Uncovering a population of gravitational lens galaxies with magnified standard candle SN Zwicky.

Detecting gravitationally lensed supernovae is among the biggest challenges in astronomy. It involves a combination of two very rare phenomena: catching the transient signal of a stellar explosion in a distant galaxy and observing it through a nearly perfectly aligned foreground galaxy that deflects light towards the observer. Here we describe how high-cadence optical observations with the Zwicky Transient Facility, with its unparalleled large field of view, led to the detection of a multiply imaged type Ia supernova, SN Zwicky, also known as SN 2022qmx. Magnified nearly 25-fold, the system was found thanks to the standard candle nature of type Ia supernovae. High-spatial-resolution imaging with the Keck telescope resolved four images of the supernova with very small angular separation, corresponding to an Einstein radius of only θE = 0.167″ and almost identical arrival times. The small θE and faintness of the lensing galaxy are very unusual, highlighting the importance of supernovae to fully characterize the properties of galaxy-scale gravitational lenses, including the impact of galaxy substructures.

Quality of Life Differences in Children and Adolescents With 0, 1 to 2, or 3+ Persistent Postconcussion Symptoms.

CONTEXT: Persistent postconcussion symptoms (PPCSs) are associated with lower health-related quality of life (HRQoL) in children and adolescents. Despite commonly cited criteria for PPCSs involving 3 or more complaints, many individuals experience just 1 or 2 symptoms that may still negatively affect HRQoL. OBJECTIVE: To determine differences in HRQoL between children and adolescents with 0, 1 to 2, or 3+ parent-reported persistent symptoms at 1 month postconcussion. DESIGN: Prospective cohort study. SETTING: Community practice clinics. PATIENTS OR OTHER PARTICIPANTS: Individuals aged 8 to 18 years presented for the initial visit within 3 days of a sport- or recreation-related concussion. One month later, parents or guardians reported persistent symptoms using the Rivermead Post Concussion Symptoms Questionnaire (RPQ). Individuals with complete symptom data were analyzed (n = 236/245, n = 97 females, age = 14.3 ± 2.1 years). Participants were grouped by the number of discrete RPQ symptoms reported as worse than preinjury (0, 1-2, or 3+). MAIN OUTCOME MEASURE(S): Total summary and subscale scores on the Pediatric Quality of Life Inventory (PedsQL) 23-item HRQoL inventory and 18-item Multidimensional Fatigue Scale (MDFS). RESULTS: Kruskal-Wallis rank sum tests highlighted differences in PedsQL HRQoL and MDFS total scores across symptom groups (PedsQL HRQoL: χ22 = 85.53, P < .001; MDFS: χ22 = 93.15, P < .001). Dunn post hoc analyses indicated all 3 groups were statistically significantly different from each other (P < .001). The median (interquartile range) values for the Peds QL Inventory HRQoL totals were 93.5 (84.2-98.8) for those with 0 symptoms; 84.8 (73.9-92.4) for those with 1 to 2 symptoms; and 70.7 (58.7-78.0) for those with 3+ symptoms. The median (interquartile range) values for the MDFS totals were 92.4 (76.4-98.6) for those with 0 symptoms; 78.5 (65.6-88.9) for those with 1 to 2 symptoms; and 54.2 (46.2-65.3) for those with 3+ symptoms. Similar group differences were observed for each PedsQL HRQoL and MDFS subscale score. CONCLUSIONS: Children and adolescents whose parents reported 1 to 2 PPCSs had lower HRQoL and more fatigue than those with 0 symptoms. Across all 3 groups, those with 3+ persistent symptoms had the lowest HRQoL and most fatigue. These findings indicate the continued need for intervention in this age group to prevent and address PPCSs.

Individual Symptom Report Prevalence in Children and Adolescents With One, Two, and Three or More Persistent Symptoms After Concussion: A Brief Report.

OBJECTIVE: To examine differences in individual symptom report prevalence between children and adolescents experiencing 1 to 2 versus ≥3 persistent postconcussion symptoms. DESIGN: A prospective cohort study. SETTING: Three community practice concussion clinics within a family practice network. PATIENTS: Children and adolescents aged 8 to 18 years presenting to clinics within 72 hours of a sport-related or recreation-related concussion. Those with complete symptom data from a 1-month follow-up time point (n = 236) were included in analyses. INDEPENDENT VARIABLES: One hundred thirty-six patients (n = 136) reported 0 symptoms as worse than preinjury at the 1-month time point. Participants reporting 1+ symptoms as worse than preinjury at 1 month were assigned to groups based on the number of symptoms endorsed: those with 1 to 2 (n = 38) compared with those experiencing ≥3 (n = 62). MAIN OUTCOME MEASURES: Fisher exact tests were used to compare symptom report prevalence for each item of the Rivermead Postconcussion Symptoms Questionnaire. This research question was formulated and examined after completion of data collection. RESULTS: Across both groups, headache and fatigue were the most commonly reported persistent postconcussion symptoms. Several emotional symptoms (eg, irritability, depression) were primarily or only present in those reporting ≥3 persistent symptoms. CONCLUSIONS: Findings provide detail regarding the clinical manifestation of experiencing fewer versus more persistent postconcussion symptoms, underscoring the importance of developing individualized, multifaceted rehabilitation programs.

