Call for a new classification system and treatment strategy in blunt aortic injury

ObjectiveThe current Society for Vascular Surgery (SVS) classification scheme for blunt aortic injury (BAI) is descriptive but does not guide therapy. We propose a simplified classification scheme based on our robust experience with BAI that is descriptive and guides therapy.MethodsPatients presenting with BAI between January 1999 and September 2014 were identified from our institution's trauma registry. We divided patients into eras by time. Era 1: before the first United States Food and Drug Administration (FDA)-approved thoracic endovascular aortic repair (TEVAR) device (1999-2005); era 2: FDA-approved TEVAR devices (2005-2010); and era 3: FDA-approved BAI-specific devices (2010-present). Baseline demographic information, Injury Severity Score, hospital details, and survival were collected and compared. Our classification scheme was minimal aortic injury, SVS grade 1 and 2; moderate aortic injury, SVS grade 3; and severe aortic injury, SVS grade 4.ResultsWe identified 226 patients with a diagnosis of BAI: 75 patients in era 1, 84 in era 2, and 67 in era 3. Mean Injury Severity Score was 39.5 (range, 16-75). The BAI-related in-hospital mortality was significantly higher before endovascular introduction in era 1 (14.6% vs 4.8%; P = .03), but was not significantly different between eras 2 and 3 or before and after BAI-specific devices were introduced (P = .43). Of 146 patients (64.6%) who underwent aortic intervention, 91 underwent endovascular repair, and 55 underwent open repair. All but nine patients (94%) had a moderate or severe injury. Survival across all three eras of patients undergoing operative intervention was 80.2%. Survival in eras 2 and 3 was higher than in era 1 (86.4% vs 73.8%) but was not significant (P = .38). Of 47 patients in eras 2 and 3 with minimal aortic injury, 45 (96%) were managed nonoperatively, with no BAI-related deaths. After 2007, follow-up imaging was obtained in 38 patients (80%) with minimal aortic injury, and progression was not observed. Computed tomography scans showed the injury in 13 patients appeared stable, 19 had complete resolution (50%), and 6 had a decreasing size of injury.ConclusionsOur experience confirms that BAI-related mortality for patients who survive to presentation is now 5%. From our findings during the past 15 years, we propose simplification of the SVS grading criteria of BAI into minimal, moderate, and severe based on treatment differences among the three groups. Minimal aortic injury can be successfully managed nonoperatively without mandatory follow-up imaging. Moderate aortic injury can be managed semielectively with TEVAR, and severe aortic injury, requires emergency TEVAR

The migration of nearby spirals from the blue to red sequence: AGN feedback or environmental effects?

We combine ultraviolet to near-infrared photometry with HI 21cm line observations for a complete volume-limited sample of nearby galaxies in different environments (from isolated galaxies to Virgo cluster members), to study the migration of spirals from the blue to the red sequence. Although our analysis confirms that, in the transition region between the two sequences, a high fraction of spirals host active galactic nuclei (AGN), it clearly shows that late-types with quenched star formation are mainly HI deficient galaxies preferentially found in the Virgo cluster. This not only suggests that environmental effects could play a significant role in driving the migration of local galaxies from the blue sequence, but it also implies that a physical link between AGN feedback and quenching may not be assumed from a correlation between nuclear activity and colour.Comment: Accepted for publication in MNRAS. 6 pages, 1 figur

Detectors and cryostat design for the SuMIRe Prime Focus Spectrograph (PFS)

We describe the conceptual design of the camera cryostats, detectors, and detector readout electronics for the SuMIRe Prime Focus Spectrograph (PFS) being developed for the Subaru telescope. The SuMIRe PFS will consist of four identical spectrographs, each receiving 600 fibers from a 2400 fiber robotic positioner at the prime focus. Each spectrograph will have three channels covering wavelength ranges 3800 {\AA} - 6700 {\AA}, 6500 {\AA} - 10000 {\AA}, and 9700 {\AA} - 13000 {\AA}, with the dispersed light being imaged in each channel by a f/1.10 vacuum Schmidt camera. In the blue and red channels a pair of Hamamatsu 2K x 4K edge-buttable CCDs with 15 um pixels are used to form a 4K x 4K array. For the IR channel, the new Teledyne 4K x 4K, 15 um pixel, mercury-cadmium-telluride sensor with substrate removed for short-wavelength response and a 1.7 um cutoff will be used. Identical detector geometry and a nearly identical optical design allow for a common cryostat design with the only notable difference being the need for a cold radiation shield in the IR camera to mitigate thermal background. This paper describes the details of the cryostat design and cooling scheme, relevant thermal considerations and analysis, and discusses the detectors and detector readout electronics

