VOU DEIXAR O MEU CORAÇÃO PARA VOCÊ!.
ATÉ SEMANA QUE VEM.
DEIXO UM ABRAÇO E UM BEIJO NO SEU CORAÇÃO.
Thursday, October 7, 2010
VIAJANDO PARA FORTALEZA-
VOU DEIXAR O MEU CORAÇÃO PARA VOCÊ!.
ATÉ SEMANA QUE VEM.
DEIXO UM ABRAÇO E UM BEIJO NO SEU CORAÇÃO.
Israel and Palestine are Both Fighting Back...?
There are three basic schools of thought on the Israel / Palestine thing.- Those evil Israelis are out to destroy Palestine, and the Palestinians are just fighting back.
- Those evil Palestinians are out to destroy Israel, and the Israelis are just fighting back.
- It's a cycle of violence, where both sides are fighting back against the other.
Wouldn't it be handy if science could provide an answer? According to the authors of a new paper in Proceedings of the National Academy of Science, the "cycle" school is right: both sides are fighting back against the other: Both sides retaliate in the Israeli-Palestinian conflict.
The authors (from Switzerland, Israel and the USA) took data on daily fatalities on both sides, and also of daily launches of Palestinian "Qassam" rockets at Israel. The data run from 2001, the start of the current round of unpleasantness, to late 2008, the Gaza War.
They looked to see whether the number of events that happened on a certain day predicted the number of events caused by the other side on the following days, i.e. whether a Palestinian death caused the Palestinians to retaliate by firing more rockets and killing more Israelis, and vice versa.
What happened? They found that both sides were more likely to launch attacks on the days following a death on their own side. The exception to this rule was that Israel did not noticeably retaliate against Qassam launches. This is perhaps because Qassams are so ineffective: out of 3,645 recorded launches, they killed 15 people.
These graphs show the number of "extra" actions on the days following a event, averaged over the whole 8 years, according to a statistical method called the Impulse Response Function. Note that the absolute size of the effects is larger for the Israeli retaliations (the Y axis is bigger); there were a total of 4,874 Palestinian fatalities and 1,062 Israeli fatalitiesThe authors then used another method called Vector Autoregression to discover more about the relationship. In theory, this method controls for the past history of actions by a given side, so that it reveals the number of actions independently caused by the opposing side.
the number of Qassams fired increases by 6% on the first day after a single killing of a Palestinian by Israel; the probability of any Qassams being fired increases by 11%; and the probability of any Israelis being killed by Palestinians increases by 10%. Conversely, 1 day after the killing of a single Israeli by Palestinians, the number of Palestinians killed by Israel increases by 9%, and the probability of any Palestinians being killed increases by 20%What are we to make of this? This is a good paper as far as it goes, and it casts doubt on earlier analyses finding that Israel is retaliating against Palestinians but not vice versa. However, the inherent problem with all of this research (beyond the fact that it's all based on correlations and can only indirectly imply causation), is that it focuses on individual acts of violence. The authors say, citing surveys, that
....retaliation accounts for a larger fraction of Palestinian compared with Israeli aggression: in the levels specification, 10% of all Qassam rockets can be attributed to prior Israeli attacks on Palestinians, but only 4% of killings of Palestinians by Israel can be attributed to prior Palestinian attacks on Israel.... 6% of all days on which Palestinians attack Israel with rockets, and 5% of all days on which they attack by killing Israelis, can be attributed to retaliation; in contrast, this is true for only 2% of all days on which Israel kills Palestinians.
Over one half of Israelis and three quarters of Palestinians think the other side seeks to take over their land. When accounting for their own acts of aggression, Israelis often claim to be merely responding to Palestinian violence, and Palestinians often see themselves as simply reacting to Israeli violence.But I don't think many Israelis would argue that the IDF only kills individual Palestinians as a reflex reaction to a particular attack. They're claiming that the whole conflict is a defensive one, that the Palestinians are the aggressors, but that doesn't rule out their taking the initiative on a tactical level e.g. in destroying Palestinian military capabilities before they have a chance to attack. And vice versa on the other side.
