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Studies that reveal detailed information about trilobite growth, particularly early developmental stages, are crucial for improving our understanding of the phylogenetic relationships within this iconic group of fossil arthropods. Here we document an essentially complete ontogeny of the trilobite Redlichia cf. versabunda from the Cambrian Series 2 (late Stage 4) Ramsay Limestone of Yorke Peninsula in South Australia, including some of the best-preserved protaspides (the earliest biomineralized trilobite larval stage) known for any Cambrian trilobite. These protaspid stages exhibit similar morphological characteristics to many other taxa within the Suborder Redlichiina, especially to closely related species such as Metaredlichia cylindrica from the early Cambrian period of China. Morphological patterns observed across early developmental stages of different groups within the Order Redlichiida are discussed. Although redlichiine protaspides exhibit similar overall morphologies, certain ontogenetic characters within this suborder have potential phylogenetic signal, with different superfamilies characterized by unique trait combinations in these early growth stages.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Stress and mental health problems is common among medical students, but we lack studies of intervention programmes during medical school.
Design and Methods
The students participated in one of two group session programmes during their third year at medical school. One option was a self-development programme delivered by trained group therapists. Alternatively the students chose a programme focusing on themes of special relevance to doctors. The format was one and a half hours' group sessions, once weekly, altogether 12 times. The baseline data were gathered before the intervention (T1).We studied the effect 3 months post intervention (T2), in this first follow-up paper. One class (N= 128) of medical students were given the group intervention programmes. The next year class (comparison group) received no intervention (N= 152). The main outcome of this study was Perceived Medical School Stress (PMSS), which has been linked to anxiety and depression, as well as need for treatment. We used multilevel linear model (repeated measures) to test for differences over time.
Both the intervention and the comparison groups showed a decline in PMSS from T1 to T2. There was an interaction between time and the intervention, and this indicates a significant effect (P=0.01) of the intervention. We found this effect due to the participation in the self-development groups (P=0.009). All effects were controlled for age and gender.
The self-development groups have a beneficial effect on stress among the students in a three months follow-up.
Effective preventive strategies could reduce disability and the long term social and health complications associated with depression, but options are limited. Cognitive bias modification (CBM) is a novel, simple, and safe intervention that corrects the attentional and interpretive biases associated with depression.
To determine if CBM decreases the one-year onset of major depression in adults at risk.
This randomised controlled trial will recruit adults with subsyndromal depression living in Australia (parallel design, 1:1 allocation ratio). The intervention will be delivered via the internet over 52 weeks. The primary outcome of interest is the onset of a major depression according to DSM-IV-TR criteria. Secondary outcomes of interest include change in the severity of depressive (Patient Health Questionnaire, PHQ-9) and changes in attention and interpretive biases. Outcomes will be collected 3, 6, 9 and 12 months after randomisation.
Preliminary data on a subsample of 20 participants showed that the mean±SE PHQ-9 score of controls was 7.5±0.9 at study entry and 7.1±1.5 at week 6 (paired t-test=0.29, p=0.779), whereas the mean±SE score of active CBM participants was 7.4±1.0 and 4.4±1.1, respectively (paired t=6.00, p<0.001). The mean PHQ-9 difference between control and active CBM participants over 6 weeks was 2.6±1.5 points (t=1.79, p=0.090). One of 11 controls (9.1%) and 0/9 active CBM participants showed evidence of clinically significant depressive symptoms at week 6 (i.e., PHQ-9≥15).
By March 2015, 6-months preliminary data will be available on 165 participants.
Twelve evidence-based profiles of roles across the translational workforce and two patients were made available through clinical and translational science (CTS) Personas, a project of the Clinical and Translational Science Awards (CTSA) Program National Center for Data to Health (CD2H). The persona profiles were designed and researched to demonstrate the key responsibilities, motivators, goals, software use, pain points, and professional development needs of those working across the spectrum of translation, from basic science to clinical research to public health. The project’s goal was to provide reliable documents that could be used to inform CTSA software development projects, educational resources, and communication initiatives. This paper presents the initiative to create personas for the translational workforce, including the methodology, engagement strategy, and lessons learned. Challenges faced and successes achieved by the project may serve as a roadmap for others searching for best practices in the creation of Persona profiles.
