991 resultados para Berthaud, 1783


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This article provides the first substantial survey of early archaeological research in Egypt’s Dakhleh Oasis. In addition to providing a much-needed survey of research, this study embeds Dakhleh’s regional research history within a broader archaeological research framework. Moreover, it explores the impact of contemporaneous historical events in Egypt and Europe upon the development of archaeology in Dakhleh. This contextualised approach allows us to trace influences upon past research trends and their impacts upon current research and approaches, as well as suggest directions for future research.

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The complaints on the adoption of Arabic by the Copts that are voiced by the Apocalypse of Pseudo-Samuel have often been quoted as the expiring words of the dying Coptic language. This article seeks to show that they are not to be taken so literally, and that they should rather be inserted in the context of a rift within the medieval Coptic church over the question of language choice, and beyond this, over that of accommodation with the Muslims. The use of Arabic by the episcopal church of Miṣr and by some prominent figures around it, which was linked to their proximity to the Fatimid court, was resented and denounced by more traditional circles, centred on the Patriarchate and on some important monasteries such as the one at Qalamūn where the Apocalypse was written. The suggestion is also made that the text is contemporary with the beginning of Coptic literary production in Arabic and with the introduction of Egyptian Christians at the caliphal court, namely in the last quarter of the tenth century, at the time of Severus ibn al-Muqqafa‘.

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Current state-of-the-art climate models fail to capture accurately the path of the Gulf Stream and North Atlantic Current. This leads to a warm bias near the North American coast, where the modelled Gulf Stream separates from the coast further north, and a cold anomaly to the east of the Grand Banks of Newfoundland, where the North Atlantic Current remains too zonal in this region. Using an atmosphere-only model forced with the sea surface temperature (SST) biases in the North Atlantic, we consider the impact they have on the mean state and the variability in the North Atlantic European region in winter. Our results show that the SST errors produce a mean sea-level pressure response that is similar in magnitude and pattern to the atmospheric circulation errors in the coupled climate model. The work also suggests that errors in the coupled model storm tracks and North Atlantic Oscillation, compared to reanalysis data, can also be explained partly by these SST errors. Our results suggest that both the error in the Gulf Stream separation location and the path of the North Atlantic Current around the Grand Banks play important roles in affecting the atmospheric circulation. Reducing these coupled model errors could improve significantly the representation of the large-scale atmospheric circulation of the North Atlantic and European region.

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Classical Greek and Roman influence on the material culture of Central Asia and northwestern India is often considered in the abstract. This article attempts to examine the mechanisms of craft production and movement of artisans and objects which made such influence possible, through four case studies: (1) Mould-made ceramics in Hellenistic eastern Bactria; (2) Plaster casts used in the production of metalware from Begram; (3) Terracotta figurines and the moulds used to produce them, from various archaeological sites; and (4) Mass production of identical gold adornments in the nomadic tombs from Tillya Tepe. The implications of such techniques for our understanding of the development of Gandhāran art are also discussed.

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We analyse the ability of CMIP3 and CMIP5 coupled ocean–atmosphere general circulation models (CGCMs) to simulate the tropical Pacific mean state and El Niño-Southern Oscillation (ENSO). The CMIP5 multi-model ensemble displays an encouraging 30 % reduction of the pervasive cold bias in the western Pacific, but no quantum leap in ENSO performance compared to CMIP3. CMIP3 and CMIP5 can thus be considered as one large ensemble (CMIP3 + CMIP5) for multi-model ENSO analysis. The too large diversity in CMIP3 ENSO amplitude is however reduced by a factor of two in CMIP5 and the ENSO life cycle (location of surface temperature anomalies, seasonal phase locking) is modestly improved. Other fundamental ENSO characteristics such as central Pacific precipitation anomalies however remain poorly represented. The sea surface temperature (SST)-latent heat flux feedback is slightly improved in the CMIP5 ensemble but the wind-SST feedback is still underestimated by 20–50 % and the shortwave-SST feedbacks remain underestimated by a factor of two. The improvement in ENSO amplitudes might therefore result from error compensations. The ability of CMIP models to simulate the SST-shortwave feedback, a major source of erroneous ENSO in CGCMs, is further detailed. In observations, this feedback is strongly nonlinear because the real atmosphere switches from subsident (positive feedback) to convective (negative feedback) regimes under the effect of seasonal and interannual variations. Only one-third of CMIP3 + CMIP5 models reproduce this regime shift, with the other models remaining locked in one of the two regimes. The modelled shortwave feedback nonlinearity increases with ENSO amplitude and the amplitude of this feedback in the spring strongly relates with the models ability to simulate ENSO phase locking. In a final stage, a subset of metrics is proposed in order to synthesize the ability of each CMIP3 and CMIP5 models to simulate ENSO main characteristics and key atmospheric feedbacks.

