1,267 research outputs found

    Ways to open innovation: main agents and sources in the Portuguese case

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    Facing increasing open innovation trends, Portuguese enterprises are considering the related processes and impacts. Thus, this work aims to identify the sectors whose enterprises most engage in open innovation (such as cooperation on this issue) and which sources/agents are most used. This is analyzed by sector and type of innovation as an interesting way of differentiation for better open innovation strategy delineation. Using the data from the Community Innovation Survey (CIS-2012), it first appraises the nature of the innovation process, either cooperative or firm-based, as the starting level of analysis. Then, it differentiates the results by sector illustrating which cooperation sources/agents are most used (scope) and relative intensity of use (scale). This is important to assess levels of openness and related factors. Results show that main innovating sectors in Portugal are of three types: research-based, knowledge-based and service-based. They reveal an increasing focus on knowledge and services, trends that have been leading to more active openness towards innovation. For instance, health and construction are increasing their openness for innovating and internationalizing processes. However, Portuguese innovation is still more firm-based (in-house) than cooperation-based, especially concerning new products' launching. This work and future analyzes around it can contribute to encourage the open innovation strategy in more sectors of the economy as an easy and effective way to cope with rapid trends and changes. (C) 2017 Elsevier Ltd. All rights reserved.info:eu-repo/semantics/publishedVersio

    Aspects of Two-Level Systems under External Time Dependent Fields

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    The dynamics of two-level systems in time-dependent backgrounds is under consideration. We present some new exact solutions in special backgrounds decaying in time. On the other hand, following ideas of Feynman, Vernon and Hellwarth, we discuss in detail the possibility to reduce the quantum dynamics to a classical Hamiltonian system. This, in particular, opens the possibility to directly apply powerful methods of classical mechanics (e.g. KAM methods) to study the quantum system. Following such an approach, we draw conclusions of relevance for ``quantum chaos'' when the external background is periodic or quasi-periodic in time.Comment: To appear in J. Phys. A. Mathematical and Genera

    Multiple classical limits in relativistic and nonrelativistic quantum mechanics

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    The existence of a classical limit describing interacting particles in a second-quantized theory of identical particles with bosonic symmetry is proved. This limit exists in addition to a previously established classical limit with a classical field behavior, showing that the limit 0\hbar \to 0 of the theory is not unique. An analogous result is valid for a free massive scalar field: two distinct classical limits are proved to exist, describing a system of particles or a classical field. The introduction of local operators in order to represent kinematical properties of interest is shown to break the permutation symmetry under some localizability conditions, allowing the study of individual particle properties.Comment: 13 page

    Comparative phylogeography of northwest African Natrix maura (Serpentes: Colubridae) inferred from mtDNA sequences

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    While the comparative phylogeography of European fauna is relatively well understood, with Pleistocene climatic oscillations leading to ‘southern refugia’ for many species, the equivalent pattern has not been determined for North Africa. In this context variation within North African populations of the riverine snake Natrix maura were assessed using mitochondrial DNA sequences. Recent literature regarding North African phylogeographic studies of reptiles was compiled, and several surprising patterns emerged. The most interesting was the extensive movement of species across the Strait of Gibraltar during the Pleistocene. Another is the general pattern of deep genetic divergences between Tunisian and Moroccan populations, often at a level implying the existence of cryptic species. Natrix maura has three distinct lineages in North Africa, however, it apparently did not cross the Strait of Gibraltar during the Pleistocene, but probably did so during the Messinian salinity crisis

    Process quality in Portuguese preschool classrooms serving children at-risk of poverty and social exclusion and children with disabilities

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    This study investigates process quality and structural features of classrooms serving children at-risk of poverty and social exclusion and children with disabilities in Portugal. We examine (a) whether the three-domain structure of a widely used standard observational tool, the Classroom Assessment Scoring System (CLASS; Pianta, LaParo, & Hamre, 2008) describes adequately teacher–child interactions in those classrooms and (b) associations between CLASS domains and structural features, including teacher education and group size. The study was conducted in 178 preschool classrooms. Data included classroom observations using the CLASS Pre-K and teacher reports on structural features. Confirmatory factor analysis supported the three domains of teacher–child interactions. In addition, the CLASS domains described teacher–child interactions equally well across classrooms serving children with disabilities and children at-risk of poverty and social exclusion. Finally, we found modest associations between structural features and CLASS organizational and instructional support, suggesting a complex interplay among structural features in predicting levels of teacher–child interactions.info:eu-repo/semantics/acceptedVersio

    Hematoma Subdural em Pediatria Diagnosticar e Tratar Precocemente

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    Introdução: O hematoma subdural agudo não traumático é uma entidade rara em Pediatria. A presença de sintomas neurológicos de instalação aguda associada a anti coagulação obriga à exclusão desta entidade. Caso clínico: Apresentamos o caso de uma criança, do sexo masculino, de sete anos de idade, com prótese mitral mecânica, medicada com varfarina, que recorreu ao serviço de urgência por cefaleias intensas e progressivas, associadas a alteração no estado de consciência e convulsões. A nível laboratorial o INR (International Normalized Ratio) era de 4,2. Foi admitida na Unidade de Cuidados Intensivos Pediátricos (UCIP) em coma com anisocoria. Iniciou ventilação mecânica, medidas anti-edema cerebral e antiepilépticos. O exame de imagem mostrou hematoma subdural agudo à esquerda, com desvio da linha média. Foi submetida a craniotomia descompressiva, 56 horas após o início da sintomatologia, com recuperação clínica e actualmente sem sequelas. Conclusão: Este caso clínico ilustra a importância da suspeição clínica de hematoma subdural em doentes anti coagulados, bem como a necessidade de optimização das condições cirúrgicas e da utilização das técnicas não invasivas na monitorização do nível de consciência

    Existence of the Bogoliubov S(g) operator for the (:ϕ4:)2(:\phi^4:)_2 quantum field theory

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    We prove the existence of the Bogoliubov S(g) operator for the (:ϕ4:)2(:\phi^4:)_2 quantum field theory for coupling functions gg of compact support in space and time. The construction is nonperturbative and relies on a theorem of Kisy\'nski. It implies almost automatically the properties of unitarity and causality for disjoint supports in the time variable.Comment: LaTeX, 24 pages, minor modifications, typos correcte
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