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Memory symptoms and objective impairment are common in HIV disease and are associated with disability. A paradoxical issue is that objective episodic memory failures can interfere with accurate recall of memory symptoms. The present study assessed whether responses on a self-report scale of memory symptoms demonstrate measurement invariance in persons with and without objective HIV-associated memory impairment.
In total, 505 persons with HIV completed the Prospective and Retrospective Memory Questionnaire (PRMQ). Objective memory impairment (n = 141) was determined using a 1-SD cutoff on clinical tests of episodic memory. PRMQ measurement invariance was assessed by confirmatory factor analyses examining a one-factor model with increasing cross-group equality constraints imposed on factor loadings and item thresholds (i.e., configural, weak, and strong invariance).
Configural model fit indicated that identical items measured a one-factor model for both groups. Comparison to the weak model indicated that factor loadings were equivalent across groups. However, there was evidence of partial strong invariance, with two PRMQ item thresholds differing across memory impairment groups. Post hoc analyses using a 1.5-SD memory impairment cutoff (n = 77) revealed both partial weak and partial strong invariance, such that PRMQ item loadings differed across memory groups for three items.
The PRMQ demonstrated a robust factor structure among persons with and without objective HIV-associated memory impairment. However, on select PRMQ items, individuals with memory impairment reported observed scores that were relatively higher than their latent score, while items were more strongly associated with the memory factor in a group with greater memory impairment.
Self-harm and suicidal behaviour are recognised as public health concerns. Prolonged social withdrawal behaviour, or hikikomori, is reported as a risk factor for suicidal behaviour.
To examine the occurrence and additional risk of prolonged social withdrawal behaviour on self-harm and suicidal behaviour among Chinese university students.
A cross-sectional online survey was conducted with three universities in southern China. A two-stage random sampling was adopted for recruitment, with students in different years of study, in different departments of each participating university. Hierarchical logistic regression analyses were conducted to investigate the sociodemographic and psychological correlates of self-harm and suicidal behaviours among male and female participants with hikikomori status.
Of the students who completed the online survey, 1735 (72.23%) were included in the analysis; 11.5% (n = 200) reported self-harm behaviour and 11.8% (n = 204) reported suicidal behaviours in the past 12 months. Men showed a higher prevalence rate of self-harm than women (14.7% v. 10.8%, P = 0.048), but a similar rate of suicidal behaviours (11.9% v. 11.3%, P = 0.78). The overall prevalence rate of social withdrawal behaviour was 3.2% (7.0% for men and 2.3% for women, P < 0.001). Prolonged social withdrawal behaviour status was significantly associated with self-harm (odds ratio 2.00, 95% CI 1.22–3.29) and suicidal behaviour (odds ratio 2.35, 95% CI 1.45–3.81). However, the associations became statistically insignificant after adjustment for psychological factors in the final models in the logistic regression analyses.
Prolonged social withdrawal behaviour appears to be associated with self-harm and suicidal behaviour, but psychological factors have stronger links with suicidality.
Throughout the Ediacaran Period, variable water-column redox conditions persisted along productive ocean margins due to a complex interplay between nutrient supply and oceanographic restriction. These changing conditions are considered to have influenced early faunal evolution, with marine anoxia potentially inhibiting the development of the ecological niches necessary for aerobic life forms. To understand this link between oxygenation and evolution, the combined geochemical and palaeontological study of marine sediments is preferable. Located in the Yangtze Gorges region of southern China, lagoonal black shales at Miaohe preserve alga and putative metazoans, including Eoandromeda, a candidate total-group ctenophore, thereby providing one example of where integrated study is possible. We present a multi-proxy investigation into water-column redox variability during deposition of these shales (c. 560–551 Ma). For this interval, reactive iron partitioning indicates persistent water-column anoxia, while trace metal enrichments and other geochemical data suggest temporal fluctuations between ferruginous, euxinic and rare suboxic conditions. Although trace metal and total organic carbon values imply extensive basin restriction, sustained trace metal enrichment and δ15Nsed data indicate periodic access to open-ocean inventories across a shallow-marine sill. Lastly, δ13Corg values of between −35‰ and −40‰ allow at least partial correlation of the shales at Miaohe with Member IV of the Doushantuo Formation. This study provides evidence for fluctuating redox conditions in the lagoonal area of the Yangtze platform during late Ediacaran time. If these low-oxygen environments were regionally characteristic, then the restriction of aerobic fauna to isolated environments can be inferred.
