856 resultados para Transformations in production


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Plastic wastes, and particularly plastic bags and sachets, are a major concern for urban and rural environment in African countries. In the last years some actions have been started for the plastic recycling like the artisanal production of paving blocks with melted plastic bags and sand, albeit with differences in production processes. Nevertheless, the environmental and economic impact of such activities is still to be confirmed. The aim of this study is to propose a methodology for assessing and comparing the environmental and energetic performances of artisanal methods, and for defining the overall quality of the produced blocks. This methodology has been shaped through the analysis of
production processes operated by artisans/small enterprises in West Africa and through physic-mechanical tests on the blocks. A questionnaire which allows an insight into the process and on the product has been developed and tested over five processes. Results show that a high input energy level is observed through all the processes, while considerable savings of energy could be achieved. Moreover, tests results confirmed the importance of the utilised plastic concerning thermal dilatation, mechanical resistance at higher temperature and cooling-shrinkage effects. In conclusion, doubts remain about the technical and environmental effectiveness of the sampled experiences, durability of the products and sustainability of this approach. Nevertheless, being the collection and recycling of plastic wastes a potential income generation activity for marginalised social groups in urban environment, a process optimisation could improve the impact of blocks production. Alternative recycling activities should also be considered.

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A marine Pseudomonas sp BTMS-51, immobilized by Ca-alginate gel entrapment was used for the production of extracellular Lglutaminase under repeated batch process and continuous process employing a packed bed reactor (PBR). Immobilized cells could produce an average of 25 U/ml of enzyme over 20 cycles of repeated batch operation and did not show any decline in production upon reuse. The enzyme yield correlated well with the biomass content in the beads. Continuous production of the enzyme in PBR was studied at different substrate concentrations and dilution rates. In general, the volumetric productivity increased with increased dilution rate and substrate concentrations and the substrate conversion efficiency declined. The PBR operated under conditions giving maximal substrate conversion efficiency gave an average yield of 21.07 U/ml and an average productivity of 13.49 U/ml/h. The system could be operated for 120 h without any decline in productivity

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At many locations in Myanmar, ongoing changes in land use have negative environmental impacts and threaten natural ecosystems at local, regional and national scales. In particular, the watershed area of Inle Lake in eastern Myanmar is strongly affected by the environmental effects of deforestation and soil erosion caused by agricultural intensification and expansion of agricultural land, which are exacerbated by the increasing population pressure and the growing number of tourists. This thesis, therefore, focuses on land use changes in traditional farming systems and their effects on socio-economic and biophysical factors to improve our understanding of sustainable natural resource management of this wetland ecosystem. The main objectives of this research were to: (1) assess the noticeable land transformations in space and time, (2) identify the typical farming systems as well as the divergent livelihood strategies, and finally, (3) estimate soil erosion risk in the different agro-ecological zones surrounding the Inle Lake watershed area. GIS and remote sensing techniques allowed to identify the dynamic land use and land cover changes (LUCC) during the past 40 years based on historical Corona images (1968) and Landsat images (1989, 2000 and 2009). In this study, 12 land cover classes were identified and a supervised classification was used for the Landsat datasets, whereas a visual interpretation approach was conducted for the Corona images. Within the past 40 years, the main landscape transformation processes were deforestation (- 49%), urbanization (+ 203%), agricultural expansion (+ 34%) with a notably increase of floating gardens (+ 390%), land abandonment (+ 167%), and marshlands losses in wetland area (- 83%) and water bodies (- 16%). The main driving forces of LUCC appeared to be high population growth, urbanization and settlements, a lack of sustainable land use and environmental management policies, wide-spread rural poverty, an open market economy and changes in market prices and access. To identify the diverse livelihood strategies in the Inle Lake watershed area and the diversity of income generating activities, household surveys were conducted (total: 301 households) using a stratified random sampling design in three different agro-ecological zones: floating gardens (FG), lowland cultivation (LL) and upland cultivation (UP). A cluster and discriminant analysis revealed that livelihood strategies and socio-economic situations of local communities differed significantly in the different zones. For all three zones, different livelihood strategies were identified which differed mainly in the amount of on-farm and off-farm income, and the level of income diversification. The gross margin for each household from agricultural production in the floating garden, lowland and upland cultivation was US$ 2108, 892 and 619 ha-1 respectively. Among the typical farming systems in these zones, tomato (Lycopersicon esculentum L.) plantation in the floating gardens yielded the highest net benefits, but caused negative environmental impacts given the overuse of inorganic fertilizers and pesticides. The Revised Universal Soil Loss Equation (RUSLE) and spatial analysis within GIS were applied to estimate soil erosion risk in the different agricultural zones and for the main cropping systems of the study region. The results revealed that the average soil losses in year 1989, 2000 and 2009 amounted to 20, 10 and 26 t ha-1, respectively and barren land along the steep slopes had the highest soil erosion risk with 85% of the total soil losses in the study area. Yearly fluctuations were mainly caused by changes in the amount of annual precipitation and the dynamics of LUCC such as deforestation and agriculture extension with inappropriate land use and unsustainable cropping systems. Among the typical cropping systems, upland rainfed rice (Oryza sativa L.) cultivation had the highest rate of soil erosion (20 t ha-1yr-1) followed by sebesten (Cordia dichotoma) and turmeric (Curcuma longa) plantation in the UP zone. This study indicated that the hotspot region of soil erosion risk were upland mountain areas, especially in the western part of the Inle lake. Soil conservation practices are thus urgently needed to control soil erosion and lake sedimentation and to conserve the wetland ecosystem. Most farmers have not yet implemented soil conservation measures to reduce soil erosion impacts such as land degradation, sedimentation and water pollution in Inle Lake, which is partly due to the low economic development and poverty in the region. Key challenges of agriculture in the hilly landscapes can be summarized as follows: fostering the sustainable land use of farming systems for the maintenance of ecosystem services and functions while improving the social and economic well-being of the population, integrated natural resources management policies and increasing the diversification of income opportunities to reduce pressure on forest and natural resources.

