On a class of non-self-adjoint periodic eigenproblems with boundary and interior singularities

We prove that all the eigenvalues of a certain highly non-self-adjoint Sturm–Liouville differential operator are real. The results presented are motivated by and extend those recently found by various authors (Benilov et al. (2003) [3], Davies (2007) [7] and Weir (2008) [18]) on the stability of a model describing small oscillations of a thin layer of fluid inside a rotating cylinder.

Stable receding horizon control based on recurrent networks

The last decade has seen the re-emergence of artificial neural networks as an alternative to traditional modelling techniques for the control of nonlinear systems. Numerous control schemes have been proposed and have been shown to work in simulations. However, very few analyses have been made of the working of these networks. The authors show that a receding horizon control strategy based on a class of recurrent networks can stabilise nonlinear systems.

Asset allocation, cross-class correlation and the structure of property returns

Practical applications of portfolio optimisation tend to proceed on a “top down” basis where funds are allocated first at asset class level (between, say, bonds, cash, equities and real estate) and then, progressively, at sub-class level (within property to sectors, office, retail, industrial for example). While there are organisational benefits from such an approach, it can potentially lead to sub-optimal allocations when compared to a “global” or “side-by-side” optimisation. This will occur where there are correlations between sub-classes across the asset divide that are masked in aggregation – between, for instance, City offices and the performance of financial services stocks. This paper explores such sub-class linkages using UK monthly stock and property data. Exploratory analysis using clustering procedures and factor analysis suggests that property performance and equity performance are distinctive: there is little persuasive evidence of contemporaneous or lagged sub-class linkages. Formal tests of the equivalence of optimised portfolios using top-down and global approaches failed to demonstrate significant differences, whether or not allocations were constrained. While the results may be a function of measurement of market returns, it is those returns that are used to assess fund performance. Accordingly, the treatment of real estate as a distinct asset class with diversification potential seems justified.

‘Did Ronald McDonald also tend to scare you as a child?’: working to emplace consumption, commodities, and citizen-students in a large classroom setting

So-called ‘radical’ and ‘critical’ pedagogy seems to be everywhere these days on the landscapes of geographical teaching praxis and theory. Part of the remit of radical/critical pedagogy involves a de-centring of the traditional ‘banking’ method of pedagogical praxis. Yet, how do we challenge this ‘banking’ model of knowledge transmission in both a large-class setting and around the topic of commodity geographies where the banking model of information transfer still holds sway? This paper presents a theoretically and pedagogically driven argument, as well as a series of practical teaching ‘techniques’ and tools—mind-mapping and group work—designed to promote ‘deep learning’ and a progressive political potential in a first-year large-scale geography course centred around lectures on the Geographies of Consumption and Material Culture. Here students are not only asked to place themselves within and without the academic materials and other media but are urged to make intimate connections between themselves and their own consumptive acts and the commodity networks in which they are enmeshed. Thus, perhaps pedagogy needs to be emplaced firmly within the realms of research practice rather than as simply the transference of research findings.

Perfective marking in L2 Mandarin: agreement with inherent lexical aspect or the derived Sentential Aspectual class?

This study evaluates the differing claims of the Aspect Hypothesis (Anderson & Shirai 1996) and the Sentential Aspect Hypothesis (Sharma & Deo 2009) for perfective marking by L1 English learners of Mandarin. The AH predicts a narrow focus on inherent lexical aspect (the verb and predicate) in determining the use of the perfective marker le, whilst the SAH suggests that – subject to L1 influence – perfective marking agrees with the final derived aspectual class of the sentence. To test these claims data were collected using a controlled le-insertion task, combined with oral corpus data. The results show that learners’ perfective marking patterns with the sentential aspectual class and not inherent lexical aspect (where these differ), and that overall the sentential aspectual class better predicts learners’ assignment of perfective marking than lexical aspect.

