Chemical ecology of insect parasitoids: towards a new era

Over the course of evolutionary time, insect parasitoids have developed diverse strategies for using chemical compounds to communicate with various protagonists within their environment (i.e. conspecifi cs, their hosts, and the plants on which their hosts are living). Unravelling the evolutionary meaning of such chemical communication networks not only provides new insights into the ecology of these insects but also contributes to improving the use of parasitoids for the control of insect pests in biological control programmes. A book covering our current knowledge of the chemical ecology of insect parasitoids is therefore particularly timely and will appeal to a large number of potential readers worldwide, from university students to senior scientists. Internationally recognized specialists were invited to contribute chapters to this book, examining the main topics and exploring the most interesting issues in the fi eld of chemical ecology of insect parasitoids. The chapters are organized so as to present the most signifi cant knowledge and discoveries made over recent decades, and their potential uses in pest control

Effect of host kairomones and oviposition experience on the arrestment behavior of an egg parasitoid

Chemical residues left by walking adults of the southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae) induce arrestment behavior in the egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) leading to prolonged periods of walking on contaminated areas and to systematic return to the stimulus after encountering the treatment borders. In this study, we quantified how the hierarchical value of residues from host adults and oviposition experience can influence the arrestment behavior of T. basalis females. Our results showed that: (1) female wasps perceived host residues at different hierarchical levels depending on the host gender, with a clear preference for the chemical residues deposited by host females rather then host males; (2) wasps' arrestment response to chemical residues of host females became weaker when wasps were not rewarded by an oviposition experience, and stronger following successful oviposition; (3) repeated encounters with host male chemical residues, followed or not by oviposition experience, did not cause wasps to change their innate arrestment response; (4) in the unrewarded condition, arrestment responses of wasps varied according to the time elapsed between successive visits to areas contaminated by host females: responses were weak with a short interval (less than 24 h) and stronger with a long interval (more than 72 h), suggesting that this unrewarded experience, i.e. encounter with female traces not followed by host egg location, fade within a few hours. The potential significance of these results to the host location behavior of T. basalis in the field is discussed

Intraguild interactions between two egg parasitoids of a true bug in semi-field and field conditions

Research on interspecific competitive interactions among insect parasitoids has often been characterized by laboratory studies in which host insects are exposed to female parasitoids of different species in various sequences and combinations. In the last years, an increasing number of studies have investigated interspecific interactions under field and semi-field conditions although just a few number of works focused on egg parasitoids. In this work, we undertook a two-year study to investigate interspecific interactions between Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), two egg parasitoids of the pest Nezara viridula (L.) (Heteroptera: Pentatomidae) that co-occur in cultivated crops. Under semi-field (in out-door mesh cages) and field conditions, we investigated: 1) the seasonal occurrence of competing parasitoid species on sentinel egg masses; 2) the impact achieved by competing species on the shared host on naturally laid egg masses; 3) the outcome of intraguild interactions under controlled conditions. Results from sentinel egg masses showed that T. basalis occurs in May and successfully parasitizes hosts until the end of September/beginning of October, whereas O. telenomicida is mainly occurring in July-August. In both years, it was found that T. basalis is predominant. From naturally laid egg masses, results indicated that T. basalis achieves higher impact on the hosts, even in those egg masses which are parasitized by more than one female of different species ( = multiparasitism). Results from manipulating intraguild interactions showed that T. basalis achieves higher impact on N. viridula when released alone, but it suffers from competition with O. telenomicida. The ecological factors that play a role in intraguild interactions in the context of biological control perspective are discussed

Teatro dos quatro: heranças e influências a partir de uma possível filiação a um teatro de texto

A proposta central do Teatro dos Quatro – fundado e mantido por uma sociedade formada por Sergio Britto, Paulo Mamede e Mimina Roveda entre 1978 e 1993 – era bastante clara, desde o início da implantação do projeto: investir em montagens de textos renomados, que valorizassem as qualidades dramatúrgicas em detrimento de eventuais visões diretoriais que se sobrepusessem a elas, interpretadas por uma vasta galeria de atores, formada entre os profissionais mais importantes em atividade no Brasil. Mas esta “definição” não deve ser considerada em termos absolutos, especialmente porque seria apressado definir os trabalhos de direção das encenações do Teatro dos Quatro como textocentristas, ou seja, subservientes a um determinado texto

SNAP : mecanismo de contabilidade hídrica em áreas urbanas para melhoria na eficiência econômica de alocação e sinalização da escassez

