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  • Sarwan Kumar Dubey added an answer in Fertilizers:
    As we can quantitatively measure damage caused by urea fertilizer in the soil?

    I have not found a job that quantitatively demonstrate the damage caused to the soil in which damage the physical or chemical properties of this.

    Sarwan Kumar Dubey · Central Soil and Water Conservation Research and Training Institute

    Hi Ulises Lopez; Following link from EPA may be helpful to you.


    Good luck

  • Mostafa Eidiani added an answer in DIgSILENT:
    How can I model the synchronous condenser in the DigSilent?


    I want to model the synchronous condenser in digsilent. But i cant do this.

    Mostafa Eidiani · Khorasan Institute of Higher Education


    Ok. Simulation is correct.

  • Syed Amin Tabish asked a question in Transport:
    Should patients of cardiac arrest be taken to hospital?

    Out of hospital cardiac arrest is a leading cause of premature death, and overall long term survival is about 10% .Two schools of thought towards cardiopulmonary resuscitation. Clinical decision rules clarify when further resuscitation and transport to the hospital is futile and offer the potential to reduce ambulance transport and its inherent costs and risks. Should cardiac arrest patients be taken to hospital?

  • Miranda Yeoh added an answer in Health Research:
    What are the diet practices of researchers; are they based on health research?

    At a time when viruses are mutating, and vaccines are still being tested, and new diseases causing deaths; what are the diet practices of researchers and scientists. Are our practices in line with our knowledge, and current health research?

    Miranda Yeoh · Kolej Matrikulasi Selangor, MALAYSIA (Selangor Matriculation College)

    Dear Enzo, here I see now that you are talking about spiritual food, self examination and prayer.  And when  I do that I will always be more humble, because then I find that there are several duties more to perform.

  • Catherine Chauvel added an answer in Cleaning:
    How can I clean historical stones from fungus?

    How can I clean historical stones from fungus without damaging stones

    Catherine Chauvel · University Joseph Fourier - Grenoble 1

    personnally I would use bleach because it is very unlikely that it dissolves any rock. In addition, you should not need to brush.

  • Ahmed Abdel-Salam Issa added an answer in Cell Size:
    Can you identify this species?

    I isolated this species in the Arabian sea. (Salinity 32, growing SN medium/F/2 medium in growth chambers with light period.)

    Each cell has the size of ~2 um.

    Ahmed Abdel-Salam Issa · Assiut University

     yes i think a species of  Prochlorococcus.

  • Syed Amin Tabish asked a question in Teenage Pregnancy:
    How can the problem of Teenage pregnancy be addressed? What are the effective interventions available?

    Teenage pregnancy remains a major public health concern worldwide. The WHO has estimated that every year 16 million females aged 15-19 and around one million girls aged less than 15 give birth. Complications during pregnancy and childbirth are the second cause of death in 15-19 year old females globally. Moreover, every year around three million girls undergo unsafe abortions. Teenage mothers are at increased risk of adverse pregnancy outcomes, the effects of which seem to be reduced by optimal antenatal care. Are there any effective interventions to reduce the burden of teenage pregnancy?

  • Manuel Morales added an answer in Epistemology:
    What epistemologies currently exist for the notions of space and time?

    I am designing a study on the nature of space and time from the point of view of relativity and quantum mechanics.

    Manuel Morales · Institute of Prephysical Research

    "What one actually follows in any experiment is a succession of states, with many parameters changing. Why finger one or another ?"

    A: There has never been or ever will be an experiment conducted without a selection first being made.

    What we think of as "causality" is that it is effectual, not causal - BIG MISTAKE! As the findings from my 12 year experiment has show, states such as A and B do not exist until they do. The current logic we use to perceive reality inherently places effect (that which can be observed and measured) prior to cause.

    Ruthie, you are more on tract to what is wrong with our current logic than you know.  To think that existence of something begets the existence of something else says nothing about how existence came to be in the first place for it ignores the relationship of non-existence. As the findings show, energy and the two acts of selection are one and the same. And since the acts of selection are finite and do not exist until they do, energy is not conserved.

