The hemlock woolly adelgid, Adelges tsugae, is causing widespread mortality of eastern hemlock, Tsuga canadensis, in the eastern United States. In the West, A. tsugae causes negligible damage to western hemlock, Tsuga heterophylla. Host tolerance traits and presence of endemic predators may be contributing to the relative tolerance of western...
The main purpose of this study was to investigate and describe strategies that Thai ninth grade students use to solve algebra word problems. The second purpose of this study was to investigate teachers' instruction during word problem solving lessons. Three mathematics teachers and one of each of their classes participated...
Pheromones are chemical cues produced by organisms that affect the behavior and/or physiology of conspecifics. The orchestration of reproductive behaviors in many animals depends on the expression of sex pheromones. In insects, intraspecific variation in sex pheromone expression is commonly observed and often influences social interactions between individuals. To what...
Reported here is an investigation to determine the in vitro and in vivo metabolism
of xanthohumol (XN). XN is the major prenylated flavonoid of the female
inflorescences (cones) of the hop plant (Humulus lupulus). It is also a constituent of
beer, the major dietary source of prenylated flavonoids. Recent studies...
Relay strip-cropping combines two vegetation management tactics, under-sowing
and strip-management. In this study conducted from 1994 though 1997, a
cover crop seed-mixture containing oats (Avena sativa L. var. "Monida"), common
vetch (Vicia sativa L.), red clover (Trifolium pratense L.), annual ryegrass (Lolium
multflorum Lam.), and buckwheat (Fagopyrum esculentum Moench) was...
Summer drought is a major factor limiting the regrowth of perennial ryegrass seed crops. This phase of crop development has a strong influence on seed yield because most of the tillers that contribute towards next season's seed crop are produced or regrown during this period. In recent years many seed...
The (nonlinear) response behavior of a piecewise-linear system is investigated under
both deterministic and stochastic excitations in this study. A semi-analytical procedure is
developed to predict the system behavior by evaluating the joint probability density functions
of the Fokker-Planck equations of the stochastic piecewise-linear system under random
excitations via a...
With the rapid increase of the world energy demand and
consumption, the method and techniques to analyze, improve
and optimize energy conversion systems have to deal not only
with direct fuel exergy (energy) consumption, but also with
other resources, which have associated exergy consumptions,
and with environmental impacts, such as...
Stochastic analysis procedures have been recently applied to analyze nonlinear
dynamical systems. In this study, nonlinear responses, stochastic and/or chaotic, are
examined and interpreted from a probabilistic perspective. A multi-point-moored
ocean structural system under regular and irregular wave excitations is analytically
examined via a generalized stochastic Melnikov function and Markov...