The loss of all deuterium labels from previous feedings of [2-²H]-,
[3,3-²H₂]-, and [2,3,3-²H₃]arginines had indicated the possible intermediacy
of β-hydroxy- and β-ketoarginine (30 and 31, respectively) in the
biosynthesis of the streptolidine portion of streptothricin F (la).
In order to confirm or refute this evidence, D,L-[2,3,3,5,5-²H₅]-
arginine (32) was...
Among the questions that ecosystem-based management raises for economists is how to partition uses of the many biological, chemical and physical attributes of marine ecosystems into sets of property rights that undergird total ocean wealth. An elemental basis of property rights for fisheries involves the interplay between ecological and technological...
Several uranium anomalies, with concentrations of U₃0₈ that
average below 0.003 percent and reach maximums of 0.069 percent,
are associated with black, fossiliferous, pyritic parts of the Ordovician
Ledbetter Slate in northern Stevens County, Washington. The most
uraniferous parts of the slate occur in small (average of 5 by 30...
A publication containing advice on a wide range of gardening topics, including composting, container gardens, fall/winter gardens, fertilizing, insect pests, plant diseases, planting guidelines, raised beds, site selection, slugs, soil improvement, tilling, warm-season crops, watering, and weeds. Includes regional tips for various parts of Oregon.
Metabolomics is a comprehensive analysis of small molecules, or metabolites, in a system. Metabolomics is a hypothesis-generating experiment and offers an unbiased analysis of cell metabolism that can aid in the understanding of fundamental biological processes. Metabolomics is widely and broadly applicable in the biological sciences and has been used...
Obesity is a complex multifactorial disease resulting from excessive energy intake compared to energy expenditure. The excess energy is mostly stored as fat in enlarged adipocytes, but some lipids may infiltrate other organs such as the liver to form ectopic fat. Adipose tissue and ectopic fat produce and secrete a...
This research assessed certain specific plant-soil and community
interrelationships in eastern Oregon habitat types dominated by
subspecies of Artemisia tridentata.
The first evaluation described plant-induced soil chemical patterns for Artemisia tridentata plant communities of high perennial
grass-low shrub and low perennial grass-high shrub composition. Soil
concentrations of total nitrogen, organic...
We investigate the optimal harvesting strategies for McKendrick type population models. Models of this type endow the population with a continuous age structure. They consist of a partial differential equation with a boundary condition which involves an integral of the solution. We study two problems, the first concerns the yield...
As part of investigations to adapt a suitable grazing system in
western Oregon, this research was designed to monitor the effects of
defoliation treatments on dry matter production, forage quality,
regrowth after defoliation, and species composition of a Lolium
perenne Trifolium subterraneum pasture for three consecutive
growing seasons from 1980...
The wind and thermodynamic fields associated with eastern
Atlantic cloud clusters are studied using radiosonde data from
the Global Atmospheric Research Program Atlantic Tropical Experiment
(GATE). These data are from the gridded set of winds prepared
by Dr. Katsuyuki Ooyama (AOML-NOAA) and Dr. Jan-Hwa Chu
(SSEC, University of Wisconsin, Madison)...
Two tributaries of the south fork of the Burnt River, near Unity Oregon were studied
during the summers of 2000 and 2001 to determine water heating and cooling
patterns. Hourly temperature data were recorded for air, water, and soil parameters
at four elevations 150m apart on Barney and Stevens Creeks....
A three-year investigation was conducted during 1980-1982 to
evaluate the potential of using herded sheep as a silvicultural tool
to suppress brush in Douglas-fir (Pseudotsuga menziesii) plantations
of Oregon's Coast Range. Sheep browsing of Douglas-fir was highest
in May soon after bud break. Averaged over the 2 years of grazing,...
The purpose of this study was to compare the accuracy of eight
anthropometric regression equations with hydrostatic weighing for
predicting the percent body fat of adult males with Down Syndrome
(DS). Body fat percentages were predicted for 18 adult males with DS.
Skinfold, circumference, and bioelectric impedance analysis data were...
A mechanism for filiform corrosion of aluminum is proposed
based on experimental evidence and the known aqueous chemistry of
the trivalent aluminum ion. Experimental methods utilized include
autoradiographs with Cl³⁶; pH paper determination of the filiform
head pH; activator concentration and activation period as they affect
filiform growth.
