More, more, and more

Adams GS et al. People systematically overlook subtractive changes. Nature, April 2021

A recent study showed that human beings are driven by a powerful instinct to add rather than subtract in daily problem solving. Researchers asked 1,585 participants to solve puzzles or problems where they could either add or subtract elements. Strikingly, in every single test the majority of participants chose addition over subtraction even in instances where subtraction made much more sense. For one of the puzzles, participants could either shade in squares or erase them in order to make a symmetrical pattern. Out of 94 participants, 73 added squares, 18 subtracted, and 3 simply moved around the existing squares. In another puzzle, participants were given a Lego structure and told to improve it however they liked. More than 90 percent chose to add blocks rather than remove some of them. This pattern was very consistent over many different problems. When asked to improve an essay most people lengthened it, and when asked to improve a recipe the majority added more ingredients. However, when participants were instructed or incentivized, they finally started to consider the possibility that less is more. For instance, when participants were asked to stabilize a Lego tower, they were told that completion of task will be rewarded with $1 but each new added piece during construction will cost them 10 cents. The participants then seriously considered removing pieces to solve the problem.

There are explanations for why humans might favor addition over subtraction in problem solving. While additive ideas may come to mind more quickly and easily, subtractive ideas require more cognitive effort. Numerical concepts of “more” and “higher” may be associated with the evaluative concepts of “positive” and “better” in our brains. For example, in many areas of life it may be easier to gain recognition for making something than for taking something away. This human behavior has wide-reaching implications in costly modern trends such as overburdened minds and schedules, increasing red tape in institutions, and irresponsible usage of the planet’s resources as a result of greed. Perhaps we should begin asking ourselves what we can take away before looking to see what we can add to solve our problems.

Plastics to be recycled “infinitely”

Vora N et al. Leveling the cost and carbon footprint of circular polymers that are chemically recycled to monomer. Science Advances, April 2021.

Plastics are a part of nearly every product we use. The average person in the U.S. generates about 100 kg of plastic waste per year, most of which goes straight to landfills. The invention of a new plastic called poly (diketoenamine), or PDK, could now potentially solve this global waste and energy crisis. PDK has all the convenient properties of traditional plastics without any environmental pitfalls. Unlike traditional plastics, PDKs can be recycled indefinitely with no loss in quality. The biggest problem in recycling traditional plastics is that chemicals in many plastics that make them useful are tightly bound to the monomers that stay in plastic even after it’s been recycled resulting in a new material with much lower quality. In contrast, PDK plastics solves this problem entirely since they are engineered to easily break down into individual monomers when mixed with an acid. The monomers can then be separated from any additives and the plastics can be reassembled into different shapes, textures, and colors again without any loss of quality. This process is named “chemical recycling” and requires low energy usage and has minimal carbon dioxide emissions and can be repeated indefinitely thus resulting in a completely sustainable material lifecycle.

Initial analysis showed that the best starting application for PDKs are markets in the automobile and consumer electronics industries that can make sustainable branding and savings. The long-term plan is to develop PDK plastics with a wide range of thermal and mechanical properties for applications as diverse as textiles, 3D printing, foams, and other packaging materials. In addition, scientists are looking to expand formulations by incorporating plant-based materials and other sustainable sources.

Genetic consequences of Chernobyl after 35 years

Yeager M. et al. Lack of transgenerational effects of ionizing radiation exposure from the Chernobyl accident. Science, April 2021

Morton LM et al. Radiation-related genomic profile of papillary thyroid cancer after the Chernobyl accident. Science, April 2021

The effects of radiation on human health have been investigated since the atomic bombings of Hiroshima and Nagasaki in World War 2 and the nuclear accidents in Chernobyl, Ukraine and Fukushima, Japan. April 26^th marks 35 years since the world’s worst nuclear power disaster in Chernobyl, where a reactor in a nuclear power plant exploded and released huge amounts of radioactive material into the environment. The Chernobyl accident killed 31 people immediately, and thousands more died over the years from radiation-linked illnesses such as cancer. Millions of acres of farmland in Europe were contaminated. The true toll of Chernobyl's meltdown remains controversial and simply unknown. Recently, international teams of researchers have looked closely at the genetic damage of the Chernobyl exposures in two separate studies.

The first study investigated whether radiation exposure results in genetic changes that can be passed from parent to offspring. Researchers analyzed the complete genomes of 130 people born between 1987 and 2002 and their 105 parents who had worked in Chernobyl during the accident or lived close to the accident site. Each parent was evaluated for protracted exposure to ionizing radiation. Whole-genome sequencing revealed that there was no evidence of an increase in the number or types of de novo (newly arising) mutations in their children born between 46 weeks and 15 years after the accident. These results suggest that radiation exposure surprisingly does not harm future generations at the genetic level.

The second study aimed to profile the genetic changes in thyroid cancers that developed in 359 people that were exposed as children or in utero to ionizing radiation from radioactive iodine during the accident and in 81 unexposed individuals born more than nine months after the accident. An increased risk of thyroid cancer has been one of the most prominent adverse health effects of radioactive iodine. In high doses, radioactive iodine kills thyroid cells and can actually be used as a treatment for thyroid cancer however the radiation from Chernobyl wasn’t strong enough to kill cells. Instead, the next-generation sequencing data showed that the months-long exposure to lower doses had mutated genes by breaking the double strands of DNA and ultimately resulted in tumors. The association between double strand breaks and radiation exposure was more pronounced for those younger at exposure. 

Taken together, these two studies not only give us new insights into the long-term effects of radiation, but they also highlight how important long-term investments in scientific research and proper data collection are. In 1980s, scientists didn’t have the genomics technologies to understand the molecular effects of radiation, but they meticulously collected tissue samples, monitored radiation, and interviewed people over many decades. Investment in long-term scientific research always pays off.