Mantle flow, volatiles, slab-surface temperatures and melting dynamics in the north Tonga arc-Lau back-arc basin

The Fonualei Spreading Center affords an excellent opportunity to evaluate geochemical changes with increasing depth to the slab in the Lau back-arc basin. We present H2O and CO2 concentrations and Sr, Nd, Pb, Hf and U-Th-Ra isotope data for selected glasses as well as new Hf isotope data from boninites and seamounts to the north of the Tonga arc. The Pb and Hf isotope data are used to show that mantle flow is oriented to the southwest and that the tear in the northern end of the slab may not extend east as far as the boninite locality. Along the Fonualei Spreading Center, key geochemical parameters change smoothly with increasing distance from the arc front and increasing slab surface temperatures. The latter may range from 720 to 866 degrees C, based on decreasing H2O/Ce ratios. Consistent with experimental data, the geochemical trends are interpreted to reflect changes in the amount and composition of wet pelite melts or super-critical fluids and aqueous fluids derived from the slab. With one exception, all of the lavas preserve both U-238 excesses and Ra-226 excesses. We suggest that lavas from the Fonualei Spreading Center and Valu Fa Ridge are dominated by fluid-fluxed melting whereas those from the East and Central Lau Spreading Centers, where slab surface temperatures exceed similar to 850-900 degrees C, are largely derived through decompression. A similar observation is found for the Manus and East Scotia back-arc basins and may reflect the expiry of a key phase such as lawsonite in the subducted basaltic crust.

A Microscopic Study of Iron and Manganese Oxide Distribution in Soils from East Tennessee (U.S.A.)

Soils and saprolites developed from interbedded shales and limestones of the Conasauga Group are widespread in the Valley and Ridge Province of East Tennessee. Thin sections from four soil profiles were examined by petrographic and scanning electron microscopy including backscatter electron and energy-dispersive X-ray analyses. Iron and manganese released by weathering had migrated differentially downward and precipitated as crystalline and noncrystalline oxides. Oxides were observed as nodules, granular particulates, pore fillings, and coatings on other minerals, packing voids, vesicles, channels, and chambers. Iron oxides formed predominantly as coatings on packing-void walls and on laminated clays in vesicles and channels. Manganese oxides occurred as an early replacement phase of packing voids and of fracture-filling carbonate minerals. Iron oxides were dominant in moderately well-drained and oxidized horizons of the soil solum, whereas manganese oxides were abundant in the oxidized and moderately leached saprolite zone where the water table fluctuates seasonally. Therefore, a manganese enrichment zone, on a bulk soil basis, occurred generally below the iron oxide zone in the soil profile. Such differential migration and accumulation of iron and manganese have been controlled by localized soil microenvironments. Micromorphologic features observed in this study are important in land-use evaluation for hazardous waste disposal. © 1990.

238.2T-14 Concrete Thixotropy

Fresh concrete can exhibit different rheological behavior when at rest than when flowing. This difference is due to thixotropy, which can have important consequences for formwork pressure, multi-lift casting, slip-form paving, pumping, and segregation resistance. This TechNote defines thixotropy and distinguishes it from other changes in rheological properties; discusses the origins of, test methods for measuring, and factors affecting thixotropy; and concludes with its applications.

The 'human revolution' in lowland tropical Southeast Asia:the antiquity and behavior of anatomically modern humans at Niah Cave (Sarawak, Borneo)

