Here, we describe the Compact Array Broad-band Backend (CABB) and present first results obtained with the upgraded Australia Telescope Compact Array (ATCA). The 16-fold increase in observing ...bandwidth, from 2 × 128 to 2 × 2048 MHz, high-bit sampling and the addition of 16 zoom windows (each divided into further 2048 channels) provide major improvements for all ATCA observations. The benefits of the new system are: (1) hugely increased radio continuum and polarization sensitivity as well as image fidelity; (2) substantially improved capability to search for and map emission and absorption lines over large velocity ranges; (3) simultaneous multi-line and continuum observations; (4) increased sensitivity, survey speed and dynamic range due to high-bit sampling and (5) high-velocity resolution, while maintaining full polarization output. The new CABB system encourages all observers to make use of both spectral line and continuum data to achieve their full potential.
Given the dramatic increase of the ATCA capabilities in all bands (ranging from 1.1 to 105 GHz) CABB enables scientific projects that were not feasible before the upgrade, such as simultaneous observations of multiple spectral lines, on-the-fly mapping, fast follow-up of radio transients (e.g. the radio afterglow of new supernovae) and maser observation at high-velocity resolution and full polarization. The first science results presented here include wide-band spectra, high dynamic-range images and polarization measurements, highlighting the increased capability and discovery potential of the ATCA.
ABSTRACT
Shoreline and shelf‐edge trajectories describe the migration through time of sedimentary systems, using geomorphological breaks‐in‐slope that are associated with key changes in depositional ...processes and products. Analysis of these trajectories provides a simple descriptive tool that complements and extends conventional sequence stratigraphic methods and models. Trajectory analysis offers four advantages over a sequence stratigraphic interpretation based on systems tracts: (1) each genetically related advance or retreat of a shoreline or shelf edge is viewed in the context of a continuously evolving depositional system, rather than as several discrete systems tracts; (2) subtle changes in depositional response (e.g. within systems tracts) can be identified and honoured; (3) trajectory analysis does not anticipate the succession of depositional events implied by systems‐tract models; and (4) the descriptive emphasis of trajectory analysis does not involve any a priori assumptions about the type or nature of the mechanisms that drive sequence development. These four points allow the level of detail in a trajectory‐based interpretation to be directly tailored to the available data, such that the interpretation may be qualitative or quantitative in two or three dimensions. Four classes of shoreline trajectory are recognized: ascending regressive, descending regressive, transgressive and stationary (i.e. nonmigratory). Ascending regressive and high‐angle (accretionary) transgressive trajectories are associated with expanded facies belt thicknesses, the absence of laterally extensive erosional surfaces, and relatively high preservation of the shoreline depositional system. In contrast, descending regressive and low‐angle (nonaccretionary) transgressive trajectories are associated with foreshortened and/or missing facies belts, the presence of laterally extensive erosional surfaces, and relatively low preservation of the shoreline depositional system. Stationary trajectories record shorelines positioned at a steeply sloping shelf edge, with accompanying bypass of sediment to the basin floor. Shelf‐edge trajectories represent larger spatial and temporal scales than shoreline trajectories, and they can be subdivided into ascending, descending and stationary (i.e. nonmigratory) classes. Ascending trajectories are associated with a relatively large number and thickness of shoreline tongues (parasequences), the absence of laterally extensive erosional surfaces on the shelf, and relatively low sediment supply to the basin floor. Descending trajectories are associated with a few, thin shoreline tongues, the presence of laterally extensive erosional surfaces on the shelf, and high sediment supply to basin‐floor fan systems. Stationary trajectories record near‐total bypass of sediment across the shelf and mass transfer to the basin floor.
