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Programs have been developed that use a backpropagation neural network to automatically edit noisy seismic traces and pick first break refraction events. This paper shows that neural network-based trace editing and first break picking can achieve 85 to 98 percent agreement with manual methods for seismic data of moderate to good quality. Productivity improvements over current manual editing and picking techniques for 2D seismic data should range between 60 and 90 percent. For 3D seismic data sets efficiency increases of up to 800 percent have been demonstrated in a production processing environment. Nous avons développé des programmes utilisant les réseaux neuronaux et la rétropropagation pour l'édition automatique de traces bruitées et le pointé des premières arrivées. Cet article montre que les réseaux neuronaux peuvent donner des résultats en accord à 85-98% avec les méthodes manuelles d'édition de traces et de pointé des premières arrivées sur des données sismiques de qualité moyenne ou bonne. Les gains de productivité par rapport aux techniques manuelles actuelles d'édition et de pointé sur des données sismiques 2-D se situeraient de 60 à 90 %. Pour des jeux de données sismiques 3D, des gains de productivité allant jusqu'à 800 % ont été obtenus en production.

Plantar fasciitis is one of the most common causes of foot and heel pain in adults. Extracorporeal shockwave therapy (ESWT) and platelet-rich plasma (PRP) have each been described as effective treatments for plantar fasciitis; however, the combined use has not been adequately described. This report characterizes successful return to sport in two runners with plantar fasciitis who were treated with ESWT combined with PRP. Patient-reported outcomes were measured using the Foot and Ankle Ability Measure (FAAM). A 69-year-old female had 8 months of pain refractory to physical therapy (PT). A 73-year-old male presented with recent onset of 3 weeks of symptoms. Both runners had exam findings of plantar fasciitis and MRI confirmation. Each elected to complete ESWT along with PT using a foot core program and met functional improvements for both sport and ADL subscales of FAAM after initial ESWT treatment. However, each runner had worsening pain when attempting to run and both elected to proceed with a single leukocyte-poor PRP injection combined with ESWT. This allowed for successful return to running. Both cases highlight how combined ESWT and PRP with a foot core PT progression may be effective in managing plantar fasciitis in running athletes.Key Words: Regenerative Medicine, Running, Extracorporeal Shockwave Therapy (ESWT), Foot and Ankle Ability Measure (FAAM)

Vegetation impacts on ecosystem functioning are mediated by mycorrhizas, plant-fungal associations formed by most plant species. Ecosystems dominated by distinct mycorrhizal types differ strongly in their biogeochemistry. Quantitative analyses of mycorrhizal impacts on ecosystem functioning are hindered by the scarcity of information on mycorrhizal distributions. Here we present global, high-resolution maps of vegetation biomass distribution by dominant mycorrhizal associations. Arbuscular, ectomycorrhizal, and ericoid mycorrhizal vegetation store, respectively, 241 ± 15, 100 ± 17, and 7 ± 1.8 GT carbon in aboveground biomass, whereas non-mycorrhizal vegetation stores 29 ± 5.5 GT carbon. Soil carbon stocks in both topsoil and subsoil are positively related to the community-level biomass fraction of ectomycorrhizal plants, though the strength of this relationship varies across biomes. We show that human-induced transformations of Earth's ecosystems have reduced ectomycorrhizal vegetation, with potential ramifications to terrestrial carbon stocks. Our work provides a benchmark for spatially explicit and globally quantitative assessments of mycorrhizal impacts on ecosystem functioning and biogeochemical cycling.

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Fine root lifespan is a critical trait associated with contrasting root strategies of resource acquisition and protection. Yet, its position within the multidimensional "root economics space" synthesizing global root economics strategies is largely uncertain, and it is rarely represented in frameworks integrating plant trait variations. Here, we compiled the most comprehensive dataset of absorptive median root lifespan (MRL) data including 98 observations from 79 woody species using (mini-) rhizotrons across 40 sites and linked MRL to other plant traits to address questions of the regulators of MRL at large spatial scales. We demonstrate that MRL not only decreases with plant investment in root nitrogen (associated with more metabolically active tissues) but also increases with construction of larger diameter roots which is often associated with greater plant reliance on mycorrhizal symbionts. Although theories linking organ structure and function suggest that root traits should play a role in modulating MRL, we found no correlation between root traits associated with structural defense (root tissue density and specific root length) and MRL. Moreover, fine root and leaf lifespan were globally unrelated, except among evergreen species, suggesting contrasting evolutionary selection between leaves and roots facing contrasting environmental influences above vs. belowground. At large geographic scales, MRL was typically longer at sites with lower mean annual temperature and higher mean annual precipitation. Overall, this synthesis uncovered several key ecophysiological covariates and environmental drivers of MRL, highlighting broad avenues for accurate parametrization of global biogeochemical models and the understanding of ecosystem response to global climate change. [ABSTRACT FROM AUTHOR]

The earth's future climate state is highly dependent upon changes in terrestrial C storage in response to rising concentrations of atmospheric CO₂. Here we show that consistently enhanced rates of net primary production (NPP) are sustained by a C-cascade through the root-microbe-soil system; increases in the flux of C belowground under elevated CO₂ stimulated microbial activity, accelerated the rate of soil organic matter decomposition and stimulated tree uptake of N bound to this SOM. This process set into motion a positive feedback maintaining greater C gain under elevated CO₂ as a result of increases in canopy N content and higher photosynthetic N-use efficiency. The ecosystem-level consequence of the enhanced requirement for N and the exchange of plant C for N belowground is the dominance of C storage in tree biomass but the preclusion of a large C sink in the soil.

1. Root respiration is essential for nutrient acquisition. The respiration rate of absorptive roots theoretically relates to the economics of carbon‐nutrient exchange, but its empirical role remains largely unexplored in the trait space defining nutrient uptake strategies. 2. Here, we measured the respiration rates of the distal, non‐woody, absorptive roots of 252 woody and herbaceous species from subtropical and temperate climate zones, including both arbuscular mycorrhizal and ectomycorrhizal fungal hosts. 3. We found a consistent and positive correlation between root respiration rate and specific root length (root length per dry weight), irrespective of growth form, mycorrhizal type and climate zone. Root respiration rate was also positively, but less strongly and less frequently correlated with root nitrogen concentration. Root morphology strongly explained the fast‐slow gradient of root respiration in the root economics space. 4. By quantifying the ratio of arbuscular mycorrhizal fungal DNA copy number and root tissue DNA copy number using qPCR, we found that the morphology‐driven gradient did not explain the full variation in fungal collaboration; thick roots were consistently well colonised, but medium and thin roots displayed a wide range of colonisation intensity. 5. Synthesis: These results advance our understanding of the fundamental trait relationships that underpin the root economics space. Our study also provides a physiological linkage to the frequently measured root morphological traits and relates the root economics space to root‐derived carbon‐nutrient cycling processes. [ABSTRACT FROM AUTHOR]