27,202 research outputs found
Solid-state Isotopic Power Source for Computer Memory Chips
Recent developments in materials technology now make it possible to fabricate nonthermal thin-film radioisotopic energy converters (REC) with a specific power of 24 W/kg and a 10 year working life at 5 to 10 watts. This creates applications never before possible, such as placing the power supply directly on integrated circuit chips. The efficiency of the REC is about 25 percent which is two to three times greater than the 6 to 8 percent capabilities of current thermoelectric systems. Radio isotopic energy converters have the potential to meet many future space power requirements for a wide variety of applications with less mass, better efficiency, and less total area than other power conversion options. These benefits result in significant dollar savings over the projected mission lifetime
Bridges
This entry discusses the linguistic (prosodic) features of the Ancient Greek poetic phenomenon of the metrical bridge, a position in a line of verse where a word division is either disallowed or strongly disfavored
Quantum homogeneous spaces of connected Hopf algebras
Let H be a connected Hopf k-algebra of finite Gel'fand-Kirillov dimension
over an algebraically closed field k of characteristic 0. The objects of study
in this paper are the left or right coideal subalgebras T of H. They are shown
to be deformations of commutative polynomial k-algebras. A number of well-known
homological and other properties follow immediately from this fact. Further
properties are described, examples are considered, invariants are constructed
and a number of open questions are listed.Comment: 26 pages; comments welcom
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The Irrelevance of Trade Union Recognition? A Comparison of Two Matched Companies
Two UK business services companies are compared both to each other and to their common state-owned industry background in order to assess the implications of trade union recognition and changed bargaining structure. Union recognition had been abandoned by one company under the agenda of "individualization" and "personal contracts" but retained by the other under the agenda of "partnership". Changes in the level at which employment relationships are regulated occurred at both companies relative to their ancestral public enterprises. The similarity of the companies in terms of products, technologies and institutional history provides an approximation to a natural experiment. The evidence suggests only secondary effects from union presence upon operational attributes and economic performance, but major effects from the decentralization of employment relations, which formed part of a wider and more radical set of changes in the relevant markets, technologies, ownership structures and labour law
St. Regis Mohawk Trip Report: Assessment of Mold and Moisture Conditions
Kate Brown of the Building Research Council at the University of Illinois and Paul Knight of Magna Systems, Inc. conducted a site visit at the St. Regis Mohawk Reservation on December 9-11, 2002. The purpose of the site visit was to conduct onsite assessments of mold and moisture conditions in homes located on the reservation. This is a summary report of activities and issues identified while on site. A detailed analysis of the findings and recommendations is found in the attached report, titled: Technical Housing Assessment Report: Examining Mold and Moisture Conditions of Homes on the St. Regis Mohawk Reservation.U.S. Department of Housing and Urban Development, Office of Native American Program
Hopf algebras under finiteness conditions
This is a brief survey of some recent developments in the study of infinite
dimensional Hopf algebras which are either noetherian or have finite
Gelfand-Kirillov dimension. A number of open questions are listed.Comment: Comments welcom
Reversibility of cell surface label rearrangement
Cell surface labeling can cause rearrangements of randomly distributed membrane components. Removal of the label bound to the cell surface allows the membrane components to return to their original random distribution, demonstrating that label is necessary to maintain as well as to induce rearrangements. With scanning electron microscopy, the rearrangement of concanavalin A (con A) and ricin binding sites on LA-9 cells has been followed by means of hemocyanin, a visual label. The removal of con A from its binding sites at the cell surface with alpha- methyl mannoside, and the return of these sites to their original distribution are also followed in this manner.
There are labeling differences with con A and ricin. Under some conditions, however, the same rearrangements are seen with both lectins. The disappearance of labeled sites from areas of ruffling activity is a major feature of the rearrangements seen. Both this ruffling activity and the rearrangement of label are sensitive to cytochalasin B, and ruffling activity, perhaps along with other cytochalasin-sensitive structure, may play a role in the rearrangements of labeled sites
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