A Conversation with George G. Roussas

George G. Roussas was born in the city of Marmara in central Greece, on June 29, 1933. He received a B.A. with high honors in Mathematics from the University of Athens in 1956, and a Ph.D. in Statistics from the University of California, Berkeley, in 1964. In 1964--1966, he served as Assistant Professor of Mathematics at the California State University, San Jose, and he was a faculty member of the Department of Statistics at the University of Wisconsin, Madison, in 1966--1976, starting as an Assistant Professor in 1966, becoming a Professor in 1972. He was a Professor of Applied Mathematics and Director of the Laboratory of Applied Mathematics at the University of Patras, Greece, in 1972--1984. He was elected Dean of the School of Physical and Mathematical Sciences at the University of Patras in 1978, and Chancellor of the university in 1981. He served for about three years as Vice President-Academic Affairs of the then new University of Crete, Greece, in 1981--1985. In 1984, he was a Visiting Professor in the Intercollege Division of Statistics at the University of California, Davis, and he was appointed Professor, Associate Dean and Chair of the Graduate Group in Statistics in the same university in 1985; he served in the two administrative capacities in 1985--1999. He is an elected member of the International Statistical Institute since 1974, a Fellow of the Royal Statistical Society since 1975, a Fellow of the Institute of Mathematical Statistics since 1983, and a Fellow of the American Statistical Association since 1986. He served as a member of the Council of the Hellenic Mathematical Society, and as President of the Balkan Union of Mathematicians.Comment: Published in at http://dx.doi.org/10.1214/09-STS299A the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

Stretch-induced quenching in flame-vortex interactions

The flame-vortex interaction problem is a natural configuration in which several issues relevant to turbulent combustion can be addressed: effect of strain-rate and curvature, effect of the Lewis number, effect of heat losses, effect of complex chemistry, and flame-generated turbulence. In such an approach, the interaction of an isolated vortex with a laminar premixed flame is viewed as a unit process of a turbulent premixed flame in which the reaction zone keeps a laminar like structure locally; this is precisely the case of the wrinkled flame or flamelet regime in turbulent combustion. The present work complements previous studies and involves the study of the interaction of a vortex pair and a laminar premixed flame in a planar two-dimensional geometry, together with numerical simulations. This geometry is quite unique since most studies have considered axisymmetric vortex rings. Such a geometry offers several advantages over previous studies

Development of organic fertilizers from food market waste and urban gardening by composting in Ecuador

Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents.Peer ReviewedPostprint (published version

La promoción de la actividad física relacionada con la salud: la perspectiva de proceso y de resultado

La concepción de la promoción de la actividad física relacionada con la salud varía en función de la perspectiva de análisis que se adopte de sus componentes. Desde una perspectiva de resultado se pone el énfasis en las variables objetivas de las que dependen las adaptaciones orgánicas que pueden prevenir o curar enfermedades. Desde una perspectiva de proceso, los beneficios de la actividad física para la salud se relacionan fundamentalmente con aspectos cualitativos vinculados con la práctica en sí misma. Ambas perspectivas son analizadas en este artículo concluyéndose que el creciente interés por la práctica contrasta con la ausencia de orientaciones que permitan promover la actividad física relacionada con la salu

Traveling Material↔Semiotic Environments of Disability, Rehabilitation, and Physical Activity

In this article, we apply narrative dialogism and new materialism to health research. We examine how material↔semiotic environments (MSEs) affect the rehabilitation process of Patrick, a man who exercised with the aim to recover from spinal cord injury. The MSEs are considered embedded subcases within the overall holistic case of Patrick. Three MSEs were identified: the hospital gym, the personal gym, and the adapted gym. These are examined using the analytical lens of assemblages. First, the mutually affecting components of each MSE are described. Second, a larger environmental assemblage is identified, which is termed exercise-is-restitution assemblage. This composite assemblage illuminates the associations between the three MSEs, and reveals how restitution resonated across time and space. The article contributes to the literature by reconceptualizing restitution. It highlights the importance of the materiality of health-related narratives, and it reveals the potential of MSE for transforming rehabilitation and improving exercise promotion and maintenance

Demography, urbanization and natural resources in Latin America and the Caribbean: trends and forecasts

Forecasts trends in population and agriculture, with a particular focus on Latin America and the Caribbean, and discusses adaptations necessary to deal with climate chang

Estimation of a Monotone Mean Residual Life

In survival analysis and in the analysis of life tables an important biometric function of interest is the life expectancy at age x,M(x), defined by M(x)=E[X?x|X\u3ex], where X is a lifetime. M is called the mean residual life function. In many applications it is reasonable to assume that M is decreasing (DMRL) or increasing (IMRL); we write decreasing (increasing) for nonincreasing (non-decreasing). There is some literature on empirical estimators of M and their properties. Although tests for a monotone M are discussed in the literature, we are not aware of any estimators of M under these order restrictions. In this paper we initiate a study of such estimation. Our projection type estimators are shown to be strongly uniformly consistent on compact intervals, and they are shown to be asymptotically root-n equivalent in probability to the (unrestricted) empirical estimator when M is strictly monotone. Thus the monotonicity is obtained free of charge , at least in the aymptotic sense. We also consider the nonparametric maximum likelihood estimators. They do not exist for the IMRL case. They do exist for the DMRL case, but we have found the solutions to be too complex to be evaluated efficiently

Estudio biométrico de las especies del género Homalia (Neckeraceae, Musci) presentes en la Península Ibérica e Islas Canarias.

CUBERO J. I., MARCOS-SAMANIEGO N. & ENROTH J. 2001. Estudio biométrico de las especies del género Homalia (Neckeraceae, Musci) presentes en la Península Ibérica e Islas Canarias. Bot. Complutensis 25: 213-219. El género Homalia Brid. está representado en la Península Ibérica e Islas Canarias por 3 especies: H. trichomanoides, H. lusitanica y H. webbiana. Tradicionalmente su determinación se ha basado en la dentición del filidio y la longitud del nervio. En este trabajo se ha realizado un estudio biométrico de los filidios de estas especies para cuantificar sus diferencias. Se ha comprobado que la dentición del filidio es el mejor caracter para su determinación.CUBERO J. I., MARCOS-SAMANIEGO N. & ENROTH J. 2001. Biometric study on the Homalia species (Neckeraceae, Musci) occuring in the Iberian Peninsula and the Canary Islands. Bot. Complutensis 25: 213-219. There are three species of Homalia Brid. in the Iberian Peninsula and Canary Islands: H. trichomanoides, H. lusitanica and H. webbiana. Previous studies on these species have emphasized the leaf dentation and the length of the costa. For this project we carried out a biometric study of the leaves in order to pinpoint their differences. Leaf dentation is the most useful character to separate the species