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  • Who are the commercial producers of Ra-226?

    The reason is that Ra-226 its used in the production of Ra-223, that in turns is used as radiopharmaceutical for, at the moment, prostate cancer (breast cancer treatment under clinical trials).

    Dear Mr. Russak,

    thank you for answer.

    Kind regards.

  • Mattia Veronese asked a question in Atlases:
    What is a good threshold for the mRNA expression for the Allen Brain Atlas?

    Hello everyone, I've been working on the aggregation of mRNA samples within the Allen Brain Atlas (http://human.brain-map.org). I realised that when the samples are averaged in a brain region (for those of you that now the atlas, I'm referring to the coarse resolution), the mRNA expressions of the samples is threshold? I wrote to Allen Institute to know the exact procedure to do it, but they haven't replied yet.

    Does any of you know how they process the data from sample to coarse level?

    Does any of you know a rational threshold to delete of the samples with minimum expression?

    Thanks in advance


  • How can I fix unknown lines in SDS-PAGE electrophoresis?


    I take a SDS-PAGE electrophoresis gel. It appears some lines which I don't know what they are. The line connect all wells of gel and they are more than two.

    What's it and How to fix my trouble?
    Please help me.

    Rosa María Martínez-Espinosa · University of Alicante. Faculty of Sciences

    Is it silver stained? It seems you have exactly the sample in all lines. The only difference taking into account the number and position of the bands is the concentration. Some suggestions to be considered:

    - Clean crystals with ethanol before to prepare the gel.

    - Prepare new buffers.

    - Use gloves to prepare the gels

  • Stefan Domonkos asked a question in Income Tax:
    Does anybody know of an internationally accepted measure of personal income tax progressivity?

    What I have in mind is a numeric (preferably continuous) measure of personal income tax progressivity that allows to compare countries in a consistent manner.

  • Patrice Simard added an answer in Fourier Analysis:
    How to remove cyclicity or diurnal behavior from a time-series dataset?

    Hi all, 

    I have a long time-series data with a clear diurnal behavior (cyclicity). Any ideas, publications or works on how to do it? I'm thinking of a Fourier Analysis, but I wonder if anyone has dealt with this problem before?


    Patrice Simard · Université de Technologie de Compiègne

    Basically I would agree with Paul and Juehui. However, it depends a lot on why you want to remove the diurnal part. One can suspect that it will be mainly low frequencies for instance, so that maybe you can applied a multiscale analysis. Then you can expect to see the details you are looking for in the highest details signals.

  • Is half knowledge too dangerous?

    Half knowledge becomes dangerous, when you actually assume that you know enough to take a decision. Half knowledge in medicine, drugs, chemistry, business, engineering, and in other disciplines is too dangerous.

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    You can have any fractional part of knowledge or ignorance. I don´t know any person with full knowlwdge. This would be a miracle!

  • Peter Jürgens added an answer in Damage Mechanics:
    Why does the damage threshold of material decrease as the laser wavelength increases?

    The usual model of optical damage of material by laser involves an electron avalanche process.

    If the damage mechanism is dominated by "electron avalanche",the damage threshold of material will decrease as the laser wavelength increase.


    Peter Jürgens · Leibniz Universität Hannover

    From a more theoretical point of view the avalanche ionization rate is proportional to the absorption cross section. This cross again depends quadratically on the wavelength (see for instance: http://www.opticsinfobase.org/view_article.cfm?gotourl=http%3A%2F%2Fwww%2Eopticsinfobase%2Eorg%2FDirectPDFAccess%2F9D5A3AAE-D018-466D-A8129BA1C7B978FD_183465%2Foe-17-15-12269%2Epdf%3Fda%3D1%26id%3D183465%26seq%3D0%26mobile%3Dno&org=)

    This leads to a significantly increasing ionization rate for increasing wavelength and results in a decreasing damage threshold.

    The theoretical results shown in fig. 5 also show a decrease of LIDT as the wavelength increases within one multi photon order.

  • Zaw Ko Latt added an answer in Chlamydomonas:
    How can I transform C.reinhardtii CC124 by glass bead?

