Unrestricted quality of seeds in European broad-leaved tree species growing at the cold boundary of their distribution.

BACKGROUND AND AIMS: The low-temperature range limit of tree species may be determined by their ability to produce and disperse viable seeds. Biological processes such as flowering, pollen transfer, pollen tube growth, fertilization, embryogenesis and seed maturation are expected to be affected by cold temperatures. The aim of this study was to assess the quality of seeds of nine broad-leaved tree species close to their elevational limit. METHODS: We studied nine, mostly widely distributed, European broad-leaved tree species in the genera Acer, Fagus, Fraxinus, Ilex, Laburnum, Quercus, Sorbus and Tilia. For each species, seeds were collected from stands close to optimal growth conditions (low elevation) and from marginal stands (highest elevation), replicated in two regions in the Swiss Alps. Measurements included seed weight, seed size, storage tissue quality, seed viability and germination success. KEY RESULTS: All species examined produced a lot of viable seeds at their current high-elevation range limit during a summer ranked 'normal' by long-term temperature records. Low- and high-elevation seed sources showed hardly any trait differences. The concentration of non-structural carbohydrates tended to be higher at high elevation. Additionally, in one species, Sorbus aucuparia, all measured traits showed significantly higher seed quality in high-elevation seed sources. CONCLUSIONS: For the broad-leaved tree taxa studied, the results are not in agreement with the hypothesis of reduced quality of seeds in trees at their high-elevation range limits. Under the current climatic conditions, seed quality does not constitute a serious constraint in the reproduction of these broad-leaved tree species at their high-elevation limit.

A medicolegal curriculum for internal medicine residents.

Many residents lack knowledge about medicolegal issues. To assess the ability of 64 primary care residents to learn legal medicine, we studied the impact of a medicolegal curriculum in a randomized, controlled study. We measured residents' medicolegal knowledge using a novel test, the Legal Medicine Evaluation (LME). We found that the mean LME score of residents exposed to the curriculum increased 15.5 points (on a 100-point scale) to 65.9 ( p <.01), while the mean LME score of control residents increased only 3.5 points, to 53.5 ( p =. 05). Clearly, residents can learn basic medicolegal principles. Thus, observed deficiencies in medicolegal knowledge most likely arise from inadequate medicolegal instruction.

Medicolegal program for resident physicians.

Few residents are taught to cope with medical liability and the legal aspects of business and administrative issues in medicine. The need for this practical, postgraduate curriculum led to be a collaborative effort between Dr. Kollas and the State Society to create an educational guidebook and seminar series which offers practical postgraduate medicolegal curriculum to resident physicians across Pennsylvania.

AML bipolar arthroplasty for degenerative hip arthritis.

Primary total hip arthroplasty using an uncemented AML porous coated femoral component and a bipolar acetabular component was performed on 50 consecutive patients with degenerative arthritis. Of the 50 patients, 43 (48 hips) were available for review at 2 to 3 years follow up. The data obtained in this review suggest that total hip arthroplasty using this prosthesis provides a consistently reliable hip replacement with few related complications and a high patient satisfaction rate. A stable radiographic appearance of both the femoral and acetabular components can be expected.