9,953 research outputs found
Inferential tests and modelling of functional trait convergence along environmental gradients
The motivation for this paper comes from a recent study which indicated that the influence of environmental filtering should increase with decreasing soil fertility, based on the premise that individuals will employ a resource-retentive strategy in a less productive ecosystem. Mean annual temperature (MAT) is one indicator of the productivity of the ecosystem. We aim to build a more accurate model of environmental filter and want to statistically test whether the environmental filter is stronger when the MAT is lower compared to when it is higher. Our findings throw an interesting insight into how the trait variability changes as a function of MAT and how it could be better modelled
Mortality from infectious pneumonia in metal workers: a comparison with deaths from asthma in occupations exposed to respiratory sensitizers
Introduction: national analyses of mortality in England and Wales have repeatedly shown excess
deaths from pneumonia in welders. During 1979-1990 the excess was attributable
largely to deaths from lobar pneumonia and pneumonias other than bronchopneumonia,
limited to working-aged men, and apparent in other metal fume-exposed occupations.
We assessed findings for 1991-2000 and compared the mortality pattern with that from
asthma in occupations exposed to known respiratory sensitizers.Methods: the Office of National Statistics supplied data on deaths by underlying cause among
men aged 16-74 years in England and Wales during 1991-2000, including age and last
held occupation. We abstracted data on pneumonia for occupations with exposure to
metal fume and on asthma for occupations commonly reported to surveillance schemes
as at risk of occupational asthma. We estimated expected numbers of deaths by applying
age-specific proportions of deaths by cause in the population to the total deaths by age in
each occupational group. Observed and expected numbers were compared for each
cause of death.Results: among working-aged men in metal fume-exposed occupations we found excesses of
mortality from pneumococcal and lobar pneumonia (54 deaths vs. 27.3 expected) and
from pneumonias other than bronchopneumonia (71 vs. 52.4), but no excess from these
causes at older ages, or from bronchopneumonia at any age. The attributable mortality
from metal fume (45.3 excess deaths) compared with an estimated 62.6 deaths from
occupational asthma.Conclusion: exposure to metal fume is a material cause of occupational mortality. The hazard
deserves far more attention than it presently receive
The Nonprofit Quarterly Study on Nonprofit and Philanthropic Infrastructure
Examines trends in the nonprofit sector's support network and financing system and their capacity to address the impact of the financial crisis on small and midsize nonprofits, share organizational survival strategies, and connect them to resources
Anisotropic focusing characteristics of micro-domain structures within crystalline Sr<sub>0.61</sub>Ba<sub>0.39</sub>Nb<sub>2</sub>O<sub>6</sub> : the crystal ball
We report the anisotropic focusing characteristics of a spherically configured region of micro-domains that have been induced within a cubic shaped crystal of Ce:doped Sr0.61Ba0.39Nb2O6. The internal spherical structure focuses extraordinary polarised light, but not ordinary polarised. The spherical region, which is easily observed via scattering, is formed as the crystal cools down, after a repoling cycle through the Curie temperature, with an applied field. Analytic modelling of the thermal gradients that exist within the crystal during cooling reveals a small (< 1°) temperature difference between the central and outside regions. The similarity in shape between these temperature profiles and the observed scattering region suggests a possible mechanism for the growth of this spherical micro-domained structure
An Empirical Examination of Consumer Survey Use in Trademark Litigation
This Article is a comprehensive examination of the use of consumer surveys in trademark litigation cases at the federal level. Previous research has shown consumer surveys can be critical to the outcome of trademark litigation, as they measure the idiosyncratic mental associations and reactions of prospective consumers. For this Article, this study examined 843 trademark infringement and dilution cases spanning 2007 to 2017. The findings reveal consumer surveys are not utilized in trademark litigation as often as research suggests they should be. While consumer surveys are not required in trademark litigation, nor necessarily easy or inexpensive to com- mission, this study shows there are situations where it may be most prudent to produce survey evidence.
This study in this Article also provides insight into the potential impact of consumer surveys on the outcome of both trademark infringement and dilution cases in sports. As instances of trademark infringement and dilution are on the rise, sports apparel brands are actively trying to defend themselves against consumer confusion. In most cases, the findings indicate plaintiffs should seriously consider conducting consumer surveys during litigation, as the potential impact of losing a trademark infringement or dilution case could cost the plaintiff its trademark and, ultimately, its brand
Microstructural characterisation of TiAlTiAu and TiAlPdAu ohmic contacts to AlGaN/GaN
Ti/Al/Ti/Au and Ti/Al/Pd/Au contacts to AlGaN/GaN have been investigated to ascertain the effect of annealing temperature on the structural evolution of the contacts. Ti/Al/Ti/Au contacts become ohmic after rapid thermal annealing at 750°C or higher, corresponding to the formation of an interfacial TiN phase, with inclusions penetrating through the AlGaN layer observed after annealing at 950°C. The Pd layer is shown to be more efficient at inhibiting diffusion of Au to the interface than Ti. Ohmic behaviour was not seen with the Ti/Al/Pd/Au scheme. Either the presence of Au at the interface may improve ohmic behaviour, or the Ti:Al ratio is insufficient in this scheme
Tunneling conductance in Superconductor/Ferromagnet junctions: a self consistent approach
We evaluate the tunneling conductance of clean Ferromomagnet/Superconductor
junctions via a fully self-consistent numerical solution of the microscopic
Bogoliubov-DeGennes equations. We present results for a relevant range of
values of the Fermi wavevector mismatch (FWM), the spin polarization, and the
interfacial scattering strength. For nonzero spin polarization, the conductance
curves vary nonmonotonically with FWM. The FWM dependence of the
self-consistent results is stronger than that previously found in
non-self-consistent calculations, since, in the self-consistent case, the
effective scattering potential near the interface depends on the FWM. The
dependence on interfacial scattering is monotonic. These results confirm that
it is impossible to characterize both the the FWM and the interfacial
scattering by a single effective parameter and that analysis of experimental
data via the use of such one-parameter models is unreliable.Comment: 12 pages, including 8 figure
Penrose Diagram for a Transient Black Hole
A Penrose diagram is constructed for a spatially coherent black hole that
smoothly begins an accretion, then excretes symmetrically as measured by a
distant observer, with the initial and final states described by a metric of
Minkowski form. Coordinate curves on the diagram are computationally derived.
Causal relationships between space-time regions are briefly discussed. The life
cycle of the black hole demonstrably leaves asymptotic observers in an
unaltered Minkowski space-time of uniform conformal scale.Comment: 14 pages, 9 figures, spelling correction
- âŠ