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  • Sivasubramanian Ramani added an answer in H9C2:
    I'm trying to revive H9C2 cardiomyocytes. Its been almost 18 hrs there is no adherence yet, kindly suggest me what should be done?

    Since my cells got contaminated I'm trying to revive my preserved H9C2 cells. What I did is thawed the cells at 37 degree C and washed with 7 mL of DMEM, further i washed with PBS for another 5 and then I added supplemented DMEM and incubated it. 

    When I observed it next morning I'm not able find any cells adherence and change in the colour of media to pinkish. Does cells take long time for adherence when its revived from preservation state?

    what could be the probable reason for this and what should I do now to revive the cells.

    Sivasubramanian Ramani · SASTRA University

     @ Richard Tan Yi Jer

    Thank you for the valuable suggestion. I will try to revive those cells again in the mentioned way. 

  • Claire Summerson asked a question in Purchasing:
    Does anyone know where chemchrome v6 (CV6) can be purchased?

    (formally sold by Chemunex)

  • Çılga İşcan added an answer in Molecular Biological Techniques:
    How can I deal with lysis buffer at cold temperatures when the sodium precipitates?

    I brought a solution of queen's lysis buffer with me to the field in Peru recently. It appears that the salts have precipitated (there is a layer of white solids on the bottom of the jar). This occurred after reaching high elevation where temps are around 10C at night. I have been told that the cold can cause the precip, but i would like to know more about (1) how to immediately rectify the problem and (2) how to deal with the situation in the long term given that I will be working at these temps all the time. The solution is for preserving blood samples. Thank you.

    Çılga İşcan · Izmir Institute of Technology

    I think you should make it re-soluble in water bath about 60 Celcius degree.

    or you should add glycerol or something like it.

  • Anna M Ohman added an answer in Plagiocephaly:
    What are your experiences in measuring plagiocephaly and brachycepahly with a craniometer?

    I use a craniometer daily to measure infants with plagiocephaly and/or brachycephaly. It is not easy as infants do not always cooperate, but I think it work well after some training (if using a headband with marks). This weekend I had inexperienced therapists (inexperienced in measuring with craniometer) measuring models of infant head ("home made"), it ought to be rather "easy" as this model heads do not move. However the result was not as good as expected, (I will do it again with better models of heads).

    I would like to know about others experience with measuring with craniometer.

    Anna M Ohman · University of Gothenburg

    Thanks Mauro and Alvah

    I was probably not clear enough when asking the question,

    I new about several methods but were more interested in others clinical experience of measuring. Flexicurve CPM etc for all the infant has to be in right position and not move.

  • Pepijn de Vries added an answer in Netherlands:
    Map of administrative boundaries of the Netherlands including Tweede Maasvlakte?

    A map (preferably shapefile), free of charge, of the administrative boundaries of the Netherlands which includes the reclaimed land of the Tweede Maasvlakte is what I'm looking for. www.gadm.org offers the kind of maps that I need. However, these maps do not include the Tweede Maasvlakte. Any help to point me in the right direction is welcome.

    Pepijn de Vries · Wageningen University

    Thanks for the useful tips!

    @Sharon: pdok provides many useful maps. The administrative boundaries provided there, do not really contain coastlines. Perhaps I should have stated that in my question, as my main focus is on the coastline. Also, the file doesn't seem to contain a coordinate reference (although my guess it's in Rijksdriehoek projection).

    @Hein: thanks for pointing me to the website of the Province. There are several maps there, but could not directly find what I was looking for. Maybe I will ask around further at the Province.

    This is what I used as a preliminary solution. I've extracted the polygon tagged "Maasvlakte 2" from www.openstreetmap.org. and merged it with the boundaries provided by www.gadm.org. As the shapes do not fit seamlessly, I had to do some manual tweaking. Not ideal, but it gave me something workable to produce simple maps with a coastline.

    For those interested, I've attached the Maasvlakte 2 shape as an R-object, plus the R-code I've used to merge this shape with the boundaries provided by gadm.org...

  • Noor-ul-Huda Ghori added an answer in FigTree:
    How do I put time scale for estimating divergence times without fossil calibration, with molecular data using BEAST and Figtree softwares?

    Hi, I try to use BEAST software for estimating divergence times for some of fungal species/populations. I use sequence data of five coding regions and do not use any fossil calibaration. One of the biggest trouble for me, I can not put or see or interpret time scale when I illustrate output of BEAST on Figtree. Does anybody have any idea or suggestion? Or any other user friendly software suggestion for that? Thanks....

    Noor-ul-Huda Ghori · National University of Science and Technology

    The fig tree has an option SCALE AXIS. tick that and you will get your time scale. 

