161 research outputs found

    Productivity Measurements of Two Waratah 234 Hydraulic Tree Harvesters in Radiata Pine in New Zealand

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    Two Waratah 234 single-grip harvester heads were assessed for productivity and log-processing accuracy while working in radiata pine clearfell operations in New Zealand forests. Estimated productivity, processing stockpiled trees into logs on a landing in a ground-based operation, was 77 m3 per productive machine hour (PMH) in an average tree size of 1.63 m3. In a yarder-based trial, processing trees into logs on a landing, productivity was 77 m3 / PMH in an average tree size of 3.1 m3. Length-measuring accuracy in a later trial was shown to be within ± 5 cm for 93% of logs. In a second ground-based trial, estimated productivity for an average extracted tree size of 1.95m3 was: - 51 trees/PMH (100m3) for felling, tree-length delimbing and bunching. - 73 trees/PMH (143m3) for tree-length delimbing (butt-first) and bunching of manually felled trees

    Analysis of the Johns Hopkins Neutron Background Measurements

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    This report addresses the analysis of the Johns Hopkins neutron background measurements

    Inclusive School Community: Why is it so Complex?

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    This paper addresses the question: why is it so hard for school communities to respond to diversity in learners, staff and parents in inclusive ways? The authors draw on theory and recent professional experience in Queensland, Australia, to offer four guiding principles that address traditional assumptions about learning that result in inequality of opportunity and outcomes for students. The authors suggest these principles to support the development of a more inclusive school community: (1) develop a learning community incorporating a critical friend; (2) value and collaborate with parents and the broader community; (3) engage students as citizens in school review and develop¬ment; and (4) support teachers’ critical engagement with inclusive ideals and practices. The authors describe how the principles can work in concert in a school community

    Landscape change as a platform for environmental and social healing

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    Aotearoa New Zealand is characterised by dynamic landscapes. Major landscape-altering events, such as earthquakes, floods, landslides and tsunami, have deeply influenced the relationships that many Māori, the Indigenous peoples of Aotearoa New Zealand, have with their ancestral landscapes. This work documents perspectives of landscape change from five Māori individuals from various iwi (tribes) and hapū (kin groups) around Aotearoa New Zealand, who have strong ties with their tūrangawaewae (place of connection). In exercising the Māori principle of whanaungatanga, we conducted semi-structured interviews following a general inductive approach over a series of meetings. This research indicates that no matter the cause of a landscape-altering event, connections, sustainability, reciprocity and adaptability are core values to uphold. These values can be used to guide human activity and involvement pertaining to responding to the event days, months and years after. This work also indicates that altered landscapes have a natural way of healing themselves through time, and that people play an important role in defining landscape change and recovery following landscape-altering events

    The TNF-Family Receptor DR3 is Essential for Diverse T Cell-Mediated Inflammatory Diseases

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    SummaryDR3 (TRAMP, LARD, WSL-1, TNFRSF25) is a death-domain-containing tumor necrosis factor (TNF)-family receptor primarily expressed on T cells. TL1A, the TNF-family ligand for DR3, can costimulate T cells, but the physiological function of TL1A-DR3 interactions in immune responses is not known. Using DR3-deficient mice, we identified DR3 as the receptor responsible for TL1A-induced T cell costimulation and dendritic cells as the likely source for TL1A during T cell activation. Despite its role in costimulation, DR3 was not required for in vivo T cell priming, for polarization into T helper 1 (Th1), Th2, or Th17 effector cell subtypes, or for effective control of infection with Toxoplasma gondii. Instead, DR3 expression was required on T cells for immunopathology, local T cell accumulation, and cytokine production in Experimental Autoimmune Encephalomyelitis (EAE) and allergic lung inflammation, disease models that depend on distinct effector T cell subsets. DR3 could be an attractive therapeutic target for T cell-mediated autoimmune and allergic diseases

    Coping with potential bi-parental inbreeding: limited pollen and seed dispersal and large genets in the dioecious marine angiosperm Thalassia testudinum

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    The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross-fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling-mating or bi-parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back-Reef and Mid-Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by finescale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3–1.6 m (max. 4.8 m) and of seeds was 0.3–0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m² (range 3.4–11.4 m²) at Back-Reef and 1.9 (range 1.87–1.92 m²) at Mid-Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1–20.5 m² at Back-Reef and 0.1–16.9 m² at Mid-Lagoon. Maximal extensions of the genets, in 19 9 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back-Reef and Mid-Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (Fis) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back-Reef). Contrary to our expectations, we did not find evidence of bi-parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi-parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back-Reef and Mid-Lagoon, respectively); such highly dispersed guerrilla-like clonal growth form likely increases the probability of crossing between different potentially unrelated genets.Brigitta Ine Van Tussenbroek, Tania Valdivia-Carrillo, Irene Teresa Rodríguez-Virgen, Sylvia Nashieli Marisela Sanabria-Alcaraz, Karina Jiménez-Duran, Kor Jent Van Dijk, Guadalupe Judith Marquez-Guzmá

    Aboriginal and Torres Strait Islander Suicide in Context

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    Aboriginal and Torres Strait Islander suicide has been an issue of national public health and mental health concern for only one decade, having increased dramatically from levels that were very low in the late 1980s to levels of young adult male suicide that are now substantially higher than for the non-indigenous population. In this review the authors socially and historically contextualize these changes, identifying the causal frameworks adopted in developing interventions, and present an explanation in narrative and pictorial form that draws on critical family-centered trauma

    Water Contamination Reduces the Tolerance of Coral Larvae to Thermal Stress

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    Coral reefs are highly susceptible to climate change, with elevated sea surface temperatures (SST) posing one of the main threats to coral survival. Successful recruitment of new colonies is important for the recovery of degraded reefs following mortality events. Coral larvae require relatively uncontaminated substratum on which to metamorphose into sessile polyps, and the increasing pollution of coastal waters therefore constitutes an additional threat to reef resilience. Here we develop and analyse a model of larval metamorphosis success for two common coral species to quantify the interactive effects of water pollution (copper contamination) and SST. We identify thresholds of temperature and pollution that prevent larval metamorphosis, and evaluate synergistic interactions between these stressors. Our analyses show that halving the concentration of Cu can protect corals from the negative effects of a 2–3°C increase in SST. These results demonstrate that effective mitigation of local impacts can reduce negative effects of global stressors
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