CharonY

I hope these are not prefilled chambers? Those are rather nasty. Cervical dislocation is usually better, but one needs some skill to pull it off (no pun intended). Actually CO2 use is getting much disputed in a number of labs.

Recently I was forced to look into the US health system a bit. I get a premium fee for working at the university as such I only have to pay 50$ if I used an exclusive provider network or 150$ if I want to be able to make choices outside this network. I wonder how expensive health insurance for the average worker is, though. In Germany everyone is required to get an insurance. If you are an employee with a monthly income lower than 3.937,50 € you are automatically with one of the public health insurer, if it is equal or higher you may elect to join a private one. The lesser is more expensive but gives more benefits. Up until now I was in the public system and paid roughly the amount of what I'd pay for a PPO-choice. I do have to add that in Germany some of the stories from the UK (waiting for 3 weeks before one gets an appointment) is unheard of. From what I heard the standard quality and speed with which you get your treatments in Germany is comparable with the USA, though you are treated preferentially if you are privately insured (in Germany). So basing on this it appears that (with the premiums) the US system is cheaper if I only use physician within the network. How well that works out depends of course how large the network is. Other than that there are additional costs: Physician visits: 10$ per visit, 20$ for specialists in the USA; 20€ per 3 months (regardless how many and which physician/specialists you visit) in Germany. So if you have to often consult specialists in Germany you are better off. It is even worse if you have to consult an out of network specialist. Here you have to meed 300$ deductibles and pay 30% of all costs on your own. In Germany it doesn't cost extra if you are referred to another specialist. Preventive care: 10$ (or 30% out of network) in the US; free in Germany These are some points that I'd have to pay out of my pocket and can be easily quantified and does not tell what actually is covered. However it appears that the German insurers appear to cover a bit more. For instance they also pay for treatment of mental illnesses and dental work, whereas in the USA you need yet another insurance.

Ah I see. Thanks for the info!

That is somewhat unlikely. This bacterium would be over 200 microns and thus even longer than eukaryotic cells. From this pic I wouldn't even be sure whether it is organic.

I'd say yes. However it would help if you could indicate the size of the scale that you see in the pic (just stating a 125x magnification does not help per se as the image itself can be enlarged).

I am not following this candidate in any detail but I came across this article http://www.michiganmessenger.com/showDiary.do?diaryId=404 One point was that he is getting support from white supremacist organizations. Granted, this is not his fault per se. However in the article are some quotes, which I find questionable, though I have no idea whether they are authentic. Can anyone comment on this?

Right you are, my mistake. However, I can only reiterate, usually the hypotonic solution does not lyse the cells but merely swells them. You then add fixatives (e.g. acetic acid methanol solution) to maintain the cells in that state and makes the membrane instable. Then you just spread the cells on the slides. As I said, a precise description of your protocol would be helpful for any discussions. Alternatively check this article: Cytometry 2001, Vol 43, p101-109

Do you drop the sample from a slight height onto the slide? Most protocols for blood use hypotonic buffer to lyse the red blood cells. White blood cells are fixed and spread via dropping them onto a slide. If you lyse them beforehand I'd assume that the nucleus should maintain enough coherence to have the chromosomes lie together. In any case the idea is that by dilution and spreading the given nuclei become separated.

Ugh, studying evolution on this level in bacteria can often be a no-joy as HGE can be quite nasty to track. The majority of evolutionary papers in this field thus concentrate on the structure and selection constraints of given domains (e.g. Ravi P. Anantha et al. Infection and Immunity, December 2004, p. 7190-7201, Vol. 72, No. 12). Regarding the mechanisms of transmission, more is known. The operon of encoding the pilus are flanked by IS elements, indicating that this is a kind of genomic island (or islet), as you have already mentioned, moreover it is located on a plasmid, again a mobile genetic vehicle. A nice paper about the requirements on the mobility of this plasmid (pCoo) is this one: Barbara Froehlich et al., Journal of Bacteriology, May 2004, p. 3230-3237, Vol. 186, No. 10. and Journal of Bacteriology, September 2005, p. 6509-6516, Vol. 187, No. 18. While not precisely dealing with CS1 pili this review gives a nice overview about pathogenicity islands in general, something which in principal is also applicapble to the evolution of ETEC strans: Herbert Schmidt and Michael Hensel, Clinical Microbiology Reviews, January 2004, p. 14-56, Vol. 17, No. 1. I think to recall that I should also have some paper about the evolution of pathogenic E. coli strains somewhere, though I am pretty sure that again, the focus is on pathogenicity islands rather than on specific pili. But I'd have to dig a bit for them. I'll get back to you soonish.

