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  • Ljubomir Jacić added an answer in Fluctuations:
    Could you please tell your point of view on the current situation worldwide ?

    Is it a stable or fluctuating and we are faced to the glabal danger

    Ljubomir Jacić

    Turkey’s explanations of incident with Su-24 is the Theatre of the Absurd - Peskov!

    "Turkey’s reactions to the incident with the Russian Sukhoi Su-24M, downed by the Turkish Air Force above Syria, reminds of the Theatre of the Absurd, Russia’s presidential press secretary Dmitry Peskov said in an interview with the Vesti V Subbotu (News on Saturday) television programme.

    "The president of Turkey has made a statement, where he said if a Turkish jet is downed above Syria, he would consider it an act of aggression," he said. "Then, how to qualify what has happened with the Russian jet?"

    "Look, it is a sort of the Theatre of the Absurd," the press secretary said."

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  • Syed Abbas Jafar added an answer in Climate Change:
    Are there authentic published work confidently pinpointing the sole anthropogenic factors contributing to Climate Change?

    Combined natural and anthropogenic factors (geologically recent phenomenon) govern Climate Change. It is, therefore, of paramount importance to discretely recognize the role of humans in Climate Change and to plan efficient strategy to mitigate it.

    Syed Abbas Jafar


    Thanks for your answer but I am waiting to hear from Peter as well. One has to go through all the answers of this Question to understand the problems and the reasons for us being skeptical about the core conclusions of IPCC.



  • Nabil Belgasmi added an answer in Regression:
    Genetic Algorithms outperform Artificial Neural Networks ???

    Can Genetic Algorithms (or GP) outperform Artificial Neural Networks?

    ANNs try build a "complex" mathematical function that best fits a given input to an output. This principle was used largely to solve a wide range of problems: classification, prediction, clustering, etc.

    GP (and GAs) proved their abilities in building complex functions (symbolic regression, non-linear regression, etc.) that maps (input, output).


    Is it possible to make GA (or GP) outperform ANNs (or at least behave exactly as) GAs (or GP algorithms)?


    If GAs > ANNs - forget about No Free Launch Theorem for the moment:)  so why GAs are not too "reputed" in such domains?


    What is done by ANNs and cannot be done with GAs or GP based algorithms?

    Nabil Belgasmi

    For me, GP should be more efficient than ANN whatever its architecture.

    The problem is essentially in the Learning Strategy used in GP !

    That's why they are actually a little bit "wilder" than ANN.

  • Emad Abu-Shanab added an answer in Refugees:
    What are the ethical issues of RFID?

    I am doing a research regarding the ethical issues of RFID on employees or refugees. After what happened in France, it seems that governments are thinking of using bracelets to track refugees in their countries or wanted people. The same in case of employees... I read few articles and found few ideas, but I would benefit from your experience.

    Emad Abu-Shanab

    I guess all agree that it is not human and would vote against it. I guess some visited the need to such technology and approach (aims justify means). Still we see tracking and privacy as major issues here... 

  • Cornelius Atere asked a question in Sodium Iodide:
    Dear all, can someone guide me on the preparation of sodium iodide (NaI) solution with density of 1.7 g/cm3 from the salt having density of 3.67g/cm3?

    Dear all, can someone guide me on the preparation of sodium iodide (NaI) solution with density of 1.7 g/cm3 from the salt having density of 3.67g/cm3?

  • Natalia Teles added an answer in Salts:
    What is the better way to prepare salt solutions RNAse free; due reactions between depc and salts? Can I add depc in the solution and autoclave later?

    Prepare salt solutions, add depc and autoclave later? Or prepare solution with already depc-treated water and autoclave to sterilize ? Or prepare solutions with depc treated water and filter them?

    Natalia Teles

    Ok. Thank you for help.

  • Hala Hazzaa added an answer in Chromosome 22:
    What is the most suitable Dental Mangement in The 22q11.2 Deletion Syndrome?

    A 22q11.2 distal deletion is a rare genetic condition caused by a tiny missing part of one of the body’s 46 chromosomes – chromosome 22.

    What is Dental  Mangement in The 22q11.2 Deletion Syndrome?

