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11.
Producing polymeric or hybrid microfluidic devices operating at high temperatures with reduced or no water evaporation is a challenge for many on-chip applications including polymerase chain reaction (PCR). We study sample evaporation in polymeric and hybrid devices, realized by glass microchannels for avoiding water diffusion toward the elastomer used for chip fabrication. The method dramatically reduces water evaporation in PCR devices that are found to exhibit optimal stability and effective operation under oscillating-flow. This approach maintains the flexibility, ease of fabrication, and low cost of disposable chips, and can be extended to other high-temperature microfluidic biochemical reactors.  相似文献   
12.
This paper presents the optimal filtering and parameter identification problem for linear stochastic systems over linear observations with unknown parameters, where the unknown parameters are considered Wiener processes. The original problem is reduced to the filtering problem for an extended state vector that incorporates parameters as additional states. The resulting filtering system is bilinear in state and linear in observations. The obtained optimal filter for the extended state vector also serves as the optimal identifier for the unknown parameters. Performance of the designed optimal state filter and parameter identifier is verified for both, positive and negative, parameter values.  相似文献   
13.
Interviews were conducted with 336 mother-child dyads (children's ages ranged from 6 to 17 years; mothers' ages ranged from 20 to 59 years) in China, India, Italy, Kenya, the Philippines, and Thailand to examine whether normativeness of physical discipline moderates the link between mothers' use of physical discipline and children's adjustment. Multilevel regression analyses revealed that physical discipline was less strongly associated with adverse child outcomes in conditions of greater perceived normativeness, but physical discipline was also associated with more adverse outcomes regardless of its perceived normativeness. Countries with the lowest use of physical discipline showed the strongest association between mothers' use and children's behavior problems, but in all countries higher use of physical discipline was associated with more aggression and anxiety.  相似文献   
14.
In 2011 we, a group of English-as-a-foreign-language teachers at a secondary school in Argentina, decided to investigate our teaching practices through collaborative action research so as to improve our students’ learning opportunities and thus revitalise English-language teaching in our context. We implemented and evaluated the integration of content and language learning in our classrooms through the development of our own materials. The experience revealed a growth in professional development and how our motivation and autonomy influenced our students’ motivation and language development. In our attempt to disseminate our experience as a group, this report particularly focuses on the evaluation facets of our collaborative action research project so as to encourage other teachers and teacher-researchers to adopt collaborative action research to improve their own practices.  相似文献   
15.
This paper presents the optimal quadratic-Gaussian controller for uncertain stochastic polynomial systems with linear control input and a quadratic criterion over linear observations. The optimal closed-form controller equations are obtained using the separation principle, whose applicability to the considered problem is substantiated. As intermediate results, the paper gives closed-form solutions of the optimal regulator and controller problems for stochastic polynomial systems with linear control input and a quadratic criterion. Performance of the obtained optimal controller is verified in the illustrative example against the conventional quadratic-Gaussian controller that is optimal for stochastic polynomial systems with known parameters. Simulation graphs demonstrating overall performance and computational accuracy of the designed optimal controller are included.  相似文献   
16.
The aim of this study was to examine the contribution of school-related parental monitoring (SR-PM), self-determined motivation, and academic self-efficacy to academic achievement across time. The authors hypothesized that SR-PM would affect academic achievement indirectly via its effects on self-determined motivation and academic self-efficacy beliefs. The participants were 501 adolescents (220 boys; 281 girls) in Grades 6 and 9 as well as their mothers and fathers. We carried out a 2-year, multi-informant study in which the authors assessed SR-PM (maternal and paternal reports), self-determined motivation and academic self-efficacy (self-report), and academic achievement (school records). The authors used structural equation model analysis to test the hypotheses. The analysis shows that SR-PM was positively associated with self-determined motivation and academic self-efficacy and that self-determined motivation and academic self-efficacy affected academic achievement. Furthermore, analyses of indirect effects showed that SR-PM influences academic achievement via its effects on self-determined motivation and academic self-efficacy.  相似文献   
17.
This paper overviews the diverse information technologies that are used to provide athletes with relevant feedback. Examples taken from various sports are used to illustrate selected applications of technology-based feedback. Several feedback systems are discussed, including vision, audition and proprioception. Each technology described here is based on the assumption that feedback would eventually enhance skill acquisition and sport performance and, as such, its usefulness to athletes and coaches in training is critically evaluated.  相似文献   
18.
Modern public transportation companies often record large amounts of information. Privacy can be safeguarded by discarding nominal tickets, or introducing anonymization techniques. But is anonymity at all possible when everything is recorded? In this paper we discuss travel information management in the public transport scenario and we present a revealing case study (relative to the city of Cesena, Italy), showing that even anonymous 10-ride bus tickets may betray a user's privacy expectations. We also propose a number of recommendations for the design and management of public transport information systems, aimed at preserving the users’ privacy, while retaining the useful analysis features enabled by the e-ticketing technology.  相似文献   
19.
In this study, we used tensiomyography (TMG) to assess muscle status immediately after an ultra-endurance triathlon. Maximal radial displacement or deformation of the muscle belly, contraction time, delay time, sustain time, and relaxation time were measured for both legs, and dependent t-tests were used to compare means between the beginning and end of the race. The 19 men assessed (age 37.9 ± 7.1 years; height 177.5 ± 4.6 cm; weight: 73.6 ± 6.5 kg) participated in the 2009 edition of the Lanzarote Ironman. Deterioration in the neural response was observed for contraction time (P = 0.008) and relaxation time (P = 0.011), with a moderate decrease in the response time (sustain time) and a loss in muscle stiffness (deformation of the muscle belly). The effect of muscle fatigue on the rectus femoris and biceps femoris was different. Barely any changes in contraction time, relaxation time, sustain time, and deformation of the muscle belly were observed, while only the contraction response time decreased to a significant extent (reduction in delay time; P = 0.003). The considerable loss in contractile capacity induced by a long-distance race was reflected in changes in the neuromuscular response and fluctuations in the contractile capacity of the muscle. These modifications, derived from a prolonged, exhausting effort, can be assessed in a simple, non-aggressive, non-invasive way using tensiomyography.  相似文献   
20.
This study investigated how the age of entry into regular group day care may influence, in the context of other relevant variables, some short-time outcomes of this experience. In particular the study focused on behaviours expressing well-being or discomfort in the day care environment during the third year. Subjects were 129 young children who were enrolled in group day care when they were 6–29 months old. During their third year their social behaviour was evaluated by caregivers with the Day Care Adaptation Scale. Researchers observed 54 of the children in reunion with their parents. The quality of care was rated with the ITERS scale. It was found that children who started day care in the intervals 6–12 months and 18–23 months displayed more frequently difficult reunions with their mothers, and were rated as less resistant to frustration. Children who started day care from 12–17 months showed lower relational distress. Some significant relationships were found between the ratings of ITERS and the Day Care Adaptation Scale. These findings are discussed with reference to theories of attachment.  相似文献   
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