The relation between post-shock temperature, cosmic-ray pressure and cosmic-ray escape for non-relativistic shocks

Supernova remnants are thought to be the dominant source of Galactic cosmic rays. This requires that at least 5% of the available energy is transferred to cosmic rays, implying a high cosmic-ray pressure downstream of supernova remnant shocks. Recently, it has been shown that the downstream temperature in some remnants is low compared to the measured shock velocities, implying that additional pressure support by accelerated particles is present. Here we use a two-fluid thermodynamic approach to derive the relation between post-shock fractional cosmic-ray pressure and post-shock temperature, assuming no additional heating beyond adiabatic heating in the shock precursor and with all non-adiabatic heating occurring at the subshock. The derived relations show that a high fractional cosmic-ray pressure is only possible, if a substantial fraction of the incoming energy flux escapes from the system. Recently a shock velocity and a downstream proton temperature were measured for a shock in the supernova remnant RCW 86. We apply the two-fluid solutions to these measurements and find that the the downstream fractional cosmic-ray pressure is at least 50% with a cosmic-ray energy flux escape of at least 20%. In general, in order to have 5% of the supernova energy go into accelerating cosmic rays, on average the post-shock cosmic-ray pressure needs to be 30% for an effective cosmic-ray adiabatic index of 4/3.Comment: 9 pages, 6 color figures. This is updated with a corrected figure 5a and 5b, reflecting an ApJ erratu

Mentoring Entrepreneurial Networks : mapping conceptions of participants in technological-based business incubators in Brazil

La agenda de la investigación reciente sobre emprendedores incluye el análisis de las estructuras cognitivas de los empresarios de éxito, revelándose como una herramienta importante a la hora de examinar una trayectoria emprendedora. Mediante técnicas de mapas cognitivos, este estudio explora los conceptos de una trayectoria de éxito y la red en sí misma como un todo, para el desarrollo de esta carrera. Fueron estudiados 53 empresarios en siete viveros tecnológicos de la ciudad de Recife, Pernambuco, Brasil. El objetivo específico de este estudio era situar los significados comunes de los emprendedores del vivero teniendo en cuenta las redes de apoyo informal. Este tipo de redes ofrecen apoyo a la carrera empresarial, y el presente estudio examina tanto las características como el modelo conceptual que subyace bajo éstas. La recolección de datos fue realizada por medio de entrevistas a través de la técnica de evocación libre. Los significados comunes indican la existencia de categorías de pensamiento inherentes que fomentan el contexto de la red en el entorno del vivero, especialmente en las redes-mentor. Los resultados refuerzan la interpretación de un modelo mentor informal que emerge de las evocaciones predominantes respecto a una carrera de éxito y de la red en sí misma como promotora de su desarrollo.The recent entrepreneurship research agenda includes the analysis of cognitive structures of successful entrepreneurs, revealing an important tool for the examination of an entrepreneurial career. Using techniques of cognitive maps, this study explores the concepts of a successful career and the network itself, as a whole, for career development. Fifty-three entrepreneurs were studied, in seven technological incubators in the city of Recife, Pernambuco, Brazil. Specifically, this study aimed to map the shared meanings of the incubated entrepreneurs regarding informal support networks. Such networks support the entrepreneurial career and the present study explores the characteristics and the conceptual model that underlies the networks. The data collection was achieved through interviews through a free evocation technique. The shared meanings indicate the existence of inherent thought categories that support network context in the incubator environment, mainly the mentoring networks. The results endorse the interpretation of an informal mentoring model emerging from the dominant evocations concerning a successful career and of the network itself as promoter of career development

Occupational exposure to welding fumes in the metalo-mechanic industries in Portugal

Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2016 do Instituto Politécnico de Lisboa. Código de referência: IPL/2016/CEPPS_ESTeSLSome studies on occupational exposure to particulate have pointed out to hazardous effects to workers, in what regards inhalable and also respirable particulate. These occupational exposure scenarios are extremely complex as they involve components inherent to the individuals, working conditions and the developed activity itself. This requires the application of an integrated approach comprising diagnostic, evaluation and risk management, adapted to each specific situation. Regarding welding processes, several authors have shown the existence of asthma prevalence four-time higher in welders in the USA than in other population. Exposure to a specific type of welding depends on several factors such as the location of ventilation and exhaust equipment, the air flux, the amount of generated fumes, the workplace area, the distance from the welding front and the welding practices themselves. Bearing in mind these considerations, the following research question arises: which is the occupational exposure to welding fumes in the metalo-mechanic industries in Portugal? This work aims to perform a characterization and environmental evaluation in a specific situation: welding processes in the metalo-mechanic industry, and identify eventual alterations on workers’ health.info:eu-repo/semantics/publishedVersio

