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We report the discovery of two mini-Neptunes in near 2:1 resonance orbits (P = 7.610303 d for HIP 113103 b and P  = 14.245651 d for HIP 113103 c) around the adolescent K-star HIP 113103 (TIC 121490076). The planet system was first identified from the TESS mission, and was confirmed via additional photometric and spectroscopic observations, including a ∼17.5 h observation for the transits of both planets using ESA CHEOPS. We place ≤4.5 min and ≤2.5 min limits on the absence of transit timing variations over the 3 yr photometric baseline, allowing further constraints on the orbital eccentricities of the system beyond that available from the photometric transit duration alone. With a planetary radius of R p  =   |$1.829_{-0.067}^{+0.096}$| R⊕, HIP 113103 b resides within the radius gap, and this might provide invaluable information on the formation disparities between super-Earths and mini-Neptunes. Given the larger radius R p  =  |$2.40_{-0.08}^{+0.10}$| R⊕ for HIP 113103 c, and close proximity of both planets to HIP 113103, it is likely that HIP 113103 b might have lost (or is still losing) its primordial atmosphere. We therefore present simulated atmospheric transmission spectra of both planets using JWST, HST , and Twinkle. It demonstrates a potential metallicity difference (due to differences in their evolution) would be a challenge to detect if the atmospheres are in chemical equilibrium. As one of the brightest multi sub-Neptune planet systems suitable for atmosphere follow up, HIP 113103 b and HIP 113103 c could provide insight on planetary evolution for the sub-Neptune K-star population. [ABSTRACT FROM AUTHOR]

In this paper, we present observations of two high-resolution transit data sets obtained with ESPRESSO of the bloated sub-Saturn planet WASP-131 b. We have simultaneous photometric observations with NGTS and EulerCam. In addition, we utilized photometric light curves from TESS , WASP, EulerCam, and TRAPPIST of multiple transits to fit for the planetary parameters and update the ephemeris. We spatially resolve the stellar surface of WASP-131 utilizing the Reloaded Rossiter McLaughlin technique to search for centre-to-limb convective variations, stellar differential rotation, and to determine the star–planet obliquity for the first time. We find WASP-131 is misaligned on a nearly retrograde orbit with a projected obliquity of |$\lambda = 162.4\substack{+1.3 \\ -1.2}^{\circ }$|. In addition, we determined a stellar differential rotation shear of α = 0.61 ± 0.06 and disentangled the stellar inclination (⁠|$i_* = 40.9\substack{+13.3 \\ -8.5}^{\circ }$|) from the projected rotational velocity, resulting in an equatorial velocity of |$v_{\rm {eq}} = 7.7\substack{+1.5 \\ -1.3}$| km s−1. In turn, we determined the true 3D obliquity of |$\psi = 123.7\substack{+12.8 \\ -8.0}^{\circ }$| , meaning the planet is on a perpendicular/polar orbit. Therefore, we explored possible mechanisms for the planetary system's formation and evolution. Finally, we searched for centre-to-limb convective variations where there was a null detection, indicating that centre-to-limb convective variations are not prominent in this star or are hidden within red noise. [ABSTRACT FROM AUTHOR]

Transiting exoplanets orbiting young nearby stars are ideal laboratories for testing theories of planet formation and evolution. However, to date only a handful of stars with age <1 Gyr have been found to host transiting exoplanets. Here we present the discovery and validation of a sub-Neptune around HD 18599 , a young (300 Myr), nearby (d  = 40 pc) K star. We validate the transiting planet candidate as a bona fide planet using data from the TESS  , Spitzer  , and Gaia  missions, ground-based photometry from IRSF  , LCO  , PEST  , and NGTS  , speckle imaging from Gemini, and spectroscopy from CHIRON  , NRES  , FEROS  , and Minerva -Australis . The planet has an orbital period of 4.13 d , and a radius of 2.7 R ⊕ . The RV data yields a 3-σ mass upper limit of 30.5 M ⊕  which is explained by either a massive companion or the large observed jitter typical for a young star. The brightness of the host star (V ∼9 mag) makes it conducive to detailed characterization via Doppler mass measurement which will provide a rare view into the interior structure of young planets. [ABSTRACT FROM AUTHOR]

Why aren't students signing up to study geophysics? Are they unaware of how in-demand it is? Or are they just too cool for geophysics school? [ABSTRACT FROM AUTHOR]

We report on the discovery and validation of a two-planet system around a bright (V  = 8.85 mag) early G dwarf (1.43  R⊙, 1.15  M⊙, TOI 2319) using data from NASA's Transiting Exoplanet Survey Satellite (TESS). Three transit events from two planets were detected by citizen scientists in the month-long TESS light curve (sector 25), as part of the Planet Hunters TESS project. Modelling of the transits yields an orbital period of |$11.6264 _{ - 0.0025 } ^ { + 0.0022 }$|  d and radius of |$3.41 _{ - 0.12 } ^ { + 0.14 }$|  R⊕ for the inner planet, and a period in the range 19.26–35 d and a radius of |$5.83 _{ - 0.14 } ^ { + 0.14 }$|  R⊕ for the outer planet, which was only seen to transit once. Each signal was independently statistically validated, taking into consideration the TESS light curve as well as the ground-based spectroscopic follow-up observations. Radial velocities from HARPS-N and EXPRES yield a tentative detection of planet b, whose mass we estimate to be |$11.56 _{ - 6.14 } ^ { + 6.58 }$|  M⊕, and allow us to place an upper limit of 27.5 M⊕ (99 per cent confidence) on the mass of planet c. Due to the brightness of the host star and the strong likelihood of an extended H/He atmosphere on both planets, this system offers excellent prospects for atmospheric characterization and comparative planetology. [ABSTRACT FROM AUTHOR]

Background: Previous studies have suggested that finite element analysis (FEA) can estimate the rupture risk of an abdominal aortic aneurysm (AAA); however, the value of biomechanical estimates over measurement of AAA diameter alone remains unclear. This study aimed to compare peak wall stress (PWS) and peak wall rupture index (PWRI) in participants with ruptured and asymptomatic intact AAAs. Methods: The reproducibility of semiautomated methods for estimating aortic PWS and PWRI from CT images was assessed. PWS and PWRI were estimated in people with ruptured AAAs and those with asymptomatic intact AAAs matched by orthogonal diameter on a 1: 2 basis. Spearman's correlation coefficient was used to assess the association between PWS or PWRI and AAA diameter. Independent associations between PWS or PWRI and AAA rupture were identified by means of logistic regression analyses. Results: Twenty individuals were included in the analysis of reproducibility. The main analysis included 50 patients with an intact AAA and 25 with a ruptured AAA. Median orthogonal diameter was similar in ruptured and intact AAAs (82·3 (i.q.r. 73·5-92·0) versus 81·0 (73·2-92·4)mm respectively; P= 0·906). Median PWS values were 286·8 (220·2-329·6) and 245·8 (215·2-302·3) kPa respectively (P= 0·192). There was no significant difference in PWRI between the two groups (P= 0·982). PWS and PWRI correlated positively with orthogonal diameter (both P<0·001). Participants with high PWS, but not PWRI, were more likely to have a ruptured AAA after adjusting for potential confounders (odds ratio 5·84, 95 per cent c.i. 1·22 to 27·95; P= 0·027). This association was not maintained in all sensitivity analyses. Conclusion: High aortic PWS had an inconsistent association with greater odds of aneurysm rupture in patients with a large AAA. [ABSTRACT FROM AUTHOR]

