To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Toxoplasma gondii (T. gondii) is an important human disease-causing parasite. In the USA, T. gondii infects >10% of the population, accrues economic losses of US$3.6 billion/year, and ranks as the second leading culprit of foodborne illness-related fatalities. We assessed toxoplasmosis risk among the Old Order Amish, a mostly homogenous population with a high prevalence of T. gondii seropositivity, using a questionnaire focusing on food consumption/preparation behaviours and environmental risk factors. Analyses were conducted using multiple logistic regression. Consuming raw meat, rare meat, or unpasteurised cow or goat milk products was associated with increased odds of seropositivity (unadjusted Odds Ratios: 2.192, 1.613, and 1.718 , respectively). In separate models by sex, consuming raw meat, or consuming unpasteurised cow or goat milk products, was associated with increased odds of seropositivity among women; washing hands after touching meat with decreased odds of seropositivity among women (adjusted OR (AOR): 0.462); and cleaning cat litterbox with increased odds of seropositivity among men (AOR: 5.241). This is the first study to assess associations between behavioural and environmental risk factors and T. gondii seropositivity in a US population with high seroprevalence for T. gondii. Our study emphasises the importance of proper food safety behaviours to avoid the risk of infection.
Bipolar disorder (BD) is a familial psychiatric disorder associated with frontotemporal and subcortical brain abnormalities. It is unclear whether such abnormalities are present in relatives without BD, and little is known about structural brain trajectories in those at risk.
Neuroimaging was conducted at baseline and at 2-year follow-up interval in 90 high-risk individuals with a first-degree BD relative (HR), and 56 participants with no family history of mental illness who could have non-BD diagnoses. All 146 subjects were aged 12–30 years at baseline. We examined longitudinal change in gray and white matter volume, cortical thickness, and surface area in the frontotemporal cortex and subcortical regions.
Compared to controls, HR participants showed accelerated cortical thinning and volume reduction in right lateralised frontal regions, including the inferior frontal gyrus, lateral orbitofrontal cortex, frontal pole and rostral middle frontal gyrus. Independent of time, the HR group had greater cortical thickness in the left caudal anterior cingulate cortex, larger volume in the right medial orbitofrontal cortex and greater area of right accumbens, compared to controls. This pattern was evident even in those without the new onset of psychopathology during the inter-scan interval.
This study suggests that differences previously observed in BD are developing prior to the onset of the disorder. The pattern of pathological acceleration of cortical thinning is likely consistent with a disturbance of molecular mechanisms responsible for normal cortical thinning. We also demonstrate that neuroanatomical differences in HR individuals may be progressive in some regions and stable in others.
To make a power spectrum (PS) detection of the 21-cm signal from the Epoch of Reionisation (EoR), one must avoid/subtract bright foreground sources. Sources such as Fornax A present a modelling challenge due to spatial structures spanning from arc seconds up to a degree. We compare modelling with multi-scale (MS) CLEAN components to ‘shapelets’, an alternative set of basis functions. We introduce a new image-based shapelet modelling package, SHAMFI. We also introduce a new CUDA simulation code (WODEN) to generate point source, Gaussian, and shapelet components into visibilities. We test performance by modelling a simulation of Fornax A, peeling the model from simulated visibilities, and producing a residual PS. We find the shapelet method consistently subtracts large-angular-scale emission well, even when the angular resolution of the data is changed. We find that when increasing the angular resolution of the data, the MS CLEAN model worsens at large angular scales. When testing on real Murchison Widefield Array data, the expected improvement is not seen in real data because of the other dominating systematics still present. Through further simulation, we find the expected differences to be lower than obtainable through current processing pipelines. We conclude shapelets are worthwhile for subtracting extended galaxies, and may prove essential for an EoR detection in the future, once other systematics have been addressed.
To outline features of the neurologic examination that can be performed virtually through telemedicine platforms (the virtual neurological examination [VNE]), and provide guidance for rapidly pivoting in-person clinical assessments to virtual visits during the COVID-19 pandemic and beyond.
The full neurologic examination is described with attention to components that can be performed virtually.
A screening VNE is outlined that can be performed on a wide variety of patients, along with detailed descriptions of virtual examination maneuvers for specific scenarios (cognitive testing, neuromuscular and movement disorder examinations).
During the COVID-19 pandemic, rapid adoption of virtual medicine will be critical to provide ongoing and timely neurological care. Familiarity and mastery of a VNE will be critical for neurologists, and this article outlines a practical approach to implementation.
This project will work closely with existing service partners involved in street level services and focus on testing and evaluating three approaches for street level interventions for youth who are homeless and who have severe or moderate mentally illness. Youth will be asked to choose their preferred service approach:
Housing First related initiatives focused on interventions designed to move youth to appropriate and available housing and ongoing housing supports.
