But what about drug levels? Does anyone know any study dealing with this issue?

    Ennio Duranti

    You have to collect blood from the so called arterial line or the line directed to the dialyzer immediately at the start of the dialysis session . Only if you want   to control instant KT/V  or mass transfer you have to collect blood from the so called venous line or the line going from the dialyzer to the arm .

  • Panayot Tanchev added an answer in Implant:
    What is the exact definition of dissection, in surgery?

    If an implant of 0.5 cm is retrieved from animal subcutaneous space with single incision along with skin and gluing wound edges without any digital maneuver. Will it be called as dissection or explantation?

    Panayot Tanchev

    This implant was implanted before some time, and now you want to remove it. Explantation or extraction fits this kind of procedure. Dissection is not suitable because it does not elucidate the fact of implant removal. On the other hand, you may apply it as a first step of this procedure to free the implant from surrounding tissues, expose it and then as a second step -  extract (explant) it. 

  • V. T. Toth added an answer in Particle Physics:
    Any thoughts on the rigid state of matter p=\rho c^2, its properties and role in modern cosmology?

    For instance, in his famous paper "Particle Physics and Inflationary Cosmology " (see hep-th/0503203), Andrej Linde asserts  ( see ibid § 9.1) that the deskiy of the  p=\rho c^2 matters decreases quickly with expansion of Universe. Why it is so ? (grounding)

    V. T. Toth

    Dear L. D. Lantsman: It has to do with the speed of sound. The speed of sound in a perfect fluid with constant equation of state is given (in units where c = 1) as vs = √w. (It is a special case of the more general formula, vs2 = ∂p/∂ρ.) So if w > 1, we have vs > c, thus sound waves propagate faster than the speed of light, violating causality.

  • Debaprasad Koner added an answer in Antioxidant Enzymes:
    What are the best procedures for antioxidant enzymes measurement in serum and biological tissue and fluids with spectrophotometric?

    tissues include: liver, muscles and ovary

    biological fluids: serum and whole blood

    hen eggs and sperm

    Debaprasad Koner

    Dear Raei,

    GST activity assay by monitoring formation of the GSH-CDNB conjugate at 340nm.

    Kindly go through the attached file.

    Hope it will help 

  • Daniela Andonovska-Trajkovska asked a question in Social Care:
    How can an educational institution at the university level help elderly people in the sphere of social and health care?

     What are the options if there are possibilities for cooperation with certain institutions such as centers of social care or organizations of retired people? What kind of activities or workshops can be delivered having in mind the needs of social and cultural inclusion and a psychological and physical health of that kind of target population? The question targets elderly people as population, especially the ones that has been recently retired and have more free  time then they are used to have, or the ones that are older and are not able to use technology or resources that are available by many social services. It is also very important to note that they may have specific health issues due to unhealthy nutrition habits or to their age. How can we, as educators, provide help and actively participate in improving their quality of life?

  • Naveen Kalra added an answer in Phenology:
    Is there any very simple model for sugarcane growth?

    I have come across sugarcane model from Brazil, which I could not download, although I have copy of this model paper published

    Our interests are phenology prediction, biomass growth rates over a period of time, partitioning into plant parts, water-nitrogen stress effects, quality in terms of culturable sugar (CCS) (simple model)

    Model like QUEFTS to be modified for inclusion of Fe, Mn, B effects alongwith NPK (another vision)

    Phenology prediction like Sinclair approach 


    Naveen Kalra

    DSSAT has sugarcane, working well for potential estimates, needs to be calibrated/validated for indian/south asian environment. DSSAT can be a nice modelfor cane if calibrated/validated perfectly

    WOFOST model can be easily tuned for sugarcane if we have appropriate crop coefficients, specifically for major cultivars

    Brazil model, based on efficiency factor, our interest to look into

    if radiation use efficiency, water and nitrogen use efficiency, phenology is expressed, the simple model can be made


  • Tyler Chafin added an answer in Genomics:
    Whats the effiecient way to dealth with polyploid species having genome sizes range from 3.5 to 4.0 pg following the ddRAD protocol?

    We are going to do ddRAD protocol based sequencing by using Illumina Hiseq platform. Our modeled species are having polyploidy with genome sizes range from 3.5 to 4.0 pg. Our main concern is that how many individuals we need to pool and how many barcodes we need to use in libraries preparation to get enough amount of data with high coverage. Your precious suggestions and links towards related literature will be highly appreciated. Sincerely   

    Tyler Chafin

    For the simulated digest? I have used the script on genome sizes between 1 to 6 billion bases. Obviously you will need enough memory on your machine to load the entire genome at once as I didn't need to consider any memory issues with my hardware

  • Vinod Kumar Rajput added an answer in SEM-EDS:
    How Does the silicon content effects the Graphene oxide properties?

    I am undergraduate student. I've produced Graphene Oxide using Modified hummer's method. In SEM/EDS results it shows some quantity of silicon in final product... ?where does it come from!  

    Vinod Kumar Rajput

    Peter and Ian J, thanks to both of you for such guidance. After considering all this i'll give another attempt and will be back with other questions.. 

    Here I am attaching a SEM images produced GO! what do say about that?

    + 1 more attachment

  • William Smith added an answer in Analytical Chemistry:
    What are the drawbacks of multidimensional compared to one dimensional LC separation techniques?

    I need to know the disadvantages of using multidimensional in quantification purposes in both comprehensive and heartcut 

    William Smith

    You may also run into problems with dilution and the LOD in the second dimension depending on the initial sample loading, especially for complex samples.

  • Nicole J Fenton added an answer in Silviculture:
    Do you know of anyone whom has created a trait database for northern temperate or boreal lichens?

    I'm working with a colleague on impacts of intensification of silviculture on lichens. We have pre-, 2nd, 5th and 10th year post-harvest data from 156 two hectare experimental units. We will be offering co-authorship to those willing to share their trait database(s).

  • Catalina Maria Georgescu asked a question in Security Policy:
    Can we refer to the High Representative of the Union for foreign affairs and security policy as institutional innovations for the EU construction?

    What are the differences between the High Representative of the Union for foreign affairs and security policy and the former would-be minister of foreign affaires of the EU as envisaged by the Constitutional Treaty? Thank you