    Hi, everybody!

    Now I am trying to transform wild type C.reinhardtii CC124 with 1302 vector by glass bead. I am not so familiar with Chlamydomonas strains. In research papers, it was reported that mating type (+) and (-) was mixed before transformation and they obtained mating type (+) and (-) from from stock center . I have only wild type C.reinahrdtii CC124. To transform by glass bead, how should I continue with this wild type strain? I am strongly expecting everybody's suggestion and will treasure any advice.

    Zaw Ko Latt · Mandalay Technological University

    Dear James Gregory,

    Thank you so much for your answer and suggestion. For me, I have got invaluable knowledge to continue my research. 

  • Olivier Zelphati added an answer in Gene Therapy:
    Anyone knows how to concentrate condition medium from AAV triple transfected 293 cells growth media?

    Currently I am working on AAV triple transfection. According to the paper Lock,etal, human gene therapy, 2010. AAV virus can release from cells into media. We do not have TFF as what they used in their core lab. Any other replacement method? Thanks a lot!

    Here is the paper:http://www.ncbi.nlm.nih.gov/pubmed/20497038

    Olivier Zelphati · OZ Biosciences

    If you want to concentrate your virus from culture media you can use mangetic nanoparticles such as Mag4C Kits. This is a very easy and rapid magnetic concentration method. You can get information in the link or here directly http://www.ozbiosciences.com/magnetic-virus-concentration/47-mag4c-ad-magnetic-adenovirus-capture.html

     Best Wishes

  • Walter Demmelhuber added an answer in Spanish:
    Why can companies limited points of sale according to border lines within the EU?

    Digital content can be purchased nowadays principally in three ways:

    • downloadable files (being e.g. mp3 or executable programs)
    • data carriers like DVD, Blueray, etc. shipped by mail
    • online streaming usually for visual content

    Looking at the post-purchase situation

    • there are no legal constraints to move legally correctly purchased data carriers or downloadable files with you from one country to the next
    • if you sign up for an online streaming service in one country and want to see it e.g. during a trip in another country it is quite typical that the service is not available

    Looking at the pre-purchase situation

    • for downloadable files and streaming, a cross-border purchase usually does not work (I tried e.g. with Amazon Spain to purchase a certain mp3 (spanish film musik) while being in Spain and it did not work with my German account - although other stuff I could purchase - I had to open a Spanish account. From Germany obviously it did not work at all)
    • DVDs and Bluerays (except for English and in my case German) in foreign languages are usually not available locally for purchase. Rarely you find a DVD with Spanish language track here

    The European Commission for the Interior Market and Services is presently investigating this and asking for public and company opinion because it is contrary to the free mobility of services in the EU. The licensing regulations at national level are clearly intended to limit access and make the data content more profitable.

    I personally believe that it also constitutes discrimination because it withholds easy access to multi-language diversity - something the European Commission acknowledges as well.

    I certainly know the case of C-403/08 Karen Murphy but does anybody also hold other legal knowledge or theories?

    Walter Demmelhuber · Friedrich-Alexander Universität Erlangen-Nürnberg

    Hello Carsten,

    the best example where the EU meddles with private enterprises is in reducing and actually starting in 2016 killing roaming cost for mobile phones.

    Another example would be that grey imports of cars are completely legalized and what a mess the car manufacturers made out of this in the beginning.

    So why should this not apply to digital content?

    Regards, Walter

  • Sergio Nogales added an answer in UV Radiation:
    Is UV light useful for sterilization? Is it effective on human?

    What is the ideal time for sterilization by UV light and are humans affected by exposure to the UV light?

    Sergio Nogales · Universidad de Extremadura

    Hi Hamzah, I am going to answer your question from a "food processing" point of view:

    UV is usually effective for sterilization, but you need to consider that its use is affected for some factors, especially concerning:

    - When the object produces "shades" on its own surface, where UV can not reach, its global effect is lower.

    - If you are working with water, and its turbidity is considerable, UV's is not much effective, and you should use complementary treatments.

