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Context. Data-driven methods play an increasingly important role in the field of astrophysics. In the context of large spectroscopic surveys of stars, data-driven methods are key in deducing physical parameters for millions of spectra in a short time. Convolutional neural networks (CNNs) enable us to connect observables (e.g. spectra, stellar magnitudes) to physical properties (atmospheric parameters, chemical abundances, or labels in general). Aims. We test whether it is possible to transfer the labels derived from a high-resolution stellar survey to intermediate-resolution spectra of another survey by using a CNN. Methods. We trained a CNN, adopting stellar atmospheric parameters and chemical abundances from APOGEE DR16 (resolution R = 22 500) data as training set labels. As input, we used parts of the intermediate-resolution RAVE DR6 spectra (R ∼ 7500) overlapping with the APOGEE DR16 data as well as broad-band ALL_WISE and 2MASS photometry, together with Gaia DR2 photometry and parallaxes. Results. We derived precise atmospheric parameters Teff, log(g), and [M/H], along with the chemical abundances of [Fe/H], [α/M], [Mg/Fe], [Si/Fe], [Al/Fe], and [Ni/Fe] for 420 165 RAVE spectra. The precision typically amounts to 60 K in Teff, 0.06 in log(g) and 0.02−0.04 dex for individual chemical abundances. Incorporating photometry and astrometry as additional constraints substantially improves the results in terms of the accuracy and precision of the derived labels, as long as we operate in those parts of the parameter space that are well-covered by the training sample. Scientific validation confirms the robustness of the CNN results. We provide a catalogue of CNN-trained atmospheric parameters and abundances along with their uncertainties for 420 165 stars in the RAVE survey. Conclusions. CNN-based methods provide a powerful way to combine spectroscopic, photometric, and astrometric data without the need to apply any priors in the form of stellar evolutionary models. The developed procedure can extend the scientific output of RAVE spectra beyond DR6 to ongoing and planned surveys such as Gaia RVS, 4MOST, and WEAVE. We call on the community to place a particular collective emphasis and on efforts to create unbiased training samples for such future spectroscopic surveys. [ABSTRACT FROM AUTHOR]

Context: The chemical abundances of stars encode information on their place and time of origin. Stars formed together in e.g. a cluster, should present chemical homogeneity. Also disk stars influenced by the effects of the bar and the spiral arms might have distinct chemical signatures depending on the type of orbit that they follow, e.g. from the inner versus outer regions of the Milky Way. Aims: We explore the correlations between velocity and metallicity and the possible distinct chemical signatures of the velocity over-densities of the local Galactic neighbourhood. Methods: We use the large spectroscopic survey RAVE and the Geneva Copenhagen Survey. We compare the metallicity distribution of regions in the velocity plane (vR,vφ) with that of their symmetric counterparts (-vR,vφ). We expect similar metallicity distributions if there are no tracers of a sub-population (e.g. a dispersed cluster, accreted stars), if the disk of the Galaxy is axisymmetric, and if the orbital effects of the bar and the spiral arms are weak. Results: We find that the metallicity-velocity space of the solar neighbourhood is highly patterned. A large fraction of the velocity plane shows differences in the metallicity distribution when comparing symmetric vR regions. The typical differences in the median metallicity are of 0.05 dex with statistical significant of at least 95% confidence, and with values up to 0.6 dex. For stars with low azimuthal velocity vφ, the ones moving outwards. These include stars in the Hercules and Hyades moving groups and other velocity branch-like structures. For higher vφ, the stars moving inwards have higher metallicity than those moving outwards. We have also discovered a positive gradient in vφ with respect to metallicity at high metallicities, apart from the two known positive and negative gradients for the thick and thin disks. Conclusions: The most likely interpretation of the metallicity asymmetry is that it is mainly due to the orbital effects of the Galactic bar and the radial metallicity gradient of the disk. We present a simulation that supports this idea. [ABSTRACT FROM AUTHOR]

Implementation of vegetable and fruit programs in schools is less than optimal. This study aimed to identify, using a theoretical framework, factors associated with implementation of a school vegetable and fruit program; that provides a time in class for children to consume a piece of vegetable or fruit they have brought from home. Three hundred and three randomly selected school principals across the state of New South Wales, Australia responded to a 25-min telephone survey. Principals were asked if their school had implemented a vegetable and fruit program, and which of 12 factors from Damschroder's consolidated framework for implementation research had facilitated or impeded implementation. Multiple logistic regression models examined the association between such factors and program implementation. Seventyeight percent of schools had a vegetable and fruit program. Schools were significantly more likely to implement the program if the principal believed that: the program was effective (OR = 2.97; P < 0.02); they had sufficient resources to implement the program (OR = 4.22; P < 0.0001); the program would not be difficult to implement (OR = 10.16; P < 0.0001) and that the program was as important as other school priorities (OR = 2.45; P < 0.02). Realizing the intended benefits of vegetable and fruit programs requires widespread implementation by schools. Consideration of principal beliefs about the program effectiveness, resources, difficultly and relative importance in program implementation strategies appear key to increasing program implementation. [ABSTRACT FROM AUTHOR]

