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11.
Basic taste solutions induce sensory perceptions via taste receptors and give rise to specific facial reactions. Many of these have been shown to be innate. The aim of this study was to explore relationships between the sensory perception of basic taste solutions at different concentrations and facial reactions.Basic taste solutions each at three levels plus water were served to a panel. The assessors individually identified quality, intensity and pleasantness. They were recorded during tasting and their facial reactions (based on FACS) were coded and analysed.Facial reactions indicated both quality and concentration of the stimuli. The intensity of most facial reactions increased with increasing stimulus concentration, most pronounced for sourness (lips) and bitterness (eyes and forehead). Pleasantness ratings decreased with increasing concentrations of all basic tastes. Water and the lowest sucrose concentration were perceived as the most pleasant samples and gave rise to the lowest intensity of facial reactions. The study showed that a combination of sensory analyses and facial expressions was successful in adding further insight to the knowledge of perception of basic tastes.  相似文献   
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Thymus vulgaris has a chemical polymorphism with six different chemotypes that show marked spatial segregation in nature. Although some populations have a single chemotype in majority, many have two or three chemotypes. In this study we analyze the quantitative variation among T. vulgaris populations in the percentage of oil composed of the dominant monoterpene(s) for each chemotype. In general, phenolic chemotypes (thymol and carvacrol), which occur at the end of the biosynthetic chain, have a significantly lower proportion of their oil composed of their dominant monoterpene than nonphenolic chemotypes (geraniol, -terpineol, and linalool). This is due to the presence of high amounts of precursors (-terpinene and paracymene) in the oil of phenolic chemotypes. The essential oil of the nonphenolic thuyanol chemotype has four characteristic monoterpenes that together make up a lower proportion of the oil than the single dominant monoterpene of the other nonphenolic chemotypes. For all chemotypes, the percentage composition of the dominant monoterpene decreased significantly at sites where the chemotype is not the majority type. This decrease is correlated with a significant increase in either the proportion of the two precursors for the thymol chemotype or the monoterpenes characteristic of the other chemotypes at the site. The latter result suggests that a plant with dominant genes is responsible for the production of different monoterpenes can produce several molecules.  相似文献   
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Nanofluidic devices are rapidly emerging as tools uniquely suited to transport and interrogate single molecules. We present a simple method to rapidly obtain compact surfactant nanotube networks of controlled geometry and length. The nanotubes, 100-300 nm in diameter, are pulled from lipid vesicles using a micropipet technique, with multilamellar vesicles serving as reservoirs of surfactant material. In a second step, the nanotubes are wired around microfabricated SU-8 pillars. In contrast to unrestrained surfactant networks that minimize their surface free energy by minimizing nanotube path length, the technique presented here can produce nanotube networks of arbitrary geometries. For example, nanotubes can be mounted directly on support pillars, and long stretches of nanotubes can be arranged in zigzag patterns with turn angles of 180 degrees. The system is demonstrated to support electrophoretic transport of colloidal particles contained in the nanotubes down to the limit of single particles. We show that electrophoretic migration velocity is linearly dependent on the applied field strength and that a local narrowing of the nanotube diameter results from adhesion and bending around SU-8 pillars. The method presented here can aid in the fabrication of fully integrated and multiplexed nanofluidic devices that can operate with single molecules.  相似文献   
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AIMS: To estimate the association between per capita alcohol consumption and fatal accidents in the United States and to compare the outcome with findings from Europe and Canada. DATA AND METHOD: Yearly data on fatal accidents by gender and age were analysed in relation to per capita alcohol consumption for 1950-2002 using the Box-Jenkins technique for time series analysis. FINDINGS: A 1-L increase in per capita consumption was on average followed by 4.4 male deaths per 100,000 inhabitants, but had no significant effect on female accident mortality. Regarding specific categories of accidents, the effect on fatal motor vehicle accidents accounted for a large part of the overall effect for men and was also significant for women. With respect to fatal falling accidents and other accidents, the only significant effects were found among young males. As concerns women, the association with per capita consumption in the US was weak in comparison with Canada and Europe. The US effect estimate for overall male accidents was however equally strong as in Northern