Revistas Universidad del Bío-Bío
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Circuitos de la economía urbana y patrimonio-territorial Latinoameriano. Mercado de Xochimilco, Ciudad de México
Get PDFTraditional markets in Latin American metropolises may mitigate the risks of urbanization-commercialization in historical sites and mediate rural-city and ancestral-contemporary interactions. Considering that the Xochimilco Market (Mexico City) generates centripetal-centrifugal forces which activate the local economy (formal and informal), the goal of the article is to analyze the indissolubility of its neighboring internal and external trade spaces (producer zones, informal trade, chinampas), creating a territory of supply, labor, and subsistence of the impoverished population. A mixed methodological design is adopted, with participant observation, semi-structured interviews, and qualitative spatial analysis. The decolonial concept of " territorial heritage" and the theory of "circuits of urban economy" applied to the Global South helps verify the socio-spatial experiences and permanence that, from the market, subjects and families have maintained, in a scenario of selective modernization of metropolitan territories and growth of informality onto the continent.Los mercados tradicionales en las metrópolis latinoamericanas pueden mitigar riesgos derivados de la urbanización y la comercialización en sitios históricos y pactar las interacciones campo-ciudad y ancestralidad-contemporaneidad. Considerando que el Mercado Xochimilco (Ciudad de México) genera fuerzas centrípetas y centrífugas activadoras de la economía local (formal e informal), el objetivo del artículo es analizar la indisolubilidad de sus espacios de comercio interior y exterior aledaño (zonas de productores, de chinampas y ambulantaje), constitutivos de un territorio de abasto, labor y supervivencia de la población empobrecida. Se adopta un diseño metodológico mixto, con observación participante, entrevistas semiestructuradas, codificación y análisis espacial cualitativo. El concepto decolonial “patrimonio-territorial” y la teoría de los “circuitos de la economía urbana” aplicada al Sur Global permiten comprobar las experiencias socioespaciales y permanencias que, desde el mercado, han mantenido sujetos y familias, en un escenario de modernización selectiva de los territorios metropolitanos y aumento de la informalidad en el continente
Placas aislantes de EPS reciclado: factores críticos y potencialidades para la viabilidad productiva de un emprendimiento en el Partido de La Plata
Get PDFPrevious research has allowed developing and characterizing an expanded polystyrene waste (EPS) based insulation material that can be used to manufacture plates, providing job opportunities to unemployed or vulnerable social groups. By working together with a local recycling cooperative, the production processes needed for their manufacture on a scale suitable for commercialization were determined. The goal of this research is to analyze these production processes and identify the critical aspects that make the technology’s implementation and management viable. The methodology used involves i. the product’s adaptation; ii. determining supplies and resources for its feasibility; iii. detecting the most critical production processes; and, iv. adapting to the particular case of application. A set of minimum requirements is obtained to develop a productive venture. In addition, the most critical processes related to the separation and obtaining of the EPS and its continuous supply over time, are identified. The results summarize contributions to replicate and make this experience sustainable.Investigaciones previas han permitido desarrollar y caracterizar un material aislante a partir de descartes de poliestireno expandido (EPS) que puede utilizarse para la fabricación de placas, brindando oportunidades laborales a grupos sociales desocupados o vulnerables. Trabajando en articulación con una cooperativa de recicladores local, se determinaron los procesos productivos necesarios para su fabricación en una escala apta para su comercialización. El objetivo de esta investigación es analizar estos procesos productivos e identificar los aspectos críticos para la viabilidad de ejecución y gestión de esta tecnología. La metodología utilizada implica: i. la adecuación del producto; ii. la determinación de los insumos y recursos para su viabilidad; iii. la detección de los procesos productivos con mayor criticidad; y iv. la adecuación al caso particular de aplicación. Se obtiene un conjunto de requerimientos considerados mínimos para el desarrollo de un emprendimiento productivo. Además, se identifican en el contexto local los procesos de mayor criticidad, relativos a la separación y la obtención del EPS y su provisión continua en el tiempo. Los resultados condensan aportes para contribuir a la replicación y la sostenibilidad de esta experiencia.Pesquisas anteriores desta equipe permitiram desenvolver e caracterizar um material isolante a partir de poliestireno expandido (EPS) descartado que pode ser utilizado na fabricação de placas, oferecendo oportunidades de trabalho a grupos sociais desempregados ou vulneráveis. Trabalhando em coordenação com uma cooperativa local de recicladores, foram determinados os processos de produção necessários para sua fabricação em escala adequada para a comercialização. O objetivo desta pesquisa é analisar os processos produtivos envolvidos e os aspectos críticos que tornam viável a execução e gestão desta tecnologia. A metodologia utilizada implica: i. a adequação do produto; ii. a determinação dos insumos e recursos para sua viabilidade; iii. a detecção dos processos com maior criticidade; e iv. a adaptação ao caso particular de aplicação. Obtém-se um conjunto de requisitos considerados mínimos para o desenvolvimento de um empreendimento produtivo. Além disso, são identificados no contexto local os processos mais críticos relacionados à separação e obtenção do EPS e seu fornecimento contínuo ao longo do tempo. Os resultados condensam contribuições que têm por objetivo a replicação e sustentabilidade desta experiência
