The effects of sodium bicarbonate (NaHCO3) ingestion on high intensity cycling capacity

Abstract

Ten healthy, non-cycling trained males (age: 21.2 ± 2.2 years, body mass: 75.9 ± 13.4 kg, height: 178 ± 6 cm, [Vdot]O_2PEAK: 46 ± 10 ml · kg^?1 · min^?1) performed a graded incremental exercise test, two familiarisation trials and six experimental trials. Experimental trials consisted of cycling to volitional exhaustion at 100%, 110% and 120% W_PEAK, 60 min after ingesting either 0.3 g · kg^?1 body mass sodium bicarbonate (NaHCO₃) or 0.1 g · kg^?1 body mass sodium chloride (placebo). NaHCO₃ ingestion increased cycling capacity by 17% at 100% W_PEAK (327 vs. 383 s; P = 0.02) although not at 110% W_PEAK (249 vs. 254 s; P = 0.66) or 120% W_PEAK (170 vs. 175 s; P = 0.60; placebo and NaHCO₃ respectively). Heart rate (P = 0.02), blood lactate (P = 0.001), pH (P < 0.001), [HCO₃ ^?], (P < 0.001), and base excess (P < 0.001) were greater in all NaHCO₃ trials. NaHCO₃ attenuated localised ratings of perceived exertion (RPE_L) to a greater extent than placebo only at 100% W_PEAK (P < 0.02). Ratings of abdominal discomfort and gut fullness were mild but higher for NaHCO₃. NaHCO₃ ingestion significantly improves continuous constant load cycling at 100% W_PEAK due to, in part, attenuation of RPE_L.     

数字技术支持的教师学习:研究与项目综述(上)

本文在系统回顾教师知识与教师学习本质的基础上,讨论了数字技术与教师学习活动之间的关系,主张将数字技术的效用描述为教师学习中有目的的一组活动,即：知识建构、分布式认知、社群与沟通以及约定,通过对五个技术支持的教师学习的典型案例。分析了数字技术对教师学习的支持作用。最后指出了数字技术支持的教师学习与专业发展之方向。     

Integrating Background Nursing Experience and Study at the Postgraduate Level: An Application of Problem Based Learning

The delivery of postgraduate courses to registered nurses is faced with the challenge of providing learning opportunities which accommodate a wide range of backgrounds and which draw upon the students' clinical experiences as well as upon conventional academic sources. Courses not providing such opportunities may be devalued by the students and perceived by them as removed from, and irrelevant to, clinical practice.

This paper describes a course which appears to have been successful both in providing for background diversity and in securing the integration of academic content and the clinical experiences of postgraduate nursing students. The course uses a problem based learning approach to cover concepts and principles relating to patient education and aspects of clinical teaching. The rationale of the approach and an outline of its features are provided.

The procedures used to evaluate the course are also described. The qualitative and quantitative data realised by these procedures indicate that the course was perceived by the students to be stimulating, interesting and consonant with their clinical needs and aspirations. The data also show that the main cognitive objective of the course was achieved by a substantial proportion of the students but that students would benefit from receiving more assistance with their learning skills.

It is concluded that the form of problem based learning used in the course can provide for the postgraduate educational needs of nurses from diverse professional and academic backgrounds.     

The effects of room design on computer-supported collaborative learning in a multi-touch classroom

While research indicates that technology can be useful for supporting learning and collaboration, there is still relatively little uptake or widespread implementation of these technologies in classrooms. In this paper, we explore one aspect of the development of a multi-touch classroom, looking at two different designs of the classroom environment to explore how classroom layout may influence group interaction and learning. Three classes of students working in groups of four were taught in the traditional forward-facing room condition, while three classes worked in a centered room condition. Our results indicate that while the outcomes on tasks were similar across conditions, groups engaged in more talk (but not more off-task talk) in a centered room layout, than in a traditional forward-facing room. These results suggest that the use of technology in the classroom may be influenced by the location of the technology, both in terms of the learning outcomes and the interaction behaviors of students. The findings highlight the importance of considering the learning environment when designing technology to support learning, and ensuring that integration of technology into formal learning environments is done with attention to how the technology may disrupt, or contribute to, the classroom interaction practices.