955 resultados para Instrumental techinique
Resumo:
Recent fully relativistic calculations of radiative rates and electron impact excitation cross-sections for FeXIII are used to generate emission-line ratios involving 3s23p2-3s3p3 and 3s23p2-3s23p3d transitions in the 170-225 and 235-450 Å wavelength ranges covered by the Solar Extreme-Ultraviolet Research Telescope and Spectrograph (SERTS). A comparison of these line ratios with SERTS active region observations from rocket flights in 1989 and 1995 reveals generally very good agreement between theory and experiment. Several new FeXIII emission features are identified, at wavelengths of 203.79, 259.94, 288.56 and 290.81 Å. However, major discrepancies between theory and observation remain for several FeXIII transitions, as previously found by Landi and others, which cannot be explained by blending. Errors in the adopted atomic data appear to be the most likely explanation, in particular for transitions which have 3s23p3d1D2 as their upper level. The most useful FeXIII electron-density diagnostics in the SERTS spectral regions are assessed, in terms of the line pairs involved being (i) apparently free of atomic physics problems and blends, (ii) close in wavelength to reduce the effects of possible errors in the instrumental intensity calibration, and (iii) very sensitive to changes in Ne over the range 108-1011cm-3. It is concluded that the ratios which best satisfy these conditions are 200.03/202.04 and 203.17/202.04 for the 170-225 Å wavelength region, and 348.18/320.80, 348.18/368.16, 359.64/348.18 and 359.83/368.16 for 235-450 Å.
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Results of the search of the periodic changes of the 530.3 nm line intensity emitted by selected structures of the solar corona in the frequency range 1-10 Hz are presented. A set of 12 728 images of the section of the solar corona extending from near the north pole to the south-west were taken simultaneously in the 530.3 nm ("green") line and white-light with the Solar Eclipse Coronal Imaging System (SECIS) during the 143-seconds- long totality of the 1999 August 11 solar eclipse observed in Shabla, Bulgaria. The time resolution of the collected data is better than 0.05 s and the pixel size is approximately 4 arcsec. Using classical Fourier spectral analysis tools, we investigated temporal changes of the local 530.3 nm coronal line brightness in the frequency range 1-10 Hz of thousands of points within the field of view. The various photometric and instrumental effects have been extensively considered. We did not find any indisputable, statistically significant evidence of periodicities in any of the investigated points (at significance level alpha = 0.05).
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The aim of this paper is to recognize the images that prospective elementary school teachers have about citizenship and citizenship education in school. The qualitative methodology with an ethnographic approach is used for that deep interview of ethnographic kind and analysis of institutional documents, for example, curricula, course syllabus and graduated profi le. The revision of documents helps to a better understanding of discourses. The analysis of the corpus obtained after the application of the paradigm of codifi cation proposed in the established theory. As the principal fi ndings we way point out that the concept of citizens that is common among prospective elementary school teachers is reduced to the school environment because they consider that the promotion of citizenship helps to the incorporation of children to society, thus reproducing a propaedeutic view of education.
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This article examines the relationship of the body with a musical instrument; specifically it looks at the vital threshold conditions that occur during the interplay of voice and instrument. By examining the work ‘IKAS’ (1982) for solo saxophone by German composer Hans-Joachim Hespos, the unusual timbral relationships created between vocal and instrumental sounds are exposed. I argue that this particular work highlights the performer/instrument relation as one marked by Gilles Deleuze’s notion of the workings of a machine and a machine’s relation to a ‘flow’, in particular a machine’s function with view to the break in the flow. By turning towards Deleuze’s concept of the machine, this article offers a slightly different vocabulary for music analysis, one that more easily encompasses certain works of the twentieth century, specifically those that are more timbre- than pitch-based.
Resumo:
Los avances que están produciéndose en el ámbito académico con el surgimiento de herramientas de la Web 2.0 y el empleo masivo por parte de los estudiantes de la redes sociales para comunicarse entre ellos, está haciendo que el panorama educativo se encuentre ante unos desafíos a los que tiene que dar respuesta. La investigación que aquí se presenta tuvo como objetivo principal analizar el estado del empleo de la redes sociales por parte alumnado universitario, así como los posibles malos hábitos y usos problemáticos de las mismas. Se utilizó como instrumento de recogida de información un cuestionario “ad hoc” con un total de 23 ítems. Se concluye que el alumnado en general no posee malos hábitos en el empleo de las redes sociales, igualmente los resultados obtenidos ponen de manifiesto que su utilización no está plenamente integrada en las instituciones universitarias de educación superior, así como que los estudiantes no las emplean/usan como herramienta fundamental para las resolución de cuestiones académicas.
