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We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep continuum weak lensing and low-redshift spectroscopic HI galaxy survey over 5 000 deg2; a wide and deep continuum galaxy and HI intensity mapping (IM) survey over 20 000 deg2 from
$z = 0.35$
to 3; and a deep, high-redshift HI IM survey over 100 deg2 from
$z = 3$
to 6. Taken together, these surveys will achieve an array of important scientific goals: measuring the equation of state of dark energy out to
$z \sim 3$
with percent-level precision measurements of the cosmic expansion rate; constraining possible deviations from General Relativity on cosmological scales by measuring the growth rate of structure through multiple independent methods; mapping the structure of the Universe on the largest accessible scales, thus constraining fundamental properties such as isotropy, homogeneity, and non-Gaussianity; and measuring the HI density and bias out to
$z = 6$
. These surveys will also provide highly complementary clustering and weak lensing measurements that have independent systematic uncertainties to those of optical and near-infrared (NIR) surveys like Euclid, LSST, and WFIRST leading to a multitude of synergies that can improve constraints significantly beyond what optical or radio surveys can achieve on their own. This document, the 2018 Red Book, provides reference technical specifications, cosmological parameter forecasts, and an overview of relevant systematic effects for the three key surveys and will be regularly updated by the Cosmology Science Working Group in the run up to start of operations and the Key Science Programme of SKA1.
The mechanism through which developmental programming of offspring overweight/obesity following in utero exposure to maternal overweight/obesity operates is unknown but may operate through biologic pathways involving offspring anthropometry at birth. Thus, we sought to examine to what extent the association between in utero exposure to maternal overweight/obesity and childhood overweight/obesity is mediated by birth anthropometry. Analyses were conducted on a retrospective cohort with data obtained from one hospital system. A natural effects model framework was used to estimate the natural direct effect and natural indirect effect of birth anthropometry (weight, length, head circumference, ponderal index, and small-for-gestational age [SGA] or large-for-gestational age [LGA]) for the association between pre-pregnancy maternal body mass index (BMI) category (overweight/obese vs normal weight) and offspring overweight/obesity in childhood. Models were adjusted for maternal and child socio-demographics. Three thousand nine hundred and fifty mother–child dyads were included in analyses (1467 [57.8%] of mothers and 913 [34.4%] of children were overweight/obese). Results suggest that a small percentage of the effect of maternal pre-pregnancy BMI overweight/obesity on offspring overweight/obesity operated through offspring anthropometry at birth (weight: 15.5%, length: 5.2%, head circumference: 8.5%, ponderal index: 2.2%, SGA: 2.9%, and LGA: 4.2%). There was a small increase in the percentage mediated when gestational diabetes or hypertensive disorders were added to the models. Our study suggests that some measures of birth anthropometry mediate the association between maternal pre-pregnancy overweight/obesity and offspring overweight/obesity in childhood and that the size of this mediated effect is small.
The science of studying diamond inclusions for understanding Earth history has developed significantly over the past decades, with new instrumentation and techniques applied to diamond sample archives revealing the stories contained within diamond inclusions. This chapter reviews what diamonds can tell us about the deep carbon cycle over the course of Earth’s history. It reviews how the geochemistry of diamonds and their inclusions inform us about the deep carbon cycle, the origin of the diamonds in Earth’s mantle, and the evolution of diamonds through time.
Identifying risk factors of individuals in a clinical-high-risk state for psychosis are vital to prevention and early intervention efforts. Among prodromal abnormalities, cognitive functioning has shown intermediate levels of impairment in CHR relative to first-episode psychosis and healthy controls, highlighting a potential role as a risk factor for transition to psychosis and other negative clinical outcomes. The current study used the AX-CPT, a brief 15-min computerized task, to determine whether cognitive control impairments in CHR at baseline could predict clinical status at 12-month follow-up.
