Q&A

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  • Mohan Cm added an answer in RNA Gel Electrophoresis:
    Is it ok to use DNA molecular weight marker in RNA electrophoresis? Or only RNA molecular weight marker should be used to see RNA integrity?

    Is it ok to use DNA molecular weight marker in RNA electrophoresis? Or only RNA molecular weight marker should be used  to see RNA integrity?

    Mohan Cm · Indian Institute of Technology Guwahati

    If your aim is to just check the RNA integrity, markers are actually not needed. Resolve the samples under denaturing conditions (formaldehyde agarose gel) and check the ratio of intensity of upper rRNA band  to that of lower rRNA band. The ratio should be near to 2.

  • Shane douglas Muldoon added an answer in Grounded Theory:
    Have you come across any studies where Grounded Theory and Case based method was used together?

    I am doing my doctorate. The nature of my problem required me to gather bounded project cases (with proper problem statement, options and resolution in each case). Over 100 in-depth interviews I have conducted are all bounded projects. I am using grounded theory for driving my data collection with theoretical sampling. Coming to data analysis, I am using constant comparison method between interviews. I am wondering if here multiple case studies based analysis is also applicable. Have you seen any such study in which Grounded Theory and case based analysis was used together to form the theory? Please provide some guidance and references.  

    Shane douglas Muldoon · New Age People Research Consultancy, Melbourne, Victoria, Australia

    ok now, from memory (I dont have their text to hand) I recollect that glaser and strauss in their original exposition of GTM clearly stated that they did not wish to be prescriptive in the use of GTM and I certainly have not been in my work. go Arnost! go Raman!! argue the toss with purists who get stuck with their favourite, well trod methods and methodology. sometimes I think laziness of thought or lack of boldness of thought and adaption fear is at the root of some critiques. btw, to share a little about PhD EXAMINERS, one of mine had critiqued that I had not explained a key measure - I had to politely point out the entire section in the methodology chapter that did so (I put it down to the examiner reading my thesis late at night having consumed too much port!). good luck folks.

  • Koushik Roy added an answer in Shellfish:
    Is allergy a real issue in chitosan from shellfish origin?

    I am having difficulties in finding scientific data on this topic.

    Koushik Roy · Central Inland Fisheries Research Institute

    In the light of your present hypothesis, I would like to draw your kind attention in investigating the cases of accumulation of carbamate toxins like saxitoxins (responsible for paralytic shellfish poisoning) in chitosan which is possibly a part of the intrinsic depuration process possessed by many shellfishes. This might strengthen the concept as well as the conclusion which you are focusing on.

  • Dr. Muhammad Sajjad asked a question in Electrical Field:
    Negative value of electric field gradient?

    What does it mean if the value of Electric Field Gradient is negative?

  • Carlo Bianco added an answer in Micrographs:
    There is some software that can measure the % of empty spaces in a micrograph image?

    I have some micrograph images from meat fibers and want to measure the % of this image that is filled by fiber and the % of empty spaces. 

    Carlo Bianco

    You can use Imagej, you can measure the minimal feret diameter of myofibre (crosss etion) that is a nice indicator, using the analyze particles analysis in Imagej. On youtube there are tutorials, or you can go to the Imagej-fiji homepage. In my opinion adding the diametre of myofibre to your research could enrich the dataset and the biological meaning, a preliminary minimal procesing of images is required, if you work on H&E sections.

    regards

    CArlo

  • Taher Rabizadeh added an answer in 31P MRS:
    What kinds of information can 31 P NMR give me?

    Hi,

    I would appreciate if you could guide me about 31P solid states NMR analysis. I want to measure the P adsorption on calcite crystal (I add P as additive to the crystals precipitation solution and see surface modification).

    What kinds of information solid states NMR can give me? I mean,

    can it tell me binding between P-Ca and strength of the bond?

    amount of P adsorbed?

    configuration of P on the surface

    or it just will tell me there is P or there is not. 

    Can it say P is on the surface or it has incorporated to the crystal structure

    Regards,

    Taher Rabizadeh · University of Leeds

    Hi, Thanks for your useful information. The additives that I want to investigate their effects are mentioned below. But if I see P peak by SSNMR, then can I distinguish whether it is from P adsorbed to the surface or P incorporated to the structure?

    BHMTPMP     Bis(HexaMethylene Triamine Penta (Methylene Phosphonic Acid))

    1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP)

  • Eric Guiheneuf added an answer in Fats:
    I need to filter bone marrow specimen before sampling on a Hematology Analyzer. Which is the better system that allows to recover more material?