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Concentrations of the coccidiostat nicarbazin as low as 2 mg/kg in feed can result in violative drug residues arising in poultry liver. A lateral flow device (LFD) was developed for the detection of contaminating concentrations of nicarbazin following solvent extraction of poultry feeds. Test results, as determined by both visual and instrumental measurement, are available within minutes. For 22 feed samples, nicarbazin-free and fortified at 2 mg/kg, the % relative inhibition ranged from 0 to 45% and from 53 to 85%, respectively. Nicarbazin contamination at the critical concentration (2 mg/kg) can be determined in all cases providing the sampling is representative. A wide range of feed samples taken at a mill that incorporated nicarbazin into poultry feed were analyzed. Data generated for these samples by both the LFDs and a mass spectrometric method were compared, and a significant correlation was achieved.
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The subiculum is in a pivotal position governing the output of the hippocampal formation. Despite this, it is a rather under-explored and sometimes ignored structure. Here, we discuss recent data indicating that the subiculum participates in a wide range of neurocognitive functions and processes. Some of the functions of subiculum are relatively well-known-these include providing a relatively coarse representation of space and participating in, and supporting certain aspects of, memory (particularly in the dynamic bridging of temporal intervals). The subiculum also participates in a wide variety of other neurocognitive functions too. however. Much less well-known are roles for the subiculum, and particularly the ventral subiculum, in the response to fear, stress and anxiety, and in the generation of motivated behaviour (particularly the behaviour that underlies drug addiction and the response to reward). There is an emerging suggestion that the subiculum participates in the temporal control of behaviour. It is notable that these latter findings have emerged from a consideration of instrumental behaviour using operant techniques; it may well be the case that the use of the watermaze or similar spatial tasks to assess subicular function (on the presumption that its functions are very similar to the hippocampus proper) has obscured rather than revealed neurocognitive functions of subiculum. The anatomy of subiculum suggests it participates in a rather subtle fashion in a very broad range of functions, rather than in a relatively more isolated fashion in a narrower range of functions, as might be the case for
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A new kind of photographic representation, called movement-image is proposed and discussed to record the visual experience of the journey through urban highways. It consists of performing long exposure photographic shots while the track is traversed, thus registering a time-panorama which includes landscape signs and inner spaces of the ways involved. This proposal is linked to the limitations of representing these expressways, if they are understood as structures of instrumental origin, where the resulting experience comes from moving at high speed through the territory. In al almost all cases the aesthetic approach or urban integration with the city and landscape are excluded. In this sense, although such structures may be an opportunity to collect, build and colonize the urban landscape, the lack of adequate representation of the phenomenon causes a difficulty in its understanding and transformation. The options for representation using photography is assumed, knowing its own particular tradition in the use of long exposures, for the expression of the mobile, and the multiple visual attention, divided or weakened.
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Reconstruction of hydroclimate variability is an important part of understanding natural climate change on decadal to millennial timescales. Peatland records reconstruct 'bog surface wetness' (BSW) changes, but it is unclear whether it is a relative dominance of precipitation or temperature that has driven these variations over Holocene timescales. Previously, correlations with instrumental climate data implied that precipitation is the dominant control. However, a recent chironomid inferred July temperature record suggested temperature changes were synchronous with BSW over the mid-late Holocene. This paper provides new analyses of these data to test competing hypotheses of climate controls on bog surface wetness and discusses some of the distal drivers of large-scale spatial patterns of BSW change. Using statistically based estimates of uncertainty in chronologies and proxy records, we show a correlation between Holocene summer temperature and BSW is plausible, but that chronologies are insufficiently precise to demonstrate this conclusively. Simulated summer moisture deficit changes for the last 6000 years forced by temperature alone are relatively small compared with observations over the 20th century. Instrumental records show that summer moisture deficit provides the best explanatory variable for measured water table changes and is more strongly correlated with precipitation than with temperature in both Estonia and the UK. We conclude that BSW is driven primarily by precipitation, reinforced by temperature, which is negatively correlated with precipitation and therefore usually forces summer moisture deficit in the same direction. In western Europe, BSW records are likely to be forced by changes in the strength and location of westerlies, linked to large-scale North Atlantic ocean and atmospheric circulation. (C) 2009 Elsevier Ltd. All rights reserved.