Multi-object spectrographs have opened a new window on the analyses of the chemo-dynamical properties of old Milky Way stars. These analyses allow us to trace back the internal mechanisms and the external factors that have influenced the evolution of our Galaxy, and therefore understand fundamental aspects of galaxy evolution in general. Here, we present recent results from the RAdial Velocity Experiment (RAVE) and the Gaia-ESO survey. These surveys explore the Milky Way properties in different ways, in terms of sample size and selection, magnitude range, and spectral resolution. We focus here on (i) the first direct detection of evidence for radial migration within the thin disc, providing insight into the history of spiral structure of the Milky Way, and (ii) the chemo-dynamical characterisation of the metal-weak thick and thin discs, for which chemo-dynamical models still have difficulties in reproducing. [ABSTRACT FROM AUTHOR]

We report the identification of extended tidal debris potentially associated with the globular cluster NGC 3201, using the RAdial Velocity Experiment (RAVE) catalogue. We find the debris stars are located at a distance range of 1-7 kpc based on the forthcoming RAVE distance estimates. The derived space velocities and integrals of motion show interesting connections to NGC 3201, modulo uncertainties in the proper motions. Three stars, which are among the four most likely candidates for NGC 3201 tidal debris, are separated by 80° on the sky yet are well matched by the 12 Gyr, [Fe/H] = -1.5 isochrone appropriate for the cluster. This is the first time tidal debris around this cluster has been reported over such a large spatial extent, with implications for the cluster's origin and dynamical evolution. [ABSTRACT FROM AUTHOR]

Despite significant investment in many countries, the extent of schools' adoption of obesity prevention policies and practices has not been widely reported. The aims of this article are to describe Australian schools' adoption of healthy eating and physical activity policies and practices over an 8-year period and to determine if their adoption varies according to schools' size, geographic or socio-economic location. Between 2006 and 2013, a representative randomly selected cohort of primary schools (n = 476) in New South Wales, Australia, participated in four telephone interviews. Repeated measures logistic regression analyses using a Generalised Estimating Equation (GEE) framework were undertaken to assess change over time. The prevalence of all four of the healthy eating practices and one physical activity practice significantly increased, while the prevalence of one physical activity practice significantly decreased. The adoption of practices did not differ by school characteristics. Government investment can equitably enhance school adoption of some obesity prevention policies and practices on a jurisdiction-wide basis. Additional and/or different implementation strategies may be required to facilitate greater adoption of physical activity practices. Ongoing monitoring of school adoption of school policies and practices is needed to ensure the intended benefits of government investment are achieved. [ABSTRACT FROM AUTHOR]

We aim to characterize high-velocity (HiVel) stars in the solar vicinity both chemically and kinematically using the fourth data release of the RAdial Velocity Experiment (RAVE). We used a sample of 57HiVel starswithGalactic rest-frame velocities larger than 275 kms-1 .With 6D position and velocity information, we integrated the orbits of the HiVel stars and found that, on average, they reach out to 13 kpc from the Galactic plane and have relatively eccentric orbits consistent with the Galactic halo. Using the stellar parameters and [α/Fe] estimates from RAVE, we found the metallicity distribution of the HiVel stars peak at [M/H] =-1.2 dex and is chemically consistent with the inner halo. There are a few notable exceptions that include a hypervelocity star candidate, an extremely HiVel bound halo star, and one star that is kinematically consistent with the halo but chemically consistent with the disc. High-resolution spectra were obtained for the metal-rich HiVel star candidate and the second highest velocity star in the sample. Using these high-resolution data, we report the discovery of a metal-rich halo star that has likely been dynamically ejected into the halo from the Galactic thick disc. This discovery could aid in explaining the assembly of the most metal-rich component of the Galactic halo. [ABSTRACT FROM AUTHOR]

Using the RAdial Velocity Experiment fourth data release (RAVE DR4), and a new metallicity calibration that will be also taken into account in the future RAVE DR5, we investigate the existence and the properties of supersolar metallicity stars ([M/H] ≳ +0.1 dex) in the sample, and in particular in the solar neighbourhood. We find that RAVE is rich in supersolar metallicity stars, and that the local metallicity distribution function declines remarkably slowly up to +0.4 dex. Our results show that the kinematics and height distributions of the supersolar metallicity stars are identical to those of the [M/H] ≲ 0 thin-disc giants that we presume were locally manufactured. The eccentricities of the supersolar metallicity stars indicate that half of them are on a roughly circular orbit (e ≤ 0.15), so under the assumption that the metallicity of the interstellar medium at a given radius never decreases with time, they must have increased their angular momenta by scattering at corotation resonances of spiral arms from regions far inside the solar annulus. The likelihood that a star will migrate radially does not seem to decrease significantly with increasing amplitude of vertical oscillations within range of oscillation amplitudes encountered in the disc. [ABSTRACT FROM AUTHOR]

Clinical experience of 50 patients with the CHARGE association is reviewed and problems with management of children born with multiple system involvement is highlighted. It was found that the outlook for survival was poor if more than one of the following three features was present: cyanotic cardiac lesions, bilateral posterior choanal atresia, or tracheo-oesophageal fistula. Mortality was largely due not to the structural heart defects or choanal abnormalities, but reflected underlying pharyngeal and laryngeal incoordination, which resulted in aspiration of secretions. Outcome is likely to be improved if collaboration between specialist surgical teams allows necessary procedures to be performed using the minimum number of anaesthetics. Examination of both the short and long term management of these children has stressed the importance of a multidisciplinary approach to their care. [ABSTRACT FROM AUTHOR]

