943 resultados para Simonides, ca. 556-467 B.C.
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Aquest article presenta el resultat del procés d’implementació del portafoli manual combinat amb el portafoli electrònic, el qual se li donarà el nom de Portafoli mixt, com a estratègia didà ctica inclosa per primera vegada al primer curs de grau dels estudis d’infermeria, concretament en l’assignatura d’anatomofisiologia
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Este trabajo presenta el diseño e implementación de un programa progresivo de rehabilitación basado en los ejercicios musculares del suelo pélvico, incorporando el trabajo muscular de fuerza contrarresistencia. El disenño del estudio es casi experimental.La muestra es de 33 participantes en fase de tratamiento. Las variables de estudio son las antropométricas, las relacionadas con la evolución de la incontinencia urinaria(IU (intensidad, dificultad, frecuencia y limitación de las actividades),la obesidad, fatiga y dolor,la fuerza muscular y la calidad de vida(CdV). Para evaluar el cambio intrasujeto se tomaron medidas pretest(semana 0)y postest(semana24. En el análisis estadÃstico se utilizan las pruebas t Student-Fisher, Wilcoxon oU de Mann Whitney y el test del w2. El análisis se realiza con el programa SPSS versión 15. El nivel de significación escogido es del 5%. Al finalizar las 24 semanas del programa se identifica una disminución significativa de las variables antropométricas Ãndice de cintura cadera (p¼0,003), perÃmetro de cintura(pr0,001) y porcentaje de masa de grasa(pr0,001); de las variables de IU: intensidad(pr0,0001), frecuencia y dificultad y su relación con la limitación de las actividades (pr0,0001), asà como la relación existente entre la mejora de IU y la mejora de la CdV(p¼0,039). Queda cientÃficamente demostrada la eficacia del programa progresivo de fuerza para disminuir la IU. La mejora de la CdV del hombre mayor con cáncer de prósstata viene mediada por la mejora de la continencia urinaria
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Sediments play a fundamental role in the behaviour of contaminants in aquatic systems. Various processes in sediments, eg adsorption-desorption, oxidation-reduction, ion exchange or biological activities, can cause accumulation or release of metals and anions from the bottom of reservoirs, and have been recently studied in Polish waters [1-3]. Sediment samples from layer A: (1 divided by 6 cm depth in direct contact with bottom water); layer B: (7 divided by 12 cm depth moderate contact); and layer C: (12+ cm depth, in theory an inactive layer) were collected in September 2007 from six sites representing different types of hydrological conditions along the Dobczyce Reservoir (Fig. l). Water depths at the sampling points varied from 3.5 to 21 m. We have focused on studying the distribution and accumulation of several heavy metals (Cr, Pb, Cd, Cu and Zn) in the sediments. The surface, bottom and pore water (extracted from sediments by centrifugation) samples were also collected. Possible relationships between the heavy-metal distribution in sediments and the sediment characteristics (mineralogy, organic matter) as well as the Fe, Mn and Ca content of sediments, have been studied. The 02 concentrations in water samples were also measured. The heavy metals in sediments ranged from 19.0 to 226.3 mg/kg of dry mass (ppm). The results show considerable variations in heavy-metal concentrations between the 6 stations, but not in the individual layers (A, B, C). These variations are related to the mineralogy and chemical composition of the sediments and their pore waters.
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Previous studies have shown an inverse correlation between zooid size in cheilostome bryozoans and ambient water temperature. This relationship underlies the MART technique which uses intracolonial variation in zooid size to predict mean annual range in temperature experienced by bryozoan colonies during their life. Here we apply the MART technique to study Early and Mid Pliocene bryozoans from Central America (Panama, Costa Rica), the USA (Florida, South Carolina, North Carolina, Virginia) and the UK (Suffolk) to reconstruct palaeoseasonality across a range of latitudes for the North Atlantic during the Pliocene Epoch. Compared to the present-day, our analyses suggest greater seasonality (ca 4.5 degrees C) in the southern Caribbean at the time of Cayo Agua Formation deposition (ca 4.25 Ma), in keeping with inferred upwelling prior to the closure of the isthmian barrier at 2.7 Ma. Bryozoans also indicate seasonal upwelling on the Gulf Coast of Florida in a similar manner to the present-day. Because upwelling can be highly localised and prone to spatial and temporal variation in the Gulf of Mexico today, it contributes little to a broad understanding of Pliocene North Atlantic waters. However, MART estimates for the coastal plain region indicate a general reduction in the annual range in temperature relative to the present, suggesting that the colder surface waters that today reach south to Cape Hatteras had less influence in Early to Mid Pliocene times. These results, along with evidence from other proxies, strongly support reduced seasonality and warmer conditions along the eastern seaboard of the USA in the Early to Mid Pliocene. Finally, the MART estimates amongst Coralline Crag localities provide evidence for an increased annual range in temperature in the southern North Sea than at present. Our study shows that bryozoan MART estimates provide a powerful, independent proxy for palaeoseasonality and is the first to demonstrate that the MART technique can be applied to infer palaeoclimates across a wide range of latitudes focusing on a variety of geological formations and geographical regions. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.
