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Sample records for ice lobe tierra

  1. Hummocky moraine: sedimentary record of stagnant Laurentide Ice Sheet lobes resting on soft beds

    Science.gov (United States)

    Eyles, N.; Boyce, J. I.; Barendregt, R. W.

    1999-02-01

    Over large areas of the western interior plains of North America, hummocky moraine (HM) formed at the margins of Laurentide Ice Sheet (LIS) lobes that flowed upslope against topographic highs. Current depositional models argue that HM was deposited supraglacially from stagnant debris-rich ice (`disintegration moraine'). Across southern Alberta, Canada, map and outcrop data show that HM is composed of fine-grained till as much as 25 m thick containing rafts of soft, glaciotectonized bedrock and sediment. Chaotic, non-oriented HM commonly passes downslope into weakly-oriented hummocks (`washboard moraine') that are transitional to drumlins in topographic lows; the same subsurface stratigraphy and till facies is present throughout. These landforms, and others such as doughnut-like `rim ridges', flat-topped `moraine plateaux' and linear disintegration ridges, are identified as belonging to subglacially-deposited soft-bed terrain. This terrain is the record of ice lobes moving over deformation till derived from weakly-lithified, bentonite-rich shale. Drumlins record continued active ice flow in topographic lows during deglaciation whereas HM was produced below the outer stagnant margins of ice lobes by gravitational loading (`pressing') of remnant dead ice blocks into wet, plastic till. Intervening zones of washboard moraine mark the former boundary of active and stagnant ice and show `hybrid' drumlins whose streamlined form has been altered by subglacial pressing (` humdrums') below dead ice. The presence of hummocky moraine over a very large area of interior North America provides additional support for glaciological models of a soft-bedded Laurentide Ice Sheet.

  2. Behaviour of the lake district ice lobe of the Scandinavian ice sheet during the younger dryas chronozone (ca. 12 800 - 11 500 years ago)

    Energy Technology Data Exchange (ETDEWEB)

    Lunkka, J.P.; Erikkilae, A. [Oulu Univ. (Finland)

    2012-04-15

    It is highly relevant to picture the conditions that prevailed under and in front of the ice sheets as they were stationary or in equilibrium for many hundreds of years. This knowledge is particularly relevant when planning to dispose of spent nuclear fuel in a repository underground. For estimating what kind of conditions might exist at the ice margin basic knowledge is needed from the palaeoice sheets that remained stationary for long periods of time. During Younder Dryas Stadial (c. 12 800 - 11 500 years ago) glaciers remained stationary or advanced worldwide as a result of climate cooling. The major end moraine complexes that run around Fennoscandia, Russian Karelia and the Kola Peninsula were deposited at that time and mark the former Younger Dryas ice margin. It this work the palaeoenvironments have been reconstructed in order to reveal the conditions that existed for more than 1000 years in the area where the former Lake District Ice Lobe of the Scandinavian Ice Sheet was in the Salpausselkae zone in southern Finland. Work was carried out using GIS-based reconstruction tools, sedimentological and geophysical (ground penetrating radar) methods. In addition, a detailed palaeoenvironmental reconstruction was produced for the Kylaeniemi area which forms a part of the Salpausselkae II end moraine. The GIS-based reconstructions clearly indicate that the ice grounding line of the Lake District Ice Lobe was standing in shallow water depth in the Baltic Ice Lake. The water depth in front of Salpausselkae I, which marks the ice margin at c. 12 500 years ago was mainly between 20-40 metres. When the ice margin was in Salpausselkae II at around 11 700 years ago the water depth in front of the ice margin was on average less than 20 metres. Although the surface profile of ice was not possible to calculate subgalcial and ice frontal landforms indicate that subgalcial tunnel systems were responsible for releasing melt water and sediment to the ice margin throughout the

  3. Behaviour of the lake district ice lobe of the Scandinavian ice sheet during the younger dryas chronozone (ca. 12 800 - 11 500 years ago)

    International Nuclear Information System (INIS)

    Lunkka, J.P.; Erikkilae, A.

    2012-04-01

    It is highly relevant to picture the conditions that prevailed under and in front of the ice sheets as they were stationary or in equilibrium for many hundreds of years. This knowledge is particularly relevant when planning to dispose of spent nuclear fuel in a repository underground. For estimating what kind of conditions might exist at the ice margin basic knowledge is needed from the palaeoice sheets that remained stationary for long periods of time. During Younder Dryas Stadial (c. 12 800 - 11 500 years ago) glaciers remained stationary or advanced worldwide as a result of climate cooling. The major end moraine complexes that run around Fennoscandia, Russian Karelia and the Kola Peninsula were deposited at that time and mark the former Younger Dryas ice margin. It this work the palaeoenvironments have been reconstructed in order to reveal the conditions that existed for more than 1000 years in the area where the former Lake District Ice Lobe of the Scandinavian Ice Sheet was in the Salpausselkae zone in southern Finland. Work was carried out using GIS-based reconstruction tools, sedimentological and geophysical (ground penetrating radar) methods. In addition, a detailed palaeoenvironmental reconstruction was produced for the Kylaeniemi area which forms a part of the Salpausselkae II end moraine. The GIS-based reconstructions clearly indicate that the ice grounding line of the Lake District Ice Lobe was standing in shallow water depth in the Baltic Ice Lake. The water depth in front of Salpausselkae I, which marks the ice margin at c. 12 500 years ago was mainly between 20-40 metres. When the ice margin was in Salpausselkae II at around 11 700 years ago the water depth in front of the ice margin was on average less than 20 metres. Although the surface profile of ice was not possible to calculate subgalcial and ice frontal landforms indicate that subgalcial tunnel systems were responsible for releasing melt water and sediment to the ice margin throughout the

  4. Mass balance and sliding velocity of the Puget lobe of the cordilleran ice sheet during the last glaciation

    Science.gov (United States)

    Booth, D.B.

    1986-01-01

    An estimate of the sliding velocity and basal meltwater discharge of the Puget lobe of the Cordilleran ice sheet can be calculated from its reconstructed extent, altitude, and mass balance. Lobe dimensions and surface altitudes are inferred from ice limits and flow-direction indicators. Net annual mass balance and total ablation are calculated from relations empirically derived from modern maritime glaciers. An equilibrium-line altitude between 1200 and 1250 m is calculated for the maximum glacial advance (ca. 15,000 yr B.P.) during the Vashon Stade of the Fraser Glaciation. This estimate is in accord with geologic data and is insensitive to plausible variability in the parameters used in the reconstruction. Resultant sliding velocities are as much as 650 m/a at the equilibrium line, decreasing both up- and downglacier. Such velocities for an ice sheet of this size are consistent with nonsurging behavior. Average meltwater discharge increases monotonically downglacier to 3000 m3/sec at the terminus and is of a comparable magnitude to ice discharge over much of the glacier's ablation area. Palcoclimatic inferences derived from this reconstruction are consistent with previous, independently derived studies of late Pleistocene temperature and precipitation in the Pacific Northwest. ?? 1986.

  5. Phased occupation and retreat of the last British-Irish Ice Sheet in the southern North Sea; geomorphic and seismostratigraphic evidence of a dynamic ice lobe

    Science.gov (United States)

    Dove, Dayton; Evans, David J. A.; Lee, Jonathan R.; Roberts, David H.; Tappin, David R.; Mellett, Claire L.; Long, David; Callard, S. Louise

    2017-05-01

    Along the terrestrial margin of the southern North Sea, previous studies of the MIS 2 glaciation impacting eastern Britain have played a significant role in the development of principles relating to ice sheet dynamics (e.g. deformable beds), and the practice of reconstructing the style, timing, and spatial configuration of palaeo-ice sheets. These detailed terrestrially-based findings have however relied on observations made from only the outer edges of the former ice mass, as the North Sea Lobe (NSL) of the British-Irish Ice Sheet (BIIS) occupied an area that is now almost entirely submarine (c.21-15 ka). Compounded by the fact that marine-acquired data have been primarily of insufficient quality and density, the configuration and behaviour of the last BIIS in the southern North Sea remains surprisingly poorly constrained. This paper presents analysis of a new, integrated set of extensive seabed geomorphological and seismo-stratigraphic observations that both advances the principles developed previously onshore (e.g. multiple advance and retreat cycles), and provides a more detailed and accurate reconstruction of the BIIS at its southern-most extent in the North Sea. A new bathymetry compilation of the region reveals a series of broad sedimentary wedges and associated moraines that represent several terminal positions of the NSL. These former still-stand ice margins (1-4) are also found to relate to newly-identified architectural patterns (shallow stacked sedimentary wedges) in the region's seismic stratigraphy (previously mapped singularly as the Bolders Bank Formation). With ground-truthing constraint provided by sediment cores, these wedges are interpreted as sub-marginal till wedges, formed by complex subglacial accretionary processes that resulted in till thickening towards the former ice-sheet margins. The newly sub-divided shallow seismic stratigraphy (at least five units) also provides an indication of the relative event chronology of the NSL. While there

  6. Evolution of the eastern part of the Kuusamo Ice Lobe, based on geomorphological interpretation of high-resolution LiDAR data

    Directory of Open Access Journals (Sweden)

    P. Sarala

    2017-12-01

    Full Text Available In this article, we present new glacial geomorphological data from the eastern part of the Kuusamo Ice Lobe (KIL in eastern Finland. The focus is on glacial lineations (about 9000 individual features and interpretation of ice lobe evolution based on streamlined erosional and depositional formations, hummocky and ribbed moraines and glaciofluvial formations. Glacial geomorphological mapping was performed based on interpretation and classification of LiDAR data according to the Geological Survey of Finland’s new Glacier Dynamic database. The results revealed that modern surficial deposits were formed during three different ice flow phases. The oldest remains are seen as occasional NW-SE megalineations and unclassified glacially lineated terrains and erosional valleys representing the Middle Weichselian glaciation. The younger morphologies were formed from the two overlapping drumlin fields of the Tuoppajärvi and Kuusamo ice flow phases, with origins in the Late Weichselian deglaciation. Analysis of different erosional and depositional formation patterns was used to separate ice flow phases and estimate the evolution, subglacial conditions and mass balance of KIL during the last deglaciation. The morphological interpretation revealed that the Tuoppajärvi ice flow stage was large and homogeneous, while the later Kuusamo ice flow stage was more concentrated, narrower and heterogeneous, following a fan-type pattern that is also emphasised by the meltwater channel systems, including both erosional and depositional features. Furthermore, on both margins (northern and southern, part of the ice masses formed stagnant areas. The length of the lineations also indicates both glacier flow velocity and transport distances, which in the case of megalineations and drumlins are longer than in the fluted terrain. Ribbed moraines in the western (core part of KIL indicate a very different depositional environment relating to strong quarrying and short transport

  7. Glacial Lake Pickering: stratigraphy and chronology of a proglacial lake dammed by the North Sea Lobe of the British-Irish Ice Sheet

    OpenAIRE

    Evans, David J.A.; Bateman, Mark D.; Roberts, David H.; Medialdea, Alicia; Hayes, Laura; Duller, Geoff A.T.; Fabel, Derek; Clark, Chris D.

    2016-01-01

    We report the first chronology, using four new optically stimulated luminescence dates, on the sedimentary record of Glacial Lake Pickering, dammed by the North Sea Lobe of the British–Irish Ice Sheet during the Dimlington Stadial (24–11 ka cal BP). Dates range from 17.6 ± 1.0 to 15.8 ± 0.9 ka for the sedimentation of the Sherburn Sands at East Heslerton, which were formed by multiple coalescing alluvial fans prograding into the falling water levels of the lake and fed by progressively larger...

  8. Multichannel surface clutter suppression: East Antarctica P-band SAR ice sounding in the presence of grating lobes

    DEFF Research Database (Denmark)

    Bekaert, David; Gebert, Nicolas; Lin, Chung-Chi

    2014-01-01

    with the European Space Agency's P-band POLarimetric Airborne Radar Ice Sounder (POLARIS). The 4 m long antenna of POLARIS enables simultaneous reception of up to four across-track channels. It was operated in 2011 over Antarctica at a high flight altitude of 3200 m. Different coherent weighting techniques...

  9. El fin de la tierra

    OpenAIRE

    Benitez Peña, Frank

    2014-01-01

    Ana Faura, una representante de una asociación de desplazados, desea recuperar la tierra que le fue arrebatada para enterrar allí los restos óseos de su esposo asesinado y volver a una vida que añora. En su propósito deberá enfrentarse no solo a amenazas de muerte en contra suya y de su único hijo sino a la necesidad de perdonar a los victimarios para lograr un verdadero retorno.

  10. La Memoria De Nuestra Tierra: Colorado

    Science.gov (United States)

    Baca, Judy

    2005-01-01

    La Memoria de Nuestra Tierra combines a meticulously hand-painted landscape with historic photographs in a seamless blend imprinted on the holographic-like surface of a metallic coated substrate. The mural for the Denver International Airport, entitled La Memoria de Nuestra Tierra is a breakthrough in digital murals, printed digitally on a…

  11. Construcciones a base de tierra

    Directory of Open Access Journals (Sweden)

    Alvarez Alonso, Marina

    1984-11-01

    oriented towards dissipating possible prejudices which exist with regard to earthen constructions.Trabajo realizado y basado en las nuevas posibilidades de las construcciones con tierra, una vez considerado su interés en épocas anteriores y las nuevas posibilidades que ofrece ante la crítica impuesta por la crisis de la energía. Se hacen consideraciones sobre las necesidades de vivienda previstas hasta el año 2000 y otros parámetros que vuelven a ser importantes al confrontarlos económicamente con los materiales industrializados, sistemas de construcción, soluciones orientadas a los países en vías de desarrollo, etc. Continúa el trabajo con las primeras vías de experimentación práctica desarrolladas por el equipo de trabajo de viviendas de bajo coste orientadas a la búsqueda y promoción de recursos locales y abundantes como el material tierra, vías de experimentación que comienzan con el conocimiento por el equipo de técnicas y materiales durante el curso realizado en Ciadueña (Soria. Se describen aspectos técnicos del material tierra desarrollados paralelamente a la experiencia práctica inicial y orientada a la elección idónea de los componentes, una vez confrontada la información bibliográfica relacionada con el tema. Entre las consideraciones técnicas se llega a una exposición más exhaustiva sobre: 1 Las técnicas existentes: ladrillos de adobe, tierra apisonada (tapial, etc. 2 Porcentajes idóneos de los componentes para la elección de los materiales preferibles en cada una de las técnicas anteriores. 3 Consideraciones de los aspectos físicos y mecánicos de la maquinaria existente y en experimentación, así como de las posibilidades respecto a su puesta en obra, costes comparativos, etc. 4 Estudio de las posibilidades para mejorar las características del material tierra mediante diferentes técnicas de estabilización (compactación y correcciones granulométricas, estabilizantes fisicoquímicos, betunes, productos

  12. Bloque de tierra comprimida como material constructivo

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    Óscar Javier Gutiérrez Junco

    2011-07-01

    Full Text Available La construcción con tierra es poco usada en la actualidad debido a la falta de difusión e investigación, y a que es relacionada con la pobreza; por ende, se desaprovechan muchas de sus ventajas, como la abundancia demateria prima, la localización, la disponibilidad, el reciclaje, la producción sin consumo de energía (calorífica, el bajo costo y la resistencia –con un adecuado estudio del material tierra, de la estructuración y del suelo de fundación–; otras de sus ventajas son el aislamiento térmico y acústico. Con el paso del tiempo se han mejorado las técnicas constructivas con tierra, realizando estabilizaciones e implementando el uso de maquinaria y herramienta mecánica para elaborar bloques de tierra comprimida, y así facilitar el trabajo y obtener mayor rendimiento. Este artículo presenta la tierra como material constructivo, las técnicas o sistemas constructivos, los bloques de tierra comprimida (BTC y algunos ensayos realizados a estos bloques.

  13. Subglacial hydrology of the lake district ice lobe during the Younger Dryas (ca. 12 500 - 11 600 years ago) in the Kylaeniemi area, SE Finland

    Energy Technology Data Exchange (ETDEWEB)

    Lunkka, J. P.; Moisio, K.; Vainio, A. [Univ. of Oulu (Finland)

    2013-07-15

    It is essential to gain knowledge on the subglacial hydrological conditions at the glacier bed / bedrock interface when assessing how bedrock fracture zones affect subglacial melt water flow and in which subglacial zones pressurized and oxygen-rich melt water penetrates into the bedrock fracture systems. In the warm-based glacier zones, a part of subglacial melt water will penetrate deep into the fracture systems although the major part of melt water is drained to and beyond the ice margin via subglacial tunnel networks especially in the areas where ice is flowing on the crystalline bedrock. During the last deglaciation phase of the former Scandinavian Ice Sheet, glaciofluvial accumulations were deposited and these sediment accumulations are highly important when picturing the subglacial hydrology of different ice streams during deglaciation in the crystalline bedrock area. The aim of the present work was to map the bedrock fracture zones in the Kylaeniemi area and to shed light on the subglacial hydrology of the Scandinavian Ice Sheet's Lake District Ice Stream that occupied the Kylaeniemi area during the Younger Dryas between ca. 12 500 - 11 600 years ago. The special emphasis within this general aim was to study the relationship between bedrock fracture zones and the routes of subglacial drainage paths. The methods used to map and study bedrock fracture zones and subglacial drainage paths included remotes sensing methods, field observations, ground penetrating radar (GPR) investigations and GIS-based reconstructions. Conventional geological field methods aided by the GPR-method were also used to map bedrock exposures and their structures and to define the type of glaciofluvial sediments and glaciofluvial landform associations. Two main fracture zone sets occur in the study area. The most prominent bedrock fracture zone set trends NW-SE while the other, less prominent fracture zone set is aligned in NE-SW direction. The majority of the minor joint sets in

  14. Subglacial hydrology of the lake district ice lobe during the Younger Dryas (ca. 12 500 - 11 600 years ago) in the Kylaeniemi area, SE Finland

    International Nuclear Information System (INIS)

    Lunkka, J. P.; Moisio, K.; Vainio, A.

    2013-07-01

    It is essential to gain knowledge on the subglacial hydrological conditions at the glacier bed / bedrock interface when assessing how bedrock fracture zones affect subglacial melt water flow and in which subglacial zones pressurized and oxygen-rich melt water penetrates into the bedrock fracture systems. In the warm-based glacier zones, a part of subglacial melt water will penetrate deep into the fracture systems although the major part of melt water is drained to and beyond the ice margin via subglacial tunnel networks especially in the areas where ice is flowing on the crystalline bedrock. During the last deglaciation phase of the former Scandinavian Ice Sheet, glaciofluvial accumulations were deposited and these sediment accumulations are highly important when picturing the subglacial hydrology of different ice streams during deglaciation in the crystalline bedrock area. The aim of the present work was to map the bedrock fracture zones in the Kylaeniemi area and to shed light on the subglacial hydrology of the Scandinavian Ice Sheet's Lake District Ice Stream that occupied the Kylaeniemi area during the Younger Dryas between ca. 12 500 - 11 600 years ago. The special emphasis within this general aim was to study the relationship between bedrock fracture zones and the routes of subglacial drainage paths. The methods used to map and study bedrock fracture zones and subglacial drainage paths included remotes sensing methods, field observations, ground penetrating radar (GPR) investigations and GIS-based reconstructions. Conventional geological field methods aided by the GPR-method were also used to map bedrock exposures and their structures and to define the type of glaciofluvial sediments and glaciofluvial landform associations. Two main fracture zone sets occur in the study area. The most prominent bedrock fracture zone set trends NW-SE while the other, less prominent fracture zone set is aligned in NE-SW direction. The majority of the minor joint sets in

  15. Evidence for stagnation of the Harvard sublobe (Lake Michigan lobe) in Northeastern Illinois, U.S.A., from 24 000 to 17 600 BP and subsequent tundra-like ice-marginal paleoenvironments from 17 600 to 15 700 BP

    Science.gov (United States)

    Curry, B. Brandon; Yansa, C.H.

    2004-01-01

    Glacial deposits of the last glaciation associated with the Harvard sublobe (Lake Michigan lobe) in northeastern Illinois, U.S.A., occur between sediment with dateable organics. The lower organics include fragments of Picea sp. as young as 24 000 ?? 270 BP. The supraglacial organics occur sparsely in laminated silt and fine sand in landforms that are positioned relatively high on the landscape, such as deposits from ice-walled lakes. These terrestrial organics yield ages that are 2500 to 1300 14C years older than organics at the base of sediment successions in nearby kettle basins. Basal 14C ages from four upland sites range from 17 610 ?? 270 to 16 120 ?? 80 BP. Our revised time-distance diagram of the Harvard sublobe now reflects a period of stagnation from 24 000 to about 17 600 BP. The supraglacial lacustrine silt yielded plant macrofossil assemblages of primarily tundra plants, including Salix herbacea and Dryas integrifolia. These plants likely grew in supraglacial and ice-marginal environments. The ostracode fauna include Cytherissa lacustris and Limnocythere friabilis. Geomorphic relations and ostracode ecology indicate that more than 17 m of ice buttressed some of the supraglacial lakes.

  16. Aquilo que nomeia lei: a Madre Tierra

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    Cristina Zanella Rodrigues

    2017-11-01

    Full Text Available Este texto é sustentado teoricamente na Análise do Discurso de viés pêcheuxtiano e tem por corpus dois textos legais: a Ley de Derechos de La Madre Tierra (Ley nº 71/2010 e a Ley Marco de La Madre Tierra y Desarrollo Integral para Vivir Bien (Ley nº 300/2012 aprovadas na Bolívia. A irrupção da Madre Tierra como nome de lei faz ecoar, do lugar da voz dos povos originários, a memória cosmovisionária como discurso da resistência contra o silenciamento de uma história.  Ao atentar para o processo de subjetivação e os ruídos que este acontecimento pode ocasionar, há por objetivo analisar que efeitos de sentido e deslocamentos teóricos são produzidos a partir das formas de nomear, designar, referenciar, subjetivar a Madre Tierra na sua materialização linguístico-discursiva num texto legal. E como se podem operar os conceitos de falta, excesso e estranhamento (ERNST, 2009 no trabalho de análise do nome que nomeia uma lei.

  17. Ecologia de las lombrices de tierra

    Science.gov (United States)

    Grizelle Gonzalez

    2014-01-01

    De los organismos de suelo, las lombrices de tierra son las mas conocidas y a menudo son consideradas las mas importantes por su influencia en el funcionamiento de ecosistemas de suelo (Hendriz y Bohlen, 2002). Tienen un efecto significativo en la estructura del suelo, el ciclo de nutrimentos y ls productividad de las cosechas. En terminos de biomasa, generalmente...

  18. The MIS 3 maximum of the Torres del Paine and Última Esperanza ice lobes in Patagonia and the pacing of southern mountain glaciation

    Science.gov (United States)

    García, Juan-Luis; Hein, Andrew S.; Binnie, Steven A.; Gómez, Gabriel A.; González, Mauricio A.; Dunai, Tibor J.

    2018-04-01

    The timing, structure and termination of the last southern mountain glaciation and its forcing remains unclear. Most studies have focused on the global Last Glacial Maximum (LGM; 26.5-19 ka) time period, which is just part of the extensive time-frame within the last glacial period, including Marine Isotope Stages 3 and 4. Understanding the glacial fluctuations throughout the glacial period is a prerequisite for uncovering the cause and climate mechanism driving southern glaciation and the interhemispheric linkages of climate change. Here, we present an extensive (n = 65) cosmogenic 10Be glacier chronology derived from moraine belts marking the pre-global LGM extent of the former Patagonian Ice Sheet in southernmost South America. Our results show the mountain ice sheet reached its maximum extent at 48.0 ± 1.8 ka during the local LGM, but attained just half this extent at 21.5 ± 1.8 ka during the global LGM. This finding, supported by nearby glacier chronologies, indicates that at orbital time scales, the southern mid-latitude glaciers fluctuated out-of-phase with northern hemisphere ice sheets. At millennial time-scales, our data suggest that Patagonian and New Zealand glaciers advanced in unison with cold Antarctic stadials and reductions in Southern Ocean sea surface temperatures. This implies a southern middle latitudes-wide millennial rhythm of climate change throughout the last glacial period linked to the north Atlantic by the bipolar seesaw. We suggest that winter insolation, acting alongside other drivers such as the strength and/or position of the southern westerlies, controlled the extents of major southern mountain glaciers such as those in southernmost South America.

  19. The architecture of the extremes cultural landscapes in Tierra del Fuego

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    Eugenio Garcés Feliú

    2010-03-01

    Full Text Available This paper aims to analyze the relevance of applying the notion of extreme cultural landscape to Tierra del Fuego, as a complementary category to those defined by Unesco. It states that in Chile there are anumber of territories at the margins –in the end, along the border– that have been built as landscapes, specifics and concretes, where the exploitation of natural resources has proved profitable and the building of human settlements as been allowed. This is the case of Tierra del Fuego, considered as a landscape and as a resource, according to Gregotti and Sola-Morales, that has been formed by a human process on the geographical support of Tierra del Fuego, and owes its existence to a process that transformed this territory into a product, placed south of the ice fields, southeast of the Strait of Magellan, in the confines of America, between south latitudes 52 and 55 degrees. On the other hand, reading the area in terms of palimpsest, according to Corboz, brings out several layers to form the extreme landscapes in Tierra del Fuego, considering some key issues including: the nomination of Magellan as extreme and special area by Cideze; the geographical context of Tierra del Fuego, as the exceptional finish of Patagonia and the gateway to Antarctica; the important collection of narratives and maps bequeathed by European explorers who recognized it; the rich cultural legacy of the aboriginal sélknam; and the human settlements, which emerged at the late nineteenth century, setting some recognizable and typical landscapes. In this way, we argued that the extreme cultural landscapes in Tierra del Fuego have been formed in the manner of overlapping layers, like a palimpsest, in a construction that transcends the physical territory, to settle in the Western cultural fantasy as an imaginary of that remote boundary.

  20. Frontal Lobe Seizures

    Science.gov (United States)

    ... cause of frontal lobe epilepsy remains unknown. Complications Status epilepticus. Frontal lobe seizures tend to occur in clusters and may provoke a dangerous condition called status epilepticus — in which seizure activity lasts much longer than ...

  1. Comprobaciones resistentes de elementos constructivos de tierra

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    Estrada, Enrique

    1986-11-01

    Full Text Available This work has the purpose to compare, by means of different tests on adobe bricks and masonry, the obtained resistant properties and those of other similar works carried out in countries having a wide tradition and knowledge about earth as construction material. Elements (adobe bricks and blocks have been tested to compression and bending, and masonry made of those elements to compression and diagonal compression.El presente trabajo pretende comparar, por medio de distintos ensayos sobre elementos y fábricas de mampostería de tierra, las propiedades resistentes obtenidas con las de otros trabajos similares realizados en países con dilatada tradición y conocimiento de la tierra como material de construcción. Se han ensayado elementos (adobes y bloques a compresión y flexotracción y fábricas formadas por conjuntos de los mismos a compresión y a compresión diagonal.

  2. A Curious Lobe

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    Andréa Chabot-Naud

    2011-01-01

    Full Text Available A case of azygos lobe is presented. An azygos lobe is an accessory lobe of the lung that may occasionally be confused with a pathological process such as a bulla, lung abscess or neoplasm. Its pathogenesis is discussed, as are the characteristic x-ray features that enable an accurate diagnosis.

  3. Tierra Caliente, Michoacán

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    C. I. Villa

    2008-01-01

    Full Text Available Los sistemas de producción ganaderos de la región de Tierra Caliente están vinculados al manejo agrosilvopastoril, aprovechando una amplia gama de recursos forrajeros naturales, siendo las familias quienes conducen la administración y aprovechamiento de dichos recursos. Se buscó definir las características, recursos forrajeros aprovechables e insumos alimenticios, estimando su calidad nutricional, con el fin de encontrar estrategias de alimentación de ganado que reduzcan al mínimo el uso de insumos externos al interior de las unidades productivas. Se trabajó en comunidades del municipio de Tuzantla, en la región de Tierra Caliente del estado de Michoacán. El método incluye la recolección de información por medio de encuestas aplicadas a productores campesinos, durante el ciclo productivo 2007. Se analizaron de 200 a 300 g de 41 muestras de alimentos con el método de Wendee, para analizar su composición química. Se encontró que para la región de Tierra Caliente existe un sistema de producción bovina de mediana escala, semi-estabulado y trashumante que, en promedio, tiene 250 a 260 ha y 86 cabezas de ganado destinado a la producción de carne y pie de cría, y que producen 9.2 l/vaca/día; con esta leche se elabora queso a razón de 1kg de queso por cada 10 litros de leche. Se identificó, también, el uso de seis ingredientes fundamentales que componen dos dietas básicas, cuya composición química detectada fue de 10.2- 13.9% (PC, 7.9-11.8% (FC, 62.8-67.9% (ELN, 1.4-5% (EE y 1.9-8.8% (cenizas. Por tanto, se concluye que los ganaderos cubren los requerimientos nutricionales con base en el alto uso de concentrados, dejando los forrajes para satisfacer las necesidades de consumo de su ganado. Por esto, se requiere establecer un sistema de balanceo de raciones que permita optimizar los recursos

  4. El recurso tierra en Costa Rica

    Directory of Open Access Journals (Sweden)

    Floria Bertsch

    2006-01-01

    Full Text Available En este artículo se presenta un análisis sistemático de la evolución del recurso tierra durante los últimos 10 años, desde diferentes perspectivas: las instituciones involucradas en su manejo, su uso actual y potencial, la actividad agropecuaria que sustenta dicho recurso a través de diferentes mundos agrícolas, y algunas otras opciones de agricultura sostenible que han surgido recientemente como es la agricultura orgánica. También se analiza el urbanismo, como aquella presión que efectúa la población sobre el recurso, y se discuten algunas alternativas de conservación planteadas a nivel nacional. Como conclusiones de la autora, en términos generales, el tema adolece de falta de información confiable desde hace 20 años, hay una clara tendencia al paso de la tierra de pequeños a más grandes propietarios y un incremento en la “peonización” a partir de la pérdida de la propiedad. El país se dirige hacia una clara dependencia de la compra en mercados extranjeros para la alimentación básica, a pesar de la existencia de nuevas opciones tecnológicas. Existen avances importantes en legislación pero aún están a nivel de papel y en términos urbanísticos, la presión social vence el ordenamiento territorial.

  5. OCCIPITAL LOBE SYNDROME

    OpenAIRE

    Shahdevi Nandar Kurniawan

    2016-01-01

    The ability to recognize objects and words is not just depend on the integrity of visual pathway and primary vision area on cerebral cortex (Brodmann area 17), but also secondary vision area 18 and tertiary vision area 19 on occipital lobe. Lesion in occipital lobe could disturb of human visual function such as visual field defects, inability to recognize colors, inability to recognize words, visual hallucinations and illusions, occipital lobe epilepsy, and Anton’s syndrome. Some causes of oc...

  6. Frontal lobe function in temporal lobe epilepsy

    Science.gov (United States)

    Stretton, J.; Thompson, P.J.

    2012-01-01

    Summary Temporal lobe epilepsy (TLE) is typically associated with long-term memory dysfunction. The frontal lobes support high-level cognition comprising executive skills and working memory that is vital for daily life functioning. Deficits in these functions have been increasingly reported in TLE. Evidence from both the neuropsychological and neuroimaging literature suggests both executive function and working memory are compromised in the presence of TLE. In relation to executive impairment, particular focus has been paid to set shifting as measured by the Wisconsin Card Sorting Task. Other discrete executive functions such as decision-making and theory of mind also appear vulnerable but have received little attention. With regard to working memory, the medial temporal lobe structures appear have a more critical role, but with emerging evidence of hippocampal dependent and independent processes. The relative role of underlying pathology and seizure spread is likely to have considerable bearing upon the cognitive phenotype and trajectory in TLE. The identification of the nature of frontal lobe dysfunction in TLE thus has important clinical implications for prognosis and surgical management. Longitudinal neuropsychological and neuroimaging studies assessing frontal lobe function in TLE patients pre- and postoperatively will improve our understanding further. PMID:22100147

  7. La temperatura del interior de la tierra

    Directory of Open Access Journals (Sweden)

    Eslava R. Jesús A.

    1993-10-01

    Full Text Available The problem of defining the Earth interior temperature is analized from Heat Flow observations and the acceptance of convection processes in the mantle. Comparative analyses of thermal, adiabatic, and melting point profiles, allow to obtain the optimum temperature profile, wich fits the seismic model of a liquid external core.

    EI problema de definir la temperatura del interior de la Tierra, se analiza a partir de las observaciones del flujo térmico y la aceptación de procesos de convección en el manto.

    Análisis comparativos de perfiles térmicos, adiabáticos y de puntos de fusión, permiten obtener un perfil óptimo de distribución de temperaturas, que además satisface la observación sísmica de un núcleo externo líquido.

  8. Temporal Lobe Seizure

    Science.gov (United States)

    ... functions, including having odd feelings — such as euphoria, deja vu or fear. Temporal lobe seizures are sometimes called ... sudden sense of unprovoked fear or joy A deja vu experience — a feeling that what's happening has happened ...

  9. Polar Ice Caps: a Canary for the Greenland Ice Sheet

    Science.gov (United States)

    Honsaker, W.; Lowell, T. V.; Sagredo, E.; Kelly, M. A.; Hall, B. L.

    2010-12-01

    Ice caps are glacier masses that are highly sensitive to climate change. Because of their hypsometry they can have a binary state. When relatively slight changes in the equilibrium line altitude (ELA) either intersect or rise above the land the ice can become established or disappear. Thus these upland ice masses have a fast response time. Here we consider a way to extract the ELA signal from independent ice caps adjacent to the Greenland Ice Sheet margin. It may be that these ice caps are sensitive trackers of climate change that also impact the ice sheet margin. One example is the Istorvet Ice Cap located in Liverpool Land, East Greenland (70.881°N, 22.156°W). The ice cap topography and the underlying bedrock surface dips to the north, with peak elevation of the current ice ranging in elevation from 1050 to 745 m.a.s.l. On the eastern side of the ice mass the outlet glaciers extending down to sea level. The western margin has several small lobes in topographic depressions, with the margin reaching down to 300 m.a.s.l. Topographic highs separate the ice cap into at least 5 main catchments, each having a pair of outlet lobes toward either side of the ice cap. Because of the regional bedrock slope each catchment has its own elevation range. Therefore, as the ELA changes it is possible for some catchments of the ice cap to experience positive mass balance while others have a negative balance. Based on weather observations we estimate the present day ELA to be ~1000 m.a.s.l, meaning mass balance is negative for the majority of the ice cap. By tracking glacier presence/absence in these different catchments, we can reconstruct small changes in the ELA. Another example is the High Ice Cap (informal name) in Milne Land (70.903°N, 25.626°W, 1080 m), East Greenland. Here at least 4 unconformities in ice layers found near the southern margin of the ice cap record changing intervals of accumulation and ablation. Therefore, this location may also be sensitive to slight

  10. Estado, mercado de tierra urbana e inundaciones en ciudades argentinas

    Directory of Open Access Journals (Sweden)

    Nora Clichevsky

    2006-01-01

    Full Text Available En este trabajo se presentan los resultados de una investigación sobre las relaciones que se establecen entre los mercados de tierra urbana y las inundaciones en ciudades argentinas, en el marco más amplio de la vulnerabilidad urbana. Se pretende despejar incógnitas acerca del papel jugado por el Estado como regulador del mercado en áreas urbanas con vulnerabilidad natural a la inundación y como constructor de defensas contra las inundaciones y acerca de los impactos que han tenido las inundaciones y las obras de defensa contra ellas sobre el mercado de tierra y, por lo tanto, sobre el acceso al suelo urbano por parte de los distintos sectores de la población.

  11. La Arquitectura de tierra es una herencia humana

    Directory of Open Access Journals (Sweden)

    Walter Domínguez Vega

    2010-01-01

    Full Text Available Se aborda el uso de la tierra en la restauración y conservación de la vivienda más antigua de Holguín. Se basa en la tendencia actual para la conservación sostenible de los bienes patrimoniales y culturales que orienta los materiales utilizados en los trabajos de intervención, se detiene sobre la relevancia y alcance histórico cultural del patrimonio edificado en la provincia de Holguín, describe las características constructivas de sus muros de embarrado los morteros utilizados y las dificultades para la conservación de ésta. Propone que se revitalice el uso de la tierra en construcciones de viviendas y menciona las investigaciones arqueológicas históricas en el interior y exterior de la casa.

  12. Saber tradicional, ética de la tierra y sustentabilidad

    Directory of Open Access Journals (Sweden)

    Heyd, Thomas

    2005-06-01

    Full Text Available This is the crucial moment to take on sustainable forms of life, and hence it is now of primary importance to adopt a land ethic that takes into account not only the use value but also the intrinsic value of the beings that make up our natural environment. In this essay I begin by focusing on the obstacles that the development of a land ethic has to face, obstacles that are due to limitations in knowledge and to mistaken assumptions. As a way to resolve these practical difficulties I first point out the existence of our natural inclinations toward the land and life. Furthermore, I propose that the traditional knowledge of those peoples that have lived for extended periods with their environments can serve us as models for the development of a culture of appreciation for the earth and its inhabitants.

    Éste ese! momento crucial para emprender formas de vida sustentables, por lo que resulta esencial adoptar una ética de la tierra que reconozca el valor intrínseco además del valor útil de los seres que pueblan nuestro medio ambiente natural. En este ensayo empiezo enfocando los obstáculos a que se enfrenta el desarrollo de una ética de la tierra, obstáculos que resultan ser el producto de conocimientos limitados y suposiciones equivocadas. En resolución de esas problemáticas prácticas apunto, primero, la existencia de inclinaciones naturales hacia la tierra y la vida. Además propongo que en el saber tradicional de los pueblos que han convivido mucho tiempo con sus espacios tenemos modelos de formas del conocer que nos pueden servir de modelo para llegar a desarrollar una cultura de aprecio de la tierra y de sus habitantes.

  13. Exploraciones Micológicas en Tierra del Fuego Mycological explorations in Tierra del Fuego

    Directory of Open Access Journals (Sweden)

    Irma J. Gamundí

    2007-07-01

    Full Text Available Se narran las expediciones marítimas y terrestres en Tierra del Fuego durante los siglos XIX y XX, desde el punto de vista de la exploración micológica cuyos resultados han sido vertidos en publicaciones, destacando las expediciones argentinas. Contiene mapas con las principales expediciones argentinas. Se hace una evaluación de la diversidad fúngica de acuerdo con los datos previamente analizados, comparando los registros de colección en ambos períodos que indican una duplicación del número total de taxones de 647 especies descriptas en el siglo XIX hasta 1269 en el siglo XX. Simultáneamente se observa una disminución del 50,4 % al 19.7 % en el número de especies nuevas publicadas. Se agrega una lista de coleccionistas y otra del estado de conservación ex situ de especies seleccionadas. Se hace un breve comentario sobre la conservación de hábitats colonizados por hongos que están perturbados por la explotación no sustentable de los recursos naturales.A narration of the leading maritime and terrestrial expeditions in Fuegia during the XIX and XX centuries is approached from the point of view of the mycological exploration and published results on the mycobiota, emphazising the Argentine expeditions. Maps with the itinerary of main Argentine expeditions is given. An evaluation of the fungal diversity according to the previous review is presented, comparing the fungal records during both periods that shows duplication of the total number of taxa from 647 species described in XIX century to 1269 in the XX century. Simultaneously there is a decrease from 50.4 % to 19.7 % in the number of new species published. A list of collectors and a table with the state of ex-situ conservation of selected species is presented. A brief comment is given on conservation of habitats supporting fungal population that are disturbed by unsustainable exploitation of natural resources.

  14. Medial temporal lobe

    International Nuclear Information System (INIS)

    Silver, A.J.; Cross, D.T.; Friedman, D.P.; Bello, J.A.; Hilal, S.K.

    1989-01-01

    To better define the MR appearance of hippocampal sclerosis, the authors have reviewed over 500 MR coronal images of the temporal lobes. Many cysts were noted that analysis showed were of choroid-fissure (arachnoid) origin. Their association with seizures was low. A few nontumorous, static, medial temporal lesions, noted on T2-weighted coronal images, were poorly visualized on T1-weighted images and did not enhance with gadolinium. The margins were irregular, involved the hippocampus, and were often associated with focal atrophy. The lesions usually were associated with seizure disorders and specific electroencephalographic changes, and the authors believe they represented hippocampal sclerosis

  15. Ice Sheets & Ice Cores

    DEFF Research Database (Denmark)

    Mikkelsen, Troels Bøgeholm

    Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known....... The first part concerns time series analysis of ice core data obtained from the Greenland Ice Sheet. We analyze parts of the time series where DO-events occur using the so-called transfer operator and compare the results with time series from a simple model capable of switching by either undergoing...

  16. LUCHA POR LA TIERRA EN EL NORTE DE URUGUAY

    Directory of Open Access Journals (Sweden)

    Gabriel Oyhantçabal Benelli

    2011-12-01

    Full Text Available Este artículo analiza la trayectoria de la lucha por la tierra en Bella Unión, una región característica en Uruguay por la producción de caña de azúcar, a través de los movimientos de clase de sus principales protagonistas: los cortadores de caña sindicalizados en la Unión de Trabajadores Azucareros de Artigas (UTAA. El recorrido histórico hace énfasis en dos períodos históricos diferentes: 1961-1973 y 2005-presente. El primero va desde la fundación del sindicato hasta el golpe militar. Se da en un contexto de auge de la lucha de masas en Uruguay en el cual los trabajadores rurales se organizan en la UTAA levantando, entre otras, la bandera de la Reforma Agraria. El segundo período está marcado por la llegada al gobierno nacional del Frente Amplio, una coalición social-demócrata que reactiva la producción de caña de azúcar en Bella Unión. Este cambio supone una oportunidad para las luchas sociales que la UTAA aprovecha con ocupaciones de tierra favoreciendo un proceso de colonización para los trabajadores rurales. Sin embargo el acceso a la tierra genera nuevas contradicciones, y por tanto nuevos desafíos, por los cambios en la forma de subsunción del trabajo al capital.

  17. Construcción con tierra en el siglo XXI

    Directory of Open Access Journals (Sweden)

    Bestraten, S.

    2011-09-01

    Full Text Available Earthen construction during the 21rst century first decade has resurfaced worldwide as a sustainable, low environmental impact and great expressive material. The research and the number of projects has been increased related to the growth of the associations, institutions, universities and events surrounding this sector. These projects have managed to modernize the traditional techniques of building with earth in order to adapt them to today’s projecting needs, and have been widely recognized for its quality. The aim of this article is to provide a global view on earth construction internationally, providing technical data of its utilization in contemporary architectural projects.

    La construcción con tierra durante la primera década del siglo XXI ha resurgido en todo el mundo como un material con propiedades sostenibles, de bajo impacto ambiental y de gran capacidad expresiva. Se ha experimentado un crecimiento a nivel de proyectos e investigaciones sobre el material relacionado con el aumento de número de asociaciones, instituciones, universidades y eventos alrededor de este sector. Los proyectos actuales han sabido modernizar las técnicas tradicionales de construcción con tierra para adaptarlas a las necesidades proyectuales y constructivas, siendo ampliamente reconocidos por su calidad. El objetivo de este artículo es ofrecer una visión actual sobre la construcción con tierra a nivel internacional, aportando datos técnicos de su utilización en proyectos arquitectónicos contemporáneos.

  18. Sol, Tierra y Luna. Movimientos relativos y sus consecuencias

    Directory of Open Access Journals (Sweden)

    Sebastián Cardenete García

    2011-01-01

    Full Text Available Cuando se pregunta a los estudiantes por la causa de las estaciones suelen responder: "en verano estamos más próximos al Sol y en invierno estamos más lejos del Sol". La persistencia de esta idea y el hecho de su generalización entre los estudiantes y muchos adultos me ha inducido a escribir este artículo, en el cual se trata de explicar, de una forma clara y simple, el motivo de este y otros fenómenos debidos al movimiento de la Luna alrededor de la Tierra y de ésta alrededor del Sol.

  19. Ice, Ice, Baby!

    Science.gov (United States)

    Hamilton, C.

    2008-12-01

    The Center for Remote Sensing of Ice Sheets (CReSIS) has developed an outreach program based on hands-on activities called "Ice, Ice, Baby". These lessons are designed to teach the science principles of displacement, forces of motion, density, and states of matter. These properties are easily taught through the interesting topics of glaciers, icebergs, and sea level rise in K-8 classrooms. The activities are fun, engaging, and simple enough to be used at science fairs and family science nights. Students who have participated in "Ice, Ice, Baby" have successfully taught these to adults and students at informal events. The lessons are based on education standards which are available on our website www.cresis.ku.edu. This presentation will provide information on the activities, survey results from teachers who have used the material, and other suggested material that can be used before and after the activities.

  20. Hepatocellular carcinoma in Riedel's lobe.

    Science.gov (United States)

    Zamfir, R; Braşoveanu, V; Boroş, M; Herlea, V; Popescu, I

    2008-01-01

    We present a rare case of 65-year female with right abdominal mass and abdominal discomfort; a combination of Doppler ultrasonography, computed tomography and laparotomy was utilized to make a diagnosis of tumoral Riedel's lobe. In our case, laparotomy with resection of Riedel's lobe was the proper therapeutical solution.

  1. De vuelta a la concentración de tierras en el Perú

    OpenAIRE

    Arias Nieto, Custodio

    2014-01-01

    En este artículo presento el nuevo proceso de concentración de tierras en el Perú producido en los últimos quince años, teniendo como marco las normas legales del modelo neoliberal. Éstas han permitido la emergencia del latifundio en las mejores tierras que se encuentran en la costa peruana, cuya producción es principalmente para la exportación. Asimismo, las concesiones mineras, petroleras y forestales también vienen conduciendo a un nuevo tipo de concentración de tierras que degrada o destr...

  2. La arquitectura en tierra: Una alternativa para la construcción sostenible

    OpenAIRE

    Gloria Zuleta Roa

    2012-01-01

    La inquietud sobre la sostenibilidad de la arquitectura hecha con tierra se convierte en el punto de partida para escribir este artículo sobre el uso de la tierra como alternativa para realizar construcciones sostenibles. Se inicia con una mirada histórica del uso de la tierra como material de construcción en el mundo y en Colombia; sus características en relación con la sostenibilidad en los procesos constructivos y finalmente su contextualización dentro de las normas que regulan la construc...

  3. La arquitectura en tierra: Una alternativa para la construcción sostenible

    Directory of Open Access Journals (Sweden)

    Gloria Zuleta Roa

    2011-12-01

    Full Text Available La inquietud sobre la sostenibilidad de la arquitectura hecha con tierra se convierte en el punto de partida para escribir este artículo sobre el uso de la tierra como alternativa para realizar construcciones sostenibles. Se inicia con una mirada histórica del uso de la tierra como material de construcción en el mundo y en Colombia; sus características en relación con la sostenibilidad en los procesos constructivos y finalmente su contextualización dentro de las normas que regulan la construcción.

  4. Midiendo el diámetro de la Tierra

    Directory of Open Access Journals (Sweden)

    Sierra Porta, S.

    2008-09-01

    Full Text Available De distintas maneras se han ingeniado interesantes procedimientos para medir el radio de la tierra. Aquí se expone uno con la utilización de muchas técnicas sea formales o no para tal fín. El procedimiento es lo suficientemente sencillo como para que cualquier aficionado pueda repetirlo. No es un nuevo método, pero puede verse como pequeñas variaciones al mismo pudieran dar menos o más errores. El método precisa de tres piedras, una cuerda y una regla, de acuerdo con sus indicaciones, se debe contar también con un cerro desde donde podamos divisar el horizonte desde un lugar despejado en dos direcciones opuestas. La altura ideal de esta colina o promontorio seria de 30 a 300 metros sobre el nivel del mar (fácilmente podría ser desde un edificio; desde ella se divisara claramente una zona despejada. La motivación principal es proporcionar un marco para que los estudiantes en clase diserten acerca de la posibilidad de medier el tamaño de la tierra con argumentos muy sencillos y al alcance de todos. Se estimula de formulación de proyectos para investigación en el aula. Además se considera, en concordancia con las reformas de la educación y la globalización de las ciencias y los conocimientos, como estas actividades pueden acoger distintas disciplinas para un análisis óptimo de los resultados.

  5. Cultural tourism in fragile institutional contexts: project for cultural routes in Tierra del Fuego

    OpenAIRE

    Garcés Feliu, Eugenio

    2012-01-01

    The following paper presents a project of Cultural Routes designed for the Chilean Tierra del Fuego, linked to promoting tourism and boosting the economy, through the development of a specific high standard tourism offer, linked to its natural and cultural heritage, with the purpose of capturing the potential income generation for Chile. The project had as main goal to enhance the competitiveness of the tourism sector of special interests in Tierra del Fuego, a key sector of South...

  6. El nuevo acaparamiento de tierras y las cambiantes dinamicas de la agricultura en el sur de Africa

    OpenAIRE

    Hall, Ruth

    2011-01-01

    El termino 'acaparamiento con fuerza en los ultimos anos para describir el renovado interes de las empresas por la tierra agraria, que se materializado en forma de cerramientos y privatizaciones de tierras a gran escala. Sin embargo, este termino esconde importantes diferencias respecto a la legalidad, la estructura y los resultados de los acuerdos comerciales sobre la tierra, de manera que desvia la atencion respecto al papel desempenado por las elites y los gobernos locales como socios, int...

  7. Acaparamiento de tierras y acumulación global capitalista: aspectos clave en América Latina.

    OpenAIRE

    Landívar, Natalia

    2013-01-01

    El análisis del acaparamiento de la tierra en América Latina está centrado básicamente en dos conceptos: la extranjerización y concentración de la tierra. Por un lado, en varios países como Argentina, Brasil, Uruguay, Paraguay y Guatemala la discusión se ha centrado en la extranjerización de la propiedad de la tierra. Esta se refiere a la adquisición de tierra por actores extranjeros, como gobiernos y corporaciones, así como de individuos, para una variedad de propósitos y de diferentes escal...

  8. Ice Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, atmospheric trace gases, and other aspects of climate and environment derived from ice cores drilled on glaciers and ice...

  9. Ice Cream

    NARCIS (Netherlands)

    Scholten, E.

    2014-01-01

    Ice cream is a popular dessert, which owes its sensorial properties (mouth feel) to its complex microstructure. The microstructure is a result of the combination of the ingredients and the production process. Ice cream is produced by simultaneous freezing and shearing of the ice cream mix, which

  10. Ice targets

    International Nuclear Information System (INIS)

    Pacheco, C.; Stark, C.; Tanaka, N.; Hodgkins, D.; Barnhart, J.; Kosty, J.

    1979-12-01

    This report presents a description of ice targets that were constructed for research work at the High Resolution Spectrometer (HRS) and at the Energetic Pion Channel and Spectrometer (EPICS). Reasons for using these ice targets and the instructions for their construction are given. Results of research using ice targets will be published at a later date

  11. Left lower lobe atelectasis and consolidation following cardiac surgery: the effect of topical cooling on the phrenic nerve

    International Nuclear Information System (INIS)

    Benjamin, J.J.; Cascade, P.N.; Rubenfire, M.; Wajszczuk, W.; Kerin, N.Z.

    1982-01-01

    Retrospective and prospective analyses of chest radiographs of patients following coronary artery bypass surgery were undertaken. Left lower lobe pulmonary infiltrate and/or atelectasis developed in 13 of 40 (32.5%) patients who were operated upon without topical cooling of the heart with ice, and in 77 of 122 (63.1%) patients in one group and 34 of 40 (85.0%) patients in another group who were operated upon with topical cooling of the heart with ice. This difference was highly significant (p<0.001). Of the patients in one group in whom left lower lobe abnormality developed, 69.2% had paralysis or paresis of the left hemidiaphragm. It is evident that application of ice to the phrenic nerve can lead to temporary paralysis of the left leaf of the diaphragm, with subsequent development of left lower lobe pulmonary infiltrate and/or atelectasis

  12. Left lower lobe atelectasis and consolidation following cardiac surgery: the effect of topical cooling on the phrenic nerve

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin, J.J.; Cascade, P.N.; Rubenfire, M.; Wajszczuk, W.; Kerin, N.Z.

    1982-01-01

    Retrospective and prospective analyses of chest radiographs of patients following coronary artery bypass surgery were undertaken. Left lower lobe pulmonary infiltrate and/or atelectasis developed in 13 of 40 (32.5%) patients who were operated upon without topical cooling of the heart with ice, and in 77 of 122 (63.1%) patients in one group and 34 of 40 (85.0%) patients in another group who were operated upon with topical cooling of the heart with ice. This difference was highly significant (p<0.001). Of the patients in one group in whom left lower lobe abnormality developed, 69.2% had paralysis or paresis of the left hemidiaphragm. It is evident that application of ice to the phrenic nerve can lead to temporary paralysis of the left leaf of the diaphragm, with subsequent development of left lower lobe pulmonary infiltrate and/or atelectasis.

  13. Brain SPECT imaging in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Krausz, Y.; Yaffe, S.; Atlan, H.; Cohen, D.; Konstantini, S.; Meiner, Z.

    1991-01-01

    Temporal lobe epilepsy is diagnosed by clinical symptoms and signs and by localization of an epileptogenic focus. A brain SPECT study of two patients with temporal lobe epilepsy, using 99m Tc-HMPAO, was used to demonstrate a perfusion abnormality in the temporal lobe, while brain CT and MRI were non-contributory. The electroencephalogram, though abnormal, did not localize the diseased area. The potential role of the SPECT study in diagnosis and localization of temporal lobe epilepsy is discussed. (orig.)

  14. Temporal Lobe Epilepsy in Children

    Science.gov (United States)

    Nickels, Katherine C.; Wong-Kisiel, Lily C.; Moseley, Brian D.; Wirrell, Elaine C.

    2012-01-01

    The temporal lobe is a common focus for epilepsy. Temporal lobe epilepsy in infants and children differs from the relatively homogeneous syndrome seen in adults in several important clinical and pathological ways. Seizure semiology varies by age, and the ictal EEG pattern may be less clear cut than what is seen in adults. Additionally, the occurrence of intractable seizures in the developing brain may impact neurocognitive function remote from the temporal area. While many children will respond favorably to medical therapy, those with focal imaging abnormalities including cortical dysplasia, hippocampal sclerosis, or low-grade tumors are likely to be intractable. Expedient workup and surgical intervention in these medically intractable cases are needed to maximize long-term developmental outcome. PMID:22957247

  15. Occipital lobe infarctions are different

    OpenAIRE

    Naess, Halvor; Waje-Andreassen, Ulrikke; Thomassen, Lars

    2007-01-01

    Halvor Naess, Ulrikke Waje-Andreassen, Lars ThomassenDepartment of Neurology, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayObjectives: We hypothesized that occipital lobe infarctions differ from infarctions in other locations as to etiology, risk factors and prognosis among young adults.Methods: Location, etiology, risk factors and long-term outcome were evaluated among all young adults 15–49 years suffering from cerebral infarction in Hordaland County, Norw...

  16. Diversity of endosymbiotic Nostoc in Gunnera magellanica from Tierra del Fuego, Chile [corrected].

    Science.gov (United States)

    Fernández-Martínez, M A; de Los Ríos, A; Sancho, L G; Pérez-Ortega, S

    2013-08-01

    Global warming is causing ice retreat in glaciers worldwide, most visibly over the last few decades in some areas of the planet. One of the most affected areas is the region of Tierra del Fuego (southern South America). Vascular plant recolonisation of recently deglaciated areas in this region is initiated by Gunnera magellanica, which forms symbiotic associations with the cyanobacterial genus Nostoc, a trait that likely confers advantages in this colonisation process. This symbiotic association in the genus Gunnera is notable as it represents the only known symbiotic relationship between angiosperms and cyanobacteria. The aim of this work was to study the genetic diversity of the Nostoc symbionts in Gunnera at three different, nested scale levels: specimen, population and region. Three different genomic regions were examined in the study: a fragment of the small subunit ribosomal RNA gene (16S), the RuBisCO large subunit gene coupled with its promoter sequence and a chaperon-like protein (rbcLX) and the ribosomal internal transcribed spacer (ITS) region. The identity of Nostoc as the symbiont was confirmed in all the infected rhizome tissue analysed. Strains isolated in the present study were closely related to strains known to form symbioses with other organisms, such as lichen-forming fungi or bryophytes. We found 12 unique haplotypes in the 16S rRNA (small subunit) region analysis, 19 unique haplotypes in the ITS region analysis and 57 in the RuBisCO proteins region (rbcLX). No genetic variability was found among Nostoc symbionts within a single host plant while Nostoc populations among different host plants within a given sampling site revealed major differences. Noteworthy, interpopulation variation was also shown between recently deglaciated soils and more ancient ones, between eastern and western sites and between northern and southern slopes of Cordillera Darwin. The cell structure of the symbiotic relationship was observed with low-temperature scanning

  17. Formas de tierra y clases de pendiente del departamento de Cusco: informe ejecutivo

    OpenAIRE

    Instituto Nacional de Recursos Naturales. Dirección General de Estudios y Proyectos

    2000-01-01

    Muestra la evaluación de las formas de tierra y clases de pendiente de la región sierra del departamento de Cusco. El objetivo principal es presentar de manera esquemática el conjunto de formas de tierra, clases de pendiente dominante, sus diferencias morfoclimáticas y evolutivas, así como la identificación de las principales acciones erosivas que actualmente puedan significar riesgos a las actividades humanas, o a coadyuvar al deterioro generalizado del medio. El documento ha sido elaborado ...

  18. Formas de tierra y clases de pendiente del departamento de Amazonas: informe ejecutivo

    OpenAIRE

    Instituto Nacional de Recursos Naturales. Dirección General de Estudios y Proyectos

    2000-01-01

    Muestra la evaluación de las formas de tierra y clases de pendiente de la región sierra del departamento de Amazonas. El objetivo principal es presentar de manera esquemática el conjunto de formas de tierra, clases de pendiente dominante, sus diferencias morfoclimáticas y evolutivas, así como la identificación de las principales acciones erosivas que actualmente puedan significar riesgos a las actividades humanas, o a coadyuvar al deterioro generalizado del medio. El documento ha sido elabora...

  19. Formas de tierra y clases de pendiente del departamento de Ica: informe ejecutivo

    OpenAIRE

    Instituto Nacional de Recursos Naturales. Dirección General de Estudios y Proyectos

    2000-01-01

    Abarca la evaluación de las formas de tierra y clases de pendiente de la región sierra del departamento de Ica. El objetivo principal es brindar de manera esquemática el conjunto de formas de tierra, clases de pendiente dominante, sus diferencias morfoclimáticas y evolutivas, así como la identificación de las principales acciones erosivas que actualmente puedan significar riesgos a las actividades humanas, o a coadyuvar al deterioro generalizado del medio. El documento ha sido elaborado en el...

  20. Formas de tierra y clases de pendiente del departamento de Arequipa: informe ejecutivo

    OpenAIRE

    Instituto Nacional de Recursos Naturales. Dirección General de Estudios y Proyectos

    1999-01-01

    Abarca la evaluación de las formas de tierra y clases de pendiente de la región sierra del departamento de Arequipa. El objetivo principal es mostrar de manera esquemática el conjunto de formas de tierra, clases de pendiente dominante, sus diferencias morfoclimáticas y evolutivas, así como la identificación de las principales acciones erosivas que actualmente puedan significar riesgos a las actividades humanas, o a coadyuvar al deterioro generalizado del medio. El documento ha sido elaborado ...

  1. The architecture of the extremes cultural landscapes in Tierra del Fuego

    OpenAIRE

    Garcés Feliú, Eugenio

    2010-01-01

    This paper aims to analyze the relevance of applying the notion of extreme cultural landscape to Tierra del Fuego, as a complementary category to those defined by Unesco. It states that in Chile there are anumber of territories at the margins –in the end, along the border– that have been built as landscapes, specifics and concretes, where the exploitation of natural resources has proved profitable and the building of human settlements as been allowed. This is the case of Tierra del Fuego, con...

  2. A Geochemical and Sedimentary Record of High Southern Latitude Holocene Climate Evolution from Lago Fagnano, Tierra del Fuego

    Energy Technology Data Exchange (ETDEWEB)

    Moy, C M; Dunbar, R B; Guilderson, T P; Waldmann, N; Mucciarone, D A; Recasens, C; Austin, J A; Anselmetti, F S

    2010-11-19

    Situated at the southern margin of the hemispheric westerly wind belt and immediately north of the Antarctic Polar Frontal zone, Tierra del Fuego is well-positioned to monitor coupled changes in the ocean-atmosphere system of the high southern latitudes. Here we describe a Holocene paleoclimate record from sediment cores obtained from Lago Fagnano, a large lake in southern Tierra del Fuego at 55{sup o}S, to investigate past changes in climate related to these two important features of the global climate system. We use an AMS radiocarbon chronology for the last 8,000 years based on pollen concentrates, thereby avoiding contamination from bedrock-derived lignite. Our chronology is consistent with a tephrochronologic age date for deposits from the middle Holocene Volcan Hudson eruption. Combining bulk organic isotopic ({delta}{sup 13}C and {delta}{sup 15}N) and elemental (C and N) parameters with physical sediment properties allow us to better understand sediment provenance and transport mechanisms and to interpret Holocene climate and tectonic change during the last 8,000 years. Co-variability and long-term trends in C/N ratio, carbon accumulation rate, and magnetic susceptibility reflect an overall Holocene increase in the delivery of terrestrial organic and lithogenic material to the deep eastern basin. We attribute this variability to westerly wind-derived precipitation. Increased wind strength and precipitation in the late Holocene drives the Nothofagus forest eastward and enhances run-off and terrigenous inputs to the lake. Superimposed on the long-term trend are a series of abrupt 9 negative departures in C/N ratio, which constrain the presence of seismically-driven mass flow events in the record. We identify an increase in bulk {delta}{sup 13}C between 7,000 and 5,000 cal yr BP that we attribute to enhanced aquatic productivity driven by warmer summer temperatures. The Lago Fagnano {delta}{sup 13}C record shows similarities with Holocene records of sea surface

  3. Sea Ice

    Science.gov (United States)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.

    2013-01-01

    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  4. Un congreso de fisica estudia la composicion de las capas de la tierra

    CERN Multimedia

    2003-01-01

    "El Congreso de Internacional de Neutrinos, que ayer comenzo en el Jardin Botanico de Valencia, aborda, entre otros aspectos, la composicion y el perfil tomografico de las distintas capas de estratos del interior de la Tierra, segun informo a Efe el profesor Jose Furtado Valle" (1/2 page).

  5. La Carta de la Tierra en educación obligatoria desde una perspectiva internacional

    Directory of Open Access Journals (Sweden)

    Eva Francisca Hinojosa-Pareja

    2014-01-01

    Full Text Available La Carta de la Tierra surge como iniciativa de la sociedad civil en el año 2000. Desde su comienzo, es avalada por instituciones y organizaciones internacionales como la Unesco, que apoyó su contenido en 2003, e incorporada como instrumento educativo en proyectos de aplicación internacional como la “Década de la Educación para el Desarrollo Sostenible (2005-2014”, promovida por Naciones Unidas. Este artículo analiza distintas experiencias internacionales que utilizan la Carta de la Tierra como elemento de innovación en el ámbito de la educación obligatoria (infantil, primaria y secundaria. Una década después de la publicación de la Carta de la Tierra, y a través del análisis del contenido de estas experiencias, pretendemos hacer balance del camino recorrido, del grado de compromiso asumido desde el ámbito educativo, y favorecer el diálogo y la progresiva toma de conciencia sobre la Carta de la Tierra y su relevancia a nivel educativo.

  6. Relaciones entre la presencia de tierra y la supervivencia en serpientes de coral mantenidas en cautiverio

    OpenAIRE

    Reynoso, H.; Bucher, Enrique; Merlini, H. O.

    1985-01-01

    Teniendo en cuenta las particularidades de la especie Micrurus frontalis pyrrhocryptus (coral) en lo referente a su comportamiento semifosorial, hemos considerado conveniente relacionar distintos aspectos biológicos de la especie tales como longevidad, peso y producción de veneno, con la disponibilidad de tierra en recipientes y exposición a la luz.

  7. Los Takanas: el acceso a la tierra y los recursos naturales (1950-2003.

    Directory of Open Access Journals (Sweden)

    Zulema Lehm Ardaya

    2010-01-01

    uso comercial de diferentes especies naturales. El artículo discute la adaptación de los takanas a los desafíos y tendencias del uso de los recursos naturales en sistemas de acceso comunitario a la tierra.

  8. IMPACTOS DEL CAMBIO DE USO DE LA TIERRA EN LA MICROCUENCA MEMBRILLO, MANABÍ, ECUADOR

    Directory of Open Access Journals (Sweden)

    Alberto Hernández Jiménez

    2013-12-01

    Full Text Available El cambio de uso de la tierra, sobre todo el cambio de tierras forestales a tierras cultivadas, es una de las prácticas que mayor impacto ha tenido en la degradación de los suelos en el mundo y que ha provocado, en gran parte, la emisión de CO2 a la atmósfera. Por esto se hace necesario evaluar los cambios que han tenido las propiedades de los suelos por los diferentes ecosistemas, para de esta forma, tomar las medidas de mejoramiento y conservación de los suelos. En este trabajo, se estudia por primera vez, el cambio de algunas propiedades de los suelos de las partes medias y bajas de la microcuenca Membrillo (provincia de Manabí, Ecuador. Esta microcuenca presenta un relieve alomado, premontañoso, en la cual predominan bosques primarios y secundarios y plantaciones de cacao, pastizales y cultivos como el maíz en su parte baja. Los suelos son Feozems, Cambisoles y Fluvisoles y se presentan los resultados sobre cambios en sus características morfológicas (color, tipo de estructura, espesor de los horizontes A y B, las pérdidas de carbono orgánico y el cambio en la densidad aparente del suelo, provocado por el cambio de uso de la tierra.

