Remote sensing is revolutionizing the way we study forests, and recent technological advances mean we are now able -for the first time -to identify and measure the crown dimensions of individual trees from airborne imagery. Yet to make full use of these data for quantifying forest carbon stocks and dynamics, a new generation of allometric tools which have tree height and crown size at their centre are needed. Here, we compile a global database of 108753 trees for which stem diameter, height and crown diameter have all been measured, including 2395 trees harvested to measure aboveground biomass. Using this database, we develop general allometric models for estimating both the diameter and aboveground biomass of trees from attributes which can be remotely sensed -specifically height and crown diameter. We show that tree height and crown diameter jointly quantify the aboveground biomass of individual trees and find that a single equation predicts stem diameter from these two variables across the world's forests. These new Correspondence: Tommaso Jucker, tel. +44 1223 333911, fax: +44 1223 333953,

Twenty-eight principal dancers and soloists from America's two most famous ballet companies were examined for anthropometric measurements, including flexibility, muscle strength, and joint range of motion. Both male and female dancers were flexible, but not hypermobile, and did not differ significantly from each other. Marked differences were found between the range of motion of the hip and ankle in the dancers and the norms for the general population. The increased external rotation of the hip in women was accompanied by a loss in internal rotation, resulting in an increased range of motion with an externally rotated orientation. The men, however, lost more internal rotation than they gained in external rotation. These data raise the possibility of a torsional component to the turned-out hip position in elite female professional ballet dancers. In addition, significant anatomic differences separate elite dancers of both sexes from the normal population.

Twenty-nine soloist and principal dancers (mean age, 29.08 years) from America's two most celebrated ballet companies were administered questionnaires measuring personality (API), occupational stress (OES), strain (PSQ), and coping mechanisms (PRQ), and injury patterns. The results revealed that male dancers demonstrated significantly more negative personality traits and psychological distress than female dancers or men in the general population. In addition, physical stress and personality traits, characteristic of the "overachiever," distinguished injured dancers. It is suggested that classical ballet's emphasis on the ballerina may be at odds with a masculine identity in male dancers. Furthermore, the qualities that lead to success in this profession may contribute to injuries if carried to an extreme.

The increasing availability of highly detailed three-dimensional remotely-sensed data depicting forests, including airborne laser scanning (ALS) and digital aerial photogrammetric (DAP) approaches, provides a means for improving stand dynamics information. The availability of data from ALS and DAP has stimulated attempts to link these datasets with conventional forestry growth and yield models. In this study, we demonstrated an approach whereby two three-dimensional point cloud datasets (one from ALS and one from DAP), acquired over the same forest stands, at two points in time (circa 2008 and 2015), were used to derive forest inventory information. The area-based approach (ABA) was used to predict top height (H), basal area (BA), total volume (V), and stem density (N) for Time 1 and Time 2 (T1, T2). We assigned individual yield curves to 20 × 20 m grid cells for two scenarios. The first scenario used T1 estimates only (approach 1, single date), while the second scenario combined T1 and T2 estimates (approach 2, multi-date). Yield curves were matched by comparing the predicted cell-level attributes with a yield curve template database generated using an existing growth simulator. Results indicated that the yield curves using the multi-date data of approach 2 were matched with slightly higher accuracy; however, projections derived using approach 1 and 2 were not significantly different. The accuracy of curve matching was dependent on the ABA prediction error. The relative root mean squared error of curve matching in approach 2 for H, BA, V, and N, was 18.4, 11.5, 25.6, and 27.53% for observed (plot) data, and 13.2, 44.6, 50.4 and 112.3% for predicted data, respectively. The approach presented in this study provides additional detail on sub-stand level growth projections that enhances the information available to inform long-term, sustainable forest planning and management. less detailed information than single-tree or size-class models [2]. The choice of growth simulator depends on its availability for the area of interest-e.g., in Canada growth simulators have been developed for each province separately, with whole-stand models being popular in British Columbia and Alberta. In the majority of cases, the core set of input attributes for stand-level growth simulators includes species composition, stand age, and top height or alternatively site index. Additional inputs can improve model accuracy and can include information on stand density, basal area, stocking, canopy cover, information on insect damage, and silvicultural practices such as thinning or fertilization [3,4]. Simulator output typically consists of a list of predicted stand attributes for a specified age sequence (e.g., 10, 20, 30 years in the future), stratified by species. Stand attributes include top height, basal area, merchantable and total volume, and stand density.Airborne laser scanning (ALS) has demonstrated capacity for characterizing a number of important forest stand attributes [5,6]. Three-dimensional point clouds acquired with ALS preci...

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Resource development can have significant consequences for the distribution of vegetation cover and for species persistence. Modelling changes to anthropogenic disturbance regimes over time can provide profound insights into the mechanisms that drive land cover change. We analyzed the spatial patterns of anthropogenic disturbance before and after a period of significant oil and gas extraction in two boreal forest subregions in Alberta, Canada. A spatially explicit model was used to map levels of anthropogenic forest crown mortality across 700 000 ha of managed forest over a 60-year period. The anthropogenic disturbance regime varied both spatially and temporally and was outside the historical range of variability characterized by regional fire regimes. Levels of live forest crown within anthropogenic disturbances declined and edge density increased following oil and gas development, whereas patch size varied regionally. In some places, anthropogenic disturbance generated profoundly novel landscapes with spatial patterns that had no historical analogue in the boreal system. The results illustrate that a shift in one sector of the economy can have dramatic outcomes on landscape structure. The results also suggest that any efforts to better align cumulative anthropogenic disturbance patterns with the historic baseline will almost certainly require a concerted and collaborative effort from all of the major stakeholders.Résumé : L'exploitation des ressources peut avoir d'importantes conséquences sur la répartition du couvert végétal et la persistance des espèces. La modélisation des changements temporels dus aux régimes de perturbation anthropique peut déboucher sur une meilleure connaissance des mécanismes qui déterminent les modifications du couvert végétal. Nous avons analysé la configuration spatiale des perturbations anthropiques avant et après une période durant laquelle une quantité importante de pétrole et de gaz a été extraite dans deux forêts boréales en Alberta, au Canada. Un modèle spatialement explicite a été utilisé pour cartographier le niveau de mortalité d'origine anthropique dans le couvert forestier sur un territoire de forêt aménagée de 700 000 ha pendant une période de 60 ans. Le régime de perturbation anthropique a varié dans le temps et l'espace et excédait les limites historiques de variabilité caractérisées par des régimes de feu régionaux. Les niveaux de couvert forestier vivant dans les zones de perturbation anthropique ont diminué et la densité de lisière a augmenté à la suite de l'exploitation du pétrole et du gaz tandis que la dimension des parcelles de forêt variait selon la région. À certains endroits, les perturbations anthropiques ont engendré des paysages totalement nouveaux dont la configuration spatiale n'avait aucun équivalent dans l'histoire du système boréal. Les résultats illustrent le fait qu'un changement dans un secteur de l'économie peut avoir des effets dramatiques sur la structure du paysage. Les résultats indiquent aussi que toute tentative visant faire en sorte que la c...

Opioid Safety Initiative implementation was associated with a substantial reduction in high-dose opioid prescribing. Factors that contributed to initiative success included leadership support and active clinical pharmacy engagement.