Modified bubble level senses pitch and roll angles over wide range

Bubble level sensor with fiber-optic field flattener is simple, rugged, small, and impervious to temperature and vibration effects. Pitch angles from -15 deg to +40 deg and roll angles of +30 deg are determined within 0.5 deg

Polydisperse streaming instability – I. Tightly coupled particles and the terminal velocity approximation

We introduce a polydisperse version of the streaming instability, where the dust component is treated as a continuum of sizes. We show that its behaviour is remarkably different from the monodisperse streaming instability. We focus on tightly coupled particles in the terminal velocity approximation and show that unstable modes that grow exponentially on a dynamical time scale exist. However, for dust to gas ratios much smaller than unity they are confined to radial wave numbers that are a factor $\sim 1/\overline{\rm St}$ larger than where the monodisperse streaming instability growth rates peak. Here $\overline{\rm St} \ll 1$ is a suitable average Stokes number for the dust size distribution. For dust to gas ratios larger than unity, polydisperse modes that grow on a dynamical time scale are found as well, similar as for the monodisperse streaming instability and at similarly large wave numbers. At smaller wave numbers, where the classical monodisperse streaming instability shows secular growth, no growing polydisperse modes are found under the terminal velocity approximation. Outside the region of validity for the terminal velocity approximation, we have found unstable epicyclic modes that grow on $\sim 10^4$ dynamical time scales.Comment: 17 pages, 10 figures, 1 table. Submitte

The use of neighbourhood intensity comparisons, morphological gradients and Fourier analysis for automated precipitate counting & Pendell¨osung fringe analysis in X-ray topography

Crystal distortions modify the propagation of X-rays in single crystal materials, and X-ray topography can be used to record these modifications on a film thus providing images of the distributions and nature of defects, dislocations, strains, precipitates, etc. in semiconductors. Small variations of contrast, which often need to be analysed can be rendered invisible. Furthermore, artefacts in the films must be removed. This study examines the use of advanced image analysis techniques applied to a selection of X-ray topographs in section transmission mode: (i) the automated counting of oxygen-related precipitates and (ii) the enhancement of Pendell¨osung fringes. The technique also succeeds in removing unwanted features in the original x-ray topographs such as vertical streaking due to collimating slit phase contrast and strain features near the surface due to the presence of integrated circuit process strains

Phytoremediation as a Tool to Remove Drivers of Antimicrobial Resistance in the Aquatic Environment

Antimicrobials, heavy metals, and biocides are ubiquitous contaminants frequently detected in water bodies across the globe. These chemicals are known as drivers of antimicrobial resistance (AMR), as these chemicals can select for resistance. Tools and processes, are therefore, needed to remove these chemicals from the environment to tackle the environmental component of AMR. Aquatic phytoremediation is a nature-inspired green solution to remove contaminants from the environment. Phytoremediation utilises macrophytes’ ability to sequester and degrade chemical pollutants in aquatic environments. In this review, we define the problem statement by highlighting the presence of AMR drivers in the aquatic environment. We also provide an in-depth review of phytoremediation to tackle chemical pollution by evaluating mechanisms for the removal and degradation of chemicals. This review identifies potential hyper-accumulators and understands how plant species and chemical composition can influence the potential for accumulation. Different pollutants accumulate to different extents in a range of aquatic macrophytes. Therefore, the combined use of floating, submerged and emergent plants would facilitate the optimum removal of AMR drivers considered in this review. A suggested configuration includes Helianthus annus around the edge of a contaminated site, followed by a belt of submerged plants (Myriophyllum aquaticum) and a bed of floating plants (e.g., Lemna species) together with the hyperaccumulator, Phragmites australis. Whilst phytoremediation offers a promising option to treat contaminated water, several critical knowledge gaps still exist. The effect of co-exposure to contaminants on the accumulation potential of plants and the fate of antibiotic-resistant genes and bacteria during the phytoremediation process are highlighted in this review. Based on this understanding, targeted areas for future research are proposed

Space-time clustering analyses of childhood acute lymphoblastic leukaemia by immunophenotype

Space-time clustering analyses of acute lymphoblastic leukaemia in children, by immunophenotype, were carried out using a population-based registry. Significant evidence was found of space-time clustering for cases of the precursor B-cell sub-type, in the childhood peak, based on time and location at birth

Mapping gene-by-gene single-nucleotide variation in 8,535 <i>Mycobacterium tuberculosis</i> genomes:a resource to support potential vaccine and drug development

Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosisMycobacterium bovi

Information management in the facilities domain: investigating practitioner priorities

Purpose: Effective information management can help real estate operators improve asset performance during use, reducing environmental impact. The purpose of this exploratory study is to identify and prioritise key drivers, challenges and opportunities relating to information management, from the point of view of a diverse cohort of facilities practitioners, with the aim of guiding future research direction and contributing to a comprehensive domain understanding. Design/methodology/approach: Nine interviews are conducted across a broad sample of RE sectors, the respondents including six facility managers and three data managers. A thematic analysis results in the identification and ranking in terms of importance of 44 emergent themes. These themes are then grouped into abstracted categories for analysis and synthesis. Findings: This study indicates that systemic rather than technical issues are the greatest barrier to effective IM for facilities practitioners, the interviews providing examples of practical measures which address these challenges, promoting lifecycle thinking. Alignment is also found between the facilities and data management cohorts regarding lifecycle thinking towards both physical assets and information. Practical implications: This study provides direction for future developments in the facilities sector, suggesting the pursuit to address systemic issues as being both worthwhile and feasible. Originality/value: The novelty of this study is the ranking and synthesis of practitioner priorities with regard to high-level IM issues which is lacking in the literature, with a focus to-date on case-specific technical integration

Analysis of the impact of dislocation distribution on the breakdown voltage of GaAs-based power varactor diodes

A synchrotron x-ray topography analysis of the impact of the distribution of defects/dislocations on the electrical performance of GaAs power varactor diodes was carried out. Diodes fabricated on or near Liquid Encapsulated Czochralski cellular dislocation networks in the substrate, which are also known to be rich in As precipitates near these cell walls, were observed to have reduced breakdown voltages (VBR). This is consistent with the possibility that the presence of space-charge cylinders surrounding these dislocations gives rise to reduced VBR if they thread a p-n junction; it is also in accord with the possibility that the As precipitates themselves can act as sites for local field enhancement, thus promoting premature avalanche breakdown