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  • Jorge A. Quirós-Rodríguez added an answer in Marine Gastropoda:
    Is this Crassispira cerithoidea?

    This specimen was colected in Bocapan, north of Peru in sand substrate.

    + 1 more attachment

    Jorge A. Quirós-Rodríguez

    I agree with the suggestion of Jackson that it could be Crassipira cerithoidea


  • Maike Effern added an answer in Cancer Stem Cell Biology:
    Has anyone ever done RT qPCR for MEKK1 in human cells and can provide me with primer sequences?

    I am using gefitinib to inhibit the EGFR. I want to perform RT qPCR on EGFR target genes to make sure the drug is actually working.

    Maike Effern

    Hi Cora,

    I have never done RT qPCR on EGFR or its targets, but perhaps one of the following two websites  can help you create your own primer pairs:



    Good luck

  • Sattar Shah asked a question in Stone Fruits:
    Which method is best for Identification /Isolation of Brown rot in stone fruits. Mycology ?

    Which method is best for Identification /Isolation of Brown rot in stone fruits?Mycology?  

    Mycology (fungal disease in fruits)

  • James Kellermann asked a question in Impulse Control Disorders:
    Has anyone diagnosed or worked with a child or adolescent who was diagnosed with Parkinson's Disease?

    Did they have any distinguishing motor function disorders? Did they have non-motor functioning disorders, such as impulse control disorders, etc?

  • Eyad Abushandi added an answer in Regression Analysis:
    Can regression analysis be adopted as a tool for prediction of water levels?

    I have come across studies attempting to predict future dam water levels (in Nigeria and Pakistan), using different approaches (artificial neural networks, SWAT model). I am interested in developing a tool that would use readily-available climatic data (mainly precipitation, evaporation and temperature) to conduct analysis of variance and ultimately predict water levels for a given reservoir/catchment.

    Eyad Abushandi

    yes, linear regression analysis can be adopted as a tool for prediction of water levels. but you need to make sure that there is a significant correlation (e.g. Pearson) between the parameters you choose and water level. SPSS can easily do that.

    Good luck  

  • Hameed Lafta added an answer in Structural Health Monitoring:
    I have mass and stiffness matrix, how do I find the damping matrix, since I don't know have any values?

    Well, I m working on structural health monitoring of the mechanical systems, as a part of the research, I m working on the problem called cantilever beam. As a case of, I modeled cantilever beam to my requirements. however mass and stiffness matrix of the continuous beam is obtained using ANSYS. But, the problem is I need damping matrix to be obtained without using ANSYS. can someone explain me theoretical formulation and methodology to define the damping matrix using stiffness and mass matrix? 

    Thanks and regards


    Hameed Lafta

    damping it is a physical parameters and it is depended on your model that you may adopted. in a cantilever beam if there is no external damping, there are many researches dealing with the addition of internal damping which its called structural damping.  

  • Stefano Quattrini 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.

    Stefano Quattrini


    "Relativity (Special and General) has been passing all the tests of its validity (within the limits of experimental accuracy) for a century. So what is your problem? I may be wrong, but I have an uncomfortable feeling that you want to find faults in the theory, for some subjective reason. People with that mind-set are usually cranks; you are obviously not one, so I’m puzzled. I can only think that you are playing “devil’s advocate” to get us thinking. If that is so you have succeeded admirably (-:"

    What is my problem? Is that 

    1) only some experiments have been performed for GR and SR

    for GR the experiments performed regard situation in which a net exchange of energy is not present. GR is valid whenever I treat light, time dilation, periodic motion of planets or gravitational waves.

    Why nobody performed experiments with free falling clocks one on top of the other?

    2) SR has been postulated out of Classical mechanics in the Poincarè group, it generalizes classical mechanics of the point but only that one since it is based on the mechanics of the material point, you cannot draw anything else and it works very fine in accelerators.  

    "People with that mind-set are usually cranks; you are obviously not one, so I’m puzzled. I can only think that you are playing “devil’s advocate” to get us thinking. If that is so you have succeeded admirably (-:"

    So I know very smart cranks....what should I say...