Background: Women with screen-detected invasive breast cancer who have macrometastatic disease on axillary sentinel lymph node biopsy (SLNB) are usually offered either surgical axillary node clearance (ANC) or axillary radiotherapy. These treatments can lead to significant complications for patients. The aim of this study was to identify a group of patients who may not require completion ANC. Methods: Data from the NHS Breast Screening Programme between 1 April 2012 and 31 March 2017 were interrogated to identify women with invasive breast carcinoma and a single sentinel lymph node (SLN) with macrometastatic disease who subsequently proceeded to completion ANC. Univariable and multivariable analyses were performed to identify patients with a single positive SLN who had no further lymph node metastasis on ANC. Results: Of the 2401 women included in the cohort, the presence of non-sentinel node disease was significantly affected by: the number of nodes obtained at SLNB (odds ratio (OR) 0.49 for retrieval of more than 1 node), invasive size of tumour (OR 1.63 for size greater than 20 mm), surgical treatment (OR 1.34 for mastectomy), human epidermal growth factor receptor (HER) 2 status (OR 0.71 for HER2 positivity), and patient age (OR 1.10 for age less than 50 years; OR 1.46 for age greater than 70 years). Patients aged less than 70 years, with tumour size smaller than 2 cm, more than one node retrieved on SLNB, and who had breast-conserving surgery had a lower chance of positive non-sentinel nodes on completion ANC compared with other patients. Conclusion: This study, of a purely screen-detected breast cancer cohort, identified a subset of patients who may be spared completion ANC in the event of a single axillary SLN with macrometastasis. [ABSTRACT FROM AUTHOR]

We report on the discovery and validation of TOI 813 b (TIC 55525572 b), a transiting exoplanet identified by citizen scientists in data from NASA's Transiting Exoplanet Survey Satellite (TESS) and the first planet discovered by the Planet Hunters TESS project. The host star is a bright (V  = 10.3 mag) subgiant (⁠|$R_\star =1.94\, R_\odot$|⁠ , |$M_\star =1.32\, M_\odot$|⁠). It was observed almost continuously by TESS during its first year of operations, during which time four individual transit events were detected. The candidate passed all the standard light curve-based vetting checks, and ground-based follow-up spectroscopy and speckle imaging enabled us to place an upper limit of |$2\, M_{\rm Jup}$| (99 per cent confidence) on the mass of the companion, and to statistically validate its planetary nature. Detailed modelling of the transits yields a period of |$83.8911 _{ - 0.0031 } ^ { + 0.0027 }$|  d, a planet radius of 6.71 ± 0.38  R ⊕ and a semimajor axis of |$0.423 _{ - 0.037 } ^ { + 0.031 }$|  AU. The planet's orbital period combined with the evolved nature of the host star places this object in a relatively underexplored region of parameter space. We estimate that TOI 813 b induces a reflex motion in its host star with a semi-amplitude of ∼6 m s−1, making this a promising system to measure the mass of a relatively long-period transiting planet. [ABSTRACT FROM AUTHOR]

The Transiting Exoplanet Survey Satellite, TESS , is currently carrying out an all-sky search for small planets transiting bright stars. In the first year of the TESS survey, a steady progress was made in achieving the mission's primary science goal of establishing bulk densities for 50 planets smaller than Neptune. During that year, the TESS 's observations were focused on the southern ecliptic hemisphere, resulting in the discovery of three mini-Neptunes orbiting the star TOI-125, a V  = 11.0 K0 dwarf. We present intensive HARPS radial velocity observations, yielding precise mass measurements for TOI-125b, TOI-125c, and TOI-125d. TOI-125b has an orbital period of 4.65 d, a radius of 2.726 ± 0.075 R E, a mass of 9.50 ± 0.88  M E, and is near the 2:1 mean motion resonance with TOI-125c at 9.15 d. TOI-125c has a similar radius of 2.759 ± 0.10  R E and a mass of 6.63 ± 0.99  M E, being the puffiest of the three planets. TOI-125d has an orbital period of 19.98 d and a radius of 2.93 ± 0.17  R E and mass 13.6 ± 1.2  M E. For TOI-125b and d, we find unusual high eccentricities of 0.19 ± 0.04 and |$0.17^{+0.08}_{-0.06}$|⁠ , respectively. Our analysis also provides upper mass limits for the two low-SNR planet candidates in the system; for TOI-125.04 (RP  = 1.36  R E, P  = 0.53 d), we find a 2σ upper mass limit of 1.6  M E, whereas TOI-125.05 (⁠|$R_P=4.2^{+2.4}_{-1.4}$|   R E, P  = 13.28 d) is unlikely a viable planet candidate with an upper mass limit of 2.7  M E. We discuss the internal structure of the three confirmed planets, as well as dynamical stability and system architecture for this intriguing exoplanet system. [ABSTRACT FROM AUTHOR]

We report the detection of a new planetary system orbiting the nearby M2.5V star GJ 357, using precision radial velocities from three separate echelle spectrographs, High Accuracy Radial velocity Planet Searcher (HARPS), High Resolution Echelle Spectrograph (HiRES), and Ultraviolet and Visible Echelle Spectrograph (UVES). Three small planets have been confirmed in the system, with periods of 9.125 ± 0.001, 3.9306 ± 0.0003, and 55.70 ± 0.05 d, and minimum masses of 3.33 ± 0.48, 2.09 ± 0.32, and 6.72 ± 0.94 M⊕, respectively. The second planet in our system, GJ 357 c, was recently shown to transit by the Transiting Exoplanet Survey Satellite (TESS), but we could find no transit signatures for the other two planets. Dynamical analysis reveals the system is likely to be close to coplanar, is stable on Myr time-scales, and places strong upper limits on the masses of the two non-transiting planets GJ 357 b and GJ 357 d of 4.25 and 11.20 M⊕, respectively. Therefore, we confirm the system contains at least two super-Earths, and either a third super-Earth or mini-Neptune planet. GJ 357 b  and  GJ 357 c are found to be close to a 7:3 mean motion resonance, however no libration of the orbital parameters was found in our simulations. Analysis of the photometric light curve of the star from the TESS , when combined with our radial velocities, reveals GJ 357 c has an absolute mass, radius, and density of |$2.248^{+0.117}_{-0.120}$|  M⊕, |$1.167^{+0.037}_{-0.036}$|  R⊕, and |$7.757^{+0.889}_{-0.789}$|  g cm−3, respectively. Comparison to super-Earth structure models reveals the planet is likely an iron-dominated world. The GJ 357 system adds to the small sample of low-mass planetary systems with well constrained masses, and further observational and dynamical follow-up is warranted to better understand the overall population of small multiplanet systems in the solar neighbourhood. [ABSTRACT FROM AUTHOR]

We report detection of quasi-periodic (1.5-d) dimming of HD 240779, the solar-mass primary in a 5 arcsec visual binary (also TIC 284730577), by the Transiting Exoplanet Survey Satellite. This dimming, as has been shown for other 'dipper' stars, is likely due to occultation by circumstellar dust. The barycentric space motion, lithium abundance, rotation, and chromospheric emission of the stars in this system point to an age of ≈125 Myr, and possible membership in the AB Doradus moving group. As such it occupies an important but poorly explored intermediate regime of stars with transient dimming between young stellar objects in star-forming regions and main-sequence stars, and between UX Orionis-type Ae/Be stars and M-type 'dippers'. HD 240779, but not its companion BD+10 714B, has Wide-field Infrared Survey Explorer (WISE) -detected excess infrared emission at 12 and 22 μ m indicative of circumstellar dust. We propose that infrared emission is produced by collisions of planetesimals during clearing of a residual disc at the end of rocky planet formation, and that quasi-periodic dimming is produced by the rapid disintegration of a ≳100 km planetesimal near the silicate evaporation radius. Further studies of this and similar systems will illuminate a poorly understood final phase of rocky planet formation like that which produced the inner Solar system. [ABSTRACT FROM AUTHOR]