  9. Review of Los nuevos amos de la tierra. Land Grabbing (Liberti, 2015

    Directory of Open Access Journals (Sweden)

    Germán Ignacio Ochoa

    2017-01-01

    Full Text Available Stefano Liberti. 2015. Los nuevos amos de la tierra. Land Grabbing. Bogotá: Penguin Random House Grupo Editorial. 250 pp. ISBN: 9788430616886. [Título original en italiano: Land Grabbing. Come il mercato delle terre crea il nuovo colonialismo].

  10. Occipital lobe seizures and epilepsies.

    Science.gov (United States)

    Adcock, Jane E; Panayiotopoulos, Chrysostomos P

    2012-10-01

    Occipital lobe epilepsies (OLEs) manifest with occipital seizures from an epileptic focus within the occipital lobes. Ictal clinical symptoms are mainly visual and oculomotor. Elementary visual hallucinations are common and characteristic. Postictal headache occurs in more than half of patients (epilepsy-migraine sequence). Electroencephalography (EEG) is of significant diagnostic value, but certain limitations should be recognized. Occipital spikes and/or occipital paroxysms either spontaneous or photically induced are the main interictal EEG abnormalities in idiopathic OLE. However, occipital epileptiform abnormalities may also occur without clinical relationship to seizures particularly in children. In cryptogenic/symptomatic OLE, unilateral posterior EEG slowing is more common than occipital spikes. In neurosurgical series of symptomatic OLE, interictal EEG abnormalities are rarely strictly occipital. The most common localization is in the posterior temporal regions and less than one-fifth show occipital spikes. In photosensitive OLE, intermittent photic stimulation elicits (1) spikes/polyspikes confined in the occipital regions or (2) generalized spikes/polyspikes with posterior emphasis. In ictal EEG, a well-localized unifocal rhythmic ictal discharge during occipital seizures is infrequent. A bioccipital field spread to the temporal regions is common. Frequency, severity, and response to treatment vary considerably from good to intractable and progressive mainly depending on underlying causes.

  11. Capitalismo, crisis y naturaleza: Un análisis del acaparamiento de tierras dentro y desde el Sur Global

    OpenAIRE

    Mora, Sol

    2016-01-01

    El acaparamiento de tierras (land grabbing) refiere al proceso de adquisiciones a gran escala de tierras agrícolas en otros estados, desatado en el contexto de la convergencia de crisis internacionales —alimentaria, energética, financiera y climática— de 2008. Este artículo analiza las razones que convirtieron al acaparamiento de tierras en un fenómeno global, irreductible a la lógica Norte-Sur. Adicionalmente, indaga sus implicaciones sobre la posición internacional y definici...

  12. Mass balance evolution of Martial Este Glacier, Tierra del Fuego (Argentina for the period 1960–2099

    Directory of Open Access Journals (Sweden)

    M. Buttstädt

    2009-12-01

    Full Text Available The Martial Este Glacier in southern Tierra del Fuego was studied in order to estimate the surface mass balance from 1960 until 2099. For this reason a degree-day model was calibrated. Air temperature and precipitation data obtained from 3 weather stations as well as glaciological measurements were applied. The model was driven using a vertical air temperature gradient of 0.69 K/100 m, a degree-day factor for snow of 4.7 mm w.e. K−1 day−1, a degree-day factor for ice of 9.4 mm w.e. K−1 day−1 and a precipitation gradient of 22%/100 m. For the purpose of surface mass balance reconstruction for the time period 1960 until 2006 a winter vertical air temperature gradient of 0.57 K/100 m and a summer vertical air temperature gradient of 0.71 K/100 m were added as well as a digital terrain model. The key finding is an almost continuous negative mass balance of −772 mm w.e. a−1 throughout this period. While the calculation of the mass balance for the period 1960–2006 is based on instrumental records, the mass balance for the years 2007 until 2099 was estimated based on the IPCC SRES A2-scenario. To accomplish this estimation, the dataset of the global climate model HadCM3 was statistically downscaled to fit local conditions at Martial Este Glacier. Subsequently, the downscaled air temperature and precipitation were applied to a volume-area scaling glacier change model. Findings reveal an enduring deglaciation resulting in a surface area reduction of nearly 93% until 2099. This implicates that the Martial Este Glacier might be melted off at the beginning of the 22nd century.

  13. Visión de la Concentración de la Tierra en América Latina

    NARCIS (Netherlands)

    C. Kay (Cristóbal)

    2012-01-01

    textabstractEn este breve artículo presento de manera muy general y esquemática algunos aspectos sobre la concentración de la tierra en América Latina. No pretendo hacer un análisis detallado y completo sobre la problemática de la tierra en la región. Pero espero poder resaltar algunos factores que

  14. Desplazamiento forzado y propiedad de la tierra en Antioquia, 1996-2004

    Directory of Open Access Journals (Sweden)

    Carlos Felipe Gaviria

    2007-06-01

    Full Text Available El desplazamiento forzoso es un fenómeno mundial que ha acompañado crisis políticas y sociales, relacionado, además, con el dominio del territorio por parte de los grupos inmersos en el conflicto. En Colombia, este fenómeno social se ha incrementado en los últimos años, junto con problemas agrarios, sociales y productivos. El objetivo de este artículo es analizar la relación existente entre el desplazamiento forzado y los procesos de concentración de la tierra en Antioquia entre 1996-2004. Se encuentra que existe una relación positiva entre propiedad de la tierra y desplazamiento forzado; en especial en Urabá y Oriente, subregiones antioqueñas con la producción agrícola más importante.

  15. Efecto de la impermeabilidad del Mucílago de Nopal en bloques de tierra comprimidos

    Directory of Open Access Journals (Sweden)

    Yolanda Guadalupe Aranda Jiménez

    2013-01-01

    Full Text Available La arquitectura de tierra1 es conocida desde hace siglos, sin embargo, actualmente es poco utilizada comparado con los sistemas constructivos comunes. Los bloques de tierra comprimido (BTC son elementos constructivos con un potencial elevado para ser utilizado en las construcciones de vivienda en México, principalmente por su similitud con los bloques tradicionales, siendo conveniente mejorar sus características a partir de un estabilizante. Se realizó el estudio de BTC estabilizados con cemento y una sustancia proveniente de las pencas maduras de nopal. Se encontró que al añadir mucílago de nopal se observa un incremento significativo de la resistencia a la compresión húmeda y seca, lo cual estar relacionado con una disminución de la porosidad; se ofrecen algunas relaciones del efecto del mucílago en el sólido analizado.

  16. Design of earth network in electric substations; Diseno de redes de tierra en subestaciones electricas

    Energy Technology Data Exchange (ETDEWEB)

    Raull-Martin, J. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    2000-09-01

    The purpose of this paper is to present a summarized version of the different types of construction of grounding systems, as web as their materials and formulas, which are necessary and useful for the design and building of a grounding network for medium to high voltage facilities. A description is also made of how to determine the electrical resistivity of subsoil layers with different physical characteristics. Several illustrative examples are also solved in the paper. [Spanish] El proposito de este articulo es presentar de manera resumida los diferentes tipos de construccion de los sistemas de tierra, asi como sus materiales y formulas, los cuales son necesarios y utiles para el diseno y edificacion de una red de tierra para instalaciones de mediana y alta tension. Se describe tambien la obtencion de las diferentes resistividades que presentan los terrenos con diversas caracteristicas fisicas. Asi mismo, se solucionan ejercicios ilustrativos a lo largo del articulo.

  17. Cultural Tourism In Fragile Institutional Contexts Project For Cultural Routes In Tierra Del Fuego

    Directory of Open Access Journals (Sweden)

    Eugenio Garcés Feliú

    2012-12-01

    Full Text Available The following paper presents a project of Cultural Routes designed for the Chilean Tierra del Fuego, linked to promoting tourism and boosting the economy, through the development of a specific high standard tourism offer, linked to its natural and cultural heritage, with the purpose of capturing the potential income generation for Chile. The project had as main goal to enhance the competitiveness of the tourism sector of special interests in Tierra del Fuego, a key sector of Southern Patagonia, through the dissemination and transfer of technologies and knowledge, acquired in over 10 years of research and projects, onto the territory and local agents. These Cultural Routes build an innovative offer, capable of structuring the diverse touristic resources and strengthening the basis for the development of a new stage of national and international tourism market, located on the southern extreme of Chile and America.

  18. Arquitectura de tierra -histórica y moderna- en Italia

    Directory of Open Access Journals (Sweden)

    Galdieri, Eugenio

    1986-02-01

    Full Text Available This work about the history of mud constructions in Italy -both of brick and formwork- gives an exposition of geographical zones where those are located, the kind of uses so as their possible historic origins, among which the author points the strong connections with Spanish adobe constructions, both in Cagliars (Aragonese influence and in Oristano (Castilian influence.El trabajo de carácter histórico sobre las construcciones con tierra en Italia, tanto de adobe como de tapial presenta una panorámica de las zonas geográficas en las que se encuentran enclavadas, así como el tipo de usos y posibles orígenes históricos, entre los que el autor señala los fuertes vínculos con las construcciones de tierra españolas, tanto en Cagliaria (influencia aragonesa como en Oristano (influencia castellana.

  19. Bryophyte diversity patterns in flooded and tierra firme forests in the Araracuara Region, Colombian Amazonia

    OpenAIRE

    Benavides, Juan C.; Idarraga, Alvaro; Alvarez, Esteban

    2004-01-01

    We investigated patterns of bryophyte species richness and composition in two forest types of Colombian Amazonia, non-flooded tierra firme forest and floodplain forest of the Caquetá River. A total of 109 bryophyte species were recorded from 14 0.2 ha plots. Bryophyte life forms and habitats were analyzed, including the canopy and epiphylls. Bryophyte species did not show significant differences between landscapes but mosses and liverworts were different and with opposite responses balancing ...

  20. The frontal lobes and inhibitory function

    International Nuclear Information System (INIS)

    Konishi, Seiki

    2011-01-01

    Neuropsychological studies using traditional tasks of inhibitory functions, such as the Wisconsin card sorting test (WCST) and the Go/No-Go Task have revealed that the frontal lobe is responsible for several types of inhibitory functions. However, the detailed psychological nature of the inhibitory functions and the precise location of their critical foci within the frontal lobe remain to be investigated. Functional magnetic resonance imaging provides spatial and temporal resolution that allowed us to illuminate at least 4 frontal regions involved in inhibitory functions: the dorsolateral, ventrolateral, and rostral parts of the frontal lobe and the presupplementary motor area (preSMA). The ventrolateral part of the frontal lobe in the right hemisphere was activated during response inhibition. The preSMA in the left hemisphere was activated during inhibition of proactive interference immediately after the dimension changes of the WCST. The rostral part of the frontal lobe in the left hemisphere was activated during inhibition long after the dimension changes. The dorsolateral part of the frontal lobe in the left hemisphere was activated at the dimension changes in the first time, but not in the second time. These findings provide clues to our understanding of functional differentiation of inhibitory functions and their localization in the frontal lobe. (author)

  1. La adecuación de tierras en el departamento de Antioquia.

    Directory of Open Access Journals (Sweden)

    Arango T. Julio César

    1999-06-01

    Full Text Available Los programas estatales de adecuación de tierras en Colombia comenzaron a partir de la década del 50, durante la cual se emprendió la construcción de infraestructuras básicas para el riego, el drenaje y el control de inundaciones. Las inversiones efectuadas por distintas entidades que en el país han tenido que ver con el Sector de la Adecuación de Tierras han sido cuantiosas y con ellas, se beneficiaron durante muchos años, los agricultores situados en distintas zonas planas de los departamentos del Tolima, Boyacá, Magdalena, Valle del Cauca entre otros. Antioquia durante este mismo tiempo, no se favoreció de esos recursos, por la carencia de políticas estatales en el Sector de la Adecuación de Tierras, solamente a partir de 1983, con el montaje por parte del HIMAT del Programa Nacional de Pequeña Irrigación, comienzan a solucionarse los problemas de manejo del agua para el riego de los cultivos en distintas veredas de Antioquia. Hoy se dispone de 29 distritos de riego en pequeña escala, los cuales corresponden a una superficie total de 3.759 ha, en las cuales, se benefician 1.510 familias campesinas.

  2. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G. [David Geffen School of Medicine at UCLA, Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, Los Angeles, CA (United States); Strange, Charlie [Medical University of South Carolina, Department of Pulmonary and Critical Care Medicine, Columbia, SC (United States); Tashkin, Donald P. [David Geffen School of Medicine at UCLA, Division of Pulmonary and Critical Care Medicine, Los Angeles, CA (United States)

    2012-07-15

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  3. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    International Nuclear Information System (INIS)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G.; Strange, Charlie; Tashkin, Donald P.

    2012-01-01

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  4. Características y Problemas de Tenencia de la Tierra en el Sector Agropecuario Colombiano

    Directory of Open Access Journals (Sweden)

    Tobón Restrepo Arturo

    1964-12-01

    Full Text Available El término “Tenencia” es bastante amplio, pues relaciona la posesión física de un bien sin importar la legitimidad en el dominio de él. En cuanto a la posesión nuestro Código Civil (3 estipula: "La posesión es la tenencia de una cosa determinada con ánimo de señor o dueño, sea que el dueño o el que se la da por tal tenga la cosa por sí misma, o por otra persona que la tenga en lugar y a nombre de él". Para nuestro fin concretemos únicamente en el aspecto de la tierra. El presente estudio se encauza hacia la economía agrícola y la administración rural, más que al aspecto jurídico de la tenencia de la tierra Es bien sabido que en el sistema económico cada factor de producción encierra numerosas especificaciones, además el uso de uno de ellos .implica la combinación en el uso de los demás. Es por ello que al hablar de solución a un problema no se debe decir que se llegue a salvar los obstáculos que impiden el desarrollo económico en el panorama nacional ya que la tenencia de la tierra es un rubro dentro de los muchos con que cuenta el factor tierra. Es claro, que no podría separarse por completo el concepto de tenencia de la tierra de las demás circunstancias de carácter económico en todos sus aspectos; pero las consideraciones que se harán en el transcurso del presente trabajo serán tomadas con cierta tendencia individualista hacia el tema en mención.

  5. TECNOLOGÍAS DE TRATAMIENTO PARA LA TIERRA FULLER CONTAMINADA CON ACEITE DIELÉCTRICO

    Directory of Open Access Journals (Sweden)

    Óscar Darío Beltrán Pérez

    Full Text Available Desde hace algunos años en Colombia se vienen implementando convenios y normas para el adecuado manejo y disposición final de los residuos peligrosos, debido a que la cantidad generada cada vez va en aumento y al impacto adverso que estos residuos presentan en el ser humano y el medio ambiente. La tierra Fuller es un material inorgánico adsorbente (mineral de aluminosilicatos principalmente, utilizado en la industria eléctrica para la regeneración del aceite dieléctrico, un derivado del petróleo empleado como aislante eléctrico y térmico en los transformadores de potencia. Después del proceso de regeneración del aceite, el contenido de hidrocarburos del tipo poliaromáticos (o los PAH por sus siglas en inglés que presenta la tierra Fuller la convierten en un residuo peligroso que requiere de un adecuado tratamiento, para que reduzca su contaminación y permita su reutilización o segura disposición final en un relleno sanitario. Por esto, en este artículo se revisan las tecnologías disponibles para el tratamiento de este tipo de residuo peligroso (tierra Fuller contaminada con aceite dieléctrico, dividiendo los tratamientos en dos corrientes, las tecnologías fisicoquímicas y las biológicas, explorando las alternativas más apropiadas y eficientes para su tratamiento. La escasa información acerca de los tratamientos existentes para la tierra Fuller contaminada con aceite dieléctrico han orientado la revisión en términos de las tecnologías implementadas en suelos contaminados con hidrocarburos siendo válida la analogía debido a las similares características físicas que presenta la tierra Fuller con respecto a un suelo de bajo contenido de carbono.

  6. Abundancia y Biomasa de Lombrices de Tierra en dos Ecosistemas Intervenidos del Bosque Trópica l Húmedo, Bluefields Las lombrices de tierra son el intestino de la tierra Gilbert White, 1789.

    Directory of Open Access Journals (Sweden)

    Gladys Luna

    2012-09-01

    Full Text Available Muchos estudios han demostrado que las lombrices de tierra (Anelidae son el componente más abundante de la macrofauna del suelo y desempeñan funciones ecológicas dentro de él.El objetivo fue evaluar la abundancia y biomasa de lombrices de tierra en dos hábitats del bosque tropical húmedo con diferentes usos de suelo en la ciudad de Bluefields, Región Autónoma Atlántico Sur (RAAS. En cada hábitat se seleccionaron dos micro-hábitats: uno con sombra y otro sin sombra y en cada uno se delimitaron tres subparcelas de 1pie2 cada una, y una profundidad de 10 cm, ubicadas al azar y a una distancia mínima de 15 m entre sí.Cada muestra de suelo se tamizó y se extrajeron, se midieron y se pesaron los individuos por subparcela. El número de lombrices registradas fue mayor en el hábitat de área reforestada que en el hábitat de bosque, pero ocurrió lo contrario con respecto al tamaño promedio de los individuos.La mayor disponibilidad de materia orgánica en el bosque puede explicar el mayor tamaño de los individuos en este sitio.En aquellos suelos que han sufrido alteraciones antrópicas, como en el campus universitario, las comunidades de lombrices han experimentado cambios extremos denotando así una mala salud; sin embargo, estas comunidades se están recuperando, especialmente en los microhabitats con sombra.

  7. La función económica social: un medio para el acceso y conservación de la tenencia de la tierra en Bolivia

    OpenAIRE

    Bejarano Torrejón, Hugo

    2017-01-01

    La tenencia de la tierra constituye un factor importante en la estructura productiva y de desarrollo de los Estados, por cuanto el equilibrio entre las fuerzas productivas denominadas tierra y hombre constituyen la base para un desarrollo armónico del área rural lo cual impacta también en el desarrollo del mismo Estado; así la tenencia de la tierra es la relación entre la cantidad de tierra existente en un determinado Estado y su población, mediando su ocupación o posesión. El principio ag...

  8. Alterations of the occipital lobe in schizophrenia.

    Science.gov (United States)

    Tohid, Hassaan; Faizan, Muhammad; Faizan, Uzma

    2015-07-01

    The relationship of the occipital lobe of the brain with schizophrenia is not commonly studied; however, this topic is considered an essential subject matter among clinicians and scientists. We conducted this systematic review to elaborate the relationship in depth. We found that most schizophrenic patients show normal occipital anatomy and physiology, a minority showed dwindled values, and some demonstrated augmented function and structure. The findings are laborious to incorporate within single disease models that present the involvement of the occipital lobe in schizophrenia. Schizophrenia progresses clinically in the mid-twenties and thirties and its prognosis is inadequate. Changes in the volume, the gray matter, and the white matter in the occipital lobe are quite evident; however, the mechanism behind this involvement is not yet fully understood. Therefore, we recommend further research to explore the occipital lobe functions and volumes across the different stages of schizophrenia.

  9. Pressure balance between lobe and plasma sheet

    International Nuclear Information System (INIS)

    Baumjohann, W.; Paschmann, G.; Luehr, H.

    1990-01-01

    Using eight months of AMPTE/IRM plasma and magnetic field data, the authors have done a statistical survey on the balance of total (thermal and magnetic) pressure in the Earth's plasma sheet and tail lobe. About 300,000 measurements obtained in the plasma sheet and the lobe were compared for different levels of magnetic activity as well as different distances from the Earth. The data show that lobe and plasma sheet pressure balance very well. Even in the worst case they do not deviate by more than half of the variance in the data itself. Approximately constant total pressure was also seen during a quiet time pass when IRM traversed nearly the whole magnetotail in the vertical direction, from the southern hemisphere lobe through the neutral sheet and into the northern plasma sheet boundary layer

  10. Microsurgical techniques in temporal lobe epilepsy.

    Science.gov (United States)

    Alonso Vanegas, Mario A; Lew, Sean M; Morino, Michiharu; Sarmento, Stenio A

    2017-04-01

    Temporal lobe resection is the most prevalent epilepsy surgery procedure. However, there is no consensus on the best surgical approach to treat temporal lobe epilepsy. Complication rates are low and efficacy is very high regarding seizures after such procedures. However, there is still ample controversy regarding the best surgical approach to warrant maximum seizure control with minimal functional deficits. We describe the most frequently used microsurgical techniques for removal of both the lateral and mesial temporal lobe structures in the treatment of medically intractable temporal lobe epilepsy (TLE) due to mesial temporal sclerosis (corticoamygdalohippocampectomy and selective amygdalohippocampectomy). The choice of surgical technique appears to remain a surgeon's preference for the near future. Meticulous surgical technique and thorough three-dimensional microsurgical knowledge are essentials for obtaining the best results. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  11. Deployment Instabilities of Lobed-Pumpkin Balloon

    Science.gov (United States)

    Nakashino, Kyoichi

    A lobed-pumpkin balloon, currently being developed in ISAS/JAXA as well as in NASA, is a promising vehicle for long duration scientific observations in the stratosphere. Recent ground and flight experiments, however, have revealed that the balloon has deployment instabilities under certain conditions. In order to overcome the instability problems, a next generation SPB called 'tawara' type balloon has been proposed, in which an additional cylindrical part is appended to the standard lobed-pumpkin balloon. The present study investigates the deployment stability of tawara type SPB in comparison to that of standard lobed-pumpkin SPB through eigenvalue analysis on the basis of finite element methods. Our numerical results show that tawara type SPB enjoys excellent deployment performance over the standard lobed-pumpkin SPBs.

  12. Alterations of the occipital lobe in schizophrenia

    Science.gov (United States)

    Tohid, Hassaan; Faizan, Muhammad; Faizan, Uzma

    2015-01-01

    The relationship of the occipital lobe of the brain with schizophrenia is not commonly studied; however, this topic is considered an essential subject matter among clinicians and scientists. We conducted this systematic review to elaborate the relationship in depth. We found that most schizophrenic patients show normal occipital anatomy and physiology, a minority showed dwindled values, and some demonstrated augmented function and structure. The findings are laborious to incorporate within single disease models that present the involvement of the occipital lobe in schizophrenia. Schizophrenia progresses clinically in the mid-twenties and thirties and its prognosis is inadequate. Changes in the volume, the gray matter, and the white matter in the occipital lobe are quite evident; however, the mechanism behind this involvement is not yet fully understood. Therefore, we recommend further research to explore the occipital lobe functions and volumes across the different stages of schizophrenia. PMID:26166588

  13. Ice Ages

    Indian Academy of Sciences (India)

    that the precession of the earth's orbit caused ice ages. The precession of the earth's orbit leads to changes in the time of the year at which ... than in the southern hemisphere. ..... small increase in ocean temperature implies a large increase in.

  14. Eulerian Method for Ice Crystal Icing

    NARCIS (Netherlands)

    Norde, Ellen; van der Weide, Edwin Theodorus Antonius; Hoeijmakers, Hendrik Willem Marie

    In this study, an ice accretion method aimed at ice crystal icing in turbofan engines is developed and demonstrated for glaciated as well as mixed-phase icing conditions. The particle trajectories are computed by an Eulerian trajectory method. The effects of heat transfer and phase change on the

  15. Sea ice - Multiyear cycles and white ice

    Science.gov (United States)

    Ledley, T. S.

    1985-01-01

    The multiyear thickness cycles represent one of the interesting features of the sea ice studies performed by Semtner (1976) and Washington et al. (1976) with simple thermodynamic models of sea ice. In the present article, a description is given of results which show that the insulating effect of snow on the surface of the sea ice is important in producing these multiyear cycles given the physics included in the model. However, when the formation of white ice is included, the cycles almost disappear. White ice is the ice which forms at the snow-ice interface when the snow layer becomes thick enough to depress the ice below the water level. Water infiltrates the snow by coming through the ice at leads and generally freezes there, forming white ice.

  16. Epidemiología de las lesiones por mordedura de perro en Tierra del Fuego, Argentina Epidemiology of dog bite lesions in Tierra del Fuego, Argentina

    Directory of Open Access Journals (Sweden)

    Fabián Zanini

    2008-02-01

    Full Text Available La convivencia del hombre y el perro ha resultado en beneficios mutuos durante miles de años, si bien en el último tiempo han surgido una serie de inconvenientes donde las lesiones por mordeduras ocupan un lugar destacado. El objetivo del presente trabajo fue describir las características epidemiológicas de las lesiones por mordedura de perro ocurridas a lo largo de un año en Tierra del Fuego. Se realizó un estudio observacional descriptivo, transversal, de los pacientes que ingresaron con lesiones por mordedura de perro al Servicio de Guardia Clínica y Pediátrica de los Hospitales y Centros de Salud desde el 1/3/05 hasta el 1/3/06. Se confeccionaron 382 planillas. El 49.5% fueron niños resultando más afectado el grupo de 5-9 años (44.4%; IC95% 37.2-51.8. En adultos correspondió al grupo de 15-24 años (29.5%; IC95% 23.2-36.5. Se registraron más lesiones en varones (57.6% que en mujeres (42.4% (x² = 8.6, p= 0.003. En los meses primavera y verano se registró el 56.5% de las lesiones, en la vía pública el 72.8% de ellas. Los perros de tamaño grande causaron el 49.7% (IC95% 44.6-54.9 de las lesiones. El 89.8% de los ataques fueron causados por perros ajenos. El 55.8% (IC95% 50.6-60.8 se registró en miembros inferiores y el 11% (IC95% 8.1-14.7 en cabeza y cuello. Los datos obtenidos demuestran que en Tierra del Fuego las lesiones por mordedura de perro afectan en forma permanente la salud e impactan en la calidad de vida de la población.The coexistence between man and dog has resulted in mutual benefits during thousands of years, nevertheless some problems have recently arisen where bite injuries have an important role. The aim of this work was to describe the epidemiological characteristics of dog bite lesions which occurred during a year in Tierra del Fuego. A descriptive observational, transversal study of patients who were admitted with dog bite injuries to clinic and pediatric emergency services of hospitals and health

  17. MRI findings of temporal lobe ganglioglioma

    International Nuclear Information System (INIS)

    Lee, Myung Jun; Lee, Ho Kyu; Lee, Jung Kyo; Choi, Choong Gon; Suh, Dae Chul

    1999-01-01

    Ganglioglioma is a rare primary brain tumor usually found in the temporal lobe. The purpose of this study is to describe the characteristic MR findings of temporal lobe ganglioglioma. Over a seven-year period, ten patients with cerebral ganglioglioma were evaluated at our institution. Seven cases of temporal lobe ganglioma were found ; six of these involved men, and one, a woman ; their mean age was 29.6 years. In three patients, Gd-DTPA-enhanced T1-weighted images were also obtained. We retrospectively analysed the MRI findings with respect to location, size, cortical involvement, margin, cystic change, degree of enhancement, MR signal intensity, calcification and peritumoral change. In five cases, tumors were located within the temporal lobe. In one, a tumor extended from the temporal lobe to the thalamus, and in one from the temporal lobe to the thalamus and cerebral peduncle. All temporal gangliogliomas measured 1.6-3.8cm in their greatest diameter (mean diameter, 2.7cm). In all cases, the cortices were involved with the maintenance of gyriform. The tumor margin was ill defined in five cases and well defined in two. Tumors showed multiple small cystic changes in four cases, a large cyst in two, and a solid nodule in one. In three cases in which contrast media was administered, no lesions were enhanced. On T1-weighted images, iso-signal intensities were seen in five cases and high signal intensities in two. On T2-weighted images, the corresponding figures were five and two. On MRI, tumor calcification and calvarial erosion were each detected in two cases. In patients with temporal lobe epilepsy in whom cortical solid or cystic and poorly enhanced lesions were seen on brain MRI, and in whom associated findings such as calcification and or adjacent bony erosion were noted, ganglioglioma must be considered

  18. Microsurgical anatomy of the central lobe.

    Science.gov (United States)

    Frigeri, Thomas; Paglioli, Eliseu; de Oliveira, Evandro; Rhoton, Albert L

    2015-03-01

    The central lobe consists of the pre- and postcentral gyri on the lateral surface and the paracentral lobule on the medial surface and corresponds to the sensorimotor cortex. The objective of the present study was to define the neural features, craniometric relationships, arterial supply, and venous drainage of the central lobe. Cadaveric hemispheres dissected using microsurgical techniques provided the material for this study. The coronal suture is closer to the precentral gyrus and central sulcus at its lower rather than at its upper end, but they are closest at a point near where the superior temporal line crosses the coronal suture. The arterial supply of the lower two-thirds of the lateral surface of the central lobe was from the central, precentral, and anterior parietal branches that arose predominantly from the superior trunk of the middle cerebral artery. The medial surface and the superior third of the lateral surface were supplied by the posterior interior frontal, paracentral, and superior parietal branches of the pericallosal and callosomarginal arteries. The venous drainage of the superior two-thirds of the lateral surface and the central lobe on the medial surface was predominantly through the superior sagittal sinus, and the inferior third of the lateral surface was predominantly through the superficial sylvian veins to the sphenoparietal sinus or the vein of Labbé to the transverse sinus. The pre- and postcentral gyri and paracentral lobule have a morphological and functional anatomy that differentiates them from the remainder of their respective lobes and are considered by many as a single lobe. An understanding of the anatomical relationships of the central lobe can be useful in preoperative planning and in establishing reliable intraoperative landmarks.

  19. Habitar en Tierras Secas: La Tierra Cruda como vehículo de habitabilidad en el territorio no irrigado del norte de la Provincia de Mendoza, Argentina

    Directory of Open Access Journals (Sweden)

    Virginia Miranda Gassull

    2015-12-01

    Full Text Available El territorio no irrigado del norte de la provincia de Mendoza es un vasto espacio sin acceso al bien hídrico, donde habita dispersa una población campesina de identidad originaria Huarpe. Habitar en este territorio ha sido desde hace siglos un desafío tanto al clima/ambiente como a condiciones sociopolíticas. Por lo tanto, el hábitat en tierras secas presenta particulares características respecto a su forma de gestión (autónoma, a su adaptación al ambiente y al uso de la técnica constructiva con tierra cruda: adobe. El objetivo a desarrollar aquí se sustenta en el uso actual del adobe, concebido como un vehículo que facilita la autoconstrucción y autoproducción de soluciones habitacionales en poblaciones desposeídas, ajustando su vivienda a las implicancias de un territorio árido y a un largo proceso de vulnerabilidad de derechos. Este artículo aproxima los primeros resultados de los relevamientos realizados sobre la técnica constructiva del adobe (a través de técnicas cuantitativas: encuesta y muestras in situ y las características propias del hábitat social de la población originaria Huarpe, a partir de la técnica de la observación participante.

  20. Forecasting Turbine Icing Events

    DEFF Research Database (Denmark)

    Davis, Neil; Hahmann, Andrea N.; Clausen, Niels-Erik

    2012-01-01

    In this study, we present a method for forecasting icing events. The method is validated at two European wind farms in with known icing events. The icing model used was developed using current ice accretion methods, and newly developed ablation algorithms. The model is driven by inputs from the WRF...... mesoscale model, allowing for both climatological estimates of icing and short term icing forecasts. The current model was able to detect periods of icing reasonably well at the warmer site. However at the cold climate site, the model was not able to remove ice quickly enough leading to large ice...

  1. Mapa de usos potenciales de la tierra de Galicia. Una perspectiva arqueológica

    Directory of Open Access Journals (Sweden)

    Currás Refojos, Brais X.

    2014-06-01

    Full Text Available A digital version of the map of potential land use of Galicia is here presented, adapted to a reclassification of three types of potential land use, established using historical criteria. An analytical procedure is developed to select the land-types and the system used for their digitalisation. In the final part the map is used to critically revise the possibilities of using this record for territorial characterisation in archaeological research.La cartografía de usos potenciales de la tierra es una herramienta de gran utilidad en el estudio de las formas de poblamiento y su relación con la explotación de los recursos agrícolas desde el enfoque de la arqueología del paisaje. La digitalización de esta información permite su aplicación sistemática en el análisis del territorio mediante SIG. En este trabajo se presenta el Mapa de usos potenciales de la tierra de Galicia, reclasificado en tres tipos establecidos en función de criterios históricos. Se muestra el procedimiento analítico desarrollado para la selección y clasificación de los tipos de tierra y su sistema de digitalización. Se examina la validez de esta fuente para la investigación arqueológica de las formas agrícolas en la antigu.edad desde el punto de vista del análisis del territorio y se ofrece una visión crítica sobre sus ventajas y limitaciones.

  2. The occipital lobe convexity sulci and gyri.

    Science.gov (United States)

    Alves, Raphael V; Ribas, Guilherme C; Párraga, Richard G; de Oliveira, Evandro

    2012-05-01

    The anatomy of the occipital lobe convexity is so intricate and variable that its precise description is not found in the classic anatomy textbooks, and the occipital sulci and gyri are described with different nomenclatures according to different authors. The aim of this study was to investigate and describe the anatomy of the occipital lobe convexity and clarify its nomenclature. The configurations of sulci and gyri on the lateral surface of the occipital lobe of 20 cerebral hemispheres were examined in order to identify the most characteristic and consistent patterns. The most characteristic and consistent occipital sulci identified in this study were the intraoccipital, transverse occipital, and lateral occipital sulci. The morphology of the transverse occipital sulcus and the intraoccipital sulcus connection was identified as the most important aspect to define the gyral pattern of the occipital lobe convexity. Knowledge of the main features of the occipital sulci and gyri permits the recognition of a basic configuration of the occipital lobe and the identification of its sulcal and gyral variations.

  3. MRI in patients with temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Kodama, Kazuhiro

    1992-01-01

    The present study investigated magnetic resonance imaging (MRI) features in temporal lobe epilepsy and correlated them with clinical variables, such as age, illness duration, past history, and the frequency of seizure. Cerebral MRI was performed in 45 patients with temporal lobe epilepsy of unknown etiology, using a 0.5 T and/or a 1.5 T MRI systems. The temporal lobe was seen as high signal intensity on T2-weighted images and/or proton density-weighted images in 6 patients, although it was missed on CT and T1-weighted images. The high intensity area seemed to reflect sclerosis of the temporal lobe. This finding was significantly associated with partial seizure. Of these patients, 3 had a history of febrile convulsions. Ten patients had slight dilatation of the inferior horn of the lateral ventricle. They were significantly old at the time of onset and examination, as compared with those without dilatation. Furthermore, 6 patients with unilateral dilatation were significantly younger than the other 4 with bilateral dilatation. Nine patients had small multiple high signal areas in white matter, mainly in the parietal lobe, which suggested vascular origin. These patients were significantly old at the time of onset and examination, as compared with those having no such findings. In depicting high signal intensity areas, a 1.5 T MRI system was not always superior to a 0.5 T MRI system. Proton density-weighted images were better than T2-weighted images in some patients. (N.K.)

  4. [Tierra del Fuego: the scientific-political construction of exclusion and counter-image of the ideal city dweller].

    Science.gov (United States)

    Nacach, Gabriela

    2012-01-01

    Due to its late incorporation into the national State, the social, economic and political setting of the Argentine province Tierra del Fuego differed from that of the rest of the national territory. In the construction of dependent otherness, objectifications and representations were imposed by state-related and non-state-related institutions, among other agencies. In this context, the Salesian mission of La Candelaria and Ushuaia's Jail for recidivists stand out as spaces in which biopolitics was concretised. The native population and criminals in Tierra del Fuego were those to be subjugated. The thesis of the extinction of the Indian and the simultaneous exaltation of the criminal as the subject of progress identified the scientific and political mechanisms by which the exclusion of certain social groups (Tierra del Fuego's indigenous population) and the inclusion of others (criminals) were regulated.

  5. Las normativas de construcción con tierra en el mundo

    Directory of Open Access Journals (Sweden)

    Cid, J.

    2011-09-01

    Full Text Available For centuries, earth has been used as a construction material. Nevertheless, the normative in this matter is very scattered, and in the most developed countries, carrying out a construction with this material implies a variety of technical and legal problems. This article analyzes, in an international level, the normative panorama about constructions with earth, analyzing fifty five standards and regulations of countries all around the five continents; these represent the state of art that normalizes the earth as a construction material. It is a study indexed on the actual procedures and regulations developed by the national organisms of normalization or correspondent authorities. The standards and the organisms that produce them appear, analyzing the structure and the content of each one. We have studied and analyzed the most relevant aspects, such as stabilization, soil selections, the requisites of the products and the existent test, comparing the diverse normative. The knowledge from this study could be very useful for the development of future standards and as a reference for architects and engineers that work with earth.

    La tierra ha sido utilizada como material de construcción desde hace siglos. No obstante, la normativa al respecto está muy dispersa, y en la mayoría de países desarrollados surgen numerosos problemas técnicos y legales para llevar a cabo una construcción con este material. Este artículo estudia el panorama normativo para las construcciones con tierra cruda a nivel internacional, analizando cincuenta y cinco normas y reglamentos de países repartidos por los cinco continentes, que representan el estado del arte de la normalización de la tierra cruda como material de construcción. Es un estudio referenciado sobre las normas y reglamentos vigentes desarrollados por los organismos nacionales de normalización o autoridades correspondientes. Se presentan las normativas y los organismos que las emiten

  6. Modelo de levantamiento de informacion fisica catastral para el Instituto Nacional de Tierras, oficina regional Trujillo

    OpenAIRE

    Castellanos, Víctor

    2011-01-01

    Se identificó la metodología utilizada para el catastro físico de los Asentamientos Campesinos del Estado Trujillo, durante la vigencia del Instituto Agrario Nacional, y la existente actualmente con el Instituto Nacional de Tierras, Ofi cina Regional Trujillo. La evaluación de esta información determinó la propuesta de un modelo de levantamiento con fi nes de densifi cación de redes geodésicas utilizando tecnología satelital GPS, que facilite la actualización catastral de los pred...

  7. Infectious Causes of Right Middle Lobe Syndrome.

    Science.gov (United States)

    Rashid, Aatif; Nanjappa, Sowmya; Greene, John N

    2017-01-01

    Right middle lobe (RML) syndrome is defined as recurrent or chronic obstruction or infection of the middle lobe of the right lung. Nonobstructive causes of middle lobe syndrome include inflammatory processes and defects in the bronchial anatomy and collateral ventilation. We report on 2 case patients with RML syndrome, one due to infection with Mycobacterium avium complex followed by M asiaticum infection and the other due to allergic bronchopulmonary aspergillosis. A history of atopy, asthma, or chronic obstructive pulmonary disease has been reported in up to one-half of those with RML. The diagnosis can be made by plain radiography, computed tomography, and bronchoscopy. Medical treatment consists of bronchodilators, mucolytics, and antimicrobials. Patients whose disease is unresponsive to treatment and those with obstructive RML syndrome can be offered surgical treatment.

  8. Medical image of the week: azygous lobe

    Directory of Open Access Journals (Sweden)

    Bhupinder Natt

    2013-12-01

    Full Text Available No abstract available. Article truncated at 150 words. A 59 year old man underwent chest radiography for evaluation of fever and cough. Imaging showed an accessory azygous lobe. An azygos lobe is found in 1% of anatomic specimens and forms when the right posterior cardinal vein, one of the precursors of the azygos vein, fails to migrate over the apex of the lung (1. Instead, the vein penetrates the lung carrying along pleural layers that entrap a portion of the right upper lobe. The vein appears to run within the lung, but is actually surrounded by both parietal and visceral pleura. The azygos fissure therefore consists of four layers of pleura, two parietal layers and two visceral layers, which wrap around the vein giving the appearance of a tadpole. Apart from an interesting incidental radiological finding, it is of limited clinical importance except that its presence should be recognized during thoracoscopic procedures. This patient was found to have …

  9. Lung lobe collapse: pathophysiology and radiologic significance

    International Nuclear Information System (INIS)

    Lord, P.F.; Gomez, J.A.

    1985-01-01

    The radiographic changes caused by collapse of lung lobes in pulmonary disease, pneumothorax, and pleural effusion depend on the lobar recoiling force and local pleural pressure. Differences in the tendency of normal lung lobes or regions to collapse depend on the relative surface-to-volume ratio, determined by shape and size of the region or lobe. This ratio affects the physiologic parameters of pulmonary interdependence, compliance, and collateral air flow. Pulmonary surfactant increases compliance, particularly at low volumes, maintains alveolar stability, and assists in maintaining capillary patency and preventing pulmonary edema. Its loss due to lung injury increases collapsing forces. In the presence of pneumothorax or pleural effusion, diseases that cause lobar collapse produce localized air or fluid entrapment that is a diagnostic sign of the presence of the underlying pulmonary disease

  10. Great Lakes Ice Charts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Charts show ice extent and concentration three times weekly during the ice season, for all lakes except Ontario, from the 1973/74 ice season through the 2001/2002...

  11. Inverted Lobes Have Satisfactory Functions Compared With Noninverted Lobes in Lung Transplantation.

    Science.gov (United States)

    Kayawake, Hidenao; Chen-Yoshikawa, Toyofumi F; Motoyama, Hideki; Hamaji, Masatsugu; Hijiya, Kyoko; Aoyama, Akihiro; Goda, Yasufumi; Oda, Hiromi; Ueda, Satoshi; Date, Hiroshi

    2018-04-01

    To overcome the problem of small-for-size grafts in standard living-donor lobar lung transplantation (LDLLT), we developed inverted LDLLT, in which a right lower lobe from 1 donor is implanted as a right graft and another right lower lobe from another donor is implanted as a left graft. We retrospectively analyzed the functions of inverted grafts vs noninverted grafts. Between 2008 and 2015, 64 LDLLTs were performed. Included were 35 LDLLTs whose recipients were adults and monitored for more than 6 months without developing chronic lung allograft dysfunction. Among them, 65 implanted lobes were eligible for this analysis. There were 31 right lower lobes implanted as right grafts (right-to-right group), 7 right lower lobes as inverted left grafts (right-to-left group), and 27 left lower lobes as left grafts (left-to-left group). We evaluated the graft forced vital capacity (G-FVC) and graft volume of the 65 lobes before and 6 months after LDLLT and compared them among the three groups. Preoperatively, G-FVC in the right-to-left group (1,050 mL) was comparable to that in the right-to-right group (1,177 mL) and better than that in the left-to-left group (791 mL, p satisfactory compared with those of noninverted grafts. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Temporal lobe sclerosis associated with hippocampal sclerosis in temporal lobe epilepsy: neuropathological features.

    Science.gov (United States)

    Thom, Maria; Eriksson, Sofia; Martinian, Lillian; Caboclo, Luis O; McEvoy, Andrew W; Duncan, John S; Sisodiya, Sanjay M

    2009-08-01

    Widespread changes involving neocortical and mesial temporal lobe structures can be present in patients with temporal lobe epilepsy and hippocampal sclerosis. The incidence, pathology, and clinical significance of neocortical temporal lobe sclerosis (TLS) are not well characterized. We identified TLS in 30 of 272 surgically treated cases of hippocampal sclerosis. Temporal lobe sclerosis was defined by variable reduction of neurons from cortical layers II/III and laminar gliosis; it was typically accompanied by additional architectural abnormalities of layer II, that is, abnormal neuronal orientation and aggregation. Quantitative analysis including tessellation methods for the distribution of layer II neurons supported these observations. In 40% of cases, there was a gradient of TLS with more severe involvement toward the temporal pole, possibly signifying involvement of hippocampal projection pathways. There was a history of a febrile seizure as an initial precipitating injury in 73% of patients with TLS compared with 36% without TLS; no other clinical differences between TLS and non-TLS cases were identified. Temporal lobe sclerosis was not evident preoperatively by neuroimaging. No obvious effect of TLS on seizure outcome was noted after temporal lobe resection; 73% became seizure-free at 2-year follow-up. In conclusion, approximately 11% of surgically treated hippocampal sclerosis is accompanied by TLS. Temporal lobe sclerosis is likely an acquired process with accompanying reorganizational dysplasia and an extension of mesial temporal sclerosis rather than a separate pathological entity.

  13. La industria textil en Tierra de Campos afines de la Edad Media

    Directory of Open Access Journals (Sweden)

    Hipólito Rafael OLIVA HERRER

    2009-12-01

    Full Text Available RESUMEN: El presente articulo trata de analizar el desarrollo de la industria textil rural en la región de Tierra de Campos, en torno al tradicional centro de producción textil de Palencia, a fines del XV y comienzos del XVI. La producción en el entorno rural conoció un amplio desarrollo basado en la producción de paños de calidad media-baja destinados al consumo interno, y dio lugar a formas organizativas complejas que se constituyeron en una alternativa frente al sistema gremial imperante en la urbe palentina, implicando intereses de un amplio espectro de grupos sociales.ABSTRACT: The present article aims to analyze the spreading of the rural textile industry in the region of Tierra de Campos in the late fifteenth and the early sixteenth centuries, around the traditional productive centre of Palencia. Here rural clothing experienced an important development based on the production of low and medium quality cloth under a putting-out system directed to interregional trade. The interests around rural industry involved a wide range of social groups, giving rise to complex organization forms and arising as an alternative to the traditional gudd stmcture.

  14. Ecohydrological features of some contrasting mires in Tierra del Fuego, Argentina

    Directory of Open Access Journals (Sweden)

    A. Grootjans

    2010-01-01

    Full Text Available In November 2005, Tierra del Fuego (Argentina hosted the biennial conference and field excursion of the International Mire Conservation Group (IMCG. The group considered the vegetation, hydrology, peat stratigraphy and possible management options for about 20 mires which were visited during a seven-day excursion. We report here some field observations and measurements of electrical conductivity (EC25 in five mires which have been selected to encompass the most important ecohydrological features of the mires of Tierra del Fuego. Existing and new data on landscape topography and vegetation were combined in three-dimensional drawings. These drawings are actually conceptual models which could underpin further ecohydrological research, and proved to be very useful as a basis for discussions amongst conference participants about possible ecohydrological relationships. The mires that were studied developed under a wide range of climatic conditions and included fens and bogs. The bogs typically developed from lakes or fens and most are now dominated by Sphagnum magellanicum. This species forms large hummocks, and can invade weakly-buffered fens. Most of the mires were well preserved, but effects of human impact - such as road building and peat extraction - were also noticeable.

  15. State of knowledge of the Corallinales (Rhodophyta of Tierra del Fuego and the Antarctic Peninsula

    Directory of Open Access Journals (Sweden)

    María Laura Mendoza

    1999-12-01

    Full Text Available Corallinales (Rhodophyta in Tierra del Fuego are abundant, with 9 genera, 17 species and 1 subspecies. Pseudolithophyllum with 1 species (P. fueguianum, which represents 35.8% of the coralline algae, is dominant. The genera Parahydrolithon with 4 species (P. consociatum, P. discoideum, P. falklandicum, P. subantarcticum and 20%, Lithothamnion with 3 species (Lt. heterocladum, Lt. rugosum, Lt. granuliferum and 17.5%, and Synarthrophyton with 3 species (S. neglectum, S. patena, S. schmitzii and 12% share are abundant. Clathromorphum with 4 species (Cl. annulatum, Cl. lemoineanum, Cl. obtectulum, Cl. Variabile and a share of 5.8%, and Mesophyllum with 1 species (M. fueguianum and a share of 4.9% are frequent. The remaining three genera, Bossiella with 1 subspecies (B. orbigniana ssp. orbigniana, Corallina with 2 species (C. elongata, C. officinalis (1.1%, and Titanoderna with 1 species (T. conspectum (1% are scarce. C. officinalis is a cosmopolitan, and the other geniculate corallines are found in both hemispheres, whereas the crustose coralline occur only in the southern hemisphere. The characteristic vertical distribution of the species in the intertidal and subtidal zone of Tierra del Fuego is given. The Corallinales in the Antarctic Region are poorly known and need further investigation.

  16. Controlling factors of turf-banked solifluction lobe evolution in the Turtmann glacier forefield (Switzerland)

    Science.gov (United States)

    Draebing, Daniel; Eichel, Jana

    2016-04-01

    Soil structure and moisture, thermal conditions and vegetation control solifluction movement, however, the spatial distribution of controlling factors and resultant spatial variability of movement are poorly understood. We use a (1) geomorphological and vegetation mapping of solifluction lobe properties, (2) temperature loggers to quantify thermal conditions, (3) 2D Electrical Resistivity Tomography (ERT), Puerkhauer drilling and TDR measurements to evaluate material properties as well as (4) 3D Time-Lapse ERT to quantify spatial variability of material properties. Our results are used to (5) evaluate the influence of potential controlling factors on solifluction movement. Investigations took place on three turf-banked lobes (TBL) located at proximal and distal slopes of Little Ice Age and 1920s lateral moraines in the Turtmann glacier forefield, Swiss Alps. (1) Vegetation is spatially differentiated at TBLs. The treads are mostly covered by the ecosystem engineer Dryas octopetala, while other dwarf shrubs, shrubs and pioneer species were found at the high lobe risers (0.8-1.8 m). In contrast, less vegetated ridge-like features at the upper part of the treads are colonized by frost-tolerant species. Large blocks are located at the lobe fronts, probably impeding the lobe movement. (2) Temperature loggers show a lack of ground cooling due to snow isolation at the vegetated lower tread between 2014 and 2015. Thus, significant ground cooling in winter is reduced to the wind-exposed upper parts (ridges). (3) TBL material consists of sandy silt, thus, lobe material is much finer than subjacent moraine till and indicates former colluviation. As a consequence, 2D ERT demonstrates low-resistant areas until depths equal to riser height, thus, the finer TBL body is higher saturated than the coarser surrounding parent slope and more susceptible to gelifluction. On the contrary, risers show high resistivities indicating dry conditions which are supported by TDR results

  17. Gene expression profile in temporal lobe epilepsy

    NARCIS (Netherlands)

    Aronica, Eleonora; Gorter, Jan A.

    2007-01-01

    Epilepsy is one of the most common neurological disorders. Temporal lobe epilepsy (TLE) represents the most frequent epilepsy syndrome in adult patients with resistance to pharmacological treatment. In TLE, the origin of seizure activity typically involves the hippocampal formation, which displays

  18. Gene expression profile in temporal lobe epilepsy.

    NARCIS (Netherlands)

    Aronica, E.M.A.; Gorter, J.A.

    2007-01-01

    Epilepsy is one of the most common neurological disorders. Temporal lobe epilepsy (TLE) represents the most frequent epilepsy syndrome in adult patients with resistance to pharmacological treatment. In TLE, the origin of seizure activity typically involves the hippocampal formation, which displays

  19. Formation of Bipolar Lobes by Jets

    Science.gov (United States)

    Soker, Noam

    2002-04-01

    I conduct an analytical study of the interaction of jets, or a collimated fast wind (CFW), with a previously blown asymptotic giant branch (AGB) slow wind. Such jets (or CFWs) are supposedly formed when a compact companion, a main-sequence star, or a white dwarf accretes mass from the AGB star, forms an accretion disk, and blows two jets. This type of flow, which I think shapes bipolar planetary nebulae (PNs), requires three-dimensional gasdynamical simulations, which are limited in the parameter space they can cover. By imposing several simplifying assumptions, I derive simple expressions which reproduce some basic properties of lobes in bipolar PNs and which can be used to guide future numerical simulations. I quantitatively apply the results to two proto-PNs. I show that the jet interaction with the slow wind can form lobes which are narrow close to, and far away from, the central binary system, and which are wider somewhere in between. Jets that are recollimated and have constant cross section can form cylindrical lobes with constant diameter, as observed in several bipolar PNs. Close to their source, jets blown by main-sequence companions are radiative; only further out they become adiabatic, i.e., they form high-temperature, low-density bubbles that inflate the lobes.

  20. Centrifugal acceleration in the magnetotail lobes

    Directory of Open Access Journals (Sweden)

    H. Nilsson

    2010-02-01

    Full Text Available Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outside a few RE. The measurement technique yields both density and bulk velocity, which can be combined with magnetic field measurements to estimate the centrifugal acceleration experienced by these particles. We present a quantitative estimate of the centrifugal acceleration, and the velocity change with distance which we would expect due to centrifugal acceleration. It is found that the centrifugal acceleration is on average outward with an average value of about of 5 m s−2. This is small, but acting during long transport times and over long distances the cumulative effect is significant, while still consistent with the relatively low velocities estimated using the combination of EFW and EDI data. The centrifugal acceleration should accelerate any oxygen ions in the lobes to energies observable by particle spectrometers. The data set also put constraints on the effectiveness of any other acceleration mechanisms acting in the lobes, where the total velocity increase between 5 and 19 RE geocentric distance is less than 5 km s−1.

  1. Radiologic evaluation of right middle lobe collapse

    International Nuclear Information System (INIS)

    Kwun, Dae Young; Kim, Jong Deok; Kim, Jong Chul

    1989-01-01

    There are many pathogenetic factors for collapse of right middle lobe; profuse peribronchial clustering of lymph nodes about the right middle lobe bronchus, poor drainage of the bronchus because of its acute angle of take-off from the intermediate bronchus, and the isolation of this small lobe from the right upper and lower lobes, and thus from the aerating effects of collateral ventilation. Retrospectively we reviewed 36 cases of right of right middle lobe collapse of which causes were confirmed by histopathologic or bronchographic findings during the recent 6 years from March 1983 to February 1988 at Inje College Pusan Paik Hospital, and obtained the following results: 1. Male to female ratio was 1:1:4,and peak incidence (64%) was in the fifth and sixth decades with the mean age of 51.1 years. 2. Bronchiectasis was the most common cause (30.6%), and the others were chronic bronchitis (25.0%), pulmonary tuberculosis (19.4%), lung cancer (16.7%), and non-specific inflammatory disease (8.3%). This suggests benign disease is 5 times more common cause of right middle lobe collapse than lung cancer. 3. Among the plain chest radiolograph findings, obliteration of right cardiac border and triangular radiopaque density were the most frequent findings(77.8% in each) and the next was downward and anterior displacement of minor and major fissures (55.6%) 4. Bronchography was done in 11 cases; bronchiectasis was found in 8 cases and chronic bronchitis in 3 cases. Right middle lobe bronchus was obstructed in 2 cases of chronic bronchitis. 5. Chest CT scan was performed in 4 cases of lung cancer, 2 of non-specific inflammatory disease, and 1 of pulmonary tuberculosis: all of lung cancer revealed hilar mass, budged or lobulated fissures, in homogenous density, and mediastinal lymph node enlargement, and all benign disease showed homogenous density and flat to concave fissures. Right middle lobar bronchus narrowing was seen in 5 cases and its obstruction in 2 cases

  2. Frontal lobe atrophy in motor neuron diseases.

    Science.gov (United States)

    Kiernan, J A; Hudson, A J

    1994-08-01

    Neuronal degeneration in the precentral gyrus alone cannot account for the occurrence of spastic paresis in motor neuron diseases. To look for more extensive cortical atrophy we measured MRIs of the upper parts of the frontal and parietal lobes in 11 sporadic cases of classical amyotrophic lateral sclerosis (ALS), eight patients with primary lateral sclerosis (PLS) and an age- and sex-matched group of 49 neurologically normal people. None of the patients had overt dementia or other mental diseases. In PLS there is progressive spastic paresis but in contrast to ALS there is no lower motor neuron degeneration. The surface area of the precentral gyri and the amount of underlying white matter in PLS were consistently approximately 75% of the normal size. By contrast, there was some shrinkage of the precentral gyri in some of the ALS patients but the mean measurements for the group did not differ significantly from the controls. Anterior to the precentral sulci, the cortical surface area in PLS was approximately 85% of that of the controls, with correspondingly reduced white matter. In ALS the cortical surface areas of the anterior frontal lobes did not differ from those of the controls, but the amount of underlying white matter was reduced almost as much in ALS as it was in PLS. The measured changes in the frontal lobes suggest that in PLS there is simultaneous atrophy of the primary, premotor and supplementary motor areas of the cortex, with consequent degeneration of corticospinal and corticoreticular axons descending through the underlying white matter. These changes could account for the progressive upper motor neuron syndrome. In ALS, with no significant frontal cortical atrophy, the shrinkage of the white matter may be due to degeneration of axons projecting to the frontal cortex from elsewhere. Deprivation of afferents could explain the diminution of motor functions of the frontal lobes in ALS and also the changes in word fluency, judgement and attention that

  3. Semantic memory is impaired in patients with unilateral anterior temporal lobe resection for temporal lobe epilepsy.

    Science.gov (United States)

    Lambon Ralph, Matthew A; Ehsan, Sheeba; Baker, Gus A; Rogers, Timothy T

    2012-01-01

    Contemporary clinical and basic neuroscience studies have increasingly implicated the anterior temporal lobe regions, bilaterally, in the formation of coherent concepts. Mounting convergent evidence for the importance of the anterior temporal lobe in semantic memory is found in patients with bilateral anterior temporal lobe damage (e.g. semantic dementia), functional neuroimaging and repetitive transcranial magnetic stimulation studies. If this proposal is correct, then one might expect patients with anterior temporal lobe resection for long-standing temporal lobe epilepsy to be semantically impaired. Such patients, however, do not present clinically with striking comprehension deficits but with amnesia and variable anomia, leading some to conclude that semantic memory is intact in resection for temporal lobe epilepsy and thus casting doubt over the conclusions drawn from semantic dementia and linked basic neuroscience studies. Whilst there is a considerable neuropsychological literature on temporal lobe epilepsy, few studies have probed semantic memory directly, with mixed results, and none have undertaken the same type of systematic investigation of semantic processing that has been conducted with other patient groups. In this study, therefore, we investigated the semantic performance of 20 patients with resection for chronic temporal lobe epilepsy with a full battery of semantic assessments, including more sensitive measures of semantic processing. The results provide a bridge between the current clinical observations about resection for temporal lobe epilepsy and the expectations from semantic dementia and other neuroscience findings. Specifically, we found that on simple semantic tasks, the patients' accuracy fell in the normal range, with the exception that some patients with left resection for temporal lobe epilepsy had measurable anomia. Once the semantic assessments were made more challenging, by probing specific-level concepts, lower frequency

  4. Taenia saginata Goeze, 1872 (Platyhelminthes: Cestoda: Taeniidae en un indígena de Tierra del Fuego, Chile

    Directory of Open Access Journals (Sweden)

    Eduardo I. Faúndez

    2015-06-01

    Full Text Available Se entrega el primer registro del céstodo Taenia saginata en un indígena de Tierra del Fuego (Patagonia chilena, correspondiente al año 1902. Se discute la importancia del registro y se entregan ilustraciones del ejemplar.

  5. Modelo matemático para la descripción de la transferencia de calor para tierra vertida

    Directory of Open Access Journals (Sweden)

    Edgardo Jonathan Suárez-Domínguez

    2014-01-01

    Full Text Available La arquitectura de tierra implica procesos constructivos sustentables ya que utiliza materiales vernáculos duraderos cuyos residuos son de bajo impacto al ambiente. La tierra vertida es una técnica a partir de la cual pueden tenerse muros resistentes dentro de la edificación de viviendas pero cuyas propiedades han sido poco evaluadas y representadas a partir de modelos. La transferencia de calor es una de las características más importantes cuando se edifica en zonas calurosas pues implica ciertos niveles de confort para los usuarios. El presente trabajo propone un modelo para determinar la difusividad térmica de tierra vertida con uso potencial para otras determinaciones a diversas temperaturas, algunas implicaciones también son presentadas. Se encontró que el coeficiente de difusividad térmica de muestras de tierra vertida fue de   4.319  10 8 m 2 s 1 , mientras que su calor específico es de 1.1030 kJkg-1K 1 .

  6. Familia nuclear y jefatura del hogar: acceso a la mujer a la tierra en las reformas agrarias

    Directory of Open Access Journals (Sweden)

    Magdalena León

    1999-10-01

    Full Text Available En este texto se analizan las consecuencias que la neutralidad de género ha dejado para la política pública, en el caso específico de las reformas agrarias y acceso de la mujer a la tierra en América Latina.

  7. Severe atrophy of right hepatic lobe simulating right hepatic lobectomy

    International Nuclear Information System (INIS)

    Yeh, C.W.; Strashun, A.; Goldsmith, S.J.

    1981-01-01

    Absence of the right hepatic lobe following blunt abdominal trauma without surgical resection is reported. The usual site of the right hepatic lobe is demonstrated to be occupied by bowel by hepatobiliary imaging

  8. Confabulation and memory impairments following frontal lobe lesions

    OpenAIRE

    Turner, Martha

    2005-01-01

    Neuroimaging studies have provided considerable evidence for frontal lobe involvement in memory processing. Memory impairments arc also frequently reported in patients with frontal lobe lesions. However detailed anatomical localisation is rare, making integration of lesion and imaging findings difficult. An investigation of the functional and anatomical contributions of the frontal lobes to memory was conducted in 42 patients with frontal lobe lesions, examining memory processes identified in...

  9. Dead-ice environments

    DEFF Research Database (Denmark)

    Krüger, Johannes; Kjær, Kurt H.; Schomacker, Anders

    2010-01-01

    glacier environment. The scientific challenges are to answer the key questions. What are the conditions for dead-ice formation? From which sources does the sediment cover originate? Which melting and reworking processes act in the ice-cored moraines? What is the rate of de-icing in the ice-cored moraines...

  10. La tierra en armas de Dávalos-Serrano (o las armas del teatro

    Directory of Open Access Journals (Sweden)

    Marcela Beatriz Sosa

    2003-01-01

    Full Text Available La tierra en armas (1926 constituye un texto enigmático por diversas cuestiones, a pesar de su celebridad –es la obra teatral más famosa de la literatura salteña- y de su aparente transparencia al representar hechos históricos relativos a la gesta de Güemes. El primer enigma es el problema de la autoría, ya que La tierra en armas surge de la escritura en colaboración de Juan Carlos Dávalos y Ramón Serrano, pero en el momento de publicación del texto (1935 aparecerá en la portada sólo el nombre de Dávalos. El gesto editorial de borrar el nombre del segundo autor en esa primera publicación es decisivo para el futuro teatral de Serrano, quien desaparece posteriormente de la escena salteña. La segunda cuestión deriva de la categoría de teatro histórico a la cual pertenece La tierra en armas La ficcionalización de un personaje histórico implica plantear las complejas relaciones que se establecen entre discurso dramático y discurso histórico. Luego de trazar someramente la trayectoria épica de Güemes, se realiza una descripción de la acción dramática y de los fundamentales procedimientos discursivos, como el encadenamiento entre la intriga principal (histórica y la secundaria (sentimental, la mise en abyme de la leyenda de la flor del Ilolay y la visualización escénica del texto. La tercera cuestión incluye el contexto de producción, circulación y recepción del teatro de la época, así como el nivel ideológico, sin los cuales sería imposible postular una interpretación del texto de Dávalos y Serrano como estrategia individual y colectiva de afianzamiento de la identidad.

  11. Respuesta transitoria de las puestas a tierra en la protección contra rayos. Software GTIERRAS

    Directory of Open Access Journals (Sweden)

    Héctor David Gómez Montoya

    2006-01-01

    Full Text Available Se usa un programa computacional desarrollado en Matlab (GTIERRAS que implementa un modelo de base electromagnética, para determinar la impedancia de puesta a tierra de configuraciones arbitrarias y su comportamiento ante excitaciones tipo impulso. Impedancia, corrientes y voltajes, u otras variables eléctricas de sistemas de puesta a tierra se pueden presentar en el dominio de la frecuencia o del tiempo usando la transformada rápida de Fourier. La base general del modelo considerado se usa para valorar no sólo sobretensiones por descargas atmosféricas, sino también, otros transitorios típicos asociados con problemas de compatibilidad electromagnética. Los resultados muestran la influencia de algunas variables en la respuesta del sistema de puesta a tierra y revelan algunas diferencias que se deben tener en cuenta cuando se aplican criterios basados en el desempeño a baja frecuencia, para esfuerzos impulsivos de puestas a tierra. Adicionalmente, se presentan ejemplos de cálculo y comparaciones con resultados de otros autores para ilustrar algunos comportamientos que de ninguna manera son evidentes. Se investiga además, el efecto de la geometría de los electrodos y la resistividad del suelo, así como del frente de onda y el número de puntos de inyección. También se presentan resultados de tensiones de contacto y de paso, así como, el estudio de un sistema de protección contra rayos como ampliación de las aplicaciones del modelo. Finalmente, se derivan algunas conclusiones útiles para el diseño de sistemas de puesta a tierra.

  12. The extratemporal lobe epilepsies in the epilepsy monitoring unit

    Science.gov (United States)

    Dash, Deepa; Tripathi, Manjari

    2014-01-01

    Extratemporal lobe epilepsies (ETLE) are characterized by the epileptogenic foci outside the temporal lobe. They have a wide spectrum of semiological presentation depending upon the site of origin. They can arise from frontal, parietal, occipital lobes and from hypothalamic hamartoma. We discuss in this review the semiology of different types of ETLE encountered in the epilepsy monitoring unit. PMID:24791090

  13. A Rare Case of Craniopharyngioma in the Temporal Lobe

    Directory of Open Access Journals (Sweden)

    Sasan Razmjoo

    2017-01-01

    Full Text Available Herein, we report on a rare case of craniopharyngioma arising in the left temporal lobe with no prior history of head trauma or surgery. There was a solid-cystic mass in the left temporal lobe on MR images. To the best of our knowledge, this is the second case of a craniopharyngioma occurring in the temporal lobe.

