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We present a broad study of linear, clustered, noble gas puffs irradiated with the frequency doubled (527 nm) Titan laser at Lawrence Livermore National Laboratory. Pure Ar, Kr, and Xe clustered gas puffs, as well as two mixed-gas puffs consisting of KrAr and XeKrAr gases, make up the targets. Characterization experiments to determine gas-puff density show that varying the experimental parameter gas-delay timing (the delay between gas puff initialization and laser-gas-puff interaction) provides a simple control over the gas-puff density. X-ray emission (>1.4 keV) is studied as a function of gas composition, density, and delay timing. Xe gas puffs produce the strongest peak radiation in the several keV spectral region. The emitted radiation was found to be anisotropic, with smaller X-ray flux observed in the direction perpendicular to both laser beam propagation and polarization directions. The degree of anisotropy is independent of gas target type but increases with photon energy. X-ray spectroscopic measurements estimate plasma parameters and highlight their difference with previous studies. Electron beams with energy in excess of 72 keV are present in the noble gas-puff plasmas and results indicate that Ar plays a key role in their production. A drastic increase in harder X-ray emissions (X-ray flash effect) and multi-MeV electron-beam generation from Xe gas-puff plasma occurred when the laser beam was focused on the front edge of the linear gas puff.
Improving quality of life (QOL) for people with dementia is a priority. In care homes, we often rely on proxy ratings from staff and family but we do not know if, or how, they differ in care homes.
We compared 1056 pairs of staff and family DEMQOL-Proxy ratings from 86 care homes across England. We explored factors associated with ratings quantitatively using multilevel modelling and, qualitatively, through thematic analysis of 12 staff and 12 relative interviews.
Staff and family ratings were weakly correlated (ρs = 0.35). Median staff scores were higher than family's (104 v. 101; p < 0.001). Family were more likely than staff to rate resident QOL as ‘Poor’ (χ2 = 55.91, p < 0.001). Staff and family rated QOL higher when residents had fewer neuropsychiatric symptoms and severe dementia. Staff rated QOL higher in homes with lower staff:resident ratios and when staff were native English speakers. Family rated QOL higher when the resident had spent longer living in the care home and was a native English. Spouses rated residents’ QOL higher than other relatives. Qualitative results suggest differences arise because staff felt good care provided high QOL but families compared the present to the past. Family judgements centre on loss and are complicated by decisions about care home placement and their understandings of dementia.
Proxy reports differ systematically between staff and family. Reports are influenced by the rater:staff and family may conceptualise QOL differently.
Major depressive disorder (MDD) is a highly heterogeneous condition in terms of symptom presentation and, likely, underlying pathophysiology. Accordingly, it is possible that only certain individuals with MDD are well-suited to antidepressants. A potentially fruitful approach to parsing this heterogeneity is to focus on promising endophenotypes of depression, such as neuroticism, anhedonia, and cognitive control deficits.
Within an 8-week multisite trial of sertraline v. placebo for depressed adults (n = 216), we examined whether the combination of machine learning with a Personalized Advantage Index (PAI) can generate individualized treatment recommendations on the basis of endophenotype profiles coupled with clinical and demographic characteristics.
Five pre-treatment variables moderated treatment response. Higher depression severity and neuroticism, older age, less impairment in cognitive control, and being employed were each associated with better outcomes to sertraline than placebo. Across 1000 iterations of a 10-fold cross-validation, the PAI model predicted that 31% of the sample would exhibit a clinically meaningful advantage [post-treatment Hamilton Rating Scale for Depression (HRSD) difference ⩾3] with sertraline relative to placebo. Although there were no overall outcome differences between treatment groups (d = 0.15), those identified as optimally suited to sertraline at pre-treatment had better week 8 HRSD scores if randomized to sertraline (10.7) than placebo (14.7) (d = 0.58).
A subset of MDD patients optimally suited to sertraline can be identified on the basis of pre-treatment characteristics. This model must be tested prospectively before it can be used to inform treatment selection. However, findings demonstrate the potential to improve individual outcomes through algorithm-guided treatment recommendations.
