897 resultados para end-to-end testing, javascript, application web, single-page application


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In contrast to numerous studies on the biomass of marine microphytobenthos from temperate coastal ecosystems, little is known from polar regions. Therefore, microphytobenthos biomass was measured at several coastal sites in Arctic Kongsfjorden (Spitsbergen) during the polar summer (June-August 2006). On sandy sediments, chla varied between 8 and 200 mg/m**2 and was related to water depth, current/wave exposure and geographical location. Biomass was rather independent of abiotic parameters such as sediment properties, salinity, temperature or light availability. At three stations, sediments at water depths of 3-4, 10, 15, 20 and 30 m were investigated to evaluate the effect of light availability on microalgae. Significant differences in distribution patterns of biomass in relation to deeper waters >10 m were found. The productive periods were not as distinct as phytoplankton blooms. Only at 3-4 m water depth at all three stations were two- to threefold increases of biomass measured during the investigation period. Hydrodynamic conditions seemed to be the driving force for differences in sediment colonisation by benthic microalgae. In spite of the extreme Arctic environmental conditions for algal growth, microphytobenthos biomass was comparable to marine temperate waters.

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Drake Passage is a major route for many water masses from the strong Antarctic Circumpolar Current. During the ANTXXIV-3 expedition (in 2008) the vertical distributions of dissolved and size-fractionated particulate 231Pa and thorium isotopes (230Th, 232Th and 234Th) were investigated in order to better define the scavenging regimes and the effects of the oceanic circulation on the fate of particulate material and on the Pa-Th distributions in the water column. The reversible scavenging-model applied to both 230Th and 234Th, in the upper 1500 m depth, gives estimates of the particle dynamics (settling velocities S~ 500-1300 m/y, adsorption and desorption rate constants of 0.1-0.4 1/y and 1-6 1/y respectively). Particulate 234Th/230Th activity ratio shows a depth dependence, with decreasing ratio with increasing depth in agreement with previous studies, but no relationship with particle size was found. 231Pa and thorium isotope fractionation and partition coefficients were investigated with particle size vs depth and latitude and appear to vary horizontally following a North-South gradient. This suggests that both radionuclides are mostly bound to the fine suspended particles. At Drake Passage, the 230Thxs distribution is controlled by a southward upwelling of deep water (clearly visible on the vertical section of total 230Thxs, defined as dissolved + particulate concentrations) and reversible-scavenging processes (linear increase of 230Thxs with increasing depth) with North of the Southern ACC Front, higher settling velocities and less adsorption/desorption cycles, than South of it. Distributions of dissolved and total 231Paxs also reflect the influence of the North-South upwelling but somehow this effect appears to be limited to the upper 1500 m depth of the water column. Below this depth, 231Paxs vertical profiles exhibit contrasted concentrations, with some high dissolved activities in the deep water of the stations in the northern part of the ACC and not South of the ACC. These N-S differences in dissolved 231Paxs were attributed to the different origins and scavenging history of the deep Pacific waters flowing across Drake Passage. Here at North, radionuclides-rich deep water originates from the Central Pacific, while at South, deep water derives from the Southern Pacific in which the observed low radionuclides concentrations are attributed to high opal abundance. South of the Drake Passage, high dissolved and particulate activities of 230Th and 232Th confirmed the intrusion of 230Th-rich Weddell Sea Deep Water (WSDW) close to the Antarctic Peninsula.

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Halocarbons, halogenated short-chained hydrocarbons, are produced naturally in the oceans by biological and chemical processes. They are emitted from surface seawater into the atmosphere, where they take part in numerous chemical processes such as ozone destruction and the oxidation of mercury and dimethyl sulfide. Here we present oceanic and atmospheric halocarbon data for the Peruvian upwelling obtained during the M91 cruise onboard the research vessel Meteor in December 2012. Surface waters during the cruise were characterized by moderate concentrations of bromoform (CHBr3) and dibromomethane (CH2Br2) correlating with diatom biomass derived from marker pigment concentrations, which suggests this phytoplankton group as likely source. Concentrations measured for the iodinated compounds methyl iodide (CH3I) of up to 35.4 pmol L-1, chloroiodomethane (CH2ClI) of up to 58.1 pmol L-1 and diiodomethane (CH2I2) of up to 32.4 pmol L-1 in water samples were much higher than previously reported for the tropical Atlantic upwelling systems. Iodocarbons also correlated with the diatom biomass and even more significantly with dissolved organic matter (DOM) components measured in the surface water. Our results suggest a biological source of these compounds as significant driving factor for the observed large iodocarbon concentrations. Elevated atmospheric mixing ratios of CH3I (up to 3.2 ppt), CH2ClI (up to 2.5 ppt) and CH2I2 (3.3 ppt) above the upwelling were correlated with seawater concentrations and high sea-to-air fluxes. The enhanced iodocarbon production in the Peruvian upwelling contributed significantly to tropospheric iodine levels.