  14. Rate of ice accumulation during ice storms

    Energy Technology Data Exchange (ETDEWEB)

    Feknous, N. [SNC-Lavalin, Montreal, PQ (Canada); Chouinard, L. [McGill Univ., Montreal, PQ (Canada); Sabourin, G. [Hydro-Quebec, Montreal, PQ (Canada)

    2005-07-01

    The rate of glaze ice accumulation is the result of a complex process dependent on numerous meteorological and physical factors. The aim of this paper was to estimate the distribution rate of glaze ice accumulation on conductors in southern Quebec for use in the design of mechanical and electrical de-icing devices. The analysis was based on direct observations of ice accumulation collected on passive ice meters. The historical database of Hydro-Quebec, which contains observations at over 140 stations over period of 25 years, was used to compute accumulation rates. Data was processed so that each glaze ice event was numbered in a chronological sequence. Each event consisted of the time series of ice accumulations on each of the 8 cylinders of the ice meters, as well as on 5 of its surfaces. Observed rates were converted to represent the average ice on a 30 mm diameter conductor at 30 m above ground with a span of 300 m. Observations were corrected to account for the water content of the glaze ice as evidenced by the presence of icicles. Results indicated that despite significant spatial variations in the expected severity of ice storms as a function of location, the distribution function for rates of accumulation were fairly similar and could be assumed to be independent of location. It was concluded that the observations from several sites could be combined in order to obtain better estimates of the distribution of hourly rates of ice accumulation. However, the rates were highly variable. For de-icing strategies, it was suggested that average accumulation rates over 12 hour periods were preferable, and that analyses should be performed for other time intervals to account for the variability in ice accumulation rates over time. In addition, accumulation rates did not appear to be highly correlated with average wind speed for maximum hourly accumulation rates. 3 refs., 2 tabs., 10 figs.

  15. RIESGOS CLIMÁTICOS EN LAS TIERRAS VALENCIANAS. INCIDENCIA EN LA ACTIVIDAD AGRARIA

    Directory of Open Access Journals (Sweden)

    Jorge Olcina Cantos

    1995-01-01

    Full Text Available La actividad agraria es el sector económico que, con mayor frecuencia, sufre los efectos de episodios atmosféricos excepcionales que ocasionan graves pérdi- das de cosecha y daños en campos de cultivo e infraestructura agraria (caminos, redes de riego. El campo valenciano no es ajeno a estos eventos, por lo demás condignos a sus condiciones climáticas (lluvias torrenciales, heladas, tormentas de granizo, temporales de viento y sequías, que precisan estudio de causas, consecuencias económicas y localización territorial de sectores de riesgo, para la posterior propuesta de medidas de actuación. La relación de prácticas de defensa puestas en práctica en tierras valencianas ante estos sucesos atmosféri- cos completa el presente estudio.

  16. El regreso de los judíos hispanos a Tierra Santa

    Directory of Open Access Journals (Sweden)

    Enrique Cantera Montenegro

    2004-01-01

    Full Text Available Tras un breve análisis acerca del lugar que la ciudad de Jerusalén y la Tierra Prometida ocupan en el judaismo y en la conciencia colectiva del pueblo judío, y del papel que la Ciudad Santa desempeña como meta de los peregrinos judíos, se estudian los movimientos de migración de los judíos hispanos hacia Palestina, a lo largo de la Edad Media y hasta el siglo XVII.After a brief analysis about the importance of Jerusalem and the Promised Land in the Judaism and in the collective consciousness of the Jewish people, and the role played by the Holy City as a destination for the Jewish pilgrims, the migration movements of the Spanish Jewish to Palestine are studied, along the Middle Ages, until the 17th century.

  17. Substations grounding systems design; Diseno de sistemas de conexion a tierra en subestaciones

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez Sanchez, Raul [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    The grounding systems have been the object of a great number of analytical and experimental studies in the past 15 years, that have given rise to research reports on the several aspects involved in this technique. In this work are briefly reviewed various aspects that is necessary to take into account for its design, analysis and put in operation. [Espanol] Los sistemas de conexion a tierra han sido objeto de gran cantidad de estudios analiticos y experimentales en los pasados quince anos, que han dado origen a informes de investigacion sobre los diversos aspectos que involucra esta tecnica. En este trabajo se revisan brevemente diversos aspectos que es necesario considerar para su diseno, analisis y puesta en operacion.

  18. Soil-water retention curve and beginning of monitoring in Tierra Blanca Joven (TBJ)

    International Nuclear Information System (INIS)

    Chavez, Jose; Lopez, Reynaldo; Kopecky, Lubomir; Landaverde, Jose

    2013-01-01

    The areas covered by the volcanic tephras Tierra Blanca Joven (TBJ) in El Salvador, was suffered mass movements, liquefaction and erosion during the rainy season or when major earthquakes occur, causing important environmental, social and economic losses. A pressure plate, centrifuge and filter paper were used to build a Soil-Water Retention Curve, obtain the characterization of these unsaturated soil, suction values of the fall unit of TBJ. The use of this curve into finite elements software can help to acquire shear strength and permeability properties. The filter paper showed to be a practical method but close to saturation the pressure plate is needed.Scatter results were observed with the centrifuge. The Quickdraw tensiometre (suction) and TMS3 (soil moisture content) are being used in field test to proposed a field methodology for an early warning system for the slopes, that could help in urban planning and risk assessment. (author)

  19. Soil-water retention curve and beginning of monitoring in Tierra Blanca Joven (TBJ)

    International Nuclear Information System (INIS)

    Chavez, Jose A.; Lopez, Reynaldo; Kopecky, Lubomir; Landaverde, Jose

    2013-01-01

    The areas covered by the Tierra Blanca Joven volcanic tephra (TBJ) have suffered hillside movements, liquefaction and erosion causing important environmental, social and economic losses during the rainy season or when earthquakes occur in El Salvador. Suction values of a TBJ drop unit were obtained with the pressure cooker, centrifuge and filter paper to construct the Soil-Water Retention Curve to initiate the characterization of these partially saturated soils. The use of this curve in finite element programs has helped to know the shear stresses and permeability. The filter paper has proved to be a practical method but it is necessary to use the pressure cooker as it becomes saturated. Field tests with tensiometer (suction) and TMS3 (humidity) have been carried out to propose field methodology for an early warning system for hillsides, which can help urban planning and risk studies. (author)

  20. La tierra entre derecho y cultura indígena en Argentina

    Directory of Open Access Journals (Sweden)

    Marzia Rosti

    2009-12-01

    Full Text Available The paper considers the relationships between the indigenous peoples and the Argentinian State since the XIX century until 1994, when it was introduced in the Constitution the provision acknowledging to the indigenous peoples “la posesión y propiedad comunitarias de las tierras que tradicionalmente ocupan”, “la entrega de otras aptas y suficientes para el desarrollo humano” and granting them “la parcipación en la gestión referida a sus recursos naturales y a los demás intereses que los afecten” (art. 75, inc. 17. The paper describes then the issue concerning the claim for indigenous land – raised by the new constitutional provision – and focuses on some significant cases and the more recent jurisprudence on that issue.

  1. Atmospheric electric discharges and grounding systems; Descargas atmosfericas y sistemas de conexion a tierra

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, Elena [ed.] [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    1999-07-01

    In this article the work made by the Institute of Investigaciones Electricas (IIE), in the area of atmospheric electric discharges and grounding connections at Comision Federal de Electricidad (CFE) is presented. The work consisted of the revision of the procedures for the design of transmission lines and substations of CFE from which high indexes of interruptions are reported, from this, a program was defined that allowed to improve the existing designs in CFE. [Spanish] En este articulo se presenta el trabajo realizado por el Instituto de Investigaciones Electricas (IIE), en el area de descargas atmosfericas y conexiones a tierra en Comision Federal de Electricidad (CFE). El trabajo consistio en la revision de los procedimientos de diseno de las areas de transmision y subestaciones de la CFE para los que se reportan altos indices de salidas, a partir de esto se definio un programa que permitio mejorar los disenos existentes en la CFE.

  2. Substations grounding systems design; Diseno de sistemas de conexion a tierra en subestaciones

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez Sanchez, Raul [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    The grounding systems have been the object of a great number of analytical and experimental studies in the past 15 years, that have given rise to research reports on the several aspects involved in this technique. In this work are briefly reviewed various aspects that is necessary to take into account for its design, analysis and put in operation. [Espanol] Los sistemas de conexion a tierra han sido objeto de gran cantidad de estudios analiticos y experimentales en los pasados quince anos, que han dado origen a informes de investigacion sobre los diversos aspectos que involucra esta tecnica. En este trabajo se revisan brevemente diversos aspectos que es necesario considerar para su diseno, analisis y puesta en operacion.

  3. Violence in Tierra Caliente: Inequality, Development and Education Rates in Drug War

    Directory of Open Access Journals (Sweden)

    Raúl Zepeda Gil

    2017-10-01

    Full Text Available The following article presents the effects of social and economic variables on the increment of violence in regional areas of Mexico, upon the intensification of drug prohibitions policies established by former President Felipe Calderon’s administration. This study involved using a data panel of homicides rates with firearms in 31 municipalities of the region of Tierra Caliente for the time period between 2006 to 2012. The results from the study help indicate that agroindustrial development, income inequality, and education rates have been effected in correlation with the increasing of homicidal rates. Also, based on the relevance of the inequality indicators of the study, it can be argued that there is a possible coincidence between the literature of civil wars and sociology of crime in that can be used to explain such cases of violence.

  4. Parábola existencial de la primera Residencia en la Tierra

    Directory of Open Access Journals (Sweden)

    Eduardo Gómez

    1979-12-01

    Full Text Available Como sucede con muchos artistas, es el amor el que hace de Neruda un gran poeta. Su iniciación en la literatura universal data, sin duda, de los "Veinte poemas de amor y una canción desesperada" pero es a partír de "Residencia en la tierra" que logra afianzarse, en profundidad, como uno de los grandes poetas de la lengua castellana y uno de los más extraordinarios líricos de la historia de la literatura. En "Veinte poemas... ", el amor lo hace compenetrarse, estremecido, con la Naturaleza, lo desnuda de convenciones y prejuicios, lo embriaga de gozos dolorosos y le descubre todo el vasto mundo popular del drama sentim ental, depurado y abierto a la profundidad cósmica.

  5. Significações da queda em Residencia en la tierra

    OpenAIRE

    Luigi Patruno

    2011-01-01

    En el presente trabajo, estudio las variantes que asume la imagen de la caída en Residencia en la tierra de Pablo Neruda. Por un lado, la caída se vincula con la decadencia y la muerte y es el movimiento que insiste en la condición frágil del sujeto; por el otro, es imagen de un hundimiento deseable en la memoria, tensión positiva hacia el conocimiento y descenso poético. En mi análisis, procedo hacia una revisión general de los discursos críticos sobre la caída en los poemas de Neruda, propo...

  6. Dynamic perfusion patterns in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Dupont, Patrick; Paesschen, Wim van; Zaknun, John J.; Maes, Alex; Tepmongkol, Supatporn; Locharernkul, Chaichon; Vasquez, Silvia; Carpintiero, Silvina; Bal, C.S.; Dondi, Maurizio

    2009-01-01

    To investigate dynamic ictal perfusion changes during temporal lobe epilepsy (TLE). We investigated 37 patients with TLE by ictal and interictal SPECT. All ictal injections were performed within 60 s of seizure onset. Statistical parametric mapping was used to analyse brain perfusion changes and temporal relationships with injection time and seizure duration as covariates. The analysis revealed significant ictal hyperperfusion in the ipsilateral temporal lobe extending to subcortical regions. Hypoperfusion was observed in large extratemporal areas. There were also significant dynamic changes in several extratemporal regions: ipsilateral orbitofrontal and bilateral superior frontal gyri and the contralateral cerebellum and ipsilateral striatum. The study demonstrated early dynamic perfusion changes in extratemporal regions probably involved in both propagation of epileptic activity and initiation of inhibitory mechanisms. (orig.)

  7. Dynamic perfusion patterns in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Dupont, Patrick; Paesschen, Wim van [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); Zaknun, John J. [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); University Hospital of Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Maes, Alex [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); AZ Groeninge, Nuclear Medicine, Kortrijk (Belgium); Tepmongkol, Supatporn; Locharernkul, Chaichon [Chulalongkorn University, Nuclear Medicine and Neurology, Bangkok (Thailand); Vasquez, Silvia; Carpintiero, Silvina [Fleni Instituto de Investigaciones Neurologicas, Nuclear Medicine, Buenos Aires (Argentina); Bal, C.S. [All India Institute of Medical Sciences, Nuclear Medicine, New Delhi (India); Dondi, Maurizio [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); Ospedale Maggiore, Nuclear Medicine, Bologna (Italy)

    2009-05-15

    To investigate dynamic ictal perfusion changes during temporal lobe epilepsy (TLE). We investigated 37 patients with TLE by ictal and interictal SPECT. All ictal injections were performed within 60 s of seizure onset. Statistical parametric mapping was used to analyse brain perfusion changes and temporal relationships with injection time and seizure duration as covariates. The analysis revealed significant ictal hyperperfusion in the ipsilateral temporal lobe extending to subcortical regions. Hypoperfusion was observed in large extratemporal areas. There were also significant dynamic changes in several extratemporal regions: ipsilateral orbitofrontal and bilateral superior frontal gyri and the contralateral cerebellum and ipsilateral striatum. The study demonstrated early dynamic perfusion changes in extratemporal regions probably involved in both propagation of epileptic activity and initiation of inhibitory mechanisms. (orig.)

  8. MR imaging of temporal lobe meningoencephalocele

    International Nuclear Information System (INIS)

    Tampieri, D.; Leblanc, R.; Melangon, D.; del-Carpio-O'Donovan, R.; Ethier, R.

    1991-01-01

    Basal meningoencephaloceles represent a rare entity, and they may be associated with a variety of midline cerebral abnormalities. The classification of basal meningoencephaloceles is related to their anatomic location. This paper reports experience in 3 patients, 2 who have temporal lobe epilepsy and a bone defect in the region of the foramen rotondum. In these 2 patients the encephalocele and its covering were protruding into the pterygopalatine fossa without any orbital involvement. The third patient presented with cerebrospinal fluid rhinorrhea caused by a transsphenoidal meningoencephalocele. MR imaging is the examination of choice for detecting these lesions since it allows for the visualization of the encephalocele and its meningeal covering as well as the bone defect and associated lesions in the temporal lobes

  9. Constraints on the formation and properties of a Martian lobate debris apron: Insights from high-resolution topography, SHARAD radar data, and a numerical ice flow model

    Science.gov (United States)

    Parsons, Reid; Holt, John

    2016-03-01

    Lobate debris aprons (LDAs) are midlatitude deposits of debris-covered ice formed during one or more periods of glaciation during the Amazonian period. However, little is known about the climate conditions that led to LDA formation. We explore a hypothesis in which a single, extended period of precipitation of ice on the steep slopes of Euripus Mons (45°S, 105°E—east of the Hellas Basin) produced a flowing ice deposit which was protected from subsequent ablation to produce the LDA found at this location. We test this hypothesis with a numerical ice flow model using an ice rheology based on low-temperature ice deformation experiments. The model simulates ice accumulation and flow for the northern and southern lobes of the Euripus Mons LDA using basal topography constrained by data from the Shallow Radar (SHARAD) and a range of ice viscosities (determined by ice temperature and ice grain size). Simulations for the northern lobe of the Euripus LDA produce good fits to the surface topography. Assuming an LDA age of ˜60 Myr and an expected temperature range of 200 to 204 K (for various obliquities) gives an ice grain size of ≈2 mm. Simulations of the southern section produce poor fits to surface topography and result in much faster flow timescales unless multiple ice deposition events or higher ice viscosities are considered.

  10. Bryophyte-cyanobacteria associations during primary succession in recently Deglaciated areas of Tierra del Fuego (Chile).

    Science.gov (United States)

    Arróniz-Crespo, María; Pérez-Ortega, Sergio; De Los Ríos, Asunción; Green, T G Allan; Ochoa-Hueso, Raúl; Casermeiro, Miguel Ángel; de la Cruz, María Teresa; Pintado, Ana; Palacios, David; Rozzi, Ricardo; Tysklind, Niklas; Sancho, Leopoldo G

    2014-01-01

    Bryophyte establishment represents a positive feedback process that enhances soil development in newly exposed terrain. Further, biological nitrogen (N) fixation by cyanobacteria in association with mosses can be an important supply of N to terrestrial ecosystems, however the role of these associations during post-glacial primary succession is not yet fully understood. Here, we analyzed chronosequences in front of two receding glaciers with contrasting climatic conditions (wetter vs drier) at Cordillera Darwin (Tierra del Fuego) and found that most mosses had the capacity to support an epiphytic flora of cyanobacteria and exhibited high rates of N2 fixation. Pioneer moss-cyanobacteria associations showed the highest N2 fixation rates (4.60 and 4.96 µg N g-1 bryo. d-1) very early after glacier retreat (4 and 7 years) which may help accelerate soil development under wetter conditions. In drier climate, N2 fixation on bryophyte-cyanobacteria associations was also high (0.94 and 1.42 µg N g-1 bryo. d-1) but peaked at intermediate-aged sites (26 and 66 years). N2 fixation capacity on bryophytes was primarily driven by epiphytic cyanobacteria abundance rather than community composition. Most liverworts showed low colonization and N2 fixation rates, and mosses did not exhibit consistent differences across life forms and habitat (saxicolous vs terricolous). We also found a clear relationship between cyanobacteria genera and the stages of ecological succession, but no relationship was found with host species identity. Glacier forelands in Tierra del Fuego show fast rates of soil transformation which imply large quantities of N inputs. Our results highlight the potential contribution of bryophyte-cyanobacteria associations to N accumulation during post-glacial primary succession and further describe the factors that drive N2-fixation rates in post-glacial areas with very low N deposition.

  11. Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

    2017-11-01

    Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

  12. Bryophyte-Cyanobacteria Associations during Primary Succession in Recently Deglaciated Areas of Tierra del Fuego (Chile)

    Science.gov (United States)

    Arróniz-Crespo, María; Pérez-Ortega, Sergio; De los Ríos, Asunción; Green, T. G. Allan; Ochoa-Hueso, Raúl; Casermeiro, Miguel Ángel; de la Cruz, María Teresa; Pintado, Ana; Palacios, David; Rozzi, Ricardo; Tysklind, Niklas; Sancho, Leopoldo G.

    2014-01-01

    Bryophyte establishment represents a positive feedback process that enhances soil development in newly exposed terrain. Further, biological nitrogen (N) fixation by cyanobacteria in association with mosses can be an important supply of N to terrestrial ecosystems, however the role of these associations during post-glacial primary succession is not yet fully understood. Here, we analyzed chronosequences in front of two receding glaciers with contrasting climatic conditions (wetter vs drier) at Cordillera Darwin (Tierra del Fuego) and found that most mosses had the capacity to support an epiphytic flora of cyanobacteria and exhibited high rates of N2 fixation. Pioneer moss-cyanobacteria associations showed the highest N2 fixation rates (4.60 and 4.96 µg N g−1 bryo. d−1) very early after glacier retreat (4 and 7 years) which may help accelerate soil development under wetter conditions. In drier climate, N2 fixation on bryophyte-cyanobacteria associations was also high (0.94 and 1.42 µg N g−1 bryo. d−1) but peaked at intermediate-aged sites (26 and 66 years). N2 fixation capacity on bryophytes was primarily driven by epiphytic cyanobacteria abundance rather than community composition. Most liverworts showed low colonization and N2 fixation rates, and mosses did not exhibit consistent differences across life forms and habitat (saxicolous vs terricolous). We also found a clear relationship between cyanobacteria genera and the stages of ecological succession, but no relationship was found with host species identity. Glacier forelands in Tierra del Fuego show fast rates of soil transformation which imply large quantities of N inputs. Our results highlight the potential contribution of bryophyte-cyanobacteria associations to N accumulation during post-glacial primary succession and further describe the factors that drive N2-fixation rates in post-glacial areas with very low N deposition. PMID:24819926

  13. Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

    International Nuclear Information System (INIS)

    Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

    2017-01-01

    Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

  14. MRI findings of temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Nakahara, Ichiro; Yin, Dali; Fukami, Masahiro; Kondo, Seiji; Takeuchi, Juji; Kanemoto, Kousuke; Sengoku, Akira; Kawai, Itsuo

    1992-01-01

    MRI findings were analyzed retrospectively in 46 patients with temporal lobe epilepsy in which the side of epileptogenic focus had been confirmed by EEG studies. T 1 - and T 2 -weighted images were obtained by the use of a 1.0 or 1.5 T superconducting-type MRI machine with a coronal scan perpendicular to the axis of the temporal horn of the lateral ventricle. Additional axial and sagittal scans were performed in some cases. The area of the hippocampal body was measured quantitatively using a computerized image-analysis system in 26 cases in which the hippocampus had been visualized with enough contrast on T 1 -weighted coronal images. Abnormal findings were observed in 31/46 (67%) cases. Hippocampal (HC) and temporal lobe (TL) atrophy were observed in 18/46 (39%) and 23/46 (50%) cases respectively, and the side of the atrophy corresponded with the side of the epileptogenic focus, as confirmed by EEG studies, with specificities of 89% and 74% respectively. A quantitative measurement of the area of the hippocampal body showed unilateral hippocampal atrophy more than 10% in 18/25 (69%) cases (10-25%: 10 cases, 25-50%: 7 cases, 50% 2 abnormality was observed in only 4 cases. Structural lesions were observed in 4 cases including an arachnoid cyst, an astrocytoma in amygdala, the Dandy-Walker syndrome, and tuberous sclerosis, using the more efficient imaging qualities than the CT scan. From these observations, it is apparant that superconducting MRI is extremely useful in the diagnosis of the epileptogenic topography of temporal lobe epilepsy. Particularly, hippocampal atrophy was found to correspond with the side of the epileptogenic focus on EEG with a high specificity; its quantitative evaluation could be one of the most important standards in detecting the operative indications for temporal lobe epilepsy. (author)

  15. Bilateral optical nerve atrophy secondary to lateral occipital lobe infarction.

    Science.gov (United States)

    Mao, Junfeng; Wei, Shihui

    2013-06-01

    To report a phenomenon of optical nerve atrophy secondary to lateral occipital lobe infarction. Two successive patients with unilateral occipital lobe infarction who experienced bilateral optical nerve atrophy during the follow-up underwent cranial imaging, fundus photography, and campimetry. Each patient was diagnosed with occipital lobe infarction by cranial MRI. During the follow-up, a bilateral optic atrophy was revealed, and campimetry showed a right homonymous hemianopia of both eyes with concomitant macular division. Bilateral optic atrophy was related to occipital lobe infarction, and a possible explanation for the atrophy was transneuronal degeneration caused by occipital lobe infarction.

  16. Temporal Lobe Epilepsy Surgery Failures: A Review

    Science.gov (United States)

    Harroud, Adil; Bouthillier, Alain; Weil, Alexander G.; Nguyen, Dang Khoa

    2012-01-01

    Patients with temporal lobe epilepsy (TLE) are refractory to antiepileptic drugs in about 30% of cases. Surgical treatment has been shown to be beneficial for the selected patients but fails to provide a seizure-free outcome in 20–30% of TLE patients. Several reasons have been identified to explain these surgical failures. This paper will address the five most common causes of TLE surgery failure (a) insufficient resection of epileptogenic mesial temporal structures, (b) relapse on the contralateral mesial temporal lobe, (c) lateral temporal neocortical epilepsy, (d) coexistence of mesial temporal sclerosis and a neocortical lesion (dual pathology); and (e) extratemporal lobe epilepsy mimicking TLE or temporal plus epilepsy. Persistence of epileptogenic mesial structures in the posterior temporal region and failure to distinguish mesial and lateral temporal epilepsy are possible causes of seizure persistence after TLE surgery. In cases of dual pathology, failure to identify a subtle mesial temporal sclerosis or regions of cortical microdysgenesis is a likely explanation for some surgical failures. Extratemporal epilepsy syndromes masquerading as or coexistent with TLE result in incomplete resection of the epileptogenic zone and seizure relapse after surgery. In particular, the insula may be an important cause of surgical failure in patients with TLE. PMID:22934162

  17. Occipital lobe infarction and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tagawa, Koichi; Nagata, Ken; Shishido, Fumio (Research Inst. of Brain and Blood Vessels, Akita (Japan))

    1990-08-01

    Even though the PET study revealed a total infarct in the territory of the left PCA in our 3 cases of pure alesia, it is still obscure which part of the left occipital lobe is most closely associated with the occurrence of the pure alexia. In order to elucidate the intralobar localization of the pure alexia, it is needed to have an ideal case who shows an pure alexia due to the localized lesion within the left occipital lobe. Furthermore, high-resolution PET scanner will circumvent the problem in detecting the metabolism and blood flow in the corpus callosum which plays an important role in the pathogenesis. We have shown that the occlusion of the right PCA also produced a left unilateral agnosia which is one of the common neurological signs in the right MCA infarction. To tell whether the responsible lesion for the unilateral spatial agnosia differs between the PCA occlusion and the MCA occlusion, the correlation study should be carried out in a greater number of the subjects. Two distinctive neuropsychological manifestations, cerebral color blidness and prosopagnosia, have been considered to be produced by the bilateral occipital lesion. The PET studies disclosed reduction of blood flow and oxygen metabolism in both occipital lobes in our particular patient who exibited cerebral color blindness and posopagnosia. (author).

  18. Occipital lobe infarction and positron emission tomography

    International Nuclear Information System (INIS)

    Tagawa, Koichi; Nagata, Ken; Shishido, Fumio

    1990-01-01

    Even though the PET study revealed a total infarct in the territory of the left PCA in our 3 cases of pure alesia, it is still obscure which part of the left occipital lobe is most closely associated with the occurrence of the pure alexia. In order to elucidate the intralobar localization of the pure alexia, it is needed to have an ideal case who shows an pure alexia due to the localized lesion within the left occipital lobe. Furthermore, high-resolution PET scanner will circumvent the problem in detecting the metabolism and blood flow in the corpus callosum which plays an important role in the pathogenesis. We have shown that the occlusion of the right PCA also produced a left unilateral agnosia which is one of the common neurological signs in the right MCA infarction. To tell whether the responsible lesion for the unilateral spatial agnosia differs between the PCA occlusion and the MCA occlusion, the correlation study should be carried out in a greater number of the subjects. Two distinctive neuropsychological manifestations, cerebral color blidness and prosopagnosia, have been considered to be produced by the bilateral occipital lesion. The PET studies disclosed reduction of blood flow and oxygen metabolism in both occipital lobes in our particular patient who exibited cerebral color blindness and posopagnosia. (author)

  19. Optical ages indicate the southwestern margin of the Green Bay Lobe in Wisconsin, USA, was at its maximum extent until about 18,500 years ago

    Science.gov (United States)

    Attig, J.W.; Hanson, P.R.; Rawling, J.E.; Young, A.R.; Carson, E.C.

    2011-01-01

    Samples for optical dating were collected to estimate the time of sediment deposition in small ice-marginal lakes in the Baraboo Hills of Wisconsin. These lakes formed high in the Baraboo Hills when drainage was blocked by the Green Bay Lobe when it was at or very near its maximum extent. Therefore, these optical ages provide control for the timing of the thinning and recession of the Green Bay Lobe from its maximum position. Sediment that accumulated in four small ice-marginal lakes was sampled and dated. Difficulties with field sampling and estimating dose rates made the interpretation of optical ages derived from samples from two of the lake basins problematic. Samples from the other two lake basins-South Bluff and Feltz basins-responded well during laboratory analysis and showed reasonably good agreement between the multiple ages produced at each site. These ages averaged 18.2. ka (n= 6) and 18.6. ka (n= 6), respectively. The optical ages from these two lake basins where we could carefully select sediment samples provide firm evidence that the Green Bay Lobe stood at or very near its maximum extent until about 18.5. ka.The persistence of ice-marginal lakes in these basins high in the Baraboo Hills indicates that the ice of the Green Bay Lobe had not experienced significant thinning near its margin prior to about 18.5. ka. These ages are the first to directly constrain the timing of the maximum extent of the Green Bay Lobe and the onset of deglaciation in the area for which the Wisconsin Glaciation was named. ?? 2011 Elsevier B.V.

  20. Clinical study on temporal lobe epilepsy in childhood caused by temporal lobe space occupying lesions

    International Nuclear Information System (INIS)

    Matsuura, Mariko; Oguni, Hirokazu; Funatsuka, Makoto; Osawa, Makiko; Yamane, Fumitaka; Hori, Tomokatsu; Shimizu, Hiroyuki

    2008-01-01

    We studied the clinicoelectrical and neuroimaging features of 11 patients with symptomatic temporal lobe epilepsy (TLE) caused by temporal lobe space occupying lesions (SOLs), and compared its characteristics with those of 19 mesial TLE (MTLE) patients. Brain MRI demonstrated SOLs in the mesiotemporal lobe in 9, and laterotemporal lobe in the remaining 2 patients. Ten of the 11 patients successfully underwent surgery, which revealed tumors in 7 and focal cortical dysplasia in 3 patients. Comparisons of the clinical features between those with space occupying TLE (SOTLE) and MTLE showed that both conditions shared the same clinical seizure manifestations such as gastric uprising sensation or ictal fear and a favorable response to surgery. However, the patients with SOTLE had fewer febrile convulsion, and more frequent seizure recurrences as well as TLE EEG discharges and associations of the monophasic clinical course than those with MTLE. In addition, the MRI findings were characterized by unilateral hippocampal atrophy in MTLE and expanding or SOLs in the SOTLE group. Children with complex partial seizures of suspected temporal lobe origin should undergo extensive neuroimaging evaluation. (author)

  1. Stochastic ice stream dynamics.

    Science.gov (United States)

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-09

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution.

  2. Sea Ice Ecosystems

    Science.gov (United States)

    Arrigo, Kevin R.

    2014-01-01

    Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.

  3. Knowing for controlling: ecological effects of invasive vertebrates in Tierra del Fuego Conocer para controlar: efectos ecológicos de vertebrados invasores en Tierra del Fuego

    Directory of Open Access Journals (Sweden)

    CLAUDIA A SILVA

    2008-03-01

    Full Text Available The Tierra del Fuego (TDF archipelago is recognized as part o the last places on Earth that may still be considered wild. However, this condition may be threatened by the large number of invasive species present on the archipelago. These species can have significant effects on the ecology of the invaded ecosystems, at the genetic as well as at population, community and ecosystem levels. The aim of this study is to, by a bibliographic review, systematize existing information on the ecological impacts these species would be having on the TDF archipelago and detect information gaps in order to orient future research and effective management programs on these species. We restricted our review to vertebrate, non-marine invaders. We determined which species have invaded TDF, described their impacts on the archipelago and evaluated their potential impacts; this last issue was determined by reviewing some of the impacts these species have had in other geographic areas. Our findings indicate that at least nine vertebrate species (Salmo trutta, Salvelinus fontinalis, Oncorhynchus mykiss, Castor canadensis, Ondatra zibethicus, Oryctolagus cuniculus, Pseudalopex griseus, Mustela vison and Sus seroja have wild populations established away from human settlements in TDF. There is some scientific evidence on ecological impacts on the area for only five of these invaders, with the American beaver (Castor canadensis being the species monopolizing the greatest number of studies. These results contrast with the recognition, both in TDF and worldwide, of the potential of most of these species to cause significant ecological impacts, which makes it unlikely that the lack of verified impacts on TDF reflects an absence of significant effects of these invaders on the archipelago. We suggest that future research should focus on determining population density and distribution of these and other (i.e., feral species invasive vertebrates, as well as their impacts mainly on

  4. Ross Ice Shelf, Antarctic Ice and Clouds

    Science.gov (United States)

    1991-01-01

    In this view of Antarctic ice and clouds, (56.5S, 152.0W), the Ross Ice Shelf of Antarctica is almost totally clear, showing stress cracks in the ice surface caused by wind and tidal drift. Clouds on the eastern edge of the picture are associated with an Antarctic cyclone. Winds stirred up these storms have been known to reach hurricane force.

  5. Crevasse-squeeze ridge corridors: Diagnostic features of late-stage palaeo-ice stream activity

    Science.gov (United States)

    Evans, David J. A.; Storrar, Robert D.; Rea, Brice R.

    2016-04-01

    A 200-km-long and 10-km-wide linear assemblage of till-filled geometrical ridges on the bed of the Maskwa palaeo-ice stream of the late Wisconsinan southwest Laurentide Ice Sheet are interpreted as crevasse-squeeze ridges (CSR) developed during internal flow unit reorganization, immediately prior to ice stream shutdown. Ridge orientations are predominantly orientated WNW-ESE, with a subordinate WSW-ENE alignment, both indicative of ice fracture development transverse to former ice stream flow, as indicated by NNE-SSW aligned MSGL. Subglacial till injection into basal and/or full depth, mode I and II crevasses occurred at the approximate centreline of the ice stream, in response to extension and fracturing. Landform preservation indicates that this took place during the final stages of ice streaming, immediately prior to ice stream shutdown. This linear zone of ice fracturing therefore likely represents the narrowing of the fast-flowing trunk, similar to the plug flow identified in some surging valley glaciers. Lateral drag between the final active flow unit and the slower moving ice on either side is likely recorded by the up-ice bending of the CSR limbs. The resulting CSR corridor, here related to an individual ice stream flow unit, constitutes a previously unreported style of crevasse infilling and contrasts with two existing CSR patterns: (1) wide arcuate zones of CSRs related to widespread fracturing within glacier surge lobes; and (2) narrow concentric arcs of CSRs and recessional push moraines related to submarginal till deformation at active temperate glacier lobes.

  6. Magnetic resonance imaging in temporal lobe epilepsy. Usefulness for the etiological diagnosis of temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Mohamed, A.; Lueders, H.O.

    2000-01-01

    With improvement in magnetic resonance (MR) imaging techniques, the ability to identify lesions responsible for temporal lobe epilepsy has increased. MR imaging has also enabled the in vivo diagnosis of hippocampal sclerosis. Brain tumors are responsible for 2-4% of epilepsies in adult population and 10-20% of medically intractable epilepsy. The sensitivity of MR imaging in the diagnosis of tumors and other lesions of the temporal lobe (vascular malformations, etc.) is around 90%. Both hippocampal sclerosis and other temporal lobe lesions are amenable to surgical therapy with excellent postsurgical seizure outcome. In this article, we characterize and underline distinguishing features of the different pathological entities. We also suggest an approach to reviewing the MR images of an epileptic patient. (author)

  7. A natural ice boom

    Energy Technology Data Exchange (ETDEWEB)

    Hopper, H.R. [Manitoba Hydro, Winnipeg, MB (Canada)

    1998-10-01

    Planning for ice jams and ice movements are critical on the Nelson River in northern Manitoba in designing cofferdams. Experience on the St. Lawrence River demonstrated the possibility of exercising some control over ice action by judicious placement of log booms or ice control structures. The success of experiments with man-made controls led to field tests in which an ice sheet of sufficient magnitude and competence was introduced into the open water stream of the Nelson River. The ice sheet was subsequently jammed in a narrow channel, thereby creating a natural ice bridge or boom upstream of a proposed hydro development. Under favourable conditions, this boom would initiate the progression of the ice cover from its location upstream, cutting off the downstream reach from the ice producing potential of the upstream reach. Although ice would still be generated downstream, the length of the reach between the ice boom and the development site would be short enough that ice jamming at the development site would never occur. Although problems in blasting prevented the introduction of a competent ice sheet into the main stream of the river at the location chosen, sufficient confidence in the theory was gained to warrant further consideration. 4 refs., 1 tab., 10 figs.

  8. Forecast Icing Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Forecast Icing Product (FIP) is an automatically-generated index suitable for depicting areas of potentially hazardous airframe icing. The FIP algorithm uses...

  9. Current Icing Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Current Icing Product (CIP) is an automatically-generated index suitable for depicting areas of potentially hazardous airframe icing. The CIP algorithm combines...

  10. Centro de Control de Tierra para Colaboración de Vehículos Autónomos Marinos

    Directory of Open Access Journals (Sweden)

    J.A. Bonache Seco

    2017-12-01

    donde la incorporación del operador en la supervisión y control de las maniobras de los vehículos es un requisito imprescindible para dar seguridad y confianza a la operación realizada. Finalmente, se presenta un caso de uso del Centro de Control de Tierra donde se realiza una maniobra de seguimiento entre dos vehículos autónomos de superficie.

  11. A new genus and new species of felt scales (Homoptera: Coccinea: Eriococcidae from Tierra del Fuego (Chile

    Directory of Open Access Journals (Sweden)

    Ilya A. Gavrilov-Zimin

    2016-10-01

    Full Text Available Telmatococcus igniumterrae gen. nov. et sp. nov. is described and illustrated based on the material collected from a sphagnum bog in the extreme southern part of South America (Tierra del Fuego. The new monotypic genus differs from all known genera of Eriococcidae in having short cylindrical truncated setae of the anal apparatus and pouches with numerous quinquelocular pores near the anal apparatus. The habitat of the new taxon is characterized.

  12. Sputtering of water ice

    International Nuclear Information System (INIS)

    Baragiola, R.A.; Vidal, R.A.; Svendsen, W.; Schou, J.; Shi, M.; Bahr, D.A.; Atteberrry, C.L.

    2003-01-01

    We present results of a range of experiments of sputtering of water ice together with a guide to the literature. We studied how sputtering depends on the projectile energy and fluence, ice growth temperature, irradiation temperature and external electric fields. We observed luminescence from the decay of H(2p) atoms sputtered by heavy ion impact, but not bulk ice luminescence. Radiolyzed ice does not sputter under 3.7 eV laser irradiation

  13. Fate of a broad spectrum of perfluorinated compounds in soils and biota from Tierra del Fuego and Antarctica

    International Nuclear Information System (INIS)

    Llorca, Marta; Farré, Marinella; Tavano, Máximo Sebastián; Alonso, Bruno; Koremblit, Gabriel; Barceló, Damià

    2012-01-01

    In this study, the presence of 18 perfluorinated compounds was investigated in biota and environmental samples from the Antarctica and Tierra de Fuego, which were collected during a sampling campaign carried out along February and March 2010. 61 samples were analysed including fish, superficial soils, guano, algae, dung and tissues of Papua penguin by liquid chromatography coupled to tandem mass spectrometry. The concentrations of PFCs were ranging from 0.10 to 240 ng/g for most of the samples except for penguin dung, which presented levels between 95 and 603 ng/g for perfluorooctane sulfonate, and guano samples from Ushuaia, with concentration levels of 1190–2480 ng/g of perfluorohexanoic acid. PFCs acids presented, in general, the highest levels of concentration and perfluorooctanesulfonate was the most frequently found compound. The present study provides a significant amount of results, which globally supports the previous studies, related to the transport, deposition, biodegradation and bioaccumulation patterns of PFCs. - Highlights: ► 61 samples from the Antarctica and Tierra de Fuego analysed for the presence of 18 perfluorinated compounds. ► Acid compounds presented the highest levels of concentration and perfluorooctane sulfonate was the most frequently found. ► Concentrations in algae much higher than those in soils. ► Data supporting existing models for the transport, deposition, biodegradation and bioaccumulation patterns are presented. - 18 perfluorinated compounds assessed in biota and environmental samples from Tierra del Fuego and the Antarctica. Concentrations related to Compounds properties.

  14. Género y arrebato de tierras: el caso del nuevo aeropuerto internacional de Ciudad de México

    Directory of Open Access Journals (Sweden)

    Verónica Vázquez García

    2018-09-01

    Full Text Available En este artículo se explora la dinámica de género del arrebato de tierras en el municipio de Atenco, Estado de México, para la construcción del nuevo aeropuerto internacional de la Ciudad de México. A partir de datos obtenidos mediante la sistematización de expedientes ejidales, la observación participante y las entrevistas a profundidad, se analiza la discriminación de género en la venta de tierras y las estrategias de las mujeres para enfrentarla. El artículo contribuye a estudiar la infraestructura de comunicaciones, un sector poco teorizado; a utilizar información documental, principalmente testimonial, y a visibilizar los efectos de género y el papel de las mujeres en la resistencia. Se muestra que los agentes del arrebato de tierras son el Estado, el capital y las estructuras comunitarias que reproducen la inequidad de género, para concentrar la riqueza y los privilegios políticos en manos predominantemente masculinas.

  15. Seguimiento al comportamiento del mercado de tierras rurales a través de un GIS, Santander Colombia

    Directory of Open Access Journals (Sweden)

    Ricardo Lozano-Botache

    2016-01-01

    Full Text Available A pesar de los marcos legales y políticas públicas, en algunos países, los derechos de propiedad sobre la tierra siguen siendo usurpados o impedidos con métodos violentos. Este trabajo de investigación, desde el marco de referencia de la Administración de Tierras, el Neoinstitucionalismo y las herramientas computacionales –conocidas genéricamente como Sistemas de Información Geográfica (GIS, por sus siglas en inglés– presenta un modelo de observación regional de precios que, por la secuencia de datos y su proceso informático, puede mantenerse a través del tiempo como referente en procesos agrarios de restitución de tierras a víctimas del despojo, así como en la ejecución de proyectos de desarrollo social o económico.

  16. The perceived image of Tierra del Fuego (Argentina in travel stories published by “TravelPod”

    Directory of Open Access Journals (Sweden)

    Patricia Andrea Mosti

    2017-07-01

    environmental conditions, with inhospitable landscapes and, by all appearances, a pristine ecosystem. Together these things form a constitutive part the territorial identity of southern Patagonia. The cartography, the scientific expeditions, the religious missions, the journalism and the literature played an important role in the diffusion and permanency of these representations. In modern Western societies, companies have positioned the concept as a powerful tourist resource, capable of motivating travelers coming to Tierra del Fuego. The present communication proposes an approximation to the perceived image of Tierra del Fuego, according to tourists’ statements in trip blogs, taking these chronicles from sources posted on the site Travelpod. The aim is to examine the contents of the perceived image and to investigate the ways that the concept “End of the World” is resignified. The tourists’ testimonies appeal always to the idea of the End of the World; these representations can be condensed to two dimensions, the one linked to physical – geographical aspects and another that recreates symbolic contents. In the perceived images of Tierra del Fuego, there is an intermingling of the archaic, the legend and the distance, the impregnable vastness of the nature and the recollection of heroic expeditions.

  17. Negociando la tierra: empresas extranjeras, minería a gran escala y derechos humanos en Colombia

    Directory of Open Access Journals (Sweden)

    Juan David Velasco

    2014-01-01

    Full Text Available La adquisición masiva de tierras por parte de empresas extranjeras en países africanos, asiáticos y latinoamericanos refleja una nueva fase del capitalismo global (Sassen, 2013. Colombia no ha escapado a esta lógica mundial del capitalismo, pues en la última década la influencia de las empresas extranjeras en el mercado de tierras ha sido notoria. En esa lógica, este artículo compara, desde un enfoque de Derechos Humanos, las prácticas de adquisición de tierras de tres compañías extranjeras que han explotado carbón a cielo abierto en La Guajira y Cesar. Los resultados indican que la formalidad de la propiedad agraria y las restricciones institucionales de las empresas —asociadas al gobierno corporativo, la participación en bolsa de valores y el veto de compradores internacionales—influyen significativamente en el respeto a los derechos humanos.

  18. PERSPECTIVAS DEL PROCESO DE TITULACIÓN DE TIERRAS EN LA COMUNIDAD CAMPESINA SAN JUAN DE MIRAFLORES, 2011

    Directory of Open Access Journals (Sweden)

    Roger Ricardo Ríos Ramirez

    2014-12-01

    Full Text Available El objetivo del trabajo fue evaluar las perspectivas hacia la titulación de tierras en la Comunidad Campesina San Juan de Miraflores (CCSJM.El estudio fue de tipo descriptivo, con un diseño no experimental transversal. Se aplicó un cuestionario estructurado para evaluar perspectivas a una muestra de 353 comuneros seleccionados de manera aleatoria, estratificada y proporcional, previa validación de expertos y con una confiabilidad alfa de Cronbach α =  0.944.En la CCSJM, las parcelas no tienen las características necesarias para que la agricultura o ganadería se desarrollen, asimismo la actividad campesina no es la principal actividad económica. Asimismo, los comuneros de la CCSJM muestran una perspectiva favorable hacia la titulación de tierras.Por lo tanto, consideramos imperante el proceso de titulación de tierras y la promoción de opciones laborales distintas a las que usualmente realiza un campesino.

  19. Origin of frontal lobe spikes in the early onset benign occipital lobe epilepsy (Panayiotopoulos syndrome).

    Science.gov (United States)

    Leal, Alberto J R; Ferreira, José C; Dias, Ana I; Calado, Eulália

    2008-09-01

    Early onset benign occipital lobe epilepsy (Panayiotopoulos syndrome [PS]) is a common and easily recognizable epilepsy. Interictal EEG spike activity is often multifocal but most frequently localized in the occipital lobes. The origin and clinical significance of the extra-occipital spikes remain poorly understood. Three patients with the PS and interictal EEG spikes with frontal lobe topography were studied using high-resolution EEG. Independent component analysis (ICA) was used to decompose the spikes in components with distinct temporal dynamics. The components were mapped in the scalp with a spline-laplacian algorithm. The change in scalp potential topography from spike onset to peak, suggests the contribution of several intracranial generators, with different kinetics of activation and significant overlap. ICA was able to separate the major contributors to frontal spikes and consistently revealed an early activating group of components over the occipital areas in all the patients. The local origin of these early potentials was established by the spline-laplacian montage. Frontal spikes in PS are consistently associated with early and unilateral occipital lobe activation, suggesting a postero-anterior spike propagation. Frontal spikes in the PS represent a secondary activation triggered by occipital interictal discharges and do not represent an independent focus.

  20. Rock Magnetic Properties of Laguna Carmen (Tierra del Fuego, Argentina): Implications for Paleomagnetic Reconstruction

    Science.gov (United States)

    Gogorza, C. G.; Orgeira, M. J.; Ponce, F.; Fernández, M.; Laprida, C.; Coronato, A.

    2013-05-01

    We report preliminary results obtained from a multi-proxy analysis including paleomagnetic and rock-magnetic studies of two sediment cores of Laguna Carmen (53°40'60" S 68°19'0" W, ~83m asl) in the semiarid steppe in northern Tierra del Fuego island, Southernmost Patagonia, Argentina. Two short cores (115 cm) were sampled using a Livingstone piston corer during the 2011 southern fall. Sediments are massive green clays (115 to 70 cm depth) with irregularly spaced thin sandy strata and lens. Massive yellow clay with thin sandy strata continues up to 30 cm depth; from here up to 10 cm yellow massive clays domain. The topmost 10 cm are mixed yellow and green clays with fine sand. Measurements of intensity and directions of Natural Remanent Magnetization (NRM), magnetic susceptibility, isothermal remanent magnetization, saturation isothermal remanent magnetization (SIRM), back field and anhysteretic remanent magnetization at 100 mT (ARM100mT) were performed and several associated parameters calculated (ARM100mT/k and SIRM/ ARM100mT). Also, as a first estimate of relative magnetic grain-size variations, the median destructive field of the NRM (MDFNRM), was determined. Additionally, we present results of magnetic parameters measured with vibrating sample magnetometer (VSM). The stability of the NRM was analyzed by alternating field demagnetization. The magnetic properties have shown variable values, showing changes in both grain size and concentration of magnetic minerals. It was found that the main carrier of remanence is magnetite with the presence of hematite in very low percentages. This is the first paleomagnetic study performed in lakes located in the northern, semiarid fuegian steppe, where humid-dry cycles have been interpreted all along the Holocene from an aeolian paleosoil sequence (Orgeira et el, 2012). Comparison between paleomagnetic records of Laguna Carmen and results obtained in earlier studies carried out at Laguna Potrok Aike (Gogorza et al., 2012

  1. ANÁLISIS PRELIMINAR DEL TRATAMIENTO FISICOQUÍMICO Y BIOLÓGICO DEL ACEITE DIELÉCTRICO PRESENTE EN TIERRA FULLER

    Directory of Open Access Journals (Sweden)

    EDISON ALEXANDER AGUDELO

    2011-01-01

    Full Text Available Este estudio evalúa dos tecnologías: una físico-química y otra biológica, que buscan eliminar la contaminación por el aceite dieléctrico presente en la tierra Fuller, Buscando con ello gestionar de forma ambientalmente adecuada este residuo peligroso. Para la Tecnología físico-química, se usó hexano como solvente y se alcanzó de manera preliminar remociones del aceite dieléctrico del orden del 87% en la tierra Fuller tratada, con una relación tierra Fuller: solvente de 1:8 p/v, una velocidad de agitación de 100 rpm y un tiempo de contacto de 30 minutos. La calidad del aceite dieléctrico recuperado no es apta para su uso en equipos eléctricos, por su baja rigidez dieléctrica, baja densidad y color desfavorable. La tierra Fuller recuperada alcanzó una densidad aparente de 0.623 gr/ml, una densidad real de 2.231 gr/ml y una porosidad de 72.075 %, lo que indica al menos preliminarmente que dicha tierra está muycercana en sus características físicas a la tierra fuller limpia. Para la tecnología biológica se trató la tierra contaminada en un reactor biológico de tierra activada, evaluando la velocidad de agitación y el tiempo de degradación necesario para alcanzar niveles de contaminación adecuados que permitan disponer el residuo en un relleno sanitario convencional sin riesgo para la salud de los ecosistemas y el ser humano, esta fase aún se encuentra en experimentación y los resultados dependen del análisis cromatográfi co del aceite dieléctrico que permanece en la tierra Fuller tratada, en el cual se hará el seguimiento de 10 especies que son clave dentro de este producto, debido a su cantidad y/o toxicidad , falta comprobar la calidad química de la tierra fuller y del aceite dieléctrico recuperados en el tratamiento físico-químico, y validar el proceso biológico para degradar el aceite dieléctrico.

  2. Anterior Temporal Lobe Morphometry Predicts Categorization Ability.

    Science.gov (United States)

    Garcin, Béatrice; Urbanski, Marika; Thiebaut de Schotten, Michel; Levy, Richard; Volle, Emmanuelle

    2018-01-01

    Categorization is the mental operation by which the brain classifies objects and events. It is classically assessed using semantic and non-semantic matching or sorting tasks. These tasks show a high variability in performance across healthy controls and the cerebral bases supporting this variability remain unknown. In this study we performed a voxel-based morphometry study to explore the relationships between semantic and shape categorization tasks and brain morphometric differences in 50 controls. We found significant correlation between categorization performance and the volume of the gray matter in the right anterior middle and inferior temporal gyri. Semantic categorization tasks were associated with more rostral temporal regions than shape categorization tasks. A significant relationship was also shown between white matter volume in the right temporal lobe and performance in the semantic tasks. Tractography revealed that this white matter region involved several projection and association fibers, including the arcuate fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, and inferior longitudinal fasciculus. These results suggest that categorization abilities are supported by the anterior portion of the right temporal lobe and its interaction with other areas.

  3. Anterior Temporal Lobe Morphometry Predicts Categorization Ability

    Directory of Open Access Journals (Sweden)

    Béatrice Garcin

    2018-02-01

    Full Text Available Categorization is the mental operation by which the brain classifies objects and events. It is classically assessed using semantic and non-semantic matching or sorting tasks. These tasks show a high variability in performance across healthy controls and the cerebral bases supporting this variability remain unknown. In this study we performed a voxel-based morphometry study to explore the relationships between semantic and shape categorization tasks and brain morphometric differences in 50 controls. We found significant correlation between categorization performance and the volume of the gray matter in the right anterior middle and inferior temporal gyri. Semantic categorization tasks were associated with more rostral temporal regions than shape categorization tasks. A significant relationship was also shown between white matter volume in the right temporal lobe and performance in the semantic tasks. Tractography revealed that this white matter region involved several projection and association fibers, including the arcuate fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, and inferior longitudinal fasciculus. These results suggest that categorization abilities are supported by the anterior portion of the right temporal lobe and its interaction with other areas.

  4. Occurrence of the lobe plasma at lunar distance

    International Nuclear Information System (INIS)

    Hardy, D.A.; Hills, H.K.; Freeman, J.W.

    1979-01-01

    Recent analysis has confirmed and expanded the characterization of the lobe plasma, the extension of the 'boundary layer' and 'plasma mantle' to lunar distances. Careful statistical analysis has verified that Magnetic Field (1MF). When the moon is in the dawnside of the northern lobe or duskside of the southern lobe, the probability for observation of the lobe plasma is greatly increased when, in the hour preceding, the IMF has had a positive y component. Conversely, when the moon is in the duskside of the northern lobe or dawnside of the southern lobe, the probability for observation is much increased when the IMF has a negative y component. Analysis of lobe plasma data in conjunction with high time resolution IMF data has shown the probability of observation also is greater with a southward pointing IMF. The observed correlations with the y and z components the IMF reflect the fact that the asymmetry and changes in magnitude of the polar cap electric field induced by the IMF extends to lunar distances and determines the depth into the tail to which the ions can drift. Generally, the lobe plasma is observed sporadically for a full day after the moon has entered the tail and a full day before the last magnetopause crossing as it exits the tail. An average extent of approx.8--10R/sub e/ inward from the magnetopause is inferred; however, the lobe plasma has been seen all across the tail

  5. Surgical Considerations of Intractable Mesial Temporal Lobe Epilepsy

    Science.gov (United States)

    Boling, Warren W.

    2018-01-01

    Surgery of temporal lobe epilepsy is the best opportunity for seizure freedom in medically intractable patients. The surgical approach has evolved to recognize the paramount importance of the mesial temporal structures in the majority of patients with temporal lobe epilepsy who have a seizure origin in the mesial temporal structures. For those individuals with medically intractable mesial temporal lobe epilepsy, a selective amygdalohippocampectomy surgery can be done that provides an excellent opportunity for seizure freedom and limits the resection to temporal lobe structures primarily involved in seizure genesis. PMID:29461485

  6. Surgical Considerations of Intractable Mesial Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Warren W. Boling

    2018-02-01

    Full Text Available Surgery of temporal lobe epilepsy is the best opportunity for seizure freedom in medically intractable patients. The surgical approach has evolved to recognize the paramount importance of the mesial temporal structures in the majority of patients with temporal lobe epilepsy who have a seizure origin in the mesial temporal structures. For those individuals with medically intractable mesial temporal lobe epilepsy, a selective amygdalohippocampectomy surgery can be done that provides an excellent opportunity for seizure freedom and limits the resection to temporal lobe structures primarily involved in seizure genesis.

  7. Channel systems and lobe construction in the Mississippi Fan

    Science.gov (United States)

    Garrison, L. E.; Kenyon, Neil H.; Bouma, A.H.

    1982-01-01

    Morphological features on the Mississippi Fan in the eastern Gulf of Mexico were mapped using GLORIA II, a long-range side-scan sonar system. Prominent is a sinuous channel flanked by well-developed levees and occasional crevasse splays. The channel follows the axis and thickest part of the youngest fan lobe; seismic-reflection profiles offer evidence that its course has remained essentially constant throughout lobe development. Local modification and possible erosion of levees by currents indicates a present state of inactivity. Superficial sliding has affected part of the fan lobe, but does not appear to have been a factor in lobe construction. ?? 1982 A. M. Dowden, Inc.

  8. Helicopter Icing Review.

    Science.gov (United States)

    1980-09-01

    helicopter (i.e. in an icing tunnel or engine test cell ) and therefore can be subjected to controlled icing where spe- cific problems can be safely...evaluation. 69 2.2.5.2 Ice Protection Systems Demonstration Many of the systems noted in 2.2.5.1 can be evaluated in icing test cells or icing wind tunnels...Figure 2-32 illustrates a typical rotor deice system control arrangement. 104 (N >4 A.dO INaH -E- C4) uo U En 9 E-1 H m I ~z O 04 04iH U 0 El4 E-f C E

  9. Tierras estatales y desigualdad de género en Uruguay=State lands and gender inequality in Uruguay

    Directory of Open Access Journals (Sweden)

    Paula Florit O`Neill

    2017-06-01

    Full Text Available Resumen En Uruguay, el Instituto Nacional de Colonización (INC es la institución encargada de la adjudicación de tierra por parte del Estado, orientado a la distribución racional de la tierra y su acceso por parte de la población rural más vulnerable. A partir del año 2005, atravesó una reforma que jerarquizó su rol en las políticas de Estado y gestó un nuevo modelo de adjudicación de tierras: las experiencias asociativas. Ese mismo año, el nuevo gobierno impulsó la transversalización de género en el Estado, impulso que anclara en el INC a partir del 2013. Este artículo analiza desde una perspectiva de género la reforma refundacional y la nueva política de tierras, develando la ceguera de género de la reforma y evidenciando desafíos pendientes para la transversalización de género en el diseño de la principal modalidad de adjudicación de tierras públicas.      Abstract In Uruguay, the National Institute of Colonization is the institution resposible for the adjudication of land by the State, aimed at the rational distribution of land and its access by the most vulnerable rural population. Since 2005, the INC went through a reform that prioritized its role in the policies of the State and created a new model of land adjudication: associative experiences of colonization. In that same year, the new government promoted gender mainstreaming in the State, impulse that took roots in the INC from 2013 onwards. This article analyzes from a gender perspective the refounding reform and the new land policy, unveiling the gender blindness of the reform and highlighting pending challenges for gender mainstreaming in the design of the main public land adjudication modality.

  10. Ice slurry applications

    Energy Technology Data Exchange (ETDEWEB)

    Kauffeld, M. [Karlsruhe University of Applied Sciences, Moltkestr. 30, 76133 Karlsruhe (Germany); Wang, M.J.; Goldstein, V. [Sunwell Technologies Inc., 180 Caster Avenue, Woodbridge, L4L 5Y (Canada); Kasza, K.E. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2010-12-15

    The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single-phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology. (author)

  11. Health at the Extremes. Epidemiological and Sanitary Scene in Tierra del Fuego, 1890-1930

    Directory of Open Access Journals (Sweden)

    Romina Casali

    2014-05-01

    Full Text Available Objective: To characterize the epidemiological and sanitary conditions of the city of Ushuaia (National Territory of Tierra del Fuego at a key time in its history- a time in which interethnic contact and the consolidation of the Argentine nation-state were intensified as two parallel and related processes. Materials and methods: All death certificates available for the period 1890-1930 were analyzed, as well as relevant government documents and secondary sources in order to ob¬tain the health profile of the city and its relationship with the country in the following aspects: type of epidemiological phase, mortality rates, population structure, and the structure in health¬care. Conclusions: There was a great relevance of infectious diseases, and specially tuberculosis, among the population of the city in general, and among the indigenous and criminal population in particular. This epidemiological profile showed the shortcomings of a national health system that was trying to establish at the time, especially in a region difficult to reach.

  12. Arriendo y desigualdad en las tierras altas de Jujuy (Argentina a fines del siglo XIX

    Directory of Open Access Journals (Sweden)

    Cecilia A. Fandos

    2016-01-01

    Full Text Available Las estructuras agrarias originadas en los procesos más generales de desarrollo capitalista y de redefinición de los derechos de propiedad del siglo XIX en la provincia argentina de Jujuy, resultaron favorables a la formación de importantes latifundios. La contracara de esa fuerte concentración de tierras fue la existencia de un amplio sector de la sociedad que compartía la condición de arrendatarios. De ahí que en este artículo nos proponemos estudiar a los arrendatarios como productores –la riqueza y los ingresos brutos procedentes de la explotación rural que tenían a su cargo– a fin de indagar su capacidad de remuneración, contrastándolos entre sí y con otras situaciones sociales. Para ello, analizamos dos casos que tratan el asunto de sus relaciones de producción en el arriendo. A partir de fuentes fiscales y censales de la década de 1890 que contienen datos de la actividad agropecuaria y de informes sobre la rentabilidad de los distintos productos de origen agrícola o ganaderos de la misma época, reconstruimos el ingreso bruto de esas unidades para cada uno de los actores involucrados en ellas y analizamos los niveles de desigualdad para ese conjunto social.

  13. Functional ecology of soil microbial communities along a glacier forefield in Tierra del Fuego (Chile).

    Science.gov (United States)

    Fernández-Martínez, Miguel A; Pointing, Stephen B; Pérez-Ortega, Sergio; Arróniz-Crespo, María; Green, T G Allan; Rozzi, Ricardo; Sancho, Leopoldo G; de Los Ríos, Asunción

    2016-09-01

    A previously established chronosequence from Pia Glacier forefield in Tierra del Fuego (Chile) containing soils of different ages (from bare soils to forest ones) is analyzed. We used this chronosequence as framework to postulate that microbial successional development would be accompanied by changes in functionality. To test this, the GeoChip functional microarray was used to identify diversity of genes involved in microbial carbon and nitrogen metabolism, as well as other genes related to microbial stress response and biotic interactions. Changes in putative functionality generally reflected succession-related taxonomic composition of soil microbiota. Major shifts in carbon fixation and catabolism were observed, as well as major changes in nitrogen metabolism. At initial microbial dominated succession stages, microorganisms could be mainly involved in pathways that help to increase nutrient availability, while more complex microbial transformations such as denitrification and methanogenesis, and later degradation of complex organic substrates, could be more prevalent at vegetated successional states. Shifts in virus populations broadly reflected changes in microbial diversity. Conversely, stress response pathways appeared relatively well conserved for communities along the entire chronosequence. We conclude that nutrient utilization is likely the major driver of microbial succession in these soils. [Int Microbiol 19(3):161-173 (2016)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

  14. EVALUATION OF INSECTICIDES FOR PEST CONTROL IN MANGO (Mangifera indica L. IN TIERRA CALIENTE, GUERRERO, MEXICO

    Directory of Open Access Journals (Sweden)

    Yuridia Duran

    2017-12-01

    Full Text Available The mango crop is attacked by various pests, in Arcelia, Tierra Caliente, Guerrero, Mexico. Scale insects (Hemiptera and thrips (Thysanoptera were identified, the pesticides imidacloprid, spinosad, sulfur and mineral oil were tested against them, as well as their effect on fruit quality, using pest action thresholds. The thrips Frankliniella invasor appeared in the highest populations, but F. difficilis, F. occidentalis, F. fortissima, F. cephalica, Leptothrips macconnelli, L. bifurcatus and L. theobromae were also found. It was observed that mineral oil maintained the lowest populations and least damage in fruit; thrips species did not cause significant damage because they were seasonal pests that only occur when soft tissue is available in plants and once this tissue becomes unavailable populations diminish without the need of insecticides.  The mite Cisaberoptus kenyae was identified, which in high populations can cause crop damage; for its control sulfur yielded better results. The scale Milviscutulus mangiferae was present in very low populations. Treatment with mineral oil resulted in the highest quality fruits.

  15. MICROFUNGAL COMPOSITION IN AN ASTELIA-DONATIA CUSHION PEATLAND IN TIERRA DEL FUEGO, ARGENTINA

    Directory of Open Access Journals (Sweden)

    Noelia I. Paredes

    2014-01-01

    Full Text Available En el Hemisferio Sur las turberas almacenan grandes cantidades de carbono en el suelo. A pesar de su importancia en el ciclo global del carbono, se sabe poco acerca de los procesos de descomposición y su diversidad fúngica. El presente estudio se realizó para describir la composición de hongos filamen - tosos en dos profundidades de una turbera compacta donde las especies vegetales predominantes son Astelia (Asteliaceae y Donatia (Donatiaceae en Moat, Tierra del Fuego, Argentina. De 48 muestras procesadas, se obtuvieron 338 aislamientos. Mediante el uso de diferentes metodologías de cultivo, a través de observación microscópica y por métodos moleculares identificamos 38 especies fúngicas y 18 géneros de Ascomycetes y Zygomycetes. Los aislamientos de Ascomycetes fueron los más abundantes, con dominancia de Penicillium y Trichoderma . Se describe la composición fúngica y se comparó la diversidad y equitatividad de las especies a dos profundidades de muestreo. No se encontraron diferencias significativas entre la composición de especies, la diversidad y equitatividad. La turbera estudiada es un ecosistema que presenta alta diversidad de especies fúngicas filamentosas, algunas de ellas descritas en otras turberas en todo el mundo.

  16. Autonomous Aerial Ice Observation for Ice Defense

    Directory of Open Access Journals (Sweden)

    Joakim Haugen

    2014-10-01

    Full Text Available One of the tasks in ice defense is to gather information about the surrounding ice environment using various sensor platforms. In this manuscript we identify two monitoring tasks known in literature, namely dynamic coverage and target tracking, and motivate how these tasks are relevant in ice defense using RPAS. An optimization-based path planning concept is outlined for solving these tasks. A path planner for the target tracking problem is elaborated in more detail and a hybrid experiment, which consists of both a real fixed-wing aircraft and simulated objects, is included to show the applicability of the proposed framework.

  17. Tierras de la microcuenca potrerillo (Cauca, Colombia: Clasificación local en relación con propiedades edáficas.

    Directory of Open Access Journals (Sweden)

    Cerón Rengifo Carmen Patricia

    2003-12-01

    Full Text Available Este estudio se realizó con el objetivo de relacionar la clasificación local de tierras con propiedades físicas, químicas y biológicas del suelo. Se hicieron entrevistas a 36 agricultores de la microcuenca, Potrerillo, Cauca, Colombia, para considerar criterios culturales de clasificación local; se tomaron muestras de suelo en 8 tierras, de 0 a 5 y 0 a 20 cm, con 5 repeticiones. Se determinó color, textura, N y P disponible, C total, fracción liviana de materia orgánica (LL, PH, Ca, K, Mg y Al. Los datos se trabajaron estadísticamente a partir de análisis de varianza, prueba Duncan y análisis de clasificación de datos. La información sugiere que los agricultores diferencias las tierras a partir de la ubicación, características físicas del suelo y de categorías culturales llamadas tierra buena, mala, brava y cansada. Las tierras consideradas buenas se relacionan con colores pardos oscuros, contenidos más altos de N, C y fracción LL, mayor densidad de miriápodos en tierras con vegetación arbórea y mayor biomasa de lombrices en barbecho de la parte baja de la colina. Entre las tierras de menor calidad, disminuye N, C fracción LL y Al y aumenta el pH; en aquellas que no son utilizadas son frecuentes los colores amarillos o rojos, decrecen los valores de N, C, LL, Ph y se incrementa el Al.

  18. Arctic landfast sea ice

    Science.gov (United States)

    Konig, Christof S.

