169 resultados para 151-907
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Existing evidence for successful silvicultural control of Hypsipyla spp. is conflicting and to a large extent anecdotal. Levels of attack have been correlated with factors such as shade, planting density, species mixtures, site characteristics, etc. These factors have often been poorly defined and are usually interdependent. The actual mechanisms that determine whether or not Hypsipyla spp. adversely affects plants we define as host-finding, host suitability, host recovery and natural enemies. These mechanisms can be influenced by the silvicultural techniques applied to a stand. Success of silvicultural techniques can usually be attributed to more than one mechanism and it is difficult to assess which is most the important for minimising the impact of Hypsipyla as these analytical data are lacking. This highlights the need for further research on silvicultural methods for controlling Hypsipyla spp. However, several silvicultural techniques that are briefly described show promise for improving the performance of future plantations. Examples of silvicultural control are reviewed with reference to these mechanisms.
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Background The koala, Phascolarctos cinereus, is a biologically unique and evolutionarily distinct Australian arboreal marsupial. The goal of this study was to sequence the transcriptome from several tissues of two geographically separate koalas, and to create the first comprehensive catalog of annotated transcripts for this species, enabling detailed analysis of the unique attributes of this threatened native marsupial, including infection by the koala retrovirus. Results RNA-Seq data was generated from a range of tissues from one male and one female koala and assembled de novo into transcripts using Velvet-Oases. Transcript abundance in each tissue was estimated. Transcripts were searched for likely protein-coding regions and a non-redundant set of 117,563 putative protein sequences was produced. In similarity searches there were 84,907 (72%) sequences that aligned to at least one sequence in the NCBI nr protein database. The best alignments were to sequences from other marsupials. After applying a reciprocal best hit requirement of koala sequences to those from tammar wallaby, Tasmanian devil and the gray short-tailed opossum, we estimate that our transcriptome dataset represents approximately 15,000 koala genes. The marsupial alignment information was used to look for potential gene duplications and we report evidence for copy number expansion of the alpha amylase gene, and of an aldehyde reductase gene. Koala retrovirus (KoRV) transcripts were detected in the transcriptomes. These were analysed in detail and the structure of the spliced envelope gene transcript was determined. There was appreciable sequence diversity within KoRV, with 233 sites in the KoRV genome showing small insertions/deletions or single nucleotide polymorphisms. Both koalas had sequences from the KoRV-A subtype, but the male koala transcriptome has, in addition, sequences more closely related to the KoRV-B subtype. This is the first report of a KoRV-B-like sequence in a wild population. Conclusions This transcriptomic dataset is a useful resource for molecular genetic studies of the koala, for evolutionary genetic studies of marsupials, for validation and annotation of the koala genome sequence, and for investigation of koala retrovirus. Annotated transcripts can be browsed and queried at http://koalagenome.org
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During the last decade 'prostitution' has been characterised as a 'social problem' throughout rural and regional New South Wales. As we show here, the urban-centric nature of popular and official discourses of prostitution have inadvertently allowed for the development of regulatory positions which have negatively impacted sex workers in rural and regional communities and lead to conflict among sectors of the rural sex industry and between the sex industry and community activists. In addition to examining the problematisation of sex work in rural New South Wales, this paper sets out to understand why rural sex work has historically lacked visibility in popular and scholarly discourses. We provide an overview of the distinctive organisational aspects of the sex industry in rural contexts. Evidence for our assertions is largely derived from primary interview data collected from sex industry workers based in rural New South Wales. The paper represents the first attempt in the research literature on prostitution to understand sex work as a rural phenomenon.
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Calls from 14 species of bat were classified to genus and species using discriminant function analysis (DFA), support vector machines (SVM) and ensembles of neural networks (ENN). Both SVMs and ENNs outperformed DFA for every species while ENNs (mean identification rate – 97%) consistently outperformed SVMs (mean identification rate – 87%). Correct classification rates produced by the ENNs varied from 91% to 100%; calls from six species were correctly identified with 100% accuracy. Calls from the five species of Myotis, a genus whose species are considered difficult to distinguish acoustically, had correct identification rates that varied from 91 – 100%. Five parameters were most important for classifying calls correctly while seven others contributed little to classification performance.
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It is well understood that that there is variation inherent in all testing techniques, and that all soil and rock materials also contain some degree of natural variability. Less consideration is normally given to variation associated with natural material heterogeneity within a site, or the relative condition of the material at the time of testing. This paper assesses the impact of spatial and temporal variability upon repeated insitu testing of a residual soil and rock profile present within a single residential site over a full calendar year, and thus range of seasonal conditions. From this repeated testing, the magnitude of spatial and temporal variation due to seasonal conditions has demonstrated that, depending on the selected location and moisture content of the subsurface at the time of testing, up to a 35% variation within the test results can be expected. The results have also demonstrated that the completed insitu test technique has a similarly large measurement and inherent variability error and, for the investigated site, up to a 60% variation in normalised results was observed. From these results, it is recommended that the frequency and timing of insitu tests should be considered when deriving geotechnical design parameters from a limited data set.