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The goal of this study was to determine whether beta(1)-adrenergic receptor (AR) and beta(2)-AR differ in regulating cardiomyocyte survival and apoptosis and, if so, to explore underlying mechanisms. One potential mechanism is that cardiac beta(2)-AR can activate both G(s) and G(i) proteins, whereas cardiac beta(1)-AR couples only to G(s). To avoid complicated crosstalk between beta-AR subtypes, we expressed beta(1)-AR or beta(2)-AR individually in adult beta(1)/beta(2)-AR double knockout mouse cardiac myocytes by using adenoviral gene transfer. Stimulation of beta(1)-AR, but not beta(2)-AR, markedly induced myocyte apoptosis, as indicated by increased terminal deoxynucleotidyltransferase-mediated UTP end labeling or Hoechst staining positive cells and DNA fragmentation. In contrast, beta(2)-AR (but not beta(1)-AR) stimulation elevated the activity of Akt, a powerful survival signal; this effect was fully abolished by inhibiting G(i), G(beta gamma), or phosphoinositide 3 kinase (PI3K) with pertussis toxin, beta ARK-ct (a peptide inhibitor of G(beta gamma)), or LY294002, respectively. This indicates that beta(2)-AR activates Akt via a G(i)-G(beta gamma)-PI3K pathway. More importantly, inhibition of the G(i)-G(beta gamma)-PI3K-Akt pathway converts beta(2)-AR signaling from survival to apoptotic. Thus, stimulation of a single class of receptors, beta(2)-ARs, elicits concurrent apoptotic and survival signals in cardiac myocytes. The survival effect appears to predominate and is mediated by the G(i)-G(beta gamma)-PI3K-Akt signaling pathway.

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An aerosol time-of-flight mass spectrometer (ATOFMS) was deployed for the measurement of the size resolved chemical composition of single particles at a site in Cork Harbour, Ireland for three weeks in August 2008. The ATOFMS was co-located with a suite of semi-continuous instrumentation for the measurement of particle number, elemental carbon (EC), organic carbon (OC), sulfate and particulate matter smaller than 2.5 μm in diameter (PM2.5). The temporality of the ambient ATOFMS particle classes was subsequently used in conjunction with the semi-continuous measurements to apportion PM2.5 mass using positive matrix factorisation. The synergy of the single particle classification procedure and positive matrix factorisation allowed for the identification of six factors, corresponding to vehicular traffic, marine, long-range transport, various combustion, domestic solid fuel combustion and shipping traffic with estimated contributions to the measured PM2.5 mass of 23%, 14%, 13%, 11%, 5% and 1.5% respectively. Shipping traffic was found to contribute 18% of the measured particle number (20–600 nm mobility diameter), and thus may have important implications for human health considering the size and composition of ship exhaust particles. The positive matrix factorisation procedure enabled a more refined interpretation of the single particle results by providing source contributions to PM2.5 mass, while the single particle data enabled the identification of additional factors not possible with typical semi-continuous measurements, including local shipping traffic.

