TL;DR -- Spreading Cash Around the Developing World

Science, Feb. 24, 2012 -- "One-time Transfers of Cash or Capital Have Long-Lasting Effects on Microenterprises in Sri Lanka," Suresh de Mel, David McKenzie, & Christopher Woodruff.

International development and philanthropy have long been a big interest of mine.  But often practices in these areas are driven more by emotion and intuition than by sound research.

This study examined effects of granting small amounts, either in direct cash or in equivalent resources, to small business owners (in which the owner was the only employee) in Sri Lanka.  This is not microfinance, as practiced by Kiva or the Grameen Bank, but is similar to the approach taken by GiveDirectly.  However, the effects of this strategy, and especially the long-term effects, have been poorly understood; does an infusion of cash actually contribute to the success of the business and the survival of the business owner?

Five years after the researchers initially randomly distributed large ($200 equivalent) or small ($100 equivalent) amounts to small business owners, they returned to evaluate the survival and the financial health of the businesses.  What they found is that those who received initial grants did better in the long run -- they were more likely to still be in business, and their businesses were more profitable, as compared to control businesses ...but only for men.  For women, those who received grants fared no better (and, in fact, numerically worse) than those who had not received grants.

This is unsettling news.  In fact, many organizations, such as Grameen, target their approaches based partly on gender, focusing on helping out women over men.  This research suggests that, despite good intentions, this practice may be ineffective.  But why were no benefits found for women?  This study can't fully answer that question, but the authors speculate that many of the women redirected the funds (or cashed out the resources) to their households, instead of investing in their businesses.  This makes sense, considering that the businesses run by women were only about half as profitable as those run by men; the short-term gains may have overridden any long-term planning.  Factors other than gender, such as base profitability, may interact with the intervention to determine success.

Of course, there are limitations to this research.  The outcome measures were exclusively economic, but it's possible that the women who received the grants got some benefit to other measures, such as health.  It's also not clear how well these results would generalize to other regions.  Is there something specific to the cultural or economic environments of Sri Lanka that lead to this gender disparity?  But on the other hand, it's also very heartening to see that such a simple intervention can lead to durable change.

Suresh de Mel, David McKenzie, Christopher Woodruff (2012). One-time Transfers of Cash or Capital Have Long-Lasting Effects on Microenterprises in Sri Lanka Science DOI: 10.1126/science.1212973

Two on Two

There are very few things that are a surety in life, but one is this: everybody poops.  So what do psychologists have to say about this most basic of functions?  In the latest issue of The Psychologist, Nick Haslam takes us on a whirlwind tour of psychological theory and research into human excretion, from its presence in the symptomatology of various mental disorders to its role in social relations and gender roles.  Unfortunately, this is a topic that has been understudied in psychology, so the literature is kind of scant and disconnected.  However, ESPN happens to have a more focused look into the same topic that reveals both the physiology, as well as the sociology, of crapping one's pants.  A taste (poor choice of words):

The sphincter has the final say in these matters, and it is controlled by a unique double ring of muscle tissue that acts like a clip around the bottom of an inflated balloon. The outer ring is made up of voluntary muscle fiber that's under our conscious control. But the inner, more dominant ring is made up of involuntary tissue and regulated by the independent neurological gatekeeper found in the reflex centers of our spinal cord. The battle for control over the sphincter, then, is a smaller version of the constant tug of war between the sympathetic and parasympathetic divisions of the nervous system that athletes deal with when pushing their limits.

TL;DR - New Wave Antidepressants

    Scientific American, March 2012 -- "Lifting the Black Cloud," Robin Marantz Henig

    The current class of antidepressant medications, which focus on serotonin and norepinephrine, have limited effectiveness and come with a range of negative side effects.  As a result, people suffering from depression often find themselves bouncing from medication to medication, with more or less effectiveness.  Henig descibes several novel drug targets that are under investigation, and which promise a future of more choice, and better results for the depressed. 
    Ketamine is one such substance, which shows promise in speeding neural regeneration in the prefrontal cortex, reducing or reversing the neural atrophy there that often is associated with depression.  Acetylcholine is another neurotransmitter that shows promise as a target; ironically, it was one of the first systems targeted for study, but was largely ignored after serotonin showed so much promise.  Other drugs target nicotinic repceptors, and seem to be effective at stimulating neural growth in the hippocampus.  Finally, another novel research angle is to focus on inflammation, which is often associated with depression.

