CharonY

That is precisely the point. The hypothesis that certain areas have to be stimulated in a very specific way is most likely false (or at least there is no support for it). However, the big question is what placebo really is. It is an effect, as it has physiological consequences. More likely placebo may actually be a variety of mechanisms, and lumping them in a common catch phrase may actually make it harder to precisely define it.

Ah, in that case it really looks like salt contamination of sorts. If the buffer already has different conductivity it is a source of concern.

Most likely it refers to the analysis of protein expression under different conditions. E.g. a cell line under normal conditions (whatever is defined as normal) and the same cell line exposed to some kind of stimulus. Or a comparison of wild-type to mutant. The test then shows whether the protein(s) under investigation are expressed at different levels and are hence affected in their regulation by the stimulus/mutation.

Moreover many animals including crows, monkeys and apes show culture (i.e. transmitting learned things from generation to generation). The assumption that humans are somehow special compared to other animals is based on an anthropocentric view, rather than on hard data. Not to mention the general problem in defining what consciousness is at all. How can we test other species when we are not sure of the mechanism in ourselves? Finally, regarding instincts. It is unfortunately a word that has been heavily misused. In the simplest sense it refers to innate behavioral pattern. However, almost all animals show the ability to learn. Except for very simple organisms their behavior is clearly not only instinctive.

Not that many good ones, unfortunately. At least to my limited knowledge. I dabble into these matters every now and then as I found it quite interesting, but have not found any definite studies. Also much less that delves into the fundamentals of stress or pain perception. Or rather there is a lot, but there is a knowledge gap between mechanisms (also on the neuronal level) to the perception part, on which placebo (or whatever) could work. It is another typical case of insufficient biological knowledge to allow definite answers.

It is quite possible, even likely that the placebo effect plays a role. The original theories behind it are clearly non-scientific (or at least have to my knowledge not put into a modern model with explanatory powers yet). The problem with these uses (pain control, sleep, etc.) are highly affected by the placebo effect. A quick overview of the published papers with trials showed that the placebo effect was mostly not accounted for (e.g. Chen et al Int J Nurs Stud. 2012 Mar 3). In at least one case acupressure was only simulated by touching rather then massaging ( J Midwifery Womens Health. 2012 Mar;57(2):133-8). But if te placebo is due to general massaging (and associated prolonged contact), it would still be an insufficient control. Finally a short study showed that acupressure, placebot-acupressure and relaxation CDs had similar effects for stress reduction: (McFadden et al. Complementary Therapies in Medicine Volume 20, Issue 4, August 2012, Pages 175–182). As a general note, the complexity of pain, stress etc. makes it really difficult to distinguish "placebo" from "real" effects. If lying down relaxes you and thus reduces pain sensation, is that a placebo or successful intervention?

That is a very generic phrase. It essentially mean proteins being expressed at different levels. It can apply to all kind of different contexts, i.e. without further info it is virtually impossible to discuss it more.

Yeah, sounds like there is still stuff on it. Is the backpressure ok? Otherwise I would rinse it with several more column volumes of water and check whether baseline (I assume UV in your case?) is stable (as well as pH). If the contamination are precipitated proteins (as e.g. indicated by random UV signal) or lipids, additional wash steps might be necessary. This may include protease treatments or, in case of lipids and hydrophobic proteins, washes with compatible mild organic solvents (often ethanol/isopropanol).

IIRC it is a pBR322 derivative with nothing terribly fancy. As such Top and DH5alpha should both be fine. Main differences are found in the methylation/restriction systems (and recombination apparatus).

Well, technically yes. I never really used the Lancefield classification (as I come from the molecular side). Technically the Lancefield system groups are based on the detection of specific carbohydrates in the cell wall, not on their hemolytic activities. While it was supposed to classifiy streptococci, though some misclassifications (i.e. the mentioned enterococci) occured. In any case the D group are generally alpha or gamma, using the hemolysis system. I.e. these are two unrelated classfication systems that look at different properties. Also the name of the researcher is Rebecca Lancefield. Not lance field.

Unfortunately especially in academic settings this is what you get when you follow your interests rather than market demands (and trying to figure out the demand in academia is pretty much a networking exercise). But yeah, job prospects (esp. in academia) are generally not good with a kind of limbo state between graduation until the time where you can actually settle down somewhere (often close to the 40s and above, depending on the academic system). Also, you seem to be in the same spot/mood as every (non-naive) postdoc is going through. Or at least those that are not heavily promoted by prestigious advisers.

IIRC Lancefield Ds are weakly to non-hemolytic.

Also in addition to having ruined your clothes, they will also smell nicely of stuff that has been autoclaved. Especially nice if the autoclave is also used for inactivating bacterial cultures.

One problem with organic agriculture is the precise definition of what is allowed under this label and what not. For instance, pesticide use is allowed although many (but apparently not all) synthetic ones are banned. Health effects are incredibly hard to assess and it is usually not possible to de-convolute effects of food and exposure from other parameters that affect health.There are (contested studies) that look at the effect of certain types of organic agriculture on biodiversity and sustainability, for instance (e.g. Maeder et al 2002, Science). However it appears that more data is needed to draw conclusions. The results vary quite a bit depending on landscapes (see Wingqist 2011 J Appl Ecol), the scale used for assessment (see e.g. Gabriel et al 2010 Ecological Lett, IIRC) and environmental conditions (e.g. droughts). Then some proposed to re-introduce certain principles to modern agriculture in order to increase efficiency. In short, again a case of complex problem and no simple answers, confounded by the way the "organic" is actually implemented.

