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  • Ni Ge added an answer in de Broglie-Bohm theory:
    How can we interpret Hafele-Keating experiment with De Broglie-Bohm theory?

    Without refering to theories which tried to merge Special Relativity with De Broglie-Bohm theory, can we explain a shifted time mesurement with De Broglie-Bohm theory only?

    Ni Ge

    Actually the pilot wave doesn't elongate. There is only a time dilation which seems to elongate the wave.

    To conclude:

    0. Hafele-Keating experiment (and a prefered frame) proves that SYMMETRY of LT doesn't work anymore.

    1. A change of frequency seems not to be adequate, because it would involves a light speed greater than c.

    2. Following a thought experiment of an unwinding coil, there can't be length contractions.

    Try to unwind a coil (How many tours? At which speed?) and explain me how the thread can be contracted for the moving observer and not for the ground observer where both see 1m?


    But with time dilation only it works.

    3. There is a time dilation, but velocity and time act in a same way (where time factor is twice the velocity compared to a static observer). So space-time can be flat.

    Then nothing contradicts QM and some new transformations in SR should be done with those remarks.

  • Anna Kretzschmar added an answer in Scientific Editing:
    Any ideas rendering text from LaTex to Microsoft Word ?

    My literature review is written in LaTex and the references are in BibTex - however I frequently need to send documents to my supervisor in Microsoft Word. So far I have rendered the LaTex document into pdf and then back into Word, but it plays havoc with the formatting.

    Does anyone know of a program/writing language that can render text written in LaTex reliably into .doc file?

    Anna Kretzschmar · University of Technology Sydney

    I'm going to give tex4ht a shot before going to the paid version. Options = hope that I don't have to convert everything so thank you very much for your help! and the tutorial link.

  • Rouhallah Sharifi added an answer in PGPR:
    Can anyone explain and interpret how PGPR traits contribute wild plant's survival under arid conditions?
    PGPR Rhizospheric Soil status allows plants to grow and be healthy. Especially in regards to a plant's "adaptation to arid environments".
    Rouhallah Sharifi · Razi University

    induction of systemic tolerance in plants seems to be important. I suggest a comprehensive review article in this case.


  • Ajinkya Nene added an answer in Spin Coating:
    Can I do doping of nanoparticles on sheet by using spin coating or drop casting

    spin coating or drop casting

    Ajinkya Nene · Chubu University

    Sir, its about deposition of nanoparticles on substrate. But the deposition should be in such a manner so that substrate properties should get enhanced because of nanoparticles.I mean conducting properties. Please guide me.

  • Stephen Cheung added an answer in Risk Assessment:
    What do you think about Kinney-Wiruth risk assessment method?

    Risk assessments are vital support to decision-making process. Risk assessment supports the design review process by providing the underlying analysis on which safety decisions can be made. Risk assessment methods are being deployed in many industries, and the momentum is likely to continue. Although the level of sophistication in risk assessment processes varies the general risk assessment process applies both across and within all industries.The Kinney method was first introduced in USA, being proposed by G.F. Kinney and A.D. Wiruth in a technical document of Naval Weapons Center in California, see (Kinney and Wiruth, 1976). Initially aimed at explosion risk prevention in military industry, the method was rapidly adopted in Europe, with immediate success. I am interested in knowing what happens nowadays with this method, is it in use and does anyone have examples of its use.

    Stephen Cheung · Azusa Pacific University

    I came across this article:

    Managing Risks: A New Framework by Robert S. Kaplan and Anette Mikes.

  • Afzal Muhammad Tanveer added an answer in Development Studies:
    What are the differences between regression model and econometric model?
    Data cleaning is required in the econometric model.
    Afzal Muhammad Tanveer · Allama Iqbal Open University

    Yes the coefficient and the multiples matters, but before going to the statistical models we have to think why we applying that and we have to interpret the results accordingly. 

  • Nazir Hussain added an answer in Agriculture Research:
    How I might set up experiment for quantifying the effect of saline water on crop plants with minimal variation?