We have identified a star, EPIC 249706694 (HD 139139), that was observed during K2 Campaign 15 with the Kepler extended mission that appears to exhibit 28 transit-like events over the course of the 87-d observation. The unusual aspect of these dips, all but two of which have depths of 200 ± 80 ppm, is that they exhibit no periodicity, and their arrival times could just as well have been produced by a random number generator. We show that no more than four of the events can be part of a periodic sequence. We have done a number of data quality tests to ascertain that these dips are of astrophysical origin, and while we cannot be absolutely certain that this is so, they have all the hallmarks of astrophysical variability on one of two possible host stars (a likely bound pair) in the photometric aperture. We explore a number of ideas for the origin of these dips, including actual planet transits due to multiple or dust emitting planets, anomalously large TTVs, S- and P-type transits in binary systems, a collection of dust-emitting asteroids, 'dipper-star' activity, and short-lived starspots. All transit scenarios that we have been able to conjure up appear to fail, while the intrinsic stellar variability hypothesis would be novel and untested. [ABSTRACT FROM AUTHOR]

We report the discovery of K2-161b, which was first identified as a planetary candidate from Kepler K2 photometry of Campaign 14, and whose planetary nature and orbital parameters were then confirmed with precision radial velocities. K2-161b is half as massive as Saturn (⁠|${\rm M_P}= 0.179 \pm 0.021 \, {\rm M_{J}}$|⁠), and has a radius of |${\rm R_P}= 0.840 \pm 0.011 \, {\rm R_J}$|⁠, which translates into a bulk density of |${\rm \rho _P}=0.37 \pm 0.05 \, \mathrm{g}\, \mathrm{cm}^{-3}$|⁠. K2-161b transits its slightly evolved G-type host star (⁠|${\rm M}_{\star }= 1.105 \pm 0.019 \, {\rm M}_{\odot }$|⁠, |${\rm R}_{\star }= 1.669 \pm 0.022 \, {\rm R}_{\odot }$|⁠) every 11.633 64 ± 0.000 10 d and presents a significantly eccentric orbit (e  = 0.420 ± 0.034). We estimate a relatively short circularization time-scale of 1.8 Gyr for the planet, but given the advanced age of the system we expect the planet to be engulfed by its evolving host star in ∼1 Gyr before the orbit circularizes. The low density of the planet coupled to the brightness of the host star (J  = 9.4) makes this system one of the best candidates known to date in the super-Neptune regime for atmospheric characterization via transmission spectroscopy, and to further study the transition region between ice and gas giant planets. [ABSTRACT FROM AUTHOR]

We report the direct detection of a fully convective, early-to-mid M-dwarf companion orbiting the star HD 86006, using ESO-SPHERE during Science Verification as part of the SAFARI program. HARPS+CORALIE radial velocity measurements first indicated a possible companion. Such work highlights the synergies that are now possible between these two observing methods. We studied the companion by comparing our observed spectra with BT-Settl models and template spectra, measuring spectral indices to obtain a spectral type, and used a joint radial velocity and astrometric fit to simulate the companion’s orbit. The companion was found to be 4.14 mag fainter than the primary in the H2 band, residing at a physical separation of ∼25 au, with a T eff and spectral type of 3321 ± 111 K and M 4.1 ± 1.1, respectively. We note that the age derived from BT-Settl models for such a star is too low by over two orders of magnitude, similar to other known field mid-M stars. We searched for the radial velocity companion to HD 90520 without any clear detection; however, we reached a low contrast level of ΔH2 = 10.3 mag (or 1.3 * 10−4) at 0.2 arcsec and 12.6 mag (or 10−5) at 0.5 arcsec, allowing us to rule out any low-mass companions with masses of 0.07 and 0.05 M⊙ at these separations. This discovery provides us with the exciting opportunity to better constrain the mass–luminosity relation for low-mass stars in the super metal-rich domain, expanding our understanding of the most-common types of stars and substellar objects. [ABSTRACT FROM AUTHOR]

We report the discovery of K2-232 b using photometric data of the Kepler K2 satellite coupled with ground-based spectroscopic observations. K2-232 b has a mass of MP = 0.397 ± 0.037 MJ, a radius of RP = 1.00 ± 0.020 RJ, and a moderately low equilibrium temperature of Teq = 1030 ± 15 K due to its relatively large star–planet separation of a = 0.1036 au. K2-232 b orbits its bright (V = 9.9) late F-type host star in an eccentric orbit (e = 0.258 ± 0.025) every 11.2 d, and is one of only four well-characterized warm Jupiters having host stars brighter than V = 10. We estimate a heavy element content of 20 ± 7 M⊕ for K2-232 b, which is consistent with standard models of giant planet formation. The bright host star of K2-232 b makes this system a well-suited target for detailed follow-up observations that will aid in the study of the atmospheres and orbital evolution of giant planets at moderate separations from their host stars. [ABSTRACT FROM AUTHOR]

Background: Revascularization is being used increasingly for the treatment of intermittent claudication and yet few studies have reported the long-term outcomes of this strategy. The aim of this study was to compare the long-term outcome of patients with intermittent claudication who underwent revascularization compared with a group initially treated without revascularization. Methods: Patients with symptoms of intermittent claudication and a diagnosis of peripheral arterial disease were recruited from outpatient clinics at three hospitals in Queensland, Australia. Based on variation in the practices of different vascular specialists, patients were either treated by early revascularization or received initial conservative treatment. Patients were followed in outpatient clinics using linked hospital admission record data. The primary outcome was the requirement for major amputation. Kaplan-Meier curves, Cox regression and competing risks analyses were used to compare major amputation rates. Results: Some 456 patients were recruited; 178 (39.0 per cent) underwent early revascularization and 278 (61.0 per cent) had initial conservative treatment. Patients were followed for amean(s.d.) of 5.00(3.37) years. The estimated 5-year major amputation rate was 6.2 and 0.7 per cent in patients undergoing early revascularization and initial conservative treatment respectively (P = 0.003). Early revascularization was associated with an increased requirement for major amputation in models adjusted for other risk factors (relative risk 5.40 to 4.22 in different models). Conclusion: Patients presenting with intermittent claudication who underwent early revascularization appeared to be at higher risk of amputation than those who had initial conservative treatment. [ABSTRACT FROM AUTHOR]

We present the discovery of K2-140b, a P = 6.57 d Jupiter-mass (MP = 1.019 ± 0.070MJup) planet transiting a V = 12.5 (G5-spectral type) star in an eccentric orbit (e = 0.120+0.056 -0.046) detected using a combination of K2 photometry and ground-based observations.With a radius of 1.095 ± 0.018 RJup, the planet has a bulk density of 0.726 ± 0.062 ρJup. The host star has a [Fe/H] of 0.12 ± 0.045, and from the K2 light curve, we find a rotation period for the star of 16.3 ± 0.1 d. This discovery is the 9th hot Jupiter from K2 and highlights K2's ability to detect transiting giant planets at periods slightly longer than traditional, ground-based surveys. This planet is slightly inflated, but much less than others with similar incident fluxes. These are of interest for investigating the inflation mechanism of hot Jupiters. [ABSTRACT FROM AUTHOR]

We present the first good evidence for exocomet transits of a host star in continuum light in data from the Kepler mission. The Kepler star in question, KIC 3542116, is of spectral type F2V and is quite bright at Kp = 10. The transits have a distinct asymmetric shape with a steeper ingress and slower egress that can be ascribed to objects with a trailing dust tail passing over the stellar disc. There are three deeper transits with depths of ̃0.1 per cent that last for about a day, and three that are several times more shallow and of shorter duration. The transits were found via an exhaustive visual search of the entire Kepler photometric data set, which we describe in some detail. We review the methods we use to validate the Kepler data showing the comet transits, and rule out instrumental artefacts as sources of the signals. We fit the transits with a simple dust-tail model, and find that a transverse comet speed of ~35-50 km s-1 and a minimum amount of dust present in the tail of ~1016 g are required to explain the larger transits. For a dust replenishment time of ~10 d, and a comet lifetime of only ~300 d, this implies a total cometary mass of ≪3 x 1017 g, or about the mass of Halley's comet.We also discuss the number of comets and orbital geometry that would be necessary to explain the six transits detected over the 4 yr of Kepler prime-field observations. Finally, we also report the discovery of a single comet-shaped transit in KIC 11084727 with very similar transit and host-star properties. [ABSTRACT FROM AUTHOR]