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A new strategy for the synthesis of sesquiterpenoids of the furanoeremophilane family was developed in which the tricyclic nucleus was assembled in an A + C -> A - C -> A - B - C sequence. The A - C connection was made via coupling of a cyclohexenylmethyl bromide with a stannylfuran under "ligandless" Stille conditions, and the key cyclization which closed ring B was accomplished with complete stereocontrol by intramolecular formylation of a 2-silylfuran in the presence of trimethylsilyl triflate. This route was used to complete the first total syntheses of the furanoeremophilane 6-hydroxyeuryopsin and the eremophilenolides toluccanolide A and toluccanolide C, as well as a formal synthesis of 1,10-epoxy-6-hydroxyeuryopsin.
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In this Paper, we study the invariant intervals, the global attractivity of the equilibrium points, and the asymptotic behavior of the solutions of the difference equation x(n) = ax(n-1) + bx(n-2) / c + dx(n-1)x(n-2), n =1, 2, ..., where a greater than or equal to 0, b, c, d > 0. (C) 2004 Elsevier Inc. All rights reserved.
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Archaeological research has addressed imperial frontiers for more than a century. Romanists, in particular, have engaged in exploring frontiers from economic, militaristic, political, and (more recently) social vantages. This article suggests that we also consider the dialogue between space and social perception to understand imperial borderland developments. In addition to formulating new theoretical approaches to frontiers, this contribution represents the first comprehensive overview of both the documentary sources and the archaeological material found in Egypt's Great Oasis during the Roman period (ca. 30 B.C.E. to the sixth century C.E.). A holistic analysis of these sources reveals that Egypt's Great Oasis, which consisted of two separate but linked oases, served as a conceptual, physical, and human buffer zone for the Roman empire. This buffer zone protected the "ordered" Nile Valley inhabitants from the "chaotic" desert nomads, who lived just beyond the oases. This conclusion suggests that nomads required specific imperial frontier policies and that these policies may have been ideological as well as economic and militaristic.
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The inhibitory effect of hydrogen peroxide (H(2)O(2)) on glucose-stimulated insulin secretion was previously reported. However, the precise mechanism involved was not systematically investigated. In this study, the effects of low concentrations of H(2)O(2) (5-10 mu mol/L) on glucose metabolism, intracellular calcium ([Ca(2+)](i)) oscillations, and dynamic insulin secretion in rat pancreatic islets were investigated. Low concentrations of H(2)O(2) impaired insulin secretion in the presence of high glucose levels (16.7 mmol/L). This phenomenon was observed already after 2 minutes of exposure to H(2)O(2). Glucose oxidation and the amplitude of [Ca(2+)](i); oscillations were dose-dependently suppressed by H(2)O(2). These findings indicate that low concentrations of H(2)O(2) reduce insulin secretion in the presence of high glucose levels via inhibition of glucose metabolism and consequent impairment in [Ca(2+)](i); handling. (C) 2010 Elsevier Inc. All rights reserved.