    Breeding for salinity tolerance

    Nazir Hussain · Shell Global

    You can do preliminary screening in pots or hydroponics but must do some field experiments to get reproduceable data.

  • Chong Zhang added an answer in Sedimentary Basins:
    Are there any gravity anomaly data of sedimentary basins?

    When inversion with variable density, the sedimentary basin gravity data is very helpful. I need this kind of data which provides the gravity anomalies, the general function of the variable density of this place, and the previous inversion results or geological information. It is very important for my studying.

    Chong Zhang · Jilin University

    Thank you Massih Afghah, I have read the articles which you mentioned, but actually I need the real data which you said to test my method.

  • Saqib Siddiqui added an answer in Nanocrystals:
    What techniques and instruments are suitable for nanoscale surface characterization ?

    For example, if I wanted to quantify number of surface ligand at the nanocrystals surface, what techniques and methods are available to use ?

    Let's say,  it is 10 nm iron oxide (maghemite) nanoparticles stablized with oleic acid.

    Any suggestion or link to relevant articles ?

    Saqib Siddiqui · Sungkyunkwan University

    SEM, TEM, AFM, Raman, XRD, XPS, EDS

  • Subhash C. Kundu added an answer in Native Language:
    Why English is the dominant language of business?

    As companies “go global” from wherever they are headquartered, they are forced to address language barriers with their overseas employees and customers. Global organizations are increasingly choosing English as their common communication language, even though more people speak Chinese worldwide than any other language. Adopters of English include Air-bus (headquartered in France), Daimler-Chrysler (United States), Fast Retailing (Japan), Nokia (Finland), Samsung (Seoul), and SAP (Germany).
    A worldwide study indicated that 25 percent of jobs require employees to interact with people in other countries, including over jobs for more than half the workers in India, Singapore, and Saudi Arabia. Of these jobs, two-thirds require English. “English has emerged as the default language for business around the world," concluded Darrell Bricker, CEO of Ipsos Public Affairs.
    One reason English is the dominant language of business and of the Internet is that it is the native language in over more than 60 nations, and increasingly the official secondary language elsewhere. While employees in native English-speaking countries are at a distinct advantage, so are employees in countries where English proficiency is high, such as Singapore, Malaysia, Scandinavia, and the Netherlands. Employees in other nations where English proficiency is lower—such as Panama, Saudi Arabia, Thailand, and Libya—are conversely disadvantaged.
    Establishing English is not just a matter of teaching employees the language. Change brings shock and threatens the cultural identity of some people, while others may not be able to master a new language quickly. As a result, team dynamics and performance can suffer, compliance may be unreliable, cohesiveness may faction, employees may stop sharing needed information, and good people may terminate their employment.

    Sources: D. Clarke, “English— – The Language of Global Business?” Forbes (October 26, 2012), http://www.forbes.com/sites/dorieclark/2012/10/26/english-the-language-of-global-business/; J. Lauring and J. Selmer, “International Language Management and Diversity Climate in Multicultural Organizations,” International Business Review (April 2012), pp. 156–-166; L. Louhiala-Salminen and A. Kankaaranta, “Language as an Issue in International Internal Communication: English or Local Language? If English, what English?” Public Relations Review (June 20120), pp. 262–-269; C. Michaud, “English the Preferred Language for Business: Poll,” Reuters (May 16, 2012), http://www.reuters.com/article/2012/05/16/us-language-idUSBRE84F0OK20120516; and T. Neeley, “Global Business Speaks English: Why You Need a Language Strategy Now,” Harvard Business Review (May 2012), pp. 117–-124.

    Subhash C. Kundu · Guru Jambheshwar University of Science & Technology

    The fastest-spreading language in human history, English is spoken at a useful level by some 1.75 billion people worldwide—that’s one in every four of us. There are close to 385 million native speakers in countries like the U.S. and Australia, about a billion fluent speakers in formerly colonized nations such as India and Nigeria, and millions of people around the world who’ve studied it as a second language. An estimated 565 million people use it on the internet.

