Did you notice that Friday the 13th falls on a Thursday this month? So does The Filtrate. Coincidence? You decide.
First, a programming note about this weekly newsletter: the summaries aren't the stories. Each contains a link to a paper or news report, and one criterion for inclusion in The Filtrate is accessibility. The links lead to full text, no paywalls. If my summaries pique your curiosity - and I hope they do - please read the associated articles.
The bizarre push to secure US academic science against "foreign" (read: Chinese) espionage continues. Republican Senator Chuck Grassley has started advocating background checks for NIH grant applicants, and Emory University has doubled down on its effort to become the poster child for bad HR management. The theory seems to be that China is somehow stealing valuable secrets from academic research labs, but basic science is notoriously difficult to commercialize, and academic scientists blab to everyone who'll listen about their projects already, so how would that even work?
On another happy note, the world now has over 7 billion people and a host of environmental and social problems. Would having fewer people help? That's been the traditional argument in development, but this paper makes a compelling case that educating the people we have is far more important than limiting the birth rate, at least in terms of the "demographic dividend" and economic measures. Among other things, that implies that the future for populous poor countries could be a lot brighter than it looks.
Speaking of family planning, what's the point of sex? Biologists have long argued that sexual reproduction serves mainly to shuffle genes around and increase diversity, which in turn makes species more resilient to changes in their environments. These folks advance a different idea: sex helps us dodge transmissible cancers. Asexual reproduction yields a population of clones, so cancer cells from one individual can infect another easily. Sexual reproduction with recombination prevents that, because cells from another individual will have distinct markers that the immune system can target.
While sex may prevent transmissible cancers, it doesn't prevent the ones that arise spontaneously. Those require treatment, and one idea is to use genetically engineered viruses to target tumors. A major challenge in this approach is getting the viruses to kill only tumor tissue, not healthy cells. This system is a clever way to accomplish that, using measles viruses with a light-activated polymerase. Shining a blue light on infected cells causes the virus to replicate, killing the cells. It would only work with tumors that can be selectively illuminated, but light should have a lot fewer side effects than toxic chemotherapies or high levels of radiation.
Light is also a great way to analyze solutions in the lab, using the classic technique of spectrophotometry. If you took a college chemistry course, you probably used a spectrophotometer to measure concentrations of various compounds, and it's a staple technique everywhere from medical labs to industrial plants. Unfortunately, spectrophotometers aren't cheap, or at least they weren't until this group decided to build one for five Euros. The paper uses both 3D printers and Lego, so if it hasn't already gone viral online it should do so soon.
It took more than a five Euro spectrophotometer to fractionate and analyze zebra sweat, but the extra effort paid off. By baiting a Ngu trap with combinations of the compounds in the equines' body odor, researchers discovered some powerful tsetse fly repellents. Smelling like a sweaty zebra doesn't sound very appealing, but it would beat catching trypanosomiasis.
That's all for this week. As always, feel free to send a tweet or an email if you want to comment on these stories, or plug something for possible inclusion in the next issue of The Filtrate.