990 resultados para Late antiquity Fonts escrites


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Children and adolescents mature at different rates such that individuals competing in the same competition may differ in physical and biological maturity despite being of similar chronological age. Whether or not differences translate into on-field performance in competition is relatively unknown. This study investigated the influence of biological maturity on fitness and match running performance in junior Australian football. Eighty-seven under-15 years players were categorised into early (n = 20), average (n = 45) and late (n = 22) maturity groups based on self-reported and anthropometric assessment of biological maturity. Running movements during competition were collected using GPS (5 Hz) technology. Early maturers were heavier and taller than all other boys (P < 0.05), while biological maturity was significantly correlated to 20 m sprint (r = 0.53, P < 0.01). Total distance, high-intensity (>14.4 km · h−1) running distance and number of high-intensity efforts were significantly greater (20.8%, 53.6%, 31.7%, respectively; P < 0.01) in early compared to late maturers. Number of sprints and peak speed in competition were not different. Pubertal development and maturity status partially explained the differences between players in physical size, functional running fitness and match running performance. Late maturing players in this Australian football under-15 age group were at a physical and performance disadvantage to their earlier maturing peers.

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The late-2000s global financial crisis has wrought dramatic impacts on the construction industry. However, the issue of whether the crisis influenced the behaviours of the construction industry has not been addressed yet. This research presents an econometric approach to investigating the effects of the recent global financial crisis on construction labour productivity. By employing the error correction model and panel regression methods, the direct and indirect effects of the financial crisis on the changes in Australian construction labour productivity are explored at national and state levels. Neither the direct nor the indirect effects appear statistically significant. The results indicate that the direct effect of the financial crisis drives up construction labour productivity at the national level, while the indirect effect diminishes productivity. The effects of the financial crisis on the state construction labour productivity vary from state to state. The financial crisis influenced construction labour productivity directly and significantly in the northern and eastern regions, while the direct effects appear not significant in the other states and territories. The indirect effects of the financial crisis on productivity are statistically significant in three regions: the Australian Capital Territory, the Northern Territory and Western Australia. By comparison, the model with the financial effects fails to provide more accurate simulating results. As such, this research concludes that the influence of the late-2000s financial crisis on Australian national and state construction labour productivity is limited.

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Analysis of Permian-Triassic brachiopod diversity and body size changes from different water depths spanning the continental shelf to basinal facies in South China provides insights into the process of environmental deterioration. Comparison of the temporal changes of brachiopod diversity between deepwater and shallow-water facies demonstrates that deepwater brachiopods disappeared earlier than shallow-water brachiopods. This indicates that high environmental stress commenced first in deepwater settings and later extended to shallow waters. This environmental stress is attributed to major volcanic eruptions, which first led to formation of a stratified ocean and a chemocline in the outer shelf and deeper water environments, causing the disappearance of deep marine benthos including brachiopods. The chemocline then rapidly migrated upward and extended to shallow waters, causing widespread mass extinction of shallow marine benthos. We predict that the spatial and temporal patterns of earlier onset of disappearance/extinction and ecological crisis in deeper water ecosystems will be recorded during other episodes of rapid global warming.

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BACKGROUND: Bipolar disorder (BD) is commonly comorbid with many medical disorders including atopy, and appears characterized by progressive social, neurobiological, and functional impairment associated with increasing number of episodes and illness duration. Early and late stages of BD may present different biological features and may therefore require different treatment strategies. Consequently, the aim of this study was to evaluate serum levels of eotaxin/CCL11, eotaxin-2/CCL24, IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, IFNγ, BDNF, TBARS, carbonyl, and GPx in a sample of euthymic patients with BD at early and late stages compared to controls. METHODS: Early-stage BD patients, 12 late-stage patients, and 25 controls matched for sex and age were selected. 10mL of peripheral blood was drawn from all subjects by venipuncture. Serum levels of BDNF, TBARS, carbonyl content, glutathione-peroxidase activity (GPx), cytokines (IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α and IFNγ), and chemokines (eotaxin/CCL11 and eotaxin-2/CCL24) were measured. RESULTS: There were no demographic differences between patients and controls. No significant differences were found for any of the biomarkers, except chemokine eotaxin/CCL11, whose serum levels were higher in late-stage patients with BD when compared to controls (p=0.022; Mann-Whitney U test). LIMITATIONS: Small number of subjects and use of medication may have influenced in our results. CONCLUSION: The present study suggests a link between biomarkers of atopy and eosinophil function and bipolar disorder. These findings are also in line with progressive biological changes partially mediated by inflammatory imbalance, a process referred to as neuroprogression.

