Map Makers Admit Mistake in Showing Ice Cap Loss in Greenland

[bb113]

Regarding biodiversity and extinction events of the past. It is irrelevant that recoveries occurred. That's exactly analogous to saying, well, my house was leveled by a tornado, but it was rebuilt.

I don't follow, are you saying that using what is known about the past to inform future projections is invalid?

So? What about the year you lived in a motel while it was being rebuilt?

Yes, i explicitly say climate change would suck for those living at the time. I only wished to nuance what you said regarding extinction by making reference to past abrupt climate changes after which life on earth continued. Not sure what data there is on how well biodiversity recovers and how long this takes.

[1715080856]

1715080856

[FirstAscent]

http://ossfoundation.us/projects/environment/global-warming/dansgaard-oeschger-events

Of course, I still need to address your comments about extinction.

Yea, I actually read that. I was looking for more info about the effects of dansgaard-oeschger events on biodiversity but did not find anything easily. That link is just saying the current warming is not best explained as a D-O event. Nothing about the effect on biodiversity, which I would be interested in with regards to Punk-eek.

It's also stating that Fred Singer likes to push it. Recall Frederick Seitz? And Richard Lindzen? Those two, plus Singer are all sellouts to Big Oil. And the tobacco industry. Are they experts on climate change or are they experts on the dangers of tobacco smoke? The answer, of course, is it doesn't matter, because they obviously have other agendas.

I cited the IPCC...

That's a point against you, not for you. You see, I said earlier that you need to read the scientific literature. I said that twice. And you just now admitted that the only thing you read is the 2007 IPCC document. Is that the one that Richard Lindzen was a participant in, before he became disassociated with it?

I'm telling you (for about the fourth time) - stop trotting out material that is associated with paid charlatans aligned with the oil and tobacco industries, and start reading the scientific periodicals.

Well this was from the 2007 report, Lindzen was an author for the "clouds" chapter in 2001.

So you think the IPCC is not a good starting point? I only consider it a useful summary, but one must start somewhere.

Apparently you know more about this stuff than me... are the IPCC reports untrustworthy because some of the info in there is associated with paid charlatans?

I don't read the IPCC reports. And for all I know, the reference to the Dansgaard-Oeschger events was just background material, in an effort to be thorough.

Please, read the reputable scientific periodicals, either peer reviewed, or more mainstream ones like Scientific American. Do that for two years, or read back issues. For lack of a better way of putting it, you'll just feel that AGW makes sense. And conversely, every time you come across something that sounds like it is smugly pointing out that AGW must not be happening, dig a little deeper, and I can assure you - every single time - you'll discover it has ties to Big Oil, and even more strangely, the same people will have also been paid off by the tobacco companies years ago.

[FirstAscent]

Regarding biodiversity and extinction events of the past. It is irrelevant that recoveries occurred. That's exactly analogous to saying, well, my house was leveled by a tornado, but it was rebuilt.

I don't follow, are you saying that using what is known about the past to inform future projections is invalid?

So? What about the year you lived in a motel while it was being rebuilt?

Yes, i explicitly say climate change would suck for those living at the time. I only wished to nuance what you said regarding extinction by making reference to past abrupt climate changes after which life on earth continued. Not sure what data there is on how well biodiversity recovers and how long this takes.

Obviously, things will recover. For example, life recovered from the asteriod impact 65 million years ago. Tell that to a dinosaur though. The point is, just because recovery occurs, or things adapt, does not mean it will be beneficial to us.

And that's another thing. Just how much do you know about ecosystems, trophic cascades, natural productivity, and so on? A great example is how wolves provide us with clean water. You wouldn't think, but its true.

[bb113]

Ok, so now the IPCC is not a proper source of information... I wouldn't put too much stock in scientific american since it isn't peer reviewed. Do you have any recent review articles that you consider informative that I should use as a starting point? Basically I was using the 2007 IPCC as an extensive review article.

[bb113]

Regarding biodiversity and extinction events of the past. It is irrelevant that recoveries occurred. That's exactly analogous to saying, well, my house was leveled by a tornado, but it was rebuilt.

I don't follow, are you saying that using what is known about the past to inform future projections is invalid?

So? What about the year you lived in a motel while it was being rebuilt?

Yes, i explicitly say climate change would suck for those living at the time. I only wished to nuance what you said regarding extinction by making reference to past abrupt climate changes after which life on earth continued. Not sure what data there is on how well biodiversity recovers and how long this takes.

Obviously, things will recover. For example, life recovered from the asteriod impact 65 million years ago. Tell that to a dinosaur though. The point is, just because recovery occurs, or things adapt, does not mean it will be beneficial to us.

Agreed, I am not sure why you are arguing my post on this point then.

And that's another thing. Just how much do you know about ecosystems, trophic cascades, natural productivity, and so on? A great example is how wolves provide us with clean water. You wouldn't think, but its true.

