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Unlike for many other respiratory infections, the seasonality of pertussis is not well understood. While evidence of seasonal fluctuations in pertussis incidence has been noted in some countries, there have been conflicting findings including in the context of Australia. We investigated this issue by analysing the seasonality of pertussis notifications in Australia using monthly data from January 1991 to December 2016. Data were made available for all states and territories in Australia except for the Australian Capital Territory and were stratified into age groups. Using a time-series decomposition approach, we formulated a generalised additive model where seasonality is expressed using cosinor terms to estimate the amplitude and peak timing of pertussis notifications in Australia. We also compared these characteristics across different jurisdictions and age groups. We found evidence that pertussis notifications exhibit seasonality, with peaks observed during the spring and summer months (November–January) in Australia and across different states and territories. During peak months, notifications are expected to increase by about 15% compared with the yearly average. Peak notifications for children <5 years occurred 1–2 months later than the general population, which provides support to the theory that older household members remain an important source of pertussis infection for younger children. In addition, our results provide a more comprehensive spatial picture of seasonality in Australia, a feature lacking in previous studies. Finally, our findings suggest that seasonal forcing may be useful to consider in future population transmission models of pertussis.
Community-acquired pneumonia (CAP) results in substantial numbers of hospitalisations and deaths in older adults. There are known lifestyle and medical risk factors for pneumococcal disease but the magnitude of the additional risk is not well quantified in Australia. We used a large population-based prospective cohort study of older adults in the state of New South Wales (45 and Up Study) linked to cause-specific hospitalisations, disease notifications and death registrations from 2006 to 2015. We estimated the age-specific incidence of CAP hospitalisation (ICD-10 J12-18), invasive pneumococcal disease (IPD) notification and presumptive non-invasive pneumococcal CAP hospitalisation (J13 + J18.1, excluding IPD), comparing those with at least one risk factor to those with no risk factors. The hospitalised case-fatality rate (CFR) included deaths in a 30-day window after hospitalisation. Among 266 951 participants followed for 1 850 000 person-years there were 8747 first hospitalisations for CAP, 157 IPD notifications and 305 non-invasive pneumococcal CAP hospitalisations. In persons 65–84 years, 54.7% had at least one identified risk factor, increasing to 57.0% in those ⩾85 years. The incidence of CAP hospitalisation in those ⩾65 years with at least one risk factor was twofold higher than in those without risk factors, 1091/100 000 (95% confidence interval (CI) 1060–1122) compared with 522/100 000 (95% CI 501–545) and IPD in equivalent groups was almost threefold higher (18.40/100 000 (95% CI 14.61–22.87) vs. 6.82/100 000 (95% CI 4.56–9.79)). The CFR increased with age but there were limited difference by risk status, except in those aged 45 to 64 years. Adults ⩾65 years with at least one risk factor have much higher rates of CAP and IPD suggesting that additional risk factor-based vaccination strategies may be cost-effective.
During the summer of 2016, the Hawaii Department of Health responded to the second-largest domestic foodborne hepatitis A virus (HAV) outbreak in the post-vaccine era. The epidemiological investigation included case finding and investigation, sequencing of RNA positive clinical specimens, product trace-back and virologic testing and sequencing of HAV RNA from the product. Additionally, an online survey open to all Hawaii residents was conducted to estimate baseline commercial food consumption. We identified 292 confirmed HAV cases, of whom 11 (4%) were possible secondary cases. Seventy-four (25%) were hospitalised and there were two deaths. Among all cases, 94% reported eating at Oahu or Kauai Island branches of Restaurant Chain A, with 86% of those cases reporting raw scallop consumption. In contrast, a food consumption survey conducted during the outbreak indicated 25% of Oahu residents patronised Restaurant Chain A in the 7 weeks before the survey. Product trace-back revealed a single distributor that supplied scallops imported from the Philippines to Restaurant Chain A. Recovery, amplification and sequence comparison of HAV recovered from scallops revealed viral sequences matching those from case-patients. Removal of product from implicated restaurants and vaccination of those potentially exposed led to the cessation of the outbreak. This outbreak further highlights the need for improved imported food safety.