Recent developments in handheld computers now make it possible to improve log value recovery by bucking (cross cutting) a tree into log lengths that maximize its value. The use of a handheld computer allows these decisions to be made at the stump for each individual tree. One program developed for...
The four components of the long-term annual mean net surface heating of the tropical Pacific Ocean between 30°N and 40°S are calculated and portrayed. These flux elements were derived by using the bulk formulas and about 5 million marine weather reports for the years 1957–76. In addition to illustrating the...
Epidemics of infectious diseases often occur in predictable limit cycles. Theory suggests these cycles can be disrupted by high amplitude seasonal fluctuations in transmission rates, resulting in deterministic chaos. However, persistent deterministic chaos has never been observed, in part because sufficiently large oscillations in transmission rates are uncommon. Where they...
Epidemics of infectious diseases often occur in predictable limit cycles. Theory suggests these cycles can be disrupted by high amplitude seasonal fluctuations in transmission rates, resulting in deterministic chaos. However, persistent deterministic chaos has never been observed, in part because sufficiently large oscillations in transmission rates are uncommon. Where they...
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Benjamin D. Dalziel1¤, Ottar N. Bjørnstad2, Willem G. van Panhuis3, Donald S. Burke4, C
Epidemics of infectious diseases often occur in predictable limit cycles. Theory suggests these cycles can be disrupted by high amplitude seasonal fluctuations in transmission rates, resulting in deterministic chaos. However, persistent deterministic chaos has never been observed, in part because sufficiently large oscillations in transmission rates are uncommon. Where they...
Numerous evergreen trees and shrubs contain labdane acids, including isocupressic acid, which can cause
late-term abortions in cattle. Recent research has shown that the bark from western juniper trees can
also cause late-term abortions in cattle. Additionally, ranchers have observed that cattle in western juniper-infested
rangelands tend to have decreased...
Rapid hydropower development is occurring in China's Yunnan province in response to increasing clean energy demands, exposing potential vulnerabilities of the area's ecosystems, communities, and geopolitical systems. Here, we present original data on the cultures, economics, hydro-politics, and environments of the Nu River basin, based on household surveys, analysis of...
The bivalve Pacific geoduck (Panopea generosa) has been used in the eastern North Pacific Ocean to create proxies for environmental factors such as temperature and oceanographic conditions. This type of research depends upon accurate age determination of Pacific geoducks, which historically was based on shell growth-increment counts. A recent study...
To predict future coastal hazards, it is important to quantify any links between climate drivers and spatial patterns of coastal change. However, most studies of future coastal vulnerability do not account for the dynamic components of coastal water levels during storms, notably wave-driven processes, storm surges and seasonal water level...
