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  • Wallach Joe added an answer in Earthquake Forecasting and Geocataclysm:
    What is the relationship between earthquakes and climatic changes?

    What are the effects of climatic changes on the recent earthquake i.e. Hindu Kush earthquake (7.5 magnitude) that struck South Asia on 26 October 2015. What are the other possible causes of this earthquake?

    What are the possible reasons for the increased frequency of the earthquakes? Can anyone suggest the research articles which describe the relationship of climatic changes and earthquakes?

    Wallach Joe

    My apologies for not reading the entire question more carefully, Muhammad.

    I stand by my statement of their being NO relationship between climate change (more likely global warming) and seismicity. Earthquakes are caused when the tangential stress acting along a fault exceeds the resistance to movement along that fault. The greater the resistance to movement, the more strain energy accumulates. If the accumulated strain is great then its release will produce a large earthquake.If only a rather small amount of energy is required to induce slip, a small earthquake will occur.

    As an analogy, think of an empty cardboard box on a tabletop. It takes little of your energy to slide it, thus it slides smoothly with no jerking at all. Next load that box with about 35 kg of books (or rocks) then push it on the same table top. Initially you may not even be able to move it, but if you push harder it will move. This time, however, it will move in a jerky manner rather than smoothly, and it is that sudden, jerky movement that would be analogous to your earthquake.

    One more example. Take a small, wooden toothpick and a larger, plastic ruler, say about 32 cm long. The objective will be to break each one and note which makes the louder noise when broken. It takes almost no energy to break the toothpick so when you do break it there will be a very quiet pop because all of the energy put in to breaking it, very little, will be released. Now do the same with the plastic ruler and if it is brittle (not all are) it will require more of your energy to break it then it will take to break the toothpick. This time there will be a loud crack because of the greater energy expended by you to break it, all of which will be released upon breakage.

    The Hindu Kush earthquake would most likely have been induced by the continual northern movement of the Indian tectonic plate beneath the Eurasian tectonic plate.

  • Eugene F Kislyakov added an answer in Graphene:
    Why the adiabatic Born–Oppenheimer approximation (BOA) is broken down in graphene?

    I want to know is the broken down of BOA in graphene has been solved or not yet,

    See the link


    what are the other cases where the BOA is also broken down in them and Why

    Eugene F Kislyakov

    I also wonder, Sadeem.

  • Khaled Elnagar added an answer in ISO 17025:
    What is the new in ISO 17025:2015 for Laboratory Quality System either in managment or technical requirements?

    Are there major differences between ISO 17025:2015 issue and the old ones. Most laboratories having accreditation according to the old version afraid from these changes. Either testing or calibration laboratories. If we can raise these differences we will help all laboratories to make the required amendment smoothly.   

    Khaled Elnagar

    Thank you Dr Mushtaq

  • Peter Samuels added an answer in Reliability Analysis:
    Reliability Analysis SPSS: corrected item-total correlations above 0.7. Keep or throw out analysis?

    I am running a few reliability analyses on data regarding advertisements. The majority of the scales have items with corrected item-total correlations above 0.7. I was taught that items with item-total correlations above 0.7 are nearly measuring the entire scale itself. There is thus some redundancy.

    Although the scales are reliable (90%+ Cronbach's Alpha), the quality of the scales can be improved. Do I throw out those highly correlated items -to -total or do I keep them?

    Thank you.


    Peter Samuels

    Dear Jolien,

    i would advise you to run a principal component analysis on each scale a remove items with a loading on the first factor of less than 0.4. The size of the Cronbach's alpha needs to be interpreted in context and with respect to the number of items in your scale.

    Have a look at my article: https://www.researchgate.net/publication/280936182_Advice_on_Reliability_Analysis_with_Small_Samples?ev=prf_pub.