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Objectives: Agenesis of the corpus callosum (AgCC), characterized by developmental absence of the corpus callosum, is one of the most common congenital brain malformations. To date, there are limited data on the neuropsychological consequences of AgCC and factors that modulate different outcomes, especially in children. This study aimed to describe general intellectual, academic, executive, social and behavioral functioning in a cohort of school-aged children presenting for clinical services to a hospital and diagnosed with AgCC. The influences of age, social risk and neurological factors were examined. Methods: Twenty-eight school-aged children (8 to 17 years) diagnosed with AgCC completed tests of general intelligence (IQ) and academic functioning. Executive, social and behavioral functioning in daily life, and social risk, were estimated from parent and teacher rated questionnaires. MRI findings reviewed by a pediatric neurologist confirmed diagnosis and identified brain characteristics. Clinical details including the presence of epilepsy and diagnosed genetic condition were obtained from medical records. Results: In our cohort, ~50% of children experienced general intellectual, academic, executive, social and/or behavioral difficulties and ~20% were functioning at a level comparable to typically developing children. Social risk was important for understanding variability in neuropsychological outcomes. Brain anomalies and complete AgCC were associated with lower mathematics performance and poorer executive functioning. Conclusions: This is the first comprehensive report of general intellectual, academic, executive social and behavioral consequences of AgCC in school-aged children. The findings have important clinical implications, suggesting that support to families and targeted intervention could promote positive neuropsychological functioning in children with AgCC who come to clinical attention. (JINS, 2018, 24, 445–455)
In ewe lambs, acceleration of growth and accumulation of both muscle and fat leads to earlier sexual maturity and better reproductive performance. The next stage in the development of this theme is to test whether these aspects of growth in young ewes affect milk production in their first lactation and the growth of their first progeny. We studied 75 young Merino ewes that had known phenotypic values for depth of eye muscle (EMD) and fat (FAT), and known Australian Sheep Breeding Values for post-weaning weight (PWT) and depths of eye muscle (PEMD) and fat (PFAT). They lambed for the first time at 1 year of age. Their lambs were weighed weekly from birth to weaning at 10 weeks to determine live weight gain and weaning weight. Progeny birth weight was positively associated with live weight gain and weaning weight (P<0.001). The PWT of the mothers was positively associated with birth weight (P<0.01), live weight gain and weaning weight of the progeny (P<0.05); however, these progeny traits were not influenced by EMD, FAT, PEMD, PFAT of the mothers (P>0.05). The PWT of the sire was positively associated with live weight gain (P<0.05) and weaning weight of the progeny (P<0.01). At around day 20 postpartum, we measured milk production and milk composition (fat, protein, lactose, total solids). Milk production was influenced positively by birth type (single or twin; P<0.05) and negatively by birth weight (P<0.05), but not by mother phenotype or genotype, sire genotype of the mother or the sex of the progeny (P>0.05). The concentrations of fat, protein, lactose and total solids in the milk were not affected by the phenotype or genotype of the mothers or of the sires of the mothers, or by the sex of the progeny (P>0.05). We conclude that selection of young Merino ewes for better growth, and more rapid accumulation of muscle and fat, will lead to progeny that are heavier at birth, grow faster and are heavier at weaning. Moreover, milk production and composition do not seem to be affected by the genetic merit of the mother for post-weaning live weight or PEMD or PFAT. Therefore, Merino ewes can lamb at 1 year of age without affecting the production objectives of the Merino sheep industry.
The solar magnesium II core-to-wing ratio has been a well-studied proxy for chromospheric activity since 1978. Daily measurements at high spectral (0.1 nm) resolution began with the launch of the Solar Radiation and Climate Experiment (SORCE) in 2003. The next generation of measurements from the Extreme Ultraviolet Sensor (EUVS) on the Geostationary Operational Environmental Satellite 16 (GOES-16) will add high time cadence (every 30 seconds) to the observational Mg II irradiance record. We present a comparison of the two measurements during the period of overlap.
Ultraviolet (UV) Solar spectral Irradiance (SSI) has been measured from orbit on a regular basis since the beginning of the space age. These observations span four Solar Cycles, and they are crucial for our understanding of the Sun-Earth connection and space weather. SSI at these wavelengths are the main drivers for the upper atmosphere including the production and destruction of ozone in the stratosphere. The instruments that measure UV SSI not only require good preflight calibration, but also need a robust method to maintain that calibration on orbit. We will give an overview of the catalog of current and former UV SSI measurements along with the calibration philosophy of each instrument and an estimation of the uncertainties in the published irradiances.