    Hala Hazzaa

    Hi dear, concerning these patients .. I think that the dentist should pay attention to 3 main defective items; 1) The systemic management should be carefully handelled owing to the cardiac, renal, as well as endocrinal disorders that mostly are present in these cases. 2) The defective immune response that may raise the risk of infection spread, and need proper antibiotic treatment & prophylaxis 3) The dental treatment, in that regard, the clinician should determine the defective part & the degree of affection using the proper diagnostic & radiographic tools then, proper treatment plan is applied. Treatment plans for these patients may be complicated and need teamworks of orthodontics, maxillofacial surgeons, radiologists, prosthetic, periodontists,...

  • Mahsa Jahani added an answer in Foam:
    Can someone help me to find a viscoelastic foam with high strength?


    I'm attemping to use a viscoelastic foam as an energy absorber. Can someone help me to find a viscoelastic foam with high strength?

    Mahsa Jahani

    I need some more suggestion to compare and make a correct decision, help me please. Note that strength is one of most important parameter in this study.

  • Mohamed El Naschie added an answer in Special Relativity:
    Can someone re-write the Einstein field equations in such a way that c becomes a global constant?

    I recently showed that the equivalence principle observes this constraint. This fact is trivial because the equivalence principle is based on special relativity alone.

    Therefore, the full field equations must be capable of being re-written in this form. Otherwise, the equivalence principle would no longer fit in.

    So the proposed transform sought is the so far missed "physically correct version" of the Einstein field equations.

    Mohamed El Naschie


  • Abdulelah Ahmed Thabet added an answer in Polyphenols:
    What is the suitable Column for Polyphenol Fractions by HPLC or other techniques?

    I have crude plant extracts of which were separated  5  polyphenols I have to separate and purify these 5 fractions (cynarin,chlorogenic acid,1,3-Dicaffeoylquinic acid,and cynaroside).

    Abdulelah Ahmed Thabet

    Dear all thanks for your response.

  • Sibasish Dutta asked a question in Stock Solution:
    What is lowest amount of BSA protein that can be conjugated with citrate capped gold nanoparticles (20 nm)?

    What is lowest amount of BSA protein that can be conjugated with citrate capped gold nanoparticles (20 nm) through direct binding (without using any linker)?I have prepared BSA stock solution of 0.1 mg/mL to 0.3 mg/mL (in water) and mixed them one by one at a ratio of 1:3 (BSA : AuNPs colloids) and found that the below 0.1 mg/mL conjugation, no shift in plasmon resonance wavelength (of AuNP) observed below 0.1 mg/mL? 

    I just want to know that is below 0.1 mg/mL conjugation and detection using spectrophotometer possible or not?

  • Mark Keiter added an answer in Earth Sciences:
    What is the weakest thing about uncertainty theories and algorithms in geology?

    I believe that uncertainty assessment approaches are not well-developed in earth-sciences. Do you consider it as a deficiency?? If yes, do you have any solution for any case? We can discuss and work on it together. :-)

  • Rami Sawahreh added an answer in Orphenadrine:
    How we do optical resolution of Orphenadrine drug ?

    orphenadrine optical resolution

    Rami Sawahreh

    Thank You Rafik 

  • Adriana Torres-Mansilla asked a question in 2D & 3D:
    A sample composed of a film homogeneously mineralized with HAp, what type of nanomaterial could be considered? as a 0D, 2D or 3D ?

    I'm reading about mineralization with SBF in different kind of films, but i'm not sure if the resulting material ( an homogeneously HAp mineralized film) could be a 0D, 1, 2 or 3 dimension material. Thank you!

  • Rahimah Haji Ahmad added an answer in Transformational Leadership:
    What is the best measure for transformational leadership?

    What is the best measure for transformational leadership?

    Rahimah Haji Ahmad

    My personal view is that leadership itself cannot be accurately measured - it depends on the organization  the "leader" works in or the people he/she works with. Measues of success then the "success" of the organization or group in achieving what is desired (ythe objectives or mission). Hence transformational leadership is then measured with the level of cooperation the leaders gets in the grouo and collegiality achieved - meaning the "leader" can 'transform' the group to be cohesively working towards its goal - which in itself should be innovative, creatinve - ie transformational - be it in the ways in getting things done, as well as success it getting things done in creative ways.   

