A pesca do atum no Oceano Indico do sudoeste

The tuna species of greatest interest to the countries of the southwest region of Indian Ocean are described. They are called mermas, small "coastal tunas". These fishes need a lot of food and oxygen, but have a limited tolerance for temperature variations. These are features commonly used in determining the possible areas of occurrence and also the most suitable type of fishing gear

Emerging Places of Social Innovation (POSI):: A conceptual framework for social innovation in cities

Social innovation is recurrently positioned as an important collaborative element in helping cities to transition and address human needs and societal challenges to enhance the health, wellbeing, and welfare of citizens. To address a call for more sector-specific research on the spatiality of social innovation, and also further understanding of the process dimension of social innovation, this article presents a conceptual framework of the process of social innovation. By combining social innovation insight from process theories and urban spaces discourse the article indicates that of social innovation in the co-production of space can be grouped into four major processes: 1) Identification of human needs or societal challenges to sustainable development; 2) Development of social relations in systems or structures; 3) Provision of opportunity for social empowerment; 4) Reflection of socio-spatial development practice. Applying this framework, the article examines how productive green infrastructure emerges in the urban landscape as a Place of Social Innovation (POSI)

Marx at the Gold Coast: Reflections on Teaching and the Confrontation with Ideology

This article engages with Marx in Miami and the strategies and pedagogical experiences of teaching Marx and Marxism. It relates the experience of teaching Marxism in a compulsory law course at the Gold Coast, Australia. Marx rarely makes an appearance in law schools and this poses particular challenges when it is taught to politically conservative students. Therefore the article supplies a case for teaching Marx arguing why it is not just appropriate for lawyers but irresponsible to exclude it

Sequence stratigraphy of the Mesozoic Domeyko basin, northern Chile.

The Domeyko basin of northern Chile records Late Triassic-Early Cretaceous mixed carbonate and siliciclastic marine deposition along the western margin of Gondwana. The carbonate and siliciclastic ramp environment is characterised by the deposition of siliciclastic-dominated sediments at times of low accommodation space (lowstand and late highstand systems tracts) and carbonate-dominated sediments during periods of high accommodation space (transgressive and early highstand systems tracts). Along strike variations in siliciclastic sediment supply do not overprint the effects of basinwide changes of relative sea-level. Sequence stratigraphical analysis identifies five second-order sequences resulting from changes in accommodation space and hence, relative sea-level. Within these second-order cycles a higher-frequency cyclicity has also been identified. Each second-order sequence is composed of between 3 and 5 high-frequency sequences which results in a second-order composite sequence, but does not produce the "typical" sequence-sets normally associated with composite sequences. Comparison of the relative sea-level fluctuations interpreted from the Domeyko basin succession with those documented from other similar age South American marginal basins and northern hemisphere basins allows the distinction of regional from global events, and a methodology for potentially differentiating between eustatic and tectonic driving mechanisms. The choice of these basins permits an objective analysis of relative sea-level change using basins of different tectonic setting, on different continental plates. Relative sea-level