No link found between gender and performance in physics courses

Dew et al. Gendered performance differences in introductory physics: A study from a large land-grant university. Physical Review Physics Education Research, February 2021.

A new study discredits the stereotype that male students perform better than female students in science, more specifically in physics. Researchers from Texas A&M University analyzed the grades of more than 10,000 students enrolled in four introductory physics courses over a decade-long period and found no evidence that male students consistently outperformed female students in these courses. Their analyses showed that exam success and final grades were largely independent of student gender. In addition to multiple statistical analyses of course-level data, researchers distributed questionnaires to students to see how the results aligned with student perceptions. Interestingly, student responses showed that female students had lower perceptions of their performance than their male classmates. The only class where female students perceived their performance as equal to their male classmates was algebra-based mechanics, in which females outperformed males. This study can be another step in breaking up the preconceived notion of a societal bias based on gender in physics. Moreover, it may help to fight against gender stereotypes that negatively impact so many female students and harm women in STEM (science, technology, engineering, and math) related courses.  All students should have equal opportunities and chances for success.

Air pollution may cause chronic heart disease in children

Prunicki et al. Air pollution exposure is linked with methylation of immunoregulatory genes, altered immune cell profiles, and increased blood pressure in children. Scientific Reports, February 2021.

Exposure to air pollution has been linked to various diseases in adults, but no study had yet extensively investigated its long-term impacts on children. A new study suggests that children exposed to air pollution, such as wildfire smoke and car exhaust, for as little as one day may become more prone to heart disease in adulthood. Researchers investigated air pollution’s effects at the single-cell level in a group of 221 school-aged children (6–8 years). They focused on Fresno, California, a city with some of the country's highest air pollution levels due to industrial agriculture and wildfires. Using a combination of continuous daily pollutant concentrations measured at central air monitoring stations in Fresno, daily concentrations from periodic spatial sampling, and meteorological and geophysical data, the research team estimated average air pollution exposures for 1 day, 1 week, and 1, 3, 6, and 12 months prior to each participant visit. When combined with health and demographics questionnaires, blood pressure readings, and blood samples, the data showed that polluted air can alter gene regulation in cardiovascular and immune systems of children in a way that can impact long-term health. In particular, exposure to fine particles, carbon monoxide, and ozone over time is linked to increased DNA methylation, a form of epigenetic alteration of DNA molecules that can change their activity without changing their sequence. This inheritable change in gene expression may be passed down to future generations. Researchers also found that air pollution exposure leads to an increase in monocytes, white blood cells that play a key role in the buildup of plaques in arteries and could possibly predispose children to heart disease in adulthood. According to the World Health Organization, air pollution is one of the leading causes of death in children. Children typically breath faster than adults, making them more susceptible to health problems by rapidly inhaling low quality air. With air quality deteriorating globally, we all need to be more careful and conscientious to protect kids from air pollution.

Sleep memories

Clawson et al. Causal role for sleep-dependent reactivation of learning-activated sensory ensembles for fear memory consolidation. Nature Communications, February 2021.

Sleep is very critical for brain functions. Inadequate sleep can impair our abilities to concentrate, think clearly, and process memories. Past studies showed that regions of the brain that are highly active during intensive learning surprisingly show more activity during sleep. However, which biological purpose this “reactivation” of memories during sleep serves remains unclear. To address this question, researchers studied how memories associated with a specific sensory event are formed and stored in mice. They specifically examined how a fearful memory formed in relation to a particular visual stimulus in the brain. By focusing on a specific set of neurons in the primary visual cortex, researchers were able to create a visual memory test. When they ran this test in various conditions, the mice with regular sleep learned to fear the specific stimuli that had been paired with a foot shock. However, the mice with disrupted sleep had no fear association with the visual stimulus. These sleep-deprived mice seemed to process the fact that they should be afraid, but there may have been a lost connection regarding what they were supposed to be afraid of. These observations suggest that sleep-associated reactivation of the neurons encoding that stimulus is required for them to make an accurate fear association with a visual stimulus. These findings have important implications for anxiety and post-traumatic stress disorders. In the absence of sleep, the brain seems to manage processing the fact that we should experience emotions, but we may be unable to link those emotions to exact causes accurately. That specification process may be one that goes awry with such anxiety-related disorders.