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Developing a design methodology for the construction of hypertext and hypermedia, with particular reference to hypertext electronic prospectuses
Use and development of hypertext-based documents is becoming more widespread in both industry and die academic world. This has obvious implications for the design of hypertext documents. The hypertext designer has been relatively ignored until recently, with attention largely focused on the quality of the hypertext rather than support for the designer. Recent hypertext design methodologies, such as that described by Isakowitz et al. (1995) have made a useful contribution, but are oriented towards designers with a background in computing science and related professions.
This research addresses this problem by the development of a design methodology which is intended to be accessible to the general author. The design methodology was based on three sources of data: a taxonomy of existing design guidance, including a range of principles and guidelines and previous design methodologies for hypertext; hypertext versions of a higher education college prospectus, and a case study of a CD-ROM higher education prospectus.
This material was assembled and synthesised to produce a provisional design methodology that is positioned between existing design methodologies such as Relationship Management Methodology (Isakowitz et al 1995) and Object-Oriented Hypermedia Design Method (Schwabe et al 1995), which are influenced by software engineering and database design concepts, and other less formal descriptions of the hypertext design process. The design methodology supports and encourages iterative methods of working, and includes supporting documentation and pro formas designed to encourage a thorough approach to hypertext design
Operational criteria used by professional social workers to assess relationship
Thesis (M.S.)--Boston Universit
Characterization of the human omega-oxidation pathway for omega-hydroxy-very-long-chain fatty acids
Very-long-chain fatty acids (VLCFAs) have long been known to be degraded exclusively in peroxisomes via beta-oxidation. A defect in peroxisomal beta-oxidation results in elevated levels of VLCFAs and is associated with the most frequent inherited disorder of the central nervous system white matter, X-linked adrenoleukodystrophy. Recently, we demonstrated that VLCFAs can also undergo omega-oxidation, which may provide an alternative route for the breakdown of VLCFAs. The omega-oxidation of VLCFA is initiated by CYP4F2 and CYP4F3B, which produce omega-hydroxy-VLCFAs. In this article, we characterized the enzymes involved in the formation of very-long-chain dicarboxylic acids from omega-hydroxy-VLCFAs. We demonstrate that very-long-chain dicarboxylic acids are produced via two independent pathways. The first is mediated by an as yet unidentified, microsomal NAD(+)-dependent alcohol dehydrogenase and fatty aldehyde dehydrogenase, which is encoded by the ALDH3A2 gene and is deficient in patients with Sjogren-Larsson syndrome. The second pathway involves the NADPH-dependent hydroxylation of omega-hydroxy-VLCFAs by CYP4F2, CYP4F3B, or CYP4F3A. Enzyme kinetic studies show that oxidation of omega-hydroxy-VLCFAs occurs predominantly via the NAD(+)-dependent route. Overall, our data demonstrate that in humans all enzymes are present for the complete conversion of VLCFAs to their corresponding very-long-chain dicarboxylic acids
THE ECONOMIC THRESHOLD FOR GRASSHOPPER CONTROL ON PUBLIC RANGELANDS
The U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) is responsible for controlling grasshopper populations on public rangelands. Under current guidelines, control of grasshoppers on rangeland should occur if grasshopper densities are at least eight per square yard. This article evaluates the concept of an economic threshold relative to the value of forage saved from destruction during a grasshopper outbreak. It is shown that financial justification for treating grasshopper outbreaks depends upon grasshopper density, rangeland productivity, climate factors, livestock cost and return relationships, and the efficacy of treatment options.Resource /Energy Economics and Policy, Land Economics/Use,
Toward canonical trophic aggregations
The attractiveness of the trophic concept is that it was the first attempt at a holistic perspective on an ecosystem which met with any degree of success. Just as temperature, pressure, and volume allow one to characterize the incomprehensible multitude of particulate motions in a simple gas, the hope is that a small set of figures, such as trophic storages or trophic efficiencies, permit one to compare two ecosystems with overwhelmingly disparate complexities. Thus, if it were possible to demonstrate that an arbitrary network of ecosystem flows could be reduced to a trophic configuration, the aggregation process thus defined would become a key component of the evolving discipline of "macroscopic ecology" (see also Odum
1977 and Ulanowicz 1979)
Purpose, Meaning, and Exploring Vocation in Honors Education
This paper examines the importance of cultivating a sense of vocation in honors education. Through examples of coursework, program initiatives, and advising strategies, authors from across five institutions align the scholarship of vocation with best practices and principles in contemporary honors discourse, defining vocation in the context of higher education and describing how this concept works within honors curricula to enrich student experience and cultivate individual understandings of purpose. By focusing on critical reflection processes, Ignatian pedagogy, and theories of moral development and reasoning, the authors offer different models to advance the thesis that honors educators can and should address personal fulfillment in addition to intellectual talent, and they posit vocational exploration and discernment as tools for extending and deepening their students’ personal sense of meaning in local and global communities
Orbital Period Increase in ES Ceti
We report a long-term study of the eclipse times in the 10-minute helium
binary ES Ceti. The binary period increases rapidly, with P/P-dot = 6.2x10^6
yr. This is consistent with the assumption that gravitational radiation (GR)
drives the mass transfer, and appears to be the first dynamical evidence that
GR is indeed the driver of evolution in this class of very old cataclysmic
variables -- the AM Canum Venaticorum stars.Comment: PDF, 9 pages, 1 table, 1 figure; accepted, in press, ApJ; more info
at http://cbastro.org
Tetraethylene Gycol-Based Electrolytes for High Temperature Electrodeposition of Compound Semiconductors
We report an investigation of tetraethylene glycol (TEG) solutions of chloride salts (CdCl2 ,TeCl4 ,and HgCl2 ) for electrodeposition of films of CdTe and Hg1.xCdxTe, leading II-VI semiconductors. The high boiling point (314°C), below-room temperature (T) (-6°C) melting point, adequate metal chloride solubilities, and low toxicity of TEG make it a good candidate for electrodeposition at T \u3e 200°C. Such temperatures tend to activate growth of larger crystallites than with aqueous electrolytes at T\u3c 100 °C, as are advantageous in optoelectronic applications. Initial results do, indeed, indicate a dramatic increase in crystallinity with deposition temperature, especially for the CdTe films which are nearly amorphous when grown at room temperature. Hg1.xCdxTe films (x\u3c 0.5) are marginally polycrystalline when grown at room temperature but also improve in crystallinity at higher growth temperatures. There appears to be a strong decrease in film adherence and uniformity as growth temperature increases for both materials probably because the greatly increased carrier concentrations at higher temperatures increase film conductivity which, in turn, supports easy electroplating of protruding loose dendritic and/or columnar crystallites, instead of the monolayer-by monolayer growth of lower conductivity material as occurs at lower temperatures, especially in the higher bandgap/lower conductivity CdTe. The same increase in film conductivity with temperature is responsible for the decrease in the relative photosensitivity of both the CdTe and Hg1.x CdxTe with temperature. At all temperatures, the inferior adherence, uniformity, and photosensitivity as well as the superior crystallinity of Hg1.xCd xTe over that of the CdTe are also explained by its lower bandgap and higher conductivity. On balance, however, the initial results prove the utility of high temperature TEG electrolytes for electrodepositing CdTe and Hg1.xCdxTe films with much better crystallinity than for those grown at lower temperatures, notably in aqueous baths
Child relationships in the middle grades
Thesis (Ed.M.)--Boston Universit
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