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241.
Meghan E. Gray Christian Wolf Marco Barden Chien Y. Peng Boris Häußler Eric F. Bell Daniel H. McIntosh Yicheng Guo John A. R. Caldwell David Bacon Michael Balogh Fabio D. Barazza Asmus Böhm Catherine Heymans Knud Jahnke Shardha Jogee Eelco van Kampen Kyle Lane Klaus Meisenheimer Sebastian F. Sánchez y Taylor Lutz Wisotzki Xianzhong Zheng David A. Green R. J. Beswick D. J. Saikia Rachel Gilmour Benjamin D. Johnson Casey Papovich 《Monthly notices of the Royal Astronomical Society》2009,393(4):1275-1301
We present an overview of the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). STAGES is a multiwavelength project designed to probe physical drivers of galaxy evolution across a wide range of environments and luminosity. A complex multicluster system at z ∼ 0.165 has been the subject of an 80-orbit F606W Hubble Space Telescope (HST) /Advanced Camera for Surveys (ACS) mosaic covering the full span of the supercluster. Extensive multiwavelength observations with XMM–Newton , GALEX, Spitzer , 2dF, Giant Metrewave Radio Telescope and the 17-band COMBO-17 photometric redshift survey complement the HST imaging. Our survey goals include simultaneously linking galaxy morphology with other observables such as age, star formation rate, nuclear activity and stellar mass. In addition, with the multiwavelength data set and new high-resolution mass maps from gravitational lensing, we are able to disentangle the large-scale structure of the system. By examining all aspects of an environment we will be able to evaluate the relative importance of the dark matter haloes, the local galaxy density and the hot X-ray gas in driving galaxy transformation. This paper describes the HST imaging, data reduction and creation of a master catalogue. We perform the Sérsic fitting on the HST images and conduct associated simulations to quantify completeness. In addition, we present the COMBO-17 photometric redshift catalogue and estimates of stellar masses and star formation rates for this field. We define galaxy and cluster sample selection criteria, which will be the basis for forthcoming science analyses, and present a compilation of notable objects in the field. Finally, we describe the further multiwavelength observations and announce public access to the data and catalogues. 相似文献
242.
Fabio Orlandi Carlo Sgromo Tommaso Bonofiglio Luigia Ruga Bruno Romano Marco Fornaciari 《Theoretical and Applied Climatology》2009,97(3-4):339-347
Phenological observations of the anthesic phases of olive flowering in a central Mediterranean area were recorded over a 9-year period. The aim of this research was to compare the flowering dates in relationship to the meteorological changes. Pollen emission from anthers was monitored by remote instrumentation placed directly in olive groves and phenological data regarding daily pollen concentrations (pollen/m3) were recorded using a pollen monitoring methodology. The rhythm of the phenological phases emerged as dependent on the meteorological trend of the spring forcing temperature. Generally, the phenomenon of pollen emission occurred progressively earlier prior to 2001, while in the following 5 years, the trend seemed to be inverted, showing a progressive delay of flowering. The spring quarterly mean temperature trends registered by GISS data in Europe confirmed the presence of diverse meteorological behavior during the study period, probably causing the biological divergences that were monitored. The principal result of the present contribution is to evidence the relativity of empirical investigations and observations considering different time intervals. This is due to the partial, brief series (9 years) of flowering dates which have to be considered as part of a longer series (26 years) in order to have a complete vision of the true phenomenon. 相似文献
243.
244.
Marco Antonsich 《GeoJournal》2010,75(1):119-132
Although geographers have largely investigated the notion of place, the relationship between place and Self does not seem
to have received a similar attention, both theoretically and empirically. After the initial interest expressed by humanistic
geographers, social constructivism and cultural materialism (two dominant paradigms in use since at least the 1980s) have
somewhat moved the interest towards a sort of social(izing) discourse, which has pushed the individual dimension to the margin.
Accordingly, this dimension has been treated as a mere product of social discourses, as purely embodying and (re)enacting
certain social categories (gender, sex, race, etc.) or, again, it has been discredited as psychologically ‘mentalistic’ and
geographically ‘trivial’. In the present article, I aim to rescue this personal, intimate dimension and show how, beyond an
all-encompassing social(izing) logic, it remains at work in the ways people relate to place. Theoretically, the study builds
on the early contributions of humanistic geography, complemented with more recent works in environmental and social psychology.
