604 resultados para Caspian tern.


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The interface between climate and ecosystem structure and function is incompletely understood, partly because few ecological records start before the recent warming phase. Here, we analyse an exceptional 100-yr long record of the great tit (Parus major) population in Switzerland in relation to climate and habitat phenology. Using structural equation analysis, we demonstrate an uninterrupted cascade of significant influences of the large-scale atmospheric circulation (North-Atlantic Oscillation, NAO, and North-sea – Caspian Pattern, NCP) on habitat and breeding phenology, and further on fitness-relevant life history traits within great tit populations. We then apply the relationships of this analysis to reconstruct the circulation-driven component of fluctuations in great tit breeding phenology and productivity on the basis of new seasonal NAO and NCP indices back to 1500 AD. According to the structural equation model, the multi-decadal oscillation of the atmospheric circulation likely led to substantial variation in habitat phenology, productivity and consequently, tit population fluctuations with minima during the "Maunder Minimum" (∼ 1650–1720) and the Little Ice Age Type Event I (1810–1850). The warming since 1975 was not only related with a quick shift towards earlier breeding, but also with the highest productivity since 1500, and thus, the impact of the NAO and NCP has contributed to an unprecedented increase of the population. A verification of the structural equation model against two independent data series (1970–2000 and 1750–1900) corroborates that the retrospective model reliably depicts the major long-term NAO/NCP impact on ecosystem parameters. The results suggest a complex cascade of climate effects beginning at a global scale and ending at the level of individual life histories. This sheds light on how large-scale climate conditions substantially affect major life history parameters within a population, and thus influence key ecosystem parameters at the scale of centuries.

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Entscheidungsfragen lassen sich bei anspruchsvollen Managementaufgaben nicht immer scharf mit ja oder nein beantworten. Vielmehr geht es um ein Abwägen unterschiedlicher Einflussfaktoren und die Antwort für eine Problemlösung lautet oft ‚ja unter Vorbehalt' oder ‚sowohl als auch´. Die Antwort ist unscharf und kann Werte zwischen 0 und 1 annehmen. Die unscharfe Logik entspricht der menschlichen Wahrnehmung. Sie vermag neben quantitativen Grössen qualitative Einschätzungen mit einzubeziehen. Um Entscheidungsfindung bei vagem Sachverhalt in Informationssystemen zu ermöglichen, müssen Managementmethoden mit unscharfen Konzepten erweitert werden. Der Beitrag führt in die unscharfe Logik ein und zeigt deren Potenzial anhand der unscharfen Scoringmethode fRFM (fuzzy Recency-, Frequency- und Monetary-Werte) auf, die beim schweizerischen Detailhändler coop@home testweise angewendet wurde.

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Stable water isotope (delta(18)O, deltaD) data from a high elevation (5100 masl) ice core recovered from the Tien Shan Mountains, Kyrgyzstan, display a seasonal cycle in deuterium excess (d = deltaD - 8* delta(18)O) related to changes in the regional hydrologic cycle during 1994 - 2000. While there is a strong correlation (r(2) = 0.98) between delta(18)O and dD in the ice core samples, the regression slope (6.9) and mean d value (23.0) are significantly different than the global meteoric water line values. The resulting time-series ice core d profile contains distinct winter maxima and summer minima, with a yearly d amplitude of similar to 15 - 20parts per thousand. Local-scale processes that may affect d values preserved in the ice core are not consistent with the observed seasonal variability. Data from Central Asian monitoring sites in the Global Network of Isotopes in Precipitation (GNIP) have similar seasonal d changes. We suggest that regional-scale hydrological conditions, including seasonal changes in moisture source, transport, and recycling in the Caspian/ Aral Sea region, are responsible for the observed spatial and temporal d variability.

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In the summers of 2001 and 2002, glacio-climatological research was performed at 4110-4120 m a.s.l. on the Belukha snow/firn plateau, Siberian Altai. Hundreds of samples from snow pits and a 21 m snow/firn core were collected to establish the annual/seasonal/monthly depth-accumulation scale, based on stable-isotope records, stratigraphic analyses and meteorological and synoptic data. The fluctuations of water stable-isotope records show well-preserved seasonal variations. The delta(18)O and delta D relationships in precipitation, snow pits and the snow/firn core have the same slope to the covariance as that of the global meteoric water line. The origins of precipitation nourishing the Belukha plateau were determined based on clustering analysis of delta(18)O and d-excess records and examination of synoptic atmospheric patterns. Calibration and validation of the developed clusters occurred at event and monthly timescales with about 15% uncertainty. Two distinct moisture sources were shown: oceanic sources with d-excess < 12 parts per thousand, and the Aral-Caspian closed drainage basin sources with d-excess > 12 parts per thousand. Two-thirds of the annual accumulation was from oceanic precipitation, of which more than half had isotopic ratios corresponding to moisture evaporated over the Atlantic Ocean. Precipitation from the Arctic/Pacific Ocean had the lowest deuterium excess, contributing one-tenth to annual accumulation.

