AN INTRODUCTION TO THE NMFS MARINE RECREATIONAL FISHERIES STATISTICS SURVEY WITH AN EMPHASIS ON ECONOMIC VALUATION

Resource /Energy Economics and Policy,

Changing experience with dual chamber (DDD) pacemakers

Dual chamber (DDD) or “universal” pacemakers have had a significant impact on the advancement of artificial pacemakers by providing a more physiologic approach to cardiac pacing. However, with the early generation of DDD pacemakers (pacemakers that sense and pace in both the atrium and the ventricle), a significant number of patients experienced pacemaker-mediated tachycardia because intact ventriculoatrial conduction was sensed in the atrium and a reentrant tachycardia was induced. Newer generation DDD pacemakers have provided longer atrial refractory periods, which should correct this problem.In this study the first and second years of a 2 year experience with DDD pacemakers were compared to determine if the newer generation devices have allowed maintenance of pacing in the DDD mode as opposed to reprogramming to some alternate mode because of pacemaker-mediated tachycardia or other pacing problems. The results showed a significant decrease in pacemaker-mediated tachycardia during the second year and continuation of pacing in the DDD mode in a higher percent of patients. This improvement is attributed to improvement in the pulse generator as well as better patient selection

Temperature Dependence Of The Electronic Absorption Spectrum Of NO2

The nitrogen dioxide (NO2) radical is composed of the two most abundant elements in the atmosphere, where it can be formed in a variety of ways including combustion, detonation of energetic materials, and lightning. Relevant also to smog and ozone cycles, together these processes span a wide range of temperatures. Remarkably, high-resolution NO2 electronic absorption spectra have only been reported in a narrow range below about 300 K. Previously, we reported [ J. Phys. Chem. A 2021, 125, 5519−5533 ] the construction of quasi-diabatic potential energy surfaces (PESs) for the lowest four electronic states (X̃, Ã, B̃, and C̃) of NO2. In addition to three-dimensional PESs based on explicitly correlated MRCI(Q)-F12/VTZ-F12 ab initio data, the geometry dependence of each component of the dipoles and transition dipoles was also mapped into fitted surfaces. The multiconfigurational time-dependent Hartree (MCTDH) method was then used to compute the 0 K electronic absorption spectrum (from the ground rovibrational initial state) employing those energy and transition dipole surfaces. Here, in an extension of that work, we report an investigation into the effects of elevated temperature on the spectrum, considering the effects of the population of rotationally and vibrationally excited initial states. The calculations are complemented by new experimental measurements. Spectral contributions from hundreds of rotational states up to N = 20 and from 200 individually-characterized vibrational states were computed. A spectral simulation tool was developed that enables modeling the spectrum at various temperatures─by weighting individual spectral contributions via the partition function, or for pure excited initial states, which can be probed via transient absorption spectroscopy. We validate these results against experimental absorption spectroscopy data at high temperatures, as well as via a new measurement from the (1,0,1) initial vibrational state

Design of Lightweight Fills for Road Embankments on Boston\u27s Central Artery/Tunnel Project

The use of lightweight-fill materials for highway construction increased significantly worldwide during the 1990s. Predominant with this trend was the increased use of cellular geosynthetics (geofoams and geocombs), especially block-molded expanded polystyrene (EPS) geofoam, on highway and bridge embankments. EPS geofoam is increasingly recognized as an important tool for reducing overall cost of highways through accelerated construction . Thus, it was appropriate that lightweight-fill materials, mostly EPS, were the materials of choice on Boston’s Central Artery/Tunnel (CA/T) Project, commonly known as the Big Dig . EPS highway embankments have been constructed, as part of a cost-and schedule-initiative, replacing the original design concepts for eight transition highway structures on a recent CA/T construction contract. The use of EPS-block geofoam on the CA/T included the first-time implementation of newly developed NCHRP research and AASHTO based design guidelines, material/product specifications as well as formulating innovative solutions to several technical challenges. These challenges centered on relatively tall and slender EPS fills placed over soft soils subjected to periodic flooding and seismic loading within a crowded urban environment. This paper presents a detailed outline of the design process together with the impacts of the buoyancy conditions and seismic loading on the design of EPS highway embankments. Also included is a discussion of other lightweight-fill materials such as geocombs (considered but not used) and expanded-shale aggregate (used in limited quantities)

Incidence and associations of hospital delirium diagnoses in 85979 people with severe mental illness: a data linkage study

INTRODUCTION: Delirium is an acute neuro-psychiatric disturbance precipitated by a range of physical stressors, with high morbidity and mortality. Little is known about its relationship with severe mental illness (SMI). METHODS: We conducted a retrospective cohort study using linked data analyses of the UK Clinical Practice Research Datalink (CPRD) and Hospital Episodes Statistics (HES) databases. We ascertained yearly hospital delirium incidence from 2000 - 2017 and used logistic regression to identify associations with delirium diagnosis in a population with severe mental illness. RESULTS: The cohort included 249,047 people with severe mental illness with median follow-up time in CPRD of 6.4 years. 85,979 patients were eligible for linkage to HES. Delirium incidence increased from 0.04 (95% CI 0.02 - 0.07) delirium associated admissions per 100 person-years in 2000 to 1.05 (95% CI 0.93 - 1.17) per 100 person-years in 2017, increasing most notably from 2010 onwards. Delirium was associated with older age at study entry (OR 1.05 per year, 95% CI 1.05-1.06), SMI diagnosis of bipolar affective disorder (OR 1.66, 95% CI 1.44 - 1.93) or other psychosis (OR 1.56, 95% CI 1.35 - 1.80) relative to schizophrenia, and more physical comorbidities (OR 1.08 per additional comorbidity of the Charlson Comorbidity Index, 95% CI 1.02 - 1.14). Patients with delirium received more antipsychotic medication during follow-up (1-2 antipsychotics OR 1.65, 95% CI 1.44 - 1.90; >2 antipsychotics OR 2.49, 95% CI 2.12 - 2.92). CONCLUSIONS: The incidence of recorded delirium diagnoses in people with severe mental illness has increased in recent years. Older people prescribed more antipsychotics and with more comorbidities have a higher incidence. Linked electronic health records are feasible for exploring hospital diagnoses such as delirium in SMI