The pH...
Shell-boring polychaetes pose economic risks for oyster aquaculture industries as they reduce the aesthetic quality of oyster products by creating unsightly mud-filled blisters on the inside of the shell. Recently there has been a reported uptick in infested oysters on commercial farms along the west coast of the US, which...
Calcium (Ca) is an essential macronutrient that is increasingly recognized as a biogeochemical factor that influences ecosystem structure and function. Progress in understanding the sustainability of ecosystem Ca supply has been hampered by a lack of information on the various forms and pools of Ca in forest ecosystems. In particular,...
:
_____________________________________________________________________
Steven S. Perakis
Calcium (Ca) is an essential macronutrient that is increasingly
Pacific razor clams (Siliqua patula) are narrow oblong bivalves that can be found in sandy habitats along the western coast of the United States, from Alaska (Aleutian Islands) to southern California (Pismo Beach). In Washington state, the razor clam fishery has been documented to be an important contributor to the...
The competition or rivalry for the use of water resources
among economic sectors of the Pacific Northwest and among geographical
regions of the western United States has intensified in recent
years. This rivalry and the long run prospects for water shortages
have increased the demand for research concerning the productivity...
Concerns about the possible reciprocal differences resulting from
systematic crossings of winter and spring wheat gene pools prompted
this investigation. If traits can be improved by simply reversing the
direction of a cross, then identification of the best female parent in
a cross would be helpful for breeding programs.
Two...
Phytochemicals from the genus, Fagonia, have been attracting increasing attention due to their potential beneficial effects on human health, particularly, anti-cancer properties. Certain Fagonia species contain various types of phytochemicals such as saponins, alkaloids, cardiac glycosides, flavonoids, terpenoids, and tannins. In this study, we investigated the phytochemical composition of a...
The competition or rivalry for the use of water resources
among economic sectors of the Pacific Northwest and among geographical
regions of the western United States has intensified in recent
years. This rivalry and the long run prospects for water shortages
have increased the demand for research concerning the productivity...
Work occupies a considerable amount of time in most peoples’ lives and can be a source of great pleasure or a source of pain. To enhance peoples’ experience at work, we must first understand how to measure and improve the design of work. This research sought to do just that,...
Cuphea is an herbaceous genus having species whose seed
storage lipids are predominantly medium-chain triglycerides (MCTs).
Cuphea lanceolate Ait, and Cuphea viscosissima Jacq. are central to
the breeding of Cuphea as a new commercial source of MCTs. The
objectives of this thesis were to develop a reliable method to
extract...
Cultivated meadowfoam (Limnanthes alba Benth.) is an annual oil seed crop native to southern Oregon. California and British Columbia. The genus Limnanthes is composed of nine species and divided into two sections, Inflexae and Reflexae. The seed oil of meadowfoam is a rich source of erucic acid and several novel...
The cultivated sunflower (Helianthus annuus L., x=17) is one of the most important annual oilseed crops in the world. There are very few publicly shared sequence-based DNA markers and genetic maps in sunflower, even though molecular DNA markers and genetic maps have become widely used in all areas of genetic...
The level of polymorphisms of many biochemical and DNA markers are low in
cultivated sunflower (Helianthus annuus L.). The number of mapped public DNA
markers is limited. Molecular markers have not been developed for the most
important diseases of sunflower, such as downy mildew. The objectives of this
study were...
Nitric oxide (NO) is a signaling molecule that regulates blood pressure and vascular tone. Humans produce NO by endothelial nitric oxide synthase (eNOS), which is impaired in patients with cardiovascular disease leading to increased blood pressure, endothelial dysfunction, and an increased risk of adverse cardiovascular outcomes. Maintaining optimal levels of...
Oxidative stress occurs when the balance between reactive oxygen species and antioxidant defense mechanisms in the body becomes tipped heavily in favor of the reactive oxygen species. Reactive oxygen species can be present in excess due to elevated O2 levels, radiation, infection, smoking, or even excessive exercise. It is also...
Dietary nitrate (NO3-), consumed primarily from leafy green and root vegetables, lowers blood pressure, improves vascular function and aerobic exercise performance. This performance-enhancing effect of nitrate supplementation is largely attributed to the increased bioavailability of the signaling molecule, nitric oxide (NO). Nitric oxide is a ubiquitous free radical signaling molecule...
