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31.
32.
Brea, M., Zamuner, A.B., Matheos, S.D., Iglesias, A. & Zucol, A.F., December, 2008. Fossil wood of the Mimosoideae from the early Paleocene of Patagonia, Argentina. Alcheringa 32, 427–441. ISSN 0311-5518.

An anatomically preserved mature stem from the Salamanca Formation (early Paleocene) at Palacio de Los Loros, central Patagonia, Argentina, is described and assigned to Paracacioxylon frenguellii sp. nov. The material was preserved by siliceous permineralization and shows features of the secondary xylem typical of subfamily Mimosoideae. This species represents the oldest record of the genus and of the Leguminosae along the western border of Gondwana, and is the world's second oldest record of Leguminosae wood. The species is characterized by ring-porous to semi-ring-porous vessels that are solitary, in multiples of 2–4 and clustered, simple perforation plates, alternate and vestured inter-vessel pitting, homocellular 1–6 seriate rays, tyloses, crystals and diffuse apotracheal, vasicentric paratracheal and confluent axial parenchyma. Paracacioxylon frenguellii has anatomical similarities to Acacia Miller. The presence of Paracacioxylon frenguellii associated with pulvinate leaves suggests that the legumes might have been a component of mesothermal forests developed along the western margin of the Golfo San Jorge Basin during the early Paleocene.  相似文献   
33.
Certain trace elements may accumulate in bone in relation to dietary habits, so some of them are of interest in paleodietary analysis. This is the case with strontium (Sr) and barium (Ba), whose potential value as paleodietary indicators is enhanced by their relatively inert metabolic behaviour. The presence of carious lesions may indicate consumption of sugar and vegetables, whereas the etiology of dental calculus deposition is multifactorial, although some authors consider this as an indicator of protein consumption. Based on these facts we analysed (1) Ba, Sr, and calcium (Ca) content of inner cortical bone obtained from the ramus mandibularis, by atomic absorption spectrophotometry, (2) presence of teeth with carious lesions, and (3) presence of teeth with calculus deposition in 62 mandibles. All samples were obtained from the church La Concepción, an 18th century burial place in Tenerife. Gender was assessed by analysing genetic expression of amelogenin in some cases (14), and by inspection of pelvic bones when available (41 cases). We found (1) Carious lesions in 32 cases, and dental calculus, in 39; no association was observed between sex and presence of dental caries or calculus deposition, nor between the sex and the proportion of carious teeth nor the proportion of teeth with calculus deposition; (2) people buried near the altar (priests and individuals of the highest social class) showed a significantly higher proportion of teeth with dental calculus deposition (χ2 = 5.36, p = 0.021); (3) bone Sr and bone Ba were significantly higher than the values observed in a control group of 10 modern omnivorous individuals; the lowest Sr values were observed among people buried near the altar; and (4) the Ba/Sr ratio was directly related with the proportion of teeth with carious lesions. These data suggest that there were differences in dietary pattern among the individuals belonging to different social classes; overall, consumption of vegetables was widespread, as shown by the high proportion of carious lesions, in relation with raised Ba/Sr ratio, whereas consumption of marine products was scarce.  相似文献   
34.
Few sites with evidence for fire use are known from the Last Interglacial in Europe. Hearth features are rarely preserved, probably as a result of post-depositional processes. The small postglacial basins (<300?m in diameter) that dominate the sedimentary context of the Eemian record in Europe are high-resolution environmental archives often containing charcoal particles. This case study presents the macroscopic charcoal record of the Neumark-Nord 2 basin, Germany, and the correlation of this record with the distinct find levels of the basin margin that also contain thermally altered archaeological material. Increased charcoal quantities are shown to correspond to phases of hominin presence—a pattern that fits best with recurrent anthropogenic fires within the watershed. This research shows the potential of small basin localities in the reconstruction of local fire histories, where clear archaeological features like hearths are missing.  相似文献   
35.
Desalination of rocks used in monuments is a common strategy to reduce the possibility of deterioration by soluble salt crystallization processes. In the last years, some laboratory studies have demonstrated that the application of electrokinetic techniques allow to achieve higher desalination effectiveness, overcoming most limitations of the traditional methods. However, to our knowledge no studies have been conducted on the effectiveness of this technique for in situ desalination of granite. The present study is aimed at filling this gap. The results of an in situ desalination intervention using electrokinetic methods, on a column highly contaminated with salts are presented. The desalination method was optimized to desalinate large in situ structures, trying to establish the necessary protocols (buffering system, irrigation system, setup, etc.) to obtain results as satisfactory as those obtained in laboratory. The results demonstrated the high effectiveness of this method in terms of total salt extraction and depth of salt extraction. The concentration of anions in the column was decreased by more than 80% after 55 days of treatment. No mineralogical and aesthetic damages on the stone were detected after the treatment, confirming the reliability of this method to be applied in situ on granitic rocks.  相似文献   
36.
Alejandro comments on the sense of indeterminacy that pervaded our discussions, notably over what “archaeology” even consists of and over the dilemmas created when the principle of respect for the local community contradicts ethical principles that the archaeologist feels are universal in scale. He tells the story of Carlos Bruch, an early archaeologist in the Catamarca Region, recounting how Bruch portrayed local people and discounted their conceptions of the past, then constructed his own version, contributing to the official version in archaeological discourse. This continues to have ramifications today in the disenfranchisement of local voices in global colonialist projects. Alejandro saw our indeterminancy and quandaries over dilemmas faced by archaeologists as a positive development—a symptom of archaeology changing its pre-theoretical pre-understandings. He emphasizes the importance of local people enacting their own techniques of social memory and their own vocality.  相似文献   
37.
Teen employment is a very important socioeconomic phenomenon because of its consequences on human capital formation. We assess the relation between teen employment and poverty, education, and unemployment in the city of Rosario, using information from the 2010 Argentina Census disaggregated at census block level. We use two different spatial models: The spatial lag model (SLM) and a linear regression model with the spatial component filtered (filtering model, FM). Given the nature of the variables employed, multicollinearity is an issue. One of the techniques proposed in the literature to deal with multicollinearity problems is principal component regression (PCR). We develop an adaptation of such methodology to be used in the SLM. Both models are estimated using their traditional methodologies (instrumental variables for the SLM and OLS for the FM) and using PCR. Although results are similar between the two models, depending on the methodology used in the estimations they differ greatly. Under traditional methodologies estimations show high variability, instability, and contradictory outcomes, but under PCR, results behave according to the literature.  相似文献   
38.
Filippini, F.S., Otero, A. & Gasparini, Z., June 2016. The phylogenetic relevance of the sacrum among macronarian sauropods: insights from a pelvis from the Upper Cretaceous of Patagonia, Argentina. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Anatomical variation in the sacrum is useful for differentiating sauropod lineages. Morphological variation in the sacrum has been underestimated mainly because of its anatomical complexity and uncertain homologies with presacral and postsacral elements. We describe a titanosaurian sauropod pelvis (MLP 46-VIII-21-2) from Plottier (Neuquén Province, Argentina) collected in the 1940s from Coniacian–Santonian (Upper Cretaceous) strata. The degree of bone fusion in the specimen (fused vertebral centra forming a single rod, with neural arches fused to the corresponding centrum and to adjacent neural arches) indicates a late ontogenetic age. The presence of a space between the first vertebra and the anterior margin of the illium, together with a scar located on the anterior part of the preactabular process, suggest the possible presence of a sixth sacral vertebra (putative dorsosacral additional characters present in the ilium point towards affinities with Titanosauria. The completeness and good preservation of the specimen allowed us to track features along the sacral series and to compare characters with other sauropods. Within a phylogenetic context, and based on the pattern present in basal sauropodomorphs, the presence of three sacral elements attached to the rim of the acetabulum in eusauropods opens the possibility for considering such elements as primordial sacrals.

