High-temperature ceramics for automobile gas turbines

The employment of the high operational temperatures makes it necessary to use, for the construction of the turbines, ceramic materials such as silicon nitride or silicon carbide. Investigations concerning the development of turbine components made of such materials are conducted by a German automobile manufacturer and the ceramics industry. The current status of these investigations is reviewed. Flame tubes and guide-vane rings have successfully passed tests lasting 20 hours. Prototype turbine wheels have withstood the effects of peripheral speeds of 450 m/s. They also showed resistance to thermal shocks which were as high as 6-0 K/s

High temperature ceramics for automobile gas turbines. Part 2: Development of ceramic components

The development of ceramic components for automobile gas turbine engines is described with attention given to the steady and unsteady thermal conditions the ceramics will experience, and their anti-corrosion and strain-resistant properties. The ceramics considered for use in the automobile turbines include hot-pressed Si3N4, reaction-sintered, isostatically pressed Si3N4, hot-pressed SiC, reaction-bonded SiC, and glass ceramics. Attention is given to the stress analysis of ceramic structures and the state of the art of ceramic structural technology is reviewed, emphasizing the use of ceramics for combustion chambers and ceramic shrouded turbomachinery (a fully ceramic impeller)

Lightweight Acquisition and Ranging of Flows in the Data Plane

As networks get more complex, the ability to track almost all the flows is becoming of paramount importance. This is because we can then detect transient events impacting only a subset of the traffic. Solutions for flow monitoring exist, but it is getting very difficult to produce accurate estimations for every tuple given the memory constraints of commodity programmable switches. Indeed, as networks grow in size, more flows have to be tracked, increasing the number of tuples to be recorded. At the same time, end-host virtualization requires more specific flowIDs, enlarging the memory cost for every single entry. Finally, the available memory resources have to be shared with other important functions as well (e.g., load balancing, forwarding, ACL). To address those issues, we present FlowLiDAR (Flow Lightweight Detection and Ranging), a new solution that is capable of tracking almost all the flows in the network while requiring only a modest amount of data plane memory which is not dependent on the size of flowIDs. We implemented the scheme in P4, tested it using real traffic from ISPs and compared it against four state-of-the-art solutions: FlowRadar, NZE, PR-sketch, and Elastic Sketch. While those can only reconstruct up to 60% of the tuples, FlowLiDAR can track 98.7% of them with the same amount of memory

Global citizenship as the completion of cosmopolitanism

A conception of global citizenship should not be viewed as separate from, or synonymous with, the cosmopolitan moral orientation, but as a primary component of it. Global citizenship is fundamentally concerned with individual moral requirements in the global frame. Such requirements, framed here as belonging to the category of individual cosmopolitanism, offer guidelines on right action in the context of global human community. They are complementary to the principles of moral cosmopolitanism – those to be used in assessing the justice of global institutions and practices – that have been emphasised by cosmopolitan political theorists. Considering principles of individual and moral cosmopolitanism together can help to provide greater clarity concerning individual duties in the absence of fully global institutions, as well as clarity on individual obligations of justice in relation to emerging and still-developing trans-state institutions

Los medios de comunicación y el tatuaje contemporáneo

El fenómeno del tatuaje, inicialmente asociado a grupos étnicos tradicionales y más tarde a culturas marginales,ha tenido en las últimas décadas una expresión inédita en las sociedades contemporáneas extendiéndose entre sectores poblacionales muy diversos, antaño ajenos a esta práctica. Originariamente asociado a lo ritual y lo sagrado, ha devenido para algunos en elemento de moda impulsado por los canales de difusión mediada. Su presencia es evidente en las calles pero también en los medios de comunicación. En este artículo se aborda el papel de los medios de comunicación en este estado de cosas. En esta investigación se han realizado entrevistas en profundidad tanto a profesionales del tatuaje como a personas tatuadas para conocer los diversos aspectos implicados en la mediatización del tatuaje y en su ejecución. Como resultado de las entrevistas se ha podido constatar que los medios han incidido en la extensión de esta práctica, tanto desde la perspectiva evidente de su presencia cuantitativa en entornos urbanos cuanto desde los diferentes modos en los que la visibilidad que los media otorgan al tatuaje a través de diversas plataformas y formatos interviene en múltiples ámbitos que abarcan desde la formación de los tatuadores, los estilos visuales, la legitimación social de su uso, el significado personal que se da a los tatuajes y la modulación del relato en torno al hecho de tatuarse, entre otros

The Relationship between Pneumocystis infection in animal and human Hosts, and climatological and environmental air pollution factors: a systematic review

BACKGROUND: Over the past decade, there has been rising interest in the interaction of Pneumocystis with the environment. This interest has arisen in part from the demonstration that environmental factors have important effects on the viability and transmission of microbes, including Pneumocystis. Environmental factors include climatological factors such as temperature, humidity, and precipitation, and air pollution factors including carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter. METHODS: We undertook a systematic review in order to identify environmental factors associated with Pneumocystis infection or PCP, and their effects on human and animal hosts. RESULTS: The systematic review found evidence of associations between Pneumocystis infection in animal and human hosts, and climatological and air pollution factors. Data from human studies infers that rather than a seasonal association, presentation with PCP appears to be highest when the average temperature is between 10 and 20°C. There was evidence of an association with hospitalization with PCP and ambient air pollution factors, as well as evidence of an effect of air pollution on both systemic and bronchoscopic lavage fluid humoral responses to Pneumocystis. Interpretation of human studies was confounded by possible genetically-determined predisposition to, or protection from infection. CONCLUSIONS: This systematic review provides evidence of associations between Pneumocystis infection in both animal and human hosts, and climatological and environmental air pollution factors. This information may lead to an improved understanding of the conditions involved in transmission of Pneumocystis in both animal and human hosts. Such knowledge is critical to efforts aimed at prevention

