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Substantial clinical heterogeneity of major depressive disorder (MDD) suggests it may group together individuals with diverse aetiologies. Identifying distinct subtypes should lead to more effective diagnosis and treatment, while providing more useful targets for further research. Genetic and clinical overlap between MDD and schizophrenia (SCZ) suggests an MDD subtype may share underlying mechanisms with SCZ.
The present study investigated whether a neurobiologically distinct subtype of MDD could be identified by SCZ polygenic risk score (PRS). We explored interactive effects between SCZ PRS and MDD case/control status on a range of cortical, subcortical and white matter metrics among 2370 male and 2574 female UK Biobank participants.
There was a significant SCZ PRS by MDD interaction for rostral anterior cingulate cortex (RACC) thickness (β = 0.191, q = 0.043). This was driven by a positive association between SCZ PRS and RACC thickness among MDD cases (β = 0.098, p = 0.026), compared to a negative association among controls (β = −0.087, p = 0.002). MDD cases with low SCZ PRS showed thinner RACC, although the opposite difference for high-SCZ-PRS cases was not significant. There were nominal interactions for other brain metrics, but none remained significant after correcting for multiple comparisons.
Our significant results indicate that MDD case-control differences in RACC thickness vary as a function of SCZ PRS. Although this was not the case for most other brain measures assessed, our specific findings still provide some further evidence that MDD in the presence of high genetic risk for SCZ is subtly neurobiologically distinct from MDD in general.
We sought to explore factors associated with depressive symptom severity among older persons (≥60 years of age) and to compare the depressive symptoms commonly experienced by older elderly (≥75 years) with those commonly experienced by younger elderly (<75 years).
Secondary analysis was conducted on data from a nationally representative survey.
Four parishes in Jamaica.
A total of 2,943 older community dwellers participated.
The survey included the Zung Self-rating Depression Scale (ZSDS), the Mini Mental State Examination (MMSE), and items on age, sex, and educational level. Linear regression analysis was used to determine the association between ZSDS score and: age, sex, MMSE score, and educational level. Logistic regression analysis was used to determine, for each ZSDS item, whether particular responses were more associated with older or younger elderly.
Higher ZSDS scores were associated with increasing age (B = 0.13, p < 0.001), lower MMSE score (B = −0.42, p < 0.001), the female sex (B = 3.52, p < 0.001), and lower educational level (B = −1.27, p < 0.001). The ZSDS items that were endorsed significantly more (p < 0.05) by older elderly related to negative evaluations about their functionality and value. Hopelessness was also more prominent among the older elderly. The items that were endorsed significantly more (p < 0.05) by the younger elderly had less of a focus.
Among older persons, increasing age was associated with marginally higher levels of depressive symptoms. Female gender, cognitive deficits, preoccupations about value and functionality, and feelings of hopelessness may serve as useful screening parameters.
In this study, we describe a contained measles outbreak in a London prison, the second such outbreak in a custodial setting. Once vaccination commenced, just under a third of eligible prisoners were immunised due to a low uptake of the vaccine. We conducted a root-cause analysis in order to identify factors which may have prevented or altered the course of the outbreak. Our analysis revealed that many of the factors identified are those that cannot be easily changed. It is unlikely that mass vaccination at the time, even in the absence of some of the more easily rectifiable issues, could have fully avoided further cases in the event of a mass outbreak. Both measles outbreaks in a custodial setting started with a member of staff and immunisation status of the staff were largely unknown. We argue that mass vaccination following an outbreak in a prison is unlikely to fully prevent a mass outbreak, and that implementing opt-out testing, empirical vaccination and insisting on full immunisation of staff are most likely to both prevent and contain outbreaks in the future.
Conservation resources are limited, yet an increasing number of species are under threat. Assessing species for their conservation needs is, therefore, a vital first step in identifying and prioritizing species for both ex situ and in situ conservation actions. Using a transparent, logical and objective method, the Conservation Needs Assessment process developed by Amphibian Ark uses current knowledge of species in the wild to determine those with the most pressing conservation needs, and provides a foundation for the development of holistic conservation action plans that combine in situ and ex situ actions as appropriate. These assessments allow us to maximize the impact of limited conservation resources by identifying which measures could best serve those species requiring help. The Conservation Needs Assessment complements the IUCN Red List assessment, and together they provide a more holistic guide to conservation priorities and actions. Conservation Needs Assessments generate national prioritized lists of species recommended for conservation action. These can subsequently be used to assist in the development of species recovery plans and national action plans, or to inform national conservation priorities better. Additional tools that will evaluate the recommendations for ex situ rescues, to determine the best candidates for conservation breeding programmes, are currently under development.