Pattern design methods for non-conventional bodies

The main goal of the study presented in this paper was to compare three different methodologies of pattern design methods. The case study was based on an individual body shape with a severe deformity in the spine with additional different measurements of the bust, waist and hip girths when compared with common standard measurement tables. This methodology comparison aims primarily to identify its performance regarding garment Fit and performance, in particularly, its potential related to electronic sensor integration for vital signals monitoring. Different performance results were obtained, with the best results obtained with the flat pattern block extracted from the 3D digital model surface methodology, followed by the flat pattern block using the studied individual personal measurements and the worst results obtained with the flat pattern block developed from a typical measurements table used by the industry and fashion schools.This work is financed by Project “Deus ex Machina”, NORTE-01-0145-FEDER-000026, funded by CCDRN, through Sistema de Apoio à Investigação Cientifica e Tecnológica (Projetos Estruturados I&D&I) of Programa Operacional Regional do Norte, from Portugal 2020 and by FEDER funds through the Competitive Factors Operational Program (COMPETE) POCI-01-0145-FEDER-007136 and by national funds through FCT-Portuguese Foundation for Science and Technology, under the project UID/CTM/000264.info:eu-repo/semantics/publishedVersio

An Assessment of Human Resource Development Program in Mozambique's Public Extension Service

Although Mozambique independent in 1975, public agricultural extension was not established until 1987, through the institutionalization of the National Directorate of Rural Development (DNDR). Since its establishment, human resource development has been a priority. Two approaches have been adopted by DNER for the improvement of human resource over time: the first was in-service training (non- formal and formal); and the second was to replace the elementary and certificate extensionists by hiring diploma technicians on contracts. Three evolutionary periods characterize the development of public extension in Mozambique: the establishment phase (1987-1992), the expansion stage (1993-1997), and the unified extension and PROAGRI phase (1998-2004). During each of these three phases DNER has pursued human resource development. Over the period of unified extension and PROAGRI from 1998 to 2004, DNER introduced a number of challenging goals for improving the quality of its human resources. This study was undertaken to evaluate DNER’s accomplishments in human resource development. The study addressed the role of in-service training in strengthening human resources through the acquisition of new knowledge, skills and the development of critical (analytical) thinking. This study covers only the public extension services. The data were collected during January to October 2004. Several sources of information were consulted and a questionnaire was used to collect information from DN ER staff members. The survey was carried out in January and February 2004 in 33 districts of the 66 in which public extension is currently operating. A total of 260 extensionists and supervisors were interviewed out of a total of 664 field staff members. Although human resource development and in-service training are a continuous and dynamic process, this evaluation is an overall assessment of DNER’s human resource program. The study addresses training effectiveness and relevance based on the principal courses offered to the staff over time, especially during the 1999-2004 Extension Master Plan. The results of the study show that DNER achieved impressive results in the acquisition (hiring diploma staff members on contract) of new staff but the challenging goal to have in place only diplomas as frontline extension workers by 2004 was not accomplished. The upgrading plans (1999-2004) were partially accomplished but the plan of upgrading 138 certificate extensionists to diploma level was far below expectations while results on diploma and BSc upgrading were encouraging. Low participation in-service training by staff members is also troubling. Because 35% of the sampled extensionists are still from secondary schools, special attention must be given to upgrading the knowledge and skills of those agents. One of the most important findings of the survey was the general lack of knowledge of technical messages on land preparation, soil erosion and use of fertilizers, weeding, crop pests and diseases, livestock health information and emerging issues such as irrigation, processing and marketing. Basic information needs to be collected by agricultural economists on the economics of complex interventions such as the use of treadle pumps, conservation farming and processing. Attention should be given to upgrading the technical knowledge and skills of extension staff at all levels.Dissertation (MSc)--University of Pretoria, 2007.Agricultural Economics, Extension and Rural Developmentunrestricte