Overcoming your child’s fears and worries: guided self-help manual for therapists working with groups

This manual for therapists accompanies ‘Overcoming your child’s fears and worries’ (Creswell & Willetts, 2007), a guide for parents to help their children overcome difficulties with anxiety

Contribuições para a formação do administrador no mundo contemporâneo: uma abordagem psicossocial

Esta pesquisa pretendeu investigar possíveis articulações, dos alunos no curso de graduação em administração, entre a idealização do papel de futuro profissional, a dinâmica da classe e a demanda do mercado de trabalho contemporâneo. Os sujeitos foram 50 (cinqüenta) alunos da disciplina de Psicologia no segundo semestre do curso de administração e seus professores. Centramos esta investigação em entrevistas com alunos, observação da dinâmica interacional presente na classe, devolutiva do processo grupal em seminário com alunos, análise dos exames finais; aplicação de questionários a professores; levantamento bibliográfico dos teóricos da administração na área de relacionamento interpessoal. Perguntamo-nos: como alunos, professores e teóricos definem o administrador competente? Que estratégias facilitam a formação das competências necessárias para o administrador contemporâneo? Quais seriam as possíveis estratégias facilitadoras para a formação dessas competências na graduação?

Price discovery in dual-class shares across multiple markets

We extend the standard price discovery analysis to estimate the information share of dual-class shares across domestic and foreign markets. By examining both common and preferred shares, we aim to extract information not only about the fundamental value of the rm, but also about the dual-class premium. In particular, our interest lies on the price discovery mechanism regulating the prices of common and preferred shares in the BM&FBovespa as well as the prices of their ADR counterparts in the NYSE and in the Arca platform. However, in the presence of contemporaneous correlation between the innovations, the standard information share measure depends heavily on the ordering we attribute to prices in the system. To remain agnostic about which are the leading share class and market, one could for instance compute some weighted average information share across all possible orderings. This is extremely inconvenient given that we are dealing with 2 share prices in Brazil, 4 share prices in the US, plus the exchange rate (and hence over 5,000 permutations!). We thus develop a novel methodology to carry out price discovery analyses that does not impose any ex-ante assumption about which share class or trading platform conveys more information about shocks in the fundamental price. As such, our procedure yields a single measure of information share, which is invariant to the ordering of the variables in the system. Simulations of a simple market microstructure model show that our information share estimator works pretty well in practice. We then employ transactions data to study price discovery in two dual-class Brazilian stocks and their ADRs. We uncover two interesting ndings. First, the foreign market is at least as informative as the home market. Second, shocks in the dual-class premium entail a permanent e ect in normal times, but transitory in periods of nancial distress. We argue that the latter is consistent with the expropriation of preferred shareholders as a class.

A class of improved heteroskedasticity-consistent covariance matrix estimators

The heteroskedasticity-consistent covariance matrix estimator proposed by White (1980), also known as HC0, is commonly used in practical applications and is implemented into a number of statistical software. Cribari–Neto, Ferrari & Cordeiro (2000) have developed a bias-adjustment scheme that delivers bias-corrected White estimators. There are several variants of the original White estimator that also commonly used by practitioners. These include the HC1, HC2 and HC3 estimators, which have proven to have superior small-sample behavior relative to White’s estimator. This paper defines a general bias-correction mechamism that can be applied not only to White’s estimator, but to variants of this estimator as well, such as HC1, HC2 and HC3. Numerical evidence on the usefulness of the proposed corrections is also presented. Overall, the results favor the sequence of improved HC2 estimators.

Developmental class coalitions: historical experiences and prospects

Este artigo discute o conceito de coalizões de classe como uma alternativa parcial à luta de classes na compreensão das sociedades capitalistas; define duas coalizões de classes básicas - a desenvolvimentista e a liberal; apresenta brevemente três coalizões de classe desenvolvimentistas paradigmáticas - a mercantilista, a bismarckiana, e a social-democrata (ou dos anos dourados do capitalismo); e usa esse arcabouço teórico para entender o capitalismo contemporâneo nos anos pós neoliberais - os anos que se seguem a crise financeira global de 2008

A retrospective look at esthetic resin composite and glass-ionomer Class III restorations: A 2-year clinical evaluation

Objective: A restorative material for Class III cavities must, besides being functional, be esthetically satisfactory, providing good working conditions and several shade and color options. A clinical evaluation was initiated to compare the suitability of resin composite and glass-ionomer cement materials for such restorations.Method and materials: Forty-two Class III conservative cavities, esthetically important because of facial extensions, were selected. Resin composite restorations were placed in 21 cavities, and the remaining 21 were restored with glass-ionomer cement. The following characteristics were studied: color or-esthetics, anatomic shape, surface texture, staining, marginal infiltration, dental plaque retention, and occurrence of fracture. After 24 months, the restorations were evaluated.Results: the only statistically significant difference between the resin composite and glass-ionomer cement restorations in the experimental period involved color or esthetics.Conclusion: Resin composites and glass-ionomer materials provide excellent functional and esthetic results in Class III cavities when properly indicated.

