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Objectives: Emerging work reveals the neuroanatomic changes that compromise metacognition; however, little is known about the impact of premorbid factors. Research suggests that psychological variables influence the perception of cognition, but whether they influence the accuracy of those perceptions (i.e., metacognition) has not been directly examined. Participants and Methods: Using Latent Class Analysis (LCA), we tested for discrete personality (NEOFFI) and mood (STAI, BDI-II, and GDS) classes among a community-based cohort of 151 older adults, enrolled in the NKI-Rockland study. Metamemory was calculated by comparing subjective memory ratings (modified Cognitive Failures Questionnaire) to objective memory (Rey Auditory Verbal Learning Test) to determine the degree to which individuals were overconfident, underconfident, or accurate in their self-assessment. A generalized linear model was used to examine whether metamemory differed across the emergent classes. A one sample t test was used to determine whether the metamemory scores of the emergent classes were statistically significantly different from zero, that is, over or under confident. Results: Two discrete classes emerged in the LCA: Class 1 was characterized predominantly by high extraversion and conscientiousness and low neuroticism and anxiety; Class 2 was characterized predominantly by low extraversion and conscientiousness and high neuroticism and anxiety. Metamemory differed significantly as a function of Class Membership (F(4,151)=5.42; p<.001), with Class 1 demonstrating accurate metamemory (M=0.21; SD=1.31) and Class 2 demonstrating under-confidence (M=−0.59; SD=1.39) in their memory. Conclusions: The significant association between psychological factors and metamemory knowledge accuracy suggests that such characteristics may be important to consider in the conceptualization, assessment, and treatment of metacognitive disturbances. (JINS, 2018, 24, 498–510)
Precision farming advances are providing opportunities in both production agriculture and agricultural research. For growers and agronomists, the benefits of identifying where crops are stressed, the location of weeds and estimating yields on a large scale are clear. Researchers, who have different needs, can benefit from a detailed focus on a specific characteristic, such as one disease (e.g. yellow rust). This paper will review how recent advances in technology are beginning to allow the development of specialised tools within research and agriculture and how current precision agriculture tools can be effective at measuring desirable traits.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
Introduction: Patients with low-acuity (CTAS level IV and V) complaints often use the emergency department (ED) to access care. This has often been attributed to lack of a primary care (PC) provider. However, simply being registered with a primary care practitioner may not prevent low acuity ED presentation. There is some evidence that a lack of timely access to primary care may contribute to low acuity ED presentations. The Wait Time Alliance, a group of Canadian physicians and their respective professional associations, has recently set a benchmark of same day access to family doctors. It is unclear if this benchmark has been achieved in all jurisdictions. Methods: We performed linked cross sectional surveys to quantify the number of people presenting to a tertiary hospital ED (with 56,000 annual visits) with non-urgent problems who felt unable to access PC. PC practices were also surveyed to assess access using the metric of time to third next available appointment. Sample size calculations were completed. Descriptive statistics were reported. Results: In the patient survey, 381 of 580 patients consented to participate. Of those, 89 patients met eligibility criteria. 32 (35.9%) reported that the wait to see their PC provider was “too long”. 45 (50.5%) patients did not contact their PC office prior to ED presentation. 46 of 72 PC physician surveys were returned; a response rate of 63.8%. The mean time to third next available appointment in the region was 7.7 (95% CI 4.9-10.5) days (median 5 days, range 0-50 days). Conclusion: Fifty percent of low acuity patients did not attempt to access their PC provider prior to ED presentation. The benchmark of same day access to primary care has not been achieved in many practices in this region. Initiatives to promote primary care access would benefit both patients and providers.
Introduction: Patient morbidity and mortality are influenced by delay in access to care and lack of continuity of care. Patients frequently present to the emergency department (ED) for care despite being registered with a primary care (PC) provider. Advanced access is an open scheduling system promoted by the College of Family Physicians of Canada that triages primary care (PC) patients to be seen within 24 hours, reducing care delay. We wished to determine the prevalence of formal triage systems in PC appointment allocation. Methods: We performed linked cross sectional surveys to quantify the number of ambulatory patients presenting to a tertiary urban ED (with an annual census of 56,000 visits) who felt unable to access primary care. PC practices were also surveyed to assess use of formal triage methods and measure access using the metric of time to third next available appointment. Descriptive statistics were calculated. Results: In the patient survey, 381 of 580 patients consented to participate. Of those, 324 patients reported reasons for their ED visit. Perception that wait time for PC was “too long” was reported in 73/324 (23%); 86% reported wait times of greater than 48 hours. The PC practice response rate was 63.8% (46/ 72). The mean time to third next available appointment was 7.7 (95% CI 4.9-10.5) days (median 5 days, range 0-50 days). No PC practice reported utilizing a formal triage system when booking appointments. Conclusion: No primary care practices in the surveyed region used a formal triage system to allocate appointments, despite a range of wait times that extended up to 50 days. The safety of primary care appointment allocation may be improved with introduction of a formal triage system, especially if overall wait times cannot be reduced.