Recent research in Europe, Africa, and Southeast Asia suggests that we can no longer assume a direct and exclusive link between anatomically modern humans and behavioral modernity (the 'human revolution'), and assume that the presence of either one implies the presence of the other: discussions of the emergence of cultural complexity have to proceed with greater scrutiny of the evidence on a site-by-site basis to establish secure associations between the archaeology present there and the hominins who created it. This paper presents one such case study: Niah Cave in Sarawak on the island of Borneo, famous for the discovery in 1958 in the West Mouth of the Great Cave of a modern human skull, the 'Deep Skull,' controversially associated with radiocarbon dates of ca. 40,000 years before the present. A new chronostratigraphy has been developed through a re-investigation of the lithostratigraphy left by the earlier excavations, AMS-dating using three different comparative pre-treatments including ABOX of charcoal, and U-series using the Diffusion-Absorption model applied to fragments of bones from the Deep Skull itself. Stratigraphic reasons for earlier uncertainties about the antiquity of the skull are examined, and it is shown not to be an `intrusive' artifact. It was probably excavated from fluvial-pond-desiccation deposits that accumulated episodically in a shallow basin immediately behind the cave entrance lip, in a climate that ranged from times of comparative aridity with complete desiccation, to episodes of greater surface wetness, changes attributed to regional climatic fluctuations. Vegetation outside the cave varied significantly over time, including wet lowland forest, montane forest, savannah, and grassland. The new dates and the lithostratigraphy relate the Deep Skull to evidence of episodes of human activity that range in date from ca. 46,000 to ca. 34,000 years ago. Initial investigations of sediment scorching, pollen, palynomorphs, phytoliths, plant macrofossils, and starch grains recovered from existing exposures, and of vertebrates from the current and the earlier excavations, suggest that human foraging during these times was marked by habitat-tailored hunting technologies, the collection and processing of toxic plants for consumption, and, perhaps, the use of fire at some forest-edges. The Niah evidence demonstrates the sophisticated nature of the subsistence behavior developed by modern humans to exploit the tropical environments that they encountered in Southeast Asia, including rainforest. (c) 2006 Elsevier Ltd. All rights reserved.

Fungal stress biology: A preface to the Fungal Stress Responses special edition

There is currently an urgent need to increase global food security, reverse the trends of increasing cancer rates, protect environmental health, and mitigate climate change. Toward these ends, it is imperative to improve soil health and crop productivity, reduce food spoilage, reduce pesticide usage by increasing the use of biological control, optimize bioremediation of polluted sites, and generate energy from sustainable sources such as biofuels. This review focuses on fungi that can help provide solutions to such problems. We discuss key aspects of fungal stress biology in the context of the papers published in this Special Issue of Current Genetics. This area of biology has relevance to pure and applied research on fungal (and indeed other) systems, including biological control of insect pests, roles of saprotrophic fungi in agriculture and forestry, mycotoxin contamination of the food-supply chain, optimization of microbial fermentations including those used for bioethanol production, plant pathology, the limits of life on Earth, and astrobiology.

Mitigation of concrete cover separation in frpstrengthened RC beams using FRP U-jackets

Concrete cover separation is a common failure mode of reinforced concrete (RC) beams strengthened with a fibre-reinforced polymer (FRP) plate bonded to the tension face (FRP-plated RC beams). Plate-end FRP U-jackets have previously been explored as a mitigation measure to delay or suppress concrete cover separation, although its effectiveness needs further clarification. The paper presents the first systemic experimental study on the use of FRP U-jackets of different forms for mitigating the concrete cover separation failure. A total of ten full-scale FRP-plated RC beams were tested. The test results show that both the ultimate load and the ductility of the beams were enhanced by the U-jackets. Among the forms of U-jackets explored, those inclined at 45o are the most effective.

Beyond the Academy: Applying Anthropological Research, A Case Study of Demonstrating Impact in the U.K. 2014 REF

The 2014 Research Excellence Framework sought for the first time to assess the impact that research was having beyond the boundaries of the university and the wider academic sphere. While the REF continued the approach of previous research assessment exercises in attempting to measure the overall quality of research and teaching within the higher-education sector, it also expected institutions to evidence how some of their research had had ‘an effect on, change or benefit to the economy, society, culture, public policy or services, health, the environment or quality of life, beyond academia’ (REF 2012: 48). This article provides a case study in how researchers in one U.K. anthropology department were able to demonstrate the impact of their work in the public sphere successfully as part of this major audit exercise.

Diseño de resortes helicoidales circulares a compresión aplicado a una matriz de corte existente en la escuela de Ingeniería Mecánica de la U.P.S.