We aim to understand how stellar parameters such as mass and rotation impact the distribution of star-spots on the stellar surface. To this purpose, we have used Doppler imaging to reconstruct the surface brightness distributions of three fully convectiveMdwarfs with similar rotation rates. We secured high cadence spectral time series observations of the 5.5 au separation binary GJ 65, comprising GJ 65A (M5.5V, Prot=0.24 d) and GJ 65B (M6V, Prot=0.23 d). We also present new observations of GJ 791.2A (M4.5V, Prot=0.31 d). Observations of each star were made on two nights with UVES, covering a wavelength range from 0.64-1.03µm. The time series spectra reveal multiple line distortions that we interpret as cool star-spots and which are persistent on both nights suggesting stability on the time-scale of 3 d. Spots are recovered with resolutions down to 8.°3 at the equator. The global spot distributions for GJ 791.2A are similar to observations made a year earlier. Similar high latitude and circumpolar spot structure is seen on GJ 791.2A and GJ 65A. However, they are surprisingly absent on GJ 65B, which instead reveals more extensive, larger, spots concentrated at intermediate latitudes. All three stars show small amplitude latitude-dependent rotation that is consistent with solid body rotation. We compare our measurements of differential rotation with previous Doppler imaging studies and discuss the results in the wider context of other observational estimates and recent theoretical predictions. [ABSTRACT FROM AUTHOR]

Background It has been suggested that diabetes medications, such as metformin, may have effects that inhibit abdominal aortic aneurysm ( AAA) growth. The aim of this study was to examine the association of diabetes treatments with AAA growth in three patient cohorts. Methods AAA growth was studied using ultrasound surveillance in cohort 1, repeated CT in cohort 2 and more detailed repeat CT in cohort 3. Growth was estimated by the mean annual increase in maximum AAA diameter. Results A total of 1697 patients with an AAA were studied, of whom 118, 39 and 16 patients were prescribed metformin for the treatment of diabetes in cohorts 1, 2 and 3 respectively. Prescription of metformin was associated with a reduced likelihood of median or greater AAA growth in all three cohorts (cohort 1: adjusted odds ratio ( OR) 0·59, 95 per cent c.i. 0·39 to 0·87, P = 0·008; cohort 2: adjusted OR 0·38, 0·18 to 0·80, P = 0·011; cohort 3: adjusted OR 0·13, 0·03 to 0·61, P = 0·010). No other diabetes treatment was significantly associated with AAA growth in any cohort. Conclusion These findings suggest a potential role for metformin in limiting AAA growth. [ABSTRACT FROM AUTHOR]

We report results from the high-resolution spectral analysis of the 107 metal-rich (mostly [Fe/H] ≥ 7.67 dex) target stars from the Calan–Hertfordshire Extrasolar Planet Search programme observed with HARPS. Using our procedure of finding the best fit to the absorption line profiles in the observed spectra, we measure the abundances of Na, Mg, Al, Si, Ca, Ti, Cr, Mn, Fe, Ni, Cu and Zn, and then compare them with known results from different authors. Most of our abundances agree with these works at the level of ±0.05 dex or better for the stars we have in common. However, we do find systematic differences that make direct inferences difficult. Our analysis suggests that the selection of line lists and atomic line data along with the adopted continuum level influence these differences the most. At the same time, we confirm the positive trends of abundances versus metallicity for Na, Mn, Ni and, to a lesser degree, Al. A slight negative trend is observed for Ca, whereas Si and Cr tend to follow iron. Our analysis allows us to determine the positively skewed normal distribution of projected rotational velocities with a maximum peaking at 3 km s-1. Finally, we obtained a Gaussian distribution of microturbulent velocities that has a maximum at 1.2 km s-1 and a full width at half-maximum Δv1/2 = 0.35 km s-1, indicating that metal-rich dwarfs and subgiants in our sample have a very restricted range in microturbulent velocity. [ABSTRACT FROM AUTHOR]

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Background The aim was to evaluate the applicability of laparoscopic surgery in the treatment of primary rectal cancer in a training unit. Methods A cohort analysis was undertaken of consecutive patients undergoing elective surgery for primary rectal cancer over a 7-year interval. Data on patient and operative details, and short-term clinicopathological outcomes were collected prospectively and analysed on an intention-to-treat basis. Results A total of 306 patients (213 men, 69·6 per cent) of median (i.q.r.) age 67 (58-73) years with a median body mass index of 26·6 (23·9-29·9) kg/m2 underwent surgery. Median tumour height was 8 (6-11) cm from the anal verge, and 46 patients (15·0 per cent) received neoadjuvant radiotherapy. Seven patients (2·3 per cent) were considered unsuitable for laparoscopic surgery and underwent open resection; 299 patients (97·7 per cent) were suitable for laparoscopic surgery, but eight were randomized to open surgery as part of an ongoing trial. Some 291 patients (95·1 per cent) underwent a laparoscopic procedure, with conversion required in 29 (10·0 per cent). Surgery was partially or completely performed by trainees in 72·4 per cent of National Health Service patients (184 of 254), whereas private patients underwent surgery primarily by consultants. Median postoperative length of stay for all patients was 6 days and the positive circumferential resection margin rate was 4·9 per cent (15 of 306). Conclusion Supervised trainees can perform routine laparoscopic rectal cancer resection. [ABSTRACT FROM AUTHOR]

Background Muscle depletion is characterized by reduced muscle mass (myopenia), and increased infiltration by intermuscular and intramuscular fat (myosteatosis). This study examined the role of particular body composition profiles as prognostic markers for patients with colorectal cancer undergoing curative resection. Methods Patients with colorectal cancer undergoing elective surgical resection between 2006 and 2011 were included. Lumbar skeletal muscle index ( LSMI), visceral adipose tissue ( VAT) surface area and mean muscle attenuation ( MA) were calculated by analysis of CT images. Reduced LSMI (myopenia), increased VAT (visceral obesity) and low MA (myosteatosis) were identified using predefined sex-specific skeletal muscle index values. Univariable and multivariable Cox regression models were used to determine the role of different body composition profiles on outcomes. Results Some 805 patients were identified, with a median follow-up of 47 (i.q.r. 24·9-65·6) months. Multivariable analysis identified myopenia as an independent prognostic factor for disease-free survival (hazard ratio ( HR) 1·53, 95 per cent c.i. 1·06 to 2·39; P = 0·041) and overall survival ( HR 1·70, 1·25 to 2·31; P < 0·001). The presence of myosteatosis was associated with prolonged primary hospital stay ( P = 0·034), and myopenic obesity was related to higher 30-day morbidity ( P = 0·019) and mortality ( P < 0·001) rates. Conclusion Myopenia may have an independent prognostic effect on cancer survival for patients with colorectal cancer. Muscle depletion may represent a modifiable risk factor in patients with colorectal cancer and needs to be targeted as a relevant endpoint of health recommendations. [ABSTRACT FROM AUTHOR]

