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This paper aims to consider the influence of the temperature and of an external magnetic field on the steady oblique stagnation-point flow for a Boussinesquian nanofluid past a stretching or shrinking sheet.

The flow is reduced through similarity transformations to an ordinary boundary value problem, which is solved numerically in MATLAB using the bvp4c function. The behavior of the solution is discussed physically, and some analytical considerations concerning existence of the solution and the occurrence of dual solutions are drawn.

The study of the influence of an external magnetic field on the oblique stagnation-point flow of a Buongiorno's Boussinesquian nanofluid is carried out. The fluid clashes on a vertical stretching or shrinking sheet. Dual solutions appear for suitable values of the parameters.

The present results are new and original.

This paper aims to analyze the steady two-dimensional stagnation-point flow of an electrically conducting Newtonian or micropolar fluid when the obstacle is uniformly heated.

The governing boundary layer equations are transformed into a system of ordinary differential equations using appropriate similarity transformations. Some analytical considerations about existence and uniqueness of the solution are obtained. The system is then solved numerically using the bvp4c function in MATLAB.

If the temperature of the obstacle T_w coincides with the environment temperature T₀, then the motion reduces to the usual orthogonal stagnation-point flow; if T_w = T₀, then it is necessary to include in the similarity function describing the velocity an oblique part due to the temperature. Also, the presence of a uniform external magnetic field orthogonal to the obstacle is examined. In all cases, the motion is reduced to a system of nonlinear ordinary differential equations with boundary conditions, whose solution is discussed numerically when the Prandtl and the Hartmann number varies.

The present results are original and new for the problem of magnetohydrodynamic mixed convection in the plane stagnation-point flow of a Newtonian or a micropolar fluid over a vertical flat plate. At infinity, the motion approaches the orthogonal stagnation-point flow of an inviscid fluid; the effect of an uniform external magnetic field is considered, and the obstacle has a uniform temperature.

Cuba’s 1959 Revolution brought about dramatic changes not only in that island‐nation but also in the USA. Cubans, and later Cuban‐Americans, have changed the face of Miami and south Florida. The economic and social successes of Cuban‐Americans, the third largest Latino group in the USA, are prevalent in scholarly and popular literature. In this annotated bibliography, the author presents journal articles, chapters in books, books, and human rights reports, published between 1990 and 1998, as well as World Wide Web sites, that discuss the Cuban‐American experience. Articles from the popular literature are not included, nor are materials that deal primarily with Cuba or Cuba‐USA relations.

This article sets out to show how principles and questions about method that underlie a way of interpreting the discipline of conservation and restoration can find results in research and studies, aiming at achieving even conscious reuse process. The occasion is the very recent research performed on the former Church of Saints Gerolamo and Francesco Saverio in Genoa, Italy, the Jesuit church annexed to the 17th-century College of the order. It is a small Baroque jewel in the heart of the ancient city, former University Library and actually abandoned, forgotten for years, inaccessible and awaiting a new use.

The two-year work carried out on the monumental building was conducted according to a study and research methodology developed and refined over the years within the activities of the School of Specialisation in Architectural Heritage and Landscape of the University of Genoa. It is a multidisciplinary and rigorous approach, which aims to train high-level professionals, up-to-date and aware of the multiple problems that interventions on existing buildings, especially of a monumental nature, involve.

The biennal study has been carried out within the activities of the Post-Graduate Programme in Architectural Heritage and Landscape of the University of Genoa. The work methodology faces the challenges of the contemporary complexity, raised by the progressive broadening of the concept of cultural “heritage” and by the problems of its conservation, its active safeguard and its reuse: safety in respect of seismic risk, fire and hydro geological instability, universal accessibility – cognitive, physical and alternative – resource efficiency, comfort and savings in energy consumption, sustainability, communication and involvement of local communities and stakeholders.

The goals of the work were the following: understanding of the architectural heritage, through the correlated study of its geometries, elements and construction materials, surfaces, structures, spaces and functions; understanding of the transformations that the building has undergone over time, relating the results of historical reconstructions from indirect sources and those of direct archaeological analysis; assessment of the state of conservation of the building recognising phenomena of deterioration, damage, faults and deficits that affect materials, construction elements, systems and structures; identification of the causes and extent of damage, faults and deficits, assessing the vulnerability and level of exposure of the asset to the aggression of environmental factors and related risks; evaluation of the compatibility between the characteristics of the available spaces, the primary needs of conservation, the instance of regeneration and possible new uses; the definition of criteria and guidelines for establishing the planning of conservation, restoration and redevelopment interventions.

The present paper analyzes the implementation of Open Digital Television (Televisión Digital Abierta or TDA) in Argentina. It takes up a sociotechnical standpoint and considers TDA as a public policy designed to foster social inclusion.

The ideas presented in this paper are derived from a sociotechnical perspective, both at a theoretical and at a methodological level. The main postulates of this perspective are based on constructivist criteria; they explain outcomes as a result of the constant interplay of technical and social realities. Thus, this relation is intrinsic and continuous. We work with the concept of technology in its broadest sense. That is to say, TDA is not seen as just a mass communication infrastructure, but as a technology which involves knowledge, production practices, and content broadcasting, as a result of the interrelation of cultural, political, social, economic, scientific, and technological factors. The study of TDA in Argentina as a public policy for social inclusion shows how the constant sociotechnical interrelations have to be taken into account (technical standard, antenna features, social actors involved, produced content, etc.) throughout the whole process, from the conception and design of public policies to their implementation, but mainly at the stage of results analysis.

We concluded that throughout the implementation of the TDA public policy, a determinist view of technology prevailed. This can be seen in relation to both the role of television as a medium for social inclusion and the actions regarding the role of the user. The idea of viewer in the traditional sense prevailed over the idea of an active user. This stage provides significant data to assess the range and the limitations of the current public policy, and to think of improvements to implement in the future. These observations suggest a new challenge lying on the horizon: to construct a new concept of television; that is, to analyze TV as a social actor that is crucial for social inclusion rather than simply a medium of mass communication.

The sociotechnical perspective sheds light on the actors involved in the development, implementation, and production of a public policy designed for social inclusion. It focuses both on the government plan and the usage practices of the users themselves. The approach we propose for the study of the relation between technology and public policy is consistent with the notion of an active government.

The value of this paper lies in its theoretical and methodological approach, since a sociotechnical analysis grounded on relativism is a different view to the one that is dominant in studies in the field of communication and public policies. This view offers innovative insights into the problems regarding TDA by exploring the interrelations between actors and the power relations embedded in the public policy.