In Situ Transmission X-Ray Microscopy of the Lead Sulfate Film Formation on Lead in Sulfuric Acid

Transmission X-ray microscopy is utilized to monitor, in real time, the behavior of the PbSO4 film that is formed on Pb in H2SO4. Images collected from the synchrotron x-rays are coupled with voltammetric data to study the initial formation, the resulting passivation, and the subsequent reduction of the film. It is concluded with support from quartz-crystal-microbalance experiments that the initial formation of PbSO4 crystals occurs as a result of acidic corrosion. In addition, the film is shown to coalesce during the early stages of galvanostatic oxidation and to passivate as a result of morphological changes in the existing film. Finally, it is observed that the passivation process results in the formation of large PbSO4 crystals with low area-to-volume ratios, which are difficult to reduce under both galvanostatic and potentiostatic conditions

Seroprevalence and risk factors for Neospora caninum in small dairy farms in central Chile

Indexación: Scopus.Objetivos. Proveer información sobre la seroprevalencia y factores de riesgo asociados a la infección por Neospora caninum en bovinos en Chile central. Materiales y métodos. La población estudiada corresponde a pequeñas lecherías que son parte de un programa gubernamental de Asistencia Técnica (SAT), en la región de O´Higgins en Chile central. Muestras de suero fueron recolectadas desde vacas en lactancia y analizadas mediante un kit comercial ELISA. Además, se aplicó un cuestionario a los dueños de los animales para la identificación de factores de riesgo a través de regresión logística. Resultados. Se identificó una prevalencia a nivel de granja del 67%, mientras que dentro de las granjas positivas, esta fue en promedio de 55%. El historial de abortos (p= 0.037, OR=5.09), la fuente de alimentación de perros (p= 0.0429, OR=6), la fuente de agua de bebida de las vacas (p=0.034, OR=4.5) y el manejo de los abortos (p=0.017, OR=7.43) fueron identificados como factores de riesgo para la infección. Conclusiones. Se observa una alta seroprevalencia de N. caninum en pequeños productores lecheros pertenecientes al SAT en Chile central. Los resultados presentados resaltan la necesidad de mejorar las acciones de vigilancia de esta enfermedad y el desarrollo de medidas preventivas para evitar las pérdidas asociadas a esta enfermedad.Objective. To provide information about seroprevalence and risk factors of Neospora caninum infection in bovines of central Chile. Material and Methods. The study population are small dairy farms that are part of a Government Technical Support Service (SAT) in the O'Higgins region in central Chile. Sera samples were collected from milking cows and analyzed by a commercial ELISA kit. Additionally, a questionnaire was applied to farmers to identify risk factors through logistic regression. Results. The farm level prevalence was found to be 67%, and within farms seroprevalence 55%. Abortion history (p= 0.037, OR=5.09), dogs feed source (p= 0.0429, OR=6), cattle drinking water source (p=0.034, OR=4.5) and abortions management (p=0.017, OR=7.43) were found as significant risk factors for infection. Conclusion. There is a high N. caninum seroprevalence in small SAT's dairy farms in O'Higgins region. These results highlight the need of improving N. caninum surveillance, and the development of preventive measures to avoid losses related with this disease.http://revistas.unicordoba.edu.co/index.php/revistamvz/article/view/92

Quantum-statistical transport phenomena in memristive computing architectures

The advent of reliable, nanoscale memristive components is promising for next generation compute-in-memory paradigms, however, the intrinsic variability in these devices has prevented widespread adoption. Here we show coherent electron wave functions play a pivotal role in the nanoscale transport properties of these emerging, non-volatile memories. By characterizing both filamentary and non-filamentary memristive devices as disordered Anderson systems, the switching characteristics and intrinsic variability arise directly from the universality of electron transport in disordered media. Our framework suggests localization phenomena in nanoscale, solid-state memristive systems are directly linked to circuit level performance. We discuss how quantum conductance fluctuations in the active layer set a lower bound on device variability. This finding implies there is a fundamental quantum limit on the reliability of memristive devices, and electron coherence will play a decisive role in surpassing or maintaining Moore's Law with these systems.Comment: 13 pages, 6 figure

Study Protocol - Alcohol Management Plans (AMPs) in remote indigenous communities in Queensland: their impacts on injury, violence, health and social indicators and their cost-effectiveness

