1,391 research outputs found
A Vision for and Brief History of Youth Philanthropy
AFP offers this report as both an evaluation and marker of the state of the youth philanthropy field and as a record of the Youth in Philanthropy Summit -- its proceedings, outcomes and next steps. Significant progress was achieved; partnerships were forged; a future was envisioned; and each of the participants agreed to ownership of results. The Summit provided direction for what needs to happen for youth philanthropy to become both recognized as a movement and fully integrated into the national and international consciousness.This document has three primary purposes: to offer information on youth philanthropy, its origins and history; to present the development of the Summit; and to document the key themes and outcomes
Innovative bioceramics
Overall, the benefits of advanced ceramic materials in biomedical applications have been universally appreciated, specifically, in terms of their strength, biocompatibility and wear resistance. However, the amount of supporting data is not large and the continuous development of new methods is pertinent for better understanding of the microstructure-properties relationship and, in general, for obtaining new directives for their further improvement. This paper gives an overview of some of the more innovative applications of bioceramics in medicine. © Institute of Materials Engineering Australasia Ltd - Materials Forum Volume 27 - Published 2004
String Theory Versus Black Hole Complementarity
It is argued that string theory on the Euclidean version of the Schwarzschild
black hole -- the cigar geometry -- admits a zero mode that is localized at the
tip of the cigar. The presence of this mode implies that in string theory,
unlike in general relativity, the tip of the cigar is a special region. This is
in tension with the Euclidean version of the black hole complementarity
principle. We provide some qualitative arguments that link between this zero
mode and the origin of the black hole entropy and firewall at the horizon.Comment: 8 page
Targeted model evaluations for climate services: a case study on heat waves in Bangladesh
Though not a sufficient condition, the ability to reproduce key elements of climate variability over the historical record should be a minimum requirement for placing any confidence in a model's climate forecasts or projections of climate change. When projections are used to guide practical adaptation, model evaluations should focus on the weather and climate events of interest to decision-makers, their physical drivers in the climate system and their variability on decision-relevant timescales. This paper argues for a greater emphasis on such targeted model evaluations to enable useful climate services. We illustrate this approach through a case study on heat waves in Bangladesh, but draw wider conclusions that are applicable to climate services development more broadly. The simulation of heat waves in Bangladesh is evaluated in several climate models, focusing on timescales relevant to the long-term viability of a heat action plan: the average, interannual variability and seasonality of temperature and heat-wave frequency. Where the physical drivers of variability are broadly captured, a considered interpretation of the models could provide insights into future heat-wave behaviour. However, substantial biases are found in the statistics and in some physical drivers of heat, raising questions about the suitability of some of the models for determining certain aspects of future risk. Specifically, simple bias corrections cannot be used to make inferences about possible future changes in various weather statistics such as timing of heat waves during the year. Results emphasize the potential pitfalls of performing only perfunctory climatological evaluations and highlight areas for model improvement in the simulation of South Asian climate variability
Fracture Toughness Of Nanoscale Zirconia Coatings On Titanium Substrates
In the biomedical field, the surface modification of titanium aims to inhibit wear, reduce corrosion and ion release, and promote biocompatibility. Sol-gel-derived ceramic nanoscale coatings show promise due to their relative ease of production, ability to form a physically and chemically uniform coating over complex geometric shapes, and their potential to deliver exceptional mechanical properties due to their nanocrystalline structure. In this study zirconia coatings on titanium were investigated for their fracture toughness
Do Public-Good Oriented Courses In Independent Schools Nurture The Development Of 21st Century Skills In High School Students?
Indiana University-Purdue University Indianapolis (IUPUI)Education is among the industries shifting today to answer evolving global needs and opportunities. Influential organizations and thought leaders are calling for reimagining of teaching and learning. To prepare students for college and professions, an increasing number of K-12 independent schools are beginning to focus on deep learning experiences and building key â21st century skillsâ and competencies. These schools are also interested in their public purpose both as institutional citizens of their local communities and to connect their students to local and global communities. These connections provide students with an authentic context for application of learning and for community contribution. There is also now an opportunity to coordinate curricular goals with developmental goals related to studentsâ social-emotional growth and social responsibility. This study used online surveys taken by students and their teachers to explore whether high school courses with public good themes and experiences in independent schools nurture the development of 21st century skills in students. The eight skills studied were: Critical thinking, collaboration, communication, creativity and innovation, self-direction, global connections, local connections, and the use of technology. The skills were measured through frequency ratings of forty-eight classroom practices. Findings show that both students and teachers believe these courses do nurture each skill â some with greater emphasis. Students reported critical thinking, communication, self-direction and making local connections as the skills most learned in their courses, while teachers reported that students most learned these same skills with the addition of collaboration. Teachers use a number of practices in the classroom to develop 21st century skills and most students found the practices relevant to their course
Comparative study of conversion of coral with ammonium dihydrogen phosphate and orthophosphoric acid to produce calcium phosphates
© 2014, Australasian Ceramic Society. All rights reserved. Biogenic materials like corals, which are readily available, could be used to produce bioceramic materials and address significant advantages due to their unique structures and chemical compositions that contain Mg and Sr. Many conversion processes has been in the past proposed. In this work, a comparison study between the conversion of coral with orthophosphoric acid and ammonium dihydrogen phosphate was conducted. The resultant structures and compositions were studied using XRD, ICP-MS, SEM and FTIR. The results show that with phosphoric acid the coral was converted into mainly monetite (92%). The ammonium dihydrogen phosphate converted approximately 76% of the coral to hydroxyapatite through solid state reactions. The two routes proved to be effective in producing bioceramic materials from corals under moderate conditions of temperature with a basic condition favouring the yield of hydroxyapatite
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Climate information for adaptation: from years to decades
In writing this book, we have prioritized shorter timescales of weather and climate variability because these have most direct relevance to the types of operational and planning decisions made in the health sector. However, in this chapter, we focus on longer-term health decisions that require climate knowledge and information at timescales beyond a year to multiple decades (up to 50 years). This time span incorporates both natural decadal variability and the influences of anthropogenic climate change. It is an extremely challenging timeframe at which to work because of the very limited operational predictive skill at multiannual timescales, and limited confidence about how rainfall may change on longer timescales. Despite these challenges, the timescales under consideration, especially the next five to 20 years, are particularly important when considering how to adapt to climate change. Here we discuss what we do and do not know about the climate in the coming years. We then focus on the practical use of climate information in understanding observed climate impacts on health as well as the prediction of multi-annual to multi-decadal risks. The multi-annual timescale is often referred to as âdecadalâ, even though the forecasts are for periods less than a decade
How Sensitive is the CMB to a Single Lens?
We study the imprints of a single lens, that breaks statistical isotropy, on
the CMB and calculate the signal to noise ratio (S/N) for its detection. We
emphasize the role of non-Gaussianities induced by LCDM weak lensing in this
calculation and show that typically the S/N is much smaller than expected. In
particular we find that the hypothesis that a void (texture) is responsible for
the WMAP cold spot can barely (cannot) be tested via weak lensing of the CMB.Comment: Accepted for publication in JCAP, 24 pages, 5 figure
Reasoning with comparative moral judgements: an argument for Moral Bayesianism
The paper discusses the notion of reasoning with comparative moral judgements
(i.e judgements of the form âact a is morally superior to act bâ) from the point of view of several meta-ethical positions. Using a simple formal result, it is argued that only a version of moral cognitivism that is committed to the claim that moral beliefs come in degrees can give a normatively plausible account of such reasoning. Some implications of accepting such a version of moral cognitivism are discussed
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