Transcutaneous Doppler ultrasound represents a convenient, reliable technique for the non-invasive diagnosis and assessment of a rapidly increasing number of diverse circulatory disorders. [ABSTRACT FROM PUBLISHER]

Plasma electrolyte, intermediary metabolite, and hormone concentrations were measured in samples of 110 units of citrate phosphate dextrose blood being used for clinical transfusions. The most important changes from the physiological range were in sodium, potassium, glucose, and lactate concentrations. Mean sodium concentrations fell from 170 mmol/l at the beginning of storage to 156 mmol/l at the end and mean potassium concentrations rose from 7 mmol/l to 25 mmol/l. Glucose had a mean concentration of 20 mmol/l at the beginning of storage and had only fallen to 15 mmol/l at the end. Mean lactate concentrations increased from 7 mmol/l at the beginning of storage to 25 mmol/l at the end. Many samples had cortisol, insulin, and growth hormone concentrations within the physiological range. Citrate phosphate dextrose blood contains a large substrate load that changes during storage and that should be taken into account when infants are transfused large volumes of blood. The strong correlation coefficients with duration of storage for sodium, potassium, and lactate (-0.71, 0.91, and 0.90, respectively) indicate that concentrations of these substrates can be predicted within a narrow range if the duration of blood storage is known. [ABSTRACT FROM AUTHOR]

We use the kinematics of ∼200 000 giant stars that lie within ∼1.5 kpc of the plane to measure the vertical profile of mass density near the Sun. We find that the dark mass contained within the isodensity surface of the dark halo that passes through the Sun ((6 ± 0.9) × 1010 M⊙), and the surface density within 0.9 kpc of the plane ((69 ± 10) M⊙ pc−2) are almost independent of the (oblate) halo's axis ratio q. If the halo is spherical, 46 per cent of the radial force on the Sun is provided by baryons, and only 4.3 per cent of the Galaxy's mass is baryonic. If the halo is flattened, the baryons contribute even less strongly to the local radial force and to the Galaxy's mass. The dark matter density at the location of the Sun is 0.0126 q−0.89 M⊙ pc−3 = 0.48 q−0.89 GeV cm−3. When combined with other literature results we find hints for a mildly oblate dark halo with q ≃ 0.8. Our value for the dark mass within the solar radius is larger than that predicted by cosmological dark-matter-only simulations but in good agreement with simulations once the effects of baryonic infall are taken into account. Our mass models consist of three double-exponential discs, an oblate bulge and a Navarro–Frenk–White dark matter halo, and we model the dynamics of the RAVE (RAdial Velocity Experiment) stars in the corresponding gravitational fields by finding distribution functions f J that depend on three action integrals. Statistical errors are completely swamped by systematic uncertainties, the most important of which are the distance to the stars in the photometric and spectroscopic samples and the solar distance to the Galactic Centre. Systematics other than the flattening of the dark halo yield overall uncertainties ∼15 per cent. [ABSTRACT FROM AUTHOR]

We determine the Galactic potential in the solar neigbourhood from RAVE observations.We select red clump stars for which accurate distances, radial velocities, and metallicities have been measured. Combined with data from the 2MASS and UCAC catalogues, we build a sample of ~4600 red clump stars within a cylinder of 500 pc radius oriented in the direction of the South Galactic Pole, in the range of 200 pc to 2000 pc distances. We deduce the vertical force and the total mass density distribution up to 2 kpc away from the Galactic plane by fitting a distribution function depending explicitly on three isolating integrals of the motion in a separable potential locally representing the Galactic one with four free parameters. Because of the deep extension of our sample, we can determine nearly independently the dark matter mass density and the baryonic disc surface mass density. We find (i) at 1 kpc Kz=(2πG) = 68:5 ± 1:0 M☉ pc-2; and (ii) at 2 kpc Kz=(2πG) = 96:9 ± 2:2 M☉ pc-2. Assuming the solar Galactic radius at R0 = 8:5 kpc, we deduce the local dark matter density ρDM(z = 0) = 0:0143 ± 0:0011 M☉ pc-3 = 0:542± 0:042 Gev cm-3 and the baryonic surface mass density Σbar = 44:4 ± 4:1 M☉ pc-2. Our results are in agreement with previously published Kz determinations up to 1 kpc, while the extension to 2 kpc shows some evidence for an unexpectedly large amount of dark matter. A flattening of the dark halo of order 0.8 can produce such a high local density in combination with a circular velocity of 240 km s-1. It could also be consistent with a spherical cored dark matter profile whose density does not drop sharply with radius. Another explanation, allowing for a lower circular velocity, could be the presence of a secondary dark component, a very thick disc resulting either from the deposit of dark matter from the accretion of multiple small dwarf galaxies, or from the presence of an effective "phantom" thick disc in the context of effective galactic-scale modifications of gravity. [ABSTRACT FROM AUTHOR]