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[15-(CH3)-C-13-H-2]-dihydroartemisinic acid (2a) and [15-(CH3)-H-2]-dihydroartemisinic acid (2b) have been fed via the root to intact Artemisia annua plants and their transformations studied in vivo by one-dimensional H-2 NMR spectroscopy and two-dimensional, C-13-H-2 correlation NMR spectroscopy (C-13-(2) H COSY). Labelled dihydroartemisinic acid was transformed into 16 12-carboxy-amorphane and cadinane sesquiterpenes within a few days in the aerial parts of A. annua, although transformations in the root were much slower and more limited. Fifteen of these 16 metabolites have been reported previously as natural products from A. annua. Evidence is presented that the first step in the transformation of dihydroartemisinic acid in vivo is the formation of allylic hydroperoxides by the reaction of molecular oxygen with the Delta(4,5)-double bond in this compound. The origin of all 16 secondary metabolites might then be explained by the known further reactions of such hydroperoxides. The qualitative pattern for the transformations of dihydroartemisinic acid in vivo was essentially unaltered when a comparison was made between plants, which had been kept alive and plants which were allowed to die after feeding of the labelled precursor. This, coupled with the observation that the pattern of transformations of 2 in vivo demonstrated very close parallels with the spontaneous autoxidation chemistry for 2, which we have recently demonstrated in vitro, has lead us to conclude that the main 'metabolic route' for dihydroartemisinic acid in A. annua involves its spontaneous autoxidation and the subsequent spontaneous reactions of allylic hydroperoxides which are derived from 2. There may be no need to invoke the participation of enzymes in any of the later biogenetic steps leading to all 16 of the labelled 11,13-dihydro-amorphane sesquiterpenes which are found in A. annua as natural products. (C) 2003 Elsevier Ltd. All rights reserved.

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This thesis proposes that the idea expressed in Juvenal s quotation Mens Sana in Corpore Sano, produced in the Ancient Greek-Roman civilization includes undestandings of body, heath and education that were reapropriated and reorganized by scientific and pedagogical theories in the XIX and XX centuries. These theories, especially the ones that received contributions from the biomedical sciences, have influenced Physical Education in the search of becoming a science. In order to realize this reapropriation, we have analyzed the transformations in the concepts of body, health and education produced in the area discourse, aiming at pointing out elements to the configuration of a theory that is being called Corpore Sano. The theory constitutes in possible systematization of scientific, philosophical and pedagogical concepts, and as such, an understanding of the scientific fundaments of Physical Education. The corpus of this analysis was composed by 148 articles that were published in Revista Brasileira de Ciências do Esporte digitalized in the period between 1979 and 2003 and selected according to theme: body, biology, physical activity, effort physiology and health. The analysis of the content and the referential interpretation allowed the combination of philosophical reflection with attention to the empiric field as a comprehensive dimension. Based on the corpus of the analysis it is possible to configure meta-arguments about the concepts of body, health and education in the scientific production of Physical Education. As a metaresearch. Our study did not intend to judge the analyzed production, but look for theoretical elements that may generate a reflection about the scientific rationality in Physical Education and developments in the pedagogical field and in body practices. Such a reflection might be recognized as a theory of the living body, susceptible to modifications and interrogations that are proper of knowledge and practices of Physical Education. It is a theory rejects the idea of the complete truth and holds the comprehension that the truth is built historically through relations among different kinds of knowledge and Physical Education practices

