1,542 research outputs found

    Economic, environmental and mixed objective functions in non-linear process optimization using simulated annealing and tabu search

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    Screening of topologies developed by hierarchical heuristic procedures can be carried out by comparing their optimal performance. In this work we will be exploiting mono-objective process optimization using two algorithms, simulated annealing and tabu search, and four different objective functions: two of the net present value type, one of them including environmental costs and two of the global potential impact type. The hydrodealkylation of toluene to produce benzene was used as case study, considering five topologies with different complexities mainly obtained by including or not liquid recycling and heat integration. The performance of the algorithms together with the objective functions was observed, analyzed and discussed from various perspectives: average deviation of results for each algorithm, capacity for producing high purity product, screening of topologies, objective functions robustness in screening of topologies, trade-offs between economic and environmental type objective functions and variability of optimum solutions

    Uma metodologia simplificada para a avaliação de edifícios existentes e dimensionamento do reforço óptimo

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    Associado ao trabalho experimental, desenvolvido no laboratório ELSA, com vista à avaliação da capacidade original de estruturas representativas da prática de projecto e construção até finais dos anos 70, bem como da validação da eficiência de várias técnicas de reforço, foram utilizados e calibrados modelos numéricos refinados para a simulação dos resultados dos ensaios. Os modelos refinados calibrados com os resultados experimentais demonstraram ser adequados na determinação da resposta não-linear de estruturas existentes. Não obstante as potencialidades destes modelos, é reconhecido que a sua aplicação na avaliação de edifícios correntes pode ser trabalhosa e inadequada face às inúmeras incertezas que podem surgir. Assim, é proposta uma metodologia simplificada para a análise dinâmica não-linear de edifícios baseada no cálculo espectral multi-modal da resposta sísmica. Esta metodologia apresenta a possibilidade de avaliação de estruturas irregulares, e constitui-se como uma ferramenta útil para a optimização do reforço de edifícios existentes. Foi então também desenvolvida uma metodologia, baseada na optimização, para o dimensionamento óptimo do reforço para este tipo de estruturas. Esta comunicação apresenta as metodologias simplificadas desenvolvidas para a avaliação de edifícios existentes e dimensionamento do reforço óptimo

    Reforço sísmico do património edificado em betão armado

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    Sismos recentemente ocorridos em todo o mundo têm demonstrado que a investigação na engenharia sísmica deve ser direccionada para a avaliação da vulnerabilidade das construções existentes, desprovidas de adequadas características resistentes. O seu reforço deve ser realizado, reduzindo a sua vulnerabilidade e consequentemente o risco para níveis aceitáveis. O desenvolvimento de técnicas de reforço adequadas a este tipo de estruturas tem um papel principal. São descritas as causas mais frequentes de dano e colapso em edifícios existentes de betão armado e as técnicas de reforço mais adequadas para este tipo de estruturas. São brevemente apresentados os resultados mais relevantes de ensaios de avaliação do desempenho de estruturas existentes de betão armado, bem como de algumas técnicas de reforço. São discutidas as vantagens e limitações de cada uma destas técnicas

    Effect of breed on meat quality and global acceptance of native lambs and their crosses

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    International projections point to the growth in global production of sheep meat, mainly from developing countries. However, the exigencies of consumers on characterization of production systems, nutritional information, and sensorial analysis to target the preferences must be answered. The aim of this study was to characterize the meat quality and the global acceptance of Brazilian native ovine breeds and their crosses, and discuss these aspects on the current basis of human health and wellbeing. Three native breeds (Morada Nova, Rabo Largo, and Santa Inês) that were managed in semi-intensive systems and raised in semi-arid Brazilian regions were used. Chemical composition and fatty acid analysis, sensory evaluation and health indices were accessed. The combined effects of breed, sex and breed by sex interaction produced differentiation in meat fatty acid (FA) profiles. The cholesterol contents ranged between 51 and 59.1 mg/100 g. The Morada Nova lambs showed the lowest lipid content (1.93%). The Morada Nova x Rabo Largo crossbreed breed has the potential to increase the content of conjugated linoleic acid. The high content of α-linolenic acid, which is considered hypocholesterolemic, was responsible for better health indices. The moderate acceptability obtained in sensory traits is compatible with the requirements of the consumer market. The combination of nutritional and sensory traits associated with human health and wellbeing that is presented by these native ovine breeds qualifies them as a good choice of red meat to be included in a larger proportion in human food. Keywords: fatty acids, healthier meat, semi-arid region, shee

    Salivary Amylase Induction by Tannin-Enriched Diets as a Possible Countermeasure Against Tannins

