4,146 research outputs found
Investigation of foamed metals for application on space capsules annual report, 29 jun. 1963 - 15 aug. 1964
Foamed metal development for space capsules - brazing, variable density beam, thermal testing, mechanical tests, and machinin
Notorious places: image, reputation, stigma: the role of newspapers in area reputations for social housing estates
This paper reviews work in several disciplines to distinguish between image, reputation and stigma. It also shows that there has been little research on the process by which area reputations are established and sustained through transmission processes. This paper reports on research into the portrayal of two social housing estates in the printed media over an extended period of time (14 years). It was found that negative and mixed coverage of the estates dominated, with the amount of positive coverage being very small. By examining the way in which dominant themes were used by newspapers in respect of each estate, questions are raised about the mode of operation of the press and the communities' collective right to challenge this. By identifying the way regeneration stories are covered and the nature of the content of positive stories, lessons are drawn for programmes of area transformation. The need for social regeneration activities is identified as an important ingredient for changing deprived-area reputations
Estimating long-term volatility parameters for market-consistent models
Contemporary actuarial and accounting practices (APN 110 in the South African context) require the use of market-consistent models for the valuation of embedded investment derivatives. These models have to be calibrated with accurate and up-to-date market data. Arguably, the most important variable in the valuation of embedded equity derivatives is implied volatility. However, accurate long-term volatility estimation is difficult because of a general lack of tradable, liquid medium- and long-term derivative instruments, be they exchange-traded or over the counter. In South Africa, given the relatively short-term nature of the local derivatives market, this is of particular concern. This paper attempts to address this concern by: — providing a comprehensive, critical evaluation of the long-term volatility models most commonly used in practice, encompassing simple historical volatility estimation and econometric, deterministic and stochastic volatility models; and — introducing several fairly recent nonparametric alternative methods for estimating long-term volatility, namely break-even volatility and canonical option valuation. The authors apply these various models and methodologies to South African market data, thus providing practical, long-term volatility estimates under each modelling framework whilst accounting for real-world difficulties and constraints. In so doing, they identify those models and methodologies they consider to be most suited to long-term volatility estimation and propose best estimation practices within each identified area. Thus, while application is restricted to the South African market, the general discussion, as well as the suggestion of best practice, in each of the evaluated modelling areas remains relevant for all long-term volatility estimation
Relative Roles of TGF-β and IGFBP-5 in Idiopathic Pulmonary Fibrosis
Although most evident in the skin, the process of scarring, or fibrosis, occurs in all major organs because of impaired epithelial self-renewal. No current therapy exists for Idiopathic pulmonary fibrosis. The major profibrotic factor is TGF-β1 and developing inhibitors is an area of active research. Recently, IGFBP-5 has also been identified as a profibrotic factor, and studies suggest that, while both TGF-β1 and IGFBP-5 activate mesenchymal cells to increase collagen and fibronectin production, their effects on epithelial cells are distinct. TGF-β1 induces cell death and/or EMT in the epithelial cells, exacerbating the disruption of tissue architecture. In contrast, IGFBP-5 induces epithelial cell spreading over collagen or fibronectin matrices, increases secretion of laminin, the epithelial basement membrane, and enhances the survival of epithelial cells in nutrient-poor conditions, as exists in scar tissue. Thus, IGFBP-5 may enhance repair and may be an important target for antifibrotic therapies
Governor versus Colonial Office: An Anatomy of the Richards Constitution for Nigeria, 1939 to 1945
