27 research outputs found

    Suitable conditions for natural regeneration in variable retention harvesting of southern Patagonian Nothofagus pumilio forests

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    Background: Variable retention (aggregated and dispersed retention) harvesting proposed for Nothofagus pumilio was designed for timber purposes and biodiversity conservation. Harvesting by opening canopy generates different microenvironments and creates contrasting conditions for seedling establishment, growth, and eco-physiology performance due to synergies (positives or negatives) with biotic and abiotic factors. This study evaluated the regeneration in different microenvironment conditions within managed stands during 5 years after harvesting. Remnant forest structure after harvesting and different microenvironments were characterized in managed stands, where 105 regeneration plots were measured (3 stands × 7 microenvironments × 5 replicas). We characterized the seedling bank, as well as growth and ecophysiology performance of the regeneration. Univariate and multivariate analyses were conducted for the comparisons. Results: Microenvironments offered different environmental conditions for natural regeneration (soil moisture and light availability). Seedling under debris and dicot plants showed better eco-physiological performance, establishment, and growth than plants growing under monocots or located in the dispersed retention without the protection of other understory plants. The most unfavorable microenvironment conditions were high canopy cover of remnant trees (inside the aggregates or close to trees in the dispersed retention) and heavily impacted areas (skidder extraction roads). Conclusions: Favorable microenvironments in the harvested areas will improve the natural recruitment, growth, and eco-physiology performance of the natural regeneration after harvesting. It is necessary to develop new silvicultural practices that decrease the unfavorable microenvironments (e.g., road density or excessive woody accumulation), to assure the success of the proposed silvicultural method.EEA Santa CruzFil: Toro Manríquez, Mónica D.R. Centro Austral de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Cellini, Juan Manuel. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Investigaciones en Maderas; ArgentinaFil: Lencinas, María Vanessa. Centro Austral de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Universidad Nacional de la Patagonia Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Peña Rojas, Karen A. Universidad de Chile. Facultad de Ciencias Forestales y de Conservación de la Naturaleza. Departamento de Silvicultura y Conservación de la Naturaleza; ChileFil: Martínez Pastur, Guillermo José. Centro Austral de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

    Knowledge arising from long-term research of variable retention harvesting in Tierra del Fuego: where do we go from here?

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    Nothofagus pumilio forests in Tierra del Fuego are the southernmost forests in the world, where extreme climate conditions represent a challenge to attain sustainable forest management. Retention forestry was proposed as an alternative to increase the species conservation in managed stands. Here, we synthetized results related to the implementation of a variable retention harvesting based on a combination of aggregate patches and dispersed retention during the last 18 years comparing with other silviculture proposals (e.g., shelterwood cuts) and control treatments (primary unmanaged forests). We summarized the results for (i) sawmill operations, (ii) timber yield, (iii) overstory stability, (iv) forest structure, (v) microclimate and natural cycles, (vi) natural regeneration dynamics (flowering, seeding, foraging, recruitment, growth, and mortality), and (vii) biodiversity (mammals, understory plants, mistletoes, birds, arthropods, mosses, lichens, and fungi). In general, aggregate patches maintained forest structure and micro-environmental variables, and slightly increased biodiversity and forest reproduction variables compared to unmanaged primary forests. On the contrary, dispersed retention decreased forest structure variables and greatly increased biodiversity (richness and abundance) when it was compared to unmanaged primary forests. Ecological conditions are influenced by variable retention harvesting, but direction and magnitude of the effect depend and differ according to retention types. Besides this, biodiversity taxa greatly differed among groups depending on retention types. In general, the species assemblages in aggregate patches were similar to those found in primary unmanaged forests, while they were significantly modified in the dispersed retention. This occurred due to (i) local extinction of some original species, (ii) the introduction of native species from the surrounding environments, or (iii) the invasion of exotic species. This silvicultural method has been a useful tool to conserve biodiversity and ecosystem functions, approaching to the balance between economy, ecology, and social requirements in the managed areas.EEA Santa CruzFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Rosas, Yamina Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Toro Manríquez, Mónica D.R. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Huertas Herrera, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Miller, Juan A. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Cellini, Juan Manuel. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Investigaciones en Maderas; ArgentinaFil: Barrera, Marcelo Daniel. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Investigaciones en Maderas; ArgentinaFil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Universidad Nacional de la Patagonia Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; Argentin

