Age determination of sediment cores off western Spitsbergen

The Late Weichselian glacial history of the continental shelf off western Spitsbergen is discussed, based on acoustic sub-bottom records and sediment cores. The outer part of Isfjorden and the inner shelf to the west of this fjord are characterized by a thin veneer (10-20 m) of glacigenic sediments and absence of ice-marginal features. Towards the outer shelf the sediment thickness increases significantly, and exceeds 500 m at the shelf edge. Possible moraine complexes were identified in this outer part. Sediment cores from the inner shelf sampled a firm diamicton, interpreted as till, beneath soft glaciomarine sediments. Radiocarbon dates on shells from the clay resting directly on the till, suggest an age of around 12,500 yrs B.P. for the base of the marine sequence. We argue that grounded ice covered the sites shortly before. In contrast to suggestions that the fjords and coast were partly ice free during the Late Weischselian, we conclude that the ice must have reached out onto the continental shelf.

Age determination of sediments off western Svalbard

Late Quaternary sediment yields from the Isfjorden drainage area (7327 km**2), a high arctic region on Svalbard characterized by an alpine landscape, have been reconstructed by using seismic stratigraphy supported by sediment core analysis. The sediments that accumulated in the fjord during and since deglaciation can be divided into three stratigraphic units. The volumes of these units were determined and converted into sediment yield rates averaged over the drainage basin. During deglaciation, 13 to 10 ka, the sediment yield was ~860 tons(t)/km**2/yr. In the early Holocene it decreased to 190 t/km**2/yr, and then increased to 390t/km**2/yr during the late Holocene Little Ice Age. When normalized to the approximate glacierized area, these rates correspond to a sediment yield of ~800 t/km**2/yr . Sediment yield from non-glacierized parts of the drainage is estimated to be 35 t/km**2/yr. At times when ice advanced to the shelf edge, sediment was scoured from the fjord and deposited on the outer shelf and in a well-defined deep sea fan. Between 200 ka and 13 ka, 328 km**3 of sediment accumulated here, corresponding to a mean sediment yield rate of 335 t/km**2/yr. This is broadly consistent with calculations based on the above rates of sediment yield in glacierized and non-glacierized areas, and on estimates, based on glacial geology, of the temporal variation in degree of glacierization over the past 200 kyr. These figures indicate that much of the glacigenic sediment on the shelf and slope was eroded from the uplands of Svalbard by small glaciers during interstadials and interglacials. The sediments were temporarily stored in the fjord prior to redeposition on the shelf and slope during ice sheet advance. Taken into consideration, such redisposition of pre-eroded material will reduce estimates of primary ice sheet erosion rate.

Reprodutibilidade da medida ambulatorial da pressão arterial em pacientes hipertensos com diabete melito tipo 2

OBJETIVO: Avaliar a reprodutibilidade e o efeito placebo sobre a monitorização ambulatorial da pressão arterial (MAPA) (SpaceLabs-90207). MÉTODOS: Mensurou-se a PA no consultório e por meio de duas MAPA, realizadas em um intervalo de 1 a 10 meses (média de 4,9 meses), de 26 pacientes com diabetes tipo 2 e hipertensão. Onze pacientes (G1) realizaram as duas MAPA sem medicação anti-hipertensiva por 15 dias, enquanto o G2 (N = 15) fez a segunda MAPA em uso de placebo pelo mesmo período. RESULTADOS: Ao avaliarmos os coeficientes de variação (CV) da PA sistólica na vigília (PASV), PA diastólica na vigília (PADV), PA sistólica nas 24h (PAS24h) e PA diastólica nas 24h (PAD24h), encontramos valores de 4,6%, 3,9%, 5,0% e 4,0% no G1 e 4,3%, 5,1%, 3,7% e 5,1% no G2, respectivamente. Quanto ao CV da PA sistólica e diastólica durante o sono (PASS e PADS), encontramos 7,7% e 8,2% para G1, e 5,6% e 6,3% para G2, respectivamente. O CV da freqüência cardíaca na vigília e durante o sono foram: G1 = 5,9% e 9,0%, G2 = 6,9% e 5,8%, respectivamente. Analisando o total dos pacientes, todas as variáveis mostraram fortes correlações entre a primeira e a segunda MAPA (PASV, r=0,76; P<0,001; PADV, r=0,65; p<0,001; PAS24h, r=0,77; p<0,001; PAD24h, r=0,70; p<0,001; PASS, r=0,62; p<0,001; PADS, r=0,52; p<0,01). Ocorreram também correlações entre a PA sistólica e a diastólica de consultório e a PAS24h e PAD24h (r=0,65; p<0,001; r=0,57; p<0,01). CONCLUSÃO: A média dos níveis pressóricos avaliados pela MAPA apresentou boa reprodutibilidade e esses não foram afetados pelo efeito placebo.

Increase in skeletal muscle protein content by the ß-2 selective adrenergic agonist clenbuterol exacerbates hypoalbuminemia in rats fed a low-protein diet

