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41.
In north-western Patagonia, obsidian was used during the entire Holocene, and its importance increased with time. Recent fieldwork discovered a new obsidian source located in the Río Grande, which was called ‘Coche Quemado' (CQ). The results indicate that the CQ source has a different geochemical signal than all other sources in the region. Its use is spatially restricted to piedmont and, to a lesser extent, the plains. Chronologically, CQ was exploited in the middle and late Holocene, and its use accounts for a range of spatial distribution between 150 and 200 km.  相似文献   
42.
Particle-induced X-ray emission (PIXE), X-ray diffraction (XRD), electron microprobe analysis (EDS) and scanning electron microscopy (SEM) analytical techniques were used to characterize surface paints in pre- and post-fired Aguada Portezuelo decorated pottery. Surface paintings in black, white, red, brown, burgundy and ochre were analysed. Major, minor and trace elements were detected by PIXE, whereas XRD and SEM-EDS gave information on the main mineral phases and the characteristic morphology for each analysed pigment. The results obtained indicate that the main colour groups can be easily discriminated by PIXE, and they are characterized by only one pigment for each colour: hematite (red) and manganese mineral oxides (black), respectively, whereas white pigments are characterized by calcite, ghelenite and gypsum.  相似文献   
43.
This paper demonstrates the positive effect of immigrant entrepreneurs on manufacturing exports over and above that of diasporas. Using small-scale regional administrative data, our instrumental variable estimates of export gravity models imply that ceteris paribus, that is, holding constant the total number of immigrants, the expected protrade effect of a migrant becoming an entrepreneur amounts to an average increase of US$5,946 in the export flows toward her country of origin. Besides these dyadic effects, immigrant entrepreneurs unlike nonentrepreneurial immigrants raise a region's overall competitiveness and export flows toward other destinations as well.  相似文献   
44.
This article contributes to theorising the often unrecognised continuities between the illegalisation of migrant and refugee mobilities as an effect of lawmaking or other state practices of border policing and immigration law enforcement and the illegalisation of the rights, claims, and juridical status of minoritised citizens. Against a backdrop of resurgent right-wing nationalisms, we pursue this transversal analysis of state practices of illegalisation to draw attention not only to labour subordination and disposability but also the more fundamental relationship between law and terror. The making of such regimes of citizenship takes place in obvious ways at the ostensible outer edges of nation-state territories. They are also replicated in the various spatial arrangements that ensure racialised dispossession within global cities, cities that are better understood as reconfigurations of settler-colonial cities. We argue that the study of practices of illegalisation allows critical poverty scholarship to better discern how sociopolitical categories and classifications that are central to wider processes of marginalisation and domination may arise or be reinforced as effects of the state’s legal productions of illegality.  相似文献   
45.
This paper compares left-wing Latin American populism with Donald Trump. Despite their different social bases and economic policies, they use a similar logic to construct politics as an antagonistic struggle between two camps. Left-wing and right-wing populists aim to rupture existing political institutions to give power to the people, yet they differ in how they construct this category. Whereas Trump used ethnic criteria to differentiate the people from three out groups – Mexicans, Muslims, and African-American militant organisations – left-wing Latin American populists used political and socio-economic criteria. Despite their democratising promises, Latin American populists like Hugo Chávez in Venezuela and Rafael Correa in Ecuador undermined democracy from within. Even though stronger institutions might protect American democracy, Trump has disfigured democracy.  相似文献   
46.
López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [] and Miguel Griffin [], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.  相似文献   

47.
48.
This article studies the particular case of the mythological plays of Calderón that form a cohesive and recognizable set of works in certain circumstances. This kind of comedy is modulated by specific issues of reception, under the dominant global principle of playfulness, through the mechanisms of admiratio, and different strategies of courtly game that can be summarized in four basic areas: conventional comicity, the writing of a theater full of sensorismo, the importance of the intellect games, and finally, the strategies to point identity marks of a particular social group.  相似文献   
49.
Middle Egypt provides a unique insight into the organization of power, politics, economy, and culture at the turn of the third millennium BC. The apparently easy integration of this region into the reunified monarchy of king Mentuhotep II (2055–2004 BC) was possible because the interests and the local lineages of potentates were preserved. Trade and access and/or control of international exchange networks were important sources of wealth and power then. And Middle Egypt appears as a crossroads of diverse populations, as a hub of political and economic power, as a crucial node of exchanges through the Nile Valley, and as a power center whose rulers provided support to the monarchy in exchange of local autonomy and considerable political influence at the Court. In the new conditions of early second millennium, potentates from Middle Egypt succeeded in occupying a unique advantageous position, not matched elsewhere in Egypt, because of the concentration of wealth, trade routes, new technologies, political power, and autonomy in the territories they ruled.  相似文献   
50.
Los Naranjos is one of the most important pre-Columbian human settlements of Honduras related to the south-easternmost border of the Mayan civilization. Although the archaeological site mostly spans from 850 BC to 1250 AD, the present obsidian study was only focused on the Preclassic and Early Classic periods (Jaral, 800–400 BC and Edén, 400 BC–550 AD) where undamaged blades and/or retouched obsidian flakes are rare. In this way, the INAA analyses of 17 obsidian samples, compared with major-trace elements data of Honduran and Guatemalan obsidian sources, are mostly representative of waste flakes. Lithic artifacts of Los Naranjos such as sandstones, basalts, and quartzites come from local geological outcrops; whereas, obsidian provenance has to be searched from sources which are located within a radius up to 300 km far away. San Luis, La Esperanza, and Güinope obsidian sources are located in Honduras while the three most exploited Highland Guatemalan obsidian outcrops, which have been dominating long-distance trade in the Maya area mostly for the Classic-Postclassic periods, are San Martin de Jilotepeque, El Chayal, and Ixtepeque. An Ixtepeque provenance, for all the investigated obsidian samples of Preclassic and Early Classic periods found in the Los Naranjos Archaeological Park, was established, thus emphasizing a long-distance source (180 km). This also confirms that Ixtepeque represents the most important provenance of the obsidian artifacts found in archaeological sites of Western and Central-Western Honduras. The possible role played by some of the most important rivers of Guatemala and Honduras as waterway networks of transport was finally pointed out. New INAA chemical data from the Honduran obsidian source of La Esperanza (“Los Hoyos”, 4 samples) are also reported in this paper.  相似文献   
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