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Background Unlike leisure time physical activity, knowledge of the socioeconomic determinants of active transport is limited, research on this topic has produced mixed and inconsistent findings, and it remains unknown if peoples’ engagement in active transport declines as they age. This longitudinal study examined relationships between neighbourhood disadvantage, individual-level socioeconomic position and walking for transport (WfT) during mid- and early old-age (40 – 70 years). Three questions were addressed: (i) which socioeconomic groups walk for transport, (ii) does the amount of walking change over time as people age, and (iii) is the change socioeconomically patterned? Methods The data come from the HABITAT study of physical activity, a bi-annual multilevel longitudinal survey of 11,036 residents of 200 neighbourhoods in Brisbane, Australia. At each wave (2007, 2009 and 2011) respondents estimated the duration (minutes) of WfT in the previous 7 days. Neighbourhood disadvantage was measured using a census-derived index comprising 17 different socioeconomic components, and individual-level socioeconomic position was measured using education, occupation, and household income. The data were analysed using multilevel mixed-effects logistic and linear regression. Results The odds of being defined as a ‘never walker’ were significantly lower for residents of disadvantaged neighbourhoods, but significantly higher for the less educated, blue collar employees, and members of lower income households. WfT declined significantly over time as people aged and the declines were more precipitous for older persons. Average minutes of WfT declined for all neighbourhoods and most socioeconomic groups; however, the declines were steeper for the retired and members of low income households. Conclusions Designing age-friendly neighbourhoods might slow or delay age-related declines in WfT and should be a priority. Steeper declines in WfT among residents of low income households may reflect their poorer health status and the impact of adverse socioeconomic exposures over the life course. Each of these declines represents a significant challenge to public health advocates, urban designers, and planners in their attempts to keep people active and healthy in their later years of life.
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QLD, 4Murri Health Group, Caboolture, QLD Introduction Respiratory illnesses with cough as a symptom are predominant causes of morbidity in young Australian Indigenous children. With the exception of ear disease, there are limited studies that have addressed burden and outcome. Also, there are no studies that are specific to urban Indigenous children. Aim: We aim to comprehensively investigate the incidence, aetiology, risk factors for and outcomes of acute respiratory illnesses (ARIs) in this population. Methods A cohort study of Indigenous children aged less than 5 years registered with an urban Indigenous primary health care service. Comprehensive baseline data are collected and children are followed monthly for 12 months to capture ARI events. ARI events are subsequently followed weekly for 4 weeks to determine cough outcomes, with review by a paediatric respiratory physician if cough has not resolved within 28 days. Results To date, 58 children (57% female) have been enrolled and 46 ARIs have been captured over 907 child weeks of observation (5.1 events per 100 child weeks, 95%CI 3.7–6.8). 13 ARIs (28.3%) have resulted in persistent cough for >28 days following onset. Conclusion Our early findings suggest an excess incidence of ARI in this population. The proportion of ARIs resulting in persistent cough for more than 4 weeks is the highest yet reported. Key Words: Indigenous, acute respiratory illness, paediatric.
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Dewatering of microalgal culture is a major bottleneck towards the industrial-scale processing of microalgae for bio-diesel production. The dilute nature of harvested microalgal cultures poses a huge operation cost to dewater; thereby rendering microalgae-based fuels less economically attractive. This study explores the influence of microalgal growth phases and intercellular interactions during cultivation on dewatering efficiency of microalgae cultures. Experimental results show that microalgal cultures harvested during a low growth rate phase (LGRP) of 0.03 d-1 allowed a higher rate of settling than those harvested during a high growth rate phase (HGRP) of 0.11 d-1, even though the latter displayed a higher average differential biomass concentration of 0.2 g L-1 d-1. Zeta potential profile during the cultivation process showed a maximum electronegative value of -43.2 ± 0.7 mV during the HGRP which declined to stabilization at -34.5 ± 0.4 mV in the LGRP. The lower settling rate observed for HGRP microalgae is hence attributed to the high stability of the microalgal cells which electrostatically repel each other during this growth phase. Tangential flow filtration of 20 L HGRP culture concentrated 23 times by consuming 0.51 kWh/m3 of supernatant removed whilst 0.38 kWh/m3 was consumed to concentrate 20 L of LGRP by 48 times.