fall in the late Early Sinemurian, earliest Pliensbachian, earliest Aalenian, Early Callovian, earliest Valanginian, and rises in the earliest Hettangian, earliest and Late Toarcian, Early and Late Bajocian, Late Bathonian and earliest Oxfordian of the Dorneyko basin appear time-equivalent to similar events in other southern and northern hemisphere basins and thus are interpreted to be products of eustatically driven, global sea-level cycles. Relative sea-level falls in the earliest Bathonian, Late Oxfordian, earliest Valanginian and rises in the Late Kimmeridgian are interpreted to be tectonically-driven, continental-scale changes in accommodation space. Although the earliest Valanginian relative sea-level fall can also be seen globally the sequence boundary is interpreted to be tectonically-enhanced by documented regional uplift in Chile and Argentina. The Domeyko basin succession appears to be dominantly controlled by global sea-level fluctuations during the Early-Middle Jurassic, interpreted to have been driven by glacio-eustasy, and by continental-scale fluctuations during the Middle Jurassic to mid-Cretaceous. Mesozoic back-arc basins of western South America record both eustatic and subduction-related relative sea-level fluctuations. To date, the latter have been assumed to be driven chiefly by Pacific plate spreading. However, five tectonically-driven sequence boundaries in the Domeyko and Neuquen basins which have no time correlative expressions in northern hemisphere basins display a close temporal association with five major Gondwanan fragmentation phases. They are: (A) the earliest Bathonian (170 Ma) sequence boundary was driven by the separation of Laurasia and Gondwana; (B) the Late Oxfordian (157 Ma) salinity crisis was driven by the separation of west from east Gondwana; (C) the termination of the marine Domeyko basin was driven by the fragmentation of east Gondwana; CD) the termination of the marine Neuquen Basin (114 Mal was driven by the opening of the South Atlantic; and (E) the major basin inversion associated with the Peruvian tectonic event (100 Mal was driven by the final fragmentation phase within east Gondwana. It is deduced that plate reorganisation associated with the initiation of new oceans during Gondwanan fragmentation resulted in increased coupling along the Andean subduction zone producing regional uplift and thus relative sea-level fall. Responses variously involve: basin barring and Kimmeridgian evaporite production; erosively-based fluvial sandstones directly overlying offshore marine deposits; closure of the Rocas Verdes oceanic marginal basin; sequential termination of marine conditions in the Domeyko and Neuquen back-arc basins; sudden influx of arc-derived alluvial conglomerates resulting from the onset of contractional tectonics; and an incremental jump in the eastward propagation of the Andean volcanic arc. Discrete contractional episodes in the otherwise extensional Andean active margin were thus driven by the incremental spreading phases of the supercontinent. Associated thermal signatures are recorded near the centre of Gondwana by kimberlite emplacement frequency maxima in southern Africa. Plate tectonic theory emphasises the dynamic interaction between adjacent plates, whereby relative rates of motion can be fixed to either the underriding or overriding plate as a reference frame. With reference to the circum-Gondwana subduction zone, I believe that in the past an overemphasis has been placed on the motions of oceanic plates in the Pacific region, while overlooking the role that the thermal evolution of the Pangean supercontinent played in driving circum-Pangean subduction. Thus, careful sequence stratigraphical analysis of active margin sedimentary basins provides a high resolution record, presently under-utilised in detecting, identifying and analysing global tectonic events in time

