438 research outputs found
Preparation of ordered poly /arylenesiloxane/ polymers
Preparation of ordered poly/arylenesiloxane/ polymer
Development of lubricating oils suitable for use with liquid oxidizers Final summary report, 4 Dec. 1969 - 4 Oct. 1970
Development of lubricating oils suitable for use with liquid oxidizer
Development of lubricating oils suitable for use with liquid oxidizers Quarterly progress report, 1 Jun. - 31 Aug. 1970
Investigating ester and alkyl compounds as lubricating oils for use with liquid oxidizer
Synthesis and evaluation of new high polymers for coating applications annual summary report no. 1, 26 jun. 1964 - 25 jun. 1965
Synthesis of organic and semi-organic polymers useful as high temperature coating materia
Development of lubricating oils suitable for use with liquid oxidizers Final summary report, 4 Mar. 1968 - 4 Mar. 1969
Lubricating properties and impact stability of polyfluoroalcohol derivatives at low temperatur
Synthesis and evaluation of new high temperature polymers for coating applications Technical summary report, 26 Jun. 1964 - 25 Sep. 1966
Synthesis, characterization, and evaluation of organic and semiorganic heat resistant polymer coating
Classical Correlation-Length Exponent in Non-Universal Quantum Phase Transition of Diluted Heisenberg Antiferromagnet
Critical behavior of the quantum phase transition of a site-diluted
Heisenberg antiferromagnet on a square lattice is investigated by means of the
quantum Monte Carlo simulation with the continuous-imaginary-time loop
algorithm. Although the staggered spin correlation function decays in a power
law with the exponent definitely depending on the spin size , the
correlation-length exponent is classical, i.e., . This implies that
the length scale characterizing the non-universal quantum phase transition is
nothing but the mean size of connected spin clusters.Comment: 4 pages, 3 figure
Interbular space characterization in adult capybara (Hydrochoerus hydrochaeris) testis
Social Waves in Giant Honeybees Repel Hornets
Giant honeybees (Apis dorsata) nest in the open and have evolved a plethora of defence behaviors. Against predatory wasps, including hornets, they display highly coordinated Mexican wave-like cascades termed ‘shimmering’. Shimmering starts at distinct spots on the nest surface and then spreads across the nest within a split second whereby hundreds of individual bees flip their abdomens upwards. However, so far it is not known whether prey and predator interact and if shimmering has anti-predatory significance. This article reports on the complex spatial and temporal patterns of interaction between Giant honeybee and hornet exemplified in 450 filmed episodes of two A. dorsata colonies and hornets (Vespa sp.). Detailed frame-by-frame analysis showed that shimmering elicits an avoidance response from the hornets showing a strong temporal correlation with the time course of shimmering. In turn, the strength and the rate of the bees' shimmering are modulated by the hornets' flight speed and proximity. The findings suggest that shimmering creates a ‘shelter zone’ of around 50 cm that prevents predatory wasps from foraging bees directly from the nest surface. Thus shimmering appears to be a key defence strategy that supports the Giant honeybees' open-nesting life-style
Seasonal Spatial Segregation in Blue Sharks (Prionace glauca) by Sex and Size Class in the Northeast Pacific Ocean
Aim: Animal tracking can provide unique insights into the ecology and conservation of marine species, such as the partitioning of habitat, including differences between life history stages or sexes, and can inform fisheries stock assessments, bycatch reduction and spatial management such as dynamic management.
Location: Northeast Pacific Ocean.
Methods: We used satellite tracking data from 47 blue sharks (Prionace glauca) from the Northeast Pacific to determine movements and home range along the west coast of North America, and sex–size class (immature females, mature males) specific habitat preferences using boosted regression trees. Using a suite of static and dynamic environmental variables, we determined distribution and habitat preferences across summer and fall for each sex–size class.
Results: We found that there was spatial segregation between sex–size classes particularly in the summer months with immature females found largely north of 33°N, and males south of 35°N. In fall, females travelled south, resulting in an overlap in distributions south of 37°N. Sea surface temperature (SST), latitude and longitude were top predictors. However, immature females and adult males demonstrated unique habitat preferences including SST, with immature females preferring cooler temperatures (SST \u3c 15°C) than adult males in summer, and a broader band of SST than adult males in fall. All models performed well, explaining 50%–67% of deviance, and 23%–41% of deviance when predictions were cross‐validated.
Main conclusions: We provide first insights into coastal movements and habitat preferences of blue sharks in the Northeast Pacific. We found that immature females undergo a seasonal southward migration in this more coastal habitat, similar to patterns observed in the North Atlantic. We also found some overlap between adult males and immature females in fall months, suggesting the importance of more coastal habitat in managing this species, particularly in determining population structure for blue shark stock assessments, and reducing blue shark bycatch
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