I have an undergrad in pre-med (including a few classes on ecosystems, etc), as well as 4 years of gradschool pharmacology/neuroscience. In terms of informal education, nothing beyond wikipedia and documentaries. So... practically nothing, but probably more than the average person due to a background heavy in biology. How much do you know?

[FirstAscent]

Ok, so now the IPCC is not a proper source of information... I wouldn't put too much stock in scientific american since it isn't peer reviewed. Do you have any recent review articles that you consider informative that I should use as a starting point? Basically I was using the 2007 IPCC as an extensive review article.

Scientific American articles are summaries of scientific research written by scientists. It's up to you to follow up, if you so choose. I am getting tired of stating what is common sense among scientists, which is to read the popular scientific literature - something you have admitted on several occasions that you do not do. I cannot help you further on this matter.

[bb113]

I must misunderstand you. Are you claiming Scientific American is proper scientific literature but the IPCC reports are not?

Is there a review article you recommend?

[FirstAscent]

I have an undergrad in pre-med (including a few classes on ecosystems, etc), as well as 4 years of gradschool pharmacology/neuroscience. In terms of informal education, nothing beyond wikipedia and documentaries. So... practically nothing, but probably more than the average person due to a background heavy in biology. How much do you know?

I've never had a class on ecosystems. And I've certainly never had a course on neuroscience. And I nearly failed high school algebra.

Now, do you want to discuss riparian zones or trophic cascades? Analytic geometry? Finding the roots of 6th degree polynomials? Sampling over the hemisphere as a method of integration in calculating total net energy falling upon a surface? Or would you like to discuss ion flow between synaptic connections, and the suitability of artificial neural networks vs. biological neural networks as a means of simulating brain activity? Perhaps you'd like to discuss STDP (Spike timed dependent plasticity) as a plausible mathematical model for representing the change in synaptic weights and how it models learning in brains?

The bottom line: your background is irrelevant, and so is mine.

[FirstAscent]

I must misunderstand you.

Obviously.

[bb113]

I have an undergrad in pre-med (including a few classes on ecosystems, etc), as well as 4 years of gradschool pharmacology/neuroscience. In terms of informal education, nothing beyond wikipedia and documentaries. So... practically nothing, but probably more than the average person due to a background heavy in biology. How much do you know?

I've never had a class on ecosystems. And I've certainly never had a course on neuroscience. And I nearly failed high school algebra.

Now, do you want to discuss riparian zones or trophic cascades? Analytic geometry? Finding the roots of 6th degree polynomials? Sampling over the hemisphere as a method of integration in calculating total net energy falling upon a surface? Or would you like to discuss ion flow between synaptic connections, and the suitability of artificial neural networks vs. biological neural networks as a means of simulating brain activity? Perhaps you'd like to discuss STDP (Spike timed dependent plasticity) as a plausible mathematical model for representing the change in synaptic weights and how it models learning in brains?

The bottom line: your background is irrelevant, and so is mine.

It is somewhat relevant in being able to interpret the literature. But you are right, the discussion should not be based on our backgrounds, but what we contribute to the conversation and most importantly the data. Actually I would love to discuss STDP, especially with regards to the role it may play in recovery after brain injury... make a thread.
By the way, sometimes I feel like I am arguing with a bot here

[Matthew N. Wright]

Hey guys, guess what! This entirely interesting and serious debate is featured here! https://bitcointalk.org/index.php?topic=64611.msg758894#msg758894

[bb113]

Hey guys, guess what! This entirely interesting and serious debate is featured here! https://bitcointalk.org/index.php?topic=64611.msg758894#msg758894

Haha I saw that. My point is supposed to be your point though... too bad it got lost in translation.

[FirstAscent]

STDP is interesting as an alternative to the methods presented by Rumelhart and McClelland in their classic PDP texts (which I studied back in the late '80s), and, in my opinion, has far more applicability to simulation of the brain than the simpler back propagation models proposed by Rumelhart.

As for wolves, I suggest you learn about the effects wolves have on riparian zones, and why it matters.

[bb113]

Ok, why not go off topic... matthew thinks this thread is dumb anyway. In simulating neural activity (which I know little about), how detailed are the models of dendritic arbor and spines?

Warning, jargon below:
I mean do they attempt to model all the postsynaptic feedback factors (AMPA and NMDA receptors, various GPCRs and G-proteins, etc) to level of the cytoskeleton, or is it just calcium influx -> greater weight? Also, how is the weight of each synapse adjusted according to distance and number of branch points from the soma, is this corrected for dendritic thickness?

What would the effect on firing rate be if a certain treatment increased the proportion of distal dendritic branches while decreasing the number proximal to the soma (i.e. results of sholl analysis)? Assume same input firing rate, homogenous spine density, etc.

