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22.
Objective: The objective of this study was to explore passengers’ comfort experience of extra seat belts during on-road driving in the rear seat of a passenger car and to investigate how the use of extra belts affects children's and adults’ attitudes to the product.

Methods: Two different seat belt systems were tested, criss-cross (CC) and backpack (BP), consisting of the standard 3-point belt together with an additional 2-point belt. In total, 32 participants (15 children aged 6–10, 6 youths aged 11–15, and 11 adults aged 20–79, who differed considerably in size, shape, and proportions) traveled for one hour with each system, including city traffic and highway driving. Four video cameras monitored the test subject during the drive. Subjective data regarding emotions and perceived discomfort were collected in questionnaires every 20 min. A semistructured interview was held afterwards.

Results: All participant groups accepted the new products and especially the increased feeling of safety (P <.01); 56% preferred CC and 44% preferred BP but the difference was not significant. In total, 81% wanted to have extra seat belts in their family car. CC was appreciated for its symmetry, comfort, and the perceived feeling of safety. Some participants found CC unpleasant because the belts tended to slip close to the neck, described as a strangling feeling. BP was simpler to use and did not cause annoyance to the neck in the way CC did. Instead, it felt asymmetric and to some extent less safe than CC. Body size and shape affected seat belt fit to a great extent, which in turn affected the experience of comfort, both initially and over time. Perceived safety benefit and experienced comfort were the most determinant factors for the attitude toward the extra seat belts. The extra seat belts were perceived as being better than the participants had expected before the test, and they became more used to them over time.

Conclusion: This exploratory study provided valuable knowledge from a user perspective for further development of new seat belt systems in cars. In addition to an increased feeling of safety, seat belt fit and comfort are supplementary influencing factors when it comes to gaining acceptance of new seat belt systems.  相似文献   
23.
Plant communities on plots with different metal pollution levels were compared in a field study in order to select the most suitable plant species for the direction of secondary succession toward the targeted grassland vegetation. The vegetational succession showed a gradual increase in plant cover and the number of plant species on the less polluted locations. Two predominant grass species Calamagrostis varia and Sesleria caerulea were selected for phytostabilisation, but a severely reduced seed germination capacity obstructed their use in practice. The mycorrhizal succession showed a gradual replacement of non-mycorrhizal with mycorrhizal plant species. Similar levels of arbuscular mycorrhizal colonisation of a particular plant species may be developed within each growing season regardless of the levels of pollution, with the exception of vesicle/intraradical spore formation. The results suggest that lower overall mycorrhizal colonisation levels and increased vesicle/spore formation may be a part of a mycorrhizal strategy at the most polluted locations.  相似文献   
24.
ABSTRACT

Quests for devolving more power to local actors for nature protection stem from both international and national policies. Also, there is a growing recognition of the need for local governments to promote green infrastructure for citizens to recreate and learn about their environment. Starting in 2004, the Swedish government has allocated special funding towards these goals through the Local Nature Conservation Programme (LONA). Virtually all Swedish municipalities have received such funding in pursuit of facilitating wide access to nature and promoting recreational activities, including the protection of nature areas, creating pathways, information devices, and promoting these areas among new societal groups to enjoy. This study presents the results of ten years of experience with LONA. A survey with respondents from 191 municipalities and 20 county administrations, together with 20 key informant interviews, show that the programme has been a success in several respects. Not only have most municipalities created a wealth of new ways to engage local organisations and citizens in nature conservation and recreation, but they have also broadened the ways they think about how nature is important to their constituencies. Due to innovative ways to count voluntary work as local matching of funding, smaller and less resourceful municipalities have also become engaged. Still, the local needs for further initiatives are deemed considerable. State support coupled with knowledge sharing is important to show policy priority to such bottom-up initiatives.  相似文献   
25.
The accumulation of P in agricultural soils due to fertilization has increased the risk of P losses from agricultural fields to surface waters. In risk assessment systems for P losses, both P release from soil to solution and transport mechanisms need to be considered. In this study, the overall objective was to identify soil variables for prediction of potential P release from soil to solution. Soils from nine sites of the Swedish long-term fertility experiment were used, each with four soil P levels. Phosphorus extractable with CaCl2 was used as an estimate of potential P release from soil to solution. Ammonium lactate-extractable phosphorus (P-AL) or NaHCO3-extractable phosphorus (Olsen P) could not be used alone for prediction of potential P release since soils with high phosphorus sorption capacity (PSC) released less P than soils with low PSC at the same soil test phosphorus (STP) level. Degree of phosphorus saturation (DPS) was calculated as Olsen P or P-AL as a percentage of PSC derived from P sorption isotherms or from Fe and Al extractable in ammonium oxalate. The CaCl2-extractable total phosphorus (CaCl2-TP) was exponentially related to these DPS values (r2 > or = 0.79). The CaCl2-TP was also linearly related to ratios between Olsen P or P-AL and a single-point phosphorus sorption index (PSI; r2 > or = 0.86). These ratios, which are easily determined and gave good correlations with CaCl2-TP, seemed to be the most useful estimates of potential P release for risk assessment systems.  相似文献   
26.
The series of papers in this issue of AMBIO represent technical presentations made at the 7th International Phosphorus Workshop (IPW7), held in September, 2013 in Uppsala, Sweden. At that meeting, the 150 delegates were involved in round table discussions on major, predetermined themes facing the management of agricultural phosphorus (P) for optimum production goals with minimal water quality impairment. The six themes were (1) P management in a changing world; (2) transport pathways of P from soil to water; (3) monitoring, modeling, and communication; (4) importance of manure and agricultural production systems for P management; (5) identification of appropriate mitigation measures for reduction of P loss; and (6) implementation of mitigation strategies to reduce P loss. This paper details the major challenges and research needs that were identified for each theme and identifies a future roadmap for catchment management that cost-effectively minimizes P loss from agricultural activities.  相似文献   
27.

