940 resultados para Bellingshausen Sea, till sheet on N side of Ronne Entrance Trough
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Deterrence-based initiatives form a cornerstone of many road safety countermeasures. This approach is informed by Classical Deterrence Theory, which proposes that individuals will be deterred from committing offences if they fear the perceived consequences of the act, especially the perceived certainty, severity and swiftness of sanctions. While deterrence-based countermeasures have proven effective in reducing a range of illegal driving behaviours known to cause crashes such as speeding and drink driving, the exact level of exposure, and how the process works, remains unknown. As a result the current study involved a systematic review of the literature to identify theoretical advancements within deterrence theory that has informed evidence-based practice. Studies that reported on perceptual deterrence between 1950 and June 2015 were searched in electronic databases including PsychINFO and ScienceDirect, both within road safety and non-road safety fields. This review indicated that scientific efforts to understand deterrence processes for road safety were most intense during the 1970s and 1980s. This era produced competing theories that postulated both legal and non-legal factors can influence offending behaviours. Since this time, little theoretical progression has been made in the road safety arena, apart from Stafford and Warr's (1993) reconceptualisation of deterrence that illuminated the important issue of punishment avoidance. In contrast, the broader field of criminology has continued to advance theoretical knowledge by investigating a range of individual difference-based factors proposed to influence deterrent processes, including: moral inhibition, social bonding, self-control, tendencies to discount the future, etc. However, this scientific knowledge has not been directed towards identifying how to best utilise deterrence mechanisms to improve road safety. This paper will highlight the implications of this lack of progression and provide direction for future research.
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The in-situ study of steel corrosion in sea bottom sediment (SBS) was carried out by Transplanting Burying Plate method (TBP method). It was found that the corrosion rate of steel in the sea bottom sediment with sulfate reducing bacteria (SRB) could be as high as ten times of that in sea bottom sediment without SRB. The experiments in simulated sea bottom sediments with different SRB contents by artificial culturing showed that the electrochemical behavior of steel in the sea bottom sediment with SRB was different from that without SRB. SRB altered the polarization behavior of steel significantly. The environment was acidified due to the activity of SRB and the corrosion of steel was accelerated. The corrosion of carbon steel in sea bottom sediment is anaerobic corrosion, and the main factor is anaerobe. There are SRB commonly in SBS, and the amount of SRB decreases along with the depth of sediment. Because of the asymmetry and variation of sea bottom sediment, the most dangerous corrosion breakage of steel in SBS is local corrosion caused by SRB. So the main countermeasure of corrosion protection of sea bottom steel facilities should be controlling of the corrosion caused by anaerobe.
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Physical fractions (free light fraction, intra-aggregate light fraction and heavy fraction) of soil organic matter (SOM) are good indicators of soil quality for sustainable land use. The objective of this study was to evaluate the effect of cover crops on total organic carbon (TOC) and physical fractions of soil organic matter in soil under a no-tillage system (NTS) and a conventional tillage system (CTS, one plowing and two disking). A three-year field experiment was carried out as a cover crop-rice (Oryza sativa)-cover crop-rice rotation. Treatments included cover crops (Panicum maximum, Brachiaria ruziziensis, Brachiaria brizantha, and pearl millet (Pennisetum glaucum), fallow, till or no till. The SOM was physically fractionated in free light fraction (FLF), intra-aggregates light fraction (IALF) and heavy fraction (HF). The levels of C in whole soil were also evaluated, as well as C in the light fractions (FLF+IALF) and in the HF. Results indicated that concentrations of C in the FLF and IALF in surface soils (0-0.05m) were much higher (10.8 and 1.95gkg-1, respectively) than that in the 0.05-0.1m soil depth (7.68 and 1.54gkg-1, respectively) and in the 0.1-0.2m soil depth (4.98 and 1.24gkg-1, respectively). The NTS resulted in higher levels of FLF (12.2gkg-1) and IALF (2.19gkg-1) than with CTS (1.37-7.30gkg-1). Millet had the highest C (19.5gkg-1) and N (1.1gkg-1) concentrations in soil. There was an accumulation of TOC and total N in the surface soil with cover crops, and concentrations of TOC were higher in the HF (79.0%) than in the light fractions (21.0%). Although SOM changed little during the two years of this experiment, the various C fractions were significantly affected by the tillage treatments. We conclude that SOM physical fractionation allowed seeing significant differences caused by the soil management in the organic matter dynamics in a short period of time. © 2013 Elsevier B.V.