1,429 research outputs found
Behavioural ecology of the lapwing Vanellus vanellus L. In upper Teesdale
From 1993-95, the behavioural ecology of the Lapwing Vanellus vanellus L. was studied in Upper Teesdale, Co. Durham, with the aim of describing the behavioural mechanisms underlying some population characteristics. Significant effects of age and individuals were found in many aspects of Lapwing breeding biology. Older Lapwings returned to the breeding grounds before yearlings, with adult males returning earliest of all. First breeding attempts occurred at one-year-old for most females, but at two-years-old for most males. Males two-years-old and over showed a remarkable degree of consistency in breeding status (breeding or non-breeding) in consecutive years, even where this meant persistent non-breeding. The age of first breeding, and consistency of breeding status among males, indicates intense intermale competition for limited breeding habitat, with some males, perhaps of low quality, apparently permanently prevented from breeding. However, few differences in annual breeding success were found among females of different ages. With the exception of egg size in first clutches, where yearling females laid eggs around 5% smaller than adults, yearling and adult females were similarly fecund. Laying dates and egg volumes in first clutches exhibited high indices of repeatability between years, probably reflecting a high degree of heritability of these traits. High frequencies of polygyny were recorded, despite the traditional view of strict monogamy for this species. The mating success of male Lapwings increased between one and three years-of-age. The distinct parental roles of the sexes facilitated the occurrence of polygyny by reducing activity-budget costs of polygynous associations for both sexes. Polyterritoriality, polyandry and double-brooding were also recorded and discussed
Insurance Cycles, Spanning and Regulation
This paper offers a novel explanation of the financial underwriting cycle in the property-liability insurance industry. By doing so it resolves that significant anomaly in asset pricing theory posed by cycles in the efficient pricing of insurance coverage. In contrast to the reliance on a variety of institutional or capital market failures underlying all previous explanations of this cycle, we directly augment the complete-markets environment of traditional asset-pricing models through the presence of a single source of risk that cannot be fully hedged through existing financial markets. We realistically interpret this source of risk as unforecastable noise in the implementation of insurance regulations. Cycles in the value of underwriting insurance coverage can arise in this simple variant of a standard complete-markets pricing model owing to the effect of such regulatory risk. We offer a sufficient condition for a stable cycle to endogenously exist in market equilibrium and illustrate this condition in the context of a representative insurance firm and a regulator pursuing a countercyclical policy with noisy implementation. Interestingly, while insurance pricing is efficient in the absence of the regulator, cyclic pricing and underwriting profitability can be induced by a countercyclical regulator policy designed to stabilize the very cycle it creates
The Economic Impacts of the Tobacco Settlement
Recent litigation against major tobacco companies culminated in a Master Settlement Agreement' (MSA) under which the participating companies agreed to compensate most states for Medicaid expenses. We outline the terms of the settlement and analyze whether it was a move toward economic efficiency using data from Massachusetts. Medicaid spending will fall, but only a modest amount ($0.1 billion). The efficiency issue turns mainly on the treatment of health benefits from reduced smoking induced by the settlement. We conclude that the settlement was a move towards economic efficiency.
The Specific Heat of a Trapped Fermi Gas: an Analytical Approach
We find an analytical expression for the specific heat of a Fermi gas in a
harmonic trap using a semi-classical approximation. Our approximation is valid
for kT>hw and in this range it is shown to be highly accurate. We comment on
the semi-classical approximation, presenting an explanation for this high
accuracy.Comment: To be published in Physics Letters A. 7 pages (RevTex) and 2 figures
(postscript
The Self-Dual String and Anomalies in the M5-brane
We study the anomalies of a charge self-dual string solution in the
Coulomb branch of M5-branes. Cancellation of these anomalies allows us to
determine the anomaly of the zero-modes on the self-dual string and their
scaling with and . The dimensional reduction of the five-brane
anomalous couplings then lead to certain anomalous couplings for D-branes.Comment: 13 pages, Harvmac, refs adde
A Review of the "Digital Turn" in the New Literacy Studies
Digital communication has transformed literacy practices and assumed great importance in the functioning of workplace, recreational, and community contexts. This article reviews a decade of empirical work of the New Literacy Studies, identifying the shift toward research of digital literacy applications. The article engages with the central theoretical, methodological, and pragmatic challenges in the tradition of New Literacy Studies, while highlighting the distinctive trends in the digital strand. It identifies common patterns across new literacy practices through cross-comparisons of ethnographic research in digital media environments. It examines ways in which this research is taking into account power and pedagogy in normative contexts of literacy learning using the new media. Recommendations are given to strengthen the links between New Literacy Studies research and literacy curriculum, assessment, and accountability in the 21st century
K\"ahler-driven Tribrid Inflation
We discuss a new class of tribrid inflation models in supergravity, where the
shape of the inflaton potential is dominated by effects from the K\"ahler
potential. Tribrid inflation is a variant of hybrid inflation which is
particularly suited for connecting inflation with particle physics, since the
inflaton can be a D-flat combination of charged fields from the matter sector.
In models of tribrid inflation studied so far, the inflaton potential was
dominated by either loop corrections or by mixing effects with the waterfall
field (as in "pseudosmooth" tribrid inflation). Here we investigate the third
possibility, namely that tribrid inflation is dominantly driven by effects from
higher-dimensional operators of the K\"ahler potential. We specify for which
superpotential parameters the new regime is realized and show how it can be
experimentally distinguished from the other two (loop-driven and
"pseudosmooth") regimes.Comment: 28 pages, v2: added some references, this version matches the
publication in JCA
Two patients with acute thrombocytopenia following gold administration and five-year follow-up
Thrombocytopenia is a well-known side effect following intramuscular gold
therapy in patients with rheumatoid arthritis. Thrombocytopenia may occur
at any time and it can be irreversible and sometimes fatal despite
cytotoxic or immunosuppressive therapy. We describe two patients who
presented with haemorrhagic diathesis on the day after the administration
of aurothioglucose. The thrombocytopenia in these patients was caused by
aurothioglucose-induced antibody-mediated platelet destruction. Both
patients made an uneventful recovery and the platelet count returned to
normal within severa
Further Evidence for Intrinsic Redshifts in Normal Spiral Galaxies
Evidence from galaxy absolute magnitudes, linear diameters, and HyperLeda
images is presented which strongly supports the interpretation that some normal
spiral galaxies can contain large non-cosmological (intrinsic) redshifts in
excess of 5000 km s-1.Comment: 17 pages, Astrophysics&Space Science - Accepted for publicatio
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