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  • Is it possible to use ditch cuttings for mineralogical investigations when one has no access to core samples?

    the research is on ironstone deposits but core samples are not available to us, can drilled cuttings be used for such investigation? if yes, which procedure would be the best for preparing the samples for trace element REE and isotopic analysis and which analytical technique will give the best result?

    Ana Maria Carmen Ilie · University of Ferrara

     I think you should make a detailed study of cuttings and samples at the same depth of the same hole, perform chemical and petrographic analysis to compare both setting data. just so, you can have an order error by cuttings. You should do a correlation with other data of nearby wells possibly from the samples and so you would have a percentage of trace elements at that depth of the cuttings correlated with the core samples data.

    To prepare the cuttings for trace element REE and isotopic analysis it would be the same for the core samples. 

  • Nitish Venkateswarlu added an answer in Chlorophyll:
    How to calculate total chlorophyll-a concentration using chlorophyll-a values at different depths?

    trapezoidal integration provides value with units of mg/m2. How to get chlorophyll value in terms of mg/m3?

    Nitish Venkateswarlu · National Institute of Technology Karnataka

    @chandan Ghosh: I already have chlorophyll-a values at discrete depths. And I want to calculate total chlorophyll-a concentration using chlorophyll-a values at different depths but trapezoidal integration provides value with units of mg/m2. How to get chlorophyll value in terms of mg/m3?

  • Athira Chandran added an answer in Happiness:
    Is there any lexical database that stores phrases and terms that has same contextual meaning as those phrases?

    I am in search of a tool capable of providing meanings to idioms and phrases. I need the meaning as well as the similar terms which can be used instead of those phrases. For example: 'on Cloud nine' : in state of great happiness, very happy and so on.

    Athira Chandran · Indian Institute of Information Technology and Management - Kerala

    Can I get  corpus or something which I can intergrate into my code?

  • Abdelhalim Zekry added an answer in ADC:
    Does the S/H circuit affect the dynamic performance of a ADC?

    I am working on 8-bit Asynchronous SAR ADC.  It uses one comparator which is needed to operate up to 256 levels.  Initially the SAR logic is set to the mid value (128 level) = (10000000)2. An input is been fed to the Sample/Hold circuit. After a small time interval all the corresponding bits in the SAR register sets to the correct logic levels as shown in the figure

    Now I open the spectrum analyzer to check the ADC Dynamic parameters. The ENOB sometimes shows up negative values, SNR, SFDR are all out of range.

    My question is does the S/H circuit affect the dynamic performance?

    How can I resolve this

    The net411 is the DAC output which settles down at the same range of the input voltage

    Thanks in advance  

    Abdelhalim Zekry · Ain Shams University

    Dear Anush,

    At first i would like to remember a concept for the measurement. It is so that you measure the quantity as you define if . So , when you measure the static parameters of he ADC you have to sick their definition and conditions of measurement.

    So, to measure the static parameters of the ADC which are related to its transfer curve you need to connect an ideal DTA converter in its output, inputting a known slow ramp voltage a its input and displaying the the output of the DAC versus the input of  THE ADC. 

    Concerning the sampling rate , i must be sufficient to cover at least the number of levels in the ADC. from the he zero voltage to the VFS voltage.

    To measure the dynamic performance parameters, it is best measured using a sinusoidal wave input with the intended frequency and oversample it o resolve the noise and distortion. That is fs must be much greater than the input signal frequency.

    You must consider that the ADC has highest conversion speed and the the sampling rate must be smaller equal the conversion speed.

    Before making any spectrum analysis on the outputs signal of the ideal DAC at the output of the ADC you have to display the signal in time domain. If the signal resembles the input then you adjusted properly your ADC and your test signal.

    I examined your attached waveform and i see that it is okay but you displayed only the waveforms for one sample only. 

    Before you analyse your signal using spectrum analyzer you must be sure that the ADC outputs the correct waveform.

