CharonY
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Everything posted by CharonY
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In addition to what swansont pointed out, the values you found are likely to be recommended values, not minimum requirements. So going for two weeks under the value would not necessarily impact weight immediately. But I would also assume that the biggest factor here is incorrect calorie intake assessment.
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So he thought he ate turtle but did not? And his wife is involved? Is she at the, ehm very source of a culinary misstep? In any case, I have the feeling that this is more an example of convoluted story-telling rather than a true riddle, as the premises allow for almost unlimited number of "correct" answers. Just saying.
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New tech enables crops to take nitrogen from the air
CharonY replied to EdEarl's topic in Science News
Symbiosis and parasitism are very similar in many ways. Both need to overcome host defense responses (plant defenses are generally not considered immune system, as they are functionally very different). But it is more just an infection, in root nodules (formed by the plants) they create a low-oxygen environment for the bacteria. who start differentiating into a nitrogen fixing form (bacteroid). Subsequently there is an extensive nutrient exchange between host and symbiont, which involves a very complicated interplay. The claim that this was successfully transferred between non-host systems is very bold (and amazing, if true). -
Eh, what? Other than dyslexia, how was that connection made?
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I would say that this is pretty much overwhelming evidence.
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New tech enables crops to take nitrogen from the air
CharonY replied to EdEarl's topic in Science News
Unfortunately I am unable to find any original papers (patent issues?) as the article is a bit strange. As mentioned, nitrogen fixation is nothing new per se, legume symbiosis is known very well and has been used in one for or another for a long time (e.g. crop rotation). That being said the biggest claim here is that they report a method that allows nitrogen fixation in all major crops. That would be very big news since nitrogen-fixing symbiosis is only found in a few non-legumes and we do not even know all the mechanisms yet. Transferring effective nitrogen fixation to non-legume crops have always been the holy grail of nitrogen fixation research and I am really surprised that there is now a claim for a major breakthrough with almost no paper trail. I really wonder how much of it is usual journalistic exaggeration and how much is true. E.g. if the method is really "just" an improved way to induce symbiosis or increase the efficiency of the symbiosis (both of which are would be pretty interesting, too). -
Am I too old to follow my dream and become a scientist?
CharonY replied to theroamingnomad's topic in Science Education
Networking is indeed key. One thing that I would like to add to Trimidity's anecdote, a postdoc is usually on soft money in form of grants or similar. Thus, depending on the overall lab situation losing one or two rounds of grants may result in termination. Not very attractive when you are in your 40s and have a family. In some institutions there are a handful of permanent research scientist positions, but they are very, very rare. One thing to consider is also the financial situation, if it is insecure I would be careful about an academic career. I have no personal experience with the UK system and have to rely on what my colleagues from there tell me, but a PhD (which is required for an academic career), is likely to take about 8-9 years. But even so, only after the PhD the search for an academic career actually starts. In biology we are looking at almost a minimum of 4 years of post-doc, usually with very low salary. but even 6 to 8 years are not that uncommon to get a lecturer position. In the US that would be a tenure-track position (assistant prof), from my understanding in the UK the position would be open ended. So if everything works perfectly it is likely to take more than 15 years to secure a position. But one thing to keep in mind is that there are not that many positions to begin with. The majority of postdocs will not get an academic position (though luckily most eventually find other employment, e.g. in industrial positions, at least in my field). The average academic position (tenure track) has about 200 applicants, for example. In order to get that position you need more than a little bit of hard work and giant chunk of luck (though a strong network will optimize the latter). I am not trying to be too negative here, but the point is that even if everything is done correctly and one graduates on top, the chances of securing a career are bad to begin with. To give a number, before the economic crisis less than 20% of all PhDs staying in academia got tenure but that number is likely to be lower by now. I would not even think that age is the biggest challenge here, although it does not make things easier. A potentially better choice is too look for jobs outside academia on the masters level, e.g. as analyst or technician. Especially if you bring real-life experience outside of academia to the table you will look more attractive than the 20-something who has not stepped outside of school yet. -
I am pretty sure about the inability of B. cereus, but I would have to look it up for B subtilis. Yes, you are correct. However, colony and cell morphology are somewhat distinguishable between those two as an additional factor. But that really only helps if you got a reference or experience with them.
