Uh, I'm checking notes from my Bacterial Pathogenesis lectures, and they say that YOU'RE wrong. The University of Southern Carolina med school site also has a page of notes on this matter that agrees with what I've learned; this isn't based soley on the TED talk, this is based on what I've learned from prior experience in bacterial pathology.
"Antibiotics are categorized as bactericidal if they kill the susceptible bacteria or bacteriostatic if they reversibly inhibit the growth of bacteria. In general the use of bactericidal antibiotics is preferred but many factors may dictate the use of a bacteriostatic antibiotic. When a bacteriostatic antibiotic is used the duration of therapy must be sufficient to allow cellular and humoral defense mechanisms to eradicate the bacteria."
Or am I misunderstanding something? Are you a biologist of some sort with experience in the field?
I doubt he invented the concept. In the afterward sections of his books, he often talks about how he draws from other sources. I'm pretty sure in one of his books he mentions how he consulted medical workers on plausible scenarios; Card could've simply picked up the idea of communicating via chemicals through such an experience. While the earliest scientific article I can find on quorum sensing, through PubMed and Web of Science, is from 1995, I'm sure the idea of microorganisms communicating through such a mechanism is much older and probably predates Xenocide.
The method of anti-bacterial action you say she presents is precisely how bacteriostatic antibiotics work, by inhibiting growth of bacterial populations; the point is to give your immune system a chance to catch up with the bugs, making them more manageable. In that sense, it's not a stretch that drugs that imitate quorum sensing signals could replace antibiotics. At the very least, more drug options would be provided. This would be important when the bugs become resistant to our existing drugs.
You are correct to say that IF we cannot provide hypotheses explaining how these proteins managed to aggregate and form the structure of a flagella we cannot prove evolution.
But, if one argues that our current state of knowledge provides no explanation for the evolution of the flagella, I would say they lack imagination.
Here's a hypothesis:
If the flagella began as a protein export mechanism, it could have evolved into the Type III secretion system and then into a flagella.
Further speculation: The motor of this proposed protein export mechanism could have started out as a simple pore complex geared towards protein export. Mutations cause some of these exported proteins to adhere to extracellular portions of this export mechanism, forming the tube like structure of the Type III needle. Over time, mutations alter the structure slightly, without harming the function of this apparatus in protein export, causing it to resemble flagella more and more. Without selection pressure against these developments, these changes persist. In fact, genetic drift may cause these changes to become fixed in a population. Gradually, even more changes occur contributing to the drive motor, resulting in the flagella you see today.
Granted, all of the above is merely a story, but that's not to say that it isn't true. I don't think this scenario is that far fetched, and further study of the flagella may even validate it.
At this point I'd like to point out that it could be interesting to look at research into the specific events occurring during flagella assembly; if you think about it, the flagella IS assembled piece by piece. One would think that flagella intermediates would resemble intermediates in flagella evolution. By studying these "assembly line intermediates", function could possibly be derived (my old biology teacher's mantra: form gives function), further answering the question of flagella development.
Any input on spontaneous polymerization of nucleic acids? I believe the current theory is that RNA was the original genetic code, which was then supplanted by DNA; but, RNA was also the original cellular machinery, then supplanted by proteins through evolution.
It could be that nucleic acids came first, eventually creating the conditions under which organisms synthesize polypeptides today.
Thanks for the information, btw. I was never that great in organic chem:)
Well, proteins are simply chains of amino acids. It's really cool if you think about it; amino acids have amino and carboxy terminuses. The carbon in between these 2 are hooked up to a variable side chain with varying chemical structure/properties depending on the amino acid.
But, moving along, the carboxy and amino terminuses are perfectly capable of linking up via chemical reactions. It wouldn't be a stretch, taking into account the conditions of ancient Earth, that amino acids in the "primordial soup" just kept linking up and polymerized under favorable conditions, generating complex proteins.
Personally, this is why the evolution of early life is so interesting to me. The modular structure of DNA, RNA, and proteins, coupled with phospholipids (which spontaneously form cell like compartments in water), if all these are thrown into early earth conditions, spontaneous creation of life seems very, very possible.
I think "Why asteroids?" could be answered by the fact that there aren't any neutron stars sufficiently close to Earth; this is a good thing.Pulsar variants of neutron stars are actually destructive in the sense that they spew high energy radiation (including gamma radiation, 'cept we don't Hulk out if hit, rather we... well bad things happen) from their poles. Certain neutron stars also become black holes (which apparently also spew out high energy cosmic radiation). I'm guessing the consequence of this is that Earth is nowhere within "firing range" of a neutron star. Great for us, as the planet would've been exposed to so much cosmic radiation that life would never have gotten started.
Asteroids, on the other hand, can travel through the cosmos and be exposed to these neutron stars. Eventually they end up in a solar system and can seed planets with organic material such as amino acids. Furthermore, distance shouldn't be a problem for amino acid exposure to polarized light; as long as nothing is in the path of an electromagnetic wave (such as light), the wave should propagate infinitely (I'm no physicist, so take this with a grain of salt).
The main problem with the argument made in the article is probably the statistical improbability of an extra solar object carrying the L amino acids wandering into our solar system.
Meh. I don't enough about asteroids wandering inter-solar expanses or neutron stars and the state of the galaxy ~4-5 billion years ago. Unless I decide to study some more astronomy, I probably couldn't say much more about this topic. It's too bad; not enough hours in a day and not enough time in our lives to master enough subjects to gain a good understanding of things. Not even multiple subjects, just ONE.
But I agree with your final assessment; the article seems to be making wild assumptions (or seems to be because we don't know the subject well enough). Right handed, btw =P Being left handed would be cool though. I'd have an advantage in some sports:D
I'm not sure if the ocean would filter cosmic rays that well; light does penetrate to a certain degree (higher energy wavelengths, blue, for example), and UV certainly does penetrate (much higher energy than blue light), illustrated by swimmers getting sunburned while underwater. Second, I don't think any of the gases comprising the early Earth atmosphere have the unique UV absorbing property O2 and ozone have.
