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Here we will briefly describe the commissioning of the Double ElectroStatic Ion Ring ExpEriment (DESIREE) facility at Stockholm University, Sweden. This device uses purely electrostatic focussing and deflection elements and allows ion beams of opposite charge to be confined under extreme high vacuum and cryogenic conditions in separate “rings” and then merged over a common straight section. This apparatus allows for studies of interactions between cations and anions at very low and well-defined centre-of-mass energies (down to a few meV) and at very low internal temperatures (down to a few K).

Combined results are now available from a 15 year long search for Jupiter analogues around solar-type stars using the ESO CAT + CES, ESO 3.6 m + CES, and ESO 3.6 m + HARPS instruments. They comprise planet (co-)discoveries (ι Hor and HR 506) and confirmations (three planets in HR 3259) as well as non-confirmations of planets (HR 4523 and ɛ Eri) announced elsewhere. A long-term trend in ɛ Ind found by our survey is probably attributable to a Jovian planet with a period >30 yr, but we cannot fully exclude stellar activity effects as the cause. A 3.8 year periodic variation in HR 8323 can be attributed to stellar activity.

Context. Neutron-capture elements represent an important nucleosynthetic channel in the study of the Galactic chemical evolution of stellar populations. For stellar populations behind significant extinction, such as those in the Galactic centre and along the Galactic plane, abundance analyses based on near-infrared (NIR) spectra are necessary. Previously, spectral lines from the neutron-capture elements, such as copper (Cu), cerium (Ce), neodymium (Nd), and ytterbium (Yb), have been identified in the H band, while yttrium (Y) lines have been identified in the K band. Aims. Due to the scarcity of spectral lines from neutron-capture elements in the NIR, the addition of useful spectral lines from other neutron-capture elements is highly desirable. The aim of this work is to identify and characterise a spectral line suitable for abundance determination from the most commonly used s-process element, namely barium. Methods. We observed the NIR spectra of 37 M giants in the solar neighbourhood at high spectral resolution and with a high signal-to-noise ratio using the IGRINS spectrometer on the GEMINI South telescope. The full H- and K-bands were recorded simultaneously at R = 45 000. Using a manual spectral synthesis method, we determined the fundamental stellar parameters for these stars and derived the barium abundance from the Ba line (6s5d 3D2 → 6s6p 3P2o) at λair = 23 253.56 Å in the K band. Results. We demonstrate that the Ba line in the K band at 2.33 μm (λ23 253.56) is useful for abundance analyses from the spectra of M giants. The line becomes progressively weaker at higher temperatures and is only useful in M giants and the coolest K giants at supersolar metallicities. Conclusions. We can now add Ba to the trends of the heavy elements Cu, Zn, Y, Ce, Nd, and Yb, which can be retrieved from high-resolution H- and K-band spectra. This opens up the study of nucleosynthetic channels, including the s-process and the r-process, in dust-obscured populations. Thus, these elements can be studied for heavily dust-obscured regions of the Galaxy, such as the Galactic centre. [ABSTRACT FROM AUTHOR]

© 2015 American Academy of Allergy, Asthma & Immunology. Background: Earlier studies reported that many patients were frequently hospitalized for asthma exacerbation. However, there have been no recent multicenter studies to characterize this patient population with high morbidity and health care utilization. Objective: To examine the proportion and characteristics of children and adults with frequent hospitalizations for asthma exacerbation. Methods: A multicenter chart review study of patients aged 2 to 54 years who were hospitalized for asthma exacerbation at 1 of 25 hospitals across 18 US states during the period 2012 to 2013 was carried out. The primary outcome was frequency of hospitalizations for asthma exacerbation in the past year (including the index hospitalization). Results: The cohort included 369 children (aged 2-17 years) and 555 adults (aged 18-54 years) hospitalized for asthma exacerbation. Over the 12-month period, 36% of the children and 42% of the adults had 2 or more (frequent) hospitalizations for asthma exacerbation. Among patients with frequent hospitalizations, guideline-recommended outpatient management was suboptimal. For example, among adults, 32% were not on inhaled corticosteroids at the time of index hospitalization and 75% had no evidence of a previous evaluation by an asthma specialist. At hospital discharge, among adults with frequent hospitalizations who had used no controller medications previously, 37% were not prescribed inhaled corticosteroids. Likewise, during a 3-month postdischarge period, 64% of the adults with frequent hospitalizations were not referred to an asthma specialist. Although the proportion of patients who did not receive these guideline-recommended outpatient care appeared higher in adults, these preventive measures were still underutilized in children; for example, 38% of the children with frequent hospitalizations were not referred to asthma specialist after the index hospitalization. Conclusions: This multicenter study of US patients hospitalized with asthma exacerbation demonstrated a disturbingly high proportion of patients with frequent hospitalizations and ongoing evidence of suboptimal longitudinal asthma care.

