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  • Paul Reed Hepperly added an answer in Vegetables:
    Can someone provide me experimental procedure for finding the C/N ratio of leaves, vegetable waste?

    i am confused whether procedure for finding C/N ratio for soil and vegetable waste are same.please some one provide me exact procedure to find C/N ratio of vegetable waste.

    Paul Reed Hepperly

    Dear Kotreshi B H

    If one is commercially composting using high temperature the C to N ratio must be 20 to 30 to 1 or the decomposition will not proceed with dispatch. The high heat aids the microbial process and speeds results the materials are piled to greater that 1 by 1 meter by meter to keep the temperature from being lost.  This is not appropriate for worm composting which requires moderate temperature not high heat.

    For vermicompost the pile should not exceed 50 cm in height because the high temperature is not required and appropriate. The vermicompost needs good supply of Calcium used by the worms in detoxifying the waste materials. If you have straw or leaves which are piled to less than 50 cm and 1% Calcium sulfate is applied and watered to moist not sopping.  The mix is aerobically fermented for 10 to 20 days to start microbial decomposition favoring worms.

    Place the vegetable and banana waste on the surface no more 5 to 10 cm deep. The worms that are introduced will feed on the leaves and a come up at night to consume the surface vegetables which will be incorporated into the mass.

  • Nirmala S.V.S.G added an answer in Permissiveness:
    Is it allowed to upload papers here, which are already published as articles?

    I noted that many researchers upload their articles here on RG. I would like to do the same. But is it allowed to upload papers here, which are already published as articles if you don't have permission by the journals in which they were first published?

    Nirmala S.V.S.G

    Dear Anne Merrild Hansen,

    some of the international journals does not give permission to upload the full article in RG. only abstract can be uploaded. After publication of the article they send one copy to the corresponding author as a personel copy, if any body requests the author, he might send it.

  • Hamid Tavakoli added an answer in Likert Scale:
    Which Likert scale should I prefer that of 1-4, 1-5 or 1-7?

    Hi everybody!

    I'm making a questionnaire for my students about my new teaching style. My question is about the best Lickert scale that I can use in order to they evaluate some statements: 1-4, 1-5 o 1-7? I have read about this, but there are advantages and disadvantages in each of them. Can anyone help me out?

    Thank you in advance.

    Hamid Tavakoli

    it seems,this based on the ability of the respondents and depends on the details of your study.I would recommend using 7-point scales.

  • D.P.S. RATHORE added an answer in ICP-MS:
    How reliable is the direct spectrophotometric determination of ions (not colorimetric) in water samples and / or biological extracts?

    I need to measure some ions concentrations, like phosphate, sulphate, bicarbonate, calcium, magnesium, ammonium, potassium, sodium ... but generally literature has reported colorimetric methods by direct reaction and / or by complexing. The main disadvantage of these methods is the cost of many specific reagents and / or access to modern devices for more accurate spectrophotometric determinations such as ICP-MS and atomic absorption techniques.
    On the other hand I would be interested in non invasive methods that do not destroy the biological samples for furthers determinations.
    Who can help with articles, methodologies and/or bibliographic references?

    Thanks in advance for any collaboration!!!


    There are some more interesting papers on water analysis related with uranium.

    + 7 more attachments

  • Laurensia Marcelina Anggraini added an answer in Abaqus:
    Why do I get different time step in non-linear analysis in Abaqus?

    I'm using non-linear spring in my analysis. I specified the time step to be 0.01 second, but the time increment in the xy-data is 0.1 second. The job monitor shows that the time increment is 0.01 s though.

    I was thinking to specify the time step to be 0.001s in the model to get 0.01s time step in the xy-data, but the calculation time will increase a lot.

    Does anyone know what should I do to fix the time step (to get 0.01s step) in the xy-data?

    Laurensia Marcelina Anggraini

    I checked my field and history output as mentioned by Arkadiusz Rzeczycki, and I found the problem. I can get the right amount of output data now. Thank you.

  • Vikas Singh added an answer in Solid State Characterization:
    How do I measure the thickness of thin film using Atomic Force Microscope (AFM)?

    How to measure thickness of thin film using AFM?

    I have see some people have determined thickness of thin film using AFM.

    I have also tried but found that thickness is changing with changing the scanning area.

    eg. the thickness is 13 nm for 500*500 nm^2 and around 27 for 1000*1000 nm^2

    could someone elaborate it?

    are there any other methods to measure the thickness of MBE grown thin film?

    Thank you in advance !

