7,807 research outputs found

    The genus Gertrudiella broth. (Pottiaceae, Bryophyta) in Paraguay

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    As part of a study of the bryophytes of South America, some samples collected in Paraguay were identified as Gertrudiella uncinicoma, a species of Pottiaceae characterized by the presence of a well-developed central strand and a thick-walled hyalodermis on the stem, lanceolate leaves, laminal cells ventrally mammillose, and several rows of guides cells at the transverse section of the costae. This work represents the first record of the genus from Paraguay. A complete description, ecological comments, illustrations in optical and scanning electron microscopy, and a distribution map are presented.Fil: Jimenez, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Suarez, Guillermo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. Universidad Nacional de Tucumán; Argentin

    Philonotis pomangium (Bartramiaceae, Bryophyta): una adición a la flora briológica de Perú

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    Philonotis pomangium (Bartramiaceae, Bryophyta): una adición a la flora briológica de Perú. Philonotis pomangium es una especie neotropical registrada para Argentina, Bolivia y Brasil. Se caracteriza por las hojas ovado-lanceoladas, células de la lámina cuadradas hacia la base, papilosas en el ángulo distal, y propágulos presentes (tipo "brood branches"). Durante la revisión del género Philonotis en el sur de Sudamérica, algunos especímenes coleccionados en Perú coinciden con P. pomangium, una especie registrada por primera vez para el país. Adicionalmente, se estudió el ejemplar tipo de Philonotis boliviensis, y se la propone aquí como un nuevo sinónimo de P. pomangium. Se presenta una descripción detallada, fotomicrografías en MO y MEB, comentarios sobre la especie y una tabla comparativa de las especies emparentadas de Philonotis del Perú. La distribución Neotropical de P. pomangium se ilustra en un mapa.Philonotis pomangium is a neotropical species recorded from Argentina, Bolivia and Brazil. It is characterized by the ovate-lanceolate leaves, laminal cell quadrate at the base, papillose at the distal angles, and propagules present (brood branches). During the revision of the genus Philonotis in southern South America some samples collected in Peru agreed with P. pomangium, a species not recorded for the country. In addition, the study of the type specimens of Philonotis boliviensis was performed, and it is proposed as a new synonym of P. pomangium. A description, photomicrographs on OM and SEM, comments on the species, and a comparative table for related Philonotis species of Peru are here presented. The Neotropical distribution of P. pomangium is depicted in a map.Fil: Jimenez, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Suarez, Guillermo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

    An Efficient AR Model-Based Method for the Detection of Forced Oscillations in Power Networks: Implementation and Analysis

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    An active research topic is the detection of various oscillations that may lead to instability and potential disruption in the operation of a power network. Forced Oscillations (FOs) play a unique role in power system stability among various oscillations. They are perturbances that change the system’s state and are caused for many reasons, including but not limited to persistent load changes and oscillatory load or generation, fault, triplane, and other mechanical anomalies. These factors can hugely affect the power grid by either increasing or decreasing the amplitude, causing corrupt modes leading to blackouts, affecting the equipment involved, delivering poor power quality, generator tripping, and impeded efforts to monitor modal oscillations. If detected early, FOs can be isolated and mitigated; however, their detection must happen within the first several seconds of the origin of the oscillations. Thus, the development of fast and effective detection algorithms is a key to preventing a power outage. The state of the modern power grid is monitored using a network of Phasor Measurement Units (PMUs). EachPMUkeeps track of complex-valued voltage, current, and frequency as time progresses. These time-series measurements are sensitive enough to detect and localize the cause of oscillations in a power network. In this Project Report, we implement an asymptotic generalized likelihood ratio test statistic (GLRT) to detect FOs in a power network and use an autoregressive process to model the power spectral densities of both the ambient noise and FOs. The estimated power spectral densities, using the magnitude of both current and voltage for a subset of 12 PMU sensors in the network, are substituted in the GLRT statistic to analyze if the known FO is detected. We also focus on the effects of AR model order selection on detection performance. In previous research performed by Pierre, it was hypothesized that the maximum of the detection statistic provided accurate localization of a FO present in the system. Our results demonstrate that the AR model-based GLRT statistic shows excellent reliability in detecting FOs; however, the maximum of the detection statistic is not always observed in the data of the PMU sensor closest to the origin of the FO. Thus, the statement that the location of a FO can be identified based on the location of the maximum of the detection statistic must be investigated further, leaving us with a bulk of future work

    An Exploration of The Application of Spatial Network Screening Methods On Iowa Rural Road Crashes

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    Safety on the roadway system is important due to its usage on mobility and accessibility, especially on rural roads in the state of Iowa. Single vehicle run off road crashes have been increasing in the United States and studies and research has increased due to the concern with those. For this effort, a spatial-temporal method of traffic safety network screening is utilized in order to evaluate the concerning type of crashes in particular locations. The study of single vehicle run off road crashes using the proposed method is important since distributions and clusters of crashes along roadways can be observed and further evaluations can be performed

    The Good, the Bad and the Ugly of Corporate Social Responsibility: Taking a Look at the Case of Empresas Públicas de Medellín