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Humans are profoundly affected by the surroundings which they inhabit. Environmental psychologists have produced numerous credible theories describing optimal human environments, based on the concept of congruence or “fit” (1, 2). Lack of person/environment fit can lead to stress-related illness and lack of psychosocial well-being (3). Conversely, appropriately designed environments can promote wellness (4) or “salutogenesis” (5). Increasingly, research in the area of Evidence-Based Design, largely concentrated in the area of healthcare architecture, has tended to bear out these theories (6). Patients and long-term care residents, because of injury, illness or physical/ cognitive impairment, are less likely to be able to intervene to modify their immediate environment, unless this is designed specifically to facilitate their particular needs. In the context of care settings, detailed design of personal space therefore takes on enormous significance. MyRoom conceptualises a personalisable room, utilising sensoring and networked computing to enable the environment to respond directly and continuously to the occupant. Bio-signals collected and relayed to the system will actuate application(s) intended to positively influence user well-being. Drawing on the evidence base in relation to therapeutic design interventions (7), real-time changes in ambient lighting, colour, image, etc. respond continuously to the user’s physiological state, optimising congruence. Based on research evidence, consideration is also given to development of an application which uses natural images (8). It is envisaged that actuation will require machine-learning based on interpretation of data gathered by sensors; sensoring arrangements may vary depending on context and end-user. Such interventions aim to reduce inappropriate stress/ provide stimulation, supporting both instrumental and cognitive tasks.

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New pollen and radiocarbon data from an 8.6-m coastal section, Cape Shpindler (69°43' N; 62°48' E), Yugorski Peninsula, document the latest Pleistocene and Holocene environmental history of this low Arctic region. Twelve AMS 14C dates indicate that the deposits accumulated since about 13,000 until 2000 radiocarbon years BP. A thermokarst lake formed ca. 13,000-12,800 years BP, when scarce arctic tundra vegetation dominated the area. By 12,500 years BP, a shallow lake existed at the site, and Arctic tundra with Poaceae, Cyperaceae, Salix, Saxifraga, and Artemisia dominated nearby vegetation. Climate was colder than today. Betula nana became dominant during the Early Preboreal period about 9500 years BP, responding to a warm event, which was one of the warmest during the Holocene. Decline in B. nana and Salix after 9500 years BP reflects a brief event of Preboreal cooling. A subsequent increase in Betula and Alnus fruticosa pollen percentages reflects amelioration of environmental conditions at the end of Preboreal period (ca. 9300 years BP). A decline in arboreal taxa later, with a dramatic increase in herb taxa, reflects a short cold event at about 9200 years BP. The pollen data reflect a northward movement of tree birch, peaking at the middle Boreal period, around 8500 years BP. Open Betula forest existed on the Kara Sea coast of the Yugorski Peninsula during the Atlantic period (8000-4500 years BP), indicating that climate was significantly warmer than today. Deteriorating climate around the Atlantic-Subboreal boundary (ca. 4500 years BP) is recorded by a decline in Betula percentages. Sedimentation slowed at the site, and processes of denudation and/or soil formation started at the beginning of the Subatlantic period, when vegetation cover on Yugorski Peninsula shifted to near-modern assemblages.

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Recent coccoliths from 52 surface sediment samples recovered from the south-eastern South Atlantic were examined qualitatively and quantitatively in order to assess the controlling mechanisms for their distribution patterns, such as ecological and preservational factors, and their role as carbonate producers. Total coccolith abundances range from 0.2 to 39.9 coccoliths*10**9/ g sediment. Four assemblages can be delineated by their coccolith content characterising the northern Benguela, the middle to southern Benguela, the Walvis Ridge and the deeper water. Distinctions are based on multivariate ordination techniques applied on the relative abundances of the most abundant taxa, Emiliania huxleyi, Calcidiscus leptoporus, Gephyrocapsa spp., Coccolithus pelagicus and subtropical to tropical species. The coccolith distribution seems to be temperature and nutrient controlled co-varying with the seaward extension of the upwelling filament zone in the Benguela. A preservation index (CEX') based on the differential dissolution behaviour of the delicate E. huxleyi and Gephyrocapsa ericsonii versus the robust C. leptoporus is applied in order to detect the position of the coccolith lysocline. Although some samples were recognised as dissolution-affected, the distribution of the coccoliths in the surface-sediments reflects the different oceanographic surface-water conditions. Mass estimations of the coccolith carbonate reveal coccoliths to be only minor contributors to the carbonate preserved in the surface sediments. The mean computed coccolith carbonate content is 17 wt.%, equivalent to a mean contribution of 23% to the bulk carbonate.