We examine the star formation in the outer halo of NGC 1275, the central galaxy in the Perseus cluster (Abell 426), using far-ultraviolet and optical images obtained with the Hubble Space Telescope. We have identified a population of very young, compact star clusters with typical ages of a few Myr. The star clusters are organized on multiple kiloparsec scales. Many of these star clusters are associated with ‘streaks’ of young stars, the combination of which has a cometary appearance. We perform photometry on the star clusters and diffuse stellar streaks, and fit their spectral energy distributions to obtain ages and masses. These young stellar populations appear to be normal in terms of their masses, luminosities and cluster formation efficiency; <10 per cent of the young stellar mass is located in star clusters. Our data suggest star formation is associated with the evolution of some of the giant gas filaments in NGC 1275 that become gravitationally unstable on reaching and possibly stalling in the outer galaxy. The stellar streaks then could represent stars moving on ballistic orbits in the potential well of the galaxy cluster. We propose a model where star-forming filaments, switched on ∼50 Myr ago and are currently feeding the growth of the NGC 1275 stellar halo at a rate of ≈−2 to 3 M⊙ yr−1. This type of process may also build stellar haloes and form isolated star clusters in the outskirts of youthful galaxies. [ABSTRACT FROM PUBLISHER]

Aims. The nature of the thick disc and its relation to the thin disc is presently an important subject of debate. In fact, the structural and chemodynamical transition between disc populations can be used as a test of the proposed models of Galactic disc formation and evolution. Methods. We used the atmospheric parameters, [α/Fe] abundances, and radial velocities, which were determined from the Gaia-ESO Survey GIRAFFE spectra of FGK-type stars (first nine months of observations) to provide a chemo-kinematical characterisation of the disc stellar populations. We focussed on a subsample of 1016 stars with high-quality parameters, covering the volume ∣Z∣ < 4.5 kpc and R in the range 2-13 kpc. Results. We have identified a thin to thick disc separation in the [α/Fe] vs. [M/H] plane, thanks to the presence of a low-density region in the number density distribution. The thick disc stars seem to lie in progressively thinner layers above the Galactic plane, as metallicity increases and [α/Fe] decreases. In contrast, the thin disc population presents a constant value of the mean distance to the Galactic plane at all metallicities. In addition, our data confirm the already known correlations between Vϕ and [M/H] for the two discs. For the thick disc sequence, a study of the possible contamination by thin disc stars suggests a gradient up to 64 ± 9 km s-1 dex-1. The distributions of azimuthal velocity, vertical velocity, and orbital parameters are also analysed for the chemically separated samples. Concerning the gradients with galactocentric radius, we find, for the thin disc, a flat behaviour of the azimuthal velocity, a metallicity gradient equal to -0.058 ± 0.008 dex kpc-1 and a very small positive [α/Fe] gradient. For the thick disc, flat gradients in [M/H] and [α/Fe] are derived. Conclusions. Our chemo-kinematical analysis suggests a picture where the thick disc seems to have experienced a settling process, during which its rotation increased progressively and, possibly, the azimuthal velocity dispersion decreased. At [M/H] ≈ -0.25 dex and [α/Fe] ≈ 0.1 dex, the mean characteristics of the thick disc in vertical distance to the Galactic plane, rotation, rotational dispersion, and stellar orbits' eccentricity agree with that of the thin disc stars of the same metallicity, suggesting a possible connection between these two populations at a certain epoch of the disc evolution. Finally, the results presented here, based only on the first months of the Gaia ESO Survey observations, confirm how crucial large high-resolution spectroscopic surveys outside the solar neighbourhood are today for our understanding of the Milky Way history. [ABSTRACT FROM AUTHOR]

Diffuse interstellar bands (DIBs) are usually observed in spectra of hot stars, where interstellar lines are rarely blended with stellar ones. The need for hot stars is a strong limitation in the number of sightlines we can observe and their distribution in the Galaxy, as hot stars are rare and concentrated in the Galactic plane. We are introducing a new method, where interstellar lines can be observed in spectra of cool stars in large spectroscopic surveys. The method is completely automated and does not require prior knowledge of the stellar parameters. The main step is a construction of the stellar spectrum, which is done by finding other observed spectra that lack interstellar features and are otherwise very similar to the spectrum in question. Such spectra are then combined into a single stellar spectrum template, matching the stellar component of the observed spectrum. We demonstrate the performance of this new method on a sample of 482,430 Radial Velocity Experiment survey spectra. However, many spectra have to be combined (48 on average) in order to achieve a signal-to-noise ratio high enough to measure the profile of the DIB at 8620 Å, hence limiting the spatial information about the interstellar medium. We compare its equivalent width with extinction maps and with Bayesian reddening, calculated for individual stars, and provide a linear relation between the equivalent width and reddening. Separately from the introduced method, we calculate equivalent widths of the DIB in spectra of hot stars with known extinction and compare all three linear relations. [ABSTRACT FROM AUTHOR]

RAVE, the unbiased magnitude limited survey of southern sky stars, contained 456,676 medium-resolution spectra at the time of our analysis. Spectra cover the Ca II infrared triplet (IRT) range, which is a known indicator of chromospheric activity. Our previous work classified all spectra using locally linear embedding. It identified 53,347 cases with a suggested emission component in calcium lines. Here, we use a spectral subtraction technique to measure the properties of this emission. Synthetic templates are replaced by the observed spectra of non-active stars to bypass the difficult computations of non-local thermal equilibrium profiles of the line cores and stellar parameter dependence. We derive both the equivalent width of the excess emission for each calcium line on a 5 Å wide interval and their sum EWIRT for ∼44,000 candidate active dwarf stars with signal-to-noise ratio >20, with no cuts on the basis of the source of their emission flux. From these, ∼14,000 show a detectable chromospheric flux with at least a 2σ confidence level. Our set of active stars vastly enlarges previously known samples. Atmospheric parameters and, in some cases, radial velocities of active stars derived from automatic pipelines suffer from systematic shifts due to their shallower calcium lines. We re-estimate the effective temperature, metallicity, and radial velocities for candidate active stars. The overall distribution of activity levels shows a bimodal shape, with the first peak coinciding with non-active stars and the second with the pre-main-sequence cases. The catalog will be made publicly available with the next RAVE public data releases. [ABSTRACT FROM AUTHOR]