  • Marek Adamus added an answer in Western Blot:
    What is wrong with my western blot?

    Anyone with good Western Blot trouble shooting skills? I am repeating a western that has ALREADY BEEN DONE successfully. And I have done it twice now and there is ZERO Protein on my blot. I can see the visible bands from the ladder, but thats not developing either. I tried a different developer, nothing. I used ponceau today and there is no protein on the blot.

    I use the TGX Turbo transfer system so the program is set exactly the same every time so I didn't over transfer or under transfer.

    I am processing the lysates exactly the same...

    Does anyone have ANY advice?

    Marek Adamus · Central European Institute of Technology-Czech Republic

    It is also possible to stain your gel with Coomassie Blue (colloidal solution eg. from Biorad, I have never tried a normal one) and then you can use the same gel for WB. The stain will transfer as well so you'll se whether you have a problem with the transfer or not. The membrane can still be used for a detection afterwards.

    I used Biosafe Coomassie Stain (Biorad) and a nitrocellulose membrane. Not sure if it works with PVDF.

  • Huma Qureshi added an answer in Importance Value Index:
    Which biodiversity index is more reliable/better and how can it be applied to a mixed vegetation? How might I differentiate diversity indices and IVI?

    Which biodiversity index is more suitable; Shannon’s index or Simpson’s index to apply on a mixed vegetation of more than 2 sites?

    Can we apply two indices together or one index is enough to get dominance, richness, evenness, and diversity of plant species from a mixed vegetation (tree, shrub, and herb) of 7 sites in a study area?

    What is the Importance value index (IVI)? Is it also applied on the same data on which we have applied Shannon's or Simpson's index? 

    How to interpret all these indices? 

    Huma Qureshi · PMAS - Arid Agriculture University

    Dear Dr. V. K. Srivastava

    May I get pdf of book "Fundamentals of Ecology by E. P. Odum"?

    Thanks in anticipation


  • Andrew Mercer added an answer in GDAL:
    GDAL Java binding Vs GDAL Python Binding. Which one is better?

    My purpose is to process optical as well as sar for standard operations like projection,   decomposition etc and mainly implement few of my algorithms.

    I have some preliminary knowledge of Java and am totally new for Python. Some site suggest that Python has better references and Java is hard to implement in many cases. Some suggest using Java binding. I am a bit confused.

    Which binding do you prefer for me?

    I am a windows user.

    Andrew Mercer · Stockholm University

    I have almost no experience of Java so my opinion is based only on my knowledge of Python and GDAL but I would say that Python is the way to go. Python will also give you access to Numpy libraries for non-geospatial analysis. There is a great deal of support for Python and it is a language that is used for scripting in many systems such as ArcGIS and QGIS. 

    Python is also installed as standard on Windows, Linux and OSX but you may do well to check out "Anaconda". This is a handy installer etc. that gives you a standalone Python installation with lots of scientific libraries included. It even has the bindings to GDAL. 

  • Mustafa Tuncer asked a question in Spark Plasma Sintering:
    Does anyone know about differences between spark plasma sinterind and flash spark plasma sintering?

    does anyone know about differences between spark plasma sinterind and flash spark plasma sintering

  • Thomas Wohlgemuth added an answer in Archaeobotany:
    Can anyone suggest me some seminal pubclication about the vegetation history of the alps since last glacial maximum?

    We are working on biogeography of the vegetation of italian alps. Thank you!!!

    Thomas Wohlgemuth · Swiss Federal Institute for Forest, Snow and Landscape Research WSL

    Hi Pierangela:

    check the papers of Willy Tinner, e.g. Wick & Tinner (1997) in Arct Alp Res. The paper may reference additional literature.

    Best wishes


  • Georges Landa added an answer in Raman Microscopy:
    What information can be extracted from the intensity, FWHM and raman shift of the ZnO Raman spectra ?

    Raman spectroscopy is powerful tool ti investigate the phase and purity of the crystal. But How ?

    What are significant of the intensity, shifting and FWHM and how? 

    Georges Landa · Laboratoire d’Analyse et d’Architecture des Systèmes (LAAS)

    As explain by Dr Hatsuo Ishida, all spectra parameters are sensitive to the local or long range order of atoms in the compound. It is always a good practice to make relative measurements of these parameters, for example by comparison with a test-sample.

    Some years ago we could rely some intensities changes to the presence of twins In other cases we explained the frequency shift changes du to strain effects in heterostructures and last the variation of FWHM to the change in the lifetime of the excitations involved in the processes.