To understand increasing rates of hepatitis C virus (HCV) infection in Tennessee, we conducted testing, risk factor analysis and a nested case–control study among persons who use drugs. During June–October 2016, HCV testing with risk factor assessment was conducted in sexually transmitted disease clinics, family planning clinics and an addiction treatment facility in eastern Tennessee; data were analysed by using multivariable logistic regression. A nested case–control study was conducted to assess drug-using risks and behaviours among persons who reported intranasal or injection drug use (IDU). Of 4753 persons tested, 397 (8.4%) were HCV-antibody positive. HCV infection was significantly associated with a history of both intranasal and IDU (adjusted odds ratio (aOR) 35.4, 95% confidence interval (CI) 24.1–51.9), IDU alone (aOR 52.7, CI 25.3–109.9), intranasal drug use alone (aOR 2.6, CI 1.8–3.9) and incarceration (aOR 2.7, CI 2.0–3.8). By 4 October 2016, 574 persons with a reported history of drug use; 63 (11%) were interviewed further. Of 31 persons who used both intranasal and injection drugs, 26 (84%) reported previous intranasal drug use, occurring 1–18 years (median 5.5 years) before their first IDU. Our findings provide evidence that reported IDU, intranasal drug use and incarceration are independent indicators of risk for past or present HCV infection in the study population.
During puberty young people undergo significant hormonal changes which affect metabolism and, subsequently, health. Evidence suggests there is a period of transient pubertal insulin resistance, with this effect greater in girls than boys. However, the response to everyday high and low glycaemic index (GI) meals remains unknown. Following ethical approval, forty adolescents consumed a high GI or low GI breakfast, in a randomised cross-over design. Capillary blood samples were taken during a 2-h postprandial period, examining the glycaemic and insulinaemic responses. Maturity offset and homoeostatic model assessment (HOMA) were also calculated. The glycaemic response to the breakfasts was similar between boys and girls, as shown by similar peak blood glucose concentrations and incremental AUC (IAUC) following both high and low GI breakfasts (all P>0·05). Girls exhibited a higher peak plasma insulin concentration 30 min post-breakfast following both high GI (P=0·043, g=0·69) and low GI (P=0·010, g=0·84) breakfasts, as well as a greater IAUC following high GI (P=0·041, g=0·66) and low GI (P=0·041, g=0·66) breakfasts. HOMA was positively correlated with the insulinaemic responses (all P<0·0005) and maturity offset (P=0·037). The findings of the present study suggest that pubertal insulin resistance affects the postprandial insulinaemic responses to both high and low GI meals. Specifically, girls exhibit a greater insulinaemic response than boys to both meals, despite similar glycaemic responses. This study is the first to report the glycaemic and insulinaemic responses to everyday meals in boys and girls, supporting the recommendation for young people to base their diet on low GI carbohydrates.
Forest ecosystems in South Africa are at risk from a variety of anthropogenic threats impacting the faunal species dependent on them. These impacts often differ depending on species-specific characteristics. Range data on forest dependent bird species from the South African Bird Atlas Project (SABAP1 and SABAP2) were analysed to determine links between deforestation, species characteristics and range declines. Half of the species studied were found to have declining ranges. Range change data for these species were correlated with data on changes in land cover from 1990 to 2014. To determine which land cover changes affect extinction, occupancy was modelled for 30 sites across South Africa which experienced a loss of more than 10 species. Most species lost were birds of prey or insectivores. Indigenous forest decreased in 17% (n = 5) sites, while plantations/woodlots decreased in 60% (n = 18) sites. Occupancy modelling showed extinction to be mitigated by plantations in 6/28 species, and forest expansion mitigated extinction in 7/28 species. Responses to deforestation did not appear to be related to particular species characteristics. Half of South Africa’s forest-dependent bird species have declining ranges, with the loss of these species most prominent in the Eastern Cape province. Four responses to changes in forest and plantation cover are discussed: direct effects, with forest loss causing species loss; matrix effects, where plantation loss resulted in species loss; degradation of indigenous forest; and the advent of new forest arising from woody thickening caused by carbon fertilisation, which may not result in optimal habitat for forest-dependent birds.
The South African coast contains abundant estuaries and lagoons, most of which originated as river valleys incised during Quaternary sea-level fall and subsequently drowned and/or infilled during rising interglacial sea levels. This chapter discusses these changes and highlights the geomorphological and sedimentological evolution of several southern African estuaries during the Pleistocene to present. The development, infilling and positioning of incised valley systems is mainly controlled by sea-level variation as well as fluvial and marine sediment supply. Most contemporary estuaries in southern Africa show dramatic responses to shorter term sea-level fluctuations and sediment supply during the Holocene. Barring anthropogenic interference, the dynamic behaviour of estuaries, dictated by their transient position and geomorphic character within an incised valley, is considered to fluctuate on centennial to millennial timescales.