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub

    Erkki: "... jumping directly to brain based theories seemingly avoiding the hard problem."

    A vast body of evidence points to the activity of the brain as the source of conscious experience. Why do you claim that exploring brain-based theories is avoiding the hard problem?

  • Stam Nicolis added an answer in Quantum Gravity:
    Is there any theory of quantum gravity which is fully constructive, i.e. explains curved space-time?

    Does any current candidate theory of quantum gravity aim to, or claim to, construct or explain the curvature of space-time?

    My understanding is that quantum gravity theories are classified as background dependent or independent, according to whether they are formulated such that the depend on the shape of space-time or not.  This is *not* what I am asking.  I am asking whether they give an account of the cause of curvature of space-time.

    Stam Nicolis

    No the conclusion does not follow and it's known. The last paragraph contains false statements. That spacetime is continuous is perfectly compatible with four-dimensional diffeomorphism invariance and with interactions, described by quantum fields, that do not conserve particle number. That quantum fields may not create and annihilate point-like objects, but, rather, extended objects is a possibility that's being explored, when gravitational fluctuations become comparable to quantum fluctuations. 

  • Elaf Samir added an answer in XPS:
    Can I do a XPS depth profile for a a 500 Micrometer thick sample?

    I have a 500 Micrometer thick sample and I would like to do a depth profile by XPS is it possible for such a thickness ?

    Elaf Samir

    Thank you all for your helpful answers and suggestions . The 500 Micron thick metal thick substrate has a carbon diffuse in so I would like to see how the carbon diffuse from surface to surface .I've tried using EDX but it is not accurate because the contamination from the pump (carbon come from the pump oil). Moreover I'm not quite sure if few nanometre XPS etching depth profile is enough to give an indication for the diffusion manner of carbon inside the substrate. I will try using the Angle resolved XPS depth profile and I have no idea how accurate it is ?. If any one have please back to me.
    Thanks all

  • Muhammad Shahid added an answer in Meteorology:
    How do I select representative rainfall for a catchment having elevation difference?

    I am doing a study on small dam which have catchment area of 152 km 2. There is only one meteorological station installed in catchment area. There are two other meteorological stations which are near the Dam site but not in Dam catchment. The elevation of Dam is 570 meters. The only one Meteorological station which is within catchment area have elevation 2170 meters. The other two Meteorological stations which are near dam have elevation 543 meters and 517 meters. As the catchment have elevation difference ranging between 570 meters to 2170 meters. How I can find the actual rainfall of catchment.

    Muhammad Shahid

    I am much thankful for all researchers guidance. Can any one share a paper in which catchment rainfall data is obtained by averaging two of the stations??

  • Peter Donald Griffiths added an answer in Quality of Health Care:
    How do I measure the quality of health care in hospitals?

    Many of the avialble studies on patients satisfaction with health care in hospitals do not reflect the correct picture! mostly overestimate the quality. 

    When we study the health care quality in hospitlas, what dimension should we include? whom to ask {Which sample, what characteristics}? to study QoC in qualitative or Quantitative approach?

    Peter Donald Griffiths

    This is a huge question and a huge field...there is lots of literature out there but can I offer two frameworks to start thing about it:

    The classic Donabedian "Structure-Process-Outcome" (which identifies multiple aspects of quality and potential points of measurement. In the UK over recent years the NHS has often arrived at a formulation that divides quality over the dimensions of: experience, effectiveness and safety.  There are other ways of looking at it, but a matrix based on these two frameworks will quickly demonstrate that quality is multi-dimensional and needs to be measured and treated in that way. Patient satisfaction / experience is important, but it can't be taken in isolation. At a system level equity and access should also be considered.

    I realise that I haven't really answered your questions about sample, but until you have determined dimensions to be assessed and specific indicators associated with these indicators you can't really adress sample. 

  • Jochen Wilhelm added an answer in Microsoft Office Excel:
    How good is my data should I test for normality

    Firstly I'm definitely no statistician so be gentle with me.

