134 research outputs found
High resolution infrared absorption spectra, crystal field, and relaxation processes in CsCdBr_3:Pr^3+
High resolution low-temperature absorption spectra of 0.2% Pr^3+ doped
CsCdBr_3 were measured in the spectral region 2000--7000 cm-1. Positions and
widths of the crystal field levels within the 3H5, 3H4, 3F2, and 3F3 multiplets
of the Pr^3+ main center have been determined. Hyperfine structure of several
spectral lines has been found. Crystal field calculations were carried out in
the framework of the semiphenomenological exchange charge model (ECM).
Parameters of the ECM were determined by fitting to the measured total
splittings of the 3H4 and 3H6 multiplets and to the observed in this work
hyperfine splittings of the crystal field levels. One- and two-phonon
relaxation rates were calculated using the phonon Green's functions of the
perfect (CsCdBr_3) and locally perturbed (impurity dimer centers in
CsCdBr_3:Pr^3+) crystal lattice. Comparison with the measured linewidths
confirmed an essential redistribution of the phonon density of states in
CsCdBr_3 crystals doped with rare-earth ions.Comment: 16 pages, 5 tables, 3 figure
Western Irish Sea Nephrops Grounds (FU15) 2017 UWTV Survey Report and catch options for 2018
This report provides the main results and findings of the 15th annual underwater television survey on the âIrish sea west Nephrops groundsâ ICES assessment area, Functional Unit 15. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. The 2017 design consisted of a randomised isometric grid of 100 stations at 4.5 nautical mile intervals out over the full known extent the stock. The resulting krigged burrow abundance estimate was 5.3 billion burrows. This was a similar result of that obtained in 2006, and 4% higher than the abundance in 2016. In contrast to 2016 the spatial distribution of burrows appears more homogenous across the survey area. Overall densities are high and abundance remains stable, well above MSY Btrigger. Reducing the number of stations compared to 2011 has not affected the accuracy of the survey estimate to date. The CV (or relative standard error) of 3% is in line with previous estimates and well below the upper limit of 20% recommended by SGNEPS 2012. Total catches and landings options at various different fishing mortalities were calculated and fishing at Fmsy in 2017 implies a total catch option at Fmsy (=Fmax) of 11,807 tonnes which results in landings of no more than 9,630 tonnes. The only sea-pen species observed in 2017 was Virgularia mirabilis and this was found at 16% of stations ranging from occasional to common, with high densities observed in the south-west of the ground. Trawl marks were noted at 36% of the UWTV stations
Western Irish Sea Nephrops Grounds (FU15) 2013 UWTV Survey Report and catch options for 2014
Use the URI link below to search the Marine Institute Data Discovery Catalogue for datasets relevant to this report.This report provides the main results and findings of the eleventh annual underwater television survey on the âIrish sea west Nephrops groundsâ ICES assessment area, Functional Unit 15. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. The 2013 design consisted of a randomised isometric grid of 80 stations at 5 nautical mile intervals out over the full known extent the stock. The resulting krigged burrow abundance estimate was 4.3 billion burrows. This was a 16% decrease relative to 2012. The spatial distribution shows higher abundance in the south of the area and a larger decline in abundance is apparent in the North. Overall densities remain high and abundance remains relatively stable, well above MSY Btrigger. Reducing the number of stations in 2013 is not expected to have significantly affected the accuracy of the survey estimate. The CV (or relative standard error) of 3% is in line with previous estimates and well below the upper limit of 20% recommended by SGNEPS 2012. Total catches and landings options at various different fishing mortalities were calculated and fishing at Fmsy in 2014 implies a total catch option at Fmsy (=Fmax) of 9,914 tonnes which results in landings of no more than 8,244 tonnes. The only sea-pen species observed in 2013 was Virgularia mirabilis and the frequency of occurrence was lower than in 2012. Trawl marks were noted at 43% of the UWTV stations
Western Irish Sea Nephrops Grounds (FU15) 2014 UWTV Survey Report and catch options for 2015
This report provides the main results and findings of the 12th annual underwater television survey on the âIrish sea west Nephrops groundsâ ICES assessment area, Functional Unit 15. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. The 2014 design consisted of a randomised isometric grid of 101 stations at 4.5 nautical mile intervals out over the full known extent the stock. The resulting krigged burrow abundance estimate was 4.6 billion burrows. This was a similar result of that obtained in 2009, and slightly higher than the abundance in 2013. The spatial distribution shows a decline in abundance in the south-eastern area compared to 2013 figure, while a slight increase is apparent in the North and in the middle of the area. Overall densities remain high and abundance remains relatively stable, well above MSY Btrigger. Reducing the number of stations compared to 2011 is not expected to have significantly affected the accuracy of the survey estimate. The CV (or relative standard error) of 3% is in line with previous estimates and well below the upper limit of 20% recommended by SGNEPS 2012. Total catches and landings options at various different fishing mortalities were calculated and fishing at Fmsy in 2015 implies a total catch option at Fmsy (=Fmax) of 9,922 tonnes which results in landings of no more than 8,223 tonnes. The only sea-pen species observed in 2014 was Virgularia mirabilis and the frequency of occurrence was lower than the average during the investigated period, but higher than in 2013. Trawl marks were noted at 24% of the UWTV stations