ABSTRACT We analyse the kinematics of disc stars observed by the RAdial Velocity Experiment (RAVE) survey in and beyond the solar neighbourhood. We detect significant overdensities in the velocity distributions using a technique based on the wavelet transform. We find that the main local kinematic groups are large-scale features, surviving at least up to ∼1 kpc from the Sun in the direction of antirotation, and also at below the Galactic plane. We also find that for regions located at different radii than the Sun, the known groups appear shifted in the v R- vφ velocity plane. For example, the Hercules group has a larger azimuthal velocity for regions inside the solar circle and a lower value outside. We have also discovered a new group at in the solar neighbourhood and confirmed the significance of other previously found groups. Some of these trends detected for the first time are consistent with dynamical models of the effects of the bar and the spiral arms. More modelling is required to definitively characterize the non-axisymmetric components of our Galaxy using these groups. [ABSTRACT FROM AUTHOR]

The structure of the Sagittarius stream in the southern Galactic hemisphere is analyzed with the Sloan Digital Sky Survey Data Release 8. Parallel to the Sagittarius tidal track, but ~10° away, there is another fainter and more metal-poor stream. We provide evidence that the two streams follow similar distance gradients but have distinct morphological properties and stellar populations. The brighter stream is broader, contains more metal-rich stars, and has a richer color-magnitude diagram with multiple turnoffs and a prominent red clump as compared to the fainter stream. Based on the structural properties and the stellar population mix, the stream configuration is similar to the Northern "bifurcation." In the region of the South Galactic Cap, there is overlapping tidal debris from the Cetus stream, which crosses the Sagittarius stream. Using both photometric and spectroscopic data, we show that the blue straggler population belongs mainly to Sagittarius and the blue horizontal branch stars belong mainly to the Cetus stream in this confused location in the halo. [ABSTRACT FROM AUTHOR]

We develop, implement, and characterize an enhanced data reduction approach which delivers precise, accurate, radial velocities from moderate resolution spectroscopy with the fiber- fed VLT/FLAMES+GIRAFFE facility. This facility, with appropriate care, delivers radial velocities adequate to resolve the intrinsic velocity dispersions of the very faint dwarf spheroidal (dSph) galaxies. Importantly, repeated measurements let us reliably calibrate our individual velocity errors (0.2 kms-1 ≼ δv 5 km s-1) and directly detect stars with variable radial velocities. We show, by application to the Bootes I dSph, that the intrinsic velocity dispersion of this system is significantly below 6.5 km s s-1) reported by previous studies. Our data favor a two-population model of Bootes I, consisting of a majority "cold" stellar component, with velocity dispersion Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. s s-1), and a minority "hot" stellar component, with velocity dispersion ~9 km s-1, although we cannot completely rule out a single component distribution with velocity dispersion Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. We speculate that this complex velocity distribution actually reflects the distribution of velocity anisotropy in Bootes I, which is a measure of its formation processes. [ABSTRACT FROM AUTHOR]

A spectroscopic survey of nearly 700 stars probing the Galactic Thick Disc far from the Solar neighbourhood is performed. The MATISSE (MATrix Inversion for Spectral SynthEsis) algorithm is developed and trained in order to automatically obtain atmospheric parameters of stars. The derived effective temperatures, surface gravities and overall metallicities are then combined to stellar evolution isochrones, radial velocities and proper motions to derive the distances, kinematics and orbital parameters of the sample stars. Results are compared with simulations from the Besançon model of the Milky Way. [ABSTRACT FROM AUTHOR]

We apply the optimal filter technique to Sloan Digital Sky Survey photometry around Segue 1 and find that the outer parts of the cluster are distorted. There is strong evidence for elongations of extra-tidal stars, extending both eastwards and southwestwards of the cluster. The extensions have similar differential Hess diagrams to Segue 1. A Kolmogorov–Smirnov test suggests a high probability that both come from the same parent distribution. The location of Segue 1 is close to crossings of the tidal wraps of the Sagittarius stream. By extracting blue horizontal branch stars from Sloan's spectral data base, two kinematic features are isolated and identified with different wraps of the Sagittarius stream. We show that Segue 1 is moving with a velocity that is close to one of the wraps. At this location, we estimate that there are enough Sagittarius stars, indistinguishable from Segue 1 stars, to inflate the velocity dispersion and hence the mass-to-light ratio. All the available evidence is consistent with the interpretation that Segue 1 is a star cluster, originally from the Sagittarius galaxy, and now dissolving in the Milky Way. [ABSTRACT FROM AUTHOR]

We confirm and extend the recent finding that the central surface density of galaxy dark matter haloes, where r0 and are the halo core radius and central density, is nearly constant and independent of galaxy luminosity. Based on the co-added rotation curves (RCs) of ∼1000 spiral galaxies, the mass models of individual dwarf irregular and spiral galaxies of late and early types with high-quality RCs, and the galaxy–galaxy weak-lensing signals from a sample of spiral and elliptical galaxies, we find that in units of . We also show that the observed kinematics of Local Group dwarf spheroidal galaxies are consistent with this value. Our results are obtained for galactic systems spanning over 14 mag, belonging to different Hubble types and whose mass profiles have been determined by several independent methods. In the same objects, the approximate constancy of is in sharp contrast to the systematical variations, by several orders of magnitude, of galaxy properties, including and central stellar surface density. [ABSTRACT FROM AUTHOR]

