Vortex nucleation in mesoscopic Bose superfluid and breaking of the parity symmetry

We analyze vortex nucleation in mezoscopic 2D Bose superfluid in a rotating trap. We explicitly include a weakly anisotropic stirring potential, breaking thus explicitly the axial symmetry. As the rotation frequency passes the critical value $\Omega_c$ the system undergoes an extra symmetry change/breaking. Well below $\Omega_c$ the ground state is properly described by the mean field theory with an even condensate wave function. Well above $\Omega_c$ the MF solution works also well, but the order parameter becomes odd. This phenomenon involves therefore a discrete parity symmetry breaking. In the critical region the MF solutions exhibit dynamical instability. The true many body state is a strongly correlated entangled state involving two macroscopically occupied modes (eigenstates of the single particle density operator). We characterize this state in various aspects: i) the eligibility for adiabatic evolution; ii) its analytical approximation given by the maximally entangled combination of two single modes; and finally iii) its appearance in particle detection measurements.Comment: 14 pages, 27 figure

Ordered structures in rotating ultracold Bose gases

The characterization of small samples of cold bosonic atoms in rotating microtraps has recently attracted increasing interest due to the possibility to deal with a few number of particles per site in optical lattices. We analyze the evolution of ground state structures as the rotational frequency $\Omega$ increases. Various kinds of ordered structures are observed. For $N<10$ atoms, the standard scenario, valid for large sytems, is absent, and only gradually recovered as $N$ increases. The vortex contribution to the total angular momentum $L$ as a function of $\Omega$ ceases to be an increasing function of $\Omega$, as observed in experiments of Chevy {\it et al.} (Phys. Rev. Lett. 85, 2223 (2000)). Instead, for small $N$, it exhibits a sequence of peaks showing wide minima at the values of $\Omega$, where no vortices appear.Comment: 35 pages, 17 figure

Tecnologia social: uma estratégia para o desenvolvimento

Esta publicação apresenta reflexões de diversos representantes de instituições governamentais, do terceiro setor, da sociedade civil e de universidades sobre o tema da Tecnologia Social

Tecnologias sociais: as organizações não governamentais no enfrentamento das mudanças climáticas e na promoção de desenvolvimento humano

De acordo com o quarto relatório do Intergovernmental Panel on Climate Change (IPCC), as regiões semiáridas do mundo estarão entre as mais afetadas pelos impactos das mudanças climáticas globais. Estudos realizados pelo Ministério do Meio Ambiente (MMA), em 2007, confirmam que, no Nordeste brasileiro, não apenas choverá menos e mais irregularmente, mas, também, haverá mais secas, devido ao aquecimento da temperatura. Diante dos diversos impactos sociais, ambientais e econômicos possíveis nesses cenários, é de fundamental importância a verificação de alternativas sustentáveis para o semiárido brasileiro. Este artigo tem por objetivo avaliar o potencial de algumas das tecnologias sociais (TS) de convivência com o semiárido, desenvolvidas por diversas organizações, para a mitigação das mudanças climáticas e a promoção de desenvolvimento humano. Constata-se que as TS tem grande potencial para auxiliar na mitigação e na adaptação das mudanças climáticas, ao mesmo tempo que promovem melhorias na qualidade de vida das localidades onde estão sendo desenvolvidas

Co-opetition models for governing professional football

In recent years, models for co-creating value in a business-to-business context have often been examined with the aim of studying the strategies implemented by and among organisations for competitive and co-operative purposes. The traditional concepts of competition and co-operation between businesses have now evolved, both in terms of the sector in which the businesses operate and in terms of the type of goods they produce. Many researchers have, in recent times, investigated the determinants that can influence the way in which the model of co-opetition can be applied to the football world. Research interest lies in the particular features of what makes a good football. In this paper, the aim is to conduct an analysis of the rules governing the “football system”, while also looking at the determinants of the demand function within football entertainment. This entails applying to football match management the co-opetition model, a recognised model that combines competition and co-operation with the view of creating and distributing value. It can, therefore, be said that, for a spectator, watching sport is an experience of high suspense, and this suspense, in turn, depends upon the degree of uncertainty in the outcome. It follows that the rules ensuring that both these elements can be satisfied are a fertile ground for co-operation between clubs, as it is in the interest of all stakeholders to offer increasingly more attractive football, in comparison with other competing products. Our end purpose is to understand how co-opetition can be achieved within professional football

Estado e agricultores familiares: uma análise interpretativa sobre o desenvolvimento rural no Sul de Minas Gerais.