Western Irish Sea Nephrops Grounds (FU15) 2019 UWTV Survey Report and catch options for 2020
This report provides the main results and findings of the 17th annual underwater
television survey on the âIrish sea west Nephrops groundsâ ICES assessment area,
Functional Unit 15. The survey was multi-disciplinary in nature collecting UWTV and
other ecosystem data. The 2019 design consisted of a randomised isometric grid of 100
stations at 4.5 nautical mile intervals out over the full known extent the stock. The
resulting krigged burrow abundance estimate was 4.4 billion burrows. This was a
similar result of that obtained in 2015, but a 10% lower than the abundance in 2018. In
contrast to 2017 the spatial distribution of burrows shows a high density band on the
central western area of the survey ground. The abundance remains within previously
observed ranges and is above MSY Btrigger. The CV (or relative standard error) of 3% is
in line with previous estimates and well below the upper limit of 20% recommended by
SGNEPS 2012. Total catches and landings options at various different fishing
mortalities were calculated and fishing at Fmsy in 2020 implies a total catch option at
Fmsy (=Fmax) of 10,377 tonnes estimated to result in landings of no more than 8,546
tonnes. Sea-pens were observed at 21% of stations with high densities observed in the
south-west of the ground. Trawl marks were noted at 15% of the UWTV stations
The Golden Meteorite Fall: Fireball Trajectory, Orbit and Meteorite Characterization
The Golden (British Columbia, Canada) meteorite fall occurred on Oct 4, 2021
at 0534 UT with the first recovered fragment (1.3 kg) landing on an occupied
bed. The meteorite is an unbrecciated, low-shock (S2) ordinary chondrite of
intermediate composition, typed as an L/LL5. From noble gas measurements the
cosmic ray exposure age is 25 Ma while gas retention ages are all >2 Ga.
Short-lived radionuclides and noble gas measurements of the pre-atmospheric
size overlap with estimates from infrasound and lightcurve modelling producing
a preferred pre-atmospheric mass of 70-200 kg. The orbit of Golden has a high
inclination (23.5 degs) and is consistent with delivery from the inner main
belt. The highest probability (60%) of an origin is from the Hungaria group. We
propose that Golden may originate among the background S-type asteroids found
interspersed in the Hungaria region. The current collection of 18 L and LL
chondrite orbits shows a strong preference for origins in the inner main belt,
suggesting multiple parent bodies may be required to explain the diversity in
CRE ages and shock states.Comment: 92 Pages, 20 Tables, 21 Figures, plus 3 appendices, accepted in
Meteoritics and Planetary Science Oct 26 202
Western Irish Sea Nephrops Grounds (FU15) 2018 UWTV Survey Report and catch options for 2019
This report provides the main results and findings of the 16th annual underwater television survey on the âIrish sea west Nephrops groundsâ ICES assessment area, Functional Unit 15. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. The 2018 design consisted of a randomised isometric grid of 100 stations at 4.5 nautical mile intervals out over the full known extent the stock. The resulting krigged burrow abundance estimate was 4.9 billion burrows. This was a similar result of that obtained in 2011, and 9% lower than the abundance in 2017. In contrast to 2017 the spatial distribution of burrows appears more homogenous across the survey area, with high densities in the SW of the ground in shallower water, and higher densities in the NW of the ground in deep water. Overall densities are high and abundance remains stable, well above MSY Btrigger. Reducing the number of stations compared to 2011 has not affected the accuracy of the survey estimate to date. The CV (or relative standard error) of 3% is in line with previous estimates and well below the upper limit of 20% recommended by SGNEPS 2012. Total catches and landings options at various different fishing mortalities were calculated and fishing at Fmsy in 2018 implies a total catch option at Fmsy (=Fmax) of 11,107 tonnes which results in landings of no more than 8,959 tonnes. The sea-pen species observed in 2018 was predominantly Virgularia mirabilis, with one potential observation of Pennatula phosphorea (which requires verification). Sea-pens were observed at 20% of stations with high densities observed in the south-west of the ground. Trawl marks were noted at 26% of the UWTV stations
Spectrum, risk factors and outcomes of neurological and psychiatric complications of COVID-19: a UK-wide cross-sectional surveillance study.
