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The recently discovered Pa 30 nebula, the putative type Iax supernova remnant associated with the historical supernova of 1181 AD, shows puzzling characteristics that make it unique among known supernova remnants. In particular, Pa 30 exhibits a complex morphology, with a unique radial and filamentary structure, and it hosts a hot stellar remnant at its center, which displays oxygen-dominated, ultrafast winds. Because of the surviving stellar remnant and the lack of hydrogen and helium in its filaments, it has been suggested that Pa 30 is the product of a failed thermonuclear explosion in a near- or super-Chandrasekhar white dwarf, which created a subluminous transient, a rare subtype of the Ia class of supernovae called type Iax. We present here a detailed study of the 3D structure and velocities of a full radial section of the remnant. The Integral Field Unit observations, obtained with the new red channel of the Keck Cosmic Web Imager spectrograph, reveal that the ejecta are consistent with being ballistic, with velocities close to the free-expansion velocity. Additionally, we detect a large cavity inside the supernova remnant and a sharp inner edge to the filamentary structure, which coincides with the outer edge of a bright ring detected in infrared images. Finally, we detect a strong asymmetry in the amount of ejecta along the line of sight, which might hint at an asymmetric explosion. Our analysis provides strong confirmation that the explosion originated from SN 1181.

Abstract Veno‐occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a rare, serious complication following haematopoietic cell transplantation (HCT). This systematic literature review evaluated differences in clinical manifestations of VOD/SOS post‐HCT in adults and children. Medline and Embase were searched up to 4 March 2021 for reports of VOD/SOS post‐HCT; VOD/SOS diagnostic guidelines were included. Publications were evaluated based on inclusion of five cardinal clinical features of VOD/SOS (ascites, hepatomegaly, hyperbilirubinaemia, right upper quadrant [RUQ] pain and weight gain ≥5%). Overall, 204 publications were included. At diagnosis, hyperbilirubinaemia was more common in adults (93%) versus children (82%), weight gain ≥5% and hepatomegaly were more common in children (86%, 89%) versus adults (73%, 76%) and ascites and RUQ pain were similar between age groups. While 40% of cases had all five cardinal features, age was not a substantial determinant of the likelihood of missing any single specific feature. The proportion of cases, where hyperbilirubinaemia was the first recorded feature, was higher in children versus adults; weight gain and RUQ pain appeared first in a greater proportion of adults versus children. VOD/SOS diagnosis can be challenging; features may not present in a distinct sequence. This necessitates continuous vigilance by those involved in patient monitoring post‐HCT.

The objective of this paper is to model lost Quality Adjusted Life Years (QALYs) from symptoms arising from COVID-19 disease in the UK population, including symptoms of 'long-COVID'. The scope includes QALYs lost to symptoms, but not deaths, due to acute COVID-19 and long-COVID. The prevalence of symptomatic COVID-19, encompassing acute symptoms and long-COVID symptoms, was modelled using a decay function. Permanent injury as a result of COVID-19 infection, was modelled as a fixed prevalence. Both parts were combined to calculate QALY loss due to COVID-19 symptoms. Assuming a 60% final attack rate for SARS-CoV-2 infection in the population, we modelled 299,730 QALYs lost within 1 year of infection (90% due to symptomatic COVID-19 and 10% permanent injury) and 557,764 QALYs lost within 10 years of infection (49% due to symptomatic COVID-19 and 51% due to permanent injury). The UK Government willingness-to-pay to avoid these QALY losses would be £17.9 billion and £32.2 billion, respectively. Additionally, 90,143 people were subject to permanent injury from COVID-19 (0.14% of the population). Given the ongoing development in information in this area, we present a model framework for calculating the health economic impacts of symptoms following SARS-CoV-2 infection. This model framework can aid in quantifying the adverse health impact of COVID-19, long-COVID and permanent injury following COVID-19 in society and assist the proactive management of risk posed to health. Further research is needed using standardised measures of patient reported outcomes relevant to long-COVID and applied at a population level.

Brain health relies on a tightly regulated system known as neurovascular coupling whereby the cellular constituents of the neuro-glial-vascular unit (NGVU) regulate cerebral haemodynamics in accordance with brain metabolic demand. Disruption of neurovascular coupling impairs brain health and is associated with the development of a number for neurological conditions, including Alzheimer’s disease. The NGVU is also a key site of action for neuroinflammatory responses and contributes to the transition of systemic inflammation to neuroinflammatory processes. Thus, systemic inflammatory challenges may cause a shift in NGVU operation towards prioritising neuroinflammatory action and thus altering neurovascular coupling and resultant cerebrovascular changes. To investigate this, rats were injected with lipopolysaccharide (LPS) (2 ​mg/kg) to induce a systemic inflammatory response, or vehicle, and brain haemodynamic responses to sensory and non-sensory (hypercapnia) stimuli were assessed in vivo using optical imaging techniques. Following imaging, animals were perfused and their brains extracted to histologically characterise components of the NGVU to determine the association between underlying cellular changes and in vivo blood flow regulation. LPS-treated animals showed changes in haemodynamic function and cerebrovascular dynamics 6 ​hours after LPS administration. Histological assessment identified a significant increase in astrogliosis, microgliosis and endothelial activation in LPS-treated animals. Our data shows that an acutely induced systemic inflammatory response is able to rapidly alter in vivo haemodynamic function and is associated with significant changes in the cellular constituents of the NGVU. We suggest that these effects are initially mediated by endothelial cells, which are directly exposed to the circulating inflammatory stimulus and have been implicated in regulating functional hyperaemia.