    Ask yourself this simple question, can you exist without making a selection? Yet, this is what we all do throughout our entire lives... until we no longer can. As the findings show, the logic my fellow colleagues here are using violates temporal precedence. 

  • Ali Ahmed asked a question in RF Sputtering:
    What are the important parameters of Molybednum coating?

    Dear all

    parameters of Molybednum coating  

    I am asking about the conditions for coating with pure Molybdenum (Mo) not oxide using RF sputtering method. particularly the temperature, pressure, power and the mixture of O2 and Ar gases and any other parameters.

    I appreciate any assistance.

  • What is the main difference between performance measurement and performance evaluation?
    Are such tools like balanced scorecard and key performance indicators tools of P. Measurement or P. Evaluation?
    Karwan Sherwani · Ishik University

    Thank you for your kind Answers.

  • How can we prevent or minimize female genital cutting or mutilation or female circumcision?

    It is estimated that 125 million women and girls worldwide are currently living with the effects of Female genital cutting (FGC) or mutilation (FGM) or Female Circumcision, and a further 30 million girls are at risk of being cut within the next decade. According to a study, 137 000 women and girls living in England and Wales have undergone FGC. As FGC carries enormous medical and psychological consequences, it is essential for healthcare professionals to be aware of this practice. One way of ensuring that doctors have at least a basic understanding of FGC is through undergraduate training.  How best we can prevent or minimise the problem of FGC?

  • Evangelia Kyriazi added an answer in SEM-EDS:
    What is the chemical structure of microorganisms on stone?

    I am looking at some fossil samples on SEM-EDS and I have located several different species of mucroorganisms. Some are rich in C, but in some I also find Fe, Ti, Si, Al, Ca, Mo etc. I was wondering if you could help me by telling me what kind of chemical elements I should be expecting to find on chemiolithotroph, biomineralising and other microorganisms found on stone. The fossil I am looking at is a silicified tree from Thailand found in ancient river sediments. Any help and relevant papers would be more than useful. Thank you.

    Evangelia Kyriazi · University of Peloponnese

    Thank you Phil for this interesting paper.

    Most of the microorganisms I have detected are living ones (or at least used to be until I put them in the SEM-EDS and started "bombarding" them!) . I do not dare to make any assumptions about biological classification, as I am a objects conservator specialised in petrified wood conservation, and not a microbiologist. I have detected more than a dozen of formations that look like contemporary microorganisations that have the appearance of bacteria, fungi and algae, and I think I may also have some amoebas.The formations I have detected are of various sizes and shapes and with different chemical compositions.

    The preprints with the abstracts of the presentations of the 4th ARCH_RNT have been published, but I do not have a digital copy of the abstract of my presentation at the moment. The following 2 paragraphs include copy-pasted information from the abstract that I had submitted and from the texts in my presentation.

    Morphologically, they can be grouped into longitudinal, branched, sheet and spherical formations. Some are found as individual appearances and others form colonies. Their location and agility also vary: some seem to be attached on amorphous fossil surface, certain types are attached on silica crystals, while others seem to pertain the ability to move on the fossil surfaces either by rolling, or through the use of thin "strings", covering long distances in relation to their size. In some cases, trace marks were observed, while needle-form cavities were also observed. Qualitative analysis indicates that chemically, the types of microorganisms may be grouped into carbon-rich, silicon-rich and iron-rich formations

    My limitations using SEM-EDS are that this method is unable to detect chemical elements lighter than Na, therefore it cannot be trusted for N, H detection; it cannot be trusted for C detection; there are high limits of detection; it is a semi-quantitative analysis and most taxonomic errors are due to visual observations. However, using SEM-EDS has its advantages as I was able to study surface structures <1μm. In some cases I managed to get as close as x3000, but the shape of the samples does not allow to see or do analysis on formations located within cracks or crevices in the samples.