I think you missed my point, though (Apologies, I probably wasn't very clear); I'm pretty sure radiation is necessary for the formation of organic molecules such as amino acids. Even if a chemical reaction is favorable, the length of time required for it to complete could be unreasonably long. I mentioned early Earth without it's ozone shield because it illustrated the conditions under which organic molecules could form; cosmic radiation is present to provide the catalytic energy required for quick organic synthesis. This is why I don't believe amino acid formation on an asteroid is farfetched; while conditions there aren't exactly the same as those on early earth, they should be similar (provided ingredients for organic molecules are in place), and asteroids have the added advantage of being in space, where radiation to provide energy for chemical reactions is ample.
But, I guess your quarrel with that theory is that the amino acids would be damaged by cosmic rays? That is something to consider, as after amino acids formed on ancient earth there were likely tangible objects to shield them from destructive radiation. But, I imagine accumulation of a dust coating on the asteroid/meteor, or perhaps forming in a crevice could provide ample protection? Interesting topic.
Earth didn't have any oxygen in the atmosphere until several billion years ago (approximately). This meant no ozone and excessive radiation hammering primordial Earth, providing energy necessary for chemical reactions that could generate organic matter necessary for life.
There's also been evidence suggesting that the Earth suffered a catastrophic collision with a Mars sized object (this resulted in the formation of the moon); if organic molecules had already been created prior to this event, and the collision sent pieces of Earth with , say, amino acids, out into space, could this account for the celestial objects carrying left handed amino acids?
No.
Is this science or fantasy? Am I to believe that amino acids somehow formed on an asteroid (magic must happen) I doubt that there's anything indicating that you're to believe that amino acids magically came into existence on an asteroid. I do think you're to assume that free floating atomic elements in space underwent chemical reactions forming amino acids when exposed to radiation. Couple this with the formation of a solar system and subsequent condensation of interstellar dust into planetoids and other objects, you end up with asteroids with amino acids on them.
then, within the vastness of space, managed to soar passed some neutron stars without getting sucked in, Shit happens. I'd tell you to ask the dinosaurs, but... oh yeah. Shit happened. And not all neutron stars are black holes that suck things in. FURTHERMORE, pulsars are special types of neutron stars beaming radiation. This radiation traverses great distances and can feasibly nuke an asteroid, light years away, with radiation. I believe there was a "Death Star" article recently about such a pulsar, notable because the Earth was within range of it's radiation blasts.
and then, found its way to Earth, survived entry into the atmosphere and produced life? Are you assuming that there are living things on this meteorite? And notice, I specifically say "meteorite", the term for an object originating in space that has survived reentry and impacted the earth's surface. Living things surviving reentry on an asteroid might be sketchy, but complex molecules are another story.
To be honest, I don't understand your incredulous attitude. Putting together what I know from astronomy and my biology background, what's suggested in the article seems very feasible. I'd think anyone who took high school seriously would be able to come up with the same conclusion.
No problem. I guess the whole thing can be rather tricky. The KMT was the governing party of China when WWII ended and the UN was founded, but when the Communists came to power, the KMT really had no control over anything outside of Taiwan. I think 30 years ago this reality became apparent (there was no way China was a part of Taiwan) and the situation evolved to where it is now, where Taiwan is essentially a nation in every way but in name and officially a Chinese province. To your original point, only those original KMT members who followed Chiang from China (and perhaps their descendants) would likely regard China a part of Taiwan.
Anyhow, regardless of whatever formal stances that exist, the reality of matters can be far different; consequently, the truths about things are harder to discover.
If Chiang Kai-Shek was still alive, your statement would be correct. But he isn't. I don't know of any Taiwanese who would argue China is apart of Taiwan; those people must either be extremely elderly or dying. In truth, ~40% of Taiwanese would argue Taiwan is it's own nation, while the other 60% would be arguing that the Taiwanese should keep their yaps shut so China doesn't invade and ruin their day. (I'm basing the numbers off recent election results)
I think you're talking about the PRoC instituting proper industry controls, not the ROC. The difference? The former is China proper (mainland China, communist China) and the latter is Taiwan. While it's obvious China has some issues, made evident by the diethylene glycol laden toothpaste scandal, I'm pretty sure Taiwan has had systems in place for a while now to ensure something doesn't happen to their exported products. http://taiwanreview.nat.gov.tw/site/Tr/fp.asp?xItem=311&CtNode=128
The article I just linked shows evidence that Taiwan became aware of consumer confidence in goods in the late 80's, right around the time when it began a move toward formal democracy, and began addressing the issue with the emplacement of quality control measures.
The only problem I see in Taiwan, and this is going to be true in China and other Asian countries as well, is quality control of street vendor goods. In these situations, the vendor could be a small farmer who slaughters his own farm animals and sells them directly to consumers, bypassing whatever quality control measures the government would have in place. Of course, these things wouldn't be exported, and aren't as much of a concern to the rest of the world.
Well, first off, nowhere did I say that the US is perfect and is now incapable of making mistakes; I'm pretty sure no national government is immune to missteps. I just wanted to point out that missteps that have been made really shouldn't be repeated.
As to your complaint about the parent being modded down; he's been modded +1 interesting at this point. You should probably keep in mind that/. readers do the moderating here, and/. readers, like national governments, are not infallible. Next time, it might be a better idea to more clearly point out that there was no reason to mod the parent down, and, if anything, the parent should be moderated up for interesting points.
Just because the poster might be American doesn't necessarily mean he bears some blame for the decimation of the Native American population in the US; how could you justify your comment (that you hope he isn't an American or US military supporter) if the poster is a 2nd generation descendant of an immigrant family?
