The process of opening innovation networks: open innovation at Embrapa Florestas

Purpose – The purpose of this paper is to map the process of opening an innovation network in the context of the Brazilian agroforestry sector. Design/methodology/approach – Qualitative case study of the open innovation network Embrapa Florestas (17 semi-structured interviews, observation and documentary data). Social network analysis (SNA) of the open innovation network from primary data is available at Embrapa Florestas’ system. Findings – Three primary triggers to the opening process of Embrapa Florestas’ innovation network were identified. The process starts with an innovation network with closed network characteristics. The process of opening the innovation network is motivated by a restructuring in its source of fundraising (trigger 1), by the change in strategic orientation toward the internationalization of its network activities (trigger 2) and by opening the black box of its innovation with greater proximity to the productive sector and partner universities (trigger 3). Comparing the pre-opening and post-opening networks (open innovation network), sociometric data allows us to verify that the opening of the innovation network presents better density, clustering and centrality indexes for the network as a whole and for the Embrapa Florestas specifically. Originality/value – This is one of the first studies that aims to investigate the transition from a closed innovation network to an open innovation network by a public research institute. It may also be considered innovative because it presents practical and managerial relevance – in addition to contributions to public policy makers – which allows for improvements in the development of innovation and technology in the country’s strategic sectors

The dynamics of financial stability in complex networks

We address the problem of banking system resilience by applying off-equilibrium statistical physics to a system of particles, representing the economic agents, modelled according to the theoretical foundation of the current banking regulation, the so called Merton-Vasicek model. Economic agents are attracted to each other to exchange `economic energy', forming a network of trades. When the capital level of one economic agent drops below a minimum, the economic agent becomes insolvent. The insolvency of one single economic agent affects the economic energy of all its neighbours which thus become susceptible to insolvency, being able to trigger a chain of insolvencies (avalanche). We show that the distribution of avalanche sizes follows a power-law whose exponent depends on the minimum capital level. Furthermore, we present evidence that under an increase in the minimum capital level, large crashes will be avoided only if one assumes that agents will accept a drop in business levels, while keeping their trading attitudes and policies unchanged. The alternative assumption, that agents will try to restore their business levels, may lead to the unexpected consequence that large crises occur with higher probability

Role of magnetic anisotropy on the magnetic properties of Ni nanoclusters embedded in a ZnO matrix

We have investigated the magnetic properties of Ni nanoaggregates produced by ion implantation in ZnO single crystals. Several deviations from classical models usually adopted to describe the magnetic properties of nanoparticle systems were found. The strain between host and Ni nanoaggregates induces a magnetic anisotropy with a preferred direction. We show that these anisotropy effects can be misinterpreted as a ferromagnetic or antiferromagnetic coupling among the nanoaggregates similar to that of an oriented, interacting nanocrystal ensemble

Quantum dilaton gravity as a linear dilaton conformal field theory

A model of matter-coupled gravity in two dimensions is quantized. The crucial requirement for performing the quantization is the vanishing of the conformal anomaly, which is achieved by tuning a parameter in the interaction potential. The spectrum of the theory is determined by mapping the model first onto a field theory with a Liouville interaction, then onto a linear dilaton conformal field theory. In absence of matter fields a pure gauge theory with massless ground state is found; otherwise it is possible to minimally couple up to 11 matter scalar fields: in this case the ground state is tachyonic and the matter sector decouples, like the transverse oscillators in the critical bosonic string.Comment: 7 pages, RevTeX4 file. v2: some comments and one reference adde

Two-dimensional quantum-corrected black hole in a finite size cavity

We consider the gravitation-dilaton theory (not necessarily exactly solvable), whose potentials represent a generic linear combination of an exponential and linear functions of the dilaton. A black hole, arising in such theories, is supposed to be enclosed in a cavity, where it attains thermal equilibrium, whereas outside the cavity the field is in the Boulware state. We calculate quantum corrections to the Hawking temperature $T_{H}$, with the contribution from the boundary taken into account. Vacuum polarization outside the shell tend to cool the system. We find that, for the shell to be in the thermal equilibrium, it cannot be placed too close to the horizon. The quantum corrections to the mass due to vacuum polarization vanish in spite of non-zero quantum stresses. We discuss also the canonical boundary conditions and show that accounting for the finiteness of the system plays a crucial role in some theories (e.g., CGHS), where it enables to define the stable canonical ensemble, whereas consideration in an infinite space would predict instability.Comment: 21 pages. In v.2 misprints corrected. To appear in Phys. Rev.