Adolescent risk for self-injurious thoughts and behaviors (STBs) involves disturbance across multiple systems (e.g., affective valence, arousal regulatory, cognitive and social processes). However, research integrating information across these systems is lacking. Utilizing a multiple-levels-of-analysis approach, this person-centered study identified psychobiological stress response profiles and linked them to cognitive processes, interpersonal behaviors, and STBs. At baseline, adolescent girls (N = 241, Mage = 14.68 years, Range = 12–17) at risk for STBs completed the Trier Social Stress Test (TSST), questionnaires, and STB interviews. Positive affect (PA), negative affect (NA), and salivary cortisol (SC) were assessed before and after the TSST. STBs were assessed again during 3, 6, and 9 month follow-up interviews. Multitrajectory modeling of girls’ PA, NA, and SC revealed four profiles, which were compared on cognitive and behavioral correlates as well as STB outcomes. Relative to normative, girls in the affective distress, hyperresponsive, and hyporesponsive subgroups were more likely to report negative cognitive style (all three groups) and excessive reassurance seeking (hyporesponsive only) at baseline, as well as nonsuicidal self-injury (all three groups) and suicidal ideation and attempt (hyporesponsive only) at follow-up. Girls’ close friendship characteristics moderated several profile–STB links. A synthesis of the findings is presented alongside implications for person-centered tailoring of intervention efforts.
Agenesis of the corpus callosum (AgCC) is associated with a range of cognitive deficits, including mild to moderate problems in higher order executive functions evident in neuropsychological assessments. Previous research has also suggested a lack of self-awareness in persons with AgCC.
We investigated daily executive functioning and self-awareness in 36 individuals with AgCC by analyzing self-ratings on the Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A), as well as ratings on the same instrument from close relatives. Discrepancies between self- and informant-ratings were compared to the normative sample and exploratory analyses examined possible moderating effects of participant and informant characteristics.
Significant deficiencies were found in the Behavioral Regulation and Metacognitive indices for both the self and informant results, with elevated frequency of metacognition scores in the borderline to clinical range. Informants also endorsed elevated frequency of borderline to clinically significant behavioral regulation scores. The proportion of AgCC participants whose self-ratings indicated less metacognitive impairment than informant-ratings was greater than in the normative sample. Self-ratings of behavioral regulation impairment decreased with age and informant-ratings of metacognition were higher in males than females.
These findings provide evidence that individuals with AgCC experience mild to moderate executive functioning problems in everyday behavior which are observed by others. Results also suggest a lack of self-understanding or insight into the severity of these problems in the individuals with AgCC, particularly with respect to their metacognitive functioning.
Mental health policy makers require evidence-based information to optimise effective care provision based on local need, but tools are unavailable.
To develop and validate a population-level prediction model for need for early intervention in psychosis (EIP) care for first-episode psychosis (FEP) in England up to 2025, based on epidemiological evidence and demographic projections.
We used Bayesian Poisson regression to model small-area-level variation in FEP incidence for people aged 16–64 years. We compared six candidate models, validated against observed National Health Service FEP data in 2017. Our best-fitting model predicted annual incidence case-loads for EIP services in England up to 2025, for probable FEP, treatment in EIP services, initial assessment by EIP services and referral to EIP services for ‘suspected psychosis’. Forecasts were stratified by gender, age and ethnicity, at national and Clinical Commissioning Group levels.
A model with age, gender, ethnicity, small-area-level deprivation, social fragmentation and regional cannabis use provided best fit to observed new FEP cases at national and Clinical Commissioning Group levels in 2017 (predicted 8112, 95% CI 7623–8597; observed 8038, difference of 74 [0.92%]). By 2025, the model forecasted 11 067 new treated cases per annum (95% CI 10 383–11 740). For every 10 new treated cases, 21 and 23 people would be assessed by and referred to EIP services for suspected psychosis, respectively.