    Vikas Singh

    Thanks Eleonora Stefanutti 

  • David Fischer added an answer in Climate Change Biology:
    Which plant species should be taken as climate change indicators ?

    Which plant species should be taken as the indicators of climate change ?

    David Fischer

    It is what we call a "loaded question", meaning it forces a key assumption that has not been validated.  Here, the assumption is that only some plant species should be taken as climate change indicators—or that some plant species should not be taken as climate change indicators.  Robust, objective science requires that every taxon must be considered in its biophysical context.  ¶  Important pertinent note: we understand that there will be interesting outliers, i.e. some taxa will prove remarkably less or more sensitive to temperature and moisture pattern changes compared to other groups of taxa, especially higher groups farther up the same phylogenetic branch as the exceptional species.

  • Bapurao Chide added an answer in Finite Fields:
    What is the number of subspaces that intersect a fixed subpaces in zero?

    In an n-dimensional vector space W over a finite field F, what is the number of k-dimensional subspaces that intersect in zero a fixed t-dimensional subspace V?

    Bapurao Chide

    Sorry,I do not know.

  • Jaysukh B Kathiriya asked a question in Pathogens:
    What is the best method for isolation of Listeria spp. from various animal origin foods

    Many pathogens causing food toxicity.Listeria is common pathogens among them. so it's necessary to identify this pathogens properly.

  • Ramanujam Meganathan added an answer in Classroom Management:
    What are recommended references in analyzing classroom interaction?

    I'm doing my research about interaction and its effect on classroom practice process.. I need reference on how to analyze interaction completely. practical one would be better.

    Ramanujam Meganathan

    Following is one of the notes works on language classroom. This was agroundbreaking research 

    Allwright, D.  and Bailey (1991). Focus on the Language Classroom: An Introduction       to classroom research for language teachers. New Directions in Language       Teaching. Cambridge University Press.

  • Andrey I. Dmitriev added an answer in Iron Oxide:
    What are the coordinates of atoms in a Fe2O3 lattice?

    Can anyone help with atoms coordinates in Fe2O3 or Al2O3 lattices?

    Andrey I. Dmitriev

    Sure we know the difference between lattice and structure.

  • Daniel Dehany Scott added an answer in Microbiology Techniques:
    Why we first make universal culture for bacterial growth then add it to large scale?

    Why do we first make universal culture for bacterial growth then add it to large scale?

    Daniel Dehany Scott

    Hi Surog,

    There's a couple of advantages to doing this.  The main one is that, when you seed a liquid culture from cells on a petri dish, there's a "lag phase" where the cells recover and begin to proliferate exponentially.  Seeding the cells into a small culture first allows you to get past this lag phase in the small culture and ensure that the cells you're seeding into your large culture are healthy and replicating well. 

    Secondly, when scooping off a petri dish it's quite hard to quantify how many cells you're seeding, so you may have a lot of variation in your initial seeding density.  This can effect both growth time of the culture and cause biological variation.  Pre-seeding into a starter culture allows you to accurately quantify cell number in this starter culture using a spectrophotometer/haematocytometer, and therefore ensure an accurate starting density of your full-scale culture.

    I hope that answers your question.



  • Nancy Neo Etiqaz added an answer in Wood Processing:
    Is there any previous study on wood treatment using boron for cold treatment (non-pressure)?

    Is there any previous study on wood treatment using boron for cold treatment (non-pressure)?

    Nancy Neo Etiqaz

    ok ..thanks Dr...

  • A. Subba Rao added an answer in Soil Organic Carbon:
    How do I convert organic carbon (%) of soil for value & interpretation into available nitrogen (Kg/Ha) & rating?

    Say in my area soil organic carbon measured is 0.28, 0.30, 0.18 %

    as per soil fertility rating it is low in organic carbon or low in nitrogen (Kg/Ha)

    now for all my data like above I want to convert into available nitrogen (Kg/Ha)

    so what will be any formulae ?

    A. Subba Rao

    Gaur,you have to compute a regression equation between organic carbon and available N estimated by some method like alkaline permanganate method.Once if establish such relationship between the two parameters with sufficiently  large number of samples, using organic carbon values we can predict the amount of  available N.But I suggest you to go for direct estimation of available N.However in the absence of facilities,if one desires to give recommendations based on available N,then available N can be predicted from organic carbon.

  • Krishnan Umachandran 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.

    Krishnan Umachandran

    Liberty / security tension is rendered vs risk avoidance co-opts justice transforming it into more proliferational expressions of punishment.

  • Pavel Novoa-Hernández asked a question in Distributed Systems:
    What are the best books for teaching distributed systems to computer science students?

