A Comparison of Radio and X-Ray Morphologies of Four Clusters of Galaxies Containing Radio Halos

Clusters of galaxies may contain cluster-wide, centrally located, diffuse radio sources, called halos. They have been found to show morphologies similar to those of the X-ray emission. To quantify this qualitative statement we performed a point-to-point comparison of the radio and the X-ray emission for four clusters of galaxies containing radio halos: Coma, Abell 2255, Abell 2319, Abell 2744. Our study leads to a linear relation between the radio and the X-ray surface brightness in two clusters, namely Abell 2255 and Abell 2744. In Coma and A2319 the radio and the X-ray brightnesses seem to be related with a sub-linear power law. Implications of these findings within simple radio halo formation models are briefly discussed.Comment: 9 pages, 13 .ps figures, accepted by A&

Evolution of porosity in carbide-derived carbon aerogels

Carbide-derived carbon (CDC) aerogel monoliths with very high porosity are synthesized starting from polymeric precursors. Cross-linking by platinum-catalyzed hydrosilylation of polycarbosilanes followed by supercritical drying yields preceramic aerogels. After ceramic conversion and silicon extraction in hot chlorine gas, hierarchically porous carbon materials with specific surface areas as high as 2122 m² g⁻¹ and outstanding total pore volumes close to 9 cm³ g⁻¹ are obtained. Their pore structure is controllable by the applied synthesis temperature as shown by combined nitrogen (-196 °C) and carbon dioxide (0 °C) measurements coupled with electron microscopic methods. The combination of large micropore volumes and the aerogel-type pore system leads to advanced adsorption properties due to a combination of large storage capacities and effective materials transport in comparison with purely microporous reference materials as shown by thermal response measurements

Exclusion and reappropriation: Experiences of contemporary enclosure among children in three East Anglian schools

Transformations of the landscapes which children inhabit have significant impacts on their lives; yet, due to the limited economic visibility of children’s relationships with place, they have little stake in those transformations. Their experience, therefore, illustrates in an acute way the experience of contemporary enclosure as a mode of subordination. Following fieldwork in three primary schools in South Cambridgeshire, UK, we offer an ethnographic account of children’s experiences of socio-spatial exclusion. Yet, we suggest that such exclusion is by no means an end-point in children’s relationships with place. Challenging assumptions that children are disconnected from nature, we argue that through play and imaginative exploration of their environments, children find ways to rebuild relationships with places from which they find themselves excluded. This is the author accepted manuscript. The final version is available from SAGE via http://dx.doi.org/10.1177/026377581664194

Nanomechanics of individual aerographite tetrapods

R.A., O.L. and K.S. would like to thank the German Research Foundation (DFG) for the financial support under schemes AD 183/17-1 and SFB 986-TP-B1, respectively, and the Graphene FET Flagship. R.M. and D.E. would like to thank for financial support from Latvian Council of Science, no. 549/2012. N.M.P. is supported by the European Research Council (ERC PoC 2015 SILKENE no. 693670) and by the European Commission H2020 under the Graphene Flagship (WP14 ‘Polymer Composites’, no. 696656) and under the FET Proactive (‘Neurofibres’ no. 732344). S.S. acknowledges support from SILKENE

Degradation of haloaromatic compounds

An ever increasing number of halogenated organic compounds has been produced by industry in the last few decades. These compounds are employed as biocides, for synthetic polymers, as solvents, and as synthetic intermediates. Production figures are often incomplete, and total production has frequently to be extrapolated from estimates for individual countries. Compounds of this type as a rule are highly persistent against biodegradation and belong, as "recalcitrant" chemicals, to the class of so-called xenobiotics. This term is used to characterise chemical substances which have no or limited structural analogy to natural compounds for which degradation pathways have evolved over billions of years. Xenobiotics frequently have some common features. e.g. high octanol/water partitioning coefficients and low water solubility which makes for a high accumulation ratio in the biosphere (bioaccumulation potential). Recalcitrant compounds therefore are found accumulated in mammals, especially in fat tissue, animal milk supplies and also in human milk. Highly sophisticated analytical techniques have been developed for the detection of organochlorines at the trace and ultratrace level

Perfect bodies: The relation of gay men’s body image to their appearance enhancement product consumption behaviors

