8,305 research outputs found
Comparison of life history parameters for landed and discarded fish captured off the southeastern United States
Commercial fisheries that are managed with minimum size limits protect small fish of all ages and may affect size-selective mortality by the differential removal of fast growing fish. This differential removal may decrease the average size at age, maturation, or sexual transition of the exploited population. When fishery-independent data are
not available, a comparison of life history parameters of landed with those of discarded fish (by regulation) will
indicate if differential mortality is occurring with the capture of young but large fish (fast growing phenotypes).
Indications of this differential size-selective mortality would include the following: the discarded portion of the target fish would have similar age ranges but smaller sizes at age, maturation, and sexual transition as that of landed fish. We examined three species with minimum size limits but different exploitation histories. The known heavily exploited species (Rhomboplites aurorubens [vermilion snapper] and Pagrus pagrus [red porgy]) show signs of this
differential mortality. Their landed catch includes many young, large fish, whereas discarded fish had a similar age range and mean ages but smaller sizes at age than the landed
fish. The unknown exploited species, Mycteroperca phenax (scamp), showed no signs of differential mortality due
to size-selective fishing. Landed catch consisted of old, large fish and discarded scamp had little overlap in age ranges, had significantly different mean ages, and only small differences in size at age when compared to comparable
data for landed fish
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First CRDS-measurements of water vapour continuum in the 940nm absorption band
Measurements of near-infrared water vapour continuum using continuous wave cavity ring down spectroscopy (cw-
CRDS) have been performed at around 10611.6 and 10685:2 cm1. The continuum absorption coefficients for N2-
broadening have been determined for two temperatures and wavenumbers.
These results represent the first near-IR continuum laboratory data determined within the complex spectral environment in the 940nm water vapour band and are in reasonable agreement with simulations using the semiempirical CKD formulation
Reflector antennas with low sidelobes, low cross polarization, and high aperture efficiency
Techniques are presented for computing the horn near field patterns on the subreflectors and for correcting the phase center errors of the horn pattern by shaping the subreflector surface. The diffraction pattern computations for scanned beams are described. The effects of dish aperture diffraction on pattern bandwidth are investigated. A model antenna consisting of a reflector, shaped subreflector, and corrugated feed horn is described
Sclerostin does not play a major role in the pathogenesis of skeletal complications in type 2 diabetes mellitus
In contrast to previously reported elevations in serum sclerostin levels in diabetic patients, the present study shows that the impaired bone microarchitecture and cellular turnover associated with type 2 diabetes mellitus (T2DM)-like conditions in ZDF rats are not correlated with changes in serum and bone sclerostin expression. INTRODUCTION: T2DM is associated with impaired skeletal structure and a higher prevalence of bone fractures. Sclerostin, a negative regulator of bone formation, is elevated in serum of diabetic patients. We aimed to relate changes in bone architecture and cellular activities to sclerostin production in the Zucker diabetic fatty (ZDF) rat. METHODS: Bone density and architecture were measured by micro-CT and bone remodelling by histomorphometry in tibiae and femurs of 14-week-old male ZDF rats and lean Zucker controls (n = 6/group). RESULTS: ZDF rats showed lower trabecular bone mineral density and bone mass compared to controls, due to decreases in bone volume and thickness, along with impaired bone connectivity and cortical bone geometry. Bone remodelling was impaired in diabetic rats, demonstrated by decreased bone formation rate and increased percentage of tartrate-resistant acid phosphatase-positive osteoclastic surfaces. Serum sclerostin levels (ELISA) were higher in ZDF compared to lean rats at 9 weeks (+40 %, p < 0.01), but this difference disappeared as their glucose control deteriorated and by week 14, ZDF rats had lower sclerostin levels than control rats (-44 %, p < 0.0001). Bone sclerostin mRNA (qPCR) and protein (immunohistochemistry) were similar in ZDF, and lean rats at 14 weeks and genotype did not affect the number of empty osteocytic lacunae in cortical and trabecular bone. CONCLUSION: T2DM results in impaired skeletal architecture through altered remodelling pathways, but despite altered serum levels, it does not appear that sclerostin contributes to the deleterious effect of T2DM in rat bone
Análise da rentabilidade dos sistemas empresarial e familiar de produção de pêssego no sul do Rio Grande do Sul.
bitstream/item/31658/1/documento-86.pd
The Asymptotically Safe Standard Model: From quantum gravity to dynamical chiral symmetry breaking
We present a comprehensive non-perturbative study of the phase structure ofthe asymptotically safe Standard Model. The physics scales included range fromthe asymptotically safe trans-Planckian regime in the ultraviolet, theintermediate high-energy regime with electroweak symmetry breaking to stronglycorrelated QCD in the infrared. All flows are computed with a self-consistentfunctional renormalisation group approach, using a vertex expansion in thefluctuation fields. In particular, this approach takes care of all physicalthreshold effects and the respective decoupling of ultraviolet degrees offreedom. Standard Model and gravity couplings and masses are fixed by theirexperimental low energy values. Importantly, we accommodate for the differencebetween the top pole mass and its Euclidean analogue. Both, the correct massdetermination and the threshold effects have a significant impact on thequalitative properties, and in particular on the stability properties of thespecific ultraviolet-infrared trajectory with experimental Standard Modelphysics in the infrared. We show that in the present rather advancedapproximation the matter part of the asymptotically safe Standard Model has thesame number of relevant parameters as the Standard Model, and is asymptoticallyfree. This result is based on the novel UV fixed point found in the presentwork: the fixed point Higgs potential is flat but has two relevant directions.These results and their analysis are accompanied by a thorough discussion ofthe systematic error of the present truncation, also important for systematicimprovements.<br
Sistemas de producción de patata y otras hortalizas: procesos de producción, organización y consumo de productos ecológicos en Andalucía/España.
bitstream/item/43963/1/documento-329.pd
Change Mining in Adaptive Process Management Systems
The wide-spread adoption of process-aware information systems has resulted in a bulk of computerized information about real-world processes. This data can be utilized for process performance analysis as well as for process improvement. In this context process mining offers promising perspectives. So far, existing mining techniques have been applied to operational processes, i.e., knowledge is extracted from execution logs (process discovery), or execution logs are compared with some a-priori process model (conformance checking). However, execution logs only constitute one kind of data gathered during process enactment. In particular, adaptive processes provide additional information about process changes (e.g., ad-hoc changes of single process instances) which can be used to enable organizational learning. In this paper we present an approach for mining change logs in adaptive process management systems. The change process discovered through process mining provides an aggregated overview of all changes that happened so far. This, in turn, can serve as basis for all kinds of process improvement actions, e.g., it may trigger process redesign or better control mechanisms
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