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1.
Examining several sources of data on smartphone use, this paper presents evidence for the popular conjecture that mobile devices are “habit-forming.” The form of habits we identified is called a checking habit: brief, repetitive inspection of dynamic content quickly accessible on the device. We describe findings on kinds and frequencies of checking behaviors in three studies. We found that checking habits occasionally spur users to do other things with the device and may increase usage overall. Data from a controlled field experiment show that checking behaviors emerge and are reinforced by informational “rewards” that are very quickly accessible. Qualitative data suggest that although repetitive habitual use is frequent, it is experienced more as an annoyance than an addiction. We conclude that supporting habit-formation is an opportunity for making smartphones more “personal” and “pervasive.”  相似文献   
2.
How the human central nervous system adjusts sensorimotor coordination to haptic stimuli is a major topic in several fields including robotics. There are studies focusing on contact positioning tasks such as catching a ball or a volley in tennis, where position control of a human hand is required only at the moment of contact for successful completion of the tasks. A previous study dealt with a task of catching a ball in a virtual environment, and reported an interesting observation of the learning process in the relationship between operational performance and energy consumption of an operator; however, the operational condition given to the operators in the previous study seemed to be relatively simple. The interest in this paper is similar to that of the previous study; however, this paper considers application of a slightly more complex operational condition to a task of catching a ball. For corresponding to increase of difficulty in operation in the task, two movements of a paddle for catching a ball are given to operators, and difference between the movements is observed. Although the final goal of the study in this paper is similar to that in the previous study, this paper considers how learning effect can be observed in operational performance by comparing the performance of novice operators with that of experienced operators. The comparison shows differences in the performances between the operators from three analytic aspects. This paper also considers how many operations are required for novice operators to exhibit the learning effect in operational performance.  相似文献   
3.
Dietary carotenoids are important pigments, antioxidants, and immune-stimulants for birds. Despite recent interest in carotenoids in bird ecology, we know surprisingly little about the carotenoid content of invertebrates consumed by birds. We compared carotenoid (lutein, β-carotene, and total) concentrations in invertebrates brought to nestlings by two insectivorous passerines, the great tit, Parus major and the pied flycatcher, Ficedula hypoleuca. We also compared carotenoid levels between environments that were either polluted by heavy metals or were not polluted, because the carotenoid-based plumage color of P. major nestlings is affected by environmental pollution. Lepidopterans were the most carotenoid-rich food items and contained the largest proportion of lutein. There were no differences in carotenoid concentrations in the food items of the two bird species but P. major nestlings obtained more carotenoids from their invertebrate diet than F. hypoleuca nestlings because the P. major diet had a higher proportion of lepidopteran larvae. In polluted areas, P. major nestlings consumed lower levels of dietary carotenoids than in unpolluted areas because of temporal differences in caterpillar abundance between polluted and unpolluted sites. Our study suggests that pollution-related difference in nestling plumage color in P. major is related to varying dietary proportion of lutein-rich food items rather than pollution-related variation in insect carotenoid levels.  相似文献   
4.
In an experiment conducted to study the effects of product expectations on subjective usability ratings, participants (N = 36) read a positive or a negative product review for a novel mobile device before a usability test, while the control group read nothing. In the test, half of the users performed easy tasks, and the other half hard ones, with the device. A standard usability test procedure was utilized in which objective task performance measurements as well as subjective post-task and post-experiment usability questionnaires were deployed. The study revealed a surprisingly strong effect of positive expectations on subjective post-experiment ratings: the participants who had read the positive review gave the device significantly better post-experiment ratings than did the negative-prime and no-prime groups. This boosting effect of the positive prime held even in the hard task condition where the users failed in most of the tasks. This finding highlights the importance of understanding: (1) what kinds of product expectations participants bring with them to the test, (2) how well these expectations represent those of the intended user population, and (3) how the test situation itself influences and may bias these expectations.  相似文献   
5.
Moisture and mold problems in buildings contaminate also the furniture and other movable property. If cleaning of the contaminated furniture is neglected, it may continue to cause problems to the occupants even after the moisture-damage repairs. The aim of this study was to determine the effectiveness of high-efficiency ozone treatment in cleaning of the furniture from moisture-damaged buildings. In addition, the effectiveness of two cleaning methods was compared. Samples were vacuumed from the padded areas before and after the treatment. The microbial flora and concentrations in the dust sample were determined by quantitative cultivation and QPCR-methods. The immunotoxic potential of the dust samples was analyzed by measuring effects on cell viability and production of inflammatory mediators in vitro. Concentrations of viable microbes decreased significantly in most of the samples after cleaning. Cleaning with combined steam wash and ozonisation was more effective method than ozonising alone, but the difference was not statistically significant. Detection of fungal species with PCR showed a slight but nonsignificant decrease in concentrations after the cleaning. The immunotoxic potential of the collected dust decreased significantly in most of the samples. However, in a small subgroup of samples, increased concentrations of microbes and immunotoxicological activity were detected. This study shows that a transportable cleaning unit with high-efficiency ozonising is in most cases effective in decreasing the concentrations of viable microbes and immunotoxicological activity of the furniture dust. However, the method does not destroy or remove all fungal material present in the dust, as detected with QPCR analysis, and in some cases the cleaning procedure may increase the microbial concentrations and immunotoxicity of the dust.  相似文献   
6.