    There’s no question that unrestricted multilingualism is inefficient and can prevent important interactions from taking place and get in the way of achieving key goals. The need to tightly coordinate tasks and work with customers and partners worldwide has accelerated the move toward English as the official language of business no matter where companies are headquartered.

    --- English is the main language of these countries where there is lots of languages spoken, like in India where more than 700 languages are spoken by their local people.

    --- is also one of the most studied language all across the world, most of the countries teach it as a second language from primary school.

    --- As per the statistics, it said that the English language is one of the easiest languages to learn, if we compare it with languages like Chinese, German, French and even Spanish.

    --- Worldwide we see that most of the communication sources, information and material sold or given to us are in English, for example: films, TV shows, music, documentaries, popular brands

  • T V K RAJU Bharatam added an answer in Oil Refining:
    What are typical concentration ranges of Carbazole and Acridine in petrochemical and oil refining Industries wastewaters (in India and in the world)?

    Please mention any authentic data source/research article if you know.

    T V K RAJU Bharatam · FREELANCER

    to the best of my knowledge, industrial waste water is not analyzed to identify species in it. i had checked with few friends. they could not help for the same reason.

    it may be easier for you to take an untreated waste water sample from refineries, petrochemicals near to mumbai and use it for your purpose.

    the presence of carbazole and acradine may be related to particular process, feedstock processed.

    you may ascertain the possibility of these two chemicals being present before approaching the refinery or petrochemical complex.

    iit mumbai has good relations with reliance group. it should be possible for you to get samples from them. since theirs are the complex facilities, it is likeli that these may be present in their waste water.

    best wishes to you. 

  • Eric van der Graaff added an answer in Microtome:
    What method is optimal for preparing a chickpea tissue sample (leaves, stems and root) for cut in a microtome?

    What method is optimal for preparing a chickpea tissue sample (leaves, stems and root) for cut in a microtome?

    Eric van der Graaff · University of Copenhagen

    Dear Yasir,

    Here is the protocol I used for parafin embedding. Please let me know when you have further questions.

  • Arun Jugran added an answer in DPPH:
    How to make an Ascorbic acid calibration curve for DPPH antioxidant activity?

    Does one use only one concentration of ascorbic acid and measure over time to get the linear equation? Or use several concentrations? Is it advisable to use dilutions of blank DPPH solutions as a standard curve and ascorbic acid as a positive control?

    Arun Jugran · GB Pant Institute of Himalayan Environment and Development

    Hi Arwen M Milroy

    it is always better to use several concentrations of a standard. In this way you can calculate the precision of your assay . By calculating the coefficient of the determination you can check the robustness and degree relationship through regression analysis. And once R square value is more the 95% your assay, handling and concentration vs absorbance relation graph is highly accurate. Hope this will help you all the best 

  • Nazir Hussain added an answer in Soil Salinity:
    What is the salt tolerance level of guava plants specifically in relation to soil texture?

    Guava plant

    Tolerance to saline water, saline sodic water and sodic water?

    Tolerance level in saline soil, saline sodic soil and sodic soil?

    salinity/sodicity tolerance in relation to soil texture?

    Nazir Hussain · Shell Global

    Good response from two specialists; Anoop Kumar and Reddy. Yes, Guava plant is not high tolerant of salinity and sodicity. Sodic water and sodic soils do more damage compared saline water and saline soils because of degradation of soil physical properties in case of the former. Water infiltration, decrease porosity and root aeration are the major problems emerging when sodic water is used for irrigation or the soil is sodic. Soil texture is very important factor for salinity and sodicity tolerant of almost all plants. There is high level of tolerance in sandy and loamy soils compared to clayey soils, especially to that of sodicity. My aim of this question is to get information and data specifying tolerance level of Guava plant to each type of water and soil salinity/sodicity with respect to soil texture. Mostly such details are not available in many countries. Sharing of information and data will help researchers, if it is available. In case of absence of such data, it is time to go for investigations to so much details. Time has reached to surpass to mention just the general and average conditions. 

  • Yuriy Pilgun added an answer in Laser Scanning Microscopy:
    Does 4Pi microscope need delay lines?