The clustering of massive galaxies at z~0.5 from the first semester of BOSS data

We calculate the real- and redshift-space clustering of massive galaxies at z~0.5 using the first semester of data by the Baryon Oscillation Spectroscopic Survey (BOSS). We study the correlation functions of a sample of 44,000 massive galaxies in the redshift range 0.4<z<0.7. We present a halo-occupation distribution modeling of the clustering results and discuss the implications for the manner in which massive galaxies at z~0.5 occupy dark matter halos. The majority of our galaxies are central galaxies living in halos of mass 10^{13}Msun/h, but 10% are satellites living in halos 10 times more massive. These results are broadly in agreement with earlier investigations of massive galaxies at z~0.5. The inferred large-scale bias (b~2) and relatively high number density (nbar=3e-4 h^3 Mpc^{-3}) imply that BOSS galaxies are excellent tracers of large-scale structure, suggesting BOSS will enable a wide range of investigations on the distance scale, the growth of large-scale structure, massive galaxy evolution and other topics.Comment: 11 pages, 12 figures, matches version accepted by Ap

Study of galaxies in the Lynx-Cancer void. -- III. New extreme LSB dwarf galaxies

(Abridged) We present the results of the complex study of the low surface brightness dwarf (LSBD) gas-rich galaxies J0723+3621, J0737+4724 and J0852+1350, which reside in the nearby Lynx-Cancer void. Their ratios M(HI)/L_B, according to HI data obtained with the NRT, are respectively ~3.9, ~2, ~2.6. For the two latter galaxies, we derived oxygen abundance corresponding to the value of 12+log(O/H) <~7.3, using spectra from the Russian 6m telescope and from the SDSS database. We found two additional blue LSB dwarfs, J0723+3622 and J0852+1351, which appear to be physical companions of J0723+3621 and J0852+1350 situated at the projected distances of ~12--13 kpc. The companion relative velocities, derived from the BTA spectra, are dV = +89 km/s and +30 km/s respectively. The geometry and the relative orientation of orbits and spins in these pairs indicate, respectively, prograde and polar encounters for J0723+3621 and J0852+1350. The NRT HI profiles of J0723+3621 and J0723+3622 indicate a sizable gas flow in this system. The SDSS u,g,r,i images of the five dwarfs are used to derive the photometric parameters and the exponential or Sersic disc model fits. For three of them, the (u-g),(g-r),(r-i) colours of the outer parts, being compared with the PEGASE evolutionary tracks, evidence for the dominance of the old stellar populations with ages of T ~(8-10)+-3 Gyr. For J0723+3622 and J0737+4724, the outer region colours appear rather blue, implying the ages of the oldest visible stars of T <~1-3 Gyr. The new LSB galaxies complement the list of the known most metal-poor and `unevolved' dwarfs in this void, including DDO 68, SDSS J0926+3343 and others. This unique concentration of 'unevolved' dwarf galaxies in a small cell of the nearby Universe implies a physical relationship between the slow galaxy evolution and the void-type global environment.Comment: 16 pages, 5 tables, 9 figures. MNRAS, in pres

The effect of the environment on the HI scaling relations

We use a volume-, magnitude-limited sample of nearby galaxies to investigate the effect of the environment on the HI scaling relations. We confirm that the HI-to-stellar mass ratio anti correlates with stellar mass, stellar mass surface density and NUV-r colour across the whole range of parameters covered by our sample (10^9 <M*<10^11 Msol, 7.5 <mu*<9.5 Msol kpc^-2, 2<NUV-r<6 mag). These scaling relations are also followed by galaxies in the Virgo cluster, although they are significantly offset towards lower gas content. Interestingly, the difference between field and cluster galaxies gradually decreases moving towards massive, bulge-dominated systems. By comparing our data with the predictions of chemo-spectrophotometric models of galaxy evolution, we show that starvation alone cannot explain the low gas content of Virgo spirals and that only ram-pressure stripping is able to reproduce our findings. Finally, motivated by previous studies, we investigate the use of a plane obtained from the relations between the HI-to-stellar mass ratio, stellar mass surface density and NUV-r colour as a proxy for the HI deficiency parameter. We show that the distance from the `HI gas fraction plane' can be used as an alternative estimate for the HI deficiency, but only if carefully calibrated on pre-defined samples of `unperturbed' systems.Comment: Accepted for publication on MNRAS main journal. 11 pages, 6 figures, 1 tabl

Family composition and age at menarche: findings from the international Health Behaviour in School-Aged Children Study