We report the detection of sixteen binary systems from the Anglo-Australian Planet Search. Solutions to the radial velocity data indicate that the stars have companions orbiting with a wide range of masses, eccentricities and periods. Three of the systems potentially contain brown-dwarf companions while another two have eccentricities that place them in the extreme upper tail of the eccentricity distribution for binaries with periods less than 1000 d. For periods up to 12 years, the distribution of our stellar companion masses is fairly flat, mirroring that seen in other radial velocity surveys, and contrasts sharply with the current distribution of candidate planetary masses, which rises strongly below 10 MJ. When looking at a larger sample of binaries that have FGK star primaries as a function of the primary star metallicity, we find that the distribution maintains a binary fraction of ~43 ± 4 per cent between -1.0 and +0.6 dex in metallicity. This is in stark contrast to the giant exoplanet distribution. This result is in good agreement with binary formation models that invoke fragmentation of a collapsing giant molecular cloud, suggesting that this is the dominant formation mechanism for close binaries and not fragmentation of the primary star's remnant protoplanetary disc. [ABSTRACT FROM AUTHOR]

We present a new Y dwarf, WISE J030449.03−270508.3, confirmed from a candidate sample designed to pick out low-temperature objects from the Wide-field Infrared Survey Explorer (WISE) data base. The new object is typed Y0pec following a visual comparison with spectral standards, and lies at a likely distance of 10–17 pc. Its tangential velocity suggests thin disc membership, but it shows some spectral characteristics that suggest that it may be metal poor and/or older than previously identified Y0 dwarfs. Based on trends seen for warmer late-type T dwarfs, the Y-band flux peak morphology is indicative of sub-solar metallicity, and the enhanced red wing of the J-band flux peak offers evidence for high gravity and/or low metallicity (with associated model trends suggesting an age closer to ∼10 Gyr and mass in the range 0.02–0.03 M⊙). This object may thus be extending the population parameter space of the known Y0 dwarfs. [ABSTRACT FROM PUBLISHER]

Background Complete mesocolic excision with central vascular ligation ( CME) produces an optimal colonic cancer specimen. The ability of expert laparoscopic surgeons to produce equivalent specimens is unknown. Methods Fresh specimen photographs and clinicopathological data from patients undergoing laparoscopically assisted CME at St Mark's Hospital, Harrow, were submitted for independent pathological review. Surgery was performed by a mixture of consultant specialists and trainees under consultant specialist supervision, between February 2010 and July 2011. The planes of surgery were graded and tissue morphometry was performed using standard methods. The results were compared with published data from open CME and non- CME surgery. Results In total, 69 patients were identified, and in 96 per cent resection was performed completely or partially by surgical trainees. Laparoscopic CME produced a similar specimen to open CME. The laparoscopic mesocolic plane resection rate was similar to that for open surgery (90 versus 88 per cent). The distance between the bowel wall and site of vascular division was similar for laparoscopic and open right-sided CME (92 versus 95 mm respectively). The corresponding values for left-sided CME were also similar (103 versus 107 mm). Compared with values from two non-CME series, laparoscopic CME had a higher mesocolic plane rate (90 versus 40 and 48 per cent), and resected more tissue between the bowel wall and the vascular division (right-sided: 92 versus 72 and 76 mm; left-sided: 103 versus 85 and 70 mm). The lymph node yield remained low following laparoscopic CME compared with open CME (median 18 versus 32; P < 0·001) and identical to that of non- CME surgery (median 18). Conclusion Laparoscopic CME can be performed to the same standard as open surgery by supervised trainees. However, this did not increase the lymph node yield. [ABSTRACT FROM AUTHOR]

Background The literature on laparoscopic restorative proctectomy ( RP) and proctocolectomy ( RPC) is limited. This study compared clinical outcomes of laparoscopic RP and RPC with those of conventional open surgery at one centre. Methods Data were analysed from consecutive patients undergoing RPC and RP between November 2006 and November 2011. A standard laparoscopic technique was developed during the first 2 years, performed by two laparoscopic surgeons, with selection of patients who had not previously undergone open colectomy. Study endpoints included postoperative length of stay, 30-day morbidity, readmission, reoperation, pouch function and failure. Results A total of 207 patients were included; open surgery was performed in 131 (63·3 per cent) and a laparoscopic procedure in 76 (36·7 per cent). There were no significant differences in patient demographics. The conversion rate was 9 per cent (7 of 76). The median (i.q.r.) duration of operation was shorter for open than for laparoscopic procedures: 208 (178-255) versus 285 (255-325) min respectively ( P < 0·001). Laparoscopic RPC had a shorter length of stay: median (i.q.r.) 6 (4-8) versus 8 (7-12) days ( P < 0·001). The rate of minor complications was lower in the laparoscopic group (33 versus 50·4 per cent; odds ratio ( OR) 0·48, 95 per cent confidence interval 0·27 to 0·87).There were no significant differences in total complications (51 per cent after laparoscopy versus 61·5 per cent after open surgery; OR 0·66, 0·37 to 1·17), anastomotic leakage, major morbidity, 30-day readmission, reoperation and stoma closure rates. Pouch failure (including permanent stoma) occurred in 14 (7·7 per cent) of 181 patients. Three patients died, all in the open surgery group. Conclusion Laparoscopic RPC is feasible with some short-term advantages. [ABSTRACT FROM AUTHOR]

The hunt for Earth analogue planets orbiting Sun-like stars has forced the introduction of novel methods to detect signals at, or below, the level of the intrinsic noise of the observations. We present a new global periodogram method that returns more information than the classic Lomb–Scargle periodogram method for radial velocity signal detection. Our method uses the minimum mean-squared error as a framework to determine the optimal number of genuine signals present in a radial velocity timeseries using a global search algorithm, meaning that we can discard noise spikes from the data before a follow-up analysis. This method also allows us to determine the phase and amplitude of the signals we detect, meaning that we can track these quantities as a function of time to test if the signals are stationary or non-stationary. We apply our method to the radial velocity data for GJ876 as a test system to highlight how the phase information can be used to select against the non-stationary sources of detected signals in radial velocity data, such as rotational modulation of star spots. Analysis of this system yields two new statistically significant signals in the combined Keck and HARPS velocities with periods of 10 and 15 d. Although a planet with a period of 15 d would relate to a Laplace resonant chain configuration with three of the other planets (8:4:2:1), we stress that the follow-up dynamical analyses are needed to test the reliability of such a six-planet system. [ABSTRACT FROM AUTHOR]

We present a new sample of mid-L to mid-T dwarfs with effective temperatures of 1100–1700 K selected from the UKIDSS Large Area Survey (LAS) and confirmed with infrared spectra from X-shooter/Very Large Telescope. This effective temperature range is especially sensitive to the formation history of Galactic brown dwarfs and allows us to constrain the form of the sub-stellar birth rate, with sensitivity to differentiate between a flat (stellar like) birth rate and an exponentially declining form. We present the discovery of 63 new L and T dwarfs from the UKIDSS LAS DR7, including the identification of 12 likely unresolved binaries, which form the first complete sub-set from our programme, covering 495 square degrees of sky, complete to J = 18.1. We compare our results for this sub-sample with simulations of differing birth rates for objects of masses 0.10–0.03 M⊙ and ages 1–10 Gyr. We find that the more extreme birth rates (e.g. a halo type form) can likely be excluded as the true form of the birth rate. In addition, we find that although there is substantial scatter we find a preference for a mass function, with a power-law index α in the range −1 < α < 0 that is consistent (within the errors) with the studies of late T dwarfs. [ABSTRACT FROM PUBLISHER]