Empirically, it is grounded in narratives of place collected during interviews and focus groups administered in four regional
case studies in Western Europe. The article advances and illustrates, with empirical materials, a simple theoretical framework,
which aims to contribute to the understanding of how meanings of place implicate and are implicated in the construction of
the Self. 相似文献
245.
Transpressional tectonics and nappe stacking along the Southern Variscan Front of Morocco 总被引:1,自引:0,他引:1
Andrea Cerrina Feroni Alessandro Ellero Marco G. Malusà Giovanni Musumeci Giuseppe Ottria Riccardo Polino Leonardo Leoni 《International Journal of Earth Sciences》2010,99(5):1111-1122
The Southern Variscan Front in the Tinerhir area involves Palaeozoic allochthonous units (Ouaklim and Tilouine units) thrust
onto the northern edge of the West African Craton during late Carboniferous time. Illite crystallinity data highlight an anchizonal
grade for the Ouaklim Unit, and a diagenesis-anchizone transition for the Tilouine Unit during deformation phase D1. The tectonic
stack is crosscut by major dextral reverse faults bounding E–W trending domains of dominant shortening deformation (central
domain) and strike-slip deformation (northern and southern domains), later segmented by a network of post-Variscan faults.
This complex deformation pattern is the result of kinematic partitioning of dextral transpression along the Southern Variscan
Front, coeval with the Neovariscan (300–290 Ma) oblique convergence observed at the scale of the whole Moroccan Variscides.
Partitioning of dextral transpression described in the Tinerhir area is consistent with dextral wrench faulting along the
Tizi n’ Test Fault, and with Appalachian-style south-directed thrusting in the Tinerhir and Bechar-Bou Arfa areas. 相似文献
246.
Eva Pacioni Marco Petitta Ezio Burri Maria Fanelli Piero Mazzeo Fabrizio Ruggieri 《Environmental Earth Sciences》2010,61(1):201-216
This paper analyses flow and transport of pesticides from the unsaturated zone to groundwater so as to predict concentration
of those contaminants in the Fucino Plain’s groundwater, by site investigations and numerical simulations. Pesticides were
detected in surface water (peaks of 13 μg L−1) and groundwater (peaks of 0.37 μg L−1). Modelling tools made it possible to identify that pattern of precipitation, organic matter content, and root thickness
are the key factors involved in vertical seepage of pesticides. Numerical simulations indicated that a significant fraction
of contaminants is leached from the most surficial soil layers through runoff, while only a secondary fraction is mobilised
towards groundwater. Likelihood of contaminating deep groundwater is fairly low, whereas surface waters show higher susceptibility.
Results of the proposed conceptual hydrogeological model show that pesticides are more likely to be entrained by mixing of
stream water with shallow groundwater in periods of high water exploitation from shallow wells. 相似文献
247.
Cristina M. Belfiore Mauro F. La Russa Paolo Mazzoleni Antonino Pezzino Marco Viccaro 《Environmental Earth Sciences》2010,61(5):995-1003
This paper presents new petro-chemical data on some typical mortars found in many buildings in the historic city centre of Catania (Eastern Sicily). Extensively used in the architecture of the city from the second half of the nineteenth century until the mid-twentieth century, these mortars are characterised by a particular aggregate locally known as “agghiara” or “ghiara”. This is the product of thermal transformation induced by the heating undergone by palaeo-soils, originally rich in organic matter, covered by lava flows, which change their colour to reddish nuances. The volcanic origin of ghiara is a peculiar feature of the Etnean area. Mixed with lime, it gives to mortars an intense reddish colour, as well as hydraulic properties, which are comparable with those of the historically used pozzolana. This work aimed at complete characterisation of these ghiara mortars, for providing information on several important technological aspects. In order to get information on used raw materials, sampling of some ancient underground quarries, located both in the historic city centre and at the periphery, was also performed. Results led to the complete characterisation of the selected ghiara mortars and yielded information on some technological features and the composition of both newly formed and secondary phases, these latter due to alteration processes. The hydraulic properties of mortars have been related to the occurrence of amorphous phases within the ghiara aggregate, which were identified by means of SEM morphological observations. These phases, formed during the “firing” process of palaeo-soils, react with lime producing hydraulic compounds (C–S–H and C–A–H), which are responsible for the mortars durability. 相似文献
248.