    For more and useful information please go to the link:http://www.mit.edu/~klund/A2Dtesting.pdf

    wish you success

  • Emilie Houliez added an answer in Greece:
    Does anyone have an idea of what this wondrous creature might be?

    Found in a port in Greece

    Emilie Houliez · Finnish Environment Institute


    This looks like a chain of sea salps.

    Here a link to have more information about salps.


  • Mario Vincenzo Russo asked a question in Pheromones:
    Sexual attraction is a matter of feelings or pheromones?

    What is your opinion?

  • Are predictive models a useful tool in occupational toxicology?

    In terms of biomarkers of exposure to a cumulative toxic substance in the workplace. 

    In Nanotoxicology and Nanomedicine - quantitative nanostructure activity relationships is used to predict the pharmacokinetics and biodistribution of nanomaterials in the body

  • Qasim Ali asked a question in Butter:
    What is the basic morphological character for the iddentification of cabbage butter fly??

    i need identification key of cabbage butter fly.

  • Regarding this abstract, is there a system with failure interaction so that a failure of component impacts on the other component failure?

    Repairable system is commonly used in different industries and has been become more complex. In complex system, in addition to the random component failure, the effect of two component is random. The impact of failure is uncertain and can be considered as fuzzy. Fuzzy set theory has been the most important approach used to deal with uncertainty in problems. The repair of complex system divided to soft and hard. The hard failure causes the system stop and the soft failure does not, but it increases the system operating costs too. In this paper assumed: when the first component fails, it remains in a failed state until the next inspection time. Therefore, if the first component failed in each inspection interval, a downtime penalty cost is incurred. The cost is proportional to the elapsed time from failure time to its detection at inspection time. The short inspection interval increase the number of inspection and cause the extra cost for system. As well, long inspection interval will cause the greater cost due to long elapsed between real occurrence of the failure time and the failure detection (penalty cost). On a finite time horizon, the objective is to find the optimal inspection interval for the soft failure component so that the expected total cost will be minimized.

    Hindolo George-Williams · University of Liverpool

    Yes there is. In reality many systems are prone to common-cause/cascading failures (i.e failure of one component leading to failure of another). Consider a parallel system of two resistors of equal resistance values supplying say a 5A load. When both resistors are in operation, the current divider rule states that each will carry 2.5A. If one resistor fails, the other resistor would have to carry the full load which is twice what it carries if both resistors function correctly. This increase in load increases the failure probabilbity of the functioning resistor thereby accelerating its failure. Depending on their maximum current rating, failure of one resistor may lead to an almost instantaneous failure of the other which is the case if this maximum rating is say 3A.

  • Prabhat Chandra Mondal added an answer in Gynecology:
    Is female sterilization using Pomeroy's Technique justified in all cases?

    As per rule/law, at least in India, we have to perform female sterilization with Pomeroys technique. But over the years, I came across several cases, where I feel this technique should not be used in some cases. For example
    Previous 3/4 cesarean section
    Previous rupture uterus and scar dehiscence this time
    Scar dehiscence without labour in previous one scar
    If we perform pomeroy's technque in these cases, there is a little chance of spontaneous recanalization, and surgical recanalization is never intended or advised in such cases.

    Prabhat Chandra Mondal · Bankura Sammilani Medical College

    Dear Dr.

     Your said, "As far as salphingectomy is concerned in such cases, WHY NOT. It is the most viable option. Even if there is minimal evidence in support of this procedure preventing any major illness, why not perform it when u r not doing any extra special surgery for this (abdomen is already opened)."

     Now, Why don't you include this in your opinion. Now, you are agreed to the followings

    1. Apart from modified Pomeroy's, fimbriectomy is an option.
    2. Salpingectomy is an another option.

    Enough discussion, this is the time to know which option has come out for Indian women in the following situations.

     The review committee appointed by the honorable Supreme Court is flexible. They reviewed the technique exclusively done in India, and made a guideline for practicing doctors. This does not restrict to make a new study proposal in a medical college, rather it would be welcomed. If you argue on this topic, you might get the permission.  

