Search Results (6)

The solar terminator is a moving boundary between day-side and night-side regions on the Earth, which is a substantial source of perturbations in the ionosphere. In the vicinity of the solar terminator, essential parameters like ${\mathrm{S}}_4$ index measurements are widely analyzed in order to monitor and predict perturbations in the ionosphere. The utilization of the scintillation index ${\mathrm{S}}_4$ is a well-accepted approach to describe the amplitude/intensity fluctuation of a received signal, predominantly caused by small-scale irregularities of the ionospheric plasma. We report on the longitudinal daily and seasonal occurrence of GNSS signal scintillations, using the data derived from the GNSS stations in Bahir Dar, Ethiopia, Lomé, Togo and Dakar, Senegal. The observed seasonal climatology of GNSS signal scintillations in equatorial Africa is adequately explained by the alignment of the solar terminator and local geomagnetic declination line. It should be pointed out that the strongest scintillations are most frequently observed during the time when the solar terminator is best aligned with the geomagnetic declination line. At all three stations, the comparison of computational and observational results indicated that the scintillation activity culminated around equinoxes in the years 2014, 2015 and 2016. Comparatively, the western equatorial Africa sector has the most intense, longest-lasting, and highest scintillation occurrence rate in equinoctial seasons in all three years. For the first time, we show that the seasonal variation of the scintillation peaks changes systematically from west to east at equatorial GNSS stations over Africa. A detailed analysis of the solar day–night terminator azimuth at ionospheric heights including the time equation shows that the scintillation intensity has a maximum if the azimuth of the terminator coincides with the declination line of the geomagnetic field. Due to the remarkable change of the declination by about 10° at the considered GNSS stations, the distance between scintillation peaks increases by 46 days when moving westward from the Bahir Dar to the Dakar GNSS station. The observations agree quite well with the computational results, thus confirming Tsunoda’s theory. Full article

In this review, we describe different families of metastable materials, some of them with relevant technological applications, which can be stabilized at moderate pressures 2–3.5 GPa in a piston-cylinder press. The synthesis of some of these systems had been previously reported under higher hydrostatic pressures (6–10 GPa), but can be accessed under milder conditions in combination with reactive precursors prepared by soft-chemistry techniques. These systems include perovskites with transition metals in unusual oxidation states (e.g., RNiO₃ with Ni³⁺, R = rare earths); double perovskites such as RCu₃Mn₄O₁₂ with Jahn–Teller Cu²⁺ ions at A sites, pyrochlores derived from Tl₂Mn₂O₇ with colossal magnetoresistance, pnictide skutterudites M_xCo₄Sb₁₂ (M = La, Yb, Ce, Sr, K) with thermoelectric properties, or metal hydrides Mg₂MH_x (M = Fe, Co, Ni) and AMgH₃ (A: alkali metals) with applications in hydrogen storage. The availability of substantial amounts of sample (0.5–1.5 g) allows a complete characterization of the properties of interest, including magnetic, transport, thermoelectric properties and so on, and the structural characterization by neutron or synchrotron X-ray diffraction techniques. Full article

This article presents data from our investigations in Kristiansand, the largest city in Southern Norway, an area sometimes called Norway’s ‘Bible belt’. We investigate how social media is reshaping social relations in the city, looking especially at how social order is generated, reinforced, and challenged on social media platforms. Drawing on the figurational sociology of Norbert Elias, as well as findings from research conducted among Muslim immigrants in Scandinavian cities and their response to what they perceive as the dominant media frame, we focus this article on a less visible group of outsiders in the local social figuration: young ex- and non-religious persons. The mediated and enacted performances of this loosely defined group and their interactions with more influential others provide a case study in how non-religious identities and networked communities are construed not (only) based on explicit rejection of religion but also in negotiation with a social order that happens to carry locally specific ‘religious’ overtones. With respect to the mediatization of religion we extend empirical investigation of the theory to social media, arguing that what while religious content is shaped by social media forms, in cases where religious identifiers already convey prestige in local social networks, social media may increase the influence of these networks, thus deepening processes of social inclusion for those in dominant groups and the exclusion of outsiders. In this way, platforms which are in principle open and in practice provide space for minorities to self-organise, also routinely reinforce existing power relations. Full article

Community-based participatory research is a growing approach, but often includes higher levels of community engagement in the research design and data collection stages than in the data interpretation stage. Involving study participants in this stage could further knowledge justice, science that aligns with and supports social justice agendas. This article reports on two community-based participatory environmental health surveys conducted between 2015 and 2019 in an industrial region near Marseille, France, and focuses specifically on our approach of organizing focus groups to directly involve residents and community stakeholders in the analysis and interpretation process. We found that, in these focus groups, residents triangulated across many different sources of information—study findings, local knowledge, and different types of expert knowledge—to reach conclusions about the health of their community and make recommendations for what should be done to improve community health outcomes. We conclude that involving residents in the data analysis and interpretation stage can promote epistemic justice and lead to final reports that are more useful to community stakeholders and decision-makers. Full article

Ecological economics has relied too much on priorities and institutional conventions defined by the high energy/throughput era of social democracy. Future research should focus on the political economy of a survival unit (Elias) based upon Livelihood as counterbalance to both State and Market. Drawing on the work of Polanyi, Elias, Gellner and Ong, capitalist modernization is analyzed in terms of the emergence of a society of individuals and the replacement of the survival units of place-bound bound family and community by one in which the State acts in concert with the Market. The operation of welfare systems is shown to depend upon ongoing economic growth and a continual flow of fiscal resources. The politics of this survival unit depends upon high levels of mutual identification and an affective-cognitive ‘we imaginary’. Increasing diversity, a political rejection of nationalism as a basis for politics and limits to economic growth, are likely to present an existential threat to the State–Market survival unit. A reversal of globalization, reconsolidation of the nation-state, a reduction in the scope of national and global markets and the expansion of informal processes of manufacture and distribution may provide a plausible basis for a hybrid Livelihood–Market–State survival unit. The politics of such a reorientation would straddle the existing left–right divide in disruptive and unsettling ways. Examples are given of pre-figurative forms of reciprocation and association that may be indicative of future arrangements. Full article

We discuss how the normative dimension of sustainability can be captured in terms of justice. We (i) identify the core characteristics of the concept of sustainability and discuss underlying ethical, ontological and epistemological assumptions; (ii) introduce a general conceptual structure of justice for the analysis and comparison of different conceptions of justice; and (iii) employ this conceptual structure to determine the specific characteristics and challenges of justice in the context of sustainability. We demonstrate that sustainability raises specific and partly new challenges of justice regarding the community of justice, the judicandum, the informational base, the principles, and the instruments of justice. Full article