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Integrating invasion and disease in the risk assessment of live bird trade.
AimInternational trade in plants and animals generates significant economic benefits. It also leads to substantial unintended impacts when introduced species become invasive, causing environmental disturbance or transmitting diseases that affect people, livestock, other wildlife or the environment. Policy responses are usually only implemented after these species become established and damages are already incurred. International agreements to control trade are likewise usually based on selection of species with known impacts. We aim to further develop quantitative invasive species risk assessment for bird imports and extend the tool to explicitly address disease threats.LocationUnited States of America.MethodsWe use a two-step approach for rapid risk assessment based on the expected biological risks due to both the environmental and health impact of a potentially invasive wildlife species in trade. We assess establishment probability based on a model informed by historical observations and then construct a model of emerging infectious disease threat based on economic and ecological characteristics of the exporting country.ResultsWe illustrate how our rapid assessment tool can be used to identify high-priority species for regulation based on a combination of the threat they pose for becoming established and vectoring emerging infectious diseases.Main conclusionsOur approach can be executed for a species in a matter of days and is nested in an economic decision-making framework for determining whether the biological risk is justified by trade benefits
T-odd correlations in charged Kl4 decays
We analyse the sensitivity to physics beyond the SM of T-odd correlations in
decays, which do not involve the lepton polarization. We show that
a combined analysis of and decays can lead to new
constraints about CP violation in charged-current interactions,
complementary to those obtained from the transverse muon polarization in
and of comparable accuracy.Comment: 6 pages (LaTeX
Economic effects of the Missouri river development program with special reference to Iowa
The erratic flow of the Missouri River creates a severe flood hazard. In 1947 floods caused an estimated total of 111 million dollars\u27 damage in the Missouri River Basin.
In the upper basin the main demands for the waters of the Missouri River and its tributaries are for irrigation and power. In the lower basin the major problems are navigation, protection from floods and power. Wind and water erosion and inadequate industrial development are problems affecting the Basin as a whole. It is important that a program be formulated which will solve the problems enumerated, benefit a large number of people and make the most efficient and economical use of the Basin\u27s resources
The CP-violating asymmetry in \eta\to\pi^+ \pi^- e^+e^-
We study the CP-violating asymmetry {\cal A}_{\rm CP}, which arises, in
\eta\to\pi^+\pi^- e^+e^-, from the angular correlation of the e^+ e^- and
\pi^+\pi^- planes due to the interference between the magnetic and electric
decay amplitudes. With the phenomenologically determined magnetic amplitude and
branching ratio as input, the asymmetry, induced by the electric bremsstrahlung
amplitude through the CP-violating decay \eta\to\pi^+\pi^-, and by an
unconventional tensor type operator, has been estimated respectively. The upper
bound of {\cal A}_{\rm CP} from the former is about 10^{-3}, and the asymmetry
from the latter might be up to O(10^{-2}). One can therefore expect that this
CP asymmetry would be an interesting CP-violating observable for the future
precise measurements in the \eta factories.Comment: LaTeX, 6 pages. One reference corrected, and some new references
adde
Two Welsh surveys of blood lead and blood pressure.
The relationship between blood pressure and blood lead was examined in two population samples. One of these consisted of 1137 men aged 49 to 65 years, the other of 865 men and 856 women aged 18 to 64 years. Neither population had any known important exposure to lead, and the 95% ranges of blood lead levels were 6 to 26 micrograms/100 mL and 6 to 23 micrograms/mL in the men and 5 to 18 micrograms/100 mL in the women. No significant relationship between blood pressure and blood lead was detected in either of the population samples, and the regression coefficients suggest that if there were a real effect, then the mean difference in blood pressure per 10 micrograms difference in blood lead is likely to be 0.7 mm Hg in both systolic and diastolic pressures. In the survey of 1137 men, the rise in blood pressure was measured during the cold pressor test. This test is likely to be affected if lead were to affect neurogenic mediators of blood pressure. The mean change in systolic pressure was 24 mm Hg and the 95% range was -6 to 60 mm Hg, but there was no evidence of any association with blood lead level
Final State Interactions and CP Violation in
Using chiral perturbation theory we calculate the imaginary parts of the form factors that arise from and
rescattering. We discuss their influence on CP violating variables in .Comment: ; 12 pages, 2 figures, TeX format; uses epsf.tex, tables.tex, and
phyzzx.te
Anomalous U(1), holomorphy, supersymmetry breaking and dilaton stabilization
We argue that in certain models with family symmetries the implementation of
the alignment mechanism for the supression of the flavor changing neutral
currents requires mass matrices with holomorphic zeros in the down quark
sector. Holomorphic zeros typically open flat directions that potentially spoil
the uniqueness of the supersymmetric vacuum. We then present an anomalous U(1)
model without holomorphic zeros in the quark sector that can reproduce the
fermion mass hierarchies, provided that is of order one. To avoid
undesired flavor changing neutral currents we propose a supersymmetry breaking
mechanism and a dilaton stabilization scenario that result in degenerate
squarks at and a calculable low energy spectrum. We present the
numerical predictions of this model for the Higgs mass for different values of
and .Comment: 14 pages, no figures; wording of the abstract is change
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