Modelo de avaliação de risco : São o crescimento e a estequiometria dos girinos afetados pelo efeito interativo entre a presença do predador e da densidade de coespecíficos?

Many prey organisms change their phenotype to reduce the predation risk. However, such changes are associated with trade-offs, and can have negative effects on prey growth or reproduction. Understand how preys assess the predation risk is essential to evaluate the adaptive value of predator-induced phenotypic and its ecological consequences. In this study, we performed a mesocosm experiment to test: i) if growth and stoichiometry of Lithobates catesbeianus tadpoles is altered in response to giant water bug presence (Belostoma spp.); ii) if these responses depend on tadpoles density in environment. Here, we show that tadpoles growth and stoichiometry are not changed by predator presence, neither in low nor in high densities. Our results suggest that tadpoles exposed to predation risk regulate their physiology to preserve the elemental stoichiometric homeostase of their body and excretion. Further, point out to need for future studies that elucidate under what conditions growth and stoichiometry are changed in response to predation risk

Disturbance chemical cues determine changes in spatial occupation by the convict cichlid Archocentrus nigrofasciatus

I studied the effect of disturbance chemical cues on fish that make trade-offs between foraging in an open area and remaining in a safe refuge. I used convict cichlids Archocentrus nigrofasciatus that were either visually exposed to a predator (n = 8) or exposed to water conditioned by chemical cues from disturbed conspecifics (n = 8). Fish visually exposed to a predator decreased their ingestion rate and spent more time in the refuge than in the foraging area, while fish receiving water from frightened conspecifics did not alter their ingestion rate or time spent in the refuge and foraging site, but increased their spatial occupation (i.e., motion). These results suggest that convict cichlids recognized the predator by visual cues. Moreover, disturbance cues are a form of threatening public information that may increase fish spatial occupation due to increased exploring behaviour; but is not sufficiently alarming to alter feeding or increase refuge use. (C) 2004 Elsevier B.V. All rights reserved.

Seleção de flexibilidades de manufatura: uma analogia à carteira de ações para minimização de riscos e problemas no ambiente fabril

Para empresas de manufatura, vários autores recomendam a utilização da flexibilidade de manufatura para a minimização dos impactos prejudiciais que os riscos incutem às organizações. Entretanto, a característica multidimensional da flexibilidade de manufatura e os trade-offs existentes entre os diversos tipos dificultam a tarefa de se selecionar e adequar o grau de flexibilidade a ser adotado, frente às variáveis existentes. Além disso, a escolha indevida de tipos de flexibilidade para a solução de problemas pode gerar investimentos desnecessários e inadequados, ocasionando perda de capital e ineficiência no uso dos recursos flexíveis escolhidos para antecipação aos riscos. Assim, disponibilizar à gestão de operações resultados que permitam a seleção de diferentes tipos de flexibilidade, segundo as necessidades e a disponibilidade de recursos de cada empresa, torna-se crucial. Com esse propósito, efetuou-se uma pesquisa empírica que contemplou oito empresas de cinco segmentos industriais, na qual, por meio de uma analogia à diversificação de riscos em carteira de ações, propõe-se a composição de cinco diferentes tipos de carteiras de flexibilidades, para cinco diferentes segmentos industriais.

Preliminary Overview of the Economies of Latin America and the Caribbean 2007

Includes bibliography

Environmental evaluation of cogeneration scenarios in sugar industry

The development of new techniques that allow the analysis and optimization of energy systems bearing in mind environmental issues is indispensable in a world with finite natural resources and growing demand of energy. Among the energy systems that deserve special attention, cogeneration in the sugar industry must be pointed out, because it uses efficiently a common fuel for generation of useful heat and power. Within this frame, thermoeconomical optimization - 2nd Law of Thermodynamics analysis by exergy function and economic evaluation of the thermal system - gradually is taking importance as a powerful tool to assist to the decision making process. Also, the explicit consideration of environmental issues offers a better way to explore trade-offs between different aspects to support the decisions that must be made. In this work it is used the technique of Life Cycle Analysis (LCA) which allows to consider environmental matters as an integral part of the problem, in opposite to most of the environmental approaches that only reduce residuals generation , without taking into account impacts associated to other related processes. On the other hand, the consideration of environmental issues in optimization of energy systems is a novel and promissory contribution in the state of the art of energy optimization and LCA. The system under study is a sugar plant of Tucumán (Argentina) given the particular importance that this industry had inside the regional economy of the Argentinean Northwest. Although cogeneration comes being used a while ago in sugar industry, being the main objective the generation of heat and as secondary objective the electric power generation and mechanic power to cover several needs of working machineries, to the date it is no available a versatile tool that allows to analyze economical feasible alternatives bearing in mind environmental issues. At sugar plants, steam is generated in boilers using as fuel bagasse - cellulosic fiber waste obtained crushing the sugar cane- and it is used to give useful heat and shaft work to the plant, but it can also be used to generate electricity with export opportunities to the electrical network. The great number of process alternatives outlines a serious decision making problem in order to take advantage of the resources. Although the problem turns out to be a mixed non-linear problem (MINLP), the main contribution of this work is the development of a hybrid strategy to evaluate cogeneration alternatives that combines optimization approaches with environmental indicators. This powerful tool for its versatility and robustness to analyze cogeneration systems, will be of great help in the decision making process, because of their easy implementation to analyze the kind of problems presented in the sugar industry.