WW2 was a war of aggression by the Axis powers, but that doesn't mean that the Allies only killed Axis soldiers after they'd attacked a certain place. The Allies were on the offensive for the second half of the war, and eventually invaded the Axis's own homelands, but it was still a defensive war, because the Axis were responsible for it.
For Israel and for Palestine, the other guys are to blame for the whole thing. Who's right, if anyone, is fundamentally a historical, political and ethical question, that can't be answered by looking at day-to-day variations in who's shooting when.
Comment Policy: Please only comment if you've got something to say about this paper, or related research. Comments that are just making the case for or against Israel will get deleted.
Haushofer J, Biletzki A, & Kanwisher N (2010). Both sides retaliate in the Israeli-Palestinian conflict. Proceedings of the National Academy of Sciences of the United States of America PMID: 20921415
Israel and Palestine are Both Fighting Back...?
There are three basic schools of thought on the Israel / Palestine thing.- Those evil Israelis are out to destroy Palestine, and the Palestinians are just fighting back.
- Those evil Palestinians are out to destroy Israel, and the Israelis are just fighting back.
- It's a cycle of violence, where both sides are fighting back against the other.
Wouldn't it be handy if science could provide an answer? According to the authors of a new paper in Proceedings of the National Academy of Science, the "cycle" school is right: both sides are fighting back against the other: Both sides retaliate in the Israeli-Palestinian conflict.
The authors (from Switzerland, Israel and the USA) took data on daily fatalities on both sides, and also of daily launches of Palestinian "Qassam" rockets at Israel. The data run from 2001, the start of the current round of unpleasantness, to late 2008, the Gaza War.
They looked to see whether the number of events that happened on a certain day predicted the number of events caused by the other side on the following days, i.e. whether a Palestinian death caused the Palestinians to retaliate by firing more rockets and killing more Israelis, and vice versa.
What happened? They found that both sides were more likely to launch attacks on the days following a death on their own side. The exception to this rule was that Israel did not noticeably retaliate against Qassam launches. This is perhaps because Qassams are so ineffective: out of 3,645 recorded launches, they killed 15 people.
These graphs show the number of "extra" actions on the days following a event, averaged over the whole 8 years, according to a statistical method called the Impulse Response Function. Note that the absolute size of the effects is larger for the Israeli retaliations (the Y axis is bigger); there were a total of 4,874 Palestinian fatalities and 1,062 Israeli fatalitiesThe authors then used another method called Vector Autoregression to discover more about the relationship. In theory, this method controls for the past history of actions by a given side, so that it reveals the number of actions independently caused by the opposing side.
the number of Qassams fired increases by 6% on the first day after a single killing of a Palestinian by Israel; the probability of any Qassams being fired increases by 11%; and the probability of any Israelis being killed by Palestinians increases by 10%. Conversely, 1 day after the killing of a single Israeli by Palestinians, the number of Palestinians killed by Israel increases by 9%, and the probability of any Palestinians being killed increases by 20%What are we to make of this? This is a good paper as far as it goes, and it casts doubt on earlier analyses finding that Israel is retaliating against Palestinians but not vice versa. However, the inherent problem with all of this research (beyond the fact that it's all based on correlations and can only indirectly imply causation), is that it focuses on individual acts of violence. The authors say, citing surveys, that
....retaliation accounts for a larger fraction of Palestinian compared with Israeli aggression: in the levels specification, 10% of all Qassam rockets can be attributed to prior Israeli attacks on Palestinians, but only 4% of killings of Palestinians by Israel can be attributed to prior Palestinian attacks on Israel.... 6% of all days on which Palestinians attack Israel with rockets, and 5% of all days on which they attack by killing Israelis, can be attributed to retaliation; in contrast, this is true for only 2% of all days on which Israel kills Palestinians.