    This manichean attitude to classify in Geniuses and Crackpots does not bring very far.  The impossiblity for a theory to have limits of applicabilty is not acceptable in the same way others affirm that it is totally wrong.

  • Charles Hogg asked a question in Helicopters:
    Looking for Journal of the American Helicopter Society Vol. 33 No. 4 Oct 1988?

    Looking for article on Pitt-Peters dynamic inflow model and equations.

  • Rahul Mondal asked a question in Fish Nutrition:
    Kindly suggest me some well known journal where I can publish 'SHORT COMMUNICATION ARTICLE' on FISH NUTRITION releted work?

                    We did a small experiment on FEED releted study on shrimp juveniles. We want to publish our work. Please suggest some journal name where we can publish our work as a SHORT COMMUNICATION ARTICLE.

    Thanking You,

    Rahul (India)

  • Alfredo Oliveira added an answer in Quantum Mechanics:
    Are there any of the mysteries of physics that are beyond our intellectual capacity to conceptually understand?

    Richard Feynman said, "If you think you understand quantum mechanics, you don't understand quantum mechanics.” Is the problem that the human intellect is incapable of understanding some aspects of quantum mechanics or are we merely missing a model which will make the mysteries of quantum mechanics conceptually understandable? Another quote attributed to Feynman is “Shut-up and calculate”. This implies that a student is being told to suppress their natural desire for conceptual understanding and instead work on mathematical analysis. Do you feel that some questions are beyond our intellectual capacity to successfully answer? If so, perhaps you should identify these to stimulate discussion. For example, questions about the composition of fundamental particles or string theory strings are often treated as unanswerable. What are your thoughts?

    Alfredo Oliveira

    Dear John, a very interesting question indeed. 

    I think the the universe is as simple as it can be, that our knowledge of it is just in the very beginning and that there is a lot more of it that we can understand. However, there is different matter related with this, which is: are we capable of discovering it? because one thing is understanding, other is discovering.

    For instance, anyone can easily understand now the Newton's model; however, to discover it, it took a long time and the work of persons that were considered "genius", persons with capabilities above normal human ones.

    To discover requires a knowledge and a methodology which is largely ignored by scientists; worse, the capabilities required are repressed; that is a serious problem. And it last for long, that is why very important contributions were made from persons that did not belong to the scientific system (Newton, for one).

    There is another aspect which is the following: we cannot state that the universe is understandable and we do not understand it; because that causes stress, fear, frustration. Therefore, we state that it is not understandable but we are so fantastic that we can still have some control over it, making use of tools that surpass human capabilities like maths!!!!  And once it is not understandable, we can make crazy hypotheses, dark matter, dark energy, wharmholes, colliding universes, multidimensions, Higgs boson, neutrino flutuation of state, and so on - and that makes science very popular. So, to state that the universe is not understandable is much more convenient for everybody (except for those that want to understand it)

  • Kåre Olaussen added an answer in High Energy Physics Theory:
    Why nobody see that Higgs boson and gravitational waves are the pure theoretical failures?

    Higgs boson does not interact with gluons which give energy for 99% of proton mass. How the Higgs boson gives mass to the proton, nobody has no clear answer. Why are we closing eyes and tolerating this model which does not have a minimal correspondence with physical existence? Energy and mass are both inherent physical properties of every particle. No particle can give mass to another particle; this is a complete misunderstanding. Higgs boson  does not prove anything, Higgs boson is artificially made flux of energy and nothing more. 

    Energy and mass are both inherent physical properties of every particle. They have the origin in the diminished energy density of quantum vacuum.  A given particle cannot be examined without this diminished energy density of quantum vacuum which determines its energy and mass. The idea that particles exist in an empty space deprived of physical properties is the biggest theoretical failure of physics since its existence. It has led  to the idea of Higgs field and gravitational waves which are both pure theoretical failure. No particle can give mass to another particle; this is a complete misunderstanding. Higgs boson  does not prove anything, Higgs boson is artificially made flux of energy and nothing more. And no wave can transmit gravity. 

