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  • Grace Solomon-Wisdom added an answer in Exhalation
    Has anyone came across a study on the composition of exhaled air during exercise

    I mean, of course, the presence of exhaled gases other than oxygen and carbon dioxide.

    Grace Solomon-Wisdom · University of Sussex

    Do you mean volatile organic compounds (voc)? In normal human exhaled air, it is 3.4-9.4%. It has been shown to differ significantly in cancer patients (about 50%). The composition and type of  VOC differ in such circumstance too.

  • Debi S. Saini added an answer in Writing
    What you write in a memoir?

    What you write in a memoir. What is the experience and memories you want to share. What is important about what you want to tell.

    Debi S. Saini · Management Development Institute Gurgaon

    I think it will include the following:


    --Parents & Siblings

    --Schooling & Higher education

    --Your teachers

    --Values inculcated


    --Role models

    --Your Vision

    --Nostalgic events

    --People who mattered

    --People who blocked you and why

    --How you look at your past life 

    --How you dealt with difficult time in your life

    --Messages that should emanate from them for the reader--this should be kept in mind and so titled

  • RNA extraction form human tissue

    can anyone suggest a protocol for extraction of RNA from human tissue?

    Reyhaneh Ravanbakhsh · University of Tabriz

    Dear Haritha Doddam Reddy
    As John Hildyard mentioned, we need to know some information about your tissue and .... but I share protocols that I usually use them for extracting RNA from breast , thyroid& colorectal tissues (RNX plus kit & TRIZOL kit)
    TRIZOL kit procedure:
    1. At first, freeze tissue samples immediately upon collection.
    2. Add 1mL TRIZOL kit per 50-100 mg of tissue.
    3. Homogenize tissue using a glass-Telfon for 5 min.
    4. Incubate the homogenized sample for 5min at room temperature (20-25 oC)
    5. Add 200 microliter of chloroform per 1mL of TRIZOL.
    6. Shake tube vigorously by hand for 20 sec.
    7. Incubate for 5 min at room temperature.
    8. After incubation, centrifuge the sample at 12,000 xg for 15min at 4 oC.
    9. Remove gently the aqueous phase and place it into a new tube.
    10. Add 500 microliter of 100% isopropanol (4-7 oC) to the aqueous phase .
    11. Incubate it at room temperature for 15min.
    12. Centrifuge at 12,000xg for 15min at 4 oC.
    13. Remove and discard supernatant from the tube and wash the pellet with 1mL of 75% ethanol.
    14. Centrifuge the tube at 7,500xg for 8 min at 4 oC.
    15. Remove and discard supernatant from the tube and dry the RNA pellet for 10 min at room temperature.
    16. Resuspend RNA pellet in RNase-free water or DEPC water by passing the solution up and down several times through a pipette tip (amount of water(10-50microlitter) is dependent on pellet size).
    17. Store RNA solution at -80 oC.

  • Nashon Adero added an answer in Waste
    What according to you are the factors that affect the placement or location of a waste collection bin?

    I want to collect your views on this.

    Nashon Adero · Oakar Services Ltd

    Proximity to the sources of waste such as recreation parks, social amenities, e.t.c..

    Visual intrusion - must not be in a place where it distracts the continuity of the visual appeal of the surrounding

  • Henrik Rasmus Andersen added an answer in Biofilms
    What is a good biofilm media for supporting healthy, aquatic biofilms?

    I am currently working with biofilms to remove P and carry out nitrification within aquatic systems. We are currently trying to chose a biofilm media to support the growth of healthy biofilms, which is proving more difficult than we originally thought. 

    Here is our criteria: 

    - Must have very high SSA (specific surface area)

    - Must be chemically inert (i.e., not alter pH or release any chemicals into the water).

    - Must be relatively easy to get hold of in large volumes.

    - Must be relatively cheap to purchase. 

    We are ideally looking for porous beads, but are having difficulty finding ones that may be usable. 

    Any tips/advice/help would be much appreciated.



