CharonY

In order to see a complete growth curve including lag, growth and stationary phase the experiment would have to run for several hours.

The first experiment can go wrong due to a number of reasons. Without knowing the precise setup troubleshooting will be difficult. But some things to consider: - was the initial count accurately determined and how - were the cultures fresh - was the dilution series made correctly, was the right buffer used - was the medium OK - did you let the scraper/spatula/whatever cool off (if heat sterilization is used) before plating the cells? Regarding the second experiment, in the time frame that you measured (90 minutes) you cannot expect a growth curve. Even fast growers like E. coli or Shewanella have replication times of around 25 minutes under optimum conditions. So at most three cell divisions could have taken place in that time. However, depending on how and when you inoculated the batch you will start with the lag-phase (also the OD is already pretty high in your graph). And the results clearly indicate no growth as the changes are only minimal and can be easily the result of pipetting or mixing errors.

As I mentioned before, intuition generally only yields useful results if the required knowledge base is there. How much really may be necessary depends on the complexity of the problem at hand.

There is better data for overmedication in well (or at least better) defined areas. That is, where risk-to-benefit balances can be relatively easily done. This include for instance epilepsy treatments. But in the area of mental illnesses it is hard to quantify benefits of certain medication.

You could also use sterile swabs or pipette tips in lieu of an inoculation loop. Or toothpicks, if you blunt and sterilize them. The key is to make sequentially diluting strikes as pointed out above. If high titers are expected I would do it slightly differently, but the principle is the same.

From what I have read we are quite farther than 30 years ago. At least in terms of finding out what we still do not understand.

Watching ants at their nest.

Your definition is quite correct and basically you already got the answer there. Think about it for a second. A low ID50 means that a low number of organisms are required to cause the diseases (in 50% of test subjects). So what does it mean if you compare it to a disease with a high ID50?

Intuition without knowledge is just random guessing.

Cell lysis can be achieved by cooking, though not really by enzymatic actions. The latter can be used to destabilize cell walls and similar structures but the membrane remains relatively intact. An additional step as e.g. chemical, mechanical lysis is subsequently required (or cooking for that matter).

To the OP, while I was in Germany I never heard about that campaign (was around 2001 according to the article). And just btw. the linked website is quite odd with a few spelling errors in German. I would have to see whether I can find anything more news-like on that. Nudity in public can be considered persecuted if someone is offended by it and calls the police (the police does normally not actively act if they see someone walking nude through the street). Usually it carries a small fine. I recall the story of a guy who always walked naked through the streets and claimed that his body was art. Some (mostly elder women) tend to call the police at some point, where he has to pay a fine and cover up. Quite often no one bothered, though. The only time when he had serious trouble was when he undressed in court and got sentenced for contempt of the court. Generally public nudity is considered impolite (unless in nudists camps, although you will also see women topless on regular beaches) but you will see it regularly in ads as well as on TV. Primary sexual organs are generally not allowed to be shown on TV or ads except e.g. for teaching purposes.

Depends, in principle it is fairly straightforward. What kind of mircroarray are you refering to and for what purpose? I.e. transcriptome analyses with a DNA microarray, DNA identification, tilling, protein microarrays, etc.? More importantly though, do you include the time needed for the upstream (i.e. properly experiment planning, RNA isolation, if applicable,etc.) as well as downstream analyses (i.e. data analyses, statistical assessment, modeling, if appropriate). Also you do not master the technique, the technique masters you

The flow is too low and the vaporization to mild to allow for anything like that to happen. In LCMS, for instance you pump in and vaporize at most 1-2ml/min of your solvent (which is often flammable like methanol), without anything happening. And then you add a minute amount of your sample. The most you could do is mess up the ion source (usually by using unfavorable conditions and way too much substrate). And just btw. depending on substrate and ionization you can also easily yield negative ions. You can run any MS in negative mode, which basically just requires a switch of polarity. Merged post follows: Consecutive posts mergedJust to add, apparently someone did manage to mess up his MS in a liquid system. Apparently a non-standard mobile phase (not further specified) was used that resulted upon heating into a volatile reaction. Of course the volume were too low to blow anything up but apparently the resulting products were covering the whole ion source. But again, it was not the analyte but the mobile phase.

The public should want to know the truth. However, most of the time the public really wants a reaffirmation of their respective opinions. Padren, sadly it does not really read like satire.

I actually recall that a while back a group actually cloned the genes into E. coli and tried to create spider silk heterologously.

This is an interesting topic. It should be pointed out, however that cohort studies only provide associations and by their very nature can lead to conflicting results. It is therefore very important to check more than one study and ideally find one that demonstrates mechanisms. A quick search revealed that there are studies that find that there are indeed conflicting results. The most recent one being Zhang et al. 2009 Alcohol and Alcoholism, doi:10.1093/alcalc/agp068

You have to keep in mind that the H1N1 variant is just a different Influenza A strain. The basic sequence has long been published. You are probably more interested in more detailed analyses of the differences between the strains. There are a couple out there including the one posted here: http://www.scienceforums.net/forum/showthread.php?t=41872&highlight=h1n1 Also for starters you may want to check a recent review. The author was Schnitzler, I do not know the complete reference off the top of my head, though.

What do you mean with genome map? The annotated sequence has been published earlier.

