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Refugees and asylum-seekers are typically exposed to multiple potentially traumatic events (PTEs) in the context of war, persecution and displacement, which confer elevated risk for psychopathology. There are significant limitations, however, in extant approaches to measuring these experiences in refugees. The current study aimed to identify profiles of PTE exposure, and the associations between these profiles and key demographics, contextual factors (including ongoing stressors, method of travel to Australia and separation from family), mental health and social outcomes, in a large sample of refugees resettled in Australia.
Participants were 1085 from Arabic, Farsi, Tamil and English-speaking refugee backgrounds who completed an online or pen-and-paper survey in their own language. Constructs measured included PTE exposure, demographics, pre-displacement factors, ongoing stressors, post-traumatic stress disorder symptoms, depression symptoms, anger reactions, plans of suicide and social engagement.
Latent class analysis identified four profiles of PTE exposure, including the torture and pervasive trauma class, the violence exposure class, the deprivation exposure class and the low exposure class. Compared to the low exposure class, participants in the trauma-exposed classes were more likely to be male, highly educated, from Farsi and Tamil-speaking backgrounds, have travelled to Australia by boat, experience more ongoing stressors and report both greater psychological symptoms and social engagement.
This study found evidence for four distinct profiles of PTE exposure in a large sample of resettled refugees, and that these were associated with different demographic, psychological and social characteristics. These findings suggest that person-centred approaches represent an important potential avenue for investigation of PTE exposure in refugees, particularly with respect to identifying subgroups of refugees who may benefit from different types or levels of intervention according to their pre-migration PTE experiences.
Recent work studying triadic closure in undirected graphs has drawn attention to the distinction between measures that focus on the “center” node of a wedge (i.e., length-2 path) versus measures that focus on the “initiator,” a distinction with considerable consequences. Existing measures in directed graphs, meanwhile, have all been center-focused. In this work, we propose a family of eight directed closure coefficients that measure the frequency of triadic closure in directed graphs from the perspective of the node initiating closure. The eight coefficients correspond to different labeled wedges, where the initiator and center nodes are labeled, and we observe dramatic empirical variation in these coefficients on real-world networks, even in cases when the induced directed triangles are isomorphic. To understand this phenomenon, we examine the theoretical behavior of our closure coefficients under a directed configuration model. Our analysis illustrates an underlying connection between the closure coefficients and moments of the joint in- and out-degree distributions of the network, offering an explanation of the observed asymmetries. We also use our directed closure coefficients as predictors in two machine learning tasks. We find interpretable models with AUC scores above 0.92 in class-balanced binary prediction, substantially outperforming models that use traditional center-focused measures.
Cardiac catheterisation is commonly used for diagnosis and therapeutic interventions in paediatric cardiology. The inherent risk of the procedure can result in unanticipated admissions to critical care. Our goals were to provide a qualitative description of characteristics and evaluation of children admitted unexpectedly to the cardiac critical care unit (CCCU).
A retrospective single centre review of cardiac catheterisation procedures was done between 1 January, 2003 and 30 April, 2013.
Of 9336 cardiac catheterisations performed, 146 (1.6%) were admitted from the catheterisation laboratory to the CCCU and met inclusion criteria. Of these 146 patients, 117 (1.3%) met criteria for unexpected admission and 29 (0.3%) were planned admissions. The majority admitted unexpectedly were below 1 year of age without co-morbidity aside from heart disease. Patients with planned admissions were significantly more likely to have single ventricle physiology, undergoing angiography or transferred for observation. Most unplanned admissions were triggered by interventional catheterisations or procedure-related complications. Patients received mechanical ventilation as the main CCCU management. Eighteen patients needed either cardiopulmonary resuscitation and/or extracorporeal membrane oxygenation during their catheterisation. About 106/117 (90.6%) patients survived to hospital discharge with no deaths in the planned admission group.
Admission to CCCU following cardiac catheterisation was uncommon and tended to occur in younger children undergoing interventional procedures. Outcomes did not differ between patients experiencing planned and unplanned CCCU admission. Ongoing development of risk stratification tools may help to decrease unplanned CCCU admissions. Further studies are needed to determine whether unplanned admission following paediatric cardiac catheterisation should be utilised as a quality indicator.
Sinonasal undifferentiated carcinoma is a rare aggressive tumour arising from the Schneiderian epithelium lining the sinonasal tract. Although considered the cornerstone of therapy, surgical resection can only be performed in a limited number of patients. This report describes the experience of treating sinonasal undifferentiated carcinoma with a multimodality approach.