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"In this special issue's opening essay, Martin Dowling devotes almost half of "'Thought-Tormented Music': Joyce and the Music of the Irish Revival" to what he calls "the situation of music in the Irish literary revival." He focuses chiefly on 1904, which was both an intensely productive period for the revival movement and a year chock-full of crucial events and decisions for Joyce. Drawing on the works of Pierre Bourdieu and Jaques Lacan, Dowling explores the revivalists' efforts to "de-anglicize" Irish music, to remove foreign influences that distorted the "pure tradition of Irish song," and to achieve an improbable harmony between the music favoured by the disappearing Anglo-Irish aristocracy and the Irish-speaking peasantry. Inevitably, disputes occurred over what constituted "authentic" Irish music. Factions quarrelled over whether pristine Irish music existed in the Atlantic seaboard or more inland; whether "authentic" songs were sung with or without instrumental accompaniment; and whether the piano, rather than the traditional harp, was a legitimate instrument of accompaniment. Having delineated the historical and theoretical context, Dowling offers a richly detailed analysis of Joyce's story "A Mother." He reveals how almost every element in the story--from the Eire Abu Society to the Antient Concert Rooms, from the conflict between Mrs. Kearney and Hoppy Holohan to the plight of Kathleen Kearney--is charged with meaning by the subtextual conflicts of the revivalists' agenda. Dowling explains also the "authenticity" in Joyce's depiction of vocal performances of "The Lass of Aughrim" in "The Dead" and "The Croppy Boy" in "Sirens," which he calls two "true gems" of authentic Irish music." --Introduction by Charles Rossman and Alan W. Friedman, Guest Editors, pp. 409-410
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In Northern Ireland and Israel schools have long been recognised as key sites for addressing the problems of poor intergroup relations (see Dunn, 1990; Murray, 1985). The developments of integrated schools which welcome members of the main communities have been regarded as a key development which is likely to be instrumental in promoting more harmonious relations. Although the schools have been regarded in the media as a ‘good news story’ the qualitative processes through which teachers within these schools foster reconciliation is not always clear. The purpose of this chapter is thus to explore this question by drawing on contact theory and interviews with teachers in Northern Ireland and Israel.
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Public support for private R&D and innovation is part of most national and regional innovation support regimes. In this article, we estimate the effect of public innovation support on innovation outputs in Ireland and Northern Ireland. Three dimensions of output additionality are considered: extensive additionality, in which public support encourages a larger proportion of the population of firms to innovate; improved product additionality, in which there is an increase in the average importance of incremental innovation; new product additionality, in which there is an increase in the average importance of more radical innovation. Using an instrumental variable approach, our results are generally positive, with public support for innovation having positive, and generally significant, extensive, improved and new product additionality effects. These results hold both for all plants and indigenously owned plants, a specific target of policy in both jurisdictions. The suggestion is that grant aid to firms can be effective in both encouraging firms to initiate new innovation and improve the quality and sophistication of their innovation activity. Our results also emphasize the importance for innovation of in-house R&D, supply-chain linkages, skill levels and capital investment, all of which may be the focus of complementary policy initiatives.
Resumo:
Brass bands are among the most widespread instrumental ensembles in the world, yet there has been little academic interest in them. This is because they stand in a space between art and authenticity, as their repertoires are thought to lack artistic merit while their military legacies have disconnected them from the ‘authentic’ music of ‘the people’. This paper aims to show how it is precisely this intermediary position which has attracted the attention of some (ethno)musicologists, and a growing number of studies demonstrate the analytic potential of this musical universe in a wide range of contexts across the globe.
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This article adopts an ecological view of digital musical interactions, first considering the relationship between performers and digital systems, and then spectators’ perception of these interactions. We provide evidence that the relationships between performers and digital music systems are not necessarily instrumental in the same was as they are with acoustic systems, and nor should they always strive to be. Furthermore, we report results of a study suggesting that spectators may not perceive such interactions in the same way as performances with musical instruments. We present implications for the design of digital musical interactions, suggesting that designers should embrace the reality that digital systems are malleable and dynamic, and may engage performers and spectators in different modalities, sometimes simultaneously.
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RNA polymerase I (Pol I) produces large ribosomal RNAs (rRNAs). In this study, we show that the Rpa49 and Rpa34 Pol I subunits, which do not have counterparts in Pol II and Pol III complexes, are functionally conserved using heterospecific complementation of the human and Schizosaccharomyces pombe orthologues in Saccharomyces cerevisiae. Deletion of RPA49 leads to the disappearance of nucleolar structure, but nucleolar assembly can be restored by decreasing ribosomal gene copy number from 190 to 25. Statistical analysis of Miller spreads in the absence of Rpa49 demonstrates a fourfold decrease in Pol I loading rate per gene and decreased contact between adjacent Pol I complexes. Therefore, the Rpa34 and Rpa49 Pol I–specific subunits are essential for nucleolar assembly and for the high polymerase loading rate associated with frequent contact between adjacent enzymes. Together our data suggest that localized rRNA production results in spatially constrained rRNA production, which is instrumental for nucleolar assembly.