    I want to build a type C TPE 4Pi microscope with pulse laser (2 um,100fs) for illumination. I have read some paper about the experiment setup. In their experiment they do not mention whether they use a delay line or not. If I want to build this 4Pi system, do I really need the delay line? Or, it depends on the coherence length of the laser

    Yuriy Pilgun · National Taras Shevchenko University of Kyiv

    If you are trying to build 4Pi microscope, the sample should be illuminated by two opposing objectives coherently. To achieve this you will need to match optical path lengths for laser beams coming from different sides. It is almost impossible to do it without delay line, just because light pulses are very short, and they should come to the sample at the same time. Light travels 30 μm in 100 fs, so you will need delay line to compensate such a small differences in optical setup adjustment.

  • Malka Mustaqim added an answer in Insect Behavior:
    What is the best terminology a pregnant insect?

    In its life cycle, Rice bug (Leptocorisa oratorius, Fabricus) lays hundreds of egg on paddy leaf. Before egg released, Rice bug saves its eggs in abdomen which makes its abdomen bigger than normal size. Do you know what is the best terminology for this case? Pregnant? Gravid? or others? 

    Malka Mustaqim · Aligarh Muslim University

    gravid female

  • Jeanetta Mastron added an answer in PubMed:
    When you are planning to begin a new scientific project, what and where do you first search? Pubmed? Where else? Meta-analysis? Case reports?

    Is there other security source?

    Jeanetta Mastron · American University of Health Sciences

     Dear Henrique Furlan Pauna,

    You are most welcome!

    I have a question for you.

    Because you posted a link to Pub Med, are you advocating this or are you simply trying to find other search engines for scientific articles?

    Thank you in advance,

    Jeanetta Mastron

  • Deepak Samuel Vijay Kumar added an answer in Bivalves:
    Can anyone please help in identifying these gastropods and bivalves?

    These were taken from Bagac, Bataan, Philippines and we undergraduate Ecology students are being tasked to identify them down to species level if we can.  However, we are not marine biologists so we are really struggling right now.

    Deepak Samuel Vijay Kumar · National Centre For Sustainable Coastal Management

    All the best Catherine..

  • Dmitry A. Zatsepin added an answer in Thermal Plasma:
    What will be the reason for increase in binding energy in Fe3O4 XPS? Is it due to the extra phase present or just because of higher oxidation state?

    I have synthesized Fe3O4 and g-Fe2O3 thermal plasma and have slight presence of a-Fe2O3, but unable to distinguish them by XRD so I switched to XPS but when I have compared my binding energy values with published one, Fe3O4 is showing value around 713eV and for g-Fe2O3 it is around 711eV. can anybody please explain is this correct? 

    Dmitry A. Zatsepin · Russian Academy of Sciences

    Dear Suyog Asaram Raut,

    1.An XPS Fe2p 3/2 - 1/2 binding energy region overlaps strongly with Ni LMM Auger peaks, e.g. in some steel samples (or contamination with Ni) so sometimes it is the need to employ the weaker XPS Fe3p or XPS Fe3s peaks for clarification instead of Fe2p. Sometimes it is also the need to apply Degauss samples before analysis (but it depends on the type of XPS system - whether magnetic or electrostatic "lenses" are employed by manufacture of an XPS system. I.e. XPS Thermofisher XPS 250 X and Xi has magnetic "lenses" opposite to PHI Versaprobe 500 with electrostatic. Fo PHI XPS there will bo need to apply the Degauss).
    2. Iron oxides might be strongly reduced by argon-gun  sputtering. REMEBER ABOUT IT ! Thus You need to employ thye most soft possible mode for cleaning an Fe-oxide sample surface for XPS Elemental Analysis. This will minimize but, unfortunately, does not completely prevent the reduction effect.

    This what concerning correct prepararions and correct application of XPS experiment for Fe-oxides.

