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Defence Science and Technology Group (DSTG) is currently preparing for the launch of the Buccaneer Main Mission (BMM) satellite, the successor to the Buccaneer Risk Mitigation Mission (BRMM). BMM hosts a high-frequency (HF) antenna and receiver to contribute to the calibration of the Jindalee Operational Radar Network (JORN). Verification of the successful deployment and stability of the large HF antenna is critical to the success of the mission. A bespoke deployable optics payload has been developed by DSTG to fulfil the dual purpose of direct verification of the deployed state of the HF antenna and capturing images of the Earth through a rotatable, dual-surfaced mirror and a variable-focus liquid lens. The payload advances research at DSTG in several fields of space engineering, including deployable mechanisms, precision actuation devices, radiation-tolerant electronics, advanced metal polishing and optical metrology. This paper discusses the payload design, material selection, trade-offs considered for the deployable optics payload and preliminary test results.
Research on proactive and reactive aggression has identified covariates unique to each function of aggression, but hypothesized correlates have often not been tested with consideration of developmental changes in or the overlap between the types of aggression. The present study examines the unique developmental trajectories of proactive and reactive aggression over adolescence and young adulthood and tests these trajectories’ associations with key covariates: callous–unemotional (CU) traits, impulsivity, and internalizing emotions. In a sample of 1,211 justice-involved males (ages 15–22), quadratic growth models (i.e., intercepts, linear slopes, and quadratic slopes) of each type of aggression were regressed onto quadratic growth models of the covariates while controlling for the other type of aggression. After accounting for the level of reactive aggression, the level of proactive aggression was predicted by the level of CU traits. However, change in proactive aggression over time was not related to the change in any covariates. After accounting for proactive aggression, reactive aggression was predicted by impulsivity, both at the initial level and in change over time. Results support that proactive and reactive aggression are unique constructs with separate developmental trajectories and distinct covariates.
We examined the effects of two different methods of castration on the behaviour of lambs of two age groups. Rubber ring castration and combined rubber ring and Burdizzo clamp castration were compared in groups of one-week-old lambs and four-to six-week-old lambs. Behaviour was assessed by examining time-lapse video recordings made continuously over four days. Postures and behavioural states were instantaneously sampled and the mean daily frequencies of these behaviours calculated. Behaviours were assigned to different groups: standing still, moving, eating, lying, playing and abnormal postures. The times spent performing each group of behaviours on the days following castration (days 2, 3 and 4) were compared to those on the day preceding castration (day 1). Castration resulted in significant reductions in the times spent performing play behaviour in one-week-old lambs and lying behaviour in four-to six-week-old lambs. There was also a significant increase in abnormal postures following castration in four- to six-week-old lambs. There were no detectable differences between castration methods. The results show that lambs exhibit changes in behaviour over the three-day observation period that are suggestive of the presence of prolonged acute pain. These results have important implications regarding the sheep welfare recommendations of the Farm Animal Welfare Council, which propose to extend the maximum legal age for rubber ring castration from one week to six weeks of age.
OBJECTIVES/GOALS: This presentation outlines a novel approach to evaluating multiple risk factors for the development of dose-limiting toxicities in adolescents and young adults with cancer. This is the first to evaluate biobehavioral predictors originally identified in animal models in clinical human studies. METHODS/STUDY POPULATION: Adolescents and young adults (AYAs) have seen the slowest improvements in cancer survival and have some of the highest rates of dose-limiting mucositis (mouth sores). AYAs receiving chemotherapy with a significant chance of dose-limiting mucositis were recruited for a prospective study. Baseline perceived psychologic stress levels and inflammatory markers were collected at the time of chemotherapy administration and participants completed a daily assessment of mucositis for 14 days following chemotherapy. Logistic regression will be used to evaluate stress and inflammation as predictors of mucositis and Sobels testing will evaluate the role of inflammation as mediators in this relationship. RESULTS/ANTICIPATED RESULTS: We anticipate that, as seen in animal models, stress and inflammation will predict mucositis development. First, we hypothesize that stress levels and inflammatory markers will have a direct correlation and that the level of inflammation at the time of chemotherapy administration will predict mucositis incidence and severity. Through mediation testing, we hypothesize that inflammatory markers will explain a significant amount of the variance in mucositis also explained by stress, identifying inflammation as a mediator in this relationship. In all, we expect that stress and inflammation both predict mucositis development and will be identified as important modifiable factors that can be altered to reduce the risk of toxicity development during cancer therapy. DISCUSSION/SIGNIFICANCE: This work intends to evaluate predictors of chemotherapy-related toxicity development in AYAs with cancer and identify areas of intervention that will reduce toxicity profiles and close the gap in cancer survival for AYAs. Findings are applicable to biomedical, nursing, and psychosocial professionals and will inform future, large clinical studies
To explore differences in proportion of food budget and total food expenditure by dwelling type.