Over one half of Israelis and three quarters of Palestinians think the other side seeks to take over their land. When accounting for their own acts of aggression, Israelis often claim to be merely responding to Palestinian violence, and Palestinians often see themselves as simply reacting to Israeli violence.But I don't think many Israelis would argue that the IDF only kills individual Palestinians as a reflex reaction to a particular attack. They're claiming that the whole conflict is a defensive one, that the Palestinians are the aggressors, but that doesn't rule out their taking the initiative on a tactical level e.g. in destroying Palestinian military capabilities before they have a chance to attack. And vice versa on the other side.
WW2 was a war of aggression by the Axis powers, but that doesn't mean that the Allies only killed Axis soldiers after they'd attacked a certain place. The Allies were on the offensive for the second half of the war, and eventually invaded the Axis's own homelands, but it was still a defensive war, because the Axis were responsible for it.
For Israel and for Palestine, the other guys are to blame for the whole thing. Who's right, if anyone, is fundamentally a historical, political and ethical question, that can't be answered by looking at day-to-day variations in who's shooting when.
Comment Policy: Please only comment if you've got something to say about this paper, or related research. Comments that are just making the case for or against Israel will get deleted.
Haushofer J, Biletzki A, & Kanwisher N (2010). Both sides retaliate in the Israeli-Palestinian conflict. Proceedings of the National Academy of Sciences of the United States of America PMID: 20921415
Tuesday, October 5, 2010
UM ABRAÇO MUITO CARINHOSO A TODOS.. DEIXO O MEU CORAÇÃO!!!
MEUS QUERIDOS AMIGOS(AS), VENHO AGRADECER PELO BLOG TODAS AS VISITAS CARINHOSAS DE VOCES. ESTOU SEM TEMPO DE RETRIBUIR. EM CONSIDERAÇÃO A NOSSA AMIZADE DEIXO ESTE RECADINHO POR AQUI. ASSIM QUE PUDER VOU RETRIBUIR COM MUITO CARINHO A TODOS. NÃO SEI SE SERÁ POSSIVEL ESTA SEMANA. PEÇO DESCULPAS PELA FALTA. MAS QUERO QUE SAIBA QUE MESMO NÃO VINDO AQUI, VOCÊ ESTÁRA SEMPRE COMIGO, NO PESAMENTO E CORAÇÃO.
EM NOME DA NOSSA AMIZADE LHE OFEREÇO ESTE SELO.
DE CORAÇÃO PARA CORAÇÃO É O QUE SOMOS.
AMIGOS DE VERDADE!!!
GOSTARIA SÓ MAIS UM FAVORZINHO.....
ESTOU CONCORRENDO AO BLOG DESTAQUE NO BLOG BLOÍNQUÊS.
CONTO COM SEU VOTO NESTE ENDEREÇO
blog ainda concorreendo ao destaque do mês na comunidade do Bloínquês, peço aos amigos de votarem no endereço... http://www.orkut.com.br/Main#CommPollVote?cmm=96338005&pct=1286116861&pid=778205604.CONTO COM SEU VOTO NESTE ENDEREÇO
OBRIGADA A TODOS.
AGRADEÇO A SUA COMPANHIA!!!
Sinal de Liberdade-uma expressão de sentimento-
Brand New Cortical Neurons
Are new neurons created in the adult brain?
For a long time, everyone thought the answer was "no". Then, about 15 years ago, we learned that neurogenesis does occur in the adult brain, but it was thought to be limited to two very small regions, the dentate gyrus and the sub-ventricular zone. Except in cases of injury, when adult neurogenesis had been reported elsewhere.
Now Guo et al look set to overturn this orthodoxy in a new Journal of Neuroscience paper, as they found ongoing neurogenesis in healthy adult brains in an area called the piriform cortex, part of the cerebral cortex.
The key to the discovery was oligodendrocyte progenitor cells (OPCs). OPCs were previously believed to only be able to turn into cells called oligodendrocytes, which are not neurons, but glia; glia are a kind of support crew for the brain.