Background: With the adoption of enhanced recovery and emerging new modalities of analgesia after laparoscopic colorectal resection (LCR), the role of epidural analgesia has been questioned. This pilot trial assessed the feasibility of a randomized controlled trial (RCT) comparing epidural analgesia and use of a local anaesthetic wound infusion catheter (WIC) following LCR. Methods: Between April 2010 and May 2011, patients undergoing elective LCR in two centres were randomized to analgesia via epidural or WIC. Sham procedures were used to blind surgeons, patients and outcome assessors. The primary outcome was the feasibility of a large RCT, and all outcomes for a definitive trial were tested. The success of blinding was assessed using a mixed-methods approach. Results: Forty-five patients were eligible, of whom 34 were randomized (mean(s.d.) age 70(11·8) years). Patients were followed up per-protocol; there were no deaths, and five patients had a total of six complications. Challenges with capturing pain data were identified and resolved. Mean(s.d.) pain scores on the day of discharge were 1·9(3·1) in the epidural group and 0·7(0·7) in the WIC group. Median length of stay was 4 (range 2-35, interquartile range 3-5) days. Mean use of additional analgesia (intravenous morphine equivalents) was 12 mg in the WIC arm and 9 mg in the epidural arm. Patient blinding was successful in both arms. Qualitative interviews suggested that patients found participation in the trial acceptable and that they would consider participating in a future trial. Conclusion: A blinded RCT investigating the role of epidural and WIC administration for postoperative analgesia following LCR is feasible. Rigorous standard operating procedures for data collection are required. Copyright © 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Although surgical resection remains the central element in curative treatment of gastrointestinal cancer, increasing emphasis and resource has been focused on neoadjuvant or adjuvant therapy. Developments in these modalities have improved outcomes, but far less attention has been paid to improving oncological outcomes through optimization of perioperative care. Methods: A narrative review is presented based on available and updated literature in English and the authors' experience with enhanced recovery research. Results: A range of perioperative factors (such as lifestyle, co-morbidity, anaemia, sarcopenia, medications, regional analgesia and minimal access surgery) are modifiable, and can be optimized to reduce short- and long-term morbidity and mortality, improve functional capacity and quality of life, and possibly improve oncological outcome. The effect on cancer-free and overall survival may be of equal magnitude to that achieved by many adjuvant oncological regimens. Modulation of core factors, such as nutritional status, systemic inflammation, and surgical and disease-mediated stress, probably influences the host's immune surveillance and defence status both directly and through reduced postoperative morbidity. Conclusion: A wider view on long-term effects of expanded or targeted enhanced recovery protocols is warranted. Copyright © 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT We present the first results from our Red Optical Planet Survey to search for low-mass planets orbiting late-type dwarfs (M5.5V-M9V) in their habitable zones. Our observations with the red arm of the Magellan Inamori Kyocera Echelle spectrograph (0.5-0.9 m) at the 6.5-m Magellan Clay telescope at Las Campanas Observatory indicate that ≥92 per cent of the flux lies beyond 0.7 m. We use a novel approach that is essentially a hybrid of the simultaneous iodine and ThAr methods for determining precision radial velocities. We apply least squares deconvolution to obtain a single high signal-to-noise ratio (S/N) stellar line for each spectrum and cross-correlate against the simultaneously observed telluric line profile, which we derive in the same way. Utilizing the 0.62-0.90 m region, we have achieved an rms precision of 10 ms−1 for an M5.5V spectral type star with spectral S/N ∼ 160 on 5-min time-scales. By M8V spectral type, a precision of ∼30 ms−1 at S/N = 25 is suggested, although more observations are needed. An assessment of our errors and scatter in the radial velocity points hints at the presence of stellar radial velocity variations. Of our sample of seven stars, two show radial velocity signals at 6σ and 10σ of the cross-correlation uncertainties. We find that chromospheric activity (via Hα variation) does not have an impact on our measurements and are unable to determine a relationship between the derived photospheric line profile morphology and radial velocity variations without further observations. If the signals are planetary in origin, our findings are consistent with estimates of Neptune mass planets that predict a frequency of 13-27 per cent for early M dwarfs. Our current analysis indicates the we can achieve a sensitivity that is equivalent to the amplitude induced by a 6 M⊕ planet orbiting in the habitable zone. Based on simulations, we estimate that <10 M⊕ habitable zone planets will be detected in a new stellar mass regime, with ≤20 epochs of observations. Higher resolution and greater instrument stability indicate that photon-limited precisions of 2 ms−1 are attainable on moderately rotating M dwarfs (with vsin i≤ 5 km s−1) using our technique. [ABSTRACT FROM AUTHOR]

ABSTRACT We describe the procedure to determine effective temperatures, rotational velocities, microturbulent velocities and chemical abundances in the atmospheres of Sun-like stars. We use independent determinations of iron abundances using the fits to the observed Fe i and Fe ii atomic absorption lines. We choose the best solution from the fits to these spectral features for the model atmosphere that provides the best confidence in the determined log N(Fe), Vt and v sin i. Computations were performed in the framework of local thermodynamic equilibrium. Blending effects were accounted for explicitly. First, we compute the abundance of iron for a set of adopted microturbulent velocities. In some cases, a few points of log N(Fe i) = log N(Fe ii) can be found. To determine the most self-consistent effective temperature and microturbulent velocity in any star's atmosphere, we used an additional constraint where we minimize the dependence of the derived abundances of Fe i and Fe ii on the excitation potential of the corresponding lines. Using this procedure we analyse the spectra of the Sun and two well-known solar-type stars, HD 1835 and HD 10700, to determine their abundances, microturbulent velocity and rotational velocity. Our approach allows us to determine self-consistent values for the effective temperatures, abundances, Vt and v sin i. For the Sun, we obtain the best agreement for a model atmosphere of Teff/log g/[Fe/H] = 5777/4.44/0.0, iron abundances and microturbulent velocities of log N(Fe) = 4.44, Vt= 0.75 km s−1, for the Fe i lines, and log N(Fe) =−4.47 and Vt= 1.5 km s−1 for the Fe ii lines. Furthermore, abundances of other elements obtained from the fits of their absorption features agree well enough (±0.1 dex) with the known values for the Sun. We determined a rotational velocity of v sin i= 1.6 ± 0.3 km s−1 for the spectrum of the Sun as a star. For HD 1835, the self-consistent solution for Fe i and Fe ii lines log N(Fe) =+0.2 was obtained with a model atmosphere of 5807/4.47/+0.2 and microturbulent velocity of Vt= 0.75 km s−1, and leads to v sin i= 7.2 ± 0.5 km s−1. For HD 10700, the self-consistent solution log N(Fe) =−4.93 was obtained using a model atmosphere of 5383/4.59/−0.6 and microturbulent velocity of Vt= 0.5 km s−1. The Fe i and Fe ii lines give rise to a v sin i= 2.4 ± 0.4 km s−1. Using Teff found from the ionization equilibrium parameters for all three stars, we found abundances of a number of other elements: Ti, Ni, Ca, Si and Cr. We show that uncertainties in the adopted values of Teff of 100 K and Vt of 0.5 km s−1 change the abundances of elements up to 0.1 and 0.2 dex, respectively. Galactic abundance variations can generally be larger than this measurement precision and therefore we can study abundance variations throughout the Galaxy. [ABSTRACT FROM AUTHOR]