Design:
A cross-sectional study using data from the Australian Bureau of Statistics 2015–2016 Household Expenditure Survey. Food expenditure was examined on multiple categories: fresh fruits, fresh vegetables, pre-prepared meals, meals in restaurants, hotels and clubs, and fast food and takeaway meals, using two-part models and zero-one inflated beta regression models. Dwelling types were categorised as separate house, semi-detached house, low-rise apartment and high-rise apartment.
Setting:
Australia, 2015–2016.
Participants:
Seven thousand three hundred and fifty-eight households from greater capital city areas.
Results:
Households living in high-rise apartments were estimated to allocate a greater proportion of their food budget to meals in restaurants, hotels and clubs, and to spend more (actual dollars) on that category, compared with other dwelling types. No substantial differences were estimated in the proportion of food budget allocated to the other food categories across dwelling types.
Conclusions:
The dwelling type households live in may play a role in their food budget. Households living in a high-rise apartment may potentially spend more on meals in restaurants, hotels and clubs than those living in other dwelling types. Given the growth in urban population and the changes in living arrangements, findings point to the critical need for a better understanding of the influence of dwelling types on food expenditure and call for research investigating the relationship between the two.
The otoliths (ear stones) of fishes are commonly used to describe the age and growth of marine and freshwater fishes. These non-skeletal structures are fortuitous in their utility by being composed of mostly inorganic carbonate that is inert through the life of the fish. This conserved record functions like an environmental chronometer and bomb-produced radiocarbon (14C)—a 14C signal created by atmospheric testing of thermonuclear devices—can be used as a time-specific marker in validating fish age. However, complications from the hydrogeology of nearshore marine environments can complicate 14C levels, as was the case with gray snapper (Lutjanus griseus) along the Gulf of Mexico coast of Florida. Radiocarbon of these nearshore waters is influenced by freshwater input from the karst topography of the Upper Floridan Aquifer—estuarine waters that are 14C-depleted from surface and groundwater inputs. Some gray snapper likely recruited to this kind of environment where 14C levels were depleted in the earliest otolith growth, although age was validated for individuals that were not exposed to 14C-depleted waters to an age of at least 25 years with support for a 30-year lifespan.
It has long been argued that elections amplify partisan
predispositions. We take advantage of the timing of the
cross-national post-election surveys included in the Comparative
Study of Electoral Systems to explore the effects that elections
have on individuals’ attachments to political parties. Within these
surveys, under the assumption that the dates on which respondents
are interviewed are assigned independent of factors known to affect
partisanship, we are able to identify the causal effects of election
salience on partisan attachments. We find strong evidence that
election salience increases the probability of one having a party
attachment, increases the strength of attachments, and heightens the
relationship between partisanship and evaluations of political
actors. Empirical explorations of our identifying assumption bolster
its validity. Our results substantiate the causal role that
elections play in activating partisanship.
Prior research demonstrated that attention-deficit hyperactivity disorder (ADHD) is associated with binge-eating behavior, binge-eating disorder (BED), and bulimia nervosa (BN). The aim of this study was to investigate these associations in an adult twin population, and to determine the extent to which ADHD symptoms and binge-eating behavior share genetic and environmental factors.
Methods
We used self-reports of current ADHD symptoms and lifetime binge-eating behavior and associated characteristics from a sample of over 18 000 adult twins aged 20–46 years, from the population-based Swedish Twin Registry. Mixed-effects logistic regression was used to examine the association between ADHD and lifetime binge-eating behavior, BED, and BN. Structural equation modeling was used in 13 773 female twins to determine the relative contribution of genetic and environmental factors to the association between ADHD symptoms and binge-eating behavior in female adult twins.
Results
ADHD symptoms were significantly associated with lifetime binge-eating behavior, BED, and BN. The heritability estimate for current ADHD symptoms was 0.42 [95% confidence interval (CI) 0.41–0.44], and for lifetime binge-eating behavior 0.65 (95% CI 0.54–0.74). The genetic correlation was estimated as 0.35 (95% CI 0.25–0.46) and the covariance between ADHD and binge-eating behavior was primarily explained by genetic factors (91%). Non-shared environmental factors explained the remaining part of the covariance.
Conclusions
The association between adult ADHD symptoms and binge-eating behavior in females is largely explained by shared genetic risk factors.
With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.