We present preliminary results from a programme designed to produce deep images of radio source fields drawn from the Parkes 2700 MHz and Molongolo 408 MHz catalogues using the charge-coupled-device (CCD) camera system built at the Institute of Astronomy, Cambridge. The programme is directed at a search both for faint extensions and nebulosity around radio QSOs and BL Lac objects and for faint objects in otherwise empty radio source fields; a detailed examination of the morphology of selected radio galaxies is also included.
A hallmark symptom after psychological trauma is the presence of intrusive memories. It is unclear why only some moments of trauma become intrusive, and how these memories involuntarily return to mind. Understanding the neural mechanisms involved in the encoding and involuntary recall of intrusive memories may elucidate these questions.
Participants (n = 35) underwent functional magnetic resonance imaging (fMRI) while being exposed to traumatic film footage. After film viewing, participants indicated within the scanner, while undergoing fMRI, if they experienced an intrusive memory of the film. Further intrusive memories in daily life were recorded for 7 days. After 7 days, participants completed a recognition memory test. Intrusive memory encoding was captured by comparing activity at the time of viewing ‘Intrusive scenes’ (scenes recalled involuntarily), ‘Control scenes’ (scenes never recalled involuntarily) and ‘Potential scenes’ (scenes recalled involuntarily by others but not that individual). Signal change associated with intrusive memory involuntary recall was modelled using finite impulse response basis functions.
We found a widespread pattern of increased activation for Intrusive v. both Potential and Control scenes at encoding. The left inferior frontal gyrus and middle temporal gyrus showed increased activity in Intrusive scenes compared with Potential scenes, but not in Intrusive scenes compared with Control scenes. This pattern of activation persisted when taking recognition memory performance into account. Intrusive memory involuntary recall was characterized by activity in frontal regions, notably the left inferior frontal gyrus.
The left inferior frontal gyrus may be implicated in both the encoding and involuntary recall of intrusive memories.
The contribution of education and intelligence to resilience against
age-related cognitive decline is not clear, particularly in the presence
of ‘normal for age’ minor brain abnormalities.
Participants (n = 208, mean age 69.2 years, s.d. = 5.4)
in the Whitehall II imaging substudy attended for neuropsychological
testing and multisequence 3T brain magnetic resonance imaging. Images
were independently rated by three trained clinicians for global and
hippocampal atrophy, periventricular and deep white matter changes.
Although none of the participants qualified for a clinical diagnosis of
dementia, a screen for cognitive impairment (Montreal Cognitive
Assessment (MoCA) <26) was abnormal in 22%. Hippocampal atrophy, in
contrast to other brain measures, was associated with a reduced MoCA
score even after controlling for age, gender, socioeconomic status, years
of education and premorbid IQ. Premorbid IQ and socioeconomic status were
associated with resilience in the presence of hippocampal atrophy.
Independent contributions from a priori risk (age,
hippocampal atrophy) and resilience (premorbid function, socioeconomic
status) combine to predict measured cognitive impairment.
We detail the influence of tapered interfaces on the nanoscale morphologies of ion-doped poly(styrene-b-oligo-oxyethylene methacrylate) block polymers (BPs). Most significantly, the location of double-gyroid network phase window was found in ion-doped normal-tapered materials, and a similar window was not detectable in the corresponding non-tapered and inverse-tapered BPs. Additionally, the effective interaction parameters, χeff, were reduced substantially in the tapered materials in comparison with their non-tapered counterparts. Overall, this work demonstrates that tapering between polymer blocks provides unique control over BP morphologies and improves the material processability (due to lower χeff), potentially facilitating the development of future ion-conducting devices.
Hypertension is associated with an increased risk of dementia and
depression with uncertain longitudinal associations with brain
To examine lifetime blood pressure as a predictor of brain structure in
A total of 190 participants (mean age 69.3 years) from the Whitehall II
study were screened for hypertension six times (1985–2013). In 2012–2013,
participants had a 3T-magnetic resonance imaging (MRI) brain scan. Data
from the MRI were analysed using automated and visual measures of global
atrophy, hippocampal atrophy and white matter hyperintensities.