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A complete succession of the lacustrine sediment sequence deposited during the last ∼600,000 years in Lake Van, Eastern Anatolia (Turkey) was drilled in 2010 supported by the International Continental Scientific Drilling Program (ICDP). Based on a detailed seismic site survey, two sites at a water depth of up to 360 m were drilled in summer 2010, and cores were retrieved from sub-lake-floor depths of 140 m (Northern Basin) and 220 m (Ahlat Ridge). To obtain a complete sedimentary section, the two sites were multiple cored in order to investigate the paleoclimate history of a sensitive semi-arid region between the Black, Caspian, and Mediterranean seas. This introductory paper provides background information of the deep drilling project and an overview of the studies presented in this special volume by the PALEOVAN science team dealing with chronology, paleomagnetism, paleoenvironmental proxies, geophysical and petrophysical investigations as well as pore-water and fluid transport.

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OBJECTIVE How long clinicians should wait before considering an antipsychotic ineffective and changing treatment in schizophrenia is an unresolved clinical question. Guidelines differ substantially in this regard. The authors conducted a diagnostic test meta-analysis using mostly individual patient data to assess whether lack of improvement at week 2 predicts later nonresponse. METHOD The search included EMBASE, MEDLINE, BIOSIS, PsycINFO, Cochrane Library, CINAHL, and reference lists of relevant articles, supplemented by requests to authors of all relevant studies. The main outcome was prediction of nonresponse, defined as <50% reduction in total score on either the Positive and Negative Syndrome Scale (PANSS) or Brief Psychiatric Rating Scale (BPRS) (corresponding to at least much improved) from baseline to endpoint (4-12 weeks), by <20% PANSS or BPRS improvement (corresponding to less than minimally improved) at week 2. Secondary outcomes were absent cross-sectional symptomatic remission and <20% PANSS or BPRS reduction at endpoint. Potential moderator variables were examined by meta-regression. RESULTS In 34 studies (N=9,460) a <20% PANSS or BPRS reduction at week 2 predicted nonresponse at endpoint with a specificity of 86% and a positive predictive value (PPV) of 90%. Using data for observed cases (specificity=86%, PPV=85%) or lack of remission (specificity=77%, PPV=88%) yielded similar results. Conversely, using the definition of <20% reduction at endpoint yielded worse results (specificity=70%, PPV=55%). The test specificity was significantly moderated by a trial duration of <6 weeks, higher baseline illness severity, and shorter illness duration. CONCLUSIONS Patients not even minimally improved by week 2 of antipsychotic treatment are unlikely to respond later and may benefit from a treatment change.

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The sweet chestnut (Castanea sativa Mill.) is the only native species of the genus in Europe. The broad diffusion and active management by man resulted in the establishment of the species at the limits of its potential ecological range, which makes it difficult to trace its original natural area. The present distribution ranges from North-Western Africa (e.g. Morocco) to North-Western Europe (southern England, Belgium) and from south-western Asia (e.g. Turkey) to Eastern Europe (e.g. Romania), the Caucasus (Georgia, Armenia) and the Caspian Sea. In Europe the main chestnut forests are concentrated in a few countries such as Italy, France and the Iberian Peninsula. The sweet chestnut has a remarkable multipurpose character, and may be managed for timber production (coppice and high forest) as well as for fruit production (traditional orchards), including a broad range of secondary products and ecosystem services.

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The dataset is based on samples collected in the summer of 2001 in the Western Black Sea in front of Bulgaria coast (transects at c. Kaliakra and c. Galata). The whole dataset is composed of 26 samples (from 10 stations of National Monitoring Grid) with data of mesozooplankton species composition abundance and biomass. Samples were collected in discrete layers 0-10, 10-20, 10-25, 25-50, 50-75, 75-90. Zooplankton samples were collected with vertical closing Juday net,diameter - 36cm, mesh size 150 µm. Tows were performed from surface down to bottom meters depths in discrete layers. Samples were preserved by a 4% formaldehyde sea water buffered solution. Sampling volume was estimated by multiplying the mouth area with the wire length. Mesozooplankton abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Lyudmila Kamburska and Kremena Stefanova using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972). Taxon-specific abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Copepods and Cladoceras were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Lyudmila Kamburska and Kremena Stefanova using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972).