    - Its application time depends on many factors. In general, to affect DNA of microorganisms in water, it takes at least 20-30 minutes, depending on the lamp capacity, turbidity, water flow, etc.

    - UV applied directly in humans is not advisable, generally.

    In short:

    - Make sure that the whole surface is (regularly or constantly) irradiated by UV, consider the different factors affecting this UV irradiation (is it by air, water?), and avoid exposure for humans.


  • Are there any valid and reliable measures for one's tendencies to be sexually compliant or coercive?

    I am studying the possible connections between attachment styles and individuals' tendencies toward coercing a sexual encounter and complying to a wanted request for a sexual encounter. Are there measures, with good validity and reliability, for sexual compliance and coercion? 

    Alexander Crooke · University of Melbourne

    Something that might be of interest is that experience sampling methods (ESM) have been used to investigate the relationship between affect, social context, and sexual intercourse in adolescents. Using ESM has been found useful for addressing recall bias, facilitating openness in responses to sensitive topics, and a range of other benefits.


    Shrier LA, Koren S, Aneja P, de Moor C. Affect regulation, social context, and sexual intercourse in adolescents. Arch Sex Behav 2010;39:695–705.

  • Martha Suh added an answer in Critical Thinking:
    What methods have you found to be effective for helping students improve critical thinking skills?
    In my experience, most undergraduate students tend to be naive and accept information without much critical analysis. I have been experimenting with methods for teaching the basic skills of critical thinking, and I would like to read about other educators' experiences in this area.
    Martha Suh · Hôpital Maisonneuve-Rosemont

    There have been quite often " What kind of research projects are you going to propose to support your findings ?? during examination for Ph D candidates. It was very useful for  future Researchers.

    Martha 서 

  • How far can (and does) tourism contribute to poverty reduction?

    There is usually a general acceptance that tourism contributes to poverty reduction, at least in theory. The realities tend to be different and hence am interested in hearing about people empirical and anecdotal account of tourism's role in poverty reduction and the factors that shape this role (especially in developing countries).

    Mohammad Sajjad Abro · Management and Development Center

    Tourism can contribute in economic growth, but not necessarily reduce poverty. In poor countries, revenue generated through tourism goes into state coffers (much of amount is lost in corruption) and is rarely spent on development of local communities. Tourism, on the contrary, badly affects local culture and environment. In rich countries, with only relative poverty, states make adequate policies to promote tourism, ensure safety of tourists, ensure protection of local environment. But in poor countries, that lack proper policies and enforcement of law, tourism hardly brings any positive change in the lives of local communities. 

  • Zbigniew Kowalski added an answer in ERDAS Imagine:
    How do I save this file from Landsat8?

    Atmospheric correction of Landsat8.

    I use ENVI 5 for atmospheric correction of LANDSAT 8 data, but unable to open the resulting output file in ERDAS imagine.

    Zbigniew Kowalski · Państwowy Instytut Geologiczny

    In ENVI you have direct option - save file as ERDAS IMAGINE

  • Michel Vorenhout added an answer in In Situ:
    Any suggestion for easy identification of metals in water and soil?

    Have you any suggestion for easy identification of metals in water and soil? 

    For cheap intrumentation

    In situ?  and in laboratory?

    Michel Vorenhout · University of Amsterdam

    You want cheap, or good? What metals?

    XRF is not really a cheap machine, and if you don't have a lab you will need to pay for the analysis. Some producers claim to have water sensors for various ions, if you don't need precise data that might be worth a look.

  • Enrique Vidal Sanchez added an answer in Octave:
    Is there any application which is compatible with Matlab?

    I have to do experiments with Matlab code and try to run in other application. I already tried Octave and it need some modifications. Any other application which I can use to run Matlab code?

    Enrique Vidal Sanchez · Wavestar A/S

    You can also embed Matlab code into Labview but if you are looking for a free (or open source) alternative to Matlab software, the above suggestions are a good starting point. But the most compatible software with Matlab code is Matlab ;-)

  • Piotr Jaskula added an answer in Cement:
    Can anybody suggest methods or tools to increase early strength of cement?

