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31.
A lethal form of bone dysplasia, platylospondylic lethal chondrodysplasia, was diagnosed prenatally using three-dimensional ultrasound. The various types of three-dimensional imaging mode provided diagnostic details not available by conventional two-dimensional ultrasound. The diagnosis was made after referral in the 23rd week of gestation, allowing termination of pregnancy due to the poor prognosis. Prenatal sonograms were compared with postnatal radiographs.  相似文献   
32.
The authors analysed a proportional valve with electrical position feedback for its failure behaviour. Several failures were introduced into the feedback loop, especially into the 2 solenoids and the inductive position transducer. The behaviour of the valve for square and ramp reference signals was recorded and systematically analysed. It was shown that failures could be detected by monitoring the residual signal from the equipment under control or the residual signal from the sensor. It was possible to achieve the safe position within twice the normal response time of the valve by switching off the current of both solenoids. The application of these results for a new generation of safe proportional valves is discussed. The use of the results of these investigations obviates the need for redundancy of the electrical position monitoring arrangement in a safe proportional valve.  相似文献   
33.
The European Commission (EC) has recognized a need for strengthening innovation of environmental technologies in order to increase competitiveness of European technologies on a global market and to achieve a more sustainable development in Europe. In the area of soil and groundwater remediation, innovative technologies are principally available and have proven applicability and performance on demonstration scales, but market uptake is disappointing. Consequently, initiatives have been launched in order to promote application of these technologies and to investigate on the harmonization of applications. The European Co‐ordination Action for Demonstration of Efficient Soil and Groundwater Remediation (EURODEMO), an EC‐funded project, is one strategic initiative for supporting these goals. This article summarizes results obtained so far regarding the investigation of the European situation and some undertaken and envisaged measures to achieve better market uptake. The results of this research project may serve as prerequisites for a European Environmental Technologies Verification (ETV) process. © 2006 Wiley Periodicals, Inc.  相似文献   
34.
Farmland habitat diversity in marginal European landscapes changed significantly in the past decades. Further changes toward homogenization are expected, particularly in the course of European agricultural policy. Based on three alternative transfer payment schemes, we modeled spatially explicit potential effects on the farmland habitat diversity in a marginal European landscape. We defined (1) a scenario with direct transfer payments coupled to production, (2) a scenario with direct transfer payments decoupled from production, and (3) a scenario phasing out all direct transfer payments. We characterized habitat diversity with three indices: habitat richness, evenness, and rarity. The habitat pattern in 1995 served as reference for comparison. All scenarios predicted a general trend of homogenization of the farmland habitat pattern, yet to a differing extent. Transfer payments coupled to production (Scenario 1) favored the abandonment of agricultural production, particularly in low-productive areas and arable land use in more productive areas. Habitat richness and habitat evenness had intermediate values in this scenario. Decoupling transfer payments from production (Scenario 2) supported grassland as most profitable farming system. This led to a grassland-dominated landscape with low values of all habitat diversity indices. Phasing out transfer payments (Scenario 3) resulted in complete abandonment or afforestation of agricultural land and extremely low values in all habitat diversity indices. Scenario results indicate that transfer payments may prevent cessation of agricultural production, but may not counteract homogenization in marginal landscapes. Conserving high farmland habitat diversity in such landscapes may require support schemes, e.g., Pillar Two of EU Common Agricultural Policy.  相似文献   
35.
2  H). As a consequence, the former proteolytic enzyme gained peroxidase activity and catalyzed the selective reduction of hydroperoxides. Due to the identical binding sites of the semisynthetic peroxidase and the protease, the substrate selectivity of seleno-subtilisin was predictable in view of the well-known selectivity of subtilisin.  相似文献   
36.
The objective was to assess head injury risks and kinematics of adult pedestrians and bicyclists in primary impact to the passenger cars and secondary impact to the ground using real world accident data and computer reconstructions of the accidents. For this purpose, a subsample of 402 pedestrians and 940 bicyclists from the GIDAS database, Germany, was used for the statistical analysis, from which 22 pedestrian and 18 bicyclist accidents were further selected for reconstruction. PC-Crash was used to calculate impact conditions, such as vehicle impact velocity, vehicle kinematic sequence, and thrown distance. These conditions were employed to identify the initial conditions in reconstruction in MADYMO program. A comparable analysis was conducted based on the results from accident analysis and computer reconstructions for the impact configurations and the resulting injury patterns of pedestrians and bicyclists in view of head injury risks. Differences in HIC, head-relative impact velocity, linear acceleration, maximum angular velocity and acceleration, contact force, thrown distance, Wrap Around Distance (WAD), and head contact time were evaluated. Injury risk curves were generated by using a logistic regression model for vehicle impact velocity. The results indicate that bicyclists suffered less severe injuries compared with severity of pedestrian injuries. In the selected samples, the AIS 2+ and AIS 3+ head injury risks for pedestrians are 50% probability at impact speed of 38.87 km/h and 54.39 km/h respectively, while for bicyclists at 53.66 km/h and 58.89 km/h respectively. The findings of high injury risks suggested that in the area with high frequency car-pedestrian accidents, the vehicle speed limit should be 40 km/h, while in the area with high frequency car-cyclist accidents the vehicle speed limit should be 50 km/h.  相似文献   
37.
