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Evidence of Late Triassic large tetrapods from the UK is rare. Here, we describe a track-bearing surface located on the shoreline near Penarth, south Wales, United Kingdom. The total exposed surface is c. 50 m long and c. 2 m wide, and is split into northern and southern sections by a small fault. We interpret these impressions as tracks, rather than abiogenic sedimentary structures, because of the possession of marked displacement rims and their relationship to each other with regularly spaced impressions forming putative trackways. The impressions are large (up to c. 50 cm in length), but poorly preserved, and retain little information about track-maker anatomy. We discuss alternative, plausible, abiotic mechanisms that might have been responsible for the formation of these features, but reject them in favour of these impressions being tetrapod tracks. We propose that the site is an additional occurrence of the ichnotaxon Eosauropus, representing a sauropodomorph trackmaker, thereby adding a useful new datum to their sparse Late Triassic record in the UK. We also used historical photogrammetry to digitally map the extent of site erosion during 2009–2020. More than 1 m of the surface exposure has been lost over this 11-year period, and the few tracks present in both models show significant smoothing, breakage and loss of detail. These tracks are an important datapoint for Late Triassic palaeontology in the UK, even if they cannot be confidently assigned to a specific trackmaker. The documented loss of the bedding surface highlights the transient and vulnerable nature of our fossil resources, particularly in coastal settings, and the need to gather data as quickly and effectively as possible.
Systemic ventricular end-diastolic pressure is an important haemodynamic variable in adult patients with Fontan circulation. Risk factors associated with elevated end-diastolic pressure have not been clearly identified in this population.
All patients > 18 years with Fontan circulation who underwent cardiac catheterisation at our centre between 1/08 and 3/19 were included. Relevant patient variables were extracted. Univariate and multivariate general linear models were analysed to identify variables associated with end-diastolic pressure.
Forty-two patients were included. Median age was 24.0 years (20.9–29.0) with a body mass index of 23.7 kg/m2 (21.5–29.7). 10 (23.8%) patients had a systemic right ventricle. The median (Interquartile range) and mean pulmonary artery pressure were 11.0 mmHg (9.0–12.0) and 16.0 mmHg (13.0–18.0), respectively. On univariate analysis, end-diastolic pressure was positively associated with body mass index (p < 0.01), age > 25 years (p = 0.04), symptoms of heart failure (p < 0.01), systemic ventricular systolic pressure (p = 0.03), pulmonary artery mean pressure (p < 0.01), and taking diuretics (p < 0.01) or sildenafil (p < 0.01). End-diastolic pressure was negatively associated with aortic saturation (p < 0.01). On multivariate analysis, end-diastolic pressure was positively associated with age ≥ 25 years (p < 0.01), and body mass index (p = 0.04).
In a cohort of adult patients with Fontan circulation undergoing catheterisation, end-diastolic pressure was positively associated with age ≥ 25 years and body mass index on multivariate analysis. Maintaining a healthy body mass index may offer haemodynamic benefit in adults with Fontan physiology.
The regulation of mutual funds in the United States arguably contains the world’s most extensive system of fiduciary protection, buttressed by elaborate liability rules and a host of procedural protections and mandatory disclosure requirements designed to facilitate investor protection and choice. The intensity of this regulatory structure is a subject of perennial debate, as officials and analysts attempt to balance the cost of compliance and oversight against benefits to investors. Government officials have made numerous accommodations to ameliorate the system’s costs and facilitate industry innovations. But, the burdens of this enhanced system of fiduciary protections for mutual funds remain significant and have encouraged industry participants to evade these legal requirements in a number of ways, such as the creation of alternative vehicles for collective investments and the imbedding of regulated mutual funds into other legal structures that escape the full application of the enhanced system of fiduciary protections for mutual funds. This chapter suggests areas where aspects of mutual fund regulation might appropriately be extended to functionally similar investment vehicles.
Smart contracts have been proposed as a means of revolutionizing transacting between human actors and contributing to blockchain platforms substituting for many current institutions. However, the technical nature of blockchain platforms and smart contracts requires levels of certainty and foresight sufficient for contracts to be complete. We examine the technical and economic characteristics of blockchains and smart contracts to identify sources of uncertainty that may pose challenges to the ability of these technologies to displace existing institutional arrangements, in particular, the courts and other arbitration arrangements. Despite the development of alternative automated blockchain institutions such as the Kleros dispute resolution system, the case for smart contracts and blockchain applications to supplant real-world institutions remains weak. Inherent incompleteness due to limits to information availability, human cognition, and communication means that traditional contract governance institutions will continue to complement blockchain smart contract governance arrangements. The more complex and unique the transaction, the higher the value at risk, the harder to anticipate and precisely specify contingencies and measure and observe outcomes. Furthermore, the longer the time frame between agreement and execution, the less likely it is that smart contracting will be more efficient than traditional contracting.
People with neurodevelopmental disorders often present with challenging behaviours and psychiatric illnesses. Diagnosis and treatment require patients, families and healthcare professionals to work closely together in partnership, acknowledging their respective areas of expertise. Good treatment outcomes should also be underpinned by robust research evidence. Key research priorities are highlighted.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Mollusc seashells grow through the local deposition and calcification of material at the shell opening by a soft and thin organ called the mantle. Through this process, a huge variety of shell structures are formed. Previous models have shown that these structural patterns can largely be understood by examining the mechanical interaction between the deformable mantle and the rigid shell aperture to which it adheres. In this paper we extend this modelling framework in two distinct directions. For one, we incorporate a mechanical feedback in the growth of the mollusc. Second, we develop an initial framework to couple the two primary and orthogonal modes of pattern formation in shells, which are termed antimarginal and commarginal ornamentation. In both cases we examine the change in shell morphology that occurs due to the different mechanical influences and evaluate the hypotheses in light of the fossil record.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
In 2013, New York State mandated that, during influenza season, unvaccinated healthcare personnel (HCP) wear a surgical mask in areas where patients are typically present. We found that this mandate was associated with increased HCP vaccination and decreased HCP visits to the hospital Workforce Health and Safety Department with respiratory illnesses and laboratory-confirmed influenza.
