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981.
On December 1, 2000, new legislation came into force in Victoria, Australia, that involved a framework for the procedure to be followed by the police for the detection of drivers impaired by drugs other than alcohol. An integral part of the procedure is the use of performance tests known as the standardized field sobriety tests (SFSTs) and the analysis of blood samples for the presence of drugs other than alcohol. This paper outlines the new legislative framework and the drug impairment detection procedures currently in place in Victoria. This paper also evaluates the data collected using the framework for the first five years since implementation in Victoria.  相似文献   
982.
Numerous studies have focussed on the relationship between female choice and the multiple exaggerated sexual traits of males. However, little is known about the ability of males to actively enhance specific components of their display in response to the loss of one component. We investigated the capacity of male satin bowerbirds (Ptilonorhynchus violaceus) to respond to the loss of one of their sexual signals by performing an experiment in which we removed decorations at their bowers. We found that males compensated for decoration loss by increasing bower construction behaviour and decreasing their latency to bower painting. These results are novel because they suggest that males can assess the quality of their own display and make decisions about how to augment their displays. We discuss these results in the context of previous studies of mate choice in satin bowerbirds, as both of the supplementary behaviours we observed are known correlates of male mating success.  相似文献   
983.
PURPOSE: Vehicle and occupant responses in rollovers are complex since many factors influence both. This study analyzes the following factors: 1) belt use, 2) seated position with respect to the lead side in the rollover, 3) another front occupant in the crash, and 4) number of quarter rolls. The aim was to improve our understanding of rollover injury mechanisms. METHOD: Rollover accidents were analyzed using 1992-2004 NASS-CDS data. The sample included adult drivers and right-front passengers. All occupants were evaluated and then a subset of non-ejected occupants was analyzed. Using roll direction and seating position, the sample was divided into near- and far-seated occupants. Injury and fatality risks were determined by seatbelt use, occupancy, rollover direction, and number of quarter rolls. Risk was defined as the number of injured (e.g., MAIS 3+) divided by the number of exposed occupants (MAIS 0-6). Significance in differences was determined. A matched-pair analysis was used to determine the risk of serious injury for near- and far-seated occupants who were either belted or unbelted in the same crash. RESULTS: For all occupants, serious injury risks were highest for far-seated, unbelted occupants at 18.1% +/- 4.8%, followed by near-seated unbelted occupants at 12.0% +/- 3.5%. However, the difference was not statistically significant. Belted near- and far-seated occupants had a similar injury risk of 4.3% +/- 1.2% and 4.0% +/- 1.2%, respectively. For non-ejected occupants, serious injury risk was 9.5% +/- 3.2% for far-seated unbelted occupants and 4.9% +/- 2.1% for near-seated unbelted occupants, not a statistically significant difference. Serious injury risk was similar for belted near- and far-seated non-ejected occupants, at 3.6% +/- 1.1%. Seatbelts were 64.2%-77.9% effective in preventing serious injury for all occupants and 62.1%-26.5% for far- and near-seated, non-ejected occupants, respectively. Based on the matched pairs, seatbelts were less effective for near-seated (5.0%) compared to far-seated (2.8%) occupant MAIS 3+F risks. This was similar for non-ejected occupants. An unbelted near-seated occupant increased the risk for a belted far-seated occupant by 2.2 times, whereas an unbelted far-seated occupant increased the risk for a belted near-seated occupant by 10.2 times. For all occupants, the risk of serious injury increased with the number of quarter rolls, irrespective of seated position. For near-seated occupants, seatbelt effectiveness was higher in < or =1 roll than 1+ roll, at 72.3% compared to 28.3%. For far-seated occupants, seatbelt effectiveness was similar in < or =1 and 1+ roll samples at 78.3% and 76.8%, respectively. Near-seated occupants had the lowest serious injury risk when they were the sole occupant in the vehicle. This was also true for non-ejected occupants. However, far-seated occupants had a lower injury risk when another occupant was involved in the crash. CONCLUSIONS: The effect of carrying another occupant appears to reduce the risk of serious injury to far-seated occupants. However, near-seated occupants are better off being the sole occupant in the vehicle. Seatbelt effectiveness was lowest at 28.3% for non-ejected, near-seated occupants in 1+ rolls. This finding deserves further evaluation in an effort to improve seatbelt effectiveness in rollovers. For belted drivers alone in a rollover, fatality risks are 2.24 times higher for the far- versus near-seated position. Analysis of rollovers by quarter turns indicates that occupants are both far-side and near-side in rollovers. The extent to which this confounds the relationship between roll direction, seating position, and injury risk is unknown.  相似文献   
984.
