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We used a survey to characterize contemporary infection prevention and antibiotic stewardship program practices across 64 healthcare facilities, and we compared these findings to those of a similar 2013 survey. Notable findings include decreased frequency of active surveillance for methicillin-resistant Staphylococcus aureus, frequent active surveillance for carbapenem-resistant Enterobacteriaceae, and increased support for antibiotic stewardship programs.
To ascertain opinions regarding etiology and preventability of hospital-onset bacteremia and fungemia (HOB) and perspectives on HOB as a potential outcome measure reflecting quality of infection prevention and hospital care.
Hospital epidemiologists and infection preventionist members of the Society for Healthcare Epidemiology of America (SHEA) Research Network.
A web-based, multiple-choice survey was administered via the SHEA Research Network to 133 hospitals.
A total of 89 surveys were completed (67% response rate). Overall, 60% of respondents defined HOB as a positive blood culture on or after hospital day 3. Central line-associated bloodstream infections and intra-abdominal infections were perceived as the most frequent etiologies. Moreover, 61% thought that most HOB events are preventable, and 54% viewed HOB as a measure reflecting a hospital’s quality of care. Also, 29% of respondents’ hospitals already collect HOB data for internal purposes. Given a choice to publicly report central-line–associated bloodstream infections (CLABSIs) and/or HOB, 57% favored reporting either HOB alone (22%) or in addition to CLABSI (35%) and 34% favored CLABSI alone.
Among the majority of SHEA Research Network respondents, HOB is perceived as preventable, reflective of quality of care, and potentially acceptable as a publicly reported quality metric. Further studies on HOB are needed, including validation as a quality measure, assessment of risk adjustment, and formation of evidence-based bundles and toolkits to facilitate measurement and improvement of HOB rates.
People with psychotic disorders face impairments in their global functioning and their quality of life (QoL). The relationship between the two outcomes has not been systematically investigated. Through a systematic review, we aim to explore the presence and extent of associations between global functioning and QoL and establish whether associations depend on the instruments employed.
In May 2016, ten electronic databases were searched using a two-phase process to identify articles in which associations between global functioning and QoL were assessed. Basic descriptive data and correlation coefficients between global functioning and QoL instruments were extracted, with the strength of the correlation assessed according to the specifications of Cohen 1988. Results were reported with reference to the Meta-analysis of Observational Studies in Epidemiology guidelines and PRISMA standards. A narrative synthesis was performed due to heterogeneity in methodological approaches.
Of an initial 15 183 non-duplicate articles identified, 756 were deemed potentially relevant, with 40 studies encompassing 42 articles included. Fourteen instruments for measuring global functioning and 22 instruments for measuring QoL were used. Twenty-nine articles reported linear associations while 19 assessed QoL predictors. Correlations between overall scores varied in strength, primarily dependent on the QoL instrument employed, and whether QoL was objectively or subjectively assessed. Correlations observed for objective QoL measures were consistently larger than those observed for subjective measures, as were correlations for an interviewer than self-assessed QoL. When correlations were assessed by domains of QoL, the highest correlations were found for social domains of QoL, for which most correlations were moderate or higher. Global functioning consistently predicted overall QoL as did depressive and negative symptoms.
This review is the first to explore the extent of associations between global functioning and QoL in people with psychotic disorders. We consistently found a positive association between global functioning and QoL. The strength of the association was dependent on the QoL instrument employed. QoL domains strongly associated with global functioning were highlighted. The review illustrates the extensive array of instruments used for the assessment of QoL and to a lesser extent global functioning in people with psychotic disorders and provides a framework to understand the different findings reported in the literature. The findings can also inform the future choice of instruments by researchers and/or clinicians. The observed associations reassure that interventions for improving global functioning will have a positive impact on the QoL of people living with a psychotic disorder.
The Pediatric Heart Network designed a career development award to train the next generation of clinician scientists in paediatric-cardiology-related research, a historically underfunded area. We sought to identify the strengths/weaknesses of the programme and describe the scholars’ academic achievements and the network’s return on investment.
Survey questions designed to evaluate the programme were sent to applicants – 13 funded and 19 unfunded applicants – and 20 mentors and/or principal investigators. Response distributions were calculated. χ2 tests of association assessed differences in ratings of the application/selection processes among funded scholars, unfunded applicants, and mentors/principal investigators. Scholars reported post-funding academic achievements.
