20,930 research outputs found
Culture Techniques for Rearing Soil Anthropods
Excerpt: Interest in soil biology has been prompted by recent investigations into the action of insecticides on plants and animals. Observations in the field must be supplemented by laboratory investigations conducted under controlled conditions. Consequently, it becomes necessary to rear and handle soil animals under artificial situations for bio-assay and life cycle studies. When large numbers of individuals are required, special problems in maintenance and manipulation arise. Relatively inexpensive and simple methods for such projects are essential and this paper describes some of those techniques which we have found expedient
Summary of the Structure Function Session at Dis01
The status and ongoing developments in the field of deep inelastic scattering
presented at the DIS01 workshop in Bologna are discussed from both the
experimental and the theoretical perspective.Comment: Invited talk presented at the 9th International Workshop on Deep
Inelastic Scattering (DIS 2001), Bologna, Italy, 27 Apr - 1 May 2001, to
appear in the Proceedings. (30 pages, 17 figures
Housing outcomes: an assessment of long-term trends
This paper was presented at the conference "Unequal incomes, unequal outcomes? Economic inequality and measures of well-being" as part of session 2, " Affordability of housing for young and poor families." The conference was held at the Federal Reserve Bank of New York on May 7, 1999. The authors examine trends in housing outcomes by income group. Orr and Peach indicate that there has been a substantial improvement in the physical adequacy of the housing stock over the past few decades, particularly for households in the lowest income quintile. Neighborhood quality for all income groups has also improved, although sharp differences in quality continue to exist across the groups. In one important respect, however, lower income households are worse off than before - housing costs now absorb a larger share of their income.Housing ; Housing - Finance
The topology of deformation spaces of Kleinian groups
Let M be a compact, hyperbolizable 3-manifold with nonempty incompressible
boundary and let AH(\pi_1(M)) denote the space of (conjugacy classes of)
discrete faithful representations of \pi_1(M) into PSL 2 (C). The components of
the interior MP(\pi_1(M)) of AH(\pi_1(M)) (as a subset of the appropriate
representation variety) are enumerated by the space A(M) of marked
homeomorphism types of oriented, compact, irreducible 3-manifolds homotopy
equivalent to M. In this paper, we give a topological enumeration of the
components of the closure of MP(\pi_1(M)) and hence a conjectural topological
enumeration of the components of AH(\pi_1(M)). We do so by characterizing
exactly which changes of marked homeomorphism type can occur in the algebraic
limit of a sequence of isomorphic freely indecomposable Kleinian groups. We use
this enumeration to exhibit manifolds M for which AH(\pi_1(M)) has infinitely
many components.Comment: 49 pages, published versio
REGIONAL COST SHARE NECESSARY FOR RANCHER PARTICIPATION IN BRUSH CONTROL
Large-scale brush-control programs are being proposed in Texas to increase off-site water yields. Biophysical and economic simulation models are combined to estimate the effects of brush control on representative ranches in four ecological regions of the Edwards Plateau area of Texas. Net present values of representative ranches in three of four regions decrease with brush control. Cost shares necessary for ranches from the three regions to break even range from 7% to 31% of total brush-control costs. Any large-scale brush-control program will therefore require a substantial investment by the state of Texas.Agribusiness,
Trees and Matchings
In this article, Temperley's bijection between spanning trees of the square
grid on the one hand, and perfect matchings (also known as dimer coverings) of
the square grid on the other, is extended to the setting of general planar
directed (and undirected) graphs, where edges carry nonnegative weights that
induce a weighting on the set of spanning trees. We show that the weighted,
directed spanning trees (often called arborescences) of any planar graph G can
be put into a one-to-one weight-preserving correspondence with the perfect
matchings of a related planar graph H.
One special case of this result is a bijection between perfect matchings of
the hexagonal honeycomb lattice and directed spanning trees of a triangular
lattice. Another special case gives a correspondence between perfect matchings
of the ``square-octagon'' lattice and directed weighted spanning trees on a
directed weighted version of the cartesian lattice.
In conjunction with results of Kenyon, our main theorem allows us to compute
the measures of all cylinder events for random spanning trees on any (directed,
weighted) planar graph. Conversely, in cases where the perfect matching model
arises from a tree model, Wilson's algorithm allows us to quickly generate
random samples of perfect matchings.Comment: 32 pages, 19 figures (minor revisions from version 1
A long and winding road: defining the biological role and clinical importance of paraoxonases
Paraoxonase-1 (PON1) is an enzyme belonging to a three-member gene family, each of which is highly conserved in mammalian evolution. Whilst there is consensus that the paraoxonase family members have a general protective influence, their precise biological role has remained elusive. A toxicological role, protecting from environmental poisoning by organophosphate derivatives, drove much of the earlier work on the enzymes. More recently, clinical interest has focused on a protective role in vascular disease via a hypothesised impact on lipoprotein lipid oxidation. Recent confirmation that the primary activity of the paraoxonases is that of a lactonase considerably expands the potential sources of biological substrates for the enzyme. Studies on such substrates may shed further light on different mechanisms by which paraoxonases beneficially influence atherosclerosis, as well as defining possible roles in limiting bacterial infection and in innate immunity. Clin Chem Lab Med 2006;44:1052-
Trademark Law - Lanham Trademark Act of 1946 - Trademark Registration
The United States Supreme Court held that when a color meets the ordinary requirements of a trademark, there is no special rule preventing color alone from serving as a trademark.
Qualitex Co. v. Jacobson Products Co., 115 S. Ct. 1300 (1995)
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