TL;DR - The Mesh Internet

    Scientific American, March 2012 -- "The Shadow Web," Julian Dibbell

    The internet is powerful, but a little too fragile as-is.  In an internet controlled by centralized ISPs, it becomes possible for a strong force, such as a repressive regime or a natural disaster, to bring the network down.  Dibbell describes an alternate approach to the current centralized system (which, incidentally, is much closer to its original formulation).  A mesh network relies on point users, people with a network connection, owning their own networking hardware.  Once the community of users becomes large enough, the network becomes resilient to attack or damage, such that many different nodes can go down without affecting the overall network activity.  These mesh networks are currently being developed, and are available for ~ 150$, but costs are expected to go down soon.  Dibbell points out that this would not be a replacement of the ISP model, but rather would provide a poor-man's substitute, maximizing basic access and providing competition to induce the ISPs to improve service and pricing. 

TL;DR - A Cure for HIV?

    Scientific American, March 2012 -- "Blocking HIV's Attack," Carl June & Bruce Levine

    In 2009, many headlines were grabbed by a medical story in which a man--the so-called "Berlin Patient"-- was cured of HIV after receiving a bone marrow transplant.  June and Levine explain this case, and why we're still not entirely sure what exactly happened, and elaborate on the work that they and others have done to conceptually follow up on this treatment angle. 
    HIV reproduces by hijacking the body's immune system, invading T cells and using their cellular machinery to make copies.  But some people are lucky enough to be completely resistant to HIV, not showing signs of infection despite repeated exposures.  It turns out that this is because of a genetic mutation that disables the CCR5 protein from being expressed on T cell membranes.  Without this protein, HIV lacks an entry point into the T cells, eliminating its reproductive pathway.  The Berlin Patient was a man who had both HIV and lymphoma, and so was a candidate for a bone marrow transplant.  This involves killing off his existing bone marrow with radiation and then injecting donor bone marrow (which must be a close enough genetic match that the body will accept and use it).  In this case, the bone marrow was selected to be from a donor who also happened to have the rare genetic mutation leading to an absence of CCR5 protein, and this seems to be what led to the elimination (possibly) of HIV from the recipient's system.  This is all tentative, unfortunately, due to the fact that we can't be sure whether the HIV has been eliminated, or is just hiding somewhere we can't find it, that other aspects of the treatment (such as radiation) could have killed off or reduced the HIV, and that this match was such a statistical rarity that a replication is very hard to produce.
    However, it may be possible to artificially cripple the CCR5-coding portion of the genetic code, resulting in gene therapy wherein the patient's own genetic material is extracted, altered, and reintroduced.  This might be a much more efficient, and safer, way of achieving the same sort of results.

TL;DR - Saving Energy for Later

    Scientific American, March 2012 -- "Gather the Wind," Davide Castelvecchi

    Renewable energy is definitely the future, but there are still many problems to be worked out before it can take over from fossil fuels.  One major concern is the reliability of energy sources; what happens when the wind calms, or the sun goes down?  Modern energy usage demands consistency, which renewables often lack.  Storing energy for later is the obvious way around this, and Castelvecchi reviews five different proposed solutions, each receiving ratings from an expert panel on measures of scalability, cost-effectiveness, and efficiency. 
    Pumped hydro (pumping water uphill for potential energy) and compressed air (pumping air into rock formations and caverns for later extraction) are two methods that are currently in use, and which show significant promise, though certain limitations, such as geological and geographical considerations, hinder their large-scale deployment.  Battery technology is advancing strongly, as well, though it will inevitably be costly.  I'd heard about thermal storage--storing heat in molten salt--before, though it, too has some technological hurdles to jump.  Finally, home hydrogen conversion (using small-scale systems to break down water into hydrogen at off-peak rates) is an interesting idea, though it is the one that has furthest to go before it's a practical solution. 

TL;DR - The Giants of Utah

    Scientific American, March 2012 -- "Dinosaurs of the Lost Continent," Scott Sampson

    Sampson details paleontological work that he and others have done in western North America, stretching from Alberta to Mexico, that suggests that in the Cretaceous era there were multiple (~ 17-20) species of giant (>1 ton) dinosaurs cohabitating.  Why this is surprising is because at the time, these dinosaurs were sharing a continent--Laramidia--that was significantly smaller than present-day North America, and which, based on understandings of current species, should have been too small to sustain that number of species.  As a comparison, current-day Africa is only able to sustain about 6 giant species.  Two main theories have been advanced to explain this: either the dinos were much more efficient than present-day mammals (possibly being cold-blooded, or maybe lukewarm-blooded), or the flora of the time was much more productive (the climate would have supported a hothouse environment at mid latitudes).