So much for short. Anyway just to continue the thread: The easiest explanation for the discrepancy is that the majority of mutations are not beneficial. The earlier increase of fitness is possibly due to rapid adaptation to the new medium, but after that the continuing mutations will be (near) neutral. The initial beneficial burst would then be overshadowed by the continuing accumulation of neutral mutations. However the authors found several aspects that would contradict this scenario. First, if the majority were neutral mutations, one would expect a higher frequency of synonymous mutations (i.e. mutations that do not translate into a different amino acid). In fact, the authors found that all mutations in coding regions were in fact non-synonymous. Second, if the spread was due to random drift then one would expect different mutations in the different cultivations. However, in 11 independent cell lines a high proportion of similarities were found. Third, if drift was a major factor (as opposed to selection) then many occuring mutations are unlikely to be fixed in the population. However, mutations were found to be persisting through time (they froze sample throughout the generations to be able to track changes). And finally they generated strains artificially with the same mutations and found that at least8 loci actually did confer fintess advantages (and were therefore not neutral).

Actually I do not think that is what is meant. Beside the fact that such short primers are usually not very useful and that the ends will be different. Just from memory XhoI recognizes CTCGAG but generates sticky ends, i.e. 5'C TCGAG3' and 3' GAGCT C 5' respectively (as mentioned above). However, EcoR1 recognizes GAATTC and cuts between G and A (again sticky ends): 5'G AATTC3' and 3'CTAA G5'. The space indicate cuts. What you normally do is that you know the sequence beforehand, then you digest the DNA virtually using the above information and see what fragments are expected. In addition it yields a little bit of sequence information, but this is most of the time obsolete. If the fragments in question are cloned into a vector for sequencing purposes (using the double digest), then the primer will normally be generated based on the flanking sequences of the plasmid, rather than starting off with the restriction site. The reason is that longer primers ensure a higher fidelity of the product and the fact that polymerases work better with a certain minimum length (routinely 18-20 are used). In the end I do not really understand the question in the OP. It sounds to me that the purpose is a restriction analysis of a vector but why would primer be necessary? In order to sequence a whole vector, depending on its overall size it would be fragmented (which can be done with restriction enzymes) and subcloned into sequencing vectors. One can also do thinks (albeit with lower efficiency) like primer walking. But I do not really believe that that is what is meant.

Essentially yes. "Motifs", however are used in again a different context, so it may not be optimal to use this term to describe it. The secondary structure tends to refer to the structure of local segments. It can also describe the totality of said structures (e.g. proteins x has so and so many alpha helices) but it does not refer to the complete interaction within, or between polypeptides and proteins. Thus one would not normally use primary, secondary etc. structure to classify protein (e.g. protein x is a quarternary protein), as this does not really make sense, but one could state that the quarternary structure of collagen consists of three chains twisted into a helix. The secondary structure of collagen consists of a triple helix (ignoring the fact that several peptides are involved). An easier way to think of secondary structure is to refer to it as the spatial arrangement of the peptide backbone while disregarding side chain interactions. Normally a quarternary structure would be dependent on the side-chain interaction. The case for collagen is somewhat complicated due to the unusual triple helix which just does not require that (though they add to the stabilization of the fiber).

Well the formal definition of quarternary structure only refers to the interplay of polypeptides but does not include any necessary complexity. It is easier to see it if thinking hierarchically. The triple helix is a secondary structure. It is a local structure. The whole complex however, would be described as a quarternary structure. It does not matter that the whole protein complex is merely consisting of helices.

Proline is special due to two reasons, first it lacks an amide hydrogen therefore the backbone hydrogen bonds for the carbonyl groups at positions (i−3) and (i−4) is missing. Secondly the proline ring destabilizes the backbone by increasing the helix rise in one turn (to avoid the carbonyl group at position (i−4)). Both elements destabilize the alpha helix. This is actually important for certain functions, especially of transmembrane proteins.

It does not refers to stages of a protein but to the different complexities of its structure. Every proteins has a primary structure, which is the pure amino acid sequence. If the amino acids would not interact, that would be the end of it. But essentially due to hydrogen bonds they form up secondary structures like helices or beta sheets. A long protein can have many of those. The secondary structure essentially refers to these local conformations. But there are other forces, including ionic or hydrophobic interactions and disulfide bonds that can further determine the structure of the protein. This is then referred to as the tertiary structure. The proteins does not got through stages but these are just different levels of complexities to describe the protein. As the amino acids alone will normally interacti with each other, native proteins will all have a tertiary structure (and implicitly also a secondary and primary) unless you denature the protein (i.e. break up all interactions either) which causes the protein to lose its tertiary and secondary structure. The quarternary structure refers to protein complexes in which several proteins or polypeptides interact to form a superstructure. A single polypeptide can have any amount of helices. It only depends on the composition of it. Yes, it consists of serveral polypeptides interacting with each other.

The critical point is when it injects its saliva. That is when the transmission of bacteria or viruses occurs. Moreover, if you injure it or squeeze it during removal it may actually continue or secrete more, that is why it is recommended to remove it carefully. In addition to Lyme disease caused by Borrelia burgdorferi (which is quite an interesting bug for several reasons) they may also transmit a number of other bacteria and viruses that cause encephalopathies. That being said depending on region the ticks are more or less likely to transmit diseases. That is something you may want to look up. Also if there is no reddening of the bite, it is possible that he did not hit any blood vessels, further decreasing the likelihood of any infection. If you develop a rash or any other persistent symptoms you should seek medical attention and mention the tick bite. However they can take quite a while to develop. And finally,