With an increasingly ageing population, osteoporosis and osteoporosis-related fractures is fast becoming an important public health problem placing a considerable economic burden on health service ...resources. This does not account for the substantial pain, disability and indeed mortality incurred after a fracture, particularly a hip fracture. Osteoporosis is a systemic skeletal disorder which results from an imbalance in bone remodeling. This leads to a reduction in bone strength and increased susceptibility to fracture. It affects up to 1 in 2 women and 1 in 5 men. In the past 2 decades, there have been significant advances in bone biology which have helped in the understanding of the pathogenesis of osteoporosis and have led to improved therapies. In developing strategies for fracture prevention, it is important to identify those individuals with the highest fracture risk who will require pharmacological intervention. Treatment is aimed at fracture prevention and includes modification of general lifestyle factors which have been linked to fractures in epidemiological studies and ensuring optimum calcium and vitamin D intake as adjunct to active anti-fracture therapy. A number of drugs are now approved for the treatment of osteoporosis. This review article will describe the pathogenesis of osteoporosis and focus on the methods currently in use for the identification of patients at high fracture risk and will highlight their usefulness and limitations. The existing anti-fracture pharmacotherapies and those in development will be reviewed. Assessment of their effectiveness including the use of biochemical markers of bone turnover in this clinical context will be reviewed.
OBJECTIVETo analyze the association between peri-ictal brainstem posturing semiologies with post-ictal generalized electroencephalographic suppression (PGES) and breathing dysfunction in generalized ...convulsive seizures (GCS).
METHODSProspective, multicenter analysis of GCS. Ictal brainstem semiology was classified as (1) decerebrationbilateral symmetric tonic arm extension, (2) decorticationbilateral symmetric tonic arm flexion only, (3) hemi-decerebrationunilateral tonic arm extension with contralateral flexion and (4) absence of ictal tonic phase. Post-ictal posturing was also assessed. Respiration was monitored using thoraco-abdominal belts, video and pulse oximetry.
RESULTSTwo hundred ninety-five seizures (180 patients) were analyzed. Ictal decerebration was observed in 122/295 (41.4%), decortication in 47/295 (15.9%) and hemi-decerebration in 28/295 (9.5%) seizures. Tonic phase was absent in 98/295 (33.2%) seizures. Postictal posturing occurred in 18/295 (6.1%) seizures. PGES risk increased with ictal decerebration (OR 14.79, 95% CI 6.18–35.39, p < 0.001), decortication (OR 11.26, 95% CI 2.96–42.93, p < 0.001), or hemi-decerebration (OR 48.56, 95% CI 6.07–388.78, p < 0.001) Ictal decerebration was associated with longer PGES (p = 0.011). Post-ictal posturing was associated with post-convulsive central apnea (PCCA) (p = 0.004), longer hypoxemia (p < 0.001) and SpO2 recovery (p = 0.035).
CONCLUSIONSIctal brainstem semiology is associated with increased PGES risk. Ictal decerebration is associated with longer PGES. Post-ictal posturing is associated with a threefold increased risk of PCCA, longer hypoxemia and SpO2 recovery. Peri-ictal brainstem posturing may be surrogate biomarkers for GCS severity identifiable without in-hospital monitoring.
CLASSIFICATION OF EVIDENCEThis study provides Class III evidence that peri-ictal brainstem posturing is associated with the GCS with more prolonged PGES and more severe breathing dysfunction.
This article, the second in the series, presents kinetic and photochemical data evaluated by the IUPAC Subcommittee on Gas Kinetic Data Evaluation for Atmospheric Chemistry. It covers the gas phase ...and photochemical reactions of Organic species, which were last published in 1999, and were updated on the IUPAC website in late 2002, and subsequently during the preparation of this article. The article consists of a summary table of the recommended rate coefficients, containing the recommended kinetic parameters for the evaluated reactions, and eight appendices containing the data sheets, which provide information upon which the recommendations are made.
