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991.
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Multiple ecological factors have been hypothesized to influence primate sleeping site selection. Testing multiple hypotheses about sleeping site selection permits examination of the relative strength of distinct ecological factors and expands our ability to understand how selection pressures influence primate sleeping behavior. Here we examine how avoidance of biting insects, thermoregulation, foraging efficiency, tree stability, and interspecific competition influence selection of sleeping sites by proboscis monkeys (Nasalis larvatus) in Indonesian Borneo. We collected data on relative insect abundance, temperature, rainfall, food availability, group size, sleeping site location, and presence of other primates for 12 mo. Using formal model comparison and information criteria, we analyzed the relative importance of these ecological factors in determining one aspect of sleeping site location: distance from the river. Our models supported the avoidance of biting insects and the foraging efficiency hypotheses. Proboscis monkeys slept further inland on nights when the abundance of sandflies was high along the river, and when less food was available along the river. Many studies suggest that primates select sleeping trees and locations to reduce predation risk; our study indicates that additional factors may also be important in determining sleeping site selection. 相似文献
993.
Dipendra Thapaliya Mark Dalman Jhalka Kadariya Katie Little Victoria Mansell Mohammed Y. Taha Dylan Grenier Tara C. Smith 《EcoHealth》2017,14(2):303-309
Staphylococcus aureus can colonize a range of species. Although numerous studies have isolated pathogenic bacteria from wild birds, very little is known regarding S. aureus and their potential to spread methicillin-resistant (MRSA) strains. The objective of this study was to determine the presence and molecular characteristics of S. aureus in geese fecal samples collected from ten state parks across Northeast Ohio (NEO). A total of 182 fecal samples from Canada geese (Branta canadensis) were collected in April 2015. Isolates were characterized using multi-locus sequence (MLST) and spa typing, as well as PCR to detect the presence of Panton–Valentine leukocidin (PVL), mecA, and scn genes. Antibiotic susceptibility testing was done via Vitek-2 system. The overall contamination by S. aureus in fecal samples was 7.1% (13/182); 7/182 (3.8%) were MRSA and 6/182 (3.3%) were methicillin-susceptible S. aureus (MSSA). One isolate was positive for PVL. A total of eight different spa types were observed. MLST included ST5, ST8, ST291, ST298, and ST2111. One (7.7%) MSSA isolate was multi-drug resistant. The S. aureus contamination in NEO state parks ranged from 0% (park 1, 4, 8, 9) to 35% (7/20) (park 5). Parks 2, 3, 6, and 7 had 5% (1/20) positive. The results of this study indicate that the feces of geese collected at various state parks in NEO may harbor S. aureus. 相似文献
994.
Hossein Mokhtarzadeh Chen Hua Yeow James Cho Hong Goh Denny Oetomo Katie Ewing 《Computer methods in biomechanics and biomedical engineering》2017,20(13):1382-1393
Background: Knee injuries are common during landing activities. Greater landing height increases peak ground reaction forces (GRFs) and loading at the knee joint. As major muscles to stabilize the knee joint, Quadriceps and Hamstring muscles provide internal forces to attenuate the excessive GRF. Despite the number of investigations on the importance of muscle function during landing, the role of landing height on these muscles forces using modeling during landing is not fully investigated. Methods: Participant-specific musculoskeletal models were developed using experimental motion analysis data consisting of anatomic joint motions and GRF from eight male participants performing double-leg drop landing from 30 and 60 cm. Muscle forces were calculated in OpenSim and their differences were analyzed at the instances of high risk during landing i.e. peak GRF for both heights. Results: The maximum knee flexion angle and moments were found significantly higher from a double-leg landing at 60 cm compared to 30 cm. The results showed elevated GRF, and mean muscle forces during landing. At peak GRF, only quadriceps showed significantly greater forces at 60 cm. Hamstring muscle forces did not significantly change at 60 cm compared to 30 cm. Conclusions: Quadriceps and hamstring muscle forces changed at different heights. Since hamstring forces were similar in both landing heights, this could lead to an imbalance between the antagonist muscles, potentially placing the knee at risk of injury if combined with small flexion angles that was not observed at peak GRF in our study. Thus, enhanced neuromuscular training programs strengthening the hamstrings may be required to address this imbalance. These findings may contribute to enhance neuromuscular training programs to prevent knee injuries during landing. 相似文献
995.