We present a measure of the inclination of the velocity ellipsoid at 1 kpc below the Galactic plane using a sample of red clump giants from the RAdial Velocity Experiment (RAVE) Data Release 2. We find that the velocity ellipsoid is tilted towards the Galactic plane with an inclination of . We compare this value to computed inclinations for two mass models of the Milky Way. We find that our measurement is consistent with a short scalelength of the stellar disc if the dark halo is oblate or with a long scalelength if the dark halo is prolate. Once combined with independent constraints on the flattening of the halo, our measurement suggests that the scalelength is approximately halfway between these two extreme values, with a preferred range 2.5–2.7 kpc for a nearly spherical halo. Nevertheless, no model can be clearly ruled out. With the continuation of the RAVE survey, it will be possible to provide a strong constraint on the mass distribution of the Milky Way using refined measurements of the orientation of the velocity ellipsoid. [ABSTRACT FROM AUTHOR]

We have searched for in-falling stellar streams on to the local Milky Way disc in the CORrelation RAdial VELocities (CORAVEL) and RAdial Velocity Experiment (RAVE) surveys. The CORAVEL survey consists of local dwarf stars (Nördstrom et al. Geneva–Copenhagen survey) and local Famaey et al. giant stars. We select RAVE stars with radial velocities that are sensitive to the Galactic vertical space velocity (Galactic latitude b < −45°). Kuiper statistics have been employed to test the symmetry of the Galactic vertical velocity distribution functions in these samples for evidence of a net vertical flow that could be associated with a (tidal?) stream of stars with vertically coherent kinematics. In contrast to the ‘Field of Streams’ found in the outer halo, we find that the local volumes of the solar neighbourhood sampled by the CORAVEL dwarfs (complete within ∼3 × 10−4 kpc3), CORAVEL giants (complete within ∼5 × 10−2 kpc3) and RAVE (5–15 per cent complete within ∼8 kpc3) are devoid of any vertically coherent streams containing hundreds of stars. This is sufficiently sensitive to allow our RAVE sample to rule out the passing of the tidal stream of the disrupting Sagittarius (Sgr) dwarf galaxy through the solar neighbourhood. This agrees with the most-recent determinations of its orbit and dissociates it from the Helmi et al. halo stream. Our constraints on the absence of the Sgr stream near the Sun could prove a useful tool for discriminating between Galactic potential models. The lack of a net vertical flow through the solar neighbourhood in the CORAVEL giants and RAVE samples argues against the Virgo overdensity crossing the disc near the Sun. There are no vertical streams in the CORAVEL giants and RAVE samples with stellar densities ≳1.6 × 104 and 1.5 × 103 stars kpc−3, respectively, and therefore no evidence for locally enhanced dark matter. [ABSTRACT FROM AUTHOR]

The advent of next-generation telescopes with very wide fields-of-view creates a need for deep and precise reference frames for astrometric calibrations. The Deep Astrometric Standards (DAS) program is designed to establish such a frame, by providing absolute astrometry at the 5–10 mas level in four 10 deg2 Galactic fields, to a depth of V=25. The source of our basic reference frame is the UCAC2 catalog, significantly improved by additional observations, and new VLBI positions of radio-loud and optically visible QSOs. We describe all the major steps in the construction of the DAS fields and provide the current status of this project. [ABSTRACT FROM PUBLISHER]

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CHARGE association includes patients with at least four features prefixed by the letters of the mnemonic: Coloboma, Heart defects, Atresia of the choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies and/or hearing loss. Many also have facial palsy. We report a series identified by collaboration within one centre of all specialties concerned in the management of the CHARGE association. Ocular abnormalities were found in 44 out of 50 patients with the CHARGE association. Of these, 41 had 'typical' colobomata. The majority had retinochoroidal colobomata with optic nerve involvement, but only 13 patients had an iris defect. Two patients had atypical iris colobomata with normal fundi. Additional features were microphthalmos in 21 patients, optic nerve hypoplasia in four, nystagmus in 12, and a vertical disorder of eye movement in four of the 22 cases with facial palsy. We report an incidence of coloboma in the CHARGE association of 86% (43/50) compared with a previous cumulative reported incidence of 66% (112/170). We believe that there may have been previous underdiagnosis of colobomata in children with multiple congenital abnormalities. [ABSTRACT FROM PUBLISHER]

