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61.
The next generation of climate-driven, disease prediction models will most likely require a mechanistically based, dynamical framework that parameterizes key processes at a variety of locations. Over the next two decades, consensus climate predictions make it possible to produce forecasts for a number of important infectious diseases that are largely independent of the uncertainty of longer-term emissions scenarios. In particular, the role of climate in the modulation of seasonal disease transmission needs to be unravelled from the complex dynamics resulting from the interaction of transmission with herd immunity and intervention measures that depend upon previous burdens of infection. Progress is also needed to solve the mismatch between climate projections and disease projections at the scale of public health interventions. In the time horizon of seasons to years, early warning systems should benefit from current developments on multi-model ensemble climate prediction systems, particularly in areas where high skill levels of climate models coincide with regions where large epidemics take place. A better understanding of the role of climate extremes on infectious diseases is urgently needed.  相似文献   
62.
Sediment grain size and organic carbon (OC) data collected over the past 50 years, together with δ13C values of OC in recently collected samples, were analyzed to improve understanding of sediment OC distribution and abundance in Todos Santos Bay. Sediments in the submarine canyon at the mouth of the bay and in quiet-water locations along the shore are fine grained, high in OC, and have generally low δ13C values; sediments in high-energy environments are low in OC and have high δ13C values. A bivariate isotopic mixing model indicates that none of the sediments contain >50% terrigenous OC (average ~30%), and that the terrigenous OC content of the sediments is a small proportion of the OC content of local soils. Sediment OC composition is apparently controlled by energy-related sorting and deposition, oxidation of much of the original terrigenous OC, and replacement of some terrigenous OC by marine OC.  相似文献   
63.
Subaqueous sand dunes are common bedforms on continental shelves dominated by tidal and geostrophic currents. However, much less is known about sand dunes in deep‐marine settings that are affected by strong bottom currents. In this study, dune fields were identified on drowned isolated carbonate platforms in the Mozambique Channel (south‐west Indian Ocean). The acquired data include multibeam bathymetry, multi‐channel high‐resolution seismic reflection data, sea floor imagery, a sediment sample and current measurements from a moored current meter and hull‐mounted acoustic Doppler current profiler. The dunes are located at water depths ranging from 200 to 600 m on the slope terraces of a modern atoll (Bassas da India Atoll) and within small depressions formed during tectonic deformation of drowned carbonate platforms (Sakalaves Seamount and Jaguar Bank). Dunes are composed of bioclastic medium size sand, and are large to very large, with wavelengths of 40 to 350 m and heights of 0·9 to 9·0 m. Dune migration seems to be unidirectional in each dune field, suggesting a continuous import and export of bioclastic sand, with little sand being recycled. Oceanic currents are very intense in the Mozambique Channel and may be able to erode submerged carbonates, generating carbonate sand at great depths. A mooring located at 463 m water depth on the Hall Bank (30 km west of the Jaguar Bank) showed vigorous bottom currents, with mean speeds of 14 cm sec?1 and maximum speeds of 57 cm sec?1, compatible with sand dune formation. The intensity of currents is highly variable and is related to tidal processes (high‐frequency variability) and to anticyclonic eddies near the seamounts (low‐frequency variability). This study contributes to a better understanding of the formation of dunes in deep‐marine settings and provides valuable information about carbonate preservation after drowning, and the impact of bottom currents on sediment distribution and sea floor morphology.  相似文献   
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65.
In the current world, it is easy to listen that everybody and everything is connected. Over this connected world, the concept of location-based services has grown in order to provide digital services in everyplace and at every time. Nevertheless, this is not 100% true because the connection is not guaranteed for many people and in many places. These are the Degraded Communications Environments (DCE), environments where the availability of high-speed communications is not guaranteed in at least the 75% of the time. This paper works over the experience of a previous work in developing light protocols that do not need broadband for communication. This work provides an extension of these protocols for the inclusion of mobile devices as elements of the communication process and a set of libraries to allow the development of applications in DCE. The work done has involved the development of two frameworks: an Android framework that makes the incorporation of Android devices easier and a server-based framework that provides the server side for the development of the referred applications. A use case that uses these two frameworks has been developed. Finally, all technology developed is available throw a public Git repository.  相似文献   
66.
Foraging behavior and diet of breeding seabirds may be analysed simultaneously with the combined use of remote sensing devices and stable isotope analysis. Imperial shag, Phalacrocorax atriceps, breeding at Punta León colony, Argentina, were equipped with global positioning system (GPS) loggers to record foraging trips and blood samples were taken after removal of the devices in order to analyse their nitrogen and carbon stable isotope composition in whole blood and plasma. Whole blood was correlated to plasma isotopic composition for each individual (n = 35), linking diet in the short and medium term. Sexes did not differ in isotopic signatures. The maximum distance reached and the total number of dives that individuals made on two consecutive foraging trips were correlated to their plasma nitrogen isotopic signature. Individuals that went further from the colony and dived fewer times presented more positive signatures, indicative of benthic prey consumption (e.g. Raneya brasiliensis). Diet was predominantly benthic with some individuals incorporating pelagic prey (Engraulis anchoita) and even cephalopods (Octopus tehuelchus). Within breeding pairs (n = 9), different combinations of foraging and prey preferences were observed. Estimated trophic levels of these individuals were similar to those of the same species in other colonies further south along the Patagonian coast.  相似文献   
67.
Theoretical and Applied Climatology - Heat wave (HW) events are becoming more frequent, and they have important consequences because of the negative effects they can have not only on the human...  相似文献   
68.
Three-dimensional modelling from single images remains an interesting topic of investigation in the research community, even though range sensors are becoming a common alternative for the generation of 3D information. The interest in single-image-based modelling is motivated by a wide spectrum of applications such as cultural heritage, civil engineering, urban planning and even criminology. In this paper a complete new production flowline is presented for modelling based on a single image. The modelling process consists of a series of familiar steps in photogrammetry and computer vision: feature extraction, vanishing point computation, camera self-calibration, 3D reconstruction and dimensional analysis. In particular, the methodology developed for single-image-based modelling takes a scientific approach combining several proven techniques with robust estimators. Finally, in order to demonstrate its capabilities, the reported examples include several real situations applied in different contexts.  相似文献   
69.
Abstract Dating of zircon cores and rims from granulites developed in a shear zone provides insights into the complex relationship between magmatism and metamorphism in the deep roots of arc environments. The granulites belong to the uppermost allochthonous terrane of the NW Iberian Massif, which forms part of a Cambro‐Ordovician magmatic arc developed in the peri‐Gondwanan realm. The obtained zircon ages confirm that voluminous calc‐alkaline magmatism peaked around 500 Ma and was shortly followed by granulite facies metamorphism accompanied by deformation at c. 480 Ma, giving a time framework for crustal heating, regional metamorphism, deformation and partial melting, the main processes that control the tectonothermal evolution of arc systems. Traces of this arc can be discontinuously followed in different massifs throughout the European Variscan Belt, and we propose that the uppermost allochthonous units of the NW Iberian Massif, together with the related terranes in Europe, constitute an independent and coherent terrane that drifted away from northern Gondwana prior to the Variscan collisional orogenesis.  相似文献   
70.
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