An analysis of the sensitivity and specificity of MHC-I and MHC-II immunohistochemical staining in muscle biopsies for the diagnosis of inflammatory myopathies

Although there have been several previous reports of immunohistochemical staining for MHC antigens in muscle biopsies, there appears to be a lack of consensus about its routine use in the diagnostic evaluation of biopsies from patients with suspected inflammatory myopathy. Positive MHC-I staining is nonspecific but is widely used as a marker for inflammatory myopathy, whilst the role of MHC-II staining is not clearly defined. We investigated the sensitivity and specificity of MHC-I and MHC-II immunostaining for the diagnosis of inflammatory myopathy in a large group of biopsies from a single reference laboratory. Positive staining for MHC-I was found to have a high sensitivity in biopsies from patients with inflammatory myopathy but a very low specificity, as it was also common in other non-inflammatory myopathies and neurogenic disorders. On the other hand, MHC-II positivity had a much higher specificity in all major subgroups of inflammatory myopathy, especially inclusion body myositis. The findings indicate that the combination of MHC-I and MHC-II staining results in a higher degree of specificity for the diagnosis of inflammatory myopathy and that in biopsies with inflammation, positive MHC-II staining strongly supports the diagnosis of an immune-mediated myopathy. We recommend that immunohistochemical staining for both MHC-I and MHC-II should be included routinely in the diagnostic evaluation of muscle biopsies from patients with suspected inflammatory myopathy. However, as the sensitivity and interpretation of MHC staining may depend on the technique used, further studies are needed to compare procedures in different centres and develop standardised protocols

Time evolution of damage under variable ranges of load transfer

We study the time evolution of damage in a fiber bundle model in which the range of interaction of fibers varies through an adjustable stress transfer function recently introduced. We find that the lifetime of the material exhibits a crossover from mean field to short range behavior as in the static case. Numerical calculations showed that the value at which the transition takes place depends on the system's disorder. Finally, we have performed a microscopic analysis of the failure process. Our results confirm that the growth dynamics of the largest crack is radically different in the two limiting regimes of load transfer during the first stages of breaking.Comment: 8 pages, 7 figures, revtex4 styl

The superconductivity at 18 K in LiFeAs system

A new iron arsenide superconducting system LiFeAs was found that crystallizes into a tetragonal structure with space group P4/nmm. The superconductivity with Tc up to 18 K was observed in the compounds. This simple 111 type layered iron arsenide superconductor can be viewed as an analogue of the infinite layer structure of copper oxides.Comment: 11 pages 3 Figure

Local Void vs Dark Energy: Confrontation with WMAP and Type Ia Supernovae

It is now a known fact that if we happen to be living in the middle of a large underdense region, then we will observe an "apparent acceleration", even when any form of dark energy is absent. In this paper, we present a "Minimal Void" scenario, i.e. a "void" with minimal underdensity contrast (of about -0.4) and radius (~ 200-250 Mpc/h) that can, not only explain the supernovae data, but also be consistent with the 3-yr WMAP data. We also discuss consistency of our model with various other measurements such as Big Bang Nucleosynthesis, Baryon Acoustic Oscillations and local measurements of the Hubble parameter, and also point out possible observable signatures.Comment: Minor numerical errors and typos corrected, references adde

La aplicación combinada de abonos orgánicos mejora las propiedades físicas del suelo asociado al cultivo de quinua (Chenopodium quinoa Willd.)

The reduced acceleration of the organic matter in the soil has been affecting its properties, making it necessary to repeat the use and management of organic fertilizers. The objective of research was to evaluate the effect of two fertilizers application, Island Guano (IG) and sheep manure (SM), on the following three physical properties of the soil: bulk density, water-stable aggregates and penetration resistance, under quinoa (Chenopodium quinoa Willd) cultivation, Hualhuas variety. These properties were determined by beveled cylinder, Yoder wet-sieving and dynamic cone penetrometer methods and under a completely randomized block design, with factorial arrangement of two factors (IG and SM) and three levels per factor (0; 0.5 and 1 t*ha-1 for IG and 0; 2.5 and 5 t*ha-1 for SM), nine treatments were evaluated, with three repetitions, so 27 total experimental units. Results showed that combined application of different doses of IG and SM does not influence bulk density, but with doses IG 0,5 t*ha-1 with SM 5 t*ha-1 and IG 1 t*ha-1 with SM 5 t*ha-1 water-stable aggregates and penetration resistance improved significantly.La acelerada disminución de la materia orgánica del suelo viene afectando sus propiedades, siendo necesario reincidir en el uso y manejo de abonos orgánicos. El objetivo del presente trabajo fue evaluar el efecto de la aplicación de dos abonos orgánicos combinados, Guano de las Islas (GI) y estiércol de ovino (EO), sobre las siguientes tres propiedades físicas del suelo: densidad aparente, estabilidad de agregados y resistencia mecánica a la penetración, bajo el cultivo de quinua (Chenopodium quinoa Willd) variedad Hualhuas. Estas propiedades se determinaron mediante los métodos de cilindro biselado, Yoder y del penetrómetro dinámico y bajo un diseño en bloques completamente al azar, con arreglo factorial de dos factores (GI y EO) y tres niveles por factor (0; 0,5 y 1 t/hapara GI y 0; 2,5 y 5 t/hapara EO). Los resultados demostraron que la aplicación combinada de las diferentes dosis en estudio no influye sobre la densidad aparente del suelo, pero la aplicación combinada de 0,5 t/ha de GI con 5 t/ha de EO y 1 t/ha de GI con 5 t/hade EO disminuyen significativamente la resistencia mecánica del suelo a la penetración e incrementan la estabilidad de agregados