Introduction: Simulation has assumed an integral role in the Canadian healthcare system with applications in quality improvement, systems development, and medical education. High quality simulation-based research (SBR) is required to ensure the effective and efficient use of this tool. This study sought to establish national SBR priorities and describe the barriers and facilitators of SBR in Emergency Medicine (EM) in Canada. Methods: Simulation leads (SLs) from all fourteen Canadian Departments or Divisions of EM associated with an adult FRCP-EM training program were invited to participate in three surveys and a final consensus meeting. The first survey documented active EM SBR projects. Rounds two and three established and ranked priorities for SBR and identified the perceived barriers and facilitators to SBR at each site. Surveys were completed by SLs at each participating institution, and priority research themes were reviewed by senior faculty for broad input and review. Results: Twenty SLs representing all 14 invited institutions participated in all three rounds of the study. 60 active SBR projects were identified, an average of 4.3 per institution (range 0-17). 49 priorities for SBR in Canada were defined and summarized into seven priority research themes. An additional theme was identified by the senior reviewing faculty. 41 barriers and 34 facilitators of SBR were identified and grouped by theme. Fourteen SLs representing 12 institutions attended the consensus meeting and vetted the final list of eight priority research themes for SBR in Canada: simulation in CBME, simulation for interdisciplinary and inter-professional learning, simulation for summative assessment, simulation for continuing professional development, national curricular development, best practices in simulation-based education, simulation-based education outcomes, and simulation as an investigative methodology. Conclusion: Conclusion: This study has summarized the current SBR activity in EM in Canada, as well as its perceived barriers and facilitators. We also provide a consensus on priority research themes in SBR in EM from the perspective of Canadian simulation leaders. This group of SLs has formed a national simulation-based research group which aims to address these identified priorities with multicenter collaborative studies.
Organic pig husbandry systems in Europe are diverse – ranging from indoor systems with concrete outside run (IN) to outdoor systems all year round (OUT) and combinations of both on one farm (POUT). As this diversity has rarely been taken into account in research projects on organic pig production, the aim of this study was to assess and compare pig health, welfare and productivity in these three systems. Animal health and welfare were assessed using direct observation and records of 22 animal-based measures, comprising 17 health-, 3 productivity- and 2 behavioural measures. These were collected in pregnant sows, weaners and fattening pigs during direct observations and from records within a cross-sectional study on 74 farms (IN: n = 34, POUT: n = 28, OUT: n = 12) in eight countries. Overall, prevalence of several animal health and welfare issues was low (e.g. median 0% for pigs needing hospitalisation, shoulder lesions, ectoparasites; <5% for runts, tail lesions, conjunctivitis). Exceptions in particular systems were respiratory problems in weaners and fatteners (IN: 60.0%, 66.7%; POUT: 66.7%, 60.0%), weaning diarrhoea (IN: 25.0%), and short tails in fatteners (IN: 6.5%, POUT: 2.3%). Total suckling piglet losses (recorded over a period of 12 months per farm) were high in all three systems (IN: 21.3%; POUT: 21.6; OUT: 19.2%). OUT had lower prevalences of respiratory problems, diarrhoea and lameness of sows. POUT farms in most cases kept sows outdoors and weaners and fatteners similar to IN farms, which was reflected in the results regarding several health and welfare parameters. It can be concluded, that European organic pigs kept in all three types of husbandry system showed a low prevalence of health and welfare problems as assessed by our methodology, but respiratory health and diarrhoea should be improved in weaners and fatteners kept indoors and total piglet mortality in all systems. The results provide benchmarks for organic pig producers and organisations which can be used in strategies to promote health and welfare improvement. Furthermore, in future research, the identified health and welfare issues (e.g. suckling piglet mortality, weaning diarrhoea) should be addressed, specifically considering effects of husbandry systems.