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Whilst it is common statistical advice not to attempt a reliability analysis with a sample size less than 300 a recent simulation study indicates that this is possible in certain circumstances. The most common statistic used in reliability analysis is Cronbach’s alpha and an often quoted rule of thumb is a coefficient value above 0.7 is acceptable for psychological constructs. However, some researchers assert that the size of a Cronbach’s alpha coefficient depends upon the number of items in the scale with scales with more items having higher coefficients. The advantage of carrying out a reliability analysis is that it can enable a researcher to treat a group of variables on the same subject as a single scale variable, reducing the complexity of further analysis and reducing the risk of Type I errors. However, student researchers often find it hard to obtain sample sizes of 300. The purpose of this worksheet is to advise students about how to go about trying to validate a scale with smaller sample sizes.
      Affiliation: Birmingham City University
  • Max Saito asked a question in Nanocapsules:
    Anyone knows a cationic polymer like Eudragit RS-100 for Nanocapsules, but biodegradable?

    I will start to work with nanocapsules and need to use a cationic polymer, like Eudragit-RS100. But, we will spray dry these nanocapsules to use in pulmonary route. As we know, Eudragit RS-100 is not a good candidate because it is not biodegradable and can be stored at the pulmonary branches. Anyone know a polymer like EUDRAGIT - RS100, but biodegradable? Thanks in advance.

  • Mercè Vilar added an answer in Music Education:
    Could anyone provide me with articles on music teacher education?

    Could you provide me articles on music teacher education?

    Mercè Vilar

    As Katrina McChesnye wrote, could you be more specific in your request? 

  • Enzo Pigueiras Aleaga asked a question in Mortar:
    Is there any bibliography about the uso of Powers Modell in mortars?

    I would like to know if there is any bibliography about the uso of Powers Modell in mortars. I am studying the uso of recycled aggregates in mortars and concretes.

  • Kazuharu Ohashi added an answer in Pollination Biology:
    What's the standard level of % seed set for self-incompatible, animal-pollinated flowers in natural conditions?

    I am looking for information on how much % seed set is the “standard” level for self-incompatible plants in natural conditions. Does anyone know useful references or compiled data sets etc. from which I can derive a quick answer to this?

    Kazuharu Ohashi

    Thank you Gad! What I wanted to know was simple: when I have ~80% average seed set in a population of self-incompatible species for one season, for example, I wonder whether it sounds reasonable to say that this species (in the particular population) was successfully pollinated during the season. I know this is a bit sloppy thinking, but I just wanted to know if there is any "common expectation" of % seed set among experts for self-incompatible species. Apparently not, as pointed out in everyone's comment. I guess that is what I needed to know, I appreciate it.

  • Anand Dev Gupta asked a question in Seawater Desalination:
    Seawater Desalination vs. Direct Potable Reuse?

    What are the ​key advantages ​and disadvantages ​of direct ​potable reuse ​as compared to ​seawater ​desalination ​for municipal ​water supply?

  • Michael Päch added an answer in Analytical Chemistry:
    How would someone explain several red-shifted Raman bands (assigned to N-H or C-N) with a strong increase in intensity?

    How would someone explain several red-shifted Raman bands (assigned to N-H or C-N) with a strong increase in intensity? It seems counter intuitive?

    Michael Päch

    You sure want to tell us about the sample under investigation, don't you?

  • Akram Abdul Cader added an answer in Islam:
    Could anybody provide me with articles about the impact of Islam or religious beliefs on ethical behaviour in the workplace?

    could any colleague provide me with articles about the impact of Islam or religious beliefs on ethical behaviour in the workplace?

    Akram Abdul Cader

    Hello Waleed, 

    There are quite a few comprehensive studies that you can look up. I recommend the following:

    Ali, A. J., & Al-Owaihan, A. (2008). Islamic work ethic: a critical review. Cross cultural management: An international Journal, 15(1), 5-19.

    Ahmad, M. S. (2011). Work ethics: an Islamic prospective. International Journal of Human Sciences, 8(1), 850-859.

    Rice, G. (1999). Islamic ethics and the implications for business. Journal of business ethics, 18(4), 345-358.

    Ali, A. J., & Weir, D. (2005). Islamic perspectives on management and organization.