A cobrança pelo uso da água, desde sua concepção, objetiva reconhecer a água como um bem econômico, dando ao usuário uma indicação de seu real valor, incentivando, ainda, a racionalização do seu uso; entretanto, percebe-se que seus propósitos principais não estão sendo plenamente atingidos. Tal limitação deve-se, dentre outros aspectos, às dificuldades do usuário em perceber o retorno do investimento dessa cobrança. Além disso, os baixos valores cobrados não refletem o valor econômico da água, sendo incapazes de sinalizar períodos de escassez hídrica. Por outro lado, o simples aumento dos valores cobrados a partir da criação de tarifas de contingência no âmbito do saneamento é um caminho complexo, com grandes desafios políticos, que por vezes apresenta inclusive vulnerabilidade jurídica. O controle às externalidades resultantes do uso da água no meio urbano é ainda mais difícil de ser incorporado pelos usuários, uma vez que a água não é utilizada como insumo para um bem comercializável - como no caso da produção agrícola -, mas sim para sanar as necessidades básicas e gerar bem-estar. Nesse contexto, temos ainda uma lacuna para sinalizar a escassez e melhorar a eficiência econômica na distribuição da água em áreas urbanas, especialmente durante eventos de crise hídrica. O presente estudo traz uma contribuição para essa lacuna, na forma de um mecanismo de contabilidade hídrica no meio urbano que visa estimular o usuário a incorporar o valor da água no seu cotidiano, sinalizando a escassez desse bem de forma direta. O mecanismo de contabilidade hídrica proposto é o Sistema de Negociação e Alocação de curto Prazo (SNAP), um instrumento econômico desenvolvido com base nos custos e valores marginais da água para diferentes perfis de consumo, incorporando Cotas Hídricas Realocáveis no extrato da conta de água mensal. Como área de aplicação da metodologia proposta, foi escolhida a Região Administrativa Cruzeiro, em Brasília – DF, a qual passou por um período expressivo de crise hídrica e restrições de abastecimento entre 2016 e 2018, onde a gestão dos recursos hídricos é realizada pela ADASA, e o abastecimento, pela CAESB. Os resultados demonstraram que é possível incorporar aos atuais sistemas de abastecimento urbano os conceitos de realocação e eficiência econômica. Com isso, tais sistemas se tornam mais robustos e com alternativas de decisão aos usuários, mesmo quando necessária a implementação de medidas restritivas de acesso à água, como o racionamento. Além disso, as alternativas do SNAP viabilizaram ganhos em termos de diminuição do custo da escassez, aumento na arrecadação, sinalização aos usuários do valor da água, bem como indução ao uso racional.The charging for the use of water, from its conception, aims to recognize water as an economic resource, providing the user with an indication of its real value, while also encouraging its rational use. However, it is clear that its main purposes are not being fully achieved, among other aspects, due to the user's difficulties in recognizing the returns from the investments realized by the charge. In addition, the low values charged do not reflect the economic value of the water, being unable to indicate water scarcity periods. On the other hand, increasing the amounts charged with contingency tariffs is a complex way, with large political challenges and legal vulnerability. The externalities resulting from urban water use are even more difficult for users to control, since water is not used as an input for a tradable good - as in the case of agricultural production -, but to meet basic needs and generate wellbeing. In this context, there still a gap on signaling water scarcity and improving the economic efficiency of water supply systems in urban areas, especially during water crisis events. The study presents a contribution towards resolving these issues in the form of a water accounting mechanism in the urban environment that aims to stimulate users to incorporate the value of water in their daily lives, directly signaling the scarcity of this good. The proposed water accounting mechanism is the Short term Negotiation and Allocation Policy (SNAP), an economic instrument developed based on the costs and marginal values of water for different consumption profiles, incorporating Relocatable Water Quotas in monthly water bill. The Cruzeiro Administrative Region, in Brasília - DF, which went through a significant period of water crisis and supply restrictions between 2016 and 2018, was chosen as a case study for the application of the proposed methodology. The management of water resources and water supply during this period was carried out by ADASA and CAESB. The findings show it is possible to incorporate the concepts of relocation and economic efficiency into the current urban water supply systems. As a result, such systems become more robust and provide users with possibilities of consumption decisions, even when it is necessary to implement restrictive measures regarding access to water, such as rationing. In addition, the SNAP alternatives enabled gains in terms of reducing the water scarcity cost, increasing collections, signaling users of the value of water, as well as inducing rational use

Mining process factor causality links with multi-relational associations

International audienceTo make knowledge-supported decisions, industrial actors often need to examine available data for suggestive patterns. As industrial data are typically unlabeled and involve multiple object types, unsupervised multi-relational (MR) data mining methods are particularly suitable for the task. Current MR association miners merely produce singleton-conclusions rules hence might miss multi-way dependencies. Our novel MR miner builds upon a relational extension of concept analysis to extract general associations. While successfully dealing with circularity in data, it avoids producing cyclic rules by limiting the description depth of relational concepts. Our rules' relevance was validated by an application to aluminum die casting

Debêntures de projetos de infraestrutura: uma comparação entre as experiências brasileira e internacional

Bibliografia: p. 149-155.O artigo compara as experiências nacionais e internacionais no uso das debêntures de projetos (project bonds), com o objetivo de verificar, por um lado, em que aspectos a utilização do instrumento no contexto doméstico está alinhada com o que ocorre em mercados desenvolvidos, ou, por outro lado, em que medida o Brasil está usando o instrumento de forma diferente dos mercados maduros. Entende-se que a comparação com a prática internacional pode ensejar reflexões sobre a adequação das políticas públicas e das práticas vigentes na utilização do instrumento. As evidências apontam que, em relação ao mercado internacional, as debêntures de projetos no Brasil: (i) foram emitidas por setores que também são emissores nos mercados internacionais, embora nestes últimos seja observada maior diversificação setorial; (ii) ocorreram em portes menores; (iii) demonstraram prazos consideravelmente mais curtos; (iv) desempenharam papel igualmente complementar, porém, quando emitidas, ocuparam parcela menor do funding; (v) foram adquiridas por base de investidores diversa; e (vi) diferentemente do contexto internacional, não foram acompanhadas de mecanismos de reforço de crédito.This article aims to compare national and international experiences about the use of project bonds, to verify, on one hand, in what aspects the use of this instrument in the domestic context is aligned with what occurs in developed markets, or, on the other hand, to what extent Brazil has been using the instrument differently from mature markets. It is understood that the comparison with the international practice can lead to reflections on the adequacy of public policies and current practices in the use of this instrument. Regarding the international market, project bonds in Brazil: (i) were issued by sectors that are also issuers in international markets, although a greater sector diversification is observed in the last ones; (ii) had lower issue volumes; (iii) had showed shorter term payments; (iv) also played a supplementary role, however, when issued, the bonds had smaller funding share; (v) were subscribed by a diverse investor base; (vi) unlike the international context, they were not followed by credit enhancement mechanisms