    Landfast ice is sea ice which forms and remains fixed along a coast, where it is attached either to the shore, or held between shoals or grounded icebergs. Landfast ice fundamentally modifies the momentum exchange between atmosphere and ocean, as compared to pack ice. It thus affects the heat and freshwater exchange between air and ocean and impacts on the location of ocean upwelling and downwelling zones. Further, the landfast ice edge is essential for numerous Arctic mammals and Inupiat who depend on them for their subsistence. The current generation of sea ice models is not capable of reproducing certain aspects of landfast ice formation, maintenance, and disintegration even when the spatial resolution would be sufficient to resolve such features. In my work I develop a new ice model that permits the existence of landfast sea ice even in the presence of offshore winds, as is observed in mature. Based on viscous-plastic as well as elastic-viscous-plastic ice dynamics I add tensile strength to the ice rheology and re-derive the equations as well as numerical methods to solve them. Through numerical experiments on simplified domains, the effects of those changes are demonstrated. It is found that the modifications enable landfast ice modeling, as desired. The elastic-viscous-plastic rheology leads to initial velocity fluctuations within the landfast ice that weaken the ice sheet and break it up much faster than theoretically predicted. Solving the viscous-plastic rheology using an implicit numerical method avoids those waves and comes much closer to theoretical predictions. Improvements in landfast ice modeling can only verified in comparison to observed data. I have extracted landfast sea ice data of several decades from several sources to create a landfast sea ice climatology that can be used for that purpose. Statistical analysis of the data shows several factors that significantly influence landfast ice distribution: distance from the coastline, ocean depth, as

  19. Removable cruciform for ice condenser ice basket

    International Nuclear Information System (INIS)

    Scrabis, C.M.; Mazza, G.E.; Golick, L.R.; Pomaibo, P.

    1987-01-01

    A removable cruciform for use in an ice basket having a generally cylindrical sidewall defining a central, vertical axis of the ice basket and plural, generally annular retaining rings secured to the interior of the cylindrical sidewall of the ice basket at predetermined, spaced elevations throughout the axial height of the ice basket is described comprising: a pair of brackets, each comprising a central, base portion having parallel longitudinal edges and a pair of integral legs extending at corresponding angles relative to the base portion from the perspective parallel longitudinal edges thereof; a pair of support plate assemblies secured to and extending in parallel, spaced relationship from one of the pair of brackets; a pair of slide support plates secured to the other of the pair of brackets and extending therefrom in spaced, parallel relationship; and spring means received within the housing and engaging the base portions of the brackets and applying a resilient biasing force thereto for maintaining the spaced relationship thereof

  20. Ice cream structure modification by ice-binding proteins.

    Science.gov (United States)

    Kaleda, Aleksei; Tsanev, Robert; Klesment, Tiina; Vilu, Raivo; Laos, Katrin

    2018-04-25

    Ice-binding proteins (IBPs), also known as antifreeze proteins, were added to ice cream to investigate their effect on structure and texture. Ice recrystallization inhibition was assessed in the ice cream mixes using a novel accelerated microscope assay and the ice cream microstructure was studied using an ice crystal dispersion method. It was found that adding recombinantly produced fish type III IBPs at a concentration 3 mg·L -1 made ice cream hard and crystalline with improved shape preservation during melting. Ice creams made with IBPs (both from winter rye, and type III IBP) had aggregates of ice crystals that entrapped pockets of the ice cream mixture in a rigid network. Larger individual ice crystals and no entrapment in control ice creams was observed. Based on these results a model of ice crystals aggregates formation in the presence of IBPs was proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The mirror mechanism in the parietal lobe.

    Science.gov (United States)

    Rizzolatti, Giacomo; Rozzi, Stefano

    2018-01-01

    The mirror mechanism is a basic mechanism that transforms sensory representations of others' actions into motor representations of the same actions in the brain of the observer. The mirror mechanism plays an important role in understanding actions of others. In the present chapter we discuss first the basic organization of the posterior parietal lobe in the monkey, stressing that it is best characterized as a motor scaffold, on the top of which sensory information is organized. We then describe the location of the mirror mechanism in the posterior parietal cortex of the monkey, and its functional role in areas PFG, and anterior, ventral, and lateral intraparietal areas. We will then present evidence that a similar functional organization is present in humans. We will conclude by discussing the role of the mirror mechanism in the recognition of action performed with tools. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Frontal Lobe Function in Chess Players

    Directory of Open Access Journals (Sweden)

    Vahid Nejati

    2012-05-01

    Full Text Available Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players dont have any preference in any stage of Stroop test. Chess players dont have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

  3. Frontal lobe function in chess players.

    Science.gov (United States)

    Nejati, Majid; Nejati, Vahid

    2012-01-01

    Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST) data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players don't have any preference in any stage of Stroop test. Chess players don't have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

  4. MR imaging in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Fobben, E.S.; Zimmerman, R.A.; Sperling, M.R.; Kohn, M.I.; Atlas, S.W.; Hackney, D.B.; Goldberg, H.I.; Bilaniuk, L.T.; Grossman, R.I.

    1988-01-01

    MR imaging examinations of 31 patients undergoing temporal lobe resection for refractory partial epilepsy were reviewed retrospectively for the presence of signal abnormalities as well as atrophy. High-signal abnormalities were present in only two of the described 31 patients (6.5%). Pathologically, these represented mesial temporal sclerosis and a hamartoma. Of the remaining 29 cases, 13 showed pathologically varying degrees of mesial temporal sclerosis and gliosis and 16 were pathologically normal. Atrophy, as determined by gross asymmetry, sulcal and temporal horn enlargement, and computer volume measurements, was observed in 23 of 31 patients, correlating with the clinically affected side in 20 and the contralateral side in three. In this series, in contrast to others reported, focal MR signal abnormalities were not detected in the vast majority of patients with mesial temporal sclerosis

  5. Xenomelia: a new right parietal lobe syndrome.

    Science.gov (United States)

    McGeoch, Paul D; Brang, David; Song, Tao; Lee, Roland R; Huang, Mingxiong; Ramachandran, V S

    2011-12-01

    Damage to the right parietal lobe has long been associated with various disorders of body image. The authors have recently suggested that an unusual behavioural condition in which otherwise rational individuals desire the amputation of a healthy limb might also arise from right parietal dysfunction. Four subjects who desired the amputation of healthy legs (two right, one left and one, at first, bilateral and then left only) were recruited and underwent magnetoencephalography (MEG) scans during tactile stimulation of sites above and below the desired amputation line. Regions of interest (ROIs) in each hemisphere (superior parietal lobule (SPL), inferior parietal lobule, S1, M1, insula, premotor cortex and precuneus) were defined using FreeSurfer software. Analysis of average MEG activity across the 40-140 ms post-stimulation timeframe was carried out using an unpaired t test. This revealed significantly reduced activation only in the right SPL ROI for the subjects' affected legs when compared with both subjects' unaffected legs and that of controls. The right SPL is a cortical area that appears ideally placed to unify disparate sensory inputs to create a coherent sense of having a body. The authors propose that inadequate activation of the right SPL leads to the unnatural situation in which the sufferers can feel the limb in question being touched without it actually incorporating into their body image, with a resulting desire for amputation. The authors introduce the term 'xenomelia' as a more appropriate name than apotemnophilia or body integrity identity disorder, for what appears to be an unrecognised right parietal lobe syndrome.

  6. Craniopharyngioma in the temporal lobe: a case report

    International Nuclear Information System (INIS)

    Sohn, Chul-Ho; Baik, Seung-Kug; Kim, Sang-Pyo; Kim, Il-Man; Sevick, Robert J.

    2004-01-01

    Herein, we report on an unusual case of craniopharyngioma arising in the temporal lobe with no prior history of surgery and with no connection to the craniopharyngeal duct. MR images showed cystic tumor with a small solid portion. To the best of our knowledge, this is the first case of a craniopharyngioma occurring in the temporal lobe

  7. Craniopharyngioma in the temporal lobe: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Chul-Ho; Baik, Seung-Kug; Kim, Sang-Pyo; Kim, Il-Man; Sevick, Robert J. [University of Calgary, Calgary (Canada)

    2004-03-15

    Herein, we report on an unusual case of craniopharyngioma arising in the temporal lobe with no prior history of surgery and with no connection to the craniopharyngeal duct. MR images showed cystic tumor with a small solid portion. To the best of our knowledge, this is the first case of a craniopharyngioma occurring in the temporal lobe.

  8. Craniopharyngioma in the Temporal Lobe: A Case Report

    Science.gov (United States)

    Baik, Seung Kug; Kim, Sang-Pyo; Kim, Il-Man; Sevick, Robert J.

    2004-01-01

    Herein, we report on an unusual case of craniopharyngioma arising in the temporal lobe with no prior history of surgery and with no connection to the craniopharyngeal duct. MR images showed a cystic tumor with a small solid portion. To the best of our knowledge, this is the first case of a craniopharyngioma occurring in the temporal lobe. PMID:15064562

  9. A comparative perspective on the human temporal lobe

    NARCIS (Netherlands)

    Bryant, K.L.; Preuss, T.M.; Bruner, E.; Ogihara, N.; Tanabe, H.

    2018-01-01

    The temporal lobe is a morphological specialization of primates resulting from an expansion of higher-order visual cortex that is a hallmark of the primate brain. Among primates, humans possess a temporal lobe that has significantly expanded. Several uniquely human cognitive abilities, including

  10. Surgical anatomy of the pyramidal lobe and its significance in ...

    African Journals Online (AJOL)

    In diffuse thyroid diseases, the lobes were always pathologically involved and significantly longer. Conclusion. Since the pyramidal lobe is a normal component of the thyroid gland, of varying position and size, with pathological changes in benign and malignant diseases, it should always be examined during thyroid surgery ...

  11. El escritor, las sombras y la Patria: En esta dulce tierra de Andrés Rivera The writer, the shadows and the homeland in Andrés Rivera's "La dulce tierra"

    Directory of Open Access Journals (Sweden)

    Carmen Perilli

    2007-12-01

    Full Text Available La novela En esta dulce tierra arma un simulacro histórico que se desintegra en una narración de finales múltiples. Parodia su nombre "en esta dulce tierra" ya que el circunstancial anuncia sucesos terribles que hacen estallar el adjetivo. Remite a la literatura decimonónica, en especial a los romances fundacionales como Amalia de José Mármol. La nación se imagina como espacio cerrado, clausurado por el despotismo en el asilo, la morgue, la cárcel, el sótano. Los protagonistas se mueven ilusoriamente de Sur a Norte. Si Sarmiento invoca la sombra de Facundo, Rivera evoca en Cufré otras propias sombras, dobles en tiempos y lugares otros. La narración de la historia argentina es la narración de una derrota, la de la civilización. La imagen histórica es disfórica: el mundo está enfermo, ebrio de sangre y violencia. Facundo es la sombra de la barbarie, cifra de la naturaleza americana, producto de los llanos riojanos. Cufré es la sombra de una clase "culta" que dibuja en su trayectoria una figura paradojal. Las dos son víctimas de una tierra concebida como naturaleza bárbara en un caso y de una tierra construida como patria siniestra en el otro. El Poder actúa como una segunda naturaleza que, en esta tierra, tiene el sabor de la muerte.The novel En esta dulce tierra sets up a historical pretense that disintegrates into several endings. The title is an irony, since terrible events take place in this "sweet land." It refers to the literature of the XIX century, especially to the founding romances such as that of José Mármol's Amalia. The nation is envisioned as a closed space relegated by despotism to the asylum, the morgue, the jail, the basement. The characters live an illusion moving from north to south. If Sarmiento invokes the shadow of Facundo, Rivera evokes some of his own shadows in Cufré, doubles in different times and spaces. The narration of the Argentine history is a story of defeat: civilizarion's. The historical

  12. EL SITIO HESHKAIA 35: NUEVOS DATOS SOBRE LA ARQUEOLOGÍA DE MOAT (TIERRA DEL FUEGO, ARGENTINA / Heshkaia 35 site: new data on the archaeology of Moat (Tierra del Fuego, Argentina

    Directory of Open Access Journals (Sweden)

    Atilio Francisco Zangrando

    2014-11-01

    Full Text Available arqueológicos recuperados en el sitio Heshkaia 35 (costa sur de Tierra del Fuego, Argentina. Este sitio se ubica en un ámbito costero en la sección media de la cuenca del río Moat y registra ocupaciones durante el Holoceno Tardío (ca. 800-500 AP. La diversidad tecnológica y el registro zooarqueológico señalan el desarrollo de actividades múltiples. Los artefactos líticos dominan el conjunto tecnológico. Los desechos líticos indican un fuerte énfasis hacia los estadios finales de talla, puesto de manifiesto en la baja presencia de artefactos con corteza y la elevada frecuencia de lascas de formatización y de reactivación de filos. El conjunto zooarqueológico se compone mayormente de restos óseos de guanacos. Los moluscos también habrían cumplido un rol significativo en la dieta. Restos óseos de mamíferos marinos, zorros, aves y peces están representados por frecuencias bajas. La composición artefactual y arqueofaunística estaría indicando que el aprovisionamiento de recursos se habría articulado principalmente desde el ámbito costero y no necesariamente en el mar. Se discuten las implicaciones de esta evidencia para las pautas conductuales de cazadores-recolectores en la costa sur de Tierra del Fuego. Palabras Clave: Arqueología de costas, Cazadores-recolectores, Tierra del Fuego, Holoceno Tardío   Abstract This paper presents and discusses the archaeological evidence from Heshkaia 35 site (southern coast of Tierra del Fuego, Argentina. This site is located in a coastal setting in the middle section of the Moat River Basin and records occupations during the Late Holocene (ca. 800-500 BP. Technological diversity and the zooarchaeological record point to the development of multiple activities. Lithic artifacts dominate the technological assemblage. Lithic debitage indicates a strong emphasis towards final stages of reduction, shown by the lower occurrence of artifacts with cortex and the high frequency resharpening

  13. Mirror focus in a patient with intractable occipital lobe epilepsy.

    Science.gov (United States)

    Kim, Jiyoung; Shin, Hae Kyung; Hwang, Kyoung Jin; Choi, Su Jung; Joo, Eun Yeon; Hong, Seung Bong; Hong, Seung Chul; Seo, Dae-Won

    2014-06-01

    Mirror focus is one of the evidence of progression in epilepsy, and also has practical points for curative resective epilepsy surgery. The mirror foci are related to the kindling phenomena that occur through interhemispheric callosal or commissural connections. A mirror focus means the secondary epileptogenic foci develop in the contralateral hemispheric homotopic area. Thus mirror foci are mostly reported in patients with temporal or frontal lobe epilepsy, but not in occipital lobe epilepsy. We have observed occipital lobe epilepsy with mirror focus. Before epilepsy surgery, the subject's seizure onset zone was observed in the left occipital area by ictal studies. Her seizures abated for 10 months after the resection of left occipital epileptogenic focus, but recurred then. The recurred seizures were originated from the right occipital area which was in the homotopic contralateral area. This case can be an evidence that occipital lobe epilepsy may have mirror foci, even though each occipital lobe has any direct interhemispheric callosal connections between them.

  14. Supplementary CT temporal lobe cuts confer no worthwhile benefit

    Energy Technology Data Exchange (ETDEWEB)

    Straiton, J A; Macpherson, P; Teasdale, E M [Institute of Neurological Sciences, Glasgow (UK). Dept. of Neuroradiology

    1991-02-01

    The value of angled temporal lobe cuts as a supplement to conventional head computed tomography (CT) has been assessed by comparing the diagnostic yield of standard axial and specific temporal lobe images (TLCT) in 62 patients with temporal lobe epilepsy and 87 with Alzheimer-type senile dementia. Fewer than one patient in six had structural abnormality in the temporal lobe most readily demonstrated by axial CT. Five patients with epilepsy and ten with dementia had changes demonstrated only by TLCT, reported on by one or other of a pair of observers. However such changes were of dubious clinical relevance, or arose as a result of artefact. In one patient with epilepsy and underlying neoplasm, axial CT was positive and TLCT false-negative. The routine addition of temporal lobe cuts to a conventional axial examination confers no added benefit to justify the prolonged examination time and increased radiation dose to the lens of the eye. (orig.).

  15. Supplementary CT temporal lobe cuts confer no worthwhile benefit

    International Nuclear Information System (INIS)

    Straiton, J.A.; Macpherson, P.; Teasdale, E.M.

    1991-01-01

    The value of angled temporal lobe cuts as a supplement to conventional head computed tomography (CT) has been assessed by comparing the diagnostic yield of standard axial and specific temporal lobe images (TLCT) in 62 patients with temporal lobe epilepsy and 87 with Alzheimer-type senile dementia. Fewer than one patient in six had structural abnormality in the temporal lobe most readily demonstrated by axial CT. Five patients with epilepsy and ten with dementia had changes demonstrated only by TLCT, reported on by one or other of a pair of observers. However such changes were of dubious clinical relevance, or arose as a result of artefact. In one patient with epilepsy and underlying neoplasm, axial CT was positive and TLCT false-negative. The routine addition of temporal lobe cuts to a conventional axial examination confers no added benefit to justify the prolonged examination time and increased radiation dose to the lens of the eye. (orig.)

  16. An Efficient Approach for Identifying Stable Lobes with Discretization Method

    Directory of Open Access Journals (Sweden)

    Baohai Wu

    2013-01-01

    Full Text Available This paper presents a new approach for quick identification of chatter stability lobes with discretization method. Firstly, three different kinds of stability regions are defined: absolute stable region, valid region, and invalid region. Secondly, while identifying the chatter stability lobes, three different regions within the chatter stability lobes are identified with relatively large time intervals. Thirdly, stability boundary within the valid regions is finely calculated to get exact chatter stability lobes. The proposed method only needs to test a small portion of spindle speed and cutting depth set; about 89% computation time is savedcompared with full discretization method. It spends only about10 minutes to get exact chatter stability lobes. Since, based on discretization method, the proposed method can be used for different immersion cutting including low immersion cutting process, the proposed method can be directly implemented in the workshop to promote machining parameters selection efficiency.

  17. Aircraft Icing Handbook. (Update)

    Science.gov (United States)

    1993-01-01

    Report 1946-1947, U. S. Air Material Command Tech. Rept. 5676. Findeisen , W., *Meteorological Commentary of D (air) 1209, Icing,* Germany, Reichsamt fur...Wetterdienst, Forschungs-und Krfahrungsberichte, Ser. a, No. 29, 1943. Findeisen , W., *Meteorological-Physical Limitations of Icing on the Atmosphere...Apparatus for Measurement,’ Harvard - Mt. Washington Icing Research Report 1946-1947, U. S. Air Material Command Tech. Rept. 5676.. Findeisen , W., "The

  18. La ganadería lanar en Madrid y su tierra durante la Edad Media

    Directory of Open Access Journals (Sweden)

    Tomás Puñal Fernández

    1998-01-01

    Full Text Available El estudio de la ganadería en general y ovina en particular ofrece un campo muy generoso de investigación porque permite conocer muchas de las estructuras socioeconómicas regionales y locales de un país o territorio. En el caso de Madrid dicho estudio es importante por cuanto en el conjunto de las labores agropecuarias del concejo, las ganaderas fueron las que mejor marcaron su desarrollo económico. La tierra madrileña es tierra de ganado, sobre todo lanar, y ello fue el punto de referencia de diversas actividades económicas que iban desde el abastecimiento de carne para la alimentación hasta la obtención de materia prima, lana y pieles, para las industrias textil y del cuero. Para tener una visión más amplia e interdisciplinar el presente estudio se ha hecho desde una doble perspectiva económica y social. Desde la ganadería estante y local a la trashumante, con especial mención a la Mesta y toda su problemática, así como los aspectos cuantitativos derivados del número de ovejas y el tamaño y tipo de los rebaños y sus aspectos fiscales concomitantes. En relación a ello toda la infraestructura de pastos y cañadas. Los aspectos sociales se refieren a los propietarios de ovejas como una oligarquía rural de labradores enriquecidos, así como a los trabajadores del ganado, es decir los pastores, sus contratos, salarios y condiciones de vida. En conjunto el panorama que se ofrece es muy significativo y permite acercarnos un poco más a la realidad socioeconómica del Madrid medieval.The study of the livestock in general and sheep in particular, offers a huge field to research as it allows to know many of the local and regional socioeconomíc structures of a city or country. In the case of Madrid, that study is important because the sheep livestock is, among the rest of the agricultural activities, the main one for its contribution to the economic development. Madrid is a livestock área, mainly for sheep, as the point of

  19. The cognitive profile of occipital lobe epilepsy and the selective association of left temporal lobe hypometabolism with verbal memory impairment.

    Science.gov (United States)

    Knopman, Alex A; Wong, Chong H; Stevenson, Richard J; Homewood, Judi; Mohamed, Armin; Somerville, Ernest; Eberl, Stefan; Wen, Lingfeng; Fulham, Michael; Bleasel, Andrew F

    2014-08-01

    We investigated the cognitive profile of structural occipital lobe epilepsy (OLE) and whether verbal memory impairment is selectively associated with left temporal lobe hypometabolism on [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET). Nine patients with OLE, ages 8-29 years, completed presurgical neuropsychological assessment. Composite measures were calculated for intelligence quotient (IQ), speed, attention, verbal memory, nonverbal memory, and executive functioning. In addition, the Wisconsin Card Sorting Test (WCST) was used as a specific measure of frontal lobe functioning. Presurgical FDG-PET was analyzed with statistical parametric mapping in 8 patients relative to 16 healthy volunteers. Mild impairments were evident for IQ, speed, attention, and executive functioning. Four patients demonstrated moderate or severe verbal memory impairment. Temporal lobe hypometabolism was found in seven of eight patients. Poorer verbal memory was associated with left temporal lobe hypometabolism (p = 0.002), which was stronger (p = 0.03 and p = 0.005, respectively) than the association of left temporal lobe hypometabolism with executive functioning or with performance on the WCST. OLE is associated with widespread cognitive comorbidity, suggesting cortical dysfunction beyond the occipital lobe. Verbal memory impairment is selectively associated with left temporal lobe hypometabolism in OLE, supporting a link between neuropsychological dysfunction and remote hypometabolism in focal epilepsy. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

  20. Safe Loads on Ice Sheets (Ice Engineering. Number 13)

    National Research Council Canada - National Science Library

    Haynes, F. D; Carey, Kevin L; Cattabriga, Gioia

    1996-01-01

    Every winter, ice sheets that grow on lakes and rivers in northern states are used for ice roads, ice bridges, construction platforms, airstrips, and recreational activities, It becomes very important...

  1. PET imaging in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Semah, F.

    2006-01-01

    The research projects on epilepsy addressed two main issues: the pathophysiology of the inter-ictal hypo-metabolism in temporal lobe epilepsy and the role of the basal ganglia in the control of seizure. Our research projects focused primarily on temporal lobe epilepsy: The pathophysiology of inter-ictal hypo-metabolism and its correlation with the epileptogenic network was investigated in patients with mesial temporal lobe epilepsy. Inter-ictal hypo-metabolism is commonly found in mesio-temporal lobe epilepsy (MTLE) but its pathophysiology remains incompletely understood. We hypothesized that metabolic changes reflect the preferential networks involved in ictal discharges. We analyzed the topography of inter-ictal hypo-metabolism according to electro-clinical patterns in 50 patients with unilateral hippocampal sclerosis (HS) and consistent features of MTLE. Based on electro-clinical correlations we identified 4 groups:1) mesial group characterized by mesial seizure onset without evidence of early spread beyond the temporal lobe; 2) anterior mesio-lateral group (AML) with early anterior spread, involving the anterior lateral temporal cortex and insulo-fronto-opercular areas; 3) widespread mesio-lateral group (WML) with widespread spread, involving both anterior and posterior lateral temporal and peri-sylvian areas; 4) bi-temporal group (BT) with early contralateral temporal spread. Results of FDG-PET imaging in each group were compared to control subjects using statistical parametric mapping software (SPM99). MRI data and surgical outcome in each group were compared to metabolic findings. Hypo-metabolism was limited to the hippocampal gyrus, the temporal pole and the insula in the mesial group. Gradual involvement of the lateral temporal cortex, the insula and the peri-sylvian areas was observed in the AML and WML groups. The BT group differed from the others by mild bi-temporal involvement, bilateral insular hypo-metabolism and longer epilepsy duration. MRI

  2. PET imaging in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Semah, F. [Service Hospitalier Frederic Joliot, DSV-CEA, 91 Orsay (France)

    2006-07-01

    The research projects on epilepsy addressed two main issues: the pathophysiology of the inter-ictal hypo-metabolism in temporal lobe epilepsy and the role of the basal ganglia in the control of seizure. Our research projects focused primarily on temporal lobe epilepsy: The pathophysiology of inter-ictal hypo-metabolism and its correlation with the epileptogenic network was investigated in patients with mesial temporal lobe epilepsy. Inter-ictal hypo-metabolism is commonly found in mesio-temporal lobe epilepsy (MTLE) but its pathophysiology remains incompletely understood. We hypothesized that metabolic changes reflect the preferential networks involved in ictal discharges. We analyzed the topography of inter-ictal hypo-metabolism according to electro-clinical patterns in 50 patients with unilateral hippocampal sclerosis (HS) and consistent features of MTLE. Based on electro-clinical correlations we identified 4 groups:1) mesial group characterized by mesial seizure onset without evidence of early spread beyond the temporal lobe; 2) anterior mesio-lateral group (AML) with early anterior spread, involving the anterior lateral temporal cortex and insulo-fronto-opercular areas; 3) widespread mesio-lateral group (WML) with widespread spread, involving both anterior and posterior lateral temporal and peri-sylvian areas; 4) bi-temporal group (BT) with early contralateral temporal spread. Results of FDG-PET imaging in each group were compared to control subjects using statistical parametric mapping software (SPM99). MRI data and surgical outcome in each group were compared to metabolic findings. Hypo-metabolism was limited to the hippocampal gyrus, the temporal pole and the insula in the mesial group. Gradual involvement of the lateral temporal cortex, the insula and the peri-sylvian areas was observed in the AML and WML groups. The BT group differed from the others by mild bi-temporal involvement, bilateral insular hypo-metabolism and longer epilepsy duration. MRI

  3. Mires and mire types of Peninsula Mitre, Tierra del Fuego, Argentina

    Directory of Open Access Journals (Sweden)

    A. Grootjans

    2014-01-01

    Full Text Available In 2007, a field visit by members of the International Mire Conservation Group (IMCG to the Atlantic coast of Peninsula Mitre (the easternmost part of Isla Grande de Tierra del Fuego, Argentina gathered information on mire diversity in this remote wild area with largely pristine mires. Our expedition showed that Peninsula Mitre hosts a wide variety of habitats across two exciting ecological gradients: (i a regional west–east gradient from Sphagnum magellanicum dominated mires in the west to Astelia pumila dominated mires in the east; and (ii a gradient from extremely acid to extremely carbonate rich mire types induced by local bedrock. The large variety of hydromorphological mire types comprises raised bogs, blanket bogs, sloping fens, string fens, flat fens and calcareous spring fens. In the Atlantic coastal area, the abundance of Sphagnum magellanicum in the ombrogenic systems decreases conspicuously from west to east with the species being almost absent in the east. However, the fossil record shows thick layers of Sphagnum peat close beneath mire surfaces everywhere, indicating that substantial hydrological and ecological changes have taken place in the recent past. We observed large scale erosion in the mires along the Atlantic coast. Locally, well-developed fen systems are present, including calcareous spring fens with active travertine (tufa deposition. The regional vegetation can be regarded as a parallel to that of boreal oceanic regions in the northern hemisphere. The mires and peatlands of the peninsula are of global significance. They are impressive, peculiar, extensive and largely pristine mires in a globally very rare climatic and biogeographical context embedded in a landscape with significant natural dynamics. The damaging impact of free-roaming cattle on the mires and upland vegetation is, however, conspicuous and needs urgent attention. Peninsula Mitre deserves the highest possible protection, e.g. as a provincial protected

  4. Modeling the Thickness of Perennial Ice Covers on Stratified Lakes of the Taylor Valley, Antarctica

    Science.gov (United States)

    Obryk, M. K.; Doran, P. T.; Hicks, J. A.; McKay, C. P.; Priscu, J. C.

    2016-01-01

    A one-dimensional ice cover model was developed to predict and constrain drivers of long term ice thickness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface radiative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 years (between 1996 and 2012) of ice thickness changes for west lobe of Lake Bonney (average ice thickness = 3.53 m; RMSE = 0.09 m, n = 118) and Lake Fryxell (average ice thickness = 4.22 m; RMSE = 0.21 m, n = 128). Long-term ice thickness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of lakes exceeding a liquid water column depth of 20 m can either impede or facilitate ice thickness change depending on the predominant climatic trend (temperature cooling or warming). As such, shallow (< 20 m deep water columns) perennially ice-covered lakes without deep temperature maxima are more sensitive indicators of climate change. The long-term ice thickness trends are a result of surface energy flux and heat flux from the deep temperature maximum in the water column, the latter of which results from absorbed solar radiation.

  5. Geoprocesamiento aplicado al analisis del uso de la tierra en el municipio de San Pedro de Ycuamandyyú , Paraguay

    Directory of Open Access Journals (Sweden)

    Oscar Agustín Figueredo Torres

    2002-01-01

    Full Text Available El municipio de San Pedro de Ycuamandyyú está ubicado en el noroeste de la región oriental del Paraguay. Los objetivos de este trabajo constituyen la elaboración y el análisis del mapa del uso de la tierra para la planificación de actividades forestales en la zona, para los cuales se utilizaron técnicas de cartografía, sensores remotos y (SIG Sistemas de Informaciones Geográficas, que posibilitaron el análisis de informaciones provenientes de imágenes satelitales LANDSAT TM 5, de cartas topográficas y de (GPS Sistema de Posicionamiento Global, que permitió el procesamiento de datos en el programa Idrisi 2.0 para la confección de un mapa que posibilitó el análisis sobre la situación del uso de la tierra en el municipio. Se distinguió categorías predominantes como praderas altas o campos naturales, uso agropecuario y praderas bajas o bañados, siendo la cobertura forestal con valor inferior al 25%. Se concluyó que el municipio presenta bastantes áreas de campos naturales y uso agropecuario que podrían utilizarse para actividades de reforestación, sea con especies nativas o exóticas de rápido crecimiento con la finalidad de obtener valores de cobertura forestal en equilibrio con las demás categorías de uso de la tierra.

  6. Geoprocesamiento aplicado al analisis del uso de la tierra en el municipio de San Pedro de Ycuamandyyú, Paraguay.

    Directory of Open Access Journals (Sweden)

    Oscar Agustín Torres Figueredo

    2010-08-01

    Full Text Available El municipio de San Pedro de Ycuamandyyú está ubicado en el noroeste de la región oriental del Paraguay. Los objetivos de este trabajo constituyen la elaboración y el análisis del mapa del uso de la tierra para la planificación de actividades forestales en la zona, para los cuales se utilizaron técnicas de cartografía, sensores remotos y (SIG Sistemas de Informaciones Geográficas, que posibilitaron el análisis de informaciones provenientes de imágenes satelitales LANDSAT TM 5, de cartas topográficas y de (GPS Sistema de Posicionamiento Global, que permitió el procesamiento de datos en el programa Idrisi 2.0 para la confección de un mapa que posibilitó el análisis sobre la situación del uso de la tierra en el municipio. Se distinguió categorías predominantes como praderas altas o campos naturales, uso agropecuario y praderas bajas o bañados, siendo la cobertura forestal con valor inferior al 25%. Se concluyó que el municipio presenta bastantes áreas de campos naturales y uso agropecuario que podrían utilizarse para actividades de reforestación, sea con especies nativas o exóticas de rápido crecimiento con la finalidad de obtener valores de cobertura forestal en equilibrio con las demás categorías de uso de la tierra.

  7. GEOPROCESAMIENTO APLICADO AL ANALISIS DEL USO DE LA TIERRA EN EL MUNICIPIO DE SAN PEDRO DE YCUAMANDYYÚ, PARAGUAY

    Directory of Open Access Journals (Sweden)

    Oscar Agustín Torres Figueredo

    2002-10-01

    Full Text Available El municipio de San Pedro de Ycuamandyyú está ubicado en el noroeste de la región oriental del Paraguay. Los objetivos de este trabajo constituyen la elaboración y el análisis del mapa del uso de la tierra para la planificación de actividades forestales en la zona, para los cuales se utilizaron técnicas de cartografía, sensores remotos y (SIG Sistemas de Informaciones Geográficas, que posibilitaron el análisis de informaciones provenientes de imágenes satelitales LANDSAT TM 5, de cartas topográficas y de (GPS Sistema de Posicionamiento Global, que permitió el procesamiento de datos en el programa Idrisi 2.0 para la confección de un mapa que posibilitó el análisis sobre la situación del uso de la tierra en el municipio. Se distinguió categorías predominantes como praderas altas o campos naturales, uso agropecuario y praderas bajas o bañados, siendo la cobertura forestal con valor inferior al 25%. Se concluyó que el municipio presenta bastantes áreas de campos naturales y uso agropecuario que podrían utilizarse para actividades de reforestación, sea con especies nativas o exóticas de rápido crecimiento con la finalidad de obtener valores de cobertura forestal en equilibrio con las demás categorías de uso de la tierra.

  8. Ice and ocean velocity in the Arctic marginal ice zone: Ice roughness and momentum transfer

    Directory of Open Access Journals (Sweden)

    Sylvia T. Cole

    2017-09-01

    Full Text Available The interplay between sea ice concentration, sea ice roughness, ocean stratification, and momentum transfer to the ice and ocean is subject to seasonal and decadal variations that are crucial to understanding the present and future air-ice-ocean system in the Arctic. In this study, continuous observations in the Canada Basin from March through December 2014 were used to investigate spatial differences and temporal changes in under-ice roughness and momentum transfer as the ice cover evolved seasonally. Observations of wind, ice, and ocean properties from four clusters of drifting instrument systems were complemented by direct drill-hole measurements and instrumented overhead flights by NASA operation IceBridge in March, as well as satellite remote sensing imagery about the instrument clusters. Spatially, directly estimated ice-ocean drag coefficients varied by a factor of three with rougher ice associated with smaller multi-year ice floe sizes embedded within the first-year-ice/multi-year-ice conglomerate. Temporal differences in the ice-ocean drag coefficient of 20–30% were observed prior to the mixed layer shoaling in summer and were associated with ice concentrations falling below 100%. The ice-ocean drag coefficient parameterization was found to be invalid in September with low ice concentrations and small ice floe sizes. Maximum momentum transfer to the ice occurred for moderate ice concentrations, and transfer to the ocean for the lowest ice concentrations and shallowest stratification. Wind work and ocean work on the ice were the dominant terms in the kinetic energy budget of the ice throughout the melt season, consistent with free drift conditions. Overall, ice topography, ice concentration, and the shallow summer mixed layer all influenced mixed layer currents and the transfer of momentum within the air-ice-ocean system. The observed changes in momentum transfer show that care must be taken to determine appropriate parameterizations

  9. El acaparamiento de tierras como proceso dinámico. Las estrategias de los actores en contextos de estancamiento económico

    Directory of Open Access Journals (Sweden)

    Carla Gras

    2017-01-01

    Full Text Available Este artículo pretende contribuir a la comprensión de los procesos de acaparamiento de tierras. A partir de un análisis realizado en el norte de Córdoba (Argentina, se sugiere que dicho fenómeno: (a no es lineal, uniforme ni se incrementa de manera sostenida en el tiempo; y (b no se limita a la concentración de tierras sino que integra recursos estratégicos (financieros, tecnológicos, gerenciales que convergen en el objetivo más general de acaparamiento de capital. Analizamos una dinámica específica, la “ralentización” o disminución en la cantidad de tierra controlada por las empresas, bajo la hipótesis que ella no constituye necesariamente una retracción del acaparamiento.

  10. Modelos del planeta Tierra en escolares rurales de Chile / Planet Earth models about students in rural schools from Chile

    Directory of Open Access Journals (Sweden)

    Paula Alonqueo Boudon

    2015-12-01

    Full Text Available RESUMEN El presente estudio tuvo como objetivo identificar los modelos del planeta Tierra en escolares mapuches y no mapuches de procedencia rural. Los participantes fueron 40 escolares distribuidos en dos grupos de edad, quienes respondieron a una tarea cognitiva que indaga la representación de la forma del planeta Tierra. En base al grado de acuerdo con la representación científica, cada participante fue categorizado en uno de cuatro modelos del planeta Tierra. El modelo 4, concordante con el conocimiento científico, no fue observado, pues la mayoría de los participantes se concentra en el modelo 3 en el que coexisten conocimientos previos con algunos elementos científicos. En los niños no mapuches se aprecia que el modelo del planeta Tierra se ajusta a los significados científicos a medida que aumenta el conocimiento escolar. Por el contrario, en los niños mapuches no se observa esta tendencia. Se discute el papel de la cultura y la enseñanza en el aprendizaje del modelo científico del planeta. ABSTRACT The aim of this study was to identify planet Earth models in mapuches and non mapuches students of rural origin. The participants were 40 students divided into two age groups who responded to a cognitive task which explores the representation of the shape of the planet Earth. Based on the degree of agreement with the scientific representation, each participant was categorized into one of four models of planet Earth. Model 4, consistent with the scientific knowledge was not observed because the majority of the participants were concentrated in Model 3. In non mapuche children, it is observed that the model of the planet Earth is adjusted to the scientific meaning in accordance with the increase of school knowledge. On the other hand, this trend is not observed in mapuche children. The role of culture and teaching is discussed in the learning of planet scientific model.

  11. Género, propiedad y empoderamiento: tierra, Estado y mercado en América Latina [Reseña

    OpenAIRE

    García Núñez, Luis Fernando; León, Magdalena; Deere, Carmen Diana

    2001-01-01

    Es un texto de una gran importancia para el momento actual. Un documento que trabaja el problema de género desde otras perspectivas. Integra el conflicto alrededor de las fronteras de lo social, lo político, lo cultural y lo económico. "Desde nuestra investigación inicial en los años setenta y ochenta se habían realizado relativamente pocos estudios sobre género y derecho a la tierra, y casi no se había prestado atención a las implicaciones de género de la contrarreforma agraria neoliberal". ...

  12. Estudio de la estructura cortical en la Isla de Tierra del Fuego a partir de datos sismológicos

    OpenAIRE

    Buffoni, C.; Schimmel, Martin; Sabbione, N.C.; Rosa, M.L.

    2012-01-01

    La Isla de Tierra del Fuego (TdF) se encuentra ubicada en el extremo sur de la Cuenca de Magallanes, donde el borde transformante entre la Placa de Scotia y la Sudamericana define el Sistema de Fallas Magallanes-Fagnano (MFS), cuya falla principal tiene un movimiento sinestral. Con el fin de obtener información de la corteza, se realizó un análisis de funciones receptoras (FR) a partir de datos registrados en cinco estaciones sismológicas instaladas en la Isla. Una FR es el resultado de un pr...

  13. Tierra y negocios en Salta a fines del siglo XIX y principios del XX. Estudio de casos

    OpenAIRE

    del Valle Michel, Azucena; Parrón, Mario Gustavo; Corregidor, Blanca Esther

    2017-01-01

    El trabajo analiza las estrategias desarrolladas por Vicente Arquati y Paulino Echazú en diferentes espacios socioeconómicos de la provincia de Salta, entre fines del siglo XIX y principios del XX. Las mismas, posibilitaron la concentración de tierras, la comercialización de productos y otras actividades lucrativas. Sobre estas cuestiones se plantean interrogantes para identificar los factores explicativos de la imposibilidad de esos sujetos de mantener sus logros económicos, a pesar de haber...

  14. Difference fractal surfaces poured earth floors Tamaulipas / Diferencia fractal en superficies de tierra vertida con suelo de Tamaulipas

    Directory of Open Access Journals (Sweden)

    Edgardo Jonathan Suárez Dominguez

    2013-09-01

    Full Text Available Poured earth is a sustainable construction and economically feasible technique to develop in Tamaulipas, by the materials availability and traditional manufacturing procedures uses. There are several variables to be considered in these elements for their properties, among them it can be found roughness and porosity analysis which are important because they are related to material mechanical resistance and durability. This study aimed to characterize solid surfaces using fractal dimension to know its uniformity and porosity, compared with a concrete surface. Solids were obtained from poured earth of two combinations of soils stabilized with cement from the state of Tamaulipas. We found that a surface of a sample, obtained with ground, is more uniform than poured concrete surface, and that fractal dimension is higher while porosity increases; results suggest that this is because of the presence of clay in the poured earth mixtures. La tierra vertida es una técnica constructiva sustentable y económicamente viable para desarrollarse en Tamaulipas, por la disponibilidad de materiales y procedimientos de fabricación similares a los tradicionales. Son diversas las variables que deben estudiarse en estos elementos para conocer sus propiedades, entre las que se encuentran la rugosidad y la porosidad, las cuales son importantes debido a su estrecha relación con la resistencia mecánica y durabilidad del material estudiado. El presente trabajo tuvo por objetivo caracterizar superficies sólidas a partir de la dimensión fractal para conocer su uniformidad y porosidad, comparándola con una superficie de concreto. Los sólidos fueron obtenidos a partir de tierra vertida conformada de dos combinaciones de suelos estabilizadas con cemento provenientes del estado de Tamaulipas. Se encontró que una superficie de tierra vertida es menos irregular que una superficie de concreto además de tener una menor porosidad reflejada en una menor dimensión fractal

  15. Tenencia de la tierra y desarrollo rural sostenible: algunos puntos para la reflexión en el caso venezolano.

    OpenAIRE

    Delahaye, Olivier

    2007-01-01

    1.- Artículos Tenencia de la tierra y desarrollo rural sostenible: algunos puntos para la reflexión en el caso venezolano. Land tenure and sustained rural development: points for reflecting on the Venezuelan case. Tenure de la terre et développement rural durable : quelques points pour la réflexion dans le cas du Venezuela. Delahaye, Olivier Paradigmas del mercado financiero rural en países en desarrollo. Paradigms in the rural financial markets in developing countries. ...

  16. Acceso a la tierra de los ex huasipungueros en la hacienda "Carpuela", en el valle del Chota.

    OpenAIRE

    Villa Zura, Marco Patricio

    2015-01-01

    El propo?sito del presente estudio de investigacio?n es abordar como fue el acceso a la tierra de los ex huasipungueros en la hacienda Carpuela en el Valle del Chota, parroquia Ambuqui?, canto?n Ibarra, Provincia de Imbabura, quienes fortalecieron la organizacio?n comunitaria, apoya?ndose en la Ley de Reforma Agraria, ejecutada por el Instituto Ecuatoriano de Reforma Agraria y Colonizacio?n de 1964 y la de 1973 que continuo. Adema?s autores teo?ricos reflejan la historia de los jesuitas qu...

  17. Cultivable microflora and endo mycorrhizas obtained in litter forest (Paramo Guerrero - Finca Puente de Tierra) Zipaquira, Colombia

    International Nuclear Information System (INIS)

    Bernal, Eleonora; Celis, Sebastian; Galindez, Ximena; Moratto, Claudia; Sanchez, Jimena; Garcia, Daniel

    2006-01-01

    The count of cultivable microorganisms (bacteria and fungi), cellulolytic microorganisms and endo mycorrhizas present in litter forest (property Puente de Tierra) in the Guerrero's moor, Colombia was made. The most frequently isolated microorganisms belonged to the staphylococcus, bacillus, pseudomonas, micrococcus, penicillium and rhodotorulagenus and cladosporium sp., which is a cellulolytic microorganism, was isolated in carboxymethyl cellulose agar. In addition eight morphotypes of endomycorrhizas were found, species of glomus and acaulospora predominated among them. This study contributes with the knowledge of the cultivable microorganisms of litter that have been little explored in moor ecosystems

  18. Forestaciones en tierras agrarias de la Región de Murcia : cambios medioambientales y paisajísticos

    OpenAIRE

    González Botía, Miguel Ángel

    2017-01-01

    El objetivo principal de esta tesis ha sido el estudio de las consecuencias derivadas de las forestaciones de tierras agrarias abandonadas en la Región de Murcia (FOTARM), considerada una medida agroambiental de la PAC, que pretende paliar los graves problemas de erosión, degradación y desertificación, derivados de dicho abandono. Primeramente se ha realizado un minucioso análisis de las forestaciones, que se llevaron a cabo en dos periodos: el primero (y principal) de 1994 a 1999, (llegando ...

  19. Bacterial Ice Crystal Controlling Proteins

    Science.gov (United States)

    Lorv, Janet S. H.; Rose, David R.; Glick, Bernard R.

    2014-01-01

    Across the world, many ice active bacteria utilize ice crystal controlling proteins for aid in freezing tolerance at subzero temperatures. Ice crystal controlling proteins include both antifreeze and ice nucleation proteins. Antifreeze proteins minimize freezing damage by inhibiting growth of large ice crystals, while ice nucleation proteins induce formation of embryonic ice crystals. Although both protein classes have differing functions, these proteins use the same ice binding mechanisms. Rather than direct binding, it is probable that these protein classes create an ice surface prior to ice crystal surface adsorption. Function is differentiated by molecular size of the protein. This paper reviews the similar and different aspects of bacterial antifreeze and ice nucleation proteins, the role of these proteins in freezing tolerance, prevalence of these proteins in psychrophiles, and current mechanisms of protein-ice interactions. PMID:24579057

  20. [Mirror movement due to the medial frontal lobe lesion].

    Science.gov (United States)

    Takahashi, N; Kawamura, M; Hirayama, K

    1995-01-01

    We reported a case with acquired mirror movement in upper limbs due to the lesion of right medial frontal lobe including supplementary motor area, and also discussed a possible mechanism underlying it. A 59-year-old right-handed woman developed left hemiparesis caused by cerebral hemorrhage in the right frontoparietal lobe, on April 5, 1981. She had right hemiparesis and right hemianopsia due to cerebral hemorrhage in the left parieto-occipital lobe, 13 days later. As the patient was recovering from paresis, mirror movement appeared on upper limbs. The features of the mirror movement of this case are summarized as follows: (1) it appeared when using both proximal and distal region of upper limbs; (2) it appeared on left upper limb when the patient intended to move right upper limb or on right upper limb when intended to move left upper limb, while it appeared predominantly in the former; and (3) it was more remarkably found in habitual movement using gesture and pantomimic movement for the use of objects, and it was found in lower degree when actual object was used or when the patient tried to imitate the gesture of the examiner. The lesions in MRI were found in medial region of right frontal lobe (supplementary motor area, medial region of motor area, and cingulate gyrus), right medial parietal lobe, posterior region of right occipital lobe, and medial regions of left parietal and occipital lobes. There was no apparent abnormality in corpus callosum.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Cambio del uso de la tierra y pérdida de la cobertura boscosa, comunidades agrarias Sechina, La Ensenada y Cerro San Gil, Izabal Guatemala

    Directory of Open Access Journals (Sweden)

    Eddi Alejandro Vanegas Chacón

    2016-07-01

    Full Text Available En Guatemala, pocas temáticas son abordadas con tanta pasión como el acceso a la tierra y sus relaciones de productividad. Ante el juicio histórico y la evidencia de las estadísticas se deslumbra que las políticas agrarias de los últimos cincuenta años, si bien mitigaron la pobreza en el agro rural conllevaron con ellas daños ambientales irreversibles y deudas agrarias millonarias. Se estudió la dinámica del cambio de uso de la tierra y la pérdida de la cobertura boscosa en las comunidades agrarias beneficiadas por la Ley de Transformación Agraria, Sechina, La Ensenada y Cerro San Gil ubicadas en el departamento de Izabal. Se utilizó fotointerpretación y se realizaron estudios semidetallados de la intensidad de la tierra para el periodo 1958 a 2010. Se concluyó que bajo las premisas de “mejora a la tierra” de la Ley de Transformación Agraria ocurrió cambio de uso y cobertura de la tierra, de forestal a agropecuaria, en las comunidades agrarias Sechina 42%, La Ensenada 46,2% y Cerro San Gil 48,6%, donde se promovieron sistemas de aprovechamiento agrícola que conllevaron al sobre-uso de las tierras en 42%, 78% y 30%, respectivamente. Esto sugiere, que la adquisición de la tierra no es el fin, más bien es el medio, para promover desarrollo rural sostenible, a través de acompañamiento técnico agropecuario, monitoreo y evaluación tanto económica como ambiental.

  2. Atypical handedness in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Doležalová, Irena; Schachter, Steven; Chrastina, Jan; Hemza, Jan; Hermanová, Markéta; Rektor, Ivan; Pažourková, Marta; Brázdil, Milan

    2017-07-01

    The main aim of our study was to investigate the handedness of patients with mesial temporal lobe epilepsy (MTLE). We also sought to identify clinical variables that correlated with left-handedness in this population. Handedness (laterality quotient) was assessed in 73 consecutive patients with MTLE associated with unilateral hippocampal sclerosis (HS) using the Edinburgh Handedness Inventory. Associations between right- and left-handedness and clinical variables were investigated. We found that 54 (74.0%) patients were right-handed, and 19 (26%) patients were left-handed. There were 15 (36.6%) left-handed patients with left-sided seizure onset compared to 4 (12.5%) left-handed patients with right-sided seizure onset (p=0.030). Among patients with left-sided MTLE, age at epilepsy onset was significantly correlated with handedness (8years of age [median; min-max 0.5-17] in left-handers versus 15years of age [median; min-max 3-30] in right-handers (p<0.001). Left-sided MTLE is associated with atypical handedness, especially when seizure onset occurs during an active period of brain development, suggesting a bi-hemispheric neuroplastic process for establishing motor dominance in patients with early-onset left-sided MTLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Episodic reinstatement in the medial temporal lobe.

    Science.gov (United States)

    Staresina, Bernhard P; Henson, Richard N A; Kriegeskorte, Nikolaus; Alink, Arjen

    2012-12-12

    The essence of episodic memory is our ability to reexperience past events in great detail, even in the absence of external stimulus cues. Does the phenomenological reinstatement of past experiences go along with reinstating unique neural representations in the brain? And if so, how is this accomplished by the medial temporal lobe (MTL), a brain region intimately linked to episodic memory? Computational models suggest that such reinstatement (also termed "pattern completion") in cortical regions is mediated by the hippocampus, a key region of the MTL. Although recent functional magnetic resonance imaging studies demonstrated reinstatement of coarse item properties like stimulus category or task context across different brain regions, it has not yet been shown whether reinstatement can be observed at the level of individual, discrete events-arguably the defining feature of episodic memory-nor whether MTL structures like the hippocampus support this "true episodic" reinstatement. Here we show that neural activity patterns for unique word-scene combinations encountered during encoding are reinstated in human parahippocampal cortex (PhC) during retrieval. Critically, this reinstatement occurs when word-scene combinations are successfully recollected (even though the original scene is not visually presented) and does not encompass other stimulus domains (such as word-color associations). Finally, the degree of PhC reinstatement across retrieval events correlated with hippocampal activity, consistent with a role of the hippocampus in coordinating pattern completion in cortical regions.

  4. Sputtering of water ice

    DEFF Research Database (Denmark)

    Baragiola, R.A.; Vidal, R.A.; Svendsen, W.

    2003-01-01

    We present results of a range of experiments of sputtering of water ice together with a guide to the literature. We studied how sputtering depends on the projectile energy and fluence, ice growth temperature, irradiation temperature and external electric fields. We observed luminescence from...

  5. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions...

  6. Turning into Ice

    Science.gov (United States)

    Pietsch, Renée B.; Hanlon, Regina; Bohland, Cynthia; Schmale, David G., III

    2016-01-01

    This article describes an interdisciplinary unit in which students explore biological "ice nucleation"--by particles that cause water to freeze at temperatures above -38°C--through the lens of the microbial ice nucleator "Pseudomonas syringae." Such This activity, which aligns with the "Next Generation Science…

  7. Papillary thyroid microcarcinoma in a thyroid pyramidal lobe

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Tae Kwan; Kim, Dong Wook; Park, Ha Kyoung; Jung, Soo Jin [Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2014-12-15

    We report an extremely rare case of papillary thyroid microcarcinoma (PTMC) in the thyroid pyramidal lobe (TPL). A 48-year-old woman underwent ultrasound-guided fine-needle aspiration for a small thyroid nodule in the right lobe in local clinic, and it revealed a malignant cytology. On preoperative ultrasonography for tumor staging in our hospital, another small suspiciously malignant hypoechoic nodule was detected in the left TPL. Total thyroidectomy and central nodal dissection were performed. Histopathology confirmed PTMCs in the left TPL and both thyroid lobes. Ultrasonography for TPL should be required for complete evaluation of possible multifocality of thyroid malignancy.

  8. Estudios florísticos y ecológicos sobre las algas de agua dulce de turberas de Tierra del Fuego

    OpenAIRE

    Mataloni, María Gabriela

    1994-01-01

    En esta Tesis Doctoral se realizan diversas investigaciones florísticas y ecológicas sobre las algas de turberas de Sphagnum de la provincia de Tierra Fuego. Para ello se condijeron básicamente dos trabajos. en la primera parte se estudiaron ocho ojos de agua pertenecientes a siete turberas ubicadas en el sur de Tierra del Fuego. En cada una de ellas se muestrearon tanto el fitoplancton del agua libre como las algas que viven asociadas a Sphagnum a lo largo de un gradiente ambiental caracteri...

  9. El acaparamiento de tierras como proceso dinámico. Las estrategias de los actores en contextos de estancamiento económico

    OpenAIRE

    Carla Gras; Daniel M. Cáceres

    2017-01-01

    Este artículo pretende contribuir a la comprensión de los procesos de acaparamiento de tierras. A partir de un análisis realizado en el norte de Córdoba (Argentina), se sugiere que dicho fenómeno: (a) no es lineal, uniforme ni se incrementa de manera sostenida en el tiempo; y (b) no se limita a la concentración de tierras sino que integra recursos estratégicos (financieros, tecnológicos, gerenciales) que convergen en el objetivo más general de acaparamiento de capital. Analizamos una dinámica...

  10. El Límite a la Protección de las Tierras Indígenas de la Ley 19.253

    Directory of Open Access Journals (Sweden)

    Mario Salamanca Huenchullán

    Full Text Available Este trabajo aborda el tema del límite a la protección de las tierras indígenas, que como una exigencia del interés nacional introduce en la legislación chilena la Ley Indígena 19.253, en su relación con la expropiación para la construcción de obras públicas, que en virtud de la utilidad pública se construyen sobre estas mismas tierras.

  11. Turbulent measurements in the lobe mixer of a turbofan engine. Turbofan engine lobe mixer nagare no ranryu keisoku

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Makoto; Ogawa, Yuji; Arakawa, Chuichi; Tagori, Tetsuo [Ishikawajima-Harima Heavy Industries, Co., Ltd., Tokyo, (Japan) Nippon Steel Corp., Tokyo, (Japan) The Univ. of Tokyo, Tokyo, (Japan). Faculty of Engineering The Univ. of Tsukuba, Tsukuba, (Japan)

    1990-01-25

    In order to examine the flow generated by the lobe mixer of a turbofan engine precisely, after measuring a three dimensional turbulent flow by a hot-wire anemometer, the mixing process of a bypass flow and a core flow with cross-sectional vortexes, and factors generating the vortex were clarified experimentally using the scale model of an exhaust duct with the lobe mixer. As a result, the mixing process was strongly affected by a lobe tip figure and a lobe figure near a center-body, and affected by the minimum gap between the lobe and center-body. The subsequent mixing process was scarcely affected by the ratio of a core flow velocity to a bypass flow one, although strongly affected by flow conditions on a lobe surface. Since the lobe mixer promoted the mixing around a center axis shifting a fast core flow outwards, it was unfavorable to mixing, however, it was expected to be useful for reducing engine jet noise. 3 refs., 7 figs.

  12. GLERL Radiation Transfer Through Freshwater Ice

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radiation transmittance (ratio of transmitted to incident radiation) through clear ice, refrozen slush ice and brash ice, from ice surface to ice-water interface in...

  13. Torque and Axial Loading Physics for Measuring Atmospheric Icing Load and Icing Rate

    OpenAIRE

    Mughal, Umair Najeeb; Virk, Muhammad Shakeel

    2015-01-01

    Measuring icing load and icing rate are important parameters for an atmospheric icing sensor. A new icing sensor has recently been designed and developed at Narvik University College for measuring atmospheric icing rate, icing load and icing type. Unlike the existing atmospheric icing sensors commercially available in market, which uses the axial loading for measuring icing load and icing rate, this new sensory system measures icing load and icing rate using the torque loading physics. The pe...

  14. Modelling snow ice and superimposed ice on landfast sea ice in Kongsfjorden, Svalbard

    Directory of Open Access Journals (Sweden)

    Caixin Wang

    2015-08-01

    Full Text Available Snow ice and superimposed ice formation on landfast sea ice in a Svalbard fjord, Kongsfjorden, was investigated with a high-resolution thermodynamic snow and sea-ice model, applying meteorological weather station data as external forcing. The model shows that sea-ice formation occurs both at the ice bottom and at the snow/ice interface. Modelling results indicated that the total snow ice and superimposed ice, which formed at the snow/ice interface, was about 14 cm during the simulation period, accounting for about 15% of the total ice mass and 35% of the total ice growth. Introducing a time-dependent snow density improved the modelled results, and a time-dependent oceanic heat flux parameterization yielded reasonable ice growth at the ice bottom. Model results suggest that weather conditions, in particular air temperature and precipitation, as well as snow thermal properties and surface albedo are the most critical factors for the development of snow ice and superimposed ice in Kongsfjorden. While both warming air and higher precipitation led to increased snow ice and superimposed ice forming in Kongsfjorden in the model runs, the processes were more sensitive to precipitation than to air temperature.

  15. Evaluación del efecto insecticida de tierra de diatomeas sobre Triatoma infestans (Hemíptera, Reduviidae

    Directory of Open Access Journals (Sweden)

    Mariana L Bilbao

    2007-04-01

    Full Text Available El Triatoma infestans es el principal vector de la enfermedad de Chagas en Argentina. La tierra de diatomeas (TD es un producto natural que se comercializa actualmente con fines insecticidas y que produce la muerte por deshidratación. Se evaluó la eficacia insecticida de TD al 60% de pureza, proveniente del yacimiento La Iglesiana (San Juan, Argentina sobre ninfas V y adultos de T.infestans. Se ensayaron dos dosis: 112,5 g/m2 (T1 y 225 g/m2 (T2, con cuatro réplicas por tratamiento, con cinco ejemplares, incluyendo los controles (TC en el laboratorio. Se contaron los individuos vivos y muertos durante cinco días. No se encontró diferencias en la mortalidad (ANOVA, p>0,05 en los adultos (T1: 40%, T2: 25% y TC: 30% ni en las ninfas V (T1: 10%, T2: 15% y TC: 10%. Se concluye que la tierra de diatomeas del yacimiento La Iglesiana, en las condiciones de laboratorio evaluadas, no posee capacidad insecticida sobre T.infestans.

  16. Crecimiento ganadero y ocupación de tierras públicas, causas de conflictividad en la frontera bonaerense

    Directory of Open Access Journals (Sweden)

    Fernando Enrique Barba

    2007-01-01

    Full Text Available Sin dudas, la forma más visible de violencia practicada en la frontera de Buenos Aires durante los siglos XVIII y XIX fue la guerra entre el blanco y las diferentes parcialidades indígenas. Si bien puede afirmarse en sentido amplio que dicha guerra fue permanente, esta se intensificó en momentos determinados coincidentes con lo que podemos calificar, en rasgos generales, períodos de expansión ganadera. La presente colaboración intenta señalar entonces cuatro momentos en el proceso de expansión ganadera cuyas características generales fueron el aumento de los rebaños y ocupación de nuevas tierras, siendo estos hechos seguidos por la reacción de los indios quienes incrementaron los malones, pequeños en general y eventualmente masivos, en busca de los ganados de todo tipo existentes en las estancias bonaerenses. Los cuatro períodos a estudiar son: 1º a partir de las últimas vaquerías (1718; 2º la formación del virreinato y las nuevas condiciones de comercio; 3º la expansión ganadera a partir de 1810 y la ocupación de tierras más allá del Salado y 4º y el gran crecimiento a partir de Caseros

  17. Plan de manejo sostenible de tierra para la producción de leche en la UBPC Aguadita, Cienfuegos, Cuba

    Directory of Open Access Journals (Sweden)

    Eligia de la C Cuellar

    Full Text Available Se realizó un estudio en la UBPC Aguadita, del municipio Rodas _provincia Cienfuegos, Cuba_, con el objetivo de elaborar un plan de manejo sostenible del suelo para incrementar la producción de leche. Se utilizó la guía contenida en el manual de procedimientos para la implementación del manejo sostenible de tierra. Los pasos de la guía permitieron concebir una investigación no experimental, de tipo correlacional/múltiple, en la que se utilizaron métodos teóricos y prácticos con sus correspondientes técnicas (entrevistas, encuestas, revisión documental, observación directa; y se realizaron mediciones en el lugar, con la aplicación de diez herramientas metodológicas. Se demostró que la baja producción de leche en la UBPC es causada fundamentalmente por la degradación de los suelos, la mala calidad de los pastos y la deficiente gestión del conocimiento, lo que coincide con la principal barrera para la aplicación del manejo sostenible de tierra. A partir de estos resultados se elaboró el plan de manejo sostenible, como herramienta que contribuye a desarrollar acciones que mitiguen el impacto negativo de la degradación de suelos en el rendimiento lechero de la unidad.

  18. [Two cases of mesial temporal lobe epilepsy associated with old intracerebral hemorrhage in the lateral temporal lobe without "dual pathology"].

    Science.gov (United States)

    Morioka, T; Nishio, S; Hisada, K; Muraishi, M; Ishibashi, H; Mamiya, K; Ohfu, M; Fukui, M

    1998-05-01

    Two cases of intractable temporal lobe epilepsy associated with old intracerebral hemorrhage in the lateral temporal lobe were reported. Although preoperative magnetic resonance imaging (MRI) failed to reveal hippocampal atrophy with T2 hyperintensity, electrocorticographic (ECoG) recording with chronic invasive subdural electrodes indicated the mesial temporal lobe to be an ictal onset zone. After anterior temporal lobectomy involving the lesion and hippocampectomy, the patients became seizure-free. Hippocampal sclerosis, namely "dual pathology", was not noted on histological examination. Careful ECoG recording with chronic subdural electrodes is mandatory even when the preoperative MRI does not demonstrate the radiological hippocampal sclerosis.

  19. Pediatric frontal lobe epilepsy : white matter abnormalities and cognitive impairment

    NARCIS (Netherlands)

    Braakman, H.M.H.; Vaessen, M.J.; Jansen, J.F.A.; Debeij-van Hall, M.H.J.A.; Louw, de A.; Hofman, P.A.M.; Vles, J.S.H.; Aldenkamp, A.P.; Backes, W.H.

    2014-01-01

    Objectives: Cognitive impairment is frequent in children with frontal lobe epilepsy (FLE). Its etiology remains unknown. With diffusion tensor imaging, we have studied cerebral white matter properties and associations with cognitive functioning in children with FLE and healthy controls.

  20. Genetics Home Reference: autosomal dominant nocturnal frontal lobe epilepsy

    Science.gov (United States)

    ... with ADNFLE have experienced psychiatric disorders (such as schizophrenia), behavioral problems, or intellectual disability. It is unclear ... Epilepsy Society Citizens United for Research in Epilepsy (CURE) GeneReviews (1 link) Autosomal Dominant Nocturnal Frontal Lobe ...

  1. Magnetic resonance tomography (MRT) for lesions of the temporal lobes

    International Nuclear Information System (INIS)

    Schoerner, W.; Felix, R.; Meencke, H.J.; Freie Univ. Berlin; Freie Univ. Berlin

    1985-01-01

    A comparative study between magnetic resonance tomography (MRT) and CT was carried out in 16 patients with temporal lobe epilepsy. The MRT studies were performed on a 0.35 T Magnetom with T.1 modes in a coronal plane. MRT proved to the superior to CT. CT demonstrated a discrete temporal lobe lesion in three patients and MRT in four patients. In addition, unilateral atrophy of the temporal lobe was demonstrated by MRT in six cases; these could not be diagnosed by CT. The lack of artifacts near the skull base, the possibility of producing coronal sections and the excellent tissue differential of MRT provide the basis for improved diagnosis of lesions in the temporal lobes. (orig.) [de

  2. Cognitive impairments in patients with intractable temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Mahgol Tavakoli

    2011-01-01

    Conclusions: These findings indicated that WMS-III and WAIS-R can differentiate patients with refractory temporal lobe epilepsy from normal subjects. However, the obtained cognitive profile could not differentiate between the right and the left TLE.

  3. Spike voltage topography in temporal lobe epilepsy.

    Science.gov (United States)

    Asadi-Pooya, Ali A; Asadollahi, Marjan; Shimamoto, Shoichi; Lorenzo, Matthew; Sperling, Michael R

    2016-07-15

    We investigated the voltage topography of interictal spikes in patients with temporal lobe epilepsy (TLE) to see whether topography was related to etiology for TLE. Adults with TLE, who had epilepsy surgery for drug-resistant seizures from 2011 until 2014 at Jefferson Comprehensive Epilepsy Center were selected. Two groups of patients were studied: patients with mesial temporal sclerosis (MTS) on MRI and those with other MRI findings. The voltage topography maps of the interictal spikes at the peak were created using BESA software. We classified the interictal spikes as polar, basal, lateral, or others. Thirty-four patients were studied, from which the characteristics of 340 spikes were investigated. The most common type of spike orientation was others (186 spikes; 54.7%), followed by lateral (146; 42.9%), polar (5; 1.5%), and basal (3; 0.9%). Characteristics of the voltage topography maps of the spikes between the two groups of patients were somewhat different. Five spikes in patients with MTS had polar orientation, but none of the spikes in patients with other MRI findings had polar orientation (odds ratio=6.98, 95% confidence interval=0.38 to 127.38; p=0.07). Scalp topographic mapping of interictal spikes has the potential to offer different information than visual inspection alone. The present results do not allow an immediate clinical application of our findings; however, detecting a polar spike in a patient with TLE may increase the possibility of mesial temporal sclerosis as the underlying etiology. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. SPITZER OBSERVATIONS OF HOTSPOTS IN RADIO LOBES

    International Nuclear Information System (INIS)

    Werner, Michael W.; Murphy, David W.; Livingston, John H.; Gorjian, Varoujan; Jones, Dayton L.; Meier, David L.; Lawrence, Charles R.