研究限氧EGSB反应器内颗粒污泥的沉淀性能、产甲烷活性、形态、抗温度和负荷冲击等特性,以分析限氧EGSB反应器长期高效稳定运行的可行性.结果表明,限氧运行使得颗粒污泥的沉速降低,但仍能保持20.07~51.86 m/h的高沉速,保证了限氧EGSB反应器内约42 g/L的高污泥浓度;加入适量氧并没有对甲烷菌产生毒害作用,反而有所提高,提高幅度为11.94%.限氧EGSB反应器内颗粒污泥表面和内部微生物没有出现明显的分区分布,中高进水浓度时没有出现甲烷八叠球菌的明显优势;限氧EGSB反应器内颗粒污泥在经历温度和COD负荷双重冲击后,COD去除率明显降低,出水VFA明显增高,产气量明显降低,甚至出现不产气的情况.COD去除率的恢复很快,仅需20 d;出水VFA和产气也逐渐恢复,但有所滞后;微生物的恢复要慢些,扫描电镜结果表明,有些颗粒污泥表面的微生物细胞仍存在收缩现象.  相似文献   
985.
Graduated driver licensing (GDL) is a concept for how to transform non-drivers into reasonably safe drivers while minimizing the risks as they learn. Several state GDL programs can be improved by moving their structures closer to an adequate implementation of that concept. The learner stage of a GDL system needs to be long enough for beginners to obtain a thorough introduction to the vagaries of driving. The second or intermediate stage needs to effectively limit exposure to known high risk conditions as novices adapt to being fully in charge of the vehicle. The benefits of GDL to date are due almost entirely to the risk-reducing conditions it implements. To improve the functioning of GDL will probably require a better understanding of teen driving than we presently have. The likelihood of further gains will be enhanced by efforts to learn more about the actual causes of teen crashes, the nature and type of teen driver exposures, and what parents do with their teens during the supervised driving stage of GDL. Without a better understanding of these, and other, phenomena it will be difficult to further reduce crashes among young beginning drivers, whether through GDL enhancements or with other approaches.  相似文献   
986.
The possibility of adopting national targets for carbon dioxide (CO2) emissions from tropical deforestation in a future international climate treaty has received increasing attention recently. This attention has been prompted by proposals to this end and more intensified talks on possible commitments for developing countries beyond the United Nations Framework Convention on Climate Change Kyoto Protocol. We analyze four main scientific and political challenges associated with national targets for emissions from tropical deforestation: (1) reducing the uncertainties in emission inventories, (2) preserving the environmental integrity of the treaty, (3) promoting political acceptance and participation in the regime, and (4) providing economic incentives for reduced deforestation. We draw the following conclusions. (1) Although there are large uncertainties in carbon flux from deforestation, these are in the same range as for other emissions included in the current Kyoto protocol (i.e., non-CO2 GHGs), and they can be reduced. However, for forest degradation processes the uncertainties are larger. A large challenge lies in building competence and institutions for monitoring the full spectrum of land use changes in developing countries. (2 and 3) Setting targets for deforestation is difficult, and uncertainties in future emissions imply a risk of creating ‘tropical hot air’. However, there are proposals that may sufficiently deal with this, and these proposals may also have the advantage of making the targets more attractive, politically speaking. Moreover, we conclude that while a full carbon accounting system will likely be politically unacceptable for tropical countries, the current carbon accounting system should be broadened to include forest degradation in order to safeguard environmental integrity. (4) Doubts can be cast over the possible effect a climate regime alone will have on deforestation rates, though little thorough analysis of this issue has been made.