    Ragab Rizk, R. (2008). Back to basics: an Islamic perspective on business and work ethics. Social Responsibility Journal, 4(1/2), 246-254.

    Owoyemi, M. Y. (2012). The concept of Islamic work ethic: An analysis of some salient points in the prophetic tradition. International Journal of Business and Social Science, 3(20).

  • Mario Radovan added an answer in Ethical Analysis:
    Which influential ethical theorists claim that inter-subjective attunement (sharing affective states with others) is necessary for morality/ethics?

    I'm looking for influential thinkers who argue that intersubjectivity is necessary for being moral and/or living a good life. Ideally I want to find examples of well-known analytic, continental, and feminist thinkers who hold this view. Thanks so much!

    Mario Radovan


    Your explanation seems correct. I am not an expert in ethical theories (I am a professor of information science). However, in some my texts I argue that the source of all our values and principles are feelings. I should probably add "and interests". But interest can be reduced to desires, which are feelings. I argue that reason is the engine, which knows no aim (end), and that feelings decide where the reason (engine) carries us.

    On the other hand, principles (rules) can be considered *conceptual expressions* that articulate (at the operative level) our feelings (interests, desires). For example, we can accept the Golden Rule because we wish *to be good towards others*, and also because we consider that it is in *the interest of our community* to behave in accordance with this rule. In fact, the Golden Rule was originally applied inside one tribe, not to the neighbouring ones.

    In sum, I do not have a relevant answer to the initial question. My position is that principles are expressions of our feelings (and interests), which are the source of everything we preach and do.

  • Dinkar Saxena added an answer in Heavy Metals Removal:
    What are the possibilities of using microbes for heavy metal removal from waste water?

    ​In the process ​we measured ​some of the ​factors like pH,​ temperature, ​electrical ​conductivity, ​concentration ​of iron and ​TOC and we ​found out that ​there is still ​heavy metal ​that is Iron (​Fe) in the ​treated water. ​The existing ​treatmnet ​procedures ​require a lot ​of expenditure ​to upgrade and ​modify.  I ​was reading ​that some of ​the microbes ​could do this ​job very easily.​ Can anyone ​guide me if we ​want to treat ​waste water ​containing iron,​ can microbes ​be used for ​this purpose? ​

    What are the ​different ​microbes to be ​used? I hear ​that F. ​thioxidans will ​remove Fe from ​waste water. ​Has anyone used ​this? Your ​experience much ​appreciated and ​will guide us. ​

    Dinkar Saxena

    Dear Amit,

    Please share the data of AAS



  • Dmitri Kireev added an answer in Pharmacophore Modeling:
    What can the best strategy for reverse pharmacophore modelling of protein-peptide complex?

    This question is regarding pharmacophore modelling or reverse pharmacophore modelling. I want to generate pharmacophore of a protein-peptide complex (basically a CRYSTAL COMPLEX ). Then I want to screen that pharmacophore against a ligand library to obtain some new lead molecules with a higher binding affinity than the original peptide. Please let me know what can be the best strategy/server/tool to do so?

    Dmitri Kireev

    In addition to already cited tools, Schrodinger's Maestro also features a comprehensive toolkit for pharmacophore modeling and database search.

  • Hiroyuki Wakiguchi added an answer in Egg Yolk:
    Egg Challenge

    Who can suggest me a protocol to reintroduce egg in a pediatric patient to verify if he has outgrown his allergy?

    Hiroyuki Wakiguchi

    U're welcome.
    No, I don't perform the test with raw egg basically.
    If the test result with hard-boiled egg is negative, I take time to increase heating egg intake gradually.
    Subsequently, if there are not symptoms at all and there are requests of raw egg intake with the patients and their families, I take time to lower the heating degree of egg gradually.

  • Shannon O'Sullivan added an answer in Ecotoxicology:
    How do I calculate a NOEC for ecotoxicology test?

    I need to calculate a NOEC, but i have 10% immobilisation in my control; will this effect my NOEC ?

    And how do i calculate it ? 

