5,008 research outputs found
Strong evidences for a nonextensive behavior of the rotation period in Open Clusters
Time-dependent nonextensivity in a stellar astrophysical scenario combines
nonextensive entropic indices derived from the modified Kawaler's
parametrization, and , obtained from rotational velocity distribution. These
's are related through a heuristic single relation given by , where is the cluster age. In a nonextensive
scenario, these indices are quantities that measure the degree of
nonextensivity present in the system. Recent studies reveal that the index
is correlated to the formation rate of high-energy tails present in the
distribution of rotation velocity. On the other hand, the index is
determined by the stellar rotation-age relationship. This depends on the
magnetic field configuration through the expression , where
and denote the saturation level of the star magnetic field and its
topology, respectively. In the present study, we show that the connection
is also consistent with 548 rotation period data for single
main-sequence stars in 11 Open Clusters aged less than 1 Gyr. The value of
2.5 from our unsaturated model shows that the mean magnetic field
topology of these stars is slightly more complex than a purely radial field.
Our results also suggest that stellar rotational braking behavior affects the
degree of anti-correlation between and cluster age . Finally, we suggest
that stellar magnetic braking can be scaled by the entropic index .Comment: 6 pages and 2 figures, accepted to EPL on October 17, 201
A nonextensive insight to the stellar initial mass function
the present paper, we propose that the stellar initial mass distributions as
known as IMF are best fitted by -Weibulls that emerge within nonextensive
statistical mechanics. As a result, we show that the Salpeter's slope of
2.35 is replaced when a -Weibull distribution is used. Our results
point out that the nonextensive entropic index represents a new approach
for understanding the process of the star-forming and evolution of massive
stars.Comment: 5 pages, 2 figures, Accepted to EP
Overview of context-sensitive technologies for well-being
Today smart devices such as smartphones, smartwatches and activity trackers are widely available and accepted in most developed societies. These devices present a broad set of sensors capable of extracting detailed information about different situations of daily life, which, if used for good, have the potential to improve the quality of life not only for individuals but also for the society in general. One of the key areas where this type of information can help to improve the quality of life is in healthcare since it allows to monitor and infer the current level of well-being of the smart devices carriers. In this paper, some of the available literature about well-being sensing through context-aware data is reviewed. Also, the main types of mechanisms used in these studies are identified. These mechanisms are related to monitoring, generalization, inference, feedback, energy management and privacy. Furthermore, a description of the mechanisms used in each study is presented.info:eu-repo/semantics/acceptedVersio
Perdas de mamão (Carica papaya L.) comercializado no Estado do Rio de Janeiro.
bitstream/item/75828/1/ct40-2000.pd
Frequência de isolados clÃnicos de escherichia coli produtores de β-lactamases de largo espectro
Foi objectivo deste estudo determinar a frequência de
isolados de E. coli produtores de β-lactamases de largo
espectro (ESBLs) tanto em infecções nosocomiais como da
comunidade, e avaliar a susceptibilidade aos antibióticos
entre as estirpes produtoras e não produtoras de ESBLs. Dos
131 isolados investigados apenas 9 (6.8%) se enquadraram
nos critérios definidos pelo CLSI para screening de ESBLs,
e a sua presença foi confirmada por Etest ESBL. Estes
isolados provieram maioritariamente de infecções da
comunidade em doentes com idade avançada e história de
hospitalização prévia. A maioria (66.6%) mostrou resistência
simultânea aos β-lactâmicos estudados, às quinolonas e aos
aminoglicosÃdeos.It was the purpose of this study to determine the frequency
of extendedÂspectrum βÂLactamases (ESBLs) producing
isolates in E. coli, from hospital acquired and community
infections, and to evaluate antibiotic susceptibility between
ESBL producing and nonÂproducing strains. Of 131 isolates
investigated only 9 (6.8%) fulfil CLSI screening criteria for
ESBL, and its production was confirmed by ESBL Etest. This
strains were mainly recovered form community infections in
old aged patients, with an history of previous hospitalisation.
The majority (66.6%) showed simultaneous resistance to the
studied βÂlactams, the quinolones and aminoglycosides
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