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Author (up) Baselli, G.; Contreras, F.; Lillo, M.; Marin, M.; Carrasco, R.A. doi  openurl
  Title Optimal decisions for salvage logging after wildfires Type
  Year 2020 Publication Omega-International Journal Of Management Science Abbreviated Journal Omega-Int. J. Manage. Sci.  
  Volume 96 Issue Pages 9 pp  
  Keywords Salvage logging; Forest harvesting; Wildfires; Workforce allocation  
  Abstract Strategic, tactical, and operational harvesting plans for the forestry and logging industry have been widely studied for more than 60 years. Many different settings and specific constraints due to legal, environmental, and operational requirements have been modeled, improving the performance of the harvesting process significantly. During the summer of 2017, Chile suffered from the most massive wildfires in its history, affecting almost half a million hectares, of which nearly half were forests owned by medium and small forestry companies. Some of the stands were burned by intense crown fires, which always spread fast, that burned the foliage and outer layer of the bark but left standing dead trees that could be salvage harvested before insect and decay processes rendered them unusable for commercial purposes. Unlike the typical operational programming models studied in the past, in this setting, companies can make insurance claims on part or all of the burnt forest, whereas the rest of the forest needs to be harvested before it loses its value. This problem is known as the salvage logging problem. The issue also has an important social component when considering medium and small forestry and logging companies: most of their personnel come from local communities, which have already been affected by the fires. Harvesting part of the remaining forest can allow them to keep their jobs longer and, hopefully, leave the company in a better financial situation if the harvesting areas are correctly selected. In this work, we present a novel mixed-integer optimization-based approach to support salvage logging decisions, which helps in the configuration of an operational-level harvesting and workforce assignment plan. Our model takes into account the payment from an insurance claim as well as future income from harvesting the remaining trees. The model also computes an optimal assignment of personnel to the different activities required. The objective is to improve the cash position of the company by the end of the harvest and ensure that the company is paying all its liabilities and maintaining personnel. We show how our model performs compared to the current decisions made by medium and small-sized forestry companies, and we study the specific case of a small forestry company located in Cauquenes, Chile, which used our model to decide its course of action. (C) 2019 Elsevier Ltd. All rights reserved.  
  Address [Baselli, Gianluca; Contreras, Felipe; Lillo, Matias; Marin, Magdalena; Carrasco, Rodrigo A.] Univ Adolfo Ibanez, Fac Engn & Sci, Santiago, Chile, Email: gbaselli@alumnos.uai.cl;  
  Corporate Author Thesis  
  Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0305-0483 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000541944700003 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 1186  
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Author (up) Marin, M.; Perez-Pantoja, D.; Donoso, R.; Wray, V.; Gonzalez, B.; Pieper, D.H. pdf  doi
openurl 
  Title Modified 3-Oxoadipate Pathway for the Biodegradation of Methylaromatics in Pseudomonas reinekei MT1 Type
  Year 2010 Publication Journal Of Bacteriology Abbreviated Journal J. Bacteriol.  
  Volume 192 Issue 6 Pages 1543-1552  
  Keywords  
  Abstract Catechols are central intermediates in the metabolism of aromatic compounds. Degradation of 4-methyl-catechol via intradiol cleavage usually leads to the formation of 4-methylmuconolactone (4-ML) as a dead-end metabolite. Only a few microorganisms are known to mineralize 4-ML. The mml gene cluster of Pseudomonas reinekei MT1, which encodes enzymes involved in the metabolism of 4-ML, is shown here to encode 10 genes found in a 9.4-kb chromosomal region. Reverse transcription assays revealed that these genes form a single operon, where their expression is controlled by two promoters. Promoter fusion assays identified 4-methyl-3-oxoadipate as an inducer. Mineralization of 4-ML is initiated by the 4-methylmuconolactone methylisomerase encoded by mmlI. This reaction produces 3-ML and is followed by a rearrangement of the double bond catalyzed by the methylmuconolactone isomerase encoded by mmlJ. Deletion of mmlL, encoding a protein of the metallo-beta-lactamase superfamily, resulted in a loss of the capability of the strain MT1 to open the lactone ring, suggesting its function as a 4-methyl-3-oxoadipate enol-lactone hydrolase. Further metabolism can be assumed to occur by analogy with reactions known from the 3-oxoadipate pathway. mmlF and mmlG probably encode a 4-methyl-3-oxoadipyl-coenzyme A (CoA) transferase, and the mmlC gene product functions as a thiolase, transforming 4-methyl-3-oxoadipyl-CoA into methylsuccinyl-CoA and acetyl-CoA, as indicated by the accumulation of 4-methyl-3-oxoadipate in the respective deletion mutant. Accumulation of methylsuccinate by an mmlK deletion mutant indicates that the encoded acetyl-CoA hydrolase/transferase is crucial for channeling methylsuccinate into the central metabolism.  
  Address [Marin, Macarena; Pieper, Dietmar H.] Helmholtz Zentrum Infekt Forsch, Dept Microbial Pathogenesis, D-38124 Braunschweig, Germany, Email: dpi@helmholtz-hzi.de  
  Corporate Author Thesis  
  Publisher Amer Soc Microbiology Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9193 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000274891300009 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 84  
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