    Shannon O'Sullivan

    I assessed the effects over a shortened 2 hour period, the Issue im having is when drawing my graphs should I start the graoh from 10% immobilisation for the control or not ? 

  • Anand Dev Gupta asked a question in Effluents:
    What is the effect of oil on sand bed filtration?

    The ​filtration step ​forms part of ​effluent ​treatment and ​is designed to ​remove ​Magnesium ​hydroxide ​Mg(OH)2 ​colloids from a ​high pH ​effluent stream.​ The worry is ​that small ​amount of free ​oil entering ​the effluents ​upstream (eg ​due to leak ​from equipment) ​will affect ​filtration. Is ​anyone aware of ​industrial ​practice with ​similar issues? ​Is there ​threshold oil ​concentration? ​

  • Bendjedia Bachir asked a question in Automobile Engineering:
    WHat is the relation between the Hydrogen volume(or weight) and its tank weight for automobile applications ?

    hello dear colleagues,

    i want to know is there any relation between thé Hydrogen volume(or weight) and its tank weight for automobile applications ?

    many thanks

  • Giuseppe Cotellessa added an answer in Social Networks:
    What media sources do you trust most to be well informed on political matters?

    Do you trust some specific

    --Newspapers (web based or printed)

    --Radio or TV programs



    --Social networking sites.

    --Other Information Websites.


    Do you prefer a mix of these sources?

    Giuseppe Cotellessa

    Perhaps researchers will influence politics decisions by their positive invention in the future. My self note the low but constant diffusion of original my invention in all social media from Linkedin, Research Gate, Google, Academia Edu to Facebook and Twitter. It is essential in information diffusion success the proposal validity and making prototypes of invention.

    Best regards.

    Giuseppe Cotellessa

  • Haw Yen added an answer in SWAT:
    SWAT calibration problem, due to limited data.

    Hi, everyone.

    I am thinking of using ARC-SWAT to estimate outflow and sediment yield for catchment which covers area of 72km^2. All the required input data is affordable(DEM, landuse, soil type, weather etc).

    However, I found out that streamflow is not gauged in my target area, while plenty of waterquality data available(including suspended solids). 

    I can go out and measure the streamflow like twice a month but guess that's never enough to find out if model is valid. 

    Is there any chance of using the simulated data without calibration? or is there any hydrological model that does not require calibration?

    Thanks for your help in advance.

    Haw Yen

    In addition to the calibration of the whole time series (e.g., calibration of daily streamflow), you can also calibrate model outputs in the output.std file. In this case, you're calibrating annual summary of the targeted variables (such as Surface Runoff Q) so that you don't really worry much about the temporal data. It may not be the perfect way to conduct calibration but it may help a lot in many cases. 

  • Tri Bui asked a question in Photosynthesis:
    Coix aquatica photosynthesis with C4 or C3 pathway?

    Anyone can give me the answer that whether Coix aquatica is photosynthesizing with C4 or C3 pathway? (for me, it look quite like a typical C4???)

    I just start being interested in this amazing grass. Give me some advices if you having similar interest.

  • Biswajyoti Mukherjee asked a question in Alumina:
    What happens when we heat pure aluminum?

    What happens when we heat pure aluminum near its melting point(663oC) in atmosphere(no vacuum or nitrogen)? Does whole of the sample transforms into oxide?

    I have come across a paper where aluminum was heat treated near its melting point in open atmosphere and still showed no alumina peaks in xrd.

  • Lorenzo Fiamma added an answer in Educational Games:
    What do you think about educational games developed in Virtual Worlds like OpenSimulator?

    Does this tool satisfactory to be used for this purpose?

    Lorenzo Fiamma

    I'm very interested to see how virtual reality could be used as an environemnt to simulate dangerous situations like an accident scene or a civil construction environment. With modern technologies users' presence and agency can be enhanced drammatically. Also augmented reality can play an important role, if you want to recreate a dangerous situation by inducing the perceptional and cognitive reaction of students by projecting them into an immersive learning environment. 

  • Rubén Martínez Vidal added an answer in Satellite Communication:
    Could we treat a satellite communication system as a DTN?

