Litter carbon dynamics analysis in forests in an arid ecosystem with a model incorporating the physical removal of litter

金沢大学理工研究域自然システム学系Arid land afforestation could be a countermeasure for global warming, and a project for developing and evaluating techniques for arid land afforestation and reforestation has been carried out in Sturt Meadows near Leonora, Western Australia. As a part of this project, the litter carbon dynamics were investigated at three Acacia aneura forest sites, using a litter carbon model incorporating the physical removal of litter by winds, floods, etc. Based on the field observation data of above ground plant biomass, annual litter fall, existing amount of the litter, and also litter decomposition rate constants separately obtained for leaf litter and woody litter, we investigated the carbon flows at these forest sites, especially the annual amount of litter physically removed from the sites by floods or winds. As a result, it is estimated that annual physical removal of litter amounted to 59-75% of the annual litter fall, and the litter removal rate constants were from 0.38 to 0.55 year-1. Roughly one third to a half of the existing litter is removed annually from the sites. There was also a tendency that as the canopy coverage decreases, the litter removal rate constant increases. For this type of ecosystem, which is susceptible to the run-off of water and strong winds, we consider the taking into account of the physical removal of the litter is essential for analyzing the carbon dynamics in the ecosystem. © 2008 Elsevier B.V. All rights reserved

Long-term outcomes of an esophagus-preserving chemoradiotherapy strategy for patients with endoscopically unresectable stage I thoracic esophageal squamous cell carcinoma

[Background and purpose] To assess the long-term outcomes of a multimodal approach for maximum esophagus preservation in operable patients with endoscopically unresectable stage I thoracic esophageal squamous cell carcinoma (ESCC). [Materials and methods] The medical records of patients with stage I thoracic ESCC treated with our protocol between 1992 and 2005 were retrospectively reviewed. Our protocol consisted of neoadjuvant concurrent chemoradiotherapy, followed by either additional definitive chemoradiotherapy for good responders (CRT group) or surgery for moderate or poor responders (CRT-S group) after an interim appraisal. [Results] A total of 51 patients were analysed. The median age of the patients was 67 years. The median follow-up period was 124.8 months. After the interim assessment, 49 and 2 cases were assigned to the CRT and CRT-S groups, respectively. In the intent-to-treat analyses, overall survival (OS), disease-free survival (DFS), cumulative incidence for death from esophageal cancer, and that for loss of esophageal function were 78.9%, 53.5%, 10.5%, and 20.4% at 5 years, and 55.2%, 27.8%, 18.2%, and 22.9% at 10 years, respectively. Grade 3 late toxicities occurred with the following incidences: esophageal stenosis in 1 case, esophageal ulcer in 1 case, and pericardial effusion in 2 cases. No grade 4 or higher toxicities were observed. [Conclusion] Long-term survival and esophagus preservation outcomes were favorable, with acceptable toxicities. Our results suggest that CCRT is an alternative treatment for majority of operable patients with endoscopically unresectable stage I thoracic ESCC in combination with salvage therapy

Homogeneous Enantioselective Catalysis in a Continuous-Flow Microreactor: Highly Enantioselective Borohydride Reduction of Ketones Catalyzed by Optically Active Cobalt Complexes

Highly enantioselective homogeneous catalysis under continuous-flow conditions was established for the cobalt-catalyzed borohydride reduction of tetralone derivatives. A microreactor allowed higher reaction temperature with the residence time of 12 min than the corresponding batch system to maintain enantioselectivity as well as reactivity. The present system was directly applied to gram-scale synthesis to afford the reduced product with 92% ee