Role of land-surface changes in arctic summer warming.

A major challenge in predicting Earth's future climate state is to understand feedbacks that alter greenhouse-gas forcing. Here we synthesize field data from arctic Alaska, showing that terrestrial changes in summer albedo contribute substantially to recent high-latitude warming trends. Pronounced terrestrial summer warming in arctic Alaska correlates with a lengthening of the snow-free season that has increased atmospheric heating locally by about 3 watts per square meter per decade (similar in magnitude to the regional heating expected over multiple decades from a doubling of atmospheric CO2). The continuation of current trends in shrub and tree expansion could further amplify this atmospheric heating by two to seven times.

Functional assessment of repetitive strain injuries: two case studies.

More patients with repetitive strain injuries (RSIs) are being seen in occupational therapy clinics in Hong Kong. To reduce the incidence of work-related RSIs, it is necessary to identify problem jobs and/or specific tasks that are associated with an increased risk of these disorders. Physical assessment, videotaping, ergonomic evaluations, and analyses of workstation designs are used for this purpose. In Hong Kong, however, these methods cannot be implemented at the jobsite without the approval of the employer. This restriction constitutes a major problem in planning the rehabilitation of workers who have RSIs. A self-assessment method using the Work Evaluation Systems Technology (WEST) Tool Sort and the LLUMC Activity Sort was adopted as part of the evaluation of clients with RSIs. The questionnaires were translated into Chinese and reviewed and revised for content validity by ten occupational therapists. Two case studies are presented to illustrate the occupational therapy intervention program based on this self-report instrument. The questionnaires were found to be efficient and useful in assessing the client's abilities at work and in explaining to the client the relationship of his or her working conditions to the RSIs.