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CharonY

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Everything posted by CharonY

  1. Do you need the theoretical proteome (i.e. derived from the genome sequence) or expression data? For the latter I am not sure whether 20 have been published (I doubt it). Even with complete genomes I am not 100% sure, though JGI for instance has been churning out a lot of bacterial sequences. You should take a look at the ncbi servers.
  2. I assume you mean calcium competent cells (there are different types). The basic protocol is the same for basically all strains, though there are modifications. Most of the time they appear to be more rooted in lab culture rather than real-life increase in efficiency. I do not know the precise protocol off the top of my head, but I am pretty sure you can find it quickly via a simple search. For more details I would advise reading Sambrook's Molecular cloning. The basic premise is always growing the cells to the log-late log phase, harvest, keep cool. Then wash with CaCl2 solution containing glycerol, pellet cells again, and resuspend in reduced volume, and quickly freeze them.
  3. Isolating a pure culture from environmental samples is extremely labor-intensive. If I were you I would try to order it from a type culture collection.
  4. I tried to link Mendeley with Endnote but had serious problems. Also when trying to use it to reference papers it sometimes garbled up the author order. Though the newest iteration may have improved.
  5. Actually not education guarantees a job (not even a lousy paying one). It only gives you skill that can make you more competitive. In the end, education is only a part of the equation. A phD opens up certain job opportunities (and closes off some others), for instance. However, one still needs a strong career development plan, which does not come with the education package.
  6. It is based on phylogeny. I.e. their relation and common history (and where the diverge). An simple (but somewhat inaccurate) analogy would to declare someone as your cousin because you share a common history (e.g. one of your parent is the brother/sister of one your cousin's parents. It is not based on the fact that both of you may have uncle Willi's nose, for instance (though you may actually have it).
  7. The one carrying a gun, I presume.
  8. Well with regards to essential amino acids, humans have lost the ability to synthesize roughly half of all amino acids. Also note that some essential amino acids can be synthesized but not in sufficient amounts (and have to be part of the diet).
  9. None of them produce anything. Both are involved in gas exchange, though the main function in plants is the delivery of oxygen and CO2 transport probably does not play much of a role. The reason is that leghemoglobin is necessary to deliver oxygen to symbiotic bacteria. However, the bacteria are there to fix nitrogen and they can only do it at low oxygen concentrations. So the leghemoglobin has a very strong binding constant (higher than hemoglobin) in order to ensure an extremely low amount of free oxygen, but still ensure delivery to the bacteria. Other than that the functional groups are essentially the same, but the overall protein structure is different (both on the sequence and somewhat on the structure level). Both belong to the same protein family, though.
  10. Compare in terms of what? Functional groups are similar, though there are significant sequence differences.
  11. You would want to know what you want to get rid off, also the parameters of the water should be taken into consideration.
  12. Human flora is a bit tricky as we carry a lot of opportunistic pathogens around. At low titers they are harmless, but cultivating them into high amounts may pose a problem. Using rich media as LB you are more likely to grow fungi rather than bacteria, most of the time. Getting pure cultures of anything is a completely different beast. If one wants to do an identification, it is probably far easier to amplify 16s and sequence it (which does not require much of an enrichment).
  13. According to this unemployment rate differences between women and men can be explained by the different jobs they hold. Also I am wondering whether stay-at-home moms are counted as unemployed (I should check out the methodology). More to the point, according to the last statistics I have seen women are still underrepresented in top jobs and receive lower salaries in similar jobs. I would disagree with several points. It is true that there is a high emphasis on education in Asian communities, often paired with strong work ethics. However, increasing number should not be an issue, Asians are still a relatively small proportion of the overall population. Also I do not think that most Asians are elgible for free tuition. In fact, most Asians in universities I have encountered are foreigners. IIRC something ike 50% of all postdocs and 25% of faculty in the US are non-Americans, with Indians and Chinese being among the top groups (numerically). That being said, I would agree that in most cases affirmative action based on social backgroung rather than ethnicity makes more sense. In many cases they are at least somewhat coupled as in many cases individuals above a certain income (or parent's income) are not eligible for certain stipends. There is, however, another aspect to it. How is the selection process? Ideally one would say that it goes to the most talented from a pool of low-income students. However, as several studies have shown in different countries the very same essay can be graded differently depending on the student's name. That is, if they sounded foreign or, in case of the USA had names associated with the black population, they earned lower scores. Personally I would prefer a socially based, double-blinded selection.