    2012-01-01

    We have carried out a systematic search with Spitzer Warm Mission and archival data for infrared emission from the hotspots in radio lobes that have been described by Hardcastle et al. These hotspots have been detected with both radio and X-ray observations, but an observation at an intermediate frequency in the infrared can be critical to distinguish between competing models for particle acceleration and radiation processes in these objects. Between the archival and warm mission data, we report detections of 18 hotspots; the archival data generally include detections at all four IRAC bands, the Warm Mission data only at 3.6 μm. Using a theoretical formalism adopted from Godfrey et al., we fit both archival and warm mission spectral energy distributions (SEDs)—including radio, X-ray, and optical data from Hardcastle as well as the Spitzer data—with a synchrotron self-Compton (SSC) model, in which the X-rays are produced by Compton scattering of the radio frequency photons by the energetic electrons which radiate them. With one exception, an SSC model requires that the magnetic field be less or much less than the equipartition value which minimizes total energy and has comparable amounts of energy in the magnetic field and in the energetic particles. This conclusion agrees with those of comparable recent studies of hotspots, and with the analysis presented by Hardcastle et al. We also show that the infrared data rule out the simplest synchrotron-only models for the SEDs. We briefly discuss the implications of these results and of alternate interpretations of the data.

  5. Cognitive dysfunctions in occipital lobe epilepsy compared to temporal lobe epilepsy.

    Science.gov (United States)

    Santangelo, Gabriella; Trojano, Luigi; Vitale, Carmine; Improta, Ilaria; Alineri, Irma; Meo, Roberta; Bilo, Leonilda

    2017-06-01

    To compare cognitive profiles of occipital lobe epilepsy (OLE) and temporal lobe epilepsy (TLE) and to investigate whether impairment of visuospatial functions is a specific deficit of OLE. Eighteen patients with OLE, 18 patients with TLE, and 18 controls underwent a neuropsychological battery assessing memory, visuospatial functions, and frontal/executive functions. Multivariate analysis evidenced poorer performance of patients with TLE and patients with OLE relative to controls on tasks assessing verbal and non-verbal long-term memory, frontal functions, and visuospatial functions. Patients with OLE had poorer performance than patients with TLE on visuospatial tasks, whereas patients with TLE performed worse than patients with OLE on verbal long-term memory test. Discriminant analysis identified two canonical discriminant functions: The first explained 53.3% of the variance, and the second explained 46.7% of the variance. The first function included verbal and non-verbal memory tests distinguishing controls from both OLE and TLE, whereas the second factor including a visuoconstructional test distinguished OLE from TLE and controls. The results demonstrate that visuoconstructional dysfunction is related to OLE and support the idea that alterations of occipito-parietal stream may be specific to patients with OLE. © 2015 The British Psychological Society.

  6. Patterns of verbal learning and memory in children with intractable temporal lobe or frontal lobe epilepsy.

    Science.gov (United States)

    Fuentes, Amanda; Smith, Mary Lou

    2015-12-01

    The objective of this study was to provide a better understanding of the verbal learning and memory (VLM) patterns that might differentiate children with frontal lobe epilepsy (FLE) from children with temporal lobe epilepsy (TLE) and to examine the impact of variables thought to influence outcomes (seizure laterality, age at seizure onset, age at assessment, epilepsy duration, number of antiepileptic drugs). Retrospective analyses were carried out for children with intractable unilateral TLE (n=100) and FLE (n=27) who completed standardized measures of VLM entailing lists of single words or lists of word pairs. Mean intelligent quotients and VLM scores on single words fell within the average range for both groups, whereas scores fell within the low average to borderline range on word pairs. No significant overall differences in VLM were found between the group with TLE and the group with FLE. Older age at assessment and older age at seizure onset were generally associated with better VLM in both groups but were related to better performance in a number of indices in the group with TLE and only fewer intrusions in the group with FLE. The VLM profiles of children with TLE and FLE are generally similar. Older age at assessment and older age at seizure onset have a favorable impact on both groups but are related to better encoding, retrieval, and monitoring processes for the group with TLE and improved memory monitoring (i.e., as indicated by fewer intrusions) in the group with FLE. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Mirror Focus in a Patient with Intractable Occipital Lobe Epilepsy

    OpenAIRE

    Kim, Jiyoung; Shin, Hae kyung; Hwang, Kyoung Jin; Choi, Su Jung; Joo, Eun Yeon; Hong, Seung Bong; Hong, Seung Chul; Seo, Dae-Won

    2014-01-01

    Mirror focus is one of the evidence of progression in epilepsy, and also has practical points for curative resective epilepsy surgery. The mirror foci are related to the kindling phenomena that occur through interhemispheric callosal or commissural connections. A mirror focus means the secondary epileptogenic foci develop in the contralateral hemispheric homotopic area. Thus mirror foci are mostly reported in patients with temporal or frontal lobe epilepsy, but not in occipital lobe epilepsy....

  8. Altered organization of face processing networks in temporal lobe epilepsy

    Science.gov (United States)

    Riley, Jeffrey D.; Fling, Brett W.; Cramer, Steven C.; Lin, Jack J.

    2015-01-01

    SUMMARY Objective Deficits in social cognition are common and significant in people with temporal lobe epilepsy (TLE), but the functional and structural underpinnings remain unclear. The present study investigated how the side of seizure focus impacts face processing networks in temporal lobe epilepsy. Methods We used functional magnetic resonance imaging (fMRI) of a face processing paradigm to identify face responsive regions in 24 individuals with unilateral temporal lobe epilepsy (Left = 15; Right = 9) and 19 healthy controls. fMRI signals of face responsive regions ispilateral and contralateral to the side of seizure onset were delineated in TLE and compared to the healthy controls with right and left side combined. Diffusion tensor images were acquired to investigate structural connectivity between face regions that differed in fMRI signals between the two groups. Results In temporal lobe epilepsy, activation of the cortical face processing networks varied according to side of seizure onset. In temporal lobe epilepsy, the laterality of amygdala activation was shifted to the side contralateral to the seizure focus while controls showed no significant asymmetry. Furthermore, compared to controls, patients with TLE showed decreased activation of the occipital face responsive region in the ipsilateral side and an increased activity of the anterior temporal lobe in the contralateral side to the seizure focus. Probabilistic tractography revealed that the occipital face area and anterior temporal lobe are connected via the inferior longitudinal fasciculus, which in individuals with temporal lobe epilepsy showed reduced integrity. Significance Taken together, these findings suggest that brain function and white matter integrity of networks subserving face processing are impaired on the side of seizure onset, accompanied by altered responses on the side contralateral to the seizure. PMID:25823855

  9. A comparison of occipital and temporal lobe epilepsies.

    Science.gov (United States)

    Appel, S; Sharan, A D; Tracy, J I; Evans, J; Sperling, M R

    2015-10-01

    Differentiating between occipital lobe epilepsy (OLE) and temporal lobe epilepsy (TLE) is often challenging. This retrospective case-control study compares OLE to TLE and explores markers that suggest the diagnosis of OLE. We queried the Jefferson Epilepsy Center surgery database for patients who underwent a resection that involved the occipital lobe. For each patient with OLE, three sequential case-control patients with TLE were matched. Demographic characteristics, symptoms, electrophysiological findings, imaging findings, and surgical outcome were compared. Nineteen patients with OLE and 57 patients with TLE were included in the study. Visual symptoms were unique to patients with OLE (8/19) and were not reported by patients with TLE (P Occipital interictal spikes (IIS) were found only in one-third of the patients with OLE (6/19) and in no patients with TLE (P lobe were found in five of 19 patients with OLE vs one of 57 patients with TLE (P = 0.003). IIS involved more than one lobe of the brain in most patients with OLE (11/19) but only in nine of 57 the TLE group. (P = 0.0003) Multilobar resection was needed in most patients with OLE (15/19), typically including the temporal lobe, but in only one of the patients with TLE (P Occipital lobe epilepsy is difficult to identify and may masquerade as temporal lobe epilepsy. Visual symptoms and occipital findings in the EEG suggest the diagnosis of OLE, but absence of these features, does not exclude the diagnosis. When posterior temporal EEG findings or multilobar involvement occurs, the diagnosis of OLE should be considered. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Accessory hepatic lobe simulating a left hemidiaphragmatic tumor

    International Nuclear Information System (INIS)

    Kuroiwa, Toshiro; Hirata, Hitoshi; Iwashita, Akinori; Yasumori, Kotaro; Mogami, Hiroshi; Teraoka, Hiroaki

    1984-01-01

    A 72-year-old woman with a 20-year history of neuralgia was confirmed at surgery to have a tumor in the left hemidiaphragmatic region which was connected with the left lobe of the liver. Reassessment of radiological diagnosis after surgery revealed that hepatobiliary scintigraphy and computed tomography using left anterior oblique scanning are useful in differentiating the accessory hepatic lobe of the liver from a tumor and in confirming the diagnosis, respectively. (Namekawa, K.)

  11. Versive seizures in occipital lobe epilepsy: lateralizing value and pathophysiology.

    Science.gov (United States)

    Usui, Naotaka; Mihara, Tadahiro; Baba, Koichi; Matsuda, Kazumi; Tottori, Takayasu; Umeoka, Shuichi; Kondo, Akihiko; Nakamura, Fumihiro; Terada, Kiyohito; Usui, Keiko; Inoue, Yushi

    2011-11-01

    To clarify the value of versive seizures in lateralizing and localizing the epileptogenic zone in patients with occipital lobe epilepsy, we studied 13 occipital lobe epilepsy patients with at least one versive seizure recorded during preoperative noninvasive video-EEG monitoring, who underwent occipital lobe resection, and were followed postoperatively for more than 2 years with Engel's class I outcome. The videotaped versive seizures were analyzed to compare the direction of version and the side of surgical resection in each patient. Moreover, we examined other motor symptoms (partial somatomotor manifestations such as tonic and/or clonic movements of face and/or limbs, automatisms, and eyelid blinking) associated with version. Forty-nine versive seizures were analyzed. The direction of version was always contralateral to the side of resection except in one patient. Among accompanying motor symptoms, partial somatomotor manifestations were observed in only five patients. In conclusion, versive seizure is a reliable lateralizing sign indicating contralateral epileptogenic zone in occipital lobe epilepsy. Since versive seizures were accompanied by partial somatomotor manifestations in less than half of the patients, it is suggested that the mechanism of version in occipital lobe epilepsy is different from that in frontal lobe epilepsy. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Bicavitary effusion secondary to liver lobe torsion in a dog

    Directory of Open Access Journals (Sweden)

    Khan Z

    2016-04-01

    Full Text Available Zaheda Khan,1 Kathryn Gates,2 Stephen A Simpson,31Emergency and Critical Care, Animal Specialty and Emergency Center, Los Angeles, CA, 2Emergency and Critical Care, Advanced Critical Care, Emergency and Specialty Services, Culver City, CA 3Emergency and Critical Care, Southern California Veterinary Specialty Hospital, Irvine, CA, USA Abstract: We described the diagnosis and successful treatment of pleural and peritoneal effusion secondary to liver lobe torsion in a dog. A 12-year-old female spayed Borzoi dog was referred for heart failure. Emergency room thoracic and abdominal ultrasound showed a large volume of pleural effusion with mild peritoneal effusion and an abdominal mass. Pleural fluid analysis classified the effusion as exudative. A complete ultrasound revealed mild peritoneal effusion and decreased blood flow to the right liver lobe. Other causes of bicavitary effusion were ruled out based on blood work, ultrasound, echocardiogram, and computed tomography. The patient was taken to surgery and diagnosed with caudate liver lobe torsion and had a liver lobectomy. At the 2-week postoperative recheck, the patient was doing well and there was complete resolution of the pleural effusion. Liver lobe torsion is a rare occurrence in dogs and can be difficult to diagnose. Clinical signs are nonspecific for liver lobe torsion and patients may present in respiratory distress with significant pleural fluid accumulation. When assessing patients with pleural and peritoneal effusion, liver lobe torsion should be considered as a differential diagnosis.Keywords: pleural effusion, peritoneal effusion, hepatic torsion

  13. Transient simulation in interior flow field of lobe pump

    International Nuclear Information System (INIS)

    Li, Y B; Sang, X H; Shen, H; Jia, K; Meng, Q W

    2013-01-01

    The subject of this paper is mainly focused on the development and control of the double folium and trifolium lobe pump profiles by using the principle of involute engagement and use CAD to get an accurate involute profile. We use the standard k-ε turbulence model and PISO algorithm based on CFD software FLUENT. The dynamic mesh and UDF technology is introduced to simulate the interior flow field inside a lobe pump, and the variation of interior flow field under the condition of the lobe rotating is analyzed. We also analyse the influence produced by the difference in lobes, and then reveal which lobe is best. The results show that dynamic variation of the interior flow field is easily obtained by dynamic mesh technology and the distribution of its pressure and velocity. Because of the small gaps existing between the rotors and pump case, the higher pressure area will flow into the lower area though the small gaps which cause the working area keep with higher pressure all the time. Both of the double folium and trifolium are existing the vortex during the rotting time and its position, size and shape changes all the time. The vortexes even disappear in a circle period and there are more vortexes in double folium lobe pump. The velocity and pressure pulsation of trifolium pump are lower than that of the double folium

  14. Medical image of the week: right middle lobe syndrome

    Directory of Open Access Journals (Sweden)

    Cristan EA

    2016-05-01

    Full Text Available No abstract available. Article truncated at 150 words. A 73 year-old woman, a lifetime non-smoker, presented to the pulmonary clinic with chronic dyspnea on exertion and cough. Physical exam was unremarkable and pulmonary function testing showed normal spirometry. A chest radiograph revealed calcified mediastinal adenopathy and increased density in the right middle lobe region (Figure 1. A computed tomography scan of the chest revealed significant narrowing of the right middle lobe bronchus with partial atelectasis and prominent calcified mediastinal lymphadenopathy (Figure 2. Bronchoscopy showed no endobronchial lesions but there was evidence of extrinsic compression surrounding the right middle lobe orifice. An endobronchial biopsy revealed noncaseating granulomas. Bronchoscopy cultures and cytology were negative and this was presumed to be from a previous infection with histoplasmosis given the patient’s long-term residence in an endemic area. Given chronic narrowing of right middle lobe bronchus with persistent atelectasis of the right middle lobe, the patient was diagnosed with right middle lobe syndrome. ...

  15. Coulombic charge ice

    Science.gov (United States)

    McClarty, P. A.; O'Brien, A.; Pollmann, F.

    2014-05-01

    We consider a classical model of charges ±q on a pyrochlore lattice in the presence of long-range Coulomb interactions. This model first appeared in the early literature on charge order in magnetite [P. W. Anderson, Phys. Rev. 102, 1008 (1956), 10.1103/PhysRev.102.1008]. In the limit where the interactions become short ranged, the model has a ground state with an extensive entropy and dipolar charge-charge correlations. When long-range interactions are introduced, the exact degeneracy is broken. We study the thermodynamics of the model and show the presence of a correlated charge liquid within a temperature window in which the physics is well described as a liquid of screened charged defects. The structure factor in this phase, which has smeared pinch points at the reciprocal lattice points, may be used to detect charge ice experimentally. In addition, the model exhibits fractionally charged excitations ±q/2 which are shown to interact via a 1/r potential. At lower temperatures, the model exhibits a transition to a long-range ordered phase. We are able to treat the Coulombic charge ice model and the dipolar spin ice model on an equal footing by mapping both to a constrained charge model on the diamond lattice. We find that states of the two ice models are related by a staggering field which is reflected in the energetics of these two models. From this perspective, we can understand the origin of the spin ice and charge ice ground states as coming from a dipolar model on a diamond lattice. We study the properties of charge ice in an external electric field, finding that the correlated liquid is robust to the presence of a field in contrast to the case of spin ice in a magnetic field. Finally, we comment on the transport properties of Coulombic charge ice in the correlated liquid phase.

  16. Checklist of the Discomycetes (Fungi of Patagonia, Tierra del Fuego and adjacent antarctic areas

    Directory of Open Access Journals (Sweden)

    Irma J. Gamundí

    2004-01-01

    Full Text Available La información brindada en este catálogo consiste en registrar las especies de hongos pertenecientes a los órdenes Cyttariales, Helotiales, Ostropales, Pezizales, Rhytismatales y Thelebolales (Discomycetes coleccionadas en Patagonia, Tierra del Fuego y áreas adyacentes antárticas (Patagonia. Además datos sobre sus organismos asociados fueron localizados, resumidos, validados y editados. Las fuentes de información fueron las exsiccatae depositadas en colecciones de Argentina y otros países y de las publicaciones listadas en la bibliografía. Otros registros derivaron de observaciones de campo sobre material fresco y colecciones de referencia. La información fue acumulada en un sistema computarizado relacional de datos taxonómicos, nomenclaturales, bibliográficos, de distribución geográfica y de observaciones biológicas. Este sistema permite la acumulación de datos paralelos en diferentes idiomas, y distingue la información original de la opinión corriente de lo que puede significar esa información. En la Biological Records Database, 5029 registros fueron creados para observaciones sobre la ocurrencia temporal y espacial de los organismos vivos de la región. De éstos, 2613 corresponden a registros de colecciones de Discomycetes de la Patagonia y Tierra del Fuego, con la siguiente distribución: 1854 para a la Argentina, 687 para Chile y 72 para áreas adyacentes antárticas. Excluyendo los sinónimos, los Discomycetes están representados por 361 especies y taxones subespecíficos (160 géneros, 22 familias y 7 órdenes. Los registros remanentes fueron de organismos asociados con los Discomycetes: 163 animales (8 especies, 8 géneros, 6 familias y 5 órdenes; 2 Chromista; 223 hongos (52 especies, 54 géneros, 26 familias y 13 ódenes; 2028 plantas (159 especies, 122 géneros, 59 familias y 39 órdenes. Cada uno de estos taxones (y cada sinónimo conocido está representado por un registro separado en la Base de Datos Taxon

  17. Modelo para evaluar la calidad de las tierras: caso del cultivo de papa

    Directory of Open Access Journals (Sweden)

    Martínez Luis Joel

    2006-06-01

    Hidden="false" UnhideWhenUsed="false" QFormat="true" Name="Intense Emphasis" />

    Dentro de la busqueda de la sostenibilidad y la competitividad de la agricultura, la evaluacion de la calidad de las tierras es un aspecto basico que permite tomar decisiones sobre  las areas mas apropiadas para ubicar los cultivos y sobre los procesos de degradación de las tierras, con el fin de tomar medidas para su manejo y conservacion. En esta investigacion se

  18. Creep of ice: further studies

    International Nuclear Information System (INIS)

    Heard, H.C.; Durham, W.B.; Kirby, S.H.

    1987-01-01

    Detailed studies have been done of ice creep as related to the icy satellites, Ganymede and Callisto. Included were: (1) the flow of high-pressure water ices II, III, and V, and (2) frictional sliding of ice I sub h. Work was also begun on the study of the effects of impurities on the flow of ice. Test results are summarized

  19. Vortex ice in nanostructured superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Reichhardt, Charles [Los Alamos National Laboratory; Reichhardt, Cynthia J [Los Alamos National Laboratory; Libal, Andras J [Los Alamos National Laboratory

    2008-01-01

    We demonstrate using numerical simulations of nanostructured superconductors that it is possible to realize vortex ice states that are analogous to square and kagome ice. The system can be brought into a state that obeys either global or local ice rules by applying an external current according to an annealing protocol. We explore the breakdown of the ice rules due to disorder in the nanostructure array and show that in square ice, topological defects appear along grain boundaries, while in kagome ice, individual defects appear. We argue that the vortex system offers significant advantages over other artificial ice systems.

  20. Expansión estatal, política de tierras y desarrollo de la repartición topográfica en Buenos Aires, siglo XIX

    Directory of Open Access Journals (Sweden)

    Valeria Araceli D'Agostino

    2014-11-01

    Full Text Available Este artículo aborda la política de tierras del Estado provincial bonaerensey su relación con el proceso de conformación de la repartición topográfi ca,tomando como punto de partida el contexto de expansión territorial y deincorporación de tierras a la economía provincial abierto luego de la rupturadel vínculo colonial. Se considera que la centralidad de la problemática dela tierra en este contexto impulsó la temprana organización de la reparticióndestinada a: realizar las tareas de reconocimiento, mensura y delimitación delos territorios de dominio público y privado, elaborar un catastro territorial,controlar el traspaso de tierras públicas a particulares, perfeccionar el trazadode pueblos y ejidos y regular las actividades de los agentes encargados de lasmismas, entre otras.

  1. Organización territorial y distribución de la tierra en la comunidad de San Felipe Otlaltepec, Puebla, México

    Directory of Open Access Journals (Sweden)

    Jesús García Maceda

    2014-01-01

    Full Text Available San Felipe Otlaltepec, una comunidad indígena Popoloca del estado de Puebla, organiza su territorio en secciones, una unidad territorial colonial. Esta organización es la base de la apropiación del territorio urbano y de las tierras agrícolas. Con entrevistas y fotografías aéreas, se construyó un modelo de la conformación original y actual de las viviendas de las secciones y de la apropiación de la tierra, para su comparación. Actualmente, se observa una mezcla de viviendas de diferentes secciones, que no corresponde al arreglo original de las mismas. Situación similar se observó en la distribución de las tierras agrícolas. Estos cambios se deben principalmente a casamientos entre miembros de diferentes secciones, los cuales cambian la posesión de la tierra y la pertenencia a una sección determinada. A pesar de la mezcla de viviendas de diferentes secciones, los entrevistados manifestaron un sentido profundo de pertenencia a la sección a la que pertenecen formalmente.

  2. Regulación en el uso de la tierra con fines preventivos en los alrededores del cuadrante de la antigua comunidad de Cinchona, Alajuela, Costa Rica

    Directory of Open Access Journals (Sweden)

    Esquivel Valverde, Lidier

    2011-07-01

    Full Text Available La regulación del uso de la tierra permite establecer cuales lugares son aptas para el establecimiento de zonas habitacionales, comercios, industria, actividades agrícolas, actividades turísticas, entre otras, evitando incrementar la vulnerabilidad física o ambiental. El presente artículo se basa en un estudio realizado a la comunidad de Cinchona a raíz del sismo del año 2009, el cual, por las características topográficas y geológicas de la región, generó una cantidad alta de daños a la infraestructura y pérdida de vidas humanas, lo que propició la elaboración de una herramienta técnica normativa que regulara el uso de la tierra en esa zona. La investigación consideró aspectos como el uso de la tierra antes del sismo, tenencia de la tierra, producción agropecuaria, valor de la tierra, pendientes de terreno, geomorfología, capacidad de uso de la tierra, aguas subterráneas, zonas de vida y áreas silvestres y por último las amenazas más relevantes. Como resultado del estudio se presenta en el artículo un resumen de la regulación de tierra propuesta, la cual comprende el sector de Vieja Cinchona (zona devastada por el sismo y las microcuencas cercanas Land use regulations allow to identify suitable places to establish housing, commerce, industry, agricultural activities, and tourism, among others, avoiding to increase physical or environmental vulnerability. This article is based on a study developed at the Cinchona community after the 2009 earthquake, which due to the topographic and geological characteristics generated a lot of damages to infrastructures and losses of human lives. In this context, a normative technical tool was developed to regulate the land use in the zone. The investigation considered aspects such as land use before the earthquake, land possession, farming production, land value, land slopes, geomorphology, land use capacity, underground water, wild life areas and most relevant threats. As a result of

  3. Historia y memoria campesina: silencios y representaciones sobre la lucha por la tierra y la represión en Ongoy

    Directory of Open Access Journals (Sweden)

    Guido Chati

    2015-01-01

    Full Text Available Este artículo sostiene que hay espacios sociales en Perú donde se producen memorias alternativas sobre la violencia política que tuvo lugar entre 1980 y 2000. En Andahuaylas, Apurímac, las narrativas recurrentes hablan acerca de la servidumbre en la hacienda, de la movilización campesina por la restitución de sus tierras, la ocupación de tierras y sobre su violenta represión. Existe esta memoria victoriosa respecto de la ocupación de la tierra, al lado de una memoria de victimización respecto de la guerra interna. Sin embargo, esas representaciones han sido silenciadas a través de estudios oficiales sobre la memoria, que están tan de moda. En Ongoy, Andahuaylas, bajo la apariencia de un conflicto entre las comunidades y hacienda, se encuentran prácticas políticas campesinas en relación con el Estado. Los campesinos desarrollan redes con las instituciones del Estado, sindicatos, estudiantes, inmigrantes, partidos políticos y otros en busca de la restitución de sus tierras. Reúnen documentos que utilizan como apoyo de su memoria y de su precedencia en el territorio. Ellos muestran que la lucha por la tierra que relativamente termina en 1963 con la ocupación de la tierra, la masacre de los campesinos y la represión, tiene orígenes coloniales. Son historias y recuerdos que reconstruyen la lucha por la tierra como un acto heroico y se superponen con otras representaciones más recientes de la violencia política. Para analizar el proceso, reconstruyo lo ocurrido en Ongoy entre 1960 y 1969 en diálogo con los documentos que los campesinos reunieron y con los testimonios de los actores sobre la forma en que se da una lectura posterior a la violencia política.

  4. Ice Engineering Research Area

    Data.gov (United States)

    Federal Laboratory Consortium — Refrigerated Physical Modeling of Waterways in a Controlled EnvironmentThe Research Area in the Ice Engineering Facility at the Cold Regions Research and Engineering...

  5. Ice Cream Stick Math.

    Science.gov (United States)

    Paddock, Cynthia

    1992-01-01

    Described is a teaching technique which uses the collection of ice cream sticks as a means of increasing awareness of quantity in a self-contained elementary special class for students with learning disabilities and mild mental retardation. (DB)

  6. Global ice sheet modeling

    International Nuclear Information System (INIS)

    Hughes, T.J.; Fastook, J.L.

    1994-05-01

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed

  7. The Antartic Ice Borehole Probe

    Science.gov (United States)

    Behar, A.; Carsey, F.; Lane, A.; Engelhardt, H.

    2000-01-01

    The Antartic Ice Borehole Probe mission is a glaciological investigation, scheduled for November 2000-2001, that will place a probe in a hot-water drilled hole in the West Antartic ice sheet. The objectives of the probe are to observe ice-bed interactions with a downward looking camera, and ice inclusions and structure, including hypothesized ice accretion, with a side-looking camera.

  8. Evaluación de la tasa de infiltración en tierras agrícolas, forestales y de pastoreo en la subcuenca del río Shullcas

    Directory of Open Access Journals (Sweden)

    Guillermo Carlos Gómez

    2014-06-01

    Full Text Available Objetivos: Evaluar y determinar el uso del suelo con mayor tasa de infiltración en la subcuenca del río Shullcas en Huancayo. Métodos: Se desarrolló una investigación básica con diseño correlacional. Los usos actuales de la tierra fueron identificadas y demarcadas, según la normativa peruana de clasificación de tierras por su capacidad de uso mayor; en estas zonas se seleccionó 31 puntos de muestreo al azar usando las herramientas de software ArcGIS, en los que se midieron la infiltración empleando infiltrómetros de doble anillo, se registraron los tipos de cobertura vegetal y se tomaron muestras de suelo para analizar sus contenidos de arcilla, arena, limo y humedad; asimismo densidad aparente y porosidad en laboratorio. Resultados: Las tasas de infiltración promedio, según el tipo de uso de tierras, fueron: 14,04 cm/h para las tierras forestales; 12,42 cm/h para las tierras agrícolas y 2,07 cm/h para las tierras de pastoreo; además, solo el 12,63% de la subcuenca del río Shullcas tiene infiltración mayor a 0,2 cm/h. Conclusiones: No existe diferencia estadística significativa entre la tasa de infiltración de tierras forestales y agrícolas, pero si existe diferencias de la tasa de infiltración de tierras forestales y agrícolas respecto a la tasa de infiltración de tierras de pastoreo.

  9. A CLINICORADIOLOGICAL STUDY OF MIDDLE LOBE SYNDROME DUE TO TUBERCULOSIS

    Directory of Open Access Journals (Sweden)

    Saurabh Karmakar

    2016-09-01

    Full Text Available BACKGROUND Although pulmonary tuberculosis is a common disease in India, tuberculosis of right middle lobe is infrequent. Tuberculosis of the right middle lobe leading to chronic collapse is a cause of Right Middle Lobe syndrome. METHODS The patients attended Pulmonary Medicine Outdoor at Era’s Lucknow Medical College, Lucknow from April 2015 to March 2016. The purpose of this study is to describe the clinicoradiological features of patients of middle lobe syndrome due to tuberculosis. All patients presented with cough with or without expectoration, fever, chest pain, haemoptysis and constitutional symptoms like loss of appetite and weight. Chest X-ray PA view revealed ill-defined opacity abutting the right cardiac border. HRCT thorax was done in each case. The diagnosis of tuberculous aetiology was based on (1 History of chronic cough and fever, not responding to antibiotic therapy and constitutional symptoms, (2 A positive tuberculin test using 2 TU of PPD RT 23 and (3 Detection of acid fast bacilli by direct smear or Mycobacterium tuberculosis by polymerase chain reaction in bronchoalveolar lavage. RESULTS Out of 10 patients, 4 (40% were males and 6 (60% were females. The mean ages of the males were 55.8 years and females were 60.8 years and overall mean age was 59 years. Most of the patients were females and belonged to the middle age and old age group. ATT was started in all the patients. CONCLUSIONS Right middle lobe syndrome predominantly affects the older population and the female gender. Although tuberculosis is a common disease in India, Middle Lobe Syndrome is a very rare presentation of the disease. Due to non-specific symptoms and usually normal chest X-ray PA view in Right Middle Lobe Syndrome, we should keep a high index of suspicion to diagnose the condition.

  10. Decreased occipital lobe metabolism by FDG-PET/CT

    Science.gov (United States)

    Solnes, Lilja; Nalluri, Abhinav; Cohen, Jesse; Jones, Krystyna M.; Zan, Elcin; Javadi, Mehrbod S.; Venkatesan, Arun

    2017-01-01

    Objective: To compare brain metabolism patterns on fluorodeoxyglucose (FDG)-PET/CT in anti–NMDA receptor and other definite autoimmune encephalitis (AE) and to assess how these patterns differ between anti–NMDA receptor neurologic disability groups. Methods: Retrospective review of clinical data and initial dedicated brain FDG-PET/CT studies for neurology inpatients with definite AE, per published consensus criteria, treated at a single academic medical center over a 10-year period. Z-score maps of FDG-PET/CT were made using 3-dimensional stereotactic surface projections in comparison to age group–matched controls. Brain region mean Z scores with magnitudes ≥2.00 were interpreted as significant. Comparisons were made between anti–NMDA receptor and other definite AE patients as well as among patients with anti–NMDA receptor based on modified Rankin Scale (mRS) scores at the time of FDG-PET/CT. Results: The medial occipital lobes were markedly hypometabolic in 6 of 8 patients with anti–NMDA receptor encephalitis and as a group (Z = −4.02, interquartile range [IQR] 2.14) relative to those with definite AE (Z = −2.32, 1.46; p = 0.004). Among patients with anti–NMDA receptor encephalitis, the lateral and medial occipital lobes were markedly hypometabolic for patients with mRS 4–5 (lateral occipital lobe Z = −3.69, IQR 1; medial occipital lobe Z = −4.08, 1) compared with those with mRS 0–3 (lateral occipital lobe Z = −0.83, 2; p occipital lobe Z = −1.07, 2; p = 0.001). Conclusions: Marked medial occipital lobe hypometabolism by dedicated brain FDG-PET/CT may serve as an early biomarker for discriminating anti–NMDA receptor encephalitis from other AE. Resolution of lateral and medial occipital hypometabolism may correlate with improved neurologic status in anti–NMDA receptor encephalitis. PMID:29159205

  11. Ice recrystallization inhibition in ice cream by propylene glycol monostearate.

    Science.gov (United States)

    Aleong, J M; Frochot, S; Goff, H D

    2008-11-01

    The effectiveness of propylene glycol monostearate (PGMS) to inhibit ice recrystallization was evaluated in ice cream and frozen sucrose solutions. PGMS (0.3%) dramatically reduced ice crystal sizes in ice cream and in sucrose solutions frozen in a scraped-surface freezer before and after heat shock, but had no effect in quiescently frozen solutions. PGMS showed limited emulsifier properties by promoting smaller fat globule size distributions and enhanced partial coalescence in the mix and ice cream, respectively, but at a much lower level compared to conventional ice cream emulsifier. Low temperature scanning electron microscopy revealed highly irregular crystal morphology in both ice cream and sucrose solutions frozen in a scraped-surface freezer. There was strong evidence to suggest that PGMS directly interacts with ice crystals and interferes with normal surface propagation. Shear during freezing may be required for its distribution around the ice and sufficient surface coverage.

  12. El movimiento de los trabajadores rurales sin tierra y la reforma agraria en Brasil

    Directory of Open Access Journals (Sweden)

    Lorenzo FERNÁNDEZ FRANCO

    2009-11-01

    Full Text Available RESUMEN: Este artículo, es un primer avance, de carácter exploratorio, de una investigación más amplia que el autor está llevando a cabo sobre el mismo tema. Centrado en el "Movimiento de los Trabajadores Rurales sin Tierra", habitualmente identificado en Brasil por las siglas MST, se contempla dicho movimiento social desde sus orígenes más remotos, al final de los años 50, hasta nuestros días situándolo, por un lado, en las transformaciones políticas y en parte sociales, y en el largo y lento proceso de una reforma agraria inconclusa, por otro. De forma descriptiva, se desarrollan, en un primer paso, los antecedentes, proceso de constitución, etapas y estructura agraria brasileña, se plantea de forma suscinta la problemática de la reforma agraria. Con estas consideraciones preliminares, siguiendo casi literalmente la formulación del propio MST, se exponen, con mayor amplitud, los objetivos y características de la Reforma Agraria desde la perspectiva de los propios trabajadores rurales. Asimismo, aunque de forma más esquemática y en base a los datos oficiales, se plantean las directrices, metas y algunas de las realizaciones del Gobierno de Fernando H. Cardoso sobre dicha reforma. En definitiva, con este artículo, se pretenden establecer las bases y los ejes analíticos necesarios para una investigación más amplia y comprensiva de este fenómeno social de masas que va más allá de la propia realidad de injusticia que se está viviendo en el mundo rural brasileño y que está contando también con un amplio y sorprendente apoyo de sectores urbanos de la población brasileña.ABSTRACT: This article is an introductory and exploratory advance of a more extensive investigation that the author is carrying out on the same subject. The research is centred on the "Movement of the Rural Workers without Land", which is ussually identified in Brazil with the initials MST. This social movement is analyzed since its remotest origins, the

  13. Method for maintenance of ice beds of ice condenser containment

    International Nuclear Information System (INIS)

    Scrabis, C.M.; Hardin, R.T. Jr.

    1987-01-01

    This patent describes a method of maintaining ice baskets associated with a nuclear reactor system and disposed in an array of plural such ice baskets, supported in generally vertically oriented and parallel relationship by a lattice support structure which extends between the individual ice baskets and includes lateral supports adjacent the tops of the comprising: selecting an ice basket of the array requiring replenishment of the ice therewithin due to sublimation voids within the ice charges in the basket; isolating the selected ice basket; drilling a hole downwardly through the ice charges in the ice basket in general parallel axial relationship with respect to the cylindrical sidewall of the ice basket, utilizing a rotary drill bit connected through an auger to a rotary drive means; maintaining the rotary drive means in a fixed axial position and reversing the direction of rotation thereof for driving the auger in reverse rotation; and supplying ice in particulate form to the vicinity of the auger and conveying the particulate ice through the drilled hole by continued, reverse rotation of the auger so as to fill the sublimated voids in communication with the drilled hole, from the lowest and through successively higher such voids in the ice charges within the ice basket, and withdrawing the auger from the drilled hole as the voids are filled

  14. Giant lipoma arising from deep lobe of the parotid gland

    Directory of Open Access Journals (Sweden)

    Hsu Ying-Che

    2006-06-01

    Full Text Available Abstract Background Lipomas are common benign soft tissue neoplasms but they are found very rarely in the deep lobe of parotid gland. Surgical intervention in these tumors is challenging because of the proximity of the facial nerve, and thus knowledge of the anatomy and meticulous surgical technique are essential. Case presentation A 71-year-old female presented with a large asymptomatic mass, which had occupied the left facial area for over the past fifteen years, and she requested surgical excision for a cosmetically better facial appearance. The computed tomography (CT scan showed a well-defined giant lipoma arising from the left deep parotid gland. The lipoma was successfully enucleated after full exposure and mobilization of the overlying facial nerve branches. The surgical specimen measured 9 × 6 cm in size, and histopathology revealed fibrolipoma. The patient experienced an uneventful recovery, with a satisfying facial contour and intact facial nerve function. Conclusion Giant lipomas involving the deep parotid lobe are extremely rare. The high-resolution CT scan provides an accurate and cost-effective preoperative investigative method. Surgical management of deep lobe lipoma should be performed by experienced surgeons due to the need for meticulous dissection of the facial nerve branches. Superficial parotidectomy before deep lobe lipoma removal may be unnecessary in selected cases because preservation of the superficial lobe may contribute to a better aesthetic and functional result.

  15. Temporal order processing of syllables in the left parietal lobe.

    Science.gov (United States)

    Moser, Dana; Baker, Julie M; Sanchez, Carmen E; Rorden, Chris; Fridriksson, Julius

    2009-10-07

    Speech processing requires the temporal parsing of syllable order. Individuals suffering from posterior left hemisphere brain injury often exhibit temporal processing deficits as well as language deficits. Although the right posterior inferior parietal lobe has been implicated in temporal order judgments (TOJs) of visual information, there is limited evidence to support the role of the left inferior parietal lobe (IPL) in processing syllable order. The purpose of this study was to examine whether the left inferior parietal lobe is recruited during temporal order judgments of speech stimuli. Functional magnetic resonance imaging data were collected on 14 normal participants while they completed the following forced-choice tasks: (1) syllable order of multisyllabic pseudowords, (2) syllable identification of single syllables, and (3) gender identification of both multisyllabic and monosyllabic speech stimuli. Results revealed increased neural recruitment in the left inferior parietal lobe when participants made judgments about syllable order compared with both syllable identification and gender identification. These findings suggest that the left inferior parietal lobe plays an important role in processing syllable order and support the hypothesized role of this region as an interface between auditory speech and the articulatory code. Furthermore, a breakdown in this interface may explain some components of the speech deficits observed after posterior damage to the left hemisphere.

  16. Frontal lobe atrophy of the brain in schizophrenia

    International Nuclear Information System (INIS)

    Hara, Tomio

    1981-01-01

    Reported here are the CT findings on cerebral atrophic lesion chiefly developed in the frontal lobe in schizophrenics with unusual organic encephalopathy. Encephalopathy was recognized in 84 (73%) of 115 schizophrenics and 13 (33%) of 40 neurotics. In an attempt to exclude the effects of aging on encephalopathy, the ages at CT and at the development of disease, the number of morbid years, subtypical schizophrenia and relation between the clinical severity and the atrophic condition were comparatively studied. As a result, cerebral atrophy tended to increase along with aging, but the findings differed in that atrophia classified by age covered the entire brain in general, whereas atrophia in schizophrenics was found in the frontal lobe. In particular, because of the fact that clinical severity and atrophia in the frontal lobe are high correlated and that severe atrophia is recognized even in young people, schizophrenia and atrophia in the frontal lobe are considered to be closely related to each other. It is therefore suggested that the CT findings are useful to clinicians for finding appropriate methods to deal with the prognosis of schizophrenics in their daily diagnosis and for the therapeutic prevention of encephalatrophy by stimulating the frontal lobe, thereby delaying mental deterioration. (author)

  17. Seizure semiology identifies patients with bilateral temporal lobe epilepsy.

    Science.gov (United States)

    Loesch, Anna Mira; Feddersen, Berend; Tezer, F Irsel; Hartl, Elisabeth; Rémi, Jan; Vollmar, Christian; Noachtar, Soheyl

    2015-01-01

    Laterality in temporal lobe epilepsy is usually defined by EEG and imaging results. We investigated whether the analysis of seizure semiology including lateralizing seizure phenomena identifies bilateral independent temporal lobe seizure onset. We investigated the seizure semiology in 17 patients in whom invasive EEG-video-monitoring documented bilateral temporal seizure onset. The results were compared to 20 left and 20 right consecutive temporal lobe epilepsy (TLE) patients who were seizure free after anterior temporal lobe resection. The seizure semiology was analyzed using the semiological seizure classification with particular emphasis on the sequence of seizure phenomena over time and lateralizing seizure phenomena. Statistical analysis included chi-square test or Fisher's exact test. Bitemporal lobe epilepsy patients had more frequently different seizure semiology (100% vs. 40%; p<0.001) and significantly more often lateralizing seizure phenomena pointing to bilateral seizure onset compared to patients with unilateral TLE (67% vs. 11%; p<0.001). The sensitivity of identical vs. different seizure semiology for the identification of bilateral TLE was high (100%) with a specificity of 60%. Lateralizing seizure phenomena had a low sensitivity (59%) but a high specificity (89%). The combination of lateralizing seizure phenomena and different seizure semiology showed a high specificity (94%) but a low sensitivity (59%). The analysis of seizure semiology including lateralizing seizure phenomena adds important clinical information to identify patients with bilateral TLE. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Epilepsy in multiple sclerosis: The role of temporal lobe damage.

    Science.gov (United States)

    Calabrese, M; Castellaro, M; Bertoldo, A; De Luca, A; Pizzini, F B; Ricciardi, G K; Pitteri, M; Zimatore, S; Magliozzi, R; Benedetti, M D; Manganotti, P; Montemezzi, S; Reynolds, R; Gajofatto, A; Monaco, S

    2017-03-01

    Although temporal lobe pathology may explain some of the symptoms of multiple sclerosis (MS), its role in the pathogenesis of seizures has not been clarified yet. To investigate the role of temporal lobe damage in MS patients suffering from epilepsy, by the application of advanced multimodal 3T magnetic resonance imaging (MRI) analysis. A total of 23 relapsing remitting MS patients who had epileptic seizures (RRMS/E) and 23 disease duration matched RRMS patients without any history of seizures were enrolled. Each patient underwent advanced 3T MRI protocol specifically conceived to evaluate grey matter (GM) damage. This includes grey matter lesions (GMLs) identification, evaluation of regional cortical thickness and indices derived from the Neurite Orientation Dispersion and Density Imaging model. Regional analysis revealed that in RRMS/E, the regions most affected by GMLs were the hippocampus (14.2%), the lateral temporal lobe (13.5%), the cingulate (10.0%) and the insula (8.4%). Cortical thinning and alteration of diffusion metrics were observed in several regions of temporal lobe, in insular cortex and in cingulate gyrus of RRMS/E compared to RRMS ( ptemporal lobe, which exceeds what would be expected on the basis of the global GM damage observed.

  19. Quantifying interictal metabolic activity in human temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Henry, T.R.; Mazziotta, J.C.; Engel, J. Jr.; Christenson, P.D.; Zhang, J.X.; Phelps, M.E.; Kuhl, D.E.

    1990-01-01

    The majority of patients with complex partial seizures of unilateral temporal lobe origin have interictal temporal hypometabolism on [18F]fluorodeoxyglucose positron emission tomography (FDG PET) studies. Often, this hypometabolism extends to ipsilateral extratemporal sites. The use of accurately quantified metabolic data has been limited by the absence of an equally reliable method of anatomical analysis of PET images. We developed a standardized method for visual placement of anatomically configured regions of interest on FDG PET studies, which is particularly adapted to the widespread, asymmetric, and often severe interictal metabolic alterations of temporal lobe epilepsy. This method was applied by a single investigator, who was blind to the identity of subjects, to 10 normal control and 25 interictal temporal lobe epilepsy studies. All subjects had normal brain anatomical volumes on structural neuroimaging studies. The results demonstrate ipsilateral thalamic and temporal lobe involvement in the interictal hypometabolism of unilateral temporal lobe epilepsy. Ipsilateral frontal, parietal, and basal ganglial metabolism is also reduced, although not as markedly as is temporal and thalamic metabolism

  20. Use of explicit memory cues following parietal lobe lesions.

    Science.gov (United States)

    Dobbins, Ian G; Jaeger, Antonio; Studer, Bettina; Simons, Jon S

    2012-11-01

    The putative role of the lateral parietal lobe in episodic memory has recently become a topic of considerable debate, owing primarily to its consistent activation for studied materials during functional magnetic resonance imaging studies of recognition. Here we examined the performance of patients with parietal lobe lesions using an explicit memory cueing task in which probabilistic cues ("Likely Old" or "Likely New"; 75% validity) preceded the majority of verbal recognition memory probes. Without cues, patients and control participants did not differ in accuracy. However, group differences emerged during the "Likely New" cue condition with controls responding more accurately than parietal patients when these cues were valid (preceding new materials) and trending towards less accuracy when these cues were invalid (preceding old materials). Both effects suggest insufficient integration of external cues into memory judgments on the part of the parietal patients whose cued performance largely resembled performance in the complete absence of cues. Comparison of the parietal patients to a patient group with frontal lobe lesions suggested the pattern was specific to parietal and adjacent area lesions. Overall, the data indicate that parietal lobe patients fail to appropriately incorporate external cues of novelty into recognition attributions. This finding supports a role for the lateral parietal lobe in the adaptive biasing of memory judgments through the integration of external cues and internal memory evidence. We outline the importance of such adaptive biasing through consideration of basic signal detection predictions regarding maximum possible accuracy with and without informative environmental cues. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Case Report: A Rare Case Report of Frontal Lobe Syndrome

    Directory of Open Access Journals (Sweden)

    Morteza Nouri- Khajavi

    2003-04-01

    Full Text Available The frontal lobe syndrome is a permanent personality change disorder with characteristic clinical pictures, which followed by frontal lobes damage. Clinical picture include: Affective instability, recurrent aggressive behavior, impaired social judgment, apathy and undifferentiating or suspiciousness and paranoid ideations. According DSM-IV classification frontal lobe syndrome named personality change due to head trauma on Axis I. Herein we report a case of 46 years-old man, who has developed behavioral disturbances following head trauma, about 10 years ago. Main clinical figures in this case are apathy, avolition and, undifferentiating. Clinical pictures are constant during these 10 years. The diagnostic approach has been based on patient’s problems history which, has taken from his family, mental status examination, Neurological examination, Brain imaging and Neuropsychological assessments which related to frontal lobes function. Because of rarity & neglection due to mysterious function of frontal lobes, and also considering that personality change from previous level is prominent figure of this syndrome and also brain imaging findings, which compatible with clinical findings, with this aim, we have reported this case.

  2. LA MOVILIZACIÓN DE LOS GARÍFUNAS PARA PRESERVAR SUS TIERRAS «ANCESTRALES» EN GUATEMALA

    OpenAIRE

    Nicolás Rey

    2009-01-01

    Livingston, en el noreste de Guatemala, es la «ciudad negra» de ese país que cuenta con una población de mayoría maya. Los derechos de los garífunas, mayas y xincas —recuperación de tierras ancestrales, valorización de su identidad y desarrollo socioeconómico— fueron inscritos en los Acuerdos de Paz, 1995-1996. Este artículo, resultado de una amplia investigación, presenta la increíble trayectoria de los garífunas: - un pueblo «en resistencia» nacido en las Antillas Menores, del encuentr...

  3. La tierra urbana en el portafolio de las fortunas antioqueñas en la primera mitad del siglo XX

    Directory of Open Access Journals (Sweden)

    Fernando Botero

    1992-07-01

    Full Text Available La tesis principal, motivo de debate abierto que se plantea con este ensayo, tiene que ver con el papel que la tierra urbana tuvo en el conjunto de las fortunas antioqueñas. A su vez, esta temática sirve como puente para conectar los negocios a la historia urbana y ayudar a iluminar el debate en torno a la acumulación de capital en Antioquia. De esta forma la polémica sirve como pretexto y telón de fondo para exponer algunas tesis alternativas y proponer una nueva ventana para leer nuestro pasado y recuperar la memoria perdida que constituye el gran potencial y la esperanza para construir nuestro futuro.

  4. Identifying potential differences in ontogentic ages between modern and archaeological Nacella deaurata shells, Tierra del Fuego, Argentina

    Science.gov (United States)

    Surge, D. M.; Godino, I. B. I.; Álvarez, M.; López, M. B. I.

    2017-12-01

    Patelloid limpet shells are common constituents of rocky shore habitats along the eastern Atlantic basin and are often found in archaeological shell middens. Nacella deaurata is an intertidal species found in the Magellanic Province along the southern tip of South America. Recent discoveries of archaeological shell middens in Tierra del Fuego, Argentina, identify N. deaurata as one of the abundant shells in these deposits. Preliminary observations reveal that modern N. deaurata shells achieve larger sizes compared to those found in the archaeological middens. Here, we provide preliminary data to test the hypothesis that the larger, modern specimens grow to older ontogenetic ages than the smaller archaeological specimens. Our results may provide insights into harvesting pressures on this species during the time when the archaeological sites were inhabited. Understanding their annual growth patterns also has important implications for generating oxygen isotope proxy data to reconstruct seasonal variation in sea surface temperature.

  5. El acaparamiento de las tierras a gran escala en el mundo. El papel de las firmas multinacionales (Internacional)

    OpenAIRE

    Perdriault, Mathieu

    2011-01-01

    En los años 2007 y 2008, los medios de comunicación se hicieron eco, de manera creciente, de la adquisición –por intereses públicos o privados–, de los derechos de propiedad sobre grandes extensiones de tierra, especialmente en África, América y Europa del Este. Los miembros de la ONG GRAIN están entre los primeros que han observado la proliferación de artículos de prensa sobre este tema. Se los presentó ante los ojos de la opinión pública mundial, en octubre del 2008, mediante una recopilac...

  6. Effect of resource spatial correlation and hunter-fisher-gatherer mobility on social cooperation in Tierra del Fuego.

    Directory of Open Access Journals (Sweden)

    José Ignacio Santos

    Full Text Available This article presents an agent-based model designed to explore the development of cooperation in hunter-fisher-gatherer societies that face a dilemma of sharing an unpredictable resource that is randomly distributed in space. The model is a stylised abstraction of the Yamana society, which inhabited the channels and islands of the southernmost part of Tierra del Fuego (Argentina-Chile. According to ethnographic sources, the Yamana developed cooperative behaviour supported by an indirect reciprocity mechanism: whenever someone found an extraordinary confluence of resources, such as a beached whale, they would use smoke signals to announce their find, bringing people together to share food and exchange different types of social capital. The model provides insight on how the spatial concentration of beachings and agents' movements in the space can influence cooperation. We conclude that the emergence of informal and dynamic communities that operate as a vigilance network preserves cooperation and makes defection very costly.

  7. Icing losses on wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, T.; Fotsing, I.; Pearson, S. [Garrad Hassan Canada Inc., Ottawa, ON (Canada)

    2010-07-01

    This PowerPoint presentation discussed some of the energy losses that can occur as a result of icing on wind turbines. Airfoil deterioration can occur in the presence of rime and glaze ice. Anemometers are also impacted by ice, and shut-downs can occur as a result of icing events. Availability deficits that occur during the winter months can lead to annual energy losses of 0.5 percent. The impact of icing events on total wind power energy production in Quebec is estimated at between 1.3 percent to 2.7 percent. Ice loss estimates are considered during the pre-construction phases of wind power projects. However, ice loss prediction methods are often inaccurate. Studies have demonstrated that preconstruction masts show a reasonable correlation with wind turbine icing, and that icing losses are site-specific. tabs., figs.

  8. El Hidróxido de Calcio y los bloques de tierra comprimida, alternativa sostenible de construcción

    Directory of Open Access Journals (Sweden)

    Rubén Salvador Roux Gutiérrez

    2012-01-01

    Full Text Available En la actualidad, en nuestro país se hace mención a que existen una serie de problemas con los programas de vivienda, aún cuando se ha reducido el déficit de vivienda o que se han construido c ada año más viviendas en beneficio de las personas de bajos ingresos. Topelson (2011 el presente artículo describe un estudio sobre una alternativa sustentable de edificación y a la vez pretende demostrar las ventajas del uso del hidróxido de cal y los bl oques de tierra comprimida (BTC, para la edificación de vivienda y así poder reducir las emisones de CO 2 emitidas por los procesos constructivos convenci o nales El presente artículo trata dos materiales elementales en los procesos constructivos de las viv iendas, por un lado se realizá el estudio químico de los morteros cal – arena que se utilizán para el pegado de los mampuestos y los revoques, con la finalidad de determinar la absorción de CO 2 y por otra parte se hace el estudio mecánicos de un materia l alternativo para el uso de muros de carga como son los Bloques de Tierra Comprimida estabilizados con cal, por último se hace un comparativo entre estos materiales alternativos y los convencionales con relación a las emisones de CO2.

  9. Estado y territorio: aportes, desafíos y tensiones en torno a los problemas de tierra en San Juan

    Directory of Open Access Journals (Sweden)

    Margarita Moscheni Bustos

    2015-06-01

    Full Text Available RESUMEN La disputa por la tierra se ha convertido en un tema relevante para la política argentina en el siglo XX. Poseedores históricos, propietarios y desposeídos son los actores que participan en la trama. Atravesando el juego, se encuentra el Estado en sus distintos niveles, que con cierta autonomía relativa, regula a favor de unos y en detrimento de otros. Este trabajo se propone aportar datos empíricos sobre algunas tensiones territoriales en la provincia de San Juan y el rol del Estado y sus contradicciones en los distintos niveles. El caso gira en torno a la disputa por la tierra, generando tensiones políticas entre propiedad privada y propiedad comunitaria, o entre el derecho civil y los derechos emanados de la Constitución Nacional, los Tratados Internacionales y la Ley de Bosques Nativos N° 26.331. ABSTRACT The fight about lands has been became in a relevant situation for the argentine politics in the 20th century, the historic owners, and dispossessed are the most important actors. The state through its different levels has a certain kind of autonomy and regulate and take actions which tend to favor some social groups and damage others. In this work is proposed give some empirical facts about territorial tensions in the province of San Juan, its role and contradictions in its different levels. The case revolves around the land dispute, generating political tensions between private property and communal property, or between civil law and rights arising out of the National Constitution, international treaties and Native Forest Law, No. 26.331.

  10. [Distribution patterns of canopy and understory tree species at local scale in a Tierra Firme forest, the Colombian Amazonia].

    Science.gov (United States)

    Barreto-Silva, Juan Sebastian; López, Dairon Cárdenas; Montoya, Alvaro Javier Duque

    2014-03-01

    The effect of environmental variation on the structure of tree communities in tropical forests is still under debate. There is evidence that in landscapes like Tierra Firme forest, where the environmental gradient decreases at a local level, the effect of soil on the distribution patterns of plant species is minimal, happens to be random or is due to biological processes. In contrast, in studies with different kinds of plants from tropical forests, a greater effect on floristic composition of varying soil and topography has been reported. To assess this, the current study was carried out in a permanent plot of ten hectares in the Amacayacu National Park, Colombian Amazonia. To run the analysis, floristic and environmental variations were obtained according to tree species abundance categories and growth forms. In order to quantify the role played by both environmental filtering and dispersal limitation, the variation of the spatial configuration was included. We used Detrended Correspondence Analysis and Canonical Correspondence Analysis, followed by a variation partitioning, to analyze the species distribution patterns. The spatial template was evaluated using the Principal Coordinates of Neighbor Matrix method. We recorded 14 074 individuals from 1 053 species and 80 families. The most abundant families were Myristicaceae, Moraceae, Meliaceae, Arecaceae and Lecythidaceae, coinciding with other studies from Northwest Amazonia. Beta diversity was relatively low within the plot. Soils were very poor, had high aluminum concentration and were predominantly clayey. The floristic differences explained along the ten hectares plot were mainly associated to biological processes, such as dispersal limitation. The largest proportion of community variation in our dataset was unexplained by either environmental or spatial data. In conclusion, these results support random processes as the major drivers of the spatial variation of tree species at a local scale on Tierra Firme

  11. Un suelo referible al periodo calido medieval en Patagonia Austral y Tierra del Fuego (Argentina. Aspectos cronologicos y paleoclimaticos

    Directory of Open Access Journals (Sweden)

    Favier Dubois, C. M.

    2002-08-01

    Full Text Available Geoarchaeological work done in Southernmost Patagonia and in the north of Tierra del Fuego, have revealed the recurrent presence of a paedogenesis interval represented by a soil of an A-AC-C profile, with a mollic epipedon, in the upper section of eolian and colluvial deposits of the late Holocene. This soil is today buried in the sites that have been analyzed, while it remains exposed in other areas of the landscape. Radiocarbon dates obtained on materials placed below it (maximum ages and those obtained by OCR (Oxidizable Carbon Ratio in the AC horizon of this soil (minimum ages, indicate the beginning of its development around the year 1000 BP. Its chronology and environmental implications suggest a relationship with the medieval climatic fluctuations called Medieval Warm Period or Medieval Optimum in Europe. This period has correlates detected in Patagonia by dendroclimatic studies.Estudios geoarqueológicos realizados en 5 localidades de Patagonia austral y norte Tierra del Fuego han revelado la recurrente presencia de un suelo de perfil A-AC-C, de epipedon mólico, en depósitos eólicos y coluviales del Holoceno tardío. Este suelo se observa sepultado en los yacimientos arqueológicos analizados, mientras que permanece expuesto en otras posiciones del paisaje. Numerosas edades máximas y mínimas obtenidas por 14C y por la técnica de OCR (Oxidizable Carbon Ratio indican el comienzo de su desarrollo hacia el 1000 AP. Su cronología e implicancias ambientales permiten vincularlo con fluctuaciones climáticas desarrolladas durante el denominado Período Cálido Medieval u Optimo Medieval Europeo, con correlatos detectados en Patagonia a través de estudios dendroclimáticos.

  12. Inferencias paleodietarias mediante isótopos estables en restos óseos humanos provenientes de Tierra del Fuego, Argentina

    Directory of Open Access Journals (Sweden)

    Schinder, Gala

    2003-01-01

    Full Text Available Las actuales lineas de acción vinculadas al uso de isótopos estables en la Isla Grande de Tierra del Fuego están orientándose a acotar factores de variación (especialmente la variación espacial y temporal y al cruce con otras lineas de evidencias como los estilos de vida. A partir de la ocupación europea en el Siglo XVIII se modificó el estilo de vida de las poblaciones históricas de la región. El presente trabajo tiene como objetivos explorar la variabilidad en cuanto al tipo de recursos consurnidos por hombres y mujeres a partir de la información isotópica obtenida de huesos de individuos provenientes de diferentes sectores geográficos (Norte, Sudeste y Beagle y la determinación de la composición de la dieta en términos de contenido proteico. Los datos isotópicos se complementaron con información etnográfica. El análisis Kruskal-Wallis sugiere que existen diferencias significativas entre los diferentes sectores geográficos, pero no se registraron diferencias significativas entre hombres y mujeres. Asimismo, los isótopos indican que los individuos del Sudeste consumían preferentemente dietas más ricas en proteínas que sus vecinos del norte de la Isla. En los últimos años, ha crecido el interé por los estudios orientados al análisis de la división sexual del trabajo en sociedades cazadoras recolectoras. Este trabajo constituye un primer aporte para evaluar la variabilidad en cuanto a las diferencias en la obtención de recursos entre sexos y el tipo de dieta en individuos históricos de Tierra del Fuego.

  13. Ice flow Modelling of the Greenland Ice Sheet

    DEFF Research Database (Denmark)

    Nielsen, Lisbeth Tangaa

    Models of ice flow have a range of application in glaciology, including investigating the large-scale response of ice sheets to changes in climate, assimilating data to estimate unknown conditions beneath the ice sheet, and in interpreting proxy records obtained from ice cores, among others. In t...... a steady state with respect to the reference climate at the end of the simulation and that the mass balance of the ice sheet at this time was more sensitive to recent climate fluctuations than the temperature forcing in the early or mid-Holocene.......Models of ice flow have a range of application in glaciology, including investigating the large-scale response of ice sheets to changes in climate, assimilating data to estimate unknown conditions beneath the ice sheet, and in interpreting proxy records obtained from ice cores, among others....... In this PhD project, the use of ice flow models for the interpretation of the age-structure of the Greenland ice sheet, i.e. the depth within the ice, at which ice deposited at given times are found at present day. Two different observational data sets of this archive were investigated. Further, paleo...

  14. Modeling Commercial Turbofan Engine Icing Risk With Ice Crystal Ingestion

    Science.gov (United States)

    Jorgenson, Philip C. E.; Veres, Joseph P.

    2013-01-01

    The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which are ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in

  15. Usefulness of PET in non-lesional temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Bertuluchi, M.; Arganaraz, R.; Buznick, J.; Pomata, H.

    2011-01-01

    Objective. To evaluate the usefulness of PET in patients with refractory non-lesional temporal lobe epilepsy. Material and methods. We present three patients with features of temporal lobe epilepsy refractory to medication, where high definition MRI was normal. Results. These patients had PET hypometabolism in the temporal areas related to clinical and neurophysiological findings. Two of these patients were implanted with subdural grids to confirm the diagnosis and the third was operated directly based on the findings of PET. Encourage the presentation of the importance in recent years is acquiring the PET. Conclusion. In those patients in clinical neurophysiology and epilepsy with suspected temporal lobe, but in the MRI images show no structural lesions, PET can play an important role defining the diagnosis. (authors)

  16. Altered cortical anatomical networks in temporal lobe epilepsy

    Science.gov (United States)

    Lv, Bin; He, Huiguang; Lu, Jingjing; Li, Wenjing; Dai, Dai; Li, Meng; Jin, Zhengyu

    2011-03-01

    Temporal lobe epilepsy (TLE) is one of the most common epilepsy syndromes with focal seizures generated in the left or right temporal lobes. With the magnetic resonance imaging (MRI), many evidences have demonstrated that the abnormalities in hippocampal volume and the distributed atrophies in cortical cortex. However, few studies have investigated if TLE patients have the alternation in the structural networks. In the present study, we used the cortical thickness to establish the morphological connectivity networks, and investigated the network properties using the graph theoretical methods. We found that all the morphological networks exhibited the small-world efficiency in left TLE, right TLE and normal groups. And the betweenness centrality analysis revealed that there were statistical inter-group differences in the right uncus region. Since the right uncus located at the right temporal lobe, these preliminary evidences may suggest that there are topological alternations of the cortical anatomical networks in TLE, especially for the right TLE.

  17. Atypical language representation in children with intractable temporal lobe epilepsy.

    Science.gov (United States)

    Maulisova, Alice; Korman, Brandon; Rey, Gustavo; Bernal, Byron; Duchowny, Michael; Niederlova, Marketa; Krsek, Pavel; Novak, Vilem

    2016-05-01

    This study evaluated language organization in children with intractable epilepsy caused by temporal lobe focal cortical dysplasia (FCD) alone or dual pathology (temporal lobe FCD and hippocampal sclerosis, HS). We analyzed clinical, neurological, fMRI, neuropsychological, and histopathologic data in 46 pediatric patients with temporal lobe lesions who underwent excisional epilepsy surgery. The frequency of atypical language representation was similar in both groups, but children with dual pathology were more likely to be left-handed. Atypical receptive language cortex correlated with lower intellectual capacity, verbal abstract conceptualization, receptive language abilities, verbal working memory, and a history of status epilepticus but did not correlate with higher seizure frequency or early seizure onset. Histopathologic substrate had only a minor influence on neuropsychological status. Greater verbal comprehension deficits were noted in children with atypical receptive language representation, a risk factor for cognitive morbidity. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. A case of luftsichel sign for left upper lobe collapse

    Directory of Open Access Journals (Sweden)

    Erden Erol Ünlüer

    2015-01-01

    Full Text Available The differential diagnosis of dyspnea in Emergency Department (ED patients is broad and atelectasis is one of the differentials among these. We present a 29-year-old women presented to our ED for evaluation of shortness of breath. On her chest examination, air entry and breath sounds were diminished on the left side but normal on the right. A posteroanterior chest radiograph showed radioluscent area in the upper zone of the left lung, around the aortic arch and also hyperdens area neighbouring this, like covered by a veil. Luftsichel sign together with this hiperdensity were consistent with the diagnose of left lung upper lobe collapse. The Luftsichel sign represents the hyperexpanded superior segment of the left lower lobe interposed between the atelectatic left upper lobe and aortic arch. Patient was discharged to home with chest physiotherapy and breathing exercises together with analgesic prescreption.

  19. Late bilateral temporal lobe necrosis after conventional radiotherapy. Case report

    Energy Technology Data Exchange (ETDEWEB)

    Hoshi, Michio; Hayashi, Toshiyuki; Kagami, Hiroshi; Murase, Ikurou; Nakatsukasa, Masashi [Saiseikai Utsunomiya Hospital (Japan)

    2003-04-01

    A 63-year-old woman presented with radionecrosis in the bilateral temporal lobes manifesting as dementia about 30 years after undergoing conventional radiotherapy for pituitary adenoma. Computed tomography and magnetic resonance (MR) imaging showed edema and cystic lesions in both temporal lobes. The mass in the left temporal lobe was excised. MR imaging 12 days after surgery showed reduced edema. Her dementia had improved. Radionecrosis usually occurs between several months and a few years after radiotherapy. The incidence of radionecrosis is estimated as 5%, but may be higher with longer follow-up periods. Clinical reports have suggested that larger total doses of radiation are associated with earlier onset of delayed necrosis and the fractional dose is the most significant factor causing cerebral radionecrosis. Radionecrosis can occur long after conventional radiotherapy or stereotactic radiosurgery using a linac-based system or a gamma knife unit. (author)

  20. Papillary thyroid microcarcinoma in a thyroid pyramidal lobe

    Directory of Open Access Journals (Sweden)

    Tae Kwun Ha

    2014-10-01

    Full Text Available

    We report an extremely rare case of papillary thyroid microcarcinoma (PTMC in the thyroid Epub ahead of print pyramidal lobe (TPL. A 48-year-old woman underwent ultrasound-guided fine-needle aspiration for a small thyroid nodule in the right lobe in local clinic, and it revealed a malignant cytology. On preoperative ultrasonography for tumor staging in our hospital, another small suspiciously malignant hypoechoic nodule was detected in the left TPL. Total thyroidectomy and central nodal dissection were performed. Histopathology confirmed PTMCs in the left TPL and both thyroid lobes. Ultrasonography for TPL should be required for complete evaluation of possible multifocality of thyroid malignancy.