Regardless, there's a point that you missed. The US obviously made mistakes in the past, and China looks like it's going to follow in the US' footsteps. Its treatment of Tibetans could be viewed analogous to US treatment of Native Americans during US westward expansion. While it is China's sovereign right to make itself a strong nation, I would hope it does so in a manner where it looks at mistakes made by other nations and avoids those pitfalls. So far, it's been failing. Case in point, diethylene glycol tainted toothpaste. To me, this seems to be a mirror of the snake oil salesmen from industrializing America, prior to governmental regulation of goods; it prompts the question, "Someone's made these mistakes before; why are you so intent on following in their footsteps?"
You're not taking into consideration the smoke coming from the burning tip of a cigarette. That stuff is unfiltered, undiluted, and research shows that carcinogens in this smoke are found at higher concentrations than in smoke being exhaled.http://www.ncbi.nlm.nih.gov/pubmed/16319363
Regardless, second hand smoke is certainly something I don't appreciate having to endure when I end up trailing or walking next to a smoker traveling in the same direction.
This is nowhere near designer baby capabilities that were prominently featured in GATTACA. This is simply the swapping out of somatic nuclear/genetic material from one cell to the other, taking advantage of the fact that mitochondrial lineages propogate clonally. This isn't a genetic disease in the sense that you're thinking; it's not a disease found in the human genome. It's a disease isolated to the genome of one of our organelles ("organs" for our cells).
Quick bio recap: I don't know if you remember much from high school biology, but there are 2 sources of DNA in our cells, mitochondria and nucleus. The experiment in the article is essentially swapping mitochondria between 2 people, allowing someone to live without a potentially life threatening mitochondrial defect. In other words, once the mitochondria have been swapped (or in this case, genomic DNA), the person SHOULD develop as he would if he had normal mitochondria in the first place. The only reason I say SHOULD is because we don't know how the RNA content of the genome receiving cell will affect development (as opposed to maternal RNA in the donor cell). But, the person's genetic make up would be the same in both scenarios. I cannot emphasize enough that there is no specificity in what genes are transferred; you cannot pick and choose what gene gets moved, and from what I know, I don't think you ever CAN. You're moving a whole GENOME here.
Now, unless different mitochondrial lineages can affect ATP production to fuel bodily/cellular processes, conferring an advantage somehow by having more efficient ATP production or what not, this type of treatment isn't going to generate the same class divisions and prejudices you saw in GATTACA. Lastly, the kid who results from this treatment wouldn't be a mutant; mutations are changes in DNA sequence, structure that prevent proper transcription and translation into protein. These would be examples of genetic diseases, which you mentioned earlier. To further elaborate, cancerous cells could be considered mutants because of a defect in it's DNA sequence, but a person who has cancer isn't a mutant; only a subset of that person's cells, the cancerous ones, are mutant.
Hrm. This is OT, but you wouldn't happen to be mrxak from AmbrosiaSW forums and Aftermath, would you?
Re:Extremely good and painfully boring at same tim
on
Cloverfield Discussion
·
· Score: 1
The beginning was slow, but I'd argue the that the goal of the plot is only feasible if this first part occurred. Whoever followed your suggestion might be asking, "Why did Character A do this, and what's the significance behind Character A and B's relationship at the end of the movie?" I could imagine people asking, "What's the freakin' plot? Did it have one?!!!111!1" If they skipped the first part. And well, they've started asking this even after seeing the whole thing.
For those out there who are now worried; yes, it had a plot. My opinion of those who didn't discover the plot are that they are dumber than a box of rocks, which is entirely feasible. When a metal plate with 5 nubs arranged in a linear fashion appears on screen, and the response from one audience member is, "5 nipples? WTF? I don't get it", you begin to question the intelligence of some fellow moviegoers.
Ok, now, back to the original topic: I like stories, and perhaps it's because I get attached to characters easily; therefore, as long as SOME character development is present, I'll be able to relate/care for them in some way. What development in this movie was enough for me, and it certainly wouldn't've been the same for me if I skipped the beginning. The last 2 lines of the movie wouldn't have the same impact if I hadn't seen the beginning. In other words, don't skip it. Besides, even if the first 20 minutes is boring for you, I'm sure the other hour would more than make up for it.
Interesting point, which I admit I neglected in my post. This does prompt me to wonder if animal mitochondria could be removed from animal cells and be replaced with mitochondria from the human cell.
I find this incredibly irritating. The specifics of the term "hybrid" are not elaborated upon and the continual use of the term"human-animal hybrid" allows for people to develop the notion that scientists out there are actually creating some monster chimeric creature.
Not. True. If you click on "Q&A Hybrid Embryos", found in the right hand nav bar, you'll see what I mean. I've provided the link below:
This second link elaborates on why these eggs are considered "hybrid". Genetic material (DNA) is essentially removed from animal cells, leaving an empty nucleus and functional cellular machinery. In other words, you have a cell without DNA that looks very much like a human cell without it's DNA. The scientists then inject human DNA into the animal cell's nucleus; at this point the animal cell reads instructions off the DNA and carries them out. The end product is essentially A HUMAN CELL, but with left over proteins and cellular material generated from the old animal DNA.
This is FAR different from what people appear to be assuming. It's not going to generate some half cow-half human monster/creature, and does NOT "blur" the boundaries between humans and other species.
I won't question your beliefs, but I must say that I'd have other explanations for situations where I was able to succeed when failure appeared inevitable. I'd usually attribute it to last minute quick thinking, thorough analysis of mistakes, help from others, etc. Now whether these things that helped me succeed where I should have failed were an act of God, I don't know. Currently, I believe everything that happens is the result of some causative event resulting in some sort of effect. If I were to make observations supporting that God had a hand in saving my ass, repeatable and verifiable by others, I'd gladly start believing in him.