    The only ones (so far) that look like fossilised are some formations that look like algae (long, kind of wide, striped, kind of transparent) and on one occasion I found a spherical formation with lots of tiny little holes that gave me the impression of a fossilised diatom, although it could also be somekind of microspore.

    I would like a cooperation with a microbiologist so I would not jump into quick conclusions. If you think you can help, e-mail me at kyriazievangelia@gmail.com and I will be happy to share some SEM-EDS pictures and spectra so we can discuss about my findings. My work is still in progress, and due to the number of samples and the high magnification I am looking at them, I am hoping to be able to finish this part of my research by January.

    Thank you for your interest


  • Sirajus Salehin added an answer in XRD Analysis:
    What are crystallite height and diameter values in XRD analysis?

    I have performed XRD analysis for my oil fly ash samples. I have the results and I want to make a tabular representation of these data such as inter-layer spacing (d), crystallite height (Lc), crystallite diameter (La) values to compare with natural graphite. 

    But I don't see any thing mentioned as Lc or La in my result sheets. I've got the 'd' values and there is a term 'Crystallite size' with values around 13-14 angstrom. 

    I don't understand, which value is this? Is it Lc or La? Plus I would appreciate if you can show me some different analysis with XRD results for my thesis. 

    Thank you very much for your time!!

    Sirajus Salehin · King Abdulaziz University

    Thank you all.

  • Which statistically comparison test is most accurate for genotoxic studies?

    I did a little research and I realized that researchers used very different tests even in same conditions (Anova, Mann Whitney U, Kruskal Wallis). In my study, i used 4 volunteers for their lymphocytes. I performed chromosome aberration, micronuclei and SCE tests. But I could not decide the test for statistically comparing my results. What are your views? thanks.

    Taygun Timocin · Cukurova University

    First of all thanks for answers. But I mean that statistically comparison tests such as Anova, Mann Whitney U.

  • Sarwan Kumar Dubey added an answer in Water:
    Does anyone have information on why groundwater at the shores of a freshwater lake may be salty?

    I think that it may be a geological problem but I have no information..

    Sarwan Kumar Dubey · Central Soil and Water Conservation Research and Training Institute

    Hi James Kiyengo; I do agree with the answer given by Prof.Ajay Singh, Other then sea water intrusion even all fresh waters also having some salts. Level of water in lake pushes the water far from the lake and evaporate from soil surface leaving behind salts which leached again with pushing water. Hence over the time salt concentration could also increase in shores. Thanks

  • Tauqeer Hussain Shah asked a question in Mind:
    How to show that the integral is convergent or divergent?

    I have an integral and wanted to see whether it converge or diverge. I know there are many methods that can be used to show it.

    Note that -l(ell) to l(ell) belong to real numbers.

    I have comparison method in my mind, but I stuck with it. Any other suggestions will be highly appreciate 

  • Jumana Saleh added an answer in Lipids:
    How did saturated fats affect the formation of LDL (Low density lipid) cholesterol ?

    Recent studies show that there is no significant results of saturated fats influenced the heart attack, atherosclerosis, etc. However there are many statements that mentioned the saturated fats form LDL cholesterol which the factors of the diseases. No clear explanation was provided together with the statement. Hope the researchers of this field can give some assistance. Thank you.

    Jumana Saleh · Sultan Qaboos University

    Saturated fats are carried on lipoproteins called VLDLs that are produced from the liver and convert to LDL quickly in the circulation. VLDLs are stripped from the triglyceride content by lipoprotein lipase in the circulation and convert to the cholesterol dense lipoproteins called LDL and even more into small dense LDL which is highly oxidizable and contributes to the formation of atherosclerosis. 

  • Harita Desai added an answer in Zeta Potential:
    Zeta potential of Calcium-alginate nanoparticles ?

    Does anyone have some articles treating the zeta potential of this nanoparticle ? Thanks 

    Harita Desai · Institute of Chemical Technology, Mumbai

    Hi, pls find the links.