This research was funded by The University of St Andrews and NHS Health Scotland.Background Early menarche has been associated with father absence, stepfather presence and adverse health consequences in later life. This article assesses the association of different family compositions with the age at menarche. Pathways are explored which may explain any association between family characteristics and pubertal timing. Methods Cross-sectional, international data on the age at menarche, family structure and covariates (age, psychosomatic complaints, media consumption, physical activity) were collected from the 2009–2010 Health Behaviour in School-aged Children (HBSC) survey. The sample focuses on 15-year old girls comprising 36,175 individuals across 40 countries in Europe and North America (N = 21,075 for age at menarche). The study examined the association of different family characteristics with age at menarche. Regression and path analyses were applied incorporating multilevel techniques to adjust for the nested nature of data within countries. Results Living with mother (Cohen’s d = .12), father (d = .08), brothers (d = .04) and sisters (d = .06) are independently associated with later age at menarche. Living in a foster home (d = −.16), with ‘someone else’ (d = −.11), stepmother (d = −.10) or stepfather (d = −.06) was associated with earlier menarche. Path models show that up to 89% of these effects can be explained through lifestyle and psychological variables. Conclusions Earlier menarche is reported amongst those with living conditions other than a family consisting of two biological parents. This can partly be explained by girls’ higher Body Mass Index in these families which is a biological determinant of early menarche. Lower physical activity and elevated psychosomatic complaints were also more often found in girls in these family environments.Publisher PDFPeer reviewe

The local star-formation rate density: assessing calibrations using [OII], Ha and UV luminosities

We explore the use of simple star-formation rate (SFR) indicators (such as may be used in high-redshift galaxy surveys) in the local Universe using [OII], Ha, and u-band luminosities from the deeper 275 deg^2 Stripe 82 subsample of the Sloan Digital Sky Survey (SDSS) coupled with UV data from the Galaxy Evolution EXplorer satellite (GALEX). We examine the consistency of such methods using the star-formation rate density (SFRD) as a function of stellar mass in this local volume, and quantify the accuracy of corrections for dust and metallicity on the various indicators. Rest-frame u-band promises to be a particularly good SFR estimator for high redshift studies since it does not require a particularly large or sensitive extinction correction, yet yields results broadly consistent with more observationally expensive methods. We suggest that the [OII]-derived SFR, commonly used at higher redshifts (z~1), can be used to reliably estimate SFRs for ensembles of galaxies, but for high mass galaxies (log(M*/Msun)>10), a larger correction than is typically used is required to compensate for the effects of metallicity dependence and dust extinction. We provide a new empirical mass-dependent correction for the [OII]-SFR.Comment: 22 pages, 16 figures. This version corrects typos in equations 2, 7, and 9 of the published version, as described in the MNRAS Erratum. Published results are unaffected. A simple piece of IDL Code for applying the mass-dependent correction to [OII] SFR available from http://astro.uwaterloo.ca/~dgilbank/data/corroii.pr

The SDSS-III Baryon Oscillation Spectroscopic Survey: Quasar Target Selection for Data Release Nine

The SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), a five-year spectroscopic survey of 10,000 deg^2, achieved first light in late 2009. One of the key goals of BOSS is to measure the signature of baryon acoustic oscillations in the distribution of Ly-alpha absorption from the spectra of a sample of ~150,000 z>2.2 quasars. Along with measuring the angular diameter distance at z\approx2.5, BOSS will provide the first direct measurement of the expansion rate of the Universe at z > 2. One of the biggest challenges in achieving this goal is an efficient target selection algorithm for quasars over 2.2 < z < 3.5, where their colors overlap those of stars. During the first year of the BOSS survey, quasar target selection methods were developed and tested to meet the requirement of delivering at least 15 quasars deg^-2 in this redshift range, out of 40 targets deg^-2. To achieve these surface densities, the magnitude limit of the quasar targets was set at g <= 22.0 or r<=21.85. While detection of the BAO signature in the Ly-alpha absorption in quasar spectra does not require a uniform target selection, many other astrophysical studies do. We therefore defined a uniformly-selected subsample of 20 targets deg^-2, for which the selection efficiency is just over 50%. This "CORE" subsample will be fixed for Years Two through Five of the survey. In this paper we describe the evolution and implementation of the BOSS quasar target selection algorithms during the first two years of BOSS operations. We analyze the spectra obtained during the first year. 11,263 new z>2.2 quasars were spectroscopically confirmed by BOSS. Our current algorithms select an average of 15 z > 2.2 quasars deg^-2 from 40 targets deg^-2 using single-epoch SDSS imaging. Multi-epoch optical data and data at other wavelengths can further improve the efficiency and completeness of BOSS quasar target selection. [Abridged]Comment: 33 pages, 26 figures, 12 tables and a whole bunch of quasars. Submitted to Ap