Congenital abnormalities of the coronary arteries in the absence of structural heart disease account for a small but interesting percentage of cardiac lesions in children. Their presentation may vary from incidental identification to aborted/sudden cardiac death. Patients with aborted sudden death episodes will require significant support if they develop extensive ischaemic myocardial injury. Ultimately, surgical repair should be carried out as soon as haemodynamic stability is attained and the neurological status is evaluated. The aims of this article were to provide a review of congenital abnormalities of the coronary arteries most commonly seen in children in the ICU as well as to review the current critical-care management thereof.
Various environmental factors have been associated with the timing of eruption of primary dentition, but the evidence to date comes from small studies with limited information on potential risk factors. We aimed to investigate associations between tooth emergence patterns and pre-conception, pregnancy and postnatal influences. Dentition patterns were recorded at ages 1 and 2 years in 2915 children born to women in the Southampton Women’s Survey from whom information had been collected on maternal factors before conception and during pregnancy. In mutually adjusted regression models we found that: children were more dentally advanced at ages 1 and 2 years if their mothers had smoked during pregnancy or they were longer at birth; mothers of children whose dental development was advanced at age 2 years tended to have poorer socioeconomic circumstances, and to have reported a slower walking speed pre-pregnancy; and children of mothers of Asian ethnicity had later tooth development than those of white mothers. The findings add to the evidence of environmental impacts on the timing of the eruption of primary dentition in indicating that maternal smoking during pregnancy, socio-economic status and physical activity (assessed by reported walking speed) may influence the child’s primary dentition. Early life factors, including size at birth are also associated with dentition patterns, as is maternal ethnicity.
Background: Clinical perfectionism is a risk and maintaining factor for anxiety disorders, depression and eating disorders. Aims: The aim was to examine the psychometric properties of the 12-item Clinical Perfectionism Questionnaire (CPQ). Method: The research involved two samples. Study 1 comprised a nonclinical sample (n = 206) recruited via the internet. Study 2 comprised individuals in treatment for an eating disorder (n = 129) and a community sample (n = 80). Results: Study 1 factor analysis results indicated a two-factor structure. The CPQ had strong correlations with measures of perfectionism and psychopathology, acceptable internal consistency, and discriminative and incremental validity. The results of Study 2 suggested the same two-factor structure, acceptable internal consistency, and construct validity, with the CPQ discriminating between the eating disorder and control groups. Readability was assessed as a US grade 4 reading level (student age range 9–10 years). Conclusions: The findings provide evidence for the reliability and validity of the CPQ in a clinical eating disorder and two separate community samples. Although further research is required the CPQ has promising evidence as a reliable and valid measure of clinical perfectionism.
Aquifers of the Austral region are globally significant in terms of their biodiversity. They support a rich and unique fauna, specifically adapted to the harsh subterranean environment. In this chapter we review the nature and diversity of groundwater ecosystems across the Austral region. We consider first the global origins of the Australian groundwater fauna, and their distributions across Gondwana. As the Australian continent evolved, the western shield emerged from the sea during the Proterozoic, which has led to a distinct fauna in those ancient landscapes. In the ‘newer’ eastern Austral regions there has also emerged a rich groundwater fauna, and here we review the current knowledge of fauna in eastern Australia and New Zealand. Mining and agricultural development threaten groundwater ecosystems across the region, but perhaps the greatest threat is our current lack of knowledge of these unique and important ecosystems and their biota. New approaches for conservation planning provide hope for improved recognition and protection of groundwater ecosystems, but with relatively little surveying of groundwater fauna having been done across the region, much remains undiscovered.
Being the driest inhabited continent on Earth, the availability of water has always been a critical factor shaping the evolution and distribution of species across Australia. So too, the availability of water is critical to the survival and prosperity of human populations across the broader region, from small outback towns to major capital cities. As human pressures increase demand for water, groundwater is increasingly being used to meet water needs of households, industries and farms. Groundwater use accounts for around 20% of the total water used across Australia, it is more than 50% in New Zealand (Fenwick et al. 2004), and in many areas it is the only reliable water supply.