    Kåre Olaussen

    Anton> sum over all positive reals which is infinity even for a "small" interval!

    Actually, what is relevant is not the total energy (because the universe may be infinite), but the energy density. This is most conveniently calculated by assuming a finite universe (periodic boundary conditions), which provides an infinite discrete set of possible frequencies, and next take the volume to infinity. In the end this leads to an integral which diverges in a rather rational way, not like the number of (mostly irrational) reals :-)

    This is how bulk energy densities are computed in condensed matter physics (when one doesn't need to think about surface corrections).

  • Ghulam Sarwar Shaikh added an answer in Mathematical Analysis:
    Under what condition the whole sequence convergent if the subsequence in L1 space is convergent

    under what condition the whole sequence convergent if the subsequence in L1 space is convergent

    Ghulam Sarwar Shaikh

    Following two papers may be help full for you....

    + 1 more attachment

  • Jadranka Stojanovski added an answer in Peer Review:
    Is it right to inform an editor that the reason why you won't review a paper is because you peer reviewed the same paper earlier for another journal?

    Assuming a paper you reviewed earlier is sent to you by an editor of another journal, is it right to inform the editor that you will not review it because you earlier did for another journal? Will such revelation affect the acceptance of the paper in the new journal?

    Jadranka Stojanovski

    Agree with Loay, it depends. It's not clear what was the result of your (first) peer review. If you suggested the editors the acceptance of the article, then you should check with editors about their intentions to publish a paper. If your peer review was not positive, then  "second try" is somehow expected from authors.
    Your question also raises an importance of the feedback from the editors, after peer review process ends. Usually the reviewer is not informed about other reviewers opinions and editor's final decision.

  • Manidipto Mukherjee added an answer in Materials Engineering:
    How can we identify that a particular intermetallic or precipitate is anodic or cathodic ?

    For example - Mg32(Al,Zn)49 is a precipitate in aluminium alloy 7075

    Manidipto Mukherjee

    check the link below. It may help


  • Kourosh Ahmadi added an answer in Species Distribution Modeling:
    Which remote sensing data is suitable for plant species distribution models?

    I need information about RS data for species distribution of trees

    Kourosh Ahmadi

    Thank you for your useful comments

  • Brian Karl Richards added an answer in Nitrogen Cycle:
    What is the most popular method to measure Methane emission from agricultural activities?

    In this case, I want to measure Nitrogen cycle including N fixed in soil, N uptake by plant, N leaching and N emission.  

    Brian Karl Richards

    Emissions measurements of methane and nitrous oxide are challenging due to the high variability in fluxes across both time and space. Soil chambers are the least expensve means of collecting gas samples but require gas analysis instrumentation to quantify methane or N2O. Their corresponding weakness is that they represent only a "snapshot" of emissions at a specific time and place. In contrast, field-scale micrometeorological methods such as eddy covariance or gradents determinations can provide time-continuous measurements, but are extremely expensive and yield only a spatial average emission from the upwind "footprint" area. I can attach a reprint from our former PhD student that illustrates the interplay of these two approaches for nitrous oxide emissions.

  • Muhammad Azaz asked a question in Laptop:
    Modules and functional requirements of laptop tracking system ??

    modules and functional requirements of laptop tracking system ??

  • Eyad Abushandi added an answer in Green Architecture:
    Can anyone refer me to papers regarding recyclling construction and household waste to high quality sand?

    I'm interested in the topic of manufactured sand.

    Eyad Abushandi

     Hi, you could see these papers: 

    1. https://www.researchgate.net/profile/Ana_Barros5/publication/4867339_A_Two-Level_Network_for_Recycling_Sand_A_Case_Study/links/5477374b0cf2a961e4824227.pdf

    2. http://www.sciencedirect.com/science/article/pii/S0921344904000655

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: In the Netherlands, the recycling of construction waste and in particular of sand creates an important logistic problem. New legislation ensures that disposal is reduced to a minimal level and this incentives recycling. Such measures cause an increase on the offer of sand (a subproduct of recycling construction waste) and create the need for establishing an efficient sand network. The sand problem falls into the field of reverse logistics management since it deals with processing returned goods (sieved sand). We propose a two-level location model for the sand problem and consider its optimization using heuristic procedures. The results obtained for the sand recycling network in the Netherlands are summarized.
      Full-text · Article · Feb 1998 · European Journal of Operational Research
  • Kamlesh Sahu added an answer in Molecular Docking:
    I am new in the molecular docking field, could you recommend me resources to get a good beginner background?