U. Martin PerssonEmail:
  相似文献   
987.
Today and in the Tertiary, the geographical distribution of castorids is limited throughout all of the northern continents. Fossils of the Castoridae genus Steneofiber are abundant in many localities of Eurasia from the late Oligocene to Pliocene period. Recently, Steneofiber fossils were discovered in two localities of northern Thailand, Mae Moh and Chiang Muan coal mines, in layers of late middle Miocene age. These discoveries represent the first records of castorids from Southeast Asia and correspond to their southernmost known range. The focus of this study is to describe this new Thai species of Steneofiber and to define its wear stages from the molar occlusal surfaces by using micro-CT scan analysis. The CT scan technique permits the analysis of the virtual occlusal surface changes from wear, allowing easier comparison to related species of Steneofiber cheek teeth without destroying the teeth. The new species, Steneofiber siamensis n. sp., can be distinguished from the other species of Steneofiber by several distinct characters, longer mesostriid on p4, presence of premesostria and metastria on P4, which are smaller than most of the other known species. The occurrence of this new castorid also supports a subtropical to tropical paleoclimate for these two localities of northern Thailand.  相似文献   
988.
A comparative experiment was conducted to test the extent to which grazing of rank Molinia caerulea-dominated grassland increases botanical diversity and improves animal performance. The study was carried out on an area of under-grazed Molinia-dominant pasture that had not been stocked for 20 years. Three treatments were compared from 2001 until 2008: (1) no grazing, (2) grazing by Welsh Mountain sheep and (3) grazing by Welsh Black heifers. Patterns of change in sward surface composition across the grazing season were consistent with greater consumption of Molinia by the cattle, but there was little evidence of management regime influencing changes in sward composition year-on-year. There was a significant effect of year on animal performance (P < 0.001). Although the growth rates of the heifers improved over the course of the first three years of the experiment, this performance was not sustained. In contrast, any weight changes for the sheep were positive. The results highlight the slow pace of change within upland swards, and the need to develop site-specific grazing guidelines.  相似文献   
989.
The effects on different physico-chemical, chemical and biological soil properties of the incorporation of different organic materials into a calcareous vineyard soil were studied in an experiment during three growing seasons. The organic materials used were sheep manure and four composts derived from the treatment of winery and distillery wastes. A multivariate technique, factor analysis (FA), was also used for interpreting the data obtained from the samplings carried out throughout the three vine growing seasons. The application of the organic materials induced an increase in the activity of the soil microorganisms and in the soil macro and micronutrient contents, as well as a slow release of inorganic N. Through FA of the soil properties studied, three factors that explained 74.7% of the variability were established and the effects of the treatments after the whole experimental period were assessed.  相似文献   
990.
Achievement of at least “good ecological status” in all waterbodies under the EU Water Framework Directive by 2015 will in some cases be a challenge. The twin challenge is to manage expectations of policy makers for such waterbodies as to a realistic length of time required for improvement in water quality. Hence, understanding the source, transformation processes and residence time of nitrate in a hydrological system is an essential part of meeting such challenges. On a dairy farm with 24 shallow groundwater wells, the dual isotopic composition of nitrate (δ15N and δ18O) was used to clarify nitrate sources, to assess spatial and temporal variability in nitrate concentrations and to determine if and where denitrification was occurring. Vertical travel time was estimated to correlate nitrate concentrations with management practices. Organically derived nitrogen was the predominant source contributing to groundwater nitrate concentrations. Denitrification was identified as prevalent within specific regions of the study site. The distinct low temporal variability in the isotopic data suggests constancy among nitrate sources and processes over time across the study site. Vertical travel times of up to 3 years were estimated on site indicating the influence of recent management practices on nitrate concentrations. Very slow horizontal migration of groundwater (decades) indicates a legacy of older management practices. Stable isotope techniques, together with an understanding of time lag, provide an extra mechanism to test the efficacy of monitoring and mitigation programmes.  相似文献   
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