  • How do I validate vulnerability maps?

    I prepared physical and social vulnerability maps of Seoul and Busan megacities. But I could not find the methods to validate those maps.

    Tamasha Fernando · Central Environmental Authority, Sri lanka

    You may use the historical data available in these mega cities. Also you may done a questionnaire survey for selected sites. Stratified sampling technique is best I think.

  • Mohsen Salari asked a question in OpenSEES:
    How can I use bouc-wen model in opensees softwrare sufficiently?

    I model single degree of freedom dynamic system with bouc-wen model for apply non-linearity of the system in the OpenSees software. and excited it by an earthquake excitation. However the model work linear instead of non-linear. I change the value of alpha but the model work linear again. I want to know why it not work properly and have any one any example for using bouc-wen model in opensees software?

  • Nischith Raphael asked a question in Radioactivity:
    Is there any relationship between Radioactivity and CNT synthesis and growth?

    I would like to investigate behavior of CNTs on radioactive materials as catalyst or substrate. 

  • Is it possible to NMR to distinguish between the different isomers of chlorogenic acdis?

    I am interested in the analysis of chlorogenic acids with NMR. I would like to know if is it possible to differentiate between the different isomers in a crude extract or one will need to first separate these isomers i.e on a HPLC/capillary electrophoresis before analyzing then on NMR. 

    Please if you to have papers on NMR metabolomics specially isomers analysis where chemical shifts have been used to distinguish isomers send them to me. 



    Paul Anton Steenkamp · Council for Scientific and Industrial Research, South Africa

    Hi Msizi,

    As correctly highlighted by Fidele you need to be skilled in NMR to do these type of NMR studies to differentiate isomers. These type analysis would also require pure compounds.

  • Satish Verma added an answer in Sports Physiology:
    What are the differences in foot contact time while sprinting between untrained and trained runners?

    Writing a paper looking at the acute differences between performing repeated sprint training on sand vs grass.

    Satish Verma · Exercise Fitness & Health Alliance, India

    Dear Kristian,

    Please refer to the following study by J. Santos-Concejero, et al for your querry:

    Link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3944563/


    Prof. Verma

  • Debabrata Phukon asked a question in Ectoparasites:
    How do I quantify the transmission of ectoparasites in group living/ colony-nesting birds?

    I have worked on the prevalence of ecto-parasites in livestock-wildlife interface before but couldn't quantify the transmission due to resource and time limitation. In a new study I would like to quantify the transmission of ectoparasites like lice and fleas amongst colony-nesting birds like Asian Openbill, Darter, etc. How do I go about it?

  • Anders Barlow asked a question in UHV:
    Anyone have experience using open source SPM software like GXSM with controllers from SoftdB?

    We have an RHK UHV SPM head that we want to revive but have no electronics. We are investigating options currently and have considered the R9 controller from RHK. We also have in our lab an Omicron SPM CU from a Nanoprobe that will apparently control the RHK.

    We are interested in open source software however, specifically GXSM, using hardware controllers from SoftdB, the MK3-PLL and the MK3-HV1.

    Does anyone have any experience using these controllers?

    How about the R9 controller? Is there anything that sets this apart from other controllers from companies like Veeco/Omicron/Bruker etc...?

  • Can new rifts start in the interior of oceanic plates?

    Does anyone knows a case of a rift that started in the interior of an oceanic plate, far from the plate boundaries ( thus excluding backarc basins)? Would that be mechanically possible?

    Joao C. Duarte · Monash University (Australia)

     Hi Adrien.. Many thanks! It looks very interesting indeed. I will dig in. Cheers

  • What is the difference between racism and ethnic discrimination?

    Before answering my question. Kindly read my explanation first.

    Base from two books i read, i conclude that:

    There is no difference between those terms. Ethnic Discrimination is the synonym of Racism.