The oilseed crop Limnanthes alba (white meadowfoam) is grown in Oregon. Methods were developed for the production of a liquid-based bioherbicide from meadowfoam seed meal (MSM). It was determined that glucosinolate-containing extracts of MSM can be combined with active-enzyme-containing liquid extracts of meadowfoam seed to form a fermented product rich...
Obesity is achieved at the point where fat accumulation begins to exert deleterious effects on an organism. The human body accrues fat when there is an energy imbalance occurring, where caloric intake exceeds expenditure.Many anti-obesity drugs used in the past have had undesirable side effects, and currently there is a...
Metabolic syndrome, characterized by a collection of risk factors including abdominal obesity, insulin insensitivity, elevated plasma triglycerides, hypertension and low plasma high-density lipoproteins (HDLs), is a major contributing factor to the development of cardiovascular diseases and type II diabetes (T2D). Xanthohumol (XN), a flavonoid isolated from Humulus lupulus cones, has...
This thesis focuses on the application of the cosmogenic nuclide Beryllium-10 (10Be) in an effort to better constrain the thickness history of the Fennoscandian Ice Sheet (FIS) at the Last Glacial Maximum (LGM) and into the Holocene, as well as begin to answer the long-standing question regarding the age
and...
Meadowfoam (Limnanthes alba Bentham; Order: Brassicales; Family: Limnanthaceae) is a self-compatible, predominantly allogamous, insect pollinated species. Meadowfoam oil is a source of novel unsaturated very-long-chain (VLC) seed oils (C₂₀ and C₂₂) with low concentrations of saturated fatty acids (typically less than 2%) and outstanding oxidative stability. Here we report the...
This dissertation consists of four studies of Populus and Eucalyptus biotechnology and genomic science: 1) induction of floral sterility by tapetal expression of the ribonuclease Barnase in Populus; 2) CRISPR Cas9-mediated gene editing targeting LEAFY (LFY) and AGAMOUS (AG) homologs in Populus; 3) induction of floral sterility by CRISPR Cas9...
Medium chain fatty acids (MCFAs) are important industrial feedstocks for
soaps, detergents and surfactants. Interspecific lines derived from Cuphea lanceolata
and Cup hea viscosissima are being domesticated as a temperate source of MCFAs.
These species also serve as model organisms for understanding the biosynthesis of
MCFAs in seeds. Various markers...
Microsatellites or simple sequence repeats (SSRs) are highthroughput sequence based DNA markers that have been exploited as tools for measuring genetic distance and diversity in evolutionary studies, protection of intellectual property, genetic resource conservation management, cultivar identification and molecular breeding of crop plants. We isolated and sequenced 1095 clones from...
Early studies on the biosynthesis of Sarubicin A, 1, had suggested the
intermediacy of the novel aromatic amino acid 6-hydroxyanthranilic acid,
17. To investigate the biosynthetic steps beyond 17, [¹³C-¹⁵N carboxamide]
6-hydroxyanthranilamide, 27a, was synthesized, and fed to fermentations
of Streptomyces helicus. Incorporation of 27a into 1 provided suggestive
evidence...
Habitat restoration projects are vital for recovering ecosystems, but they can be expensive. One way to help justify the price tag is to value the economic benefits provided by the restored habitat. The issue is that many ecosystem services and the flow of benefits they produce are complex, requiring careful...
Perennial ryegrass (Lolium perenne) - white clover
(Trifolium repens) hill-land pastures were grazed at
different times in the winter to study the effect of time
of winter grazing on plant response and forage production.
The same pastures were grazed by sheep once in early
December, January, February, March, or April...
Government intervention in food grain markets is a common feature of most LDCs. Inasmuch as liberalizing markets is difficult for some of these governments, researchers have offered suggestions to reduce detrimental affects of intervention. The general advice for pricing policy has been for governments to set prices at c.i.f. or...
The goal of this dissertation was to improve our understanding of the physiology and life-history of invasive plants and of the mechanisms underlying life-history trade-offs. I compared invasive and noninvasive species of Rubus (blackberry) that grow together in the Pacific Northwest. Three hypotheses were investigated: (1) Invasive Rubus have higher...