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141.
While studies of office environments have treated the customisation of technology by users as a positive response to the situated nature of work, customisation of devices in the medical domain, and other safety-critical domains, when acknowledged, has been treated understandably as a violation and a threat to safety. This paper looks at the customisation of medical devices by nursing staff, based on an observational study carried out in three Scottish intensive care units. Drawing on the insights of ethnomethodology, this paper proposes an alternative approach to the study of user customisation and its organisation. An attempt has been made to go beyond the simple categorisation of types of customisation to explicate the detail of how customisation is carried out. Drawing on concerns in human-computer interaction and arguments in medicine surrounding the use of protocols, the potential for supporting customisation in the medical domain is discussed.  相似文献   
142.
Mast cell populations in the vaginal cul-de-sac of female brushtail possums do not appear to be related to microbial invasion but changes in their density occur at oestrus, indicating a hormonal influence. The present study examined the effect of treatment with oestradiol on microflora and on mast cell numbers and their spatial location in cul-de-sac tissue of seasonally anoestrous brushtail possums. Tissue was collected from seasonally anoestrous brushtail possums (n = 6 per group) that were either untreated (anoestrous group) or were subjected to 6 days of treatment with oestradiol (oestradiol group) administered via subcutaneous implants or with the oil vehicle alone (control group). Tissue was collected aseptically for microbiological procedures and the fractionator and optical disector were used to quantify mast cell populations. Microflora populations were low (< 4.0 x 10(4) organisms g(-1)) and numbers of mast cells were similar in all groups. Mast cell density was greatest in epithelial and connective tissues from seasonally anoestrous and control animals and lowest in oestradiol-treated possums, in which there was a significant increase in cul-de-sac mass and volume. There is an inverse relationship between circulating oestrogen concentrations and mast cell density in possum cul-de-sac tissue, which is probably the result of an increase in tissue volume.  相似文献   
143.
Despite speculation about the role of vehicle insurance in road traffic accidents, there is little research estimating the direction or extent of the risk relationship. Data from the Auckland Car Crash Injury Study (1998–1999) were used to examine the association between driving an uninsured motor vehicle and car crash injury. Cases were all cars involved in crashes in which at least one occupant was hospitalized or killed anywhere in the Auckland region. Controls were 588 drivers of randomly selected cars on Auckland roads. Participants completed a structured interview. Uninsured drivers had significantly greater odds of car crash injury compared to insured drivers after adjustment for age, sex, level of education, and driving exposure (odds ratio 4.77, 95% confidence interval 2.94–7.75). The causal mechanism for insurance and car crash injury is not easily determined. Although we examined the effects of multiple potential confounders in our analysis including socioeconomic status and risk-taking behaviours, both of which have been previously observed to be associated with both insurance status and car crash injury, residual confounding may partly explain this association. The estimated proportion of drivers who are uninsured is between 5 and 15% in developed countries, representing a significant public health problem worthy of further investigation.  相似文献   
144.
Despite an increasing emphasis on the role of senior managementcognition in shaping organizational action, there have beenfew attempts to link top management mental models to strategicchoice in the face of discontinuous innovation. This paper uses23 years of data covering 15 major pharmaceutical firms to explorethe degree to which each firm's response to the revolution inbiotechnology was shaped by the senior team's recognition ofbiotechnology's importance. Controlling for a number of importantalternative explanations, we show that recognition may be animportant predictor of action, suggesting that cognition atthe most senior level can play a critical role in shaping establishedfirms' response to discontinuities.  相似文献   
145.
Physical gaming is a genre of computer games that has recently been made available for the home. But what does it mean to bring games home that were originally designed for play in the arcade? This paper describes an empirical study that looks at physical gaming and how it finds its place in the home. We discuss the findings from this study by organizing them around four topics: the adoption of the game, its unique spatial needs, the tension between visibility and availability of the game, and what it means to play among what we describe as the gaming circle, or players and non-players alike. Finally, we discuss how physical gaming in the home surfaces questions and issues for householders and researchers around adoption, gender and both space and place.  相似文献   
146.
The authors hypothesized that repeated rewarding electrical stimulation of the dorsal raphe can produce behavioral sensitization to psychostimulants. Groups of male rats were implanted with a stimulation electrode and preexposed to brain stimulation at parameters set to equate rewarding effectiveness across rats. Control groups were implanted with an electrode but never stimulated, or not implanted at all. Twenty-four hours after the 12th self-stimulation session, all groups were challenged with amphetamine (0.5 mg/kg, ip), nicotine (0.2 mg/kg, sc), or saline, and locomotor activity was measured for 1 hr. Locomotor responses to amphetamine and to nicotine were significantly greater in rats preexposed to brain stimulation. These findings suggest at least partial overlap of underlying substrates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
147.
There is good evidence that interference with the mesolimbic dopamine (DA) system results in impaired maternal responding in postpartum female rats. However, whether activation of the mesolimbic DA system is capable of promoting maternal behavior has not been investigated. This study examined whether increasing DA activity in various brain regions of pregnancy-terminated, naive female rats would stimulate the onset of maternal behavior. Experiments 1 and 2 examined the effects of microinjection of various doses (0, 0.2, or 0.5 μg/0.5 μl/side) of a D? DA receptor agonist, SKF 38393, or a D? DA receptor agonist, quinpirole, into the nucleus accumbens (NA) on latency to show full maternal behavior, and Experiment 3 determined the effects of SKF 38393 injection into a control site. Finally, because the medial preoptic area (MPOA) is also important for maternal behavior, receives DA input, and expresses DA receptors, the authors examined whether microinjection of SKF 38393 into MPOA was capable of stimulating the onset of maternal behavior. Results indicated that microinjection of SKF 38393 into either the NA or the MPOA facilitates maternal responding in pregnancy-terminated rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
148.
London's bus network is one of the largest and most comprehensive urban transport systems in the world. The contribution of buses is recognised by implementing a series of initiatives including bus priority at traffic signals. London has a long history of the implementation of bus priority at traffic signals. It has kept pace with the development of new technologies by updating its bus priority system. Now, London is moving towards a bus management system based on global positioning system (GPS), which will also be used to provide bus priority at traffic signals. The authors describe theoretical work carried out by TRG on behalf of Transport for London Bus Priority Team to tackle the challenge posed by locational error associated with GPS where a traffic signal is close to a bus stop  相似文献   
149.
Abstract— As digital display systems replace film traditionally used for reading radiographic images, resource‐intensive acceptance testing must be performed to ensure that quality meets and maintains desired specifications. If machine observers can replace human readers, whose performances are highly variable, the results will be more consistent and less costly. To be effective, however, the automated observers must track human performance. An approach for a model observer, validated with human readers, for the evaluation of the visibility of low‐contrast small targets in high‐resolution and mobile displays under different ambient illumination, will be described. The displays were tested using CDMAM‐like digital phantoms containing disks of varying diameters and contrasts on a flat background. For this task, we find the best indicator of display performance to be the display's ability to represent small luminance contrast, not resolution or pixel size. The results confirm that high‐resolution systems perform better under low illumination while illuminance has a minor impact on the mobile‐display performance. Finally, the results show that the machine observer tracks the performance of human readers. Machine observers with proper validation can replace humans in the acceptance testing procedures, saving the testers both time and money.  相似文献   
150.
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