    I Have 17 data sets from likert scale questions with possible answers of 1,2,3 and 4. I have this for 70 different questions from the 17 participants

    I would like to assess how good my data is. I think the best thing to do would be to assess normality

    I have tried a calculation i found in excel and using spss and the Shapiro-Wilk test

    The excel normaility test suggests a lot of my data sets (ie data from each question) have some degree of normality but the Shapiro-Wilk not so much.

    The problem is when looking at the histograms and normal Q -Q plots they look fairly normally distributed to me. for example the following data set


    question is should I bother at all and if so am i doing it right?

    Jochen Wilhelm

    Hi Jamie,

    don't be afraid for not beeing a statistician ;) No one will harm you. We all meet here to help and to learn from each other.*

    The quality of data has nothing to do with the frequency distribution of the values in your data set. The quality is rather related to procedure how the data was obtained, and if or how well the data containes information that is relevant to the aspect you want to study.

    A test on normality (like Shapiro-Wilk) is a tool to select data sets that -for some reason- deviate somehow considerably from a normal distribution. Such tests may be used to identify data sets for which it seems to be promising to further investigate the reasons for this deviation, what implies that you assumed that these data sets actually should be approximately normal distributed. It is NOT suited to "negatively" identify data sets, that is, to identify those sets that are approximately normal distributed.

    However, your problem here is at a much lower level: you misinterpret the information content of your data. The data you have is ordinal. It is as ordinal as the letters in the alphabet: you can say that A comes before B, but there is no meaningful difference between A and B, nor is there a meaningful sum of A and B. It is as nonsensical as impossible to calculate a mean or a standard deviation or any other statistic based on sums and differences for letters! Your problem is that you coded the different values from the Likert scale with arabic numerals ("1","2","3","4") and that this seems to tell you that you could use these data as if these actually were intergers (which are interval scaled). But these "numbers" you used are only labels, these are NO NUMERIC VALUES. It would be really better to code the values with letters, like A,B,C,D. Then you can think what kind of information these data can contain and how you can make use of it.

    The normal distribution is thus a very unreasonable or nonsensical distribution model. The appropriate distribution model is the multinominal distribution.

    You should use methods for the analysis of ordinal data. Ordered logistic models may be appropritae, but their results are not easy to understand. Testing simpler but meaningful hypotheses on ordinal data may require bootstrap techniques. This paper (dealing with vconcentration measures for ordinal date) may be interesting for you: http://meetings.sis-statistica.org/index.php/ginilegacy/SIS2015/paper/viewFile/3511/696


    *But I nevertheless like to urge you to learn statistics, to understand the basic principles related to experimental design, data, information, and the formalization of "knowledge" - because all this is the very fundament of any empirical research. You will only be chased by your data and by opaque opinions of others, you will have to rely on interpretations and conclusions that you won't be able to scrutinize. That would be a very sad existence as empirical scientist. I advice you to see statistics not as some unfortunately neccessary tool to get your results published but rather as a help to get a better understanding of (your) data and to better judge the adequacy and sensibility of methods, statements, interpretations and conclusions you read in books and papers. This implies that using some statistical methods like a cook-book recipe is not getting you there. Try to learn and understand what these things are: data, information, entropy, probability. You will find a lot in the internet and you will be astonished how exiting this can be and how fundamental this all is to your work as an empirical scientist. Then you can go on and try to learn the technical meanings of some important concepts like statistical model, assumption, statistical hypothesis, likelihood, Fisher information so that you will be able to understand the concept of estimation, standard errors, p-values and confidence intervals. You will likely NOT learn this in any statistics course or from some "easy-to-read" or "easy-ton-understand" book on statistics. These are almost all sources of mere cookbook recipes for conducting some statistical analysis and usually are not at all helpful to really understand the underlying concepts. Even worst: most of these sources are based on a quite flawed understanding of probability, using circular definitions already in the very introduction of the topic. This inevitably leads to severe logical problems and inconsitencies later on. And to my deep conviction the main reason why students do not understand (or are even scared of) statistics is because they tried to make sense of these flawed explanations (what must fail). So my advice is to use your brain, a good bit of common sense and the internet and start searching for definitions of the most basic words related to statistics, like "data", "information", and, for sure, "probability". Read critically what you find and build your picture.

