Phaeocryptopus gaeumannii, patógeno causante del "swiss needle cast" en Pseudotsuga menziesii: antecedentes de su biología, medidas de control y situación en Chile SUMMARYSwiss needle cast is a disease caused by Phaeocryptopus gaeumannii, a fungal pathogen causing severe defoliation in Pseudotsuga menziesii (Douglas fir) in some countries of the world, leading to losses in the volume of timber harvesting. This pathogen is distributed in the native range of P. menziesii in North America (U.S., Canada and Mexico) and has been introduced in Europe, New Zealand, Turkey and, recently, in Chile. Currently the country has an area larger than 16,000 ha of plantations of P. menziesii, which are increasing because it is a potentially productive species considered in species diversification programs. In Chile P. gaeumannii is distributed from the region of La Araucanía to Los Lagos, focusing on these areas the largest area of Douglas fir in the country (70 % approximately). The aim of this review was to examine studies related to biology and life cycle of the pathogen, epidemiology and infection processes, impact on plantations and control measures implemented in the different countries affected by this pathogen, in order to have a background take on the first studies to Chile, a referent to basic and applied research for the country. Key words: Phaeocryptopus gaeumannii, Pseudotsuga menziesii, volumetric losses timber distribution the SNC in Chile. RESUMENEl swiss needle cast o pérdida suiza de las acículas, es una enfermedad de carácter fungoso provocada por el patógeno Phaeocryptopus gaeumannii, organismo que causa severas defoliaciones en Pseudotsuga menziesii (pino oregón) en el mundo, originando pérdidas en el volumen de madera para cosechar. Este patógeno se distribuye en el rango nativo de P. menziesii en América del Norte (EE.UU., Canadá y México) y se ha introducido en Europa, Nueva Zelanda, Turquía y, recientemente en Chile. Actualmente, el país cuenta con una superficie superior a las 16.000 hectáreas de plantaciones de P. menziesii, las cuales van en aumento por tratarse de una especie con potencial productivo considerada en programas de diversificación de especies. En Chile P. gaeumannii se encuentra distribuido desde las regiones de La Araucanía a Los Lagos, concentrándose en estas zonas la mayor superficie de P. menziesii del país (70 % aproximadamente). El objetivo de esta revisión fue analizar estudios relacionados a la biología y ciclo de vida del patógeno, la epidemiología y procesos de infección, impacto en las plantaciones y medidas de control implementadas en los diferentes países afectados por este patógeno, de manera de contar con antecedentes científicos para realizar los primeros estudios en Chile, referentes a investigación básica y aplicada para el país.Palabras clave: Phaeocryptopus gaeumannii, Pseudotsuga menziesii, pérdidas volumétricas de madera, distribución de SNC en Chile.

Wildfires in the Valparaíso region (Chile) account for one of the main threats to local biodiversity, ecosystem services and infrastructure. This study focused on producing an initial record of thermo- and physicochemical properties of local forest species. For this purpose, leaf samples of species found in the Peñuelas Lake National Reserve, namely Pinus radiata, Eucalyptus globulus, Acacia dealbata, Quillaja saponaria and Cryptocarya alba, were collected and analysed. Higher and lower heating value, flash point, density and moisture content tests were performed for each sample. Overall results showed that lower heating values measured for both native and exotic species could indicate a high energy release source in wildfires. However, differences in the flash point between species indicated that C. alba and E. globulus had a lower ignition resistance than other species tested, possibly due to a lower flash point. In contrast, Q. saponaria and A. dealbata had the highest flash point for native and exotic species respectively. Finally, all presented data and procedures were aimed at establishing a foundation for a national database of critical forest species properties to be used in wildfire simulation tools. This database will enhance forest fire management effectiveness in Chile.

The resolution of fluorescence microscopy images is limited by the physical properties of light. In the last decade, numerous super-resolution microscopy (SRM) approaches have been proposed to deal with such hindrance. Here we present Mean-Shift Super Resolution (MSSR), a new SRM algorithm based on the Mean Shift theory, which extends spatial resolution of single fluorescence images beyond the diffraction limit of light. MSSR works on low and high fluorophore densities, is not limited by the architecture of the optical setup and is applicable to single images as well as temporal series. The theoretical limit of spatial resolution, based on optimized real-world imaging conditions and analysis of temporal image stacks, has been measured to be 40 nm. Furthermore, MSSR has denoising capabilities that outperform other SRM approaches. Along with its wide accessibility, MSSR is a powerful, flexible, and generic tool for multidimensional and live cell imaging applications.

In this work a comparison between two algorithms for image segmentation via the mean shift is carried out. These algorithms apply recursively the mean shift filtering by using the euclidean and infinity norms in order to define pixel neighborhoods. In the conventional mean shift algorithm for image segmentation euclidean norm is used. Due to matrix representation of images and the rectangular windows used in the implementation of the algorithm, with the aim of evaluating pixels membership to neighborhoods, the use of euclidean norm always implies evaluate membership of pixels wich certainly cannot be inside each defined neighborhood. However, the use of the infinity norm ensures that each evaluated pixel could be inside the neighborhood. This fact avoids unnecessary calculations. In the work the convergence of the algorithm, by using the infinity norm, is proven. Additionaly, the runtimes of both algorithms were compared using different spatial and range bandwidth sizes. Through an extensive experimentation using standard images was evidenced that the use of the infinity norm, instead of the euclidean norm, decreases the runtime of the mean shift when the values of spatial and range bandwidths were increased.

Vehicular Ad-Hoc NETworks (VANETs), a pillar for the Internet of Vehicles, aim to improve road safety by preventing and reducing traffic accidents. While VANETs offer a great variety of safety and infotainment applications, there remain a number of security and privacy challenges, such as, user profiling and vehicle tracking, which, must be addressed. This paper contributes with a framework to address security and privacy issues in VANETs. The proposed framework consists of i) an inter-domain authentication system able to provide a near realtime certificate status service, ii) a mechanism to quantitatively evaluate the trust level of a CA and establish a on-the-fly interoperability relationship, and iii) a privacy enhancing model that addresses privacy in terms of linkability. © 2014 IEEE.Peer ReviewedPostprint (published version

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