Proportion data falling in the continuum (0, 1) are very common in practice. It can also happen that an inflated number of zeros (or ones) occur with proportion data. There are extensive studies of zero-inflated data in the literature. Almost all of them, however, focus on zero-inflated count data. Furthermore,...
The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous wells and, since 2004, artificial recharge to the shallow aquifer using infiltration basins. The finite element Integrated...
Krascheninnikovia lanata (winterfat) is a valuable forage species with an
average of 10% crude protein during winter when there are few nutritious options for
livestock and wildlife. However, excessive grazing throughout the west has negatively
impacted survival of winterfat stands. We hypothesized that four years rest from
dormant season livestock...
Pergamasus quisquiliarum Canestini is a polyphagous predatory mite that has been shown to feed on the economically important arthropod, Scutigerella immaculata Newport (Symphyla: Scutigerellidae), Collembola, Diptera larvae, Enchytraeid worms, and miscellaneous other soil organisms. This study examined the feeding behavior of P. quisquiliarum, the effects of cover cropping and tillage...
This research is concerned with the current debate among Oregonians on how to improve the standard of living and accelerate economic development in Oregon. The main question is what economic activities make Oregon, and regions within Oregon grow? To find out where Oregon's economic strength and weaknesses lie, first we...
The 100 North Pacific rockfish species in the genus Sebastes are highly diverse. Rockfishes fertilize their eggs internally and release swimming larvae. Complex courting behaviors may allow female rockfish to be selective about their mates and may promote and maintain speciation. In this study, I applied genetic techniques to survey...
Many agricultural sustainability issues are related to biological processes which are central to the ecological function of soils. Soil physical properties are the architecture in which these processes are carried out. Cover crops hold promise as one of the techniques which can ameliorate poor soil structure and improve bulk density...
Strip tillage is a form of conservation tillage that involves tilling
narrow strips for crop establishment while leaving areas between the strips with undisturbed crop residue. Strip tillage can reduce soil erosion and soil compaction, as well as machinery, fuel, and labor costs. Combined with winter cover crops, strip tillage...
An improved extraction (2.5% HPO₃, 5 mM dithiothreitol) and HPLC quantification using a C-18 column at 35°C and 0.1M acetic acid (98%) and acetonitrile (2%) mobile phase was developed to quantify total ascorbic acid (AA) in commercial whole/semi-skim/skim raw/pasteurized/UHT milk packaged in opaque bags, transparent plastic, cardboard, and Tetra Brik™....