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Fil: Terán, Sisto.

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Se analizó la equivalencia entre tres sistemas de organización del conocimiento (SOC), identificándose 235 epígrafes de la Lista de Encabezamientos de Materia para Bibliotecas (LEMB) y 174 descriptores del Tesauro de la Unesco (TU) referidos a Bibliotecología. Se tradujeron todos ellos a notaciones de la Clasificación Decimal Universal (CDU), obteniéndose 286 notaciones simples y precoordinadas. Los resultados fueron: Entre LEMB y CDU: sin equivalencia: 27 epígrafes (11,4); equivalencia parcial (epígrafe más específico que notación): 9 (3,9) y equivalencia exacta: 199 (84,6). La equivalencia exacta fue sin precoordinación: 117 (49,6), precoordinación entre clases principales: 60 (25,4) y precoordinación con auxiliares: 22 (9,6). Entre TU y CDU los resultados fueron: sin equivalencia: 33 descriptores (19,0); equivalencia parcial (descriptor más específico que notación): 25 (14,3): equivalencia exacta: 116 (66,7). La equivalencia exacta también fue de tres tipos: sin precoordinación: 74 (42,5), precoordinación entre clases principales 31 (17,9), precoordinación con auxiliares: 11 (6,3). Se establecieron 205 equivalencias de los tres SOC (71,7), hecho que sugiere que CDU puede actuar como SOC intermediario entre los otros dos.

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La interoperabilidad entre distintos sistemas de organización del conocimiento (SOC) ha cobrado gran importancia en los últimos tiempos, con el propósito de facilitar la búsqueda simultánea en varias bases de datos o fusionar distintas bases de datos en una sola. Las nuevas normas para el diseño y desarrollo de SOC, la estadounidense Z39.19:2005 y la británica BS 8723-4:2007, incluyen recomendaciones detalladas para la interoperabilidad. También se encuentra en preparación una nueva norma ISO 25964-1 sobre tesauros e interoperabilidad que se agregará a las anteriores. La tecnología disponible proporciona herramientas para este fin, como son los formatos y requisitos funcionales de autoridades y las herramientas de la Web Semántica RDF/OWL, SKOS Core y XML. Actualmente es difícil diseñar y desarrollar nuevos SOC debido a los problemas económicos, de modo que la interoperabilidad hace posible aprovechar los SOC existentes. En este trabajo se revisan los conceptos, modelos y métodos recomendados por las normas, así como numerosas experiencias de interoperabilidad entre SOC que han sido documentadas.

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Enmarcada por los estudios de historia intelectual y de las ideas escritos en los últimos años sobre intelectuales y cultura en la década del 60 en la Argentina (Terán 1991); (Sigal 1991), (Rivera 1998) y América Latina (Gilman 2003), nuestra ponencia se propone rescatar la obra del escritor argentino Germán Rozenmacher (1936-1971) para pensar una representación diferente (apartada de las ya canonizadas en las obras de Rodolfo Walsh, Julio Cortázar y, recientemente, Osvaldo Lamborghini) de la revolución en la literatura. Realizaremos un recorrido crítico por dos de los cuentos de Los ojos del tigre (1968) que ponen en primer plano la violencia política y los ideales revolucionarios, "Cochecito" y "Los ojos del tigre", para relevar recursos, motivos y planteos ético-morales. Los temas a tratar en este recorrido son, entre otros: la puesta en escena de la tensión entre los ideales revolucionarios y las relaciones amorosas; la construcción de personajes con un perfil psicólogico denso; el coloquialismo, el monólogo interior y la polifonía como recursos narrativos principales; etc. El análisis intentará detectar cómo Rozenmacher problematizó los movimientos revolucionarios que comenzaban a surgir en los sesenta en la Argentina

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Hasta el año 2010, no disponíamos de información sobre las bibliotecas argentinas que hacían uso de la web social y qué herramientas y servicios estaban empleando. En el año 2011 se realizó un relevamiento para indagar ese aspecto, pero focalizando la investigación en las bibliotecas universitarias argentinas. En esta oportunidad, buscamos ampliar el espectro de investigación, incorporando en un nuevo relevamiento otros tipos de unidades de información y conocer otros aspectos referidos al uso, los contenidos y la prestación de servicios. Desde LABIAR 2.0 y a partir de este trabajo buscamos generar un espacio de encuentro, de debate y reflexión sobre los usos que las bibliotecas argentinas hacen de la web social, tanto en sus prácticas a nivel interno como servicios a sus usuarios.