The Owner Share scheduler for a distributed system

In large distributed systems, where shared resources are owned by distinct entities, there is a need to reflect resource ownership in resource allocation. An appropriate resource management system should guarantee that resource's owners have access to a share of resources proportional to the share they provide. In order to achieve that some policies can be used for revoking access to resources currently used by other users. In this paper, a scheduling policy based in the concept of distributed ownership is introduced called Owner Share Enforcement Policy (OSEP). OSEP goal is to guarantee that owner do not have their jobs postponed for longer periods of time. We evaluate the results achieved with the application of this policy using metrics that describe policy violation, loss of capacity, policy cost and user satisfaction in environments with and without job checkpointing. We also evaluate and compare the OSEP policy with the Fair-Share policy, and from these results it is possible to capture the trade-offs from different ways to achieve fairness based on the user satisfaction. © 2009 IEEE.

Sustainable bioenergy: a framework for decision makers

Includes bibliography

Theory of constraints contributions to outbound logistics

Purpose: The purpose of this paper is to systematically describe the key practical contributions of the theory of constraints (TOC) to outbound (distribution) logistics. Design/methodology/approach: Based on theoretical research, this paper presents the main practical aspects of the approach suggested by TOC to outbound logistics and discusses the assumptions upon which it is based. Findings: This paper corroborates the thesis defended by TOC, according to which the current ways of managing outbound logistics, based mainly on sales forecasts lead to difficulties in handling trade-offs between logistics (stock and transportation) costs and stock-out levels. Research limitations/implications: The reported research is of a theoretical nature. Practical implications: TOC offers a proposal that is complementary in many aspects and very distinguishable in others about the way some key processes and elements of supply chain management (SCM) are managed, especially outbound logistics. Originality/value: Considering the dearth of papers dealing with the conceptual articulation and organization of this subject, the paper contributes to systematize the knowledge currently available about the contributions of the TOC to outbound logistics, highlighting the practical implications of applying TOC to outbound logistics. © Emerald Group Publishing Limited.

Economic efficiency of free and open source software in the public sector: the example of Chile

Includes bibliography

Alignment of operations strategy: Exploring the marketing interface

Purpose - The purpose of this paper is to identify factors that can help managers to overcome barriers to alignment of operations strategy at the interface with marketing. Design/methodology/approach - This objective required the application of a procedure based on strategic consensus and a deeper analysis, such that the delimitation of the study in a single case was mandatory. The strategic processes of interfacing involve managerial attributes that are subject to the influence of human aspects and, therefore, the research method used a qualitative approach. The protocol design included the following data sources: interviews, document reviews and researcher observations. The categorisation was made based on the theoretical references, the frequency of observations, common responses and information from documents. Findings - The balance between intra-functional trade-offs, joint research on the competitive context, reflections on the understanding of customer needs and operational performance, and understanding of inter-functional trade-offs were the main factors verified. They effectively support decisions associated with interface processes and promotes the integration of these processes. They can generate inputs that enable managers to achieve an appropriate balance among alternatives in light of various trade-offs. Practical implications - These factors make possible new connections between strategic processes in the context of operations and marketing functions. The formations of these strategies are aligned through a better understanding of both threats and opportunities by means of a joint analysis of the competitive context. The presented findings can be used to develop a clear definition of strategic objectives of operations and a more appropriate treatment of market needs. Originality/value - The findings from the research can be considered as new elements for promoting alignment in the formation process of the operations strategy. Little research to date has examined the operations-marketing strategic interface of companies in the context of strategic consensus. © Emerald Group Publishing Limited.

A model for computing vibration induced stresses of electronic components in a general flexible mounting

This paper develops a novel full analytic model for vibration analysis of solid-state electronic components. The model is just as accurate as finite element models and numerically light enough to permit for quick design trade-offs and statistical analysis. The paper shows the development of the model, comparison to finite elements and an application to a common engineering problem. A gull-wing flat pack component was selected as the benchmark test case, although the presented methodology is applicable to a wide range of component packages. Results showed very good agreement between the presented method and finite elements and demonstrated the usefulness of the method in how to use standard test data for a general application. © 2013 Elsevier Ltd.

Capital flows to Latin America: recent developments

Includes bibliography

CEPAL Review no. 115

Stylized features of the investment-growth connection in Latin America, 1980-2012 / Sandra Manuelito and Luis Felipe Jiménez.--International technological dynamics in production sectors: An empirical analysis / Fernando Isabella Revetria.-- Does public financial support stimulate innovation and productivity? An impact evaluation / Diego Aboal and Paula Garda.-- Digital inclusion in education in Tarija, Plurinational State of Bolivia / Sulma Farfán Sossa, Antonio Medina Rivilla and María Luz Cacheiro González.-- Macroeconomic trade-offs and external vulnerabilities of human development in Nicaragua / Marco V. Sánchez Cantillo.-- Classroom discipline, classroom environment and student performance in Chile / Carolina Gazmuri, Jorge Manzi and Ricardo D. Paredes.-- Pricing and spread components at the Lima Stock Exchange / Luis Chávez-Bedoya, Carlos Loaiza Álamo and Giannio Téllez De Vettori.-- Exports from the Brazilian automotive sector to the Southern Common Market: Trade diversion or cost reduction? / André Filipe Zago de Azevedo and Angélica Massuquetti.--Determinants of unfair inequality in Brazil, 1995 and 2009 / Ana Claudia Annegues, Erik Alencar de Figueiredo and Wallace Patrick Santos de Farias Souza.-- A comparative analysis of productivity in Brazilian and Mexican manufacturing industries / Armênio de Souza Rangel and Fernando Garcia de Freitas.

Escalonamento de tarefas em sistemas distribuídos baseado no conceito de propriedade distribuída

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Social instability promotes hormone-behavior associated patterns in a cichlid fish

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)