Europe (5.2) or Canada (5.9), and stronger than that found in Central and Southern Europe (2.1 and 1.6, respectively). With respect to alcohol and fatal motor vehicle accidents, the association for men of 3.2 was stronger than in Europe and more similar to the Canadian finding (3.6). CONCLUSIONS: Per capita alcohol consumption has at least partly been an explanation for the development of male fatal accidents and particularly motor vehicle accident rates in the post-war United States. High traffic density and relatively high legal limits for drunken driving blood alcohol concentration (BAC) are suggested to explain the strong association found between alcohol and fatal motor vehicle accidents. The results also suggest that a reduction in per capita consumption would have its most preventive impact on fatal accidents among younger males.  相似文献   
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Domestic life and domestic work are often studied in a family setting that only includes members of the focal family unit. However, when opening the home for guests, family life becomes both a back and front stage arena, where guests are relaxed but hosts are not. Being a host includes not only domestic chores but also “doing” identity, relations, and friendship. In this article, we combine Goffman's work with thirteen qualitative interviews from Denmark to investigate domestic hospitality and hosts' perceptions hereof. Domestic hospitality involves not only “putting on a show” but also extensive preparation and complex assessments of appropriate levels of staging. Such staging depends on occasions, host-guest relations, and hosts' predispositions. We discuss how reflexive and well-educated women, who are aware of their “putting on a show,” nevertheless put on such “shows.” Even in Denmark, which is rather progressive in terms of gender equality compared to other European countries, gender still matters and affects women's self-conceptualizations in domestic hospitality. It is well known that people manage the impressions they seek to make and adapt to different types of guests, but the contribution of this article is to pinpoint the extent to which the participants are aware of these processes, and of the fact that they are sometimes almost ridiculous, but still cannot not care.  相似文献   
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Selecting appropriate ventilator settings decreases the risk of ventilator-induced lung injury. A decision support system (DSS) has been developed based on physiological models, which can advise on setting of tidal volume (Vt), respiratory frequency (f) and fraction of inspired oxygen (FiO2). The aim of this study is to assess the feasibility of the DSS by comparing its advice with the values used in clinical practice. Data from 20 patients following uncomplicated coronary artery bypass grafting (CABG) with cardiopulmonary bypass was used to test the DSS. Ventilator settings suggested by the DSS were compared to the settings selected by the clinician. When compared to the clinician the DSS suggested: lowering FiO2 (by median 7%, range 2-17%) at high SpO2 and increasing FiO2 (by median 2%, range 1-5%) at low SpO2; lowering ventilation volume (by median 0.57 l min(-1), range 0.2-1.1 l min(-1)) at high pHa and increasing ventilation volume (by median 0.4 l min(-1), range 0.1-0.9 l min(-1)) at low pHa. Suggested changes in ventilation volume were such that simulated values of PIP were < or = 22.9 cmH2O and respiratory frequency < or = 18 breaths min(-1). In all cases, computer suggested values of FiO2, Vt or f were consistent with maintaining sufficient oxygenation, normalising pH and obtaining low values of PIP.  相似文献   
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An online survey in the form of a questionnaire was conducted to obtain the opinion of computer users with tetraplegia on their current computer interfaces and to assess desirable applications for future independent control using assistive devices. The survey included questions related to information about the respondents' injury/disease, everyday activities and social life, electronic devices and computer programs, evaluation of computer interfaces, and desirable applications for assistive devices. The survey was distributed via tetraplegia associations, magazines, and Internet forums mainly in Denmark and Sweden, but also through other European and American associations. Thirty-one completed questionnaires were collected from individuals with spinal cord injury and other neuromuscular diseases that resulted in tetraplegia. Respondents evaluated gaze and head trackers; speech recognition systems; chin, mouth, and hand joysticks; sip and puff interfaces; and typing sticks. Most interfaces were evaluated in a range from neutral to good. Users expressed a desire for applications to independently control wheelchairs, television sets, doors, and windows. This is, as far as is known, the first study that compares a wide range of current commercial computer interfaces that have been used as part of the users' everyday lives. The answers are useful for designing and developing alternative computer interfaces and assistive devices and for computer-interface users to identify a computer-interface fitting more to his or her needs.  相似文献   
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