  • Sohan Jheeta added an answer in UV Radiation:
    How can I calculate the UV dose, in J/m2?


    I used three UV lamps each at a time:

    UV A light source (365nm, 8 watts) Aimed at a surface 5 cm away for 7 Days

    UV B light source (302nm, 8 watts)Aimed at a surface 5 cm away for 7 Days

    UV C light source (254nm, 8 watts)Aimed at a surface 5 cm away for 7 Days

    Can anyone please help in explaining how to calculate the UV dose in J/m2 for each of the above on the mentioned surface during the full week exposure? 

    Is this correct?

    (Peak density W/M)X (time )= J/M2 ?

    Thank you

    Sohan Jheeta · The Open University (UK)

    Tariq, there is information missing - what is the size of your beam spot?

    I'll answer later in the week as I'm at a conference.


  • Abdul Rauf Shakoori added an answer in BSL-4:
    Does anyone know about BSL-3 labs in Africa?

    There are two BSL-4 labs in Africa. What is total number of BSL-3 labs in Africa? if somebody know, please also share the link of source of data. Thanks

    Abdul Rauf Shakoori · University of the Punjab


  • Vipin Nair added an answer in Heat Exchangers:
    How do I carry out chemical cleaning of shell and tube heat exchanger?

    Nowadays, I have been trouble to control test condition of fin-tube heat exchanger. I think that this is based on cleaninig problem of shell and tube heat exchanger placed on auxiliary system and disassembling is very difficult, so that I have to clean it as chemical but I don't know which chemical material should be used and whether chemical may be detrimental effects on copper pipes.

    Vipin Nair · Sardar Vallabhbhai National Institute of Technology

    If you want to use chemical cleaning method then it would be better if you ask the manufacturers regarding the chemicals.

    Normally,for steel and copper tubes phosphoric and sulphamic acid is preferred and one should never use  hydrochloric acid and sulphuric acid .

  • Kiyoung Yoon asked a question in Library:
    Could I target more high molecular weight DNA size for PacBio?

    why can't i use intact genomic DNA for PacBio system? When i extracted gDNA from bacterial cells, most of DNA size are more than 10-20kb. but most of papers and protocols have used targeted gDNA size like 6kb. if it is impossible to make high molecular gDNA library, how can make less fragmented gDNA library for PacBio(more larger than 10kb SMRTBell library)? 

  • Nadezhda Serebryanaya added an answer in Miller Index:
    Is there any program to determine hkl from 2 theta ?

    Is there any program to determine hkl from 2theta?

    Nadezhda Serebryanaya · Moscow Institute of Physics and Technology

    If you have 2 theta of your diffraction peaks, you may use DICVOLV  or TREOR programs. Then you get symmetry and  cell parameters of your materials. Using intensities of your diffraction peaks you may solve atomic positions, but it is not simple as a determing of hkl from 2 theta.

  • Arthur Wing Hang Li added an answer in Protein Purification:
    Can anyone suggest an E. coli expression vector with the GST in the C-terminal of the insert?

    It is for protein purification, and I would like it to be IPTG inducible.


    Arthur Wing Hang Li · University of Sussex

    Just a small piece of advice. I usually do ligation independent cloning and PCR the gene out with an overhang that matches the vector, so I don't have to worry about the compatibility of restriction sites. Though I understand that many researchers prefer the more traditional method of cutting and pasting.

  • Amin Hadidi added an answer in Ferrofluids:
    Why are ferrofluids not electrically conductive?

    Why ferrofluids are not electrically conductive fluids? Why they are dielectric fluids?

    Ferrofluids are colloidal liquids made of Nano-scale ferromagnetic, or ferrimagnetic, particles (such as iron and copper) suspended in a carrier fluid. As the metals are electrically conductive materials, dispersion of these particles in the water should result in high electrical conductivity of the magnetic fluid; but why these fluids are considered as dielectric fluids?

    Amin Hadidi · Islamic Azad University of Ahar

    I have read some papers concerned with effects of uniform magnetic fields on magnetic fluids. As we know, a uniform magnetic field only affects the electrically conducting fluids such as the force acting on a wires carrying electricity in a magnetic field. Also as you said, the magnetic fluids are dielectric. So, how the uniform magnetic field affects dielectric magnetic fluids?

  • Bolok yazdi Hamid reza added an answer in Basic Molecular Biology Techniques:
    Can you give me a protocol for simultaneous ligation and digestion of the PCR product?

    can i digest and ligate the PCR product to vector by ECORI and BSP119I?

    I using fast digest Thermo Scientific enzymes.

