14 resultados para Representative Core Samples

em Deakin Research Online - Australia


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The infaunal bivalve Soletellina alba is susceptible to mass mortalities during annual winter flooding in the Hopkins River Estuary, southern Australia. Periods of low salinity (≤1) are the likely cause of these mass mortality events, which can occur in seasonally-closed estuaries when high winter flows are sufficient to flush all salt water from the estuary. Core samples of S. alba were collected from two water depths across four times and at three sites near the mouth of the estuary. Minimal to zero abundances of large S. alba (>1 mm) were expected to be sampled, particularly at the shallower water depth, during a typical winter flood event. However, the present study occurred during a period of drought, which led to the absence of winter flooding. This absence of winter flooding prevented the occurrence of lethal salinities (i.e. ≤1) in the estuary during this period and a greater number of living S. alba adults were sampled. Abundances of juvenile and adult S. alba were still variable, even in the absence of winter flooding, and reflected an interaction between date, site and water depth. However, no mass mortalities of adults were observed during the drought conditions in contrast to what occurs during typical winter flood events and provides support for the hypothesis that winter flooding is responsible for past mass mortalities.

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This article compares prevalence estimates of substance use and  delinquent behavior in Washington State, United States and Victoria, Australia, two states chosen for their different policy environments around problem behavior. Few comparisons of international differences on rates of multiple problem behavior exist, and most are based on methods that are not matched, raising the question of whether findings are based on  methodological differences rather than actual rate differences. The  International Youth Development Study used standardized methods to recruit and administer an adaptation of the Communities That Care Youth Survey to representative state samples of fifth-, seventh-, and ninth-grade students in each state. Rates of delinquent behavior were generally comparable.  However, striking differences in substance use were noted, with Victoria students reporting higher rates of alcohol use, alcohol misuse, smoking, and inhalant use, whereas Washington State students reported higher rates of marijuana use. Implications for conducting international comparisons are discussed.

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OBJECTIVE We examined associations between pubertal stage and violent adolescent behavior and social/relational aggression.

METHODS
The International Youth Development Study comprises statewide representative student samples in grades 5, 7, and 9 (N = 5769) in Washington State and Victoria, Australia, drawn as a 2-stage cluster sample in each state. We used a school-administered, self-report student survey to measure previous-year violent behavior (ie, attacking or beating up another person) and social/relational aggression (excluding peers from the group, threatening to spread lies or rumors), as well as risk and protective factors and pubertal development. Cross-sectional data were analyzed.

RESULTS Compared with early puberty, the odds of violent behavior were approximately threefold higher in midpuberty (odds ratio [OR]: 2.87 [95% confidence interval (CI): 1.81–4.55]) and late puberty (OR: 3.79 [95% CI: 2.25–6.39]) after adjustment for demographic factors. For social/relational aggression, there were weaker overall associations after adjustment, but these associations included an interaction between pubertal stage and age, and stronger associations with pubertal stage at younger age were shown (P = .003; midpuberty OR: 1.78 [95% CI: 1.20–2.63]; late puberty OR: 3.00 [95% CI: 1.95–4.63]). Associations between pubertal stage and violent behavior and social/relational aggression remained after the inclusion of social contextual mediators in the analyses.

CONCLUSIONS
Pubertal stage was associated with higher rates of violent behavior and social/relational aggression, with the latter association seen only at younger ages. Puberty is an important phase at which to implement prevention programs to reduce adolescent violent and antisocial behaviors.

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Estimating the accessible prey fraction for short-billed waders, we used a new sampling device - the sediment- plane( Desholme t al. 1998) - to record prey density of the uppermost benthos communities in softbottom habitats. In contrast to "ordinary"core-samplers, the sediment plane allows a relatively quick sampling of the uppermost layers of the sediment and, thus, it should allow a more reliable estimate of the accessible benthos community especially of vertically mobile prey organisms such as polychaetes. To assess its usefulness, we compared samples collected with the sediment-plane that took only the uppermost 3cm of the sediment with samples taken with a core-sampler. These investigations showed significant differences between the two sampling methods. In comparison with the corresponding layer of the core samples, we found significantly higher numbers and a higher biomass for at least four polychaete species (e.g. Ragworm Nereis diversicolor) in the plane samples.Therefore, we recommend the use of the sediment-plane when studying the accessible fraction for foraging waders especially when studying short-billed species.

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To investigate the cross-national relevance of community health promotion, this paper compared community variation in alcohol use and risk and protective factors for adolescents in Australia (State of Victoria, 2009) and the Netherlands (2007/2008). Multi-level analyses examined community variation in heavy episodic (binge) alcohol use [≥5 drinks in a session ≥once in the prior fortnight (>63 ml of ethanol)] and associations with predictors. Representative community samples of adolescents (12–17 years) were recruited. The participants were 7812 students from 36 Australian communities and 15 082 adolescents from 124 Dutch communities. Predictors included adolescent reports of family, school, peer and neighbourhood environments and community predictors (rural, disadvantage). The overall prevalence of alcohol use prevalence was similar in both nations. Australia had higher use at younger ages and no difference between genders. In the Netherlands older adolescents and males used alcohol at significantly higher rates. Although individual predictors were mostly similar, binge drinking was more strongly associated with poor family management, friends' use of drugs and community disorganization in Australia. Significant community variation in adolescent heavy alcohol use was observed in both countries, but was higher in the Netherlands [inter class correlation 6.1%, (95% CI: 4.5–8.3%)] than Australia (ICC 2.4%, 1.3–4.5%). Youth from rural areas drank at a higher level, especially in the Netherlands. Targeting community level adolescent alcohol use appears feasible in both countries. Although behavioural patterns and risk and protective influences are similar in the Netherlands and Australia, important differences should be taken into account in tailoring community interventions.