PROBLEM: By numerous accounts, alcohol abuse is considered the number one drug problem facing young people today. Alcohol consumption and its negative consequences, especially those due to drinking and driving, continue to have devastating effects on the college student population. METHOD: This field study examined the blood alcohol concentration (BAC) levels of male and female designated drivers (DD), non-DD, and their respective passengers as they were leaving drinking establishments in a university town. Also investigated were the effects of group size and gender on DD use. RESULTS: A 2 Gender x 2 Driver type (DD vs. non-DD) analysis of variance (ANOVA) for BAC indicated significant main effects for Gender and Driver type, with higher BAC for men and non-DD (p's<.001). A significant Gender x Driver type interaction (p<.05) was primarily due to female DD having lower BAC than male DD. In addition, larger groups were more likely to have a DD. IMPACT ON INDUSTRY: Results indicate that the success of DD programs may be influenced by group size and a DD's gender. While larger groups are more likely to have a DD, students riding home with a male DD may still be at risk for the negative consequences of drunk driving.  相似文献   
38.
Zusammenfassung  Im Rahmen praktischer Untersuchungen der Autoren zu Umweltmanagementsystemen in der Landwirtschaft, und hier insbesondere der Umweltprüfung, zeigen sich die Besonderheiten der Agrarwirtschaft im Implementierungsproze?. Einige Bereiche k?nnen relativ einfach umgesetzt werden, andere Aspekte bedürfen einer differenzierteren Methodik als bei anderen Wirtschaftsbereichen. W?hrend sich das Managementaudit durch die übersichtliche Organisationsstruktur landwirtschaftlicher Betriebe meist als unkritisch erweist, werden beim Wirkungsund Rechtsaudit einige bereichsspezifische Probleme erkannt. Das Wirkungsaudit zeigt dem Anwender nach der Einführung einer neuen, speziell auf die Landwirtschaft angepa?ten Methodik der Stoffstrombilanzierung praxisorientierte Handlungspotentiale. Die Ergebnisse k?nnen je nach Bedarf auf Betriebs-, Betriebszweigoder Kostentr?gerebene ausgewiesen relevant, da sie einhohes ?kologischen Gef?hrdungspotential besitzen und bei den praktischen Erhebungen h?ufig Gegenstand von Beanstandungen waren. Diese betreffen vor allem die Lagerung von umweltrelevanten Stoffen (Pflanzenschutzmittel, Diesel, Jauche, Gülle, Festmist oder Sickers?fte) sowie die etwaigen Notwendigkeit und Beschaffenheit eines Waschplatzes. Die Konfliktbereiche werden beschrieben und darauf aufbauend Optionen zur Verbesserung aufgezeigt. Online-Publikationsdatum: 20.12.1999  相似文献   
39.
The registration of the present situation regarding environmental investigation is the basis for efficiently proceeding in the course of the implementation of environmental management systems (EMS). The basic analysis is found on the individual elements: reaction audit, management audit and compliance audit. Via an optimal performance of an environmental investigation while implementing an EMS, the basis for a maximum utilization has been created for the user as well for agriculture. Utilization for the company is provided by documentation of the organizational structure showing a transparency of procedures with regard to efficiency. Furthermore, an EMS is useful in the course of external tasks, e.g. public approach, business partners, position to authorities, deregulation or minimization of liability.  相似文献   
40.
Atmospheric phosphine (PH3) fluxes from typical types of wetlands and PH3 concentrations in adjacent atmospheric air were measured. The seasonal distribution of PH3 in marsh and paddy fields were observed. Positive PH3 fluxes are significantly related to high air temperature (summer season) and increased vegetation. It is concluded that vegetation speeds up the liberation of PH3 from soils, while water coverage might function as a diffusion barrier from soils or sediments to the atmosphere. The concentrations of atmospheric PH3 (ng m−3) above different wetlands decrease in the order of paddy fields (51.8 ± 3.1) > marsh (46.5 ± 20.5) > lake (37.0 ± 22.7) > coastal wetland (1.71 ± 0.73). Highest atmospheric PH3 levels in marsh are found in summer. In paddy fields, atmospheric PH3 concentrations in flourishing stages are higher than those in slowly growing stages.  相似文献   
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