    In bone marrow samples some fibrin filaments or micro blood clots as well as fats particles may interfere in cellular counting. A pre-filtration can prevent these interferences

    Eric Guiheneuf · Centre Hospitalier Universitaire d'Amiens

    You can use cells strainers like this. In our lab we use 100µm strainer for bone marrow before sampling on cell counter.

  • Mario Vincenzo Russo added an answer in Superstitions:
    Is there room for religious thoughts in a scientific mind?

    Two of my previous questions were on the influence of emotions and/or  of superstition, on a scientific mind.

    Many of the answers we got were absolutely surprisingly unique and brilliant.

    I thought that we should go on, towards thr definition of a m,ore complete scientific mind. 

    Should scientists only use their pragmatism in problem solving, or can they use their intelligence in broader views of the World?

    Mario Vincenzo Russo · Università degli Studi del Molise

    In my mind I think there's enough room for both for religion and for science. They are on two floors totally different and non-overlapping and therefore do not contradict each other. This helps me a lot in the choices and decisions of ethics and morals as they are convinced of my faith.

  • Nupoor Prasad asked a question in Caco 2 Cells:
    For Inflammatory Bowel Disease study which passage of CaCo-2 and how many days grown cells should be use as IBD model?

    I want to know that which passage of CaCO-2 can i use as IBD model and method for its differentiation?

  • Mohammad Nasir Uddin asked a question in Cryosectioning:
    How can I prevent detachment of retina from choroid during cryostat sectioning of human optic nerve head?

    Hi, in my project I am doing cryostat sectioning (Longitudinal section) of human optic nerve head. In cryosection, I have to keep all the three layers (retina, choroid, sclera) attached together but after cryosectioning I find the retina detached from choroid or huge gap between retina and choroid. I think this problem might be due to embedding problem because when I embed the tissue in OCT medium I can’t keep the retina completely attached to choroid. It would be highly appreciated if you have any suggestion to solve this problem.

  • Sioned Warrell added an answer in Emergency Response:
    What applications are out there to assist emergency response personnel during Mass Evacuations?

    I am currently looking at computer based applications that can help emergency responders during mass evacuation, to record their actions and provide real time data on the evacuation and the progress being made.  I am currenty looking for alternatives to a modified EXODUS package.

    This is not my area of expertise and is a time dependent project and any insight/signposting provided by 20 August 2015 would be gratefully received  

    Thank you!

    Sioned Warrell · South Wales Local Resilience Forum, United Kingdon

    Thank you both for taking the time to repond, I really appreciate it. I will take some time to look at these early next week. I hope you both have a good weekend.

    Kind regards

    Sioned 

  • Ibomcha Ngangom asked a question in Arbuscular Mycorrhiza:
    Hello everyone! is there any specific media for VAM multiplication?

    VAM: Vesicular arbuscular mycorrhiza is symbiotic associated fungus to plants root which enhance the growth of plants

  • Carlo Bianco added an answer in Intradermal Injections:
    Is it better to do intradermal injections using the ear or shaved abdominal/thigh region of mice?

    Dear all,

    We deliver DNA vaccines into the dermis of mice ears routinely, but I wonder whether delivering intradermal injections to shaved abdominal or thigh regions would be more immunogenic. I have not done a comparison of this nature and therefore would like some advice from any of the smart people here who have experience regarding this matter. If you also have any advice on the most reliable way of delivering vaccines or any immunogenic material via the intradermal route (even to the ear), that would also be much appreciated.

    Carlo Bianco

    Hello,

    an important issue in my opinion is the site also for the induction of mucosal immune response. A vaccination in the head region could putatively be more effective in inducing also a galt immune response, due to the drainage of antigens by cervical lymphnodes, while a vaccination in the abdomin al area could be more beneficial in eliciting a reproductive malt immune repsonse.

    regards

    Carlo

  • Hafiz Muddassir Riaz added an answer in Opioid Analgesics:
    Are you aware of the record duration of use of intrathecal morphine in a patient with refractory pain control?

    Are you aware of the record (longest ) duration of use of intrathecal morphine in a patient with refractory pain control?

    Hafiz Muddassir Riaz · University of Health Sciences Lahore

    yeah, It also made me surprised about this, but when i got further details, the patient did regular exercises and avoided undue stress . according to him,  this problem made me bed ridden for few weeks but now I am living normal life, "

  • Chun Liu added an answer in Attitude:
    Should we as teachers try to change our students or should we change ourselves?

