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121.
In 226 women requesting chorionic villus sampling (CVS), routine cervical cultures were obtained before the procedure. Transcervical CVS was performed irrespective of the test results. The prevalence of potential pathogens in cervical cultures at our institution is low. Beta haemolytic Streptococcus was cultured in 3 per cent of the women. No pathogenic microorganisms were isolated in 64 per cent of the women. There was no relationship between culture results and the outcome of pregnancy. These observations suggest that adequate antiseptic cleansing of the genital tract is a suitable approach and there is no need to routinely perform cultures before CVS.  相似文献   
122.
PROBLEM: Young male novice drivers are overrepresented in injury motor-vehicle crashes compared to females in the same category. This difference in crash involvement is often assumed to include factors such as overestimation, risk acceptance, and sensation seeking, but it can also be related to acquisition of knowledge, skills, insight, and driving experience. Therefore, this study explored possible gender differences among 18-24-year-olds in Sweden regarding practicing as learners, outcome of the driver's tests, and crash involvement during the first year after licensure. METHOD: Data for 2005 from different sources (e.g., questionnaires, license test, and crash statistics) were examined. It was not possible to follow individual subjects through all stages or in all analyses. Nevertheless, the study design did enable scrutinization and discussion of gender differences between younger inexperienced drivers with respect to education and training, license test results, and initial period of licensure. RESULTS: Males and females assimilated tuition in different ways. Females studied more theory, pursued training in a more structured manner, practiced more elements of driving in several different environments, and participated more extensively in driving school instruction. National statistics showed that females did better on the written test but not on the driving test. Males were involved in 1.9 more injury crashes per 1,000 drivers than females during their first year of licensed driving. The proportional distribution of crash types was the same for both sexes during the first period as novice drivers, but the circumstances surrounding the accidents varied (e.g., males were involved in more night crashes). IMPACT ON TRAFFIC SAFETY: More structured training while learning appears to be one of the reasons why females initially do better than males as novice drivers. Therefore, in the future, driver education should focus not only on matters such as the amount of time spent on training and preconditioning, but also on the importance of the organization and content of the learning process.  相似文献   
123.
Energy efficiency in the residential housing market can play an important role in the reduction of global carbon emissions. This paper reports the first evidence on the market adoption and economic implications of energy performance certificates implemented by the European Union. The results show that adoption rates are low and declining over time, coinciding with a negative sentiment regarding the label in the popular media. Labels are clustered among smaller, post-war homes in neighborhoods with more difficult selling conditions. We also document that geographic variation in the adoption rate of energy labels is positively related to the fraction of “green” voters during the 2006 national elections. Within the sample of labeled homes, the energy label creates transparency in the energy efficiency of dwellings. Our analysis shows that consumers capitalize this information into the price of their prospective homes.  相似文献   
124.
125.
Adverse effects of agrochemicals on earthworms’ burrowing behaviour can have crucial impacts on the entire ecosystem. In the present study, we have therefore assessed short- and long-term effects on burrowing behaviour in the earthworm species Aporrectodea caliginosa and Lumbricus terrestris after exposure to a range of imidacloprid concentrations (0.2-4 mg kg−1 dry weight (DW)) for different exposure times (1, 7, 14 d). 2D-terraria were used for the examination of post-exposure short-term effects (24-96 h), while post-exposure long-term effects were assessed by means of X-ray burrow reconstruction in three dimensional soil cores (6 weeks). For the latter each core was incubated with two specimens of L. terrestris and four of A. calignosa. Short-term effects on the burrowing behaviour (2D) of A. caliginosa were already detected at the lowest test concentration (0.2 mg kg−1 DW), whereas such effects in L. terrestris were not observed until exposure to concentrations 10 times higher (2 mg kg−1 DW). For both species tested in the 2D-terraria, “total burrow length after 24 h” and “maximal burrow depth after 24 h” were the most sensitive endpoints. 3D reconstructions of the burrow systems made by both earthworm species in the repacked soil cores revealed a significant linear decrease in burrow volume with increasing imidacloprid concentration.Since many of the observed effects occurred at imidacloprid concentrations relevant to natural conditions and since reduced activities of earthworms in soils can have crucial impacts on the ecosystem level, our results are of environmental concern.  相似文献   
126.
Coastal areas are exposed to a variety of threats due to high population densities and rapid economic development. How will this affect human welfare and our dependence on nature's capacity to provide ecosystem goods and services? This paper is original in evaluating this concern for major habitats (macroalgae, seagrasses, blue mussel beds, and unvegetated soft bottoms) in a temperate coastal setting. More than 40 categories of goods and services are classified into provisional, regulating, and cultural services. A wide variety of Swedish examples is described for each category, including accounts of economic values and the relative importance of different habitats. For example, distinguishing characteristics would be the exceptional importance of blue mussels for mitigation of eutrophication, sandy soft bottoms for recreational uses, and seagrasses and macroalgae for fisheries production and control of wave and current energy. Net changes in the provision of goods and services are evaluated for three cases of observed coastal ecosystem shifts: i) seagrass beds into unvegetated substrate; ii) unvegetated shallow soft bottoms into filamentous algal mat dominance; and iii) macroalgae into mussel beds on hard substrate. The results are discussed in a management context including accounts of biodiversity, interconnectedness of ecosystems, and potential of economic valuation.  相似文献   
127.