    Henrik Rasmus Andersen · Technical University of Denmark

    The media I suggested is intended to be used in suspension. Look up MBBR. This is much more cost and size effective than building a filter. With suspended biofilm you do not have the need to backwash as the movement continuously scrape the excess biofilm from the surfaces.

    It sounds like you intend to make a trickling filter type of treatment, but this is regarded as outdated in the wastewater treatment industry and they are rarely constructed anymore. The problem is mainly the stability of treatment performance and the high energy cost for nitrification.

  • Is it necessary to remove cyanide from cassava peels before taking it through dilute acid hydrolysys for subsequent bio ethanol production?

    I was wondering if it was necessary to remove the cyanide present in cassava peels before applying dilute acid hydrolysis as a pretreatment step. In addition, if it is neccesary, can I please get suggestions on how to remove the cyanide before hydrolysis. Thanks.

    Andrew Amenaghawon · University of Benin

    Thank you very much for your responses

  • Saranya Ram asked a question in LCR Meters
    How to model the Cp-V characteristics of an organic solar cell using parametric analyzer or either with LCR meter?

    How to measure (model) the Cp-V characteristics of a typical organic solar cell ?

  • Can anyone suggest some Cereal-based infant formulas?

     Cereal-based infant formulas

    Rathnaprabhu Sudha · Independent Researcher

    rice mashed and bengal gram .

  • What criteria should be used for grading undergraduate students' research project?

    At the onset of our nursing programme, we gave room for the supervisors to grade their students' research project and award a score for it. This usually formed 20% of the total score for the project. An external assessor is also invited to grade the same research projects & award a score to the candidate for the oral presentation as well as the book, which constitute 80% of the total score. Right now we are in the process of revising our grading system for the undergraduate research project. Is it advisable to retain the 20% supervisors' score or allow the external assessor to grade the students' project over 100?. What is the practice in other countries?  If the practice is to be retained, what are the best criteria to be used by supervisors for assessing students'  projects?

    Ian Kennedy · Independent Researcher

    In Engineering we would mark the report as forming 80% and the oral as 20%. The external examiner would confirm (or deny) our marks (not remark), using the oral especially when the report was a borderline case. 

  • Can anyone help with NGS data analysis?

    Hello everyone

    I am doing NGS and I have ha huge amount of data that I have to analyse,now. I tried CLC- genomic workbench for the analysis and than Ensemble VEP for annotation. But I am looking for a more reliabel worklflow to analyse my data and find the needle in the haysack, a disease causing mutation. Does anyone has an idea for a pipeline or a worklflow or knows good prediction tools (except mutationtaster and ensemble VEP)? I did sequencing on a Illumina Plattform and resequencing. I made a capturing so its less than whole exome sequencing (exones of 150 genes).

    I really hope that there is someone who is experienced in that field an will help me!

    Thank you!

    Afagh Alavi · University of Tehran

    Dear Yaba

    I think you need an online software for .VCF files analysis. You can use FunSeq software.


  • Does anyone have experience in Statistics: Network of associated variables (key-words: Pearson, spearman, correlation,R software) ?

    Hello everybody,
    I am biologist and I have a question that concern network that are built on matrix of correlation.
    I have almost around 15 quantitative variables that I measured at different time points (age of animals).
    I have used an automated pairwise spearman correlation test between the quantitative variables. I'd like to build from this matrix of correlation a network of significantly correlated variables where each node is a variable at one age.
    Do you know how to do that? Which kind of analysis should be used?
    Thanks for your response

    PS: I use R software for data analysis. So advisements on packages that could be used for my problem are welcome.

    Alessandro Ferrarini · Università degli studi di Parma

    it's a common system of ordinary differential equations




    By the way, passing from correlations to causal links is not an easy task. In facy correlations among variables are the final results of initial causal links. So what you want to do is going back from a final static situation to a backward dynamic one

  • Ahmed Abd El-Gawad added an answer in Citations
    The importance of "Real" Impact Factors of journals

    The Impact Factor (IF) of the Plant & Soil Journal has considerably increased from 2.638 in 2012 to 3.235 in 2013. For those researchers who are familiar with IF, it is a great deal and achievement that implies different issues.