    Values, attitude and thinking of students has changed a lot since we were students. Are their ways as correct as ours were, or are they wrong? Should we mould ourselves or should we try to change them?

    Chun Liu · Prehistoric Archaeology

    Dear all

    Mutual adapting

  • Manan Vishvas Desai asked a question in Proteins:
    What would be an effective parameter choice in molecular dynamics for studying helix-coil transformation?

    I wish to study helix to coil transformation in a protein when its unbound and when it interacts with other proteins. For molecular dynamics what would be  an effect parameter choice for such study. Currently i am considering an implicit solvent MD approach however, would mesoscopic/reduced model or Go-like model or any other approach be more preferred?

  • Noura S. Dosoky added an answer in Cell Adhesion:
    How long should I leave the 5637 cells in trypsin-EDTA?

    I'm growing 5637 cells for the first time. During splitting, I noticed that after 2 min in 1x trypsin-EDTA, the cells are still adhering to the bottom of the flask. Do I need to use a higher concentration of the enzyme or increase the reaction time?

    Noura S. Dosoky · University of Alabama in Huntsville

    Thank you so much for your help! After trying many times, I found that incubating the cells with 1x trypsin-EDTA for 15-18 minutes at 37C gives a good result. 

  • Caleb Gardner added an answer in Copulation:
    Are there any morphological indicators of female reproductive form (other than glair) in crayfish (Genus: Orconectes)?

    All the literature I have found on determining whether female crayfish are Form I (reproductive) or Form II (non-reproductive) only mention glair, the presence of eggs, or the actual act of copulation. However, I was wondering if anyone knows of any other physical characteristics that might signal reproductive receptivity in females before the appearance of glair. For instance, I've noticed recently molted female O. rusticus have different coloration of the annulus ventralis/sperm receptacle compared to intermolt females. Any advice or suggestions appreciated!

    Caleb Gardner · University of Tasmania

    HI Sarah,

    No tried methods for crayfish from me but here's a few methods from other crustacean species that you may want to have a look at:

    - in southern rock lobster Jasus edwardsii the abdomen changes shape and becomes wider.  You could perhaps examine that with caliper measurements or 3D scanning also an option for more sophisticated measurements like volume.

    - "mating scars" have been observed in a few crab species like Scylla serrata and Pseudocarcinus gigas.  These are scratches or melanised marks around the gonopore.   The mating process is different for crayfish but perhaps worth a look.

    - non-lethal imaging methods for determining ovarian development may work.  I've used CT scanning for Pseudocarcinus but other options like ultrasound, X-ray and MRI may work??

    - in some species the haemolymph chemistry changes with lipid deposition - you may be able to see colour change on the underside of the abdomen, or else a sample taken by syringe.

    - biochemical from a haemolymph sample eg for  lipid levels or carotenoids.

    Good luck!

  • Harald G. Dill added an answer in Soil Survey:
    What is the best and most reliable soil database at the European level?

    Hi,

    There are quite a few number of soil databases being used worldwide, each having different spatial resolution, coverage, and data quality. Among them, the JRC ESDB, the FAO/Others HWSD, and the ISRIC-WISE databases are more cited. However, no specific set of rules have been developed to select an appropriate soil database.

    Do you have any suggestion for choosing the best and most reliable soil database for a research study at the European level?

    Behnam Ababaei/

    Harald G. Dill · Leibniz Universität Hannover - Institut of Mineralogy

    Dear Dr. Ababaei,

    I recommend to consult the following references to solve your pedological problems on a European level.

    Batjes N.H. (2008) ISRIC-WISE Harmonized Global Soil Profile Dataset (Ver. 3.1) Report 2008/02 ISRIC.- World Soil Information, (with dataset) Wageningen.

    FAO 1985 Global and national soils and terrain digtal databases (SOTER)- Procedures Manual . Worl Soil Resources Report 75 Rev 1 FAO, UN

    NRCS 1993 Soil survey manual-scetion 3 examination and description of soils

    http:// www.ga.gov.au/meta/ANZCW0703011055.html#status

    Best regards
    H.G.Dill

  • Mauro Doneddu added an answer in India:
    Tonna sp. confirmation...?

    Can anyone confirm the species for this Tonna? collected from the Gulf of Mannar, SE coast of India.

    Regards

    Deepak

    Mauro Doneddu · Independent Researcher

    It seems to be Tonna cumingii (Hanley, S. in Reeve, L.A., 1849)

  • Zainidin Eshkuvatov added an answer in Integral Equations:
    How can you determine whether a method of approximating the solution of an integral equation converge faster than another method ?