Este trabalho procurou identificar como os atores sociais vinculados à agricultura familiar (lideranças de produtores familiares, profissionais de ciências agrárias, autoridades municipais, pesquisadores e professores universitários) interpretam o papel do Estado para o desenvolvimento dessa categoria na região sul de Minas Gerais. Com relação à coleta de dados, utilizou-se a técnica "focused interview". Os entrevistados foram seledonados pelo método não-probabilístico de amostragem por julgamento. Os resultados revelaram que a interpretação feita pelos entrevistados aproxima-se mais da perspectiva do Estado patrimonialistaburocrático autoritário, tendo em vista que os depoimentos dos entrevistados corroboram com a reprodução das relações de dependência dos agricultores familiares em relação ao Estado. Por outro lado, alguns atores reconhecem a necessidade de mecanismos que incentivem a participação social, no entanto, salientaram que a mobilização dos produtores familiares na região ainda é incipiente e desarticulada

Reproductive traits of the invasive species Acacia dealbata Link. in the northern Mediterranean basin

Among the many exotic plants introduced in the last two centuries in Northern Mediterranean Basin Acacia dealbata Link. is one of the most invasive. Despite its presence in the region since many years, it has not yet been investigated how the species has established itself and has formed small forests. In this study, we aimed to gather data on reproductive trait of the invasive species A. dealbata at the northern limit of the Mediterranean bioclimatic region. In six naturalized populations, fruit and seed set were estimated and seed germination was tested in laboratory. Two out of the six populations failed to set fruits, and the fruit set was always low as observed in other invaded areas of the world. Only three populations produced germinating seeds whose rates were comparable to other invasive areas. The seeds may constitute a long-lasting seed bank that may favour the colonization of the species in areas disturbed by external factors. In conclusion, the reproductive system may contributes only partially to the spread and invasiveness of the species in the Northern Mediterranean basin, while the plant to spread itself adopts also other vegetative strategies

Developing Ontologies withing Decentralized Settings

This chapter addresses two research questions: “How should a well-engineered methodology facilitate the development of ontologies within communities of practice?” and “What methodology should be used?” If ontologies are to be developed by communities then the ontology development life cycle should be better understood within this context. This chapter presents the Melting Point (MP), a proposed new methodology for developing ontologies within decentralised settings. It describes how MP was developed by taking best practices from other methodologies, provides details on recommended steps and recommended processes, and compares MP with alternatives. The methodology presented here is the product of direct first-hand experience and observation of biological communities of practice in which some of the authors have been involved. The Melting Point is a methodology engineered for decentralised communities of practice for which the designers of technology and the users may be the same group. As such, MP provides a potential foundation for the establishment of standard practices for ontology engineering

Open-system orchestration as a relational source of sensing capabilities: Evidence from a venture association

Research on innovation networks has highlighted the pivotal role that actors with more prominence and power, such as hub firms, may play in orchestrating the activities of other network members along a collective innovation effort. Our study examined the undertheorized, but no less important, type of orchestration that characterizes other organizations, such as business incubators and venture associations, who seek to support the dispersed entrepreneurial efforts of network members. We refer to this type as ‘open-system’ orchestration, as opposed to the commonly studied ‘closed-system’ type performed by hub firms. Our findings reveal how the processes of open-system orchestration differ markedly from those of closed-system orchestration, and detail how these processes influence the micro-foundations of network members’ sensing capabilities. By doing so, we also offer empirical substantiation and theoretical elaboration to the idea that dynamic capabilities might not reside exclusively inside firms, but could be co-created relationally with other parties in the business ecosystem