Aims. The aim of this study is to provide radiative data for neutral and singly ionised silicon, in particular for the first experimental oscillator strengths for near-infrared Si I lines. In addition, we aim to perform atomic structure calculations both for neutral and singly ionised silicon while including lines from highly excited levels. Methods. We performed large-scale atomic structure calculations with the relativistic multiconfiguration Dirac-Hartree-Fock method using the GRASP2K package to determine log(푔ƒ) values of Si I and Si II lines, taking into account valence-valence and core-valence electron correlation. In addition, we derived oscillator strengths of near-infrared Si I lines by combining the experimental branching fractions with radiative lifetimes from our calculations. The silicon plasma was obtained from a hollow cathode discharge lamp, and the intensity-calibrated high-resolution spectra between 1037 and 2655 nm were recorded by a Fourier transform spectrometer. Results. We provide an extensive set of accurate experimental and theoretical log(푔ƒ) values. For the first time, we derived 17 log(푔ƒ) values of Si I lines in the infrared from experimental measurements. We report data for 1500 Si I lines and 500 Si II lines. The experimental uncertainties of our ƒ-values vary between 5% for the strong lines and 25% for the weak lines. The theoretical log(푔ƒ) values for Si I lines in the range 161 nm to 6340 nm agree very well with the experimental values of this study and complete the missing transitions involving levels up to 3s23p7s (61 970 cm−1). In addition, we provide accurate calculated log(푔ƒ) values of Si II lines from the levels up to 3s27f (122 483 cm−1) in the range 81 nm to 7324 nm. [ABSTRACT FROM AUTHOR]

Aims. Accurate atomic data for Ti II are essential for abundance analyses in astronomical objects. The aim of this work is to provide accurate and extensive results of oscillator strengths and lifetimes for Ti II. Methods. The multiconfiguration Dirac–Hartree–Fock and relativistic configuration interaction (RCI) methods, which are implemented in the general-purpose relativistic atomic structure package GRASP2018, were used in the present work. In the final RCI calculations, the transverse-photon (Breit) interaction, the vacuum polarisation, and the self-energy corrections were included. Results. Energy levels and transition data were calculated for the 99 lowest states in Ti II. Calculated excitation energies are found to be in good agreement with experimental data from the Atomic Spectra Database of the National Institute of Standards and Technology based on the study by Huldt et al. Lifetimes and transition data, for example, line strengths, weighted oscillator strengths, and transition probabilities for radiative electric dipole (E1), magnetic dipole (M1), and electric quadrupole (E2) transitions, are given and extensively compared with the results from previous calculations and measurements, when available. The present theoretical results of the oscillator strengths are, overall, in better agreement with values from the experiments than the other theoretical predictions. The computed lifetimes of the odd states are in excellent agreement with the measured lifetimes. Finally, we suggest a relabelling of the 3d2(12D)4py2D3/2o 3 d 2 (2 1 D) 4 p y 2 D 3 / 2 o $ 3d^2(^{1}_{2}D)4p\,y^2D_{3/2}^{o} $ and z2P3/2o z 2 P 3 / 2 o $ z^2P_{3/2}^{o} $ levels. [ABSTRACT FROM AUTHOR]

We discovered Bowen emission arising from a strongly lensed (i.e. with magnification factor μ > 20) source hosted in the Sunburst arc at z  = 2.37. We claim this source is plausibly a transient stellar object and study the unique ultraviolet lines emerging from it. In particular, narrow (σ v  ≃ 40 km s−1) ionization lines of Fe fluoresce after being exposed to Ly α (1216 Å) radiation that pumps selectively their atomic levels. Data from VLT/MUSE, X-Shooter, and ESPRESSO observations (the latter placed at the focus of the four UTs) at increasing spectral resolution of R = 2500, 11 400, and 70 000, respectively, confirm such fluorescent lines are present since at least 3.3 yr (≃1 yr rest frame). Additional Fe forbidden lines have been detected, while C and Si doublets probe an electron density n e ≳ 106 cm−3. Similarities with the spectral features observed in the circumstellar Weigelt blobs of Eta Carinae probing the circumstellar dense gas condensations in radiation-rich conditions are observed. We discuss the physical origin of the transient event, which remains unclear. We expect such transient events (including also supernova or impostors) will be easily recognized with ELTs thanks to high angular resolution provided by adaptive optics and large collecting area, especially in modest (μ < 3) magnification regime. [ABSTRACT FROM AUTHOR]

