Explicit correlation and basis set superposition error: The structure and energy of carbon dioxide dimer

We have investigated the slipped parallel and t-shaped structures of carbon dioxide dimer [(CO₂)₂] using both conventional and explicitly correlated coupled cluster methods, inclusive and exclusive of counterpoise (CP) correction. We have determined the geometry of both structures with conventional coupled cluster singles doubles and perturbative triples theory [CCSD(T)] and explicitly correlated cluster singles doubles and perturbative triples theory [CCSD(T)-F12b] at the complete basis set (CBS) limits using custom optimization routines. Consistent with previous investigations, we find that the slipped parallel structure corresponds to the global minimum and is 1.09 kJ mol⁻¹ lower in energy. For a given cardinal number, the optimized geometries and interaction energies of (CO₂)₂ obtained with the explicitly correlated CCSD(T)-F12b method are closer to the CBS limit than the corresponding conventional CCSD(T) results. Furthermore, the magnitude of basis set superposition error (BSSE) in the CCSD(T)-F12b optimized geometries and interaction energies is appreciably smaller than the magnitude of BSSE in the conventional CCSD(T) results. We decompose the CCSD(T) and CCSD(T)-F12b interaction energies into the constituent HF or HF CABS, CCSD or CCSD-F12b, and (T) contributions. We find that the complementary auxiliary basis set (CABS) singles correction and the F12b approximation significantly reduce the magnitude of BSSE at the HF and CCSD levels of theory, respectively. For a given cardinal number, we find that non-CP corrected, unscaled triples CCSD(T)-F12b/VXZ-F12 interaction energies are in overall best agreement with the CBS limit

Measured electron contribution to Shuttle plasma environment: Abbreviated update

The differential energy spectra of electrons between 1 and 100 eV were measured by an electron spectrometer flown on an early shuttle. This energy range was scanned in 64 incremental steps with a resolution of 7%. The most striking feature that was observed throughout these spectra was a relatively flat distribution of the higher energy electrons out to 100 eV. This is in contrast to normal ambient spectra which consistently show a rapid decline in quantitative flux beyond 50 to 55 eV. The lower energy (1 to 2 eV) end of these spectra showed steep thermal trails comparable to normal ambient spectral structure. In general, daytime fluxes were significantly higher than those obtained during nighttime measurements. Quantitative flux excursions which may possibly be associated with thruster firing were frequently observed. Spectral structure suggestive of the N2 vibrational excitation energy loss mechanism was also seen in the data from some measurement periods. Examples of these spectra are shown and possible correlations are discussed

Trends of oral cavity, oropharyngeal and laryngeal cancer incidence in Scotland (1975 - 2012) - a socioeconomic perspective

Aim: To examine current incidence trends (1975–2012) of oral cavity (OCC), oropharyngeal (OPC) and laryngeal cancer in Scotland by socioeconomic status (SES). Methods: We included all diagnosed cases of OCC (C00.3-C00.9, C02-C06 excluding C2.4), OPC (C01, C2.4, C09-C10, C14) and laryngeal cancer (C32) on the Scottish Cancer Registry (1975–2012) and annual midterm population estimates by age, sex, geographic region and SES indices (Carstairs 1991 and Scottish Index of Multiple Deprivation 2009). Age-standardized incidence rates were computed and adjusted Poisson regression rate-ratios (RR) compared subsites by age, sex, region, SES and year of diagnosis. Results: We found 28,217 individuals (19,755 males and 8462 females) diagnosed with head and neck cancer (HNC) over the study period. Between 1975 and 2012, relative to the least deprived areas, those living in the most deprived areas exhibited the highest RR (>double) of OCC, OPC and laryngeal cancer, and an almost dose-like response was observed between SES and HNC incidence. Between 2001 and 2012, this socioeconomic inequality tended to increase over time for OPC and laryngeal cancer but remained relatively unchanged for OCC. Incidence rates increased markedly for OPC, decreased for laryngeal cancer and remained stable for OCC, particularly in the last decade. Males exhibited significantly higher RRs compared to females, and the peak age of incidence of OPC was slightly lower than the other subsites. Conclusion: Contrary to reports that OPC exhibits an inverse socioeconomic profile, Scotland country-level data show that those from the most deprived areas consistently have the highest rates of head and neck cancers

