1,371 research outputs found

    A stronger topology for the Brownian web

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    We propose a metric space of coalescing pairs of paths on which we are able to prove (more or less) directly convergence of objects such as the persistence probability in the (one dimensional, nearest neighbor, symmetric) voter model or the diffusively rescaled weight distribution in a silo model (as well as the equivalent output distribution in a river basin model), interpreted in terms of (dual) diffusively rescaled coalescing random walks, to corresponding objects defined in terms of the Brownian web.Comment: 22 page

    Understanding the topologies of innovation networks in knowledge-intensive sectors

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    The main goal of this paper is to compare the networks mobilised by young entrepreneurial firms from two knowledge intensive sectors – molecular biotechnology and software for telecommunications – to access resources required for innovation. Such a comparison allows similarities and differences between networks to be identified and explained. The analysis focuses on formal and informal networks and on the relevant types of resources. It applies a methodology that draws on a vast array of data to capture the nature and content of a broad range of relationships developed by the firms in their innovative process. The results show that networks are quite contrasted in and across the two sectors, due both to the specificity of the resources searched for and the mode of organisation of the sectors. Furthermore, the results shed light on the specificities of formal versus informal networks. Finally, they provide novel insights into the organisation and dynamics of the sectors, taking into account both the characteristics and strategies of the firms and the specificity of the environment in the Portuguese case. The approach provides tools to study the innovative process in knowledge intensive sectors which may be applied to different national and sectoral contexts.FC

    Building a bridge: social networks and technological regimes in biotechnology and software

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    The paper investigates the influence of technological regimes on the composition and structure of firms’ knowledge networks. We combine insights from two hitherto unconnected bodies of research: one relating technological regimes with the nature of knowledge; and the other relating knowledge and types of innovation with network configuration. Drawing on this framework, we build a number of propositions on the relationship between firms’ networking behaviour and the regime under which they operate, operationalized at both sector and firm-level. These propositions are explored through empirical research comparing firms operating in two distinct knowledge-intensive sectors, namely biotechnology, which is commonly considered more science-based, and software, thought of as mostly technology-based. As expected, we found that distinct technological regimes affect the knowledge search/exchange process, and thus have an impact upon the network building strategies of the firms. The results also reveal that sector-based technological regimes have a greater explanatory capacity than firm-based regimes that cross sectoral boundaries. The use of different approaches and techniques, together with the combination of sector and firm level analyses, provided a tool that enabled a deeper understanding of the variety of networking behaviours among knowledge-intensive firms.POCI/ESC/60500/2004 e PPCDT/ESC/60500/2004 FC

    Tetracapsuloides bryosalmonae abundance in river water

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    The file attached is the Accepted/final draft post-refereeing version of the article

    Autologous fat grafting: Harvesting techniques

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    Autologous fat grafting is widely used for soft-tissue augmentation and replacement in reconstructive and aesthetic surgery providing a biocompatible, natural and inexpensive method. Multiple approaches have been developed in the past years, varying in the location of adipose tissue donor-sites, use of wetting solutions, harvesting, processing and placing techniques. Despite many advances in this subject, the lack of standardization in the protocols and the unpredictability of the resorption of the grafted tissue pose a significant limitation for graft retention and subsequent filling. In this review, we discuss several approaches and methods described over the last years concerning the harvesting of autologous fat grafts. We focus on contents such as the best donor-site, differences between existing harvesting techniques (namely tissue resection, hand aspiration or liposuction techniques), recommended harvesting cannula diameters, pressure application and volume of wetting solution injected prior aspiration. Results and comparisons between methods tend to vary according to the outcome measured, thus posing a limitation to pinpoint the most efficient methods to apply in fat grafting. Additionally, the lack of a standard assay to determine viability or volume augmentation of fat grafting remains another limitation to obtain universally accepted grafting procedures and protocols.This work was supported by FEDER – Fundo Europeu de Desenvolvimento Regional, through NORTE 2020 Programa Operacional Regional do Norte - NORTE-01-0145-FEDER-000012 and Instituto de Investigação e Inovação em Saúde (Projeto Estratégico UID/BIM/04293/2013 )

    Trilhas ecológicas: metodologias e ferramentas de comunicação para a educação ambiental.

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    Seletividade e eficácia de herbicidas para cultura do feijão-caupi.

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    O feijão-caupi é cultivado principalmente por agricultores familiares, com adoção de baixo nível tecnológico, onde o manejo de plantas daninhas é realizado com capinas, sendo cansativa e com baixo rendimento operacional. O objetivo deste trabalho foi avaliar a seletividade de herbicidas e a eficácia de controle de plantas daninhas na cultura do feijão-caupi, variedade BRS Guariba

    Agronomic performance of eight corn genotypes in two sowing periods.

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    Os fatores climáticos de uma região determinam os períodos críticos de desenvolvimento da cultura do milho e afetam o planejamento da semeadura de forma a reduzir os efeitos negativos sobre a produtividade. Assim, objetivou-se com este trabalho avaliar o desempenho agronômico de oito genótipos de milho e duas épocas de semeadura nas condições edafoclimáticas de Manaus, Amazonas.Título em Português: Desempenho agronômico de genótipos de milho em duas épocas de semeadura
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