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31.
    
ABSTRACT Understanding the impact of road investments on deforestation is part of a complete evaluation of the expansion of infrastructure for development. We find evidence of spatial spillovers from roads in the Brazilian Amazon: deforestation rises in the census tracts that lack roads but are in the same county as and within 100 km of a tract with a new paved or unpaved road. At greater distances from the new roads the evidence is mixed, including negative coefficients of inconsistent significance between 100 and 300 km, and if anything, higher neighbor deforestation at distances over 300 km.  相似文献   
32.
    
The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.  相似文献   
33.
    
Abstract

Multiple sclerosis (MS) was first presented in a clinical setting in 1838. In this paper the presentation and treatment of a transient hemiparesis in a drummer in 1789 is discussed. This may have been an early case of MS and presents evidence against the theory that MS is an infectious disease beginning in the 19th century.  相似文献   
34.
    
Over one hundred years of palaeontological research in northwestern Argentina has provided extensive knowledge of Andean lower Palaeozoic fossil assemblages, with trilobites, graptolites, brachiopods and echinoderms being among the most prominent groups. This record is enriched by the recent discovery of soft-bodied worms in Cambrian outcrops of northwestern Argentina. Palaeoscolex sp. cf. P. ratcliffei from the Furongian Lampazar Formation in Jujuy is described, considerably expanding the biogeographical range of this genus and filling the distributional gap, between the well-known early–middle Cambrian occurrences of Palaeoscolex and those of its Ordovician species.  相似文献   
35.
Cultural policy research exists in many contexts, asks many different kinds of questions and adopts a wide repertoire of research methodologies from a raft of academic discourses. This article investigates the research questions and approaches being undertaken by those working in this field. In order to achieve this, the article draws upon readings of contemporary publications in the field and on the authors’ experiences of building a research capacity in the area of cultural policy in a British – and, more particularly, a post‐devolution Scottish – university. The article traces the emergence of an academic discipline in the field, and seeks to advance this by reviewing a tripartite research agenda investigating: the history and historiography of cultural policy; the principles and strategies of cultural policy; and, the relationships between cultural policy and cultural theory/cultural studies.  相似文献   
36.
    
This article analyzes the mechanisms through which metropolitan governance is established in Montreal's aeronautics sector, one of the most important and innovative industries in the region. The article also examines the role of lead firms, socio‐economic actors, and public agencies from a territorial point of view. It is established that on the one hand the existence of a small number of prime producers at the local level facilitates productive linkages among businesses through subcontracting, and on the other hand, the intensive participation of intermediate socio‐economic agencies and organizations ensures a metropolitan anchoring of the sector and creates a strong territorial identity among the players.  相似文献   
37.
苏晓智  白娟 《人文地理》2013,28(4):58-63
在当代世界各国的城市化进程中,城市的更新改造和发展以及相关问题和矛盾的解决都是要面临的重要课题。示范城市运动是美国大规模城市更新运动的重要阶段,也是轰轰烈烈的\"伟大社会\"改革中后期重要的战略转移。本文选取该项运动为研究主题,回顾了其发生背景、发展过程,分析了其正反两方面的经验,以期为中国在进入改革开放关键时期构建和谐社会进程中更好地解决城市问题提供一个有价值的参照。  相似文献   
38.
This article examines how the Spanish Crown's attempt to implement a systematic linguistic policy across the New World from the last quarter of the sixteenth century failed in the New Kingdom of Granada. Based on the ambiguous and problematic idea of ‘general languages’ that had arisen in Mexico and Peru, this one-size-fits-all policy was wholly unsuited to even the Muisca heartlands of the archdiocese of Santa Fe. Instead, local authorities settled on the use of bespoke translations of catechetical and pastoral texts into individual local languages, even at parish level, thereby reinforcing linguistic particularism—but availing themselves of the disciplinary and procedural framework of the legislation to support their strategy. In doing so, the article seeks to challenge established assumptions about the treatment of indigenous languages in New Granada in this period, and to throw new light on unanswered questions about the Spanish response to the region's linguistic heterogeneity.  相似文献   
39.
Portus Ilicitanus (Picola, Alicante) was the main sea harbour of the Roman Colonia Iulia Ilici Augusta and as such played a crucial role in the supply of fundamental commodities to the Iberian Peninsula. Excavations yielded large quantities of glass in fourth‐ and early fifth‐century contexts. Elemental analysis of 60 samples by laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) confirmed that the glasses were imported from the Eastern Mediterranean. A majority of the glasses correspond to the HIMTa primary production group, which originates from Egypt. The statistical evaluation of published data of 589 HIMT glasses further revealed differential distribution patterns of the HIMTa and HIMTb subtypes between the Eastern and Western Mediterranean, suggesting chronological trends that are linked to wider geopolitical changes. This demonstrates the need for systematic large‐scale approaches to identify supply patterns and possible factors underlying geographical differences and/or chronological developments.  相似文献   
40.
ABSTRACT

The “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given.  相似文献   
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