Las reuniones de paz hispano-indígenas en la Araucanía durante el siglo XVI. Un estudio preliminar
Get PDFLos españoles se reunieron con los nativos de la Araucanía con el propósito de someterlos en paz, o a través de ella, al ordenamiento que pretendían implementar para alcanzar el dominio que deseaban. Sin embargo, estos iniciales encuentros no han sido debidamente analizados por los historiadores más allá de los inconvenientes que tuvieron para enseñorearlos, asumiendo que la paz fue una búsqueda incesante en los peninsulares.
Por otra parte, la resistencia no fue un capricho de estos naturales, razón por la que este estudio –el cual forma parte de una investigación en desarrollo–, aborda la problemática conceptual y de representación del término paz durante el siglo XVI. Con este propósito sometemos a crítica el término parlamento, lo que entendieron los nativos por estas reuniones y la ausencia de unidad por parte de los conglomerados indígenas para aceptarla, derivando en un conflicto interno entre ellas y también con los hispanos.The Spaniards met with the natives of Araucanía with the purpose of subjecting them in peace, or through it, to the order they intended to implement to achieve the domain they wanted. However, these initial meetings have not been properly analyzed by historians beyond the inconvenience they had to rule over them, assuming that peace was an incessant search in the peninsular.
On the other hand, the resistance was not a whim of these natives, which is why this study –which is part of a research in development–, addresses the conceptual and representational problems of the term peace during the 16th century. For this purpose, we subject the term parliament to criticism, what the natives understood from these meetings and the absence of unity among the indigenous conglomerates to accept it, leading to an internal conflict between them and also with Hispanics
Status of production, distribution and determinants of biomass briquette acceptability in kampala, uganda
Get PDFBiomass briquettes have been identified as a plausible and close alternative to commonly used energy fuels such as charcoal and firewood whose prices are escalating due to the dwindling natural resource base. However, briquettes do not seem to be as popular as would be expected. This study assessed the production, distribution and acceptability of the briquettes in Kampala district. A total of 60 respondents, 50 of whom were briquette users and 10 briquette producers were sampled from five divisions of Kampala district to evaluate consumer acceptability, preference for briquette type and shape. Households and institutions were identified to be the major consumers of briquettes while community-based organizations were the major distributors of briquettes. The Chi square test of independence showed significant association between briquette acceptability and briquette attributes of substitutability and low cost (p<0.05). The Kruskal Wallis test showed that low income class people preferred non-carbonized briquettes. Gender, marital status and income level also cause variation in preference for spherical, stick and honey comb briquettes (p<0.05). The major challenges faced by briquette users in Kampala were; production of a lot of ash, frequent crushing and limited access of briquettes. The producers of briquettes were mainly challenged by regular machine breakdown, raw material scarcity and poor carbonizing units. It was concluded that briquettes have market and are generally accepted in Kampala. However, user preferences need to be taken into account by briquette produces, suitable cook stoves should be availed to users and there is need for standards to ensure quality of briquettes
Quantitative evaluation of microwave irradiation on short-rotation plantation wood species
Get PDFThe durability of imported timber is a matter of growing concern in the tropical Indian climate, with their refractory nature further adding to the woes with respect to further processing. In the present study, the effect of microwave pre-treatment, exposure time and initial wood moisture content on retention, treatability and cross-sectional anatomical properties of Tectona grandis and Southern yellow pine imported from Ghana and South America were evaluated. Water based preservative copper chrome borate (CCB) of 2 % concentration was used for the study. The experimental study in combination with dip-diffusion method returned with significant improvement in retention of about 5-6 folds more than the control sets in Southern yellow pine and Tectona grandis. Another set of Southern yellow pine and Tectona grandis samples were further treated using a full cell pressure method after microwave, without initial vacuum, which showed similar trends with 3-4 folds increase in retention over controls. Both experiments returned with significant improvement in the treatability class of Tectona grandis and Southern yellow pine. Anatomical analysis was performed using a light microscope with 5 and 10x magnifications on treated and untreated samples of both Tectona grandis and Southern yellow pine. The outcome of the anatomical study exhibited improvement in vessel diameters in the treated samples of Tectona grandis with reduction in the degree of occlusion by presence of tyloses. For Southern yellow pine, checks on micro level and cracks on macro level appeared along the ray cells and the diameter of the resin canals were substantially expanded which ascertains that microwave pre-treatment ameliorated the flow of fluids in the wood microstructure which improved permeability and resulted in better uptake and penetration. 
