45 resultados para National Collection of Fine Arts (U.S.)

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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We present results from the international field campaign DAURE (Detn. of the sources of atm. Aerosols in Urban and Rural Environments in the Western Mediterranean), with the objective of apportioning the sources of fine carbonaceous aerosols. Submicron fine particulate matter (PM1) samples were collected during Feb.-March 2009 and July 2009 at an urban background site in Barcelona (BCN) and at a forested regional background site in Montseny (MSY). We present radiocarbon (14C) anal. for elemental and org. carbon (EC and OC) and source apportionment for these data. We combine the results with those from component anal. of aerosol mass spectrometer (AMS) measurements, and compare to levoglucosan-based ests. of biomass burning OC, source apportionment of filter data with inorg. compn. + EC + OC, submicron bulk potassium (K) concns., and gaseous acetonitrile concns. At BCN, 87 % and 91 % of the EC on av., in winter and summer, resp., had a fossil origin, whereas at MSY these fractions were 66 % and 79 %. The contribution of fossil sources to org. carbon (OC) at BCN was 40 % and 48 %, in winter and summer, resp., and 31 % and 25 % at MSY. The combination of results obtained using the 14C technique, AMS data, and the correlations between fossil OC and fossil EC imply that the fossil OC at Barcelona is ∼47 % primary whereas at MSY the fossil OC is mainly secondary (∼85 %). Day-to-day variation in total carbonaceous aerosol loading and the relative contributions of different sources predominantly depended on the meteorol. transport conditions. The estd. biogenic secondary OC at MSY only increased by ∼40 % compared to the order-of-magnitude increase obsd. for biogenic volatile org. compds. (VOCs) between winter and summer, which highlights the uncertainties in the estn. of that component. Biomass burning contributions estd. using the 14C technique ranged from similar to slightly higher than when estd. using other techniques, and the different estns. were highly or moderately correlated. Differences can be explained by the contribution of secondary org. matter (not included in the primary biomass burning source ests.), and/or by an over-estn. of the biomass burning OC contribution by the 14C technique if the estd. biomass burning EC/OC ratio used for the calcns. is too high for this region. Acetonitrile concns. correlate well with the biomass burning EC detd. by 14C. K is a noisy tracer for biomass burning. [on SciFinder(R)]

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During winter 2013, extremely high concentrations (i.e., 4–20 times higher than the World Health Organization guideline) of PM2.5 (particulate matter with an aerodynamic diameter < 2.5 μm) mass concentrations (24 h samples) were found in four major cities in China including Xi'an, Beijing, Shanghai and Guangzhou. Statistical analysis of a combined data set from elemental carbon (EC), organic carbon (OC), 14C and biomass-burning marker measurements using Latin hypercube sampling allowed a quantitative source apportionment of carbonaceous aerosols. Based on 14C measurements of EC fractions (six samples each city), we found that fossil emissions from coal combustion and vehicle exhaust dominated EC with a mean contribution of 75 ± 8% across all sites. The remaining 25 ± 8% was exclusively attributed to biomass combustion, consistent with the measurements of biomass-burning markers such as anhydrosugars (levoglucosan and mannosan) and water-soluble potassium (K+). With a combination of the levoglucosan-to-mannosan and levoglucosan-to-K+ ratios, the major source of biomass burning in winter in China is suggested to be combustion of crop residues. The contribution of fossil sources to OC was highest in Beijing (58 ± 5%) and decreased from Shanghai (49 ± 2%) to Xi'an (38 ± 3%) and Guangzhou (35 ± 7%). Generally, a larger fraction of fossil OC was from secondary origins than primary sources for all sites. Non-fossil sources accounted on average for 55 ± 10 and 48 ± 9% of OC and total carbon (TC), respectively, which suggests that non-fossil emissions were very important contributors of urban carbonaceous aerosols in China. The primary biomass-burning emissions accounted for 40 ± 8, 48 ± 18, 53 ± 4 and 65 ± 26% of non-fossil OC for Xi'an, Beijing, Shanghai and Guangzhou, respectively. Other non-fossil sources excluding primary biomass burning were mainly attributed to formation of secondary organic carbon (SOC) from non-fossil precursors such as biomass-burning emissions. For each site, we also compared samples from moderately to heavily polluted days according to particulate matter mass. Despite a significant increase of the absolute mass concentrations of primary emissions from both fossil and non-fossil sources during the heavily polluted events, their relative contribution to TC was even decreased, whereas the portion of SOC was consistently increased at all sites. This observation indicates that SOC was an important fraction in the increment of carbonaceous aerosols during the haze episode in China.

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The (art) collection of Archduke Ernest of Austria (1553-1595) is widely unknown when it comes to early-modern Habsburg collections. Ernest, younger brother of Emperor Rudolf II (b. 1552) and educated at the Madrid court, was appointed Governor-General of the Netherlands by King Philip II of Spain, his uncle, in summer 1593. Ernest relocated his court from Vienna to Brussels in early 1594 and was welcomed there with lavish festivities: the traditional Blijde Inkomst, Joyous Entry, of the new sovereign. Unfortunately, the archduke died in February 1595 after residing in Brussels for a mere thirteen months. This investigation aims to shed new light on the archduke and his short-lived collecting ambitions in the Low Countries, taking into account that he had the mercantile and artistic metropolis Antwerp in his immediate reach. I argue, that his collecting ambitions can be traced back to one specific occasion: Ernest’s Joyous Entry into Antwerp in June 1594. There the archduke received a series of six paintings of Pieter Bruegel the Elder (1525/30-1569) known as The Months (painted in 1565), hanging today in separate locations in Vienna, New York and Prague. These works of art triggered Ernest’s collecting ambitions and prompted him to focus mainly on works of art and artefacts manufactured at or traded within the Netherlands during the last eight months of his lifetime. Additionally, it will be shown that the archduke was inspired by the paintings’ motifs and therefore concentrated on acquiring works of art depicting nature and landscape scenes from the 1560s and 1590s. On the basis of the archduke’s recently published account book (Kassabuch) and of the partially published inventory of his belongings, it becomes clear that Ernest of Austria must be seen in line with the better-known Habsburg collectors and that his specific collection of “the painted Netherlands” can be linked directly to his self-fashioning as a rightful sovereign of the Low Countries.

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Neonatal sepsis causes high mortality and morbidity in preterm infants, but less is known regarding the long-term outcome after sepsis. This study aimed to determine the impact of sepsis on neurodevelopment at 2 years' corrected age in extremely preterm infants.

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Eosinophils are blood cells that are often found in high numbers in the tissues of allergic conditions and helminthic parasite infections. The pathophysiologic roles that eosinophils may serve in other human "eosinophil-associated" diseases remain obscure.