Our evidence-based methodology provides an accurate, validated tool to inform clinical provision of EIP services about future population need for care, based on local variation of major social determinants of psychosis.
Newborns with neonatal abstinence syndrome (NAS) display symptoms related to neurologic excitability and autonomic dysfunction that result in increased metabolic demands. These infants also exhibit feeding difficulties and/or hyperphagia. Because the effects of these symptoms and behaviors on growth are unknown, we sought to measure serial body composition measurements over the first 4 months in infants with NAS requiring pharmacologic treatment using air displacement plethysmography. Fourteen infants of singleton birth with appropriate-for-gestational-age (AGA) weight and a gestational age of ≥35 weeks and <42 weeks were evaluated. In mixed-effects models, per week, infants increased in mean fat percent by 1.1% (95% confidence interval [CI]: 0.85–1.43), fat mass by 90 g (CI: 70–100), and fat-free mass by 140 g (CI: 130–150). The subgroup of infants (N = 5) requiring multidrug therapy for symptom control had lower mean fat percent (−1.2%, CI: −5.2–2.1), fat mass (−60 g, CI: −25–13), and fat-free mass (−270 g, CI: −610–80) across time compared to infants requiring monotherapy. We are the first to report how body composition measures change over time in a small group of patients with NAS. Infants with NAS were smaller and leaner in the first several weeks compared to previously reported body composition measurements in term infants, but grew similarly to their healthy counterparts by 16 weeks. Infants with more severe NAS may be at risk for abnormalities in longer term growth.
A programmable borehole measurement system was deployed in hot water drilled ice holes during the ‘Bed Access and Monitoring of Ice Sheet History’ (BEAMISH) project to drill to the bed of the Rutford Ice Stream in West Antarctica. This system operates autonomously (no live data) after deployment, and records borehole diameter (non-contact measurement), water column pressure, heading and inclination. Three cameras, two sideways looking and one vertical, are also included for visual inspection of hole integrity and sediments. The system is small, lightweight (~35.5 kg) and low power using only 6 ‘D’ cell sized lithium batteries, making it ideal for transport and use in remote field sites. The system is 2.81 m long and 165 mm in diameter, and can be deployed attached to the drill hose for measurements during drilling or on its own deployment line afterwards. The full system is discussed in detail, highlighting design strengths and weaknesses. Data from the BEAMISH project are also presented in the form of camera images showing hole integrity, and sensor data used to calculate borehole diameter through the full length of the hole. These data are used to show confidence in hole verticality and subsurface cavity development and connection.
During the 2018/19 Antarctic field season, the British Antarctic Survey (BAS) Basal conditions on Rutford Ice Stream: BEd Access, Monitoring and Ice Sheet History’ (BEAMISH) project drilled three holes through the Rutford Ice Stream, West Antarctica. At up to 2154 m, these are the deepest hot water drilled subglacial access holes yet created, enabling the recovery of sediment from the subglacial environment, and instrumenting the ice stream and its bed. The BEAMISH hot-water drill system was built on extensive experience with the BAS ice shelf hot-water drill and utilises many identical components. With up to 1 MW of heating power available, the hot water drill produces 140 L min−1 of water at 85°C to create a 300 mm diameter access hole to the base of the ice stream. New systems and processes were developed for BEAMISH to aid critical aspects of deep access drilling, most notably the creation of cavities interlinking boreholes at 230 m below the surface and enabling water recirculation throughout the deep drilling operations. The modular design of the BEAMISH drill offers many benefits in its adaptability, redundancy, and minimal logistical footprint. These design features can easily accommodate the modifications needed for future deep, clean access hole creation in the exploration of subglacial environments.
The Antebellum American South experienced rapid biological innovation centered around an active market for new cotton seed varieties, despite the absence of intellectual property rights. Contemporaries complained new seed was initially offered at high prices, which subsequently collapsed. Using local newspaper evidence, this paper documents this market’s operation. It then rationalizes the price movements given the potential of improved seed to multiply at finite rates. The initial prices were sufficiently high to provide meaningful incentives to innovate. This study also identifies information problems affecting the cotton seed market, leading observers to claim too many new varieties were released, not too few.