What is the difference between an active and an inactive metabolite?

The null is not clearly formulated. I.e. what is meant by "same"? From the way you described the experiment and the respective statistical tests it appears that you formulated three nulls (i.e. one for each concentration). In each case the null would be that at the tested concentrations (let us call it c1, c2 and c3) the compounds x&y have no effect on z. In other words, each test requires its own null. Alternatively, one could apply statistical tests that account for more than one group (e.g. ANOVA). Thus, the null with c1 and c2 cannot be rejected (i.e. we do not know whether it has or not). Whereas the null with c3 can be rejected. I.e. at c3 there is a significant effect on z. As already mentioned, a null is never accepted, we either reject, or fail to reject.

Another fun accident: grad student imbalanced the ultracentrifuge. For some reasons the centrifuge did not shut down (maybe something happened to the vials during spinning and caused the imbalance only after a high speed was reached). Result: the rotor (a heavy metal thing with roughly 30 cm diameter), punched through the centrifuge, though the plaster wall of the room and embedded itself in the concrete wall in the next room. Lab course: after telling the students that acetonitrile is toxic one girl decided to drop the bottle of acetonitrile that she was toying around with. Cause, you know, she did not want to poison herself. Of course the bottle shattered.

Just some random memories from student's labs: a student set himself on fire while sterilizing equipment with ethanol and heat (hooray to cotton labcoats). The only time I was legally allowed to tackle a student and throw him to the floor. I could not convince everyone that the best to put it out is to kick him once wrapped in the fire blanket. Another dropped over two liters of KMNO4 while trying to refill a tiny bottle from a considerable height. No white labcoats to be found in a largish diameter. Dropping a large bottle of mercaptoethanol. The lab smelled for weeks afterwards. Another one filled a mix of H2O2 and H2SO4 into the waste bottle but used the non-vented cap and closed it shot. I saw it boiling up and slammed down the hood before the bottle exploded.

I think you misread the paper. Zinc deficient strains had five times less zinc as compared during growth during replete conditions. That being said, it is expected that normal cells accumulate nutrients, how else are they going to survive? What they measured in the end is that they found more total zing than they added, which is indicative that there was contamination after all. Finally, they were mostly interested in finding elements of zinc transport as e.g. ZinT. I.e. genes regulated in a zinc dependent way. To figure out whether a mutation exists that e.g. upregulates ZinT higher than WT would require a different set of experiments.

There are a lot of misconceptions in this post, also misquotation. Let me just point this out. The original quote is a bit longer (also note that this is from the 60s): The latter part bluntly refutes

Evolutionary effects are not going to play a significant role in the presented time scales, unless they only require very small changes. The goal of this paper is to figure out molecular mechanisms that cope with extreme conditions. If you apply mild ones, many effects can mask the mechanisms you are hunting for. Extreme and well-defined cultivation can better elucidate adaptations, although you are correct that in some cases effects may occur that do not occur in nature. Yet, one should keep in mind that growing under replete conditions as found in the lab, is actually much more unrealistic than hunger conditions. In nature, hunger is more likely that normal state as each bug is competing ferociously with others for limited resources. Note that there is nothing like an adaptive pressure as your post implies (i.e. if faced starvation the chance of occurrence of a super zinc acquirer does not increase, only the spread of mutations that may result in it, which is on a different time scale). There is a certain selective pressure, but the base assumption is that the cells are already adept at acquire low level of zinc. Whether that is true for E. coli or not is rather a physiological discussion rather than an evolutionary one. If we assume mutation, the most likely one to actually affect the physiological state is within the regulatory mechanisms and it may be true that some mutants have spread that actually express higher level than the WT under the same condition. But then this study is aimed at finding targets using semi-quantitative approaches, and is not a quantitative inspection of the regulatory network.

For better reproducibility it is easier to measure zone of inhibition, or count live titer after a defined exposure of a given culture.

Highly relevant bit. Regarding species: as it has been explained numerous times by Arete and others, nature does not create strict boundaries. They are sometimes there, but then often times not. Just look at prokaryotes trying to find hard species boundaries is an exercise in futility. As such Arete is absolutely correct in saying that the delimiters are somewhat arbitrary. But, and that is the important bit, even if they do not reflect nature perfectly, they are useful. This is a basic thing that all biologists are aware of.

The distinction of man-made and natural is arbitrary to some extent. E.g. are current crops and pets that have been bred by humans natural? For legal reasons genetically manipulated organisms are classified as such (i.e. GMOs). Tthe extent of manipulation are generally very minor, as we are not able to really create living organisms (yet).

Xitenn, I am not sure I understand your point. However I would say to an interview you should be at least one step above the attire of the organization you want to join. But not based on your own level. I fail to see the dishonesty of that. A suit or other work clothes are a type of uniform. What you wear to a job is supposed to reflect well on the organization, and not on you. An in an interview you are expected to go a step or so above that (at least).