This investigation examined how the nutritional status of rats fed a low-protein diet was affected when the animals were treated with the ß-2 selective agonist clenbuterol (CL). Males (4 weeks old) from an inbred, specific-pathogen-free strain of hooded rats maintained at the Dunn Nutritional Laboratory were used in the experiments (N = 6 rats per group). CL treatment (Ventipulmin, Boehringer-Ingelheim Ltd., 3.2 mg/kg diet for 2 weeks) caused an exacerbation of the symptoms associated with protein deficiency in rats. Plasma albumin concentrations, already low in rats fed a low-protein diet (group A), were further reduced in CL rats (A = 25.05 ± 0.31 vs CL = 23.64 ± 0.30 g/l, P<0.05). Total liver protein decreased below the level seen in either pair-fed animals (group P) or animals with free access to the low-protein diet (A = 736.56 ± 26 vs CL = 535.41 ± 54 mg, P<0.05), whereas gastrocnemius muscle protein was higher than the values normally described for control (C) animals (C = 210.88 ± 3.2 vs CL = 227.14 ± 1.7 mg/g, P<0.05). Clenbuterol-treated rats also showed a reduction in growth when compared to P rats (P = 3.2 ± 1.1 vs CL = -10.2 ± 1.9 g, P<0.05). This was associated with a marked decrease in fat stores (P = 5.35 ± 0.81 vs CL = 2.02 ± 0.16 g, P<0.05). Brown adipose tissue (BAT) cytochrome oxidase activity, although slightly lower than in P rats (P = 469.96 ± 16.20 vs CL = 414.48 ± 11.32 U/BAT x kg body weight, P<0.05), was still much higher than in control rats (C = 159.55 ± 11.54 vs CL = 414.48 ± 11.32 U/BAT x kg body weight, P<0.05). The present findings support the hypothesis that an increased muscle protein content due to clenbuterol stimulation worsened amino acid availability to the liver and further reduced albumin synthesis causing exacerbation of hypoalbuminemia in rats fed a low-protein diet.

Huerta escolar 88-89 : proyecto huerta escolar.

La Asociación para la Investigación y el Estudio de la Deficiencia Mental, CEPRI, crea en el centro un huerto escolar como recurso didáctico y alternativa a la estricta actividad escolar, ya que éste permite no sólo el desarrollo de la Educación Ambiental, sino también la adquisición de habilidades y destrezas de las diferentes áreas (cognitiva, social, lenguaje, sensoriomotriz y plástica). Los objetivos son: trabajar los contenidos y destrezas de las áreas curriculares; conocer el nombre de las plantas y flores y hacer un seguimiento del proceso vegetativo de las mismas; aprender a relacionar los frutos del huerto con los alimentos que ellos consumen; respetar y cuidar la naturaleza; y fomentar el trabajo en equipo, responsabilizándose y compartiendo el material. La experiencia se centra por una parte en las labores normales en el huerto: preparación del terreno, siembra, cultivo, riego, recolección, etc.; y por otra, en la realización de actividades de aula, de carácter complementario, derivadas de los trabajos en el huerto: elaboración de fichas de plantas, recogida de información, dibujos y collages, etc. Además, es importante señalar que a través de estas actividades se ejercitan una serie de técnicas o habilidades que impregnan todo el currículo de Educación Especial (diálogo, conversación, convivencia, habilidades sociales, destrezas básicas, motricidad, etc.). La evaluación de la experiencia se basa en la observación continua (grabación de videos) mediante guías. En la memoria se incluye una valoración individual de cada alumno y un análisis de las tareas realizadas.

Memoria de educación compensatoria : curso 87-88.

Memoria que recoge aquellos aspectos que más destacan como logros de las actuaciones del programa de Educación Compensatoria y resalta los temas pendientes que se considera que necesita de una solución urgente en algunos casos y a medio en otros. El objetivo del programa de Educación Compensatoria es la desaparición de las desigualdades del acceso al sistema educativo por parte de grupos de individuos ya sean estas por razones económicas, sociales o de lugar de residencia. De ahí que se centre en las zonas rurales, en las aulas ocupacionales para jóvenes desescolarizados, minorías culturales y en la población itinerante. Asimismo cabe señalar que en el desarrollo del programa del curso 87-88 influyeron 2 hechos: 1) que el curso 87-88 ha estado marcado por el debate sobre la nueva ordenación del sistema educativo cuyos documentos se difundieron, leyeron y discutieron por el profesorado y por los equipos del programa, y 2) y en la segunda parte del curso por el conflicto del profesorado con la huelga y malestar generado entre el colectivo docente y las autoridades del Ministerio de Educación y Ciencia.

Age determination of sediment cores from the western Svalbard margin

The deglaciation of the continental shelf to the west of Spitsbergen and the main fjord, Isfjorden, is discussed based on sub-bottom seismic records and sediment cores. The sea floor on the shelf to the west of Isfjorden is underlain by less than 2 m of glaciomarine sediments over a firm diamicton interpreted as till. In central Isfjorden up to 10 m of deglaciation sediments were recorded, whereas in cores from the innermost tributary, Billefjorden, less than a meter of ice proximal sediments was recognized between the till and the 'normal' Holocene marine sediments. We conclude that the Barents Sea Ice Sheet terminated along the shelf break during the Late Weichselian glacial maximum. Radiocarbon dates from the glaciomarine sediments above the till indicate a stepwise deglaciation. Apparently the ice front retreated from the outermost shelf around 14.8 ka. A dramatic increase in the flux of line-grained glaciomarine sediments around 13 ka is assumed to reflect increased melting and/or current activity due to a climatic warming. This second stage of deglaciation was interrupted by a glacial readvance culminating on the mid-shelf area shortly after 12.4 ka. The glacial readvance, which is correlated with a simultaneous readvance of the Fennoscandian ice sheet along the western coast of Norway, is attributed to the so-called 'Older Dryas' cooling event in the North Atlantic region. Following this glacial readvance the outer part of Isfjorden became rapidly deglaciated around 12.3 ka. During the Younger Dryas the inner fjord branches were occupied by large outlet glaciers and possibly the ice front terminated far out in the main fjord. The remnants of the Barents Sea Ice Sheet melted quickly away as a response to the Holocene warming around 10 ka.

Proposed Gulf of Alaska/Cook Inlet lease sale 88 : final environmental impact statement /

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