El presente trabajo consiste en el estudio sobre el diseño de resortes helicoidales circulares a presión. El capítulo I contiene la Hipótesis, Objetivos (generales y específicos), cuestionamientos y alcances del tema de la presente tesis. El capítulo II presenta una información acerca de lsos istemas con miembros elásticos y la variación de la energía potencial elástica. El siguiente capítulo da a conocer las clases de resortes, su representación y acotación según las normas de dibujo técnico. El último capítulo trata sobre el desarrollo de la parte experimental de la tesis con el cálculo de un resorte helicoidal circular aplicado a una matriz de corte; procedimiento para el cálculo de estos elementos; y , el análisis de los valores obtenidos teóricamente con los reales.

U-TRACER® - the use of communication technology in higher education - an information visualization tool for the context of Portuguese public higher education

Information Visualization is gradually emerging to assist the representation and comprehension of large datasets about Higher Education Institutions, making the data more easily understood. The importance of gaining insights and knowledge regarding higher education institutions is little disputed. Within this knowledge, the emerging and urging area in need of a systematic understanding is the use of communication technologies, area that is having a transformative impact on educational practices worldwide. This study focused on the need to visually represent a dataset about how Portuguese Public Higher Education Institutions are using Communication Technologies as a support to teaching and learning processes. Project TRACER identified this need, regarding the Portuguese public higher education context, and carried out a national data collection. This study was developed within project TRACER, and worked with the dataset collected in order to conceptualize an information visualization tool U-TRACER®. The main goals of this study related to: conceptualization of the information visualization tool U-TRACER®, to represent the data collected by project TRACER; understand higher education decision makers perception of usefulness regarding the tool. The goals allowed us to contextualize the phenomenon of information visualization tools regarding higher education data, realizing the existing trends. The research undertaken was of qualitative nature, and followed the method of case study with four moments of data collection.The first moment regarded the conceptualization of the U-TRACER®, with two focus group sessions with Higher Education professionals, with the aim of defining the interaction features the U-TRACER® should offer. The second data collection moment involved the proposal of the graphical displays that would represent the dataset, which reading effectiveness was tested by end-users. The third moment involved the development of a usability test to the UTRACER ® performed by higher education professionals and which resulted in the proposal of improvements to the final prototype of the tool. The fourth moment of data collection involved conducting exploratory, semi-structured interviews, to the institutional decision makers regarding their perceived usefulness of the U-TRACER®. We consider that the results of this study contribute towards two moments of reflection. The challenges of involving end-users in the conceptualization of an information visualization tool; the relevance of effective visual displays for an effective communication of the data and information. The second relates to the reflection about how the higher education decision makers, stakeholders of the U-TRACER® tool, perceive usefulness of the tool, both for communicating their institutions data and for benchmarking exercises, as well as a support for decision processes. Also to reflect on the main concerns about opening up data about higher education institutions in a global market.

From the Government to the Streets: Why the U.S. is a Policy Innovator in Disability Rights

Thesis (Ph.D.)--University of Washington, 2012

A Meteorological and Snow observational data set from Snoqualmie Pass (921 m), Washington Cascades, U.S.

We introduce a quality controlled observational atmospheric, snow, and soil data set from Snoqualmie Pass, Washington, U.S.A., to enable testing of hydrometeorological and snow process representations within a rain-snow transitional climate where existing observations are sparse and limited. Continuous meteorological forcing (including air temperature, total precipitation, wind speed, specific humidity, air pressure, short- and longwave irradiance) are provided at hourly intervals for a 24-year historical period (water years 1989-2012) and at half-hourly intervals for a more-recent period (water years 2013-2015), separated based on the availability of observations. Additional observations include 40-years of snow board new snow accumulation, multiple measurements of total snow depth, and manual snow pits, while more recent years include sub-daily surface temperature, snowpack drainage, soil moisture and temperature profiles, and eddy co-variance derived turbulent heat flux. This data set is ideal for testing hypotheses about energy balance, soil and snow processes in the rain-snow transition zone. Plots of live data can be found here: http://depts.washington.edu/mtnhydr/cgi/plot.cgi