Sunday, July 31, 2011

Consciousness only exists as a human construct

It is quite possible that consciousness may not be an objectively definable phenomenon, but rather a convenient illusion created by humans to provide a context for understanding reality. While machines such as CT scans and MRIs measure human cognition, it may not be possible to measure the direct qualities of consciousness. Philosophers and others have pointed out that consciousness may be a subjective quality arising from the operation of the brain.

One reason that a more detailed look at consciousness may be interesting is in the contemplation of non-human intelligence. Given the aspect of subjective qualia surrounding the label consciousness, it might be insulting to non-human intelligence to be referred to as having consciousness, the more objective attribute ‘self-aware’ being preferable. If human consciousness does not exist, non-human consciousness would be even less likely to exist.

Sunday, July 24, 2011

Longevity genomics paper retracted

On July 22, 2011, a high-profile longevity genomics paper published in Science in July 2010 was retracted. The paper, ‘Genetic Signatures of Exceptional Longevity in Humans,’ was the work of Thomas Perls and Paola Sebastiani (Boston University). The initial study had been revised per editorial concerns that arose last year, but has now been retracted possibly due to issues related to the replicatability the findings.

The revised study results were presented by the team at the American Aging Association meeting in June 2011. These data featured nine single SNP associations (versus two previously), and linked 281 SNPs to signatures for exceptional longevity (versus 180 SNPs previously). The overall conclusion remained unchanged - that

centenarians, while having the same disease mutational profiles as non-centenarians, have other specific aspects to their genetic profiles which indicate a signature for exceptional longevity

Sunday, July 17, 2011

Towards an epistemology of citizen science

Now that citizen science in the health domain is becoming more established, it is relevant to scale it up to tackle larger projects. Several things can be done such as the definition and introduction of liability and oversight models that would be the analogue of the traditional IRB (institutional review board), and the professionalization of participant roles in the study ecosystem such as that of the study manager.

A more subtle issue is to develop an epistemology of citizen science. This would provide a structure and context for exploring the knowledge that is derived from citizen science. One question is whether new kinds of knowledge are being formed through group collaborations such as wikipedia and health social networks. Another question is characterizing the differences (if any) in the types of knowledge generated by traditional medicine, self-experimentation, and health collaboration communities.

Sunday, July 10, 2011

Practical applications in anti-aging

One nice aspect of aging conferences is that there are usually a few gems of information that can be applied immediately in humans. Several actionable solutions were highlighted at the 40th annual meeting of the American Aging Association held June 3-6, 2011 in Raleigh NC USA (conference summary), in the areas of pharmaceuticals, nutrition, lifestyle, exercise, and fasting.

In summary, hypertension drug losartan may help sarcopenia, the healthier fats and antioxidants in walnuts, blueberries, and nectarines may facilitate health, hot tubs may reduce blood pressure, endurance exercise is better for older adults, and protein restriction may be the best form of caloric restriction.
In detail...
  • In pharmaceuticals, the prescription drug losartan (an angiotensin receptor blocker) is typically used to treat hypertension and high blood pressure. It may also have anti-aging benefits in combating sarcopenia and frailty by improving muscle remodeling and grip strength.
  • In nutrition, recommendations were for walnuts, blueberries, and nectarines. Walnuts are good because they are the only nut containing a significant amount of alpha-linolenic acid (ALA), and because they are mainly composed of polyunsaturated fatty acids (PUFA, both omega-3 and omega-6) rather than monounsaturated fatty acids (MUFA), as most other nuts. Blueberries continue to be an important suggestion for anti-aging. They contain anthocyanins, antioxidants which may prevent inflammation and help to improve brain signals and memory function. The 2011 Blueberry Health Study reported that individual cognitive performance improved 1% over a one year period from consuming one half cup to two cups of blueberries per day. Necatrines (and acai) also have antioxidant properties and have been found to reduce oxidative damage and improve longevity in Drosophila melanogaster (Boyd, Free Radic Biol Med, 2011).
  • A lifestyle anti-aging remedy was found in nonhuman primates. Heated hydrotherapy, e.g.; jacuzzis, two times a week for 30 minutes at 39-41 degrees C, induced heat shock response (which declines with age) and increased production of heat shock proteins 70 and 90 which resulted in reduced blood pressure.
  • Exercise is always a good anti-aging improvement especially since 60% of U.S. adults over 60 have insufficient physical activity. Type II fibers (fast-twitch) are most vulnerable to aging so instead of trying to improve these, for older adults, it is better and easier to maintain Type I fibers associated with endurance exercise. For example, 70-80 year olds running 2-3 miles a few times a week had the glucoregulation profiles of sedentary adults in their 20s.
  • Fasting, especially amino acid (e.g.; protein) deprivation, before chemotherapy and surgery was found to help in reducing injurious impact.

Sunday, July 03, 2011

World supercomputing capability more than triples

In a breath of good news for Japan this year, RIKEN's supercomputer "K Computer" vaulted to the top slot in world supercomputing in June 2011 as tracked by Top 500 Supercomputer Sites.

Remarkably, capability more than tripled to over 8 petaflops per second (8 quadrillion calculations per second, measured as the Maximal LINPACK performance achieved), after supercomputer performance had been asymptoting at close to 1 pf and 2 pfs for the last three years (Figure 1). China's Tianhe-1A at the National Supercomputing Center in Tianjin was in second place, and the US's Jaguar Cray at Oak Ridge National Lab in third.

The capacity tripling constitutes obvious potential benefits to scientific computing, the realm of applications for which supercomputers are used. It is hoped that these kinds of quantitative changes may eventually lead to qualitative changes in the way other problems are investigated, for example how the brain works.

Figure 1. Source: Top 500 Supercomputer Sites