The treatment charts of sinonasal undifferentiated carcinoma patients treated at a tertiary care centre from 2004 to 2012 were retrospectively reviewed.
A total of 16 sinonasal undifferentiated carcinoma patients with a median age at diagnosis of 47.5 years (range 8–65 years) were included: 19 per cent had neck nodal metastasis at presentation. Four patients (25 per cent) underwent surgery: of these, two had post-operative radiotherapy, one had pre-operative radiotherapy and one had adjuvant chemotherapy alone. Six patients (38 per cent) received definitive radiotherapy: five had received neoadjuvant chemotherapy to reduce tumour size and help in radiotherapy planning, while four (25 per cent) received palliative radiotherapy. The median follow up was 10.4 months (range 1–42.5 months). The estimated median progression-free survival time was 29.3 months. One- and three-year progression-free survival rates were 77 per cent and 41 per cent, respectively.
Surgery is the best treatment option for sinonasal undifferentiated carcinoma, although most patients require post-operative radiotherapy for advanced disease and close tumour margins. Definitive radiotherapy with or without chemotherapy may be suitable for patients with inoperable locally advanced disease. Elective nodal irradiation to address the high nodal involvement rates should be considered to improve the survival rate.
The objective of this study was to report procedural characteristics and adverse events on the data collected in the IMproving Paediatric and Adult Congenital Treatment registry.
The IMproving Paediatric and Adult Congenital Treatment– registry is a catheterisation registry focussed on paediatric and adult patients with congenital heart disease who are undergoing diagnostic catheterisations and catheter-based interventions. This study reports procedural characteristics and adverse events of patients who have undergone selected catheterisation procedures from January, 2011 to June, 2013.
Demographic, clinical, procedural, and institutional data elements were collected at participating centres and entered via either a web-based platform or software provided by the American College of Cardiology-certified vendors, and were collected in a secure, centralised database. For the purpose of this study, procedures that were not classified as one of the ‘core’ IMproving Paediatric and Adult Congenital Treatment procedures originally chosen for additional data collection were identified and selected for further data analysis.
During the time frame of data collection, a total of 8021 cases were classified as other procedures and/or multiple procedures. The most commonly performed case types – isolated or in combination with other procedures – were right ventricular biopsy in 3433 (42.8%), conduit/MPA interventions in 979 (12.3%), and systemic pulmonary artery collateral occlusion in 601 (7.5%). For the whole cohort, adverse events of any severity occurred in 957 (12.0%) cases, whereas major adverse events occurred in 113 (1.4%) cases; six patients (0.1%) died in the catheterisation laboratory.
The IMproving Paediatric and Adult Congenital Treatment registry has provided important data on the frequency and spectrum of cardiac catheterisation procedures performed in the present era. For many procedures, more data and work are needed to identify more subtle differences between case categories, especially as it relates to the incidence of major adverse events, and to further develop a risk-adjustment methodology to allow equitable comparisons among institutions.
To report procedural characteristics and adverse events on data collected in the registry.
The IMPACT – IMproving Paediatric and Adult Congenital Treatment – Registry is a catheterisation registry of paediatric and adult patients with CHD undergoing diagnostic and interventional cardiac catheterisation. We are reporting the procedural characteristics and adverse events of patients undergoing diagnostic and interventional catheterisation procedures from January, 2011 to March, 2013.
Demographic, clinical, procedural, and institutional data elements were collected at the participating centres and entered via either a web-based platform or software provided by American College of Cardiology-certified vendors, and were collected in a secure, centralised database. Centre participation was voluntary.
During the time frame of data collection, 19,797 procedures were entered into the IMPACT Registry. Procedures were classified as diagnostic only (35.4%); one of six specific interventions (23.8%); other or multiple interventions (40.7%); and were further broken down into four age groups. Anaesthesia was used in 84.1% of diagnostic procedures and 87.8% of interventional ones. Adverse events occurred in 10.0% of diagnostic and 11.1% of interventional procedures.
The IMPACT Registry is gathering data to set national benchmarks for diagnostic and certain specific interventional procedures. We are seeing little differences in procedural characteristics or adverse events in diagnostic procedures compared with interventional procedures overall, but there is significant variation in adverse events amongst age categories. Risk stratification and patient acuity scores will be required for further analysis of these differences.