Nicholas A. Barber Katie A. Lamagdeleine-Dent Jason E. Willand Holly P. Jones Kenneth W. McCravy 《Biodiversity and Conservation》2017,26(14):3481-3498
Ecosystem restoration provides unique opportunities to study community dynamics under succession and can reveal how consumer communities re-assemble and respond to successional changes. Studying community dynamics from both taxonomic and functional trait perspectives also may provide more robust assessments of restoration progress or success and allow cross-system comparisons. We studied ground beetle (Coleoptera: Carabidae) communities for three years in a restored grassland chronosequence with sites from 0 to 28 years old. We measured traditional community metrics (abundance, richness, Shannon diversity) and functional trait metrics based on species’ body length, wing morphology, activity time, phenology, and diet. Communities had high species richness and abundance in early successional stages, but these declined in later stages to low levels comparable to an adjacent grassland remnant. Species composition also shifted with time, converging with the remnant. Although functional richness, like species richness, declined as succession progressed, functional divergence quickly increased and was maintained over time, suggesting niche differentiation in established communities. Young sites were typified by small, macropterous, phytophagous species, while older sites contained larger species more likely to be flightless and carnivorous. Prescribed burns also affected traits, decreasing prevalence of larger species. This study demonstrates that functionally diverse consumer communities can self-assemble under restoration practices. In a relatively short amount of time both morphological and trophic level diversity are established. However, prescribed fire intended to control non-desirable plants may also shape beetle community functional composition, and restoration managers should consider if plant community benefits of fire outweigh potential declines in consumer function. 相似文献
996.
997.
Use of Highly Specific Molecular Markers Reveals Positive Correlation between Abundances of Mesodinium cf. major and Its Preferred Prey,Teleaulax amphioxeia,During Red Water Blooms in the Columbia River Estuary 下载免费PDF全文
Lydie Herfort Katie Maxey Ian Voorhees Holly M. Simon Kolette Grobler Tawnya D. Peterson Peter Zuber 《The Journal of eukaryotic microbiology》2017,64(6):740-755
In a previous study, Teleaulax amphioxeia—the preferred prey of Mesodinium in the Columbia River estuary—were undetectable within intense annual blooms, suggesting blooms are prey‐limited or prey are acquired outside of bloom patches. We used a novel molecular approach specifically targeting the prey (i.e., Unique Sequence Element [USE] within the ribosomal RNA 28S D2 regions of T. amphioxeia nucleus and nucleomorph) in estuarine water samples acquired autonomously with an Environmental Sample Processor integrated within a monitoring network (ESP‐SATURN). This new approach allowed for both more specific detection of the prey and better constraint of sample variability. A positive correlation was observed between abundances of M. cf. major and T. amphioxeia during bloom periods. The correlation was stronger at depth (> 8.2 m) and weak or nonexistent in the surface, suggesting that predator–prey dynamics become uncoupled when stratification is strong. We confirmed exclusive selectivity for T. amphioxeia by M. cf. major and observed the incorporation of the prey nucleus into a 4‐nuclei complex, where it remained functionally active. The specific biomarker for T. amphioxeia was also recovered in M. cf. major samples from a Namibian coastal bloom, suggesting that a specific predator–prey relationship might be widespread between M. cf. major and T. amphioxeia. 相似文献
998.
Working rotating shifts may cause poorer sleep quality and, consequently, negatively affect visuospatial performance. However, studies linking sleep and visuospatial perception show conflicting results and are infrequent with regard to shift workers in their working environment. We evaluated the connection between sleep quality and visuospatial perception in 16 workers on rotating shifts from a petrochemical company (aged 29–53 years), using the Rey Complex Figure Test, the Sleep Diary, the Pittsburgh Sleep Quality Index (PSQI) and the Psychomotor Vigilance Test. The PSQI data indicated poor sleep quality. Two of the participants had low visuospatial performance, and reaction time was slower at the end of the night shift. Better sleep quality was associated with better visuospatial performance in the day shift (rho = 0.66, p < 0.05) and on days off. The results suggest that a good sleep quality may be associated with better visuospatial performance. 相似文献
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