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Zircon recrystallization is a common process during high-grade metamorphism and promotes partial or complete resetting of the original isotopic and chemical characteristics of the mineral and thus complicates U-Pb geochronological interpretation. In Central Brazil, this complexity may be illustrated by three composite mafic-ultramafic intrusions metamorphosed under amphibolite-to-granulite conditions. Their ages of emplacement and metamorphic ages have been a matter of controversy for the last thirty years. The Serra da Malacacheta and Barro Alto complexes make up the southernmost of these layered bodies and four samples from distinct rock types were investigated in order to verify the consequences of metamorphic alteration of zircon for U-Pb dating. Cathodoluminescent imaging reveals internal features which are typical of concomitant dissolution-reprecipitation processes, such as convolute zoning and inward-moving recrystallization fronts, even in samples in which partially preserved igneous textures are observed. Due to this extensive alteration, LA-ICPMS U-Pb isotopic analysis yielded inconclusive data. However, in situ Hf isotopic and trace-element analyses help to clarify the real meaning of the geochronological data. Low Lu/Hf (<0.004) and homogeneous (176)Hf/(177)Hf(t) values imply that the zircon populations within individual samples have crystallized in a single episode, despite the observed variations in age values. Trace element signatures of zircon grains from garnet-bearing samples reveal that they were unreactive to the development of the peak metamorphism mineral assemblage and, thus, the main chemical feature in such grains is attributed to a coupled dissolution-reprecipitation process. However, in the Cafelandia amphibolite an additional alteration process is identified, probably related to the influx of late-stage fluids. Combined isotopic and geochemical investigation on zircon grains allowed the distinction of two magmatic events. The first corresponds to the crystallization of the Serra da Malacacheta Complex and characterizes a juvenile magmatism at similar to 1.3 Ga. The younger episode, recognized in the Barro Alto Complex, is dated at ca. 800 Ma and is represented by mafic and ultramafic rocks showing intense contamination with continental crust, implying that the emplacement took place, most likely, in a continental back-arc setting. Altered zircon domains as well as titanite grains date the metamorphic event at ca. 760-750 Ma. (C) 2011 Elsevier B.V. All rights reserved.
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We conducted a multi-stage household cluster survey to calculate hepatitis B vaccine coverage among children 18-30 months of age in 27 Brazilian cities. Hepatitis B vaccine is administered at birth, 1 month and 6 months of age by Brazil`s national immunization program. Among 17,749 children surveyed, 40.2% received a birth dose within one day of birth, 94.8% received at least one dose of hepatitis B vaccine, and 86.7% completed the three-dose series by 12 months of age. Increased coverage with the birth dose and administration of hepatitis B in combination with diphtheria-tetanus-pertussis-Haemophilus influenzae type b antigens could improve protection against hepatitis B. (C) 2009 Elsevier Ltd. All rights reserved.
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In this paper, we prove that if a Banach space X contains some uniformly convex subspace in certain geometric position, then the C(K, X) spaces of all X-valued continuous functions defined on the compact metric spaces K have exactly the same isomorphism classes that the C(K) spaces. This provides a vector-valued extension of classical results of Bessaga and Pelczynski (1960) [2] and Milutin (1966) [13] on the isomorphic classification of the separable C(K) spaces. As a consequence, we show that if 1 < p < q < infinity then for every infinite countable compact metric spaces K(1), K(2), K(3) and K(4) are equivalent: (a) C(K(1), l(p)) circle plus C(K(2), l(q)) is isomorphic to C(K(3), l(p)) circle plus (K(4), l(q)). (b) C(K(1)) is isomorphic to C(K(3)) and C(K(2)) is isomorphic to C(K(4)). (C) 2011 Elsevier Inc. All rights reserved.