Treatment First initiatives to provide Mental Health/Addiction supports and treatment solutions, and; Simultaneous attention to both Housing and Treatment Together
Our primary objective is to understand the service delivery preferences of homeless youth and understand the outcomes of these choices. Our research questions include:
1. Which approaches to service are chosen by youth?
2. What are the differences and similarities between groups choosing each approach?
3. What are the critical ingredients needed to effectively implement services for homeless youth from the perspectives of youth, families and service providers?
Focus groups with staff and family members will occur to assist in understanding the nature of each of service approach, changes that evolve within services, & facilitators and barriers to service delivery. This work will be important in determining which approach is chosen by youth and why. Evaluating the outcomes with each choice will provide valuable information about outcomes for the service options chosen by youth. This assist in better identifying weaknesses in the services offered and inform further development of treatment options that youth will accept.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
Despite the magnitude and protracted nature of the Rohingya refugee situation, there is limited information on the culture, mental health and psychosocial wellbeing of this group. This paper, drawing on a report commissioned by the United Nations High Commissioner for Refugees (UNHCR), aims to provide a comprehensive synthesis of the literature on mental health and psychosocial wellbeing of Rohingya refugees, including an examination of associated cultural factors. The ultimate objective is to assist humanitarian actors and agencies in providing culturally relevant Mental Health and Psychosocial Support (MHPSS) for Rohingya refugees displaced to Bangladesh and other neighbouring countries.
We conducted a systematic search across multiple sources of information with reference to the contextual, social, economic, cultural, mental health and health-related factors amongst Rohingya refugees living in the Asia-Pacific and other regions. The search covered online databases of diverse disciplines (e.g. medicine, psychology, anthropology), grey literature, as well as unpublished reports from non-profit organisations and United Nations agencies published until 2018.
The legacy of prolonged exposure to conflict and persecution compounded by protracted conditions of deprivations and displacement is likely to increase the refugees' vulnerability to wide array of mental health problems including posttraumatic stress disorder, anxiety, depression and suicidal ideation. High rates of sexual and gender-based violence, lack of privacy and safe spaces and limited access to integrated psychosocial and mental health support remain issues of concern within the emergency operation in Bangladesh. Another challenge is the limited understanding amongst the MHPSS personnel in Bangladesh and elsewhere of the language, culture and help-seeking behaviour of Rohingya refugees. While the Rohingya language has a considerable vocabulary for emotional and behavioural problems, there is limited correspondence between these Rohingya terms and western concepts of mental disorders. This hampers the provision of culturally sensitive and contextually relevant MHPSS services to these refugees.
The knowledge about the culture, context, migration history, idioms of distress, help-seeking behaviour and traditional healing methods, obtained from diverse sources can be applied in the design and delivery of culturally appropriate interventions. Attention to past exposure to traumatic events and losses need to be paired with attention for ongoing stressors and issues related to worries about the future. It is important to design MHPSS interventions in ways that mobilise the individual and collective strengths of Rohingya refugees and build on their resilience.
Many women experience both vasomotor menopausal symptoms (VMS) and depressed mood at midlife, but little is known regarding the prospective bi-directional relationships between VMS and depressed mood and the role of sleep difficulties in both directions.
A pooled analysis was conducted using data from 21 312 women (median: 50 years, interquartile range 49−51) in eight studies from the InterLACE consortium. The degree of VMS, sleep difficulties, and depressed mood was self-reported and categorised as never, rarely, sometimes, and often (if reporting frequency) or never, mild, moderate, and severe (if reporting severity). Multivariable logistic regression models were used to examine the bi-directional associations adjusted for within-study correlation.
At baseline, the prevalence of VMS (40%, range 13–62%) and depressed mood (26%, 8–41%) varied substantially across studies, and a strong dose-dependent association between VMS and likelihood of depressed mood was found. Over 3 years of follow-up, women with often/severe VMS at baseline were more likely to have subsequent depressed mood compared with those without VMS (odds ratios (OR) 1.56, 1.27–1.92). Women with often/severe depressed mood at baseline were also more likely to have subsequent VMS than those without depressed mood (OR 1.89, 1.47–2.44). With further adjustment for the degree of sleep difficulties at baseline, the OR of having a subsequent depressed mood associated with often/severe VMS was attenuated and no longer significant (OR 1.13, 0.90–1.40). Conversely, often/severe depressed mood remained significantly associated with subsequent VMS (OR 1.80, 1.38–2.34).
Difficulty in sleeping largely explained the relationship between VMS and subsequent depressed mood, but it had little impact on the relationship between depressed mood and subsequent VMS.
