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Everything posted by Stefan-CoA
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0.000370114 / 299.792.458 = 0.000001234
Stefan-CoA replied to timeoftimezero's topic in Speculations
C squared isn't 299.792.458 that's just simply c, also where are you getting all those other numbers from? Or are you simply reverse engineering them from your special number? -
Alternative for natural selection
Stefan-CoA replied to pwagen's topic in Evolution, Morphology and Exobiology
Haha, that is so true. The limits of our knowledge at this point in time are impressive, yet the rate at which these limits are being pushed back is equally as astounding. We have in our department a group of scientists that have dedicated the last 30 years to a single enzyme and still they aren't quite sure exactly how it works/is regulated etc etc. I fear the day though when people start looking at the relationship between quantum mechanics and biological systems o_0 -
Is the U S shirking it’s duty to democracy ?
Stefan-CoA replied to Greatest I am's topic in Politics
I don't know what the best system would be. Maybe a type of benevolent/voluntary dictatorship? A temporary system wherein people's freedoms are somewhat restricted for x amount of time until the country reaches y set of criteria at which point the system is slowly abolished in search of a better one? I admit I may have a bias here because democracy isn't all it's cracked up to be in my country where the guy with the strongest tribal ties ends up winning. I just think that some countries should possibly be allowed to come to democracy on their own at their own pace rather than forcing it upon them by way of smart-bomb and assault rifle. -
Is the U S shirking it’s duty to democracy ?
Stefan-CoA replied to Greatest I am's topic in Politics
America is not the world police. This illusion that democracy is the greatest system out there along with the US being the greatest and only country able to enforce democracy through violence is quite damaging. In rich, well-fed and developed countries democracy may work, yet in the poorer countries I'm not so sure that it's the best system just yet. What about the people in Africa? Also, if the revolutionary forces are too weak to do anything by themselves, well then hasn't their revolution failed? Because all they end up saying is "Yeah! We beat the government, but only by calling on the greatest military might the world has known". It's like beating the class bully by calling your big-brother who's a champion boxer to do the job. -
Check out pubmed, webofscience, sciencedirect or even nature.com, depending on what access your institution offers. At what level are we talking about here?
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Wiki them? Carriers come in different forms (active, passive etc) and membrane pumps only in one. If you "pump" something, you require energy to move something from low to high. I hope that helps a bit.
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If you do not have the passion for science then there was no point in you pursuing a science degree. Rather speak to your professor on this topic as I'm sure the job opportunities vary from country to country. The safest would be to continue your studies for another year or two (masters degree) and then seek a job in research. With just a basic bsc I wouldn't recommend going into any sort of counselling as you are still too inexperienced to offer proper advice. Also counselling isn't about "killing infants" to suggest so is absurd and insulting. When counselling the best thing you can do is make the parents aware of everything that they'll be facing IF the baby is born with a disease, what they do with the information is beyond your control. Forensics, as you have guessed is more or less procedure work, but it's stable as good forensic scientists are always needed and it would bring to bear a certain satisfaction knowing that you're helping condemn murderers and rapists wouldn't it?
