Folner tilings for actions of amenable groups

We show that every probability-measure-preserving action of a countable amenable group G can be tiled, modulo a null set, using finitely many finite subsets of G ("shapes") with prescribed approximate invariance so that the collection of tiling centers for each shape is Borel. This is a dynamical version of the Downarowicz--Huczek--Zhang tiling theorem for countable amenable groups and strengthens the Ornstein--Weiss Rokhlin lemma. As an application we prove that, for every countably infinite amenable group G, the crossed product of a generic free minimal action of G on the Cantor set is Z-stable.Comment: Minor revisions. Final versio

Cost effectiveness of cascade testing for familial hypercholesterolaemia, based on data from familial hypercholesterolaemia services in the UK

Peer reviewedPublisher PD

Vine weeds in soybeans

"Vine weeds not only vigorously compete with crops, but they also plug up the combine and contribute to serious lodging. Once they are entangled in the soybean canopy, any attempt at cultivation strips foliage from the soybean plants. Severe infestations may cause 40 percent yield reduction. High moisture at harvest can also be a problem."--First page.Steve Livingston, L.E. Anderson, and Harold D. Kerr (Department of Agronomy, College of Agriculture)New 4/83/10

Liquid flow measurement using silicone polymer wedge clamp-on ultrasonic transducers

Accurate liquid flow measurement is vital to many industries, and the benefits and limitations of ultrasonic transit-time clamp-on measurements are well understood. The ultrasonic transducers used in high quality clamp-on systems tend to be high cost items, containing an ultrasonic wedge of machined polyether ether ketone plastic (PEEK). PEEK is used because of its consistency and favourable ultrasonic properties of relatively low attenuation and consistent ultrasonic wave velocity over a wide range of frequencies. The viability of a new, high performance and low cost design of clamp-on ultrasonic transducers is described, made from a silicone based polymer moulded inside a shell and directly bonded to the active piezoelectric element. In addition to the reduced material and production cost, the new transducers have good thermal stability, consistency, conform well to the surface of the pipe. Tests were performed on a flow rig and on calibration blocks for thermal stability tests, showing that the sensors are of comparable performance to quality devices constructed using PEEK wedges

Volumes and bulk densities of forty asteroids from ADAM shape modeling

Disk-integrated photometric data of asteroids do not contain accurate information on shape details or size scale. Additional data such as disk-resolved images or stellar occultation measurements further constrain asteroid shapes and allow size estimates. We aim to use all available disk-resolved images of about forty asteroids obtained by the Near-InfraRed Camera (Nirc2) mounted on the W.M. Keck II telescope together with the disk-integrated photometry and stellar occultation measurements to determine their volumes. We can then use the volume, in combination with the known mass, to derive the bulk density. We download and process all asteroid disk-resolved images obtained by the Nirc2 that are available in the Keck Observatory Archive (KOA). We combine optical disk-integrated data and stellar occultation profiles with the disk-resolved images and use the All-Data Asteroid Modeling (ADAM) algorithm for the shape and size modeling. Our approach provides constraints on the expected uncertainty in the volume and size as well. We present shape models and volume for 41 asteroids. For 35 asteroids, the knowledge of their mass estimates from the literature allowed us to derive their bulk densities. We clearly see a trend of lower bulk densities for primitive objects (C-complex) than for S-complex asteroids. The range of densities in the X-complex is large, suggesting various compositions. Moreover, we identified a few objects with rather peculiar bulk densities, which is likely a hint of their poor mass estimates. Asteroid masses determined from the Gaia astrometric observations should further refine most of the density estimates.Comment: Accepted for publication in A&

Stock Identification Methods Working Group (SIMWG)

The Stock Identification Methods Working Group (SIMWG) reviews new methods for the defi-nition and investigation of stock structure and provides advice to other ICES expert groups on how to interpret patterns of population structure. The identification of the spatial boundaries of exploited stocks is a fundamental requirement before any stock assessment or modelling can be contemplated, and therefore lies at the heart of resource management. SIMWG continues to provide annual updates on recent applications of stock identification methods to species assessed by ICES and on advances in stock identification methods. Based on the wide expertise of SIMWG members, the group provides reviews of recent literature on genetics, growth marks in calcified structures, life history parameters, morphometrics/ me-ristics, tagging, otolith shape, otolith chemistry, parasites and interdisciplinary approaches. A key activity of SIMWG is to address requests by ICES working groups for technical advice on issues of stock identity. In 2020, the working group reviewed the outcome of the Workshop on Stock Identification of North Sea Cod (WKNSCodID). SIMWG contributes to the general understanding of the biological features of the north Atlantic ecosystem through its work to describe fish population structure. Additionally, SIMWG’s annual reviews on advances in stock identification methods keeps ICES members abreast of best prac-tices in this field of study. SIMWG expert reviews on questions of stock structure for particular ICES species are directly relevant to the appropriate definition of stock and contribute to the accuracy of stock assessment and effectiveness of management actions. We see an important role for SIMWG in the future as ICES copes with the shifting distributions of fishery resources and questions regarding the appropriate definition of fish stocks. Understanding stock structure is a fundamental requirement before any assessment or modelling on a stock can be contemplated and SIMWG will continue to work with ICES expert groups to address pressing stock identifica-tion issues

A robotic exploration mission to Mars and Phobos

This report discusses the design of a robotic exploration to Mars and Phobos. It begins with the mission's background and objectives, followed by a detailed explanation of various elements of Project Aeneas, including science, spacecraft, probes, and orbital trajectories. In addition, a description of Argos Space Endeavours, management procedures, and overall project costs are presented. Finally, a list of recommendations for future design activity is included