Possible links between plasma testosterone levels, heavy metal loads and dominance in juvenile male willow tits (Parus montanus) are studied during winter conditions in Norway. Dominant individuals have better access to food resources, significantly higher cadmium content in the liver and higher plasma testosterone level compared to subordinates. A positive correlation was also found between plasma testosterone level and content of cadmium in the liver. Although the results in our study shows only a limited difference in testosterone level of dominant and subordinate juvenile male willow tits, possible small changes in behaviour might have crucial effects on winter survival of these birds.  相似文献   
128.
Alumina used in the production of primary aluminium contains Be which partly vaporises from the cryolite bath into the workroom atmosphere. Since Be may be toxic at lower exposure levels than previously thought, the personal exposure to Be among workers in 7 Norwegian primary smelters has been assessed. In total, 480 personal Respicon? virtual impactor full shift air samples have been collected during 2 sampling campaigns and analysed for water soluble Be, Al and Na using inductively coupled plasma optical emission spectrometry. In addition, water soluble F(-) has been measured by ion chromatography. The Be air concentrations in the inhalable, thoracic and respirable aerosol fractions have been calculated. The Be concentrations in the inhalable aerosol fraction vary between the different smelters. The highest GM concentration of Be in the inhalable fraction (122 ng m(-3), n = 30) was measured in the prebake pot room of a smelter using predominantly Jamaican alumina where also the highest individual air concentration of 270 ng m(-3) of Be was identified. The relative distribution of Be in the different aerosol fractions was fairly constant with the mean Be amount for the two sampling campaigns between 44-49% in the thoracic fraction expressed as % of the inhalable amount. Linear regression analysis shows a high correlation between water soluble Be, Al, F and Na describing an average measured chemical bulk composition of the water soluble thoracic fraction as Na(5.7)Al(3.1)F(18). Be is likely to be present as traces in this particulate matter by replacing Al atoms in the condensed fluorides and/or as a major element in a nanoparticle sized fluoride. Thus, the major amount of Be present in the work room atmosphere of Al smelter pot rooms will predominantly be present in combination with substantial amounts of water soluble Al, F and Na.  相似文献   
129.
The aim of this study was to characterise personal exposures to dust, acid vapours, and gases among workers in a Norwegian nitrate fertiliser production plant, as part of an ongoing epidemiological study. In total, 178 inhalable and 179 thoracic aerosol mass fraction samples were collected from randomly chosen workers (N = 141) from three compound fertiliser departments (A, B and C), a calcium nitrate fertiliser production department, nitric acid- and ammonia-production departments, and a shipping department. The overall median inhalable and thoracic aerosol mass concentrations were generally low (1.1 mg m(-3) (min-max: <0.93-45) and 0.21 mg m(-3) (min-max: <0.085-11), respectively). Workers at the compound fertiliser departments B and C had significantly higher inhalable aerosol mass air concentrations compared to the other departments (p < 0.05), except for compound fertiliser department A; however, the difference between the compound fertiliser department C and calcium nitrate department was slightly above the significant level. Workers at the compound fertiliser department A had significantly higher thoracic aerosol mass air concentrations compared to the other departments (p < 0.05), except for compound fertiliser departments B and C. The results indicate that the extrathoracic aerosol fraction of the aerosol compared to the thoracic fraction dominated in most departments. Measurement of the main constituents Ca, K, Mg, and P in the water-soluble and water-insoluble aerosol mass fractions showed that the air concentrations of these elements were low. There is, however, a shift towards more water-soluble species as the production goes from raw material with phosphate rock towards the final product of fertilisers. Overall, the arithmetic mean of water-soluble Ca in the thoracic mass fraction was 51% (min-max: 1-100). A total of 169 personal samples were analysed for HNO(3) vapour and HF. The highest median concentration of HNO(3) (0.63 mg m(-3)) was in the compound fertiliser departments B, and all measurements but four of the HF concentrations were below the LOD of 190 μg m(-3). Exposures to NH(3), CO and NO(2) were measured using direct-reading electrochemical sensors and the time weighted overall averages were all below the LODs of the respective sensors, NH(3) 2 ppm; CO 2 ppm; and NO(2) 0.2 ppm, but some short-term peaks were detected. Even though our results indicate that the workers may experience peak exposure episodes when performing job tasks such as cleaning or maintenance work, the overall air concentrations are well below what is considered to cause known health risks.  相似文献   
130.
Whereas there is evidence that mixed-species approaches to production forestry in general can provide positive outcomes relative to monocultures, it is less clear to what extent multiple benefits can be derived from specific mixed-species alternatives. To provide such insights requires evaluations of an encompassing suite of ecosystem services, biodiversity, and forest management considerations provided by specific mixtures and monocultures within a region. Here, we conduct such an assessment in Sweden by contrasting even-aged Norway spruce (Picea abies)-dominated stands, with mixed-species stands of spruce and birch (Betula pendula or B. pubescens), or spruce and Scots pine (Pinus sylvestris). By synthesizing the available evidence, we identify positive outcomes from mixtures including increased biodiversity, water quality, esthetic and recreational values, as well as reduced stand vulnerability to pest and pathogen damage. However, some uncertainties and risks were projected to increase, highlighting the importance of conducting comprehensive interdisciplinary evaluations when assessing the pros and cons of mixtures.  相似文献   
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