Presence of Persistent Parent Reported Emotional and Behavioral-Related Concussion Symptoms Is Associated with Lower Health-Related Quality of Life in Adolescent Athletes.

Persistent concussion symptoms in adolescents are associated with lower health-related quality of life (HRQOL). The association between persistent emotional and behavioral-related concussion symptoms (EBS) and HRQOL is unknown, however. This study was a prospective cohort of adolescent athletes presenting to a concussion clinic within three days post-concussion and completing a one-month follow-up. The independent variable in these analyses was parent reported EBS symptom presence grouped as: (1) no EBS; (2) EBS present at pre-concussion levels; and (3) EBS worse than pre-concussion. The EBS included the following concussion symptoms: feeling irritable, depressed, frustrated/impatient, restless, reduced tolerance to stress/emotion, poor concentration, and fear of permanent symptoms. Dependent variables were parent reported psychosocial, physical, and total HRQOL. Separate multi-variable linear regression models controlling for age, sex, and concussion history were used to assess the association between EBS and HRQOL. Estimated adjusted mean differences (MD) and 95% confidence intervals (CI) were used to assess associations; MDs with a 95%CI excluding 0.0 were considered statistically significant. Overall, n = 245 presented to the study clinic three days post-concussion and completed the one-month follow-up (Mage = 14.28 ± 2.09 years, 59.02% male, 90.64% Caucasian, 31.84% with concussion history). At one-month post-concussion, adolescents with pre-concussion EBS levels had significantly lower psychosocial, physical, and total HRQOL than those with no EBS. In addition, those with EBS worse than pre-concussion had significantly lower psychosocial, physical, and total HRQOL than those with no EBS and EBS at pre-concussion levels. These findings highlight the importance of HRQOL assessments and that targeted interventions may be needed for those with EBS at one-month post-concussion to improve HRQOL.

An MRI protocol for anatomical and functional evaluation of the California sea lion brain.

BACKGROUND: Domoic acid (DOM) is a neurotoxin produced by some harmful algae blooms in coastal waters. California sea lions (Zalophus californianus) exposed to DOM often strand on beaches where they exhibit a variety of symptoms, including seizures. These animals typically show hippocampal atrophy on MRI scans. NEW METHOD: We describe an MRI protocol for comprehensive evaluation of DOM toxicosis in the sea lion brain. We intend to study brain development in pups exposed in utero. The protocol depicts the hippocampal formation as the primary region of interest. We include scans for quantitative morphometry, functional and structural connectivity, and a cerebral blood flow map. RESULTS: High-resolution 3D anatomical scans facilitate post hoc slicing in arbitrary planes and accurate morphometry. We demonstrate the first cerebral blood flow map using MRI, and the first structural tractography from a live sea lion brain. COMPARISON WITH EXISTING METHODS: Scans were compared to prior anatomical and functional studies in live sea lions, and structural connectivity in post mortem specimens. Hippocampal volumes were broadly in line with prior studies, with differences likely attributable to the 3D approach used here. Functional connectivity of the dorsal left hippocampus matched that found in a prior study conducted at a lower magnetic field, while structural connectivity in the live brain agreed with findings observed in post mortem studies. CONCLUSIONS: Our protocol provides a comprehensive, longitudinal view of the functional and anatomical changes expected to result from DOM toxicosis. It can also screen for other common neurological pathologies and is suitable for any pinniped that can fit inside an MRI scanner.

Algal toxin impairs sea lion memory and hippocampal connectivity, with implications for strandings.

Domoic acid (DA) is a naturally occurring neurotoxin known to harm marine animals. DA-producing algal blooms are increasing in size and frequency. Although chronic exposure is known to produce brain lesions, the influence of DA toxicosis on behavior in wild animals is unknown. We showed, in a large sample of wild sea lions, that spatial memory deficits are predicted by the extent of right dorsal hippocampal lesions related to natural exposure to DA and that exposure also disrupts hippocampal-thalamic brain networks. Because sea lions are dynamic foragers that rely on flexible navigation, impaired spatial memory may affect survival in the wild.