Discretization Errors and Rotational Symmetry: The Laplacian Operator on Non-Hypercubical Lattices

Discretizations of the Laplacian operator on non-hypercubical lattices are discussed in a systematic approach. It is shown that order $a^2$ errors always exist for discretizations involving only nearest neighbors. Among all lattices with the same density of lattice sites, the hypercubical lattices always have errors smaller than other lattices with the same number of spacetime dimensions. On the other hand, the four dimensional checkerboard lattice (also known as the Celmaster lattice) is the only lattice which is isotropic at order $a^2$. Explicit forms of the discretized Laplacian operators on root lattices are presented, and different ways of eliminating order $a^2$ errors are discussed.Comment: 30 pages in REVTe

Magmatically folded and faulted schlieren zones formed by magma avalanching in the Sonora Pass Intrusive Suite, Sierra Nevada, California

The southwestern margin of the Late Cretaceous Sonora Pass Intrusive Suite, northern Sierra Nevada, California (USA), preserves a densely populated zone of magmatic structures that record dynamic magmatic layer formation and deformation (faulting and folding) within a solidifying upper-crustal magma mush. This zone consists largely of coupled melanocratic (or schlieren) and leucocratic bands hosted within the 95.6 ± 1.5 Ma Kinney Lakes granodiorite (Leopold, 2016), with orientations approximately parallel to the intrusive margin and with inward younging directions. Schlieren consist of a high modal abundance of medium-grained ferromagnesian minerals (hornblende + biotite), zircon, sphene, apatite, opaque minerals, and minor plagioclase and interstitial quartz. Leucocratic bands are dominated by coarse-grained feldspar + quartz with minor ferromagnesian and accessory minerals. Whole-rock geochemical and Sr and Nd isotopic data indicate that the schlieren are derived from the Kinney Lakes granodiorite by effective mechanical separation of mafic minerals and accessory phases. We interpret that the schlieren zone at the margin of the Kinney Lakes granodiorite formed by large-scale collapse of crystal mush by “magma avalanching,” facilitated by gravity, local convection, and possibly by host-rock stoping at the margin. This process eroded a significant portion of the solidifying margin of the chamber and resulted in the formation of magmatically deformed layered structures, which experienced further mingling, re-intrusion, magmatic erosion, and recycling processes. We envisage that magma avalanching of magma mushes in plutons can be achieved by any unstable process (e.g., tectonic, fluid-assisted, stoping, or gravity-driven) in large, longlived magma-mush chambers.Fil: Alasino, Pablo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Ardill, K.. University of Southern California; Estados UnidosFil: Stanback, J.. University of Southern California; Estados UnidosFil: Paterson, Scott Robert. University of Southern California; Estados UnidosFil: Galindo, C.. Universidad Complutense de Madrid; EspañaFil: Leopold, M.. San Juan College; Estados Unidos. School of Science, Math, and Engineering; Estados Unido

Social innovation in urban spaces

Recent international policy advocating for social innovation to be part of strategies to promote sustainable urban development has energised this emerging body of literature. However, there is a need for more sector-specific research to integrate findings on the spatiality of social innovation, co-operative processes, and place-scale relations. This article presents a review (2002–2018) of social innovation in urban spaces. Based on data from 114 publications, the review indicates that research in the spatiality of social innovation can be grouped into three major themes: (1) Spatial planning and community development; (2) Governance; (3) Co-production and service design. The findings suggest that in general the collaboration of end users in place-based development is central to this process of urban change and that process is as significant as the outcome. This article concludes with a research agenda to address identified lacunas

Schlieren bound magmatic structures record crystal flow sorting in dynamic upper crustal magma mush chambers

The size, longevity, and mobility of upper-crustal magma mushes, and thus their ability to mix and interact with newly arriving magma batches, are key factors determining the evolution of magma reservoirs. Magmatic structures in plutons represent local sites of structural and compositional diversity and provide an opportunity to test the extent of physical and chemical processes that operated through time. Regional compilation of compositionally defined magmatic structures, specifically those involving schlieren, in the Tuolumne Intrusive Complex (TIC), yields a synthesis of ∼1500 schlieren-bound structure measurements. Field observations, petrography, and whole-rock geochemistry were integrated to test schlieren formation mechanisms. At a local scale (1 mm–1 m), we find that schlieren-bound structures formed from the surrounding host magma during dynamic magmatic processes such as crystal flow-sorting, magmatic faulting, and folding. Fluidization of the magma mush, interpreted from 1 m to 1 km wide domains of clustered schlieren-bound structures, appears to have operated within a hydrogranular medium, or “crystal slurry” (Bergantz et al., 2017). At the regional scale (10’s km), outward younging patterns of troughs, migrating tubes, and plumes indicate that the mush convected, driven by intrusion of new pulses. Troughs and planar schlieren are weakly oriented parallel to nearby major unit contacts, which could be related to internal mush convection or effects of high thermochemical gradients at internal unit boundaries. We hypothesize that these younging patterns and orientations have the potential to constrain the size of mobile magma mixing regions, that in the TIC extended to a minimum of 150 km2 (∼1500 km3) and were long-lived (>1 m.y). These require the generation of extensive melt-present reservoirs that could flow magmatically, formed from the amalgamation of intruding magma pulses, and precludes dike, sill, or laccolith emplacement models. We conclude that schlieren-bound structures are faithful recorders of the multi-scale, hypersolidus evolution of upper-crustal magma bodies, and represent useful tools for studying plutonic systems.Fil: Ardill, Katie E.. University of Southern California; Estados UnidosFil: Paterson, Scott Robert. University of Southern California; Estados UnidosFil: Stanback, Jonathan. University of Southern California; Estados UnidosFil: Alasino, Pablo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; Argentina. Universidad Nacional de La Rioja; ArgentinaFil: King, James J.. University of Oxford; Reino Unido. University of Durham; Reino UnidoFil: Crosbie, Simon E.. University of Durham; Reino Unid