Survey response rates were 88% for applicants and 100% for mentor/principal investigators. Clarity and fairness of the review were rated as “clear/fair” or “very clear/very fair” by 98% of respondents, but the responses varied among funded scholars, unfunded applicants, and mentors/principal investigators (clarity χ2=10.85, p=0.03; fairness χ2=16.97, p=0.002). Nearly half of the unfunded applicants rated feedback as “not useful” (47%). “Expanding their collaborative network” and “increasing publication potential” were the highest-rated benefits for scholars. Mentors/principal investigators found the programme “very” valuable for the scholars (100%) and the network (75%). The 13 scholars were first/senior authors for 97 abstracts and 109 manuscripts, served on 22 Pediatric Heart Network committees, and were awarded $9,673,660 in subsequent extramural funding for a return of ~$10 for every scholar dollar spent.
Overall, patient satisfaction with the Scholar Award was high and scholars met many academic markers of success. Despite this, programme challenges were identified and improvement strategies were developed.
The Murchison Widefield Array (MWA), located in Western Australia, is one of the low-frequency precursors of the international Square Kilometre Array (SKA) project. In addition to pursuing its own ambitious science programme, it is also a testbed for wide range of future SKA activities ranging from hardware, software to data analysis. The key science programmes for the MWA and SKA require very high dynamic ranges, which challenges calibration and imaging systems. Correct calibration of the instrument and accurate measurements of source flux densities and polarisations require precise characterisation of the telescope’s primary beam. Recent results from the MWA GaLactic Extragalactic All-sky Murchison Widefield Array (GLEAM) survey show that the previously implemented Average Embedded Element (AEE) model still leaves residual polarisations errors of up to 10–20% in Stokes Q. We present a new simulation-based Full Embedded Element (FEE) model which is the most rigorous realisation yet of the MWA’s primary beam model. It enables efficient calculation of the MWA beam response in arbitrary directions without necessity of spatial interpolation. In the new model, every dipole in the MWA tile (4 × 4 bow-tie dipoles) is simulated separately, taking into account all mutual coupling, ground screen, and soil effects, and therefore accounts for the different properties of the individual dipoles within a tile. We have applied the FEE beam model to GLEAM observations at 200–231 MHz and used false Stokes parameter leakage as a metric to compare the models. We have determined that the FEE model reduced the magnitude and declination-dependent behaviour of false polarisation in Stokes Q and V while retaining low levels of false polarisation in Stokes U.
Rhinanthus minor is a facultative hemiparasitic plant of the Scrophulariaceae family native to the British Isles. It is typically found in meadows associated with a high floristic diversity, but it can also be found in pasture, where it is susceptible to heavy grazing. Containing the iridoid glycoside rhinanthin (C29H52O20), R. minor is strongly suspected of being poisonous, but it is not clear how harmful this is to livestock (Long 1924). Through parasitism, particularly of the grasses, R. minor is also associated with a loss of grazing. Consequently, the presence of R. minor in a sward is often viewed negatively. However, through reductions in productivity of grasses, R. minor may have a role in the restoration of species-rich grasslands. As a result, the probability of cattle consuming R. minor might be expected to increase. This paper aims to evaluate the degradation of R. minor and discusses the implications of R. minor inclusion in the diet.
As part of “Rumen-Up”, an EU Framework 5 project, a total of 500 plants and plant extracts were screened in vitro for their effect on general rumen fermentation parameters, in particular their ability to influence microbial protein production, protozoal numbers, methane production, bloat and acidosis. Many of the plants investigated were found to have potentially beneficial effects with respect to ruminant production. The activities of 25 plants were patented, including two that The University of Reading identified as maintaining a significantly higher fermentation medium pH - common lettuce (Lactuca sativa) and stinging nettle ( Urtica dioica) with the aim that these plants (or their derivatives) would be incorporated as feed supplements to reduce the incidence of rumen acidosis. The results reported here are from an in vitro dose titration study conducted to identify possible dietary inclusion levels prior to conducting a large-scale animal production study.
As part of the EU Framework 5 project “Rumen-Up”, plants were screened for their effect on the in vitro fermentation medium pH. Common lettuce (Lactuca sativa) and stinging nettle (Urtica dioica) were identified as having a positive effect, maintaining a higher pH when fermented with wheat over 48 hours. It was considered that the rumen microflora may adapt to the inclusion of either plant in the diet, leading to negation of the effect, and therefore reducing the opportunities for use as a supplement to prevent acidosis. This study was designed to investigate the persistency of the anti-acidosis effect using the Rumen Simulation Technique (RUSITEC), together with batch in vitro fermentation using inoculum harvested from RUSITEC.