To determine the incidence of high jugular bulb in a group of patients with definite Ménière's disease, and to investigate whether the position or size of the jugular bulb is significantly different in the affected ear than in the unaffected ear.
Retrospective review of patient charts, audiograms, and computed tomography scans to determine the position and size of the jugular bulb in the affected and contralateral ears, as well as other abnormalities.
High jugular bulb was found in 57.1 per cent of affected ears. Encroachment of the cochlear and vestibular aqueducts was apparent in 39.3 per cent and 35.7 per cent, respectively, of affected ears. Diverticulum and dehiscence were observed in 28.6 per cent of affected ears. High jugular bulb was significantly associated with encroachment of the cochlear aqueduct (p = 0.003).
The mediolateral and anteroposterior position of the jugular bulb determines encroachment of the surrounding structures. An abnormal position is postulated to contribute to the development of Ménière's disease.
Behavioral inhibition, a temperament identifiable in infancy, is associated with heightened withdrawal from social encounters. Prior studies raise particular interest in the striatum, which responds uniquely to monetary gains in behaviorally inhibited children followed into adolescence. Although behavioral manifestations of inhibition are expressed primarily in the social domain, it remains unclear whether observed striatal alterations to monetary incentives also extend to social contexts. In the current study, imaging data were acquired from 39 participants (17 males, 22 females; ages 16–18 years) characterized since infancy on measures of behavioral inhibition. A social evaluation task was used to assess neural response to anticipation and receipt of positive and negative feedback from novel peers, classified by participants as being of high or low interest. As with monetary rewards, striatal response patterns differed during both anticipation and receipt of social reward between behaviorally inhibited and noninhibited adolescents. The current results, when combined with prior findings, suggest that early-life temperament predicts altered striatal response in both social and nonsocial contexts and provide support for continuity between temperament measured in early childhood and neural response to social signals measured in late adolescence and early adulthood.
The IceCube Neutrino Observatory was constructed at the South Pole during the 2004/05 to 2010/11 austral summer seasons. IceCube transforms 1 km3 of Antarctic ice into an astrophysical particle detector composed of 86 cables (strings) of optical sensors buried deep beneath the surface. Each string required drilling a borehole ∼60 cm in diameter to a depth of 2500 m. The 5 MW Enhanced Hot Water Drill was designed and built specifically for this task, capable of producing the required boreholes at a rate of one hole per 48 hours. Hot-water drilling on this scale presented unique challenges and was rich in lessons learned, yielding a collection of notable developments and takeaways (e.g. fuel-saving measures, thermal modeling, firn drilling and closed-loop computer control). Descriptions of system functionality and of lessons learned from IceCube drilling are presented.
IceCube, a cubic-kilometer neutrino detector, was built at the South Pole using a hot-water drill system. Deep holes were drilled into the Antarctic ice sheet and filled with highly sensitive optical instrumentation. For the hot-water drilling, a computer model was developed to predict the hole sizes and hole lifetimes during construction. The goal was to predict ultimate size and freezeback rates based on water flow rate and temperature, drill speed, ice temperature and ream parameters (for a secondary operation where hot water continues to flow as the drill is withdrawn). This model proved to be very successful. It increased confidence that the holes would remain open long enough after drilling to allow the deployment of the necessary instrumentation. It also allowed for a decrease, over the course of the project, in the amount of overdrilling that was used as a margin against a too-rapid freeze-in. This resulted in significant fuel savings.
Biological reference points (BRPs) in fisheries policy are typically sensitive to stock assessment model assumptions, thus increasing uncertainty in harvest decision-making and potentially blocking adoption of precautionary harvest policies. A collaborative management strategy evaluation approach and closed-loop simulation modelling was used to evaluate expected fishery economic and conservation performance of the sablefish (Anoplopoma fimbria) fishery in British Columbia (Canada), in the presence of uncertainty about BRPs. Comparison of models derived using two precautionary harvest control rules, which each complied with biological conservation objectives and short-term economic objectives given by industry, suggested that both rules were likely to avert biomass decline below limit BRPs, even when stock biomass and production were persistently overestimated by stock assessment models. The slightly less conservative, industry-preferred harvest control rule also avoided short-term economic losses of c. CAN$ 2.7–10 million annually, or 10–50% of current landed value. Distinguishing between the role of BRPs in setting fishery conservation objectives and operational control points that define harvest control rules improved the flexibility of the sablefish management system, and has led to adoption of precautionary management procedures.