I think that's the key difference between you and I. You say believing is seeing, that enough things happened to you that you started believing, and it changed the way you see things. I, on the other hand, need to SEE (DNA and things too small exempt; we have ways of allowing us to see results. Same with quantum physics and other sciences; we must see results to verify). If I see something unexplainable happen (Ok, if someone makes a car magically vanish in my living room while I'm sitting in it, science goes out the window. I don't think it'll happen though), I will never attribute it to the supernatural, I'll attribute it to something I don't know. With regards to evolution, I didn't KNOW the genetic and biochemical basis that lent support to it, but I assumed that there was an explanation for it. Once I became familiar with chemistry, biochemistry, how DNA, RNA, and proteins functioned, how they were modular and could be assembled in many ways, how genes could be reassembled to produce new genes with new functions through protein machinery, things that scientific methods could allow me to see, it only lent support to my belief that evolutionary theory was valid.
Hopefully you can see that I'm comparing my growing belief in evolution's validity to your developing belief in God. I would like to stress that I'm not trying to change your point of view; though, if you want to understand why I believe so strongly in evolution's validity, I would encourage you to learn more about biochemistry, DNA, RNA, proteins, etc. (though I'm sure you're a busy man and have little time, but you seem very open minded, which I applaud).
Furthermore, I hope you can see my point; I actually think you already do. One needs to become familiar with both sides of the issue before arguing anything. It certainly irritates me to no end when people argue against evolution without some sort of scientific background in biology, chemistry, biochemistry, especially when I found it so vital to solidifying my support for evolutionary theory. Whatever "holes" I thought evolution had in high school (and they weren't really "holes", rather questions of "How does this work?") were answered in classes I had in college, by my experience in biology research labs. If you can look at all the supporting evidence and argue that evolution is not a valid theory, then I will listen to you, provided your rationale and logic are sound.
Unfortunately, I find it hard to say the same about religion. While I certainly need to be familiar with arguments for the existence of God, I'm not sure if I need to read the bible to be able to argue that there are no supporting observations (reproducible, verifiable, through tangible experiments, or observation of tangible things) that gods or a God exists. Surely I shouldn't misquote the bible to make my point; no one should misquote anything, everyone should get their facts straight if they intend to use them in argument. But when belief in God is only possible through a leap in faith, I cannot believe God did something when I believe that there is some alternative explanation grounded in the physical world. And this belief doesn't require any sort of "leap of faith", or blind trust, it just requires one to believe that there is a cause and effect that resulted in something to happen, the cause bound, restricted, and answers to the laws of the physical world.
Baloney. Complete and utter baloney. If you don't believe that the earth has limited resources and finite carrying capacity, get some common sense, read some Malthus, or take a look in a biology book. We might be fine for the nearby future, but an unsustainable earth appears to be an inevitability. The earth cannot, will not sustain human life forever. The birth of this planet only provided it with so many resources, and our unregulated consumption paints a very bleak future for us. The problem is further compounded by the fact that our consumption is not just unregulated, but also has the tendency to destroy other resources through unsustainable practices.
Furthermore, humanity should have hit carrying capacity already; were it not for the UNSUSTAINABLE breakthroughs brought by the Green Revolution in the 40's-60's, that brought us increased crop yields, we all would likely have experienced famine (in some shape or form) sometime in our lives. We currently face reaching a new carrying capacity with our ever increasing population. Now that many Green Revolution agricultural advances have been deemed unsustainable (environmentally unfriendly, rendering farmland useless), this future becomes exceedingly dire; we have yet to find a way to increase agricultural production that will compensate for our increased population and replace Green Revolution techniques.
In any case, you missed my points regarding observations supporting evolution.
The key is that I said, "observations that SUPPORT evolution", not "the observation OF evolution". And you make the assumption that I'm a God hating atheist (quoting you: "I was raised a God hating atheist TOO..."), which I am not. I'm quite open to the possibility of a god; all someone has to do is present me with observations that support that such a being exists.
Now, why do I believe that evolutionary theory is valid? The biochemistry behind life, specifically DNA to RNA to protein, the modularity of this system, and the outcomes that result from such modularity lend overwhelming support for evolution. While some try to liken this process to throwing parts of a car into a big bag, shaking it up, and having a car pop out (therefore, supposedly, disproving evolution), it's not so. Atoms are not car parts; from what I've learned about biochemistry, the very nature of atoms makes evolution very possible. Furthermore, while what I've learned does come from text, this text does come from experiments that have been verified by repeated and rigorous testing that produces the same results over and over.
So, what I'm trying to say here is that there are observations that SUPPORT the theory of evolution and lend it credibility. As a result, it is not necessary to actually SEE evolution to believe in it, so long as there are supporting observations.
Also, I want to address your accusation that science is funded by corporations. This certainly isn't always the case. Public universities are not funded by corporations (mostly government funded, though occasionally corporations will pitch in, though rarely), and a LOT of science is done at these public universities. These public universities, ie UC Berkeley, UCLA, etc., engage in scientific research to try better the lives of the public.
Also (and please excuse me, I'm jumping all over the place, trying to provide replies to your points as you have structured your response) to elaborate on WHY scientists can support something so confidently, I think I need to explain the scientific process, at least for biology:
1. Experiments are done 2. Results, methods, procedures, discussion are written 3. Items from #2 are incorporated into a paper that is published in a scientific journal by the researchers 4. Paper is read, experiments reproduced by other labs to verify veracity of findings 5. If discovery is groundbreaking enough, it is incorporated into text books.
The repetitions required to verify the veracity of scientific discoveries are what lead scientists to be very confident in their beliefs; you say you believe what you see rather than what you read, but in science, and science textbooks particularly, the text presents what is seen multiple times, in experiments reproduced by many DIFFERENT groups. In other words, we have faith in the abilities of our scientific peers, that they are competent people, that they have produced the same results supporting a theory. Of course this theory can be disproven, but until it is, repeated experiments giving such a theory validity will allow the theory to, well, be regarded as valid.
