Fabrication of high quality plan-view TEM specimens using the focused ion beam

We describe a technique using a focused ion beam instrument to fabricate high quality plan-view specimens for transmission electron microscopy studies. The technique is simple, site-specific and is capable of fabricating multiple large, >100 μm2 electron transparent windows within epitaxially-grown thin films. A film of La0.67Sr0.33MnO3 is used to demonstrate the technique and its structural and functional properties are surveyed by high resolution imaging, electron spectroscopy, atomic force microscopy and Lorentz electron microscopy. The window is demonstrated to have good thickness uniformity and a low defect density that does not impair the film’s Curie temperature. The technique will enable the study of in–plane structural and functional properties of a variety of epitaxial thin film systems

Individual isotopic specializations predict subsequent inter-individual variation in movement in a freshwater fish

Despite many similarities and intuitive links between individual dietary specialization and behavioral inter-individual variation, these phenomena have been studied in isolation, and empirical data confirming relationships between these intraspecific variance sources are lacking. Here we use stable isotope analysis and acoustic telemetry to test the hypothesis that individual specialization in trophic (d15N) and littoral/pelagic prey reliance (d13C) covary with inter-individual variation in movement in a group of 34 free-swimming burbot (Lota lota). By performing stable isotope analysis on tissues with differing isotopic turnover rates (anal fin and dorsal muscle), in 24 lethally sampled burbot, we demonstrate that individual specialization in trophic niche (d15N) and li

Investigate the origins of COVID-19

On 30 December 2019, the Program for Monitoring Emerging Diseases notified the world about a pneumonia of unknown cause in Wuhan, China. Since then, scientists have made remarkable progress in understanding the causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), its transmission, pathogenesis, and mitigation by vaccines, therapeutics, and non-pharmaceutical interventions. Yet more investigation is still needed to determine the origin of the pandemic. Theories of accidental release from a lab and zoonotic spillover both remain viable. Knowing how COVID-19 emerged is critical for informing global strategies to mitigate the risk of future outbreaks

On the Benefits of Transparent Compression for Cost-Effective Cloud Data Storage

International audienceInfrastructure-as-a-Service (IaaS) cloud computing has revolutionized the way we think of acquiring computational resources: it allows users to deploy virtual machines (VMs) at large scale and pay only for the resources that were actually used throughout the runtime of the VMs. This new model raises new challenges in the design and development of IaaS middleware: excessive storage costs associated with both user data and VM images might make the cloud less attractive, especially for users that need to manipulate huge data sets and a large number of VM images. Storage costs result not only from storage space utilization, but also from bandwidth consumption: in typical deployments, a large number of data transfers between the VMs and the persistent storage are performed, all under high performance requirements. This paper evaluates the trade-off resulting from transparently applying data compression to conserve storage space and bandwidth at the cost of slight computational overhead. We aim at reducing the storage space and bandwidth needs with minimal impact on data access performance. Our solution builds on BlobSeer, a distributed data management service specifically designed to sustain a high throughput for concurrent accesses to huge data sequences that are distributed at large scale. Extensive experiments demonstrate that our approach achieves large reductions (at least 40%) of bandwidth and storage space utilization, while still attaining high performance levels that even surpass the original (no compression) performance levels in several data-intensive scenarios

Combustion flame spray of CoNiCrAlY & YSZ coatings

The properties of CoNiCrAlY and ∼7–8%YSZ layers, used as thermal barrier coatings (TBC) to protect hot gas paths of power generation and aerospace gas turbines, that have been deposited through the Combustion Flame Spray (CFS) process, are assessed and compared to coatings of the same materials deposited through Atmospheric Plasma Spray (APS). Fuel-to-oxygen equivalence ratio, combustion and carrier gases flows, torch standoff distance and powder feed rate values have been varied during the CFS tests in order to assess their effect on microstructural characteristics, i.e. thickness, total porosity, oxide level and microhardness. Results show that, in CFS-deposited coatings, although a higher content of oxide strings and porosity is observed compared to APS, also comparable phase transformations and a higher thermal cyclic lifetime can be achieved with an appropriate tuning of the deposition parameters. Thus, the study demonstrates the excellent capability of the CFS process in depositing thermal barrier coating systems, providing a viable alternative deposition technology for this class of materials at significant hardware simplicity. As the CFS setup has a simple design, this research stimulates a miniaturisation concept of the combustion flame spray torch for allowing its deployment into highly restricted workspaces

Monitoring Mycobacterium bovis in Eurasian badgers ( Meles meles ) killed by vehicles in Northern Ireland between 1998 and 2011

Despite extensive long-term eradication programmes, bovine tuberculosis (bTB) remains endemic in much of the British Isles. The cost of the national eradication programme in Northern Ireland was estimated at £23 million in 2010/2011.1 There is evidence that badgers play a role in the maintenance and spread of Mycobacterium bovis to cattle (as reviewed by Allen and others2). Northern Ireland is a small country (13,843 km2) with an agricultural land that is dominated by grass production, which supports 1.6 million cattle among 20,000 farms.3 The estimated badger population of 34,100 (95 per cent confidence interval (CI) 26,200 to 42,000) is widespread and contained within 7600 social groups (95 per cent CI 6200 to 9000).4 A road traffic accident (RTA) survey began in 1998 in Northern Ireland with the aim of describing the occurrence of M bovis within the badger population

Performance Analysis of the SHA-3 Candidates on Exotic Multi-core Architectures

The NIST hash function competition to design a new cryptographic hash standard 'SHA-3' is currently one of the hot topics in cryptologic research, its outcome heavily depends on the public evaluation of the remaining 14 candidates. There have been several cryptanalytic efforts to evaluate the security of these hash functions. Concurrently, invaluable benchmarking efforts have been made to measure the performance of the candidates on multiple architectures. In this paper we contribute to the latter; we evaluate the performance of all second-round SHA-3 candidates on two exotic platforms: the Cell Broadband Engine (Cell) and the NVIDIA Graphics Processing Units (GPUs). Firstly, we give performance estimates for each candidate based on the number of arithmetic instructions, which can be used as a starting point for evaluating the performance of the SHA-3 candidates on various platforms. Secondly, we use these generic estimates and Cell-/GPU-specific optimization techniques to give more precise figures for our target platforms, and finally, we present implementation results of all 10 non-AES based SHA-3 candidates