东亚地区二氧化碳体积分数变化特征

利用2004年以来东亚地区10个本底观测站大气φ(CO₂)观测资料,分析了各站大气φ(CO₂)的变化特征及其各站之间的差异,讨论了下垫面特征、源汇作用等对φ(CO₂)变化的影响.结果表明:10个本底站大气月均φ(CO₂)有明显的季节变化,高值多出现在冬春等寒冷季节,而低值则多出现在6—9月,属于北半球的夏季;大气φ(CO₂)日变化趋势较为一致,15时(当地时间)前后达到全天最低,随后φ(CO₂)升高,并在日落后继续积累,至清晨7时(当地时间)前后达到全天最高,之后φ(CO₂)随着太阳辐射的增强而逐渐降低,且平均φ(CO₂)水平与下垫面植被量成反比,φ(CO₂)日变化的幅度与下垫面植被量成反比.作为全球基准站之一的瓦里关山站,2004—2008年φ(CO₂)年均值逐年增加,年增长率为2.28×10^-6/a.     

An empirical evaluation of multi-media based learning of a procedural task

The present study investigated the effects of multi-media modules and their combinations on the learning of procedural tasks. In the experiment, 72 participants were classified as having either low- or high spatial ability based on their spatial ability test. They were randomly assigned to one of the six experimental conditions in a 2 × 3 factorial design with verbal modality (on-screen text procedure vs. auditory procedure) and the format of visual representation (static visual representation vs. static visual representation with motion cues vs. animated visual representation). After they completed their learning session, the ability to perform the procedural task was directly measured in a realistic setting. The results revealed that: (1) in the condition of static visual representation, the high spatial ability group outperformed the low spatial ability group, (2) for the low spatial ability participants, the animated visual representation group outperformed the static visual representation group, however, the static visual representation with motion cues group did not outperform the static visual representation group, (3) the use of animated visual representation helped participants with low spatial ability more than those with high spatial ability, and (4) a modality effect was found for the measure of satisfaction when viewing the animated visual representation. Since the participants with low spatial ability benefited from the use of animation, the results might support an idea that people are better able to retrieve the procedural information by viewing animated representation. The findings also might reflect a preference for the auditory mode of presentation with greater familiarity with the type of visual representation.     

Recovery of online service: Perceived justice and transaction frequency

Recovery of online service is an issue in need of study. The current study empirically examines (1) the relationships among perceived justice, satisfaction with recovery of online service and repurchase intention of online service/failure encounters; and (2) the moderating effects of transaction frequency on these relationships. The current study collects 187 self-administered questionnaires to gather customers’ perceptions of actual online service/failure encounters. Research findings demonstrate that distributive justice, interactional justice and procedural justice can positively lead to satisfaction with recovery of online service and repurchase intention toward online service. These results further show that customers with low transaction frequency tend to focus more on interactional justice to establish their satisfaction with recovery of online service. On the other hand, customers with high transaction frequency focus more on procedural justice.     

气候因素对城市色彩的影响分析

明确了城市色彩和城市色彩规划的概念,对气候影响城市色彩进行了分析.根据城市色彩的分类,分别分析气候因素对城市自然色以及人工色的不同影响.在分析人工色时,采用了"城市色彩三要素"的概念,即城市色彩的物理属性、构成性以及材质三要素,对这三个要素分别进行了气候影响力的分析.并针对当前温室效应的热点问题,指出城市色彩对城市气温的影响,以及如何利用城市色彩来达到减轻温室效应的目的.最后简要提出了城市色彩规划的一些应用原则.     