    Below are my explanations and sources:

    From a book titled "Race and Ethnic relations" published in 2012 by Merger 

    The term Race is hardly use in the research field nowadays. Researchers prefer to use Ethnicity instead. Hence there is no difference between Race and Ethnicity

    In the past, there are difference between and race and ethnicity. Expert usually based different race by the difference of phenotype such as skin color, hair color or shape of the nose. While ethnicity is more into social and cultural category, for example certain kind groups who has the same behaviour consider to have their own ethnicity.

    Later , confusion start to develop to draw fine distinction between race and ethnicity. Below are the paragraph i quoted from the book.

    “As Biologist Daniel Blackburn (2000) as explained, all of the popularly used physical features to define races show gradients of distribution within population groups within which sharp distinction cannot be draws. Despite obvious physical difference between people from different geographic areas, most human genetic variations occurs within population. Michael Bamshad and Steve Olson have explained “individual from different population are, on average, just slightly more different from one another that are individuals from the same population.”

    In the last part of the section the author of the book find a subtle way to settle these confusion.

    “Because of its confusing usage and its questionable scientific validity, many sociologist and anthropologist have dispensed entirely the term race and instead prefer ethnic group.” 

    From a book titled "Racism and Ethnic Discrimination" published in 2011 by Lentin page 84

    "Racism becomes a catch-all phrase that can be used to describe almost any situation. It is used to refer any situation of discrimination or unfairness"

    That is all my explanation and sources. I assumed that these terms are the same and the confusion between the two is because maybe some researches still use the old definition and do not follow the update of this topic.

    i am asking this because i am doing my research on this topic and need feedback from other people. You are welcome to contradict my explanation. i would love to read it. However, please write the sources that you are using as the base of your statement.

    Thank you and have a nice day.

    Francesco Spagna · University of Padova

    In Italy anthropologists are engaged in the proposal to erase the word "race" from the text of national constitution: I think is a good idea. Along Cultural Anthropology an important distinction is between ethnocentrism and racism. In this sense racism can be conceived in the "strict sense": somatic differences used as a tool for discrimination or violence; if there are no somatic differences - as in the case of Hebrews during fascism in in Italy or Germany  - they are invented, produced in the imaginary. 

  • Andreas Arnold added an answer in Thyroid Cancer:
    How do you follow patients with papillary microcarcinoma?

    I want to present my patient who is 65 years old female and did not have any RT exposure or any risk factor before. Preoperative thyroid ultrasonography revealed 3,5 cm single solid hypoecoic nodule on left thyroid lobe .She undergone left lobectomy and pathology report confirmed papillary microcarcinoma. How could yo  follow this patient?

    Andreas Arnold · Inselspital, Universitätsspital Bern

    For a solitary, intraglandular papillary microcarcinoma (<10mm) without suspected lymphnode metsatses and without prior neck irradiation, hemithyreoidektomy is oncologically sufficient.

    If a follow up every 6 months is accepted by the patient, US with Doppler is an excellent modality for the remaining thyroid as well as for the lymph nodes.

    Otherwise totalisation should be performed.

  • Does/should the principle of “primum non nocere” (first, do no harm) support universal academic consistency?

    It is well known as a principle of medical ethics, but there are other contexts as well, since it has to do with principlism and moral decision-making even within pluralistic environments. Nonmaleficence is directly related to beneficence and contributes to the spiritual dimension of health. The question is how many disciplines are really engaged ….

    The degree of difficulty conceived in any program evaluation of student’s knowledge of
    professionalism and of professional behaviors; is the felt need to define universal features of professionalism “primum non nocere” or “patient interest above personal interest”.

  • What is distribution of partial sum in Poisson's Binonomial distribution ?

    Binomial Distribution:     C(M,N)  p^L (1-p)^(M-N)

    Poisson's Binomial  Distribution (PBD) : p_i  are different 

    Hyper geometric  :   Prob ( n success in m trials, given N success in M)

                              = C(m,n) C(M-m,N-n)/ C(M,N)

                              = distribution of  partial sum (up to m)

    Q. What is the distribution of partial sum for  PBD ?

  • How do I take care of mice recovering from ICV injection for subsequent behavioral tests?