HST imaging of hyperluminous infrared galaxies

We present HST WFPC2 I band imaging for a sample of 9 Hyperluminous Infrared Galaxies spanning a redshift range 0.45 < z < 1.34. Three of the sample have morphologies showing evidence for interactions, six are QSOs. Host galaxies in the QSOs are reliably detected out to z ~ 0.8. The detected QSO host galaxies have an elliptical morphology with scalelengths spanning 6.5 < r_{e}(Kpc) < 88 and absolute k corrected magnitudes spanning -24.5 < M_{I} < -25.2. There is no clear correlation between the IR power source and the optical morphology. None of the sources in the sample, including F15307+3252, show any evidence for gravitational lensing. We infer that the IR luminosities are thus real. Based on these results, and previous studies of HLIRGs, we conclude that this class of object is broadly consistent with being a simple extrapolation of the ULIRG population to higher luminosities; ULIRGs being mainly violently interacting systems powered by starbursts and/or AGN. Only a small number of sources whose infrared luminosities exceed 10^{13}Lsun are intrinsically less luminous objects which have been boosted by gravitational lensing.Comment: 16 Pages. Accepted for publication in MNRA

Gas Analysis by Absorption

There is practically only one method of gas analysis. This was worked out many years ago by Bunsen, Hempel, and Winkler and consists in the successive absorption with different chemicals of the various constituents of the gas. The only improvement to this method is the oxidation and combustion of different components of a mixture followed by absorption

Evaluation of dental therapists undertaking dental examinations in a school setting in Scotland

Objective: To measure agreement between dental therapists and the Scottish gold-standard dentist undertaking National Dental Inspection Programme (NDIP) examinations. Methods: A study of interexaminer agreement between 19 dental therapists and the national gold-standard dentist was carried out. Pre-calibration training used the caries diagnostic criteria and examination techniques agreed by the British Association for the Study of Community Dentistry (BASCD). Twenty-three 5-year-old children (Primary 1) and 17 11-year-old children (Primary 7) children were examined. Agreement was assessed using kappa statistics on d 3 mft and D 3 MFT for P1 and P7 children, sensitivity and specificity values, and kappa statistics on d 3 t/D 3 T and ft/FT. Calibration data on P1 and P7 children from 2009–2012 involving dentists as examiners were used for comparison. Economic evaluation was undertaken using a cost minimization analysis approach. Results: The mean kappa score was 0.84 (SD 0.07) ranging from 0.69 to 0.94. All dental therapists scored good or very good agreement with the gold-standard dentist. This compares with historic NDIP calibration data with dentists, against the same gold-standard dentist, where the mean kappa value was 0.68 (SD 0.22) with a range of 0.35-1.00. The mean sensitivity score was 0.98 (SD 0.04) (range 0.88-1.0) and mean specificity score was 0.90 (SD 0.06) (range 0.78-0.96). Health economic analysis estimated that salary costs would be 33.6% lower if dental therapists were substituted for dentists in the year 2013, with an estimated saving of approximately £103 646 per annum on the national budget. Conclusion: We conclude that dental therapists show a high level of interexaminer agreement, and with the appropriate annual training and calibration, they could undertake dental examinations as part of the NDIP programme

The X-ray Spectrum of the z=6.30 QSO SDSS J1030+0524

We present a deep XMM-Newton observation of the z=6.30 QSO SDSS J1030+0524, the second most distant quasar currently known. The data contain sufficient counts for spectral analysis, demonstrating the ability of XMM-Newton to measure X-ray spectral shapes of z~6 QSOs with integration times >100ks. The X-ray spectrum is well fit by a power law with index Gamma=2.12 +/- 0.11, an optical-X-ray spectral slope of a_{ox}=-1.80, and no absorption excess to the Galactic value, though our data are also consistent with a power law index in the range 2.02 < Gamma < 2.5 and excess absorption in the range 0 < N_H(cm^-2) < 8x10^22. There is also a possible detection (2 sigma) of FeKa emission. The X-ray properties of this QSO are, overall, similar to those of lower-redshift radio-quiet QSOs. This is consistent with the statement that the X-ray properties of radio-quiet QSOs show no evolution over 0<z<6.3. Combined with previous results, this QSO appears indistinguishable in any way from lower redshift QSOs, indicating that QSOs comparable to those seen locally existed less than one Gyr after the Big Bang.Comment: ApJ Letters, accepte

Automation of shear-wave splitting parameter determination of local earthquakes at Yellowstone : application as indicator of crustal stress and temporal variation

Shear-wave splitting can be a useful technique for determining crustal stress fields in volcanic settings and temporal variations associated with activity. Splitting parameters were determined for a subset of local earthquakes recorded from 2000-2010 at Yellowstone. Analysis was automated using an unsupervised cluster analysis technique to determine optimum splitting parameters from 270 analysis windows for each event. Six stations clearly exhibit preferential fast polarization values sub-orthogonal to the direction of minimum horizontal compression. Yellowstone deformation results in a local crustal stress field differing from the regional field dominated by NE-SW extension, and fast directions reflect this difference rotating around the caldera maintaining perpendicularity to the rim. One station exhibits temporal variations concordant with identified periods of caldera subsidence and uplift. From splitting measurements, we calculated a crustal anisotropy of ~17-23% and crack density ~0.12-0.17 possibly resulting from stress-aligned fluid filled microcracks in the upper crust and an active hydrothermal system