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    The following research takes a look at the concept of Corporate Social Responsibility (CSR) focusing on the good and bad aspects it presents. The analysis is supported by three theories: (1) CSR and the Competitive Advantage by Kramer and Porter (2002), where CSR is seen as tool to achieve competitive advantage not only benefiting the company but the society around it, (2) Stages of CSR by Zadek (2006), presenting CSR as learning process for the organizations and the society, and (3) Development of Community/Company Relationships with CSR by Marin, Rubio and Ruiz (2009), considering CSR as a key for a good perception of consumers and the relationship established among the company and its consumers. Finally there is a study of a Colombian company really active in the implementation of CSR. Taking this approach will allow for greater understanding on the importance of CSR in addition to its wider significance in society and with a direct link to Medellin, Colombia

    Transcriptomic and Epigenetic Responses to Environmental Stress in Marine Bivalves with a Focus on Harmful Algal Blooms

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    Global change poses new threats for life in the oceans forcing marine organisms to respond through molecular acclimatory and adaptive strategies. Although bivalve molluscs are particularly tolerant and resilient to environmental stress, they must now face the challenge of more frequent and severe Harmful Algal Blooms (HABs) episodes. These massive outbreaks of microalgae produce toxins that accumulate in the tissues of these filter-feeder organisms, causing changes in their gene expression profiles, which in turn modify their phenotype in order to maintain homeostasis. Such modifications in gene expression are modulated by epigenetic mechanisms elicited by specific environmental stimuli, laying the foundations for long-term adaptations. The present work aims to examine the links between environmental stress in bivalve molluscs (with especial emphasis on Harmful Algal Blooms) and specific epigenetic marks triggering responses through modifications in gene expression patterns. Overall, a better understanding of the molecular strategies underlying the conspicuous stress tolerance observed in bivalve molluscs will provide a framework for developing a new generation of biomonitoring strategies. In addition, this strategy will represent a valuable contribution to our knowledge in acclimatization, adaptation and survival. With that goal in mind, the present work has generated transcriptomic data using RNA-Seq and microarray technologies, facilitating the characterization and investigation of the epigenetic mechanisms used by the Mediterranean mussel Mytilus galloprovincialis during responses to HAB exposure. That information was made publicly available through a specialized online resource (the Chromevaloa Database, chromevaloa.com) assessing the response of chromatin-associated transcripts to Okadaic Acid. Specific epigenetic marks have been assessed under lab-controlled exposure experiments simulating the natural development of the HAB Florida Red Tide (FRT). Results demonstrate a role for the phosphorylation of histone H2A.X and DNA methylation in the response to FRT in the Eastern oyster Crassostrea virginica. Lastly, the study of co-expression networks based on RNA-Seq data series from the Pacific oyster Crassostrea gigas reveals dynamic transcriptomic patterns that vary with time, stressor and tissue. However, consistent functional profiles support the existence of a core response to general conditions of environmental stress. Such response involves metabolic and transport processes, response to oxidative stress and protein repair or disposal, as well as the activation of immune mechanisms supporting a tightly intertwined neuroendocrine-immune regulatory system in bivalves

    [CHAIN UP GROUP] Applied Technology Group Project

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    This document presents the draft of the introductory chapter as well as the research and planning aspects of developing a text hosting service application based on block chain technology named‘Chain UP. This report represents part I of the continuous assessment of the year-module named Applied Technology Group Project for the 3rd year of the Information Technology course at CCT College Dublin. This chapter contains an introduction to Blockchain’s concepts and an overview of its benefits and the latest industry applications of this technology, specifically the financial services industry and the data security industry. In the next chapters, we will discuss how those concepts influenced our definition of the scope of the project and go into further detail on the proof of concept in Blockchain through developing a text hosting application. A description of the provisional architecture diagram is also included. The schedule of tasks for the project can be found in the section named ‘Schedule’ in appendix B. Each team member contributed a report assessing their work and impact of duties on the deliverables up to this point. These can be found under the section named Appendix A – Individual Contribution Report

    Plantas y hongos tintóreos de los wichís del Gran Chaco

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    Se presentan los resultados de una investigación etnobotánica que trata los tintes vegetales y fúngicos entre los indígenas wichí del Chaco Semiárido. Se realizaron trabajos de campo con informantes calificados y ocasionales de ambos sexos en localidades de las provincias argentinas de Salta y Formosa. Asimismo, se hizo una revisión minuciosa de la bibliografía vinculada con el tema. Se encontraron 24 especies de plantas y 2 de hongos que son usadas para colorear productos textiles realizados a partir de fibras de cháguar (Bromelia hieronymi y B. urbaniana). Se proporcionan informaciones y detalles sobre los nombres vernáculos de las especies, las partes usadas, los procedimientos de tinción y los colores logrados. El número total de plantas tintóreas encontrado es alto comparado con los que fueron citados para otras etnias chaquenses y se registraron especies que antes no fueron mencionadas como tintóreas entre los wichís.Dye plants and fungi among the Wichí people of the Gran Chaco. This paper presents the results of an ethnobotanical investigation into plant and fungal dyes used by the Wichí people of the Semiarid Chaco. Fieldwork was carried out with occasional and key informants, both men and women, in several locations of Salta and Formosa provinces in Argentina. Moreover, a detailed examination of the bibliography on the topic was conducted. Twenty-four plant species and two fungi that are used for coloring textile products made from cháguar fibers (Bromelia hieronymi and B. urbaniana) were found. Information and details on the vernacular names of the species, the parts that are used, the dying technique and the colors obtained are provided. The total number of dye plants found is high compared with the ones cited among other Chaco ethnic groups, and records were made of species that had not previously been mentioned among the Wichí people as being used for dyes.Fil: Suarez, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Arenas Rodriguez, Pastor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentin
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