    Hello: I'm planning to do ICV injection on mice (with amyloid-beta peptides for Alzheimer's disease), the dosage should be somewhere around 3µL. I'm not sure if the procedure would cause too much stress in the animals since they would be put in behavioral tests later. 

    How long should I let these mice recover and are there any tips on the recovery process? Thanks in advance!


    Nilesh Sudhakar Ambhore · JSS College of Pharmacy

    Hi Lin,

    I fully agree with above answers but, the use of mice model for surgery is little bit difficult due to high rate of mortality. I did the same study so as per my experience i would suggest you its better to go with rat model. Because the chances of mortality will be less and recovery will be fast.

  • John Sum added an answer in Data Clustering:
    Is there an absolute standard for clustering, like correctness for classification, to evaluate the quality of a clustering result?

    hello, everyone. I am puzzled, is there exist an absolute standard for clustering, like correctness for classification, to evaluate the quality of a clustering result? ps, I have no human labels for the dataset. Thank you!

    John Sum · National Chung Hsing University

    How many clusters in the data set is yet another open problem. For 2D, 3D data, we still can visualize and guess. For high dimensional data, it is hard.

    If the data has been labelled, it means that the number of clusters is already known. If they are not labelled, it will be difficult. 

  • Daniel Perdiz added an answer in OPA1:
    Is it possible to conclude about mitochondrial fission basing on phosphorylation of DRP1 and TEM images?

    I would like to assess whether my experimental protocol affects mitofusion/mitofission rate in tissues in vivo. I prepared immunoblots with antibodies against phosphoDRP1. I also plan to prepare TEM images of mitochondria to observe their morphology. Should I try to look at some other markers (e.g. OPA1)?

    Daniel Perdiz · Université Paris-Sud 11

    Ok. In my opinion, no reports describe phosphorylation at ser616 during heat shock. So ser637 is the good choice!

  • Britta Gossel added an answer in Social Science:
    Does anyone have examples of the consequences for methodology of constructivist organization research?

    I am looking for examples of methodological consequences/ use of empirical methods in the context of organization research based on constructivist epistemology. Can anyone support me?

    Britta Gossel · Technische Universität Ilmenau

    Hi Friethiof, that sounds good. Thanks a lot! Best, Britta

  • Which painter is, in the history of art, the most used geometry (mathematics) in his work?

    Is it Wassily Kandinsky (1866 - 1944) or someone else?

    Christopher C Rout · University of KwaZulu-Natal

    Dear Djoko

    What do you mean by "used"? Do you mean the painting contained mathematical or geometric images or do you also include the use of mathematics and geometry in the design of the painting?

  • Maria Habib added an answer in Thermal Cycler:
    Is anyone using life technologies SYBR green master mix on a Roche real time PCR machine (LC96)?

    Hi there,

    I am using  Life Technologies SYBR green master mix (ABI) on a Roche real time PCR machine (LC96). I am having a lot of issues while standardizing my reaction conditions. If anyone out there is using same combination of thermal cycler and Sybr Green, please let me know.

    Maria Habib · Jamia Millia Islamia

    Dear Dr. Prabhu

    Thank you so much for your help. here are the answers to your questions:

    1) No my PCR does not require an ROS dye

    2) Yes i did check the cycle temperature. And the same temperature at which the primer annealed in normal PCR was taken for real time also.

    3) I am using Sybr Green Assay

    4) I am doing Relative Quantification.

    5) I have deselected ROS Reference dye option.

    6) Yes i am using B-Actin as well as GAPDH as reference.

    7) Yes. I did use NTC.

    8) Beta Actin and GAPDH

    9)  The ct value for NTC comes to be in between 30-35.

    10) The Roche LC96 analysis software has auto ct mode only. 

    I have been using reported Primers till now. A couple of people have also advised me to design another set . As i had a tough time standardizing the annealing temperature.

    I am quite worried about the fate of this experiment owing to delay in standardization..

    I will be forever grateful for your help.