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A Canadian health authority implemented a multisectoral intervention designed to control severe acute respiratory coronavirus virus 2 (SARS-CoV-2) transmission during long-term care facility (LTCF) outbreaks. The primary objective was to evaluate the effectiveness of the intervention 14 days after implementation.
A series of outbreak measures classified into 4 categories: case and contact management, proactive case detection, rigorous infection control practices and resource prioritization and stewardship.
A mixed-effects segmented Poisson regression model was fitted to the incidence rate of coronavirus disease 2019 (COVID-19), calculated every 2 days, within each facility and case type (staff vs residents). For each facility, the outbreak time period was segmented into an early outbreak period (within 14 days of the intervention) and postintervention period (beyond 14 days following the intervention). Model outputs quantified COVID-19 incidence trend and rate changes between these 2 periods. A secondary model was constructed to identify effect modification by case type.
The significant upward trend in COVID-19 incidence rate during the early outbreak period (rate ratio [RR], 1.07; 95% confidence interval [CI], 1.03–1.11; P < .001) reversed during the postintervention period (RR, 0.73; 95% CI, 0.67–0.80; P < .001). The average trend did not differ by case type during the early outbreak period (P > .05) or the postintervention period (P > .05). However, staff had a 70% larger decrease in the average rate of COVID-19 during the postintervention period than residents (RR, 0.30; 95% CI, 0.10–0.88; P < .05).
Our study provides evidence for the effectiveness of this intervention to reduce the transmission of COVID-19 in LTCFs. This intervention can be adapted and utilized by other jurisdictions to protect the vulnerable individuals in LTCFs.
New Zealand's ageing population and health inequities for Māori (Indigenous peoples) have prompted calls for innovative, culturally based approaches to improving health and wellbeing, and managing transitions in later life. This is particularly important for kaumātua (Māori elders) who, despite cultural strength and resilience, carry a significant burden in health, economic and social inequities. This paper describes the culture-centred development of a ‘tuakana‒teina’ (elder sibling‒younger sibling) peer support education programme designed to help kaumātua support other kaumātua experiencing transitions in later life. Taking a strengths-based approach that highlights ‘kaumātua mana motuhake’ (elder independence and autonomy), the study used kaupapa Māori (Māori approach, knowledge, skills, attitudes and values) and community-based participatory research methodology, to develop and pilot a culture-centred tuakana‒teina/peer education programme. Methods included establishing two advisory groups (one of kaumātua and one of sector experts); holding five focus groups with kaumātua; and running a pilot programme with 21 kaumātua. The findings demonstrate the value in a strengths-based approach that centralises Māori culture and kaumātua potential, capacity and ability, and recognises the continuing value and contribution of kaumātua to society. The study helps shift the focus from dominant stereotypes of ageing populations as a burden on society and shows the value of kaumātua supporting others during transitions in later life.
The end of the last Ice Age in Britain (c. 11500 BP) created major disruption to the biosphere. Open habitats were succeeded by more wooded landscapes, and changes occurred to the fauna following the abrupt disappearance of typical glacial herd species, such as reindeer and horse (Conneller & Higham 2015). Understanding the impact of these changes on humans and how quickly they were able to adapt may soon become clearer, due to recent discoveries in the Colne Valley on the western edge of Greater London, north of the River Thames. An exceptionally well-preserved open-air site was discovered in 2014 as part of a wider project of archaeological investigation and excavation carried out by Wessex Archaeology (2015), on behalf of CEMEX UK. The site, at Kingsmead Quarry in Horton, is unusual because it has good organic preservation and, in addition to worked flint artefacts, it has yielded groups of articulated horse bone. The extreme rarity of such sites of this period in Britain makes this discovery especially significant and re-emphasises the potential importance of the Colne Valley (Lacaille 1963; Lewis 2011; Morgi et al. 2011).
This paper describes the discovery of a massive, fan-shaped flint core from West Kennett Farm, near Avebury in Wiltshire, a site that is noted for two Late Neolithic palisaded enclosures. The discovery of the core has renewed focus on three similar artefacts from East Anglia, the importance of which has been overlooked. These cores arguably constitute some of the largest individual pieces of systematically worked flint from Britain. The paper considers the implications of the discovery at West Kennett Farm, where nodules of this size are absent, with the movement of flint across Britain, and concludes by discussing the role of these ‘mega-cores’ with current thinking on the function of stone in Neolithic Britain.
Calculations based on Poisson-Boltzmann theory are used to investigate the equilibrium properties of an electrolyte containing TcO4− and SO42− ions near the surface of amorphous silica. The calculations show that the concentration of TcO4− is greater than SO42− at distances less than 1 nm from the surface due to the negative charge density caused by deprotonation of the amorphous silica silanol groups. At lower pH, the surface becomes protonated and the magnitude of this effect is reduced. These results have implications for the potential use of oxyanion-SAMMS for the environmental remediation of water contaminated with 99Tc.
The results of sequential large-scale molecular dynamics (MD) simulations of radiation damage cascades in Gd2Ti2O7 and Gd2Zr2O7 are presented. Twelve alpha recoil cascades, each due to a recoil atom with 40 keV of kinetic energy, are performed in both materials and a stark contrast in behaviour observed. Topological connectivity analysis is used to analyse the structural evolution of the two systems. Our results provide important insight into accumulation of disorder in pyrochlore-structured ceramics.