BACKGROUND: In 2002/03 the Queensland Government responded to high rates of alcohol-related harm in discrete Indigenous communities by implementing alcohol management plans (AMPs), designed to include supply and harm reduction and treatment measures. Tighter alcohol supply and carriage restrictions followed in 2008 following indications of reductions in violence and injury. Despite the plans being in place for over a decade, no comprehensive independent review has assessed to what level the designed aims were achieved and what effect the plans have had on Indigenous community residents and service providers. This study will describe the long-term impacts on important health, economic and social outcomes of Queensland’s AMPs. METHODS/DESIGN: The project has two main studies, 1) outcome evaluation using de-identified epidemiological data on injury, violence and other health and social indicators for across Queensland, including de-identified databases compiled from relevant routinely-available administrative data sets, and 2) a process evaluation to map the nature, timing and content of intervention components targeting alcohol. Process evaluation will also be used to assess the fidelity with which the designed intervention components have been implemented, their uptake and community responses to them and their perceived impacts on alcohol supply and consumption, injury, violence and community health. Interviews and focus groups with Indigenous residents and service providers will be used. The study will be conducted in all 24 of Queensland’s Indigenous communities affected by alcohol management plans. DISCUSSION: This evaluation will report on the impacts of the original aims for AMPs, what impact they have had on Indigenous residents and service providers. A central outcome will be the establishment of relevant databases describing the parameters of the changes seen. This will permit comprehensive and rigorous surveillance systems to be put in place and provided to communities empowering them with the best credible evidence to judge future policy and program requirements for themselves. The project will inform impending alcohol policy and program adjustments in Queensland and other Australian jurisdictions.The study was funded by the National Health and Medical Research Council of Australia (NHMRC, Project Grant #APP1042532), with additional support from the Australian Primary Health Care Research Institute-funded Centre for Research Excellence for the Prevention of Chronic Conditions in Rural and Remote High Risk Populations at James Cook University & University Adelaide. Dr Caryn West is a National Health and Medical Research Council of Australia Early Career Research Post – Doctoral Fellow (NHMRC ECR, #APP1070931).Associate Professor Clough holds a NHMRC Career Development Award (#APP1046773)

Alcohol management plans in Aboriginal and Torres Strait Islander (Indigenous) Australian communities in Queensland: community residents have experienced favourable impacts but also suffered unfavourable ones

Background: In Australia, 'Alcohol Management Plans' (AMPs) provide the policy infrastructure for State and Commonwealth Governments to address problematic alcohol use among Aboriginal and Torres Strait Islanders. We report community residents' experiences of AMPs in 10 of Queensland's 15 remote Indigenous communities.\ud \ud Methods: This cross-sectional study used a two-stage sampling strategy: N = 1211; 588 (48%) males, 623 (52%) females aged ≥18 years in 10 communities. Seven propositions about 'favourable' impacts and seven about 'unfavourable' impacts were developed from semi-structured interviews. For each proposition, one-sample tests of proportions examined participant agreement and multivariable binary logistic regressions assessed influences of gender, age (18–24, 25–44, 45–64, ≥65 years), residence (≥6 years), current drinking and Indigenous status. Confirmatory factor analyses estimated scale reliability (ρ), item loadings and covariances.\ud \ud Results: Slim majorities agreed that: AMPs reduced violence (53%, p = 0.024); community a better place to live (54%, 0.012); and children were safer (56%, p < 0.001). More agreed that: school attendance improved (66%, p < 0.001); and awareness of alcohol's harms increased (71%, p < 0.001). Participants were equivocal about improved personal safety (53%, p = 0.097) and reduced violence against women (49%, p = 0.362). The seven 'favourable' items reliably summarized participants' experiences of reduced violence and improved community amenity (ρ = 0.90).\ud \ud Stronger agreement was found for six 'unfavourable' items: alcohol availability not reduced (58%, p < 0.001); drinking not reduced (56%, p < 0.001)); cannabis use increased (69%, p < 0.001); more binge drinking (73%, p < 0.001); discrimination experienced (77%, p < 0.001); increased fines, convictions and criminal records for breaching restrictions (90%, p < 0.001). Participants were equivocal (51% agreed, p = 0.365) that police could enforce restrictions effectively. 'Unfavourable' items were not reliably reflected in one group (ρ = 0.48) but in: i) alcohol availability and consumption not reduced and ii) criminalization and discrimination.\ud \ud In logistic regressions, longer-term (≥ 6 years) residents more likely agreed that violence against women had reduced and that personal safety had improved but also that criminalization and binge drinking had increased. Younger people disagreed that their community was a better place to live and strongly agreed about discrimination. Current drinkers' views differed little from the sample overall.\ud \ud Conclusions: The present Government review provides an opportunity to reinforce 'favourable' outcomes while targeting: illicit alcohol, treatment and diversion services and reconciliation of criminalization and discrimination issues.\ud \u