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We analyse the security of iterated hash functions that compute an input dependent checksum which is processed as part of the hash computation. We show that a large class of such schemes, including those using non-linear or even one-way checksum functions, is not secure against the second preimage attack of Kelsey and Schneier, the herding attack of Kelsey and Kohno and the multicollision attack of Joux. Our attacks also apply to a large class of cascaded hash functions. Our second preimage attacks on the cascaded hash functions improve the results of Joux presented at Crypto’04. We also apply our attacks to the MD2 and GOST hash functions. Our second preimage attacks on the MD2 and GOST hash functions improve the previous best known short-cut second preimage attacks on these hash functions by factors of at least 226 and 254, respectively. Our herding and multicollision attacks on the hash functions based on generic checksum functions (e.g., one-way) are a special case of the attacks on the cascaded iterated hash functions previously analysed by Dunkelman and Preneel and are not better than their attacks. On hash functions with easily invertible checksums, our multicollision and herding attacks (if the hash value is short as in MD2) are more efficient than those of Dunkelman and Preneel.
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Introduction to Youth Services is a second year Social Work and Human Services unit. In this unit a reflective writing task was introduced to assess students’ reflections on an ongoing tutorial discussion to which they contributed. The discussion was based on a fictional young person each tutorial group ‘worked with’ across eight weeks of a semester. In developing the process and the criteria for the reflective journal, the ideas raised by the Teaching and Assessing Reflective Learning (TARL) in Higher Education project (see Chap. 2) were utilised, scaffolding the work with resources and submission of a draft. The students were also invited to choose the form of reflective process they used, it could be a written journal but did not need to be. The evidence exemplified that a reflective journal is an effective tool for students to record their developing understanding regarding the concept that issues people experience are complex and compounding. Importantly, it was also a useful vehicle for students to begin to consider the impacts of their own and others’ values and beliefs on their response to the issues raised within the case discussion. The reflective journal also helped participants to consider how this learning contributes to the ongoing development of their professional practice framework.
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Research on subtle dehumanization has focused on the attribution of human uniqueness to groups (infrahumanization), but has not examined another sense of humanness, human nature. Additionally, research has not extended far beyond Western cultures to examine the universality of these forms of dehumanization. Hence, the attribution of both forms of humanness was examined in three cross-cultural studies. Anglo-Australian and ethnic Chinese attributed values and traits (Study 1, N = 200) and emotions (Study 2, N = 151) to Australian and Chinese groups, and rated these characteristics on human uniqueness and human nature. Both studies found evidence of complementary attributions of humanness for Australians, who denied Chinese human nature but attributed them with greater human uniqueness. Chinese denied Australians human uniqueness, but their attributions of human nature varied for traits, values, and emotions. Study 3 (N = 54) demonstrated similar forms of dehumanization using an implicit method. These results and their implications for dehumanization and prejudice suggest the need to broaden investigation and theory to encompass both forms of humanness, and examine the attribution of both lesser and greater humanness to outgroups.
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This report is the first systematic analysis of employment in the UK’s creative and high-tech economies. It analyses their size, growth and distribution across the country. Key Findings • The UK’s creative economy had 2.6 million jobs in 2013, consisting of 1.7 million jobs in the creative industries (890,000 in creative occupations and 818,000 working in other roles) and 907,000 jobs in creative occupations outside of the creative industries. • The UK’s high–tech economy had 3.2 million jobs in 2013, 2.4 million of which were jobs in high–tech industries (825,000 in Science Technology Engineering and Mathematics (STEM) occupations and 1.6 million in other roles) and 806,000 jobs in STEM occupations outside of the high–tech industries. • Employment in the creative economy grew on average over three times faster than the workforce as a whole (4.3 per cent per annum (p.a.) vs 1.2 per cent p.a.) between 2011 and 2013. • Employment in the high–tech economy also grew faster than the workforce over this period (2.1 per cent p.a. vs 1.2 per cent p.a.). • The creative economy is particularly concentrated in London and the South East which together account for 43 per cent of the UK’s creative economy workforce. By contrast, 31 per cent of high-tech economy employment and 28 per cent of the UK’s workforce is located in this area.
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Many drivers and non-cyclists perceive cycling as an extremely risky activity with women in particular being concerned about the risk of injury. The low rates of cycling participation by women pose a threat to the achievement of government targets for cycling participation and restrict the potential transport, health and environmental benefits that increased levels of cycling could provide. This study seeks to extend earlier research in gender and cycling by comparing the risks perceived by female and male cyclists and drivers in specific on-road situations while accounting for other potentially gender-related factors such as travel patterns and experience, perceived skill, and risk taking behaviors. In an online survey, 444 regular cyclists and 151 (non-cyclist) car drivers rated the level of risk in six situations: Failing to yield; Going through a red light; Not signaling when turning; Swerving; Tailgating; and Not checking traffic. The study found that the higher levels of risk perceived by women are not completely accounted for by differences in cycling patterns or perceptions of skill. Compared to their male counterparts, female cyclists and car drivers had similarly elevated perceptions of risk suggesting that these gender differences are not specific to cycling, but reflect wider differences in risk perception. Not all of the gender differences were consistent across cyclists and drivers. Higher levels of perceived skill were evident for male cyclists but not for male car drivers. Further research is needed to explore the robustness and interpretation of this finding.