Baseline AX-CPT data were obtained from 117 CHR individuals participating in two studies, the Early Detection, Intervention, and Prevention of Psychosis Program (EDIPPP) and the Understanding Early Psychosis Programs (EP) and used to predict clinical status at 12-month follow-up. At 12 months, 19 individuals converted to a first episode of psychosis (CHR-C), 52 remitted (CHR-R), and 46 had persistent sub-threshold symptoms (CHR-P). Binary logistic regression and multinomial logistic regression were used to test prediction models.
Baseline AX-CPT performance (d-prime context) was less impaired in CHR-R compared to CHR-P and CHR-C patient groups. AX-CPT predictive validity was robust (0.723) for discriminating converters v. non-converters, and even greater (0.771) when predicting CHR three subgroups.
These longitudinal outcome data indicate that cognitive control deficits as measured by AX-CPT d-prime context are a strong predictor of clinical outcome in CHR individuals. The AX-CPT is brief, easily implemented and cost-effective measure that may be valuable for large-scale prediction efforts.
Schizophrenia is associated with robust hippocampal volume deficits but subregion volume deficits, their associations with cognition, and contributing genes remain to be determined.
Hippocampal formation (HF) subregion volumes were obtained using FreeSurfer 6.0 from individuals with schizophrenia (n = 176, mean age ± s.d. = 39.0 ± 11.5, 132 males) and healthy volunteers (n = 173, mean age ± s.d. = 37.6 ± 11.3, 123 males) with similar mean age, gender, handedness, and race distributions. Relationships between the HF subregion volume with the largest between group difference, neuropsychological performance, and single-nucleotide polymorphisms were assessed.
This study found a significant group by region interaction on hippocampal subregion volumes. Compared to healthy volunteers, individuals with schizophrenia had significantly smaller dentate gyrus (DG) (Cohen's d = −0.57), Cornu Ammonis (CA) 4, molecular layer of the hippocampus, hippocampal tail, and CA 1 volumes, when statistically controlling for intracranial volume; DG (d = −0.43) and CA 4 volumes remained significantly smaller when statistically controlling for mean hippocampal volume. DG volume showed the largest between group difference and significant positive associations with visual memory and speed of processing in the overall sample. Genome-wide association analysis with DG volume as the quantitative phenotype identified rs56055643 (β = 10.8, p < 5 × 10−8, 95% CI 7.0–14.5) on chromosome 3 in high linkage disequilibrium with MOBP. Gene-based analyses identified associations between SLC25A38 and RPSA and DG volume.
This study suggests that DG dysfunction is fundamentally involved in schizophrenia pathophysiology, that it may contribute to cognitive abnormalities in schizophrenia, and that underlying biological mechanisms may involve contributions from MOBP, SLC25A38, and RPSA.
What impact do local candidates have on elections in single member district plurality electoral systems? We provide new evidence using data from a large election study carried out during the 2015 Canadian federal election. We improve on the measurement of local candidate effects by asking over 20,000 survey respondents to rate the candidates in their constituency directly. We present three estimates. We find that when all voters are considered together, local candidate evaluations are decisive for approximately 4 per cent of voters. Second, these evaluations are decisive for the outcome of 10 per cent of constituency contests. Third, when models are estimated for each constituency, we find significant evaluation effects for 14 per cent of candidates.
To examine associations between availability of fast-food restaurants and convenience stores in the home and school neighbourhoods, considered separately and together, and adolescents’ fast-food and sugar-sweetened beverage (SSB) intakes.
Cross-sectional observational study.
East London, UK.
Adolescents (n 3089; aged 13–15 years) from the Olympic Regeneration in East London (ORiEL) Study self-reported their weekly frequency of fast-food and SSB consumption. We used food business addresses collected from local authority registers to derive absolute (counts) and relative (proportions) exposure measures to fast-food restaurants and convenience stores within 800 m from home, school, and home and school combined. Associations between absolute and relative measures of the food environment and fast-food and SSB intakes were assessed using Poisson regression models with robust standard errors.
Absolute exposure to fast-food restaurants or convenience stores in the home, school, or combined home and school neighbourhoods was not associated with any of the outcomes. High SSB intake was associated with relative exposure to convenience stores in the residential neighbourhood (risk ratio=1·45; 95 % CI 1·08, 1·96) and in the home and school neighbourhoods combined (risk ratio=1·69; 95 % CI 1·11, 2·57).