    I would like to find some updated, teaching-oriented books in the subject...Thanks in advance...

  • Hamid Tavakoli added an answer in Likert Scale:
    What statistical analysis can I use to find correlation for 1 independent variable and 1 dependent variable, both of which are ordinal?

    I am planning to conduct a quantitative research to determine 2 types of perception ( A and B ) people have and how they correlate. 

    Variable A: independent variable determined with a set of questions which are all ordinal (likert scale) 

    Variable B: dependent variable determined with a set of questions which are also all ordinal (likert scale)

    Thus I am planning to have two sections, one for determining A and one for determining B..and then I want to see if a correlation exists..

    However, I am unsure what type of quantitative analysis would be best. Your answers are highly appreciated.

    Hamid Tavakoli

    you will use Spearman's rank correlation coefficient.In correlation  IV or  DV, Not matter.

  • Justin Tan asked a question in Inhibition Studies:
    PC-3 cells as the 5a-reductase enzyme source did not produce any DHT upon incubation with testosterone, what cells i could use as 5a-reductase source?

    I am running a 5a-reductase inhibition study, but PC-3 cell lysates did not seem to produce DHT upon testosterone incubation, so what other cell lines could possibly present me with a rich source of 5a-reductase? Thank you for your help :)

  • Andrew W. Beckwith added an answer in Gravity:
    Does a uniformly accelerated charge radiate?
    In classical electromagnetism, any accelerated charge should radiate. The back reaction on the charge due to radiation is given by radiation reaction which depends on time derivative of acceleration. However for uniformly accelerated charge there is radiation but no radiation reaction. I would appreciate any comment on this apparent paradox.
    Andrew W. Beckwith

    Hi, all. I do believe this question is a bit incomplete, so let me start by posting a link to a physics arxiv article, below


    Why ? Its a bit more nuanced a situation than the initial querry indicates. 

    First, from the article above, the quote

    Does a uniformly accelerated charge actually radiate? In a constant
    gravitational field should free-falling observers detect any radiation emitted by free-falling charges? Is the equivalence principle valid for such situations?
    If the answer to the first question is affirmative, a free-falling charge will radiate according to an observer at rest, because in a constant gravitational field, any particle should move with uniform acceleration. However, an observer
    falling freely with the charge would observe it at rest and no radiation at all.

    end of quote

    Seems definitive? Well, again the article above, shows that there is more to consider, namely....

    From the article above, quote

    Inertial observers have no doubts about the answer to the first question. They will answer it affirmatively by using special relativity and Maxwell’s equations, as it is done in classical electrodynamics texts (see, for example,Ref. 6 whose conventions we adopt). Nevertheless, comoving observers, that is, accelerated observers with respect to whom the charge is at rest, will not detect any radiation because the radiation field is confined to a spacetime region beyond a horizon that they cannot access.

    end of quote

    For co moving observers, this is NOT an obvious answer, and the initial question needs a bit more specific information. 

    I post this not to say that the question as presented is 'bad physics' but to indicate what a mine field this querry really is. Any full answer will require in dept analysis of several specific cases beyond the initial question tenured for us to review.

    Andrew Beckwith

  • Krishnan Umachandran added an answer in Strategic Planning:
    What operative aspects must include in an implementation methodology for Strategic Plan?

    I need to identify the operational KPIs, that must measure it for increase the implementation probability of the Strategic Plan .

    Krishnan Umachandran

    Ten Keys to Successful Strategic Planning for Nonprofit and Foundation Leaders

    No organization exists in a static environment. Social, political and economic trends continually impact the demand for its offerings and services.Even as advances in technology present new opportunities, they also generate new expectations. Needs and community demographics are all subject to change.

  • Nobuhiro Takeuchi asked a question in Aortic Dissection:
    Is there any possibility that contrast agents may trigger the rupture of thoracic aortic dissection (Stanford A type)?

    Actually, I am concerned with the association between the use of contrast agents and rupture of thoracic aortic dissection (Stanford A type).

    Here is the case I experienced recently. A 57-year-old male with a history of hypertension and atrial fibrillation visited our department with a complaint of chest pain. His consciousness was clear and his systolic blood pressure was 100 mmHg. TTE revealed dilated ascending aorta along with moderate aortic regurgitation. Immediately, contrast-CT was performed. Contrast enhanced CT revealed Stanford A type aortic dissection. There was no retention of pericardial effusion. Within a few minutes after that, he fell into CPA. TEE revealed massive retention of pericardial effusion. PCPS was introduced. However, PCPS did not work efficiently probably because of collapse in the right heart. Immediately, pericardial drainage was performed; drainage was not effective because of coagulated blood.