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The food resource hypothesis of breeding habitat selection in beach-nesting birds suggests that birds breed at sites with more prey to meet the increased energetic requirements associated with breeding. We compare prey resources using pitfall traps and core samples at breeding sites and absence sites of the eastern population of hooded plover, Thinornis rubricollis rubricollis, which, in this part of its range, is a threatened obligate beach bird. Breeding sites had higher abundances, equivalent species richness, and different assemblages of invertebrate prey compared with absence sites. Assemblages at breeding sites were characterised by more isopods, and fewer beetles of the family Phycosecidae. Breeding habitat selection by plovers appears to be associated with selection for sites with more food, and any process that degrades food resources at a site (e.g. kelp harvesting or marine pollution events) may reduce the likelihood of occupancy of that site by breeding birds.

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PURPOSE: Preventable patient harm due to adverse events (AEs) is a significant health problem today facing contemporary health care. Knowledge of patients' experiences of AEs is critical to improving health care safety and quality. A systematic review of studies of patients' experiences of AEs was conducted to report their experiences, knowledge gaps and any challenges encountered when capturing patient experience data. DATA SOURCES: Key words, synonyms and subject headings were used to search eight electronic databases from January 2000 to February 2015, in addition to hand-searching of reference lists and relevant journals. STUDY SELECTION: Titles and abstracts of publications were screened by two reviewers and checked by a third. Full-text articles were screened against the eligibility criteria. DATA EXTRACTION: Data on design, methods and key findings were extracted and collated. RESULTS: Thirty-three publications demonstrated patients identifying a range of problems in their care; most commonly identified were medication errors, communication and coordination of care problems. Patients' income, education, health burden and marital status influence likelihood of reporting. Patients report distress after an AE, often exacerbated by receiving inadequate information about the cause. Investigating patients' experiences is hampered by the lack of large representative patient samples, data over sufficient time periods and varying definitions of an AE. CONCLUSION: Despite the emergence of policy initiatives to enhance patient engagement, few studies report patients' experiences of AEs. This information must be routinely captured and utilized to develop effective, patient-centred and system-wide policies to minimize and manage AEs.

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To predict current and future body mass index (BMI) and prevalence of overweight and obesity in Australian children and adults based on sex, age and year of birth (cohort). These predictions are needed for population health planning and evaluation. Data were drawn from 11 cross-sectional national or state population surveys conducted in Australia between 1969 and 2004. These included representative population samples of children (n= 27,635) and adults (n= 43,447) aged 5 years or older with measured height and weight data. Multiple linear regression analyses of measured log-transformed BMI data were conducted to determine the independent effects of age and year of birth (cohort) on ln(BMI) for males and females, respectively. Regression coefficients for cohort obtained from these analyses were applied to the National Nutrition Survey 1995 data set to predict mean BMI and prevalence of overweight (BMI 25-29.99 kg/m(2)) and obesity (BMI ≥ 30 kg/m(2)) in 2005, 2015 and 2025. Based on past trends, BMI is predicted to continue to increase for both males and females and across the age span. This would result in increases in the prevalence of overweight and obesity of between 0.4 and 0.8% per year, such that by 2025 around one-third of 5-19 year olds will be overweight or obese as will 83% of males and 75% of females aged 20 years and over. The increases in prevalence and mean BMI predicted in this study will have significant impacts on disease burden, healthcare costs and need for prevention and treatment programmes.

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The establishment of a system of protected areas that samples all ecosystems, including freshwater environments, in a comprehensive, adequate and representative (CAR) manner is regarded as a cornerstone for the conservation of biodiversity. There have been few quantitative assessments of the comprehensiveness, adequacy and representativeness of freshwater reserves in Australia. This paper reviews and quantifies the effect of classification of freshwater ecosystems for conservation planning, the importance of reservation status and protection measures for developing a CAR reserve system, and aspects of reserve design for freshwater ecosystems. We propose a strategic and iterative process that incorporates these measures to assist in the efficient and effective development of freshwater reserve systems worldwide. However, the provision of suitable water regimes for freshwater reserves presents further ecological and political challenges, and even adequate reservation of freshwater ecosystems may not conserve constituent biodiversity without effective management.

