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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 Galaxy1, with properties suggesting neutron star origins2,3. However, unlike pulsars, FRBs typically show minimal variability in their linear polarization position angle (PA) curves4. Even when marked PA evolution is present, their curves deviate significantly from the canonical shape predicted by the rotating vector model (RVM) of pulsars5. 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 origins6, 7–8 over models involving distant shocks9, 10–11, echoing similar conclusions drawn from tempo-polarimetric studies of some repeating FRBs12,13. 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]