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Colour-magnitude diagrams (CMDs) of the Small Magellanic Cloud (SMC) star cluster NGC 419, derived from Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) data, reveal a well-delineated secondary clump located below the classical compact red clump typical of intermediate-age populations. We demonstrate that this feature belongs to the cluster itself, rather than to the underlying SMC field. Then, we use synthetic CMDs to show that it corresponds very well to the secondary clump predicted to appear as a result of He-ignition in stars just massive enough to avoid e(-)-degeneracy settling in their H-exhausted cores. The main red clump instead is made of the slightly less massive stars which passed through e(-) degeneracy and ignited He at the tip of the red giant branch. In other words, NGC 419 is the rare snapshot of a cluster while undergoing the fast transition from classical to degenerate H-exhausted cores. At this particular moment of a cluster`s life, the colour distance between the main-sequence turn-off and the red clump(s) depends sensitively on the amount of convective core overshooting, Lambda(c). By coupling measurements of this colour separation with fits to the red clump morphology, we are able to estimate simultaneously the cluster mean age (1.35(-0.04)(+0.11) Gyr) and overshooting efficiency (Lambda(c) = 0.47(-0.04)(+0.14)). Therefore, clusters like NGC 419 may constitute important marks in the age scale of intermediate-age populations. After eye inspection of other CMDs derived from HST/ACS data, we suggest that the same secondary clump may also be present in the Large Magellanic Cloud clusters NGC 1751, 1783, 1806, 1846, 1852 and 1917.

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The high dependence of herbivorous insects on their host plants implies that plant invaders can affect these insects directly, by not providing a suitable habitat, or indirectly, by altering host plant availability. In this study, we sampled Asteraceae flower heads in cerrado remnants with varying levels of exotic grass invasion to evaluate whether invasive grasses have a direct effect on herbivore richness independent of the current disturbance level and host plant richness. By classifying herbivores according to the degree of host plant specialization, we also investigated whether invasive grasses reduce the uniqueness of the herbivorous assemblages. Herbivorous insect richness showed a unimodal relationship with invasive grass cover that was significantly explained only by way of the variation in host plant richness. The same result was found for polyphagous and oligophagous insects, but monophages showed a significant negative response to the intensity of the grass invasion that was independent of host plant richness. Our findings lend support to the hypothesis that the aggregate effect of invasive plants on herbivores tends to mirror the effects of invasive plants on host plants. In addition, exotic plants affect specialist insects differently from generalist insects; thus exotic plants affect not only the size but also the structural profile of herbivorous insect assemblages.

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The reaction of cis-[RuCl2(dppb)(N-N)], dppb = 1,4-bis(diphenylphosphino)butane, complexes with the ligand HSpymMe(2), 4,6-dimethyl-2-mercaptopyrimidine, yielded the cationic complexes [Ru(SpymMe(2))(dppb)(N-N)]PF6, N-N = bipy (1) and Me-bipy (2), bipy = 2,2`-bipyridine and Me-bipy = 4,4`dimethyl-2,2`-bipyridine, which were characterized by spectroscopic and electrochemical techniques and X-ray crystallography and elemental analysis. Additionally, preliminary in vitro tests for antimycobacterial activity against Mycobacterium tuberculosis H37Rv ATCC 27264 and antitumor activity against the MDA-MB-231 human breast tumor cell line were carried out on the new complexes and also on the precursors cis-[RuCl2(dppb)(N-N)], N-N = bipy (3) and Me-bipy (4) and the free ligands dppb, bipy, Me-bipy and SpymMe(2). The minimal inhibitory concentration (MIC) of compounds needed to kill 90% of mycobacterial cells and the IC50 values for the antitumor activity were determined. Compounds 1-4 exhibited good in vitro activity against M. tuberculosis, with MIC values ranging between 0.78 and 6.25 mu g/mL, compared to the free ligands (MIC of 25 to >50 mu g/mL) and the drugs used to treat tuberculosis. Complexes I and 2 also showed promising antitumor activity, with IC50 values of 0.46 +/- 0.02 and 0.43 +/- 0.08 mu M, respectively, against MDA-MB-231 breast tumor cells. (C) 2008 Elsevier Inc. All rights reserved.