The Zadko telescope is a 1 m f/4 Cassegrain telescope, situated in the state of Western Australia about 80-km north of Perth. The facility plays a niche role in Australian astronomy, as it is the only meter class facility in Australia dedicated to automated follow-up imaging of alerts or triggers received from different external instruments/detectors spanning the entire electromagnetic spectrum. Furthermore, the location of the facility at a longitude not covered by other meter class facilities provides an important resource for time critical projects. This paper reviews the status of the Zadko facility and science projects since it began robotic operations in March 2010. We report on major upgrades to the infrastructure and equipment (2012–2014) that has resulted in significantly improved robotic operations. Second, we review the core science projects, which include automated rapid follow-up of gamma ray burst (GRB) optical afterglows, imaging of neutrino counterpart candidates from the ANTARES neutrino observatory, photometry of rare (Barbarian) asteroids, supernovae searches in nearby galaxies. Finally, we discuss participation in newly commencing international projects, including the optical follow-up of gravitational wave (GW) candidates from the United States and European GW observatory network and present first tests for very low latency follow-up of fast radio bursts. In the context of these projects, we outline plans for a future upgrade that will optimise the facility for alert triggered imaging from the radio, optical, high-energy, neutrino, and GW bands.
Two-sided oxidation experiments were recently conducted at 1000-1200°C in flowing steam with samples of sponge-based Zr-1Nb alloy E110. Although the old electrolytic E110 tubing exhibited a high degree of susceptibility to nodular corrosion and experienced breakaway oxidation rates in relatively short time, the new sponge-based E110 has demonstrated steam oxidation behavior comparable to Zircaloy-4. The sponge-based E110 followed the parabolic law, and the derived oxidation rate constant is in good agreement with the Cathcart-Pawel (CP) correlation at 1100-1200°C. For 1000°C oxidation, the weight-gain of sponge-based E110 is much lower than Zircaloy-4. No breakaway oxidation was observed at 1000°C up to 8000 s. Ring compression tests were conducted to evaluate the residual ductility of oxidized samples at room temperature and at 135°C. All sponge-based E110 specimens were still ductile at 135°C after being oxidized up to 20% equivalent cladding reacted at 1000-1200°C. Metallographic examinations were performed on oxidized E110 specimens to correlate material performance with microstructure.
The first observations by a worldwide network of advanced interferometric gravitational wave detectors offer a unique opportunity for the astronomical community. At design sensitivity, these facilities will be able to detect coalescing binary neutron stars to distances approaching 400 Mpc, and neutron star–black hole systems to 1 Gpc. Both of these sources are associated with gamma-ray bursts which are known to emit across the entire electromagnetic spectrum. Gravitational wave detections provide the opportunity for ‘multi-messenger’ observations, combining gravitational wave with electromagnetic, cosmic ray, or neutrino observations. This review provides an overview of how Australian astronomical facilities and collaborations with the gravitational wave community can contribute to this new era of discovery, via contemporaneous follow-up observations from the radio to the optical and high energy. We discuss some of the frontier discoveries that will be made possible when this new window to the Universe is opened.
In this paper, we consider the straining flow of a weakly interacting polymer–surfactant solution below a free surface, with the bulk surfactant concentration above the critical micelle concentration. We formulate a set of coupled differential equations describing the concentration of monomers, micelles, polymer, and polymer–micelle aggregates in the flow. We analyse the model in several asymptotic limits, and make predictions about the distribution of each of the species. In particular, in the large-reaction-rate limit we find that the model predicts a region near the free surface where no micelles or aggregates are present, and beneath this a region where the concentration of surfactant is constant, across which the concentration of aggregates increases until all the free polymer is consumed. For certain parameter regimes, a maximum in the concentration of the polymer–micelle complex occurs within the bulk fluid. In the finite-reaction-rate limit, micelles, and aggregates are present right up to the free surface, and the plateau in the concentration of surfactant in the bulk is no longer present. Results from the asymptotic theory compare favorably with full numerical solutions.
To evaluate Medical Reserve Corps volunteers and public health workers in conducting chronic care triage by use of a rubric prior to sheltering to connect survivors with services.
Participants were randomly assigned to 1 of 3 algorithms or a control group during a simulated disaster scenario and were asked to rate 20 survivors arriving at a chronic care triage station with situation-appropriate transport services. Survivors were simulated on the basis of the expected disability distributions of mobility, sensory-visual, cognition, medical devices, capacity to perform activities of daily living (ADLs), age (18 to 90 years), weight, and gender expected in the general population but expanded to 90% of those presenting. Mean percentage correct scores were assessed by using one-way analysis of variance.
Accounting for personal care assistance and service methodology during chronic care triage increased efficiency by up to 8% in meeting chronic care health service needs during disaster community mass care management.
A chronic care triage process as part of community mass care management that considers the availability of personal care assistance and service methodology will enhance the allocation of functional needs support services and increase compliance with Americans with Disabilities Act requirements regarding not segregating persons because of disability. (Disaster Med Public Health Preparedness. 2015;9:265-274)
Herbicides inhibit biochemical and physiological processes or both with lethal consequences. The target sites of these small molecules are usually enzymes involved in primary metabolic pathways or proteins carrying out essential physiological functions. Herbicides tend to be highly specific for their respective target sites and have served as tools to study these physiological and biochemical processes in plants (Dayan et al. 2010b).