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Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350
m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200
m images will also have a factor
30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
Declining mortality following invasive pneumococcal disease (IPD) has been observed concurrent with a reduced incidence due to effective pneumococcal conjugate vaccines. However, with IPD now increasing due to serotype replacement, we undertook a statistical analysis to estimate the trend in all-cause 30-day case fatality rate (CFR) in the North East of England (NEE) following IPD. Clinical, microbiological and demographic data were obtained for all laboratory-confirmed IPD cases (April 2006–March 2016) and the adjusted association between CFR and epidemiological year estimated using logistic regression. Of the 2510 episodes of IPD included in the analysis, 486 died within 30 days of IPD (CFR 19%). Increasing age, male sex, a diagnosis of septicaemia, being in ⩾1 clinical risk groups, alcohol abuse and individual serotypes were independently associated with increased CFR. A significant decline in CFR over time was observed following adjustment for these significant predictors (adjusted odds ratio 0.93, 95% confidence interval 0.89–0.98; P = 0.003). A small but significant decline in 30-day all-cause CFR following IPD has been observed in the NEE. Nonetheless, certain population groups remain at increased risk of dying following IPD. Despite the introduction of effective vaccines, further strategies to reduce the ongoing burden of mortality from IPD are needed.
Analyzing audiovisual communication is challenging because its content is highly symbolic and less rule-governed than verbal material. But audiovisual messages are important to understand: they amplify, enrich, and complicate the meaning of textual information. We describe a fully-reproducible approach to analyzing video content using minimally—but systematically—trained online workers. By aggregating the work of multiple coders, we achieve reliability, validity, and costs that equal those of traditional, intensively trained research assistants, with much greater speed, transparency, and replicability. We argue that measurement strategies relying on the “wisdom of the crowd” provide unique advantages for researchers analyzing complex and intricate audiovisual political content.
Eight latest Eocene to earliest Miocene stratigraphic surfaces have been identified in petroleum well data from the Taranaki Basin, New Zealand. These surfaces define seven regional sedimentary packages, of variable thickness and lithofacies, forming a mixed siliciclastic–carbonate system. The evolving tectonic setting, particularly the initial development of the Australian–Pacific convergent margin, controlled geographic, stratigraphic and facies variability. This tectonic signal overprinted a regional transgressive trend that culminated in latest Oligocene times. The earliest influence of active compressional tectonics is reflected in the preservation of latest Eocene – Early Oligocene deepwater sediments in the northern Taranaki Basin. Thickness patterns for all mid Oligocene units onwards show a shift in sedimentation to the eastern Taranaki Basin, controlled by reverse movement on the Taranaki Fault System. This resulted in the deposition of a thick sedimentary wedge, initially of coarse clastic sediments, later carbonate dominated, in the foredeep close to the fault. In contrast, Oligocene active normal faulting in a small sub-basin in the south may represent the most northerly evidence for rifting in southern Zealandia, related to Emerald Basin formation. The Early Miocene period saw a return to clastic-dominated deposition, the onset of regional regression and the southward propagation of compressional tectonics.
In the study of X-ray absorption fine structure, one is faced with the task of measuring sample absorbance over an extended wavelength region. For the sake of accuracy, these measurements are often carried out on a fixed-count basis. Manual collection of the data at a hundred or more spectrometer settings is a tedious and time-consuming chore. This paper describes an automated system for accumulating absorption data.
The equipment is used in conjunction with a Philips wide-range goniometer employed as a single-crystal spectrometer. It consists of: (1) a four-position sample changer, (2) a fixed-count selector for each sample position, (3) a five-digit counter and paper tape printer which register and record sample identification and counting times based on a 60-cps clock frequency, and (4) a programmer. The spectrometer advance is accomplished using the Philips step-scan arrangement. An IBM 7094 FORTRAN program for data reduction and computation will be described. The possibility of using X-ray absorption fine-structure measurements as a quantitative method for determining the various absorbing species will be discussed.
Detecting gastrointestinal (GI) infection transmission among men who have sex with men (MSM) in England is complicated by a lack of routine sexual behavioural data. We investigated whether gender distributions might generate signals for increased transmission of GI pathogens among MSM. We examined the percentage male of laboratory-confirmed patient-episodes for patients with no known travel history for 10 GI infections of public health interest in England between 2003 and 2013, stratified by age and region. An adult male excess was observed for Shigella spp. (annual maximum 71% male); most pronounced for those aged 25–49 years and living in London, Brighton and Manchester. An adult male excess was observed every year for Entamoeba histolytica (range 59.8–76.1% male), Giardia (53.1–57.6%) and Campylobacter (52.1–53.5%) and for a minority of years for hepatitis A (max. 69.8%) and typhoidal salmonella (max. 65.7%). This approach generated a signal for excess male episodes for six GI pathogens, including a characterised outbreak of Shigella among MSM. Stratified analyses by geography and age group were consistent with MSM transmission for Shigella. Optimisation and routine application of this technique by public health authorities elsewhere might help identify potential GI infection outbreaks due to sexual transmission among MSM, for further investigation.