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This article aims to analyse the introduction of environmental issues in the context of the production function, which has been referred to as the organisational area to lead corporate environmental management. With that purpose, the theoretical references for corporate environmental management and the necessary alterations in production function have been organised to include environmental aspects, especially in terms of product and process development, quality management, and logistics. Considering that this research field still lacks empirical evidence for Brazilian companies, four case studies were conducted using companies located in the country. The environmental management maturity level of those companies tends to follow the rate with which the environmental issue is introduced in production sub-areas, especially in the product development process. However, in most cases we found that the companies had difficulties in structuring the insertion of the environmental dimension in logistics. The final notes point out the distance observed between what is recommended by international literature and the reality of Brazilian companies in the challenge of making the production function environmentally friendly.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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In this study, the costs and gross income related to the production of pacu Piaractus mesopotamicus juveniles were evaluated. This evaluation took into consideration a semi-intensive rearing, with direct stocking of the larvae into fertilized ponds (IL 0), or an initial intensive larviculture system, in which the larvae were fed in the laboratory for 3 (IL 3), 6 (IL 6), or 9 days (IL 9) before being transferred to the ponds. After 45 days of rearing, a gradual increase in production costs was observed as intensive larviculture time increased. Gross income also increased due to better survival rates (11.0, 25.3, 45.4, and 54.0% for IL 0, IL 3, IL 6, and IL 9, respectively). Therefore, increased profits were obtained under intensive larviculture (US$ 0.27, US$ 6.07, US$ 11.99, and US$ 13.16 per one thousand larvae in treatments IL 0, IL 3, IL 6, and IL 9, respectively). In a larger scale production simulation, the results obtained with initial intensive larviculture also showed evident economic advantages, confirming the feasibility of this system in comparison with the direct stocking of larvae in ponds for the production of pacu juveniles. © 2004 Elsevier B.V. All rights reserved.

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Includes bibliography

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Includes bibliography

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Includes bibliography

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Includes bibliography

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Esta pesquisa investiga a infância na cidade de Belém do Pará, na primeira metade do século passado (1900 1950). A intenção é entender a realidade de crianças que viveram em uma época marcada por grandes transformações em nível econômico, político, social e cultural. A cidade de Belém vive, à época, um dos momentos mais prósperos de sua história, devido à grande produção da borracha que representava, até o final do século XIX, um dos maiores produtos de comercialização e exportação do país.Desta forma, o estudo procurou entender o contexto histórico, especialmente, na primeira metade do século XX. O apogeu da borracha levou a cidade a um surpreendente desenvolvimento, chegando a ser comparada às grandes cidades da Europa. Porém, todo o projeto modernizador executado na cidade traz conseqüências e contradições, que agravados pelo declínio da economia da borracha favoreceu, consideravelmente, as diferenças entre a elite emergente, que usufrui de todas as regalias oferecidas na cidade, e a classe menos favorecida que é colocada à margem de todo o processo. Dentro de todo esse cenário, encontra-se a criança que começa a ser vista como sujeito de direitos, no entanto, pouco se faz para que seus direitos sejam garantidos. Para entender a infância nesse período foram utilizadas narrativas de velhos que foram selecionados de acordo com os seguintes critérios: ter idade a partir de 80 anos; ter vivido a infância na cidade de Belém; ter condições físicas e psicológicas para lembrar e narrar sua infância. As narrativas foram determinantes para entender, por exemplo, aspectos da composição familiar que, naquele momento, eram marcados pelo respeito, pela obediência e, sobretudo, pela imposição; a relação da criança com o espaço público; a chegada da criança à escola para estudar, mesmo com todas as dificuldades impostas por um sistema que se encontrava em formação; as alternativas de lazer encontradas pelas crianças; as políticas de assistência à criança desamparada; entre outros. Além de autores que discutem e realizam pesquisa no âmbito da história oral como: Thompson, Alberti, Bosi, Vidal, dialogamos com outros da área da infância como: Kramer, Tozoni-Reis, Demartini, Rizzini, Ariès, e, também na área da historiografia e história da Amazônia como: Sarges, Figueiredo, Salles, Mendes, entre outros. Finalmente, a pesquisa privilegiou as narrativas que, em constante diálogo com os referenciais teóricos, foram o fio condutor da construção da história da infância na cidade de Belém.