It is acknowledged that the COVID-19 pandemic has caused profound disruption to the delivery of healthcare services globally. This has affected the management of many long-term conditions including ...osteoporosis as resources are diverted to cover urgent care. Osteoporosis is a public health concern worldwide and treatment is required for the prevention of further bone loss, deterioration of skeletal micro-architecture, and fragility fractures. This review provides information on how the COVID-19 pandemic has impacted the diagnosis and management of osteoporosis. We also provide clinical recommendations on the adaptation of care pathways based on experience from five referral centres to ensure that patients with osteoporosis are still treated and to reduce the risk of fractures both for the individual patient and on a societal basis. We address the use of the FRAX tool for risk stratification and initiation of osteoporosis treatment and discuss the potential adaptations to treatment pathways in view of limitations on the availability of DXA. We focus on the issues surrounding initiation and maintenance of treatment for patients on parenteral therapies such as zoledronate, denosumab, teriparatide, and romosozumab during the pandemic. The design of these innovative care pathways for the management of patients with osteoporosis may also provide a platform for future improvement to osteoporosis services when routine clinical care resumes.
Adaptive optics is a relatively new field, yet it is spreading rapidly and allows new questions to be asked about how the visual system is organized. The editors of this feature issue have posed a ...series of question to scientists involved in using adaptive optics in vision science. The questions are focused on three main areas. In the first we investigate the use of adaptive optics for psychophysical measurements of visual system function and for improving the optics of the eye. In the second, we look at the applications and impact of adaptive optics on retinal imaging and its promise for basic and applied research. In the third, we explore how adaptive optics is being used to improve our understanding of the neurophysiology of the visual system.
To capture the perspective of prospective urology applicants experiencing unique challenges in the context of COVID-19.
A voluntary, anonymous survey was distributed online, assessing the impact of ...COVID-19 on a large sample of US medical students planning to apply to urology residencies. Themes of (1) specialty discernment, (2) alterations to medical education, and (3) the residency application process were explored.
A total of 238 medical students, 87% third and fourth years, responded to the survey. While 85% indicated that the pandemic had not deterred their specialty choice, they noted substantial impacts on education, including 82% reporting decreased exposure to urology. Nearly half of students reported changes to required rotations and 35% reported changes to urology-specific rotations at their home institutions. Students shared concerns about suspending in-person experiences, including the impact on letters of recommendation (68% “very concerned) and program choice (73% “very concerned”). Looking to the possibility of virtual interactions, students identified the importance of small group and one-on-one communication with residents (83% “very important”) and opportunities to learn about hospital facilities (72% “very important”).
Despite the impacts of COVID-19 on medical education, prospective urology applicants appear to remain confident in their specialty choice. Students’ biggest concerns involve disruption of away rotations, including impacts on obtaining letters of recommendation and choosing a residency program.
Neurofeedback – learning to modulate brain function through real-time monitoring of current brain state – is both a powerful method to perturb and probe brain function and an exciting potential ...clinical tool. For neurofeedback effects to be useful clinically, they must persist. Here we examine the time course of symptom change following neurofeedback in two clinical populations, combining data from two ongoing neurofeedback studies. This analysis reveals a shared pattern of symptom change, in which symptoms continue to improve for weeks after neurofeedback. This time course has several implications for future neurofeedback studies. Most neurofeedback studies are not designed to test an intervention with this temporal pattern of response. We recommend that new studies incorporate regular follow-up of subjects for weeks or months after the intervention to ensure that the time point of greatest effect is sampled. Furthermore, this time course of continuing clinical change has implications for crossover designs, which may attribute long-term, ongoing effects of real neurofeedback to the control intervention that follows. Finally, interleaving neurofeedback sessions with assessments and examining when clinical improvement peaks may not be an appropriate approach to determine the optimal number of sessions for an application.
•Temporal pattern of symptom change following neurofeedback shared across studies.•Symptoms continued to improve for weeks after neurofeedback.•Neurofeedback studies should follow up subjects to maximize power.•Crossover designs may be contaminated by significant carryover effects.•Optimizing number of sessions by embedding assessments not recommended.
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