    I am a student and a complete beginner. I have read a lot but I wanted a suggestion about any material that could help me clarify ideas about the biophysical basis of molecular docking. 

  • Norah Asiri asked a question in Gaussian:
    Difference between Gaussian and Laplacian distributions for multivariate data?

    Dear all,

    I have question about the difference between Gaussian and Laplacian distributions for multivariate data.

    Thank you

  • 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

    Wow too much naval gazing here, if you ask me.

    Try this, next time your at the super market take all the items you purchased out of the packaging and leave it at the store. Demand the banning of plastic shopping bags as well and encourage use of personal tote bags.

    Walk to the store, demand mass transit. Enforce a carbon tax with a bite, subsidize developing countries to reduce use of carbon and promote forests and wetlands.

    Make a national priority to go renewable akin to the war effort. Buy local, encourage small and diverse farming. Make manufacturers and corporations pay the full cost of their practices and policies.

    Elect leaders that understand or at least respect science. Overthrow those that do not. 

    Review the whole capitalistic model, where growth is the driver. Think of it as cancerous to the planet, it is.

    Regulate industry, financial institutions, and agriculture for the good of the people and not individual shareholders. Place a good set of teeth into these regulations and use them. Inform and expose with an active press. Monitor the press for propaganda and impose penalties for violators.

    Educate our children to maximize their potential to our collective benefit.

    Have Jesus, Buddha, Mohamed, Zoroaster, the Great Pumpkin all (actually one and the same) appear and make humanity realize we are on a small speck of dust floating in a hostile, cold vacuum, that does not care about life.

    Short of that we are screwed. We are.   

  • Hameed Lafta added an answer in Electron Beam Welding:
    What is the meaning of response time of thermocouple temperature measurement during electron beam welding ?

    i do my research on measurement of temperature  during electron beam welding.

    Hameed Lafta

    response time it is a measurement of speed of response of thermocouple to temperature change and it is may be called (time constant)

  • Sachin Madeti added an answer in Finite Element Analysis:
    UMAT ABAQUS: Structural Relaxation implementation..?

    I am trying to simulate a molding process of glass:

    I have implemented the standard Burgers model into UMAT abaqus. I have defined both Stress(DSTRES) and Tangent Modulus (DDSDDE) equations.

    In Step 1: I have fixed the lower mold and displacement for the upper mold was applied (ramp over time). Simulation is working good and successful.(PFA)

    In Step 2: Here i am not sure about the values for Tangent modulus and Stress. I have read in a paper about Prony series.. 

    Do any of you have a sample UMAT code for prony series on how it should be implemented to the calculated stress in STEP 1.

    Sachin Madeti
    Thanks a lot Anshul.. Small doubt..
    Please let me know, can we use UMAT in the step-1 and then in the step-2 (ABAQUS prony series) to simulate the relaxation..?
  • Maryam Abedi asked a question in Repair:
    How can I find a list of drugs that have role in tissue regeneration and repair?


    I need to select some drugs that are important for regeneration and repair. Is there any database that helps me to select drugs based on this criterion?



  • Hazim Hashim Tahir 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.

    Hazim Hashim Tahir

    Dear Colleagues,

    Good Day,

    "The terms absorption and adsorption are used freely to indicate the same process of taking moisture from the air using desiccants, mostly because we don’t want to complicate the explanation of what our product does. But there is a difference.

    Absorption generally refers to two phenomena which are largely unrelated. In one case, it refers to when atoms, molecules, or ions enter some bulk phase – gas, liquid or solid material. For instance, a sponge absorbs water when it is dry.

