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71.
This article describes the important discovery of a Late Bronze Age gold torc that was unearthed in a field of Acehúche (Cáceres, Spain). It was buried underneath some rocks at a site near a river crossing over the Tagus river. In its immediate vicinity, archaeological remains dating from the Copper Age to the Late Bronze Age have been found, which indicates the long use of this crossing. Until recently here, there existed a ferry and a chapel; and the place went by the toponym of the Dehesa de San Cristóbal. Legend too has it that the water from the river had curative properties. All of these components have maintained the sacred nature of the spot, otherwise transformed over the course of time, and reflect an earlier sacred landscape with quite ancient roots.  相似文献   
72.
We report a successful extraction and sequencing of ancient DNA from carbonized rice grains (Oryza sativa) from six archaeological sites, including two from India and four from Thailand, ranging in age from ca. 2500 to 1500 BP. In total, 221 archaeological grains were processed by PCR amplification and primary-targeted fragments were sequenced for comparison with modern sequences generated from 112 modern rice populations, including crop and wild varieties. Our results include the genetic sequences from both the chloroplast and the nuclear genomes, based on four markers from the chloroplast and six from the nuclear genome. These markers allow differentiation of indica rice from japonica rice, the two major subspecies of Asian rice (O. sativa) considered to have separate geographical origins. One nuclear marker differentiates tropical and temperate forms of subspecies japonica. Other markers relate to phenotypic variation selected for under domestication, such as non-shattering, grain stickiness (waxy starch) and pericarp colour. Recovery and identification of sequences from nuclear markers was generally poor, whereas recovery of chloroplast sequences was successful, with at least one of four markers recovered in 61 % of archaeological grains. This allowed for successful differentiation of indica or japonica subspecies variety, with japonica identified in all the Thai material and a mixture of indica and japonica chloroplasts in the two Indian assemblages. Rice subspecies was also assessed through conventional archaeobotanical methods relying on grain metrics, based on measurements from 13 modern populations and 499 archaeological grains. Grain metrics also suggest a predominance of japonica-type grains in the Southeast Asian sites and a mixture of japonica and indica in the Indian sites with indica in the minority. The similar results of grain metrics and ancient DNA (aDNA) affirm that grain measurements have some degree of reliability in rice subspecies identification. The study also highlights the great potential of ancient DNA recovery from archaeological rice. The data generated in the present study adds support to the model of rice evolution that includes hybridization between japonica and proto-indica.  相似文献   
73.
Salt crystallization is a major cause of degradation in old buildings. One of the issues that stills need clarification is regarding the influence of the salts on the capillary absorption and subsequent drying of porous building materials. This article presents an experimental study that included capillary absorption and evaporative drying tests on two types of material (lime mortar and ceramic brick) using pure water or saturated solutions of six salts (sodium chloride, sodium sulfate, sodium nitrate, sodium carbonate, potassium nitrate, or potassium carbonate). The results of capillary absorption agree only roughly with the linear relationship, predicted by theory, between sorptivity and the square root of the ratio between viscosity η and surface tension σ of the solution (σ/η)1/2. This poor agreement is probably due to material heterogeneity. The drying dynamics was regular and showed little dispersion between specimens, but only for the uncontaminated materials. Indeed, the drying dynamics of the salt contaminated materials was often irregular or diverged among similar specimens, and the same happened with their salt decay patterns. The main conclusion is that soluble salts can amplify the effects on drying of the small structural heterogeneities that porous building materials normally depict.  相似文献   
74.
Sagasti, A.J., García Massini, J., Escapa, I.H., Guido, D.M. & Channing, A., August 2016. Millerocaulis zamunerae sp. nov. (Osmundaceae) from Jurassic geothermally influenced wetland environments of Patagonia, Argentina. Alcheringa 40, xxx–xxx. ISSN 0311-5518

A new species of Millerocaulis Erasmus ex. Tidwell emend. Vera is defined based on several permineralized stems recovered from geothermally influenced chert deposits in the Middle–Late Jurassic La Matilde Formation (Santa Cruz, Argentina). Millerocaulis zamunerae sp. nov. is characterized by the presence of an ectophloic dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, homogeneous sclerotic ring in the petiole bases, two masses of sclerenchyma lining the concavity of the petiolar vascular bundle, petiolar inner cortex with sclerenchyma strands in the outermost petiole cycles and stipular wings having one large and several smaller sclerenchyma bundles. Millerocaulis zamunerae inhabited geothermal wetlands and other hot-spring-related sedimentary facies associated with the La Bajada epithermal deposit. Reference to active geothermal wetlands, analogous living plants and other fossil hot spring ecosystems suggest the plant’s tolerance of physico-chemical stressors including elevated temperature, pH, salinity and phytotoxic metals/metalloids. Millerocaulis zamunerae thrived in wetlands preserved in the Jurassic geothermal systems of Santa Cruz Province, the same kind of environment in which Equisetum thermale Channing et al. was recorded previously.

