CharonY

The US always had a significant proportion of non-American scientists. So it is definitely not a new trend. In addition, Asians (either foreign or not) tend to value education and tend to send them to university if at all possible. For overseas Chinese the US is still a prime address, though for engineering more and more are also going to Germany. Now, China is trying to become a major player and is pumping loads of money to create state-of-the-art labs as well as trying to attract overseas Chinese back (the 100 talents program it is called, I think). In my field I noticed an increasing trend of Chinese labs (not Chinese names from US labs, there were there more than a decade ago), with a steady increase not only in output, but also in quality. But back to the situation in the US, as a rule of thumb the undergrad courses are dominated by US citizens (roughly 75% and up), however at the grad level that changes (I think it was 30-0% non US grad students across all US universities). Postdocs are around 50% foreigners. Even in faculty position around 25% are foreigners, with Indians being the biggest group followed by Chinese (statistics were from around 2005, but if anything the trend is increasing). In my group and most that I am collaborating with, the majority of postdocs and PIs are non-Americans (mostly Asians and Europeans) but even on the grad student level the US citizens are in the minority. But again, that is a trend that has been going on for decades. Other countries are actually complaining about the "brain-drain" to the US. I do not think that is accurate. Outsourcing of certain industrial branches, maybe. But academic science is still often tightly bound to the country in question. While overseas collaborations exist, it is still a far cry from academic outsourcing. How could it? Academia has a fundamentally different role than industrial research.

Interestingly, i am a bit more skeptical because of working adjacent to that, so to say. A colleague of mine is working on it and I have run a few things for them. I have access to the primary data and as such, while promising, is still some ways of from being the next big thing. It has potential, no doubt, though many (most) suggestions for improvement have not yet been demonstrated to provide benefits. Note that the last time I did something on that was roughly a year back. If something revolutionary happened at that time, I am still unaware of it.

As mentioned above, the bulk of bacterially induced changes in metals is respiration. Breathing is not too wrong as the mechanisms are very similar to other forms of respiration. Keep in mind that most metals are not present in significant amounts as either solubilized ions (i.e. free Fe3+) or in elemental form. The majority will be in a stable oxide form as e.g. Goethite (FeO(OH)) in case of iron. The respiration is just a means to power the proton pump. So the iron in the iron oxide will get reduced to Fe(II). What happens then depends on the environment. If oxygen is present it will get reoxidized and depending on pH and other parameters different iron oxides may form. Now about iron uptake. The amount is relatively low in terms of iron turnover as only relatively low amounts are required. However, in many environments iron can be limiting. The reason is the low solubility of iron oxides. However, Shewanella often does not face these restrictions. The reason is that it is also often found in anoxic zones where reduced iron (e.g. by respiration) does not readily reoxidize. Hence, they can easily take up the more soluble Fe(II). Correspondingly, they do possess Fe(II) transporters but (to my knowledge) no elaborate siderophore uptake systems. Most aerobic bacteria have no access to Fe(II). Hence they mostly produce siderophores, which are a diverse class of iron chelators that bind Fe(III) and solubilize them. The alternative strategy is to reduce them (assimilatory iron reduction) and then take up the more soluble Fe(II). Just remember to distinguish between iron uptake and dissimilatory iron reduction (which does not result directly in iron uptake but is used for energy production).

Generally iron is present as a an iron(hydr)oxide as e.g. hematite, goethite or transiently also as more bioaccesible ferrihydrite. Those are generally the most common sources.

For the most part they do not eat the metal as in using it as source of food, but rather they use it the same way we use oxygen. In essence electrons are dumped from the bacteria to the metal (in order to create a proton gradient that in turn allows the generation of energy). The reduced iron is more soluble and is susceptible to re-oxidation reactions. However, as almost any other organisms bacteria also require minute amount of iron as micronutrient. They can dissolve iron either again by direct reduction or, more commonly, using siderophores to solubilize it. That happens on a very slow scale, though.

I suppose one of the biggest problems is likely to be humans. Given the diversity of the trees in real jungles (i.e. non-cultivated forests) I assume that they are as a whole much more resistant to diseases than most forests.

Unfortunately there is still a big gap between theory and practical application. Right now biodiesel from algae are still too expensive to produce, which, among others is due to their low yield (even using GM cyanobacteria). Still, it has potential, though from the last results I have no idea where the breakthrough should be coming from.

Basically small stuff like CO2, O2 and NO can diffuse through the membrane as well as small non-polar molecules. Water does, too however the rate is higher than normal diffusion would allow. The reason is the presence of porins that are permissible to water.