[bb113]

With regards to my last question. I should say that on the face of it, it appears to me the neuron has become "less certain" about which inputs to listen to, so will show a more variable response to any given input.

[FlipPro]

Ok, why not go off topic... matthew thinks this thread is dumb anyway. In simulating neural activity (which I know little about), how detailed are the models of dendritic arbor and spines?

Warning, jargon below:
I mean do they attempt to model all the postsynaptic feedback factors (AMPA and NMDA receptors, various GPCRs and G-proteins, etc) to level of the cytoskeleton, or is it just calcium influx -> greater weight? Also, how is the weight of each synapse adjusted according to distance and number of branch points from the soma, is this corrected for dendritic thickness?

What would the effect on firing rate be if a certain treatment increased the proportion of distal dendritic branches while decreasing the number proximal to the soma (i.e. results of sholl analysis)? Assume same input firing rate, homogenous spine density, etc.

You gotta be paid by BP.

Just gotta...

[Matthew N. Wright]

To sum things up, pollution is horrible and highly avoidable. Climate change can be more or less controlled by science, but the mini seasons and long seasons will be naturally hot and naturally cold, eventually freezing us all to death or burning us all up. Such is the galactic alignment we inherited. There are way better arguments for clean energy than trumped up, widely speculated claims.

[bb113]

Ok, why not go off topic... matthew thinks this thread is dumb anyway. In simulating neural activity (which I know little about), how detailed are the models of dendritic arbor and spines?

Warning, jargon below:
I mean do they attempt to model all the postsynaptic feedback factors (AMPA and NMDA receptors, various GPCRs and G-proteins, etc) to level of the cytoskeleton, or is it just calcium influx -> greater weight? Also, how is the weight of each synapse adjusted according to distance and number of branch points from the soma, is this corrected for dendritic thickness?

What would the effect on firing rate be if a certain treatment increased the proportion of distal dendritic branches while decreasing the number proximal to the soma (i.e. results of sholl analysis)? Assume same input firing rate, homogenous spine density, etc.

You gotta be paid by BP.

Just gotta...

I wish I got paid for this. I expect to take on some douchebaggage for the post above. But it may be worth it.

To sum things up, pollution is horrible and highly avoidable. Climate change can be more or less controlled by science, but the mini seasons and long seasons will be naturally hot and naturally cold, eventually freezing us all to death or burning us all up. Such is the galactic alignment we inherited. There are way better arguments for clean energy than trumped up, widely speculated claims.

How can climate change be controlled by science?

[FirstAscent]

Ok, why not go off topic... matthew thinks this thread is dumb anyway. In simulating neural activity (which I know little about), how detailed are the models of dendritic arbor and spines?

Warning, jargon below:
I mean do they attempt to model all the postsynaptic feedback factors (AMPA and NMDA receptors, various GPCRs and G-proteins, etc) to level of the cytoskeleton, or is it just calcium influx -> greater weight? Also, how is the weight of each synapse adjusted according to distance and number of branch points from the soma, is this corrected for dendritic thickness?

What would the effect on firing rate be if a certain treatment increased the proportion of distal dendritic branches while decreasing the number proximal to the soma (i.e. results of sholl analysis)? Assume same input firing rate, homogenous spine density, etc.

If you're genuinely interested, read everything you can about the Bluebrain project: http://bluebrain.epfl.ch/

They are using an IBM supercomputer which has enough resources to dedicate the equivalent of one laptop per neuron, each having perhaps 5,000 synaptic connections for the simulation of one cortical column. Watch the simulation of a cortical column completely built from scans of slices of a rat's brain: http://www.youtube.com/watch?v=xHi9oLzvD8E

Google PDF documents where Henry Markram is a coauthor. Watch the TED video he gave. Their goal is build a complete human brain. As for some of your technical questions, I don't have the answers.

I personally was implementing STDP and an empirical model to simulate a neuron's action potential, with very efficient storage of synaptic connections, simulating the length of axons and dendrites by storing them in a list, sorted by length, such that the program could traverse the list, adding in the delay from one to the next, and thus the program would always know the next synapse which would fire, and these pulses would accumulate to each respective receiving neuron, such that it could be calculated which neuron would fire next, thus distributing pulses further on down the line.

[FirstAscent]

While on the subject of brains, from a philosophical viewpoint, do you buy Dennett's arguments, or do you prefer the ideas articulated by Chalmers? Or, do you think Hameroff's studies, inspired by Penrose are the ticket? While I think Hameroff is onto something, given his credentials and line of study, I think he only seems to be addressing the 'how', as opposed to the 'why'. It's Dennett's and Chalmers' sparring that really goes after the Hard Problem. As for me personally, while I admit that Dennett is a great writer, and his stuff is really interesting to read, in the end, his answers are just unsatisfactory, although he seems so insistent that he's answered the big question. That's why, ultimately, I find Chalmers' discussion on the subject to be the most interesting.