Evaluación de la vulnerabilidad de sistemas eléctricos por medio de programación multinivel: una revisión bibliográfica

Vulnerability studies can identify critical elements in electric power systems in order to take protective measures against possible scenarios that may result in load shedding, which can be caused by natural events or deliberate attacks. This article is a literature review on the latter kind, i.e., the interdiction problem, which assumes there is a disruptive agent whose objective is to maximize the damage to the system, while the network operator acts as a defensive agent. The non-simultaneous interaction of these two agents creates a multilevel optimization problem, and the literature has reported several interdiction models and solution methods to address it. The main contribution of this paper is presenting the considerations that should be taken into account to analyze, model, and solve the interdiction problem, including the most common solution techniques, applied methodologies, and future studies. This literature review found that most research in this area is focused on the analysis of transmission systems considering linear approximations of the network, and a few interdiction studies use an AC model of the network or directly treat distribution networks from a multilevel standpoint. Future challenges in this field include modeling and incorporating new defense options for the network operator, such as distributed generation, demand response, and the topological reconfiguration of the system.f the system.Los estudios de vulnerabilidad pueden identificar elementos críticos en los sistemas de distribución de potencia eléctrica con el fin de tomar medidas de protección contra posibles escenarios que pueden resultar en desconexión de carga (también llamado deslastre de carga), que puede ser ocasionada por eventos naturales o ataques deliberados. Este artículo es una reseña bibliográfica sobre el segundo tipo de casos, es decir, los del problema de interdicción, en el que se asume la existencia de un agente disruptivo cuyo objetivo es maximizar los daños ocasionados al sistema mientras el operador de red actúa como agente de defensa del mismo. La interacción no simultánea de estos dos agentes crea un problema de optimización multinivel y en la bibliografía se reportan varios modelos de interdicción y soluciones para abordar el problema. La contribución principal de este artículo es la presentación de consideraciones que deben tomarse en cuenta para analizar, modelar y resolver el problema de la interdicción, incluyendo las soluciones, métodos y técnicas más comunes para solucionarlo, así como futuros estudios al respecto. Esta revisión encontró que la mayoría de la investigación en el tema se enfoca en el análisis de los sistemas de transmisión, considerando las aproximaciones lineales de la red; algunos estudios en interdicción usan un modelo AC de la red o tratan las redes de distribución directamente desde un enfoque multinivel. Algunos retos en este campo son el modelado y la inclusión de nuevas opciones de defensa para el operador de la red, como la generación distribuida, la respuesta a la demanda y la reconfiguración topológica del sistema.&nbsp

¿Es viable un diseño de un sistema de iluminación tipo LED al túnel de acceso a casa de máquinas en la central hidroeléctrica la tasajera?

Diseñar un sistema de Iluminación tipo led en el túnel de acceso casa de máquinas de la central hidroeléctrica la Tasajera.La limitada disponibilidad de recursos energéticos no renovables y los crecientes problemas ambientales causados por la producción, distribución y consumo de la energía, conduce a realizar cambios en nuestros hábitos energéticos. Con el cambio del tipo de alumbrado por uno más eficiente se optimiza la mano de obra, se incrementan los niveles de luminosidad en el túnel, propiciando más seguridad para los vehículos y los peatones, se disminuye los materiales de consumo para las reparaciones, se disminuye el consumo de energía y por ende la rentabilidad del negocio, pegándole directamente a la MEGA de la Organización. Al disminuir el consumo de energía se deja de generar CO2 proporcionando más calidad ambiental

Neocordana gen. nov., the causal organism of Cordana leaf spot on banana

Cordana leaf spot of banana is shown to be associated with several species of a new genus described here as Neocordana gen. nov. Furthermore, Neocordana belongs to Pyriculariaceae (Magnaporthales) rather than Cordanaceae where the type species of Cordana, C. pauciseptata resides. Neocordana is established to accommodate Cordana musae, C. johnstonii, C. versicolor, and a previously undescribed species, N. musicola, which is morphologically and phylogenetically distinct. Neocordana species are found to be associated with leaves of Musa spp. (Musaceae) and Canna denudata (Cannaceae). Based on these results, Cordanaceae is best recognized in a separate order, established here as Cordanales ord. nov.http://www.mapress.com/phytotaxahb201

Taxonomic and phylogenetic re-evaluation of Microdochium, Monographella and Idriella