Lastly, I don't mean to sound patronizing in defining "theory" to you; the problem is scientific theory is not widely understood by many, particularly because "theory" in a scientific context does not have the same meaning as it does in everyday vocabulary. See: http://en.wikipedia.org/wiki/Theory
Whereas in common usage, theory is meant to describe an idea about how something possibly happened, the scientific context of the word implies that the idea about how something possibly happened has been validated by numerous observations supporting it; scientific theory is treated as "fact" until proven otherwise. Keep in mind, good scientists will never regard a theory as "fact", just as something we have V
Slashdot Mirror
Uh, I'm checking notes from my Bacterial Pathogenesis lectures, and they say that YOU'RE wrong. The University of Southern Carolina med school site also has a page of notes on this matter that agrees with what I've learned; this isn't based soley on the TED talk, this is based on what I've learned from prior experience in bacterial pathology.
http://pathmicro.med.sc.edu/mayer/antibiot.htm
"Antibiotics are categorized as bactericidal if they kill the susceptible bacteria or bacteriostatic if they reversibly inhibit the growth of bacteria. In general the use of bactericidal antibiotics is preferred but many factors may dictate the use of a bacteriostatic antibiotic. When a bacteriostatic antibiotic is used the duration of therapy must be sufficient to allow cellular and humoral defense mechanisms to eradicate the bacteria."
Or am I misunderstanding something? Are you a biologist of some sort with experience in the field?
I doubt he invented the concept. In the afterward sections of his books, he often talks about how he draws from other sources. I'm pretty sure in one of his books he mentions how he consulted medical workers on plausible scenarios; Card could've simply picked up the idea of communicating via chemicals through such an experience. While the earliest scientific article I can find on quorum sensing, through PubMed and Web of Science, is from 1995, I'm sure the idea of microorganisms communicating through such a mechanism is much older and probably predates Xenocide.
The method of anti-bacterial action you say she presents is precisely how bacteriostatic antibiotics work, by inhibiting growth of bacterial populations; the point is to give your immune system a chance to catch up with the bugs, making them more manageable. In that sense, it's not a stretch that drugs that imitate quorum sensing signals could replace antibiotics. At the very least, more drug options would be provided. This would be important when the bugs become resistant to our existing drugs.
You are correct to say that IF we cannot provide hypotheses explaining how these proteins managed to aggregate and form the structure of a flagella we cannot prove evolution.
But, if one argues that our current state of knowledge provides no explanation for the evolution of the flagella, I would say they lack imagination.
Here's a hypothesis:
If the flagella began as a protein export mechanism, it could have evolved into the Type III secretion system and then into a flagella.
Further speculation:
The motor of this proposed protein export mechanism could have started out as a simple pore complex geared towards protein export. Mutations cause some of these exported proteins to adhere to extracellular portions of this export mechanism, forming the tube like structure of the Type III needle. Over time, mutations alter the structure slightly, without harming the function of this apparatus in protein export, causing it to resemble flagella more and more. Without selection pressure against these developments, these changes persist. In fact, genetic drift may cause these changes to become fixed in a population. Gradually, even more changes occur contributing to the drive motor, resulting in the flagella you see today.
Granted, all of the above is merely a story, but that's not to say that it isn't true. I don't think this scenario is that far fetched, and further study of the flagella may even validate it.
At this point I'd like to point out that it could be interesting to look at research into the specific events occurring during flagella assembly; if you think about it, the flagella IS assembled piece by piece. One would think that flagella intermediates would resemble intermediates in flagella evolution. By studying these "assembly line intermediates", function could possibly be derived (my old biology teacher's mantra: form gives function), further answering the question of flagella development.
Any input on spontaneous polymerization of nucleic acids? I believe the current theory is that RNA was the original genetic code, which was then supplanted by DNA; but, RNA was also the original cellular machinery, then supplanted by proteins through evolution.
:)
It could be that nucleic acids came first, eventually creating the conditions under which organisms synthesize polypeptides today.
Thanks for the information, btw. I was never that great in organic chem
Well, proteins are simply chains of amino acids. It's really cool if you think about it; amino acids have amino and carboxy terminuses. The carbon in between these 2 are hooked up to a variable side chain with varying chemical structure/properties depending on the amino acid.
But, moving along, the carboxy and amino terminuses are perfectly capable of linking up via chemical reactions. It wouldn't be a stretch, taking into account the conditions of ancient Earth, that amino acids in the "primordial soup" just kept linking up and polymerized under favorable conditions, generating complex proteins.
Personally, this is why the evolution of early life is so interesting to me. The modular structure of DNA, RNA, and proteins, coupled with phospholipids (which spontaneously form cell like compartments in water), if all these are thrown into early earth conditions, spontaneous creation of life seems very, very possible.
I think "Why asteroids?" could be answered by the fact that there aren't any neutron stars sufficiently close to Earth; this is a good thing.Pulsar variants of neutron stars are actually destructive in the sense that they spew high energy radiation (including gamma radiation, 'cept we don't Hulk out if hit, rather we... well bad things happen) from their poles. Certain neutron stars also become black holes (which apparently also spew out high energy cosmic radiation). I'm guessing the consequence of this is that Earth is nowhere within "firing range" of a neutron star. Great for us, as the planet would've been exposed to so much cosmic radiation that life would never have gotten started.
:D
Asteroids, on the other hand, can travel through the cosmos and be exposed to these neutron stars. Eventually they end up in a solar system and can seed planets with organic material such as amino acids. Furthermore, distance shouldn't be a problem for amino acid exposure to polarized light; as long as nothing is in the path of an electromagnetic wave (such as light), the wave should propagate infinitely (I'm no physicist, so take this with a grain of salt).
The main problem with the argument made in the article is probably the statistical improbability of an extra solar object carrying the L amino acids wandering into our solar system.
