273,772 research outputs found
The Star Cluster Systems of the Magellanic Clouds
The characteristics of the cluster systems of the Magellanic Clouds, as
inferred from integrated properties, are compared with those from individual
cluster studies and from the field population. The agreement is generally
satisfactory though in the case of the LMC, the lack of clusters older than ~3
Gyr is not reflected in the field population. The possible origin(s) for this
cluster ``age-gap'' are discussed. The SMC cluster age-metallicity relation is
also presented and discussed.Comment: 11 pages, 4 figures. To appear in the Proceedings of IAU Symposium
207, "Extragalactic Star Clusters", eds E. Grebel, D. Geisler and D. Minnit
Public Health Powers in Relation to Tuberculosis in England and France: A Comparison of Approaches
Peer reviewe
Lie algebras with given properties of subalgebras and elements
Results about the following classes of finite-dimensional Lie algebras over a
field of characteristic zero are presented: anisotropic (i.e., Lie algebras for
which each adjoint operator is semisimple), regular (i.e., Lie algebras in
which each nonzero element is regular in the sense of Bourbaki), minimal
nonabelian (i.e., nonabelian Lie algebras all whose proper subalgebras are
abelian), and algebras of depth 2 (i.e., Lie algebras all whose proper
subalgebras are abelian or minimal nonabelian).Comment: 8 pages; v3: added proofs; fixed a list of algebras of depth 2 in
Theorem 7; the statement of Theorem 5 is weakened, the former statement added
as conjecture; to appear in Proceedings of the Conference "Algebra - Geometry
- Mathematical Physics" (Mulhouse, 2011), Springer Proc. Math. Sta
Assessment of maximum inspiratory pressure: Prior submaximal respiratory muscle activity (âwarm-upâ) enhances maximum inspiratory activity and attenuates the learning effect of repeated measurement
The official published version can be obtained from the link belowBackground: The variability of maximal inspiratory pressure (PImax) in response to repeated measurement affects its reliability; published studies have used between three and twenty PImax measurements on a single occasion. Objective: This study investigated the influence of a specific respiratory âwarm-upâ upon the repeated measurement of inspiratory muscle strength and attempts to establish a procedure by which PImax can be assessed with maximum reliability using the smallest number of manoeuvres. Methods: Fourteen healthy subjects, familiar with the Mueller manoeuvre, were studied. The influence of repeated testing on a single occasion was assessed using an 18-measurement protocol. Using a randomised cross-over design, subjects performed the protocol, preceded by a specific respiratory warm-up (RWU) and on another occasion, without any preliminary activity (control). Comparisons were made amongst âbaselineâ (best of the first 3 measurements), âshortâ series (best of 7th to 9th measurement) and âlongâ series (best of the last 3 measurements). Results: Under control conditions, the mean increase (âbaselineâ vs. âlongâ series) was 11.4 (5.8)%; following the RWU, the increase (post RWU âbaselineâ vs. âlongâ series) was 3.2 (10.0)%. There were statistically significant differences between measurements made at all 3 protocol stages (âbaselineâ, âshortâ and âlongâ series) under control conditions, but none following the RWU. Conclusions: The present data suggest that a specific RWU may attenuate the âlearning effectâ during repeated PImax measurements, which is one of the main contributors of the test variability. The use of a RWU may provide a means of obtaining reliable values of PImax following just 3 measurements.This work was partially supported by a grant from the University of Wolverhampton, UK
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