    The integral equations, especially the nonlinear integral equations can be solved only by using some methods for approximating of solution. Thus, for example, mention the method of successive approximations combined with a quadrature formula. The questions above have been formulated in this regard.

    Zainidin Eshkuvatov · Putra University, Malaysia

    Standard way of knowing faster convergence of the method proposed is that you can compare your method with other method for the same problem in terms of timing and accuracy.

    The best way of knowing the faster method than the others is the analysis the order of convergence and exactness of the method proposed. One of the faster method for Nonlinear Integral Equations in which I know is Newton-Kantarovich method together with Gauss-Legendre quadrature formula. 

  • Nupoor Prasad asked a question in Caco 2 Cells:
    For Inflammatory Bowel Disease study which passage of CaCo-2 and how many days grown cells should be use as IBD model?

    I want to know that which passage of CaCO-2 can i use as IBD model and method for its differentiation?

  • Nader Aghakhani added an answer in Health Surveys:
    Is the Short Form (36) Health Survey useful for every patients?

    The Short Form (36) Health Survey is a 36-item, patient-reported survey of patient health to measure of health status. I studied many clients by using this questionnaire. But I want to know that is tool is useful to calculate quality of life in all the patients or it is useful for some patients?

    Nader Aghakhani · Urmia University of Medical Sciences

    I think SF36 should be redesigned for each diseases.

  • Shuaib Khan added an answer in Excipients:
    Tablet thickness get increase in stability condition?

    We are facing problem with our formulation development. Our API is in oleoresin form which is granulated with carrier to form granules, than mixed with extrgranular excipients in order to compress.

    Compressed tablets appears good but after keeping them in accelerated stability conditions tablets thickness got increased. 

    Open for suggestions!

    Shuaib Khan · Himalaya Global Research Center

    Thanks Matthew .....Thanks Abhishek 

  • Vikash Gahlyan added an answer in Piping:
    What are the thickness and temperature limit for PWHT of ASTM 537 grade I and II material?

    We generally go for PWHT as per  ASME B31.1 (2007), Code for Pressure Piping, Section on Power Pipings. 

    Vikash Gahlyan · Larsen & Toubro (L&T)

    Thanku Very much sir @  krishnan for your valuable answer

  • Mohammed Eltoum added an answer in Remote Sensing and GIS:
    Does anyone have any literature on a procedure for multivariate geographic clustering approach in GIS?

    Mainly for eco-regionalization and for  delineating cells with same climate and geographical characteristics.

    Mohammed Eltoum · University of Khartoum

    Ecogeographical theory,analysis and applications

  • Alain Celzard added an answer in Polymer Composites:
    What are the tests to be done to determine the combustion behavior of polymer nanocomposite?

    I am expecting guidance from experts about how to analyse the combustion behavior of polymer nanocomposites and what kind of test should be done.

    Alain Celzard · University of Lorraine

    Cone calorimetry is among the best as it can not only measure the heat released during combustion for different values of radiant energies (very important to know), but it can simultaneously measure the induction time before the material starts burning and the weight loss during combustion. Some machines also analyse the composition of the fumes at the same time.
    Alain

  • Patrick Navatte added an answer in Risk Management:
    Are derivative instruments commonly used for risk management of sovereign debt?

    In the current sovereign debt market landscape, the portion of government securities on the national financing are so significant that may affect the respective countries' economy. Nonetheless, debt management offices are normally less capable in managing the associated risks of the portfolio or cash flow (in comparisons to the investment banks, for instance). In this regards, hedging strategy may help the countries to mitigate the risks and manage optimum portfolio risks. The question is: to what extent the derivative market/instrument can assist the government to manage the risks? Especially, what types of derivatives are normally being utilised? What type of risk management strategy is normally employed?

    Patrick Navatte · Université de Rennes 1

    Hi!

    Interest rate swaps are commonly used to try to lower the interest charges payed by the relevant state. But if the anticipation of the managing team is wrong (for example the general level of interest rates rise instead of dropping) the results may be worse. You have just in this case to undertake a new swap to invert your position, but you may loose some basis points.Swaptions may be also at stake, and many others specific derivative instruments that you will find on the OTC market with a counterparty risk.

  • Tadesse Fikre Teferra asked a question in Postharvest:
    Any body with any suggestions on low cost and simple (non-sophisticated) techniques for preserving tropical fruits?

    The postharvest losses of fruits in the tropics is very high and there are continuous efforts being exerted to overcome this challenge. I just wanted to here some research findings and/or success stories of simple and affordable technologies applied in other areas.