Longitudinally, higher mean arterial pressure predicted increased
automated white matter hyperintensities (P<0.002).
Cross-sectionally, hypertensive participants had increased automated
white matter hyperintensities and visually rated deep white matter
hyperintensities. There was no significant association with global or
Long-term exposure to high blood pressure predicts hyperintensities,
particularly in deep white matter. The greatest changes are seen in those
with severe forms of hypertension, suggesting a dose–response
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a major wheat disease that can inflict yield losses of up to 70% on susceptible varieties under favourable environmental conditions. The timely identification of plant genetic resources likely to possess novel resistance to this disease would facilitate the rapid development of resistant wheat varieties. The focused identification of germplasm strategy (FIGS) approach was used to predict stripe rust resistance in a collection of wheat landraces conserved at ICARDA genebank. Long-term climate data for the collection sites, from which these accessions originated and stripe rust evaluation scores for one group of accessions were presented to three different non-linear models to explore the trait×collection site environment interactions. Patterns in the data detected by the models were used to predict stripe rust resistance in a second and different set of accessions. The results of the prediction were then tested against actual evaluation scores of the disease in the field. The study mimics the real scenario where requests are made to plant genetic resources curators to provide accessions that are likely to possess variation for specific traits such as disease resistance.
The models used were able to identify stripe rust-resistant accessions with a high degree of accuracy. Values as high as 0·75 for area under the curve and 0·45 for Kappa statistics, which quantify the agreement between the models’ predictions and the curator's disease scores, were achieved. This demonstrates a strong environmental component in the geographic distribution of resistance genes and therefore supports the theoretical basis for FIGS. It is argued that FIGS will improve the rate of gene discovery and efficiency of mining genetic resource collections for adaptive traits by reducing the number of accessions that are normally required for evaluation to identify such variation.
Major depression is associated with abnormalities in the function and structure of the hippocampus. However, it is unclear whether these abnormalities might also be present in people ‘at risk’ of illness.
We studied 62 young people (mean age 18.8 years) at familial risk of depression (FH+) but who had never been depressed themselves. Participants underwent magnetic resonance imaging to assess hippocampal structure and neural responses to a task designed to activate hippocampal memory networks. Magnetic resonance spectroscopy was used to measure levels of a combination of glutamine and glutamate (Glx) in the right hippocampus. A total of 59 matched controls with no history of mood disorder in a first-degree relative underwent the same investigations.
Hippocampal volume did not differ between FH+ participants and controls; however, relative to controls, during the memory task, FH+ participants showed increased activation in brain regions encompassing the insular cortices, putamen and pallidum as well as the dorsal anterior cingulate cortex (ACC). FH+ participants also had increased hippocampal levels of Glx.
Euthymic individuals with a parental history of depression demonstrate increased activation of hippocampal-related neural networks during a memory task, particularly in brain regions involved in processing the salience of stimuli. Changes in the activity of the ACC replicate previous findings in FH+ participants using different psychological tasks; this suggests that task-related abnormalities in the ACC may be a marker of vulnerability to depression. Increased levels of Glx in the hippocampus might also represent a risk biomarker but follow-up studies will be required to test these various possibilities.
The evidence is conflicting as to whether body mass index (BMI) is associated with mental health and, if so, to what extent it varies by sex and age. We studied mental health across the full spectrum of BMI among the general population, and conducted subgroup analyses by sex and age.
We undertook a cross-sectional study of a representative sample of the Scottish adult population. The Scottish Health Survey provided data on mental health, measured by the General Health Questionnaire-12 (GHQ), BMI, demographic and life-style information. Good mental health was defined as a GHQ score <4, and poor mental health as a GHQ score ⩾4. Logistic regression models were applied.
Of the 37 272 participants, 5739 (15.4%) had poor mental health. Overall, overweight participants had better mental health than the normal-weight group [adjusted odds ratio (OR) 0.93, 95% confidence interval (CI) 0.87–0.99, p = 0.049], and individuals who were underweight, class II or class III obese had poorer mental health (class III obese group: adjusted OR 1.26, 95% CI 1.05–1.51, p = 0.013). There were significant interactions of BMI with sex (p = 0.013) and with age (p < 0.001). Being overweight was associated with significantly better mental health in middle-aged men only. In contrast, being underweight at all ages or obese at a young age was associated with significantly poorer mental health in women only.
The adverse associations between adiposity and mental health are specific to women. Underweight women and young women who are obese have poorer mental health. In contrast, middle-aged overweight men have better mental health.