Palmer amaranth control has become a major challenge for multiple cropping systems across the southeastern and midwestern United States. Despite extensive research on herbicide-resistance evolution, little research has been done exploring how Palmer amaranth might also be evolving other adaptive traits in response to different selection forces present in agricultural fields and the enrichment of soils with nutrients such as nitrogen. The objective of the present study was to determine whether Palmer amaranth populations have evolved different morphology and growth patterns in response to glyphosate use and fertilization history. Ten Palmer amaranth populations, including glyphosate-resistant (GR) and glyphosate-susceptible (GS) populations, were collected from different cropping systems with histories of high and low nitrogen fertilization in the states of Florida and Georgia. All populations were grown in pots filled with soil fertilized with either 0 or 40 kgNha−1, and their response to nitrogen was compared for morphological, growth, and nutrient-use traits. Populations differed in how they modified their morphology and growth in response to N, with major differences in traits such as foliar area, branch production, leaf shape, and canopy architecture. Populations with high nitrogen-fertilization histories had higher (>43%) nutrient-use efficiency (NUE) than populations with low nitrogen-fertilization histories. Similarly, GR populations have evolved higher NUE (>47%) and changed canopy architecture more than GS populations in response to nitrogen fertilization. The results of the present study highlight the importance of paying more attention to adaptations to cultural practices that might increase weediness and how genetic changes in traits involved in morphology and metabolism might favor compensatory mechanisms increasing the fitness of the population carrying herbicide-resistant traits.
Cognitive deficits are a core feature of schizophrenia, and impairments in most domains are thought to be stable over the course of the illness. However, cross-sectional evidence indicates that some areas of cognition, such as visuospatial associative memory, may be preserved in the early stages of psychosis, but become impaired in later established illness stages. This longitudinal study investigated change in visuospatial and verbal associative memory following psychosis onset.
In total 95 first-episode psychosis (FEP) patients and 63 healthy controls (HC) were assessed on neuropsychological tests at baseline, with 38 FEP and 22 HCs returning for follow-up assessment at 5–11 years. Visuospatial associative memory was assessed using the Cambridge Neuropsychological Test Automated Battery Visuospatial Paired-Associate Learning task, and verbal associative memory was assessed using Verbal Paired Associates subtest of the Wechsler Memory Scale - Revised.
Visuospatial and verbal associative memory at baseline did not differ significantly between FEP patients and HCs. However, over follow-up, visuospatial associative memory deteriorated significantly for the FEP group, relative to healthy individuals. Conversely, verbal associative memory improved to a similar degree observed in HCs. In the FEP cohort, visuospatial (but not verbal) associative memory ability at baseline was associated with functional outcome at follow-up.
Areas of cognition that develop prior to psychosis onset, such as visuospatial and verbal associative memory, may be preserved early in the illness. Later deterioration in visuospatial memory ability may relate to progressive structural and functional brain abnormalities that occurs following psychosis onset.
Palmer amaranth’s ability to evolve resistance to different herbicides has been studied extensively, but there is little information about how this weed species might be evolving other life-history traits that could potentially make it more aggressive and difficult to control. We characterized growth and morphological variation among 10 Palmer amaranth populations collected in Florida and Georgia from fields with different cropping histories, ranging from continuous short-statured crops (vegetables and peanut) to tall crops (corn and cotton) and from intensive herbicide use history to organic production. Palmer amaranth populations differed in multiple traits such as fresh and dry weight, days to flowering, plant height, and leaf and canopy shape. Differences between populations for these traits ranged from 36% up to 87%. Although glyphosate-resistant (GR) populations collected from cropping systems including GR crops exhibited higher values of the aforementioned variables than glyphosate-susceptible (GS) populations, variation in traits was not explained by glyphosate resistance or distance between populations. Cropping system components such as crop rotation and crop canopy structure better explained the differences among populations. The higher growth of GR populations compared with GS populations was likely the result of multiple selection forces present in the cropping systems in which they grow rather than a pleiotropic effect of the glyphosate resistance trait. Results suggest that Palmer amaranth can evolve life-history traits increasing its growth and reproduction potential in cropping systems, which explains its rapid spread throughout the United States. Furthermore, our findings highlight the need to consider the evolutionary consequences of crop rotation structure and the use of more competitive crops, which might promote the selection of more aggressive biotypes in weed species with high genetic variability.
