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151.
Dejan Reljic Joachim Jost Kirsten Dickau Ralf Kinscherf Gabriel Bonaterra Birgit Friedmann-Bette 《Journal of sports sciences》2015,33(5):437-448
Dietary intake, vitamin status and oxidative stress were evaluated in 17 elite male boxers. Ten of them frequently reduced body weight rapidly before competitions (Weight Loss Group) and 7 did not practice rapid weight loss (Control Group). Food record checklists, blood samples for determination of vitamin status and plasma glutathione levels were obtained during a week of weight maintenance, a pre-competition week and a post-competition week. The average dietary intakes in both groups were 33 ± 8 kcal·kg?1, 3.7 ± 1.1 g·kg?1 carbohydrates, 1.5 ± 0.4 g·kg?1 protein, 1.2 ± 0.4 g·kg?1 fat and 2.2 ± 1.0 L water per day (excluding pre-competition week in Weight Loss Group). Energy (18 ± 7 kcal·kg?1), carbohydrate (2.2 ± 0.8 g·kg?1), protein (0.8 ± 0.4 g·kg?1), fat (0.6 ± 0.3 g·kg?1) and water (1.6 ± 0.6 L) consumption (P-values <0.001) and intakes of most vitamins (P-values < 0.05) were significantly reduced during the pre-competition week in the Weight Loss Group. In both groups, the intakes of vitamins A, E and folate were below recommended values throughout the three periods; however, blood vitamin and plasma glutathione levels did not change significantly. Our findings indicate a low-caloric and low-carbohydrate diet in elite boxers, regardless of participating in rapid weight loss or not. Apparently, the pre-competitional malnutitrition in the Weight Loss Group did not induce alterations in the vitamin and glutathione status. 相似文献
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153.
The integration of Cyber-Physical Systems in the industrial domain has become indispensable for Industry 4.0. Unfortunately, as the interconnectivity among them increases, so do the opportunities for malicious users to target them. Hence, it is necessary to increase the security of these systems and their components. A wide range of security solutions (e.g., industrial Firewalls) are already an integral part of Industrial Automation Systems, however, these are deployed at strategical system locations and might not be capable of identifying intrusions that target specific elements of embedded industrial devices. Host Intrusion Detection Systems (Host IDS) are one security solution that allow to detect such type of intrusions, as they analyze information related to specific host devices. This contribution presents a feasible Host IDS architecture for embedded industrial devices. This architecture takes into consideration features and capabilities of Host IDS from the IT domain. It also considers system-, environmental- and device-specific properties from the industrial domain. These properties are presented in the form of abstracted requirements and considerations that are contemplated for the conceptualization of the presented architecture. Furthermore, the feasibility of this architecture is validated through the implementation and evaluation of a prototypical Host IDS deployed in a Programmable Logic Controller (PLC) hosting a Real-Time Operating System (RTOS). This evaluation is achieved through the demonstration of a set of hypotheses derived from the abstracted requirements and supported by the evaluation of test scenarios. To the best of our knowledge, this is the first fully operational Host IDS to be deployed and evaluated on a PLC. 相似文献
154.
The impact of two types of written feedback (process-oriented, grade-oriented) on changes in mathematics achievement, interest and self-evaluation was compared – with a particular focus on the mediating role of feedback’s perceived usefulness. Participants, 146 ninth graders (aged 14 to 17?years), were assigned to either a process-oriented or a grade-oriented experimental feedback condition. They worked on mathematics tests, received feedback on their test results and completed surveys measuring feedback’s perceived usefulness, interest and self-evaluation. Results of path analysis showed that process-oriented feedback was perceived as more useful than grade-oriented feedback and that feedback’s perceived usefulness had a positive effect on changes in achievement and interest. Consistent with this, process-oriented feedback had a greater positive indirect effect than grade-oriented feedback on changes in mathematics achievement and interest via its perceived usefulness. There were no such effects on changes in self-evaluation. Potential explanations for these findings, educational implications and possible directions for future research are discussed. 相似文献
155.
Current literature about interdisciplinary education research is focused on three points: conceptual definitions of interdisciplinarity, the need for interdisciplinary research to tackle the advent of problem-based research and the positive curriculum outcomes to be gained from interdisciplinary research. While this research is important, it does not always include an account of the often complex and politicised interactions that might affect the outcomes of interdisciplinary research groups. This paper provides one possible ‘roadmap’ for successful interdisciplinary collaboration. It is based on a reflective case study of the authors’ own formation of an interdisciplinary research group and the practical resolutions to both the theoretical and the practical issues involved in achieving interdisciplinarity in education research. 相似文献