Meh. I don't enough about asteroids wandering inter-solar expanses or neutron stars and the state of the galaxy ~4-5 billion years ago. Unless I decide to study some more astronomy, I probably couldn't say much more about this topic. It's too bad; not enough hours in a day and not enough time in our lives to master enough subjects to gain a good understanding of things. Not even multiple subjects, just ONE.
But I agree with your final assessment; the article seems to be making wild assumptions (or seems to be because we don't know the subject well enough). Right handed, btw =P Being left handed would be cool though. I'd have an advantage in some sports
I'm not sure if the ocean would filter cosmic rays that well; light does penetrate to a certain degree (higher energy wavelengths, blue, for example), and UV certainly does penetrate (much higher energy than blue light), illustrated by swimmers getting sunburned while underwater. Second, I don't think any of the gases comprising the early Earth atmosphere have the unique UV absorbing property O2 and ozone have.
I think you missed my point, though (Apologies, I probably wasn't very clear); I'm pretty sure radiation is necessary for the formation of organic molecules such as amino acids. Even if a chemical reaction is favorable, the length of time required for it to complete could be unreasonably long. I mentioned early Earth without it's ozone shield because it illustrated the conditions under which organic molecules could form; cosmic radiation is present to provide the catalytic energy required for quick organic synthesis. This is why I don't believe amino acid formation on an asteroid is farfetched; while conditions there aren't exactly the same as those on early earth, they should be similar (provided ingredients for organic molecules are in place), and asteroids have the added advantage of being in space, where radiation to provide energy for chemical reactions is ample.
But, I guess your quarrel with that theory is that the amino acids would be damaged by cosmic rays? That is something to consider, as after amino acids formed on ancient earth there were likely tangible objects to shield them from destructive radiation. But, I imagine accumulation of a dust coating on the asteroid/meteor, or perhaps forming in a crevice could provide ample protection? Interesting topic.
That's an interesting thought.
Earth didn't have any oxygen in the atmosphere until several billion years ago (approximately). This meant no ozone and excessive radiation hammering primordial Earth, providing energy necessary for chemical reactions that could generate organic matter necessary for life.
There's also been evidence suggesting that the Earth suffered a catastrophic collision with a Mars sized object (this resulted in the formation of the moon); if organic molecules had already been created prior to this event, and the collision sent pieces of Earth with , say, amino acids, out into space, could this account for the celestial objects carrying left handed amino acids?
No problem. I guess the whole thing can be rather tricky. The KMT was the governing party of China when WWII ended and the UN was founded, but when the Communists came to power, the KMT really had no control over anything outside of Taiwan. I think 30 years ago this reality became apparent (there was no way China was a part of Taiwan) and the situation evolved to where it is now, where Taiwan is essentially a nation in every way but in name and officially a Chinese province. To your original point, only those original KMT members who followed Chiang from China (and perhaps their descendants) would likely regard China a part of Taiwan.
Anyhow, regardless of whatever formal stances that exist, the reality of matters can be far different; consequently, the truths about things are harder to discover.
If Chiang Kai-Shek was still alive, your statement would be correct. But he isn't. I don't know of any Taiwanese who would argue China is apart of Taiwan; those people must either be extremely elderly or dying. In truth, ~40% of Taiwanese would argue Taiwan is it's own nation, while the other 60% would be arguing that the Taiwanese should keep their yaps shut so China doesn't invade and ruin their day. (I'm basing the numbers off recent election results)
I think you're talking about the PRoC instituting proper industry controls, not the ROC. The difference? The former is China proper (mainland China, communist China) and the latter is Taiwan. While it's obvious China has some issues, made evident by the diethylene glycol laden toothpaste scandal, I'm pretty sure Taiwan has had systems in place for a while now to ensure something doesn't happen to their exported products. http://taiwanreview.nat.gov.tw/site/Tr/fp.asp?xItem=311&CtNode=128
The article I just linked shows evidence that Taiwan became aware of consumer confidence in goods in the late 80's, right around the time when it began a move toward formal democracy, and began addressing the issue with the emplacement of quality control measures.
The only problem I see in Taiwan, and this is going to be true in China and other Asian countries as well, is quality control of street vendor goods. In these situations, the vendor could be a small farmer who slaughters his own farm animals and sells them directly to consumers, bypassing whatever quality control measures the government would have in place. Of course, these things wouldn't be exported, and aren't as much of a concern to the rest of the world.
Well, first off, nowhere did I say that the US is perfect and is now incapable of making mistakes; I'm pretty sure no national government is immune to missteps. I just wanted to point out that missteps that have been made really shouldn't be repeated.
/. readers do the moderating here, and /. readers, like national governments, are not infallible. Next time, it might be a better idea to more clearly point out that there was no reason to mod the parent down, and, if anything, the parent should be moderated up for interesting points.
As to your complaint about the parent being modded down; he's been modded +1 interesting at this point. You should probably keep in mind that
Just because the poster might be American doesn't necessarily mean he bears some blame for the decimation of the Native American population in the US; how could you justify your comment (that you hope he isn't an American or US military supporter) if the poster is a 2nd generation descendant of an immigrant family?
Regardless, there's a point that you missed. The US obviously made mistakes in the past, and China looks like it's going to follow in the US' footsteps. Its treatment of Tibetans could be viewed analogous to US treatment of Native Americans during US westward expansion. While it is China's sovereign right to make itself a strong nation, I would hope it does so in a manner where it looks at mistakes made by other nations and avoids those pitfalls. So far, it's been failing. Case in point, diethylene glycol tainted toothpaste. To me, this seems to be a mirror of the snake oil salesmen from industrializing America, prior to governmental regulation of goods; it prompts the question, "Someone's made these mistakes before; why are you so intent on following in their footsteps?"
You're not taking into consideration the smoke coming from the burning tip of a cigarette. That stuff is unfiltered, undiluted, and research shows that carcinogens in this smoke are found at higher concentrations than in smoke being exhaled.http://www.ncbi.nlm.nih.gov/pubmed/16319363
Regardless, second hand smoke is certainly something I don't appreciate having to endure when I end up trailing or walking next to a smoker traveling in the same direction.