Advanced paternal age at childbirth is associated with psychiatric disorders in offspring, including schizophrenia, bipolar disorder and autism. However, few studies have investigated paternal age's relationship with eating disorders in offspring. In a large, population-based cohort, we examined the association between paternal age and offspring eating disorders, and whether that association remains after adjustment for potential confounders (e.g. parental education level) that may be related to late/early selection into fatherhood and to eating disorder incidence.
Method
Data for 2 276 809 individuals born in Sweden 1979–2001 were extracted from Swedish population and healthcare registers. The authors used Cox proportional hazards models to examine the effect of paternal age on the first incidence of healthcare-recorded anorexia nervosa (AN) and all eating disorders (AED) occurring 1987–2009. Models were adjusted for sex, birth order, maternal age at childbirth, and maternal and paternal covariates including country of birth, highest education level, and lifetime psychiatric and criminal history.
Results
Even after adjustment for covariates including maternal age, advanced paternal age was associated with increased risk, and younger paternal age with decreased risk, of AN and AED. For example, the fully adjusted hazard ratio for the 45+ years (v. the 25–29 years) paternal age category was 1.32 [95% confidence interval (CI) 1.14–1.53] for AN and 1.26 (95% CI 1.13–1.40) for AED.
Conclusions
In this large, population-based cohort, paternal age at childbirth was positively associated with eating disorders in offspring, even after adjustment for potential confounders. Future research should further explore potential explanations for the association, including de novo mutations in the paternal germline.
Relapse is distressingly common after the first episode of psychosis, yet it is poorly understood and difficult to predict. Investigating changes in cognitive function preceding relapse may provide new insights into the underlying mechanism of relapse in psychosis. We hypothesized that relapse in fully remitted first-episode psychosis patients was preceded by working memory deterioration.
Method
Visual memory and verbal working memory were monitored prospectively in a 1-year randomized controlled trial of remitted first-episode psychosis patients assigned to medication continuation (quetiapine 400 mg/day) or discontinuation (placebo). Relapse (recurrence of positive symptoms of psychosis), visual (Visual Patterns Test) and verbal (Letter–Number span test) working memory and stressful life events were assessed monthly.
Results
Remitted first-episode patients (n = 102) participated in the study. Relapsers (n = 53) and non-relapsers (n = 49) had similar baseline demographic and clinical profiles. Logistic regression analyses indicated relapse was associated with visual working memory deterioration 2 months before relapse [odds ratio (OR) 3.07, 95% confidence interval (CI) 1.19–7.92, P = 0.02], more stressful life events 1 month before relapse (OR 2.11, 95% CI 1.20–3.72, P = 0.01) and medication discontinuation (OR 5.52, 95% CI 2.08–14.62, P = 0.001).
Conclusions
Visual working memory deterioration beginning 2 months before relapse in remitted first-episode psychosis patients (not baseline predictor) may reflect early brain dysfunction that heralds a psychotic relapse. The deterioration was found to be unrelated to a worsening of psychotic symptoms preceding relapse. Testable predictors offer insight into the brain processes underlying relapse in psychosis.
Debris and pyroclastic flows often have bouldery flow fronts, which act as a natural dam resisting further advance. Counter intuitively, these resistive fronts can lead to enhanced run-out, because they can be shouldered aside to form static levees that self-channelise the flow. At the heart of this behaviour is the inherent process of size segregation, with different sized particles readily separating into distinct vertical layers through a combination of kinetic sieving and squeeze expulsion. The result is an upward coarsening of the size distribution with the largest grains collecting at the top of the flow, where the flow velocity is greatest, allowing them to be preferentially transported to the front. Here, the large grains may be overrun, resegregated towards the surface and recirculated before being shouldered aside into lateral levees. A key element of this recirculation mechanism is the formation of a breaking size-segregation wave, which allows large particles that have been overrun to rise up into the faster moving parts of the flow as small particles are sheared over the top. Observations from experiments and discrete particle simulations in a moving-bed flume indicate that, whilst most large particles recirculate quickly at the front, a few recirculate very slowly through regions of many small particles at the rear. This behaviour is modelled in this paper using asymmetric segregation flux functions. Exact non-diffuse solutions are derived for the steady wave structure using the method of characteristics with a cubic segregation flux. Three different structures emerge, dependent on the degree of asymmetry and the non-convexity of the segregation flux function. In particular, a novel ‘lens-tail’ solution is found for segregation fluxes that have a large amount of non-convexity, with an additional expansion fan and compression wave forming a ‘tail’ upstream of the ‘lens’ region. Analysis of exact solutions for the particle motion shows that the large particle motion through the ‘lens-tail’ is fundamentally different to the classical ‘lens’ solutions. A few large particles starting near the bottom of the breaking wave pass through the ‘tail’, where they travel in a region of many small particles with a very small vertical velocity, and take significantly longer to recirculate.