The immediate postweaning period in pigs is often characterised by a reduced and variable food intake, digestive disorders and poor growth and development. Historically such effects were reduced by the use of in-feed antibiotic growth promoters (AGPs), copper sulphate and zinc oxide to enhance the efficiency of feed conversion and hence maximise nutrient capture. However from January 2006 the routine use of in-feed AGPs was banned and, due to concern over environmental pollution, levels of inclusion of heavy metals are limited by regulation and likely to be further reduced in the future. Weaning pigs at a later age has been suggested as an approach to reduce the potentially negative effects of the AGP ban on the national herd. The objective of the AGEWEAN programme of research was to investigate the effects of weaning age (4, 6 and 8 weeks) in both an indoor and outdoor lactation environment on the biological and economic efficiency of production where diets contain no AGPs and lower levels of copper (<25ppm added) and zinc (<100ppm added).
The buffered incubation medium used in many in vitro ruminant feedstuff degradation assays is essentially that described by Goering and Van Soest . Hungate  suggested that the actual composition of the inorganic salts in the medium was not vital as long as it provided sufficient buffering capacity and was of a similar osmotic potential to rumen fluid, while Tilley and Terry  argued that sufficient trace elements and “growth stimulants” would be provided by the rumen fluid inoculum or substrate and that fermentation gas would maintain anaerobic conditions. The divergent composition of these media reflects that the microbiologists were attempting to create a “habitat-simulating” media [Hungate, 1966] while nutritionists were using a slightly modified rumen environment in vitro to permit microbial degradation of feedstuffs. The objectives of this study were to identify whether reduction of media is necessary prior to use, and to develop a nitrogen free media which could be used for determining the effects of nitrogen supplementation on the fermentation of feedstuffs.
Many reports indicate that mixed microbial populations preferentially incorporate peptides or NH4+ rather than free amino acids [e.g. Pittman and Bryant, 1964]. As part of a study to evaluate a novel encapsulation process, an in vitro technique to examine amino acid degradation was developed using a compliment test based on the Reading Pressure Technique [Mauricio et al., 1999]. In this methodology, the ability of rumen microorganisms to ferment a pure carbohydrate substrate in a nitrogen-deficient medium was significantly correlated to the level of available nitrogen. It therefore followed that fermentation gas release could be used as a simple technique to examine and quantify nitrogen availability. The study described compared three nitrogen sources offered either alone or in combination.
Escherichia coli O157 are zoonotic bacteria for which cattle are an important reservoir. Prevalence estimates for E. coli O157 in British cattle for human consumption are over 10 years old. A new baseline is needed to inform current human health risk. The British E. coli O157 in Cattle Study (BECS) ran between September 2014 and November 2015 on 270 farms across Scotland and England & Wales. This is the first study to be conducted contemporaneously across Great Britain, thus enabling comparison between Scotland and England & Wales. Herd-level prevalence estimates for E. coli O157 did not differ significantly for Scotland (0·236, 95% CI 0·166–0·325) and England & Wales (0·213, 95% CI 0·156–0·283) (P = 0·65). The majority of isolates were verocytotoxin positive. A higher proportion of samples from Scotland were in the super-shedder category, though there was no difference between the surveys in the likelihood of a positive farm having at least one super-shedder sample. E. coli O157 continues to be common in British beef cattle, reaffirming public health policy that contact with cattle and their environments is a potential infection source.
The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target fields. In this paper, we develop a model for the compact foreground sources in one of the target fields of the MWA’s EoR key science experiment: the ‘EoR1’ field. The model is based on both the MWA’s GLEAM survey and GMRT 150 MHz data from the TGSS survey, the latter providing higher angular resolution and better astrometric accuracy for compact sources than is available from the MWA alone. The model contains 5 049 sources, some of which have complicated morphology in MWA data, Fornax A being the most complex. The higher resolution data show that 13% of sources that appear point-like to the MWA have complicated morphology such as double and quad structure, with a typical separation of 33 arcsec. We derive an analytic expression for the error introduced into the EoR two-dimensional power spectrum due to peeling close double sources as single point sources and show that for the measured source properties, the error in the power spectrum is confined to high k⊥ modes that do not affect the overall result for the large-scale cosmological signal of interest. The brightest 10 mis-modelled sources in the field contribute 90% of the power bias in the data, suggesting that it is most critical to improve the models of the brightest sources. With this hybrid model, we reprocess data from the EoR1 field and show a maximum of 8% improved calibration accuracy and a factor of two reduction in residual power in k-space from peeling these sources. Implications for future EoR experiments including the SKA are discussed in relation to the improvements obtained.