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Alternative for natural selection
Stefan-CoA replied to pwagen's topic in Evolution, Morphology and Exobiology
Be very careful when people make statements like this, as it is most likely not true. In the first instance you are dealing with a (relatively) simple occurrence, size and colour of a tail. In the second, you are dealing with how the size and colour (separately) affect the female; i.e. The effect from the point where the signal enters they eye all the way through to the brain. Next you are dealing with the genes that regulate the awareness of the environment and stress factors; food, predation levels, temperature etc etc. Then your female will most likely have to be in heat as well, so you've got genes regulating that. Then you've probably got genes regulating behaviour that's along the lines of "Well if this tail is that big, shouldn't I wait and see if a bigger tail comes along?" as well as those that regulate "This tail is too small, that tail is too big, this tail is just right for me". I'm just hypothesizing, so take what I say with a pinch of salt If that is indeed what Dawkins said, then as a Biologist I find that rather insulting. Biology is incredibly complex, you have intricate metabolic webs that regulate and self-regulate each other, highly complex biological codes that determine who, what and how you are. You don't just have the genome anymore, you have proteomes, metabolomes, and expressomes. Not only is it the information stored within your genetic code that determines what's happening, but the information in your proteins, in your enzymes even in the levels of certain metabolites in certain areas at certain times, and all of these fold back on each other and form this web of interactive regulation that is beyond our wildest dreams. And that's just if you're E.coli. If you go on towards higher forms of life, humans even, you have the brain to worry about, the nervous system, circulation, digestion; all of these coming together as one to perform the myriad of processes that allow you to think, to feel, to live and breathe. And all of this is just the tip of the iceberg, there is wonder within ourselves that is beyond our wildest imaginings. And of course, we can also trace this back to astrophysics. The elements that make up our bodies are born in the furnaces that are stars and are slung cosmic distances to settle here on earth. As Carl Sagan said "We are made of stardust". Some of the techniques that are used to analyse the world without, are also used to analyse the world within, spectrophotometry for example, radio-frequency analysis and I'm certain one or two more. How people can not see the beauty of science, the marriage of the seemingly impossible with the possible through thought and experiment is beyond me. -
Can HIV pass through condoms?
Stefan-CoA replied to John Salerno's topic in Microbiology and Immunology
As far as I know the biggest problem with condoms (w.r.t. Preventing HIV or pregnancy) is breakage or slippage. But even so, even IF there were a error-rate (say 1/20) that seminal fluid could be transmitted, barring abstinence, condoms would still be the most effective way of preventing HIV. But condoms do NOT promote the spread of HIV, the do NOT increase the risk of pregnancy or any of these things which the Catholic church has so wonderfully lied about. The pope came to Africa a few years ago (specifically sub-saharan Africa) and actually counselled against condom use! In an area where you have over 20 million HIV sufferers, that is just blatantly immoral. -
Most certainly I think, otherwise all the SplinterCell video games have taught me wrong! No, but I'm fairly certain that since sound is a wave and light is a wave (sometimes) the two should be able to interact somehow.
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Alternative for natural selection
Stefan-CoA replied to pwagen's topic in Evolution, Morphology and Exobiology
Yup you can say that, they actually performed a series of analysis on one or other bird of paradise and found that exact correlation, but only up to a point. The larger the bird's tail the more likely it was to get tail, but only up to a point, after which it was too heavy to fly and would get eaten by ground-based predators. -
Hmmm, on what level are we talking here? University/College or High School? Hand rails in general won't have all too many bacteria on them, since they are mainly metal and most bacteria won't survive on a metal substrate (especially in an aerobic environment). You could try to identify which viruses are present on the hand-rails and how to defend against those? Or maybe something about the communicability of diseases in high-density urban areas? The resistance thing is a good start, but I don't know how successful you'll be as most soaps use a detergent, which already destroys cell membranes and as far as I know there isn't any resistance to that. OH! Maybe you could perform a series of directed evolution experiments to determine IF resistance to detergents would be possible? Or how to incorporate the mechanism of action of detergents into substances that are safe for human consumption?
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By "read" chemistry do you mean the structures? I found that there are two helpful sites in this case, wikipedia (just search for what you're struggling with) or chem-wiki (simply google it) which even teaches you reaction mechanisms. As a rule it's good to know the OCTET rule and VSEPR theory.
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One of the side-effects of too much caffeine is nausea, so maybe that "hollow" feeling you're getting isn't hunger but nausea? I get that sometimes after my 6th cup or so that there's this empty feeling that equates to hunger, but when I eat it just gets worse. So, it could possibly be that you're just genetically predisposed to experiencing the effects of caffeine at lower doses? Is it just nausea or do you get jittery/hyper or more alert as well? Any other symptoms?