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Although youth drug and alcohol harm minimization policies in Australia are often contrasted with the abstinence and zero tolerance policies adopted in the United States, there has been little research directly comparing youth substance use behaviour in the two countries. Three state representative samples in Victoria, Australia (n = 7898) and in the US states of Oregon (n = 15 224) and Maine (n = 16 245) completed a common cross-sectional student survey. Rates of alcohol use (lifetime alcohol use, recent use in the past 30 days), alcohol use exceeding recommended consumption limits (binge drinking: five or more drinks in a session), other licit drug use (tobacco use), and norm-violating substance use (substance use at school, use in the past 30 days of marijuana or other illicit drug use) were compared for males and females at ages 12-17. Rates were lower (odds ratios 0.5-0.8) for youth in Maine and Oregon compared to Victoria for lifetime and recent alcohol use, binge drinking and daily cigarette smoking. However, rates of recent marijuana use and recent use of other illicit drugs were higher in Maine and Oregon, as were reports of being drunk or high at school. In contradiction of harm minimization objectives, Victoria, relative to the US states of Oregon and Maine, demonstrated higher rates of alcohol use exceeding recommended consumption limits and daily tobacco use. However, findings suggested that aspects of norm-violating substance use (substance use at school, marijuana use and other illicit drug use) were higher in the US states compared to Victoria.

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Introduction Improving infrastructure to support walking and cycling is often regarded as fundamental to encouraging their widespread uptake. However, there is little evidence that specific provision of this kind has led to a significant increase in walking or cycling in practice, let alone wider impacts such as changes in overall physical activity or carbon emissions. Connect2 is a major new project that aims to promote walking and cycling in the UK by improving local pedestrian and cycle routes. It therefore provides a useful opportunity to contribute new evidence in this field by means of a natural experimental study.

Methods and analysis iConnect is an independent study that aims to integrate the perspectives of public health and transport research on the measurement and evaluation of the travel, physical activity and carbon impacts of the Connect2 programme. In this paper, the authors report the study design and methods for the iConnect core module. This comprised a cohort study of residents living within 5 km of three case study Connect2 projects in Cardiff, Kenilworth and Southampton, supported by a programme of qualitative interviews with key informants about the projects. Participants were asked to complete postal questionnaires, repeated before and after the opening of the new infrastructure, which collected data on demographic and socioeconomic characteristics, travel, car fuel purchasing and physical activity, and potential psychosocial and environmental correlates and mediators of those behaviours. In the absence of suitable no-intervention control groups, the study design drew on heterogeneity in exposure both within and between case study samples to provide for a counterfactual.

Ethics and dissemination The study was approved by the University of Southampton Research Ethics Committee. The findings will be disseminated through academic presentations, peer-reviewed publications and the study website (http://www.iconnect.ac.uk) and by means of a national seminar at the end of the study.

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Rapid growth of technical developments has created huge challenges for microphone forensics - a sub-category of audio forensic science, because of the availability of numerous digital recording devices and massive amount of recording data. Demand for fast and efficient methods to assure integrity and authenticity of information is becoming more and more important in criminal investigation nowadays. Machine learning has emerged as an important technique to support audio analysis processes of microphone forensic practitioners. However, its application to real life situations using supervised learning is still facing great challenges due to expensiveness in collecting data and updating system. In this paper, we introduce a new machine learning approach which is called One-class Classification (OCC) to be applied to microphone forensics; we demonstrate its capability on a corpus of audio samples collected from several microphones. In addition, we propose a representative instance classification framework (RICF) that can effectively improve performance of OCC algorithms for recording signal with noise. Experiment results and analysis indicate that OCC has the potential to benefit microphone forensic practitioners in developing new tools and techniques for effective and efficient analysis.

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Aim: Tracking the dispersal patterns and habitat use of migratory species is necessary to delineate optimal areas for protection, with large sample sizes being more representative of the population. Here, we examine the dispersal patterns of a key Mediterranean loggerhead turtle (Caretta caretta) breeding population to identify priority foraging sites for protection. Location: Zakynthos Island, Greece and the wider Mediterranean. Method: We examined the dispersal patterns and foraging sites of 75 adult loggerheads (n = 38 males and 37 females) tracked from the breeding area of Zakynthos Island (Greece) from 2004 to 2011. We then combined our data with published sea turtle literature to identify key foraging sites for protection. Results: While both males and females exhibited similar dispersal patterns, about 25% males remained < 100 km of Zakynthos, whereas all females (except one) migrated > 200 km. Integration of our data with the wider literature isolated 10 core sites in proximity to existing protected areas, which could potentially protect 64% of the Zakynthos population, while five sites support individuals from at least 10 other loggerhead breeding populations. Main conclusions: Due to the widespread availability of neritic foraging grounds across the Mediterranean, sea turtles from Zakynthos exhibit disparate dispersal patterns. However, protecting only a few objectively defined important sites can encompass a large proportion of the foraging areas used and hence have considerable conservation benefit.

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Conversational samples were collected from 34 nondisabled subjects across four worksites. The total sample was analyzed for core vocabulary, and the five most frequently referenced topics were analyzed for core and fringe vocabularies and the commonality of fringe vocabulary across topics. The results indicated that there was a small stable core vocabulary of 347 words containing words unique to this study, which accounted for 78% of the conversational sample. A total of 21 words in the fringe vocabulary was common to all topics. Implications of this study for vocabulary selection for augmented communicators in employment are discussed.