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    Tannins are characterized by protein-binding affinity. They have astringent/bitter properties that act as deterrents, affecting diet selection. Two groups of salivary proteins, proline-rich proteins and histatins, are effective precipitators of tannin, decreasing levels of available tannins. The possibility of other salivary proteins having a co-adjuvant role on host defense mechanisms against tannins is unknown. In this work, we characterized and compared the protein profile of mice whole saliva from animals fed on three experimental diets: tannin-free diet, diet with the incorporation of 5% hydrolyzable tannins (tannic acid), or diet with 5% condensed tannins (quebracho). Protein analysis was performed by one-dimensional gel electrophoresis combined with Matrix-Assisted Laser Desorption Ionization-Time of Flight mass spectrometry to allow the dynamic study of interactions between diet and saliva. Since abundant salivary proteins obscure the purification and identification of medium and low expressed salivary proteins, we used centrifugation to obtain saliva samples free from proteins that precipitate after tannin binding. Data from Peptide Mass Fingerprinting allowed us to identify ten different proteins, some of them showing more than one isoform. Tannin-enriched diets were observed to change the salivary protein profile. One isoform of α-amylase was overexpressed with both types of tannins. Aldehyde reductase was only identified in saliva of the quebracho group. Additionally, a hypertrophy of parotid salivary gland acini was observed by histology, along with a decrease in body mass in the first 4 days of the experimental period

    Signal Transmission Across Tile Assemblies: 3D Static Tiles Simulate Active Self-Assembly by 2D Signal-Passing Tiles

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    The 2-Handed Assembly Model (2HAM) is a tile-based self-assembly model in which, typically beginning from single tiles, arbitrarily large aggregations of static tiles combine in pairs to form structures. The Signal-passing Tile Assembly Model (STAM) is an extension of the 2HAM in which the tiles are dynamically changing components which are able to alter their binding domains as they bind together. For our first result, we demonstrate useful techniques and transformations for converting an arbitrarily complex STAM+^+ tile set into an STAM+^+ tile set where every tile has a constant, low amount of complexity, in terms of the number and types of ``signals'' they can send, with a trade off in scale factor. Using these simplifications, we prove that for each temperature Ï„>1\tau>1 there exists a 3D tile set in the 2HAM which is intrinsically universal for the class of all 2D STAM+^+ systems at temperature Ï„\tau (where the STAM+^+ does not make use of the STAM's power of glue deactivation and assembly breaking, as the tile components of the 2HAM are static and unable to change or break bonds). This means that there is a single tile set UU in the 3D 2HAM which can, for an arbitrarily complex STAM+^+ system SS, be configured with a single input configuration which causes UU to exactly simulate SS at a scale factor dependent upon SS. Furthermore, this simulation uses only two planes of the third dimension. This implies that there exists a 3D tile set at temperature 22 in the 2HAM which is intrinsically universal for the class of all 2D STAM+^+ systems at temperature 11. Moreover, we show that for each temperature Ï„>1\tau>1 there exists an STAM+^+ tile set which is intrinsically universal for the class of all 2D STAM+^+ systems at temperature Ï„\tau, including the case where Ï„=1\tau = 1.Comment: A condensed version of this paper will appear in a special issue of Natural Computing for papers from DNA 19. This full version contains proofs not seen in the published versio

    A concentration phenomenon for semilinear elliptic equations

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    For a domain \Omega\subset\dR^N we consider the equation -\Delta u + V(x)u = Q_n(x)\abs{u}^{p-2}u with zero Dirichlet boundary conditions and p∈(2,2∗)p\in(2,2^*). Here V≥0V\ge 0 and QnQ_n are bounded functions that are positive in a region contained in Ω\Omega and negative outside, and such that the sets {Qn>0}\{Q_n>0\} shrink to a point x0∈Ωx_0\in\Omega as n→∞n\to\infty. We show that if unu_n is a nontrivial solution corresponding to QnQ_n, then the sequence (un)(u_n) concentrates at x0x_0 with respect to the H1H^1 and certain LqL^q-norms. We also show that if the sets {Qn>0}\{Q_n>0\} shrink to two points and unu_n are ground state solutions, then they concentrate at one of these points

    Comparison of Electrophoretic Protein Profiles from Sheep and Goat Parotid Saliva

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    Saliva provides a medium for short-term adaptation to changes in diet composition, namely, the presence of plant secondary metabolites. Salivary proteins have biological functions that have particular influence on oral homeostasis, taste, and digestive function. Some salivary proteins, such as proline-rich proteins, are present in browsers but absent in grazers. Despite the significance of salivary proteins, their expression patterns in many herbivores are unknown. We investigated the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile of parotid salivary proteins from two domesticated species, one a grazer, the sheep, Ovis aries, and the other a mixed feeder, the goat, Capra hircus, both fed on the same conventional diet. With 12.5% polyacrylamide linear gels, we observed uniform patterns of salivary proteins within the two species. In the goat profile, 21 major bands were observed, and 19 in the sheep profile. Each band was subjected to peptide mass fingerprinting for purposes of identification, allowing for 16 successful protein identifications. Marked differences were observed between the species in the region of 25–35 kDa molecular weights: one band was present in significantly different intensities; three bands were present only in goats; and one band was present only in sheep. This is the first report of a comparison of the protein salivary composition of sheep and goats and suggests that future research should be conducted to reveal a physiological function for salivary proteins related to the differences in feeding behavior of these species