Context. In the advent of new infrared high-resolution spectrometers, accurate and precise atomic data in the infrared are urgently needed. Identifications, wavelengths, strengths, broadening, and hyper-fine splitting parameters of stellar lines in the near-infrared are in many cases not accurate enough to model observed spectra, and in other cases, these parameters do not even exist. Some stellar features are unidentified. Aims. The aim with this work is to identify a spectral feature at λvac = 1063.891 nm or λair = 1063.600 nm that is visible in spectra of stars of different spectral types that are observed with the GIANO-B spectrometer. Methods. The search for spectral lines to match the unidentified feature in line lists from standard atomic databases was not successful. However, by investigating the original published laboratory data, we were able to identify the feature and solve the problem. To confirm its identification, we modelled the presumed stellar line in the solar intensity spectrum and found an excellent match. Results. We find that the observed spectral feature is a stellar line originating from the 4s′–4p′ transition in S I, and that the reason for its absence in atomic line databases is a neglected air-to-vacuum correction in the original laboratory measurements from 1967 for this line only. From interpolation we determine the laboratory wavelength of the S I line to be λvac = 1063.8908 nm or λair = 1063.5993 nm, and the excitation energy of the upper level to be 9.74978 eV. [ABSTRACT FROM AUTHOR]

We present extensive multiconfiguration Dirac-Hartree-Fock and relativistic configuration interaction calculations including 106 states in doubly ionized silicon (Si III) and 45 states in triply ionized silicon (Si IV), which are important for astrophysical determination of plasma properties in different objects. These calculations represents an important extension and improvement of earlier calculations especially for Si III. The calculations are in good agreement with available experiments for excitation energies, transition properties, and lifetimes. Important deviations from the NIST-database for a selection of perturbed Rydberg series are discussed in detail. [ABSTRACT FROM AUTHOR]

Aims. We have measured and calculated lifetimes of high lying levels in Nb II, and derived absolute transition probabilities by combining the lifetimes with experimental branching fractions. Methods. The lifetimes were measured using time-resolved laser-induced fluorescence in a two-photon and two-step excitation scheme. The branching fractions were measured in intensity calibrated spectra from a hollow cathode discharge, recorded with a Fourier transform spectrometer. The calculations were performed with the relativistic Hartree–Fock method including core polarization. Results. We report experimental lifetimes of 13 levels in the 4d3(4F)5d and 4d3(4F)6s subconfigurations, at an energy around 70 000 cm−1. By combining the lifetimes with experimental branching fractions absolute transition probabilities of 59 lines are derived. The experimental results are compared with calculated values. [ABSTRACT FROM AUTHOR]

Abstract: Aims: To investigate the microbiological quality of imported fresh leaves on retail sale during 2017 with respect to Salmonella, Shiga‐toxin‐producing Escherichia coli (STEC) and levels of E. coli. Methods and Results: Two hundred and seventy‐nine samples of imported edible leaves (69 banana, 77 betel, 118 curry and 15 other types) were tested. Salmonella spp. were confirmed by whole‐genome sequencing and isolated from 44 samples, 26% from curry leaves, 14% from betel and 2·4% from all other leaf types: 80% of all samples contained ≥102, 44% ≥103 and 22% ≥104 CFU of E. coli CFU per g. All samples where Salmonella were detected also yielded ≥20 CFU of E. coli/g. 54 samples were tested for STEC which was detected in six samples and isolated from three: one was identified as STEC O157:H7. Conclusions: This report further highlights an ongoing problem of Salmonella contamination of imported fresh edible leaves. Significance and Impact of the Study: Among all food tested by Public Health England (approximately 11 000 per annum), curry leaves were the herb most commonly contaminated with Salmonella, and betel leaves were the most commonly contaminated ready‐to‐eat food. The high proportion with unsatisfactory E. coli levels and the detection of STEC suggests risks of contamination by multiple enteric pathogens. [ABSTRACT FROM AUTHOR]