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Was the Law of Conservation of Energy ever proven for electricity?
CharonY replied to Windevoid's topic in Speculations
How so? -
Depending on strain hemolysis is sometimes not terribly strong. Are the cells motile (B. cereus)? Another test is the Voges-Proskauer test (B. megaterium, would be negative, the others positive). But that being said, I am pretty sure that B. cereus does ferment glucose anaerobically. However, they still grow very poorly if the medium is not very rich (which may lead to false negatives).
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Am I too old to follow my dream and become a scientist?
CharonY replied to theroamingnomad's topic in Science Education
With regards to employment, the question is also what type of position you are thinking about? Academic positions are highly competitive (age or not) and securing a position there at all is tricky and it does not look that it is going to be easier any time soon. i think the first thing is to figure out what type of jobs would be interesting to you at all (as there is no such thing as a generic science job, and even biology itself has vast variety). Getting contacts is always a good start, though I am not so sure whether websites are a good tool for that. But a quick thing to do is e.g. looking at naturejobs or the equivalent on the Science website to get some rough ideas what types of jobs there are (but also other job listings may be worthwhile). -
To come to this conclusion the chief element is an inflated ego. Inflated ego and ignorance. The two elements are an inflated ego and ignorance and laziness. The three elements are an inflated ego, ignorance, laziness and the inability to deal with criticism... Amongst the main reasons are elements such as.. I should stop now.
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The thing is that it is almost impossible (at least with our current knowledge) to accurately deconvolute the influence of environment and genetics for all but the most simple traits. For IQ the estimated values range wildly and also change with age. I.e. it appears that (contraintuitively maybe) at early age the measured heritability is low but increases with age (see Bouchard 2004; Curr Directions in Psychological Science). From my perspective (which is biased towards molecular biology) a mechanistic link is needed, before we can be certain of the actual contribution. With regards to families, there is also a strong influence on environment for that. A family that values sport is more likely to be more active in that regard, for example. I am not saying that there is no genetic influence, as there certainly is, but there is no simple 1:1 attribution of a genetic trait with the physiological outcome. Many factors have to come together and especially at the top level time investment becomes more relevant. You will not become a world pianist just by having good genes (say, nimble fingers of sufficient length, good hearing etc.). You will always need an enormous amount of practice. But as a thought experiment. let us assume that there are some genes that promote musicality and as a result one person needed less training to become good, and another one needs more. But both finally master the art. How would you look at their performance and quantify the contribution of their respective genes? What is more likely to happen is that "designer" babies will end up with certain desirable physical traits (say, eye color) and absence of markers for certain genetic and maybe even reduced propensity for certain other diseases. But do not expect the genes do the work for you. If you spoil the kids, they probably end up being lazy-ass couch potatoes (but who knows, maybe with lower risks of cardiac diseases).
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The idea is not bad however this has been tried out for easier traits (IQ is highly complicated in that regard) such as diseases. And it does not work out very well. The reason is, as I mentioned that few traits can be strongly linked to a single gene or group of genes. Especially something like IQ will dependent on a large part on environmental queues. Think of it that way, even if there was a gene that influences IQ (and if there is, we do not know how it does it), if you raise the kid alone in a dark room it will likely perform far less well than an "average" kid with a more interactive upbringing. I am also pretty sure that if you analyze the allelic variants between world-class sprinters and average people, you will find no genetic signature that explains that difference (and so on).
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In cases of mobile genetic element the site-dependence is actually more on the side of the element (e,g. type of transposase) and is therefore in principle not that tightly coupled to the host line per se. Also note that certain areas that have low mutation rates may not be mechanistically protected, but if they are negatively selected against, we won't find them easily (or not at all, if they are fatal).
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This is very speculative and I will move it appropriately. I think this is the crucial question and I am not sure whether we actually ever can. Is an enzyme variant with 2.5% higher activity better or worse? In biology things are heavily interconnected and changes that you may consider positive in one isolated network and condition can have detrimental on others. There are extremes where you can easily notice impairments. But on the other side of the spectrum it is far murkier. In the end it all also depends on the environment. Certain allellic variations may be more beneficial when growing up and living under certain condition than in others.