La constitution Richards a posé la base de tout le processus de décolonisation du Nigeria, voire même, de toute l'Afrique britannique. Pour la première fois, le pays entier était soumis à une même constitution et des assemblées régionales étaient établies. Le pays s'acheminait vers un statut fédéral et tout indiquait clairement que la décolonisation était amorcée. Toutefois, la façon dont elle fut imposée fit en sorte que les politiciens nationalistes refusèrent de s'y rallier.L'auteur examine ici les modes d'implantation différents que préconisèrent, à l'époque, le « Colonial Office » à Londres, d'une part, et le gouverneur Sir Arthur Richards, d'autre part. Il soutient, de fait, que la philosophie réactionnaire de Richards fut en opposition constante avec les idées mises de l'avant par le « Colonial Office ». Il démontre, de plus, que la résistance offerte par Richards a effectivement détruit les chances qu'avait la Grande Bretagne d'organiser et de diriger le mouvement nationaliste, voire même, que ce faisant, il a suscité l'apparition des partis nationalistes au Nigeria
Exploring User Interface Improvements for Software Developers who are Blind
Software developers who are blind and interact with the computer non-visually face unique challenges with information retrieval. We explore the use of speech and Braille combined with software to provide an improved interface to aid with challenges associated with information retrieval. We motivate our design on common tasks performed by students in a software development course using a Microprocessor without Interlocked Pipeline Stages (MIPS) architecture simulation tool. We test our interface via a single-subject longitudinal study, and we measure and show improvement in both the user’s performance and the user experience
Ecological Impacts of the 2015/16 El Niño in the Central Equatorial Pacific
The authors thank Cisco Werner (NOAA/NMFS) for proposing this special issue and encouraging our submission. We thank each of the editors, Stephanie Herring, Peter Stott, and Nikos Christidis, for helpful guidance and support throughout the submittal process. We also thank each of the anonymous external reviewers for thoughtful guidance and suggestions to improve the manuscript. REB, TO, RV, AH, and BVA are grateful for support from the NOAA Coral Reef Conservation Program. AC acknowledges support from the National Science Foundation for the following awards: OCE 1537338, OCE 1605365, and OCE 1031971. This is PMEL contribution no. 4698. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. government. The views expressed in the article are not necessarily those of the U.S. government. (NOAA Coral Reef Conservation Program; OCE 1537338 - National Science Foundation; OCE 1605365 - National Science Foundation; OCE 1031971 - National Science Foundation
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A study protocol for a randomised crossover study evaluating the effect of diets differing in carbohydrate quality on ileal content and appetite regulation in healthy humans
A major component of the digesta reaching the colon from the distal ileum is carbohydrate. This carbohydrate is subject to microbial fermentation and can radically change bacterial populations in the colon and the metabolites they produce, particularly short-chain fatty acids (SCFA). However, very little is currently known about the forms and levels of carbohydrate in the ileum and the composition of the ileal microbiota in humans. Most of our current understanding of carbohydrate that is not absorbed by the small intestine comes from ileostomy models, which may not reflect the physiology of an intact gastrointestinal tract. We will investigate how ileal content changes depending on diet using a randomised crossover study in healthy humans. Participants will be inpatients at the research facility for three separate 4-day visits. During each visit, participants will consume one of three diets, which differ in carbohydrate quality: 1) low-fibre refined diet; 2) high-fibre diet with intact cellular structures; 3) high-fibre diet where the cellular structures have been disrupted (e.g. milling, blending). On day 1, a nasoenteric tube will be placed into the distal ileum and its position confirmed under fluoroscopy. Ileal samples will be collected via the nasoenteric tube and metabolically profiled, which will determine the amount and type of carbohydrate present, and the composition of the ileal microbiota will be measured. Blood samples will be collected to assess circulating hormones and metabolites. Stool samples will be collected to assess faecal microbiota composition. Subjective appetite measures will be collected using visual analogue scales. Breath hydrogen will be measured in real-time as a marker of intestinal fermentation. Finally, an continuous fermentation model will be inoculated with ileal fluid in order to understand the shift in microbial composition and SCFA produced in the colon following the different diets. ISRCTN11327221. [Abstract copyright: Copyright: © 2019 Byrne CS et al.
Cellulosomics, a gene-centric approach to investigating the intraspecific diversity and adaptation of Ruminococcus flavefaciens within the rumen
Peer reviewedPublisher PD
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