冠心病人康复训练后有氧工作能力和心肌供氧的变化

目的：探讨康复训练后冠心病人进行定量负荷运动时有氧工作能力和心肌供氧的变化，以此为康复效果的评估提供依据。方法：25名男性冠心病人参加了12周有氧多样化运动康复训练，训练前、后对他们在递增负荷运动中的生理和临床指标进行了测定。结果：1）反映冠脉血流和心肌耗氧量的指标RPP，康复训练前在跑台的V级负荷时已超过200，康复训练后增加幅度则有显著下降（P〈0．01）；2）康复训练前受试者的血乳酸浓度（BL）在Ⅳ级运动负荷之后出现了突增（达到4．6mmol／L），而康复训练后他们运动中的BL增加平缓，始终保持较低水平；3）康复训练前在V级运动负荷时受试者的ST下降达到-0．9mm水平，这已接近心肌缺血的阈值，训练后心肌供血出现了明显的改善。结论：康复训练前冠心病人运动中反映运动系统缺氧的BL突增领先于心肌缺血阈值的到达；与康复训练前相比，康复训练后冠心病人在进行相同负荷运动时显示出有氧工作能力有所增强，心肌供氧状况有所改善。     

Field-based teacher education in literacy: preparing teachers in real classroom contexts

For the past two decades, scholars have advocated for reforms in teacher education that emphasize relevant connections between theory and practice in university coursework and focus on clinical experiences. This paper is based on our experiences in designing and implementing an integrated literacy methods course in a field-based teacher education program. We describe issues involved in helping preservice teachers learn to differentiate literacy instruction for diverse learners in urban schools and describe how we use Grossman’s framework of representation, decomposition, and approximation of practice to connect theory and practice. We offer insights about the importance of using recursive cycles of practice and carefully scaffolded learning through attention to different aspects of practice. Initial successes and challenges in implementing field-based literacy education are discussed.     

The impact of library services in primary care trusts in NHS North West England: a large‐scale retrospective quantitative study of online resource usage in relation to types of service

Background: Within NHS North West England there are 24 primary care trusts (PCTs), all with access to different types of library services. This study aims to evaluate the impact the type of library service has on online resource usage. Methodology: We conducted a large‐scale retrospective quantitative study across all PCT staff in NHS NW England using Athens sessions log data. We studied the Athens log usage of 30 381 staff, with 8273 active Athens accounts and 100 599 sessions from 1 January 2007 to 31 December 2007. Results: In 2007, PCTs with outreach librarians achieved 43% penetration of staff with active Athens accounts compared with PCTs with their own library service (28.23%); PCTs with service level agreements (SLAs) with acute hospital library services (22.5%) and with no library service (19.68%). This pattern was also observed when we looked at the average number of Athens user sessions per person, and usage of Dialog Datastar databases and Proquest full text journal collections. Discussion: Our findings have shown a correlation of e‐resource usage and type of library service. Outreach librarians have proved to be an efficient model for promoting and driving up resources usage. PCTs with no library service have shown the lowest level of resource usage.     

Adolescent drug use and the deterrent effect of school-imposed penalties

Estimates of the effect of school-imposed penalties for drug use on a student's consumption of marijuana are biased if both are determined by unobservable school or individual attributes. Reverse causality is also a potential challenge to retrieving estimates of the causal relationship, as the severity of school sanctions may simply reflect the need for more-severe sanctions. Using the National Longitudinal Study of Adolescent Health, I offer an instrumental-variables approach to retrieving an estimate of the causal response of marijuana use to sanctions and thereby demonstrate the efficacy of school-imposed penalties as a deterrent to adolescent drug use. This suggests that school sanctions may have important long-run benefits.