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This paper generalizes the methodology of Cat and Brown [Cai, T., Brown, L.D., 1998. Wavelet shrinkage for nonequispaced samples. The Annals of Statistics 26, 1783-1799] for wavelet shrinkage for nonequispaced samples, but in the presence of correlated stationary Gaussian errors. If the true function is a member of a piecewise Holder class, it is shown that, even for long memory errors, the rate of convergence of the procedure is almost-minimax relative to the independent and identically distributed errors case. (c) 2008 Elsevier B.V. All rights reserved.

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We study the 1-parameter Wecken problem versus the restricted Wecken problem, for coincidence free pairs of maps between surfaces. For this we use properties of the function space between two surfaces and of the pure braid group on two strings of a surface. When the target surface is either the 2-sphere or the torus it is known that the two problems are the same. We classify most pairs of homotopy classes of maps according to the answer of the two problems are either the same or different when the target is either projective space or the Klein bottle. Some partial results are given for surfaces of negative Euler characteristic. (C) 2010 Elsevier B.V. All rights reserved.

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We report an Mg-based metallic glass/titanium interpenetrating phase composite in which constituent phases form a homogeneously interconnected network. The porous titanium constrains shear bands propagation thoroughly and promotes shear bands branching and intersection subsequently. The homogeneous phase distribution promotes regularly distributed local shear deformation and leads to a uniform deformation for the composites. Moreover, the interpenetrating phase structure introduces a mutual-reinforcement between metallic glass and titanium. Therefore, the composite exhibits excellent mechanical performance with compressive fracture strength of 1783 MPa and fracture strain of 31%.

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Students look forward to summer because usually it means a break from formal and non-formal education. Formal education refers to education in formal educational institutions, such as pre-schools, primary, secondary and tertiary educational institutions and other registered training organisations. Non-formal education refers to organised educational activity outside the established formal system, that is intended to deliver a defined set of learning objectives to an identifiable group of learners (Chemistry in Australia, October 2014, page 33). Informal education refers to all learning outside the formal non-formal educational system; informal education is often associated with life-long learning as it can include reading non-fiction books and scholarly articles, viewing documentaries and other informal professional development. Informal education can also include travel to other countries and climates. Social constructivist theory maintains that learning occurs in social settings; conversely, most learners are limited by their cultural experiences. For example, Australian students have little first-hand experience of sublimation, but this is commonly observed in very cold climates when frost, ice or snow apparently “disappears” as it sublimes to water vapour, without passing through the liquid state. A favourite summertime activity is to go to the movies, especially in air-conditioned cinemas on a hot day or night. Watching movies are a form of virtual travel, and many educators make use of movies to illustrate chemistry concepts. Some movie producers want a sense of authenticity and work hard to get the details right, even though those details might be incidental to the main plot. For example, in Centurion, Roman soldiers fail in their rescue attempt, and are taunted by the Picts for stupidity -- they would have succeeded if they had only realised that metal become brittle in the cold. Another favourite example comes from The Lord of the Rings: The Two Towers, when Bilbo, Samwise and Gollum are crossing the Dead Marshes and see lights that appear to float over the Marshes. These wills-o-the-wisp have been known for centuries, and was the subject of a debate between George Washington and his officers. Washington and Thomas Paine, “the Father of the American Revolution”, believed that the lights were due to a flammable gas released from the marsh, while Washington’s officers believed that the lights were due to a flammable liquid on the surface of the marsh. On Guy Fawkes Night, 5 November, 1783, the Washington-Paine experiment showed that when mud at the bottom of a river was disturbed, bubbles of flammable gas rose to the surface of the water. (Unknown to Washington and Paine, Alessandro Volta had performed a similar experiment in 1776.) A problem with informal education is that it is often unguided. Students may find it difficult to discern the difference between scientific reality and an artistic distortion of reality in novels and movies. Educators have an important role here. If we only teach facts and concepts, learners will be dependent on a teacher. If however, we foster students’ curiosity and ability to exercise judgement, they will be able to learn for themselves, not just during the summer, but also in every season of every year.

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Pautado nessa perspectiva de valorização do patrimônio industrial na região do ABC, esse texto volta-se para as relações entre indústria, lazer e memória. Tem como foco o tema do lazer e do entretenimento como uma das construções patrimoniais da sociedade industrial. O Palácio de Mármore do Moinho São Jorge representa um caso em que tais relações se conjugam. Dessa forma, propõe-se com esse artigo, apontar as relações existentes entre industrialização e lazer no ABC no período de 1950/60, tomando como ponto de partida as lembranças das pessoas que viveram à época.