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We reviewed the paleoceanographic application of the carbon isotope composition of planktic foraminifera. Major controls on the distribution of d13C of dissolved CO2 (d13CSCO2) in the modern ocean are photosynthesis-respiration cycle, isotopic fractionation during air-sea exchange, and circulation. The carbon isotope composition of surface waters is not recorded without perturbations by planktic foraminifera. Besides d13CSCO2 of the surrounding seawater, the d13C composition of planktic foraminifera is affected by vital effects, the water depth of calcification and postdepositional dissolution. We compared several high-resolution (>10cm/ka) carbon isotope records from the Southern Ocean, the Benguela upwelling system, and the tropical Atlantic. In the Southern Ocean, carbon isotope values are about 1.2 per mil lower during the LGM and up to 1.7 per mil lower during the last deglaciation, when compared to the Holocene. These depletions might be explained with a combination of a subsurface nutrient enrichment and reduced air-sea exchange due to an increased stratification of surface waters. In the Benguela Upwelling system, waters originating in the south are upwelled. While the deglacial minimum is transferred and recorded in its full extent in the d13C record of Globigerina bulloides, glacial values show only little changes. This might suggest, that the lower glacial d13C values of high-latitude surface waters are not upwelled off Namibia, or that G. bulloides records post-upwelling conditions, when increased seasonal production has already increased surface-water d13C. Synchronous to the d13C depletions in high latitudes, low d13C values were recorded in Globigerinoides sacculifer during the LGM and during the last deglaciation in the nutrient-depleted western equatorial Atlantic. Hence, part of the glacial-interglacial variability presumably transferred from high to low latitudes seems to be related to changes in thermodynamic fractionation. The variability in d13C is lowest in the northernmost core M35003-4 from the eastern Caribbean, implying that the Antarctic Intermediate Water might have acted as a conduit to transfer the deglacial minimum to tropical surface waters.

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Surface samples, mostly from abyssal sediments of the South Atlantic, from parts of the equatorial Atlantic, and of the Antarctic Ocean, were investigated for clay content and clay mineral composition. Maps of relative clay mineral content were compiled, which improve previous maps by showing more details, especially at high latitudes. Large-scale relations regarding the origin and transport paths of detrital clay are revealed. High smectite concentrations are observed in abyssal regions, primarily derived from southernmost South America and from minor sources in Southwest Africa. Near submarine volcanoes of the Antarctic Ocean (South Sandwich, Bouvet Island) smectite contents exhibit distinct maxima, which is ascribed to the weathering of altered basalts and volcanic glasses. The illite distribution can be subdivided into five major zones including two maxima revealing both South African and Antarctic sources. A particularly high amount of Mg- and Fe-rich illites are observed close to East Antarctica. They are derived from biotite-bearing crystalline rocks and transported to the west by the East Antarctic Coastal Current. Chiorite and well-crystallized dioctaedral illite are typical minerals enriched within the Subantarctic and Polarfrontal-Zone but of minor importance off East Antarctica. Kaolinite dominates the clay mineral assemblage at low latitudes, where the continental source rocks (West Africa, Brazil) are mainly affected by intensive chemical weathering. Surprisingly, a slight increase of kaolinite is observed in the Enderby Basin and near the Filchner-Ronne Ice shelf. The investigated area can be subdivided into ten, large-scale clay facies zones with characteristic possible source regions and transport paths. Clay mineral assemblages of the largest part of the South Atlantic, especially of the western basins are dominated by chlorite and illite derived from the Antarctic Peninsula and southernmost South America and supported by advection within the Circumantarctic Deep Water flow. In contrast, the East Antarctic provinces are relatively small. Assemblages of the eastern basins north of 30°S are strongly influenced by African sources, controlled by weathering regimes on land and by a complex interaction of wind, river and deep ocean transport. The strong gradient in clay mineral composition at the Brazilian slope indicate a relatively low contribution of tropically derived assemblages to the western basins.