Lagrangian heuristic for a class of the generalized assignment problems

A Lagrangian based heuristic is proposed for many-to-many assignment problems taking into account capacity limits for task and agents. A modified Lagrangian bound studied earlier by the authors is presented and a greedy heuristic is then applied to get a feasible Lagrangian-based solution. The latter is also used to speed up the subgradient scheme to solve the modified Lagrangian dual problem. A numerical study is presented to demonstrate the efficiency of the proposed approach. (C) 2010 Elsevier Ltd. All rights reserved.

Compreensão escrita em manuais didáticos de PLE

Foram analisadas nessa pesquisa as propostas de compreensão textual em manuais utilizados em cursos básicos de Português como Língua Estrangeira (PLE) em Belém-Pa. Foi investigado também como as propostas são desenvolvidas pelas professoras em sala de aula. Os objetos de estudo foram materiais instrucionais da Universidade Federal do Pará (UFPA) e da School for International Training (SIT). Para os alunos de ambas as instituições, a habilidade de compreensão escrita na Língua Estrangeira (LE) é imprescindível. Todos necessitam ler em português para participar ativamente da sociedade em que agora vivem. Entretanto, cada público também se vale da leitura para atividades específicas. Assim, esses alunos precisam ler diferentes textos em LE por diversas razões e em várias situações. Daí a importância de usar em sala de aula manuais que favoreçam o desenvolvimento da compreensão escrita dos alunos propondo textos, atividades e estratégias adequados ao público-alvo. Este trabalho foi desenvolvido com o objetivo de investigar as propostas de compreensão escrita nos manuais de PLE assim como sua operacionalização nos cursos em questão e contribuir assim para o aperfeiçoamento das práticas de sala de aula, levando em conta ainda opiniões de professores e alunos sobre o trabalho com essa habilidade. O estudo em questão foi realizado a partir de pesquisa bibliográfica e de campo. A pesquisa bibliográfica baseou-se em autores como Alliende e Condemarín (2005), Koch e Elias (2007), Farrell (2003), Henk et al (2000), Marcuschi (2008), e Nuttall (2005), entre outros. A pesquisa de campo se deu no curso de PLE das instituições mencionadas e teve como população-amostra alunos e professoras que ministraram aula para o nível básico de cada uma das instituições no primeiro semestre de 2011. Foram utilizados dados de três fontes nesta investigação: análise dos manuais e do questionário aplicado aos alunos e professoras, além da observação de aulas usando o material. Ao final da pesquisa, constatamos que as propostas de ambos os manuais ainda estão longe de proporcionar oportunidades adequadas de desenvolvimento da habilidade de ler em uma LE e também que trabalhar com um manual produzido artesanalmente pode não ser a melhor opção, embora ainda seja muito forte a ideia de que não há LD que atenda as necessidades de determinado grupo de alunos.

The restructuring of labour in Brazil in the 2000s: flexible work and the precarisation of working life

This article argues that the precarisation of employment that has taken place in Brazil since the 1990s has been fundamentally different in kind from earlier forms of precariousness, which took place outside the formal economy. The new forms of precariousness are taking place within the sphere of the economy controlled by transnational corporations. Although they have only reached critical mass during the 2000s, the ground was prepared by ‘post neoliberal’ restructuring, including labour law reforms, that took place in Brazil during the 1990s and introduced new forms of flexible working. The article argues that the new condition of labour now emerging in Brazil, which is a structural feature of labour under global capitalism, is characterised by psychosocial dynamics that cause: first, class desubjectivation; second, a ‘seizure’ of the waged worker's subjectivity; and third, the reduction of living labour to the status of a workforce treated as goods. Comprehending these changes necessitates a related change in the theoretical and methodological framework in which the precariousness of work is studied, one that incorporates within its scope the issues of workers' health and the quality of working life.