    Intoday world speed of cxonstruction really plays vital role so can any body suggest some methods or tools to increase early strength of Cement and concrete especially one day strength.

    Piotr Jaskula · Gdansk University of Technology

    use high strength cement or additives which accelerate bond.

  • Michael Kurz added an answer in Moths:
    Lepidoptera storage: What can I do with thousands of unidentified moths in ethanol?

    I am working with a collection of > 3000 light trap samples collected in Grand Canyon, AZ, USA over the last three years, with up to 1500 more samples coming in each year. They are currently stored in 250 mL plastic Nalgene containers, and are identified mostly to order with the exception of aquatic taxa.

    The time has come to consolidate this bulky sample set. I know it is always better to save specimen, but what about moths in ethanol? Will a specialist ever be willing to look at these? My lab does not have the time to pin these, and they do not pin well after sitting in 95% Etoh for 2+ years anyway. Can anyone honestly advise throwing these specimen away without a sinking feeling in their belly?

    Michael Kurz · Naturkundliche Gesellschaft

    DNA-Analysis (see http://www.boldsystems.org/) is presently the most easiest way of identifying alkohol-preserved specimens and it may also become cheaper in the furure. For that reason, you should store the specimens in absolute ethanol as soon as possible after catching them and not do any other treatment. Do not add formalin or any other chemical and do not use methylated spirit. Such samples can normally be identified well, provided that they are not older than about 10 years.

  • Gyorgy Banhegyi added an answer in New materials:
    How to choose laser wavelength of raman spectrascopy for new material ?

    From various wavelength = 488 or 514 or 785 nm. In metal doped Semiconductor shows some small difference only between 488 and 514nm. Please tell me to fix laser.

    Gyorgy Banhegyi · Medicontur Ltd.

    The basic rule is that a wavelength is selected which produces the least luminescence.

  • Ian Baillie added an answer in Reservoirs:
    Could anybody tell me the correlation between SOC, C:N:P ratio with GHG emission, to predict GHG emissions in the catchment of reservoir?

    correlation will give some idea about GHG emissions w.r.t C:N:P , SOC

    Ian Baillie · Cranfield University

    If you are intetsted in GHG emissions from the whole catchment, potential methane emissions from the reservoir itself can be a significant contibutor even though it covers only a small fraction of the area.

  • Sravan Muguda added an answer in Soil Improvement:
    What is the advantage of water in soil engineering properties?

    As far as I know and understand that water in some cases will give bad effect to the soil engineering properties. It is known from the fact that in most of soil improvement techniques, problem caused water should be handled, such as water pressure. Is there any advantage of water in term of soil engineering properties, especially that related to soil improvement.

    Thanks. :)

    Sravan Muguda · BMS College of Engineering

    Water is also useful in application of certain non- traditional stabilizer like enzymes for soil stabilization. These stabilizers are mixed with water prior to its application to the soil or sub-grade soil. 

    Water also plays an important role in preparation of bentonite slurry in ground investigation. The slurry stabilizes the walls of the borehole in case of loose soils and thus helping in retrieval of soil samples during soil investigation.

  • Mattia Veronese added an answer in PET:
    Could any one suggest a good reference book for PET? concentrating more on Neuro imaging?

    I just want to work on the imaging modalities of PET in Alzheimers Disease..

    Mattia Veronese · King's College London

    Hi Dr. Nivins,

    if the purpose of the book is a quick introduction to PET and how to use it (from design experiment to data analysis) I would recommend this book:


    It is not too theorical as most of the book, rather it contains practical suggestions about how using it.

    I hope it helps



  • How easy is it to develop a positive communication between the oil and gas and the educational industries?

    After attending and presenting in the last GetEnergy Abu Dhabi meeting, how easy is it to develop a productive communication between the oil and gas and the educational industries. This help to identify the gap and find ways to close it considering the expectations of the oil and gas industry. 

    Dr. Khalid Salim Al-Jardani · Ministry of Education, Sultanate of Oman


    This can be done a bit earlier which would be with the selection of their college level studies. However, the question is do different industries give any kind of support for the educationalist and education?!