We found no evidence of an association between absolute exposure to fast-food restaurants and convenience stores around home and school and adolescents’ fast-food and SSB intakes. Relative exposure, which measures the local diversity of the neighbourhood food environment, was positively associated with SSB intake. Relative measures of the food environment may better capture the environmental risks for poor diet than absolute measures.
The present study sought to explicate the time-course of posttraumatic stress (PTS)-related attentional bias to threat (ABT) by examining differences in attention bias variability (ABV; a measure which accounts for the temporal dynamics of ABT). A dot-probe task with four presentation durations was used to capture both subliminal and supraliminal stages of processing. Task stimuli consisted of neutral and threat images. Attentional control (AC) was examined as a moderator of the relationship between PTSD and ABV. At an experimental session, participants (PTSD = 11, trauma control = 18) completed questionnaires, a modified dot-probe task, and a stimulus-response task measuring AC. Individuals in the PTSD group exhibited greater ABV compared to trauma control participants. AC moderated this relationship, with participants with PTSD and poor AC exhibiting significantly greater ABV than trauma-exposed control participants with poor AC. These effects remained significant after accounting for traditionally calculated ABT scores and variability on trials for which only neutral stimuli were present, thus ensuring that the observed effects were specific to the presence of threat stimuli and not merely a function of general variability in response times. Findings implicate AC as a buffering mechanism against threat-related attentional dyscontrol among those with PTSD. Clinical implications will be discussed.
(See the commentary by Van Schooneveld and Rupp, on pages1100–1102.)
Although prior authorization and prospective audit with feedback are both effective antimicrobial stewardship program (ASP) strategies, the relative impact of these approaches remains unclear. We compared these core ASP strategies at an academic medical center.
We compared antimicrobial use during the 24 months before and after implementation of an ASP strategy change. The ASP used prior authorization alone during the preintervention period, June 2007 through May 2009. In June 2009, many antimicrobials were unrestricted and prospective audit was implemented for cefepime, piperacillin/tazobactam, and vancomycin, marking the start of the postintervention period, July 2009 through June 2011. All adult inpatients who received more than or equal to 1 dose of an antimicrobial were included. The primary end point was antimicrobial consumption in days of therapy per 1,000 patient-days (DOT/1,000-PD). Secondary end points included length of stay (LOS).
In total, 55,336 patients were included (29,660 preintervention and 25,676 postintervention). During the preintervention period, both total systemic antimicrobial use (−9.75 DOT/1,000-PD per month) and broad-spectrum anti-gram-negative antimicrobial use (−4.00 DOT/1,000-PD) declined. After the introduction of prospective audit with feedback, however, both total antimicrobial use (+9.65 DOT/1,000-PD per month; P < .001) and broad-spectrum anti-gram-negative antimicrobial use (+4.80 DOT/1,000-PD per month; P < .001) increased significantly. Use of cefepime and piperacillin/tazobactam both significantly increased after the intervention (P = .03). Hospital LOS and LOS after first antimicrobial dose also significantly increased after the intervention (P = .016 and .004, respectively).
Significant increases in antimicrobial consumption and LOS were observed after the change in ASP strategy.
Infect Control Hosp Epidemiol 2014;35(9):1092-1099
Public disclosure of industry payments to physicians is one way to address financial conflicts of interest in medicine. As part of the Patient Protection and Affordable Care Act, the Physician Payment Sunshine Act (PPSA) requires pharmaceutical, medical device, and biologics manufacturers who have at least one product reimbursed by Medicare or Medicaid to disclose payments to physicians and teaching hospitals on a public website starting in 2014. The physician payment data will contain individual physician names, monetary values, and specific products connected to payments.
According to the Final Regulations issued by the Centers for Medicare and Medicaid Services (CMS) in February 2013, the law will make transparent the extent and nature of relationships between physicians, teaching hospitals, and manufacturers.