Andrea Cannata Gaetano Giudice Sergio Gurrieri Placido Montalto Salvatore Alparone Giuseppe Di Grazia Rocco Favara Stefano Gresta Marco Liuzzo 《Environmental Earth Sciences》2010,61(3):477-489
Large variations of the CO2 flux through the soil were observed between November 2002 and January 2006 at Mt. Etna volcano. In many cases, the CO2 flux was strongly influenced by changes in air temperature and atmospheric pressure. A new filtering method was then developed
to remove the atmospheric influences on soil CO2 flux and, at the same time, to highlight the variations strictly related to volcanic activity. Successively, the CO2 corrected data were quantitatively compared with the spectral amplitude of the volcanic tremor by cross correlation function,
cross-wavelet spectrum and wavelet coherence. These analyses suggested that the soil CO2 flux variations preceded those of volcanic tremor by about 50 days. Given that volcanic tremor is linked to the shallow (a
few kilometer) magma dynamics and soil CO2 flux related to the deeper (~12 km b.s.l.) magma dynamics, the “delayed similarity” between the CO2 flux and the volcanic tremor amplitude was used to assess the average speed in the magma uprising into the crust, as about
170–260 m per day. Finally, the large amount of CO2 released before the onset of the 2004–2005 eruption indicated a deep ingression of new magma, which might have triggered
such an eruption. 相似文献
249.
Simone Bregaglio Marcello Donatelli Roberto Confalonieri Marco Acutis Simone Orlandini 《Theoretical and Applied Climatology》2010,102(3-4):429-438
The availability of hourly air relative humidity (HARH) data is a key requirement for the estimation of epidemic dynamics of plant fungal pathogens, in particular for the simulation of both the germination of the spores and the infection process. Most of the existing epidemic forecasting models require these data as input directly or indirectly, in the latter case for the estimation of leaf wetness duration. In many cases, HARH must be generated because it is not available in historical series and when there is the need to simulate epidemics either on a wide scale or with different climate scenarios. Thirteen modelling solutions (MS) for the generation of this variable were evaluated, with different input requirements and alternative approaches, on a large dataset including several sites and years. A composite indicator was developed using fuzzy logic to compare and to evaluate the performances of the models. The indicator consists of four modules: Accuracy, Correlation, Pattern and Robustness. Results showed that when available, daily maximum and minimum air relative humidity data substantially improved the estimation of HARH. When such data are not available, the choice of the MS is crucial, given the difference in predicting skills obtained during the analysis, which allowed a clear detection of the best performing MS. This study represents the first step of the creation of a robust modelling chain coupling the MS for the generation of HARH and disease forecasting models, including the systematic validation of each step of the simulation. 相似文献
250.
Thomas Higham Fiona Brock Marco Peresani Alberto Broglio Rachel Wood Katerina Douka 《Quaternary Science Reviews》2009,28(13-14):1257-1267
Radiocarbon dating of material from Late Pleistocene archaeological sites is challenging. Small amounts of modern 14C-labelled contamination will significantly affect the reliability of dates from the period, producing erroneous results. Recent developments in sample pre-treatment chemistry have shown that problems in reliable age determination during this period are surmountable. In this paper we provide an example of one such case, from the Middle to Upper Palaeolithic transitional site of the Grotta di Fumane, in northern Italy. We AMS dated two fractions of the same charcoal samples derived from a series of superimposed Mousterian, Aurignacian and Gravettian levels excavated at the site. One fraction was treated using the routine acid–base–acid (ABA) method, the other with the more rigorous acid–base-oxidation/stepped combustion (ABOx–SC) method. The latter method produced consistently older, and almost certainly more reliable, results. The eruption of the known-age Campanian Ignimbrite from the Phlegrean Fields near present-day Naples at 39.3 ka yr BP seals Ulluzzian and Proto Aurignacian levels in the south of Italy. Equivalent cultural levels are present at Fumane and the results obtained with the ABOx–SC methods are consistent with the ages inferred for sites in the south of Italy based on the presence of the Campanian Ignimbrite. New results from a sample found beneath the Campanian Ignimbrite at the Russian site of Kostenki, obtained using both the ABA and ABOx–SC, methods are also presented. They support the conclusion reached at Fumane by demonstrating that, in many cases, the ABOX–SC treatment effectively removes contamination where the ABA treatment does not. The results of the work offer a sobering examination of the problems inherent in the current radiocarbon database relating to the period, and highlight the dangers of an uncritical use of the corpus of 14C results obtained over the last few decades. Based on our results, we predict that more than 70% of the 53 previously available determinations from Fumane are erroneously young. A way forward is suggested, using these improved chemical preparation methods, applying analytical methods to characterise the material dated, and testing existing site chronologies to establish which previous determinations are liable to be inaccurate. 相似文献