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Syftet med föreliggande rapport har varit att visa på de grundläggande egenskaperna för solfångare med interna reflektorer. Vidare tjänar rapporten syftet att ge en bild av dagsläget inom detta område och därigenom fungera som en utgångspunkt för forskning och utveckling kring solfångare med interna reflektorer för svenskt bruk. Arbetet har därför till stor del gått ut på att leta referenser genom tidskrifter och databaser.Den stora fördelen med CPC-solfångare, som är den klart dominerande typen av solfångare med interna reflektorer, består i dess låga värmeförluster, vilket gör dem attraktiva speciellt vid högre driftstemperaturer. De optiska egenskaperna hos olika typer av CPC-solfångare har grundligt studerats sedan mitten av 70-talet, medan studier av värmeförluster varit mer begränsad. Idag har forskningen och intresset för CPC-solfångare mattats av något, men fortsatt forskning pågår t ex i ett flertal länder, t ex USA, Israel, NordIrland och Japan. Endast en kommersiell tillverkare av CPC-solfångare har hittats (Portugal), vilken dock upphört p g a yttre ekonomiska faktorer. Japans CPC-teknologi anses stå närmast kommersiellt genombrott.Idag har utvecklingen av CPC-solfångare inriktats mot i huvudsak två koncept:1. Stationära lågkoncentrerande CPC-solfångare för produktion av värme i området 60-100 grader C. Dessa konstruktioner är ofta enkla och man försöker minimera kostnaderna för dessa konstruktioner genom att minimera behovet av t ex reflektorer och isolering. Syftet med dessa är att konkurera med plana solfångare vilka producerar värme i samma temperaturintervall. Typiska solfångarparametrar 5 som rapporteras för denna typ är UL < 3.0 W/m2 ,°C och n0 = 0.65-0.75.2. Stationära lågkoncentrerande CPC-solfångare för produktion av värme i området 100-300 grader C. Ofta bygger dessa på olika teknik för evakuering av absorbatorn, antingen genom att omsluta cirkulära absorbatorer med glasrör eller genom att införa CPC-reflektorer i heatpipes. Syftet med dessa är ofta att på ett billigt sätt producera högtemperaturvärme för olika industriprocesser, och därmed konkurera med koncentrerande solfångare typ paraboliska tråg eller traditionella heat-pipes.Beräkningar av vad en Svensk CPC-solfångare, baserad på de plana absorbatorer som finns på marknaden idag, kan prestera visar att årsutbytet av energi är jämförbart med de bästa svenska plana solfångaren som finns på marknaden idag då driftstemperaturen är ca 60-65 °C. För högre driftstemperaturer ökar skillnaden till CPC-solfångarens fördel. Vidare visas att årsutbytet har en jämnare fördelning över året jämfört, med vad en plan solfångare med samma prestanda har. Den högre prestandan vid höga driftstemperaturer och den jämnare fördelningen av energiproduktion över året gör solfångare med CPC-reflektorer intressanta för större solfångarfält, kopplade till nät med höga returtemperaturer och/eller solvärmesystem med säsongslager.Det är dock brist på undersökningar av värmeförluster i CPC-solfångare med låga koncentrationer och med plana absorbatorer, vilket är av intresse ifall de svenska erfarenheterna av plana solfångare skall tas tillvara. Potentialen med ytterligare reduktion av värmeförlusterna genom att införa extra konvektionshinder i kombination med plan absorbator har inte heller undersökts tillräckligt.
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Comparou-se a produção de sementes de grama-batatais em Latossol vermelho Escuro com ou sem adição de sulfato de amônio (4g de N/m²), superfosfato simples (50g de P2O5/m²), cloreto de potássio (15g de K2O/m²), esterco de equino (10 litros/m²) e calcário dolomÃtico (220 g/m²). As produções foram avaliadas através de número de espigas por área, peso total de sementes, peso de sementes puras, relação entre peso de sementes puras e peso total de sementes, peso de 1000 sementes puras, peso total de sementes por espiga, peso de sementes puras por espiga, porcentagem de germinação das sementes e velocidade de emergência das plântulas. Foram determinados os teores de nitrogênio, fósforo, potássio, cálcio, magnésio, enxofre, boro, cobre, ferro, manganês e zinco na matéria seca de folhas e sementes. Verificou-se que a produção de sementes, tanto em quantidade como em qualidade, foi influenciada pela nutrição mineral. As porcentagens mais elevadas de carbono no solo estiveram associadas a maior quantidade e melhor qualidade das sementes produzidas. As melhores produções de sementes correspondem aos nÃveis mais baixos de fósforo, potássio, cálcio e zinco nas folhas. Verificou-se serem importantes nas caracterÃsticas avaliadas as seguintes relações entre teores de nutrientes nas folhas ou nas sementes: N/P, P/Ca, P/Mg, P/S, P/Zn, K/Ca, K/Mg, K/B, Ca/Mg, Ca/B, Fe/Mn, Zn/Cu, Zn/Fe e Zn/Mn. Nas maiores produções, as sementes apresentaram concentrações menores de nitrogênio, boro e cobre, e mais elevadas de cálcio. As sementes de melhor qualidade apresentaram maiores concentrações de zinco e menores de boro. A aplicação de adubos ou calcário dolomÃtico não melhorou significativamente a produção de sementes.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)