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OBJECTIVES: People in the late stage of bipolar disorder (BD) experience elevated relapse rates and poorer quality of life (QoL) compared with those in the early stages. Existing psychological interventions also appear less effective in this group. To address this need, we developed a new online mindfulness-based intervention targeting quality of life (QoL) in late stage BD. Here, we report on an open pilot trial of ORBIT (online, recovery-focused, bipolar individual therapy). METHODS: Inclusion criteria were: self-reported primary diagnosis of BD, six or more episodes of BD, under the care of a medical practitioner, access to the internet, proficient in English, 18-65 years of age. Primary outcome was change (baseline - post-treatment) on the Brief QoL.BD (Michalak and Murray, 2010). Secondary outcomes were depression, anxiety, and stress measured on the DASS scales (Lovibond and Lovibond, 1993). RESULTS: Twenty-six people consented to participate (Age M=46.6 years, SD=12.9, and 75% female). Ten participants were lost to follow-up (38.5% attrition). Statistically significant improvement in QoL was found for the completers, t(15)=2.88, 95% CI:.89-5.98, p=.011, (Cohen׳s dz=.72, partial η(2)=.36), and the intent-to-treat sample t(25)=2.65, 95% CI:.47-3.76, (Cohen׳s dz=.52; partial η(2)=.22). A non-significant trend towards improvement was found on the DASS anxiety scale (p=.06) in both completer and intent-to-treat samples, but change on depression and stress did not approach significance. LIMITATIONS: This was an open trial with no comparison group, so measured improvements may not be due to specific elements of the intervention. Structured diagnostic assessments were not conducted, and interpretation of effectiveness was limited by substantial attrition. CONCLUSION: Online delivery of mindfulness-based psychological therapy for late stage BD appears feasible and effective, and ORBIT warrants full development. Modifications suggested by the pilot study include increasing the 3 weeks duration of the intervention, adding cautions about the impact of extended meditations, and addition of coaching support/monitoring to optimise engagement.

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New 87Sr/86Sr data based on 127 well-preserved and well-dated conodont samples from South China were measured using a new technique (LA-MC-ICPMS) based on single conodont albid crown analysis. These reveal a spectacular climb in seawater 87Sr/86Sr ratios during the Early Triassic that was the most rapid of the Phanerozoic. The rapid increase began in Bed 25 of the Meishan section (GSSP of the Permian-Triassic boundary, PTB), and coincided closely with the latest Permian extinction. Modeling results indicate that the accelerated rise of 87Sr/86Sr ratios can be ascribed to a rapid increase (>2.8×) of riverine flux of Sr caused by intensified weathering. This phenomenon could in turn be related to an intensification of warming-driven runoff and vegetation die-off. Continued rise of 87Sr/86Sr ratios in the Early Triassic indicates that continental weathering rates were enhanced >1.9 times compared to those of the Late Permian. Continental weathering rates began to decline in the middle-late Spathian, which may have played a role in the decrease of oceanic anoxia and recovery of marine benthos. The 87Sr/86Sr values decline gradually into the Middle Triassic to an equilibrium values around 1.2 times those of the Late Permian level, suggesting that vegetation coverage did not attain pre-extinction levels thereby allowing higher runoff.

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Abstract The brachiopod Superfamily Spiriferoidea diversified greatly and was widely distributed in the late Palaeozoic (Carboniferous–Permian), and yet its phylogeny has been seldom investigated with analytical methods. This is reflected in the current flux of very different classification schemes for this superfamily. This paper provides the first attempt to investigate the phylogenetic relationships of spiriferoid brachiopods through both cladistic and Bayesian analyses involving 24 discrete and continuous characters. The continuous characters, from morphometric data, have been separately discretized using the gap weighting method, and the ‘as such’ option in TNT. Our results highlight the potential significance of continuous characters in reconstructing and elucidating phylogenies, as much as qualitative characters. Building on the outcomes of the analyses, we also briefly evaluate existing classification schemes of Spiriferoidea. We found that none of the existing classifications fully reflect the phylogeny properly; major families within the superfamily, such as Spiriferidae, Choristitidae, and Trigonotretidae, turned out to be polyphyletic. Although this study is considered preliminary, due to the selection of and restriction to certain taxa, combined with the use of a relatively small number of characters, it nevertheless demonstrates that potentially the true phylogenetic relationships of spiriferoid taxa sharply contrast with any of the existing classification schemes. This highlights the need to develop an alternative scheme that takes into account a more comprehensive range of phylogenetic variables.