Purpose: The purpose of this paper is to investigate how dimensions of body image relate to product involvement among gay men. Design/methodology/approach: A survey consisting of body image and product involvement measures was administered to 147 self-identified gay men. Multiple regression was used to examine the relations of the significant body image variables to each of the consumer behavior outcomes in separate analyses. Findings: The more the men were behaviorally invested in their appearance predicted a higher frequency of shopping each month for apparel and grooming-related products. The stronger the men’s psychological drive to have a lean body and the more they focused on their appearance and invested in their looks, the more likely they were to view apparel as important to them. The more psychologically and behaviorally involved the gay men reported being with their appearance, the more importance they gave to grooming-related products. Research limitations/implications: The sample was drawn primarily from a college population, limiting findings to this age cohort. Practical implications: The findings of the current research demonstrate the importance of appearance management products to the gay market, where commodities are often used to enhance or maintain a perceived self-image. Retailers can use this information to establish appropriate service options and effective marketing initiatives. Originality/value: This study replicated others that have investigated gay men’s involvement in consumer products. However, the current study looked at the relationship between involvement and body image

Working from the inside out: Fostering intrinsic motivation and expanding our criteria for conservation success

Primatological research is often associated with understanding animals and their habitats, yet practical conservation depends entirely on human actions. This encompasses the activities of Indigenous and local people, conservationists, and NGOs working on the ground, as well as more remote funders and policymakers. In this paper we explore what it means to be a conservationist in the 2020s. While many primatologists accept the benefits of more socially inclusive dimensions of research and conservation practice, in reality there remain many challenges. We discuss the role primatologists can play to enhance interdisciplinary working and their relationships with communities living in and around their study sites, and examine how increased reflexivity and consideration of one’s positionality can improve primatological practice. Emphasis on education and stakeholder consultation may still echo colonial, top-down dialogues, and the need for greater emphasis on genuine knowledge-sharing among all stakeholders should be recognised. If we are sincere about this approach, we might need to redefine how we see, consider, and define conservation success. We may also have to embrace more compromises. By evaluating success in conservation we explore how reflexive engagements with our positionality and equitable knowledge-sharing contribute to fostering intrinsic motivation and building resilience

The role of tumor vascularisation in benign and malignant cardiovascular neoplasms: a comparison of cardiac myxoma and sarcomas of the pulmonary artery

Neoangiogenesis is involved in the development and progression of malignant tumors. Vascular endothelial growth factor (VEGF) and its receptors have been designated a central part in this process. Since the significance of the assessment of angiogenesis in soft tissue tumors is still a matter of debate, we investigated the vascularisation of cardiac myxomas and compared it with pulmonary artery sarcomas (PAS). Angiogenesis in 18 PAS and 20 myxomas was assessed by morphometry. An immunohistochemical analysis of growth factors and their receptors, HIF-1alpha and tumor-associated macrophages (TAM) was performed. Results showed that microvessel density (MVD) in PAS was significantly higher at the border of necrosis versus the areas without necrosis but no difference was observed between PAS and myxomas. Vascular surface area (VSA) and intervascular distances showed a higher vascularisation at the border of necrosis compared to myxomas, which was not significant. VEGF expression was higher in PAS compared to myxomas and was prominent at the sites of necrosis. HIF-1alpha expression was marked at the border of necrosis in PAS but was absent in myxomas. Infiltration of the macrophages was significantly higher in myxomas compared to the sarcomas. VEGFR-2 expression was detected in a subset of tumor cells and in blood vessels mainly at the tumor periphery, whereas VEGFR-1 was weakly expressed in the tumors but prominent in the macrophages in cardiac myxomas. PDGF receptors and their ligands are strongly present in myxomas and to a lesser extent in the sarcomas. In conclusion, benign and malignant cardiovascular tumors with a different pathophysiology develop a comparable vascularisation. Hypoxia appears to be the strongest inducer of neoangiogenesis in the sarcomas. The expression of receptor tyrosine kinases of the VEGF family provides a basis for an adjuvant therapy

Particle Entrapment in Rolling Element Bearings: The Effect of Ellipticity, Nature of Materials, and Sliding

International audienceThis study on particle entrapment within elastohydrodynamic contacts reports experimental tests mimicking rolling element bearings contacts using a twin-disc machine with a contaminated lubricant as well as numerical simulations. The ball bearing contacts might be non-ideally circular, be composed of a hybrid couple of contact materials and be operated under rolling–sliding conditions. This study focused on the relative importance of each of these configurations to the mechanisms responsible for particle entrapment. It was found experimentally and confirmed numerically that the contact ellipticity is of primary importance to entrapment probability. Tests mixing two-by-two pure rolling and non-zero SRR, different materials and contact configurations revealed combined mechanisms leading to entrapment and surface damage