Demanding biological imaging applications require extremely fast detection methods. Here, the authors demonstrate Line Excitation Array Detection, their developed technique for performing fluorescence microscopy in 3D with 0.8 million frames per second, by applying it to flow cytometry and neuron detection.

The United States Pacific whiting fishery uses mid-water trawl gear to target Pacific whiting off the United States West Coast. The fishery is subject to sector-specific bycatch caps for Chinook salmon (Oncorhynchus tshawytscha) and several rockfish species (widow rockfish–Sebastes entomelas, canary rockfish-Sebastes pinniger, darkblotched rockfish–Sebastes crameri, Pacific Ocean Perch (POP)-Sebastes alutus, and yelloweye rockfish-Sebastes ruberrimus). Chinook bycatch can include fish from endangered populations and rockfish stocks were recovering from severe depletion though most are now rebuilt. Catch of these species is rare and uncertain, making it difficult for vessels to meet strict individual performance standards. Consequently the industry has developed risk pools in which bycatch quota for a group of vessels is pooled, but vessels are required to follow practices that minimize bycatch risk including temporal and spatial fishing restrictions. The risk pools also require vessels to share information about bycatch hotspots enabling a cooperative approach to avoid bycatch based on real-time information. In this article we discuss the formation and structure of these risk pools, the bycatch reduction strategies they apply, and outcomes in the fishery in terms of observed bycatch avoidance behavior and utilization of target species. The analysis demonstrates the ability of these fishers to keep bycatch within aggregate limits and keep individual vessels from being tied up due to quota overages.

Large-scale screens on whole animals could facilitate drug discovery, but are technically challenging. Here, Mondal et al. develop a microfluidic chip combined with an automated imaging platform that enables high-throughput, high-resolution screening of Caenorhabditis elegansdisease models.

Anesthetized rodent models are ubiquitous in pre-clinical neuroimaging studies. However, because the associated cerebral morphology and experimental methodology results in a profound negative brain-core temperature differential, cerebral temperature changes during functional activation are likely to be principally driven by local inflow of fresh, core-temperature, blood. This presents a confound to the interpretation of blood-oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) data acquired from such models, since this signal is also critically temperature-dependent. Nevertheless, previous investigation on the subject is surprisingly sparse. Here, we address this issue through use of a novel multi-modal methodology in the urethane anesthetized rat. We reveal that sensory stimulation, hypercapnia and recurrent acute seizures induce significant increases in cortical temperature that are preferentially correlated to changes in total hemoglobin concentration (Hbt), relative to cerebral blood flow and oxidative metabolism. Furthermore, using a phantom-based evaluation of the effect of such temperature changes on the BOLD fMRI signal, we demonstrate a robust inverse relationship between both variables. These findings suggest that temperature increases, due to functional hyperemia, should be accounted for to ensure accurate interpretation of BOLD fMRI signals in pre-clinical neuroimaging studies.

There is a continuing need for driver strains to enable cell-type-specific manipulation in the nervous system. Each cell type expresses a unique set of genes, and recapitulating expression of marker genes by BAC transgenesis or knock-in has generated useful transgenic mouse lines. However, since genes are often expressed in many cell types, many of these lines have relatively broad expression patterns. We report an alternative transgenic approach capturing distal enhancers for more focused expression. We identified an enhancer trap probe often producing restricted reporter expression and developed efficient enhancer trap screening with the PiggyBac transposon. We established more than 200 lines and found many lines that label small subsets of neurons in brain substructures, including known and novel cell types. Images and other information about each line are available online (enhancertrap.bio.brandeis.edu).

We present evidence that there can be substantial variation in species richness in residential areas differing in their socioeconomic and cultural characteristics. Many analyses of the impacts of urbanization on biodiversity rely on traditional "urban-to-rural" gradient measures, such as distance from urban center or population density, and thus can fail to account for the ways in which human socioeconomic and cultural characteristics are shaping the human-environment interaction and ecological outcomes. This influence of residential values and economic resources on biodiversity within the urban matrix has implications for human quality of life, for urban conservation strategies, and for urban planning.