Despite many advances in recent years for patients with critical paediatric and congenital cardiac disease, significant variation in outcomes remains across hospitals. Collaborative quality improvement has enhanced the quality and value of health care across specialties, partly by determining the reasons for variation and targeting strategies to reduce it. Developing an infrastructure for collaborative quality improvement in paediatric cardiac critical care holds promise for developing benchmarks of quality, to reduce preventable mortality and morbidity, optimise the long-term health of patients with critical congenital cardiovascular disease, and reduce unnecessary resource utilisation in the cardiac intensive care unit environment. The Pediatric Cardiac Critical Care Consortium (PC4) has been modelled after successful collaborative quality improvement initiatives, and is positioned to provide the data platform necessary to realise these objectives. We describe the development of PC4 including the philosophical, organisational, and infrastructural components that will facilitate collaborative quality improvement in paediatric cardiac critical care.
Low weight at birth has previously been shown to be associated with a number of adult diseases such as type 2 diabetes, cardiovascular disease, high blood pressure, and obesity later in life. Genome-wide association studies (GWAS) have been published for singleton-born individuals, but the role of genetic variation in birth weight (BW) in twins has not yet been fully investigated. A GWAS was performed in 4,593 female study participants with BW data available from the TwinsUK cohort. A genome-wide significant signal was found in chromosome 9, close to the NTRK2 gene (OMIM: 600456). QIMR, an Australian twin cohort (n = 3,003), and UK-based singleton-birth individuals from the Hertfordshire cohort (n = 2,997) were used as replication for the top two single nucleotide polymorphism (SNPs) underpinning this signal, rs12340987 and rs7849941. The top SNP, rs12340987, was found to be in the same direction in the Australian twins and in the singleton-born females (fixed effects meta-analysis beta = -0.13, SE = 0.02, and p = 1.48 × 10−8) but not in the singleton-born males tested. These findings provide an important insight into the genetic component of BW in twins who are normally excluded due to their lower BW when compared with singleton births, as well as the difference in BW between twins. The NTRK2 gene identified in this study has previously been associated with obesity.
Several factors threaten populations of albatrosses and giant petrels, including the impact of fisheries bycatch and, at some colonies, predation from introduced mammals. We undertook population monitoring on Gough Island of three albatross species (Tristan albatross Diomedea dabbenena L., sooty albatross Phoebetria fusca Hilsenberg, Atlantic yellow-nosed albatross Thalassarche chlororhynchos Gmelin) and southern giant petrels Macronectes giganteus (Gmelin). Over the study period, numbers of the Critically Endangered Tristan albatross decreased at 3.0% a year. Breeding success for this species was low (23%), and in eight count areas was correlated (r2 = 0.808) with rates of population decline, demonstrating chick predation by house mice Mus musculus L. is driving site-specific trends and an overall decline. Numbers of southern giant petrels were stable, contrasting with large increases in this small population since 1979. Significant population declines were not detected for either the Atlantic yellow-nosed or sooty albatross, however, caution should be applied to these results due to the small proportion of the population monitored (sooty albatross) and significant interannual variation in numbers. These trends confirm the Critically Endangered status of the Tristan albatross but further information, including a more accurate estimate of sooty albatross population size, is required before determining island wide and global population trends of the remaining species.
A series of very wide (up to 15 km) raised shore platforms in the Scottish Hebrides are identified and described for the first time and are considered part of a high rock platform shoreline in the western isles of Scotland described by W. B. Wright in his classic Geological Magazine paper a century ago as a ‘preglacial’ feature. Subsequent interpretations suggesting that the platforms were produced during the Pleistocene are rejected here in favour of a speculative hypothesis that the features are part of the well-known strandflat that is extensively developed across large areas of the northern hemisphere. It is argued that the Scottish strandflat developed during the Pliocene and was later subjected to extensive Pleistocene glacial erosion such that only a few areas of platform have survived in the Scottish Inner Hebrides (ice-proximal) while they are well-preserved in the Outer Hebrides (ice-distal). Support for a Pliocene hypothesis is provided by the marine oxygen isotope record for this time interval which points to prolonged periods of relative sea level stability as would be required for the production of such wide features. This hypothesis for the formation of a Scottish strandflat not only provides an elegant explanation for the origin and age of the raised rock platform fragments that occur throughout the western isles of Scotland, but it may also have relevance for other coastal areas of the northern hemisphere (e.g. Norway, Greenland, Alaska) where the strandflat is a well-developed feature.