    Bolok yazdi Hamid reza · Zabol University

    hi dear mohammad

    pls read these articles

    good luck

  • Anuj Singh asked a question in Nude Mice:
    Will reinjection of a tumor cell in the same set of mice produce a tumor or not ?

    Previously I have injected U87 in female Nude mice 5 million /mouse with matrigel. Tumor came in all injected animals but only few tumor started to grow and most of the other tumor started to regress even though in some animals tumor completely disapeared.

    I want to inject some other cell line in those animals whose tumor completely disappeared.

    Will it work and tumor will grow or not ?

    If anyone have experience in these type of question please clear me

    I will be highly obliged if anyone will help me

  • Andrew Mercer added an answer in Kriging:
    What is a good self study source for robust and reliability-based design optimization using kriging method ?

    Thanks in advance!

    Andrew Mercer · Stockholm University

    A good introduction to geostatistics and kriging is "Geostatistics for Environmental Scientists" by Richard Webster and Margret A. Oliver, 2007, Wiley. 

    They lead you through the steps of analysis and provide good guides for design. This book really is aimed at educating for use rather than laying out mathematical foundations, but this does not make it  kriging "lite". It does require a reasonably good grasp of statistics.

  • Hélène Peyret asked a question in Fura-2:
    Hello, Have you technical procedures to quantify intracellular calcium with real time kinetics using Fura-2 in beating adherents cardiomyocytes ?

    (reading by fluorescence microscopy)

    Thanks !!! 

  • Wolfgang F. Schwarz added an answer in Diaspora:
    Has anyone any advice for literature review on the accordion family effect/boomerang kids on returning emigrants?

    I am presently doing a thesis for a masters in Contemporary studies in Migration and the Diaspora and I wish to study the effect of returning emigrants to Ireland in the present economic climate, specifically those who return and have no choice but to live in with their families and thus the challenges both the family and returning emigrant experiences.  Any information/advice would be greatly appreciated.

    Wolfgang F. Schwarz · University of Leipzig

    ... an not to forget in the wider (postcolonial) context of India: Rushdie's " Booker Price winner-book "Midnight's Children" (1981) which was filmed. You find a fine description  on


    Regards again


  • Lorenza Ferro added an answer in Pigment Extraction:
    How can I calculate pigment concentrations in green algae?

    I want to calculate spectrophotometrically the concentration of Chl a and b after extraction with acetone 90%.

    Can I use the equation from Jeffrey and Humphrey (1975), even if green algae do not have chlorophyll c?

    Moreover, does anyone know the same equations if I use ethanol as solvent for pigment extraction?

    Lorenza Ferro · Umeå University

    I used acetone 100% and EtOH 95% and they both worked well, but I had first to disrupt cell walls through a homogenization step. The results were comparable and the pellet was quite white after 1 or 2 steps extractions.

  • Dilip Kumar Pal added an answer in Potassium:
    Is it correct to determine potassium content from sap of the plant?

    Generally potassium in the plant will be determined after digestion with tri acid or di acid or single acid method. Based on the review of literature i came to know that the potassium content of the leaf can also be analysed by directly feeding the sap of the plant in flame photometer. Is it correct method to determine the K content of the plant by directly feeding the sap of the plant in flame photometer? if it is correct how much accuracy will be there and how it can be compared with other methods?

    Dilip Kumar Pal · National Bureau of Soil Survey and Land Use Planning

    The  scientific reason for proposing such method  if available may be discussed.

  • Lynne A Kelly asked a question in Flow Cytometry:
    Does anyone know if there is a specific marker to identify neutrophils using flow cytometry?

    I am working with whole blood samples with a specific interest in neutrophils.

  • Larissa Luvison Gomes da Silva added an answer in Cadaver:
    Can I get advice on preparing tissue slides from cadavers?


    I need to prepare tissue slides from cadaver tissue. Does it need to be fixed, dehydrated, and embedded in paraffin like fresh tissue?

    Also, what would be an appropriate medium for storing cadaver tissue? PBS, physiological saline, water, or perhaps cadaver fluid?

    Thank you!

    Larissa Luvison Gomes da Silva · Citopar - Centro de Citologia e Patologia Paraná

    The best way to preserve the tissue is in formalin and then prepared in paraffin.

  • Bishnu Marasini added an answer in Agar:
    What is the purpose of using diluted gar plates for CFU number enumeration?

    Recently reading a paper I found out that some people use 1/5 diluted agar media for colony forming units (CFU) enumeration. Does anybody know the reason for that? Or it is just the way of saving expansive media?  

    Bishnu Marasini · Tribhuvan University

    Diluted agar media does not interfere the motility of bacteria.