This is nowhere near designer baby capabilities that were prominently featured in GATTACA. This is simply the swapping out of somatic nuclear/genetic material from one cell to the other, taking advantage of the fact that mitochondrial lineages propogate clonally. This isn't a genetic disease in the sense that you're thinking; it's not a disease found in the human genome. It's a disease isolated to the genome of one of our organelles ("organs" for our cells).
Quick bio recap: I don't know if you remember much from high school biology, but there are 2 sources of DNA in our cells, mitochondria and nucleus. The experiment in the article is essentially swapping mitochondria between 2 people, allowing someone to live without a potentially life threatening mitochondrial defect. In other words, once the mitochondria have been swapped (or in this case, genomic DNA), the person SHOULD develop as he would if he had normal mitochondria in the first place. The only reason I say SHOULD is because we don't know how the RNA content of the genome receiving cell will affect development (as opposed to maternal RNA in the donor cell). But, the person's genetic make up would be the same in both scenarios. I cannot emphasize enough that there is no specificity in what genes are transferred; you cannot pick and choose what gene gets moved, and from what I know, I don't think you ever CAN. You're moving a whole GENOME here.
Now, unless different mitochondrial lineages can affect ATP production to fuel bodily/cellular processes, conferring an advantage somehow by having more efficient ATP production or what not, this type of treatment isn't going to generate the same class divisions and prejudices you saw in GATTACA. Lastly, the kid who results from this treatment wouldn't be a mutant; mutations are changes in DNA sequence, structure that prevent proper transcription and translation into protein. These would be examples of genetic diseases, which you mentioned earlier. To further elaborate, cancerous cells could be considered mutants because of a defect in it's DNA sequence, but a person who has cancer isn't a mutant; only a subset of that person's cells, the cancerous ones, are mutant.
Hrm. This is OT, but you wouldn't happen to be mrxak from AmbrosiaSW forums and Aftermath, would you?
The beginning was slow, but I'd argue the that the goal of the plot is only feasible if this first part occurred. Whoever followed your suggestion might be asking, "Why did Character A do this, and what's the significance behind Character A and B's relationship at the end of the movie?" I could imagine people asking, "What's the freakin' plot? Did it have one?!!!111!1" If they skipped the first part. And well, they've started asking this even after seeing the whole thing.
For those out there who are now worried; yes, it had a plot. My opinion of those who didn't discover the plot are that they are dumber than a box of rocks, which is entirely feasible. When a metal plate with 5 nubs arranged in a linear fashion appears on screen, and the response from one audience member is, "5 nipples? WTF? I don't get it", you begin to question the intelligence of some fellow moviegoers.
Ok, now, back to the original topic: I like stories, and perhaps it's because I get attached to characters easily; therefore, as long as SOME character development is present, I'll be able to relate/care for them in some way. What development in this movie was enough for me, and it certainly wouldn't've been the same for me if I skipped the beginning. The last 2 lines of the movie wouldn't have the same impact if I hadn't seen the beginning. In other words, don't skip it. Besides, even if the first 20 minutes is boring for you, I'm sure the other hour would more than make up for it.
That people who get nauseous from shakey cam simulated movies might get nauseous when watching Cloverfield.
Right?
Interesting point, which I admit I neglected in my post. This does prompt me to wonder if animal mitochondria could be removed from animal cells and be replaced with mitochondria from the human cell.
http://news.bbc.co.uk/2/hi/health/7193820.stm
I find this incredibly irritating. The specifics of the term "hybrid" are not elaborated upon and the continual use of the term"human-animal hybrid" allows for people to develop the notion that scientists out there are actually creating some monster chimeric creature.
Not. True. If you click on "Q&A Hybrid Embryos", found in the right hand nav bar, you'll see what I mean. I've provided the link below:
http://news.bbc.co.uk/2/hi/health/6233415.stm
This second link elaborates on why these eggs are considered "hybrid". Genetic material (DNA) is essentially removed from animal cells, leaving an empty nucleus and functional cellular machinery. In other words, you have a cell without DNA that looks very much like a human cell without it's DNA. The scientists then inject human DNA into the animal cell's nucleus; at this point the animal cell reads instructions off the DNA and carries them out. The end product is essentially A HUMAN CELL, but with left over proteins and cellular material generated from the old animal DNA.
This is FAR different from what people appear to be assuming. It's not going to generate some half cow-half human monster/creature, and does NOT "blur" the boundaries between humans and other species.
I like civil conversations! And visual effects! Pretty! :D
Fun talking to you, and best wishes
I won't question your beliefs, but I must say that I'd have other explanations for situations where I was able to succeed when failure appeared inevitable. I'd usually attribute it to last minute quick thinking, thorough analysis of mistakes, help from others, etc. Now whether these things that helped me succeed where I should have failed were an act of God, I don't know. Currently, I believe everything that happens is the result of some causative event resulting in some sort of effect. If I were to make observations supporting that God had a hand in saving my ass, repeatable and verifiable by others, I'd gladly start believing in him.
I think that's the key difference between you and I. You say believing is seeing, that enough things happened to you that you started believing, and it changed the way you see things. I, on the other hand, need to SEE (DNA and things too small exempt; we have ways of allowing us to see results. Same with quantum physics and other sciences; we must see results to verify). If I see something unexplainable happen (Ok, if someone makes a car magically vanish in my living room while I'm sitting in it, science goes out the window. I don't think it'll happen though), I will never attribute it to the supernatural, I'll attribute it to something I don't know. With regards to evolution, I didn't KNOW the genetic and biochemical basis that lent support to it, but I assumed that there was an explanation for it. Once I became familiar with chemistry, biochemistry, how DNA, RNA, and proteins functioned, how they were modular and could be assembled in many ways, how genes could be reassembled to produce new genes with new functions through protein machinery, things that scientific methods could allow me to see, it only lent support to my belief that evolutionary theory was valid.
