1,959 research outputs found
Families of Roles: A new theory of occurrent-dependent roles
PublishedRoles are important both theoretically and practically for modelling the world around us. Although many theories of roles have been proposed, there remain aspects which are little understood. In this paper we investigate roles and their contexts from a temporal point of view.We introduce the idea of a family of occurrent-dependent roles as a means to organise prospective and retrospective derived roles around an original role from which they are derived. By this means we account for the existence of groups of similar roles which are difficult to distinguish without a careful analysis of the temporal aspects. Following detailed informal discussion, we present a preliminary formalisation of the key concepts and relations.Air Force Research Laborator
Seasonal variations of stable carbon isotopic composition and biogenic tracer compounds of water-soluble organic aerosols in a deciduous forest
To investigate the seasonal changes in biogenic water-soluble organic carbon (WSOC) aerosols in a boreal forest, aerosol samples were collected continuously in the canopy of a deciduous forest in northern Japan during 2009–2010. Stable carbon isotopic composition of WSOC (&delta;<sup>13</sup>C<sub>WSOC</sub>) in total suspended particulate matter (TSP) exhibited a distinct seasonal cycle, with lower values from June through September (−25.5&plusmn;0.5 &permil;). This cycle follows the net CO<sub>2</sub> exchange between the forest ecosystem and the atmosphere, indicating that &delta;<sup>13</sup>C<sub>WSOC</sub> likely reflects the biological activity at the forest site. WSOC concentrations showed the highest values in early summer and autumn. Positive matrix factorization (PMF) analysis indicated that the factor in which biogenic secondary organic aerosols (BSOAs) dominated accounted for ~40 % of the highest concentrations of WSOC, where BSOAs mostly consisted of α-/β-pinene SOA. In addition, primary biological aerosol particles (PBAPs) made similar contributions (~57 %) to the WSOC near the forest floor in early summer. This finding indicates that the production of both primary and secondary WSOC aerosols is important during the growing season in a deciduous forest. The methanesulfonic acid (MSA) maximum was also found in early summer and had a distinct vertical gradient with larger concentrations near the forest floor. Together with the similar vertical gradients found for WSOC and &delta;<sup>13</sup>C<sub>WSOC</sub> as well as the α-/β-pinene SOA tracers, our results indicate that the forest floor, including ground vegetation and soil, acts as a significant source of WSOC in TSP within a forest canopy at the study site
Angle-resolved photoemission spectroscopy of Co-based boride superconductor LaCo1.73Fe0.27B2
We have performed angle-resolved photoemission spectroscopy of Co-based
boride superconductor LaCo1.73Fe0.27B2 (Tc = 4.1 K), which is isostructural to
the 122-type Fe-pnictide superconductor with the pnictogen atom being replaced
with boron. We found that the Fermi level is located at a dip in the density of
states (DOS) in contrast to Co-pnictide ferromagnets. This reduction in DOS
together with the strong Co 3d-B 2p covalent bonding removes the ferromagnetic
order and may cause the superconductivity. The energy bands near the Fermi
level show higher three dimensionality and a weaker electron-correlation effect
than those of Fe pnictides. The Fermi surface topology is considerably
different from that of Fe pnictides, suggesting the difference in the
superconducting mechanism between boride and pnictide superconductors.Comment: 5 pages, 4 figure
Genome scan of BTA1 for QTL affecting weaning weight, yearling weight and post-weaning growth in Japanese Black cattle
A genome scan for chromosomal regions of bovine chromosome one (BTA1) influencing weaning weight (WT6), yearling weight (WT12) and post-weaning average daily gain (PWADG) was performed using 112 half-sib progeny of 4 Japanese Black (Wagyu) sires and 98 microsatellite DNA markers. Identity-By-Descent (IBD) probabilities at specific chromosomal locations from multiple marker data were determined and a linear model containing the fixed effects of sex, parity and season of birth as well as age as a covariate, was fitted to the IBD coefficients and phenotypic data. Data were analysed by generating an F-statistic by the regression of phenotype on the IBD probabilities of inheriting an allele from the sire. Permutation tests at chromosome-wide significance thresholds were carried out over 1, 000 iterations at 1cM intervals while the boostrap with resampling procedure was followed to estimate confidence intervals and average QTL locations. All these procedures were implemented in the QTL Express Computer programme with a web-based user interface (available at: http://qtl.cap.ed.ac.uk/). A significant QTL (P chromosome-wise threshold = 0.05) for PWADG was identified in Sires 2 and 3 located at 27cM and 29cM (95% confidence intervals of the QTL locations being 0-132cM and 0-125cM) respectively. Another QTL for WT12 was identified at 113cM in Sire 2. No significant effect on WT6 was detected in any of the sires. Selection indices that include QTL with accurately estimated effects on carcass characteristics could reduce the amount of lengthy and costly data collection by providing a means of genetic evaluation early in the life cycle. Since PWADG is positively correlated with WT6 and WT12 in beef cattle, the identification of these QTL in Japanese Black Cattle holds a high prospect for the implementation of marker-assisted selection for the early attainment of slaughter weight in this breed
Microsatellite DNA marker mapping of bovine chromosome 1 for QTL affecting birth weight and preweaning growth in Japanese Black Cattle (Wagyu)
Interval mapping within 5 families of Japanese Black Cattle (Wagyu) to detect segregating QTL for birth weight and preweaning average daily gain on bovine chromosome 1 was performed by genotyping 132 half-sib progeny using 98 microsatellite DNA markers. A significant QTL for birth weight was detected at 114cM (95% confidence interval of 50-130.5cM) in one sire. Suggestive QTL for preweaning average daily gain were detected at 14cM and 18cM just below the chromosome-wide threshold in 2 sires. It was concluded that evidence of significant QTL in chromosomal regions of bovine chromosome one was compelling for birth weight hence enhancing the prospects of marker-assisted selection in this breed
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