Preterm birth may be spontaneous or medically indicated for maternal or fetal reasons. Around 20–25% of preterm births (PTB) follow preterm premature rupture of the membranes (PPROM), however the cause of preterm labour is often unknown. It may represent early maturation and activation of the normal labour process or it may be precipitated by pathological causes. The normal process of labour has a diurnal variation with more deliveries occurring at night. Evidence demonstrating that the diurnal variation persists in preterm deliveries suggest that at least a proportion are due to early maturation of the normal process and the logical assumption is that these may be amenable to prevention or effective treatment. Whatever the cause of preterm delivery, there appears to be a common pathway resulting in activation of inflammatory processes. It is important to distinguish the physiological and pathological causes of preterm labour and not to assume that all inflammation is pathological. The distinction is clinically important since pathological causes may be associated with an adverse intrauterine environment, which would be a contraindication to delaying delivery.
Particle-size segregation can have a significant feedback on the bulk motion of granular avalanches when the larger grains experience greater resistance to motion than the fine grains. When such segregation-mobility feedback effects occur the flow may form digitate lobate fingers or spontaneously self-channelize to form lateral levees that enhance run-out distance. This is particularly important in geophysical mass flows, such as pyroclastic currents, snow avalanches and debris flows, where run-out distance is of crucial importance in hazards assessment. A model for finger formation in a bidisperse granular avalanche is developed by coupling a depth-averaged description of the preferential transport of large particles towards the front with an established avalanche model. The coupling is achieved through a concentration-dependent friction coefficient, which results in a system of non-strictly hyperbolic equations. We compute numerical solutions to the flow of a bidisperse mixture of small mobile particles and larger more resistive grains down an inclined chute. The numerical results demonstrate that our model is able to describe the formation of a front rich in large particles, the instability of this front and the subsequent evolution of elongated fingers bounded by large-rich lateral levees, as observed in small-scale laboratory experiments. However, our numerical results are grid dependent, with the number of fingers increasing as the numerical resolution is increased. We investigate this pathology by examining the linear stability of a steady uniform flow, which shows that arbitrarily small wavelength perturbations grow exponentially quickly. Furthermore, we find that on a curve in parameter space the growth rate is unbounded above as the wavelength of perturbations is decreased and so the system of equations on this curve is ill-posed. This indicates that the model captures the physical mechanisms that drive the instability, but additional dissipation mechanisms, such as those considered in the realm of flow rheology, are required to set the length scale of the fingers that develop.
We investigated an international outbreak of Salmonella Agona with a distinct PFGE pattern associated with an Irish Food company (company X) producing pre-cooked meat products sold in various food outlet chains in Europe. The outbreak was first detected in Ireland. We undertook national and international case-finding, food traceback and microbiological investigation of human, food and environmental samples. We undertook a matched case-control study on Irish cases. In total, 163 cases in seven European countries were laboratory-confirmed. Consumption of food from food outlet chains supplied by company X was significantly associated with being a confirmed case (mOR 18·3, 95% CI 2·2–149·2) in the case-control study. The outbreak strain was isolated from the company's pre-cooked meat products and production premises. Sufficient evidence was gathered to infer the vehicles of infection and sources of the outbreak and to justify the control measures taken, which were plant closure and food recall.
To determine the frequency of cholesteatoma in a population of patients with chronic suppurative otitis media, and to determine whether this frequency is affected by ethnicity.
Patients:
The study included 6005 patients with chronic suppurative otitis media seen during the course of 30 charitable surgical ‘ear camps’ in Nepal.
Main outcome measures:
Proportion of patients with each subtype of disease, and their ethnicity. A secondary outcome measure was concordance of surname with Nepalese ethnic affiliation.
Results:
A total of 762 patients were grouped as being of Tibeto-Mongolian origin, and 4875 as Indo-Caucasian. The rate of chronic suppurative otitis media with cholesteatoma, expressed as a proportion of the rate of all chronic suppurative otitis media subtypes, was 17.8 per cent in Tibeto-Mongolian patients and 18.6 per cent in Indo-Caucasian patients (p > 0.05). The effect of other risk factors (i.e. age, gender and geographical district) on disease distribution was also non-significant. Analysis of secondary outcome measures indicated that patients' surnames were a reliable predictor of ethnicity in this Nepalese population.
Conclusion:
There is almost complete concordance in proportions of patients with significant genetic, cultural, and even geographical heterogeneity, suggesting that, in Nepal, the aetiology of cholesteatoma owes little to these factors.