Hopefully you can see that I'm comparing my growing belief in evolution's validity to your developing belief in God. I would like to stress that I'm not trying to change your point of view; though, if you want to understand why I believe so strongly in evolution's validity, I would encourage you to learn more about biochemistry, DNA, RNA, proteins, etc. (though I'm sure you're a busy man and have little time, but you seem very open minded, which I applaud).
Furthermore, I hope you can see my point; I actually think you already do. One needs to become familiar with both sides of the issue before arguing anything. It certainly irritates me to no end when people argue against evolution without some sort of scientific background in biology, chemistry, biochemistry, especially when I found it so vital to solidifying my support for evolutionary theory. Whatever "holes" I thought evolution had in high school (and they weren't really "holes", rather questions of "How does this work?") were answered in classes I had in college, by my experience in biology research labs. If you can look at all the supporting evidence and argue that evolution is not a valid theory, then I will listen to you, provided your rationale and logic are sound.
Unfortunately, I find it hard to say the same about religion. While I certainly need to be familiar with arguments for the existence of God, I'm not sure if I need to read the bible to be able to argue that there are no supporting observations (reproducible, verifiable, through tangible experiments, or observation of tangible things) that gods or a God exists. Surely I shouldn't misquote the bible to make my point; no one should misquote anything, everyone should get their facts straight if they intend to use them in argument. But when belief in God is only possible through a leap in faith, I cannot believe God did something when I believe that there is some alternative explanation grounded in the physical world. And this belief doesn't require any sort of "leap of faith", or blind trust, it just requires one to believe that there is a cause and effect that resulted in something to happen, the cause bound, restricted, and answers to the laws of the physical world.
Litera
Baloney. Complete and utter baloney. If you don't believe that the earth has limited resources and finite carrying capacity, get some common sense, read some Malthus, or take a look in a biology book. We might be fine for the nearby future, but an unsustainable earth appears to be an inevitability. The earth cannot, will not sustain human life forever. The birth of this planet only provided it with so many resources, and our unregulated consumption paints a very bleak future for us. The problem is further compounded by the fact that our consumption is not just unregulated, but also has the tendency to destroy other resources through unsustainable practices.
Furthermore, humanity should have hit carrying capacity already; were it not for the UNSUSTAINABLE breakthroughs brought by the Green Revolution in the 40's-60's, that brought us increased crop yields, we all would likely have experienced famine (in some shape or form) sometime in our lives. We currently face reaching a new carrying capacity with our ever increasing population. Now that many Green Revolution agricultural advances have been deemed unsustainable (environmentally unfriendly, rendering farmland useless), this future becomes exceedingly dire; we have yet to find a way to increase agricultural production that will compensate for our increased population and replace Green Revolution techniques.
Eh, big block of text. Hard to read. :(
In any case, you missed my points regarding observations supporting evolution.
The key is that I said, "observations that SUPPORT evolution", not "the observation OF evolution". And you make the assumption that I'm a God hating atheist (quoting you: "I was raised a God hating atheist TOO..."), which I am not. I'm quite open to the possibility of a god; all someone has to do is present me with observations that support that such a being exists.
Now, why do I believe that evolutionary theory is valid? The biochemistry behind life, specifically DNA to RNA to protein, the modularity of this system, and the outcomes that result from such modularity lend overwhelming support for evolution. While some try to liken this process to throwing parts of a car into a big bag, shaking it up, and having a car pop out (therefore, supposedly, disproving evolution), it's not so. Atoms are not car parts; from what I've learned about biochemistry, the very nature of atoms makes evolution very possible. Furthermore, while what I've learned does come from text, this text does come from experiments that have been verified by repeated and rigorous testing that produces the same results over and over.
So, what I'm trying to say here is that there are observations that SUPPORT the theory of evolution and lend it credibility. As a result, it is not necessary to actually SEE evolution to believe in it, so long as there are supporting observations.
Also, I want to address your accusation that science is funded by corporations. This certainly isn't always the case. Public universities are not funded by corporations (mostly government funded, though occasionally corporations will pitch in, though rarely), and a LOT of science is done at these public universities. These public universities, ie UC Berkeley, UCLA, etc., engage in scientific research to try better the lives of the public.
Also (and please excuse me, I'm jumping all over the place, trying to provide replies to your points as you have structured your response) to elaborate on WHY scientists can support something so confidently, I think I need to explain the scientific process, at least for biology:
1. Experiments are done
2. Results, methods, procedures, discussion are written
3. Items from #2 are incorporated into a paper that is published in a scientific journal by the researchers
4. Paper is read, experiments reproduced by other labs to verify veracity of findings
5. If discovery is groundbreaking enough, it is incorporated into text books.
The repetitions required to verify the veracity of scientific discoveries are what lead scientists to be very confident in their beliefs; you say you believe what you see rather than what you read, but in science, and science textbooks particularly, the text presents what is seen multiple times, in experiments reproduced by many DIFFERENT groups. In other words, we have faith in the abilities of our scientific peers, that they are competent people, that they have produced the same results supporting a theory. Of course this theory can be disproven, but until it is, repeated experiments giving such a theory validity will allow the theory to, well, be regarded as valid.
Lastly, I don't mean to sound patronizing in defining "theory" to you; the problem is scientific theory is not widely understood by many, particularly because "theory" in a scientific context does not have the same meaning as it does in everyday vocabulary. See: http://en.wikipedia.org/wiki/Theory
Whereas in common usage, theory is meant to describe an idea about how something possibly happened, the scientific context of the word implies that the idea about how something possibly happened has been validated by numerous observations supporting it; scientific theory is treated as "fact" until proven otherwise. Keep in mind, good scientists will never regard a theory as "fact", just as something we have V