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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]

We present an extensive contemporaneous X-ray and radio campaign performed on the repeating fast radio burst (FRB) source FRB 20220912A for 8 weeks immediately following the source's detection by CHIME/FRB. This includes X-ray data from XMM-Newton, NICER, and Swift, and radio detections of FRB 20220912A from CHIME/Pulsar and Effelsberg. We detect no significant X-ray emission at the time of 30 radio bursts with upper limits on a 0.5–10.0 keV X-ray fluence of (1.5–14.5) × 10−10 erg cm−2 (99.7% credible interval, unabsorbed) on a timescale of 100 ms. Translated into a fluence ratio η x/r = F X-ray/ F radio, this corresponds to η x/r < 7 × 106. For persistent emission from the location of FRB 20220912A, we derive a 99.7% 0.5–10.0 keV isotropic flux limit of 8.8 × 10−15 erg cm−2 s−1 (unabsorbed) or an isotropic luminosity limit of 1.4 × 1041 erg s−1 at a distance of 362.4 Mpc. We derive a hierarchical extension to the standard Bayesian treatment of low-count and background-contaminated X-ray data, which allows the robust combination of multiple observations. This methodology allows us to place the best (lowest) 99.7% credible interval upper limit on an FRB η x/r to date, η x/r < 2 × 106, assuming that all 30 detected radio bursts are associated with X-ray bursts with the same fluence ratio. If we instead adopt an X-ray spectrum similar to the X-ray burst observed contemporaneously with FRB-like emission from the Galactic magnetar SGR 1935+2154 detected on 2020 April 28, we derive a 99.7% credible interval upper limit on η x/r of 8 × 105, which is only 3 times the observed value of η x/r for SGR 1935+2154. [ABSTRACT FROM AUTHOR]

The Canadian Hydrogen Mapping Experiment (CHIME) is a radio telescope located in British Columbia, Canada. The large field of view allows CHIME/FRB to be an exceptional pulsar and rotating radio transient (RRAT) finding machine, despite saving only the metadata of incoming Galactic events. We have developed a pipeline to search for pulsar/RRAT candidates using density-based spatial clustering of applications with noise (dbscan), a clustering algorithm. Follow-up observations are then scheduled with the more sensitive CHIME/Pulsar instrument capable of near-daily high-time resolution spectra observations. We have developed the CHIME/Pulsar Single Pulse Pipeline to automate the processing of CHIME/Pulsar search-mode data. We report the discovery of 21 new Galactic sources, with 14 RRATs, 6 isolated long-period pulsars, and 1 binary system. Owing to CHIME/Pulsar's observations, we have obtained timing solutions for 8 of the 14 RRATs along with all the regular pulsars and the binary system. Notably, we report that the binary system is in a long orbit of 412 d with a minimum companion mass of 0.1303 solar masses and no evidence of an optical companion within 10″ of the pulsar position. This highlights that working synergistically with CHIME/FRB's large survey volume CHIME/Pulsar can obtain arc second localizations for low-burst rate RRATs through pulsar timing. We find that the properties of our newly discovered RRATs are consistent with those of the presently known population. They tend to have lower burst rates than those found in previous surveys, which is likely due to survey bias rather than the underlying population. [ABSTRACT FROM AUTHOR]

The CHIME/FRB project has detected hundreds of fast radio bursts (FRBs), providing an unparalleled population to statistically probe the foreground media that they illuminate. One such foreground medium is the ionized halo of the Milky Way (MW). We estimate the total Galactic electron column density from FRB dispersion measures (DMs) as a function of Galactic latitude using four different estimators, including ones that assume spherical symmetry of the ionized MW halo and ones that imply more latitudinal variation in density. Our observation-based constraints of the total Galactic DM contribution for ∣ b ∣ ≥ 30°, depending on the Galactic latitude and selected model, span 87.8–141 pc cm−3. This constraint implies upper limits on the MW halo DM contribution that range over 52–111 pc cm−3. We discuss the viability of various gas density profiles for the MW halo that have been used to estimate the halo's contribution to DMs of extragalactic sources. Several models overestimate the DM contribution, especially when assuming higher halo gas masses (∼3.5 × 1012 M ⊙). Some halo models predict a higher MW halo DM contribution than can be supported by our observations unless the effect of feedback is increased within them, highlighting the impact of feedback processes in galaxy formation. [ABSTRACT FROM AUTHOR]