The association between lifestyle and survival after colorectal cancer has received limited attention. The female sex hormone, oestrogen, has been associated with lower colorectal cancer risk and mortality after colorectal cancer. Phyto-oestrogens are plant compounds with structure similar to oestrogen, and the main sources in Western populations are plant lignans. We investigated the association between the main lignan metabolite, enterolactone and survival after colorectal cancer among participants in the Danish Diet, Cancer and Health cohort. Prediagnosis plasma samples and lifestyle data, and clinical data from time of diagnosis from 416 women and 537 men diagnosed with colorectal cancer were used. Enterolactone was measured in plasma using a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. Participants were followed from date of diagnosis until death or end of follow-up. During this time, 210 women and 325 men died (170 women and 215 men died due to colorectal cancer). The Cox proportional hazards model was used to estimate hazard ratios (HR) and 95 % CI. Enterolactone concentrations were associated with lower colorectal cancer-specific mortality among women (HRper doubling: 0·88, 95 % CI 0·80, 0·97, P=0·0123). For men, on the contrary, enterolactone concentrations were associated with higher colorectal cancer-specific mortality (HRper doubling: 1·10, 95 % CI 1·01, 1·21, P=0·0379). The use of antibiotics affects enterolactone production, and the associations between higher enterolactone and lower colorectal cancer-specific mortality were more pronounced among women who did not use antibiotics (analysis on a subset). Our results suggest that enterolactone is associated with lower risk of mortality among women, but the opposite association was found among men.
To identify predominant dietary patterns in four African populations and examine their association with obesity.
We used data from the Africa/Harvard School of Public Health Partnership for Cohort Research and Training (PaCT) pilot study established to investigate the feasibility of a multi-country longitudinal study of non-communicable chronic disease in sub-Saharan Africa. We applied principal component analysis to dietary intake data collected from an FFQ developed for PaCT to ascertain dietary patterns in Tanzania, South Africa, and peri-urban and rural Uganda. The sample consisted of 444 women and 294 men.
We identified two dietary patterns: the Mixed Diet pattern characterized by high intakes of unprocessed foods such as vegetables and fresh fish, but also cold cuts and refined grains; and the Processed Diet pattern characterized by high intakes of salad dressing, cold cuts and sweets. Women in the highest tertile of the Processed Diet pattern score were 3·00 times more likely to be overweight (95 % CI 1·66, 5·45; prevalence=74 %) and 4·24 times more likely to be obese (95 % CI 2·23, 8·05; prevalence=44 %) than women in this pattern’s lowest tertile (both P<0·0001; prevalence=47 and 14 %, respectively). We found similarly strong associations in men. There was no association between the Mixed Diet pattern and overweight or obesity.
We identified two major dietary patterns in several African populations, a Mixed Diet pattern and a Processed Diet pattern. The Processed Diet pattern was associated with obesity.
The main resource for a country’s endogenous growth is its human and cultural capital. Universities play a very important, but not the only, role in maintaining and building this resource. Universities are institutions situated amongst strong and changing forces. They are caught between government, market and academia. In many institutions, this has led to a strengthening of the executive leadership at the expense of the influence of collegial bodies, and external (to the institution) members have been introduced into the governing bodies. This development has resulted in diminished state control, and more flexible and autonomous systems, but also to expanded reporting and accounting, which often in reality limit freedom and are perceived as control. Will academic creativity thrive within this reality? How would research universities evolve? This article claims that today’s university development starts out from Wilhelm von Humboldt’s universe but will play out in that of his brother Alexander’s.
Identifying clinical features that predict conversion to bipolar disorder (BD) in those at high familial risk (HR) would assist in identifying a more focused population for early intervention.
In total 287 participants aged 12–30 (163 HR with a first-degree relative with BD and 124 controls (CONs)) were followed annually for a median of 5 years. We used the baseline presence of DSM-IV depressive, anxiety, behavioural and substance use disorders, as well as a constellation of specific depressive symptoms (as identified by the Probabilistic Approach to Bipolar Depression) to predict the subsequent development of hypo/manic episodes.
