Filamentation processes and dynamical excitation of light condensates in optical media with competing nonlinearities

We analyze both theoretically and by means of numerical simulations the phenomena of filamentation and dynamical formation of self-guided nonlinear waves in media featuring competing cubic and quintic nonlinearities. We provide a theoretical description of recent experiments in terms of a linear stability analysis supported with simulations, showing the possibility of experimental observation of the modulational instability suppression of intense light pulses travelling across such nonlinear media. We also show a novel mechanism of indirect excitation of {\em light condensates} by means of coalescence processes of nonlinear coherent structures produced by managed filamentation of high power laser beams.Comment: 6 pages, 4 figure

Nanocarriers based on interpolyelectrolyte complexation of Sulphated polysaccharide-b- PEG diblock copolymers and PLL

Publicado em "Journal of Tissue Engeneering and Regenerative Medicine", vol. 7, supp. 1 (2013)Glycosaminoglycans (GAGs) are integral part of the closest cellular environment: they can be found on the cells surface and in the extracellular matrix, where they interact with different proteins acting as local regulator of their activity. The use of GAGs in the preparation of protein delivery nanosystems is, therefore, prominent but so far, underexploited mainly because of the heterogeneity (composition and molecular weights) of natural glycans and the multistep procedures needed to obtain GAGs’ synthetic analogues and diblock copolymers.1 Recently, we have shown that oxime click reaction can be applied as a straightforward methodology for the synthesis of poly(ethylene glycol) (PEG)- hyaluronic acid (HA) diblock copolymers.2 These copolymers formed nanosized interpolyelectrolyte complexes (45 to 150 nm) by interaction with poly- L -lysine (PLL).3 Unfortunately, these complexes are not stable at physiological ionic strength. Herein, we describe a strategy to overcome this drawback; chondroitin sulphate-b-PEG diblock copolymers (CS-b-PEG) were obtained using the same oxime click reaction. The stronger negative charge of sulphate groups (versus the carboxilic groups present in HA) resulted in the complexes with higher stability: interpolyelectrolyte complexes between PLL and (CS-b-PEG) are stable up to 260 mM ionic strenght. Because carbohydrates do not activate Tcells, we believe that the reported herein complexes have an enormous potential in both drug delivery and vaccination fields

Estudio experimental de la extracción de carragenano a partir del alga Iridaea laminarioides

El objetivo de este trabajo fue hacer un estudio de factibilidad técnica de un proceso de extracción de carragenano a partir del alga roja Iridaea laminarioides, considerando que la recolección nacional de algas productoras de este polisacárido bordea las 3.000 Ton/año. Se estableció la influencia que tienen sobre el rendimiento y la calidad del producto obtenido, las variables siguientes: tiempo de extracción, relación volumen de solvente de extracción a masa de alga seca, volumen del agente precipitante, tiempo y velocidad de centrifugación, decoloración, etc. El proceso estudiado proporciona un producto blanco, de viscosidad promedio igual a 50 cp para soluciones al 1% en peso a 25°C y que forma geles fuertes cuando se lo trata con hidróxido de potasio. El rendimiento de producto es 70% y corresponde aproximadamente al 400 /o de la masa inicial de alga seca (19% humedad base seca)

Effects of Urbanization and Other Factors on Synthetic Unit Hydrographs

Paper by Albert H. Halff, Jose I. Novoa, and Louis M. Salced

Valoración económica del patrimonio natural: las áreas naturales protegidas

Economic Valuation of the natural patrimony: Protected Natural Areas This paper offers some knowledge about the utility of Economic Valuation of Assets out of  market methods, to allow management in general and as a guide to the planning of natural areas with valuable ecologic and landscaping aspects. Here, I show the importance of the Protected Natural Areas (ANP) in the national economy and their economic value. I describe the most used techniques in the valuation of ANPs with special attention to the direct using values through the application of cost of travel and contingent valuation methods. As an example of the use of these techniques, I present the application results at the Private Conservation Area-El Cañoncillo Natural Forest, with the objective to analyze the pertinence of the economic valuation by the adoption of conservation practices

Invirtiendo en capital natural: un marco para integrar la sostenibilidad ambiental en las políticas de cooperación

Tomando en cuenta la magnitud de la crisis ambiental que afecta al planeta y los estrechos vínculos existentes entre la conservación de los ecosistemas y la lucha contra la pobreza, cabría preguntarse por qué los temas de protección del medio ambiente continúan teniendo un peso relativo tan bajo en las agendas y prioridades de las agencias de cooperación internacional. En este artículo, se analizan las razones de este desequilibrio y se propone un marco conceptual con base socio-ecológica para facilitar una verdadera integración de la sostenibilidad ambiental como prioridad estratégica en las políticas y herramientas de ayuda oficial al desarrollo. Varios paradigmas y principios fundamentales emanan de este nuevo marco conceptual, que considera a los ecosistemas funcionales como un capital natural que, adecuadamente gestionado, es capaz de producir un rico y variado flujo de servicios sobre los cuales es posible construir un proceso de desarrollo social, económica y ambientalmente sostenible, además de justo en términos de equidad intra e intergeneracional

TACTICAL BLOCKCHAIN TO PROVIDE DATA PROVENANCE IN SUPPORT OF INTERNET OF BATTLEFIELD THINGS AND BIG DATA ANALYTICS

This capstone project evaluated the use of blockchain technology to address a number of challenges with increasing amounts of disparate sensor data and an information-rich landscape that can quickly overwhelm effective decision-making processes. The team explored how blockchain can be used in a variety of defense applications to verify users, validate sensor data fed into artificial intelligence models, limit access to data, and provide an audit trail across the data life cycle. The team developed a conceptual design for implementing blockchain for tactical data, artificial intelligence, and machine learning applications; identified challenges and limitations involved in implementing blockchain for the tactical domain; described the benefits of blockchain for these various applications; and evaluated this project’s findings to propose future research into a wider set of blockchain applications. The team did this through the development of three use cases. One use case demonstrated the use of blockchain at the tactical edge in a “data light” information environment. The second use case explored the use of blockchain in securing medical information in the electronic health record. The third use case studied blockchain’s application in the use of multiple sensors collecting data for chemical weapons defense to support measurement and signature intelligence analysis using artificial intelligence and machine learning.Civilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyApproved for public release. Distribution is unlimited