Energy is essential for human development and energy systems are a crucial entry point for addressing the most pressing global challenges of the 21st century, including sustainable economic and social development, poverty eradication, adequate food production and food security, health for all, climate protection, conservation of ecosystems, peace and security. Yet, more than a decade into the 21st century, current energy systems do not meet these challenges.
A major transformation is therefore required to address these challenges and to avoid potentially catastrophic future consequences for human and planetary systems. The Global Energy Assessment (GEA) demonstrates that energy system change is the key for addressing and resolving these challenges. The GEA identifies strategies that could help resolve the multiple challenges simultaneously and bring multiple benefits. Their successful implementation requires determined, sustained and immediate action.
Transformative change in the energy system may not be internally generated; due to institutional inertia, incumbency and lack of capacity and agility of existing organizations to respond effectively to changing conditions. In such situations clear and consistent external policy signals may be required to initiate and sustain the transformative change needed to meet the sustainability challenges of the 21st century.
The industrial revolution catapulted humanity onto an explosive development path, whereby, reliance on muscle power and traditional biomass was replaced mostly by fossil fuels. In 2005, some 78% of global energy was based on fossil energy sources that provided abundant and ever cheaper energy services to more than half the people in the world.
Energy is essential for human development and energy systems are a crucial entry point for addressing the most pressing global challenges of the 21st century, including sustainable economic, and social development, poverty eradication, adequate food production and food security, health for all, climate protection, conservation of ecosystems, peace, and security. Yet, more than a decade into the 21st century, current energy systems do not meet these challenges.
In this context, two considerations are important. The first is the capacity and agility of the players within the energy system to seize opportunities in response to these challenges. The second is the response capacity of the energy system itself, as the investments are long-term and tend to follow standard financial patterns, mainly avoiding risks and price instabilities. This traditional approach does not embrace the transformation needed to respond properly to the economic, environmental, and social sustainability challenges of the 21st century.
A major transformation is required to address these challenges and to avoid potentially catastrophic consequences for human and planetary systems. The GEA identifies strategies that could help resolve the multiple challenges simultaneously and bring multiple benefits. Their successful implementation requires determined, sustained, and immediate action.
The industrial revolution catapulted humanity onto an explosive development path, whereby reliance on muscle power and traditional biomass was replaced mostly by fossil fuels. In 2005, approximately 78% of global energy was based on fossil energy sources that provided abundant and ever cheaper energy services to more than half the world's population.
A variety of means, including forelimb proportions and shell bone histology have been used to infer the paleoecology of extinct turtles. However, the height-to-width ratio of the shell (as a one-parameter shell model) has been dismissed because of its unreliability, and more complex aspects of shell geometry have generally been overlooked. Here we use a more reliable, three-parameter geometric model of the shell outline in anterior view as a means to assess turtle paleoecology. The accuracy of predictions of extant turtle ecology based on our three-parameter shell model is comparable to that derived from forelimb proportions when distinguishing between three ecological classes (terrestrial, semiaquatic, and aquatic). Higher accuracy is obtained when distinguishing between two classes (terrestrial and non-terrestrial), because the contours of aquatic and semiaquatic turtles are often very similar. Our model classifies Proterochersis robusta, a stem turtle from the Late Triassic of Germany, as non-terrestrial, and likely semiaquatic. Our method, combined with inferences based on limb proportions, indicates a diverse range of ecotypes represented by Late Triassic stem turtles. This implies that the ecological diversification of stem-group turtles may have been rapid, or that a substantial period of currently cryptic diversification preceded the first fossil appearance of the turtle stem lineage during the Late Triassic.
The development of synthetic materials with inherent bone properties would allow the safe restoration of bone function and reduce current risks associated with the use of grafts. This study investigated the development of bacterial cellulose–hydroxyapatite composite (CdHA-BC) as a potential bone substitute material. Composites of bacterial cellulose (BC) and oxidized, degradable, cellulose (OBC) were mineralized by sequential incubation in calcium chloride and aqueous sodium phosphate to form a calcium deficient hydroxyapatite (CdHA). The CdHA produced in BC and OBC is similar in morphology and chemistry to the hydroxyapatite found in natural bone. The formation of CdHA is supported by XRD, and EDS results. The CdHA-BC and CdHA-OBC composites degrade in a simulated aqueous physiological environment.