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Do you get hungry immediately or a short while thereafter? Caffeine revs up the body's metabolism, so it would make sense for you to get hungrier as time goes on. Coke also has a high sugar content which may over stimulate the insulin/glycogen system leading to a "sugar crash" (speculation).
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Those are the risks with any form of knowledge. It's up to us as scientists to provide correct interpretations of this knowledge, or at the very least make it accessible to the layperson. But just because something is scary doesn't mean one should abandon it (point in case my ex-girlfriend ). Maybe just more prudence would be advisable. Oh and we've technically already created new species. Check out J.Craig Venter's work, and before that there's a Plasmodium I think that was stripped of all but the most essential genes. I can't remember it's name though, sorry.
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Alternative for natural selection
Stefan-CoA replied to pwagen's topic in Evolution, Morphology and Exobiology
Your last sentence doesn't make much sense (to me at least) would you mind clarifying? As I understand it, HGT, Immigration, gene flow, mutation etc are all part of processes that generate variation, which is then acted upon by natural selection. Natural selection by itself does not generate diversity, it merely sorts out what it can and can't use. The principles are the same as for artificial selection (eg. using antibiotic resistance genes to probe for transformed bacteria) it's not the selection that brought about the change, it merely brought it to the fore. That's how I interpret it anyways Intelligent Design can be seen anywhere you wish. Humans will always try to make sense of patterns they don't fully understand, which is why ID has so many adherents. It's easy to see design everywhere. -
Alternative for natural selection
Stefan-CoA replied to pwagen's topic in Evolution, Morphology and Exobiology
How I see it is rather simple I think. You have your various sources of variation (drift, mutation, etc) which all serve to generate diversity. Now at any one point, x amount of these will be beneficial to the organism in the current environment. Natural selection acts as a type of sieve that uses the environment to filter out what may or may not survive. This is where the concept of fitness comes in, the organisms that are most suited to the environment (most adapted) will have a higher probability of reproducing. That isn't to say that they will, but that if given the opportunity there's a greater chance of them producing offspring than a "less-fit" organism. -
That's what the various genome projects are all about. To determine the sequence and meaning of the various nucleotide combinations. Apart from the obvious academic importance, this knowledge would allow us to a)exploit this knowledge to our benefit, b)cure/prevent diseases, c)improve crop viability/sustainability, d)discover novel substances which could find a variety of applications. The possibilities are quite endless.
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Yeah, the optimum conditions for any enzyme (temp, pH, ion concentration) are usually the one's where the enzyme works best without being denatured. There are exceptions, like some enzymes would work better at a higher temperature, but not for a long time, or if they're in biological systems without damaging the host. As a rule of thumb though, you can say that if an enzyme has an optimum pH of 7, it'll work better than if it were at a pH of 6 or 8
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The more active an enzyme, the faster it's reaction rate will be. That about sums it up I guess. It also depends on things like cooperative binding and inhibition/activation (as in agonist/antagonist) and also on the type of reaction. Certain enzymes perform really slow reactions (but which would none-the-less take a few thousand years to complete) whereas others can react several times a minute. But the essence is this, activity is proportional to rate.
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I also think that the washing powder (if you used any) would have neutralised any ill-effects that may or may not have come to be. But yeah, 5% vinegar diluted by a wash cycle of about 12 liters, as well as a low concentration of bleach isn't going to do much. Even is you did miraculously end up creating chlorine gas, the amount would have been so little as to be negligible. EDIT: Ah crap, it's late and I didn't read the earlier posts. I just repeated CaptainPanic's words. Sorry
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No, what it means is that thiols are more likely to donate their proton (forming thiolate I think). Thiols have a relatively high pka (for cysteine it's about 8.37) which means at pH higher than that, the thiol will donate it's proton, acting like an acid according to the Lowry Bronstedt model. Hope this helps