Quoted for awesomeness. Also the culture series from Iain M Banks. Rebus series from Ian Rankin, the cyberpunk trilogy from Richard Morgan (as well as most of his other few books), almost everything from William Gibson, Terry Pratchett's Discworld series, Orwell's 1984 just to name a few.

I think there were studies around that supported the notion that large amount of caffeine intake may reduce calcium absorption. However, the effects were small and not reproduced in other studies (which claimed otherwise). If there is an effect, it is not a very pronounced one, apparently.

Polyploidy (i.e. addition of chromosomal sets) have traditionally been done by simple breeding rather than genetic engineering. Truth is, large scale changes are easier done by breeding than by genetic modifications. For instance, Chihuahuas and Doberman could be considered reproductively isolated. Many more examples could be found in sterile or non sterile plant and animal hybrids.

As far as I know the theory behind it is not solid enough to allow diagnoses. I am not familiar enough with it to know what is being observed and whether it has any validity, though. My question is what precisely is being observed and what is the mechanistic connection to a derived diagnosis.

They affect DNA bending and accessibility, they are targets for proteins, they may encode RNAs with various (usually regulatory) funcitons and so on. Looks pretty tangible to me.

It is largely dependent on the country. The programs vary a lot. For instance, graduate programs in Germany are shorter and are mostly focused on doing research rather than having classes. However, most entering usually have a master's equivalent (though this has been changed in recent years). As a doctoral student there were no tuition fees and you got paid for the work. Generally you should check the programs available, and either apply for open positions or try to get a scholarship. But what you get is will differ a lot from country to country.

Getting pure samples from environmental isolates is a non-trivial task and is much more complicated than simple dilution plating. However, one of the largest depositories is the American Type culture collection (ATCC). In addition simple things like E. colis can also be ordered from many biotech companies as e.g. Invitrogen or Fermentas.

To my knowledge no form of hyperthyroidism is linked to food aversion. Except general lack of appetite (though more often an increase is observed).

To run it go to computer select the drive, go to properties, tools and select check drive. Alternatively use the command prompt and type chkdsk x: where x is the drive. Cleaning the registry is not as important under win7 anymore. ccleaner does a good job though (among other things).

It has been a long while since I read Popper but I am not sure whether the OP got his position right. He maintained that falsifiability is crucial to the scientific method. It does not mean that any theory is inherently wrong, but it is inherently falsifiable. Otherwise it is not a scientific theory. It does not necessarily mean that it will eventually be falsified, though.

Moved to homework. By shortly skimming the post it appears you are correct. Well done.

Regarding raw milk: it depends on the source. Most milk is gained nowadays from industrial production in which infections are a higher problem than the traditional small farms. The main infection is actually outside the cow, i.e. the udder. In addition, people not used to it are at a higher risk. People working near animals tend to be more resistant. Regarding bacterial activities it is possible to do it with sterilized as well as unsterilized milk. Milk is a relatively selective medium and the majority of the bugs living in it in significant amounts are harmless. By adding a large amount of starter culture one can steer the production in the right direction.

Simple answer: no. Normal butter is not created by bacterial processes.

By threatening to go nucular on their apartment community? Ohh I got an idea. How about create a plant virus that gives you lung cancer if you smoke the plant? It is likely though that for terrorist organizations it is easier to get hands on chemical and biological weapon than nuclear ones. Deterrents do not work for them as they do not work along borders (for the most part). And I assume as long as their respective leaders see themselves maintaining power they won't care if their home country (if they have something like that to begin with) gets bombed into the stone age. In fact, it may actually help their cause. Unless there are also leaders of the respective countries, of course. Still, right now natural diseases are still way ahead with respect to population effects than anything a lab cooked up until now.

H2O2 does not heal, it sterilizes (by creating oxidative stress). Infected/wounded areas bubble usually because of the catalase found in serum (seeping in from the wound) and possibly blood cells. In addition fungal and some bacterial infection may also be catalase positive. But then they have to be there in quite some numbers.

Whether something harms a certain cell type depends largely on how specific the underlying reaction is. ROS target DNA, proteins and to a certain amount also lipids and can therefore harm all cell types. Viruses are not cells but basically nucleic acids encapsuled in proteins, therefore slightly different rules apply.

Depends on what you are doing. It is rare to have significant amount of contamination there as DNA does not partition well into ether. You would have to work very dirty to get significant contaminations. If you want to use it e.g. to isolate DNA for a very sensitive assays you should buy pristine bottles and keep them clean, anyhow. Point is that you won't be getting microbial or viral contamination in ether.