Could you post your complete (and precise) protocol? It may be different from those that I know. Also, are you sure that you already lyse the cell in the hyptonic solution or do you just let them swell?

uhmmm... nope? The majority are colorimetric assays (Bradford Lowry etc.) but there are different other methods as well. The method you can use also depends whether you quantify a purified protein extract or a crude extract, for instance.

1) for quantity the dry weight or any other denominator of biomass would be easy to do. Quality is harder to assess. What makes one fruit of better quality to another (for the plant it is only of interest whether the seeds will spread efficiently, for those feeding off the plant taste or energy content might be more important). 2) If it is not in a controlled environment the easiest thing I can think of is a filtering by size e.g. nets of different sizes. 3) uhm... nectar?

The chromosomes between cells are not mixed during the process. Essentially the cells are fixed, spread (so that they don't overlap) and dried. The chromosomes are then effectively immobilized and the nuclei of the different cells are apart from each other.

Psst michael_mr, they are antiporters Also, if that was what confused you, the gradient is built at the expense of energy (ATP).

Nitrate is, under ambient conditions, not gaseous, of course. Hmm, most common gases produced during fermentation are indeed H2, methane and CO2. I don't know what else might be there in significant amounts.

Excellent point. Also I would think that there are quite some differences in the schooling systems between different countries, despite efforts to make them more comparable. Also the title of this thread is a bit misleading as the OP is rather a critique on the schooling system rather the academic system as whole (which quite possibly is even more flawed...)

He doesn't have to die. As Cap'n Refsmat pointed out, he just has to remove himself from the active gene pool. I wonder, though, what would happen if someone deposits semen or egg cells prior sterilization? Probably no award due to technicality.

You got 14 of the 21 people correct, and you did better recognizing the virginity of guys. Overall, you guessed better than 78% of all test takers. Bah if wanted to spot virgin guys I'd just have to go to the informatics class ;P

There are a number of reasons why primases are needed. The simplest one is that Primases (which are DNA-dependent RNA-polymerases) are able to directly synthesize onto RNA onto ssDNA, whereas DNA-dependent DNA polymerases, involved in the actual elongation, lack this ability. However, this synthesis step is somewhat error prone and by having another polymerase run over that bit again decreases the risk of replication errors. If the primases would add desoxyribonucleotides there would be no easy way to recognize these bits (which is otherwise done be RNase H in case of DNA-RNA hybrids).

MD, most likely.

I actively discourage my students to use wikipedia as a source, at least for citations. In my opinion correct citations requires the use of the primary sources. The basic principles that are well covered by wikipedia articles either do not need specific citations (one does not really need a citation if one refers to the dogma of molecular biology, for example), or require the identification of the underlying paper(s), anyway. Of course one can use the articles as an introduction to a topic, though I found the article especially in the areas that I work(ed) in woefully lacking. Of course I could go ahead and correct them (and in some instances I did correct gross errors), but then it simply takes too much time and effort.

Yeah you're right For some reasons I confused oxidation with reduction. Not only that I posted it wrong way round, too, to make my wrong point. Sorry about that

minor correction, you cannot further reduce CO2. In CO2 the carbon is already in the reduced form. The first step where of carbon fixation and where CO2 enters is a carboxylation of Ribulose-1,5-bisphosphate. In the Calvin cycle you need energy (ATP) and reduction equivalents (NADPH) that were yielded by the light reaction.

As each incubation step is long enough to ensure specific binding, cross-contamination is usually not an issue. There are different flavours of ELISAs but for instance in sandwich ELISA you usually use a high enough concentration of the first antibody to saturate the binding capacity of the respective wells. So even if you use different antibody on the same plate one would expect that small overflows would not add to the already saturated neighbouring plates. Later one you block the free antibodies using some kind of blocking reagent and so on. There may be specific variations where more care must be given, but the standard ELISA protocols usually ensure that cross contaminations as such do not occur (or are below the detection limit).

AFAIK it is just a name. However different companies sell different buffer H with slightly different concentrations of the salts, so it is not an universal name. One hast to check each supplier for details.