Late-life depression has substantial impacts on individuals, families and society. Knowledge gaps remain in estimating the economic impacts associated with late-life depression by symptom severity, which has implications for resource prioritisation and research design (such as in modelling). This study examined the incremental health and social care expenditure of depressive symptoms by severity.
We analysed data collected from 2707 older adults aged 60 years and over in Hong Kong. The Patient Health Questionnaire-9 (PHQ-9) and the Client Service Receipt Inventory were used, respectively, to measure depressive symptoms and service utilisation as a basis for calculating care expenditure. Two-part models were used to estimate the incremental expenditure associated with symptom severity over 1 year.
The average PHQ-9 score was 6.3 (standard deviation, s.d. = 4.0). The percentages of respondents with mild, moderate and moderately severe symptoms and non-depressed were 51.8%, 13.5%, 3.7% and 31.0%, respectively. Overall, the moderately severe group generated the largest average incremental expenditure (US$5886; 95% CI 1126–10 647 or a 272% increase), followed by the mild group (US$3849; 95% CI 2520–5177 or a 176% increase) and the moderate group (US$1843; 95% CI 854–2831, or 85% increase). Non-psychiatric healthcare was the main cost component in a mild symptom group, after controlling for other chronic conditions and covariates. The average incremental association between PHQ-9 score and overall care expenditure peaked at PHQ-9 score of 4 (US$691; 95% CI 444–939), then gradually fell to negative between scores of 12 (US$ - 35; 95% CI - 530 to 460) and 19 (US$ -171; 95% CI - 417 to 76) and soared to positive and rebounded at the score of 23 (US$601; 95% CI -1652 to 2854).
The association between depressive symptoms and care expenditure is stronger among older adults with mild and moderately severe symptoms. Older adults with the same symptom severity have different care utilisation and expenditure patterns. Non-psychiatric healthcare is the major cost element. These findings inform ways to optimise policy efforts to improve the financial sustainability of health and long-term care systems, including the involvement of primary care physicians and other geriatric healthcare providers in preventing and treating depression among older adults and related budgeting and accounting issues across services.
The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
Mortality risk is known to be associated with many physiological or biochemical risk factors, and polygenic risk scores (PRSs) may offer an additional or alternative approach to risk stratification. We have compared the predictive value of common biochemical tests, PRSs and information on parental survival in a cohort of twins and their families. Common biochemical test results were available for up to 13,365 apparently healthy men and women, aged 17−93 years (mean 49.0, standard deviation [SD] 13.7) at blood collection. PRSs for longevity were available for 14,169 study participants and reported parental survival for 25,784 participants. A search for information on date and cause of death was conducted through the Australian National Death Index, with median follow-up of 11.3 years. Cox regression was used to evaluate associations with mortality from all causes, cancers, cardiovascular diseases and other causes. Linear relationships with all-cause mortality were strongest for C-reactive protein, gamma-glutamyl transferase, glucose and alkaline phosphatase, with hazard ratios (HRs) of 1.16 (95% CI [1.07, 1.24]), 1.15 (95% CI 1.04–1.21), 1.13 (95% CI [1.08, 1.19]) and 1.11 (95% CI [1.05, 1.88]) per SD difference, respectively. Significant nonlinear effects were found for urea, uric acid and butyrylcholinesterase. Lipid risk factors were not statistically significant for mortality in our cohort. Family history and PRS showed weaker but significant associations with survival, with HR in the range 1.05 to 1.09 per SD difference. In conclusion, biochemical tests currently predict long-term mortality more strongly than genetic scores based on genotyping or on reported parental survival.
A pandemic arises when biology meets politics. The biology may be universal, but politics are local. Some nations suffer many thousands of deaths; some hundreds. Same virus; different politics. Economic development accounts for some of the differences, but even nations at the same level of development can have radically different pandemics. If politics is destiny, then our fate is in our hands.
The threat of the coronavirus to a community raises a political question: What is the nation prepared to do? In the United States and the United Kingdom, the initial answer was “very little.” Other places – for example, China, Israel, or South Korea – were prepared to do quite a lot. The statistics show the consequences.