We present techniques developed to calibrate and correct Murchison Widefield Array low-frequency (72–300 MHz) radio observations for polarimetry. The extremely wide field-of-view, excellent instantaneous (u, v)-coverage and sensitivity to degree-scale structure that the Murchison Widefield Array provides enable instrumental calibration, removal of instrumental artefacts, and correction for ionospheric Faraday rotation through imaging techniques. With the demonstrated polarimetric capabilities of the Murchison Widefield Array, we discuss future directions for polarimetric science at low frequencies to answer outstanding questions relating to polarised source counts, source depolarisation, pulsar science, low-mass stars, exoplanets, the nature of the interstellar and intergalactic media, and the solar environment.
The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target fields. In this paper, we develop a model for the compact foreground sources in one of the target fields of the MWA’s EoR key science experiment: the ‘EoR1’ field. The model is based on both the MWA’s GLEAM survey and GMRT 150 MHz data from the TGSS survey, the latter providing higher angular resolution and better astrometric accuracy for compact sources than is available from the MWA alone. The model contains 5 049 sources, some of which have complicated morphology in MWA data, Fornax A being the most complex. The higher resolution data show that 13% of sources that appear point-like to the MWA have complicated morphology such as double and quad structure, with a typical separation of 33 arcsec. We derive an analytic expression for the error introduced into the EoR two-dimensional power spectrum due to peeling close double sources as single point sources and show that for the measured source properties, the error in the power spectrum is confined to high k⊥ modes that do not affect the overall result for the large-scale cosmological signal of interest. The brightest 10 mis-modelled sources in the field contribute 90% of the power bias in the data, suggesting that it is most critical to improve the models of the brightest sources. With this hybrid model, we reprocess data from the EoR1 field and show a maximum of 8% improved calibration accuracy and a factor of two reduction in residual power in k-space from peeling these sources. Implications for future EoR experiments including the SKA are discussed in relation to the improvements obtained.
Despite the known heightened risk and burden of various somatic diseases in people with depression, very little is known about physical health multimorbidity (i.e. two or more physical health co-morbidities) in individuals with depression. This study explored physical health multimorbidity in people with clinical depression, subsyndromal depression and brief depressive episode across 43 low- and middle-income countries (LMICs).
Cross-sectional, community-based data on 190 593 individuals from 43 LMICs recruited via the World Health Survey were analysed. Multivariable logistic regression analysis was done to assess the association between depression and physical multimorbidity.
Overall, two, three and four or more physical health conditions were present in 7.4, 2.4 and 0.9% of non-depressive individuals compared with 17.7, 9.1 and 4.9% among people with any depressive episode, respectively. Compared with those with no depression, subsyndromal depression, brief depressive episode and depressive episode were significantly associated with 2.62, 2.14 and 3.44 times higher odds for multimorbidity, respectively. A significant positive association between multimorbidity and any depression was observed across 42 of the 43 countries, with particularly high odds ratios (ORs) in China (OR 8.84), Laos (OR 5.08), Ethiopia (OR 4.99), the Philippines (OR 4.81) and Malaysia (OR 4.58). The pooled OR for multimorbidity and depression estimated by meta-analysis across 43 countries was 3.26 (95% confident interval 2.98–3.57).
Our large multinational study demonstrates that physical health multimorbidity is increased across the depression spectrum. Public health interventions are required to address this global health problem.
We present new software to cross-match low-frequency radio catalogues: the Positional Update and Matching Algorithm. The Positional Update and Matching Algorithm combines a positional Bayesian probabilistic approach with spectral matching criteria, allowing for confusing sources in the matching process. We go on to create a radio sky model using Positional Update and Matching Algorithm based on the Murchison Widefield Array Commissioning Survey, and are able to automatically cross-match ~ 98.5% of sources. Using the characteristics of this sky model, we create simple simulated mock catalogues on which to test the Positional Update and Matching Algorithm, and find that Positional Update and Matching Algorithm can reliably find the correct spectral indices of sources, along with being able to recover ionospheric offsets. Finally, we use this sky model to calibrate and remove foreground sources from simulated interferometric data, generated using OSKAR (the Oxford University visibility generator). We demonstrate that there is a substantial improvement in foreground source removal when using higher frequency and higher resolution source positions, even when correcting positions by an average of 0.3 arcmin given a synthesised beam-width of ~ 2.3 arcmin.