Phenolics content and antioxidant activity of wood extractives from three clones of acacia hybrid (Acacia mangium × Acacia auriculiformis)
Get PDFThe objective of this study was to investigate the extractive content of three fast growing Acacia hybrid clones (Clone 16, 25, and 44) wood in three radial directions (SW = sapwood; OHW = outer heartwood; IHW = inner heartwood); total phenolic, flavonoid, flavanol contents (colorimetric assay); and antioxidant activity (1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assay). Extractions were done with three different solvents in successive (n-hexane = H; methanol = M; hot water = W), yielded 0,69 % – 1,70 %; 1,51 % – 10,86 %; and 0,51 % – 1,16 % of extractive contents, respectively. The total phenolic content (TPC) from TPC-H, TPC-M, and TPC-W ranged between 3,68 mg of gallic acid equivalent (GAE)/g – 10,41 mg GAE/g; 76,83 mg GAE/g – 448,35 mg GAE/g; and 43,28 mg GAE/g – 198,92 mg GAE/g, respectively; the total flavonoid content (TFC) from TFC-H, TFC-M, and TFC-W between 4,23 mg of quercetin equivalent (QE)/g – 41,51 mg QE/g; 29,55 mg QE/g – 133,71 mg QE/g; and 7,70 mg QE/g – 29,37 mg QE/g, respectively; total flavanol content (TVC) from TVC-H, TVC-M, and TVC-W ranged between 28,74 mg of catechin equivalent (CE)/g – 66,90 mg CE/g; 83,39 mg CE/g – 247,18 mg CE/g; and 7,08 mg CE/g – 29,21 mg CE/g, respectively. Furthermore, the antioxidant activity was found to be significantly affected by the radial factor with the strongest activity exhibited by inner heartwood extract with an IC50 value of 255,77 μg/ml (gallic acid IC50 showed a value of 39,00 μg/ml). Among clones, clone 16 was determined to have the highest extractive, total flavonoid as well as flavanol contents. Thus, clone 16 was hypothesized to be more resistance against heart rot disease
Effects of hot-cold oil treatment on biological resistance and physical properties of brutia pine sapwood
Get PDFThis study investigated the physical properties of hot-cold oil-treated Brutia pine sapwood (Pinus brutia) and its biological resistance against wood-decay fungi. Weight percent gain, density, water absorption, and volumetric shrinking were chosen as the physical properties of the wood. White rot (Trametes versicolor) and brown rot (Neolentinus lepideus) were selected as the wood-decay fungi. Two different temperatures and two different time intervals were determined for the hot-cold oil treatment. Castor oil (Ricinus communis), flaxseed oil (Oleum linii), and a mixture of the two were used as the treatment oils (the medium of the hot-cold treatment). The results showed that the physical properties of the hot-cold oil-treated samples improved significantly compared to those of the control samples. In addition, after exposure to the decay fungi, the mass loss of the hot-cold flaxseed oil-treated samples decreased significantly more than in either the untreated samples or those treated with the other oils. There was a significant increase in the water repellent effectiveness and dimensional stability of the Brutia pine sapwood with all hot-cold oil treatments, but the hot-cold castor oil treatment appeared to have had no effect on decay resistance. A hot-cold oil treatment using flaxseed oil or a mixture including it could be a suitable method for improvement of the water repellent effectiveness, dimensional stability, and decay resistance of Brutia pine sapwood, as they both reduced the water uptake and the mass loss against the wood-decay fungi compared to the results of the control samples
Bending moment resistance of t-type joints reinforced with basalt and glass woven fabric materials
Get PDFThis study investigated the bending moment resistance of T-type, two-pin dowel joints connected with Scotch pine dowel (Pinus slyvestris), beech dowel (Fagus orientalis), chestnut dowel (Castanea sativa) and oak dowel (Quercus petraea) and reinforced with basalt and glass woven fabric. The tests was carried out to determine the bending moment resistance of dowel joints. As a result of bending test, it was determined that one layer and two surfaces the reinforce with fiber woven fabrics increases the mechanical performance of furniture fasteners according to obtained data from tests conducted on the T-type, two pin dowel joints. The test samples prepared from the oak wooden give the higher moment values than the beech wooden. This study showed