Dynamics of Perfectly Wetting Drops under Gravity

We study the dynamics of small droplets of polydimethylsiloxane (PDMS) silicone oil on a vertical, perfectly-wetting, silicon wafer. Interference videomicroscopy allows us to capture the dynamics of these droplets. We use droplets with a volumes typically ranging from 100 to 500 nanolitres (viscosities from 10 to 1000 centistokes) to understand long time derivations from classical solutions. Past researchers used one dimensional theory to understand the typical $t^{1/3}$ scaling for the position of the tip of the droplet in time $t$. We observe this regime in experiment for intermediate times and discover a two-dimensional, similarity solution of the shape of the droplet. However, at long times our droplets start to move more slowly down the plane than the $t^{1/3}$ scaling suggests and we observe deviations in droplet shape from the similarity solution. We match experimental data with simulations to show these deviations are consistent with retarded van der Waals forcing which should become significant at the small heights observed

Detection of Clostridium difficile infection clusters, using the temporal scan statistic, in a community hospital in southern Ontario, Canada, 2006–2011

BACKGROUND: In hospitals, Clostridium difficile infection (CDI) surveillance relies on unvalidated guidelines or threshold criteria to identify outbreaks. This can result in false-positive and -negative cluster alarms. The application of statistical methods to identify and understand CDI clusters may be a useful alternative or complement to standard surveillance techniques. The objectives of this study were to investigate the utility of the temporal scan statistic for detecting CDI clusters and determine if there are significant differences in the rate of CDI cases by month, season, and year in a community hospital. METHODS: Bacteriology reports of patients identified with a CDI from August 2006 to February 2011 were collected. For patients detected with CDI from March 2010 to February 2011, stool specimens were obtained. Clostridium difficile isolates were characterized by ribotyping and investigated for the presence of toxin genes by PCR. CDI clusters were investigated using a retrospective temporal scan test statistic. Statistically significant clusters were compared to known CDI outbreaks within the hospital. A negative binomial regression model was used to identify associations between year, season, month and the rate of CDI cases. RESULTS: Overall, 86 CDI cases were identified. Eighteen specimens were analyzed and nine ribotypes were classified with ribotype 027 (n = 6) the most prevalent. The temporal scan statistic identified significant CDI clusters at the hospital (n = 5), service (n = 6), and ward (n = 4) levels (P ≤ 0.05). Three clusters were concordant with the one C. difficile outbreak identified by hospital personnel. Two clusters were identified as potential outbreaks. The negative binomial model indicated years 2007–2010 (P ≤ 0.05) had decreased CDI rates compared to 2006 and spring had an increased CDI rate compared to the fall (P = 0.023). CONCLUSIONS: Application of the temporal scan statistic identified several clusters, including potential outbreaks not detected by hospital personnel. The identification of time periods with decreased or increased CDI rates may have been a result of specific hospital events. Understanding the clustering of CDIs can aid in the interpretation of surveillance data and lead to the development of better early detection systems

Transforming LIS Education through Disability Inclusion

Combining perspectives from Australia, Canada, New Zealand, and the US, this international panel will develop an honest dialog on disability inclusion in LIS education, drawing on empirical research, discursive analysis, and practical experience. All introductory talks will be followed by nuanced and carefully developed experiential activities prepared by each group of presenters and delivered at the two thematically arranged round tables. Jointly, seven interconnected presentations will address LIS pedagogy, educational policy, and educational content from the standpoint of disability inclusion and its potential to transform LIS education

A Pathway to Precision Medicine for Aboriginal Australians: A Study Protocol

Published: 21 June 2021(1) Background: Genomic precision medicine (PM) utilises people’s genomic data to inform the delivery of preventive and therapeutic health care. PM has not been well-established for use with people of Aboriginal and Torres Strait Islander ancestry due to the paucity of genomic data from these communities. We report the development of a new protocol using co-design methods to enhance the potential use of PM for Aboriginal Australians. (2) Methods: This iterative qualitative study consists of five main phases. Phase-I will ensure appropriate governance of the project and establishment of a Project Advisory Committee. Following an initial consultation with the Aboriginal community, Phase-II will invite community members to participate in co-design workshops. In Phase-III, the Chief Investigators will participate in co-design workshops and document generated ideas. The notes shall be analysed thematically in Phase-IV with Aboriginal community representatives, and the summary will be disseminated to the communities. In Phase-V, we will evaluate the co-design process and adapt our protocol for the use in partnership with other communities. (3) Discussion: This study protocol represents a crucial first step to ensure that PM research is relevant and acceptable to Aboriginal Australians. Without fair access to PM, the gap in health outcome between Aboriginal and non-Aboriginal Australians will continue to widen.Yeu-Yao Cheng, Jack Nunn, John Skinner, Boe Rambaldini, Tiffany Boughtwood, Tom Calma, Alex Brown, Cliff Meldrum, Marcel E. Dinger, Jennifer A. Byrne, Debbie McCowen, Jayden Potter, Kerry Faires, Sandra Cooper and Kylie Gwynn

Un modelo predictivo de la evolución en costas rocosas.

El retroceso de las costas acantiladas es un fenómeno muy extendido sobre los litorales rocosos expuestos a la incidencia combinada de los procesos marinos y meteorológicos que se dan en la franja costera. Este fenómeno se revela violentamente como movimientos gravitacionales del terreno esporádicos, pudiendo causar pérdidas materiales y/o humanas. Aunque el conocimiento de estos riesgos de erosión resulta de vital importancia para la correcta gestión de la costa, su predicción es complicada. Los modelos de predicción publicados son escasos y con importantes inconvenientes: extrapolación, extienden información registros históricos; empíricos, sobre registros históricos estudian respuesta al cambio de un parámetro; estocásticos, determinan la cadencia y magnitud de los eventos futuros extrapolando las distribuciones de probabilidad extraídas de catálogos históricos; proceso-respuesta, de estabilidad y propagación del error inexplorada; en EDPs, computacionalmente costosos y poco exactos. En este trabajo se desarrolla un modelo combinado de proceso-respuesta basado en incorporar un balance de fuerzas de los mecanismos que actúan sobre el proceso erosivo en el frente del acantilado. El modelo simula la evolución espacio-temporal de un perfil-2D del acantilado, formado por materiales heterogéneos, acoplando la dinámica marina con la evolución del terreno en cada periodo de marea. Integra en cada periodo una función de erosión, dependiente de la pendiente de la zona afectada, que se desplaza sobre la onda de marea. Se ha estudiado el error de discretización del modelo y su propagación en el tiempo a partir de las soluciones exactas para los dos primeros periodos de marea para diferentes aproximaciones numéricas en la integración y de la pendiente. Los resultados obtenidos han permitido justificar las discretizaciones que minimizan el error y los métodos de aproximación más adecuados