A critical question in invasion biology involves the relative importance of propagule rain and community invasibility. For plant invasions, invasibility is often related to disturbance, but few studies of forest invaders have simultaneously investigated both canopy and ground-level disturbance. We investigated the relative importance of seed rain, canopy disturbance, and soil disturbance in a mature forest in Maryland on the recruitment of four invasive species: wine raspberry (Rubus phoenicolasius Maxim.), Japanese barberry (Berberis thunbergii DC), multiflora rose (Rosa multiflora Thunb.), and Japanese stiltgrass [Microstegium vimineum (Trin.) A. Camus]. Using complete censuses of a 9-ha plot at two points in time (2011–12 and 2014), we mapped new recruits, and related their locations to canopy and soil disturbance, as well as to a seed rain index based on locations of reproducing plants and seed-dispersal kernels.
We found that propagule rain, as measured by the seed rain index, was a significant predictor of recruitment for B. thunbergii, R. phoenicolasius, and M. vimineum. For R. multiflora, seed sources were not located, precluding assessment of propagule rain, but recruitment was linked to canopy disturbance, as was recruitment of M. vimineum. However, because reproduction of R. phoenicolasius and, in some years, of B. thunbergii is higher in treefall gaps, these gaps experience higher propagule rain, with the result that recruitment is indirectly associated with these gaps. Ground-layer disturbance was an important predictor of recruitment only for B. thunbergii. Our findings reveal that the importance of propagule rain is the most consistent driver of recruitment, but canopy or ground-layer disturbance promotes recruitment of some invasive plant species.
Protected areas are central to global efforts to prevent species extinctions, with many countries investing heavily in their establishment. Yet the designation of protected areas alone can only abate certain threats to biodiversity. Targeted management within protected areas is often required to achieve fully effective conservation within their boundaries. It remains unclear what combination of protected area designation and management is needed to remove the suite of processes that imperil species. Here, using Australia as a case study, we use a dataset on the pressures facing threatened species to determine the role of protected areas and management in conserving imperilled species. We found that protected areas that are not resourced for threat management could remove one or more threats to 1,185 (76%) species and all threats to very few (n = 51, 3%) species. In contrast, a protected area network that is adequately resourced to manage threatening processes within their boundary could remove one or more threats to almost all species (n = 1,551; c. 100%) and all threats to almost half (n = 740, 48%). However, 815 (52%) species face one or more threats that require coordinated conservation actions that protected areas alone could not remove. This research shows that investing in the continued expansion of Australia's protected area network without providing adequate funding for threat management within and beyond the existing protected area network will benefit few threatened species. These findings highlight that as the international community expands the global protected area network in accordance with the 2020 Strategic Plan for Biodiversity, a greater emphasis on the effectiveness of threat management is needed.
Introduction: Emergency Department Overcrowding (EDOC) is a multifactorial issue that leads to Access Block for patients needing emergency care. Identified as a national problem, patients presenting to a Canadian Emergency Department (ED) at a time of overcrowding have higher rates of admission to hospital and increased seven-day mortality. Using the well accepted input-throughput-output model to study EDOC, current research has focused on throughput as a measure of patient flow, reported as ED length of stay (LOS). In fact, ED LOS and ED beds occupied by inpatients are two “extremely important indicators of EDOC identified by a 2005 survey of Canadian ED directors. One proposed solution to improve ED throughput is to utilize a physician at triage (PAT) to rapidly assess newly arriving patients. In 2017, a pilot PAT program was trialed at Kelowna General Hospital (KGH), a tertiary care hospital, as part of a PDSA cycle. The aim was to mitigate EDOC by improving ED throughput by the end of 2018, to meet the national targets for ED LOS suggested in the 2013 CAEP position statement. Methods: During the fiscal periods 1-6 (April 1 to September 7, 2017) a PAT shift occurred daily from 1000-2200, over four long weekends. ED LOS, time to inpatient bed, time to physician initial assessment (PIA), number of British Columbia Ambulance Service (BCAS) offload delays, and number of patients who left without being seen (LWBS) were extracted from an administrative database. Results were retrospectively analyzed and compared to data from 1000-2200 of non-PAT trial days during the trial periods. Results: Median ED LOS decreased from 3.8 to 3.4 hours for high-acuity patients (CTAS 1-3), from 2.1 to 1.8 hours for low-acuity patients (CTAS 4-5), and from 9.3 to 8.0 hours for all admitted patients. During PAT trial weekends, there was a decrease in the average time to PIA by 65% (from 73 to 26 minutes for CTAS 2-5), average number of daily BCAS offload delays by 39% (from 2.3 to 1.4 delays per day), and number of patients who LWBS from 2.4% to 1.7%. Conclusion: The implementation of PAT was associated with improvements in all five measures of ED throughput, providing a potential solution for EDOC at KGH. ED LOS was reduced compared to non-PAT control days, successfully meeting the suggested national targets. PAT could improve efficiency, resulting in the ability to see more patients in the ED, and increase the quality and safety of ED practice. Next, we hope to prospectively evaluate PAT, continuing to analyze these process measures, perform a cost-benefit analysis, and formally assess ED staff and patient perceptions of the program.