that the joining with the oak dowel was 13 % higher than the beech dowel, 32 % the chestnut dowel, and 43 % higher than the Scotch pine dowel (for the bending moment resistance), respectively. According to the bending moment resistance of the samples reinforced by fiber woven fabrics. The highest bending moment resistance value was obtained in the test specimens of reinforced with the basalt woven fabric, the lowest bending moment resistance value was obtained in the test specimens not reinforced (Control). In general, it was determined that the wood species by 3 %, wooden dowel species by 43 %, and fiber woven fabric types by 72 % have been effects on the results of the bending tests
Biologically synthesised copper oxide and zinc oxide nanoparticle formulation as an environmentally friendly wood protectant for the management of wood borer, Lyctus africanus
Get PDFThe management of Lyctus africanus, one of the major dry wood pests in the tropical region is difficult due to its secluded habits and long lifecycle and therefore, its control measures are limited to the usage of insecticides. The insecticides particularly the metal salts are effective, but in some cases their leaching leads to concerns about environmental pollution. Nanometal particles are found to be more effective than metal salts. Presently available metal nanoparticles are synthesized using physical or chemical methods and their production results in toxic by-products and are costly. The current investigation deals with synthesis and use of metal nanoparticle for wood protection in an environmentally friendly and cost-effective way. The plant extracts that are reported to have wood preservative properties were used for the synthesis of metal nanoparticles. Copper oxide and zinc oxide nanoparticles were synthesized using leaf extracts of Lantana camara. The efficacy of the synthesized Lantana camara leaf extract and copper oxide or zinc oxide nanoparticle formulation as a wood protectant was tested against Lyctus africanus as per BIS 4873 Part 2. The formulation of copper oxide nanoparticle and Lantana camara leaf extract effectively protected the treated rubberwood blocks from Lyctus africanus attack, when compared to zinc oxide nanoparticle Lantana camara leaf extract formulation and can be developed into a stable, ecofriendly wood preservative
Assessment of urban-territorial integration in Colombia
Get PDFEl énfasis en lo urbano dado por la Nueva Agenda Urbana (NAU) se complementa con una apuesta por una integración entre las ciudades y su entorno que busca fomentar un desarrollo territorial equitativo y equilibrado, sin embargo, se ofrecen en ella pocos detalles sobre cómo puede llevarse a cabo dicha integración. Esta es una cuestión de especial relevancia en el contexto latinoamericano, donde la desigualdad territorial constituye un elemento central en cualquier discusión sobre el desarrollo. A partir de una revisión de las implicaciones teóricas de la equidad y el equilibrio planteados en la NAU y de su contraste con los distintos planteamientos teóricos y propuestas conceptuales sobre desarrollo territorial, se expone aquí un análisis del caso colombiano. En este estudio se emplean indicadores a escala municipal que muestran cómo la relación entre las grandes ciudades y su entorno no son tan unívocas como propone la NAU, y que la prosperidad urbana puede en muchas ocasiones generar desequilibrios territoriales que deben ser atendidos específicamente.The urban emphasis given by the New Urban Agenda (NUA) is complemented by an attempt to integrate cities and their hinterland, which seeks to promote an equitable and balanced regional development. However, in the former, there are few details on how said integration can be achieved. This is a matter of special relevance in Latin America, where regional inequality is a key element in any discussion on development. An analysis of the Colombian case is presented here, starting from a review of the theoretical implications on equity and balance stated in NUA, and their comparison with different theoretical approaches and conceptual proposals on regional development. In this study, municipal level indicators are used to show how the relationship between large cities and their hinterland is not as linear as the NUA suggests, and that urban prosperity can often generate regional imbalances that require specific consideration