At baseline, HR participants were significantly more likely to report ⩾4 Probabilistic features (40.4%) when depressed than CONs (6.7%; p < .05). Nineteen HR subjects later developed either threshold (n = 8; 4.9%) or subthreshold (n = 11; 6.7%) hypo/mania. The presence of ⩾4 Probabilistic features was associated with a seven-fold increase in the risk of ‘conversion’ to threshold BD (hazard ratio = 6.9, p < .05) above and beyond the fourteen-fold increase in risk related to major depressive episodes (MDEs) per se (hazard ratio = 13.9, p < .05). Individual depressive features predicting conversion were psychomotor retardation and ⩾5 MDEs. Behavioural disorders only predicted conversion to subthreshold BD (hazard ratio = 5.23, p < .01), while anxiety and substance disorders did not predict either threshold or subthreshold hypo/mania.
This study suggests that specific depressive characteristics substantially increase the risk of young people at familial risk of BD going on to develop future hypo/manic episodes and may identify a more targeted HR population for the development of early intervention programs.
The surveillance of Clostridium difficile (CD) in Denmark consists of laboratory based data from Departments of Clinical Microbiology (DCMs) sent to the National Registry of Enteric Pathogens (NREP). We validated a new surveillance system for CD based on the Danish Microbiology Database (MiBa). MiBa automatically collects microbiological test results from all Danish DCMs. We built an algorithm to identify positive test results for CD recorded in MiBa. A CD case was defined as a person with a positive culture for CD or PCR detection of toxin A and/or B and/or binary toxin. We compared CD cases identified through the MiBa-based surveillance with those reported to NREP and locally in five DCMs representing different Danish regions. During 2010–2014, NREP reported 13 896 CD cases, and the MiBa-based surveillance 21 252 CD cases. There was a 99·9% concordance between the local datasets and the MiBa-based surveillance. Surveillance based on MiBa was superior to the current surveillance system, and the findings show that the number of CD cases in Denmark hitherto has been under-reported. There were only minor differences between local data and the MiBa-based surveillance, showing the completeness and validity of CD data in MiBa. This nationwide electronic system can greatly strengthen surveillance and research in various applications.
Salmonella is a leading cause of bacterial foodborne illness. We report the collaborative investigative efforts of US and Canadian public health officials during the 2013–2014 international outbreak of multiple Salmonella serotype infections linked to sprouted chia seed powder. The investigation included open-ended interviews of ill persons, traceback, product testing, facility inspections, and trace forward. Ninety-four persons infected with outbreak strains from 16 states and four provinces were identified; 21% were hospitalized and none died. Fifty-four (96%) of 56 persons who consumed chia seed powder, reported 13 different brands that traced back to a single Canadian firm, distributed by four US and eight Canadian companies. Laboratory testing yielded outbreak strains from leftover and intact product. Contaminated product was recalled. Although chia seed powder is a novel outbreak vehicle, sprouted seeds are recognized as an important cause of foodborne illness; firms should follow available guidance to reduce the risk of bacterial contamination during sprouting.
Angiopoietin-like protein 4 (ANGPTL4) is a lipoprotein lipase inhibitor that is involved in lipid metabolism and angiogenesis. Animal studies have suggested that the ANGPTL4 protein is modulated by the gut microbiota, possibly through increased concentrations of SCFA, such as C4, found in whole-fat milk or as a result of fermentation of inulin. This study investigated whether a standardised diet either high in fat content or supplemented with inulin powder would increase plasma ANGPTL4 in overweight men and whether this increase was mediated through a compositional change of the gut microbiota. The study had a crossover design with three arms, where participants were given a standardised isoenergetic diet supplemented with inulin powder, whole-fat milk or water (control). Plasma and urine samples were collected before and after each intervention period. Faecal samples and adipose tissue biopsies were collected after each intervention period. The study included twenty-one participants of whom eighteen completed the study. The dietary interventions did not change ANGPTL4 plasma concentration, nor was plasma ANGPTL4 associated with plasma lipids, TAG or NEFA concentration. The relative abundance of bifidobacteria following the inulin diet was higher, compared with the control diet. However, the changes in microbiota were not associated with plasma ANGPTL4 and the overall composition of the microbiota did not change between the dietary periods. Although weight was maintained throughout the dietary periods, weight was negatively associated with plasma ANGPTL4 concentration. In the adipose tissue, ANGPTL4 expression was correlated with leptin expression, but not with hypoxia-inducible factor 1α (HIF-1α) expression.