The lifetimes of 17 even-parity levels (3d5s, 3d4d, 3d6s and 4p2) in the region 57 743-77 837 cm-1 of singly ionized scandium (Sc II) were measured by two-step timeresolved laser induced fluorescence spectroscopy. Oscillator strengths of 57 lines from these highly excited upper levels were derived using a hollow cathode discharge lamp and a Fourier transform spectrometer. In addition, Hartree-Fock calculations where both the main relativistic and core-polarization effects were taken into account were carried out for both low- and high-excitation levels. There is a good agreement for most of the lines between our calculated branching fractions and the measurements of Lawler & Dakin in the region 9000-45 000 cm-1 for low excitation levels and with our measurements for high excitation levels in the region 23 500-63 100 cm-1. This, in turn, allowed us to combine the calculated branching fractions with the available experimental lifetimes to determine semi-empirical oscillator strengths for a set of 380 E1 transitions in Sc II. These oscillator strengths include the weak lines that were used previously to derive the solar abundance of scandium. The solar abundance of scandium is now estimated to logϵ☉ = 3.04 ± 0.13 using these semi-empirical oscillator strengths to shift the values determined by Scott et al. The new estimated abundance value is in agreement with the meteoritic value (logϵmet = 3.05 ± 0.02) of Lodders, Palme & Gail. [ABSTRACT FROM AUTHOR]

We report new time-resolved laser-induced fluorescence lifetime measurements for 22 highly excited even-parity levels in singly ionized yttrium (Y II). To populate these levels belonging to the configurations 4d6s, 5s6s 4d5d, 5p2, 4d7s and 4d6d, a two-step laser excitation technique was used. Our previous pseudo-relativistic Hartree-Fock model (Biémont et al. 2011) was improved by extending the configuration interaction up to n = 10 to reproduce the new experimental lifetimes. A set of semi-empirical oscillator strengths extended to transitions falling in the spectral range λλ194-3995 nm, depopulating these 22 even-parity levels in Y II, is presented and compared to the values found in the Kurucz's data base (Kurucz 2011). [ABSTRACT FROM AUTHOR]

Aims. This work reports new experimental radiative lifetimes and calculated oscillator strengths for transitions from 3d84d levels of astrophysical interest in singly ionized nickel. Methods. Radiative lifetimes of seven high-lying levels of even parity in Ni II (98 400-100 600 cm-1) have been measured using the time-resolved laser-induced fluorescence method. Two-step photon excitation of ions produced by laser ablation has been utilized to populate the levels. Theoretical calculations of the radiative lifetimes of the measured levels and transition probabilities from these levels are reported. The calculations have been performed using a pseudo-relativistic Hartree-Fock method, taking into account core polarization effects. Results. A new set of transition probabilities and oscillator strengths has been deduced for 477 Ni II transitions of astrophysical interest in the spectral range 194..520 nm depopulating even parity 3d84d levels. The new calculated gf-values are, on the average, about 20% higher than a previous calculation and yield lifetimes within 5% of the experimental values. [ABSTRACT FROM AUTHOR]

This work reports new experimental radiative lifetimes and calculated oscillator strengths for transitions of astrophysical interest in singly ionized cobalt. More precisely, 19 radiative lifetimes in Co+ have been measured with the time-resolved laser-induced fluorescence technique using one- and two-step excitations. Out of these, seven belonging to the high lying 3d7(4F)4d configuration in the energy range 90 697–93 738 cm−1 are new, and the other 12 from the 3d7(4F)4p configuration with energies between 45 972 and 49 328 cm−1 are compared with previous measurements. In addition, a relativistic Hartree–Fock model including core-polarization effects has been employed to compute transition rates. Supported by the good agreement between theory and experiment for the lifetimes, new reliable transition probabilities and oscillator strengths have been deduced for 5080 Co ii transitions in the spectral range 114–8744 nm. [ABSTRACT FROM AUTHOR]

This work reports new experimental radiative lifetimes of six 3d2(3F)5s levels in singly ionized titanium, with an energy around 63 000 cm-1 and four 3d2(3F)4p odd parity levels where we confirm previous investigations. Combining the new 5s lifetimes with branching fractions measured previously by Pickering et al., we report 57 experimental log gf values for transitions from the 5s levels. The lifetime measurements are performed using time-resolved laser-induced fluorescence on ions produced by laser ablation. One- and two-step photon excitation is employed to reach the 4p and 5s levels, respectively. Theoretical calculations of the radiative lifetimes of the measured levels as well as of oscillator strengths for 3336 transitions from these levels are reported. The calculations are carried out by a pseudorelativistic Hartree-Fock method taking into account core-polarization effects. The theoretical results are in a good agreement with the experiments and are needed for accurate abundance determinations in astronomical objects. [ABSTRACT FROM AUTHOR]