Electron and proton microprobes, along with electron backscatter diffraction (EBSD) analysis were used to study the microstructure of the contemporary Al–Cu–Li alloy AA2099-T8. In electron probe microanalysis, wavelength and energy dispersive X-ray spectrometry were used in parallel with soft X-ray emission spectroscopy (SXES) to characterize the microstructure of AA2099-T8. The electron microprobe was able to identify five unique compositions for constituent intermetallic (IM) particles containing combinations of Al, Cu, Fe, Mn, and Zn. A sixth IM type was found to be rich in Ti and B (suggesting TiB2), and a seventh IM type contained Si. EBSD patterns for the five constituent IM particles containing Al, Cu, Fe, Mn, and Zn indicated that they were isomorphous with four phases in the 2xxx series aluminium alloys including Al6(Fe, Mn), Al13(Fe, Mn)4 (two slightly different compositions), Al37Cu2Fe12 and Al7Cu2Fe. SXES revealed that Li was present in some constituent IM particles. Al SXES mapping revealed an Al-enriched (i.e., Cu, Li-depleted) zone in the grain boundary network. From the EBSD analysis, the kernel average misorientation map showed higher levels of localized misorientation in this region, suggesting greater deformation or stored energy. Proton-induced X-ray emission revealed banding of the TiB2 IM particles and Cu inter-band enrichment.
The pepper weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae), is the most important pest of pepper (Capsicum Linnaeus; Solanaceae) crops in North America. Native to Mexico, the southern United States of America, and Central America, it is intercepted in Canada when peppers are imported to supplement domestic production. Given the proximity of greenhouse and field production to packing facilities, this pest poses a serious risk to the cultivation of peppers in Canada. Once established, it is difficult to control because immature stages of the weevil are protected within the pepper fruit. As such, chemical control targeting these life stages is not effective, and other strategies, including biological control, may prove useful. To explore the potential for biological control options to manage the pepper weevil in areas at risk in Canada, natural enemy surveys were conducted in southern Ontario following the reports of transient, localised field populations in 2016. Parasitoids belonging to three Hymenoptera families including Pteromalidae (Jaliscoa hunteri Crawford, Pteromalus anthonomi Ashmead), Eupelmidae (Eupelmus pulchriceps Cameron), and Braconidae (Nealiolus Mason species, Bracon Fabricius species) were reared from infested field-collected pepper fruits. Together, these new natural enemy records could facilitate the exploration and development of novel agents for the biological control of the pepper weevil.
We present an in-depth study of metal-poor stars, based high resolution spectra combined with newly released astrometric data from Gaia, with special attention to observational uncertainties. The results are compared to those of other studies, including Gaia benchmark stars. Chemical evolution models are discussed, highlighting few puzzles that are still affecting our understanding of stellar nucleosynthesis and of the evolution of our Galaxy.
Cubic boron nitride (cBN) is a synthetic wide band gap material that has attracted attention due to its high thermal conductivity, optical transparency and optical emission. In this work, defects in cBN have been investigated using experimental and theoretical X-ray absorption near edge structure (XANES). Vacancy and O substitutional defects were considered, with O substituted at the N site (ON) to be the most energetically favorable. All defects produce unique signatures in either the B or N K-edges and can thus be identified using XANES. The calculations coupled with electron-irradiation / annealing experiments strongly suggest that ON is the dominant defect in irradiated cBN and remains after annealing. This defect is a likely source of optical emission in cBN.
We aimed to determine the prevalence of alcohol use among older Jamaicans as well as to explore among this population the relationships between alcohol use and: age, sex, depressive symptoms, and life satisfaction. Although the nature of these relationships among the proposed study population were uncertain, in other settings alcohol use has tended to decline with increasing age, occur more commonly among men than women, and show non-linear relationships with depressive symptoms and life satisfaction.
Data gathered by two-stage cluster sampling for a nationally representative health and lifestyle survey of 2,943 community-dwelling older Jamaicans, aged 60 to 103 years, were subjected to secondary analysis using the Student's t-test and χ2 test as appropriate.
Current alcohol use was reported by 21.4% of the participants. It steadily declined with age and was six times more prevalent among men (37.6%) than women (6.2%). These findings were statistically significant as were associations of current alcohol use with comparatively lower levels of depressive symptoms. Current alcohol use was also more prevalent among persons who were either highly satisfied or highly dissatisfied with their lives, compared to others who had levels of life satisfaction between these two extremes.
Current alcohol use among older Jamaicans occurs primarily among men, declines with increasing age, and is associated with a relatively low likelihood of depression. It is also associated with very high and very low levels of life satisfaction.