  14. Right. in that case Germany could have gotten involved, if they wanted to. Though It would be a tough act after their their resistance to enter the war in the first place (and the resulting falling out with the US). More to the OP, however, at the time of the discussion there was not mandate to invade Iraq. Legally at that point the chancellor could not have provided troops, even if he wanted to. Note that he also supported ongoing inspections by the UN.
  15. Though I have to add that bio is in decline, whereas biomed is taken over by medical sciences, biochemistry, engineering, bioinformatics and, yes, biophysics (though the latter is rather small addition). To me it appears that classical biology and genetics is in a rapid decline. More engineers are funded for the assessment of health effects of pollutants, for instance, than biologists. The reason is the same, though. Understanding biological principles does not quickly lead to applications (something that the NIH is strongly interested in).
  16. Also the German constitution generally does not allow Germany to enter an attack war, unless it is under an UN mandate. Since this was not the case, the German government would not have a heap of legal troubles sending troops in (with the possible exception of medics). Theoretically they could have been allowed to conduct peacekeeping missions afterward, but the government could then be made complicit to an illegal war. The main point, however, is that without an UN mandate it would have been almost impossible for Schroeder to assent to sending troops in.
  17. BibTeX is quite nice, Zotero (a firefox plugin) is free and very useful. Generally I found that indexing all read papers makes little sense as the library becomes so big that after a short while it is often faster to search for certain papers online again. I do have harddisks with several gigs of papers, though.
  18. Well theoretically there is very little potential for active viruses that are beneficial. The reason is less in their destructive nature but due to the fact that their genomes are already extremely strained just by the necessary genes to replicate. In fact, they stack their genes and make use of slippery transcription to express them all. In order for them to be beneficial as such they would have to introduce new genes or alleles, for which there is little room. The only exception is the mentioned transduction event. While the result is a gene transfer event, usually it also renders the virus inactive (as part of the genes necessary for viral replication are replaced). However, integration of the virus into genomes themselves can lead to mutations that over long or short can result in a fitness increase. During longer co-evolution the viruses tend to become inactive, or at least less destructive. In terms of fitness from the viewpoint of the virus you can imagine it like this: - a virus that eventually kills its host and spreads aggressively will proliferate in short-term, but may run out of hosts - a virus that spreads passively and eventually becomes fixed in the genome will have maximum spread in the population but it takes longer
  19. So you worked on half of the magnification as the others and did not notice it? That is all? One difference in grad school is that you are self-responsible for all the equipment you intend to use. This includes a basic understanding of how a microscope works and what the setup of the one you use is. This generally falls under common sense. Just because you are in lab, it does not mean that you are allowed to turn off your brain. If you think of it that way, you missed the point of doing a class.
  20. Did the possibility that part of it may be on your end ever cross your mind?
  21. The gold standard is generally to compare it to a placebo group.
  22. 1) It is going to depend on what organism you are using, and of course, none of them are truly safe. They are carcinogens. Generally I would go for UV (which is easier to handle, if one does not have a training with hazardous chemicals. This can easily be used on e.g. E. coli.
  23. I can clearly see the rant, but I fail to figure out meaningful questions that I could answer. At least not in a way that would satisfy you.
  24. Well, that is one of the main problems of species definitions. In prokaryotes sequence identity of 70% (IIRC) as detected by DNA-DNA hybridization was considered to be a gold standard to distinguish species. Nowadays this is corroborated using molecular biological markers. The morphological species definition is highly problematic and usually only works somewhat when certain traits are used that have been well characterized in a phylogenetic context. For most asexually reproducing organisms this is most likely not the case.
  25. Think in terms of what you need to grow a whole organism out of everyone. Also compare spores to seeds.
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