The roles of posterior bulging of the interventricular septum (septal bulge) and of systolic septal mitral apposition in patients with simple transposition of the great arteries are not known. Cross sectional echocardiograms of 40 such patients were reviewed (after exclusion of those with fixed left ventricular outflow tract obstruction) and haemodynamic findings were compared with long and short axis measurements within the left ventricle. There was no significant correlation between the degree of septal bulge and systolic gradient across the left ventricular outflow tract, but septal bulge correlated weakly with systolic right ventricular pressure and inversely with pulmonary arteriolar resistance index. Systolic left ventricular outflow gradient was inversely related to the minimum systolic distance between the anterior mitral leaflet and interventricular septum. No patients without complete systolic apposition of the anterior mitral leaflet and interventricular septum had a left ventricular outflow gradient greater than 20 mm Hg. Conversely, even when cross sectional echocardiography showed apparently total obstruction of the left ventricular outflow tract at some time in systole there was often no significant gradient detected during haemodynamic study. In the short axis cuts closeness of the papillary muscles to the interventricular septum or to each other was unrelated to systolic gradient. This study shows that (a) cross sectional echocardiography can identify fixed obstruction of the left ventricular outflow tract in simple transposition of the great arteries; (b) the degree of septal bulge, unless complicated by fibrous thickening of the anterior mitral leaflet and interventricular septum, is unrelated to the gradient across the left ventricular outflow tract; (c) the absence of systolic septal/mitral apposition excludes a significant gradient at that site across the left ventricular outflow tract; and (d) papillary muscle geometry is unrelated to dynamic gradients across the left ventricular outflow in this condition. [ABSTRACT FROM PUBLISHER]

Precise non-invasive localisation of the site of a small ventricular septal defect was attempted using a new technique that simultaneously combines conventional cross sectional echocardiography with a Doppler system by superimposing the colour coded direction and velocity of blood flow directly on to real time ultrasound images. Twenty three patients with unoperated ventricular septal defects and a further eight after surgical closure were studied; 12 children with normal hearts served as controls. A colour coded blood flow jet entering the right ventricle during systole was identified in all 23 unoperated patients, in 11 of whom the defect was too small to be visualised by conventional cross sectional echocardiography. The colour Doppler technique precisely located 19 perimembranous and five trabecular defects (one patient had two defects). Five of the postoperative patients were without clinical evidence of a significant shunt but had pansystolic murmurs. In each of these five, trans-septal shunt blood flow as demonstrated by colour Doppler images whereas in only three of these patients was the residual defect large enough to be visualised by conventional cross sectional echocardiography. Three postoperative patients had no murmurs and showed no residual shunt on colour Doppler images. This was confirmed at cardiac catheterisation. There were no false positive results among the controls. This technique is useful for the more accurate diagnosis and location of ventricular septal defects and may help in assessing their natural or surgical closure. [ABSTRACT FROM PUBLISHER]

If cross sectional echocardiography in isolation is used to diagnose critical left ventricular outflow obstruction in neonates, false positive and false negative diagnoses may result. Continuous wave Doppler velocimetry was used to measure blood flow velocity in the ascending and descending thoracic aorta in six neonates (aged less than 6 weeks) presenting with reduced or absent peripheral pulses in order to determine the important sites of obstruction. This technique demonstrated abnormal high velocity blood flow jets (three times higher than normal) in the ascending aorta in three patients with normal descending aortic flow velocity, suggesting aortic stenosis. In the other three patients velocity in the ascending aorta was normal but high in the descending aorta, suggesting coarctation. The Doppler diagnosis was confirmed in the five patients who required surgery. Two patients had residual high velocity jets after aortic valvotomy. Both had significant pressure gradients across the aortic valve at cardiac catheterisation with good agreement between actual gradients and those predicted by the Doppler technique. Thus a combined anatomical and physiological approach using cross sectional echocardiography and continuous wave Doppler velocimetry enables accurate non-invasive definition of the site of left ventricular outflow obstruction and may obviate the need for invasive investigation in these sick neonates. [ABSTRACT FROM PUBLISHER]

Peak ascending and descending aortic blood flow velocities were measured using continuous wave Doppler ultrasound velocimetry in 30 children with coarctation or recoarctation of the aorta and in 13 control subjects. The results were compared with the arm to leg systolic blood pressure difference. The peak flow velocities in the descending aorta were significantly higher in the patients than in the control subjects and there was a close correlation with the systolic blood pressure gradient. Since there was no overlap of flow velocities between the patients and the control subjects the Doppler technique enables coarctation confidently to be excluded as well as demonstrating its presence and severity. The method is simple, rapid, independent of the condition of the aortic valve, and is applicable to neonates in whom the diagnosis of coarctation may otherwise be difficult. In older children it is useful for detecting recoarctation and following its progress, particularly in patients in whom a reliable estimate of the systolic blood pressure gradient cannot be obtained. [ABSTRACT FROM PUBLISHER]

The dominance of Mustard's operation for transposition of the great arteries has been challenged by the recent revival of Senning's repair because it promises better long-term results in terms of venous obstruction and atrial haemodynamics. These hypotheses were tested by recording jugular venous flow waveforms transcutaneously in 24 postoperative patients with simple complete transposition using a bidirectional Doppler blood velocimeter. Eight patients had undergone Mustard's operation and 16 the Senning alternative; all had previously had a postoperative cardiac catheterisation. Both groups of patients had similar left ventricular, pulmonary arterial, and systemic venous atrial pressures. No child showed any evidence at catheterisation of either mitral regurgitation or of superior vena caval pathway obstruction. These two findings were endorsed by the transcutaneous Doppler recordings. Jugular venous flow in normal children exhibits two maxima, one of atrial filling during ventricular systole, the other of ventricular filling occurs once the tricuspid valve has opened. Both operative procedures diminished the size of the former phase, but the Mustard did so more. After Mustard's operation forward flow during the atrial filling phase was absent in approximately half the cardiac cycles recorded, and severely diminished in the rest. By contrast, there was approximately a 90 per cent appearance of atrial filling waves after Senning's operation which also provided significantly better atrial function than Mustard's procedure in terms of peak velocity of blood entering the atrium and total atrial filling. It is therefore concluded that both procedures compromise atrial volume and compliance but Senning's repair to a much lesser extent. [ABSTRACT FROM PUBLISHER]