    In this case,

    Should we have performed pericardiotomy to save this patient?

    May contrast agents trigger the rupture of thoracic aortic dissection (Stanford A type)? Actually, I know several cases that thoracic aortic dissection ruptured immediately after contrast CT. I want a paper discussing this point.  

  • Krishnan Umachandran added an answer in Physics Education:
    Is there effective program/model that improves elementary and high school physical education?

    I'm looking for program/model that effectively improves physical abilities/skills of elementary and high school students, and if possible free one:-). I'm aware of SPARK, which is a commercial program, but I would like to see something that is available to everybody.


    Krishnan Umachandran

    It is taught as a course to elementary, middle, high school, and college students to improve their motor coordination, physical fitness, and develop teamwork skills.

  • Chibuike C Udenigwe added an answer in DPPH Assay:
    Is the DPPH assay a very reliable method to measure Antioxidant Activity of plant extracts?

    I'm considering the use of the DPPH method in my thesis due to its relative simplicity and low cost.

    Chibuike C Udenigwe

    I concur with all the comments but, as Sameera noted, be mindful that DPPH radical is synthetic and not biologically relevant, i.e. it does not mimic any known free radical produced in biological systems.

    Moreover, the radical is highly stable (unlike biological radicals) and accessibility can be hindered by steric effect due to its bulky structure. As a result, positive effects with your compounds using the in vitro assay may not always correlate with in vivo results, i.e. if the compounds are intended for physiological application.

    I hope this helps.

  • Raju Vaishya asked a question in Efficacy:
    What is role and efficacy of PRP injections for knee OA?

    Please share your personal experience of the use of PRP

  • Krishnan Umachandran added an answer in ICT:
    Does anyone known studies about the social use of time?

    I'm interested in studies that relate the use of ICT and the social use of time

    Krishnan Umachandran

    This data collection represents an attempt to apply recent methodological developments in the measurement of time use to a national probability sample of United States households in order to facilitate development of a fully articulated system of economic and social accounts.

  • A. Subba Rao added an answer in Azotobacter:
    After incorporating azotobacter in soil or treating seeds of perennial crop at the time of sowing, is it necessary to add azotobacter frequently?

    How long Azotobacter will go on multiplying continuously   in soil after adding  ? What are the factors responsible for their decrease in population in soil ? OR simply adding organic matter in the soil will help to multiply Azotobacter , which was used to treat seeds at the time of sowing   ?

    A. Subba Rao

     Mr.Solon, for particular area and crop/ cropping system we have to give certain time frame for inoculation. The inoculum should also be able to compete with native species ,survive and maintain sufficient population to fix  nitrogen.

  • Norman Syakir added an answer in Oxides:
    Can anybody suggest literature related to MOS capacitors?

    Hello friends, I am fabricating two terminal MOS structures on SiC wafer. I want to know the details pertaining to the oxide layer, like whether oxide layer be crystalline or amorphous. Please suggest me some useful literature.

    Norman Syakir

    there is a book title: MOS PHYSICS AND TECHNOLOGY, 

  • Humbul Suleman added an answer in Equation of State:
    I'm looking for equations of state to predict solubility of O2 and N2 in Liquid CO2?

    I'm looking for equations of state to predict solubility of O2 and N2 in Liquid CO2?  These equations must be good for pressures between 20 and 150 atm and -40 to 40 degC.


  • Linda A Hershey added an answer in Alzheimer's Disease:
    What are the best cognitive tests for detecting early changes prior to the onset of dementia?
    A traditional approach is to use tests of global cognitive function such as the Mini-Mental State Exam (MMSE: Folstein et al., 1975) or the Blessed-Information-Memory-Concentration Test (BIMC: Blessed et al., 1968) to assess the severity of cognitive impairment (Tombaugh and McIntyre, 1992). But are these tests sensitive enough? Most studies show either ceiling or floor effects according to the time progression into disease.
    Linda A Hershey

    In a 60 min clinic setting, I find that Lawton's IADL scale is useful to distinguish dementia from MCI.  Then Cummings' NPI is useful to gather symptoms of DLB, FTD, etc.  The last test I do is the MMSE ( to assess severity). An MRI is important to decide on whether there are silent infarcts.  Our neuropsychologist provides f/u with more detailed testing after I provide the first suggestions for the diagnosis.  He helps with the counselling about driving cessation (I get pushback when I first bring this up, if the patient has mild dementia).