  • J Perriot added an answer in Scientific Publishing:
    What would you do if you received a report from the reviewer of your paper asking for a major revision, with which you completely disagree?
    What would be your response? Would you appeal to the editor by asking him/her to make the final decision, would you be weak and amend what you believe is right, would you argue back with facts, would you re-submit the paper to another journal?
    J Perriot · Conseil general du Puy de dôme

    In my experience; in the journals in which I had submitted a manuscript... when the paper is refused...it is refused: no question to discuss the decision with the Editor (one experience...).  It is always possible to respond to the reviewer but I consider I only have to clarify questions asked but not to defend my paper or my opinion... I must respect the final decision  (there are many other journal to submit).

  • Ghanbar Barzegar added an answer in Abaqus:
    What is the expression for torsion vibration of thin plate?

       I am doing modal analysis for composite plate using Abaqus. I want to do sanity check to ensure that FEM results are right or wrong. 

    Ghanbar Barzegar · alucastiran company


    please say more detail about your ask

  • Is there a validated scale which investigates parents supportive behavior in their children's mathematics education?

    I am working on parental beliefs about mathematics and it teaching and learning and want to investigate, in which ways parents support their children with their mathematics education. Therein I am focusing on early secondary school (11-12 year old students). 

    Natascha Albersmann · Ruhr-Universität Bochum

    Dear Tobias Linberg,

    I am not quite sure whether those papers focussing on numeracy fit to my approach, but I will have a look. Thanks!

    Hi Kevin,

    the transition is exactly the context in which I situate my research. When I will proceed with my work and will have a publication, I will add it here,  so that you can have an insight. What exactly are you investigating with regard to teachers?

    Hey Abdel,

    thanks for your ideas. i did check some scales from other projects with parents, but did not find a fitting combination of characteristics. I will have a look at "Parental Involvement and the Theory of Planned Behavior". That I didn´t check. Thanks a lot for that thought!

    Thank you all a lot for your help!!

    Best regards,


  • Abdul Rahim added an answer in Preparation:
    Any suggestion to deal with copper(I) chloride without using anaerobic condition or chamber?

    Hi there....i'm now deal with copper(I) chloride for metal binding experiment..unfortunately, this copper(i) need anaerobic condition for it preparation because it will oxidize to copper(ii) in the presence of oxygen..isn't any alternative to prepare the copper(i) instead in anaerobic condition?...

    Abdul Rahim · Putra University, Malaysia

    Thank Manohar for suggestion...you said at number one that must used saturate CuCl..what meaning of saturate CuCl?...

  • Harita Desai added an answer in Microemulsions:
    Can anyone help with microemulsion characterization by ultrasound?

    See above

    Harita Desai · Institute of Chemical Technology, Mumbai

    Hi, pls find the links 



  • What are the adverse effects on natural recharge water?

    A number of toxic materials are distributed in our life. About 30 thousand toxic materials surround us.

    Sarwan Kumar Dubey · Central Soil and Water Conservation Research and Training Institute

    Dear R.C. Chhipa ji; Following link could be useful for you.



  • Harita Desai added an answer in Validation Methods:
    Does anyone know any methodology (ies) for separating APIs solubility by HPLC?

    I am trying to get a methodology for the solubility and then use analytic validation method of HPLC to separate the mixture of the APIs. I will appreciate any idea, please. 


    Harita Desai · Institute of Chemical Technology, Mumbai

    Hi, pls find the links.



  • Could anybody identify this macoinvertebrate ?

    I found it in my lake bottom sample when sorting for macroinvertebrates, but could not figure out what it is.

    Here is a link for more pictures and a video: https://www.dropbox.com/sh/mmbw3u5ddnhb29k/AABYx9Jj6rOjbL3_MAFhDXMFa?dl=0

    Note: these were from preserved samples

    Thank you for your suggestions.

    Best regards,


    Polain Nzobeuh · University of Jyväskylä

    Yes Finnish lake and I also thought it might be an early stage of a species of one of these two taxa but not figure out which one. Thanks for your comments.