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This publication, compiled by Gilberto C. Gallopín, Regional Adviser in Environmental Policy for Latin America and the Caribbean, contains the results of the deliberations of the Latin American and Caribbean Regional Workshop on Science and Technology for Sustainable Development. The purpose of the Workshop was to discuss the practical, theoretical and organizational challenges that the quest for sustainable development poses to science and technology (S&T). The increase in complexity and connectivity characteristic of our times results in that the components of the problems are now much less separable than before, and emphasizes the need to approach the problems of development and the environment not only as complex issues in themselves, but also as inseparable and mutually determined. This represents an exceptional challenge to science and technology, particularly to the analytical approaches compartmentalized into disciplines, which represents the bulk of activities and priorities of current S&T systems in both north and south. The Workshop attempted to articulate a Latin American and Caribbean vision towards the search of more effective ways of generating and applying Science and Technology to the problems and opportunities of the region.

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Bats present unique features among mammals with respect to reproduction, and although neotropical bats do not have a hibernation period, many of their reproductive characteristics vary seasonally and interspecifically. Thus, this work aimed to examine the reproductive structures of 18 species belonging to five families of Brazilian bats. The gross anatomy of the testes varied little; however, the epididymis of Emballonuridae and Vespertilionidae showed exceptional structures with a large elongation of the caudal region. We observed a wide variation in the positioning of the testes: Phyllostomidae and Noctilionidae presented external testes; Emballonuridae and Molossidae presented migratory testes that may be in intra-abdominal or external positions; and Vespertilionidae displayed scrotal testes. In the histological evaluation, we observed a different pattern in vespertilionid species, with testicular regression and sperm retention/storage in the cauda epididymis in the five species analyzed. Similar testicular regression was observed in Molossops temminckii; however, sperm retention/storage was not observed in this species. These data suggest that although the species analyzed are tropical species that do not present a prolonged period of torpor (hibernation), they still maintain a period of seminiferous tubule regression and sperm storage very similar to that observed in hibernating bats. © 2012 Wiley Periodicals, Inc.

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Includes bibliography

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Aníbal Pinto Santa Cruz, Director of the Review since 1986, died on 3 January. His death fills us with profound grief and leaves a deep vacuum in this organization. The Economic Commission for Latin America and the Caribbean benefited for many years from the intellectual sparkle and human warmth of Mr. Pinto, who served for several years as Director of the Economic Development Division. What is more, he was one of the personalities who gave the ECLAC secretariat a clear institutional identity. The depth and clarity of his analyses of Chile and its development process were matched by his real dedication to Latin America, which inspired him to make solid and valuable contributions to the progress of ideas in our region. He belonged in his own right to the select group of those thinkers whose new categories and concepts afford others a richer vision of reality. It is not surprising, therefore, that followers and former students of his abound in the region. A person of great intellectual generosity, impatient with conventional wisdom and intolerance from all academic and political quarters, Aníbal Pinto received recognition from the international academic community, as embodied in the Raúl Prebisch Ibero­American Prize in Economics, an honorary doctorate from the University of Campinas, Brazil, and the Chilean National Prize in the Humanities and Social Sciences for 1995. In recent months he received two further distinctions: first, a tribute from his ECLAC colleagues on the occasion of the fiftieth anniversary of the United Nations, and second, a collection of his writings published by the Universidad Nacional Autónoma de México which was presented to him in a ceremony held at the Santiago Book Fair in December 1995. ECLAC has been immensely fortunate in having among its senior officials great personalities who have left behind a legacy of values, principles and key ideas; institution­builders, if you will. If there is anything which distinguishes ECLAC from other United Nations bodies, it is this. Aníbal Pinto's name will undoubtedly be among those which resound the loudest. For this reason, and for his exceptional human qualities, we shall remember him with affection and admiration.

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Includes bibliography

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Includes bibliography

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Single crystalline SnO micro-disks, synthesized by a carbothermal reduction process, exhibited a nearly 1000-fold increase in resistance upon exposure to 100 ppm of NO2 without addition of catalysts or dopants nor the existence of nano-sized dimensions. Moreover, the SnO displayed a greater than 100-fold selectivity to NO2 over potential interferents including CO, H2 and CH4. The high sensor signal and exceptional selectivity for this novel sensor material are attributed to the existence of a high density of active lone pair electrons on the exposed (0 0 1) planes of the single crystalline SnO disks. This, thereby, identifies new means, not utilizing nano-dimensions, to achieve high gas sensitivity. © 2013 Elsevier B.V. All rights reserved.

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A comprehensive biostratinomic study was carried out with abundant stems from the Lower Permian Motuca Formation of the intracratonic Parnaíba Basin, central-north Brazil. The fossils represent a rare tropical to subtropical paleofloristic record in north Gondwana. Tree ferns dominate the assemblages (mainly Tietea, secondarily Psaronius), followed by gymnosperms, sphenophytes, other ferns and rare lycophytes. They are silica-permineralized, commonly reach 4 m length (exceptionally more than 10 m), lie loosely on the ground or are embedded in the original sandstone or siltstone matrix, and attract particular attention because of their frequent parallel attitudes. Many tree fern stems present the original straight cylindrical to slightly conical forms, other are somewhat flattened, and the gymnosperm stems are usually more irregular. Measurements of stem orientations and dimensions were made in three sites approximately aligned in a W-E direction in a distance of 27.3 km at the conservation unit Tocantins Fossil Trees Natural Monument In the eastern site, rose diagrams for 54 stems indicate a relatively narrow azimuthal range to SE. These stems commonly present attached basal bulbous root mantles and thin cylindrical sandstone envelopes, which sometimes hold, almost adjacent to the lateral stem surface, permineralized fern pinnae and other small plant fragments. In the more central site, 82 measured stems are preferentially oriented in the SW-NE direction, the proportion of gymnosperms is higher and cross-stratification sets of sandstones indicate paleocurrents mainly to NE and secondarily to SE. In the western site, most of the 42 measured stems lie in E-W positions. The predominantly sandy succession, where the fossil stems are best represented, evidences a braided fluvial system under semiarid conditions. The low plant diversity, some xeromorphic features and the supposedly almost syndepositional silica impregnation of the plants are coherent with marked dry seasons. Thick mudstones and some coquinites below and above the sandy interval may represent lacustrine facies formed in probably more humid conditions. The taphonomic history of the preserved plants began with exceptional storms that caused fast-flowing high water in channels and far into the floodplains. In the eastern site region, many tree ferns only fell, thus sometimes covering and protecting plant litter and leaves from further fragmentation. Assemblages of the central and western sites suggest that the trees were uprooted and transported in suspension (floating) parallel to the flow. Heavier ends of stems (according to their form or because of attached basal bulbous root mantle or large apical fronds) were oriented to upstream because of inertial forces. During falling water stage, the stems were stranded on riverbanks, usually maintaining the previous transport orientation, and were slightly buried. The perpendicular or oblique positions of some stems may have been caused by interference with other stems or shallow bars. Rare observed stems were apparently waterlogged before the final depositional process and transported as bedload. The differences of interpreted channel orientations between the three sites are expected in a braided fluvial system, considering the very low gradients of the basin and the work scale in the order of tens of kilometers. The mean direction of the drainage probably was to east and the flows apparently became weaker downstream. This study seems to provide reliable data for paleocurrent interpretations, especially considering areas with scarce preserved sedimentary structures. © 2013 Elsevier Ltd.

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Pós-graduação em Geografia - IGCE

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Pós-graduação em Ciências Odontológicas - FOAR

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)