    About Binding Energies:

    Fe-metal 706.7 eV, FeO  709.6 eV,  Fe2O3 710.8 eV,  Fe3O4 712.1 eV

    As You see, the BE values are increasing in this set from Fe-metal to highest oxide Fe3O4. This mean Your are observing the chemichal shift in binding energies for these samples. Chemical shift means the change in binding energy of a core electron of an element due to a change in the chemical bonding of that element.

    At the same time, the BE will be determined by the following:

    - electrostatic interaction on the whole;

    - the electrostatic shielding of the nuclear charge from all other electrons in the atom and the valence electrons  are also included;

    - removal or addition of electronic charge as a result of changes in bonding will alter the shielding;

    The simple rule have to be remebered:

    Withdrawal of valence electron means charge increase in BE (oxidation)

    Addition of valence electron means charge decrease in BE (restoration).

    What about metal to oxide BE shift (an example with Li):

    Metal - Binding Energy is lower due to increased screening
    of the nucleus by 2s conduction by 2s electrons

    Oxide - Binding Energy is higher because Li 2s electron density is lost to oxygen

    (have a look an attached figure).

    This is in breaf.

    About Fe oxides XPS the preliminary information is here:

    http://xpssimplified.com/elements/iron.php   or here:


    Hope it will be useful.

    Wih regards,


  • Debabani Roy Chowdhury added an answer in Nuclear Matrix:
    What is the best approach to distinguish between nuclear protein that associates to chromatin and others do not?

    I am working on two proteins that interact to each other in the nucleus. However, I do not know whether this couple associates to chromatin or not. therefore, I am looking for the best approach by which I will know my proteins are associate to the chromatin not only in the nuclear matrix. Any help would be appreciated. Thanks

    Debabani Roy Chowdhury · Centre for Cellular and Molecular Biology


    You could try Chromatin immunoprecipitation or ChIP assay.

  • Hiba Mahmoud added an answer in Contrastive Linguistics:
    Is there any difference between contrastive Linguistics and comparative Linguistics?

    The literature online is very confusing!

    Hiba Mahmoud · Wadi International University

    Thanks a lot Antonio....your answer makes things clear for me!

  • Marianne Allison Lee added an answer in Ethnobotany:
    Which is the best way or method to attract the attention of a new generation on the direction of the ethnobotanical heritage protection?

    What is your experience or offer(s)?

  • Panduranga Rao added an answer in Virus Isolation:
    What are the reasons for infectious bursal disease virus isolate testing positive for VP1 and Negative for VP2 or vice versa after RT-PCR ?

    What are the reasons for infectious bursal disease virus(IBDV) isolate testing positive for VP1 and Negative for VP2 or vice versa after RT-PCR ? We are doing research on IBDV and some isolates were positive for one segment (VP1 or VP2) only after RT-PCR. 

    Panduranga Rao · Ella Foundation

    IBD has segmented genome and the segments can re-assort with each other. Analysis of isolates positive for one segment and negative for another may reveal interesting reassortment events. 

    The primers are designed based on the sequence of viruses circulating in industrial countries. The diversity in those countries may be limited compared to the diversity present in  Africa.

    Get some of the variants sequenced for interesting results.

  • John P. Mullen added an answer in MATLAB:
    My matlab program on backward forward sweep keeps returning the answer as NaN. what could be the possible errors?

    i am using the code given below 

    I modified the input data for a 13 bus system. However both busvoltages and linecurrent matrices are being calculated as NaN. Please help

    John P. Mullen · New Mexico State University

    You could also be having an underflow problem leading to a division by zero result or something like that. This sometimes happens when you search too large a solution space. You can try reducing the range of your search variables to see if the problem goes away. Another way this can happen is when the order of operations leads to underflow in intermediate results. For example, calculating 50P25 as 50! / 25! rather than iteratively as 50/25 x 49/24 x etc.

    It sometimes helps to print out some intermediate values, too.

  • Dilmini Karunaratne added an answer in Ranking:
    How do you effectively use logbooks in the undergraduate medical setting?

    I've too frequently seen and had to fill out logbooks that were nothing more than a glorified attendance log. What are techniques that you have seen used to make logbooks an effective tool to promote self development among medical students. Then how do you address the need for some sort of attendance log during clinical placement?