But Guo et al show convincingly (with the help of genetically modified mice) that OPCs do become neurons in the piriform cortex of adult mice. Once they've been "born", these new neurons mature into functional pyramidal cells - they form synapses with other neurons, and otherwise seem to be perfectly happy, and they survived for hundreds of days (i.e. most of a mouse's lifetime).
The methods they used are complex but the crucial result was that they observed pyramidal cells expression yellow fluorescent protein, in mice genetically modified to express this protein only in OPCs; the picture above this post is one of these "yellow" (I know, it looks green to me) neurons.
This isn't the first paper to report neurogenesis in the adult mouse piriform cortex - a different group did so in 2008, but then two other experiments published later that year failed to confirm the result, so it's remained controversial. Whether this will end the controversy is uncertain but it looks pretty solid to me.
What does it all mean? The piriform cortex is a bit of a weird area, as while it's part of the cerebral cortex, the most "complex" part of the brain, it is evolutionary very old, and quite unlike the neocortex which is by far the largest part of the brain in humans.
The piriform is involved in the sense of smell, which is very important for mice, not so much in humans. We do have a piriform cortex, but it's tiny. Whether adult neurogenesis also occurs in the neocortex is the next big question...
Guo F, Maeda Y, Ma J, Xu J, Horiuchi M, Miers L, Vaccarino F, & Pleasure D (2010). Pyramidal neurons are generated from oligodendroglial progenitor cells in adult piriform cortex. The Journal of neuroscience : the official journal of the Society for Neuroscience, 30 (36), 12036-49 PMID: 20826667
For a long time, everyone thought the answer was "no". Then, about 15 years ago, we learned that neurogenesis does occur in the adult brain, but it was thought to be limited to two very small regions, the dentate gyrus and the sub-ventricular zone. Except in cases of injury, when adult neurogenesis had been reported elsewhere.Now Guo et al look set to overturn this orthodoxy in a new Journal of Neuroscience paper, as they found ongoing neurogenesis in healthy adult brains in an area called the piriform cortex, part of the cerebral cortex.
The key to the discovery was oligodendrocyte progenitor cells (OPCs). OPCs were previously believed to only be able to turn into cells called oligodendrocytes, which are not neurons, but glia; glia are a kind of support crew for the brain.
But Guo et al show convincingly (with the help of genetically modified mice) that OPCs do become neurons in the piriform cortex of adult mice. Once they've been "born", these new neurons mature into functional pyramidal cells - they form synapses with other neurons, and otherwise seem to be perfectly happy, and they survived for hundreds of days (i.e. most of a mouse's lifetime).
The methods they used are complex but the crucial result was that they observed pyramidal cells expression yellow fluorescent protein, in mice genetically modified to express this protein only in OPCs; the picture above this post is one of these "yellow" (I know, it looks green to me) neurons.
This isn't the first paper to report neurogenesis in the adult mouse piriform cortex - a different group did so in 2008, but then two other experiments published later that year failed to confirm the result, so it's remained controversial. Whether this will end the controversy is uncertain but it looks pretty solid to me.
What does it all mean? The piriform cortex is a bit of a weird area, as while it's part of the cerebral cortex, the most "complex" part of the brain, it is evolutionary very old, and quite unlike the neocortex which is by far the largest part of the brain in humans.
The piriform is involved in the sense of smell, which is very important for mice, not so much in humans. We do have a piriform cortex, but it's tiny. Whether adult neurogenesis also occurs in the neocortex is the next big question...
Guo F, Maeda Y, Ma J, Xu J, Horiuchi M, Miers L, Vaccarino F, & Pleasure D (2010). Pyramidal neurons are generated from oligodendroglial progenitor cells in adult piriform cortex. The Journal of neuroscience : the official journal of the Society for Neuroscience, 30 (36), 12036-49 PMID: 20826667
Brand New Cortical Neurons
Are new neurons created in the adult brain?