  • Ossama Mohamed Zakaria added an answer in Descriptive studies:
    What checklists can I use to assess my cross-sectional and descriptive study for quantitative data except CASP checklist for quantitative study?

    What checklists can I use to assess my cross-sectional and descriptive study for quantitative data except CASP checklist for quantitative study?

    Ossama Mohamed Zakaria

     Dear  Karami it is me not Benhnam who suggested STROBE 

  • Krupa Mysore added an answer in Flow Cytometry:
    Unspecific stimulation with PMA + ionomycin vs. PHA for intracellular cytokine staining of T cells
    I am trying to compare cytokine production (gamma interferon and TNF alpha) by T cells in different patient populations, looking for functionality versus exhaustion. As I do not have a specific antigen available, I am stimulating the T cells with PHA or with PMA + ionomycin before Golgi stop. However, these two protocols give qualitatively different results for the comparison of my populations. Can anybody advise me which stimulation protocol is more suitable and significant, and what is the difference between the cells activated by these two stimulants?
    Krupa Mysore

    Thanks Maria! The problem that I am having is that after 6 hr stimulation with anti CD3/

  • Paul Reed Hepperly added an answer in Soil:
    What are the soil properties sensitive enough to differenciate soils of organic and conventional farms?

    soil microbilogist

    Soil Scientist

    Soil Physicist

    Paul Reed Hepperly

    Dear Dr Rao Labile organic matter is extremely important for the mineralization of nutrients that nourish and support of beneficial soil microbes. When the use of organic amendment, cover, and rotations are combined with no till the labile portion which is measured by permanganate test. Liber organic matter responds quickly within a season to our biological practices such as organic amendment and cover crop. . Toxicants work against this transformation in the soil biogeochemistry. 

    When the integrated biological practices are maintained the passive organic shows a more delayed and muted response compared to labile organic matter. Any decrease in crop potential for withdrawing of synthetic inputs can be eliminated by 3 years of biological systems implementations. We call this the organic transition period. The biological activity is not positively influenced by synthetic inputs.

    As labile organic  increases are sustained the inevitable response is an increase in soil organic matter. In a statistical sense this takes years. Since the relative increase of a percent per year from the soil baseline is not discernible from early year field sampling since field variation is relatively large for a small effect. Yet after 1 or 2 decades the Soil Organic Content which is largely passive Organic matter is manifested. Because this is unseen it almost takes faith but it is real if you have the time and patience to to do the work. 

    As methods are used such as ensuring the mineral status and pH and Calcium content of the soil. Most work in this area have not followed the responses long enough to detect the changes that are slowly occurring in the passive pool of organic matter. Allow the labile organic matter is a measure of soil metabolic capacity it is  the passive organic that is very important for water relations through its effect of soil aggregation and the ability of the soil medium to provide air and water needed by optimized root systems.  

    When labile and passive reserves in the soil increase the enzymatic capacity will increase in turn. The measurement of Carbon dioxide generation is a good indication of the total soil biological activity these parameters are allow correlated. 

    When people originally looked at supporting the soil system they hypothesized that if crop biomass was optimized the system would not degenerate but because in many of these systems the high productivity of the crop also stimulates a high decomposition rate the system itself is not fully sustainable.  Irony is while the immediate effect of the input system are large and visible and apparently positive their long term effect is the increments of small annual decreases which after a generation or two unveil a lack of support without anyone even noticing it. 

    In fact while the native biomes all supported over 5% soil organic matter in conventional monocultures of row crops it would be difficult to find many close to 5% with 1 or 2% soil organic matter being our new commonplace. Through the biologically based systems developed at the Rodale Institute it is proven that this goal of 5% soil organic matter is indeed possible in cropping systems featuring a withdrawl of synthetic inputs and an emphasis on cover cropping and organic amendments. Organic amendments make the transition occur more rapidly but it can be done completely by the use of native plant inputs. 