    Absorption also refers to the the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make transition between two electronic energy levels. The photon is destroyed in the process. The absorbed energy may be re-emitted as radiant energy or transformed intoheat energy. The absorption of light during wave propagation is often called attenuation. The tools of spectroscopy in chemistry are based on the absorption of photonsby atoms and molecules.

    Adsorption is similar, but refers to a surface rather than a volume: adsorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid or, more rarely, a liquid (adsorbent), forming a molecular or atomic film (the adsorbate). It is different from absorption, in which a substance diffuses into a liquid or solid to form a solution.  This is what happens to calcium chloride desiccants in container shipments.

    Sorption encompasses both processes, while desorption is the reverse process."

    Please, see the link...

  • José Miguel Urra added an answer in Flow Cytometry:
    What is the best early T-cell activation marker for swine in Flow Cytometry?

    I will perform an intervention invivo and let the swine live for 10 hours and harvest my test samples(blood and Lymph node). i will perform Flow cytometry to look for change in the percentage of activated T-cells.

    I need recommendation of early activation antibodies to use.

    José Miguel Urra

    The activation of T lymphocytes and Natural Killer (NK) Cells, both in vivo and in vitro, induces expression of CD69. This moleculeappears to be the earliest inducible cell surface glycoprotein acquired during lymphoid activation.

    Hamann J, Fiebig H, Strauss M (1993). "Expression cloning of the early activation antigen CD69, a type II integral membrane protein with a C-type lectin domain". J. Immunol. 150 (11): 4920–7. PMID 8496594.

  • Victor Aguilar added an answer in Economic Modeling:
    Do you think oil will continue to be an economic model in the future?

    There was a period in history when gold was a major economic model in global economy. Latter other models like silver, copper etc followed. Finally oil emerged which has become so powerful economic model. With the current global shake in the oil market and the quest for both developed and developing economies on alternative energy, is it possible for oil to phase out in the nearest future?

    Victor Aguilar

    Here is a paper I wrote in 2006 about the origin of money, first based on cattle, then gold and then dollars.  This does not have anything to do with whether the current price of oil will go up or down, though I am not sure that the use of the word "model" in the question had anything to do with current prices going up or down either.  I also discuss how chips from the major casinos in Las Vegas function as a sort of money in the local economy.

    If oil exports from the Middle East were shut down by the Iranians closing the Strait of Hormuz during a war, it is possible that IOUs for oil might start trading like money and, even after the strait was reopened, they might continue to function as money.  

  • George Zafiropoulos added an answer in Total Knee Arthroplasty:
    Has anyone encountered stress # of fibula after TKA?

    She has history of acute onset of pain 3 months ago, with progressive valgus deformity of the knee.

    + 1 more attachment

    George Zafiropoulos

    Dear Raju

    This is very interesting. I haven't seen this before.

    Do you think that the fibular fracture could be present as hailine fracture at the original x-rays following the injury resulting the periprosthetic fracture 3 months ago?

    I am mentioning this as the fibula is healed with good callus.

    Also, the valgus position, is it possible to be the result of soft tissue imbalance as result of either collapse of the fracture during the healing process or due to that position the fracture was fixed?

    I am saying this because she has, in my eyes, patella baja. On top of this the distal femur is placed in some extension so there is the possibility of some comminution due to the patient's osteoporosis.

    X-rays of the fracture before surgery may help.

    This is very interesting problem and I can see the solution with a potential revision of all metalwork with a hinged prosthesis if necessary. All depends on patient's clinical condition.

  • Edmund Selorm Sosu asked a question in Literature Review:
    What informs the construction of a conceptual framework? Does it stem from the literature review or the problem statement?

    What informs the construction of a conceptual framework? Does it stem from the literature review or the problem statement?

  • Rafik Karaman added an answer in Contact Angle:
    What is the best method to find out the contact angle (theta rec and theta adv) from a two dimensional figure of a drop as given below?

    image processing

    Rafik Karaman


    Herein the link for the chapter mentioned in my first anser: