Background: Despite the utility of administrative health data, there remains a lack of patient-centered outcome measures to meaningfully capture morbidity after traumatic brain injury (TBI). We sought to characterize and validate days at home (DAH) as a feasible measure to assess population-level moderate to severe TBI (msTBI) outcomes and health resource utilization. Methods: We utilized linked health administrative data sources to identify adults with msTBI patients presenting to trauma centers in Ontario injured between 2009-2021. DAH at 180 days reflects the total number of days spent alive and at home excluding the days spent institutionalized in acute care, rehabilitation, inpatient mental health settings or post-acute readmissions. Construct and predictive validity were determined; we additionally estimated minimally important difference (MID) in DAH180days. Results: There were 6340 patients that met inclusion criteria. Median DAH180days were 70 days (interquartile range 0-144). Increased health resource utilization at baseline, older age, increasing cranial injury severity and major extracranial injuries were significantly associated with fewer DAH180days. DAH180days was correlated to DAH counts at 1-3 years. The average MID estimate from anchor-based and distribution-based methods was 18 days. Conclusions: We introduce DAH180days as a feasible and sufficiently responsive patient-centered outcome measure with construct, predictive and face validity in an msTBI population.

Background: Employment and personal income loss after traumatic brain injury (TBI) is a major source of post-injury stress and barrier to societal reintegration for affected patients. We sought to quantify the labor market implications for tax-filing adult TBI survivors. Methods: We performed a matched difference-in-difference analysis using a national retrospective cohort of working adult TBI survivors injured between 2007-2017. Linear and logistic mixed effects regressions were used to estimate the magnitude of personal income loss and proportion of patients displaced from the workforce in the three post-injury years (Y+1 to Y+3). Results: Among 18,050 patients identified with TBI, the adjusted average loss of personal annual income was $-7,635 dollars in Y+1 and $-5,000 in Y+3. An additional -7.8% individuals were newly unemployed compared to the pre-injury baseline. For mild, moderate, and severe TBI subgroups, income loss was $-3354, $-6750, and $-17375 respectively in Y+3; the proportion of newly unemployed individuals in Y+3 was 5.8%, 9.2%, and 20% lower than baseline. We estimated 500 million dollars of incurred labor markets losses related to TBI in Canada. Conclusions: This work represents the first national cohort data quantifying the labor market implications of TBI. These results may be used to inform post-injury care pathways and vocational rehabilitation.

Background: The late-onset cerebellar ataxias (LOCAs) have until recently resisted molecular diagnosis. Contributing to this diagnostic gap is that non-coding structural variations, such as repeat expansions, are not fully accessible to standard short-read sequencing analysis. Methods: We combined bioinformatics analysis of whole-genome sequencing and long-read sequencing to search for repeat expansions in patients with LOCA. We enrolled 66 French-Canadian, 228 German, 20 Australian and 31 Indian patients. Pathogenic mechanisms were studied in post-mortem cerebellum and induced pluripotent stem cell (iPSC)-derived motor neurons from 2 patients. Results: We identified 128 patients who carried an autosomal dominant GAA repeat expansion in the first intron of the FGF14 gene. The expansion was present in 61%, 18%, 15% and 10% of patients in the French-Canadian, German, Australian and Indian cohorts, respectively. The pathogenic threshold was determined to be (GAA)≥250, although incomplete penetrance was observed in the (GAA)250-300 range. Patients developed a slowly progressive cerebellar syndrome at an average age of 59 years. Patient-derived post-mortem cerebellum and induced motor neurons both showed reduction in FGF14 RNA and protein expression compared to controls. Conclusions: This intronic, dominantly inherited GAA repeat expansion in FGF14 represents one of the most common genetic causes of LOCA uncovered to date.

Frontal ablation, the combination of submarine melting and iceberg calving, changes the geometry of a glacier's terminus, influencing glacier dynamics, the fate of upwelling plumes and the distribution of submarine meltwater input into the ocean. Directly observing frontal ablation and terminus morphology below the waterline is difficult, however, limiting our understanding of these coupled ice–ocean processes. To investigate the evolution of a tidewater glacier's submarine terminus, we combine 3-D multibeam point clouds of the subsurface ice face at LeConte Glacier, Alaska, with concurrent observations of environmental conditions during three field campaigns between 2016 and 2018. We observe terminus morphology that was predominately overcut (52% in August 2016, 63% in May 2017 and 74% in September 2018), accompanied by high multibeam sonar-derived melt rates (4.84 m d−1 in 2016, 1.13 m d−1 in 2017 and 1.85 m d−1 in 2018). We find that periods of high subglacial discharge lead to localized undercut discharge outlets, but adjacent to these outlets the terminus maintains significantly overcut geometry, with an ice ramp that protrudes 75 m into the fjord in 2017 and 125 m in 2018. Our data challenge the assumption that tidewater glacier termini are largely undercut during periods of high submarine melting.

Spectral-broadening of the APOLLON PW-class laser pulses using a thin-film compression technique within the long-focal-area interaction chamber of the APOLLON laser facility is reported, demonstrating the delivery of the full energy pulse to the target interaction area. The laser pulse at 7 J passing through large aperture, thin glass wafers is spectrally broadened to a bandwidth that is compatible with a 15-fs pulse, indicating also the possibility to achieve sub-10-fs pulses using 14 J. Placing the post-compressor near the interaction makes for an economical method to produce the shortest pulses by limiting the need for high damage, broadband optics close to the final target rather than throughout the entire laser transport system.