Flow tube studies of the C(3P) reactions with ethylene and propylene

International audienceProduct detection studies of C(3P) atom reactions with ethylene, C2H4(X1Ag) and propylene, C3H6(X1A′) are carried out in a flow tube reactor at 332 K and 4 Torr (553.3 Pa) under multiple collision conditions. Ground state carbon atoms are generated by 193 nm laser photolysis of carbon suboxide, C3O2 in a buffer of helium. Thermalized reaction products are detected using tunable VUV photoionization and time of flight mass spectrometry. For C(3P) + ethylene, propargyl (C3H3) is detected as the only molecular product in agreement with previous studies on this reaction. The temporal profiles of the detected ions are used to discriminate C(3P) reaction products from side reaction products. For C(3P) + propylene, two reaction channels are identified through the detection of methyl (CH3) and propargyl (C3H3) radicals for the first channel and C4H5 for the second one. Franck–Condon Factor simulations are employed to infer the C4H5-isomer distribution. The measured 1:4 ratio for the i-C4H5 isomer relative to the methylpropargyl isomers is similar to the C4H5 isomer distribution observed in low-pressure flames and differs from crossed molecular beams data. The accuracy of these isomer distributions is discussed in view of large uncertainties on the photoionization spectra of the pure C4H5 isomer

Support received after bereavement by suicide and other sudden deaths:a cross-sectional UK study of 3,432 young bereaved adults

OBJECTIVE: To test the hypothesis that people bereaved by suicide are less likely to receive formal or informal support than people bereaved by other causes of sudden death. DESIGN: National cross-sectional study. SETTING: Adults working or studying at any UK higher education institution (HEI) in 2010. PARTICIPANTS: A total of 3432 eligible respondents aged 18-40 years bereaved by the sudden death of a close friend or relative, sampled from approximately 659 572 bereaved and non-bereaved staff and students at 37 of 164 UK HEIs invited to participate. EXPOSURES: Bereavement by suicide (n=614; 18%), by sudden unnatural causes (n=712; 21%) and by sudden natural causes (n=2106; 61%). MAIN OUTCOME MEASURES: Receipt of formal and informal support postbereavement; timing of valued support. RESULTS: 21% (725/3432) of our sample of bereaved adults reported receiving no formal or informal bereavement support, with no evidence for group differences. People bereaved by suicide were less likely to have received informal support than those bereaved by sudden natural causes (adjusted OR (AOR)=0.79; 95% CI 0.64 to 0.98) or unnatural causes (AOR=0.74; 95% CI 0.58 to 0.96) but did not differ from either comparison group on receipt of formal support. People bereaved by suicide were less likely to have received immediate support (AOR=0.73; 95% CI 0.59 to 0.90) and more likely to report delayed receipt of support (AOR=1.33; 95% CI 1.08 to 1.64) than people bereaved by sudden natural causes. Associations were not modified by gender, or age bereaved, but became non-significant when adjusting for stigma. CONCLUSIONS: People bereaved by suicide are less likely to receive informal support than people bereaved by other causes of sudden death and are more likely to perceive delays in accessing any support. This is concerning given their higher risk of suicide attempt and the recommendations within suicide prevention strategies regarding their need for support. STUDY REGISTRATION: http://www.ucl.ac.uk/psychiatry/bereavementstudy/

Vacuum ultraviolet photoionization cross section of the hydroxyl radical

The absolute photoionization spectrum of the hydroxyl (OH) radical from 12.513 to 14.213 eV was measured by multiplexed photoionization mass spectrometry with time-resolved radical kinetics. Tunable vacuum ultraviolet (VUV) synchrotron radiation was generated at the Advanced Light Source. OH radicals were generated from the reaction of O(^1D) + H_2O in a flow reactor in He at 8 Torr. The initial O(^1D) concentration, where the atom was formed by pulsed laser photolysis of ozone, was determined from the measured depletion of a known concentration of ozone. Concentrations of OH and O(^3P) were obtained by fitting observed time traces with a kinetics model constructed with literature rate coefficients. The absolute cross section of OH was determined to be σ(13.436 eV) = 3.2 ± 1.0 Mb and σ(14.193 eV) = 4.7 ± 1.6 Mb relative to the known cross section for O(^3P) at 14.193 eV. The absolute photoionization spectrum was obtained by recording a spectrum at a resolution of 8 meV (50 meV steps) and scaling to the single-energy cross sections. We computed the absolute VUV photoionization spectrum of OH and O(^3P) using equation-of-motion coupled-cluster Dyson orbitals and a Coulomb photoelectron wave function and found good agreement with the observed absolute photoionization spectra