    For mobile satellite communication system, Such as Iridium system in which every satellite could establish four links with its neighbor, can it be regarded as a DTN? And, if we could design the satellite constellation in term of DTN, could it reduce the cost of satellite networking and make the satellite Internet be popular?

    Rubén Martínez Vidal

    I wouldn't personally regard it as a DTN (Delay and Disruption Tolerant Network).

    Using the analogy comparing a satellite constellation to a wireless network. From a connectivity (disruption) perspective: a quick glance to a graphical depiction of the Iridium constellation shows a mostly connected network. Additionally, your assumption of an average node degree of 4 (neighbours per node) is much more on the line of usual MANET scenarios. I think that this network would be too heavily populated to display frequent end-to-end path disruptions. 

    From a delay perspective, the one-hop communication delay would be bigger than common networks (due to the increased distances) but not that big, and the resulting latencies can be easily addressed using a TCP flavour such as CUBIC or Hybla. The end-to-end delay would be influenced by the idle time on the buffers of each intermediate node, which would be mostly determined by the disruptions along the path to the destination (as I assumed before: not frequent) and therefore resulting in low delay (for DTN standards).

    All of this is purely speculative and It really depends on the specific characteristics of your scenario: node mobility patterns, communication ranges, and so on.

    You should spend some time characterizing your scenario before trying to address the problem with a specific network paradigm (be it DTN, MANET, etc).

  • Anand Singh added an answer in Antenna Design:
    Does anyone know about antenna efficiency?

    I have designing microstrip patch antenna and was getting gain and directivity as around 9.5 dB and 8.7 dB approx.But I was getting the value of efficiency in negative.

    Can you please clear this confusion.

    Thank you.

    Anand Singh

    But what I am getting according to the simulations is different. So which one is right?

    Kindly see the images in my previous answer.

    Thank you.

  • Yang Su added an answer in Microfluidics:
    How do I remove large droplets when preparing oil-in-water nanoemulsion? What kind of filter or membrane filter should be used?

    When preparing nanoemulsion with microfluidizer, we usually let coarse emulsion pass through the interaction chamber of the microfluidizer repeatedly until the desired particle size is obtained. After this, the bulk emulsion will be filtered through a filter under nitrogen to remove large droplets. Without the filtration, it is very hard to satisfy the regulatory requirement of the number of large droplets per mililiter . 

    My question is what kind of filter or membrane filter should be used when preparing oil-in-water nanoemulsion?

    Yang Su

    What is your definition of "large droplets"? Using a Microfluidizer is exactly on the opposite side of what you are trying to do. The major advantage of using Microfluidizers is to produce nanoemulsions with very small particle size and narrow size distribution so there will be no "large droplets". Depending on your definition of large droplet, If you can't get rid of them, the first thing I would suggest is to optimize your formulation and process parameters such as pressure, temperature, selection of interaction chambers, and number of passes, etc.

    Now, if you are doing sterile filtrations, which is very common for many pharmaceutical applications such as injectables, you would want to monitor the particle size of D90 or D95 measured by a laser diffraction instrument. The reason is sterile filtration uses a 0.2 micron rated filter, therefore measured D90 or D95 are good indications of whether the nanoemulsion will clog the filters. The average particle size such as Z average won't tell you this piece of information. Microfluidized nanoemulsions should pass through this size of filters very easily. I should also point out that the membrane material is also very important and formulation dependent.

    Let me know if you have further questions and I will be happy to help you.

  • Simon Welham added an answer in Mesonephros:
    How can I get adult zebrafish mesonephros to stay flat after its been dissected out for wax embedding?

    I can dissect out adult mesonephros from zebrafish but I need them to stay flat and not fold up so I can embedd them in wax and get a good plane of section when cutting. Its important that I get a section equivalent to what it looks like pre cutting.

    Simon Welham

    Can you manipulate it in agarose? Should set in desired orientation.