Background: Ischemic stroke occurs following trauma-related blunt cerebrovascular injury (BCVI) in up to 20% of cases. Preventative treatment includes antiplatelets, anticoagulants, and/or endovascular treatment (ET), but the optimal choice remains unclear. The objective of this study was to compare the ischemic stroke rate between these three treatments. Methods: Following PRISMA guidelines, we queried the OVID Medline, Embase, Web of Science, and Cochrane Library databases from September 2019 to inception to identify studies reporting treatment-stratified outcomes in BCVI patients. Meta-analysis was performed to compare outcomes between the treatment groups, using odds ratios. Retrospective review of our institutional experience with BCVI outcomes was performed and added to the meta-analysis. Results: Analysis of seven comparative studies of antiplatelets (n=334) versus anticoagulation (n=325) found no significant difference in ischemic stroke rate (OR 1.27, 95%CI 0.40-3.99), but a decrease in hemorrhagic complications (OR 0.38, 95%CI 0.15-1.00). Analysis of seven comparative studies of antiplatelets/anticoagulants (n=805) versus ET (n=235) also found no significant difference in stroke rate (OR 0.71, 95%CI 0.35-1.42). Conclusions: Antiplatelets and anticoagulants were similarly effective in reducing ischemic stroke risk in BCVI, but antiplatelets were better tolerated in this trauma population. The addition of endovascular treatment did not further reduce stroke risk compared to antiplatelets or anticoagulants alone.

The Drygalski Ice Tongue in East Antarctica stretches 90 km into the Ross Sea and influences the local ocean circulation, and persistence of the Terra Nova Bay Polynya. We examine the controls on the size of this floating ice body by comparing the propagation of six large fractures on the ice tongue's northern side using 21 years of Landsat imagery with hydrostatic ice thickness maps and strain rate calculations. We also apply a subglacial hydrology model to estimate the location and discharge from subglacial channels over the grounding line and compare these with basal channels identified along the ice tongue using remote sensing and airborne radar data. Our results suggest that large fractures are inhibited from full-width propagation by thicker ice between basal channels. We hypothesize that only once the ice tongue thins towards the terminus, can fractures propagate and cause large calving events. This suggests an important relationship between the melting of floating ice from subglacial and ocean sources and the expansion of fractures that lead to ice tongue calving.

Brain alterations have been sought since the beginning of the century to explain the ‘dementia’ of dementia præcox. Kraepelin suggested in 1913 that it might have its internal origins in early childhood, while Southard (1915) considered likely a congenital or early acquired basis for the development of the disease. Afterwards, degenerative processes were described for decades until neurodevelopmental theories emerged recently (Lewis, 1988).

Using pneumoencephalography, Jacobi and Winkler (1927) first reported that some patients with schizophrenia presented enlarged ventricles. Johnstone et al (1976, 1978), in CT-scan studies, observed an increase in mean lateral ventricular size in a group of institutionalized schizophrenic patients. This finding has been replicated by other studies (Weinberger et al, 1983) but challenged by others (Gluck et al, 1980; Jernigan et al, 1982).

Ten ice-sheet models are used to study sensitivity of the Greenland and Antarctic ice sheets to prescribed changes of surface mass balance, sub-ice-shelf melting and basal sliding. Results exhibit a large range in projected contributions to sea-level change. In most cases, the ice volume above flotation lost is linearly dependent on the strength of the forcing. Combinations of forcings can be closely approximated by linearly summing the contributions from single forcing experiments, suggesting that nonlinear feedbacks are modest. Our models indicate that Greenland is more sensitive than Antarctica to likely atmospheric changes in temperature and precipitation, while Antarctica is more sensitive to increased ice-shelf basal melting. An experiment approximating the Intergovernmental Panel on Climate Change’s RCP8.5 scenario produces additional first-century contributions to sea level of 22.3 and 8.1 cm from Greenland and Antarctica, respectively, with a range among models of 62 and 14 cm, respectively. By 200 years, projections increase to 53.2 and 26.7 cm, respectively, with ranges of 79 and 43 cm. Linear interpolation of the sensitivity results closely approximates these projections, revealing the relative contributions of the individual forcings on the combined volume change and suggesting that total ice-sheet response to complicated forcings over 200 years can be linearized.

The objective of the Apollon 10 PW project is the generation of 10 PW peak power pulses of 15 fs at $1~\text{shot}~\text{min}^{-1}$. In this paper a brief update on the current status of the Apollon project is presented, followed by a more detailed presentation of our experimental and theoretical investigations of the temporal characteristics of the laser. More specifically the design considerations as well as the technological and physical limitations to achieve the intended pulse duration and contrast are discussed.

The objective of the Apollon project is the generation of 10 PW peak power pulses of 15 fs at 1 shot/minute. In this paper the Apollon facility design, the technological challenges and the current progress of the project will be presented.

Selective laser sintering (SLS) is a rapidly developing additive manufacturing technique, with advantages in flexibility and low material waste. Many parameters used in a SLS process are determined by powder type: blended powders have limitations due to wetting and diffusion, while prealloyed powders require processing in a small temperature range dictated by the alloy composition. As an alternative to these, a coated powder was fabricated by electrochemical means. This tin–copper composite powder was compared with a blend of tin and copper powders, using metallographic, crystallographic, and thermal analysis techniques as well as SLS. It was found that, because of the uniform distribution of liquid and increased contact between phases in the composite powder, sintering took place in the composite powder but not in the blend. After a homogenization treatment, mechanical testing of the sintered samples showed that the strength and ductility were comparable to high-porosity materials produced using other techniques.