To prospectively assess treatment outcomes of chronic rhinosinusitis patients undergoing functional endoscopic sinus surgery and post-operative medical treatment over a prolonged follow-up period.
Patients undergoing functional endoscopic sinus surgery in the tertiary referral practice of a single surgeon were studied prospectively. Symptoms were scored by patients pre-operatively and over a minimum follow-up period of 12 months.
The study comprised 200 non-consecutive patients. The median pre-operative symptom score was 16 (out of a maximum of 25) (95 per cent confidence interval = 15 to 17). Symptom scores reduced to a median of 7 (95 per cent confidence interval = 6 to 8) after 12 months of follow up (p < 0.0001). The median symptom score improved for all symptoms and across all patient subgroups.
Extensive functional endoscopic sinus surgery offers significant and durable symptom improvement in patients with chronic rhinosinusitis refractory to medical treatment. This improvement extends to all patient subgroups. Prolonged medical therapy is recommended after functional endoscopic sinus surgery.
The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.
We sought to conduct a major objective of the CAEP Academic Section, an environmental scan of the academic emergency medicine programs across the 17 Canadian medical schools.
We developed an 84-question questionnaire, which was distributed to academic heads. The responses were validated by phone by the lead author to ensure that the questions were answered completely and consistently. Details of pediatric emergency medicine units were excluded from the scan.
At eight of 17 universities, emergency medicine has full departmental status and at two it has no official academic status. Canadian academic emergency medicine is practiced at 46 major teaching hospitals and 13 specialized pediatric hospitals. Another 69 Canadian hospital EDs regularly take clinical clerks and emergency medicine residents. There are 31 full professors of emergency medicine in Canada. Teaching programs are strong with clerkships offered at 16/17 universities, CCFP(EM) programs at 17/17, and RCPSC residency programs at 14/17. Fourteen sites have at least one physician with a Master’s degree in education. There are 55 clinical researchers with salary support at 13 universities. Sixteen sites have published peer-reviewed papers in the past five years, ranging from four to 235 per site. Annual budgets range from $200,000 to $5,900,000.
This comprehensive review of academic activities in emergency medicine across Canada identifies areas of strengths as well as opportunities for improvement. CAEP and the Academic Section hope we can ultimately improve ED patient care by sharing best academic practices and becoming better teachers, educators, and researchers.
Salience network (SN) dysconnectivity has been hypothesized to contribute to schizophrenia. Nevertheless, little is known about the functional and structural dysconnectivity of SN in subjects at risk for psychosis. We hypothesized that SN functional and structural connectivity would be disrupted in subjects with At-Risk Mental State (ARMS) and would be associated with symptom severity and disease progression.
We examined 87 ARMS and 37 healthy participants using both resting-state functional magnetic resonance imaging and diffusion tensor imaging. Group differences in SN functional and structural connectivity were examined using a seed-based approach and tract-based spatial statistics. Subject-level functional connectivity measures and diffusion indices of disrupted regions were correlated with CAARMS scores and compared between ARMS with and without transition to psychosis.
ARMS subjects exhibited reduced functional connectivity between the left ventral anterior insula and other SN regions. Reduced fractional anisotropy (FA) and axial diffusivity were also found along white-matter tracts in close proximity to regions of disrupted functional connectivity, including frontal-striatal-thalamic circuits and the cingulum. FA measures extracted from these disrupted white-matter regions correlated with individual symptom severity in the ARMS group. Furthermore, functional connectivity between the bilateral insula and FA at the forceps minor were further reduced in subjects who transitioned to psychosis after 2 years.
Our findings support the insular dysconnectivity of the proximal SN hypothesis in the early stages of psychosis. Further developed, the combined structural and functional SN assays may inform the prognosis of persons at-risk for psychosis.