Index insurance and climate risk management: addressing social equity

Motivation Fair distribution of benefits from index insurance matters. Lack of attention to social equity can reinforce inequalities and undermine the potential index insurance holds as a tool for climate risk management that is also pro-poor. Purpose The aims are to: (i) examine social equity concerns raised by index insurance in the context of climate risk management; (ii) consider how greater attention can be given to social equity in index insurance initiatives; and (iii) reflect on the policy challenges raised by seeking to take social equity into account as a mechanism for climate risk reduction. Approach and methods The article draws on learning from the CGIAR’s Research Program on Climate Change, Agriculture and Food Security (CCAFS) and presents the cases of the Index Based Livelihoods Insurance (IBLI) and Agriculture and Climate Risk Enterprise Ltd. (ACRE) in East Africa. It proposes a framework for unpacking social equity related to equitable access, procedures, representation and distribution within index insurance schemes Findings Systematically addressing social equity raises hard policy choices for index insurance initiatives without straightforward solutions. Attention to how benefits and burdens of index insurance are distributed raises the unpalateable truth for development policy that the poorest members of rural society can be excluded. Nevertheless, a focus on social equity may open up opportunities to ensure index insurance is linked to more socially just climate risk management. At the very least, it may prevent index insurance from generating greater inequality. Taking social equity into account thus, shifts the focus from agricultural systems in transition per se to systems with potential to incorporate societal transformation through distributive justice. Policy implications A framework is presented for unpacking different dimensions of social equity in index insurance schemes. It is intended to facilitate identification of opportunities for building outcomes that are more equitable, with greater potential for inclusion and fairer distribution

Urban brown rats (Rattus norvegicus) as possible source of multidrug-resistant Enterobacteriaceae and meticillin-resistant Staphylococcus spp., Vienna, Austria, 2016 and 2017

Background: Brown rats (Rattus norvegicus) are an important wildlife species in cities, where they live in close proximity to humans. However, few studies have investigated their role as reservoir of antimicrobial-resistant bacteria. Aim: We intended to determine whether urban rats at two highly frequented sites in Vienna, Austria, carry extended-spectrum β-lactamase-producing Enterobacteriaceae, fluoroquinolone-resistant Enterobacteriaceae and meticillin-resistant (MR) Staphylococcus spp. (MRS). Methods: We surveyed the presence of antimicrobial resistance in 62 urban brown rats captured in 2016 and 2017 in Vienna, Austria. Intestinal and nasopharyngeal samples were cultured on selective media. We character-ised the isolates and their antimicrobial properties using microbiological and genetic methods including disk diffusion, microarray analysis, sequencing, and detection and characterisation of plasmids. Results: Eight multidrug-resistant Escherichia coli and two extensively drug-resistant New Delhi metallo-β-lactamases-1 (NDM-1)-producing Enterobacter xiangfangensis ST114 (En. cloacae complex) were isolated from nine of 62 rats. Nine Enterobacteriaceae isolates harboured the blaCTX-M gene and one carried a plasmid-encoded ampC gene (blaCMY-2). Forty-four MRS were isolated from 37 rats; they belonged to seven different staphylococcal species: S. fleuret-tii, S. sciuri, S. aureus, S. pseudintermedius, S. epidermidis, S. haemolyticus (all mecA-positive) and mecC-positive S. xylosus. Conclusion: Our findings suggest that brown rats in cities are a potential source of multidrug-resistant bacteria, including carbapenem-resistant En. xiangfangensis ST114. Considering the increasing worldwide urbanisation, rodent control remains an important priority for health in modern cities. © 2019, European Centre for Disease Prevention and Control (ECDC). All rights reserved

Local management and landscape composition affect predatory mites in European wine-growing regions

Sustainable land use in agricultural landscapes is essential to counteract the global decline of biodiversity, as well to ensure ecosystem services like natural pest control. Phytoseiid mites are key natural enemies of pest mites in vineyards but how local management and landscape context affect phytoseiid mites remains poorly known. In this study, we examined the effects of farming systems, inter-row management and landscape composition on phytoseiid mite communities in 156 vineyards across five European wine-growing regions. Our results showed that phytoseiid communities were mainly dominated by one or two phytoseiid species across Europe and that local management was a major factor affecting population densities. According to the wine-growing regions, phytoseiid mite densities benefited from integrated pest management or conventional farming compared to organic farming and from spontaneous vegetation cover compared to seeded cover crops. Moreover, mite densities benefited from increasing proportions of vineyards at the landscape scale. The farming systems effects were most likely related to the positive impact of the lower pesticide use in integrated and conventional vineyards. The positive effect of spontaneous vegetation cover could be related to a better supply of nutritive pollen as food resource compared to seeded cover crops, which depends on the plant species in the inter-row. Our findings indicated accordingly that a reduced pesticide use, and inter-row management are crucial factors for promoting pest control by predatory mites in European vineyards. Moreover, the proportion of viticultural area in the landscape is a considerable factor to retain stable phytoseiid mite populations.This research was funded by the research project SECBIVIT, which was funded through the 2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND program, with the funding organizations: Agencia Estatal de Investigación (Ministerio de ciencia e innovación/ES/Grant #10.13039/501100011033), Austrian Science Fund (AT/Grant #I 4025-B32), Federal Ministry of Education and Research and Projektträger VDI/VDE Innovation + Technik GmbH (DE), French National Research Agency (FR), Netherlands Organisation for Scientific Research (NL), National Science Foundation (US/Grant #1850943) and Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (RO)