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chomsky.info? What a perfidious way to hide information.
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Where can I get my whole genome sequenced and put in easy data format?
CharonY replied to steviek2000's topic in Genetics
Note that in area of biomarkers for many SNPs only association studies to diseases and conditions exist. I.e. there is no known mechanistic link between an allele and a given phenotype. Thus, many of the predictions are false positives, and I believe I read somewhere that 23andme heavily overhyped these associations as a marketing push. -
Me thinks that that OP has not read the posts that have been put forward. No one is contesting that new information came about and it has been known for a long time that many tenets of the modern synthesis simply never held universally. Just try to apply the species concept to prokaryotes, for example. Nonetheless they were kept around because simplifications are common when you develop models. The big questions is always how much you can leave out and have it still being useful. Looking at the body of publications coming out since the 40s in evolutionary sciences, I am pretty confident that it held out pretty well. Also note that specialists in their field do not simply follow a paradigm blindly but adjust things according to the subject of their study. No evolutionary microbiologist would even mention reproductive isolation, for example. All these things mentioned in the paper/talk have been around for decades, and not something we just found out. But so far no one is able to integrate all the knowledge in a useful manner. And neither does the author. As everybody is pointing out, just renaming things does not revolutionize it. Improve it, then you get to talk. (As a side note the dogma of molecular biology already got long int he tooth when I studied, and as many things in biology, it is just a convenient convention, in this case a simple model to teach proteinbiosynthethis. And it is hard to argue that it has been very successful). And as I said before if you look at the literature, pushes to have a new modern synthesis been made pretty much since we started with genomics (let us say, around the 90s) but there is no integrative model yet. And Ophiolite makes a a good point (again) that in some cases (and political climates) keeping well known names has its advantages. I will repeat myself: due to their complexity biological (and other complex) models are never fully accurate. The real question is always whether they are useful. People preoccupied with naming conventions are IMO valuing style over substance.
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Here is actually a nice paper visualizing spread of necrosis during organismal death of C. elegans http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001613;jsessionid=4D4839531B36A2C822047D1B4B15EBC4
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A few questions about memories
CharonY replied to chamin's topic in Anatomy, Physiology and Neuroscience
1) Memory is not likely to be complete false, but just inaccurate. It will depend a lot on how important the details were to you when you experienced them and whether you recall them frequently. That being said, inaccuracies in memories are very common as memories are reconstructions rather than photographic snapshots of events. Check out this Ted talk for example http://www.ted.com/talks/scott_fraser_the_problem_with_eyewitness_testimony. For the other points, there is quite some research on memory and among the things that have been reported include emotional involvement or novelty of the experience, but it would be way outside of my expertise trying to summarize everything. -
Aha! But has anyone tested whether the laws of physics work the same way in his multimeter specifically?
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And as Ophiolite pointed out, from the viewpoint of anyone even tangentially involved, it is not new, but overdue. I have to add that the viewpoint presented in the paper is still insufficient. Essentially it argues against modern synthesis (which many did over the years) and promotes a different viewpoint. What is needed however, is an integrative view (a theory of everything, if you will) that, (and this is the critical part in my opinion) provides more quantitative information of the respective aspects. Yes, there are epigenetic factors involved in, but what is the quantitative contribution relative to the other factors. How does it shape rates, for example, how much do existing models have to be changed? Do they have to be changed at all? Often times the molecular knowledge is not quantitative enough to assess that either, for that matter. And going back to the novelty, as Ophiolite already mentioned a first big push (that I still remember) came from the evo-devo area and there quite some papers around the 90s for a new modern synthesis, quickly followed by a large number of publications from the area of microbiology (as they were more or less left out from the modern synthesis and just did their own stuff)/ So as it stands it falls into a long line of arguments which I hope will eventually be married to more integrative approaches. Interesting? Yes. Revolutionary? Probably not.
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Pretty much any form that disputes the occurrence of evolution.