Fuel reduction treatments are being applied to public lands, affecting
significant acreage at considerable expense. This study compares the short term
effects on a chaparral plant community of two different fuel reduction methods, brush
mastication and "hand piling and burning" (HPB). Ceanothus cuneatus dominated
the southwestern Oregon study sites where...
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AN ABSTRACT OF THE THESIS OF
Kendra G. Sikes for the degree of
Measurements of the U₃₇ K’ index and the absolute abundance of alkenones in marine sediments are increasingly used in paleoceanographic research as proxies of past sea surface
temperature and haptophyte (mainly coccolith-bearing species) primary productivity, respectively. An
important aspect of these studies is to be able to compare reliably data...
Childhood obesity has increased dramatically over the last several decades, particularly in industrialized countries, often accompanied by acceleration of pubertal progression and associated reproductive abnormalities (Biro et al., 2006; Rosenfield et al., 2009). The timing of pubertal initiation and progression in mammals is likely influenced by nutritional and metabolic state,...
The sensitivity of the tropics to climate change, particularly the amplitude of glacial‐to‐interglacial changes in sea surface temperature (SST), is one of the great controversies in paleoclimatology. Here we reassess faunal estimates of ice age SSTs, focusing on the problem of no‐analog planktonic foraminiferal assemblages in the equatorial oceans that...
According to the “social intelligence hypothesis,” species with complex social interactions have
more sophisticated communication systems. Giant otters (Pteronura brasiliensis) live in groups
with complex social interactions. It is likely that the vocal communication of giant otters is more
sophisticated than previous studies suggest. The objectives of the current study...
We investigate electron transport properties in large-area, single-layer graphene embedded in dielectric media, using free-space terahertz (THz) imaging and time-domain spectroscopy. Sandwiched between a thin polymethyl methacrylate (PMMA) layer and a Si substrate, graphene layers of different growth recipes exhibit distinctive spatial inhomogeneity of sheet conductivity. The non-contacting, non-destructive THz...
We compared three existing ecoregional classification schemes (Bailey, Omernik, and World Wildlife Fund) with two derived schemes (Omernik Revised and Climate Zones) to explore their effectiveness in explaining species distributions and to better understand natural resource geography in the Klamath Region, USA. We analyzed presence/absence data derived from digital distribution...
For a variety of infectious diseases, the richness of the community of potential host species has emerged as an important factor in pathogen transmission, whereby a higher richness of host species is associated with a lowered disease risk. The proposed mechanism driving this pattern is an increased likelihood in species-rich...
We conducted isothermal (15°C) batch culture experiments with the coccolithophorid Emiliania huxleyi (strain NEPCC 55a) to evaluate the extent to which nutrient and light stress contribute to variability in the alkenone unsaturation index U₃₇ᴷ'. Alkenone content and composition were constant throughout exponential growth in both experiments when nutrients (nitrate and...