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Objective: Adaptive cruise control (ACC), a technology that allows for automated car following, is becoming increasingly prevalent. Previous surveys have shown that drivers generally regard ACC as pleasant but that they have to intervene when the ACC reaches its operational limits. The former research has been mostly concerned with specific car brands and does not fully reflect the diversity of ACC types in traffic today. The objective of the present research was to establish the determinants of pleasure in using ACC.

Methods: A 55-item online questionnaire was completed by Dutch users of diverse ACC systems.

Results: Respondents (N = 182) rated their ACC highly, with a mean score of 8.0 on a scale from 1 (extraordinarily negative) to 10 (extraordinarily positive) and were most pleased with ACC on high-speed roads and in low-density traffic. Moreover, the findings point to specific operational limits such as associated with cut-in situations. Pleasure was greater for the types of ACC that are able to decelerate to a full stop, according to 48% of our sample. An analysis of the free-response items indicated that respondents who were displeased with ACC mentioned its occasional clumsiness and the dangerous situations it may evoke, whereas those who were pleased with ACC valued the complementarity of human and machine and emphasized the roles of responsibility and experience in using ACC.

Conclusion: Pleasure in using ACC is a function of both technological advances and human factors.  相似文献   

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Hepatitis A virus (HAV) is currently recognized as an important human food borne pathogen, and it is one of the most resistant enteric RNA viruses, is highly infectious, and may lead to widespread outbreaks. The aim of this study was to optimize the methods to detect HAV from artificially contaminated food. To this end, strawberry and lettuce were experimentally contaminated with HAV suspension containing 6 × 106 copies/ml. After contamination, HAV persistence and washing procedure were evaluated at 0, 1, 3, 7, and 9 days of storage. Five elution buffers (PBS (pH 7.4)/0.1% Tween80; 50 mM glycine/3% (wt/vol) beef extract (pH 9.5); PBS (pH 7, 4); 25 mM glycine/0.1 Tween80; and 1 M sodium bicarbonate) were used to elute the virus, and qualitative and quantitative PCR were used for HAV detection. HAV was detected by qualitative and quantitative PCR using any of the five elution buffers, but PBS was the most effective. Even after washing, HAV was detected up to 9 days after contamination by quantitative PCR. Quantitative PCR was more sensitive than qualitative PCR since samples containing viral load lower than 1.4 × 103 copies/ml could not be detected by qualitative PCR. Quantitative PCR can be used for rapid detection of food borne viruses and will help in the monitoring and control of food borne disease.  相似文献   
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This study examined behavioral and enzymatic changes of C. elegans from its exposure to aluminum, and the resulting relationship with Alzheimer's disease. After chronic and acute exposure to aluminum, the results indicated that it alters the cholinergic status and behavior parameters of the nematode, suggesting a relationship between exposure to aluminum and the etiology of AD.  相似文献   
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Somatic coliphages were quantified in 459 produce and environmental samples from 11 farms in Northern Mexico to compare amounts of somatic coliphages among different types of fresh produce and environmental samples across the production steps on farms. Rinsates from cantaloupe melons, jalapeño peppers, tomatoes, and the hands of workers, soil, and water were collected during 2011–2012 at four successive steps on each farm, from the field before harvest through the packing facility, and assayed by FastPhage MPN Quanti-tray method. Cantaloupe farm samples contained more coliphages than jalapeño or tomato (p range <0.01–0.03). Across production steps, jalapeños had higher coliphage percentages before harvest than during packing (p = 0.03), while tomatoes had higher coliphage concentrations at packing than all preceding production steps (p range <0.01–0.02). These findings support the use of targeted produce-specific interventions at multiple points in the process of growing and packing produce to reduce the risk of enteric virus contamination and improve food safety during fruit and vegetable production.  相似文献   
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