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The C–H bonds of methane are generally more kinetically inert than those of other hydrocarbons, reaction solvents, and methane functionalization products. Thus, developing strategies to achieve selective functionalization of CH₄ remains a major challenge. Here, we report transition metal–catalyzed C–H borylation of methane with bis-pinacolborane (B₂pin₂) in cyclohexane solvent at 150°C under 2800 to 3500 kilopascals of methane pressure. Iridium, rhodium, and ruthenium complexes all catalyze the reaction. Formation of mono- versus diborylated methane is tunable as a function of catalyst, with the ruthenium complex providing the highest ratio of CH₃Bpin to CH₂(Bpin)₂. Despite the high relative concentration of cyclohexane, minimal quantities of borylated cyclohexane products are observed. Furthermore, all three metal complexes catalyze borylation of methane with >3.5:1 selectivity over ethane.

There is a well-documented relationship between academic match and bachelor’s degree completion; students who undermatch are less likely to complete a BA than those who match or overmatch, net of academic qualifications and demographic characteristics. Little is known, however, about whether this association has changed over time. I argue that recent trends in U.S. higher education may have altered this association. Thus, while prior research has documented gaps in outcomes between undermatched, matched, and overmatched students, it is important to understand how these gaps may be evolving. The present study uses nationally representative data from three cohorts of first-time college students—students who began college in 1995, 2003, and 2011—to examine this question. Findings show that, in some ways, the association between academic match and BA completion has remained stable over time; across all three cohorts, undermatched students are less likely to graduate than matched and overmatched students, after controlling for academic qualifications and demographic characteristics. In other ways, the association may be evolving; overall, overmatched students’ odds of graduation have increased over time, while matched and undermatched students’ have not. There are multiple possible explanations for this, including the fact that graduation rates in recent years have become increasingly stratified by college selectivity. The study concludes with recommendations for policy and practice, as well as suggestions for future research.

SuperAgers are adults over the age of 80 with superior episodic memory performance and at least average-for-age performance in non-episodic memory domains. This study further characterized the neuropsychological profile of SuperAgers compared to average-for-age episodic memory peers to determine potential cognitive mechanisms contributing to their superior episodic memory performance. Retrospective analysis of neuropsychological test data from 56 SuperAgers and 23 similar-age peers with average episodic memory was conducted. Independent sample -tests evaluated between-group differences in neuropsychological scores. Multiple linear regression determined the influence of non-episodic memory function on episodic memory scores across participants. As a group, SuperAgers had better scores than their average memory peers on measures of attention, working memory, naming, and speeded set shifting. Scores on tests of processing speed, visuospatial function, verbal fluency, response inhibition, and abstract reasoning did not differ. On an individual level, there was variability among SuperAgers with regard to non-episodic memory performance, with some performing above average-for-age across cognitive domains while others performed in the average-for-age range on non-memory tests. Across all participants, attention and executive function scores explained 20.4% of the variance in episodic memory scores. As a group, SuperAgers outperformed their average memory peers in multiple cognitive domains, however, there was considerable intragroup variability suggesting that SuperAgers' episodic memory strength is not simply related to globally superior cognitive functioning. Attention and executive function performance explained approximately one-fifth of the variance in episodic memory and maybe areas to target with cognitive interventions.

Objectives. To determine the impact of city-level cannabis decriminalization and medical marijuana laws (MMLs) on fatal traffic crashes in US cities. Methods. Using a census of fatal traffic crashes from the 2010 to 2017 Fatality Analysis Reporting System, we examined MMLs and cannabis decriminalization on fatal crashes by age and sex of driver. We used a Poisson difference-in-differences approach, exploiting temporal and geographic variation in marijuana decriminalization laws. Results. Cities experienced a 13% increase in fatal crashes involving 15- to 24-year-old male drivers following decriminalization (incidence rate ratio = 1.125; 95% confidence interval = 1.014, 1.249). This effect was immediate and strongest on weekend nights. We found no effect on female drivers or older males. Conversely, we found that MMLs were associated with fewer fatal crashes for both males and females, which was most pronounced in 15- to 24-year-old drivers. Conclusions. Unlike MMLs, which are associated with fewer fatal crashes, cities experienced a relative increase in fatal crashes involving young male drivers following marijuana decriminalization. Public Health Implications. MMLs stipulate consumption occurs at home, whereas decriminalization only lessens the penalty for marijuana possession. Therefore, travel incentives of such laws have heterogeneous effects on traffic safety.