Based on morphology and DNA sequence data the taxonomic relationships of Microdochium, Mono­graphella and Idriella were reassessed. Microdochium is morphologically and phylogenetically circumscribed, and the sexual genus Monographella treated as synonym on the basis that Microdochium has more species, is more commonly encountered, and more frequently used in literature. An epitype is designated for Microdochium phragmites, and several well-known species are redefined based on their morphology and DNA sequence data (LSU, ITS, BTUB and RPB2). Furthermore, the revision of Microdochium led to six new combinations (M. albescens, M. consociatum, M. fusariisporum, M. maydis, M. opuntiae and M. stevensonii) and six new species (M. citrinidiscum, M. colombiense, M. fisheri, M. neoqueenslandicum, M. seminicola and M. trichocladiopsis) being proposed. Microdochium s.str. belongs to a monophyletic clade, together with Idriella lunata and Selenodriella, representing a new family, Microdochiaceae, in Xylariales. Other species previously accommodated in Microdochium belong to different orders in the Ascomycota. Microdochium gracile belongs to Sordariomycetes (incertae sedis) and Paramicrodochium is proposed to accommodate this species. Microdochium tripsaci belongs to Ephelis in Clavicipitaceae, while M. fusa­rioides belongs to a new genus, Microdochiella in Orbiliales. Idriella s.str. is a monotypic genus phylogenetically closely related to Microdochium. Idriella s.l. separates into different genera in Xylariales (incertae sedis) including Castanediella, Selenodriella, Idriellopsis, Neoidriella and Paraidriella, the last three proposed here as new genera.http://www.persoonia.orghttp://www.ingentaconnect.com/content/nhn/pimjhb201

Taxonomic and phylogenetic re-evaluation of Microdochium, Monographella and Idriella

Based on morphology and DNA sequence data the taxonomic relationships of Microdochium, Mono­graphella and Idriella were reassessed. Microdochium is morphologically and phylogenetically circumscribed, and the sexual genus Monographella treated as synonym on the basis that Microdochium has more species, is more commonly encountered, and more frequently used in literature. An epitype is designated for Microdochium phragmites, and several well-known species are redefined based on their morphology and DNA sequence data (LSU, ITS, BTUB and RPB2). Furthermore, the revision of Microdochium led to six new combinations (M. albescens, M. consociatum, M. fusariisporum, M. maydis, M. opuntiae and M. stevensonii) and six new species (M. citrinidiscum, M. colombiense, M. fisheri, M. neoqueenslandicum, M. seminicola and M. trichocladiopsis) being proposed. Microdochium s.str. belongs to a monophyletic clade, together with Idriella lunata and Selenodriella, representing a new family, Microdochiaceae, in Xylariales. Other species previously accommodated in Microdochium belong to different orders in the Ascomycota. Microdochium gracile belongs to Sordariomycetes (incertae sedis) and Paramicrodochium is proposed to accommodate this species. Microdochium tripsaci belongs to Ephelis in Clavicipitaceae, while M. fusa­rioides belongs to a new genus, Microdochiella in Orbiliales. Idriella s.str. is a monotypic genus phylogenetically closely related to Microdochium. Idriella s.l. separates into different genera in Xylariales (incertae sedis) including Castanediella, Selenodriella, Idriellopsis, Neoidriella and Paraidriella, the last three proposed here as new genera.http://www.persoonia.orghttp://www.ingentaconnect.com/content/nhn/pimjhb201

First characterization of toxic alkaloids and volatile organic compounds (VOCs) in the cryptic dendrobatid Silverstoneia punctiventris

Background: Poison frogs are known for the outstanding diversity of alkaloid-based chemical defences with promising therapeutic applications. However, current knowledge about chemical defences in Dendrobatoidea superfamily has two sources of bias. First, cryptic, brown-colored species have been neglected in comparison to those conspicuously colored, and second, there has been little interest in characterizing metabolites other than alkaloids mediating defensive functions. In an effort to contribute to fill the gap of knowledge about cryptic species and broadening the spectrum of compounds analyzed we have applied head-space solid phase microextraction coupled to gas chromatography and mass spectrometry (HS-SPME/GC-MS) for extracting amphibian alkaloids and volatile organic compounds (VOCs) from Silverstoneia punctiventris. Results: Using the skin from 8 specimens in 4 biological replicates we have found 33 different compounds. Twenty of them were classified as VOCs into 15 chemical classes including alkanes, alcohols, carbonyl compounds, methylpyridines, benzothiazoles, N-alkylpyrrolidines, pyrazines, and sesquiterpenoids, some of which were previously reported as repellents, defence compounds or defence pheromones in other organisms, and as sex pheromones in a treefrog. Interestingly, six of the remaining compounds were identified as alkaloids previously reported in other toxic/unpalatable dendrobatid frogs. Conclusions: This is the first report of alkaloids and VOCs found in the Silverstoneia genus, which has been assumed for decades as non-chemically defended. This study establishes HS-SPME/GC-MS as a new application for a simultaneous approach to amphibian alkaloids and VOCs in poison frogs while opens up new research questions to assess the co-occurrence of both type of compounds and to investigate the evolutionary significance of a defence gradient that includes olfactory avoidance, unpalatability, and toxicity in dendrobatids. In addition, our results show that amphibian alkaloids could have a dual function (olfactory at distance, taste by contact) never explored before neither in Silverstonaeia nor in any other dendrobatid species.Fil: Gonzalez, Mabel. Universidad de los Andes; ColombiaFil: Palacios Rodriguez, Pablo. Universidad de los Andes; ColombiaFil: Hernandez Restrepo, Jack. Universidad de los Andes; ColombiaFil: González Santoro, Marco. Universidad de los Andes; ColombiaFil: Amézquita, Adolfo. Universidad de los Andes; ColombiaFil: Brunetti, Andrés Eduardo. Universidade de Sao Paulo; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Carazzone, Chiara. Universidad de los Andes; Colombi