Delivering clinical studies of exercise in the COVID-19 pandemic: challenges and adaptations using a feasibility trial of isometric exercise to treat hypertension as an exemplar

The COVID-19 pandemic has significantly impacted on the delivery of clinical trials in the UK, posing complicated organisational challenges and requiring adaptations, especially to exercise intervention studies based in the community. We aim to identify the challenges of public involvement, recruitment, consent, follow-up, intervention and the healthcare professional delivery aspects of a feasibility study of exercise in hypertensive primary care patients during the COVID-19 pandemic. While these challenges elicited many reactive changes which were specific to, and only relevant in the context of ‘lockdown’ requirements, some of the protocol developments that came about during this unprecedented period have great potential to inform more permanent practices for carrying out this type of research. To this end, we detail the necessary adaptations to many elements of the feasibility study and critically reflect on our approach to redesigning and amending this ongoing project in order to maintain its viability to date. Some of the more major protocol adaptations, such as moving the study to remote means wherever possible, had further unforeseen and undesirable outcomes (eg, additional appointments) with regards to extra resources required to deliver the study. However, other changes improved the efficiency of the study, such as the remote informed consent and the direct advertising with prescreening survey. The adaptations to the study have clear links to the UK Plan for the future of research delivery. It is intended that this specific documentation and critical evaluation will help those planning or delivering similar studies to do so in a more resource efficient and effective way. In conclusion, it is essential to reflect and respond with protocol changes in the current climate in order to deliver clinical research successfully, as in the case of this particular study

Alcohol management plans in Aboriginal and Torres Strait Islander (Indigenous) Australian communities in Queensland: Community residents have experienced favourable impacts but also suffered unfavourable ones

Background: In Australia, ‘Alcohol Management Plans’ (AMPs) provide the policy infrastructure for State and Commonwealth Governments to address problematic alcohol use among Aboriginal and Torres Strait Islanders. We report community residents’ experiences of AMPs in 10 of Queensland’s 15 remote Indigenous communities. Methods: This cross-sectional study used a two-stage sampling strategy: N = 1211; 588 (48%) males, 623 (52%) females aged ≥18 years in 10 communities. Seven propositions about ‘favourable’ impacts and seven about ‘unfavourable’ impacts were developed from semi-structured interviews. For each proposition, one-sample tests of proportions examined participant agreement and multivariable binary logistic regressions assessed influences of gender, age (18–24, 25–44, 45–64, ≥65 years), residence (≥6 years), current drinking and Indigenous status. Confirmatory factor analyses estimated scale reliability (ρ), item loadings and covariances. Results: Slim majorities agreed that: AMPs reduced violence (53%, p = 0.024); community a better place to live (54%, 0.012); and children were safer (56%, p < 0.001). More agreed that: school attendance improved (66%, p < 0. 001); and awareness of alcohol’s harms increased (71%, p < 0.001). Participants were equivocal about improved personal safety (53%, p = 0.097) and reduced violence against women (49%, p = 0.362). The seven ‘favourable’ items reliably summarized participants’ experiences of reduced violence and improved community amenity (ρ = 0.90). Stronger agreement was found for six ‘unfavourable’ items: alcohol availability not reduced (58%, p < 0.001); drinking not reduced (56%, p < 0.001)); cannabis use increased (69%, p < 0.001); more binge drinking (73%, p < 0.001); discrimination experienced (77%, p < 0.001); increased fines, convictions and criminal records for breaching restrictions (90%, p < 0.001). Participants were equivocal (51% agreed, p = 0.365) that police could enforce restrictions effectively. ‘Unfavourable’ items were not reliably reflected in one group (ρ = 0.48) but in: i) alcohol availability and consumption not reduced and ii) criminalization and discrimination. In logistic regressions, longer-term (≥ 6 years) residents more likely agreed that violence against women had reduced and that personal safety had improved but also that criminalization and binge drinking had increased. Younger people disagreed that their community was a better place to live and strongly agreed about discrimination. Current drinkers’ views differed little from the sample overall. Conclusions: The present Government review provides an opportunity to reinforce ‘favourable’ outcomes while targeting: illicit alcohol, treatment and diversion services and reconciliation of criminalization and discrimination issues. Keywords: Alcohol, Indigenous, Aboriginal and Torres Strait Islander, Australian, Legal intervention, EvaluationThe study was funded by the National Health and Medical Research Council of Australia (NHMRC, Project Grant #APP1042532) with additional support from the Australian Primary Health Care Research Institute-funded Centre for Research Excellence for the Prevention of Chronic Conditions in Rural and Remote High Risk Populations at James Cook University & University Adelaide. Associate Professor Caryn West is a National Health and Medical Research Council of Australia Early Career Research Fellow (#APP1070931). Professor Clough holds a NHMRC Career Development Award (#APP1046773)