Schmidt hammer (SH) sampling of 54 10Be-dated granite surfaces from the Pyrenees reveals a clear relationship between exposure and weathering through time (n=52, R2=0.96, P<0.01) and permits the use of the SH as a numerical dating tool. To test this 10Be-SH calibration curve, 100 surfaces were sampled from five ice-front positions in the Têt catchment, eastern Pyrenees, with results verified against independent 10Be and 14C ages. Gaussian modelling differentiates Holocene (9.4±0.6 ka), Younger Dryas (12.6±0.9 ka), Oldest Dryas (16.1±0.5 ka), last glacial maximum (LGM; 24.8±0.9 ka) and Würmian maximum ice extent stages (MIE; 40.9±1.1 ka). These data confirm comparable glacier lengths during the LGM and MIE (~300 m difference), in contrast to evidence from the western Pyrenees (≥15 km), reflecting the relative influence of Atlantic and Mediterranean climates. Moreover, Pyrenean glaciers advanced significantly during the LGM, with a local maximum at ~25 ka, driven by growth of the Laurentide Ice Sheet, southward advection of the polar front, and a solar radiation minimum in the Northern Hemisphere. This calibration curve is available online (http://shed.earth) to enable wider application of this method throughout the Pyrenees.
Sinus venosus atrial septal defect can result in an increase in pulmonary blood flow and vascular resistance, leading to pulmonary hypertension. Rarely, the degree of pulmonary hypertension is out of proportion to the degree of intra-cardiac shunting. This case outlines the differences between pulmonary hypertension secondary to CHD and idiopathic pulmonary hypertension, and illustrates the investigation and management strategy used in a patient with features of both.
This paper presents an overview of internal layering across Pine Island Glacier, West Antarctica, as measured from airborne-radar data acquired during a survey conducted by the British Antarctic Survey and the University of Texas in the 2004/05 season. Internal layering is classified according to type (continuous/discontinuous/missing) and the results compared with InSAR velocities. Several areas exhibit disruption of internal layers that is most likely caused by large basal shear stresses. Signs of changes in flow were identified in a few inter-tributary areas, but overall the layering classification and distribution of layers indicate that only minor changes in ice-flow regime have taken place. This is supported by bed-topography data that show the main trunk of the glacier, as well as some of the tributaries, are topographically controlled and located in deep basins.
Airborne radio-echo sounding investigations in the upper reaches of Bailey Ice Stream and Slessor Glacier, Coats Land, East Antarctica, have shown that enhanced-flow tributaries are associated with well-defined areas of relatively thicker ice, and are separated from each other by areas of relatively thinner ice. A numerical modelling study has revealed that while internal ice deformation might account for all the observed flow in inter-tributary areas and the majority in the Slessor tributaries, a significant proportion of the flow of Bailey tributary is attributable to basal motion. Further, investigations of depth-corrected basal reflection power indicate that the bed underlying both Bailey and Slessor enhanced-flow tributaries is significantly smoother than in the slower-moving inter-tributary areas. It is thus proposed that enhanced motion within Bailey tributary (and also perhaps Slessor) may be facilitated by a reduction in basal roughness, caused by the accumulation of water and/or sediments within subglacial valleys, or by the erosion and smoothing of bed obstacles.
Rutford Ice Stream and Carlson Inlet are neighbouring glaciers in West Antarctica. Rutford Ice Stream flows at speeds greater than 350 m a−1, whereas Carlson Inlet, which has some similar dimensions and supports a similar driving stress, flows 10–50 times slower. We discuss a range of observations concerning Carlson Inlet, and conclude that there is good indirect evidence that it is a relict ice stream, which ceased streaming more than 240 years BP, but sufficiently recently that its surface morphology, basal water content and basal morphology still retain characteristics produced by streaming. An analysis of expected subglacial drainage pathways indicates that Carlson Inlet is not streaming because it is currently starved of subglacial water, which is currently directed beneath Rutford Ice Stream. This current state of water piracy by Rutford Ice Stream is, however, sensitive to minor thickness changes on the ice streams; a ∼120 m (<4%) thickening of Rutford Ice Stream would divert almost all the subglacial water in the system towards Carlson Inlet and could reactivate its flow. The result highlights the importance of subglacial drainage in controlling ice-stream evolution and the requirement for ice-sheet models to couple ice flow with subglacial drainage.
An almost inertial celestial reference frame based upon extragalactic sources is in the process of being established. This reference frame is to be global with a minimum density of one source/100 square degrees. The source positions will be based upon radio observations and will allow optical reference frames to be related to this frame at the 0.03 arc second level.