  1. The ICES system

    International Nuclear Information System (INIS)

    Inzaghi, A.

    1983-01-01

    ICES is an integrated system used in the various engineering fields. It is made up of the Basic System and the applied Subsystems. ICES is controlled by the Operating System of the computer, from which it calls for suitable services: space allocation, loading of the modules etc... To be able to use software of this type on a computer the Operating System should be made more general. The Subsystems are developed with special programs included in the ICES Basic System. Each Subsystem is associated with an area of application. In other words, a Subsystem can only treat a previously defined ''class of problems''. The engineer (user) communicates with the Subsystem using a language oriented towards the problem (POL) also previously defined using the CDL language. The use of the (POL) language makes the engineer-computer contact much easier. The applied programs written in ICETRAN, once supplied as input to the ICETRAN Precompiler, become Fortran programs with special characteristics. A Fortran compiler produces the corresponding object programs with which, using the ICES ''Link-edit'' procedures, one obtains the modules which can be executed by an ICES Subsystem

  2. Astrocyte uncoupling as a cause of human temporal lobe epilepsy.

    Science.gov (United States)

    Bedner, Peter; Dupper, Alexander; Hüttmann, Kerstin; Müller, Julia; Herde, Michel K; Dublin, Pavel; Deshpande, Tushar; Schramm, Johannes; Häussler, Ute; Haas, Carola A; Henneberger, Christian; Theis, Martin; Steinhäuser, Christian

    2015-05-01

    Glial cells are now recognized as active communication partners in the central nervous system, and this new perspective has rekindled the question of their role in pathology. In the present study we analysed functional properties of astrocytes in hippocampal specimens from patients with mesial temporal lobe epilepsy without (n = 44) and with sclerosis (n = 75) combining patch clamp recording, K(+) concentration analysis, electroencephalography/video-monitoring, and fate mapping analysis. We found that the hippocampus of patients with mesial temporal lobe epilepsy with sclerosis is completely devoid of bona fide astrocytes and gap junction coupling, whereas coupled astrocytes were abundantly present in non-sclerotic specimens. To decide whether these glial changes represent cause or effect of mesial temporal lobe epilepsy with sclerosis, we developed a mouse model that reproduced key features of human mesial temporal lobe epilepsy with sclerosis. In this model, uncoupling impaired K(+) buffering and temporally preceded apoptotic neuronal death and the generation of spontaneous seizures. Uncoupling was induced through intraperitoneal injection of lipopolysaccharide, prevented in Toll-like receptor4 knockout mice and reproduced in situ through acute cytokine or lipopolysaccharide incubation. Fate mapping confirmed that in the course of mesial temporal lobe epilepsy with sclerosis, astrocytes acquire an atypical functional phenotype and lose coupling. These data suggest that astrocyte dysfunction might be a prime cause of mesial temporal lobe epilepsy with sclerosis and identify novel targets for anti-epileptogenic therapeutic intervention. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Determinants of brain metabolism changes in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Chassoux, Francine; Artiges, Eric; Semah, Franck; Desarnaud, Serge; Laurent, Agathe; Landre, Elisabeth; Gervais, Philippe; Devaux, Bertrand; Helal, Ourkia Badia

    2016-06-01

    To determine the main factors influencing metabolic changes in mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis (HS). We prospectively studied 114 patients with MTLE (62 female; 60 left HS; 15- to 56-year-olds) with (18) F-fluorodeoxyglucose-positron emission tomography and correlated the results with the side of HS, structural atrophy, electroclinical features, gender, age at onset, epilepsy duration, and seizure frequency. Imaging processing was performed using statistical parametric mapping. Ipsilateral hypometabolism involved temporal (mesial structures, pole, and lateral cortex) and extratemporal areas including the insula, frontal lobe, perisylvian regions, and thalamus, more extensively in right HS (RHS). A relative increase of metabolism (hypermetabolism) was found in the nonepileptic temporal lobe and in posterior areas bilaterally. Voxel-based morphometry detected unilateral hippocampus atrophy and gray matter concentration decrease in both frontal lobes, more extensively in left HS (LHS). Regardless of the structural alterations, the topography of hypometabolism correlated strongly with the extent of epileptic networks (mesial, anterior-mesiolateral, widespread mesiolateral, and bitemporal according to the ictal spread), which were larger in RHS. Notably, widespread perisylvian and bitemporal hypometabolism was found only in RHS. Mirror hypermetabolism was grossly proportional to the hypometabolic areas, coinciding partly with the default mode network. Gender-related effect was significant mainly in the contralateral frontal lobe, in which metabolism was higher in female patients. Epilepsy duration correlated with the contralateral temporal metabolism, positively in LHS and negatively in RHS. Opposite results were found with age at onset. High seizure frequency correlated negatively with the contralateral metabolism in LHS. Epileptic networks, as assessed by electroclinical correlations, appear to be the main determinant of

  4. Ice Engineering. Number 25, September 2000. Remote Ice Motion Detection

    National Research Council Canada - National Science Library

    2000-01-01

    .... Government agencies, and the engineering community in general. The potential exists for property damage, serious injury, and fatalities during ice-related flooding, evacuations, and other ice mitigation operations...

  5. Early seizure propagation from the occipital lobe to medial temporal structures and its surgical implication.

    Science.gov (United States)

    Usui, Naotaka; Mihara, Tadahiro; Baba, Koichi; Matsuda, Kazumi; Tottori, Takayasu; Umeoka, Shuichi; Nakamura, Fumihiro; Terada, Kiyohito; Usui, Keiko; Inoue, Yushi

    2008-12-01

    Intracranial EEG documentation of seizure propagation from the occipital lobe to medial temporal structures is relatively rare. We retrospectively analyzed intracranial EEG recorded with electrodes implanted in the medial temporal lobe in patients who underwent occipital lobe surgery. Four patients with occipital lesions, who underwent intracranial EEG monitoring with intracerebral electrodes implanted in the medial temporal lobe prior to occipital lobe surgery, were studied. Subdural electrodes were placed over the occipital lobe and adjacent areas. Intracerebral electrodes were implanted into bilateral hippocampi and the amygdala in three patients, and in the hippocampus and amygdala ipsilateral to the lesion in one. In light of the intracranial EEG findings, the occipital lobe was resected but the medial temporal lobe was spared in all patients. The follow-up period ranged from six to 16 years, and seizure outcome was Engel Class I in all patients. Sixty six seizures were analyzed. The majority of the seizures originated from the occipital lobe. In complex partial seizures, ictal discharges propagated to the medial temporal lobe. No seizures originating from the temporal lobe were documented. In some seizures, the ictal-onset zone could not be identified. In these seizures, very early propagation to the medial temporal lobe was observed. Interictal spikes were recorded in the medial temporal lobe in all cases. Intracranial EEG revealed very early involvement of the medial temporal lobe in some seizures. Seizure control was achieved without resection of the medial temporal structures.

  6. Transient response of two lobe aerodynamic journal bearing

    Directory of Open Access Journals (Sweden)

    Saurabh Kumar Yadav

    2018-03-01

    Full Text Available The dynamic behavior of a rotor-dynamic system is greatly affected by the performance of aerodynamic bearing and the performance of bearing is characterized by the stiffness and damping coefficients. In the present work, stiffness and damping coefficients of bearing are computed and the performance of the bearing is greatly changed with the change in bearing air film profile. The effect of lobe offset factors on the transient performance of aerodynamic bearing is presented. Bifurcation and Poincare diagrams of two lobe journal bearing have been presented for different offset factors. A bearing designer can judge the bearing performance based on bifurcation diagrams.

  7. A case of viral encephalitis localized in the occipital lobe

    International Nuclear Information System (INIS)

    Izawa, Masahiro; Okino, Teruhiko; Kagawa, Mizuo; Kitamura, Koichi.

    1987-01-01

    A case is reported of a 63-year-old female admitted to our hospital in Oct., 1986, with complaints of headache and visual field disturbance. A plain CT scan showed no abnormal low-density focal area. A contrast-enhancement CT scan, however, showed a localized linear abnormal enhancement in the right occipital lobe, without any mass-effect. A dynamic CT scan demonstrated a hyperemic perfusion pattern of the right occipital lobe. A visual-field examination showed left homonymous hemianopsia with concentric narrowing. These abnormal findings on CT, EEG, and ophthalmological examination disappeared within 3 weeks. (author)

  8. Visual field defects after temporal lobe resection for epilepsy

    DEFF Research Database (Denmark)

    Steensberg, Alvilda T; Olsen, Ane Sophie; Litman, Minna

    2018-01-01

    PURPOSE: To determine visual field defects (VFDs) using methods of varying complexity and compare results with subjective symptoms in a population of newly operated temporal lobe epilepsy patients. METHODS: Forty patients were included in the study. Two patients failed to perform VFD testing...... symptoms were only reported by 28% of the patients with a VFD and in two of eight (sensitivity=25%) with a severe VFD. Most patients (86%) considered VFD information mandatory. CONCLUSION: VFD continue to be a frequent adverse event after epilepsy surgery in the medial temporal lobe and may affect...

  9. Preoperative visual field deficits in temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Sanjeet S. Grewal

    2017-01-01

    Full Text Available Surgical resection and laser thermoablation have been used to treat drug resistant epilepsy with good results. However, they are not without risk. One of the most commonly reported complications of temporal lobe surgery is contralateral superior homonymous quadrantanopsia. We describe a patient with asymptomatic preoperative quadrantanopsia fortuitously discovered as part of our recently modified protocol to evaluate patients prior to temporal lobe epilepsy surgery. This visual field deficit was subtle and not detected on routine clinical neurological examination. While we understand that this is a single case, we advocate further study for more detailed preoperative visual field examinations to characterize the true incidence of postoperative visual field lesions.

  10. Radiosurgery in the Management of Intractable Mesial Temporal Lobe Epilepsy.

    Science.gov (United States)

    Peñagarícano, José; Serletis, Demitre

    2015-09-01

    Mesial temporal lobe epilepsy (MTLE) describes recurrent seizure activity originating from the depths of the temporal lobe. MTLE patients who fail two trials of medication now require testing for surgical candidacy at an epilepsy center. For these individuals, temporal lobectomy offers the greatest likelihood for seizure-freedom (up to 80-90%); unfortunately, this procedure remains largely underutilized. Moreover, for select patients unable to tolerate open surgery, novel techniques are emerging for selective ablation of the mesial temporal structures, including stereotactic radiosurgery (SRS). We present here a review of SRS as a potential therapy for MTLE, when open surgery is not an option.

  11. On the Ice Nucleation Spectrum

    Science.gov (United States)

    Barahona, D.

    2012-01-01

    This work presents a novel formulation of the ice nucleation spectrum, i.e. the function relating the ice crystal concentration to cloud formation conditions and aerosol properties. The new formulation is physically-based and explicitly accounts for the dependency of the ice crystal concentration on temperature, supersaturation, cooling rate, and particle size, surface area and composition. This is achieved by introducing the concepts of ice nucleation coefficient (the number of ice germs present in a particle) and nucleation probability dispersion function (the distribution of ice nucleation coefficients within the aerosol population). The new formulation is used to generate ice nucleation parameterizations for the homogeneous freezing of cloud droplets and the heterogeneous deposition ice nucleation on dust and soot ice nuclei. For homogeneous freezing, it was found that by increasing the dispersion in the droplet volume distribution the fraction of supercooled droplets in the population increases. For heterogeneous ice nucleation the new formulation consistently describes singular and stochastic behavior within a single framework. Using a fundamentally stochastic approach, both cooling rate independence and constancy of the ice nucleation fraction over time, features typically associated with singular behavior, were reproduced. Analysis of the temporal dependency of the ice nucleation spectrum suggested that experimental methods that measure the ice nucleation fraction over few seconds would tend to underestimate the ice nuclei concentration. It is shown that inferring the aerosol heterogeneous ice nucleation properties from measurements of the onset supersaturation and temperature may carry significant error as the variability in ice nucleation properties within the aerosol population is not accounted for. This work provides a simple and rigorous ice nucleation framework where theoretical predictions, laboratory measurements and field campaign data can be

  12. Rheology of planetary ices

    Energy Technology Data Exchange (ETDEWEB)

    Durham, W.B. [Lawrence Livermore National Lab., CA (United States); Kirby, S.H.; Stern, L.A. [Geological Survey, Menlo Park, CA (United States)

    1996-04-24

    The brittle and ductile rheology of ices of water, ammonia, methane, and other volatiles, in combination with rock particles and each other, have a primary influence of the evolution and ongoing tectonics of icy moons of the outer solar system. Laboratory experiments help constrain the rheology of solar system ices. Standard experimental techniques can be used because the physical conditions under which most solar system ices exist are within reach of conventional rock mechanics testing machines, adapted to the low subsolidus temperatures of the materials in question. The purpose of this review is to summarize the results of a decade-long experimental deformation program and to provide some background in deformation physics in order to lend some appreciation to the application of these measurements to the planetary setting.

  13. Ice accreditation vs wind

    Energy Technology Data Exchange (ETDEWEB)

    Sabourin, G. [Hydro-Quebec, PQ (Canada). TransEnergie Div.; Chouinard, L. [McGill Univ., Montreal, PQ (Canada); Feknous, N. [SNC-Lavalin, Montreal, PQ (Canada)

    2002-07-01

    Wind and ice data from Hydro Quebec and Environment Canada indicates that winds during ice storms are in the general direction of the St. Lawrence River. This observation is important for upgrading existing power transmission lines from the Manicouagan and Churchill generation system because they are parallel to the St. Lawrence and they were designed with lower criteria than is currently accepted. ASCE 74 suggests an accumulation ratio based on thickness of 0.70 for winds parallel to the line. The Goodwin model was used to calculate this ratio. The presentation includes illustrations showing the accumulation ratio for a north wind, as well as the accumulation ratios and wind roses at Quebec. A table showing a comparison of ratios from passive ice meters shows that results are similar to mean values from the theoretical model.

  14. El proyecto de restitución de tierras en Colombia: ¿ilustración de la fuerza civilizadora de la hipocresía?

    Directory of Open Access Journals (Sweden)

    Maria Paula Saffon

    2010-12-01

    Full Text Available El presente artículo ofrece una interpretación teórica acerca de las disposiciones sobre restitución de tierras contenidas en la famosa “Ley de Víctimas”, la cual fue debatida en el Congreso colombiano en el año 2008. El proyecto de ley preveía mecanismos específicos encaminados a garantizar la restitución de tierras a las víctimas del conflicto armado colombiano. En su momento, el proyecto de ley fue respaldado por los principales actores políticos del país, incluyendo el gobierno y las élites que lo apoyaban, por un lado, y las organizaciones de víctimas y de derechos humanos y los grupos de oposición, por el otro. El hecho de que todos los actores políticos del país estuviesen considerando seriamente la posibilidad de restituir las tierras a las víctimas del conflicto armado colombiano parecía indicar la existencia de un consenso entre actores políticos cuyas posiciones normalmente están enfrentadas, sobre un tema que tradicionalmente ha generado altos niveles de polarización. Le existencia de dicho consenso es desconcertante porque no parece corresponder ni a los intereses ni a la visión de justicia de dichos actores políticos, y además porque la restitución de tierras enfrenta enormes dificultades tanto prácticas como normativas, lo que indica que posiblemente no sea la mejor alternativa para enfrentar la problemática de distribución de tierras en Colombia. El artículo concluye que el respaldo dado por todos los actores al principio de justicia restaurativa podría llevar a su efectiva realización, y consiguientemente generar un resultado que a pesar de (o quizás por no ser intencional, podría contribuir sustancialmente a resolver el problema de la desigual distribución de tierras en Colombia

  15. Construcción sismorresistente en tierra: la gran experiencia contemporánea de la Pontificia Universidad Católica del Perú

    Directory of Open Access Journals (Sweden)

    Blondet, M.

    2011-09-01

    Full Text Available In many developing countries the most common alternative for dwelling construction is building with earth because the material is abundant and cheap. The quality of most traditional earthen construction is very low, because it is done informally, with little or no technical assistance. In seismic areas where earthen construction is common, every time an earthquake occurs, many dwellings collapse, causing considerable economic losses and tragic injuries and deaths. The professional and academic communities in some seismic countries have not remained indifferent to this important problem. Researchers at the Catholic University of Peru (PUCP have been investigating on the construction of earthen buildings in seismic areas for about 40 years and have obtained invaluable results. This article describes the evolution of the knowledge generated at PUCP of reinforced earth, a material composed of earth and compatible reinforcements, with which it is possible to build seismic-resistant constructions.

    En muchos países en vías de desarrollo la alternativa de vivienda más común es la construcción con tierra, pues el material es abundante y barato. La construcción tradicional de viviendas de tierra se realiza informalmente, sin asesoría técnica. Por ello, la calidad de estas construcciones es generalmente muy baja. En zonas sísmicas donde se construye con tierra, cada vez que ocurre un terremoto colapsan muchas construcciones de este material, causando considerables pérdidas económicas y lamentables pérdidas de vidas. Las comunidades académicas y profesionales de algunos países sísmicos no han permanecido impasibles frente a esta grave situación. En el Perú, investigadores de la Pontificia Universidad Católica del Perú (PUCP han venido investigando la construcción con tierra en áreas sísmicas desde hace cerca 40 años y han obtenido invalorables resultados. Este artículo describe la evolución del conocimiento generado en la

  16. Ice cores and palaeoclimate

    International Nuclear Information System (INIS)

    Krogh Andersen, K.; Ditlevsen, P.; Steffensen, J.P.

    2001-01-01

    Ice cores from Greenland give testimony of a highly variable climate during the last glacial period. Dramatic climate warmings of 15 to 25 deg. C for the annual average temperature in less than a human lifetime have been documented. Several questions arise: Why is the Holocene so stable? Is climatic instability only a property of glacial periods? What is the mechanism behind the sudden climate changes? Are the increased temperatures in the past century man-made? And what happens in the future? The ice core community tries to attack some of these problems. The NGRIP ice core currently being drilled is analysed in very high detail, allowing for a very precise dating of climate events. It will be possible to study some of the fast changes on a year by year basis and from this we expect to find clues to the sequence of events during rapid changes. New techniques are hoped to allow for detection of annual layers as far back as 100,000 years and thus a much improved time scale over past climate changes. It is also hoped to find ice from the Eemian period. If the Eemian layers confirm the GRIP sequence, the Eemian was actually climatically unstable just as the glacial period. This would mean that the stability of the Holocene is unique. It would also mean, that if human made global warming indeed occurs, we could jeopardize the Holocene stability and create an unstable 'Eemian situation' which ultimately could start an ice age. Currenlty mankind is changing the composition of the atmosphere. Ice cores document significant increases in greenhouse gases, and due to increased emissions of sulfuric and nitric acid from fossil fuel burning, combustion engines and agriculture, modern Greenland snow is 3 - 5 times more acidic than pre-industrial snow (Mayewski et al., 1986). However, the magnitude and abruptness of the temperature changes of the past century do not exceed the magnitude of natural variability. It is from the ice core perspective thus not possible to attribute the

  17. ICE Online Detainee Locator System

    Data.gov (United States)

    Department of Homeland Security — The Online Detainee Locator datasets provide the location of a detainee who is currently in ICE custody, or who was release from ICE custody for any reason with the...

  18. Excitatory amino acid transporters EAAT-1 and EAAT-2 in temporal lobe and hippocampus in intractable temporal lobe epilepsy

    DEFF Research Database (Denmark)

    Sarac, Sinan; Afzal, Shoaib; Broholm, Helle

    2009-01-01

    Intractable temporal lobe epilepsy (TLE) is an invalidating disease and many patients are resistant to medical treatment. Increased glutamate concentration has been found in epileptogenic foci and may induce local over-excitation and cytotoxicity; one of the proposed mechanisms involves reduced...... extra-cellular clearance of glutamate by excitatory amino acid transporters (EAAT-1 to EAAT-5). EAAT-1 and EAAT-2 are mainly expressed on astroglial cells for the reuptake of glutamate from the extra-cellular space. We have studied the expression of EAAT-1 and EAAT-2 in the hippocampus and temporal lobe...

  19. Ice recrystallization inhibition in ice cream as affected by ice structuring proteins from winter wheat grass.

    Science.gov (United States)

    Regand, A; Goff, H D

    2006-01-01

    Ice recrystallization in quiescently frozen sucrose solutions that contained some of the ingredients commonly found in ice cream and in ice cream manufactured under commercial conditions, with or without ice structuring proteins (ISP) from cold-acclimated winter wheat grass extract (AWWE), was assessed by bright field microscopy. In sucrose solutions, critical differences in moisture content, viscosity, ionic strength, and other properties derived from the presence of other ingredients (skim milk powder, corn syrup solids, locust bean gum) caused a reduction in ice crystal growth. Significant ISP activity in retarding ice crystal growth was observed in all solutions (44% for the most complex mix) containing 0.13% total protein from AWWE. In heat-shocked ice cream, ice recrystallization rates were significantly reduced 40 and 46% with the addition of 0.0025 and 0.0037% total protein from AWWE. The ISP activity in ice cream was not hindered by its inclusion in mix prior to pasteurization. A synergistic effect between ISP and stabilizer was observed, as ISP activity was reduced in the absence of stabilizer in ice cream formulations. A remarkably smoother texture for ice creams containing ISP after heat-shock storage was evident by sensory evaluation. The efficiency of ISP from AWWE in controlling ice crystal growth in ice cream has been demonstrated.

  20. The IceProd Framework

    DEFF Research Database (Denmark)

    Aartsen, M.G.; Abbasi, R.; Ackermann, M.

    2015-01-01

    of computational resources. IceProd is a distributed management system based on Python, XML-RPC and GridFTP. It is driven by a central database in order to coordinate and admin- ister production of simulations and processing of data produced by the IceCube detector. IceProd runs as a separate layer on top of other...

  1. 2006 Program of Study: Ice

    Science.gov (United States)

    2007-03-01

    form a debris flow. One such debris flow, initiated by a glacial lake flood in Peru in 1941, devastated the city of Huaraz, killing over 6000 people [5...ice, a series of’ prototype interlocking fingers is formed which grow ats the ice floes areI compressed and the ice floes plough through one another

  2. The anterior temporal lobes support residual comprehension in Wernicke's aphasia.

    Science.gov (United States)

    Robson, Holly; Zahn, Roland; Keidel, James L; Binney, Richard J; Sage, Karen; Lambon Ralph, Matthew A

    2014-03-01

    Wernicke's aphasia occurs after a stroke to classical language comprehension regions in the left temporoparietal cortex. Consequently, auditory-verbal comprehension is significantly impaired in Wernicke's aphasia but the capacity to comprehend visually presented materials (written words and pictures) is partially spared. This study used functional magnetic resonance imaging to investigate the neural basis of written word and picture semantic processing in Wernicke's aphasia, with the wider aim of examining how the semantic system is altered after damage to the classical comprehension regions. Twelve participants with chronic Wernicke's aphasia and 12 control participants performed semantic animate-inanimate judgements and a visual height judgement baseline task. Whole brain and region of interest analysis in Wernicke's aphasia and control participants found that semantic judgements were underpinned by activation in the ventral and anterior temporal lobes bilaterally. The Wernicke's aphasia group displayed an 'over-activation' in comparison with control participants, indicating that anterior temporal lobe regions become increasingly influential following reduction in posterior semantic resources. Semantic processing of written words in Wernicke's aphasia was additionally supported by recruitment of the right anterior superior temporal lobe, a region previously associated with recovery from auditory-verbal comprehension impairments. Overall, the results provide support for models in which the anterior temporal lobes are crucial for multimodal semantic processing and that these regions may be accessed without support from classic posterior comprehension regions.

  3. The auroral and ionospheric flow signatures of dual lobe reconnection

    Directory of Open Access Journals (Sweden)

    S. M. Imber

    2006-11-01

    Full Text Available We present the first substantial evidence for the occurrence of dual lobe reconnection from ionospheric flows and auroral signatures. The process of dual lobe reconnection refers to an interplanetary magnetic field line reconnecting with lobe field lines in both the northern and southern hemispheres. Two bursts of sunward plasma flow across the noon portion of the open/closed field line boundary (OCB, indicating magnetic flux closure at the dayside, were observed in SuperDARN radar data during a period of strongly northward IMF. The OCB is identified from spacecraft, radar backscatter, and auroral observations. In order for dual lobe reconnection to take place, we estimate that the interplanetary magnetic field clock angle must be within ±10° of zero (North. The total flux crossing the OCB during each burst is small (1.8% and 0.6% of the flux contained within the polar cap for the two flows. A brightening of the noon portion of the northern auroral oval was observed as the clock angle passed through zero, and is thought to be due to enhanced precipitating particle fluxes due to the occurrence of reconnection at two locations along the field line. The number of solar wind protons captured by the flux closure process was estimated to be ~2.5×1030 (4 tonnes by mass, sufficient to populate the cold, dense plasma sheet observed following this interval.

  4. Grooves on the occipital lobe of Indian brains.

    Science.gov (United States)

    Bisaria, K K

    1984-01-01

    The existence of a groove on the occipital lobe formed by the dural venous sinus or ridge has only rarely been described in the past. As observed in this study such grooves are either unilateral or bilateral and their incidence is very high in Indian brains. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:6490537

  5. Metabolic changes in occipital lobe epilepsy with automatisms

    Directory of Open Access Journals (Sweden)

    Chong H Wong

    2014-07-01

    Full Text Available Purpose: Some studies suggest that the pattern of glucose hypometabolism relates not only to the ictal-onset zone, but also reflects seizure propagation. We investigated metabolic changes in patients with occipital lobe epilepsy (OLE that may reflect propagation of ictal discharge during seizures with automatisms.Methods: Fifteen patients who had undergone epilepsy surgery for intractable OLE and had undergone interictal Fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET between 1994 and 2004 were divided into two groups (with and without automatisms during seizure. Significant regions of hypometabolism were identified by comparing 18F-FDG-PET results from each group with 16 healthy controls by using Statistical Parametric Mapping (SPM 2.Key Findings: Significant hypometabolism was confined largely to the epileptogenic occipital lobe in the patient group without automatisms. In patients with automatisms, glucose hypometabolism extended from the epileptogenic occipital lobe into the ipsilateral temporal lobe.Significance: We identified a distinctive hypometabolic pattern that was specific for OLE patients with automatisms during a seizure. This finding supports the postulate that seizure propagation is a cause of glucose hypometabolism beyond the region of seizure onset.

  6. Grooves on the occipital lobe of Indian brains.

    OpenAIRE

    Bisaria, K K

    1984-01-01

    The existence of a groove on the occipital lobe formed by the dural venous sinus or ridge has only rarely been described in the past. As observed in this study such grooves are either unilateral or bilateral and their incidence is very high in Indian brains.

  7. Metabolic changes in occipital lobe epilepsy with automatisms.

    Science.gov (United States)

    Wong, Chong H; Mohamed, Armin; Wen, Lingfeng; Eberl, Stefan; Somerville, Ernest; Fulham, Michael; Bleasel, Andrew F

    2014-01-01

    Some studies suggest that the pattern of glucose hypometabolism relates not only to the ictal-onset zone but also reflects seizure propagation. We investigated metabolic changes in patients with occipital lobe epilepsy (OLE) that may reflect propagation of ictal discharge during seizures with automatisms. Fifteen patients who had undergone epilepsy surgery for intractable OLE and had undergone interictal Fluorine-18-fluorodeoxyglucose positron-emission tomography ((18)F-FDG-PET) between 1994 and 2004 were divided into two groups (with and without automatisms during seizure). Significant regions of hypometabolism were identified by comparing (18)F-FDG-PET results from each group with 16 healthy controls by using statistical parametric mapping. Significant hypometabolism was confined largely to the epileptogenic occipital lobe in the patient group without automatisms. In patients with automatisms, glucose hypometabolism extended from the epileptogenic occipital lobe into the ipsilateral temporal lobe. We identified a distinctive hypometabolic pattern that was specific for OLE patients with automatisms during a seizure. This finding supports the postulate that seizure propagation is a cause of glucose hypometabolism beyond the region of seizure onset.

  8. Lung lobe torsion in dogs: 22 cases (1981-1999).

    Science.gov (United States)

    Neath, P J; Brockman, D J; King, L G

    2000-10-01

    To identify breed disposition, postoperative complications, and outcome in dogs with lung lobe torsion. Retrospective study. 22 client-owned dogs. Information on signalment; history; clinical findings; results of clinicopathologic testing, diagnostic imaging, and pleural fluid analysis; surgical treatment; intra- and postoperative complications; histologic findings; and outcome were obtained from medical records. All 22 dogs had pleural effusion; dyspnea was the most common reason for examination. Fifteen dogs were large deep-chested breeds; 5 were toy breeds. Afghan Hounds were overrepresented, compared with the hospital population. One dog was euthanatized without treatment; the remaining dogs underwent exploratory thoracotomy and lung lobectomy. Eleven dogs recovered from surgery without complications, but 3 of these later died of thoracic disease. Four dogs survived to discharge but had clinically important complications within 2 months, including chylothorax, mediastinal mesothelioma, gastric dilatation, and a second lung lobe torsion. Six dogs died or were euthanatized within 2 weeks after surgery because of acute respiratory distress syndrome, pneumonia, septic shock, pneumothorax, or chylothorax. Chylothorax was diagnosed in 8 of the 22 dogs, including 4 Afghan Hounds. Results suggest that lung lobe torsion is rare in dogs and develops most frequently in large deep-chested dogs, particularly Afghan Hounds. Other predisposing causes were not identified, but an association with chylothorax was evident, especially in Afghan Hounds. Prognosis for dogs with lung lobe torsion was fair to guarded.

  9. Brain Regions Underlying Word Finding Difficulties in Temporal Lobe Epilepsy

    Science.gov (United States)

    Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine

    2009-01-01

    Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance.…

  10. Bi‑lobed Perirectal Epidermoid Cyst: An Unusual Cause of ...

    African Journals Online (AJOL)

    of hematochezia and a bi-lobed cystic tumor on pelvic. MRI. We successfully resected the tumor via the posterior ... The only abnormal finding on clinical examination was a ... There was an absence of the uterus ... bleeding. Symptoms of dyschezia and hematochezia may also be due to cyst inflammation or infection while ...

  11. Surgical anatomy of the pyramidal lobe and its significance in ...

    African Journals Online (AJOL)

    33:35-37. 10. Harjeet A, Shani D, Jit I, Aggarwal AK. Shape, measurements and weight of the thyroid gland in northwest Indians. Surg Radiol Anat 2004;26:91-95. TABLE III. INVOLVEMENT OF THE PYRAMIDAL LOBE IN VARIOUS THYROID ...

  12. Auditory temporal processing in patients with temporal lobe epilepsy.

    Science.gov (United States)

    Lavasani, Azam Navaei; Mohammadkhani, Ghassem; Motamedi, Mahmoud; Karimi, Leyla Jalilvand; Jalaei, Shohreh; Shojaei, Fereshteh Sadat; Danesh, Ali; Azimi, Hadi

    2016-07-01

    Auditory temporal processing is the main feature of speech processing ability. Patients with temporal lobe epilepsy, despite their normal hearing sensitivity, may present speech recognition disorders. The present study was carried out to evaluate the auditory temporal processing in patients with unilateral TLE. The present study was carried out on 25 patients with epilepsy: 11 patients with right temporal lobe epilepsy and 14 with left temporal lobe epilepsy with a mean age of 31.1years and 18 control participants with a mean age of 29.4years. The two experimental and control groups were evaluated via gap-in-noise and duration pattern sequence tests. One-way ANOVA was run to analyze the data. The mean of the threshold of the GIN test in the control group was observed to be better than that in participants with LTLE and RTLE. Also, it was observed that the percentage of correct responses on the DPS test in the control group and in participants with RTLE was better than that in participants with LTLE. Patients with TLE have difficulties in temporal processing. Difficulties are more significant in patients with LTLE, likely because the left temporal lobe is specialized for the processing of temporal information. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Memory Functions following Surgery for Temporal Lobe Epilepsy in Children

    Science.gov (United States)

    Jambaque, Isabelle; Dellatolas, Georges; Fohlen, Martine; Bulteau, Christine; Watier, Laurence; Dorfmuller, Georg; Chiron, Catherine; Delalande, Olivier

    2007-01-01

    Surgical treatment appears to improve the cognitive prognosis in children undergoing surgery for temporal lobe epilepsy (TLE). The beneficial effects of surgery on memory functions, particularly on material-specific memory, are more difficult to assess because of potentially interacting factors such as age range, intellectual level,…

  14. The neurobiology of cognitive disorders in temporal lobe epilepsy

    Science.gov (United States)

    Bell, Brian; Lin, Jack J.; Seidenberg, Michael; Hermann, Bruce

    2013-01-01

    Cognitive impairment and especially memory disruption is a major complicating feature of the epilepsies. In this review we begin with a focus on the problem of memory impairment in temporal lobe epilepsy. We start with a brief overview of the early development of knowledge regarding the anatomic substrates of memory disorder in temporal lobe epilepsy, followed by discussion of the refinement of that knowledge over time as informed by the outcomes of epilepsy surgery (anterior temporal lobectomy) and the clinical efforts to predict those patients at greatest risk of adverse cognitive outcomes following epilepsy surgery. These efforts also yielded new theoretical insights regarding the function of the human hippocampus and a few examples of these insights are touched on briefly. Finally, the vastly changing view of temporal lobe epilepsy is examined including findings demonstrating that anatomic abnormalities extend far outside the temporal lobe, cognitive impairments extend beyond memory function, with linkage of these distributed cognitive and anatomic abnormalities pointing to a new understanding of the anatomic architecture of cognitive impairment in epilepsy. Challenges remain in understanding the origin of these cognitive and anatomic abnormalities, their progression over time, and most importantly, how to intervene to protect cognitive and brain health in epilepsy. PMID:21304484

  15. Memory, Metamemory and Their Dissociation in Temporal Lobe Epilepsy

    Science.gov (United States)

    Howard, Charlotte E.; Andres, Pilar; Broks, Paul; Noad, Rupert; Sadler, Martin; Coker, Debbie; Mazzoni, Giuliana

    2010-01-01

    Patients with temporal-lobe epilepsy (TLE) present with memory difficulties. The aim of the current study was to determine to what extent these difficulties could be related to a metamemory impairment. Fifteen patients with TLE and 15 matched healthy controls carried out a paired-associates learning task. Memory recall was measured at intervals of…

  16. Multidetector CT evaluation of potential right lobe living donors for ...

    African Journals Online (AJOL)

    Mohamed Saied Abdelgawad

    Multidetector CT evaluation of potential right lobe living donors for liver transplantation. Mohamed Saied Abdelgawad *, Osama L. El-Abd. National Liver Institute, El-Menoufiya University, Shebein El-Koom, Alexandria, Egypt. Received 4 June 2011; accepted 18 June 2011. KEYWORDS. Liver transplantation;. Multidetector ...

  17. Complications after mesial temporal lobe surgery via inferiortemporal gyrus approach.

    Science.gov (United States)

    Vale, Fernando L; Reintjes, Stephen; Garcia, Hermes G

    2013-06-01

    The purpose of this study was to identify the complications associated with the inferior temporal gyrus approach to anterior mesial temporal lobe resection for temporal lobe epilepsy. This retrospective study examined complications experienced by 483 patients during the 3 months after surgery. All surgeries were performed during 1998-2012 by the senior author (F.L.V.). A total of 13 complications (2.7%) were reported. Complications were 8 delayed subdural hematomas (1.6%), 2 superficial wound infections (0.4%), 1 delayed intracranial hemorrhage (0.2%), 1 small lacunar stroke (0.2%), and 1 transient frontalis nerve palsy (0.2%). Three patients with subdural hematoma (0.6%) required readmission and surgical intervention. One patient (0.2%) with delayed intracranial hemorrhage required readmission to the neuroscience intensive care unit for observation. No deaths or severe neurological impairments were reported. Among the 8 patients with subdural hematoma, 7 were older than 40 years (87.5%); however, this finding was not statistically significant (p = 0.198). The inferior temporal gyrus approach to mesial temporal lobe resection is a safe and effective method for treating temporal lobe epilepsy. Morbidity and mortality rates associated with this procedure are lower than those associated with other neurosurgical procedures. The finding that surgical complications seem to be more common among older patients emphasizes the need for early surgical referral of patients with medically refractory epilepsy.

  18. Bilingualism Alters Children's Frontal Lobe Functioning for Attentional Control

    Science.gov (United States)

    Arredondo, Maria M.; Hu, Xiao-Su; Satterfield, Teresa; Kovelman, Ioulia

    2017-01-01

    Bilingualism is a typical linguistic experience, yet relatively little is known about its impact on children's cognitive and brain development. Theories of bilingualism suggest that early dual-language acquisition can improve children's cognitive abilities, specifically those relying on frontal lobe functioning. While behavioral findings present…

  19. Polar Stereographic Valid Ice Masks Derived from National Ice Center Monthly Sea Ice Climatologies, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — These valid ice masks provide a way to remove spurious ice caused by residual weather effects and land spillover in passive microwave data. They are derived from the...

  20. Una Nota sobre la Construcción de Series de Precios de Activos Reales: Tierra y Casas en Chile Una Nota sobre la Construcción de Series de Precios de Activos Reales: Tierra y Casas en Chile

    OpenAIRE

    Raimundo Soto; Felipe Morandé

    1992-01-01

    Una Nota sobre la Construcción de Series de Precios de Activos Reales: Tierra y Casas en Chile This note presents previously unpublished data on prices of agricultural land in Chile's central region and houses (both rental and purchasing prices) in Santiago, with the corresponding methodology. As such, it is a follow-up to an Appendix in Morande (1992).

  1. User's guide for ICE

    International Nuclear Information System (INIS)

    Fraley, S.K.

    1976-07-01

    ICE is a cross-section mixing code which will accept cross sections from an AMPX working library and produce mixed cross sections in the AMPX working library format, ANISN format, and the group-independent ANISN format. User input is in the free-form or fixed-form FIDO structure. The code is operable as a module in the AMPX system

  2. Autosub under ice

    OpenAIRE

    Griffiths, G.

    2005-01-01

    Autosub made headlines recently when it became trapped under 200m of ice in Antarctica.Here we explore the ideas behind the £5.86 million research programme, and look back at an earlier expedition which took place last summer off the coast of Greenland.

  3. Melting ice, growing trade?

    Directory of Open Access Journals (Sweden)

    Sami Bensassi

    2016-05-01

    Full Text Available Abstract Large reductions in Arctic sea ice, most notably in summer, coupled with growing interest in Arctic shipping and resource exploitation have renewed interest in the economic potential of the Northern Sea Route (NSR. Two key constraints on the future viability of the NSR pertain to bathymetry and the future evolution of the sea ice cover. Climate model projections of future sea ice conditions throughout the rest of the century suggest that even under the most “aggressive” emission scenario, increases in international trade between Europe and Asia will be very low. The large inter-annual variability of weather and sea ice conditions in the route, the Russian toll imposed for transiting the NSR, together with high insurance costs and scarce loading/unloading opportunities, limit the use of the NSR. We show that even if these obstacles are removed, the duration of the opening of the NSR over the course of the century is not long enough to offer a consequent boost to international trade at the macroeconomic level.

  4. Ecology under lake ice

    NARCIS (Netherlands)

    Hampton, Stephanie E.; Galloway, Aaron W. E.; Powers, Stephen M.; Ozersky, Ted; Woo, Kara H.; Batt, Ryan D.; Labou, Stephanie G.; O'Reilly, Catherine M.; Sharma, Sapna; Lottig, Noah R.; Stanley, Emily H.; North, Rebecca L.; Stockwell, Jason D.; Adrian, Rita; Weyhenmeyer, Gesa A.; Arvola, Lauri; Baulch, Helen M.; Bertani, Isabella; Bowman, Larry L., Jr.; Carey, Cayelan C.; Catalan, Jordi; Colom-Montero, William; Domine, Leah M.; Felip, Marisol; Granados, Ignacio; Gries, Corinna; Grossart, Hans-Peter; Haberman, Juta; Haldna, Marina; Hayden, Brian; Higgins, Scott N.; Jolley, Jeff C.; Kahilainen, Kimmo K.; Kaup, Enn; Kehoe, Michael J.; MacIntyre, Sally; Mackay, Anson W.; Mariash, Heather L.; Mckay, Robert M.; Nixdorf, Brigitte; Noges, Peeter; Noges, Tiina; Palmer, Michelle; Pierson, Don C.; Post, David M.; Pruett, Matthew J.; Rautio, Milla; Read, Jordan S.; Roberts, Sarah L.; Ruecker, Jacqueline; Sadro, Steven; Silow, Eugene A.; Smith, Derek E.; Sterner, Robert W.; Swann, George E. A.; Timofeyev, Maxim A.; Toro, Manuel; Twiss, Michael R.; Vogt, Richard J.; Watson, Susan B.; Whiteford, Erika J.; Xenopoulos, Marguerite A.

    Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experi-ence periods of snow and ice cover. Relatively little is known of winter ecology in these systems,due to a historical research focus on summer ‘growing seasons’. We executed the first global

  5. Design of a grounding network in electrical substations. Materials and formulas the most used; Diseno de redes de tierra en subestaciones electricas. Materiales y formulas mas utilizadas

    Energy Technology Data Exchange (ETDEWEB)

    Raull Martin, J. [Facultad de Ingenieria, UNAM, Mexico, D.F. (Mexico)

    2000-09-01

    The purpose of this paper is to present a summarized version of the different types of construction of grounding systems, as well as their materials and formulas, which are necessary and useful for the design and building of a grounding network for medium to high voltage facilities. A description is also made of how to determine the electrical resistivity of subsoil layers with different physical characteristics. Several illustrative examples are also solved in the paper. [Spanish] El proposito de este articulo es presentar de manera resumida los diferentes tipos de construccion de los sistemas de tierra, asi como sus materiales y formulas, los cuales son necesarios y utiles para el diseno y edificacion de una red de tierra para instalaciones de mediana y alta tension. Se describe tambien la obtencion de las diferentes resistividades que presenta los terrenos con diversas caracteristicas fisicas. Asimismo, se solucionan ejercicios ilustrativos a lo largo del articulo.

  6. Neutralizar la degradación de las tierras, una aspiración global. ¿Es posible lograrlo en México?

    OpenAIRE

    Armando López Santos

    2016-01-01

    Neutralizar la degradación de las tierras (LDN, por sus siglas en inglés) o equilibrar su deterioro, es un reto planteado por el Comité de Ciencia y Tecnología (CCT) de la Convención de las Naciones Unidas de Lucha Contra la Desertificación (UNCCD, por sus siglas en inglés), de la que México forma parte, es un concepto moderno que va más allá del recurso edáfico, que expresa un objetivo aspiracional global y una meta voluntaria nacional para contrarrestar el avance de la degradación de tierra...

  7. Transient analysis for grounding systems considering the ground ionization; Analisis transitorio de sistemas de puesta a tierra considerando la ionizacion del suelo

    Energy Technology Data Exchange (ETDEWEB)

    Salgado Salgado, Luis Alberto

    2008-06-15

    All electrical installation must have an effective grounding system. The purpose of this grounding system is to provide a low impedance path for draining electric currents generated by faults, switching operations or atmospheric discharges to earth, avoiding damage to people, equipment or installations. High currents drained to ground leads to an electric field which can be capable of breaking down the dielectric strength of the ground. When this happens, the ionization phenomena takes place, which reduce the grounding system impedance and modify its performance. In this thesis, a computational model for evaluating the transient performance of grounding systems subjected to high magnitude and frequency currents is presented. The model is based in a transmission line approach and the grounding system transient analysis is carried out in the frequency domain. The time domain translation is performed by means of the Fast Fourier Inverse Transform (FFIT). The computer model is capable of simulating soil ionization. The computer model developed is used to study the performance of vertical rods and grounding grids of different sizes. In every case, different electric field magnitudes and soil's resistivity were used, currents of different frequency components and magnitude values where used as well. The obtained results presented were compared and validated with other computer model results and measurements published in the literature. [Spanish] Toda instalacion electrica debe contar con un sistema de puesta a tierra efectivo. La finalidad de este sistema es proporcionar un camino de baja impedancia para drenar a tierra las corrientes generadas por fallas, maniobras o fenomenos naturales como las descargas atmosfericas, evitando de esta manera danos a las personas, equipos o instalaciones. Cuando las corrientes drenadas a tierra son de gran magnitud se origina un campo electrico critico capaz de romper la rigidez dielectrica del suelo que rodea los conductores del

  8. Ice shelf fracture parameterization in an ice sheet model

    Directory of Open Access Journals (Sweden)

    S. Sun

    2017-11-01

    Full Text Available Floating ice shelves exert a stabilizing force onto the inland ice sheet. However, this buttressing effect is diminished by the fracture process, which on large scales effectively softens the ice, accelerating its flow, increasing calving, and potentially leading to ice shelf breakup. We add a continuum damage model (CDM to the BISICLES ice sheet model, which is intended to model the localized opening of crevasses under stress, the transport of those crevasses through the ice sheet, and the coupling between crevasse depth and the ice flow field and to carry out idealized numerical experiments examining the broad impact on large-scale ice sheet and shelf dynamics. In each case we see a complex pattern of damage evolve over time, with an eventual loss of buttressing approximately equivalent to halving the thickness of the ice shelf. We find that it is possible to achieve a similar ice flow pattern using a simple rule of thumb: introducing an enhancement factor ∼ 10 everywhere in the model domain. However, spatially varying damage (or equivalently, enhancement factor fields set at the start of prognostic calculations to match velocity observations, as is widely done in ice sheet simulations, ought to evolve in time, or grounding line retreat can be slowed by an order of magnitude.

  9. Ice shelf fracture parameterization in an ice sheet model

    Science.gov (United States)

    Sun, Sainan; Cornford, Stephen L.; Moore, John C.; Gladstone, Rupert; Zhao, Liyun

    2017-11-01

    Floating ice shelves exert a stabilizing force onto the inland ice sheet. However, this buttressing effect is diminished by the fracture process, which on large scales effectively softens the ice, accelerating its flow, increasing calving, and potentially leading to ice shelf breakup. We add a continuum damage model (CDM) to the BISICLES ice sheet model, which is intended to model the localized opening of crevasses under stress, the transport of those crevasses through the ice sheet, and the coupling between crevasse depth and the ice flow field and to carry out idealized numerical experiments examining the broad impact on large-scale ice sheet and shelf dynamics. In each case we see a complex pattern of damage evolve over time, with an eventual loss of buttressing approximately equivalent to halving the thickness of the ice shelf. We find that it is possible to achieve a similar ice flow pattern using a simple rule of thumb: introducing an enhancement factor ˜ 10 everywhere in the model domain. However, spatially varying damage (or equivalently, enhancement factor) fields set at the start of prognostic calculations to match velocity observations, as is widely done in ice sheet simulations, ought to evolve in time, or grounding line retreat can be slowed by an order of magnitude.

  10. Autonomous Ice Mass Balance Buoys for Seasonal Sea Ice

    Science.gov (United States)

    Whitlock, J. D.; Planck, C.; Perovich, D. K.; Parno, J. T.; Elder, B. C.; Richter-Menge, J.; Polashenski, C. M.

    2017-12-01

    The ice mass-balance represents the integration of all surface and ocean heat fluxes and attributing the impact of these forcing fluxes on the ice cover can be accomplished by increasing temporal and spatial measurements. Mass balance information can be used to understand the ongoing changes in the Arctic sea ice cover and to improve predictions of future ice conditions. Thinner seasonal ice in the Arctic necessitates the deployment of Autonomous Ice Mass Balance buoys (IMB's) capable of long-term, in situ data collection in both ice and open ocean. Seasonal IMB's (SIMB's) are free floating IMB's that allow data collection in thick ice, thin ice, during times of transition, and even open water. The newest generation of SIMB aims to increase the number of reliable IMB's in the Arctic by leveraging inexpensive commercial-grade instrumentation when combined with specially developed monitoring hardware. Monitoring tasks are handled by a custom, expandable data logger that provides low-cost flexibility for integrating a large range of instrumentation. The SIMB features ultrasonic sensors for direct measurement of both snow depth and ice thickness and a digital temperature chain (DTC) for temperature measurements every 2cm through both snow and ice. Air temperature and pressure, along with GPS data complete the Arctic picture. Additionally, the new SIMB is more compact to maximize deployment opportunities from multiple types of platforms.

  11. Improved ice loss estimate of the northwestern Greenland ice sheet

    DEFF Research Database (Denmark)

    Kjeldsen, Kristian Kjellerup; Khan, Shfaqat Abbas; Wahr, J.

    2013-01-01

    We estimate ice volume change rates in the northwest Greenland drainage basin during 2003–2009 using Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data. Elevation changes are often reported to be largest near the frontal portion of outlet glaciers. To improve the volume change...... estimate, we supplement the ICESat data with altimeter surveys from NASA's Airborne Topographic Mapper from 2002 to 2010 and NASA's Land, Vegetation and Ice Sensor from 2010. The Airborne data are mainly concentrated along the ice margin and thus have a significant impact on the estimate of the volume...... change. Our results show that adding Airborne Topographic Mapper and Land, Vegetation and Ice Sensor data to the ICESat data increases the catchment-wide estimate of ice volume loss by 11%, mainly due to an improved volume loss estimate along the ice sheet margin. Furthermore, our results show...

  12. Southern Alaska Glaciers: Spatial and Temporal Variations in Ice Volume

    Science.gov (United States)

    Sauber, J.; Molnia, B. F.; Lutchke, S.; Rowlands, D.; Harding, D.; Carabajal, C.; Hurtado, J. M.; Spade, G.

    2004-01-01

    Although temperate mountain glaciers comprise less than 1% of the glacier-covered area on Earth, they are important because they appear to be melting rapidly under present climatic conditions and, therefore, make significant contributions to rising sea level. In this study, we use ICESat observations made in the last 1.5 years of southern Alaska glaciers to estimate ice elevation profiles, ice surface slopes and roughness, and bi-annual and/or annual ice elevation changes. We report initial results from the near coastal region between Yakutat Bay and Cape Suckling that includes the Malaspina and Bering Glaciers. We show and interpret ice elevations changes across the lower reaches of the Bagley Ice Valley for the period between October 2003 and May 2004. In addition, we use off-nadir pointing observations to reference tracks over the Bering and Malaspina Glaciers in order to estimate annual ice elevation change. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Shuttle Radar Topography Mission (SRTM) derived DEMs are used to estimate across track regional slopes between ICESat data acquisitions. Although the distribution and quantity of ICESat elevation profiles with multiple, exact repeat data is currently limited in Alaska, individual ICESat data tracks, provide an accurate reference surface for comparison to other elevation data (e.g. ASTER and SRTM X- and C-band derived DEMs). Specifically we report the elevation change over the Malaspina Glacier's piedmont lobe between a DEM derived from SRTM C-band data acquired in Feb. 2000 and ICESat Laser #2b data from Feb.-March 2004. We also report use of ICESat elevation data to enhance ASTER derived absolute DEMs. Mountain glaciers generally have rougher surfaces and steeper regional slopes than the ice sheets for which the ICESat design was optimized. Therefore, rather than averaging ICESat observations over large regions or relying on crossovers, we are working with well-located ICESat

  13. Neutralizar la degradación de las tierras, una aspiración global. ¿Es posible lograrlo en México?

    Directory of Open Access Journals (Sweden)

    Armando López Santos

    2016-04-01

    Full Text Available Neutralizar la degradación de las tierras (LDN, por sus siglas en inglés o equilibrar su deterioro, es un reto planteado por el Comité de Ciencia y Tecnología (CCT de la Convención de las Naciones Unidas de Lucha Contra la Desertificación (UNCCD, por sus siglas en inglés, de la que México forma parte, es un concepto moderno que va más allá del recurso edáfico, que expresa un objetivo aspiracional global y una meta voluntaria nacional para contrarrestar el avance de la degradación de tierras al 2030. De ponerse en marcha, implicaría detener o revertir la tendencia de disminución de calidad físico-biótica (agua-suelo-planta-atmósfera que sostiene el funcionamiento de los ecosistemas, de manera que esto permita conseguir un estado de equilibrio suficiente para mantener un nivel de salud ecosistémica y una garantía en la seguridad alimentaria para las generaciones futuras. El objetivo del presente ensayo fue analizar qué posibilidades tiene México para poner en marcha los principios y acciones necesarias para prevenir, detener y revertir el ritmo de degradación de sus tierras. Un breve análisis de las circunstancias, tanto a nivel global como en el contexto nacional, donde se vislumbran dificultades para conciliar la política ambiental con las metas de crecimiento económico o asumir las consecuencias por la sobre-explotación evidente de los recursos territoriales, de lo contrario LDN solo llegará a ser un reto frustrado ante la tendencia de la degradación de las tierras y comprometiendo con ello cada vez más la calidad de vida de las futuras generaciones.

  14. Composición florística de dos bosques (Tierra firme y varzea) en la región de Araracuara, Amazonia Colombiana

    OpenAIRE

    Londoño Vega Ana Catalina; Alvarez Dávila Estéban

    1997-01-01

    Two rain forests of the Araracuara region (Colombian Amazon) are described and compared in terms of vascular terrestrial plant composition. Two 1.8 ha rectangular plots, located in upland (tierra firme) and seasonally flooded (várzea) sites, were sampled for individuals taller than 0.5 m. A total of 1149 species, 347 genera and 98 families were found. Arborescent species comprised 65% of the total at both sites; climbers (woody and herbaceous) contributed 24%, shrubs 8% and terrestrial herbs ...

  15. El acaparamiento de tierras en América Latina y el Caribe visto desde una perspectiva internacional más amplia

    NARCIS (Netherlands)

    S.M. Borras jr. (Saturnino); J.C. Franco (Jennifer); C. Kay (Cristóbal); M. Spoor (Monique)

    2012-01-01

    markdownabstractEste volumen continúa la discusión surgida de los antecedentes recogidos en la investigación presentada en el libro “Dinámicas del mercado de la tierra en América Latina y el Caribe: concentración y extranjerización”, publicado por la Oficina Regional de la FAO en junio de

  16. Heterogeneous ice nucleation

    Energy Technology Data Exchange (ETDEWEB)

    Bogdan, A. [Helsinki Univ. (Finland). Dept. of Physics

    1994-12-31

    The classical theory of heterogenous ice nucleation is reviewed in detail. The modelling of ice nucleation in the adsorbed water films on natural particles by analogous ice nucleation in adsorbed water films on the walls of porous media is discussed. Ice nucleation in adsorbed films of purewater and the HNO{sub 3}/H{sub 2}0 binary system on the surface of porous aerosol (SiO{sub 2}) was investigated using the method of NMR spectroscopy. The median freezing temperature and freezing temperature region were shown to be highly sensitive both to the average thickness of the adsorbed films and to the amount of adsorbed nitric acid. The character of the ice phase formation tends to approach that of bulk liquid with increasing adsorbed film thickness. Under the given conditions the thickness of the adsorbed films decreases with an increasing amount of adsorbed nitric acid molecules The molar concentration of nitric acid in the adsorbed films is very small (of the order of 10{sup -}3 10{sup -}2 (M/l)). Nitric acid molecules tend to adsorb on the surface of aerosol to a greater extent than in subsequent layers. The concentration is greatest in layers situated close to the surface and sharply decreases with the distance from the surface. The difference between the median freezing temperatures for adsorbed pure water and for the binary system was found to be about 9 K for films of equal thickness. This is about 150 times greater than the difference between the median freezing temperatures of bulk pure water and a solution with the same concentration of nitric acid. (orig.)

  17. Cartografía mediante imágenes Landsat de suelos salinos en la tierra de Medina (Valladolid

    Directory of Open Access Journals (Sweden)

    García Rodríguez, M. P.

    2010-07-01

    Full Text Available The main goal of this study is the mapping of saline soils (solonchaks, solonetzs and luvisols with salic phases in «Tierra de Medina» (Valladolid using images of the TM and ETM sensors of the Landsat satellites. The spectral signatures of these soils show very high digital values, which allows to differentiate them from other types of soils and superficial covers. The highest values correspond to those which have salt efflorescences and the lowest values to soils affected by hydromorphic processes. The images obtained with the NDVI do not allow a clear discrimination of saline soils, but they allow to interpret the changes in their use. In these soils the values of NDVI are very low, due to their scarce vegetation. There is a remarkable vegetation reduction between years 1987 and 2001, which implies a structure deterioration and a great loss of vegetal cover; many of soils affected by salinization have not been cultivated any more.

    El objetivo del estudio es cartografiar los suelos salinos (solonchaks, solonetzs y luvisoles con fases sálicas en la Tierra de Medina (Valladolid utilizado imágenes de los sensores TM y ETM de los satélites Landsat. Las signaturas espectrales de estos suelos muestran valores digitales muy altos, lo que permite diferenciarlos de otros tipos de suelos y cubiertas superficiales. Los valores más altos corresponden a los que tienen eflorescencias salinas en superficie y los más bajos a los suelos afectados por hidromorfismo. Las imágenes obtenidas con el NDVI no permiten una clara discriminación de los suelos salinos, pero sí interpretar los cambios en su uso. En estos suelos los valores de NDVI son muy bajos, acordes con su escasa vegetación. Hay un notable descenso entre los años 1987 y 2001, lo que implica un deterioro de su estructura y una gran pérdida de cubierta vegetal; muchos de los suelos afectados por salinización se han dejado de cultivar. [fr] L’objectif de l’étude est

  18. Remote infarct of the temporal lobe with coexistent hippocampal sclerosis in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Gales, Jordan M; Prayson, Richard A

    2016-02-01

    In patients undergoing surgery for temporal lobe epilepsy, hippocampal sclerosis remains the most commonly observed pathology. In addition to hippocampal sclerosis, 5% to 30% of these resections on magnetic resonance imaging contain a second independently epileptogenic lesion, commonly referred to as dual pathology. A second etiology of seizure activity, as seen in dual pathology, may serve as an important cause of treatment failure in striving for post-operative seizure control. Dual pathology, consisting of hippocampal sclerosis and a remote infarct of the adjacent cortex, has been rarely reported. Cases of pathologically confirmed hippocampal sclerosis diagnosed between January 2000 and December 2012 (n = 349) were reviewed, and 7 cases of coexistent infarct (2%) formed the study group. Seven individuals (mean age, 29years; range, 5-47 years) with a mean epilepsy duration of 12.5years (3.3-25 years) and a mean pre-surgery frequency of 15 seizures per week (range, 0.5-56 seizures/week) were followed up postoperatively for a mean duration of 64months (range, 3-137 months). Pathologically, the most common form of hippocampal sclerosis observed was International League against Epilepsy type Ib or severe variant (n = 4). Four of the six individuals with post-surgery follow-up were seizure free at last encounter. The reported incidence of dual pathology, including hippocampal sclerosis and remote infarct, is low (2% in the present study) but may indicate a slightly increased risk of developing hippocampal sclerosis in the setting of a remote infarct. Surgical intervention for such cases anecdotally appears effective in achieving seizure control. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Calculation of lobe mixer flow with reynolds stress model. Oryoku hoteishiki model ni yoru lobe mixer ryu no suchi keisan

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Makoto; Arakawa, Chuichi; Tagori, Tetsuo [Ishikawajima-Harima Heavy Industries, Co., Ltd., Tokyo (Japan) Univ. of Tokyo, Tokyo (Japan). Faculty of Engineering Univ. of Tsukuba, Tsukuba (Japan)

    1990-02-25

    It is considered that exhaust gas energy of turbofan engine is partly collected to realize the improvement of propulsion efficiency together with the reduction of noise appeared by the change in velocity distribution of exhaust gas flow. Then Lobe mixer was studied and its effectiveness was widely recognized, however the development of more realistic prediction method of exhaust nozzle system including Lobe mixer, is not completed yet. The stress equation model with low Reynolds Number which is easily used by the expansion of Launder Reece Rodi model in three dimension coordinate system was newly constructed. Applicability of the stress equation in more complicated flow field was greatly improved. While the above model was applied to Lobe mixer system, then the qualitative reproduction of mixing process accompanied with flow around Lobe and longitudinal eddy of core or bi-pass flow, was realized. There is room for improvement of pressure strain correlation term and behavior of Reynolds stress very close by wall surface in this model. 16 refs., 9 figs., 1 tab.

  20. Bibliography of Ice Properties and Forecasting Related to Transportation in Ice-Covered Waters.

    Science.gov (United States)

    1980-09-01

    N. and Tabata , T., Ice study in the Gulf of Peschanskii, I.S., Ice science and ice technology, Bothnia, III: observations on large grains of ice...ice and by Sterrett, K.F., The arctic environment and the hitting ice floes. Results of these measurements have arctic surface effect vehicle, Cold...ice growth, temperature 26-3673 effects, ice cover thickness. 28-557 Determining contact stresses when a ship’s stem hits the ice, Kheisin, D.E

  1. A new form of land concentration in Colombia Una nueva forma de concentración de la tierra en Colombia:la ley 1448 de 2011

    Directory of Open Access Journals (Sweden)

    Juan Pablo Henao Guzmán

    2012-06-01

    Full Text Available This article aims to show how the Law 1448 of 2011, which explains reparation and restitution of victims, and the National Development Plan (NDP 2011-2014 generate land concentration in Colombia. This is due to how the NDP objectives disintegrate the Law 1448 objectives; this phenomenon could be explained using an agency model and the subsequent moral risk issue formed between the State and the victims. Regarding these results, a game-theory model was built, and this effectively concludes that the Law 1448 and the NDP generate land concentration in ColombiaEn este artículo se pretende mostrar, mediante un análisis económico, cómo la Ley 1448 de 2011 (o Ley de Víctimas y Restitución de Tierras, junto al Plan Nacional de Desarrollo (PND 2011-2014, generan concentración de la tierra en Colombia. Esto se debe a que los objetivos del PND terminan disgregando los que busca la Ley 1448, lo cual se explica con el uso de un modelo de agencia y el subsecuente problema de riesgo moral para el Estado y las víctimas del conflicto. A partir de los resultados anteriores se construye un modelo de teoría de juegos, del que se concluye que, efectivamente, la Ley 1448 y el PND generan concentración de la tierra en Colombia.

  2. Producción de biomasa aérea y uso equivalente de la tierra en intercultivos de alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    T. W Pereyra

    Full Text Available Tradicionalmente, el incremento de la productividad se ha asociado al aumento del rendimiento a través del mejoramiento genético y las prácticas de manejo del cultivo. Sin embargo, si se considera la producción por unidad de área y de tiempo, el sistema de intercultivos puede ser otra forma de mejorar la rentabilidad. El objetivo del experimento fue determinar la biomasa producida y el uso equivalente de la tierra en monocultivo e intercultivos de alfalfa (Medicago sativa L. con sorgo sudán (Sorghum sudanense L. y avena (Avena sativa L.. Se determinó la biomasa aérea de todos los tratamientos (expresada por unidad de superficie y el uso equivalente de la tierra. El diseño fue completamente aleatorizado, dispuesto en bloques con dos repeticiones. Los resultados se sometieron a un ANOVA y las medias se compararon mediante la prueba de Duncan, a través del paquete estadístico INFOSTAT. El intercultivo alfalfa-sorgo triplicó la producción de alfalfa en relación con el monocultivo, mientras que alfalfa-avena no superó la producción de alfalfa pura en los meses de invierno. El intercultivo alfalfa-sorgo fue un 57 % más eficiente en el uso de la tierra que sus respectivos monocultivos, mientras que alfalfa-avena no logró superar la unidad.

  3. Persuasión lingüística para la defensa de la tierra: El Título Primordial de Santiago Sula

    Directory of Open Access Journals (Sweden)

    Marta Puente González

    2016-07-01

    Full Text Available Los pueblos de indios de la Nueva España crearon, a fines de la época colonial, una forma de  defender sus territorios ante la amenaza de colonos españoles, criollos y otros indios que usurpaban ilegalmente terrenos e intentaban rentabilizar el control de las tierras. Empezaron a producir un tipo de textos, sus Títulos Primordiales, que presentaban en los juicios para demostrar la titularidad de sus posesiones. No son textos del tipo administrativo, sino que insertan narraciones con los acontecimientos pasados más importantes para la comunidad. Pero principalmente son escritos que fueron pensados para persuadir a los receptores de la veracidad de sus argumentos. Buscaban convencer, en lo lingüístico y textual, para tener efecto en la vida real: que no se les arrebatase sus tierras. En este trabajo se abordará la aproximación a este tipo textual mediante el estudio, desde la pragmática lingüística y el análisis del discurso, del Título Primordial de Santiago Sula, un documento paradigmático del género. Con ello se quiere demostrar que el Título Primordial de Santiago Sulase caracteriza por una estructura argumentativa con un narrador que dispone de distintos tipos de argumentos y otras estrategias textuales para reforzar la única conclusión final: la defensa dela tierra.