Fast radio bursts (FRBs) last for milliseconds and arrive at Earth from cosmological distances. Although their origins and emission mechanisms are unknown, their signals bear similarities with the much less luminous radio emission generated by pulsars within our Miky Way Galaxy 1 , with properties suggesting neutron star origins 2 , 3 . However, unlike pulsars, FRBs typically show minimal variability in their linear polarization position angle (PA) curves 4 . Even when marked PA evolution is present, their curves deviate significantly from the canonical shape predicted by the rotating vector model (RVM) of pulsars 5 . Here we report on FRB 20221022A, detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst project (CHIME/FRB) and localized to a nearby host galaxy (about 65 Mpc), MCG+14-02-011. This FRB shows a notable approximately 130° PA rotation over its about 2.5 ms burst duration, resembling the characteristic S-shaped evolution seen in many pulsars and some radio magnetars. The observed PA evolution supports magnetospheric origins 6 , 7 – 8 over models involving distant shocks 9 , 10 – 11 , echoing similar conclusions drawn from tempo-polarimetric studies of some repeating FRBs 12 , 13 . The PA evolution is well described by the RVM and, although we cannot determine the inclination and magnetic obliquity because of the unknown period or duty cycle of the source, we exclude very short-period pulsars (for example, recycled millisecond pulsars) as the progenitor. FRB 20221022A, detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst project, shows a pronounced change in polarization during the burst, providing important clues into the nature of the source.

We evaluate whether health insurer aggregate prescription drug expenditures change after the legalisation of medicinal cannabis using U.S. health insurer financial filings reported to state insurance regulators and compiled by the National Association of Insurance Commissioners for private health insurers from 2010 to 2018. We analyse this question for health insurers in the individual market, which includes plans sold on the Affordable Care Act exchanges, the small group market, which consists of fully insured plans sold to employers with fewer than 50 employees, and the large group market, which consists of fully insured plans sold to employers with more than 50 employees. For all three markets, the treatment effects are not significant. Thus, we find no impact of medical cannabis legalisation on health insurer prescription drug expenditures, despite the potential disruption to the health insurance market. Had legalisation increased prescription drug expenditures, the increases in cost would have been borne by enrollees, which is troubling since healthcare costs are rising faster than inflation.

For 165 million nonelderly Americans, employers provide health insurance either by purchasing a fully insured plan or through self-insurance. By self-insuring, employers bear the financial risk for enrollees' health care spending and are accountable for plan management, either directly or by contracting with a third-party administrator. Using National Association of Insurance Commissioners data, we demonstrate that insurers are deeply entrenched in the provision of administrative services only (ASO) contracts for self-insured employers. In 2022, insurers administered to nearly four times as many ASO enrollees as they covered in fully insured plans, with fifty-six insurer-based ASO contractors providing services for 118 million enrollees. The largest ASO contractors-CVS Group, Cigna Health Group, and Elevance Health Inc. Group-collectively served more than seventy million ASO enrollees and demonstrated less variable and stronger profitability relative to other ASO contractors. This study expands understanding of this increasingly important market for employer-sponsored insurance.

The Northwestern University SuperAging Program studies a rare cohort of individuals over age 80 with episodic memory ability at least as good as middle-age adults to determine what factors contribute to their elite memory performance. As psychological well-being is positively correlated with cognitive performance in older adults, the present study examined whether aspects of psychological well-being distinguish cognitive SuperAgers from their cognitively average-for-age, same-age peers. Thirty-one SuperAgers and 19 cognitively average-for-age peers completed the Ryff 42-item Psychological Well-Being questionnaire, comprised of 6 subscales: Autonomy, Positive Relations with Others, Environmental Mastery, Personal Growth, Purpose in Life, and Self-Acceptance. The groups did not differ on demographic factors, including estimated premorbid intelligence. Consistent with inclusion criteria, SuperAgers had better episodic memory scores. Compared to cognitively average-for-age peers, SuperAgers endorsed greater levels of Positive Relations with Others. The groups did not differ on other PWB-42 subscales. While SuperAgers and their cognitively average-for-age peers reported similarly high levels of psychological well-being across multiple dimensions, SuperAgers endorsed greater levels of positive social relationships. This psychological feature could conceivably have a biological relationship to the greater thickness of the anterior cingulate gyrus and higher density of von Economo neurons previously reported in SuperAgers.