Phylogeny and taxonomy of Circinotrichum, Gyrothrix, Vermiculariopsiella and other setose hyphomycetes

Circinotrichum, Gyrothrix and Vermiculariopsiella represent a complex of dematiaceous, setose, saprobic hyphomycetes that are commonly collected on plant litters in tropical, subtropical to temperate climates. Multi-locus analysis (ITS, LSU, rpb2) and morphological studies revealed that Gyrothrix and Circinotrichum are polyphyletic and species belong to 10 genera grouping in three different clades within Xylariales, named Coniocessiaceae (Circinotrichum and Pirozynskiomyces gen. nov.), Microdochiaceae (Selenodriella and the resurrected genus Peglionia) and the new family Gyrothricaceae (Gyrothrix, Xenoanthostomella, Neogyrothrix gen. nov., Pseudocircinotrichum gen. nov., and Pseudoceratocladium gen. nov.). Vermiculariopsiella (Vermiculariopsiellales, Vermiculariopsiellaceae) is emended for species with setose sporodochia with simple setae (V. dichapetali, V. eucalypticola, V. immersa, V. pini, V. spiralis, V. australiensis sp. nov.) while Vermiculariopsis is resurrected and includes setose fungi with branched setae (Vs. dunni, Vs. eucalypti, Vs. eucalyptigena, Vs. lauracearum, Vs. microsperma, Vs. pediculata and Vs. castanedae sp. nov.).http://www.persoonia.orgam2023BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

New species of Penzigomyces, Sporidesmium and Stanjehughesia from plant debris in Spain

Four new species of Sporidesmium complex collected on plant debris in different protected areas of the Iberian Peninsula are described and illustrated. Penzigomyces basiacutus is characterized by its obclavate to rostrate conidia with a narrowly obconic-truncate basal cell and verruculose apical cell. Sporidesmium corniculatum is distinguished from other species of the genus by its occasional furcate and only transversely septate conidia and Sporidesmium tunicatum by its obclavate to rostrate, verrucose conidia with an apical mucilaginous sheath tunica. Stanjehughesia obclavorostrata is distinguished by its obclavate to rostrate conidia with the basal cell sometimes darker than the rest.The Spanish Ministerio de Ciencia y Tecnología, grant CGL 2011-27185http://www.schweizerbart.de/journals/nova_hedwigiahb2017Microbiology and Plant Patholog

New and interesting chaetothyrialean fungi from Spain

In the course of taxonomic studies on saprobic microfungi from Spain, several slow-growing, dematiaceous hyphomycetes were isolated from soil, submerged plant material and river sediments. Sixteen of these strains were identified as members of the ascomycete order Chaetothyriales on the basis of morphology and DNA sequence analyses of the internal transcribed spacer region and partial large subunit ribosomal RNA gene. These included three novel species (Cladophialophora pseudocarrionii, Cyphellophora chlamydospora, and Rhinocladiella amoena) and five interesting, little-known or clinically-relevant species (Cyphellophora suttonii, Exophiala aquamarina, E. lacus, E. radicis, and Rhinocladiella similis). In addition, Exophiala oligosperma, an emerging opportunistic fungus, was found for the first time in an aquatic freshwater environment (river sediments). Cladophialophora pseudocarrionii resembles C. carrionii in the branching pattern of its conidial chains, but differs from the latter species in its inability to grow at 30 °C. Cyphellophora chlamydospora differs from other species of the genus in the absence of conidiation, producing only chlamydospores in vitro. Rhinocladiella amoena shows branched conidiophores similar to those of R. anceps, R. atrovirens, R. basitona and R. similis, but differs from them in conidial shape and size. The ex-type strain of Phialophora livistonae, included in the phylogenetic study, clustered with high statistical support with members of the genus Cyphellophora and is transferred to this genus.The Spanish Ministry of Economy and Competitivity, grant CGL2011-27185http://link.springer.com/journal/115572017-10-31hb2017Microbiology and Plant Patholog

Genera of phytopathogenic fungi: GOPHY 3

This paper represents the third contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions, information about the pathology, distribution, hosts and disease symptoms for the treated genera, as well as primary and secondary DNA barcodes for the currently accepted species included in these. This third paper in the GOPHY series treats 21 genera of phytopathogenic fungi and their relatives including: Allophoma, Alternaria, Brunneosphaerella, Elsinoe, Exserohilum, Neosetophoma, Neostagonospora, Nothophoma, Parastagonospora, Phaeosphaeriopsis, Pleiocarpon, Pyrenophora, Ramichloridium, Seifertia, Seiridium, Septoriella, Setophoma, Stagonosporopsis, Stemphylium, Tubakia and Zasmidium. This study includes three new genera, 42 new species, 23 new combinations, four new names, and three typifications of older names