    Environmental assessment of industrial production of microalgal biodiesel in central-south Chile

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    Biofuels from microalgae have the potential to replace fossil fuels, without competing with other products derived from crops. This study aims to perform a cradle-to-gate Life Cycle Assessment of the industrial production of microalgal biodiesel, using an autochthonous Chilean Phaeodactylum tricornutum strain, considering 1 MJ of biodiesel as the functional unit. For the compilation of the Life Cycle Inventory, real experimental data were obtained from the pilot-scale cultivation in a photobioreactor (PBR) module located in the city of Concepción, in Chile. The scale-up to the industrial plant considers that PBR modules are of the same size as those used in the pilot-scale. The Life Cycle Impacts Analysis considered the ReCiPe 2016 Endpoint (H) V1.00 method. Results show that the whole process contributes to a total of 5.74 kgCO2eq per MJ of biodiesel produced. PBR construction materials and energy consumption are the main contributors to the life cycle environmental impacts. The sensitivity analysis shows that energy consumption, water reuse and transportation distance of seawater from ocean to the industrial plant are the critical parameters that most affect the overall environmental performance of the system. The rate of water reuse is particularly critical to the global warming potential. Results also show that the valorization of co-products is an important aspect to improve the environmental performance of microalgal biodiesel production. Therefore, this study supports the decision-making process in biofuel production to promote the development of sustainable pilot and large-scale algae-based industry.publishe

    Leptospirosis in Campinas, São Paulo, Brazil : 2007-2014

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    Analisar a distribuição de casos e óbitos humanos por leptospirose, segundo características sociodemográficas, epidemiológicas, clínicas, tempo de atendimento, pluviosidade e distribuição espacial em Campinas, São Paulo, no período de 2007 a 2014. Estudo ecológico utilizando informações dos casos confirmados de leptospirose. Realizou-se análise descritiva dos casos, segundo variáveis selecionadas. A relação entre casos autóctones e pluviosidade foi verificada pelo coeficiente de correlação de Spearman. Georreferenciaram-se casos/óbitos por áreas classificadas segundo indicadores socioambientais. Dos 264 casos, 76,1% eram homens e 58,4% tinham entre 20 e 49 anos. Cerca de 55% foram hospitalizados. Prevaleceu o diagnóstico clínico-laboratorial (89,4%) e a letalidade foi de 10,6%. Na área urbana, ocorreram 74,2% dos casos e, 48,9%, no domicílio. O principal fator de risco foi o local com sinal de roedores. Houve forte correlação entre a incidência de casos e a pluviosidade (p < 0,05) nos anos de 2010 a 2012. Observou-se maior concentração de casos na região centro-sudoeste. A distribuição espacial dos casos/óbitos mostrou aglomerados em regiões classificadas como de menor nível socioeconômico. Os padrões de ocorrência de leptospirose em Campinas, São Paulo, mostraram similaridade com outras cidades brasileiras. A identificação de áreas com maior incidência de casos/óbitos contribui para a adoção de estratégias específicas de intervenção e priorização de recursos na redução do risco de infecção e tratamento precoce dos acometidos pela doença22To analyze the distribution of leptospirosis according to sociodemographic, epidemiologic, and clinical characteristics, assistance time, rainfall and spatial distribution in Campinas/SP in the period from 2007 to 2014. This is an ecological study using information from the confirmed cases. A descriptive analysis was carried out according to the selected variables. The relationship between the cases and rainfall was verified through the Spearman’s correlation coefficient. The cases/deaths were georeferenced per areas classified according to socioenvironmental deprivation indexes in Campinas. From the 264 cases, 76.1% occurred in men, 58,4% in the 20 to 49 years old age range. Approximately 55% were hospitalized, with a prevalence of clinical-laboratorial diagnoses of 89.4%, and the lethality was 10.6%. The urban area concentrated 74.2% of the cases, and 48,9% occurred in the household environment. The main risk factor was evidence of the presence of rodents at the site. There was strong correlation between the incidence of cases and rainfall (p < 0.05) in 2010 to 2012. A higher concentration of the cases was observed in the Center-Southwest region. Spatial distribution of cases/deaths showed clusters in regions classified at lower socioeconomic levels. The patterns of occurrence of leptospirosis in Campinas showed similarity with other Brazilian municipalities. The identification of areas with higher incidence of cases/deaths contributes to the adoption of strategies for intervention and prioritization of resources aiming at the reduction of the risk of infection and at early treatment for those affecte
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