  • Mårten Söderberg added an answer in Pulmonary Embolism:
    What is the most reliable marker in the differential diagnosis of pulmonary embolism and community-acquired pneumonia?

    Because of similar clinical manifestations and laboratory findings, differential diagnosis of pulmonary embolism and community-acquired pneumonia (CAP) is generally difficult. 

    Mårten Söderberg

    We have shown (See attached file) that the symptoms in CAP differ from those in PE in that aspect that CAP patients more ofte have fever and chills when the fell ill, and thereafter develop dyspnoea,  whereas PE patients more often start with dyspnoea an pleuritic chest pain and after that sometimes develop fever. You can not reliably trust CRP, temperature, D-dimer nor chest X-ray. 

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: To compare initial symptoms in pulmonary embolism with community-acquired pneumonia and relate to C-reactive protein and pulmonary infiltrates in order to improve the clinical assessment at the emergency department. A retrospective review of patients with pulmonary embolism diagnosed in the clinic for infectious diseases (CID), (n=25), and a randomized sample of patients with pulmonary embolism diagnosed in the department of medicine (n=64), and a randomized sample of patients with community-acquired pneumonia (n=54) diagnosed in the clinic for infectious diseases. Initial symptoms in pulmonary embolism, dominated by dyspnoea and/or pleuritic chest pain were significantly different from those in community-acquired pneumonia, dominated by fever, chills and/or cough (P<0.001). On admission, C-reactive protein and body temperature were significantly higher and pulmonary infiltrates were more common in pneumonia compared with randomized pulmonary embolism patients. Twenty-five patients with a final diagnosis of pulmonary embolism were erroneously suspected of having lung infection, owing to increased C-reactive protein, presence of pulmonary infiltrates and/or high fever. However, they had classical symptoms of pulmonary embolism. Pulmonary infiltrates, high fever and a high level of C-reactive protein can deceive the physician to suspect pneumonia instead of pulmonary embolism. Classical initial symptoms ought to direct the physician in diagnosing pulmonary embolism. We emphasize a detailed patient history of initial symptoms.
      European Journal of Emergency Medicine 09/2006; 13(4):225-9. DOI:10.1097/01.mej.0000217980.69459.80
  • Jacques Lavau added an answer in Electromagnetic Waves:
    How do you visualize a photon?

    I am writing a paper for a conference titled: The Nature of Light: What are Photons? It would be very helpful to obtain an idea about how this group of scientists visualize a photon propagating in a vacuum. There are no right or wrong answers. You can give either a detailed answer or merely choose one of the following four photon descriptions. A) The Copenhagen interpretation where a packet of energy discontinuously jumps to form waves of probability. B) The de Broglie model where a packet of energy has a pilot wave which steers the packet of energy. C) A distributed electromagnetic wave which propagates in an empty vacuum. The particle property appears because the energy collapses to a point when absorbed. D) A distributed electromagnetic wave propagating like a quantized transverse sound wave in the quantum mechanical medium of highly energetic vacuum (zero point energy). The particle property appears because the energy collapses to a point when absorbed.

    Jacques Lavau

     The distance from emitter to the absorber is 2a in my notation. z is the maximum radius of the spindle ; 2z is the diameter.

    The second essential parameter is the wavelength \lambda. For massive particles it is merely the de Broglie's one : h/(mv), where v is the group velocity.

    Each time the particle interfers with itself, the de Broglie's frequencies and wavelengths are those to consider. When the interaction is electromagnetic, and with something else, as for the Compton's scattering of photon on a free electron, use the Dirac-Schrödinger frequencies 2mc²/h and wavelengths h/(2mv) instead. Schrödinger discovered that in 1932, and I rediscovered it in 2011.


    And Richard Feynman ignored it in all times...

    All the notations above are for non-relativistic speeds, and unbound electrons (or neutrons).

  • Nisarg Patel added an answer in HFSS:
    Any suggestions for a plasma antenna in CST or HFSS?

    I want to design a PLASMA antenna for microwave frequency. Is there any manual i can find about it. Please do let me know

    Nisarg Patel

    Below link may be useful to you,