We document the use of organic raw material in late Pleistocene eastern Beringia through the study of the site of Swan Point CZ4b, in central Alaska. CZ4b is attributed to the Dyuktai culture and dates to about 14,000 cal B.P. We interpret the occupation as a specialized workshop dedicated to the production and maintenance of organic-based tools following three lines of evidence: (1) limited on-site consumption of megafauna, (2) diversity of organic raw materials and techniques used in processing them, and (3) spatial demarcation of specialized activity areas. Specialized workshops are located in the vicinity of naturally occurring accumulations of mammoth bones in both western and eastern Beringia and suggest similarities in animal resource use across Beringia for the Dyuktai culture. Organic technology was a major portion of Dyuktai technology in eastern Beringia, and its lack of visibility in archaeological assemblages is probably due to taphonomic reasons. Changes in the availability of organic raw material throughout the Late Pleistocene offer some implications for the evolution of lithic technology and material culture.
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.
Efforts to develop the next generation of aircraft with ever-increasing levels of performance – higher, farther, faster, cheaper – face great technical challenges. One of these technical challenges is to reduce structural weight of the aircraft. Another is to look to aircraft configurations that have been unrealizable to date. Both of these paths can lead to a rigid flex coupling phenomenon that can result in anything from poor flying qualities to the loss of an aircraft due to flutter. This has led to a need to develop an integrated flight and aeroelastic control capability where structural dynamics are included in the synthesis of flight control laws. Studies have indicated that the application of an integrated flight and aeroelastic control approach to a SensorCraft high-altitude long-endurance vehicle would provide substantial performance improvement(1,2). Better flying qualities and an expanded flight envelope through multi-flutter mode control are two areas of improvement afforded by integrated flight and aeroelastic control. By itself, multi-flutter mode control transforms the flutter barrier from a point of catastrophic structural failure to a benign region of flight. This paper discusses the history and issues associated with the development of such an integrated flight and aeroelastic control system for the X-56A aircraft.
The Cosmology Distinction Course is a new one-year course to be introduced for Year 12 candidates in the 1994 Higher School Certificate examinations in NSW. It is one of three challenging courses of study that will enrich the HSC for talented students who accelerate and complete part of the HSC one year early. The courses will be taught through distance learning and will include residential seminars. They will be implemented on behalf of the Board of Studies by Charles Sturt University and the University of New England.
The Cosmology Course is organised into nine modules of course work covering historical and social aspects of cosmology, observational techniques, key observations and the various models developed—Newtonian, de Sitter, Friedmann, Lemaitre, steady-state, quasi-steady-state and big bang. Assessment will be through assignments, exams and a major project.
As the first Distinction Course in a scientific area, the Cosmology Course represents an exciting and important educational initiative that needs the cooperation of NSW astronomers and, in return, promises to benefit the astronomical and general scientific community in Australia.
Chemical insecticides have been an important tool in the management of forest insect pests in Canadian forests. Aerial application of insecticides began in the 1920s and expanded greatly after World War II with the widespread adoption of DDT primarily for the suppression of spruce budworm, Choristoneura fumiferana Clemens (Lepidoptera: Tortricidae), and other defoliating insects. Significant progress was made in the development of new chemical insecticides and formulations including fenitrothion and tebufenozide, as well as technology for the application of insecticides against various insect pests. However, widespread opposition to the use of chemical insecticides in forest management has led to significant reductions in the number of insecticides registered for use in Canadian forests. Developments in the past 20 years have focussed on new insecticides, formulations, and technologies that seek to limit the impacts on non-target organisms and subsequent ecosystem effects. These developments have resulted in significant improvements in the management of traditional management targets, such as the spruce budworm (Choristoneura fumiferana (Clemens); Lepidoptera: Tortricidae) but also the management of invasive species, especially wood-boring beetles (Coleoptera: Buprestidae, Cerambycidae).