Phytoplankton biomass and primary production dynamics in Lake Kariba

The present study examined spatial, seasonal and depth variations in phytoplankton biomass and primary production (PP), compared with those reported for other tropical African lakes, to determine whether or not measured phytoplankton changes might be linked to climate warming. The biomass of three major phytoplankton classes (Cyanophyceae; Chlorophyceae; Bacillariophyceae) and net PP were measured during the midwinter and midsummer at six different depths at 35 sampling sites distributed across the lake’s five basins. A more rigorous sampling regime was used in the fifth basin, with phytoplankton biomass and PP rates measured every second month over a 24 month period at six different depths at ten sampling sites located in riverine and lacustrine waters. Cyanophyceae, which displayed a gradient of decreasing biomass from Basins 2 to 5, contributed 69% of the total phytoplankton biomass in the lake’s five basins during summer. This percentage was approximately four times greater than that contributed by the Bacillariophyceae and about ten times greater than that contributed by the Chlorophyceae. During winter, Bacillariophyceae biomass was equivalent to that of the Cyanophyceae, but displayed an opposing gradient of increasing biomass from Basins 1 to 3, with a subsequent biomass decline from Basins 3 to 5. Chlorophyceae exhibited no distinct biomass gradient across the five lake basins, being undetectable during winter. The biomass of all three phytoplankton classes and the net PP varied in magnitude and direction monthly between the lacustrine and riverine waters, with increasing water depth and with no distinct seasonal patterns being evident. The monthly variations in biomass were related to the thermal stratification cycle, hydrological gradients and the extent of water mixing, being similar to those reported for other tropical African lakes. It is noteworthy that total phytoplankton biomass and PP in Lake Kariba have declined by about 95% and 50%, respectively, since the 1980s. These declines correspond to an upward shift in the depth of the thermocline, associated with an average temperature increase of 1.9 °C and a 50% reduction in the depth of the euphotic zone, since the 1960s.     

ENVIRONMENTAL DETERMINANTS OF WATER QUALITY IN BOREAL RIVERS BASED ON PARTITIONING METHODS

Quantitative studies of the relationships between river water quality and environmental variables are needed to improve understanding of the impacts of natural and human factors on aquatic environments. However, multicollinearity between environmental variables can hinder the identification of key factors when water quality–environment relationship is studied using traditional regression methods. This study utilized two alternative statistical methods, variation and hierarchical partitioning, to address these difficulties in studies of river water quality. Using these methods, we explored the effects of catchment physiography, climate and land use variables on total phosphorus and nitrogen, pH, water colour and dissolved oxygen during the years 1995–2005 in 32 boreal rivers in Finland. Catchment physiography and land use explained most of the variation in water quality, especially in phosphorus, nitrogen and water colour data. The strong correlations (r_s > 0.8) between agricultural land use and phosphorus and nitrogen concentrations indicate that water quality is highly affected by agriculture in boreal regions. By determining the environmental drivers of different water quality variables, we can estimate the water quality of different catchments in response to environmental changes and identify areas that are sensitive to global changes. Our study shows that novel statistical methods integrated with geographic information system data and techniques provide deeper insights into water quality–environment relationships than traditional regression, and these should be considered when developing, for example, conservation planning for rivers. Copyright © 2011 John Wiley & Sons, Ltd.     

试析教师的精气神

教师生理上的精、气、神是教学上的精、气、神之根本动力,也是教学创新的核心,能起到事半功倍的作用。教师要想收获精彩的人生,做一个称职的教师,就必须在教学上拥有精、气、神。     

浅论社会公正的重要性及其实现方法

社会公正是我们永恒追求的理想,对我们极其重要。概括起来说其作用如下:是巩固中国共产党执政地位的需要,是社会主义的本质要求,是整个社会价值体系的首要价值,是经济发展的推动力,是社会稳定的基础,是凝聚力量的源泉。但目前社会不公的现象屡见不鲜,形势比较严竣,要扭转这种局面,我们应该从切实实现司法公正、优化财政支出结构、解决三农问题、维护市场经济秩序、完善社会保障制度等几个方面着手。     

WTO争端解决机制之价值取向

WTO争端解决机制作为一种程序性的制度，效率必然成为其所追求的价值之一。价值既体现在《争端解决程序与规则谅解》的条文中，且实践确立的“司法经济原则”更将效率价值发挥得淋漓尽致。此外，公平价值作为效率价值的衡平，为WTO争端解决机制追求法治奠定了基础，这对我国的法制建设提出新的挑战。     

Linking Organizational Resources and Work Engagement to Employee Performance and Customer Loyalty: The Mediation of Service Climate.

This study examined the mediating role of service climate in the prediction of employee performance and customer loyalty. Contact employees (N=342) from 114 service units (58 hotel front desks and 56 restaurants) provided information about organizational resources, engagement, and service climate. Furthermore, customers (N=1,140) from these units provided information on employee performance and customer loyalty. Structural equation modeling analyses were consistent with a full mediation model in which organizational resources and work engagement predict service climate, which in turn predicts employee performance and then customer loyalty. Further analyses revealed a potential reciprocal effect between service climate and customer loyalty. Implications of the study are discussed, together with limitations and suggestions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)