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Academia Letters, 2022

Undercut anchorage in dimension stone cladding, 2011

This paper analyses undercut anchorage technology, in particular its behaviour and performance as a fixing system for dimension stone cladding of rainscreen fac¸ades. Based on a number of mechanical tests using various types of Portuguese stone – three igneous, two sedimentary and one metamorphic – a study was carried out to investigate the relationship between the flexural strength and breaking load of specific and very common stone types. Several physical and mechanical characterisation tests and 130 pull-out tests with 6 and 8 mm cone bolt threads were performed to determine the pull-out load failure on six different stone types: three granite, two limestone and one marble. Finite-element stress analyses were carried out, and the test results were the basis for calibrating a simple formula that can be used to estimate the stone’s breaking load at the undercut anchorage. Stress concentration factors are proposed to take into account the undercut drill hole geometry and the specific properties of each type of stone. Stone specimens from the same batches were subject to pull-out force tests using dowel anchorages, whose values were then compared with the breaking load of undercut anchorages. Results are discussed and conclusions are drawn based on tensile stress values by comparing the test results, the finite-element method and the proposed semiempirical formulations for the same breaking load.

Vitamin C (ascorbic acid, ascorbate) has a controversial history in cancer treatment. Emerging evidence indicates that ascorbate in cancer treatment deserves re-examination. As research results concerning ascorbate pharmacokinetics and its mechanisms of action against tumor cells have been published, and as evidence from case studies has continued to mount that ascorbate therapy could be effective if the right protocols were used, interest among physicians and scientists has increased.

Přehled výzkumů 65-1, 2024

The Emireh point is a triangular point, which distinctive bulb of percussion was eliminated with bifacial thinning applied to proximal part of the artefact. This point is a characteristic tool for the Emiran industries and up to yet reported from Levantine sites only. Recently, an isolated Emireh point was excavated at Bohunician site Ořechov IV in South Moravia, ca 3,000 km as the crow flies from Levantine sites.

Colombia Internacional, 2024

Objetivo/contexto: el artículo analiza las tensiones en la construcción de verdades oficiales y alternativas sobre la represión ejercida hacia los pobladores durante la dictadura cívico-militar en Chile (1973-1990). Pese a la envergadura y masividad que adquirió tal represión, solo se ha reconocido oficialmente de modo nominal y excluyente. A partir de una reconstrucción sociohistórica del lugar que ha ocupado la represión contra los sectores empobrecidos de la ciudad, indagamos en las narrativas contenidas en informes oficiales de las comisiones de verdad y las respuestas alternativas de la sociedad civil. Metodología: estudio de caso basado en el análisis documental de informes, prensa y bibliografía secundaria. Conclusiones: se pone en evidencia el carácter contencioso que han ocupado los pobladores en las narrativas canónicas alrededor de la violencia política durante la dictadura cívico-militar. En tal contexto, la sociedad civil ha tenido un rol clave en la disputa por los sentidos y temporalidades de la violencia, y se discute el lugar de los pobladores como actor clave en las dinámicas políticas de las últimas décadas. Originalidad: debido a la escasez de trabajos que enfaticen la representación de los pobladores en la construcción de verdades oficiales y alternativas, nuestros hallazgos ponen en evidencia los vacíos y deudas en la construcción de verdades en torno a los lugares y sujetos de la violencia a cincuenta años del golpe de Estado en Chile.

Philosophers and social theorists of color examine how racism can creep into defensive forms of nationalism. “What does it mean today to be an ‘American’ when one does not represent or embody the norm of ‘Americanness’ because of one’s race, ethnicity, culture of origin, religion, or some combination of these? What is the norm of ‘Americanness’ today, how has it changed, and how pluralistic is it in reality?” — from the Introduction In this volume philosophers and social theorists of color take up these questions, offering nuanced critiques of race and nationalism in the post-9/11 United States focused around the themes of freedom, unity, and homeland. In particular, the contributors examine how normative concepts of American identity and unity come to be defined and defended along increasingly racialized lines in the face of national trauma, and how nonnormative Americans experience the mistrust that their identities and backgrounds engender in this way. The volume takes an important step in recognizing and challenging the unreflective notions of nationalism that emerge in times of crisis. “The idealized and abstract nation-state may be a familiar topic for political investigation, but the actual white nation and its racial state are territory far less explored. This stimulating set of essays—ranging from a reading of post-9/11 children’s literature to an analysis of the racialized aesthetic of white nationalism—provides a valuable and eye-opening introduction to the racial construction of the American polity.” — Charles W. Mills, author of The Racial Contract “A smart and unique set of theoretical reflections on the constitutive role of race and ethnicity in the post-9/11 U.S. American political imaginary, this book should find its place on the bookshelves of everyone interested in questions of citizenship and belonging in a multiracial U.S. polity.” — Chandra Talpade Mohanty, author of Feminism without Borders: Decolonizing Theory, Practicing Solidarity http://www.sunypress.edu/p-4893-constructing-the-nation.aspx

Internet Archaeology, 2002

This article discusses the production of a CD-Rom - Journeys in the Roman Empire - produced by the British Museum, Verulamium Museum and Braunarts. The CD-Rom is no longer in production and cannot be played on modern platforms.

NDT & E International, 2016

Ultrasonic inspection of austenitic welds is challenging due to their highly anisotropic and heterogeneous microstructure. The weld anisotropy causes a steering of the ultrasonic beam leading to a number of adverse effects upon ultrasonic array imagery, including defect mislocation and aberration of the defect response. A semi-analytical model to simulate degraded ultrasonic images due to propagation through an anisotropic austenitic weld is developed. Ray-tracing is performed using the A* path-finding algorithm and integrated into a semi-analytical beam-simulation and imaging routine to observe the impact of weld anisotropy on ultrasonic imaging. Representative anisotropy weld-maps are supplied by the MINA model of the welding process. A number of parametric studies are considered, including the magnitude and behaviour of defect mislocation and amplitude as the position of a fusion-face defect and the anisotropy distribution of a weld is varied, respectively. Furthermore, the use of the model to efficiently simulate and evaluate ultrasonic image degradation due to anisotropic austenitic welds during an inspection development process is discussed.