In most applications, parametric monitoring schemes are used to monitor the majority of industrial and nonindustrial processes in order to improve the quality of the outputs or services. However, parametric monitoring schemes are known to underperform when the normality assumption is not met or when there is not enough information about the symmetry or asymmetry nature of the process underlying distribution. Hence, in this paper, a new nonparametric Phase II Shewhart-type double-sampling (DS) monitoring scheme based on the precedence statistic is proposed in order to efficiently monitor quality processes when the underlying process distribution departs from normality. The performance is investigated using the average run length (ARL), standard deviation of the run length (SDRL), expected ARL (EARL) and expected average number of observations to signal (EANOS), and the average sample sizes (ASS) metrics. The latter metrics are computed using Monte Carlo simulation and exact formulae. In general, it is shown that the new DS precedence scheme outperforms the existing basic Shewhart precedence scheme with and without supplementary runs rules in many situations. A real-life illustrative example based on a filling process of milk bottles is provided to demonstrate the application and implementation of the new DS precedence monitoring scheme.  相似文献   
7.
Self-reinforced polylactide–polyglycolide (80/20) composite rods, 2 mm in diameter and 36 mm in length, were implanted into the dorsal subcutaneous tissue of 20 rabbits. Osteotomies of the distal femur were fixed with these rods (2 × 15 mm) in the rabbits. The follow-up times varied from 3 to 104 weeks. After sacrifice, three-point bending and shear tests and molecular weight measurements were performed for subcutaneously placed rods. Radiological, histological, microradiographic, oxytetracycline-fluorescence, and histomorphometrical studies of the osteotomized and intact control femora were performed. After 6 weeks the mechanical properties had decreased significantly, but osteotomies had healed uneventfully. The present investigation showed that the mechanical strength and fixation properties of SR-Polylactide–glycolide (80/20) rods are suitable for fixation of cancellous bone osteotomies in rabbits provided that the operative technique is correct. The present article is the first report on the application of these rods for fixation of cancellous bone osteotomies.  相似文献   
8.
The experiment was conducted to measure the effects of Camelina sativa expeller on the performance of broiler chickens and on the sensory quality and fatty acid composition of broiler meat. One‐day‐old broiler chickens were randomly allocated to the three dietary treatments which lasted 37 days. Experimental diets contained 0, 5 or 10% C. sativa expeller. Feed and water were offered ad libitum. The birds were weighed at the beginning, at 14 days and at the end of the trial at 37 days. Feed intake was recorded between weighings. C. sativa expeller reduced the growth of the birds linearly (P < 0.001). It also depressed their feed intake and feed conversion ratio during the starter phase (1–14 days). C. sativa did not cause any significant enlargement of the thyroid gland, nor were any liver lesions observed. Feeding of C. sativa significantly (P < 0.001) increased the omega‐3 fatty acid level in broiler meat. This was mainly due to an increase in α‐linolenic acid (18:3, n‐3). Feeding did not seem to have any adverse effect on the sensory quality of broiler meat. Meat from female broilers produced by feeding 5% C. sativa in the diet was significantly (P = 0.02) more tender than meat produced by feeding 10% C. sativa. Copyright © 2007 Society of Chemical Industry  相似文献   
9.
Transient receptor potential ankyrin 1 (TRPA1) is an ion channel mainly studied in sensory neurons where it mediates itch, pain and neurogenic inflammation. Recently, some nonneuronal cells have also been shown to express TRPA1 to support inflammatory responses. To address the role of TRPA1 in skin inflammation, we aimed to investigate TRPA1 expression in keratinocytes. HaCaT cells (a model of human keratinocytes) and skin biopses from wild-type and TRPA1 deficient mice were used in the studies. TRPA1 expression in nonstimulated keratinocytes was very low but significantly inducible by the proinflammatory cytokine tumor necrosis factor (TNF) in an nuclear factor kappa B (NF-κB), and mitogen-activated protein (MAP) kinase (p38 and c-Jun N-terminal kinase, JNK)-dependent manner. Interestingly, drugs widely used to treat skin inflammation, the calcineurin inhibitors tacrolimus and cyclosporine and the glucocorticoid dexamethasone, significantly decreased TRPA1 expression. Furthermore, pharmacological inhibition and genetic deletion of TRPA1 reduced the synthesis of TNF-induced monocyte chemoattractant protein 1 (MCP-1) in keratinocytes and mouse skin biopsies. In conclusion, these findings point to an inflammatory role for TRPA1 in keratinocytes and present TRPA1 as a potential drug target in inflammatory skin diseases.  相似文献   
10.
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