For a long time, everyone thought the answer was "no". Then, about 15 years ago, we learned that neurogenesis does occur in the adult brain, but it was thought to be limited to two very small regions, the dentate gyrus and the sub-ventricular zone. Except in cases of injury, when adult neurogenesis had been reported elsewhere.
Now Guo et al look set to overturn this orthodoxy in a new Journal of Neuroscience paper, as they found ongoing neurogenesis in healthy adult brains in an area called the piriform cortex, part of the cerebral cortex.
The key to the discovery was oligodendrocyte progenitor cells (OPCs). OPCs were previously believed to only be able to turn into cells called oligodendrocytes, which are not neurons, but glia; glia are a kind of support crew for the brain.
But Guo et al show convincingly (with the help of genetically modified mice) that OPCs do become neurons in the piriform cortex of adult mice. Once they've been "born", these new neurons mature into functional pyramidal cells - they form synapses with other neurons, and otherwise seem to be perfectly happy, and they survived for hundreds of days (i.e. most of a mouse's lifetime).
The methods they used are complex but the crucial result was that they observed pyramidal cells expression yellow fluorescent protein, in mice genetically modified to express this protein only in OPCs; the picture above this post is one of these "yellow" (I know, it looks green to me) neurons.
This isn't the first paper to report neurogenesis in the adult mouse piriform cortex - a different group did so in 2008, but then two other experiments published later that year failed to confirm the result, so it's remained controversial. Whether this will end the controversy is uncertain but it looks pretty solid to me.
What does it all mean? The piriform cortex is a bit of a weird area, as while it's part of the cerebral cortex, the most "complex" part of the brain, it is evolutionary very old, and quite unlike the neocortex which is by far the largest part of the brain in humans.
The piriform is involved in the sense of smell, which is very important for mice, not so much in humans. We do have a piriform cortex, but it's tiny. Whether adult neurogenesis also occurs in the neocortex is the next big question...
Guo F, Maeda Y, Ma J, Xu J, Horiuchi M, Miers L, Vaccarino F, & Pleasure D (2010). Pyramidal neurons are generated from oligodendroglial progenitor cells in adult piriform cortex. The Journal of neuroscience : the official journal of the Society for Neuroscience, 30 (36), 12036-49 PMID: 20826667
For a long time, everyone thought the answer was "no". Then, about 15 years ago, we learned that neurogenesis does occur in the adult brain, but it was thought to be limited to two very small regions, the dentate gyrus and the sub-ventricular zone. Except in cases of injury, when adult neurogenesis had been reported elsewhere.Now Guo et al look set to overturn this orthodoxy in a new Journal of Neuroscience paper, as they found ongoing neurogenesis in healthy adult brains in an area called the piriform cortex, part of the cerebral cortex.
The key to the discovery was oligodendrocyte progenitor cells (OPCs). OPCs were previously believed to only be able to turn into cells called oligodendrocytes, which are not neurons, but glia; glia are a kind of support crew for the brain.
But Guo et al show convincingly (with the help of genetically modified mice) that OPCs do become neurons in the piriform cortex of adult mice. Once they've been "born", these new neurons mature into functional pyramidal cells - they form synapses with other neurons, and otherwise seem to be perfectly happy, and they survived for hundreds of days (i.e. most of a mouse's lifetime).
The methods they used are complex but the crucial result was that they observed pyramidal cells expression yellow fluorescent protein, in mice genetically modified to express this protein only in OPCs; the picture above this post is one of these "yellow" (I know, it looks green to me) neurons.
This isn't the first paper to report neurogenesis in the adult mouse piriform cortex - a different group did so in 2008, but then two other experiments published later that year failed to confirm the result, so it's remained controversial. Whether this will end the controversy is uncertain but it looks pretty solid to me.
What does it all mean? The piriform cortex is a bit of a weird area, as while it's part of the cerebral cortex, the most "complex" part of the brain, it is evolutionary very old, and quite unlike the neocortex which is by far the largest part of the brain in humans.