Following a successful program to investigate the physics of ultra-high-pressure proportional counters, a counter array has been developed for hard X-ray astronomy. A parallel investigation has evaluated the performance of a large-area phoswich scintillator detector for the same purpose. The two detectors have been integrated in a balloon-borne payload, the Astrophysical X-ray Experimental Laboratory (AXEL). This paper describes the instrumentation aboard the payload.
Several outbreaks of hepatitis A in men who have sex with men (MSM) were reported in the 1980s and 1990s in Australia and other countries. An effective hepatitis A virus (HAV) vaccine has been available in Australia since 1994 and is recommended for high-risk groups including MSM. No outbreaks of hepatitis A in Australian MSM have been reported since 1996. In this study, we aimed to estimate HAV transmissibility in MSM populations in order to inform targets for vaccine coverage in such populations. We used mathematical models of HAV transmission in a MSM population to estimate the basic reproduction number (R0) and the probability of an HAV epidemic occurring as a function of the immune proportion. We estimated a plausible range for R0 of 1·71–3·67 for HAV in MSM and that sustained epidemics cannot occur once the proportion immune to HAV is greater than ~70%. To our knowledge this is the first estimate of R0 and the critical population immunity threshold for HAV transmission in MSM. As HAV is no longer endemic in Australia or in most other developed countries, vaccination is the only means of maintaining population immunity >70%. Our findings provide impetus to promote HAV vaccination in high-risk groups such as MSM.
Major depressive disorder (MDD) is a common and disabling condition with well-established heritability and environmental risk factors. Gene–environment interaction studies in MDD have typically investigated candidate genes, though the disorder is known to be highly polygenic. This study aims to test for interaction between polygenic risk and stressful life events (SLEs) or childhood trauma (CT) in the aetiology of MDD.
The RADIANT UK sample consists of 1605 MDD cases and 1064 controls with SLE data, and a subset of 240 cases and 272 controls with CT data. Polygenic risk scores (PRS) were constructed using results from a mega-analysis on MDD by the Psychiatric Genomics Consortium. PRS and environmental factors were tested for association with case/control status and for interaction between them.
PRS significantly predicted depression, explaining 1.1% of variance in phenotype (p = 1.9 × 10−6). SLEs and CT were also associated with MDD status (p = 2.19 × 10−4 and p = 5.12 × 10−20, respectively). No interactions were found between PRS and SLEs. Significant PRSxCT interactions were found (p = 0.002), but showed an inverse association with MDD status, as cases who experienced more severe CT tended to have a lower PRS than other cases or controls. This relationship between PRS and CT was not observed in independent replication samples.
CT is a strong risk factor for MDD but may have greater effect in individuals with lower genetic liability for the disorder. Including environmental risk along with genetics is important in studying the aetiology of MDD and PRS provide a useful approach to investigating gene–environment interactions in complex traits.
To characterize the current state of Canadian emergency medicine (EM) resident research and develop recommendations to promote excellence in this area.
We performed a systematic review of MEDLINE, Embase, and ERIC using search terms relevant to EM resident research. We conducted an online survey of EM residency program directors from the Royal College of Physicians and Surgeons of Canada (RCPSC) and College of Family Physicians of Canada (CFPC). An expert panel reviewed these data, presented recommendations at the Canadian Association of Emergency Physicians 2014 Academic Symposium, and refined them based on feedback received.
Of 654 potentially relevant citations, 35 articles were included. These were categorized into four themes: 1) expectations and requirements, 2) training and assessment, 3) infrastructure and support, and 4) dissemination. We received 31 responses from all 31 RCPSC-EM and CFPC-EM programs. The majority of EM programs reported requiring a resident scholarly project; however, we found wide-ranging expectations for the type of resident research performed and how results were disseminated, as well as the degree of completion expected. Although 93% of RCPSC-EM programs reported providing formal training on how to conduct research, only 53% of CFPC-EM programs reported doing so. Almost all programs (94%) reported having infrastructure in place to support resident research, but the nature of support was highly variable. Finally, there was marked variability regarding the number of resident-published abstracts and manuscripts.
Based on the literature, our national survey, and discussions with stakeholders, we offer 14 recommendations encompassing goals, expectations, training, assessment, infrastructure, and dissemination in order to improve Canadian EM resident research.