  4. Los ocupantes de tierras en la Norpatagonia. Los Inspectores nacionales, el colono ideal y el poblador real al comenzar el siglo XX

    Directory of Open Access Journals (Sweden)

    Blanco, Graciela

    2016-12-01

    Full Text Available El presente trabajo realiza una aproximación a los pobladores que se asentaron en el norte de la Patagonia Argentina, particularmente en el Territorio de Río Negro, a partir de los informes de inspección realizados por funcionarios de la Dirección Nacional de Tierras en los años 1904, 1910 y 1920-21. Estos informes no abarcan la totalidad del territorio, inspeccionándose en esos años distintas zonas, particularmente las destinadas a funcionar como colonias o reservas –Conesa, Choele Choel, Frias, El Cuy, Valcheta-. Los mismos dan cuenta de los pobladores, la forma de tenencia de la tierra, la producción y las inversiones realizadas, clasificando y calificando a los pobladores de acuerdo a diferentes variables. El relato construido por estos inspectores resultaba el insumo más importante a la hora de decidir el acceso a la tierra. Se estudian los informes que estos agentes estatales producían, caracterizando las condiciones del poblamiento y puesta en producción de la región por parte de los pequeños productores de ganado menor o crianceros, complementando esas fuentes con la prensa regional y la producción existente sobre el tema.

  5. Seismically-induced soft-sediment deformation structures associated with the Magallanes-Fagnano Fault System (Isla Grande de Tierra del Fuego, Argentina)

    Science.gov (United States)

    Onorato, M. Romina; Perucca, Laura; Coronato, Andrea; Rabassa, Jorge; López, Ramiro

    2016-10-01

    In this paper, evidence of paleoearthquake-induced soft-sediment deformation structures associated with the Magallanes-Fagnano Fault System in the Isla Grande de Tierra del Fuego, southern Argentina, has been identified. Well-preserved soft-sediment deformation structures were found in a Holocene sequence of the Udaeta pond. These structures were analyzed in terms of their geometrical characteristics, deformation mechanism, driving force system and possible trigger agent. They were also grouped in different morphological types: sand dykes, convolute lamination, load structures and faulted soft-sediment deformation features. Udaeta, a small pond in Argentina Tierra del Fuego, is considered a Quaternary pull-apart basin related to the Magallanes-Fagnano Fault System. The recognition of these seismically-induced features is an essential tool for paleoseismic studies. Since the three main urban centers in the Tierra del Fuego province of Argentina (Ushuaia, Río Grande and Tolhuin) have undergone an explosive growth in recent years, the results of this study will hopefully contribute to future analyses of the seismic risk of the region.

  6. «Le Domaine de la Terre», un conjunto de realizaciones-piloto a base de tierra, en L'isle D'abeau (Francia

    Directory of Open Access Journals (Sweden)

    Salas, J.

    1986-02-01

    Full Text Available In this work, some of the experimental housing works (blocks, formwork, mud and straw... built on the outskirts of Lyon (France are presented in a systematic way. The ensemble is called «Le Domaine de la Terre», and eleven different projects are concerned, where a number of institutions and teams of professionals have worked. In its whole it is an excelent exposition at natural scale of the possibilities of mud construction, even though the results are of a great diversity -formal and conceptually- between those diverse projects.Se presentan en el trabajo de forma sistematizada algunas de las realizaciones de viviendas experimentales a base de tierra (bloques, tapial, bloques compactados, tierra-paja.... realizadas en las cercanías de Lyon (Francia y que constituyen el conjunto «Le Domaine de la Terre». Se trata de una realización a base de once proyectos distintos en los que han intervenido un buen número de instituciones, equipos de proyecto y profesionales franceses. Globalmente constituyen una excelente exposición a escala natural de las posibilidades de las construcciones de tierra, aunque los resultados son muy diversos -formal y conceptualmente- entre los distintos proyectos.

  7. EN LA RESIDENCIA EN LA TIERRA, UN “CABALLERO SOLO” VIVE POSEÍDO POR EL DESEO

    Directory of Open Access Journals (Sweden)

    Luis Alfonso Castro Sotelo

    2011-09-01

    Full Text Available A través del análisis textual, palabras clave, estructura, tema y perspectiva de la voz lírica, se pretende rescatar los elementos estéticos e ideológicos del poema "Caballero solo" del libro Residencia en la tierra. Se asume tal poema como evidencia de la transformación en el sistema nerudiano, un poema donde los elementos de lo social conviven y se enfrentan contra el sujeto individual que escribe y padece. En cierto modo, este poema propone una explicación tipo tesis sobre el funcionamiento del deseo, origen y tránsito, y la vida sexual del mundo social que rodea al poeta y que provoca el retorno posible al espacio primigenio del bosque, la naturaleza y los monstruos de la fantasía: después de percibir el sexo en todas partes, el poeta se protege y rodea por los elementos que lo acompañaron en la infancia y, tal vez, formaron parte del paisaje de todos los hombres a la hora del deseo y del sexo.In these pages, the poem "Caballero solo" is seen as a particularly rich discourse for textual analysis. The poem is built up around key words and concepts, an evocative structure, an attractive issue, and a thought provoking perspective, following an undoubtedly Nerudian lyric voice. The focus lies on the aesthetic and ideological elements in "Caballero solo", included in Residencia en la tierra. The poem is seen as evidence of a transformation in the Nerudian system, where the social elements coexist along with and confront the subject who writes and suffers. Emphasis is paid to the way the poem states a thesis regarding the functioning of desires, their origins and evolution, and sexuality in the social world of the poet, the subject. This world provides a possibility of returning to the primitive spaces of nature, the woods, and the monsters of fantasy. After having perceived sexuality everywhere, the poet shelters himself amongst the elements of his infancy, which can be taken as a common human landscape alluding to sex and desire.

  8. LA MOVILIZACIÓN DE LOS GARÍFUNAS PARA PRESERVAR SUS TIERRAS «ANCESTRALES» EN GUATEMALA

    Directory of Open Access Journals (Sweden)

    Nicolás Rey

    2009-12-01

    Full Text Available Livingston, en el noreste de Guatemala, es la «ciudad negra» de ese país que cuenta con una población de mayoría maya. Los derechos de los garífunas, mayas y xincas —recuperación de tierras ancestrales, valorización de su identidad y desarrollo socioeconómico— fueron inscritos en los Acuerdos de Paz, 1995-1996. Este artículo, resultado de una amplia investigación, presenta la increíble trayectoria de los garífunas: - un pueblo «en resistencia» nacido en las Antillas Menores, del encuentro entre indígenas caribes y negros cimarrones durante la colonización y la esclavitud; luego deportado a América Central, - que está reconquistando «espacios» como la tierra, lo político... gracias a una dinámica social compleja que une los vivos a los muertos —culto a los ancestros—, en alianza a veces con otros grupos mayas y ladinos.   ABSTRACT Livingston, in the northeast of Guatemala, is a «black city» in a country with a predominantly Maya population. The rights of the Garinagu, Maya and Xinca—the recovery of their ancestral lands, the value placed on their identity, and socio-economic development—were enshrined in the peace agreements (1995-1996. This article, resulting from an extensive research project, describes the incredible story of the Garinagu: - a people in «resistance» born in the Lesser Antilles from the encounter between Carib Indians and black runaway slaves, during colonization and slavery, later deported to Central America - who are reconquering «spaces» such as land and politics, thanks to a complex social dynamic that links those who are alive to the dead —ancestor worship—, occasionally in conjunction with other groups —Maya, Ladinos—.

  9. De la tierra al suelo: la transformación del paisaje y el nuevo turismo residencial

    Directory of Open Access Journals (Sweden)

    Aledo Tur, Antonio

    2008-02-01

    Full Text Available Residential Tourism has had a main role of speeding up the social and environmental processes of change that took place in Spain during the second half of the last century. This article begins with the description of its main characteristics, its effects at a local level and the different phases of its evolution. A special reference will be made with regard to last phase (2002-2007 which has been nomitaded New Residential Tourism (NRT. NRT is characterized by the appearance of urban megaprojects of thousands of households, with several golf courses and all the services needed. Its goal is to build privatized units of residential leisure, which are autonomous and independent from the territory where they are settled. In this paper there is an underlying reflection about the socio-cultural consequences of the transformation of agricultural land into urban land. A land that is definitely denatured and transformed into urban space for tourism consumption.El turismo residencial ha sido un agente acelerador de los procesos de transformación social y ambiental acaecidos en la España mediterránea durante la segunda mitad del siglo pasado. Este trabajo se inicia con la descripción de sus principales características, sus efectos a escala local y sus diferentes fases evolutivas. Se hará una especial referencia al último período que se ha iniciado en 2002 y que se ha denominado Nuevo Turismo Residencia (NTR. El NTR se caracteriza por la aparición de megaproyectos urbanísticos de miles de viviendas, con varios campos de golf y todos los servicios necesarios para convertirlo en una unidad de ocio residencial privatizada, autónoma e independiente del territorio en el que se instale. En última instancia, en este artículo subyace una reflexión en torno a las consecuencias socioculturales de la transformación de la tierra en suelo ya que éste es el principal recurso del turismo residencial. La tierra ha pasado de entenderse como un espacio para la

  10. CO2 and CH4 fluxes of contrasting pristine bogs in southern Patagonia (Tierra del Fuego, Argentina)

    Science.gov (United States)

    Münchberger, Wiebke; Blodau, Christian; Kleinebecker, Till; Pancotto, Veronica

    2015-04-01

    South Patagonian peatlands cover a wide range of the southern terrestrial area and thus are an important component of the terrestrial global carbon cycle. These extremely southern ecosystems have been accumulating organic material since the last glaciation up to now and are - in contrast to northern hemisphere bogs - virtually unaffected by human activities. So far, little attention has been given to these pristine ecosystems and great carbon reservoirs which will potentially be affected by climate change. We aim to fill the knowledge gap in the quantity of carbon released from these bogs and in what controls their fluxes. We study the temporal and spatial variability of carbon fluxes in two contrasting bog ecosystems in southern Patagonia, Tierra del Fuego. Sphagnum-dominated bog ecosystems in Tierra del Fuego are similar to the ones on the northern hemisphere, while cushion plant-dominated bogs can almost exclusively be found in southern Patagonia. These unique cushion plant-dominated bogs are found close to the coast and their occurrence changes gradually to Sphagnum-dominated bogs with increasing distance from the coast. We conduct closed chamber measurements and record relevant environmental variables for CO2 and CH4 fluxes during two austral vegetation periods from December to April. Chamber measurements are performed on microforms representing the main vegetation units of the studied bogs. Gas concentrations are measured with a fast analyzer (Los Gatos Ultraportable Greenhouse Gas Analyzer) allowing to accurately record CH4 fluxes in the ppm range. We present preliminary results of the carbon flux variability from south Patagonian peat bogs and give insights into their environmental controls. Carbon fluxes of these two bog types appear to be highly different. In contrast to Sphagnum-dominated bogs, cushion plant-dominated bogs release almost no CH4 while their CO2 flux in both, photosynthesis and respiration, can be twice as high as for Sphagnum

  11. Physiological Modeling of Responses to Upper vs Lower Lobe Lung Volume Reduction in Homogeneous Emphysema

    Directory of Open Access Journals (Sweden)

    Arschang eValipour

    2012-10-01

    Full Text Available Rationale: In clinical trials, homogeneous emphysema patients have responded well to upper lobe volume reduction but not lower lobe volume reduction. Materials/Methods: To understand the physiological basis for this observation, a computer model was developed to simulate the effects of upper and lower lobe lung volume reduction on RV/TLC and lung recoil in homogeneous emphysema.Results: Patients with homogeneous emphysema received either upper or lower lobe volume reduction therapy based on findings of radionucleotide scintigraphy scanning. CT analysis of lobar volumes showed that patients undergoing upper (n=18; -265 mL/site and lower lobe treatment (n=11; -217 mL/site experienced similar reductions in lung volume. However, only upper lobe treatment improved FEV1 (+11.1±14.7% vs -4.4±15.8% and RV/TLC (-5.4± 8.1% vs -2.4±8.6%. Model simulations provided an unexpected explanation for this response. Increases in transpulmonary pressure subsequent to volume reduction increased RV/TLC in upper lobe alveoli, while caudal shifts in airway closure decreased RV/TLC in lower lobe alveoli. Upper lobe treatment, which eliminates apical alveoli with high RV/TLC values, lowers the average RV/TLC of the lung. Conversely, lower lobe treatment, which eliminates caudal alveoli with low RV/TLC values, has less effect. Conclusions: Lower lobe treatment in homogeneous emphysema is uniformly less effective than upper lobe treatment.

  12. The Structural Plasticity of White Matter Networks Following Anterior Temporal Lobe Resection

    Science.gov (United States)

    Yogarajah, Mahinda; Focke, Niels K.; Bonelli, Silvia B.; Thompson, Pamela; Vollmar, Christian; McEvoy, Andrew W.; Alexander, Daniel C.; Symms, Mark R.; Koepp, Matthias J.; Duncan, John S.

    2010-01-01

    Anterior temporal lobe resection is an effective treatment for refractory temporal lobe epilepsy. The structural consequences of such surgery in the white matter, and how these relate to language function after surgery remain unknown. We carried out a longitudinal study with diffusion tensor imaging in 26 left and 20 right temporal lobe epilepsy…

  13. Experimental provocation of 'ice-cream headache' by ice cubes and ice water.

    Science.gov (United States)

    Mages, Stephan; Hensel, Ole; Zierz, Antonia Maria; Kraya, Torsten; Zierz, Stephan

    2017-04-01

    Background There are various studies on experimentally provoked 'ice-cream headache' or 'headache attributed to ingestion or inhalation of a cold stimulus' (HICS) using different provocation protocols. The aim of this study was to compare two provocation protocols. Methods Ice cubes pressed to the palate and fast ingestion of ice water were used to provoke HICS and clinical features were compared. Results The ice-water stimulus provoked HICS significantly more often than the ice-cube stimulus (9/77 vs. 39/77). Ice-water-provoked HICS had a significantly shorter latency (median 15 s, range 4-97 s vs. median 68 s, range 27-96 s). There was no difference in pain localisation. Character after ice-cube stimulation was predominantly described as pressing and after ice-water stimulation as stabbing. A second HICS followed in 10/39 (26%) of the headaches provoked by ice water. Lacrimation occurred significantly more often in volunteers with than in those without HICS. Discussion HICS provoked by ice water was more frequent, had a shorter latency, different pain character and higher pain intensity than HICS provoked by ice cubes. The finding of two subsequent HICS attacks in the same volunteers supports the notion that two types of HICS exist. Lacrimation during HICS indicates involvement of the trigeminal-autonomic reflex.

  14. GPR capabilities for ice thickness sampling of low salinity ice and for detecting oil in ice

    Energy Technology Data Exchange (ETDEWEB)

    Lalumiere, Louis [Sensors by Design Ltd. (Canada)

    2011-07-01

    This report discusses the performance and capabilities test of two airborne ground-penetrating radar (GPR) systems of the Bedford Institute of Oceanography (BIO), Noggin 1000 and Noggin 500, for monitoring low salinity snow and ice properties which was used to measure the thickness of brackish ice on Lake Melville in Labrador and on a tidal river in Prince Edward Island. The work of other researchers is documented and the measurement techniques proposed are compared to the actual GPR approach. Different plots of GPR data taken over snow and freshwater ice and over ice with changing salinity are discussed. An interpretation of brackish ice GPR plots done by the Noggin 1000 and Noggin 500 systems is given based on resolution criterion. Additionally, the capability of the BIO helicopter-borne GPR to detect oil-in-ice has been also investigated, and an opinion on the likelihood of the success of GPR as an oil-in-ice detector is given.

  15. Animals and ICE

    DEFF Research Database (Denmark)

    van Hemmen, J Leo; Christensen-Dalsgaard, Jakob; Carr, Catherine E

    2016-01-01

    experimental and mathematical foundation, it is known that there is a low-frequency regime where the internal time difference (iTD) as perceived by the animal may well be 2-5 times higher than the external ITD, the interaural time difference, and that there is a frequency plateau over which the fraction i......TD/ITD is constant. There is also a high-frequency regime where the internal level (amplitude) difference iLD as perceived by the animal is much higher than the interaural level difference ILD measured externally between the two ears. The fundamental tympanic frequency segregates the two regimes. The present special...... issue devoted to "internally coupled ears" provides an overview of many aspects of ICE, be they acoustic, anatomical, auditory, mathematical, or neurobiological. A focus is on the hotly debated topic of what aspects of ICE animals actually exploit neuronally to localize a sound source....

  16. Skating on slippery ice

    Directory of Open Access Journals (Sweden)

    J. M. J. van Leeuwen

    2017-12-01

    Full Text Available The friction of a stationary moving skate on smooth ice is investigated, in particular in relation to the formation of a thin layer of water between skate and ice. It is found that the combination of ploughing and sliding gives a friction force that is rather insensitive for parameters such as velocity and temperature. The weak dependence originates from the pressure adjustment inside the water layer. For instance, high velocities, which would give rise to high friction, also lead to large pressures, which, in turn, decrease the contact zone and so lower the friction. The theory is a combination and completion of two existing but conflicting theories on the formation of the water layer.

  17. Theory of amorphous ices.

    Science.gov (United States)

    Limmer, David T; Chandler, David

    2014-07-01

    We derive a phase diagram for amorphous solids and liquid supercooled water and explain why the amorphous solids of water exist in several different forms. Application of large-deviation theory allows us to prepare such phases in computer simulations. Along with nonequilibrium transitions between the ergodic liquid and two distinct amorphous solids, we establish coexistence between these two amorphous solids. The phase diagram we predict includes a nonequilibrium triple point where two amorphous phases and the liquid coexist. Whereas the amorphous solids are long-lived and slowly aging glasses, their melting can lead quickly to the formation of crystalline ice. Further, melting of the higher density amorphous solid at low pressures takes place in steps, transitioning to the lower-density glass before accessing a nonequilibrium liquid from which ice coarsens.

  18. Purificando la tierra, colonizando el espíritu: conflicto armado y religiosidad en la mítica Marquetalia

    Directory of Open Access Journals (Sweden)

    Andrés Felipe Ospina

    2015-01-01

    Full Text Available El quebrado territorio de la cordillera central en Colombia ha sido el epicentrode luchas políticas, militares y especialmente espirituales en las que el territorioen pugna, la mítica zona de Marquetalia, debate creencias y prácticas, en torno alpoder, la sangre y la tierra. Lógicas de diverso orden que vinculan la lucha armada,la conquista espiritual y la cosmología del pueblo indígena Nasa –que habita en lazona–, ponen acento crítico en una tensa relación que confronta a la vez que vinculael orden político con el actuar religioso. Este trabajo, centrado en las relacionesemergentes de un campo etnográfico, busca dar cuenta de acciones y relaciones quearticulan y condensan tales enfrentamientos, al mismo tiempo que sugiere un marcode interpretación desde las prácticas religiosas que evidencia la forma en que varioselementos del conflicto armado en Colombia tienen como móvil un componenteespiritual.

  19. Martín Sancho (siglos XIV-XVI un despoblado bajomedieval en la tierra de Medellín

    Directory of Open Access Journals (Sweden)

    Julián Clemente Ramos

    2006-08-01

    Full Text Available The Extremaduran village of Martin Sancho is documented for the first time in 1374. In the second half of the fourteenth century, something that may initially have been an individual appropriation has given rise to a concentrated settlement. Its population seems never to have been more than twenty-five. This village had its own district and council, whose only official was the mayor. Its inhabitants were parishioners of the church of San Martin de Medellín. Around the middle of the fifteenth century, Martin Sancho experienced a certain demographic decline, its population no more than 15-20, of whom only a part resided there permanently. This situation appears to have increased the importance of cattle raising, in the context of the relative abundance of grasses and perhaps also the accumulation of properties on the part of qualified members of the village. The violence of the governor of the tierra and future landlord Rodrigo Portocarrero, who appropriates the district, produces rapid depopulation. In the first quarter of the sixteenth century, Medellín manages through a judicial process to integrate it in its public land.

  20. La restitución de la tierra y la prevención del desplazamiento forzado en Colombia

    Directory of Open Access Journals (Sweden)

    Felipe Gómez-Isa

    2010-12-01

    Full Text Available El conflicto armado interno en Colombia se caracteriza por la generación de más de tres millones de desplazados internos, con consecuencias dramáticas desde el punto de vista humanitario y desde la óptica de la protección de sus derechos. En ocasiones, las razones fundamentales de dicho desplazamiento descansan en una dinámica de control y apropiación territorial con fines tanto estratégico-militares como puramente económicos. Los estándares jurídicos de orden interno e internacional establecen el derecho de las víctimas a la restitución de sus viviendas y patrimonio como el “medio preferente” de reparación en casos de desplazamiento, algo que no se está teniendo en cuenta suficientemente por parte de las políticas de atención al desplazamiento del Gobierno colombiano y de diversas instituciones internacionales. Cualquier política integral de reparación a las víctimas debe pasar necesariamente por la reversión del despojo de tierras, territorios y bienes que se ha producido en Colombia al amparo del conflicto armado interno.

  1. Pedagogía de la Tierra: los sujetos del campo y la Enseñanza Superior

    Directory of Open Access Journals (Sweden)

    Fernando José Martins

    2013-07-01

    Full Text Available Resumen: En el contexto de las políticas y prácticas de la enseñanza superior, de manera general, cada vez más atraídas por la lógica de mercado, se intenta en este artículo dar visibilidad a una experiencia en este nivel de enseñanza, que pretende posicionarse en la contracorriente de aquella lógica: la Pedagogía de la Tierra. Bajo la forma de política pública afirmativa, encarada hacia los sujetos del campo, se construye en Brasil un curso especial con características singulares y propias, que ha llamado la atención de los investigadores y de la sociedad civil. Esta experiencia señala elementos significativos que sustentan la definición de políticas y prácticas de una enseñanza superior vinculada a una perspectiva emancipatoria, orientada específicamente a las clases populares. Palabras clave: movimientos sociales, participación, universidad.

  2. La arquitectura de los puestos de pastoreo en las tierras altas del norte argentino (Susques, provincia de Jujuy

    Directory of Open Access Journals (Sweden)

    Jorge Tomasi

    2015-06-01

    Full Text Available En este artículo nos proponemos analizar las características que presentan los puestos de pastoreo en las tierras altas de la provincia de Jujuy, en el noroeste argentino. El análisis considerará las lógicas de emplazamiento, las configuraciones y las materialidades de estos puestos. Tomaremos en cuenta particularmente los sentidos que la topografía tiene en la configuración de la arquitectura doméstica. Estas construcciones tienen un sentido específico en el marco de los sistemas de asentamiento de los grupos pastoriles, en relación con las estrategias de movilidad de las familias junto con los rebaños. El estudio se basa en el material del trabajo de campo etnográfico que se ha venido desarrollando desde el 2004 en la localidad de Susques, el cual ha implicado un relevamiento sistemático de los distintos tipos de asentamiento, en el marco de una investigación sobre las espacialidades y la arquitectura pastoril en los Andes.

  3. Salamanca como referente simbólico: la urbe del siglo XXI en Tierra Violenta de Luciano G. Egido

    Directory of Open Access Journals (Sweden)

    Ana Eva Rodríguez Valentín

    2017-02-01

    Full Text Available El propósito de este artículo es examinar el material simbólico y los vínculos sociales entre la memoria colectiva, la identidad y el espacio de Salamanca, en el siglo XXI a través de la novela, Tierra Violenta, de Luciano G. Egido. Desde esta perspectiva, propongo una lectura del texto que nos ayude a entender cómo las circunstancias políticas y económicas determinan la estructura de la ciudad; que cambia, a su vez,  la vida de sus habitantes. Se trata de una ciudad que, aparentemente, vive en el pasado, pero que no es inmune a los mecanismos que rigen el siglo XXI. En esta aproximación, el texto literario es una fuente de distintas líneas de análisis para entender las temporalidades urbanas y la dialéctica de ambos, el proyecto público y  la herencia urbana.

  4. El arbitrio de tierras de 1622 y el debate sobre las propiedades y los derechos coloniales de los indios

    Directory of Open Access Journals (Sweden)

    Glave, Luis Miguel

    2014-06-01

    Full Text Available This article analyses the 1622 tax on the sale of lands within the context of the broad debate regarding the lawfulness of the sale and composition of properties, initiated at the end of the sixteenth century. The opportunity to press upon the natives’ resources is studied, as well as the defensive measures available to them, while striving to call attention to the dialogue between metropolitan policy – which sought to increase monetary resources in times of need – and discrepancies within the Andean kingdom at a time of legal and administrative changes that attempted to respond to imperial demands.Este artículo analiza un arbitrio sobre la venta de tierras de 1622, situándolo en el extenso debate acerca de la licitud de la enajenación y composición de propiedades comenzado a finales del siglo XVI. Se estudia la coyuntura de presión sobre los recursos de los naturales y las opciones de defensa de los mismos, procurando resaltar el diálogo entre la política metropolitana, que buscaba ampliar recursos monetarios en tiempo de necesidad, y las discrepancias internas del reino andino en pleno proceso de cambios administrativos y legales que intentaban responder a esa demanda imperial.

  5. «En tierra de hombres» (2005. El acoso psicológico en el trabajo

    Directory of Open Access Journals (Sweden)

    Carmen María VIZOSO GÓMEZ

    2016-10-01

    Full Text Available El acoso psicológico en el trabajo está considerado un grave problema en el entorno laboral debido a los efectos negativos que provoca no solo en la convivencia dentro de la empresa y en la productividad de los trabajadores sino también en la salud de la víctima y en el bienestar de su familia. La película En tierra de hombres está inspirada en un caso real de acoso en el trabajo, concretamente de acoso sexual, sufrido por las mujeres que trabajaban en una mina de hierro. Esta situación desembocó en la primera demanda colectiva sobre discriminación sexual. En el presente artículo se analizan las escenas, los diálogos y las características de los personajes para explicar en qué consiste este tipo de acoso. Así, se describe el clima laboral en la empresa, las conductas vejatorias de los acosadores, el proceso de desarrollo del problema hasta que la víctima abandona la empresa, las consecuencias del acoso en diversos ámbitos y también una posible forma de solucionarlo. Por último, se defiende el valor que tiene este film como recurso didáctico para la formación de estudiantes y trabajadores y para la prevención del acoso en el ámbito laboral.

  6. Edipo y Gaia : el tema de la Madre Tierra en el Oráculo de Delfos

    Directory of Open Access Journals (Sweden)

    Ángel Luis Casquillo Fumanal

    2010-01-01

    Full Text Available Cuando el oráculo de Delfos proclamó destino de Edipo el casarse con su madre, éste entendió de forma unívoca que la Pitia se refería a su madre biológica. Pero la equivocidad (y la analogía era una característica propia de Delfos, que empleaba conceptos —como el de madre— de forma ambigua: El término madre en la ideología délfica podía referirse analógicamente a la Madre Tierra. Si Edipo hubiera entendido el oráculo de forma analógica, su destino podría haber sido distinto.When Delphic oracle proclaimed Oedipus;destiny marrying his own mother, he understood in an univocal way that Pythia meant his biological mother. But aequivocity (or analogy was characteristic of Delphi, which employed concepts —as mother— in an ambiguous way. The word mother, in Delphic ideology, could mean Mother Earth. If Oedipus had understood Delphic oracle in an analogical way, his destiny could have been different.

  7. Arctic Ice Studies

    Science.gov (United States)

    1993-02-01

    i heoriotlscale wace s 50 kin wthe11 aii vertical leadi tof M o.ChrlesA Lcur the siir-ai’.orc~5 . ~ ~G. RLI Lt(lWA~S II I Shuchln P A P Ut alI 9...can be utilized msccesafully. distinguish between these two major ice types and open I. INTRODUCTION water. S THE geophysical and economic importance of

  8. Car engine breather icing

    OpenAIRE

    Horoufi, Aryan

    2012-01-01

    Icing in an engine breather system can block the engine breather pipe, cause excessive crankcase pressure and degrade the engine performance. In this project, a numerical study, experimental tests and CFD analysis are employed in order to understand condensation and the extent of freezing inside a vertical pipe, a horizontal pipe and a T-joint pipe which are exposed to an external convective cooling. The pipe internal flow is assumed to be a vapour/air mixture. This study has l...

  9. Marginal Ice Zone Bibliography.

    Science.gov (United States)

    1985-06-01

    Tsunamis, Gravimetry , Earth Tides, World Data Center A: Oceanography Recent Movements of the Earth’s National Oceanographic Data Center Crust...sufficiently low, the dissolved salts precipitate out in the form of solid hydrates. It has been proposed that these solid hydrates add to the overall...strength of the ice. The first salt hydrate to precipitate should be that of sodium sul- * fate, Na2SO4IOH2O (the sulfate ion is the second most

  10. A review on late Paleozoic ice-related erosional landforms in the Paraná Basin: origin and paleogeographical implications

    Directory of Open Access Journals (Sweden)

    Eduardo Luiz Menozzo da Rosa

    Full Text Available ABSTRACT: The Late Paleozoic Ice Age is recorded in the Paraná Basin as glacial deposits, deformational features and ice-related erosional landforms of the Itararé Group. Erosional landforms are often employed to build paleogeographic models that depict the location of ice masses and paleo ice-flow directions. This paper provides a review of the literature and new data on micro- to meso-scale ice-related, erosional landforms of the Paraná Basin. Examined landforms can be placed into four broad categories based on their mode of origin. Subglacial landforms on rigid substrates occur on the Precambrian basement or on older units in the Paraná Basin. They include streamlined landforms and striated pavements formed by abrasion and/or plucking beneath advancing glaciers. Subglacial landforms on soft beds are intraformational surfaces generated by erosion and deformation of unconsolidated deposits when overridden by glaciers. Ice-keel scour marks are soft-sediment striated/grooved landforms developed by the scouring of free-floating ice masses on underlying sediments. Striated clast pavements are horizons containing aligned clasts that are abraded subglacially due to the advance of glaciers on unconsolidated deposits. Only those erosional landforms formed subglacially can be used as reliable paleo ice-flow indicators. Based on these data, the paleogeography of the Paraná Basin during the Late Paleozoic Ice Age fits into a model of several glacial lobes derived from topographically-controlled ice spreading centers located around the basin instead of a single continental ice sheet.

  11. Ice condenser experimental plan

    International Nuclear Information System (INIS)

    Kannberg, L.D.; Piepel, G.F.; Owczarski, P.C.; Liebetrau, A.M.

    1986-01-01

    An experimental plan is being developed to validate the computer code ICEDF. The code was developed to estimate the extent of aerosol retention in the ice compartments of pressurized water reactor ice condenser containment systems during severe accidents. The development of the experimental plan began with review of available information on the conditions under which the code will be applied. Computer-generated estimates of thermohydraulic and aerosol conditions entering the ice condenser were evaluated and along with other information, used to generate design criteria. The design criteria have been used for preliminary test assembly design and for generation of statistical test designs. Consideration of the phenomena to be evaluated in the testing program, as well as equipment and measurement limitations, have led to changes in the design criteria and to subsequent changes in the test assembly design and statistical test design. The overall strategy in developing the experimental plan includes iterative generation and evaluation of candidate test designs using computer codes for statistical test design and ICEDF for estimation of experimental results. Estimates of experimental variability made prior to actual testing will be verified by replicate testing at preselected design points

  12. Visual interhemispheric communication and callosal connections of the occipital lobes.

    Science.gov (United States)

    Berlucchi, Giovanni

    2014-07-01

    Callosal connections of the occipital lobes, coursing in the splenium of the corpus callosum, have long been thought to be crucial for interactions between the cerebral hemispheres in vision in both experimental animals and humans. Yet the callosal connections of the temporal and parietal lobes appear to have more important roles than those of the occipital callosal connections in at least some high-order interhemispheric visual functions. The partial intermixing and overlap of temporal, parietal and occipital callosal connections within the splenium has made it difficult to attribute the effects of splenial pathological lesions or experimental sections to splenial components specifically related to select cortical areas. The present review describes some current contributions from the modern techniques for the tracking of commissural fibers within the living human brain to the tentative assignation of specific visual functions to specific callosal tracts, either occipital or extraoccipital. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Occipital lobe epilepsy with fear as leading ictal symptom.

    Science.gov (United States)

    Oehl, Bernhard; Schulze-Bonhage, Andreas; Lanz, Michael; Brandt, Armin; Altenmüller, Dirk-Matthias

    2012-03-01

    Ictal fear is a semiological feature which is commonly associated with mesial temporal lobe epilepsy. Here, we describe fear as a leading symptom in cryptogenic occipital lobe epilepsy. In a patient with negative MRI findings, intracranial EEG recordings documented a strict correlation between habitual ictal anxiety attacks and both spontaneous and stimulation-induced epileptic activity in a right occipital epileptogenic area with subsequent spreading to the symptomatogenic zone in the amygdala. Circumscribed occipital topectomy led to seizure freedom. Episodes of non-epileptic fear ceased shortly afterwards. This report provides insight into pathways of propagation of epileptic activity, illustrates different etiologies of pathologic fear and underlines the importance of ictal EEG recordings. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Pulmonary sequestrations of the upper lobe in children: Three presentations

    International Nuclear Information System (INIS)

    Hoeffel, J.C.; Bernard, C.; Didier, F.; Bretagne, M.C.; Gautry, P.; Olive, D.; Prevot, J.; Pernot, C.; Hopital des Enfants, 54 - Vandoeuvre-les-Nancy; Hopital des Enfants, 54 - Vandoeuvre-les-Nancy; Hopital des Enfants, 54 - Vandoeuvre-les-Nancy

    1986-01-01

    Pulmonary sequestrations are congenital abnormalities where nonfunctioning lung tissue receives its vascular supply from the systemic circulation (thoracic or abdominal aorta). It is necessary to establish the diagnosis in childhood when the lesions are uncomplicated. The authors present three cases of sequestration of the apex (2 extralobar and 1 atypical) with the main clinical and radiological features. Sequestrations in the upper lobe are rare, and the usual site is the left lower lobe. Plain X-rays show a dense opacity, sometimes with an air-fluid level: angiography is currently the best mean for definitive diagnosis; however, computed tomography will probably be very useful in the future. Differential diagnosis includes tumours of the superior mediastinum (neurogenic tumours, digestive duplication, bronchogenic cysts, pheochromocytoma and hydatid cysts). (orig.) [de

  15. Abscess of residual lobe after pulmonary resection for lung cancer.

    Science.gov (United States)

    Ligabue, Tommaso; Voltolini, Luca; Ghiribelli, Claudia; Luzzi, Luca; Rapicetta, Cristian; Gotti, Giuseppe

    2008-04-01

    Abscess of the residual lobe after lobectomy is a rare but potentially lethal complication. Between January 1975 and December 2006, 1,460 patients underwent elective pulmonary lobectomy for non-small-cell lung cancer at our institution. Abscess of the residual lung parenchyma occurred in 5 (0.3%) cases (4 bilobectomies and 1 lobectomy). Postoperative chest radiography showed incomplete expansion and consolidation of residual lung parenchyma. Flexible bronchoscopy revealed persistent bronchial occlusion from purulent secretions and/or bronchial collapse. Computed tomography in 3 patients demonstrated lung abscess foci. Surgical treatment included completion right pneumonectomy in 3 patients and a middle lobectomy in one. Complications after repeat thoracotomy comprised contralateral pneumonia and sepsis in 1 patient. Residual lobar abscess after lobectomy should be suspected in patients presenting with fever, leukocytosis, bronchial obstruction and lung consolidation despite antibiotic therapy, physiotherapy and bronchoscopy. Computed tomography is mandatory for early diagnosis. Surgical resection of the affected lobe is recommended.

  16. Amusia After Right Temporoparietal Lobe Infarction: A Case Report.

    Science.gov (United States)

    Yoo, Hyun-Joon; Moon, Hyun Im; Pyun, Sung-Bom

    2016-10-01

    Which brain regions participate in musical processing remains controversial. During singing and listening a familiar song, it is necessary to retrieve information from the long-term memory. However, the precise mechanism involved in musical processing is unclear. Amusia is impaired perception, understanding, or production of music not attributable to disease of the peripheral auditory pathways or motor system. We report a case of a 36-year-old right-handed man who lost the ability to discriminate or reproduce rhythms after a right temporoparietal lobe infarction. We diagnosed him as an amusic patient using the online version of Montreal Battery of Evaluation of Amusia (MBEA). This case report suggests that amusia could appear after right temporoparietal lobe infarction. Further research is needed to elucidate the dynamic musical processing mechanism and its associated neural structures.

  17. Bilingualism Alters Children's Frontal Lobe Functioning for Attentional Control

    Science.gov (United States)

    Arredondo, Maria M.; Hu, Xiao-Su; Satterfield, Teresa; Kovelman, Ioulia

    2017-01-01

    Bilingualism is a typical linguistic experience, yet relatively little is known about its impact on children's cognitive and brain development. Theories of bilingualism suggest early dual-language acquisition can improve children's cognitive abilities, specifically those relying on frontal lobe functioning. While behavioral findings present much conflicting evidence, little is known about its effects on children's frontal lobe development. Using functional Near-Infrared Spectroscopy (fNIRS), the findings suggest that Spanish-English bilingual children (n=13, ages 7-13) had greater activation in left prefrontal cortex during a non-verbal attentional control task relative to age-matched English monolinguals. In contrast, monolinguals (n=14) showed greater right prefrontal activation than bilinguals. The present findings suggest early bilingualism yields significant changes to the functional organization of children's prefrontal cortex for attentional control and carry implications for understanding how early life experiences impact cognition and brain development. PMID:26743118

  18. Frontal lobe epilepsy may present as myoclonic seizures.

    Science.gov (United States)

    Cho, Yong Won; Yi, Sang Doe; Motamedi, Gholam K

    2010-04-01

    We describe a patient with seizures arising from right anterior-inferior frontal lobe presenting as myoclonic epilepsy. A 19-year-old man had experienced frequent paroxysmal bilateral myoclonic jerks involving his upper arms, shoulders, neck, and upper trunk since the age of 10. His baseline EEG showed intermittent right frontal spikes, and his ictal EEG showed rhythmic sharp theta discharges in the same area. MRI revealed cortical dysplasia in the right inferior frontal gyrus, and ictal-interictal SPECT analysis by SPM showed increased signal abnormality in this region. Diffusion tensor imaging (DTI) showed defects in fasciculi in the same area. These findings suggest that frontal lobe epilepsy should be considered in some patients with myoclonic seizures. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  19. Acute Infantile Encephalopathy Predominantly Affecting The Frontal Lobes (AIEF).

    Science.gov (United States)

    Raha, Sarbani; Udani, Vrajesh

    2012-12-01

    Acute Infantile Encephalopathy Predominantly Affecting the Frontal Lobes (AIEF) is a relatively recent described entity. This article includes case reports of two patients who had bifrontal involvement during acute febrile encephalopathy. Case 1 describes a 1-y-old boy who presented with hyperpyrexia and dialeptic seizures. Imaging revealed significant bilateral frontal lobe involvement while serology proved presence of Influenza B infection. Over a period of one wk, he recovered with significant cognitive decline and perseveratory behavior. Another 6-y-old boy presented with language and behavioral problems suggestive of frontal dysfunction after recovering from prolonged impairment of consciousness following a convulsive status epilepticus. Bilateral superior frontal lesions with gyral swelling was evident on neuroimaging. These cases are among the very few cases of AIEF described in recent literature and the article also reviews this unique subtype of acute encephalopathy.

  20. Using ice melting and ice rolling technologies to remove ice from sub-transmission and transmission lines at Manitoba Hydro

    International Nuclear Information System (INIS)

    Farias, A. R.

    1999-01-01

    Development of an of an Ice Storm Management program by Manitoba Hydro to reduce ice storm damage to its 8 kV feeders to 115 kV transmission lines, is discussed. The program consists of the de-icing of overhead lines, either by ice melting, or ice rolling. Ice melting involves the placement of a three-phase short at a calculated point. The term ice rolling denotes a process of mechanically stripping the ice from conductors. The most recent major ice storm experienced by Manitoba Hydro was in the winter of 1997/1998. During the period from February 6 to February 17, 1998, a total of 83 'ice melt' procedures were performed to melt the ice from 2,628 km of overhead line (7,883 km of conductor), in addition to 'ice rolling'. This paper describes Manitoba Hydro's 25-years' experience with ice melting and it also describes the advantages and disadvantages of both ice melting and ice rolling. Although not a panacea to combat the effects of ice storms, ice melting was found to be the most effective way of removing ice from overhead transmission and sub-transmission lines. Ice rolling was also found to be effective. Other tools that have been found to be useful by various utilities in combating ice storm damage include improved structure and line design, system design that provide more redundancies and emergency sources, and standby generators at critical load points

  1. The lateralising significance of hypergraphia in temporal lobe epilepsy

    OpenAIRE

    Roberts, JKA; Robertson, MM; Trimble, MR

    1982-01-01

    Six patients with hypergraphia and epilepsy are presented and their clinical features compared with other patients reported in the literature. It is suggested that hypergraphia occurs more frequently in patients with right-sided non-dominant temporal lobe lesions, in contrast for example to the schizophreniform presentation of left-sided lesions. Other features of psychopathology possibly associated with non-dominant lesions, including elation, hypereligiosity and déjà vu experiences, are als...

  2. Neurobehavioral Management of Behavioral Anomalies in Frontal Lobe Syndrome

    OpenAIRE

    Malhotra, Shahzadi; Rajender, Gaurav; Sharma, Vibha; Singh, Tej Bahadur

    2009-01-01

    Neurobehavioral approach uses behavioral paradigm towards comprehensive rehabilitation by identifying the neurological or neuropsychological constraints that can interfere with learning and behavior of an individual. The present case study highlights the role of functional skills approach in neurobehavioral management towards cognitive rehabilitation to manage behavioral deficits in a 55-year-old man with nicotine dependence having frontal lobe lesions owing to gliosis of fronto-temporal brai...

  3. Olfactory Information Processing in the Drosophila Antennal Lobe : Anything Goes?

    OpenAIRE

    Silbering, Ana F.; Okada, Ryuichi; Ito, Kei; Galizia, Cosmas Giovanni

    2008-01-01

    When an animal smells an odor, olfactory sensory neurons generate an activity pattern across olfactory glomeruli of the first sensory neuropil, the insect antennal lobe or the vertebrate olfactory bulb. Here, several networks of local neurons interact with sensory neurons and with output neurons-insect projection neurons, or vertebrate mitral/tufted cells. The extent and form of information processing taking place in these local networks has been subject of controversy. To investigate the ro...

  4. Childhood allergic bronchopulmonary aspergillosis presenting as a middle lobe syndrome

    OpenAIRE

    Shah, Ashok; Gera, Kamal; Panjabi, Chandramani

    2016-01-01

    Allergic bronchopulmonary aspergillosis (ABPA) is infrequently documented in children with asthma. Although collapse is not uncommon, middle lobe syndrome (MLS) as a presentation of ABPA is rather a rarity. A 9-year-old female child with asthma presented with increase in intensity of symptoms along with a right midzone patchy consolidation on a chest radiograph. In addition, an ill-defined opacity abutting the right cardiac border with loss of cardiac silhouette was noted. A right lateral vie...

  5. Temporal lobe deficits in murderers: EEG findings undetected by PET.

    Science.gov (United States)

    Gatzke-Kopp, L M; Raine, A; Buchsbaum, M; LaCasse, L

    2001-01-01

    This study evaluates electroencephalography (EEG) and positron emission tomography (PET) in the same subjects. Fourteen murderers were assessed by using both PET (while they were performing the continuous performance task) and EEG during a resting state. EEG revealed significant increases in slow-wave activity in the temporal, but not frontal, lobe in murderers, in contrast to prior PET findings that showed reduced prefrontal, but not temporal, glucose metabolism. Results suggest that resting EEG shows empirical utility distinct from PET activation findings.

  6. Frontal Lobe Tuberculoma: A Clinical and Imaging Challenge

    OpenAIRE

    Alemayehu, Tinsae; Ergete, Wondwossen; Abebe, Workeabeba

    2017-01-01

    Background Pediatric nervous system tuberculomas are usually infra-tentorial and multiple. A frontal lobe location is rare. Case Details We report a 10 year-old boy who presented with a chronic headache and episodes of loss of consciousness. He had no signs of primary pulmonary tuberculosis and a diagnosis of frontal tuberculoma was made upon a post-operative biopsy. He improved following treatment with anti-tubercular drugs. Conclusion Tuberculosis should be considered in children with a chr...

  7. IceCube systematic errors investigation: Simulation of the ice

    Energy Technology Data Exchange (ETDEWEB)

    Resconi, Elisa; Wolf, Martin [Max-Planck-Institute for Nuclear Physics, Heidelberg (Germany); Schukraft, Anne [RWTH, Aachen University (Germany)

    2010-07-01

    IceCube is a neutrino observatory for astroparticle and astronomy research at the South Pole. It uses one cubic kilometer of Antartica's deepest ice (1500 m-2500 m in depth) to detect Cherenkov light, generated by charged particles traveling through the ice, with an array of phototubes encapsulated in glass pressure spheres. The arrival time as well as the charge deposited of the detected photons represent the base measurements that are used for track and energy reconstruction of those charged particles. The optical properties of the deep antarctic ice vary from layer to layer. Measurements of the ice properties and their correct modeling in Monte Carlo simulation is then of primary importance for the correct understanding of the IceCube telescope behavior. After a short summary about the different methods to investigate the ice properties and to calibrate the detector, we show how the simulation obtained by using this information compares to the measured data and how systematic errors due to uncertain ice properties are determined in IceCube.

  8. Medial temporal lobe damage impairs representation of simple stimuli

    Directory of Open Access Journals (Sweden)

    David E Warren

    2010-05-01

    Full Text Available Medial temporal lobe damage in humans is typically thought to produce a circumscribed impairment in the acquisition of new enduring memories, but recent reports have documented deficits even in short-term maintenance. We examined possible maintenance deficits in a population of medial temporal lobe amnesics, with the goal of characterizing their impairments as either representational drift or outright loss of representation over time. Patients and healthy comparisons performed a visual search task in which the similarity of various lures to a target was varied parametrically. Stimuli were simple shapes varying along one of several visual dimensions. The task was performed in two conditions, one presenting a sample target simultaneously with the search array and the other imposing a delay between sample and array. Eye-movement data collected during search revealed that the duration of fixations to items varied with lure-target similarity for all participants, i.e., fixations were longer for items more similar to the target. In the simultaneous condition, patients and comparisons exhibited an equivalent effect of similarity on fixation durations. However, imposing a delay modulated the effect differently for the two groups: in comparisons, fixation duration to similar items was exaggerated; in patients, the original effect was diminished. These findings indicate that medial temporal lobe lesions subtly impair short-term maintenance of even simple stimuli, with performance reflecting not the complete loss of the maintained representation but rather a degradation or progressive drift of the representation over time.

  9. Decreased astroglial monocarboxylate transporter 4 expression in temporal lobe epilepsy.

    Science.gov (United States)

    Liu, Bei; Niu, Le; Shen, Ming-Zhi; Gao, Lei; Wang, Chao; Li, Jie; Song, Li-Jia; Tao, Ye; Meng, Qiang; Yang, Qian-Li; Gao, Guo-Dong; Zhang, Hua

    2014-10-01

    Efflux of monocaroxylates like lactate, pyruvate, and ketone bodies from astrocytes through monocarboxylate transporter 4 (MCT4) supplies the local neuron population with metabolic intermediates to meet energy requirements under conditions of increased demand. Disruption of this astroglial-neuron metabolic coupling pathway may contribute to epileptogenesis. We measured MCT4 expression in temporal lobe epileptic foci excised from patients with intractable epilepsy and in rats injected with pilocarpine, an animal model of temporal lobe epilepsy (TLE). Cortical MCT4 expression levels were significantly lower in TLE patients compared with controls, due at least partially to MCT4 promoter methylation. Expression of MCT4 also decreased progressively in pilocarpine-treated rats from 12 h to 14 days post-administration. Underexpression of MCT4 in cultured astrocytes induced by a short hairpin RNA promoted apoptosis. Knockdown of astrocyte MCT4 also suppressed excitatory amino acid transporter 1 (EAAT1) expression. Reduced MCT4 and EAAT1 expression by astrocytes may lead to neuronal hyperexcitability and epileptogenesis in the temporal lobe by reducing the supply of metabolic intermediates and by allowing accumulation of extracellular glutamate.

  10. MRI lesion and epileptogenic focus in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Matsuda, Kazumi; Yagi, Kazuichi; Mihara, Tadahiro; Tottori, Takayasu; Watanabe, Yutaka; Seino, Masakazu

    1989-01-01

    The spatial relationship between a circumscribed lesion in the temporal lobe detected by MRI and an epileptogenic focus identified by ictal depth EEG along with a correlation of the MRI lesion with neuropathological findings were investigated in patients with medically intractable temporal lobe epilepsy but without any focal lesion on CT. Four parameters (an areal ratio of the temporal lobe against the hemisphere, area and calculated T1, T2 values of the hippocampus) were used to determine the abnormal MRI side. An agreement was reached in 67-72% of 18 patients between the abnormal values of the hippocampal area and of calculated T1, T2 and the side of the epileptogenic focus. In 14 of 17 patients, typical hippocampal sclerosis was demonstrated in resected tissue in accordance with the MRI lesions (atrophy and/or prolonged T2 of hippocampus). These results imply: 1)MRI abnormality thus defined may, if not all, indicate the side of the epileptogenic focus, and 2)also the presence of hippocampal sclerosis. It was emphasized that the MRI lesion would be a usable instrument to explore the causal relationship of hippocampal sclerosis to a generation of epileptogenic lesions as well as for presurgical evalution. (author)

  11. Emotional reactions in patients after frontal lobe stroke.

    Science.gov (United States)

    Stojanović, Zlatan; Stojanović, Sanja Vukadinović

    2015-09-01

    Emotional reactions have been documented after tumor lesions and the other damages of the brain. The aim of this paper was to examine the correlation between frontal lobe lesions and emotional reactions in patients with stroke. The research included 118 patients after stroke. Lesion localization was defined on computed axial tomography records, whereas the area and perimeter of lesion were measured by AutoCAD 2004 software. Examinations by means of the Hamilton Rating Scale for Anxiety and Depression (HRSA and HRSD) were carried out 11-40 days after stroke. Statistic data were processed by simple linear/nonlinear regression, Cox's and the generalized linear model. A higher frequency of emotional reactions, i.e. anxiety, was determined in women after stroke (p = 0.024). A negative correlation between the lesion size and the intensity of anxiety manifestations was determined (Spearman's r = -0.297; p = 0.001). Anxiety was more frequent in patients with frontal lobe lesions in the dominant hemisphere (interaction: frontal lesion * hand dominant hemisphere, p = 0.017). Also, HRSD score values showed the tendency for lesser decline in case of greater frontal lobe lesions in relation to lesions of other regions of prosencephalon (interaction: frontal lesion * lesion area, p = 0.001). The results of this study indicate the correlation between evolutionary younger structures of the central nervous system and emotional reactions of man. Therefore, it is necessary to undertake proper early psychopharmacotherapy in the vulnerable group of patients.

  12. The evolution of Sf. Gheorghe (Danube asymmetric deltaic lobe

    Directory of Open Access Journals (Sweden)

    Alfred VESPREMEANU-STROE

    2014-11-01

    Full Text Available The wave asymmetric Sf. Gheorghe lobe is the only active in the Danube delta where river mouth bar (and the associated barrier islands and spits continuously deployed a cyclic development for almost two millennia. During first stage, the Sf. Gheorghe distributary had a small discharge (with an order of magnitude lower than present which after that experienced a rapid increase in consequence of the successive avulsions of Împuţita (southern distributary of Sulina arm and Dunavăţ distributaries. Our morphological analyses together with the newly obtained chronology, revealed the multiple ridgesets structure of Sf. Gheorghe deltaic lobe. In fact, all ridgesets (10 follow a common morphodynamic pattern characterized by the cyclic succession of three stages: i subaqueous mouth bar development, ii barrier island emergence, iii barrier spit phase with several secondary spits derived from an updrift trunk ridge. The size of each ridgeset increased exponentially with every new cycle due to the constant lengthening of the coastline as the downdrift side of the lobe advances seaward through a series of progressively larger similar quadrilaterals, yielding to a constant enlargment of the delta front size. 

  13. The secondary lobe as anatomic landmark for different pulmonary diseases

    International Nuclear Information System (INIS)

    Spina, Juan C.; Spina, Juan C. h; Rolnik, Maria C.; Lema, Carlos; Venditi, Julio; Magarinos, Gabriel

    2002-01-01

    The objective of this paper is to present the spectrum of pathological findings in the pulmonary parenchyma, based on the knowledge of the secondary lobe and its components. The evaluation was made using high-resolution computed tomography (HRCT) and compared with the histopathological findings. By definition, the secondary lobe is the small portion of pulmonary tissue separated by septa of connective tissue and supplied by 2-5 or more terminal bronchioles according to their central or peripheral location. Different disorders may become evident as a consequence of : 1) Bronchiolar obstruction (transient or definitive); 2) Intra-alveolar or wall involvement; 3) Involvement of the support tissue; 4) Involvement of the vascular or lymphatic structures. The etiology may be idiopathic, infectious, due to inhalation, neoplastic, allergic, due to collagen diseases, secondary to drug administration and/or post-transplantation. The evaluation of the secondary lobe components, with fine section HRCT, is the dynamic method of choice for the characterisation of pulmonary diseases, and allows to perform earlier and more precise differential diagnoses, when correlated with the clinical findings. The addition of sections during expiration to the routine study is paramount to underscore perfusion disturbances, which may remain undiagnosed during deep inspiration. The goal of this study is to review some of these disorders in which HRCT may be very useful and to correlate our observations with the histopathological findings. (author)

  14. Explicit memory and implicit memory in occipital lobe stroke patients.

    Science.gov (United States)

    Gong, Liang; Wang, JiHua; Feng, Lei; Wang, MeiHong; Li, Xiu; Hu, JiaYun; Wang, Kai

    2015-03-01

    Occipital stroke patients mainly showed cortical blindness and unilateral vision loss; memory is generally reserved. Recent reports from neuroimaging show the occipital lobe may be involved in the processing of implicit memory (IM), especially the perception type of IM processing. In this study, we explored the explicit memory (EM) and IM damage in occipital lobe stroke patients. A total of 25 occipital strokes and 29 years of age, educational level equivalent healthy controls (HCs), evaluated by using immediate recall, delayed recall, recognition for EM tasks, picture identification, and category exemplar generation for IM tasks. There was no significant difference between occipital stroke patients and HCs in EM tasks and category exemplar generation task. In the picture identification task, occipital lobe stroke group score was poorer than HC group, the results were statistically significant, but in the pictures identify rate, occipital stroke patients and normal control group had no significant difference. The occipital stroke patients may have IM damage, primarily damage the perception type of IM priming effects, which was unrelated with their cortical blindness. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  15. Impairments in proverb interpretation following focal frontal lobe lesions☆

    Science.gov (United States)

    Murphy, Patrick; Shallice, Tim; Robinson, Gail; MacPherson, Sarah E.; Turner, Martha; Woollett, Katherine; Bozzali, Marco; Cipolotti, Lisa

    2013-01-01

    The proverb interpretation task (PIT) is often used in clinical settings to evaluate frontal “executive” dysfunction. However, only a relatively small number of studies have investigated the relationship between frontal lobe lesions and performance on the PIT. We compared 52 patients with unselected focal frontal lobe lesions with 52 closely matched healthy controls on a proverb interpretation task. Participants also completed a battery of neuropsychological tests, including a fluid intelligence task (Raven’s Advanced Progressive Matrices). Lesions were firstly analysed according to a standard left/right sub-division. Secondly, a finer-grained analysis compared the performance of patients with medial, left lateral and right lateral lesions with healthy controls. Thirdly, a contrast of specific frontal subgroups compared the performance of patients with medial lesions with patients with lateral frontal lesions. The results showed that patients with left frontal lesions were significantly impaired on the PIT, while in patients with right frontal lesions the impairments approached significance. Medial frontal patients were the only frontal subgroup impaired on the PIT, relative to healthy controls and lateral frontal patients. Interestingly, an error analysis indicated that a significantly higher number of concrete responses were found in the left lateral subgroup compared to healthy controls. We found no correlation between scores on the PIT and on the fluid intelligence task. Overall our results suggest that specific regions of the frontal lobes contribute to the performance on the PIT. PMID:23850600

  16. Impairments in proverb interpretation following focal frontal lobe lesions.

    Science.gov (United States)

    Murphy, Patrick; Shallice, Tim; Robinson, Gail; MacPherson, Sarah E; Turner, Martha; Woollett, Katherine; Bozzali, Marco; Cipolotti, Lisa

    2013-09-01

    The proverb interpretation task (PIT) is often used in clinical settings to evaluate frontal "executive" dysfunction. However, only a relatively small number of studies have investigated the relationship between frontal lobe lesions and performance on the PIT. We compared 52 patients with unselected focal frontal lobe lesions with 52 closely matched healthy controls on a proverb interpretation task. Participants also completed a battery of neuropsychological tests, including a fluid intelligence task (Raven's Advanced Progressive Matrices). Lesions were firstly analysed according to a standard left/right sub-division. Secondly, a finer-grained analysis compared the performance of patients with medial, left lateral and right lateral lesions with healthy controls. Thirdly, a contrast of specific frontal subgroups compared the performance of patients with medial lesions with patients with lateral frontal lesions. The results showed that patients with left frontal lesions were significantly impaired on the PIT, while in patients with right frontal lesions the impairments approached significance. Medial frontal patients were the only frontal subgroup impaired on the PIT, relative to healthy controls and lateral frontal patients. Interestingly, an error analysis indicated that a significantly higher number of concrete responses were found in the left lateral subgroup compared to healthy controls. We found no correlation between scores on the PIT and on the fluid intelligence task. Overall our results suggest that specific regions of the frontal lobes contribute to the performance on the PIT. © 2013 The Authors. Published by Elsevier Ltd. All rights reserved.

  17. Radiation effects in ice: New results

    International Nuclear Information System (INIS)

    Baragiola, R.A.; Fama, M.; Loeffler, M.J.; Raut, U.; Shi, J.

    2008-01-01

    Studies of radiation effects in ice are motivated by intrinsic interest and by applications in astronomy. Here we report on new and recent results on radiation effects induced by energetic ions in ice: amorphization of crystalline ice, compaction of microporous amorphous ice, electrostatic charging and dielectric breakdown and correlated structural/chemical changes in the irradiation of water-ammonia ices

  18. Caracterización de suelos bajo bosques de Nothofagus betuloides (Mirb Blume, en Tierra del Fuego, Chile Characterization of soils of Nothofagus betuloides (Mirb Blume forests, in Tierra del Fuego, Chile

    Directory of Open Access Journals (Sweden)

    VÍCTOR GERDING

    2002-12-01

    Full Text Available En tres sectores de la parte occidental de Tierra del Fuego (54º45'-54º15' S, 68º40'-70º10' O se caracterizó morfológica, física y químicamente los suelos bajo bosques de coigüe de Magallanes (Nothofagus betuloides (Mirb Blume y sus especies asociadas lenga (Nothofagus pumilio (P. et E. Krasser y canelo (Drimys winteri Forst.. Se describieron 85 perfiles de suelo y aproximadamente 250 observaciones con bastón pedológico. Los suelos bajo coigüe de Magallanes eran jóvenes, muy influidos por la actividad volcánica, topografía y clima. Se observó la presencia de los órdenes Spodosol e Iceptisol, principalmente. En general los suelos eran delgados a muy delgados (mayoritariamente entre 10 y 40 cm, con un alto volumen de esqueleto, textura franca, estructura masiva a granular, capacidad de agua aprovechable baja y drenaje externo e interno moderado a lento. Además, presentan una alta acidez (pH 4-5,5, una baja oferta nutricional y muy altos niveles de saturación de aluminio (promedio > 60 %. El mantillo (Oe/Oa presentó condiciones adecuadas para el desarrollo radicular. Existe comúnmente un horizonte blanco (frecuentemente 10 YR 5/1-2 inmediatamente debajo del mantillo, con textura franco limosa y estructura masiva, con arraigamiento muy bajo. Se plantea como hipótesis que este horizonte se originó por depósitos de cenizas volcánicas y procesos de podzolización. Se concluye que la fertilidad de estos suelos es baja debido a limitantes físicas (dificultades de arraigamiento y químicas (acidez, toxicidad de aluminio, baja oferta de basesSoils under coigüe de Magallanes (Nothofagus betuloides (Mirb Blume forests, located in the oriental part of Tierra del Fuego (54º45'-54º15' S, 68º40'-70º10' W, were characterized morphologically, physically and chemically. Associated tree species were lenga (Nothofagus pumilio (P. et E. Krasser and canelo (Drimys winterii Forst.. A total of 85 soil profiles and approximately 250 soil

  19. The making of salty ice

    International Nuclear Information System (INIS)

    Bove, L.E.

    2009-01-01

    Full text: It is widely accepted that ice, no matter what phase, is unable to incorporate large amount of salt into its structure. This conclusion is based on the observation that upon freezing of saltwater, ice expels the salt almost entirely into brine, a fact which can be exploited to desalinate seawater. Here we show, by neutron diffraction under high pressure, that this behaviour is not an intrinsic physico-chemical property of ice phases. We demonstrate that substantial am mounts of dissolved LiCl can be built homogeneously into the ice VII structure if it is produced by recrystallisation of its glassy state under pressure [1]. Such highly doped or alloyed ice VII has significantly different structural properties compared to pure ice VII, such as a 8% larger unit cell volume, 5 times larger displacement factors, an absence of a transition to an ordered ice VIII structure, plasticity, and most likely ionic conductivity. Our study suggests that there could be a whole new class of salty ices based on various kinds of solutes and high pressure ice forms. (author)

  20. Diffuse scattering in Ih ice

    International Nuclear Information System (INIS)

    Wehinger, Björn; Krisch, Michael; Bosak, Alexeï; Chernyshov, Dmitry; Bulat, Sergey; Ezhov, Victor

    2014-01-01

    Single crystals of ice Ih, extracted from the subglacial Lake Vostok accretion ice layer (3621 m depth) were investigated by means of diffuse x-ray scattering and inelastic x-ray scattering. The diffuse scattering was identified as mainly inelastic and rationalized in the frame of ab initio calculations for the ordered ice XI approximant. Together with Monte-Carlo modelling, our data allowed reconsidering previously available neutron diffuse scattering data of heavy ice as the sum of thermal diffuse scattering and static disorder contribution. (paper)

  1. Modelling the Antarctic Ice Sheet

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke; Holm, A.

    2015-01-01

    to sea level high stands during past interglacial periods. A number of AIS models have been developed and applied to try to understand the workings of the AIS and to form a robust basis for future projections of the AIS contribution to sea level change. The recent DCESS (Danish Center for Earth System......The Antarctic ice sheet is a major player in the Earth’s climate system and is by far the largest depository of fresh water on the planet. Ice stored in the Antarctic ice sheet (AIS) contains enough water to raise sea level by about 58 m, and ice loss from Antarctica contributed significantly...

  2. Improved ice loss estimate of the northwestern Greenland ice sheet

    NARCIS (Netherlands)

    Kjeldsen, K.K.; Khan, S.A.; van den Broeke, M.R.; van Angelen, J.H.

    2013-01-01

    We estimate ice volume change rates in the northwest Greenland drainage basin during 2003–2009 using Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data. Elevation changes are often reported to be largest near the frontal portion of outlet glaciers. To improve the volume change

  3. Eulerian method for ice crystal icing in turbofan engines

    NARCIS (Netherlands)

    Norde, Ellen

    2017-01-01

    The newer generations of high-bypass-ratio engines are susceptible to the ingestion of small ice crystals which may cause engine power loss or damage. The research presented in this thesis focusses on the development of a computational method for in-engine ice crystal accretion. The work has been

  4. Tropospheric characteristics over sea ice during N-ICE2015

    Science.gov (United States)

    Kayser, Markus; Maturilli, Marion; Graham, Robert; Hudson, Stephen; Cohen, Lana; Rinke, Annette; Kim, Joo-Hong; Park, Sang-Jong; Moon, Woosok; Granskog, Mats

    2017-04-01

    Over recent years, the Arctic Ocean region has shifted towards a younger and thinner sea-ice regime. The Norwegian young sea ICE (N-ICE2015) expedition was designed to investigate the atmosphere-snow-ice-ocean interactions in this new ice regime north of Svalbard. Here we analyze upper-air measurements made by radiosondes launched twice daily together with surface meteorology observations during N-ICE2015 from January to June 2015. We study the multiple cyclonic events observed during N-ICE2015 with respect to changes in the vertical thermodynamic structure, sudden increases in moisture content and temperature, temperature inversions and boundary layer dynamics. The influence of synoptic cyclones is strongest under polar night conditions, when radiative cooling is most effective and the moisture content is low. We find that transitions between the radiatively clear and opaque state are the largest drivers of changes to temperature inversion and stability characteristics in the boundary layer during winter. In spring radiative fluxes warm the surface leading to lifted temperature inversions and a statically unstable boundary layer. The unique N-ICE2015 dataset is used for case studies investigating changes in the vertical structure of the atmosphere under varying synoptic conditions. The goal is to deepen our understanding of synoptic interactions within the Arctic climate system, to improve model performance, as well as to identify gaps in instrumentation, which precludes further investigations.

  5. Arctic Sea Ice Freeboard and Thickness

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides measurements of sea ice freeboard and sea ice thickness for the Arctic region. The data were derived from measurements made by from the Ice,...