A modification of the growth structure of Eu-doped GaN (GaN:Eu) from a monolayer to a multilayer structure (MLS) consisting of alternating GaN and GaN:Eu, was shown to enhance the emission properties. Similarly, lowering the growth temperature of the GaN:Eu to 960°C nearly doubled the photoluminescence emission intensity, and also enhanced device performance. Hence, to design a higher power GaN:Eu red LED, a multilayer structure consisting of 40 pairs of alternating GaN and GaN:Eu was grown at 960°C. This combination resulted in the fabrication of an LED with a maximum output power of 110 μW, which is 5.8 times more output power per GaN:Eu layer thickness as compared to the best previously reported device. Moreover, it was found that the MLS sample grown at 960°C maintained a high crystal quality with low surface roughness, which enabled an increase in the number of pairs from 40 pairs to 100 pairs. An MLS-LED consisting of 100 pairs of alternating GaN/GaN:Eu layers was successfully fabricated, and had a maximum output power of 375 μW with an external quantum efficiency of 4.6%. These are the highest values reported for this system.
Chronic suppurative otitis media is a neglected condition affecting up to 330 million people worldwide, with the burden of the disease in impoverished countries. The need for non-governmental organisations to hardwire training into their programmes has been highlighted. An ear surgery simulator appropriate for training in resource-poor settings was developed, and its effectiveness in facilitating the acquisition of headlight and microsurgical skills necessary to safely perform procedures via the ear canal was investigated.
Face validity was assessed via questionnaires. Six tasks were developed: a headlight foreign body removal task, and microscope tasks of foreign body removal, ventilation tube insertion, tympanomeatal flap raising, myringoplasty and middle-ear manipulation. Participants with varying ENT experience were video-recorded performing each task and scored by a blinded expert observer to assess construct validity.
Face validity results confirmed that our Ear Trainer was a realistic representation of the ear. Construct validity results showed a statistically significant trend, with experts performing the best and those with limited experience performing better than novices.
This study validates our Ear Trainer as a useful training tool for assessing headlight and microsurgical skills required to perform otological procedures.
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.
White matter (WM) impairments have been reported in patients with bipolar disorder (BD) and those at high familial risk of developing BD. However, the distribution of these impairments has not been well characterized. Few studies have examined WM integrity in young people early in the course of illness and in individuals at familial risk who have not yet passed the peak age of onset.
WM integrity was examined in 63 BD subjects, 150 high-risk (HR) individuals and 111 participants with no family history of mental illness (CON). All subjects were aged 12 to 30 years.
This young BD group had significantly lower fractional anisotropy within the genu of the corpus callosum (CC) compared with the CON and HR groups. Moreover, the abnormality in the genu of the CC was also present in HR participants with recurrent major depressive disorder (MDD) (n = 16) compared with CON participants.
Our findings provide important validation of interhemispheric abnormalities in BD patients. The novel finding in HR subjects with recurrent MDD – a group at particular risk of future hypo/manic episodes – suggests that this may potentially represent a trait marker for BD, though this will need to be confirmed in longitudinal follow-up studies.
We have compiled a catalogue of H ii regions detected with the Murchison Widefield Array between 72 and 231 MHz. The multiple frequency bands provided by the Murchison Widefield Array allow us identify the characteristic spectrum generated by the thermal Bremsstrahlung process in H ii regions. We detect 306 H ii regions between 260° < l < 340° and report on the positions, sizes, peak, integrated flux density, and spectral indices of these H ii regions. By identifying the point at which H ii regions transition from the optically thin to thick regime, we derive the physical properties including the electron density, ionised gas mass, and ionising photon flux, towards 61 H ii regions. This catalogue of H ii regions represents the most extensive and uniform low frequency survey of H ii regions in the Galaxy to date.
Post-traumatic stress disorder (PTSD) is associated with elevated risk for metabolic syndrome (MetS). However, the direction of this association is not yet established, as most prior studies employed cross-sectional designs. The primary goal of this study was to evaluate bidirectional associations between PTSD and MetS using a longitudinal design.
A total of 1355 male and female veterans of the conflicts in Iraq and Afghanistan underwent PTSD diagnostic assessments and their biometric profiles pertaining to MetS were extracted from the electronic medical record at two time points (spanning ~2.5 years, n = 971 at time 2).
The prevalence of MetS among veterans with PTSD was just under 40% at both time points and was significantly greater than that for veterans without PTSD; the prevalence of MetS among those with PTSD was also elevated relative to age-matched population estimates. Cross-lagged panel models revealed that PTSD severity predicted subsequent increases in MetS severity (β = 0.08, p = 0.002), after controlling for initial MetS severity, but MetS did not predict later PTSD symptoms. Logistic regression results suggested that for every 10 PTSD symptoms endorsed at time 1, the odds of a subsequent MetS diagnosis increased by 56%.
Results highlight the substantial cardiometabolic concerns of young veterans with PTSD and raise the possibility that PTSD may predispose individuals to accelerated aging, in part, manifested clinically as MetS. This demonstrates the need to identify those with PTSD at greatest risk for MetS and to develop interventions that improve both conditions.