    1) In recent years several journals have gained an "Unreal" IF through manipulation such as publishing a large number of Review Papers or asking the authors to cite the published papers of those journals even where not that relevant. I myself have experienced such suggestion from an Editor of a journal but I did not do it because I believe that it is not ethical since it would mislead the prospective authors about the real value of that journal.

    2) IF greater than 3, mainly in agriculture and soil science disciplines, means that the journal has a great impact on developing new science. Therefore, they attract researchers who are seeking for breakthrough studies that have something valuable to say. I have been reading the paper of Plant and Soil and strongly believe that it deserves such great and REAL Impact Factor as the papers are very new and breakthrough as far as I follow those in my field of research. So, I congratulate the Editorial board of this journal and hope for continuous improvement of this prestigious journal.  

    3) In recent years, some journals that have experienced increased IF claim that they have a higher rate of rejection of manuscripts. Although it is a good practice to just publish those manuscripts that are of high value, the Editors should be more careful to not reject some of those that are worth publishing. Recently a number of journal's editor make a first and quick screen of the manuscript and reject the manuscript without sending them for peer-review processes. It is fine that they want to keep the IF high but it is another kind of manipulation to increase the IF in the expense of rejecting author's paper that might get through publication after getting positive responses from the reviewers.

    4) Another journal biometric index that is getting more popular is Source Normalized Impact per Paper (SNIP) that measures contextual citation impact by weighting citations based on the total number of citations in a subject field. Although it is not reported for Plant and Soil, it seems that SNIP would be high for it since this journal is a specific-oriented journal and has its own readers. So, overall, Plant and Soil would be keeping its role as a reliable forum for publishing papers of high value especially in plant root studies. 

    Ahmed Abd El-Gawad · Mansoura University

    I agree with dr Hector

  • Janis Locs added an answer in Calcium Phosphates
    How to solubilize Biphasic Calcium Phosphate?

    How to solubilize Biphasic Calcium Phosphate?

    Janis Locs · Riga Technical University

    Increase the surface area, meaning porosity or decrease particle size.

  • Manish Kumar added an answer in PM2.5
    What could be the possible reasons for poor correlation between AOD and PM2.5?

    Usually there exists a strong positive correlations between AOD and surface PM2.5. but if it is poor, what factors might have played role? 

    Manish Kumar · Banaras Hindu University

    Dear sir, you are right. there were a number of days with dense fog during the study period.  however, we did not study the diurnal variation because we have monitored PM mass concentrations through fine particular sampler continuously operated for 24 hrs. I think this could be one of the reason behind this discrepancy. But sir as we had studied under those given conditions and resources and found such results, should we report it for publication by mentioning all the limitations and circumstances? 

  • Irina Pechonkina added an answer in Labour Law
    What are the new values needed to be imbibed in labour laws of countries today?

    In most countries labour laws have been traditionally built on the logic of exploitation of the weak by the strong. Thus, labour creates adversarial relations between the employers and the employees. These days, business can not be done without the cooperation of the employees, as employers compete in the product market on the strength of their talent's engagement. Therefore, advocates of workplace cooperation talk of new values to be imbibed in the philosophy of labour law. What do you think can be these new values or thinking so as to be in consonance with the current time.

    Irina Pechonkina · Math and Physical Lyceum

    You are absolutely right- legality-enlightenment-satiety.

  • Chitra Joseph added an answer in Brand
    Which company/brand provide the good quality and economic PCR Master Mix?

    I want to purchase the PCR Master Mix for my research. Can you suggest me the type of PCR master mixture I should use and which company/brand provides it at suitable cost. Does anyone have experience of working with EmeraldAmp Max PCR Master Mix 160rxn from Takara?

    Chitra Joseph · Sankara Nethralaya


    I have been using Emerald PCR master mix from takara and am very satisfied with this product.Its easy to set up and you can directly load to gel for visualizing your bands as it is prestained.You get neat distinct bands provided your pcr conditions are correct.

