895 research outputs found
Neutral pion decay in dense skyrmion matter
We study the density dependence of the decay using
the Skyrme Lagrangian to describe simultaneously both the matter background and
mesonic fluctuations. Pion properties such as mass and decay constant are
modified by the medium. This leads to large suppression at high density of both
photo-production from the neutral pion and the reverse process. The in-medium
effective charge of are also discussed in the same framework.Comment: 8 pages, 4 figures. Corrections in light of referee comment
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Ambient noise tomography reveals basalt and sub-basalt velocity structure beneath the Faroe Islands, North Atlantic
© 2017 Elsevier B.V. Ambient noise tomography is applied to seismic data recorded by a portable array of seismographs deployed throughout the Faroe Islands in an effort to illuminate basalt sequences of the North Atlantic Igneous Province, as well as underlying sedimentary layers and Precambrian basement. Rayleigh wave empirical Green's functions between all station pairs are extracted from the data via cross-correlation of long-term recordings, with phase weighted stacking implemented to boost signal-to-noise ratio. Dispersion analysis is applied to extract inter-station group travel-times in the period range 0.5–15 s, followed by inversion for period-dependent group velocity maps. Subsequent inversion for 3-D shear wave velocity reveals the presence of significant lateral heterogeneity (up to 25%) in the crust. Main features of the final model include: (i) a near-surface low velocity layer, interpreted to be the Malinstindur Formation, which comprises subaerial compound lava flows with a weathered upper surface; (ii) a sharp velocity increase at the base of the Malinstindur Formation, which may mark a transition to the underlying Beinisvørð Formation, a thick laterally extensive layer of subaerial basalt sheet lobes; (iii) a low velocity layer at 2.5–7.0 km depth beneath the Beinisvørð Formation, which is consistent with hyaloclastites of the Lopra Formation; (iv) an upper basement layer between depths of 5–9 km and characterized by S wave velocities of approximately 3.2 km/s, consistent with low-grade metamorphosed sedimentary rocks; (v) a high velocity basement, with S wave velocities in excess of 3.6 km/s. This likely reflects the presence of a crystalline mid-lower crust of Archaean continental origin. Compared to previous interpretations of the geological structure beneath the Faroe Islands, our new results point to a more structurally complex and laterally heterogeneous crust, and provide constraints which may help to understand how continental fragments are rifted from the margins of newly forming ocean basins
Women and special vulnerability: Commentary "On the principle of respect for human vulnerability and personal integrity," UNESCO, International Bioethics Committee report
Healthcare stakeholders' perspective on barriers to integrated care in Switzerland: Results from the open-ended question of a nationwide survey.
We aimed to identify the main barriers to integrated care (IC) as reported by healthcare stakeholders from various linguistic regions and health system specificities, according to their reality of practice.
Information was gathered through an open-ended question from a national survey conducted in Switzerland in 2019. Responses were analysed qualitatively with the IRaMuTeQ software.
Answers from 410 respondents were obtained. Respondents reported barriers at two levels: the system and professional level. Threat to financial benefits, concerns for patient data sharing and tensions between quality of care and benefits for patients versus costs were mentioned at the professional level, in their activity and in patient care. At the system level, limitations at the political level due to federalism and the lack of support and training for professionals were important barriers, in addition to the lack of recognition and compensation for professionals and the fragmented functioning of the health care system.
Our study underlines the importance of implementing innovative funding strategies and reimbursement schemes, as well as political willingness to move towards IC. The alignment between federal policies and cantonal specificities also appears as necessary to achieve involvement of professionals, promote integration of services and coordination of professionals for continuous and efficient care
College Student Home Computer Security Adoption
The home Internet user faces a hostile environment abundant in potential attacks on their computers. These attacks have been increasing at an alarming rate and cause damage to individuals and organizations regularly, and have the potential to cripple the critical infrastructures of entire countries. Recent research has determined that some individuals are not utilizing additional software protections available to mitigate these potential security risks. This paper seeks to clarify the reasons by proposing a conceptual framework that utilizes the Health Belief Model as a possible way to explain why some people do not perceive a threat sufficient to prompt the adoption of computer security software
Infrequent transmission of double-stranded-rna virus-particles but absence of DNA proviruses in single ascospore cultures of gaeumannomyces-graminis
A common deep source for upper-mantle upwellings below the Ibero-western Maghreb region from teleseismic P-wave travel-time tomography
Upper-mantle upwellings are often invoked as the cause of Cenozoic volcanism in the Ibero-western Maghreb region. However, their nature, geometry and origin are unclear. This study takes advantage of dense seismic networks, which cover an area extending from the Pyrenees in the north to the Canaries in the south, to provide a new high-resolution P-wave velocity model of the upper-mantle and topmost lower-mantle structure. Our images show three subvertical upper-mantle upwellings below the Canaries, the Atlas Ranges and the Gibraltar Arc, which appear to be rooted beneath the upper-mantle transition zone (MTZ). Two other mantle upwellings beneath the eastern Rif and eastern Betics surround the Gibraltar subduction zone. We propose a new geodynamic model in which narrow upper-mantle upwellings below the Canaries, the Atlas Ranges and the Gibraltar Arc rise from a laterally-propagating layer of material below the MTZ, which in turn is fed by a common deep source below the Canaries. In the Gibraltar region, the deeply rooted upwelling interacts with the Gibraltar slab. Quasi-toroidal flow driven by slab rollback induces the hot mantle material to flow around the slab, creating the two low-velocity anomalies below the eastern Betics and eastern Rif. Our results suggest that the Central Atlantic plume is a likely source of hot mantle material for upper-mantle upwellings in the Ibero-western Maghreb region
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