Studies have documented associations between traumatic brain injury (TBI) and mental disorders. The relationship between psychopathic personality and TBI remains poorly understood, though both are associated with similar characteristics (e.g., low empathy, aggression, disturbances in social/moral behavior). Yet, it is not clear whether assessment of psychopathic features is influenced by presence versus absence of TBI, and which aspects of TBI may be associated with psychopathic traits. This study examined the psychopathy-TBI association in justice-involved women (N = 341) with structural equation modeling. We tested if measurement invariance of psychopathic traits was evident among those with versus without TBI and which TBI variables (number, severity, age at first TBI) predicted psychopathic features in conjunction with symptoms of psychopathology, IQ, and age. Results provided evidence of measurement invariance, and more women with TBI, compared to those without, met criteria for psychopathy. Younger age of TBI and TBI severity predicted interpersonal-affective psychopathic features. [ABSTRACT FROM AUTHOR]

To date, very few studies have explored the association between psychopathic traits and risky sexual behavior (RSB) among women. Here, we investigated this relationship in a sample of 137 incarcerated women. Psychopathic traits were assessed via the Hare Psychopathy Checklist–Revised (PCL-R) and lifetime RSB measures, including number of lifetime sexual partners, frequency of engaging in sexual intercourse while intoxicated, and frequency of forgoing protection (e.g., condom usage) during sexual intercourse, were assessed through self-report. PCL-R Facet 3 scores (assessing lifestyle psychopathic traits) were associated with an increased frequency of engaging in sexual intercourse while intoxicated. In addition, women scoring high on the PCL-R were more likely to engage in sexual intercourse while intoxicated compared with a previously collected sample of men scoring high on the PCL-R. The results obtained in the current study help improve our understanding of the association between psychopathic traits and RSB among women. [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]

Objective: Pediatric cancer and cancer-related treatments may disrupt brain development and place survivors at risk for long term problems with cognitive functions. Processing efficiency has been operationalized as a nuanced cognitive skill that reflects both processing speed (PS) and working memory (WM) abilities and is sensitive to neurobiological disruption. Pediatric cancer survivors are at risk for processing efficiency deficits; however, a thorough characterization of processing efficiency skills across pediatric primary central nervous system (CNS) tumor and non-CNS cancer survivors has not yet been reported. Participants and Methods: Participants were selected from a mixed retrospective clinical database of pediatric cancer survivors (Total n=160; primary CNS tumor n=33; Non-CNS n=127). Univariate analyses were conducted to examine differences in processing efficiency mean scores (t-tests) and percent impairment (scores >1 SD below mean; chi-squared tests) between the total sample and normative sample, and across groups (CNS vs. Non-CNS). Multiple linear regressions were utilized to evaluate the relationships between additional risk factors, including biological sex, age at diagnosis, time since treatment, and socioeconomic status, and processing efficiency outcomes. Results: The total sample obtained lower scores on WM (M=90.83, SD=13.35) and PS (M=88.86, SD=14.38) measures than normative samples (M=100, SD=15), p < 0.001. Greater percentage of pediatric cancer survivors demonstrated impairment across all processing efficiency measures (24.8-38.1%) than normative samples (15.9%), p < 0.001. Regarding group differences, the CNS group obtained lower mean WM (M=84.85, SD =11.77) and PS (M=80, SD=14.18) scores than the Non-CNS group (WM M=92.39, SD=13.32; PS M=91.16, SD=13.56), p < 0.001. Rates of impairment between groups only differed for PS scores, with 63.6% of the CNS group and 31.5% of the non-CNS group demonstrating impairment, p < 0.001. Primary CNS tumor cancer type and male biological sex emerged as the only significant risk factors that predicted processing efficiency skills, with male sex predicting lower scores on PS (ß=8.91 p<.001) and semantic fluency (ß=7.59, p=.007). Conclusions: These findings indicate that both pediatric primary CNS tumor and non-CNS cancer survivors exhibit substantial weaknesses in processing efficiency skills after treatment. While both groups demonstrated deficits compared to normative samples, the CNS group was more susceptible to PS impairments than non-CNS group. A basic initial study of the relationships between risk factors and processing efficiency skills revealed that primary CNS cancer was a predictor of lower performance on working memory and processing speed measures, while male biological sex was a significant risk factor for worse performance on processing speed and semantic fluency measures. Continued focus on the construct of processing efficiency in pediatric cancer survivors is warranted. Applying a standardized approach to assessing and communicating this nuanced cognitive skill could contribute to advancing both clinical practice and outcomes research of pediatric cancer survivors. [ABSTRACT FROM AUTHOR]