    SERVERUS: LA IMPLEMENTACIÓN DEL BLOCKCHAIN EN LA VIDA COTIDIANA (SERVERUS: THE IMPLEMENTATION OF BLOCKCHAIN IN EVERYDAY LIFE)

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    Mucho se ha hablado en los últimos años sobre la industria 4.0, sin embargo, fue hasta hace poco que se implementó realmente tanto en la industria, como en la vida cotidiana. Este término se le ha acuñado al uso de tecnologías como sistemas ciberfísicos (Samaniego & Deters, 2016), a la cultura maker (cultura Hágalo usted mismo), a la manufactura automatizada, al servicio al cliente con el uso de Inteligencia artificial (bots), al internet de las cosas y al blockchain, donde este último, ha demostrado un gran potencial con innumerables aplicaciones que todavía se siguen desarrollando. Su principal uso ha sido en el intercambio de criptodivisas tales como el Bitcoin, Ethereum, entre otras cerca de 1900 criptomonedas que diariamente mueven en el mercado cerca de 12 mil MDD. Por otro lado, el intercambio de dinero no es la única aplicación que tiene el blockchain, por mencionar algunas, se tienen: registro de propiedades, almacenamiento en la nube, redes privadas de intercambio de información, identidad digital para mejor control de información, gestión de autorías, y en general, cualquier contrato que pueda hacerse físicamente. Serverus es un servicio de transmisión de datos y encriptamiento con implementación de tecnología blockchain, que puede ser aplicado en el uso personal, la administración de recursos en MiPymes, además de poder programarse en redes más robustas de seguridad informática gubernamental. Este servicio se destaca por buscar el impulso de la tecnología de punta en México, generando una cultura diferente ante el inminente cambio en la gestión de data digitales en la industria, la oficina y la vida doméstica.Palabras Clave: blockchain 3.0, Ethereum, industria 4.0, privacidad. AbstractIn recent years it has been talked a lot about 4.0 industry, however, it was until recently that it was really implemented as in industry as in everyday life. This term has been coined to the use of technologies such as cyberphysical systems (Samaniego & Deters, 2016), maker culture (Do-it-yourself culture), automated manufacturing, customer service with the use of artificial intelligence (Bots), IoT and blockchain. The latter which has shown great potential with innumerable applications that are still being developed. It’s main use has been in the exchange of cryptocurrency such as the famous Bitcoin, Ethereum, among around other 1900 cryptocurrencies that daily move in the market about 12 thousand MDD. On the other hand, money exchange is not the only application that Blockchain has; to name a few, there are: property registry, cloud storage, information interchange private networks, digital identity for better control of information, authorship management and, in general, any contract that can be done physically. Serverus is a data encryption and transmission service with the implementation of blockchain technology, which can be applied to personal use, resource management in MiPymes, besides allowing it’s programming in robuster networks. This service stands out for seeking the momentum of cutting-edge technology in Mexico, generating a different culture before the imminent change of digital data management in the industry, office and domestic life.Keywords: blockchain 3.0, Ethereum, Industry 4.0, privacy

    New Polyether Triterpenoids from Laurencia viridis and Their Biological Evaluation

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    The red seaweed Laurencia viridis is a rich source of secondary metabolites derived from squalene. New polyethers, such as iubol (2), 22-hydroxy-15(28)- dehydrovenustatriol (3), 1,2-dehydropseudodehydrothyrsiferol (4), and secodehydrothyrsiferol (5) have been isolated and characterized from this alga. The structures were determined through the interpretation of NMR spectroscopic data and the relative configuration was proposed on the basis of NOESY spectrum and biogenetic considerations. All new compounds exhibited significant cytotoxic activity against a panel of cancer cell lines

    Conservation values of understory vascular plants in even- and uneven-aged <i>Nothofagus antarctica</i> forests