  • Shahid Chaudhary added an answer in Gene Editing:
    gRNA cloning strategy?

    I am naive to this CRISPR/Cas9 system for gene editing. As a part of my research project, I want to establish this protocol in my lab to knockout the E6 and E7 oncogene of HPV16 and HPV18 virus. I have designed the gRNA using the ZiFit software and now I have to clone the gRNA fragments. Can anyone suggest me a good and easy protocol for cloning gRNA fragments? Also the software has suggested nearly 7 gRNA, do I have to clone them all and screen one by one to check the efficiency of gene knockout? 

    Shahid Chaudhary · University of Zurich

    Thank you very much. Will give a try to this protocol.

  • R. M. Mehra added an answer in Graphene:
    How can I make a good single layer graphene film?

    I made some graphene films using CVD technique. But Raman analysis showing no 2D. How can I make a good single layer graphene film and what are those precautions I have to maintain?

    R. M. Mehra · Sharda University

    Try this. See attachment.

  • Bounded Rationality: Herbert Simon's concept
    We have cognitive limitations which limits our capacity to process all the information all at the same time. How is such Capacity Bounded, and why is it so?
    Yoshinori Shiozawa · Osaka City University

    Gavin Rits,

    we are using the term "information processing" in a figurative way. Few people believe that we are thinking in the same way as machines or computers respond  to  outer world.

    However, we can observe certain parallelism between computer and human responses. For example, at a most abstract layer, both responses can be formulated as a chain of reactions of the form  qSS'q'. Here q stands for an internal state, S the state of the outer (sometimes inner) world, the target of observation being determined by the internal state  q. If the state is S, then the computers or humans do S to the outer world and transit to state q'. If the state observed is not S, the internal state returns to the "next" state q. 

    In the computer case, outer world is a tape or a memory and inner state is the state of CPU or a line of the program we are examining. S means reading the letter at the head, and S' means writing a letter to predetermined place by q'.  In the human  case, inner world is brain and  outer world is the world including our body.

    It is well known that any computer program is constructed by a set of ordered set of qSS'q'. Indeed a computable funciton is defined as a finite set of these quadruples.

    If you observe human behavior, you will find that our behavior can be decomposed of if-then reactions of the type qSS'q'.  See for a detail §6.3 Rule-based behaviors of my paper Evolutionary Economics in the 21st Century a Manifest.

    As the above example shows, comparison of human or animal behaviors and computer programs are useful, provided  that we are reasoning in this abstract level.

    This abstraction is a powerful and precious tool  for us to understand a complex phenomena as human and animal behaviors.  

  • Sai Gm added an answer in Simulink:
    How can I calculate the simulation time using embedded matlab function in simulink?

    I am using clock block as a input to the embedded matlab function so that I can calculate the simulation time but I need to give different inputs at different time intervals according to  simulation time. I need to get wave form same as in the pic.

    Sai Gm · Darmstadt University of Applied Sciences

    @ thanks Syed .....but i want to use m file for to find the time interval between two points.

  • Peng Qi Ling asked a question in Gaussian:
    From physical view, how can I comprehend the Gaussian and Lorentz fitting? under what situation, I should fit spectra using Lorentz?

    From physical view, how can I comprehend the Gaussian and Lorentz fitting? under what situation, I should fit spectra using Lorentz?

  • Gopalakrishna Palem added an answer in Computer:
    What is the relation between throughput and power in computers?

    I am trying to come up with a mathematical model for different parameters used in computers for performance calculation. Can anyone help me understand the relationship between throughput and power

    The problem is more deep and need concrete definitions.

    As a first step you might want to define 'performance calculation' in more concrete terms - as in 'performance of what', say, the 'algorithm', the 'process' or the 'cpu' or the whole 'system' itself.

    Then you can start defining 'throughput', as in 'throughput of process' or 'component' or 'cpu' or 'io' or the 'whole system'.

    Once you have these definitions - you should be able to workout the parameters and there by the equations.