Monday, August 31, 2015

interesting snippet from an article from this year(2015)

"There’s been another shake-up in our understanding of the causes of cardiovascular disease. Cholesterol is still king. But it now shares explanatory power with a swarm of bacteria resident in the digestive tract. The first studies of these bacteria (reviewed here) found direct links between the chemical product of their metabolism and the vascular events leading to heart attack. Now studies are linking these bacteria to heart failure and even chronic kidney disease."-link

cool vid

Sunday, August 23, 2015

post on vr on kurzweilai

The fact that they accomplish things is what makes them real.-Spikosauropod

In the end it is not the effects on unconscious matter that matters, wind blowing in a planet never to be inhabited is meaningless. What actually matters is the effects upon conscious agents. And [full immersion] virtual reality allows direct manipulation of conscious states. Pleasure, pain, myriad experiences.-link

Tuesday, August 18, 2015

Two interesting articles


On examination, they found that rat vibrissal cortex comprises about 500,000 neurons, the number and 3D distribution being remarkably preserved across animals. More importantly, the number of neurons per cortical column varied between 10,000 and 30,000 within individual animals.

“Instead, the organization of the cerebral cortex seems to be shaped by the information obtained at the peripheral sensory sheet, a finding that may pertain to other sensory systems and species, including people.-link
 This one suggests that the size of hypercolumns or macrocolumns is not constant but based on input. 

The models suggest that cortical circuitry interconnects most neurons across cortical columns, rather than within and that these “trans-columnar” networks are not uniformly structured: they are highly specialized and integrate signals from multiple sensory receptors.
 Neurons of all cell types projected the majority of their axon — the part of the neuron that transmits information to other neurons — far beyond the borders of the cortical column they were located in. That means information from a single whisker spreads into multiple cortical columns.-link
 Another interesting finding, showing the importance of transcolumnar connectivity

Sunday, August 9, 2015

post on kurzweilai forums related to aging

I think we have solved the mystery of ageing. Ageing is what happens when imperfections in the body's ability to repair itself and clean up the waste which it produces is allowed to accumulate. Why is it allowed to accumulate? Because the selfish gene does not give a fig about damage or waste which negatively affects survival rates only after that period of time in which reproduction is likely to occur. As there are several very different causes of damage and waste we cannot look to one single way to tackle the causes of ageing but require instead a range of techniques for dealing with each of the seven deadly sins of ageing.-Extropia DaSilva
Some of the most metabolically active cells, and thus the ones producing the highest amount of damaging byproducts of metabolism, cells that do not even divide to dilute this damage, are neurons. What have we seen? Even with the exact same genes, nondividing neuron cells can live over twice as long as the original host when transplanted between species. That tells you that in some cases some of the cells already have active mechanisms sufficient to last at least twice as long as the host does. So what is going on? At the cellular level it seems over twice the lifespan is possible with existing genes, in some species, if the right genes were being activated.
The problem with Aubrey's view is that one might say the same SENS protocol might also be required to say triple a long lived species lifespan, say a bonobo's lifespan from 40 years to 120 years, yet we know humans with less than 2% genetic difference(most of the difference likely unrelated to lifespan extension.), accomplished this and many SENS protocols were not necessary. We also know that some species that appear not to age appear not to have undertaken some of the sens protocols like mitosens or WILT.
It is also said that there are closely related species were one ages and the other does not, suggesting that all that might be required are small amounts of genetic tweaks to reach negligible senescence.
It is also known that another mammal, the Bowhead whale, can reach 200+ and has possibly a theoretical lifespan of about 250 years!
Why the Bowhead whale is outliving so much the other kind of whales?-melajara

Some sources say the bowhead whale might not even age.
Because the naked mole-rat is better adapted to deal with the damage. I'm sure we could get humans to live to 200, if we for 10 000 years only allowed those with the oldest (grand) grand parents to get children.-Erik
Within the mouse the neurons have the capacity, the mechanisms, to live over twice as long as the mouse itself(probably even longer than twice if not indefinitely), these are the cells that are subject to some of the highest amount of damage of all cells due to their extremely high metabolic activity. Also unlike other cells these cells can't divide to dilute the damage in daughter cells. All the defense and repair mechanisms of these neural cells also exist in each and every cell of the mouse, as the genome is shared, and since most of the other cells have lower metabolic activity the mechanisms might actually be overkill as they can handle far greater generation of damaging byproducts of metabolism than other cells actually produce, plus others cells can dilute the damage by dividing.


post on Josh Mitteldorf's blog

The thing is, that there appear to be quality control mechanisms that ensure dysfunctional mitochondria are eliminated.
“Thus, suggesting that mitochondrial dysfunction is a good enough reason for eliminating mitochondria and as Dr. Skulachev says, mitochondria follow the samurai’s law; “it’s better to die than to be wrong”.”-Mitoptosis, a Novel Mitochondrial Death Mechanism Leading Predominantly to Activation of Autophagy, 2012
We already have the sequences of animals(bowhead whale) that appear to live for multiple centuries, and that according to some do not even appear to age. As far as I know, I’ve not heard of evidence of mitosens like solutions having evolved to allow such extreme longevity. Even in mammals, afaik, humans do not have further mitochondria genes transferred to the nucleus compared to shorter lived species like bonobos or mice, the solution to extend lifespan proposed in mitosens, iirc.
For all we know the only reason mitochondria dysfunction might occur is either inheritance of sufficient mutation load from parents or age related downregulation of quality control mechanisms.-Darian S, link to source