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CharonY

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Everything posted by CharonY

  1. I am not sure what the things you propose would be good for (or maybe you have a different idea what a biosensor is and being used for), as easier tools exist for these purposes. There are biosensors in development e.g. for certain pollutants. But their use is still somewhat tricky as they require live bacteria or in some cases on intact proteins. Field use is not impossible but often more error prone than alternatives, should they exist.
  2. Partially correct. However the GTP pool is usually far below that of ATP (usually one order of magnitude or more) during a wide range of growth rates. Overall the nucleotide equilibria are maintained over quite complex circuits and not just over a single direct pathway (also as a sidenote NDK is quite promiscuous in vitro which complicates matter a bit). There are other regulatory elements that appear to have stronger influence on the GTP and ATP pools. NDK is an important modulator, but it appears more to be a modulator between the pools. The effects of NDK mutants are interestingly more pronounced in pathways involved in nucleotide/DNA synthesis rather than energy metabolism. At least partially this is due to its ability to transfer gamma-phosphates between different di- and triphosphates (rather than exclusively between ATP and GTP). Thus, a mutation alters ratios at various levels kicking a metric ton of regulatory circuits on various levels. Thus mutation affecting ATP synthesis and pools that are related to energy metabolism (PPKs and ppGPP synthesis pathways for example) have a much stronger impact on growth. Or in summary, things are bloody complicated and heck do I have forgotten a lot.
  3. But again, the pools are regulated differently and it is not a simple unregulated conversion. One of the reasons is that the AMP-ATP ratio is important for intracellular energy regulation. GTP on the other hand is not part of the same circuit. Thus, it can be used without affecting aforementioned ratios. As already mentioned, in terms of energy content they can be seen as equivalent. Not in terms of physiological role, however.
  4. That is precisely my point. I was thinking about making storage options mandatory (though I am not sure how to enforce that). Number locks are probably a good option, but I have heard of cases where kids got hold of regular key locks and got the gun out to play with it...
  5. That sounds very reasonable to me. It may be implied but I would also add something like proper storage training or at least something that minimizes the risk of having kids get their fingers on guns. Fingerprint-coded storage perhaps?
  6. Relief medicine does not treat the infection. It mostly modulates symptoms by altering your immune response (the inflammatory pathways). Again, recovery within a week is more indicative of common cold than flu.
  7. I would advise caution from diagnoses such as these. Whatever may have happened should be discussed between OP and a medical professional. Blue sky speculations are at best detrimental.
  8. So you do not do an internal calibration. Chances are then that if other proteins are higher you have simply started with a higher total amount. I.e. there is some error in protein measurement. What you can do is assess the variance in your measurements taking all potential issues into account (e.g. due to calibration issues, instrument stability, reagent use, timing etc.) and see whether that covers the observed differences. All in all it really points to technical issues rather than biological effect.
  9. Background expression? You mean that your general protein amount is higher prior normalization? If so an artifact is the most likely culprit. Silent mutations can have regulatory effects, depending on locus, but I would first make sure that the values are properly normalized.
  10. Not necessarily I assume that both roughly hold roughly the same amount of energy for most intents and purposes. Usually the GTP is used as a energy source for different purposes than ATP. GTP pools are much lower though. In essence it depends on the context (e.g. total energy calculations?) whether it makes sense to treat them as one. Obviously, the cell does not.
  11. They are great apes (like us), not monkeys.
  12. And missing the obvious part that the current Government in Turkey is mildly Islamic (AFAIK).
  13. No, you are thinking of fermentation. While it is a means to regenerate NAD, it is not always done during anaerobic respiration. Obviously different bacteria utilize different electron acceptors including nitrate, fumarate, metals (Fe, Cr, U to name a few) and much more. The key is that the redox potential betwen NADH and the potential acceptor is sufficient to power proton extrusion. However, in a MFC this point is moot as the electrode is acting as the acceptor (otherwise there would be no electricity). As electron donors quite a lot of sources can be used, which are shuffled into the TCA cycle. However, many anaerobic bacteria are adapted to utilize small C bodies such as acetate and propionate as occur more frequently where they live (such as deep in soil).
  14. This statement also betrays quite a state of ignorance on that matter. There has been a tradition of secularism in Islam (see Ira Lapidus: A history of Islamic societies), dating back to the 10th century. There have been conflicts between secular (state) and religious entities, but both were somewhat more intermeshed (IIRC) than their Christian equivalents as they were not as rigidly and hierarchically organized. In modern Times Turkey is the most obvious example for a mostly secular Islamic state. Interestingly the secular wing is considered more authoritarian, whereas the Islamic faction tends to be more liberal and seeks to reform Islam e.g. to reduce misogyny http://www.theguardian.com/world/2008/feb/27/turkey.islam. This pretty much refutes the premise given in the quote. One issue is that in many countries the modernization was conducted within a much shorter period of time as compared to many Western countries. Oftentimes secularism was connected to authoritarian Dictatorships which bolstered religious counter-movement. In short things are embedded in historical settings in highly complicated ways and blanket statements (or even worse, projections based on these) are almost inevitably wrong.