Ana Julia Sagasti [] División Paleobotánica, Facultad de Ciencias Naturales y Museo. Becaria Doctoral Consejo Nacional de Investigaciones Científicas y Técnicas, Paseo del Bosque S/N B1900FWA La Plata, Buenos Aires, Argentina. Juan García Massini [] Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET. Entre Ríos y Mendoza S/N, 5301 Anillaco, La Rioja Argentina. Ignacio H. Escapa [] Museo Paleontológico Egidio Feruglio, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Fontana 140, U9100GYO, Trelew, Chubut, Argentina. Diego M. Guido [] Instituto de Recursos Minerales (INREMI), Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Consejo Nacional de Investigaciones Científicas y Técnicas. Calle 64 y 120, La Plata (1900), Argentina. Alan Channing [] School of Earth & Ocean Sciences, Cardiff University, Cardiff CF10 3AT, UK.  相似文献   
75.
High-tech development has been broadly accepted as a prominent matter of regional development policies and plans at the global level. Strategies to enhance it have evident implications for spatial planning policies, plans and visions. Consequently, careful attention should be paid to the role that spatial planning policies play in the national and regional efforts to advance high-tech development in a particular place. This study addresses the relationship between the spatial planning system and high-tech development, searching to explain the spatial implications resulting from this relationship. It approaches the topic by comparing high-tech development experiences in the Netherlands and Taiwan from an institutional perspective. Although both countries have used a range of spatial strategies for economic growth through high-tech development, the results show that their different institutional settings, power relations between different levels of government and conceptions of science park have led to the implementation of two very distinct spatial strategies, shaping different spatial patterns of high-tech development clustering in these two regions. The findings demonstrate the potential of the institutional approach to study international planning issues, and contribute to theories of high-tech development and spatial planning.  相似文献   
76.
Scholarly literature on interpersonal relationships between tourist women and local men has been largely discussed under the heteronormative framework of love and sexuality. However, the plenitude of ways in which these intimacies manifest themselves requires that we pay attention to the manifold forms of heterosexual relatedness that these intimacies generate. This article considers how intimate liaisons between Western women and Balinese men that commenced as holiday romances in Bali transform into unruly relationality and transnational motherhood. Focusing the analysis on women's narratives, the article explores how subjects engage in the production of sexual, reproductive, social and economic forms of transnational relatedness wherein the mother and child live permanently in the women's country of citizenship while the Balinese father remains in Bali. Rather than aspiring towards a monogamous relationship and cohabitation as heteronormativity prescribes, the article demonstrates how these non-conventional, transnational families perpetually challenge the nuclear family norm, boundaries of normative motherhood and dichotomies of home versus away.  相似文献   
77.
78.
International mobility has become a key requirement in science and technology (S&T) professional career progression. On the one hand, the increasing mobility of women suggests that this may be a way for them to avoid or get away from women-unfriendly working environments. On the other hand, international mobility can present problems for women as they, particularly, have to plan their lives around their professional goals and personal lives. This article addresses the international mobility strategies of women regarding their personal and professional choices. We analyse their motivations to move, the way they manage their lives abroad and the effects of mobility on their lives. The analysis is based on 24 in-depth interviews of highly skilled women working in Spanish S&T sectors. Our main findings show that mobility is a new challenge which may improve women's family lives and professional careers. However, they have to plan carefully their lives on a long-term as well as a daily basis. In this sense, they need strong personal determination and the ability to balance their professional and personal goals. Moreover, their personal decisions depend not only on them as individuals, but also on their partners and families, on wider social values, on the institutional support they enjoy, and on the general public policies which they are affected by.  相似文献   
79.
Social mobilizations that are devoted to contesting development and creating alternative economic arrangements conducive to the pursuit of a dignified life have recently sprung up. Not only do they criticize the current state of affairs but they actively seek and experience new ways of living, inspired by what Bloch calls the anticipatory consciousness of the ‘not‐yet‐become’, that is, another reality not yet materialized but which can be already experienced. This article argues that these mobilizations are not adequately captured by the term ‘social movements’. The uniqueness of these mobilizations requires a conceptual and epistemological turn that is able to accommodate the post‐development critique of development as well as their emancipatory dimension. We propose to name them ‘hope movements’ to account for the collective action directed to anticipate, imperfectly, alternative realities that arise from the openness of the present one. We conclude by discussing the political relevance of hope movements for the pursuit of the good life as an alternative to development.  相似文献   
80.
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