159 resultados para Dwelling Brachiopods


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Courtship displays are often important in determining male mating success but can also be costly. Thus, instead of courting females indiscriminately, males might be expected to adjust their signalling effort strategically. Theory, however, predicts that such adjustments should depend on the rate with which males encounter females, a prediction that has been subject to very little empirical testing. Here, we investigate the effects of female encounter rate on male courtship intensity by manipulating the time interval between sequential presentations of large (high quality) and small (low quality) females in a fish, the Australian desert goby Chlamydogobius eremius. Males that were presented with a small female immediately after a large female reduced their courtship intensity significantly. However, males courted large and small females with equal intensity if the interval between the sequential presentations was longer. Our results suggest that mate encounter rate is an important factor shaping male reproductive decisions and, consequently, the evolutionary potential of sexual selection.

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The uppermost 5-15 m of the Douling Formation in the southern Hunan area. South China, yields a diverse fauna comprised of ammonoids, bivalves, and brachiopods. The brachiopods reported in this paper consist of 51 species in 34 genera and are dominated by the Lopingian (Late Permian) species associated with a few species persisting from the underlying Maokouan (Late Guadalupian). This fauna is of earliest Wuchiapingian in age as precisely constrained by the associated conodont Clarkina postbitteri postbitteri and the Guadalupian-type ammonoid fauna of the Roadoceras-Doulingoceras Zone in the brachiopod horizon. The discovery of the Lopingian species-dominated brachiopod fauna in the earliest Wuchiapingian in southern Hunan suggests a much less pronounced effect of the pre-Lopingian crisis (end-Guadalupian mass extinction) than the end-Changhsingian mass extinction in terms of brachiopods, a contemporaneous onset of the Lopingian recovery/radiation during the pre-Lopingian crisis period, and taxonomic selectivity of the pre-Lopingian crisis in terms of different fossil groups. New taxa are Echinauris doulingensis n. sp., Pararigbyella quadrilobata n. gen. and n. sp. and P. doulingensis n. gen. and n. sp.

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Objective Recent evidence suggests a role for diet quality in the common mental disorders depression and anxiety. We aimed to investigate the association between diet quality, dietary patterns, and the common mental disorders in Norwegian adults.

Methods
This cross-sectional study included 5731 population-based men and women aged 46 to 49 and 70 to 74 years. Habitual diet was assessed using a validated food frequency questionnaire, and mental health was measured using the Hospital Anxiety and Depression Scale.

Results After adjustments for variables including age, education, income, physical activity, smoking, and alcohol consumption, an a priori healthy diet quality score was inversely related to depression (odds ratio [OR] = 0.71, 95% confidence interval [CI] = 0.59–0.84) and anxiety (OR = 0.77, 95% CI = 0.68–0.87) in women and to depression (OR = 0.83, 95% CI = 0.70–0.99) in men. Women scoring higher on a healthy dietary pattern were less likely to be depressed (OR = 0.68, 95% CI = 0.57–0.82) or anxious (OR = 0.87, 95% CI = 0.77–0.98), whereas men were more likely to be anxious (OR = 1.19, 95% CI = 1.03–1.38). A traditional Norwegian dietary pattern was also associated with reduced depression in women (OR = 0.77, 95% CI = 0.64–0.92) and anxiety in men (OR = 0.77, 95% CI = 0.61–0.96). A western-type diet was associated with increased anxiety in men (OR = 1.27, 95% CI = 1.14–1.42) and women (OR = 1.29, 95% CI = 1.17–1.43) before final adjustment for energy intake.

Conclusions
In this study, those with better quality diets were less likely to be depressed, whereas a higher intake of processed and unhealthy foods was associated with increased anxiety.

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Four Ambocoeliidae brachiopod species including one new species (Crurithyris tazawai sp. nov., Crurithyris sp., Paracrurithyris pygmaea and Attenuatella mengi) are described from the Changhsingian (Late Permian) deep-water facies of South China. Analysis of the morphology, palaeoecology and palaeogeographical and temporal distributions of these species revealed that the presence of a delthyrium and/or the micro-ornaments among three of the four species (Crurithyris tazawai sp. nov., Paracrurithyris pygmaea and Attenuatella mengi) favoured an epifaunal (epiphytic) lifestyle. Morphological differences suggest that Paracrurithyris pygmaea may have been more effective metabolically in forming the shell compared with Attenuatella mengi and Crurithyris tazawai. The temporal and palaeogeographical distribution of Attenuatella suggests that A. mengi inhabited cool or cold deep waters. Both Crurithyris tazawai and Attenuatella mengi disappeared earlier in the stratigraphic record than Paracrurithyis pygmaea during the Permian–Triassic mass extinction. These differences in timing of extinction, morphology and palaeogeographical distributions suggest that oxygen deficiency and trophic resource limitation (a consequence of the changing composition of marine phytoplankton in the seas) may have contributed to the end-Permian mass extinction.

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Discourses of research leadership define not only what quality research leadership can and should be, but also identify those who speak and act with authority. Similarly, these discourses construct particular professional identities and idealised ‘ways of being’. They provide possibilities for research leaders as well as those categorised as 'Early Career Researchers' (ECRs) to create alternative identities and representations of themselves. This study reports the views of 32 academics across 16 Australian universities in four States about research mentoring and leadership for ECRs. The primary interest was to explore how research leadership is conceptualised, implemented and negotiated in the disciplinary fields of business, nursing and education. Whilst a number of ECRs viewed formal research mentoring as taking a ‘tick the box’ approach that they believed of limited value, a number of research leaders had different views. Most senior research leaders viewed the systemic provision of assistance their universities offered in a positive light. The dissonance in views centred on the subject positioning of academics in research. The dissatisfaction expressed by ECRs, a number of whom positioned themselves as fringe-dwellers ‘on the edge’ of their institutional research culture, raises questions about research sustainability and succession planning in Australian tertiary
institutions.

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This research discussed various topics related to Late Palaeozoic spiriferid brachiopod fossils. The outcomes include taxonomic and biostratigraphic revision of Permian brachiopods from Spitsbergen, palaeogeographical/palaeoenvironmental reconstruction of northern margin of Pangea during the Permian, interpretation of phylogeny among spiriferoidean brachiopods, and analysis of brachiopod shell morphology through new three-dimensional techniques.

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