  15. To add to the insurance part, higher genetic diversities protects from diseases as some may be more resistant against them. However if every plant is genetically the same, then if e.g. a virus can infect one plant, all plants are in danger.
  16. The thing you want to look into is power analysis.
  17. The beginning of the post is kind of correct, although the gene in question is not really a cultural one. Variations of DRD4 alleles have been associated with novelty seeking, but also of ADHD. The precise mechanisms remain speculative. The next paragraph pretty much breaks down especially with reference to European pioneers in North America. In order to understand the patterns much longer time spans have to be taken into account. A study by Chen et al (Evolution and Human Behavior Volume 20, Issue 5, September 1999, Pages 309–324) has shown that prevalence of a long allele variation is indeed associated with migration, but over much longer distances and timescales. For instance, the highest prevalence is found in the Americas, but from populations that came from Asia (e.g. Ticuana, Karitiana, Quechuan, Cheyenne). The average frequencies of North Americans (just to avoid confusion, of course natives Americans are meant here) is about 32% for the long alleles, in South America 69%. There is the usually caveat with how populations are assigned etc. but as a whole there appears indeed to be a correlation between the long variant frequency and migratory patterns of certain populations. Note that this does not indicate a gene for a given culture as all humans have that gene. It is just that certain allele frequencies are more common than in other population. Conversely it means that if someone has a certain allele one cannot assign the individual with certainty to a given population. Europeans had a lower frequency (around 20ish) but there was no significant difference between populations emigrated to the US and those in their original countries. This was taken as evideence that the pattern did not emerge from founder effects but rather due to selection (I have no idea what self-selection is means in this context). I.e. in populations where a sedentary lifestyle is more beneficial e.g. by developing strategies to utilize limited resources novelty-seeking could be selected against (as being too wasteful), whereas the opposite may be the case in populations that rely on exploration and migration (which may include nomadic lifestyles) the opposite may be the case. But again, the time frame we are talking about are in the order of millenia. Relatively modern emigration does not really factor in. Especially considering that the selective forces are/were quite different ten thousand years ago that would have shaped the DRD4 frequencies.
  18. I am not sure about that, but I remember vaguely that at least for mice being subjected to starvation periods increased metabolic pathways that lead to increased storage of fat. It is obviously a combination of many factors. Without sufficient food intake obesity is impossible. However there are variations in the utilization of food depending on genetic but also metabolic factors. One should keep in mind that metabolism is not a completely homeostatic system as it is sometimes depicted at. It changes due to internal (e..g age, stress, activity) as well as external cues. As such it will be very difficult to get a decent predictive model of everything that ultimately leads to obesity.
  19. The only thing one would need to take into account is the rate of permeability and how much it differs from free diffusion.
  20. Why would you think that is the case? More precisely what is the mechanism of nutrient transport through the phloem, what determines direction? (Hint: check mass flow hypothesis).
  21. Oftentimes wealth and higher level of education go hand in hand. But yes, that is an excellent point
  22. Also one should note that it is not necessarily religion that causes the issues, though it is a convenient rallying point for extremists to push radical agendas. The more important thing to look at is stability of a region and wealth (as well as distribution thereof). And of course there is a huge bias in terms what we see in Western media. Just to pick an example, remember the Rwandan genocide in 1994 with nearly a million deaths? While it was an ethnic cleansing, the killings were sanctioned by parts of the church (Rwanda is about 93% Christian). Essentially they created a moral climate in which these killings were justified (Timothy Longman, Christianity and Genocide in Rwanda New York: Cambridge University Press, 2010) The same arguments are made for Islam and e.g. honor killings. In a similar note one could decry Christian influence in outlawing homosexuality. Bottom line is that religiosity can and is being abused to legitimize atrocities and no religion has a monopoly on it. Their overall policy change over time but it always depends on who the persons in power are and what they agendas may be. Something that media like to tell us is that it is the others who do the atrocities. What history (and psychology and sociology) has taught us is that it is everyone of us, given the right (or wrong) circumstances and excuses.
  23. Depends on the details. Assuming that the chamber is filled with a liquid, the main issue is that oxygen may permeate the chamber. In that case the bacteria would just utilize the oxygen instead of transferring to the anode. Also the medium most be low or devoid of alternative electron acceptors, or again have means to limit bacterial access to them. However, if there is a rich community in that thing and something that limits diffusion (e.g. densely packed particles and/or a slurry) it should work. If a liquid medium is used I some kind of membrane is required to separate the electrodes (to limit diffusion).
  24. There is a good chance that much of it would have been slightly misrepresented, anyway. There has been a slow but continuous shift in perspective with regards to teaching of the material in the last decades. I know that I teach things quite differently now as compared to what I learned as a student. Edit: What I meant is don't feel bad about it in Bio everyone is wrong. Just some less than others....
  25. Nitpick: GTP itself is a source of energy (the energy is in the phosphate bonds) during translation, for example. Also, cellular respiration is the means to gain energy rather than to utilize it. More precisely, respiration generally refers to the electron transfer reaction resulting in the proton motive force required for the ATP synthase. To avoid (promote?) confusion I should add that most textbooks also include catabolic pathways that deliver reduction equivalents to the electron chain, which IMO is too broad for many purposes.
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