Methyl parathion (MP) was used illegally to spray homes for insect control over approximately an 8-yr period. In an attempt to determine if there were any adverse health effects from this, health-screening evaluations were performed on 353 individuals living in homes that were illegally sprayed. The average subject spent 15.5 h a day in the home. Subjects from homes with high levels of MP (exposure group) were compared to controls that lived in homes with minimal or no MP. Subjects were aware of the levels of MP found in their homes and recall bias was likely. There were no significant differences in the symptoms reported or by the physician assessment of subacute or chronic toxicity between those in the exposure group and controls. No significant differences were found in growth and developmental evaluations. Three subjects were identified who most likely suffered acute toxicity from the initial exposure and were not appropriately diagnosed and treated. Cholinesterase determinations also did not differ between those in the exposure group and controls. When subjects from the exposure group were stratified by the level of MP in their home, those from homes with the highest levels appeared to have an increased likelihood of subacute toxicity and reported an increased number of neuropsychiatric symptoms (OR 2 for both evaluations). [ABSTRACT FROM AUTHOR]

Infrared spectroscopic studies of ultraviolet (UV) irradiated, water-rich, cosmic ice analogs containing small polycyclic aromatic hydrocarbons (PAHs) are described. The irradiation studies of anthracene:H2O, pyrene:H2O, and benzo[ghi]perylene:H2O ices (14 K) at various concentrations reported by Bouwman et al. are extended. While aromatic alcohols and ketones have been reported in residues after irradiated PAH:H2O ices were warmed to 270 K, it was not known if they formed during ice irradiation or during warm-up when reactants interact as H2O sublimes. Recent work has shown that they form in low temperature ice. Using DFT computed IR spectra to identify photoproducts and PAH cations, we tentatively identify the production of specific alcohols [PAH(OH)n] and quinones [PAH(O)n] for all PAH:H2O ices considered here. Little evidence is found for hydrogenation at 14 K, consistent with the findings of Gudipati & Yang. Addition of O and OH to the parent PAH is the dominant photochemical reaction, but PAH erosion to smaller PAHs (producing CO2 and H2CO) is also important. DFT spectra are used to assess the contribution of PAH-related species to interstellar absorption features from 5 to 9 μm. The case is made that PAH cations are important contributors to the C2 component and PAH(OH)n and PAH(O)n to the C5 component described by Boogert et al. Thus, interstellar ices should contain neutral and ionized PAHs, alcohols, ketones and quinones at the ∼2%-4% level relative to H2O. PAHs, their photoproducts, and ion-mediated processes should therefore be considered when modeling interstellar ice processes. [ABSTRACT FROM AUTHOR]