214 research outputs found
Aluminium salalen complexes based on 1,2-diaminocyclohexane and their exploitation for the polymerisation of <em>rac</em>-lactide
BioCIDER: a Contextualisation InDEx for biological Resources discovery
Summary
The vast, uncoordinated proliferation of bioinformatics resources (databases, software tools, training materials etc.) makes it difficult for users to find them. To facilitate their discovery, various services are being developed to collect such resources into registries. We have developed BioCIDER, which, rather like online shopping ‘recommendations’, provides a contextualization index to help identify biological resources relevant to the content of the sites in which it is embedded
Rapid-response radio observations of short GRB 181123B with the Australia Telescope Compact Array
We introduce the Australia Telescope Compact Array (ATCA) rapid-response mode
by presenting the first successful trigger on the short-duration gamma-ray
burst (GRB) 181123B. Early-time radio observations of short GRBs may provide
vital insights into the radio afterglow properties of Advanced LIGO- and
Virgo-detected gravitational wave events, which will in turn inform follow-up
strategies to search for counterparts within their large positional
uncertainties. The ATCA was on target within 12.6 hr post-burst, when the
source had risen above the horizon. While no radio afterglow was detected
during the 8.3 hr observation, we obtained force-fitted flux densities of and Jy at 5.5 and 9 GHz, respectively. Afterglow
modelling of GRB 181123B showed that the addition of the ATCA force-fitted
radio flux densities to the Swift X-ray Telescope detections provided more
stringent constraints on the fraction of thermal energy in the electrons
(log rather than log derived without the inclusion of the ATCA values), which
is consistent with the range of typical derived from GRB afterglow
modelling. This allowed us to predict that the forward shock may have peaked in
the radio band days post-burst, producing detectable radio emission
days post-burst. Overall, we demonstrate the potential for
extremely rapid radio follow-up of transients and the importance of triggered
radio observations for constraining GRB blast wave properties, regardless of
whether there is a detection, via the inclusion of force-fitted radio flux
densities in afterglow modelling efforts.Comment: 15 pages, 7 figures, accepted for publication in MNRA
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Synthesis of accelerograms compatible with the Chinese GB 50011-2001 design spectrum via harmonic wavelets: artificial and historic records
A versatile approach is employed to generate artificial accelerograms which satisfy the compatibility criteria prescribed by the Chinese aseismic code provisions GB 50011-2001. In particular, a frequency dependent peak factor derived by means of appropriate Monte Carlo analyses is introduced to relate the GB 50011-2001 design spectrum to a parametrically defined evolutionary power spectrum (EPS). Special attention is given to the definition of the frequency content of the EPS in order to accommodate the mathematical form of the aforementioned design spectrum. Further, a one-to-one relationship is established between the parameter controlling the time-varying intensity of the EPS and the effective strong ground motion duration. Subsequently, an efficient auto-regressive moving-average (ARMA) filtering technique is utilized to generate ensembles of non-stationary artificial accelerograms whose average response spectrum is in a close agreement with the considered design spectrum. Furthermore, a harmonic wavelet based iterative scheme is adopted to modify these artificial signals so that a close matching of the signals’ response spectra with the GB 50011-2001 design spectrum is achieved on an individual basis. This is also done for field recorded accelerograms pertaining to the May, 2008 Wenchuan seismic event. In the process, zero-phase high-pass filtering is performed to accomplish proper baseline correction of the acquired spectrum compatible artificial and field accelerograms. Numerical results are given in a tabulated format to expedite their use in practice
Rapid-response radio observations of short GRB 181123B with the Australia Telescope Compact Array
We introduce the Australia Telescope Compact Array (ATCA) rapid-response mode
by presenting the first successful trigger on the short-duration gamma-ray
burst (GRB) 181123B. Early-time radio observations of short GRBs may provide
vital insights into the radio afterglow properties of Advanced LIGO- and
Virgo-detected gravitational wave events, which will in turn inform follow-up
strategies to search for counterparts within their large positional
uncertainties. The ATCA was on target within 12.6 hr post-burst, when the
source had risen above the horizon. While no radio afterglow was detected
during the 8.3 hr observation, we obtained force-fitted flux densities of and Jy at 5.5 and 9 GHz, respectively. Afterglow
modelling of GRB 181123B showed that the addition of the ATCA force-fitted
radio flux densities to the Swift X-ray Telescope detections provided more
stringent constraints on the fraction of thermal energy in the electrons
(log rather than log derived without the inclusion of the ATCA values), which
is consistent with the range of typical derived from GRB afterglow
modelling. This allowed us to predict that the forward shock may have peaked in
the radio band days post-burst, producing detectable radio emission
days post-burst. Overall, we demonstrate the potential for
extremely rapid radio follow-up of transients and the importance of triggered
radio observations for constraining GRB blast wave properties, regardless of
whether there is a detection, via the inclusion of force-fitted radio flux
densities in afterglow modelling efforts
Influência do Hormônio do Crescimento na concentração de testosterona plasmática e nas características seminais de touros jovens e adultos da raça Nelore
Genome-Wide Joint Meta-Analysis of SNP and SNP-by-Smoking Interaction Identifies Novel Loci for Pulmonary Function
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