SARS-CoV-2 is associated with new-onset neurological and psychiatric conditions. Detailed clinical data, including factors associated with recovery, are lacking, hampering prediction modelling and targeted therapeutic interventions. In a UK-wide cross-sectional surveillance study of adult hospitalized patients during the first COVID-19 wave, with multi-professional input from general and sub-specialty neurologists, psychiatrists, stroke physicians, and intensivists, we captured detailed data on demographics, risk factors, pre-COVID-19 Rockwood frailty score, comorbidities, neurological presentation and outcome. A priori clinical case definitions were used, with cross-specialty independent adjudication for discrepant cases. Multivariable logistic regression was performed using demographic and clinical variables, to determine the factors associated with outcome. A total of 267 cases were included. Cerebrovascular events were most frequently reported (131, 49%), followed by other central disorders (95, 36%) including delirium (28, 11%), central inflammatory (25, 9%), psychiatric (25, 9%), and other encephalopathies (17, 7%), including a severe encephalopathy (nâ=â13) not meeting delirium criteria; and peripheral nerve disorders (41, 15%). Those with the severe encephalopathy, in comparison to delirium, were younger, had higher rates of admission to intensive care and a longer duration of ventilation. Compared to normative data during the equivalent time period prior to the pandemic, cases of stroke in association with COVID-19 were younger and had a greater number of conventional, modifiable cerebrovascular risk factors. Twenty-seven per cent of strokes occurred in patients 60âyears old, the younger stroke patients presented with delayed onset from respiratory symptoms, higher rates of multi-vessel occlusion (31%) and systemic thrombotic events. Clinical outcomes varied between disease groups, with cerebrovascular disease conferring the worst prognosis, but this effect was less marked than the pre-morbid factors of older age and a higher pre-COVID-19 frailty score, and a high admission white cell count, which were independently associated with a poor outcome. In summary, this study describes the spectrum of neurological and psychiatric conditions associated with COVID-19. In addition, we identify a severe COVID-19 encephalopathy atypical for delirium, and a phenotype of COVID-19 associated stroke in younger adults with a tendency for multiple infarcts and systemic thromboses. These clinical data will be useful to inform mechanistic studies and stratification of patients in clinical trials
Joint Bayesian Analysis of Parameters and States in Nonlinear, Non-Gaussian State Space Models
Stakeholdersâ perceptions of the benefit of introducing an Australian Intermediary System for vulnerable witnesses
Vulnerable witnesses (e.g. children and adults with communication impairment) face many barriers to testifying and achieving justice when participating in the criminal justice system. To date, reforms have been implemented in Australia to address these, yet the barriers remain. Several other countries have implemented an intermediary scheme, whereby an independent third party assists vulnerable witnesses to understand the questions and processes encountered during interviews and trials, and helps witnesses to be understood. This study provides a qualitative analysis of stakeholdersâ (NÂŒ25 professionals) perceptions regarding the potential benefits of implementing an intermediary scheme in Australia. While all participants demonstrated an open-minded attitude to new reform in this area, their perspectives did not support the introduction of an intermediary scheme at this time. Stakeholders highlighted the need for improved use and effectiveness of current measures, and expressed concern about adding further complication to the system
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