Nitridation is the process in which, during the initial growth of a-SiNx:H layers on Si surfaces, nitrogen (N) is incorporated into Si lattice near its surface. We show that this nitridation process affects the density of interface states (Dit) and fixed charges (Qf) at the interface. These parameters determine the effective surface passivation quality of the layers. The nitridation can be tuned independently of the growth of a-SiNx:H layers by using a plasma treatment prior to actual a-SiNx:H layer deposition. It is shown that the Qf can be varied from 2·1012 to 15·1012 cm-2 without changing the a-SiNx:H deposition process. It is demonstrated that in our case and processing window, Qf is the determining factor in surface passivation quality in the range of 2·1012 to 8·1012 cm-2. For higher values of Qf, Dit has increased significantly and has become dominant thereby reducing the passivation quality. It is shown that the passivation can be controlled independently of the a-SiNx:H deposition process. On completed solar cells this variation in Qf due to nitridation results in a change in open-circuit voltage, Voc, of almost 20mV.
This study investigates whether investors see through materially misstated earnings, and whether they anticipate earnings restatements. For firms that restate at least one annual report, we find that investors are misled by mistakes in reported earnings at the time of initial earnings announcements. Investors react positively to the component of the favorable earnings surprise that will subsequently be restated, and they attach the same valuation to it as to the true earnings surprise. We also find that investors anticipate the subsequent downward restatements and start marking stock prices down several months before a restatement announcement, so that the full impact of a restatement is about three times as large as the restatement announcement effect. Indeed, we show that investors punish restating firms because the stock price gains that shareholders enjoy when firms initially announce overstated earnings are more than reversed by the time of the restatement announcement.
Prompted by renewed interest in the crystalline oxides-on-semiconductors interface, periodic density functional theory and atomistic simulation techniques are used to examine the formation of a layer of CaO on a BaO substrate. We examine how CaO islands which form at coverages less than 100% adjust to the substrate in which the cation-anion separation is substantially larger than in CaO itself. All Ca-O bond lengths in the island are shorter than that in bulk CaO. Corner O atoms in the islands are associated with particularly short Ca-O bond lengths, and the shape of the islands is dominated by (100) edges. Once formed, islands with intact edges will remain intact. Interactions between islands at larger coverages are also investigated and we see the formation of characteristic elliptical gaps and loops.
Results of periodic ab initio density functional theory calculations on thin films of (i) wurtzite ZnO (hexagonal) which terminate with the non-polar (1010) surface, and with the polar (0001) and (0001) surfaces (ii) zinc blende (cubic) ZnO which terminate with the non-polar (110) and with the polar (111) surfaces. Thin (less than18 layer) films of wurtzite ZnO which terminate with the polar (0001) and (0001) surfaces are found to be higher in energy than corresponding films in which these polar surfaces flatten out forming a new planar ‘graphitic’-like structure in which the Zn and O atoms are coplanar and the dipole is removed. This is the lowest energy surface for ultra-thin films. For zinc-blende ZnO a graphitic-type solution, but with a different stacking of ZnO layers, is also comparable to energy to the non-polar (110) and polar (111) solutions. Consequences for crystal growth and the stabilization of thin films and nanostructures are discussed.
We give an update of our ongoing survey for intracluster light (ICL), in a sample of distant Abell clusters. We find that the amount of intracluster starlight is comparable to that seen in nearby clusters, and that tidal debris appear to be common.
Experiments have shown that ordered monolayers of large organic molecules can control crystal nucleation and growth. The work of nucleation controls which morphology and phase will appear. We have used molecular dynamics to simulate the interfaces between stearic acid and a number of calcium carbonate surfaces. An important issue is the ionisation state of the acid which depends on the pH of the solution at the surface. We estimate this by solving the nonlinear Grahame equation for a calcium carbonate solution. The species in solution are chosen from geochemical models. The calculated interfacial binding energy between monolayer and material is often of the order of 1 Jm-2, suggesting that the nucleation rate is strongly enhanced.
Interfaces can be considered at a variety of length scales. All interfaces except grain boundaries are dielectric interfaces. In many cases, the geometric constraints of matching two lattices must be considered, together with the misfit strains that are often present. Continuum mechanics is useful for tackling such problems. In many cases, however, the local ordering of ions must also be considered. Atomistic simulation is therefore necessary, together with the problems associated with large length scales and long time scales. We discuss a number of examples to illustrate the issues involved and the compromises between different approaches that must be made.
The origins of the probation service can be traced back to the late-Victorian era and the introduction of the so-called police court missionaries who supervised offenders on conditional release from the court. The service grew slowly, but mushroomed in the 1970s and 1980s when several major acts widened the scope of the service by introducing parole, aftercare of discharged prisoners, community service by offenders, and extended the scope of probation and bail hostels. Since the beginning of this decade the probation service has been working in an ever-changing legal and philosophical context. Public protection and the prevention of crime are our primary aims. Legislation and ministerial directives have necessitated increasing involvement of probation offices in work with offenders with mental disorder, and have brought into greater focus the relationship of the probation service with psychiatry.
Research and development in the German economy is internationalising: recently there has been an increase in outward DFI by German companies relative to the inward DFI of foreign-owned companies in Germany. By examining the long term trends in patents granted in the USA to the world's largest firms between 1969 and 1995, it emerges that Germany is now catching-up with a world-wide trend to internationalise technological activaty, and has done this on the basis of its core technological strengths developed historically at a national and corporate level. The research and innovation infrastructure of the economy remains strong, and German companies are locating abroad in the industries which are the most science-based, which are supportive of domestically-based core technologies and in which they hold the strongest competitive position relative to other European firms. German-owned companies retain their dominance of German-located R & D in five key industries—electronics, chemicals, pharmaceuticals, metals and motor vehicles—and they have developed technological specialisms clearly focused on the core technologies of these industries, at home and now also abroad.