19 research outputs found
The chemical evolution of the solar neighbourhood
Recent models of galactic chemical evolution account for updated evolutionary
models of massive stars (with special emphasis on stellar winds) and for the
effects of intermediate mass and massive binaries. The results are summarised.
We also present a critical discussion on possible effects of stellar rotation
on overall galactic chemical evolutionary simulations.Comment: 12 pages, 3 figures, Pacific Rim Conference, Xi'an, China, 11-17 July
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Explosive Nucleosynthesis: What we learned and what we still do not understand
This review touches on historical aspects, going back to the early days of
nuclear astrophysics, initiated by BFH and Cameron, discusses (i) the
required nuclear input from reaction rates and decay properties up to the
nuclear equation of state, continues (ii) with the tools to perform
nucleosynthesis calculations and (iii) early parametrized nucleosynthesis
studies, before (iv) reliable stellar models became available for the late
stages of stellar evolution. It passes then through (v) explosive environments
from core-collapse supernovae to explosive events in binary systems (including
type Ia supernovae and compact binary mergers), and finally (vi) discusses the
role of all these nucleosynthesis production sites in the evolution of
galaxies. The focus is put on the comparison of early ideas and present, very
recent, understanding.Comment: 11 pages, to appear in Springer Proceedings in Physics (Proc. of
Intl. Conf. "Nuclei in the Cosmos XV", LNGS Assergi, Italy, June 2018
Observational Constraints on the Common Envelope Phase
The common envelope phase was first proposed more than forty years ago to
explain the origins of evolved, close binaries like cataclysmic variables. It
is now believed that the phase plays a critical role in the formation of a wide
variety of other phenomena ranging from type Ia supernovae through to binary
black holes, while common envelope mergers are likely responsible for a range
of enigmatic transients and supernova imposters. Yet, despite its clear
importance, the common envelope phase is still rather poorly understood. Here,
we outline some of the basic principles involved, the remaining questions as
well as some of the recent observational hints from common envelope phenomena -
namely planetary nebulae and luminous red novae - which may lead to answering
these open questions.Comment: 29 pages, 8 figures. To appear in the book "Reviews in Frontiers of
Modern Astrophysics: From Space Debris to Cosmology" (eds. Kabath, Jones and
Skarka; publisher Springer Nature) funded by the European Union Erasmus+
Strategic Partnership grant "Per Aspera Ad Astra Simul"
2017-1-CZ01-KA203-03556
The Nordic maintenance care program â case management of chiropractic patients with low back pain: A survey of Swedish chiropractors
<p>Abstract</p> <p>Background</p> <p>Chiropractic treatment for low back pain (LBP) can often be divided into two phases: Initial treatment of the problem to attempt to remove pain and bring it back into its pre-clinical or maximum improvement status, and "maintenance care", during which it is attempted to maintain this status. Although the use of chiropractic maintenance care has been described and discussed in the literature, there is no information as to its precise indications. The objective of this study is to investigate if there is agreement among Swedish chiropractors on the overall patient management for various types of LBP-scenarios, with a special emphasis on maintenance care.</p> <p>Method</p> <p>The design was a mailed questionnaire survey. Members of the Swedish Chiropractors' Association, who were participants in previous practice-based research, were sent a closed-end questionnaire consisting of nine case scenarios and six clinical management alternatives and the possibility to create one's own alternative, resulting in a "nine-by-seven" table. The research team defined its own pre hoc choice of "clinically logical" answers based on the team's clinical experience. The frequency of findings was compared to the suggestions of the research team.</p> <p>Results</p> <p>Replies were received from 59 (60%) of the 99 persons who were invited to take part in the study. A pattern of self-reported clinical management strategies emerged, largely corresponding to the "clinically logical" answers suggested by the research team. In general, patients of concern would be referred out for a second opinion, cases with early recovery and without a history of previous low back pain would be quickly closed, and cases with quick recovery and a history of recurring events would be considered for maintenance care. However, also other management patterns were noted, in particular in the direction of maintenance care.</p> <p>Conclusion</p> <p>To a reasonable extent, Swedish chiropractors participating in this survey appear to agree on the clinical management for different cases of LBP.</p