Objective:In research, and particularly clinical trials, it is important to identify persons at high risk for developing Alzheimer’s Disease (AD), such as those with Mild Cognitive Impairment (MCI). However, not all persons with this diagnosis have a high risk of AD as MCI can be broken down further into amnestic MCI (aMCI), who have a high risk specifically for AD, and non-amnestic MCI (naMCI), who are predominantly at risk for other dementias. People with aMCI largely differ from healthy controls and naMCI on memory tasks as it is the hallmark criteria for an amnestic diagnosis. Given the growing use of the NIH Toolbox Cognition battery in research trials, this project investigated which Toolbox Cognition measures best differentiated aMCI from naMCI and in comparison to persons with normal cognition.Participants and Methods:A retrospective data analysis was conducted investigating performance on NIH Toolbox Cognition tasks among 199 participants enrolled in the Michigan Alzheimer’s Disease Research Center. All participants were over age 50 (51-89 years, M=70.64) and had a diagnosis of aMCI (N=74), naMCI (N=24), or Normal Cognition (N=101). Potential demographic differences were investigated using chi-square and ANOVAs. Repeated measure general linear model was used to look at potential group differences in Toolbox Cognition performance, covarying for age which was statistically different in aMCI versus Normal participants. Linear regression was used to determine which cognitive abilities, as measured by the Uniform Data Set-3 (UDS3), might contribute to Toolbox differences noted in naMCI versus aMCI groups.Results:As expected, aMCI had lower Toolbox memory scores compared to naMCI (p=0.007) and Normals (p<0.001). Interestingly, naMCI had lower Oral Reading scores than both aMCI (p=0.008) and Normals (p<0.001). There were no other Toolbox performance differences between the MCI groups. 19.4% of the variance in Oral Reading scores was explained by performance on the following UDS3 measures: Benson delayed recall (inverse relationship) and backward digit span and phonemic fluency (positive relationship).Conclusions:In this study, Toolbox Picture Sequence Memory and Oral Reading scores differentiated aMCI and naMCI groups. While the difference in memory was expected, it was surprising that the naMCI group performed worse than the aMCI and normal groups on the Toolbox Oral Reading task, a task presumed to reflect Crystalized abilities resistive to cognitive decline. Results suggest that Oral Reading is primarily positively associated with working memory and executive tasks from the UDS3, but negatively associated with visual memory. It is possible that the Oral Reading subtest is sensitive to domains of deficit aside from memory that can best distinguish aMCI from naMCI. A better understanding of the underlying features in the Oral Reading task will assist in better characterizing deficit patterns seen in naMCI, making selection of aMCI participants more effective in clinical trials.

Validated computerized assessments for cognitive functioning are crucial for older individuals and those at risk of cognitive decline. The National Institutes of Health (NIH) Toolbox Cognition Battery (NIHTB-CB) exhibits good construct validity but requires validation in diverse populations and for adults aged 85+. This study uses data from the Assessing Reliable Measurement in Alzheimer's Disease and cognitive Aging study to explore differences in the factor structure of the NIHTB-CB for adults 85 and older, Black participants versus White participants, and those diagnosed as amnestic Mild Cognitive Impairment (aMCI) vs cognitively normal (CN). Subtests from the NACC UDS-3 and NIHTB-CB were administered to 503 community-dwelling Black and White adults ages 55-99 (367 CN; 136 aMCI). Confirmatory factor analyses were used to investigate the original factor structure of NIHTB-CB that forms the basis for NIHTB-CD Index factor scores. Factor analyses for all participants and some participant subsets (aMCI, White, 85+) substantiated the two anticipated factors (Fluid and Crystallized). However, while Black aMCI participants had the expected two-factor structure, for Black CN participants, the List Sorting Working Memory and Picture Sequence tests loaded on the Crystallized factor. Findings provide psychometric support for the NIHTB-CB. Differences in factor structure between Black CN individuals and Black aMCI individuals suggest potential instability across levels of cognitive impairment. Future research should explore changes in NIHTB-CB across diagnoses in different populations.