    Enclosed take a look at how the continued small incrementable increases actually increase the yield potential compared to conventional input systems under favorable yield environments in the field after the transition and improvement through the continuing practice. I include the active experiment which now has over 33 years of the side by side comparison is randomized replication large field plots. 

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  • Somayeh Zangeneh asked a question in Mammals:
    How is the fanctional biology of intestinal gablet cells in aqutic?

    How distribution, Type of activity and its value, Appearance, The difference with mammals

  • Pengfei Wang asked a question in LIBS:
    Can LIBS gives the information of the defects in glasses, such as BOHC, DOC in SiO2?

    Can LIBS gives the information of the defects in glasses, such as BOHC, DOC in SiO2?

  • Peter Donald Griffiths added an answer in Diabetes Management:
    What is the proportion of diabetes patients with good or optimal quality care?

    I have seen many articles discussing quality of care among diabetes, either using the process of care, chronic care model or any other models of care, but not of the articles categorical stated that the proportion with good or optimum quality of care

    Peter Donald Griffiths

    Johnson. The UK general practice "Quality and Outcomes Framework" (QoF) is a pay for performance system that gives funding to genreal practices in the UK depending on how they perform for people with a range of conditions. It includes both process (e.g. blood pressure checks) and outcome measures (e.g. HcA1c below a given threshold). While the QoF for diabetes may not define 'optimal' care data buplished using it might give you some insights: a google scholar search: "quality outcomes framework uk diabetes" gets you into this literature. We've used data on HbA1C control in a recent publication which might be of some(indirect) use....

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  • Peter Kevan added an answer in Dinosaurs:
    Did plant-eating dinosaurs evolve a system for dealing with the toxicity of cycads, a widespread plant group during the Mesozoic?

    The plant-eating dinosaurs over the time they existed should have developed a system for dealing with a readily available plant source,that was toxic i.e. the cycads.

    Peter Kevan

    Fascinating question!  I seem to remember, dredging memory, that an eminent entomologists from the University of Bristol (whose name I am unable to recall) suggested that angiosperm flowers were warning colours to herbivorous ceratopsian reptiles. Folowing from that thread comes the roles of the flamboyant reproductive structures of some Bennititales being more than for pollen movement.  

    Modern (and ancient cycads?) contain various secondary compounds, poisonous fruits (for some possible consumers), lots of phenols, and are immensely tough and fibrous. Such features would deter many kinds of herbivores.  Those that could ingest and digest cycad vegetation would presumably have had a suite of character to allow for that, including detoxification systems (enzymes and gut symbionts), complex  guts with caeca (as in many modern birds), continually growing teeth, and powerful jaws.

    Thank you for the question.


    Peter Kevan 

  • Alexander T. Morchenko added an answer in Hall Effect:
    What type of sensors can be used to analyze a magnetic flux density on a surface of a sample?

    I am planing to analyze magnetic flux density on a surface of samples. The material will be low alloyed steel with a ferritic microstructure. The range of the magneitc flux density will be lower than 0.2 mT. So far, I used Hall effect sensors. What other sensors can you suggest?

    Alexander T. Morchenko

    You can try the local sensors of magnetic fields on the basis of the off-diagonal magnetoimpedance in ferromagnetic microwires (equivalent of a magnetoresistive, but more sensitive). And in addition to sensors, perhaps, it may be suit the techniques magnetic-force microscopy and Lorentz electron microscopy (for small samples), powder figures, the magneto-optical Kerr ellipsometry or stray field topography with magneto-optical transparent films (magnetic garnets with high Faraday rotation).

  • THOMAS H.W. Ziesemer added an answer in FDI:
    The Heckscher-Ohlin theory is preferred to the Ricardo theory by economists because it makes fewer simplifying assumptions. What is your view?
    THOMAS H.W. Ziesemer
    • I f factor endowments are sufficiently much different between countries in HO theory, there will be perfect specialization and no factor price equalization. The country with the lower relative labour endowment will have higher wages. The zero profit situation indicates the struggle. Both models are just first principles. The competition and innovation issues are much clearer in the combination with endogenous growth. See Grossman/Helpman book 1991 or the articles.