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41.
A Neogene turtle from Brasil is described. It represents the first find of a new species close to the extant Podocnemis sextuberculata. Both species constitute a new clade in the genus. The synapomorphies they share and the differences between them are given. P. negrii nov. sp. is the second fossil species of the genus, after P. bassleri from the Neogene of Peru, which constitutes another clade with the extant P. expansa. The relationships between these two clades and the other species of the genus are not determinate.  相似文献   
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France  R. L. 《Hydrobiologia》2000,441(1):237-240
Beaver are well known to influence the geomorphology and geochemistry of boreal waters, in addition to being prominent vectors in the selective import of deciduous coarse woody debris (CWD). Because the stable carbon isotope ratios of deciduous trees are lower than those of coniferous trees, the possibility exists that the 13C values of particulate organic matter near beaver lodges may differ from those characteristic for littoral regions without beaver activity. In agreement with this supposition, 13C was found to significantly increase in progressively smaller size fractions of CWD collected from near lodges, probably due to the more rapid breakdown, decomposition and disappearance of deciduous material.  相似文献   
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An analysis of the compartmental scheme used to determine the rate and extent of ruminal degradation of feeds is presented. Attention is given to the kinetic representation of the degradation of the potentially degradable fraction. Changing the kinetic order of the rate, and introducing indigestible substrate inhibition and microbial activity into its representation, are investigated. This leads to response functions such as the Gompertz and logistic for describing the cumulative disappearance of potentially degradable substrate during in-sacco and in-vitro incubation.  相似文献   
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By shedding light on variation in time as well as in space, long-term biogeographic studies can help us define organisms’ distribution patterns and understand their underlying drivers. Here we examine distributions of Pseudomonas in and around 15 human homes, focusing on the P. putida and P. fluorescens species groups. We describe recovery from 10,941 samples collected during up to 8 visits per home, occurring on average 2.6 times per year. We collected a mean of 141 samples per visit, from sites in most rooms of the house, from the surrounding yards, and from human and pet occupants. We recovered Pseudomonas in 9.7% of samples, with the majority of isolates being from the P. putida and P. fluorescens species groups (approximately 62% and 23% of Pseudomonas samples recovered respectively). Although representatives of both groups were recovered from every season, every house, and every type of environment sampled, recovery was highly variable across houses and samplings. Whereas recovery of P. putida group was higher in summer and fall than in winter and spring, P. fluorescens group isolates were most often recovered in spring. P. putida group recovery from soils was substantially higher than its recovery from all other environment types, while higher P. fluorescens group recovery from soils than from other sites was much less pronounced. Both species groups were recovered from skin and upper respiratory tract samples from healthy humans and pets, although this occurred infrequently. This study indicates that even species that are able to survive under a broad range of conditions can be rare and variable in their distributions in space and in time. For such groups, determining patterns and causes of stochastic and seasonal variability may be more important for understanding the processes driving their biogeography than the identity of the types of environments in which they can be found.  相似文献   
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Background

Mindfulness is defined as non-judgmental awareness of the present moment. There is some evidence of the efficacy of mindfulness-based interventions in weight loss. However, this psychological concept has only been rarely explored in observational studies, and no study to date has examined the association between dispositional mindfulness and weight status in a large population-based sample.

Objective

We aimed to examine the relationship between mindfulness scores and weight status in a large sample of the adult general population in France.

Design and Methods

A total of 14,400 men and 49,228 women aged ≥18 y participating in the NutriNet-Santé study were included in this cross-sectional analysis. We collected mindfulness data using the Five Facet Mindfulness Questionnaire as well as self-reported weight and height. The association between weight status and dispositional mindfulness, as well as its subscales (observing, describing, acting with awareness, non-judging and non-reactivity), was assessed using multinomial logistic regression models adjusted for socio-demographic and lifestyle factors.

Results

Women with higher dispositional mindfulness scores were less likely to be overweight (excluding obesity) (OR quartile 4 vs. 1 = 0.84, 95% CI: 0.79-0.90) and obese (OR quartile 4 vs. 1 = 0.71, 95% CI: 0.65-0.78). In addition, overall, in this group, all subscales were inversely associated with weight status, with the strongest association found for the “observing” subscale. In men, higher mindfulness was associated only with lower odds of obesity (OR quartile 4 vs. 1 = 0.81 (0.69, 0.96)), and only the “observing” and “non-reactivity” subscales were significantly inversely associated with weight status.

Conclusion

Results support the interest of a shift in perspective that takes into account positive psychological and cognitive factors such as dispositional mindfulness in the investigation of obesity and its associated factors.  相似文献   
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The continental margin off the northeastern United States (NEUS) contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV) dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa), demersal fish (69 taxa), and decapod crustacean (34 taxa) assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichos and the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While initial exploration revealed the NEUS region to be both geologically dynamic and biologically diverse, further research into the abiotic conditions and the biotic interactions that influence species abundance and distribution is needed.  相似文献   
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