Due to the non-curative nature of high grade brain tumours “difficult discussions” about goals of care, advance care planning, palliative care, and end of life are inherent to the practice of the neuro-oncology team. Clinician and patient barriers are common and may include anxiety about destroying hope, lack of readiness to discuss end of life topics, difficulty managing emotional responses, and concerns over competency in facilitating difficult discussions. Nonetheless, clinician comfort and skill in facilitating these discussions is critical and can impact patient perception of illness, coping response, and ability to make decisions about care. Methods At our regional cancer centre, a novel quality improvement initiative was designed to bring monthly case presentation of “difficult discussions” into a pre-existing weekly multi-disciplinary case conference (MCC). We will describe the rationale and developmental processes behind this initiative. Roughly 15 neuro-oncology clinicians attended each case conference, with guest attendance from palliative care and psychosocial oncology. Clinician groups represented included physicians (77%), nurses (8%), nurse practitioners (10 %), and occupational therapists (5%). Baseline and monthly surveys were administered to determine clinicians’ self- rated practices, skills, and attitudes towards “difficult discussions”. Results Early findings indicate that the initiative has been well-received. Physicians indicated highest levels of agreement with the statement “I feel that having difficult discussions is part of my responsibility”. Non physician groups indicated the greatest agreement that the intervention is beneficial to their practice. Discussion: Our challenges and successes may help guide others to incorporate a similar initiative at disease-site meetings.
Objectives: Individuals with schizophrenia have difficulties on measures of executive functioning such as initiation and suppression of responses and strategy development and implementation. The current study thoroughly examines performance on the Hayling Sentence Completion Test (HSCT) in individuals with schizophrenia, introducing novel analyses based on initiation errors and strategy use, and association with lifetime clinical symptoms. Methods: The HSCT was administered to individuals with schizophrenia (N=77) and age- and sex-matched healthy controls (N=45), along with background cognitive tests. The standard HSCT clinical measures (initiation response time, suppression response time, suppression errors), composite initiation and suppression error scores, and strategy-based responses were calculated. Lifetime clinical symptoms [formal thought disorder (FTD), positive, negative] were calculated using the Lifetime Dimensions of Psychosis Scale. Results: After controlling for baseline cognitive differences, individuals with schizophrenia were significantly impaired on the suppression response time and suppression error scales. For the novel analyses, individuals with schizophrenia produced a greater number of initiation errors and subtly wrong errors, and produced fewer responses indicative of developing an appropriate strategy. Strategy use was negatively correlated with FTD symptoms in individuals with schizophrenia. Conclusions: The current study provides further evidence for deficits in the initiation and suppression of verbal responses in individuals with schizophrenia. Moreover, an inability to attain a strategy at least partly contributes to increased semantically connected errors when attempting to suppress responses. The association between strategy use and FTD points to the involvement of executive deficits in disorganized speech in schizophrenia. (JINS, 2016, 22, 735–743)
Background: In British Columbia, neuromuscular disease accounts for 31% of IVIg use, at a cost of $10.1 M. In addition to the new screening pathway, the BC Neuromuscular IVIg Program developed the Chronic High User Project to identify areas for improvement in utilization. Methods: Utilizing CTR data, all patients on IVIg maintenance therapy for approved neuromuscular conditions between April 1, 2013 and March 31, 2014 were identified. Patients receiving higher than usual IVIG treatments (CIDP and MG >1110 grams/year, MMNCB > 1400 grams/year) were evaluated. Following panel review, utilization data was compared with a second cohort (2014 to 2015) to determine impact. Following review, appropriateness of treatment was determined by consensus from a 3-member panel, and recommendations were made. Results: Of 377 patients, 38 “High Users” were identified. 29 cases were determined to be appropriate; 9 were not. There was a reduction in mean grams/episode in CIDP (1135g to 990g) and MG (1099 g to 1022g) between cohorts. The mean grams/episode for MMNCB did not change. Conclusions: In specific cases, the IVIg High User Program identified patients in whom the treatment could be optimized. However, the vast majority of use of IVIg for Neuromuscular Disease in BC is appropriate, including in patients requiring higher that “usual” doses.
In this work we study the effect of satellite accretion on the building-up of the radial stellar age distribution in the discs of spiral galaxies. In addition, we analyse its effect on other chemical and dynamical properties of these systems up to their outskirts.
Making use of a fiducial set of simulated disc galaxies spanning a wide range of mass, we examine the influence of stellar mass in the radial metallicity gradients and compare to observational trends from Ho et al. (2015).
We summarize the results obtained from our suite of chemical evolution models for spiral disks, computed for different total masses and star formation efficiencies. Once the gas, stars and star formation radial distributions are reproduced, we analyze the Oxygen abundances radial profiles for gas and stars, in addition to stellar averaged ages and global metallicity. We examine scenarios for the potential origin of the apparent flattening of abundance gradients in the outskirts of disk galaxies, in particular the role of molecular gas formation prescriptions.