ABSTRACT We describe the procedure to determine effective temperatures, rotational velocities, microturbulent velocities and chemical abundances in the atmospheres of Sun-like stars. We use independent determinations of iron abundances using the fits to the observed Fe i and Fe ii atomic absorption lines. We choose the best solution from the fits to these spectral features for the model atmosphere that provides the best confidence in the determined log N(Fe), Vt and v sin i. Computations were performed in the framework of local thermodynamic equilibrium. Blending effects were accounted for explicitly. First, we compute the abundance of iron for a set of adopted microturbulent velocities. In some cases, a few points of log N(Fe i) = log N(Fe ii) can be found. To determine the most self-consistent effective temperature and microturbulent velocity in any star's atmosphere, we used an additional constraint where we minimize the dependence of the derived abundances of Fe i and Fe ii on the excitation potential of the corresponding lines. Using this procedure we analyse the spectra of the Sun and two well-known solar-type stars, HD 1835 and HD 10700, to determine their abundances, microturbulent velocity and rotational velocity. Our approach allows us to determine self-consistent values for the effective temperatures, abundances, Vt and v sin i. For the Sun, we obtain the best agreement for a model atmosphere of Teff/log g/[Fe/H] = 5777/4.44/0.0, iron abundances and microturbulent velocities of log N(Fe) = 4.44, Vt= 0.75 km s−1, for the Fe i lines, and log N(Fe) =−4.47 and Vt= 1.5 km s−1 for the Fe ii lines. Furthermore, abundances of other elements obtained from the fits of their absorption features agree well enough (±0.1 dex) with the known values for the Sun. We determined a rotational velocity of v sin i= 1.6 ± 0.3 km s−1 for the spectrum of the Sun as a star. For HD 1835, the self-consistent solution for Fe i and Fe ii lines log N(Fe) =+0.2 was obtained with a model atmosphere of 5807/4.47/+0.2 and microturbulent velocity of Vt= 0.75 km s−1, and leads to v sin i= 7.2 ± 0.5 km s−1. For HD 10700, the self-consistent solution log N(Fe) =−4.93 was obtained using a model atmosphere of 5383/4.59/−0.6 and microturbulent velocity of Vt= 0.5 km s−1. The Fe i and Fe ii lines give rise to a v sin i= 2.4 ± 0.4 km s−1. Using Teff found from the ionization equilibrium parameters for all three stars, we found abundances of a number of other elements: Ti, Ni, Ca, Si and Cr. We show that uncertainties in the adopted values of Teff of 100 K and Vt of 0.5 km s−1 change the abundances of elements up to 0.1 and 0.2 dex, respectively. Galactic abundance variations can generally be larger than this measurement precision and therefore we can study abundance variations throughout the Galaxy. [ABSTRACT FROM AUTHOR]

ABSTRACT We present new ages and abundance measurements for the pre-main-sequence star PZ Telescopii (more commonly known as PZ Tel). PZ Tel was recently found to host a young and low-mass companion. Such companions, whether they are brown dwarfs or planetary systems, can attain benchmark status by detailed study of the properties of the primary, and then evolutionary and bulk characteristics can be inferred for the companion. Using Fibre-fed Extended Range Optical Spectrograph spectra, we have measured atomic abundances (e.g. Fe and Li) and chromospheric activity for PZ Tel and used these to obtain the metallicity and age estimates for the companion. We have also determined the age independently using the latest evolutionary models. We find PZ Tel A to be a rapidly rotating ( v sin i= 73 ± 5 km s−1), approximately solar metallicity star [log N(Fe) =−4.37 ± 0.06 dex or [Fe/H] = 0.05 ± 0.20 dex]. We measure a non-local thermodynamic equilibrium lithium abundance of log N(Li) = 3.1 ± 0.1 dex, which from depletion models gives rise to an age of 7 Myr for the system. Our measured chromospheric activity ( of −4.12) returns an age of 26 ± 2 Myr, as does fitting pre-main-sequence evolutionary tracks (τevol= 22 ± 3 Myr), both of these are in disagreement with the lithium age. We speculate on reasons for this difference and introduce new models for lithium depletion that incorporate both rotation and magnetic field effects. We also synthesize solar, metal-poor and metal-rich substellar evolutionary models to better determine the bulk properties of PZ Tel B, showing that PZ Tel B is probably more massive than previous estimates, meaning the companion is not a giant exoplanet, even though a planetary-like formation origin can go some way to describing the distribution of benchmark binaries currently known. We show how PZ Tel B compares to other currently known age and metallicity benchmark systems and try to empirically test the effects of dust opacity as a function of metallicity on the near-infrared colours of brown dwarfs. Current models suggest that in the near-infrared observations are more sensitive to low-mass companions orbiting more metal rich stars. We also look for trends between infrared photometry and metallicity amongst a growing population of substellar benchmark objects, and identify the need for more data in mass-age-metallicity parameter space. [ABSTRACT FROM AUTHOR]

ABSTRACT We present a hierarchical triple star system (KIC 9140402) where a low-mass eclipsing binary orbits a more massive third star. The orbital period of the binary (4.988 29 d) is determined by the eclipse times seen in photometry from NASA's Kepler spacecraft. The periodically changing tidal field, due to the eccentric orbit of the binary about the tertiary, causes a change in the orbital period of the binary. The resulting eclipse timing variations provide insight into the dynamics and architecture of this system and allow the inference of the total mass of the binary (0.424 ± 0.017 M⊙) and the orbital parameters of the binary about the central star. [ABSTRACT FROM AUTHOR]

We have used blue near-infrared colours to select a group of 12 spectroscopically confirmed United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) T dwarfs later than T4. From amongst these, we identify the first two kinematic halo T-dwarf candidates. Blue near-infrared colours have been attributed to collisionally induced hydrogen absorption, which is enhanced by either high surface gravity or low metallicity. Proper motions are measured and distances estimated, allowing the determination of tangential velocities. and components are estimated for our objects by assuming . From this, ULAS J0926+0835 is found to have km s and km s, and ULAS J1319+1209 is found to have km s and km s. These values are consistent with potential halo membership. However, these are not the bluest objects in our selection. The bluest is ULAS J1233+1219, with , and surprisingly this object is found to have young disc-like and . Our sample also contains Hip 73786B, companion to the metal-poor K5 dwarf Hip 73786. Hip 73786 is a metal-poor star, with and is located at a distance of 19 pc. space velocity components are calculated for Hip 73786A and B, finding that km s, km s and km s. From the properties of the primary, Hip 73786B is found to be at least -Gyr old. As a metal-poor object, Hip 73786B represents an important addition to the sample of known T dwarf benchmarks. [ABSTRACT FROM AUTHOR]

The Kepler mission is providing photometric data of exquisite quality for the asteroseismic study of different classes of pulsating stars. These analyses place particular demands on the pre-processing of the data, over a range of time-scales from minutes to months. Here, we describe processing procedures developed by the Kepler Asteroseismic Science Consortium to prepare light curves that are optimized for the asteroseismic study of solar-like oscillating stars in which outliers, jumps and drifts are corrected. [ABSTRACT FROM AUTHOR]

We present our analysis of the long-cadence Kepler data for the well-studied Blazhko star RR Lyr, gathered during the first two quarters of the satellite's observations and covering a total of 127 d. Besides being of great importance for our understanding of RR Lyrae stars in general, these RR Lyr data can be regarded as a case study for observations of bright stars with Kepler. Kepler can perform high-precision photometry on targets like RR Lyr, as the saturated flux is conserved to a very high degree. The Kepler data on RR Lyr are revolutionary in several respects. Even with long-cadence sampling (one measurement per 29.4 min), the unprecedented precision ( mmag) of the Kepler photometry allows the study of the star's extreme light-curve variations in detail. The multiplet structures at the main frequency and its harmonics, typical for Blazhko stars, are clearly detected up to the quintuplets. For the first time, photometric data of RR Lyr reveal the presence of half-integer frequencies, linked to a period-doubling effect. This phenomenon may be connected to the still unexplained Blazhko modulation. Moreover, with three observed Blazhko cycles at our disposal, we observe that there is no exact repetition in the light-curve changes from one modulation cycle to the next for RR Lyr. This may be due to additional periodicities in the star, or to transient or quasi-periodic changes. [ABSTRACT FROM AUTHOR]