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    Usually, stands with aging trees are considered forests with higher conservation values, regardless their structural diversity and other functional attributes. Natural stands present a wide range of age structures, from even-aged stands growing at different development growth phases (e.g. CO = stands at initial or final optimum development growth phase, MD = stands at mature or decaying development growth phases) to uneven-aged stands with mixed development growth phases (e.g. UOG = stands combining mature or decaying development growth phases with initial or final optimum development growth phases, UMD = stands combining only mature and decaying development growth phases). The aim of this work was to compare richness and cover of understory vascular plants of even- and uneven-aged stands of Nothofagus antarctica (nire) forests in Tierra del Fuego (Argentina), and relate these characteristics with abiotic, soil and forest structure variables. A total of 75 stands were sampled across the natural range distribution of the forests, where understory (point intercept method), forest structure (angle count sampling and eye-fish photos) and environmental (soil) variables were measured. 17 one-way ANOVAs were conducted using Tukey test at p   UOG > MD > CO (17–28 total, and 13–24 native species, respectively). Neither exotic species richness (4–5 species) nor understory cover significantly changed among treatments (total, dicots, ferns and bryophytes). However, monocots cover significantly differed among treatments (F = 3.9, p = 0.012), where UMD > MD > UOG > CO. Finally, indicator species cover for environmental degradation did not present significant differences (F = 2.1, p = 0.106), but they were positive related to forests growing in mature stages. We concluded that uneven-aged stands presented significantly higher conservation values compared to even-aged stands, where mature/decay stands have better conservation values than optimum growth development phases. These findings can be used for better silviculture practices that combine silvopastoral use and conservation strategies.Facultad de Ciencias Agrarias y ForestalesConsejo Nacional de Investigaciones Científicas y Técnica

    Synergies and Trade-Offs of National Conservation Policy and Agro-Forestry Management Over Forest Loss in Argentina During the Last Decade

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    One reason for the decline of natural forest is that many ecosystem services (ESs) are usually not priced and values were only considered provisioning services. Argentina enacted the National Law 26,331/07, which regulates protection, enrichment, restoration and management of native forests and its environmental services. The objective is to determine the ecological and sociopolitical factors that influence the dynamics of forest cover loss before and after the lawimplementation and discuss the effectiveness of conservation and forest management policies. Satellite images, national ordination, forest regions maps and other variables were combined in GIS with national databases (social, agriculture, industry) to determine the evolution of potential drivers of forest changes. The main potential drivers were: (i) population growth, (ii) road density, (iii) crops area, (iv) livestock and (v) fires. Payment of incentives by government cannot fully stop the deforestation but decrease the forest loss rate. New approaches must be considered to built-in flexibility actions according to local conditions and constraints, which are influenced by social and economic contexts. Thus, it is necessary to establish new regional policies associated with the factors linked to the loss of forest cover, in the search for sustainable management alternatives that combine economic and conservation proposals.Laboratorio de Investigaciones en MaderaConsejo Nacional de Investigaciones Científicas y TécnicasInstituto Nacional de Tecnología Agropecuari

    Sistema de evaluación institucional en enseñanza obligatoria en Iberoamérica

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    La presente aportación se focaliza, en este contexto, en la evaluación institucional externa (vinculada o no a la autoevaluación interna) y, por tanto, considera prioritariamente la manera como se evalúan los centros educativos como totalidad y no tanto alguno de sus aspectos (evaluación de la dirección, de los profesores, de los programas, etc.), que también pueden estar considerados. El énfasis también está en conocer la organización y desarrollo del sistema de evaluación. Recoge la visión de 43 especialistas de trece países iberoamericanos sobre las formas de entender y promover la evaluación institucional en sus centros educativos. Sus aportaciones, que deben contextualizarse en las particularidades educativas de sus países (ya presentadas en anteriores informes de la RedAGE), presentan los aspectos generales y normativos de la evaluación, las formas cómo se organiza, los efectos institucionales que tienen y algunas reflexiones, retos y propuestas para la mejora. Su orientación es claramente práctica y se vincula al encuentro anual que la RedAGE realizado los días 16 y 17 de mayo de 2016 en la ciudad de Leiria (Portugal). Allí, los representantes de las organizaciones miembro seleccionaron la temática por su interés actual (con clara vinculación a la mejora de los sistemas educativos y la acreditación institucional), consensuaron la estructura de las aportaciones y realizaron un intercambio de posibles ideas sobre la temática. Se cubre así y como en ocasiones anteriores el propósito fundamental de la RedAGE, como es el de fomentar el intercambio de experiencias, la promoción del conocimiento sobre administración y gestión educativa y la reflexión sobre la práctica de la gestión. La finalidad última sigue siendo la de mejorar el funcionamiento de los centros educativos (y, a través de ellos, de los sistemas educativos), procurando sean de calidad y un instrumento para el cambio profesional y social

    Adherencia a la TARV en VIH: la importancia del contexto socio-cultural implicado

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    Entrega de malas noticias en la práctica clínica

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