  • What do you think about an equation to precisely predict happiness?

    BBC report says scientists have developed a mathematical equation that can predict momentary delight. They found that participants were happiest when they performed better than expected during a risk-reward task.
    "We can look at past decisions and outcomes and predict exactly how happy you will say you are at any point in time," said lead author Dr Robb Rutledge from University College London.
    What is your opinion about this research? Now that we have an equation which can we use it in survey research to replace a Likert scale for such questions? Any further comments will help. Thanks.

    Robb B. Rutledge, Nikolina Skandali, Peter Dayan, and Raymond J. Dolan - A computational and neural model of momentary subjective well-being, August 4, 2014, doi:10.1073/pnas.1407535111

    Hashem Adnan Kilani · University of Jordan

    it is an interesting discussions and philosophical thoughts. I would add this:

    Happiness is to enjoy the pleasure of others and share their happiness, that is formulated as: 
    Successful business + given much + smiled in the face of your brother + love to others as you love yourself+ trust in yourself / Do not hate others.

  • Is it possible that a tumor suppressor gene promote cell proliferation?

    I am working on a novel candidate tumor suppressor gene. Its expression  is significantly lower in tumor that that in paired non-tumor tissues and is silenced by promoter methylation in cancer cell lines. But it significantly promote cancer cell proliferation when restoring its expression in vitro. We repeated several times using different cell lines. That is case. what is wrong? Thanks!

    Xiangning Zhang · Guangdong Medical College

    If the molecule is confirmed as a tumor suppressor, it should not promote cell proliferation.  But sometimes,  a cancer related gene could behave in a context dependent manner, for example, tumor suppressor in one type of tissue, and a transforming gene in another type of tissue.  Giving an example of TNFRSF19 on chromosome 13q12, two Chinese teams have been published in Nature Genetics that the locus harbors a susceptible gene for different tumors, which contributes to the genesis of nasopharyngeal carcinoma and lung cancer in a loss-of-function manner, but the study from a North African lab suggested that it is an oncogene.  The finding has been seen with other genes.  Moreover, a tumor suppressor gene from chromosome 3p21, HYAL2 manifests asymmetric tumor suppression, that is, it suppresses tumor formation in vivo but not in vitro.  You could produce good result if elucidating unexplained data.  Good luck!

  • Neonatal peripheral blood vs. cord blood: are they the same? Do results of cell studies in cord blood reflect what is happing in peripheral blood?
    Are there any differences between umbilical artery and umbilical vein blood in term of profile of cell phenotype?
    Rathnaprabhu Sudha · Independent Researcher

    Neonatal blood is physiologically different from Cord blood . Cord blood will reflect only fetal physiology while neonatal peripheral blood will reflect purely neonatal status and right from cells , biochemistry ,hormonal components  all  will be totally different in fetus versus neonates .

  • Bruno Quendera added an answer in Neuroimaging
    What are the currently available best systems for color calibration in the MR environment?
    Most systems are not MR compatible.
    Bruno Quendera · University of Coimbra

    It's possible to measure the color conditions in bore if magnetic field is turned down (it a risky procedure rarely made in maintenance and with an high possibility of quench) in the same conditions as during experiments but without damaging the spectrophotometer.

  • Unknown Line shape noise in Laser Scanning Microscopy

    This is the microscopic image of rat tail tendon with custom built Second Harmonic generation Laser Scanning Microscopy, (photon counting with Hamamatsu PMT modules)
    But there were random-spread line-shape noises over image.
    Which point should I examine first to get rid of that kind of noises?

  • Tomas Chrudimsky added an answer in Buffer
    TE Buffer vs Phosphate Buffer in DNA dilution.

    Would it make any trouble if I we use phosphate buffer instead of TE buffer in diluting Nucleic acids?

    If I am correct, phosphate buffer is used typically to maintain the viability of live cells. On the other hand, TE buffer preserves the integrity of DNA samples. 