    Logbooks are an essential part of medicine that spans all the ranks, but using them effectively for each stage of training is something that I believe still needs to be worked on!

    Dilmini Karunaratne · University of Kelaniya

    I also doubt the use of log books in the medical field. A more useful version of it would be a portfolio with reflective logs of the students on their learning experiences and how they plan to improve on them.

  • Abbas Cheddad added an answer in Object Detection:
    How do I count the number of detected human object in a single image?

    I am working to count the number of human object that was detected on my camera. Until now I am success to separate the object and background. But I cannot count the number of detected object in simple way. There is any answer to help me to solve this problem? Thanks

    Abbas Cheddad · Karolinska Institutet

    You have stated in your question that you have already detected human objects. Some answers here are addressing the issue  of detection rather than the counting that you have raised...

  • Shyam Lakshmanan asked a question in Rapid Tests:
    What would eb a quick method for determining K2O content in boiler ash?

    We run a empty fruit bunch fibre biomass boiler and are looking to market the boiler ash to plantations for use as fertilizer.

    Several test results have yielded K2O content ranging from 5-10% in the ash due to presence of contaminants.  Can anyone advice a rapid test method for determining K2O content in the ash?

  • Subhamoy Sen added an answer in Computational Engineering:
    Anyone familiar with integration of EMA and FEM (mode shapes)?

    Dear All, i`m trying to make modal updating FEM model according to experimental modal analyzes. Question is from EMA, i get the complex modes but on the other hand from FEM (in my case Abaqus), i get the real modes. For model updating, should i use these two modes (fem-ema) or i must convert complex mode shapes first and then i make the optimization?

    Subhamoy Sen · IIT Kharagpur

    MAC COMAC can handle complex eigenvalues as well.

  • Mohamed Mohamed Battour added an answer in Trust:
    GlOBalization! Trust Is an Issue؟

    Research has shown that one of the greatest barriers in negotiating across cultures is trust. People in one culture are generally less trusting of those in another, including when negotiating.
    One study of Indian and U.S. negotiators found, for example, that respondents reported having less trust in their cross-culture negotiation counterparts. These lower levels of trust were associated with lower discovery of common interests between parties, which occurred because cross-culture negotiators were less willing to disclose and solicit information.
    Another study found that both U.S. and Chinese negotiators tended to have an in-group bias, which led them to favor negotiating partners from their own cultures. For Chinese negotiators, this was particularly true when accountability requirements were high.
    So what can we do to establish trust and reduce in-group cultural favoritism? The first and foremost step is to recognize that it is critical to build trust: try to get to know your counter-part, begin with small wins, and continue to communicate your interests and check your understanding of your counterpart’s interests. The challenges of cross-cultural negotiation mean that the tactics we’ve described in this chapter are even more important to successful negotiations.
    Sources: Based on B. Gunia, J. Brett, and A. Nandkeolyar, “In Global Negotiations, It’s All About Trust,” Harvard Business Review (December 2012), p. 26; W. Liu, R. Friedman, and Y. Hong, “Culture and Accountability in Negotiation: Recognizing the Importance of In-Group Relations,” Organizational Behavior and Human Decision Processes 117 (2012), pp. 221–-234; and B. C. Gunia, J. M. Brett, A. K. Nandkeolyar, and D. Kamdar, “Paying a Price: Culture, Trust, and Negotiation Consequences,” Journal of Applied Psychology 96, no. 4 (2010), pp. 774–789.

    Mohamed Mohamed Battour · University of Malaya

    attached paper is excellent in this topic. all the best Bro.

  • Sarah Giers asked a question in Molecular Clocks:
    How to use MEGA to compare more than two sequences?

    I figured out how to run a test of a molecular clock and how to run a Taijima's relative rate test. However, I really need to be able to make comparisons across more than just two gene sequences. So neither of these are very useful. I tried the "Compute Treeline" one, but it requires a tree in Newick format. It won't accept the tree files I made in MEGA itself. Is there a way to either format a tree in MEGA so it can be read in Newick format or a different test which would work better?