Objectives

We aimed to compare cell-based NIPT (cbNIPT) to chorionic villus sampling (CVS) and to examine the test characteristics of cbNIPT in the first clinical validation study of cbNIPT compared to cell-free NIPT (cfNIPT).

Material and Methods

Study 1: Women (N = 92) who accepted CVS were recruited for cbNIPT (53 normal and 39 abnormal). Samples were analyzed with chromosomal microarray (CMA). Study 2: Women (N = 282) who accepted cfNIPT were recruited for cbNIPT. cfNIPT was analyzed using sequencing and cbNIPT by CMA.

Results

Study 1: cbNIPT detected all aberrations (32/32) found in CVS: trisomies 13, 18 and 21 (23/23), pathogenic copy number variations (CNVs) (6/6) and sex chromosome aberrations (3/3). cbNIPT detected 3/8 cases of mosaicism in the placenta. Study 2: cbNIPT detected all trisomies found with cfNIPT (6/6) and had no false positive (0/246). One of the three CNVs called by cbNIPT was confirmed by CVS but was undetected by cfNIPT, two were false positives. cbNIPT detected mosaicism in five samples, of which two were not detected by cfNIPT. cbNIPT failed in 7.8% compared to 2.8% in cfNIPT.

Conclusion

Circulating trophoblasts in the maternal circulation provide the potential of screening for aneuploidies and pathogenic CNVs covering the entire fetal genome.  相似文献   
28.
The application of plant essential oils (EOs) (hyssop and marjoram) was evaluated for inactivation of non-enveloped viruses using murine norovirus and human adenovirus as models. No significant reduction of virus titres (TCID50) was observed when EOs were used at different temperatures and times.  相似文献   
29.
This paper analyzes the economic impacts of summer drought on Swiss grassland production. We combine field trial data from drought experiments in three different grasslands in Switzerland with site-specific information on economic costs and benefits. The analysis focuses on the economic implications of drought effects on grassland yields as well as grassland composition. In agreement with earlier studies, we found rather heterogeneous yield effects of drought on Swiss grassland systems, with significantly reduced yields as a response to drought at the lowland and sub-alpine sites, but increased yields at the wetter pre-alpine site. Relative yield losses were highest at the sub-alpine site (with annual yield losses of up to 37 %). However, because income from grassland production at extensive sites relies to a large extent on ecological direct payments, even large yield losses had only limited implications in terms of relative profit reductions. In contrast, negative drought impacts at the most productive, intensively managed lowland site were dominant, with average annual drought-induced profit margin reductions of about 28 %. This is furthermore emphasized if analyzing the farm level perspective of drought impacts. Combining site-specific effects at the farm level, we found that in particular farms with high shares of lowland grassland sites suffer from summer droughts in terms of farm-level fodder production and profit margins. Moreover, our results showed that the higher competitiveness of weeds (broad-leaved dock) under drought conditions will require increasing attention on weed control measures in future grassland production systems. Taking into account that the risk of drought occurrence is expected to increase in the coming years, additional instruments to cope with drought risks in fodder production and finally farmers’ income have to be developed.  相似文献   
30.
Cytostatic drugs are among the most toxic chemicals which are produced. Many of them cause damage of the genetic material which may affect the fertility of higher organisms. To study the impact of the widely used anticancer drugs [cisplatin (CisPt), etoposide (Et), and 5-fluorouracil (5-FU)] on the reproduction of higher plants, pollen abortion experiments were conducted with species which belong to major plant families, namely with Tradescantia paludosa (Commelinaceae), Arabidopsis thaliana (Brassicaceae), Chelidonium majus (Papaveraceae), and Alisma plantago-aquatica (Alismataceae). All compounds increased the frequencies of abortive grains. The lowest effective doses were in general in a narrow range (i.e., 1 and 10 mg/kg of dry soil). The effects of the individual drugs were similar in T. paludosa, A. plantago-aquatica, and Ch. majus, while A. thaliana was consistently less sensitive. The highest abortion rate was obtained in most experiments with CisPt, followed by 5-FU and Et. Comparisons of the doses which caused effects in the present experiments in the different species with the predicted environment concentrations and with the levels of the cytostatics which were detected in hospital wastewaters show that the realistic environmental concentrations of the drugs are 4–6 orders of magnitude lower. Therefore, it is unlikely that these drugs affect the fertility of higher plants in aquatic and terrestrial ecosystems.  相似文献   
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