Florencia S. Filippini [], División Paleontología de Vertebrados, Museo de La Plata, Paseo del Bosque s/n, La Plata, 1900, Bs. As., Argentina; Alejandro Otero []; Zulma Gasparini [] CONICET—División Paleontología de Vertebrados, Museo de La Plata, Paseo del Bosque s/n, La Plata, 1900, Bs. As., Argentina.  相似文献   

39.
ABSTRACT

This article explores the propagation of national narratives through football in both the Spanish and the European media in the period 2008–2012. The Spanish national team's victories in the 2008 and 2012 Euros and the 2010 World Cup resulted in the consolidation of a domestic “narrative of success” that depicted Spain as a flourishing, modern European country. Yet as the economic crisis increased, Spanish governments, mass media, and corporations promoted this narrative of success as a “compensation mechanism,” aiming at making up for the country's dire financial situation. In the European media, the initially benign portrait of Spaniards was gradually transformed into a new representation that depicted Iberians as slackers and scroungers of European Union funds. The article shows the re-emergence of derogatory stereotypes as a manner of making Spaniards scapegoats for the economic crisis, while reinforcing nationalist narratives among Europeans.  相似文献   
40.
Alternative food networks face both challenges and opportunities in rethinking the role of precarious employment in food system transformation. We explore how alternative food networks in British Columbia, Canada have engaged with flexible and precarious work regimes for farmworkers, including both temporary migrant workers and un(der)paid agricultural interns. Based on in‐depth interviews, participant observation and document analysis, we find that alternative food actors often normalize a precarious work regime using a moral economy frame. This framing describes precarious farm employment as either a necessary challenge in the transition to sustainability, or merely involving a few individual “bad apple” farmers. Further, this framing involves an aversion to “one‐size‐fits‐all” regulation by the state in favor of consumer‐driven regulation of labor standards. Our analysis suggests that a moral economy framing can obscure systemic inequities in precarious farm employment and dampen the impetus for structural change through collective food movement organizing.  相似文献   
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