ABSTRACT We present the discovery of the first T dwarf + white dwarf binary system LSPM 1459+0857 AB, confirmed through common proper motion and spectroscopy. The white dwarf is a high proper motion object from the LSPM catalogue that we confirm spectroscopically to be a relatively cool ( Teff= 5535 ± 45 K) and magnetic ( B∼ 2 MG) hydrogen-rich white dwarf, with an age of at least 4.8 Gyr. The T dwarf is a recent discovery from the UKIRT Infrared Deep Sky Survey (ULAS 1459+0857) and has a spectral type of T4.5 ± 0.5 and a distance in the range 43-69 pc. With an age constraint (inferred from the white dwarf) of >4.8 Gyr, we estimate Teff= 1200-1500 K and log g= 5.4-5.5 for ULAS 1459+0857, making it a benchmark T dwarf with well-constrained surface gravity. We also compare the T dwarf spectra with the latest LYON group atmospheric model predictions, which, despite some shortcomings, are in general agreement with the observed properties of ULAS 1459+0857. The separation of the binary components (16 500-26 500 au or 365 arcsec on the sky) is consistent with an evolved version of the more common brown dwarf + main-sequence (MS) binary systems now known, and although the system has a wide separation, it is shown to be statistically robust as a non-spurious association. The observed colours of the T dwarf show that it is relatively bright in the z band compared to other T dwarfs of similar type, and further investigation is warranted to explore the possibility that this could be a more generic indicator of older T dwarfs. Future observations of this binary system will provide even stronger constraints on the T dwarf properties, and additional systems will combine to give a more comprehensively robust test of the model atmospheres in this temperature regime. [ABSTRACT FROM AUTHOR]

We present our analysis of Kepler observations of 29 RR Lyrae stars, based on 138 d of observation. We report precise pulsation periods for all stars. Nine of these stars had incorrect or unknown periods in the literature. 14 of the stars exhibit both amplitude and phase Blazhko modulations, with Blazhko periods ranging from 27.7 to more than 200 d. For V445 Lyr, a longer secondary variation is also observed in addition to its 53.2-d Blazhko period. The unprecedented precision of the Kepler photometry has led to the discovery of the the smallest modulations detected so far. Moreover, additional frequencies beyond the well-known harmonics and Blazhko multiplets have been found. These frequencies are located around the half-integer multiples of the main pulsation frequency for at least three stars. In four stars, these frequencies are close to the first and/or second overtone modes. The amplitudes of these periodicities seem to vary over the Blazhko cycle. V350 Lyr, a non-Blazhko star in our sample, is the first example of a double-mode RR Lyrae star that pulsates in its fundamental and second overtone modes. [ABSTRACT FROM AUTHOR]

We study a target sample of 68 low-mass objects (with spectral types in the range M4.5-L1) previously selected via photometric and astrometric criteria, as possible members of five young moving groups: the Local Association (Pleiades moving group, age = 20-150 Myr), the Ursa Mayor group (Sirius supercluster, age = 300 Myr), the Hyades supercluster (age = 600 Myr), IC 2391 supercluster (age = 35-55 Myr) and the Castor moving group (age = 200 Myr). In this paper, we assess their membership by using different kinematic and spectroscopic criteria. We use high-resolution echelle spectroscopic observations of the sample to measure accurate radial velocities. Distances are calculated and compared to those of the moving group from the literature, we also calculate the kinematic Galactic components ( U, V, W) of the candidate members and apply kinematic criterion of membership to each group. In addition, we measure rotational velocities () to place further constraints on membership of kinematic members. We find that 49 targets have young disc kinematics and that 36 of them possibly belong to one of our five moving groups. From the young disc target objects, 31 have rotational velocities in agreement with them belonging to the young disc population. We also find that one of our moving group candidates, 2MASS0123−3610, is a low-mass double lined spectroscopic binary, with probable spectral types around M7. [ABSTRACT FROM AUTHOR]

BACKGROUND: The influence of elevated serum progesterone levels during in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles on pregnancy rates is a matter of continued debate among fertility clinicians. Efforts to resolve this question have been impeded by the various assays used to measure progesterone and the different, arbitrary threshold values for defining ‘high’ progesterone levels. [ABSTRACT FROM PUBLISHER]

We identify 806 ultracool dwarfs (of which 34 are newly discovered L dwarfs) from their Sloan Digital Sky Survey (SDSS) riz photometry and obtain proper motions through cross-matching with the United Kingdom Infrared Telescope Infrared Deep Sky Survey (UKIDSS) and Two-Micron All-Sky Survey (2MASS). Proper-motion and distance constraints show that nine of our ultracool dwarfs are members of widely separated binary systems: SDSS 0101 (K5V+M9.5V), SDSS 0207 (M1.5V+L3V), SDSS 0832 (K3III+L3.5V), SDSS 0858 (M4V+L0V), SDSS 0953 (M4V+M9.5V), SDSS 0956 (M2V+M9V), SDSS 1304 (M4.5V+L0V), SDSS 1631 (M5.5V+M8V) and SDSS 1638 (M4V+L0V). One of these (SDSS 0832) is shown to be a companion to the bright K3 giant η Cancri. Such primaries can provide age and metallicity constraints for any companion objects, yielding excellent benchmark objects. η Cancri AB is the first wide ultracool dwarf + giant binary system identified. We present new observations and analysis that constrain the metallicity of η Cancri A to be near-solar, and use recent evolutionary models to constrain the age of the giant to be 2.2–6.1 Gyr. If η Cancri B is a single object, we estimate its physical attributes to be mass = 63–82 = 1800 ± 150 K, . Its colours are non-typical when compared with other ultracool dwarfs, and we also assess the possibility that η Cancri B is itself an unresolved binary, showing that the combined light of an L4 + T4 system could provide a reasonable explanation for its colours. [ABSTRACT FROM AUTHOR]

We associate 132 low-mass ultracool dwarfs in the southern hemisphere as candidate members of five moving groups (MGs) using photometric and astrometric selection techniques. Of these objects, we present high-resolution spectroscopy for seven candidates and combine these with previous measurements from the literature to determine spectral types and radial velocities. We thus constrain distance and space motion spectroscopically, allowing the kinematic membership of the MGs to be assessed. Possible membership of MGs has allowed ages and metallicities to be constrained for these objects and evolutionary models have been used to estimate their mass. We estimate that up to ∼75 of our candidate MG members should be genuine, and discuss future work that will confirm and exploit this major new sample. [ABSTRACT FROM AUTHOR]

We report the discovery of a brown dwarf on an eccentric orbit and with a semimajor axis that places it in the brown dwarf desert region around the star HD 191760. The star has a spectral type of G3IV/V and a metallicity ([Fe/H]) of 0.29 dex. HD 191760 adds to the small number of metal-rich stars with brown dwarf companions. The brown dwarf (HD ) is found to have an orbital period of d and semimajor axis of , placing it firmly in the brown dwarf desert. The eccentricity of HD is found to be , meaning it reaches as close as 0.5 au from the host star. Dynamical simulations indicate that no inner planets could reside at separations beyond ∼0.17 au due to the disastrous gravity imposed by HD . In addition to these first results, we also refine the orbits found for the exoplanets around the stars HD 48265, HD 143361 and HD 154672. All one-planet solutions are in agreement with those previously published by the Magellan Planet Search. [ABSTRACT FROM AUTHOR]

Topoisomerase II poisons are an established part of best clinical practice for the treatment of a number of solid tumours and haematological malignancies. However, toxicity and resistance to chemotherapeutic drugs often complicate the treatment. Furthermore, topoisomerase II poisons can also induce sister chromatid exchange, chromosomal recombination and chromosome aberrations and are associated with a significant risk of secondary leukaemia. It would therefore be of great clinical benefit if the efficacy of topoisomerase II inhibitors could be enhanced without the increased toxic side effects. It is proposed that clinical agents targeting topoisomerase II can be enhanced by inhibiting proteins that modulate topoisomerase II. The aim is to identify proteins, that by the nature of their interaction with topoisomerase II, represent putative drug targets. [ABSTRACT FROM AUTHOR]