Material from hearts known to have had recent myocardial infarction and biopsies of dog hearts subjected to an experimental procedure producing ischaemic injury, were examined by polarising microscopy. A technique which depends on the relaxation of sarcomeres on ischaemic areas of myocardia was used and assessed for its value in the diagnosis of early myocardial infarction. We found no statistically significant difference in sarcomere lengths in ischaemic and control heart muscle in man. The dog study failed to show changes with a study period of up to 2 h after ligation. We do not support the suggestion that sarcomere length is a useful measurement in the demonstration of early myocardial ischaemic injury in man. [ABSTRACT FROM AUTHOR]

Seven hundred and twenty three biopsies were obtained from 20 dogs after coronary artery ligation for 5, 30, 45, 60 or 120 min (n=4 dogs for each group). Paired values for blood flow (radioactive microspheres) and tissue ATP content were obtained for each biopsy and related to the duration of ischaemia. Three states of ischaemic injury could be recognised. In the first, designated as "tolerable" ischaemia, coronary flow was reduced by up to 50%. In this flow band, ATP depletion was relatively small and time-independent. If flow was reduced by 60 to 80%, a state of "critical" ischaemia was identified where ATP depletion was both flow- and time-dependent and, in this relatively narrow range, small changes in flow or duration could result in major changes in ATP depletion. With severe flow reductions of greater than 80%, designated as "lethal" ischaemia, a complex pattern emerged such that with up to 30 min of ischaemia, ATP fell progressively with increasing time and flow deprivation. Between 30 and 45 min ATP depletion accelerated and beyond 45 min the time-dependency disappeared with tissue ATP content remaining relatively constant at a severely depressed level for several hours.All of these results are discussed in the light of earlier proposals (disputed) that tissue injury as expressed by ATP depletion can be predicted by the product of ischaemic duration and flow deprivation. [ABSTRACT FROM PUBLISHER]

Following pulmonary arterial constriction, 22 pigs developed right ventricular failure and 10 right ventricular hypertrophy. Comparing results with those obtained in 21 normal pigs (no pulmonary artery constriction), it was found the right ventricular peak systolic and end-diastolic pressures, cardiac output, and right ventricular weight distinguished hypertrophied and failing hearts from normal ones. Cardiac output was lower in failing hearts than in hypertrophied hearts and was the only variable which significantly differentiated between these two groups. Left ventricular pressures and left ventricular and right ventricular dP/dtmax, and maximum [(dP/dt) / P] did not distinguish failing from hypertrophied hearts. Left ventricular pressure, maximum [(dP/dt) / P] and left ventricular and right ventricular dP/dtmax were not significantly different in the three groups. [ABSTRACT FROM PUBLISHER]

A method is described whereby lignocaine can be measured in small samples of canine myocardium. A proteolytic enzyme is used to digest the tissue, and the drug, together with an internal standard, is subsequently extracted into an organic solvent and measured by gas-liquid chromatography. The method is reproducible using tissue samples as small as 50 mg and appears to be suitable for the measurement of a number of drugs in small samples of tissue. [ABSTRACT FROM PUBLISHER]

OBJECTIVE--To study the incidence, predisposing factors, and clinical significance of arrhythmias early and late after the Fontan operation for congenital heart disease. PATIENTS AND METHODS--All 104 consecutive patients undergoing Fontan repair from 1975 to 1988 were studied retrospectively. Hospital records were reviewed for perioperative arrhythmia. Clinical information and annual electrocardiograms were available for all 78 hospital survivors during a follow up of up to 13 years (mean 3.7 years). Ambulatory electrocardiographic monitoring was performed in 67 patients (81%). RESULTS--Eleven patients (10.6%) developed a perioperative tachycardia (eight, atrial flutter; three, His bundle tachycardia). Multivariate analysis showed that raised preoperative mean pulmonary artery pressure and low aortic saturation were significant risk factors for the development of atrial flutter (r2 = 0.32, p = 0.0001) but not for His bundle tachycardia. Despite intensive medical treatment 10 of these 11 patients died. At the last visit 72 (92%) of the 78 patients were in sinus rhythm on their standard 12 lead electrocardiogram. Junctional rhythm was present in three patients, two patients had atrial flutter, and one had a paced rhythm. Ambulatory monitoring did not show important bradycardia or ventricular arrhythmias. Actuarial survival free of supraventricular arrhythmia was 82% at eight years after operation. Multivariate analysis identified older age, increased right atrial size, and raised mean preoperative pulmonary artery pressure as risk factors for arrhythmia during intermediate follow-up (r2 = 0.46, p less than 0.001). Late tachycardias, in contrast to those occurring in the perioperative period, were not associated with an increased mortality. CONCLUSIONS--Except for his bundle tachycardia in the perioperative period, early and late arrhythmias after a Fontan operation seem to be a consequence of adverse preoperative and postoperative haemodynamic function. The perioperative outcome is therefore poor even when the patient can be restored to sinus rhythm. Medical and surgical modifications to improve the haemodynamic disturbances associated with arrhythmias are therefore indicated. [ABSTRACT FROM PUBLISHER]