Measures of the equivalent widths of major stellar features in the visible and UV regions of a sample of the LMC supergiants whose types range from 05 to A1 have been derived. Their low resolution UV spectra were obtained with the IUE and complemented in the visual with spectra from ESO 3.6 m and SAAO 1.95 m telescopes. The methods used are entirely numerical and as far as possible free from subjective estimates. The data for the LMC members have been compared with those obtained for their Galactic counterparts. The variation of CIV 1550 Å and Si IV 1400 Å absorptions with spectral type has been investigated. It may be that the intensity of HeI lines is smaller for the middle and late B supergiant members of the LMC as compared with those Galactic standards, otherwise there is no systematic difference within the observational errors between the Galactic and LMC supergiants in the strengths of the principal stellar features observed in the visible as a function of spectral type. Galactic 0 and early B supergiants have greater equivalent widths of Si IV λ 1400 and C IV λ 1550 absorptions than the LMC supergiants of similar spectral types, confirming earlier observations of Hutchings.
We present low-frequency spectral energy distributions of 60 known radio pulsars observed with the Murchison Widefield Array telescope. We searched the GaLactic and Extragalactic All-sky Murchison Widefield Array survey images for 200-MHz continuum radio emission at the position of all pulsars in the Australia Telescope National Facility (ATNF) pulsar catalogue. For the 60 confirmed detections, we have measured flux densities in 20 × 8 MHz bands between 72 and 231 MHz. We compare our results to existing measurements and show that the Murchison Widefield Array flux densities are in good agreement.
We estimate spatial gradients in the ionosphere using the Global Positioning System and GLONASS (Russian global navigation system) observations, utilising data from multiple Global Positioning System stations in the vicinity of Murchison Radio-astronomy Observatory. In previous work, the ionosphere was characterised using a single-station to model the ionosphere as a single layer of fixed height and this was compared with ionospheric data derived from radio astronomy observations obtained from the Murchison Widefield Array. Having made improvements to our data quality (via cycle slip detection and repair) and incorporating data from the GLONASS system, we now present a multi-station approach. These two developments significantly improve our modelling of the ionosphere. We also explore the effects of a variable-height model. We conclude that modelling the small-scale features in the ionosphere that have been observed with the MWA will require a much denser network of Global Navigation Satellite System stations than is currently available at the Murchison Radio-astronomy Observatory.
Evidence has accumulated that implicates childhood trauma in the aetiology of psychosis, but our understanding of the putative psychological processes and mechanisms through which childhood trauma impacts on individuals and contributes to the development of psychosis remains limited. We aimed to investigate whether stress sensitivity and threat anticipation underlie the association between childhood abuse and psychosis.
We used the Experience Sampling Method to measure stress, threat anticipation, negative affect, and psychotic experiences in 50 first-episode psychosis (FEP) patients, 44 At-Risk Mental State (ARMS) participants, and 52 controls. Childhood abuse was assessed using the Childhood Trauma Questionnaire.
Associations of minor socio-environmental stress in daily life with negative affect and psychotic experiences were modified by sexual abuse and group (all pFWE < 0.05). While there was strong evidence that these associations were greater in FEP exposed to high levels of sexual abuse, and some evidence of greater associations in ARMS exposed to high levels of sexual abuse, controls exposed to high levels of sexual abuse were more resilient and reported less intense negative emotional reactions to socio-environmental stress. A similar pattern was evident for threat anticipation.
Elevated sensitivity and lack of resilience to socio-environmental stress and enhanced threat anticipation in daily life may be important psychological processes underlying the association between childhood sexual abuse and psychosis.
We have compiled a catalogue of H ii regions detected with the Murchison Widefield Array between 72 and 231 MHz. The multiple frequency bands provided by the Murchison Widefield Array allow us identify the characteristic spectrum generated by the thermal Bremsstrahlung process in H ii regions. We detect 306 H ii regions between 260° < l < 340° and report on the positions, sizes, peak, integrated flux density, and spectral indices of these H ii regions. By identifying the point at which H ii regions transition from the optically thin to thick regime, we derive the physical properties including the electron density, ionised gas mass, and ionising photon flux, towards 61 H ii regions. This catalogue of H ii regions represents the most extensive and uniform low frequency survey of H ii regions in the Galaxy to date.
Des classifications spectrales et des mesures photométriques ont été faites dans de nombreux Observatoires.
La classification à un seul paramètre, comme celle de Harvard, a été remplacée dans la plupart des cas par une classification bidimensionelle. La classification simplifiée est réservée aux étoiles faibles. Les classifications dans le système MK ont été faites dans de nombreux Observatoires et nous signalons les importantes listes d’Abastumani.
De nombreux astronomes ont recherché les étoiles riches ou pauvres en métaux, ce qui est l’amorce des classifications à trois paramètres. Des listes d’étoiles Am et Ap ont été publiées.