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The present thesis analyses the effects of the enrichment of the soil with fertilizer and sea level rise (SLR) on salt marsh vegetation. We simulated different conditions of the salt marshes under current and projected sea level rise. These habitats are colonised by various types of plants, we focused on species belonging to the genus Spartina. This plant seems to be particularly sensitive to eutrophication due to human activities, as experiments have documented a loss of habitat associated with altered nutrient conditions. We manipulated experimentally the types of sediment, the concentration of nutrients and sea level rise. We wanted to test whether eutrophication can affect the aboveground/belowground growth of the vegetation, and indirectly the erosion of the sediment, with potentially interacting effects with soil type and SLR in affecting the loss of the habitats and species. The study lasted from July to October. The data were analysed using Permanova. The results showed that the plants were placed in growth spiked sediment different from those raised in the untreated sediment. Furthermore, the sediment underwent a level of erosion differently depending on the growth of plants and the condition they were in the pots, current or future sea levers. These results suggest that the total salt marsh habitat is very sensitive to changes caused by human activities, and that excessive eutrophication, combined with SLR will likely facilitate further loss of salt marsh vegetation.
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To test whether in-the-canal (ITC) microphones have an impact on spatial discrimination and speech perception by taking advantage of auricular cues.
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The morbilliviruses measles virus (MeV) and canine distemper virus (CDV) both rely on two surface glycoproteins, the attachment (H) and fusion proteins, to promote fusion activity for viral cell entry. Growing evidence suggests that morbilliviruses infect multiple cell types by binding to distinct host cell surface receptors. Currently, the only known in vivo receptor used by morbilliviruses is CD150/SLAM, a molecule expressed in certain immune cells. Here we investigated the usage of multiple receptors by the highly virulent and demyelinating CDV strain A75/17. We based our study on the assumption that CDV-H may interact with receptors similar to those for MeV, and we conducted systematic alanine-scanning mutagenesis on CDV-H throughout one side of the beta-propeller documented in MeV-H to contain multiple receptor-binding sites. Functional and biochemical assays performed with SLAM-expressing cells and primary canine epithelial keratinocytes identified 11 residues mutation of which selectively abrogated fusion in keratinocytes. Among these, four were identical to amino acids identified in MeV-H as residues contacting a putative receptor expressed in polarized epithelial cells. Strikingly, when mapped on a CDV-H structural model, all residues clustered in or around a recessed groove located on one side of CDV-H. In contrast, reported CDV-H mutants with SLAM-dependent fusion deficiencies were characterized by additional impairments to the promotion of fusion in keratinocytes. Furthermore, upon transfer of residues that selectively impaired fusion induction in keratinocytes into the CDV-H of the vaccine strain, fusion remained largely unaltered. Taken together, our results suggest that a restricted region on one side of CDV-H contains distinct and overlapping sites that control functional interaction with multiple receptors.
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We reconstructed the surface hydrography of the South Equatorial Current in the western Indian Ocean for the last 65,000 years using a marine sediment core record. Results show that tropical Indian Ocean temperatures resemble temperatures from Antarctic ice cores with warm and cold fluctuations synchronous with the Antarctic Cold Reversal and the Antarctic warm events A1-A4. The most likely thermal link involves Subantarctic Mode Water (SAMW) which forms north of the subpolar frontal zone and spreads northward into the Indian Ocean. This subsurface water mass is the prime suspect because of a stronger temperature response in the thermocline (recorded by the foraminifer N. dutertrei) than in surface water (G. ruber).
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Red, black ink on tracing paper; topo. lines; unsigned; 75 x 37 cm.; Scale: 1" = 20' [from photographic copy by Lance Burgharrdt]