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Rock magnetic measurements were performed on sediments above 20 meters below seafloor (mbsf) (general) and above 2.5 mbsf (detailed) at Sites 1109, 1110, and 1115 (Ocean Drilling Program Leg 180) in the western Woodlark Basin. Rock magnetic parameters imply the presence of magnetite as a principal magnetic mineral in the sediments. The hysteresis ratios lay in the pseudo-single domain field and generally showed the trend close to that for the mixture of single domain and multidomain magnetite The sediments in the oxidized zones at the top at Sites 1109 and 1115 provided a different trend in the logarithmic plot of the hysteresis ratios, and the oxidized samples were characterized by higher coercivity.

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Within a larger program research work is being done on the history of settlement and landscape of the 'Siedlungskammer' Flögeln and the adjacent area. The 'Siedlungskammer' consists of an isolated pleistocene sand ground (Geest-island) surroundet by bogs. Starting from the edge of the Geest, near which large-scale archaeological excavations are carried out, three raised bog profiles were taken at 300, 500 and 4000 m off the prehistoric settlement. They were investigated by means of pollen analysis, and reflect in a decreasing way the activities of man on the Geestisland. Another pollen diagram from the nearby fen peat was worked out for comparison. At the same time it helped to date back a prehistoric sand path to the Roman period. The pollen diagrams cover the vegetational history without gaps from the early Atlantic period to modern times. The vegetation was decisively determined by the poor soils of this area. T'he pollen diagrams give evidence of the activity of settlers since the Neolithic age, with some gaps in the beginning, but later continuously from the middle of the Bronze age until the early migration period. The influence of the nearby settlement, which existed from the Birth of Christ to the 4/5th century, comes out distinctly. Among the cereals which were then cultivated here, there also was rye, at least in the 4/5th century, but most probably already during the Roman period. Besides that people cultivated barley, oats, and flax. The settlement break during the so-called dark ages between the 4/5th century and the time about 800 A.D. was confirmed by pollen analysis. During this time the area was once more covered by forests. The fluctuations of man's activities during the late Middle Ages and modern times, as they are made visible by pollen analysis, correspond to historically wellknown developments.

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This paper will be based on my continuing research on planning and housing development in London. It will focus on the proposals in the Government’s Housing and Planning Bill, which are likely to be enacted in Spring 2016. It will review the evidence of potential spatial impacts in terms of the supply of existing affordable homes and the location and affordability of new supply. This will be related to a review of the alternative development options for London’s growth in the context of the Mayor of London’s draft 2050 Infrastructure Plan. The paper will analyse the potential impact of new Government policy and legislation on whether London’s housing requirements can be delivered in accordance with the objectives of sustainable planning and social justice, and will also consider the constraints on the ability of the new Mayor of London, to be elected in May 2016 to achieve manifesto commitments.

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This paper will examine familiar reasons for including the teaching of intercultural competence within Language Teaching before adding some less familiar ones. It will focus in particular on the question of how far intercultural competence can be learned when students are formally studying languages and how far such competence needs to be acquired autono-mously. It will though also ask to what extent being initiated to the very varied facets of in-tercultural competence during formal language study plays an important role in allowing ef-fective autonomous acquisition to take place. The paper will conclude that a significant part of the intercultural development that students need to undertake if they are to be able to communicate effectively in a foreign language must happen autonomously, but that it is, nonetheless, vital that language courses at least sow the seeds of intercultural learning in ways that will facilitate autonomous learning. As such, language courses, if they are genuinely to meet student needs, should incorporate elements of intercultural training. The paper also concludes by outlining the type of empirical research that would need to be carried out for these claims to be fully substantiated.

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Physical location of data in cloud storage is a problem that gains a lot of attention not only from the actual cloud providers but also from the end users' who lately raise many concerns regarding the privacy of their data. It is a common practice that cloud service providers create replicate users' data across multiple physical locations. However, moving data in different countries means that basically the access rights are transferred based on the local laws of the corresponding country. In other words, when a cloud service provider stores users' data in a different country then the transferred data is subject to the data protection laws of the country where the servers are located. In this paper, we propose LocLess, a protocol which is based on a symmetric searchable encryption scheme for protecting users' data from unauthorized access even if the data is transferred to different locations. The idea behind LocLess is that "Once data is placed on the cloud in an unencrypted form or encrypted with a key that is known to the cloud service provider, data privacy becomes an illusion". Hence, the proposed solution is solely based on encrypting data with a key that is only known to the data owner.