  6. Pathogenic and enzyme activities of the entomopathogenic fungus Tolypocladium cylindrosporum (Ascomycota: Hypocreales from Tierra del Fuego, Argentina

    Directory of Open Access Journals (Sweden)

    Ana C Scorsetti

    2012-06-01

    Full Text Available Tolypocladium cylindrosporum is an entomopathogenic fungi that has been studied as a biological control agent against insects of several orders. The fungus has been isolated from the soil as well as from insects of the orders Coleoptera, Lepidoptera, Diptera and Hymenoptera. In this study, we analyzed the ability of a strain of T. cylindrosporum, isolated from soil samples taken in Tierra del Fuego, Argentina, to produce hydrolytic enzymes, and to study the relationship of those activities to the fungus pathogenicity against pest aphids. We have made the traditional and molecular characterization of this strain of T. cylindrosporum. The expression of hydrolase activity in the fungal strain was estimated at three incubation temperatures (4ºC, 12ºC and 24ºC, on different agar media supplemented with the following specific substrates: chitin azure, Tween ® 20, casein, and urea for chitinase, lipase, protease, and urease activity, respectively. The hydrolytic-enzyme activity was estimated qualitatively according to the presence of a halo of clarification through hydrolase action, besides was expressed semi-quantitatively as the ratio between the hydrolytic-halo and colony diameters. The pathogenicity of the fungus was tested on adults of the aphid Rhopalosiphum padi at three temperatures of incubation (4ºC, 12ºC and 24ºC. The suspension was adjusted to a concentration of 1x10 7 conidia/ml. In pathogenicity assays at seven days post-inoculation, the fungus caused the mortality of adults of Ropalosiphum padi at different temperatures also showed a broad ability to grow on several agar-culture media, supplemented with different carbon sources at the three incubation temperatures tested. Although, the growth was greater with higher incubation temperatures (with maximum levels at 24°C, the fungus reached similar colony diameters after 15 days of incubation on the medium supplemented with Tween® 20 at the lower two incubation temperatures of 4

  7. Comportamiento de comunidades de lombrices de tierra en dos sistemas ganaderos Behavior of earthworm communities in two livestock production systems

    Directory of Open Access Journals (Sweden)

    Saray Sánchez

    2011-09-01

    Full Text Available Con el objetivo de evaluar el comportamiento de comunidades de lombrices de tierra en dos sistemas ganaderos (pastizal de gramíneas y sistema silvopastoril, los cuales se manejaron para la ceba de animales vacunos y la producción de semillas, se realizó una investigación en la Estación Experimental de Pastos y Forrajes «Indio Hatuey», Matanzas. Para el estudio de las comunidades de lombrices se hicieron seis colectas. En cada una de las áreas descritas se tomaron 40 muestras de suelo, según la Metodología del Programa de Investigación Internacional «Biología y Fertilidad del Suelo Tropical». Se encontraron 297 y 740 organismos en el pastizal de gramíneas y en el sistema silvopastoril, respectivamente. La especie Onychochaeta elegans mostró una mayor abundancia proporcional en el pastizal de gramíneas; mientras que en el sistema silvopastoril se encontraron tres especies, de ellas dos típicas de zonas boscosas: Polypheretima elongata y Onychochaeta windlei; la primera tuvo un mayor valor, con diferencias significativas respecto a las especies halladas del género Onychochaeta. Se concluye que la presencia de árboles en pastizales de gramíneas contribuye a estimular los organismos del suelo, en especial las lombrices de tierra, las que desempeñan un papel importante al mejorar no solo los indicadores físicos y químicos de este, sino también como estimuladoras de otros organismos.In order to evaluate the behavior of earthworm communities in two livestock production systems (grassland and silvopastoral system, which were managed for cattle fattening and seed production, a study was conducted at the Experimental Station of Pastures and Forages «Indio Hatuey», Matanzas. For the study of the earthworm communities six collections were made. In each of the described areas 40 soil samples were taken, according to the Methodology of the International Research Program «Tropical Soil Biology and Fertility». In the grassland and

  8. Climate Impacts of Ice Nucleation

    Science.gov (United States)

    Gettelman, Andrew; Liu, Xiaohong; Barahona, Donifan; Lohmann, Ulrike; Chen, Celia

    2012-01-01

    Several different ice nucleation parameterizations in two different General Circulation Models (GCMs) are used to understand the effects of ice nucleation on the mean climate state, and the Aerosol Indirect Effects (AIE) of cirrus clouds on climate. Simulations have a range of ice microphysical states that are consistent with the spread of observations, but many simulations have higher present-day ice crystal number concentrations than in-situ observations. These different states result from different parameterizations of ice cloud nucleation processes, and feature different balances of homogeneous and heterogeneous nucleation. Black carbon aerosols have a small (0.06 Wm(exp-2) and not statistically significant AIE when included as ice nuclei, for nucleation efficiencies within the range of laboratory measurements. Indirect effects of anthropogenic aerosols on cirrus clouds occur as a consequence of increasing anthropogenic sulfur emissions with different mechanisms important in different models. In one model this is due to increases in homogeneous nucleation fraction, and in the other due to increases in heterogeneous nucleation with coated dust. The magnitude of the effect is the same however. The resulting ice AIE does not seem strongly dependent on the balance between homogeneous and heterogeneous ice nucleation. Regional effects can reach several Wm2. Indirect effects are slightly larger for those states with less homogeneous nucleation and lower ice number concentration in the base state. The total ice AIE is estimated at 0.27 +/- 0.10 Wm(exp-2) (1 sigma uncertainty). This represents a 20% offset of the simulated total shortwave AIE for ice and liquid clouds of 1.6 Wm(sup-2).

  9. Linking invasive exotic vertebrates and their ecosystem impacts in Tierra del Fuego to test theory and determine action

    Science.gov (United States)

    Valenzuela, Alejandro E. J.; Anderson, Christopher B.; Fasola, Laura; Cabello, José L.

    2014-01-01

    Understanding processes and impacts of biological invasions is fundamental for ecology and management. Recent reviews summarized the mechanisms by which invasive species alter entire ecosystems, but quantitative assessments of these mechanisms are lacking for actual assemblages to determine their relative importance, frequency and patterns. We updated information on introduced vertebrates in the Tierra del Fuego Archipelago (TDF) via an exhaustive literature review and new data to evaluate ecosystem impact mechanisms and provide management recommendations. To date, 24 exotic vertebrates have naturalized in TDF, outnumbering natives nearly 2:1, with the North American beaver (Castor canadensis) and muskrat (Ondatra zibethica) being the most widely distributed species and also impacting the ecosystem through the greatest number of mechanisms. Introduced vertebrates occupied most parts of the archipelago with human-inhabited islands having greater taxa richness. All exotics potentially altered ecosystems by one or more mechanisms: 100% food webs, 92% invasional meltdown, 42% habitat modification, 38% disease or parasite transmission, 21% soil property and disturbance regime changes. Impact to habitat structure was the main clustering criterion for this assemblage. Within the species that physically alter habitats, we found two sub-groups: 1) large herbivores and 2) "others" including beavers and muskrats. Species that did not alter habitat were divided further into those with predatory trophic effects (carnivorous mammals and trout, sub-group 4) and the rest with assorted impacts (sub-group 3). By establishing high quality information on archipelago-wide assemblage, distribution, impacts and mechanisms for exotic vertebrates, we recommend, based on ecological criteria, prioritizing the management of sub-group 2. A secondary priority might be given to the carnivores in sub-group 4, while species in sub-groups 1 and 3 are less urgent. As the first systematic survey of

  10. Rayleigh waves from correlation of seismic noise in Great Island of Tierra del Fuego, Argentina: Constraints on upper crustal structure

    Directory of Open Access Journals (Sweden)

    Carolina Buffoni

    2018-01-01

    Full Text Available In this study, the ambient seismic noise cross-correlation technique is applied to estimate the upper structure of the crust beneath Great Island of Tierra del Fuego (TdF, Argentina, by the analysis of short-period Rayleigh wave group velocities. The island, situated in the southernmost South America, is a key area of investigation among the interaction between the South American and Scotia plates and is considered as a very seismically active one. Through cross-correlating the vertical components of ambient seismic noise registered at four broadband stations in TdF, we were able to extract Rayleigh waves which were used to estimate group velocities in the period band of 2.5–16 s using a time-frequency analysis. Although ambient noise sources are distributed inhomogeneously, robust empirical Green's functions could be recovered from the cross-correlation of 12 months of ambient noise. The observed group velocities were inverted considering a non-linear iterative damped least-squares inversion procedure and several 1-D shear wave velocity models of the upper crust were obtained. According to the inversion results, the S-wave velocity ranges between 1.75 and 3.7 km/s in the first 10 km of crust, depending on the pair of stations considered. These results are in agreement to the major known surface and sub-surface geological and tectonic features known in the area. This study represents the first ambient seismic noise analysis in TdF in order to constraint the upper crust beneath this region. It can also be considered as a successful feasibility study for future analyses with a denser station deployment for a more detailed imaging of structure.

  11. Perfil epidemiológico del accidente ofídico en las tierras bajas de Guatemala

    Directory of Open Access Journals (Sweden)

    Dennis Guerra-Centeno

    2017-03-01

    Full Text Available Se describe el perfil epidemiológico del accidente ofídico en las tierras bajas de Guatemala a partir del análisis de 305 expedientes de casos atendidos en los hospitales regionales de Escuintla y San Benito, Petén, entre 2008 y 2013. De los 305 casos, 169 correspondieron al Hospital Regional de Escuintla y 136 al Hospital Regional de San Benito Petén. Los casos del Hospital Regional de Escuintla correspondieron a pacientes provenientes de los departamentos de Escuintla, Santa Rosa, Chimaltenango, Retalhuleu, Suchitepéquez, Sacatepéquez, Sololá y Guatemala. Los casos del Hospital Regional de San Benito Petén correspondieron a pacientes provenientes del área centro y norte de Petén, y algunos referidos del área sur. La edad media de la víctima fue 25.2 años. La enfermedad afectó más a hombres (61.3% que a mujeres (38.7%. La mayoría de los afectados (28.3% eran agricultores. Las especies de serpiente que se consignaron en los expedientes con mayor frecuencia fueron Bothrops asper (serpiente barba amarilla en la región norte y Crotalus simus (serpiente cascabel en la región sur. La mayoría de las mordeduras ocurrieron en los miembros inferiores. Los eventos de mordedura ocurrieron durante el día y durante la noche en proporciones similares. El tiempo medio que tarda la víctima en llegar al hospital fue de 5.6 horas. Se describen también otros aspectos epidemiológicos y se discuten las implicaciones ecológicas y sociales de los datos generados.

  12. Construcción e impacto sobre el ambiente: el caso de la tierra y otros materiales

    Directory of Open Access Journals (Sweden)

    Vázquez Espí, Mariano

    2001-02-01

    Full Text Available The assessment of the impact on the environment of the diverse human activities becomes more unavoidable as the signs of the ecological damage become more evident. Here, the relative merit of several formulations for the physical cost of building (embodied energy, exergy cost and matter cost of materials is analysed; it is also analysed the structure of the aggregate physical cost, including the relative evaluation of its more meaningful items. As a way of concrete examples, the energy and matter embodied into different building functions is evaluated depending on the material used (earth, steel, concrete, brick. Lastly, some conclusions about the attributes of a future, "sustainable" building are taken out.Conforme los indicios del deterioro ecológico se hacen más evidentes, la evaluación del impacto sobre el ambiente de las distintas actividades humanas se vuelve más insoslayable. Aquí se analiza el relativo mérito de distintas formulaciones del coste físico de la construcción: energía incorporada, coste exergético y coste material; también la estructura del coste físico agregado, incluyendo la valoración relativa de sus términos más significativos. Como ejemplos concretos, se evalúa la energía y la materia incorporada por distintas funciones constructivas según el material empleado (tierra, acero, ladrillo, hormigón. Finalmente, se extraen algunas conclusiones acerca de las características de una futura construcción "sostenible ".

  13. Intrinsic controls on the range of volumes, morphologies, and dimensions of submarine lobes

    Science.gov (United States)

    Prélat, A.; Covault, J. A.; Hodgson, D. M.; Fildani, A.; Flint, S. S.

    2010-12-01

    Submarine lobe dimensions from six different systems are compared: 1) the exhumed Permian Fan 3 lobe complex of the Tanqua Karoo, South Africa; 2) the modern Amazon fan channel-mouth lobe complex, offshore Brazil; 3) a portion of the modern distal Zaïre fan, offshore Angola/Congo; 4) a Pleistocene fan of the Kutai basin, subsurface offshore Indonesia; 5) the modern Golo system, offshore east Corsica, France; and 6) a shallow subsurface lobe complex , offshore Nigeria. These six systems have significantly different source-to-sink configurations (shelf dimension and slope topography), sediment supply characteristics (available grain size range and supply rate), tectonic settings, (palaeo) latitude, and delivery systems. Despite these differences, lobe deposits share similar geometric and dimensional characteristics. Lobes are grouped into two distinct populations of geometries that can be related to basin floor topography. The first population corresponds to areally extensive but thin lobes (average width 14 km × length 35 km × thickness 12 m) that were deposited onto low relief basin floor areas. Examples of such systems include the Tanqua Karoo, the Amazon, and the Zaïre systems. The second population corresponds to areally smaller but thicker lobes (average width 5 km × length 8 km × thickness 30 m) that were deposited into settings with higher amplitude of relief, like in the Corsican trough, the Kutai basin, and offshore Nigeria. The two populations of lobe types, however, share similar volumes (a narrow range around 1 or 2 km 3), which suggests that there is a control to the total volume of sediment that individual lobes can reach before they shift to a new locus of deposition. This indicates that the extrinsic processes control the number of lobes deposited per unit time rather than their dimensions. Two alternative hypotheses are presented to explain the similarities in lobe volumes calculated from the six very different systems. The first states that

  14. Abnormal activation of the occipital lobes during emotion picture processing in major depressive disorder patients

    Science.gov (United States)

    Li, Jianying; Xu, Cheng; Cao, Xiaohua; Gao, Qiang; Wang, Yan; Wang, Yanfang; Peng, Juyi; Zhang, Kerang

    2013-01-01

    A large number of studies have demonstrated that depression patients have cognitive dysfunction. With recently developed brain functional imaging, studies have focused on changes in brain function to investigate cognitive changes. However, there is still controversy regarding abnormalities in brain functions or correlation between cognitive impairment and brain function changes. Thus, it is important to design an emotion-related task for research into brain function changes. We selected positive, neutral, and negative pictures from the International Affective Picture System. Patients with major depressive disorder were asked to judge emotion pictures. In addition, functional MRI was performed to synchronously record behavior data and imaging data. Results showed that the total correct rate for recognizing pictures was lower in patients compared with normal controls. Moreover, the consistency for recognizing pictures for depressed patients was worse than normal controls, and they frequently recognized positive pictures as negative pictures. The consistency for recognizing pictures was negatively correlated with the Hamilton Depression Rating Scale. Functional MRI suggested that the activation of some areas in the frontal lobe, temporal lobe, parietal lobe, limbic lobe, and cerebellum was enhanced, but that the activation of some areas in the frontal lobe, parietal lobe and occipital lobe was weakened while the patients were watching positive and neutral pictures compared with normal controls. The activation of some areas in the frontal lobe, temporal lobe, parietal lobe, and limbic lobe was enhanced, but the activation of some areas in the occipital lobe were weakened while the patients were watching the negative pictures compared with normal controls. These findings indicate that patients with major depressive disorder have negative cognitive disorder and extensive brain dysfunction. Thus, reduced activation of the occipital lobe may be an initiating factor for

  15. Ice hockey injuries.

    Science.gov (United States)

    Benson, Brian W; Meeuwisse, Willem H

    2005-01-01

    This article reviews the distribution and determinants of injuries reported in the pediatric ice hockey literature, and suggests potential injury prevention strategies and directions for further research. Thirteen electronic databases, the ISI Web of Science, and 'grey literature' databases were searched using a combination of Medical Subject Headings and text words to identify potentially relevant articles. The bibliographies of selected studies were searched to identify additional articles. Studies were selected for review based on predetermined inclusion and exclusion criteria. A comparison between studies on this topic area was difficult due to the variability in research designs, definition of injury, study populations, and measurements used to assess injury. The majority of injuries were sustained during games compared with practices. The two most commonly reported injuries were sprains/strains and contusions. Players competing at the Minor hockey, High School, and Junior levels of competition sustained most of their injuries to the upper extremity, head, and lower extremity, respectively. The primary mechanism of injury was body checking, followed by stick and puck contact. The frequency of catastrophic eye injuries has been significantly reduced with the world-wide mandation of full facial protection for all Minor hockey players. Specific hockey-related injury risk factors are poorly delineated and rarely studied among pediatric ice hockey players leaving large gaps in the knowledge of appropriate prevention strategies. Risk management strategies should be focused at avoiding unnecessary foreseeable risk, and controlling the risks inherent to the sport. Suggestions for injury prevention and future research are discussed.

  16. The physics of ice cream

    Science.gov (United States)

    Clarke, Chris

    2003-05-01

    Almost everybody likes ice cream, so it can provide an excellent vehicle for discussing and demonstrating a variety of physical phenomena, such as Newton's law of cooling, Boyle's law and the relationship between microstructure and macroscopic properties (e.g. Young's modulus). Furthermore, a demonstration of freezing point depression can be used to make ice cream in the classroom!

  17. Snow, ice and solar radiation

    NARCIS (Netherlands)

    Kuipers Munneke, P.

    2009-01-01

    The snow-covered ice sheets of Antarctica and Greenland reflect most of the incoming solar radiation. The reflectivity, commonly called the albedo, of snow on these ice sheets has been observed to vary in space and time. In this thesis, temporal and spatial changes in snow albedo is found to depend

  18. Ice as a Construction Material

    Science.gov (United States)

    Zuppero, Anthony; Lewis, Joseph

    1998-01-01

    The use of ice as a construction material is discussed. A model of an ice tire torus space ship, which slowly spins to produce artificial gravity is proposed. The size of the ship, needed to support a given number of people and the required envelope mass is presented.

  19. Proton MR spectroscopy in patients with acute temporal lobe seizures.

    Science.gov (United States)

    Castillo, M; Smith, J K; Kwock, L

    2001-01-01

    Decreases in N-acetyl aspartate (NAA) as seen by proton MR spectroscopy are found in hippocampal sclerosis, and elevated levels of lipids/lactate have been observed after electroconvulsive therapy. Our purpose was to determine whether increased levels of lipids/lactate are found in patients with acute seizures of hippocampal origin. Seventeen patients with known temporal lobe epilepsy underwent proton MR spectroscopy of the mesial temporal lobes within 24 hours of their last seizure. Four of them were restudied when they were seizure-free. Five healthy individuals were used as control subjects. All MR spectroscopy studies were obtained using a single-voxel technique with TEs of 135 and 270. The relationship between the presence of lipids/lactate and seizures was tested using Fisher's exact test. Mean and standard deviations for NAA/creatine (Cr) were obtained in the hippocampi in patients with seizures on initial and follow-up studies and these values were compared with those in the control subjects. Seizure lateralization was obtained in 15 patients. Of the 17 seizure locations that involved hippocampi, 16 showed lipids/lactate by proton MR spectroscopy. Of the 13 hippocampi not directly affected by seizures, 10 showed no lipids/lactate and three showed lipids/lactate. The relationship between lipids/lactate and seizure location was confirmed. A comparison of NAA/Cr ratios for the involved hippocampi with those in control subjects showed significant differences on initial MR spectroscopy; however, no significant difference was found between acute and follow-up NAA/Cr ratios in hippocampi affected by seizures. Lipids/lactate were present in the hippocampi of patients with acute seizures and decreased when the patients were seizure-free. Thus, lipids/lactate may be a sensitive marker for acute temporal lobe seizures.

  20. Emotional reactions in patients after frontal lobe stroke

    Directory of Open Access Journals (Sweden)

    Stojanović Zlatan

    2015-01-01

    Full Text Available Background/Aim. Emotional reactions have been documented after tumor lesions and the other damages of the brain. The aim of this paper was to examine the correlation between frontal lobe lesions and emotional reactions in patients with stroke. Methods. The research included 118 patients after stroke. Lesion localization was defined on computed axial tomography records, whereas the area and perimeter of lesion were measured by AutoCAD 2004 software. Examinations by means of the Hamilton Rating Scale for Anxiety and Depression (HRSA and HRSD were carried out 11-40 days after stroke. Statistic data were processed by simple linear/nonlinear regression, Cox's and the generalized linear model. Results. A higher frequency of emotional reactions, i.e. anxiety, was determined in women after stroke (p = 0.024. A negative correlation between the lesion size and the intensity of anxiety manifestations was determined (Spearman’s r = -0.297; p = 0.001. Anxiety was more frequent in patients with frontal lobe lesions in the dominant hemisphere (interaction: frontal lesion * hand dominant hemisphere, p = 0.017. Also, HRSD score values showed the tendency for lesser decline in case of greater frontal lobe lesions in relation to lesions of other regions of prosencephalon (interaction: frontal lesion * lesion area, p = 0.001. Conclusion. The results of this study indicate the correlation between evolutionary younger structures of the central nervous system and emotional reactions of man. Therefore, it is necessary to undertake proper early psychopharmacotherapy in the vulnerable group of patients.

  1. Diagnosis of temporal lobe epilepsy by positron emission tomography

    International Nuclear Information System (INIS)

    Shimizu, Hiroyuki; Ishijima, Buichi; Iio, Masaaki.

    1985-01-01

    Positron emission tomography(PET) was performed in 18 temporal lobe epileptics. About 20 mCi of 11 C-glucose was perorally administered to the patients and 30 minutes later scanning was started when the transport of 11 C-glucose from blood to the brain tissue reached equilibrium. At the level of 25mm above orbitomeatal line, the slice image of the temporal lobe shows a relatively high metabolic oval ring involving the amygdala, hippocapal formation and the hippocampal gyrus medially and the T 1 , T 2 and T 3 neocortices laterally in normal subjects. The epileptic focus, when detected on PET images, was observed as a defect in this oval ring. In 15(83.3%) out of 18 cases, the location of epileptic focus was confirmed as a low metabolic defect. This diagnosis rate was higher than that of other focal epilepsy by PET study. The locations of foci were devided into three types: mesial (5 cases), lateral (4 cases) and combined (6 cases). The seizure symptoms of the patients were analyzed in terms of the correspondence to the focus types. The results showed that automatism and pseudoabsence had a close relation to the mesial and combined types and psychical, vertiginous or visual seizures correlated to the combined and lateral types. Visceral or motor seizures were induced equally by any focus types. These facts suggested that automatism and pseudoabsence were correlated with the mesial organs such as the amygdala and hippocampus and psychical, vertiginous or visual seizures had origin in lateral neocortices. Visceral or motor seizures were supposed to be the results of the spread from the temporal focus to the adjacent structures. It was concluded that PET was very useful in localization diagnosis of temporal lobe epilepsy. In surgical treatment of epilepsy, in which the knowledge of the exact extent of epileptic foci is strongly demanded, PET study will offer invaluable data to the strategy of operation and foreseeing its prognosis. (author)

  2. Temporal lobe epilepsy: analysis of patients with dual pathology.

    Science.gov (United States)

    Salanova, V; Markand, O; Worth, R

    2004-02-01

    To determine the frequency and types of dual pathology in patients with temporal lobe epilepsy (TLE) and to analyze the clinical manifestations and surgical outcome. A total of 240 patients with TLE underwent temporal resections following a comprehensive pre-surgical evaluation. Thirty-seven (15.4%) of these had hippocampal sclerosis (HS) or temporal lobe gliosis in association with another lesion (dual pathology). Eighteen of 37 patients with dual pathology had heterotopia of the temporal lobe, nine had cortical dysplasia, four had cavernous angiomas or arteriovenous malformations, one had a dysembryoplastic neuroepithelial tumor, one had a contusion and four patients had cerebral infarctions in childhood. 68.5% had abnormal head magnetic resonance imagings, 91.3% had abnormal positron emission tomography scans, and 96% had abnormal ictal SPECT. The intracarotid amobarbital procedure (IAP) showed impaired memory of the epileptogenic side in 72% of the patients. Twenty patients had left and 17 had right-sided en bloc temporal resections, including the lesion and mesial temporal structures. Twenty-six (70.2%) became seizure-free, eight (21.6%) had rare seizures, two (5.4%) had worthwhile seizure reduction and one (2.7%) had no improvement (range of follow-up 1-16 years, mean = 7.4 years). 15.4% had dual pathology. The dual pathology was almost exclusively seen in patients whose lesions were congenital, or occurred early in life, suggesting that the hippocampus is more vulnerable and more readily develops HS in early childhood. Resections, including the lateral and mesial temporal structures led to a favorable outcome with no mortality and little morbidity.

  3. Differences in the neural correlates of frontal lobe tests.

    Science.gov (United States)

    Matsuoka, Teruyuki; Kato, Yuka; Imai, Ayu; Fujimoto, Hiroshi; Shibata, Keisuke; Nakamura, Kaeko; Yamada, Kei; Narumoto, Jin

    2018-01-01

    The Executive Interview (EXIT25), the executive clock-drawing task (CLOX1), and the Frontal Assessment Battery (FAB) are used to assess executive function at the bedside. These tests assess distinct psychometric properties. The aim of this study was to examine differences in the neural correlates of the EXIT25, CLOX1, and FAB based on magnetic resonance imaging. Fifty-eight subjects (30 with Alzheimer's disease, 10 with mild cognitive impairment, and 18 healthy controls) participated in this study. Multiple regression analyses were performed to examine the brain regions correlated with the EXIT25, CLOX1, and FAB scores. Age, gender, and years of education were included as covariates. Statistical thresholds were set to uncorrected P-values of 0.001 at the voxel level and 0.05 at the cluster level. The EXIT25 score correlated inversely with the regional grey matter volume in the left lateral frontal lobe (Brodmann areas 6, 9, 44, and 45). The CLOX1 score correlated positively with the regional grey matter volume in the right orbitofrontal cortex (Brodmann area 11) and the left supramarginal gyrus (Brodmann area 40). The FAB score correlated positively with the regional grey matter volume in the right precentral gyrus (Brodmann area 6). The left lateral frontal lobe (Brodmann area 9) and the right lateral frontal lobe (Brodmann area 46) were identified as common brain regions that showed association with EXIT25, CLOX1, and FAB based only a voxel-level threshold. The results of this study suggest that the EXIT25, CLOX1, and FAB may be associated with the distinct neural correlates of the frontal cortex. © 2018 Japanese Psychogeriatric Society.

  4. La formación del mercado de tierras durante la expansión de la frontera bonaerense. Chascomús y Junín, 1860-1890

    Directory of Open Access Journals (Sweden)

    Guillermo Banzato

    2009-04-01

    Full Text Available En este trabajo nos proponemos analizar la formación del mercado de tierras durante la expansión de la frontera de la provincia de Buenos Aires entre 1860 y 1890, a partir de un enfoque local comparado, enfocando la investigación en dos partidos: Chascomús y Junín. Postulamos que la constitución del mercado de tierras en la campaña bonaerense fue un proceso gradual, que se inició apenas comenzaron a poblarse las tierras defendidas por los fuertes de la frontera interior y se establecían ciertas garantías de seguridad para la propiedad privada

  5. Are the dimensions of submarine lobe systems independent of allogenic factors?

    Science.gov (United States)

    Prélat, A.; Covault, J. A.; Hodgson, D. M.; Fildani, A.; Flint, S. S.

    2010-05-01

    Submarine lobe dimensions from six different systems are compared: 1) the exhumed Permian Fan 3 lobe complex of the Tanqua Karoo, South Africa; 2) the modern Amazon fan channel-mouth lobe complex, offshore Brazil; 3) a portion of the modern distal Zaïre fan, offshore Angola / Congo; 4) a Pleistocene fan of the Kutai Basin, subsurface offshore Indonesia; 5) the modern Golo system, offshore east Corsica, France; and 6) a lobe complex deposited in the shallow subsurface, offshore Nigeria. These six systems have significantly different source-to-sink configurations (shelf dimension and slope topography), sediment supply characteristics (calibre and rate), tectonic settings, (palaeo) latitude, and delivery systems. Despite these differences, the lobe deposits share similar geometric and dimensional characteristics. Lobes are grouped into two distinct populations of geometries that can be related to basin-floor topography. The first population corresponds to areally extensive but thin lobes (average width 14 km × length 35 km × thickness 12 m) that were deposited onto low relief basin floor areas, like the Tanqua Karoo, the Amazon and the Zaïre systems. The second population corresponds to areally smaller but thicker lobes (average width 5 km × length 8 km × thickness 30 m) that were deposited into settings with higher amplitude of relief, like in the Corsican trough, the Kutai basin, and offshore Nigeria. Basin floor topography confining the lobes can be very subtle, and only occur on one side of the system. The two populations of lobe types, however, share similar volumes, in the order of 1 or 2 km3. The largest lobes are observed in the Zaïre fan, where the average lobe volume reaches 3.3 km3 and the smallest lobes are observed in the Corsican trough where the average lobe volume is 0.4 km3. This variation in lobe volume is minor when compared to the variation observed in present-day up-dip drainage systems, which provide sediment to the deep-water depositional

  6. La mecánica de fluidos y la teoría de la figura de la Tierra entre Newton y Clairaut (1687-1743)

    OpenAIRE

    Lafuente, Antonio

    1983-01-01

    El objeto de este artículo es analizar la literatura publicada sobre el tema de la figura de la Tierra entre 1687 y 1743. La primera fecha coincide con la publicación de los Philosophiae Naturalis Principia Mathematica. El estudio de Newton demostraba la insuficiencia de recursos de la ciencia experimental y el abismo existente entre la precisión que podían asegurar los métodos de la astronomía práctica y las nuevas exigencias planteadas por su mecánica celeste. La segunda fech...

  7. ENTRE LA COSTA DE COBIJA Y TIERRAS ALTAS: EL TRÁFICO ARRIERO A INICIOS DE LA REPÚBLICA BOLIVIANA

    OpenAIRE

    Letelier Cosmelli, Javiera

    2016-01-01

    Desde la configuración del Puerto de Cobija hasta la guerra del Pacífico, tanto indígenas como bolivianos y extranjeros establecieron relaciones en el marco de un contexto cambiante y complejo tanto a nivel nacional como internacional en donde se introduce la economía capitalista industrial. Es en ese marco que los arrieros y la movilidad entre costa y tierras altas se constituyeron en piezas claves para dar vida a Cobija y resto de Atacama. A partir de este escenario realizamos una revisión ...

  8. Impacto social del arrendamiento de tierras para generar energía eléctrica en La Venta, Juchitán de Zaragoza, Oaxaca.

    OpenAIRE

    Racilla Manuel, Sarita

    2013-01-01

    La investigación analiza lo que es el impacto social del arrendamiento de tierras y los cambios producidos por la instalación de parques eólicos, como caso de estudio del Ejido de La Venta, Juchitán de Zaragoza, Oaxaca. La tesis se realizó con una metodología mixta;(cuantitativa-cualitativa), para analizar el fenómeno antes descrito; está comprendida en cuatro capítulos. El primer capítulo plantea la estructura general de la investigación. El segundo, aborda el marco teórico y distintas visio...

  9. The profile of the imprisoned minors in detention centres for offenders and the professionals who treat them: a descriptive study in the Tierras de Oria institution

    Directory of Open Access Journals (Sweden)

    Tomás Sola Martínez

    2009-05-01

    Full Text Available Although juvenile delinquency is a present matter in media since many years ago, the profile that defines both imprisoned minors in detention centres and proffesionals who treat them is still unknown for most of our society. This article aims for these profiles to be shown by means of a descriptive study carried out in the “Tierras de Oria” institution about the age, gender and education of both their inmates and the proffesionals who intervene in their re-education and guarantee their social and labour rehabilitation when they join our society.

  10. Patrones de distribución de especies arbóreas de dosel y sotobosque a escala local en bosques de tierra firme, Amazonia colombiana

    OpenAIRE

    Juan Sebastian Barreto-Silva; Dairon Cárdenas López; Álvaro Javier Duque Montoya

    2014-01-01

    El efecto de la variación ambiental en la estructura de las comunidades arbóreas en bosques tropicales, aún se debate. En paisajes como los bosques de tierra firme, donde el gradiente ambiental disminuye, el efecto de los suelos sobre los patrones de distribución de especies es mínimo. En contraste, un mayor efecto de la variación edáfica y topográfica sobre la composición florística, se ha reportado en estudios con diferentes tipos de plantas en bosques tropicales. Este estudio se realizó en...

  11. Modelación de sistemas de puesta a tierra para evaluación de sobretensiones transitorias; Modelling large grounding systems to evaluate transient voltages

    Directory of Open Access Journals (Sweden)

    Yandi Anibal Gallego Landera

    2015-04-01

    Full Text Available En plantas generadoras y en subestaciones se requieren sistemas de puesta a tierra (SPT espaciosos, con configuraciones complejas como parte del sistema de protección contra rayos. Las corrientes provocadas por una descarga atmosférica pueden causar altas tensiones en los cables de señales ubicados cerca de los SPT. Estas tensiones transitorias pueden causar falsas señales, las cuales provocan un mal funcionamiento de la instrumentación electrónica. Determinar medidas de protección contra rayos requiere del conocimiento de la máxima elevación de la tensión entre el SPT y la tierra remota. El presente trabajo propone una metodología para analizar el comportamiento transitorio de redes de tierra. La técnica se basa en considerar los diferentes segmentos de la malla de tierra como elementos de líneas de transmisión. Para desarrollar esta metodología se utilizó el software MATLAB-Simulink. Los resultados se validan por comparación con modelos basados en la teoría del campo electromagnético publicados en la literatura. In generating plants and substations spacious grounding systems with complex configuration as part of the protection system against lighting, are required. The current caused by an atmospheric discharge can cause high voltages in the signal cables located near the grounding systems. These transient voltages may be the reason for the occurrence of false signals, which can cause malfunctioning and of electronic instruments. The knowledge of maximum elevation of voltage between the grounding systems and the remote ground is required to determine protection against lightning. This paper proposes a methodology to analyze the transient behavior of grounding grid. The technique is based on considering the different segments of the ground grid as elements of transmission lines. For modeling the grounding systems behavior in its transient state faster, the MATLAB-Simulink software was used. The results were validated by

  12. Ice sheet hydrology from observations

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ-, Stockholm (Sweden)

    2010-11-15

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  13. Ice sheet hydrology from observations

    International Nuclear Information System (INIS)

    Jansson, Peter

    2010-11-01

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  14. Anton's Syndrome due to Bilateral Ischemic Occipital Lobe Strokes.

    Science.gov (United States)

    Zukić, Sanela; Sinanović, Osman; Zonić, Lejla; Hodžić, Renata; Mujagić, Svjetlana; Smajlović, Edina

    2014-01-01

    We present a case of a patient with Anton's syndrome (i.e., visual anosognosia with confabulations), who developed bilateral occipital lobe infarct. Bilateral occipital brain damage results in blindness, and patients start to confabulate to fill in the missing sensory input. In addition, the patient occasionally becomes agitated and talks to himself, which indicates that, besides Anton's syndrome, he might have had Charles Bonnet syndrome, characterized by both visual loss and hallucinations. Anton syndrome, is not so frequent condition and is most commonly caused by ischemic stroke. In this particular case, the patient had successive bilateral occipital ischemia as a result of massive stenoses of head and neck arteries.

  15. Déjà Experiences in Temporal Lobe Epilepsy

    OpenAIRE

    Illman, Nathan A.; Butler, Chris R.; Souchay, Celine; Moulin, Chris J. A.

    2012-01-01

    Historically, déjà vu has been linked to seizure activity in temporal lobe epilepsy, and clinical reports suggest that many patients experience the phenomenon as a manifestation of simple partial seizures. We review studies on déjà vu in epilepsy with reference to recent advances in the understanding of déjà vu from a cognitive and neuropsychological standpoint. We propose a decoupled familiarity hypothesis, whereby déjà vu is produced by an erroneous feeling of familiarity which is not in ...

  16. Recurrent diarrhea as a manifestation of temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Tomohiko Murai

    2014-01-01

    Full Text Available A woman with temporal lobe epilepsy manifesting with repeated episodes of sudden diarrhea and loss of consciousness is reported. A 63-year-old, right-handed female presented with chief complaints of sudden diarrhea and loss of consciousness for almost three decades. The first attack occurred in her 30s, and similar attacks repeated several times in a year. Her attacks comprised abrupt abdominal discomfort, diarrhea, sudden emergence of old memories relating to when she had played with her brother in her childhood, and loss of consciousness during defecation. She had no convulsion or automatism and fully recovered in a few minutes. Every time she was transferred to emergency hospital by ambulance, she had examinations such as blood test, head computed tomography, electrocardiogram, abdominal ultrasound, and electroencephalography (EEG, but no specific diagnosis was made. On admission to our hospital, vital signs, neurological examination, and blood tests did not show abnormal findings. During long-term video-EEG monitoring for 40 h, she had no habitual event. Interictal EEG showed intermittent irregular delta waves and sharp regional transients in the left anterio-midtemporal area. Sharp transients were not as outstanding from background activities as to be defined as epileptiform discharges, but they were reproducible in morphology and distribution and appeared not only in sleep but also in wakefulness. Brain magnetic resonance imaging was unremarkable. Single-photon emission computed tomography showed a decrease of blood flow in the left frontal and temporal lobes. Wechsler Adult Intelligence Scale—III showed a decline of verbal comprehension. We concluded that the patient was suffering from partial epilepsy originating from the left temporal lobe. Carbamazepine markedly improved her seizures. Temporal lobe epilepsy can manifest with diverse autonomic symptoms and signs. Abdominal sensations often herald the onset of epileptic seizures

  17. Wideband Low Side Lobe Aperture Coupled Patch Phased Array Antennas

    Science.gov (United States)

    Poduval, Dhruva

    Low profile printed antenna arrays with wide bandwidth, high gain, and low Side Lobe Level (SLL) are in great demand for current and future commercial and military communication systems and radar. Aperture coupled patch antennas have been proposed to obtain wide impedance bandwidths in the past. Aperture coupling is preferred particularly for phased arrays because of their advantage of integration to other active devices and circuits, e.g. phase shifters, power amplifiers, low noise amplifiers, mixers etc. However, when designing such arrays, the interplay between array performance characteristics, such as gain, side lobe level, back lobe level, mutual coupling etc. must be understood and optimized under multiple design constraints, e.g. substrate material properties and thicknesses, element to element spacing, and feed lines and their orientation and arrangements with respect to the antenna elements. The focus of this thesis is to investigate, design, and develop an aperture coupled patch array with wide operating bandwidth (30%), high gain (17.5 dBi), low side lobe level (20 dB), and high Forward to Backward (F/B) ratio (21.8 dB). The target frequency range is 2.4 to 3 GHz given its wide application in WLAN, LTE (Long Term Evolution) and other communication systems. Notwithstanding that the design concept can very well be adapted at other frequencies. Specifically, a 16 element, 4 by 4 planar microstrip patch array is designed using HFSS and experimentally developed and tested. Starting from mutual coupling minimization a corporate feeding scheme is designed to achieve the needed performance. To reduce the SLL the corporate feeding network is redesigned to obtain a specific amplitude taper. Studies are conducted to determine the optimum location for a metallic reflector under the feed line to improve the F/B. An experimental prototype of the antenna was built and tested validating and demonstrating the performance levels expected from simulation predictions

  18. The IceProd (IceCube Production) Framework

    International Nuclear Information System (INIS)

    Díaz-Vélez, J C

    2014-01-01

    IceProd is a data processing and management framework developed by the IceCube Neutrino Observatory for processing of Monte Carlo simulations and data. IceProd runs as a separate layer on top of middleware or cluster job schedulers and can take advantage of a variety of computing resources including grids such as EGI, OSG, and NorduGrid as well as local clusters running batch systems like HT Condor, PBS, and SGE. This is accomplished by a set of dedicated daemons which process job submission in a coordinated fashion through the use of middleware plug-ins that serve to abstract the details of job submission and job management. IceProd can also manage complex workflow DAGs across distributed computing grids in order to optimize usage of resources. We describe several aspects of IceProd's design and it's applications in collaborative computing environments. We also briefly discuss design aspects of a second generation IceProd, currently being tested in IceCube.

  19. Little Ice Age Fluctuations of Quelccaya Ice Cap, Peru

    Science.gov (United States)

    Stroup, J. S.; Kelly, M. A.; Lowell, T.

    2009-12-01

    A record of the past extents of Quelccaya Ice Cap (QIC) provides valuable information about tropical climate change from late glacial to recent time. Here, we examine the timing and regional significance of fluctuations of QIC during the Little Ice Age (LIA; ~1300-1850 AD). One prominent set of moraines, known as the Huancane I moraines, is located ~1 km from the present-day western ice cap margin and provides a near-continuous outline of the most recent advance of QIC. This moraine set was radiocarbon dated (~298 ± 134 and 831 ± 87 yr BP) by Mercer and Palacios (1977) and presented as some of the first evidence for cooling in the tropics during the Little Ice Age. Recent field investigations in the QIC region focused on refining the chronology of the Huancane I moraines. In 2008, new stratigraphic sections exposed by local lake-flooding events revealed multiple layers of peat within the Huancane I moraines. In both 2008 and 2009, samples were obtained for 10Be dating of boulders on Huancane I moraines. A combination of radiocarbon and 10Be ages indicate that the Huancane I moraines were deposited by ice cap expansion after ~3800 yr BP and likely by multiple advances at approximately 1000, 600, 400, and 200 yr BP. Radiocarbon and 10Be chronologies of the Huancane I moraines are compared with the Quelccaya ice core records (Thompson et al., 1985; 1986; 2006). Accumulation data from the ice core records are interpreted to indicate a significant wet period at ~1500-1700 AD followed by a significant drought at ~1720-1860 AD. We examine ice marginal fluctuations during these times to determine influence of such events on the ice cap extent.

  20. Arctic sea-ice ridges—Safe heavens for sea-ice fauna during periods of extreme ice melt?

    Science.gov (United States)

    Gradinger, Rolf; Bluhm, Bodil; Iken, Katrin

    2010-01-01

    The abundances and distribution of metazoan within-ice meiofauna (13 stations) and under-ice fauna (12 stations) were investigated in level sea ice and sea-ice ridges in the Chukchi/Beaufort Seas and Canada Basin in June/July 2005 using a combination of ice coring and SCUBA diving. Ice meiofauna abundance was estimated based on live counts in the bottom 30 cm of level sea ice based on triplicate ice core sampling at each location, and in individual ice chunks from ridges at four locations. Under-ice amphipods were counted in situ in replicate ( N=24-65 per station) 0.25 m 2 quadrats using SCUBA to a maximum water depth of 12 m. In level sea ice, the most abundant ice meiofauna groups were Turbellaria (46%), Nematoda (35%), and Harpacticoida (19%), with overall low abundances per station that ranged from 0.0 to 10.9 ind l -1 (median 0.8 ind l -1). In level ice, low ice algal pigment concentrations (Turbellaria, Nematoda and Harpacticoida also were observed in pressure ridges (0-200 ind l -1, median 40 ind l -1), although values were highly variable and only medians of Turbellaria were significantly higher in ridge ice than in level ice. Median abundances of under-ice amphipods at all ice types (level ice, various ice ridge structures) ranged from 8 to 114 ind m -2 per station and mainly consisted of Apherusa glacialis (87%), Onisimus spp. (7%) and Gammarus wilkitzkii (6%). Highest amphipod abundances were observed in pressure ridges at depths >3 m where abundances were up to 42-fold higher compared with level ice. We propose that the summer ice melt impacted meiofauna and under-ice amphipod abundance and distribution through (a) flushing, and (b) enhanced salinity stress at thinner level sea ice (less than 3 m thickness). We further suggest that pressure ridges, which extend into deeper, high-salinity water, become accumulation regions for ice meiofauna and under-ice amphipods in summer. Pressure ridges thus might be crucial for faunal survival during periods of

  1. Determinación de la máxima capacidad de adsorción de la tierra de arriera en la eliminación de fosfatos en soluciones acuosas

    OpenAIRE

    Cremades Oliver, Lázaro Vicente

    2013-01-01

    Los materiales existentes en el trópico como es la tierra de arriera pueden ser usados como una herramienta de biorremediación en procesos de purificación y descontaminación de aguas residuales contaminadas. El objetivo de este estudio consistió en determinar la máxima capacidad de adsorción de tierra de arriera en la eliminación de fosfatos en periodos de tiempos determinados. La metodología aplicada consistió en la extracción de fósforo adsorbido por las arcillas y la técnica de Melhich, a ...

  2. Influencia del uso de la tierra con cultivos de cacao, chakras y bosque primario, sobre la diversidad, almacenamiento de carbono y productividad en la Reserva de la Biosfera Sumaco, Ecuador.

    OpenAIRE

    Jadán Maza, Ángel Oswaldo

    2013-01-01

    La investigación se realizó en la Reserva de la Biosfera Sumaco, en la provincia del Napo, Republica del Ecuador. Se estudiaron siete sistemas de uso de la tierra: Chakras con y sin sombra, cultivos de cacao propagados por semilla con y sin sombra, cacao injertado con y sin sombra y bosque primario. Se evaluaron tres variables de respuesta: diversidad arbórea y arbustiva, almacenamiento-acumulación de carbono (C) y productividad, en los diferentes sistemas de usos de la tierra.

  3. UN MÉTODO DE GESTIÓN AMBIENTAL PARA EL TRATAMIENTO Y LA DISPOSICIÓN FINAL ADECUADA DE UN RESIDUO PELIGROSO. CASO: TIERRA FULLER CONTAMINADA CON ACEITE DIELÉCTRICO

    Directory of Open Access Journals (Sweden)

    AGUDELO EDISON ALEXANDER

    2012-11-01

    Full Text Available La gestión ambiental de un residuo peligroso comprende diferentes etapas: generación, minimización, transporte, valorización, tratamiento y disposición. Este trabajo explora dos tecnologías para el tratamiento y disposición final de un residuo peligroso (RESPEL o tierra Fuller contaminada con aceite dieléctrico: una físico-química y otra biológica. Para la tecnología físico-química se usó hexano como solvente y se alcanzaron remociones del aceite dieléctrico del orden del 87% en la tierra Fuller contaminada, con una relación tierra Fuller: solvente de 1:8 p/v, una velocidad de agitación de 100 rpm y un tiempo de contacto de 30 min. La calidad del aceite dieléctrico recuperado no es apta para su uso nuevamente en equipos eléctricos, por su baja rigidez dieléctrica, baja densidad y color desfavorable. La tierra Fuller recuperada registró una densidad aparente de 0.641 gr/ml, una densidad real de 2.231 gr/ml y una porosidad de 72.075 %, lo que indica que dicha tierra esta muy cercana en sus características físicas a la tierra Fuller limpia.Para la tecnología biológica se trató la tierra contaminada en un biorreactor biológico de tierra activada, evaluando la velocidad de agitación y el tiempo de degradación necesario para alcanzar los niveles de descontaminación adecuados que permitan disponer el residuo en un relleno sanitario convencional o una escombrera sin riesgo alguno para la salud de los ecosistemas y el ser humano. Se alcanzaron remociones en este sistema del orden de 49.68%, aunque no se alcanzó los niveles de limpieza exigidos por la Resolución 1170 de 1997 del DAMA. El resultado es importante en cuanto se creía que altas concentraciones de hidrocarburos (superiores al 10% son inhibitorias de la actividad biológica. Se hizo el seguimiento cromatográfico a 10 especies de hidrocarburos presentes en el aceite dieléctrico que son importantes dentro de este producto.

  4. Dinámica reciente de la concentración de la propiedad y uso de la tierra en Colombia. Algunas reflexiones a propósito de la especialización productiva

    OpenAIRE

    Suescún, Carlos Alberto

    2011-01-01

    La dinámica histórica de desigualdad rural en Colombia, ha estado caracterizada principalmente por una persistente concentración de la propiedad de la tierra, que en tiempo reciente ha estado impulsada por factores como el despojo de tierras y la profundización de las desigualdades en el sector rural en un contexto de violencia y narcotráfico. A estos factores estructurales, en las últimas dos décadas se han sumado dos adicionales que han profundizado las desigualdades: la especialización pro...

  5. Caracterización actual de la utilización del uso del suelo y la cobertura vegetal en la región de la Tierra Indígena Sangradouto/Volta Grande-Mato Grosso, Brasil

    Directory of Open Access Journals (Sweden)

    Fernando Shinji Kawakubo

    2012-02-01

    Full Text Available El objeto de este trabajo fue el mapear el uso y cobertura vegetal en la tierra indígena Sangradouro/Volta Grande-MT (Brasil. Para ello se emplearon técnicas de Modelo Lineal de Mezcla Espectral acompañadas por la segmentación de las imágenes sintéticas y clasificación supervisada de los componentes divididos. El cálculo de las áreas correspondientes a las clases de uso del suelo y cobertura vegetal, permitió estimar el estado actual de la tierra en el contexto ambiental.

  6. The timing of associative memory formation: frontal lobe and anterior medial temporal lobe activity at associative binding predicts memory

    Science.gov (United States)

    Hales, J. B.

    2011-01-01

    The process of associating items encountered over time and across variable time delays is fundamental for creating memories in daily life, such as for stories and episodes. Forming associative memory for temporally discontiguous items involves medial temporal lobe structures and additional neocortical processing regions, including prefrontal cortex, parietal lobe, and lateral occipital regions. However, most prior memory studies, using concurrently presented stimuli, have failed to examine the temporal aspect of successful associative memory formation to identify when activity in these brain regions is predictive of associative memory formation. In the current study, functional MRI data were acquired while subjects were shown pairs of sequentially presented visual images with a fixed interitem delay within pairs. This design allowed the entire time course of the trial to be analyzed, starting from onset of the first item, across the 5.5-s delay period, and through offset of the second item. Subjects then completed a postscan recognition test for the items and associations they encoded during the scan and their confidence for each. After controlling for item-memory strength, we isolated brain regions selectively involved in associative encoding. Consistent with prior findings, increased regional activity predicting subsequent associative memory success was found in anterior medial temporal lobe regions of left perirhinal and entorhinal cortices and in left prefrontal cortex and lateral occipital regions. The temporal separation within each pair, however, allowed extension of these findings by isolating the timing of regional involvement, showing that increased response in these regions occurs during binding but not during maintenance. PMID:21248058

  7. Declarative long-term memory and the mesial temporal lobe: Insights from a 5-year postsurgery follow-up study on refractory temporal lobe epilepsy.

    Science.gov (United States)

    Salvato, Gerardo; Scarpa, Pina; Francione, Stefano; Mai, Roberto; Tassi, Laura; Scarano, Elisa; Lo Russo, Giorgio; Bottini, Gabriella

    2016-11-01

    It is largely recognized that the mesial temporal lobe and its substructure support declarative long-term memory (LTM). So far, different theories have been suggested, and the organization of declarative verbal LTM in the brain is still a matter of debate. In the current study, we retrospectively selected 151 right-handed patients with temporal lobe epilepsy with and without hippocampal sclerosis, with a homogeneous (seizure-free) clinical outcome. We analyzed verbal memory performance within a normalized scores context, by means of prose recall and word paired-associate learning tasks. Patients were tested at presurgical baseline, 6months, 2 and 5years after anteromesial temporal lobe surgery, using parallel versions of the neuropsychological tests. Our main finding revealed a key involvement of the left temporal lobe and, in particular, of the left hippocampus in prose recall rather than word paired-associate task. We also confirmed that shorter duration of epilepsy, younger age, and withdrawal of antiepileptic drugs would predict a better memory outcome. When individual memory performance was taken into account, data showed that females affected by left temporal lobe epilepsy for longer duration were more at risk of presenting a clinically pathologic LTM at 5years after surgery. Taken together, these findings shed new light on verbal declarative memory in the mesial temporal lobe and on the behavioral signature of the functional reorganization after the surgical treatment of temporal lobe epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Sea ice-albedo climate feedback mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, J.L.; Curry, J.A. [Univ. of Colorado, Boulder, CO (United States); Ebert, E.E. [Bureau of Meterology Research Center, Melbourne (Australia)

    1995-02-01

    The sea ice-albedo feedback mechanism over the Arctic Ocean multiyear sea ice is investigated by conducting a series of experiments using several one-dimensional models of the coupled sea ice-atmosphere system. In its simplest form, ice-albedo feedback is thought to be associated with a decrease in the areal cover of snow and ice and a corresponding increase in the surface temperature, further decreasing the area cover of snow and ice. It is shown that the sea ice-albedo feedback can operate even in multiyear pack ice, without the disappearance of this ice, associated with internal processes occurring within the multiyear ice pack (e.g., duration of the snow cover, ice thickness, ice distribution, lead fraction, and melt pond characteristics). The strength of the ice-albedo feedback mechanism is compared for several different thermodynamic sea ice models: a new model that includes ice thickness distribution., the Ebert and Curry model, the Mayjut and Untersteiner model, and the Semtner level-3 and level-0 models. The climate forcing is chosen to be a perturbation of the surface heat flux, and cloud and water vapor feedbacks are inoperative so that the effects of the sea ice-albedo feedback mechanism can be isolated. The inclusion of melt ponds significantly strengthens the ice-albedo feedback, while the ice thickness distribution decreases the strength of the modeled sea ice-albedo feedback. It is emphasized that accurately modeling present-day sea ice thickness is not adequate for a sea ice parameterization; the correct physical processes must be included so that the sea ice parameterization yields correct sensitivities to external forcing. 22 refs., 6 figs., 1 tab.

  9. Middle fossa arachnoid cyst with temporal lobe agenesis accompanying isodense subdural hematoma -a case report-

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Soo; Choi, Hyung Sik; Kim, Myung Joon; Yang, Seoung Oh; Kim, Chang Jin [Capital Armed Forces General Hospital, Seongnam (Korea, Republic of)

    1987-12-15

    Cysts overlying the temporal lobes have been well described in literature. These are often associated with agenesis of the temporal lobes, and of major neurosurgical interest due to their frequent association with subdural hematoma, a combination that is rarely seen with cysts in other regions. Full features of plain, angiographic, and CT findings of arachnoid cyst with temporal lobe agenesis accompanying isodense subdural hematoma are presented, being very rare in radiologic literature.

  10. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    Energy Technology Data Exchange (ETDEWEB)

    Rademacher, J.; Seitz, R.J. [Department of Neurology, Heinrich-Heine University Duesseldorf (Germany); Aulich, A. [Department of Radiology, Heinrich-Heine University, Duesseldorf (Germany); Reifenberger, G. [Department of Neuropathology, Heinrich-Heine University, Duesseldorf (Germany); Kiwit, J.C.W. [Department of Neurosurgery, Heinrich-Heine University, Duesseldorf (Germany); Langen, K.J.; Schmidt, D. [Institute of Medicine, Research Center Juelich, Heinrich-Heine University, Duesseldorf (Germany)

    2000-06-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[{sup 123}I]iodo-{alpha}-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  11. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    International Nuclear Information System (INIS)

    Rademacher, J.; Seitz, R.J.; Aulich, A.; Reifenberger, G.; Kiwit, J.C.W.; Langen, K.J.; Schmidt, D.

    2000-01-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[ 123 I]iodo-α-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  12. Observations of significant flux closure by dual lobe reconnection

    Directory of Open Access Journals (Sweden)

    S. M. Imber

    2007-07-01

    Full Text Available We present an interval of dual lobe reconnection during which interplanetary magnetic field lines are captured by the magnetosphere by reconnecting at high latitudes in both the Northern and the Southern Hemispheres. This event was identified using measurements of the ionospheric convection flow and observations of the aurora using the SuperDARN radars and the IMAGE spacecraft. A cusp spot, characteristic of northward IMF, is clearly visible for a 30 min period enabling the ionospheric footprint of the Northern Hemisphere merging gap to be accurately determined. During the interval a strong burst of sunward flow across the dayside open/closed field line boundary (OCB is observed, which we interpret as the reconfiguration of the magnetosphere following a burst of reconnection. Noon-midnight and dawn-dusk keograms of the aurora show that the polar cap shrinks during the interval indicating that a large amount of flux was closed by the reconnection. Using the SuperDARN potential maps it is possible to calculate that the amount of flux closed during the interval is 0.13 GWb which represents approximately 10% of the pre-existing polar cap. The number of ions captured by the burst of dual lobe reconnection was calculated to be ~2.2×1031, more than sufficient to populate a cold, dense plasma sheet. That a dense plasma sheet was not subsequently observed is discussed in terms of subsequent changes in the IMF.

  13. Widespread temporo-occipital lobe dysfunction in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Loewe, Kristian; Machts, Judith; Kaufmann, Jörn; Petri, Susanne; Heinze, Hans-Jochen; Borgelt, Christian; Harris, Joseph Allen; Vielhaber, Stefan; Schoenfeld, Mircea Ariel

    2017-01-09

    Recent studies suggest that amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) lie on a single clinical continuum. However, previous neuroimaging studies have found only limited involvement of temporal lobe regions in ALS. To better delineate possible temporal lobe involvement in ALS, the present study aimed to examine changes in functional connectivity across the whole brain, particularly with regard to extra-motor regions, in a group of 64 non-demented ALS patients and 38 healthy controls. To assess between-group differences in connectivity, we computed edge-level statistics across subject-specific graphs derived from resting-state functional MRI data. In addition to expected ALS-related decreases in functional connectivity in motor-related areas, we observed extensive changes in connectivity across the temporo-occipital cortex. Although ALS patients with comorbid FTD were deliberately excluded from this study, the pattern of connectivity alterations closely resembles patterns of cerebral degeneration typically seen in FTD. This evidence for subclinical temporal dysfunction supports the idea of a common pathology in ALS and FTD.

  14. Do children with aggressive behavior have temporal lobe changes?

    International Nuclear Information System (INIS)

    Thomas, C.T.; Mishkin, F.; Goldberg, M.

    2002-01-01

    Aggressive behavior and mood disorders may afflict children. One problem is the lack of objective data to arrive at a specific clinical diagnosis. Abnormalities in neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid have been reported to play an important role in the onset of these disorders. We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred to us with the diagnosis of ADHD or autism and reported as having temper problems by their families. These patients were injected with a dose of Tc-99m HMPAO calculated according to patient age and weight and were imaged 1 hour later using a Picker camera with Fan Beam collimators. We analyzed the brain SPECT using 3D as well as the traditional transverse, coronal and sagittal images. With the help of surface rendered 3D images with a cut off of 88% (high) and 60-65% (lower value depending on the patient RCBF value), we observed increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children whose parents did not report temper problems. Increase in perfusion to the temporal lobes may indicate an association with oppositional or aggressive behavior that may be amenable to treatment. Brain SPECT may be useful not only in early diagnosis, but also in guiding appropriate therapy

  15. Do children with aggressive behavior have temporal lobe changes?

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C T; Mishkin, F; Goldberg, M [Department of Nuclear Medicine, Harbor-UCLA Medical Center, Torrance, CA (United States)

    2002-09-01

    Aggressive behavior and mood disorders may afflict children. One problem is the lack of objective data to arrive at a specific clinical diagnosis. Abnormalities in neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid have been reported to play an important role in the onset of these disorders. We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred to us with the diagnosis of ADHD or autism and reported as having temper problems by their families. These patients were injected with a dose of Tc-99m HMPAO calculated according to patient age and weight and were imaged 1 hour later using a Picker camera with Fan Beam collimators. We analyzed the brain SPECT using 3D as well as the traditional transverse, coronal and sagittal images. With the help of surface rendered 3D images with a cut off of 88% (high) and 60-65% (lower value depending on the patient RCBF value), we observed increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children whose parents did not report temper problems. Increase in perfusion to the temporal lobes may indicate an association with oppositional or aggressive behavior that may be amenable to treatment. Brain SPECT may be useful not only in early diagnosis, but also in guiding appropriate therapy.

  16. Mesial temporal lobe epilepsy - An overview of surgical techniques.

    Science.gov (United States)

    Muzumdar, Dattatraya; Patil, Manoj; Goel, Atul; Ravat, Sangeeta; Sawant, Nina; Shah, Urvashi

    2016-12-01

    Mesial temporal lobe epilepsy is one of the commonest indications for epilepsy surgery. Presurgical evaluation for drug resistant epilepsy and identification of appropriate candidates for surgery is essential for optimal seizure freedom. The anatomy of mesial temporal lobe is complex and needs to be understood in the context of the advanced imaging, ictal and interictal Video_EEG monitoring, neuropsychology and psychiatric considerations. The completeness of disconnection of epileptogenic neural networks is paramount and is correlated with the extent of resection of the mesial temporal structures. In the Indian subcontinent, a standard but extended anterior temporal lobectomy is a viable option in view of the diverse socioeconomic, cultural and pathological considerations. The maximum utilization of epilepsy surgery services in this region is also a challenge. There is a need for regional comprehensive epilepsy care teams in a tertiary care academic hospital to form centers of excellence catering to a large population. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  17. Electroencephalography in Mesial Temporal Lobe Epilepsy: A Review

    Science.gov (United States)

    Javidan, Manouchehr

    2012-01-01

    Electroencephalography (EEG) has an important role in the diagnosis and classification of epilepsy. It can provide information for predicting the response to antiseizure drugs and to identify the surgically remediable epilepsies. In temporal lobe epilepsy (TLE) seizures could originate in the medial or lateral neocortical temporal region, and many of these patients are refractory to medical treatment. However, majority of patients have had excellent results after surgery and this often relies on the EEG and magnetic resonance imaging (MRI) data in presurgical evaluation. If the scalp EEG data is insufficient or discordant, invasive EEG recording with placement of intracranial electrodes could identify the seizure focus prior to surgery. This paper highlights the general information regarding the use of EEG in epilepsy, EEG patterns resembling epileptiform discharges, and the interictal, ictal and postictal findings in mesial temporal lobe epilepsy using scalp and intracranial recordings prior to surgery. The utility of the automated seizure detection and computerized mathematical models for increasing yield of non-invasive localization is discussed. This paper also describes the sensitivity, specificity, and predictive value of EEG for seizure recurrence after withdrawal of medications following seizure freedom with medical and surgical therapy. PMID:22957235

  18. Imaging structural and functional brain networks in temporal lobe epilepsy

    Science.gov (United States)

    Bernhardt, Boris C.; Hong, SeokJun; Bernasconi, Andrea; Bernasconi, Neda

    2013-01-01

    Early imaging studies in temporal lobe epilepsy (TLE) focused on the search for mesial temporal sclerosis, as its surgical removal results in clinically meaningful improvement in about 70% of patients. Nevertheless, a considerable subgroup of patients continues to suffer from post-operative seizures. Although the reasons for surgical failure are not fully understood, electrophysiological and imaging data suggest that anomalies extending beyond the temporal lobe may have negative impact on outcome. This hypothesis has revived the concept of human epilepsy as a disorder of distributed brain networks. Recent methodological advances in non-invasive neuroimaging have led to quantify structural and functional networks in vivo. While structural networks can be inferred from diffusion MRI tractography and inter-regional covariance patterns of structural measures such as cortical thickness, functional connectivity is generally computed based on statistical dependencies of neurophysiological time-series, measured through functional MRI or electroencephalographic techniques. This review considers the application of advanced analytical methods in structural and functional connectivity analyses in TLE. We will specifically highlight findings from graph-theoretical analysis that allow assessing the topological organization of brain networks. These studies have provided compelling evidence that TLE is a system disorder with profound alterations in local and distributed networks. In addition, there is emerging evidence for the utility of network properties as clinical diagnostic markers. Nowadays, a network perspective is considered to be essential to the understanding of the development, progression, and management of epilepsy. PMID:24098281

  19. Decision making in patients with temporal lobe epilepsy.

    Science.gov (United States)

    Labudda, Kirsten; Frigge, Kristina; Horstmann, Simone; Aengenendt, Joerg; Woermann, Friedrich G; Ebner, Alois; Markowitsch, Hans J; Brand, Matthias

    2009-01-01

    The mesiotemporal lobe is involved in decision making processes because bilateral amygdala damage can cause impairments in decision making that is mainly based on the processing of emotional feedback. In addition to executive functions, previous studies have suggested the involvement of feedback processing in decision making under risk when explicit information about consequences and their probabilities is provided. In the current study, we investigated whether unilateral mesiotemporal damage, comprising of the hippocampus and/or the amygdala, results in alterations of both kinds of decision making. For this purpose, we preoperatively examined 20 patients with refractory unilateral mesiotemporal lobe epilepsy (TLE) and a comparison group (CG) of 20 healthy volunteers with the Iowa Gambling Task to assess decision making based on feedback processing, the Game of Dice Task to assess decision making under risk, and with a neuropsychological test battery. Results indicate that TLE patients performed normally in decision making under risk, but can exhibit disturbances in decision making on the Iowa Gambling Task. A subgroup analysis revealed that those patients with a preference for the disadvantageous alternatives performed worse on executive subcomponents and had seizure onset at an earlier age in comparison to the patient subgroup without disadvantageous decision making. Furthermore, disadvantageous decision making can emerge in patients with selective hippocampal sclerosis not extended to the amygdala. Thus, our results demonstrate for the first time that presurgical patients with TLE can have selective reductions in decision making and that these deficits can result from hippocampal lesions without structural amygdala abnormalities.

  20. Imaging structural and functional brain networks in temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Boris eBernhardt

    2013-10-01

    Full Text Available Early imaging studies in temporal lobe epilepsy (TLE focused on the search for mesial temporal sclerosis, as its surgical removal results in clinically meaningful improvement in about 70% of patients. Nevertheless, a considerable subgroup of patients continues to suffer from post-operative seizures. Although the reasons for surgical failure are not fully understood, electrophysiological and imaging data suggest that anomalies extending beyond the temporal lobe may have negative impact on outcome. This hypothesis has revived the concept of human epilepsy as a disorder of distributed brain networks. Recent methodological advances in non-invasive neuroimaging have led to quantify structural and functional networks in vivo. While structural networks can be inferred from diffusion MRI tractography and inter-regional covariance patterns of structural measures such as cortical thickness, functional connectivity is generally computed based on statistical dependencies of neurophysiological time-series, measured through functional MRI or electroencephalographic techniques. This review considers the application of advanced analytical methods in structural and functional connectivity analyses in TLE. We will specifically highlight findings from graph-theoretical analysis that allow assessing topological organization of brain networks. These studies have provided compelling evidence that TLE is a system disorder with profound alterations in local and distributed networks. In addition, there is emerging evidence for the utility of network properties as clinical diagnostic markers. Nowadays, a network perspective is considered to be essential to the understanding of the development, progression, and management of epilepsy.