LSST Science Book, Version 2.0

A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over 20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a total point-source depth of r~27.5. The LSST Science Book describes the basic parameters of the LSST hardware, software, and observing plans. The book discusses educational and outreach opportunities, then goes on to describe a broad range of science that LSST will revolutionize: mapping the inner and outer Solar System, stellar populations in the Milky Way and nearby galaxies, the structure of the Milky Way disk and halo and other objects in the Local Volume, transient and variable objects both at low and high redshift, and the properties of normal and active galaxies at low and high redshift. It then turns to far-field cosmological topics, exploring properties of supernovae to z~1, strong and weak lensing, the large-scale distribution of galaxies and baryon oscillations, and how these different probes may be combined to constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at http://www.lsst.org/lsst/sciboo

Catching Element Formation In The Act

Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects and phenomena: stars, supernovae, novae, neutron stars, stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays and relativistic-particle acceleration, and the evolution of galaxies. MeV gamma-rays provide a unique probe of nuclear processes in astronomy, directly measuring radioactive decay, nuclear de-excitation, and positron annihilation. The substantial information carried by gamma-ray photons allows us to see deeper into these objects, the bulk of the power is often emitted at gamma-ray energies, and radioactivity provides a natural physical clock that adds unique information. New science will be driven by time-domain population studies at gamma-ray energies. This science is enabled by next-generation gamma-ray instruments with one to two orders of magnitude better sensitivity, larger sky coverage, and faster cadence than all previous gamma-ray instruments. This transformative capability permits: (a) the accurate identification of the gamma-ray emitting objects and correlations with observations taken at other wavelengths and with other messengers; (b) construction of new gamma-ray maps of the Milky Way and other nearby galaxies where extended regions are distinguished from point sources; and (c) considerable serendipitous science of scarce events -- nearby neutron star mergers, for example. Advances in technology push the performance of new gamma-ray instruments to address a wide set of astrophysical questions.Comment: 14 pages including 3 figure

The Fifth Data Release of the Sloan Digital Sky Survey

This paper describes the Fifth Data Release (DR5) of the Sloan Digital Sky Survey (SDSS). DR5 includes all survey quality data taken through June 2005 and represents the completion of the SDSS-I project (whose successor, SDSS-II will continue through mid-2008). It includes five-band photometric data for 217 million objects selected over 8000 square degrees, and 1,048,960 spectra of galaxies, quasars, and stars selected from 5713 square degrees of that imaging data. These numbers represent a roughly 20% increment over those of the Fourth Data Release; all the data from previous data releases are included in the present release. In addition to "standard" SDSS observations, DR5 includes repeat scans of the southern equatorial stripe, imaging scans across M31 and the core of the Perseus cluster of galaxies, and the first spectroscopic data from SEGUE, a survey to explore the kinematics and chemical evolution of the Galaxy. The catalog database incorporates several new features, including photometric redshifts of galaxies, tables of matched objects in overlap regions of the imaging survey, and tools that allow precise computations of survey geometry for statistical investigations.Comment: ApJ Supp, in press, October 2007. This paper describes DR5. The SDSS Sixth Data Release (DR6) is now public, available from http://www.sdss.or