The piriform is involved in the sense of smell, which is very important for mice, not so much in humans. We do have a piriform cortex, but it's tiny. Whether adult neurogenesis also occurs in the neocortex is the next big question...
Guo F, Maeda Y, Ma J, Xu J, Horiuchi M, Miers L, Vaccarino F, & Pleasure D (2010). Pyramidal neurons are generated from oligodendroglial progenitor cells in adult piriform cortex. The Journal of neuroscience : the official journal of the Society for Neuroscience, 30 (36), 12036-49 PMID: 20826667
How To Sell An Idea
You've got an idea: a new way of doing things; a change; a paradigm shift. It might work, it might be no better than what we've got already, or it might end up being a disaster.
The honest way to present your proposal would be to admit its novelty, and hence the uncertainty: this is a new idea I had, I can't promise anything, but here are my reasons for thinking it's worth a try, here are the likely costs and benefits, here are the alternatives.
However, let's suppose you don't want to do that. That's hard work, and if your idea is crap, people could tell. How else could you convince them? By making it seem as though it's not a new idea at all.
You could dress your idea up as:
Of course, there are plenty of changes that really are these things, to various degrees. Sometimes the past was glorious, relatively speaking (France 1942 springs to mind); sometimes we do need to catch up.
But every new idea still has an element of risk. Nothing has ever been tried and tested in the exact circumstances that we face now, because those circumstances have never existed before. Just because it worked before, or elsewhere, in a situation that we think is similar, is no guarantee. There are only degrees of certainty.
This doesn't mean we can't decide what to do, or that we shouldn't change anything. Not changing things is a plan of action in itself, anyway. The point is that we ought to be willing to try stuff that might not work, our guide to what's likely to happen being the evidence on what's worked before, critically appraised. "I don't know" is not a dirty phrase.
The honest way to present your proposal would be to admit its novelty, and hence the uncertainty: this is a new idea I had, I can't promise anything, but here are my reasons for thinking it's worth a try, here are the likely costs and benefits, here are the alternatives.However, let's suppose you don't want to do that. That's hard work, and if your idea is crap, people could tell. How else could you convince them? By making it seem as though it's not a new idea at all.
You could dress your idea up as:
- the glorious past. Your idea is nothing more than how we did things back in the golden age, when everything was great. For some reason, people strayed from the true path, and things went bad. We should go back to the the good old days. It worked then, so it'll work now. You'll use words like: restoring, reviving, regaining, renewing... "re" is your friend.
- the next step. Your idea is just the logical progression of what we're already doing. Things used to be bad, and then they started to change, and get better. Let's make them even better, by doing more of the same. It's inevitable, anyway: you can't stop history. You'll use words like: progress, forward, advance, build, grow...
- catching up. You're just saying we should bring stuff into line with the way things are done elsewhere, which as we know, is working well. It's not even a matter of moving forward, so much as keeping up. It would be weird not to change. We don't want to be dinosaurs. You'll use words like: modernization, rationalization, reform...
- keeping things the same. Things are fine right now, and don't need improving. But in order for things to stay great, we must adapt to changing circumstances, so we'll have to make a few adjustments, but don't worry, fundamentally things are going to stay just as they are. You'll use words like: preserving, maintaining, protecting, upholding, strengthening...
Of course, there are plenty of changes that really are these things, to various degrees. Sometimes the past was glorious, relatively speaking (France 1942 springs to mind); sometimes we do need to catch up.
But every new idea still has an element of risk. Nothing has ever been tried and tested in the exact circumstances that we face now, because those circumstances have never existed before. Just because it worked before, or elsewhere, in a situation that we think is similar, is no guarantee. There are only degrees of certainty.
This doesn't mean we can't decide what to do, or that we shouldn't change anything. Not changing things is a plan of action in itself, anyway. The point is that we ought to be willing to try stuff that might not work, our guide to what's likely to happen being the evidence on what's worked before, critically appraised. "I don't know" is not a dirty phrase.
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