    Tomas Chrudimsky · Academy of Sciences of the Czech Republic

    Phosphate buffer just holds correct pH. TE buffer, i addition inhibits DNAses thanks to EDTA. I agree with Amr T. M. Saeb - my favourite solution for DNA elution is pure deionized water.

  • Johan Börjesson added an answer in Materials
    Does the sublattice of the last solidified secondary phase in inter-dendritic regions in an Ni-base super-alloy create anisotropy in the ductility?
    It is well known that the ductility in Ni-base materials is correlating to the volume fraction of any secondary phase. This relation is however assuming a random distribution of the secondary phase. If this phase is formed in the inter-dendritic and last solidified regions, they should have a non-random distribution since the dendrites have some type of regular pattern in 3D. If the secondary phase then have a regular pattern in 3D, it can form a sub-lattice that could be anisotropic in 3D. Would it then create a anisotropy for the ductility?
    Johan Börjesson · ESAB AB

    Thanks Bob!

    My case involve solid solution strengthen Ni-base weld metals were you get directional structure in each weld bead. The second phase particles in the last solidified parts in this case are different types of metal carbides, depending on alloy.

    I don´t find any good explanation of this mechanism in the literature, but it might be that I didn´t look in the area of casting and that is "old" knowledge that you don´t find in papers anymore, more in textbooks.

    Do you happen to know (on top of your head) any good place in the literature where this mechanism with the second phase particles give rise to the anisotropy is explained?


  • Kam W Tang added an answer in Ice
    If the polar ice caps would melt more, resulting in an erection of the underlying landmasses, would not this accelerate the elevation of sea levels?

    The polar ice caps rely on continental masses sinking them into the earth's crust. If the ice melts quickly, did it would not occur a sudden acceleration of the sea level elevation (estimated at 37 cm by the end of this century).

    Kam W Tang · Swansea University

    The basic idea is that continental ice cap weighs down the Earth's crust. When the ice cap melts, this weight disappears and the crust rebounds, resulting in an apparent *decrease* in sea level (i.e. elevation of the land mass)--- this is called isostatic rebound. 

  • Is there an existing work concerning the (global) controllabity of nonlinear systems at most affine in state (dx/dt=A(t,u)x+B(t,u))?

    But non linear with respect to the control?

    Fotsa Mbogne David Jaures · University of Ngaoundéré

    I encounter some difficulties in the exploitation of  the attached documents. Is it possible to have more precise (english) references? Thank you all.

  • Onur Elmas asked a question in Kit
    Photometric hemoglobin assay without any kit.

    Is there any method for photometric hemoglobin assay without any kit?

  • Mehran Khayyam asked a question in Vaccination
    What is the vaccination schedule in ostrich?

    What is the vaccination schedule in ostrich?

  • Why neutrons in valence shell don't decay?

    Should not they be decayed? Waiting for help.

    Saeid Soheyli · Buali Sina University

    We can determine the stability ratio of N/Z  for every isotope family. This quantity is approximately 1 for light nuclei and increase from 1 for heavy nuclei. Therefore, if the N/Z of a member of isotope family is greater than the neutron-to-proton ratio of stable members, this member can decay by beta emission. Mean field is introduced for simplicity in single particle independent shell model in which  properties of a nucleus such as spin, parity, quadruple moment and etc.,  can determine by the properties of  latest odd neutron and/or  odd proton. It is obvious that the beta decay is forbidden for the stable nuclei in an isotope family. It can justify by several considerations such as the nature of interaction, Pauli principle and etc.. 

  • Marcus Dejardin asked a question in Websites
    Do you know the NEP mailing lists and NEP-Entrepreneurship in particular?

    If not, please check the NEP website: http://nep.repec.org/ 

    "NEP is an announcement service which filters information on new additions to RePEc into edited reports. The goal is to provide subscribers with up-to-date information about the research literature. Our success in achieving this goal has been substantial. Today, there are 74451 subscriptions from 33378 unique addresses distributed throughout the world."
    Reports include abstracts of listed new Working Papers + weblinks for direct download!