Arthropod communities in pear are conceptualized as hierarchically
organized systems in which several levels of organization or subsystems
can be recognized between the species population level and the community
as a whole. An individual tree is taken to be the community habitat with
arthropod subcommunities developing on leaf, fruit and...
The focus of this thesis is to design, characterize, and apply novel computational methods and molecular systems to interrogate heterogeneous human gut microbiome-related phenomena. In Chapter 2, I design, implement, and characterize a method for embedding co-occurrence patterns derived from massive 16s amplicon datasets. I use this method to 1....
Microscopic organisms inhabit virtually every niche on this planet, where they perform functions vital to all life on earth. Accordingly, humans host a complex community of microorganisms (i.e. the gut microbiome) that inhabit the gastrointestinal tract and modulate host physiology. Insight into the specific mechanisms through which gut microbes influence...
This dissertation consists of two articles to be submitted for publication. The first,
a literature review, makes visible common influences on science teaching self-efficacy
beliefs and also points to potentially invisible validation concerns regarding the
instrument used. The second investigates the participants' invisible science teaching self-efficacy
beliefs and, through the...
Agricultural and companion animals are integral to our way of life as they provide us with nourishment, financial resources, transportation, and companionship. However, pets, managed animals in the agricultural industry, as well as wild populations of food animals are all subject to health and mortality risks. The gut microbiome is...
Freeze/thaw cycles are numerous in agricultural soils of the Pacific Northwest. Potential loss of soil by erosion is high whenever a soil thaws from the surface creating a saturated soil overlying an impermeable frozen layer. Field studies were conducted to investigate the effect of surface residue on soil freezing. Residue...
Because of the fuel crisis and problems associated with thermal
pollution there is new impetus and urgency for developing more
efficient energy conversion systems for power generation. A preliminary
analysis was undertaken to determine the potential of staged
Rankine cycle systems for substantially higher efficiency. It was
necessary to optimize...
Studies of anisotropic and isotropic Raman line shape yield information about the rotational motion (rotational correlation function) and non-reorientational (vibrational) lifetimes. The rotational motion of carbon disulfide has been studied previously by the techniques of Raman spectroscopy (6, 43), Rayleigh scattering (43, 46) and direct measurement (47). This work was...
This analysis is the study of Oregon's wildlife resources from
the period prior to white settlement up to the present time, including
critical projections, based on present trends and expected conditions
for both human and wildlife populations in the state up to the year 2010.
Prior to white settlement Oregon...
Gaseous transport through soil in the presence of soil
microorganisms has been investigated. More recently, modeling of
gaseous transport in the unsaturated zone has been investigated.
However, the problem of mathematical model of oxygen and carbon
dioxide transport through soil, as affected by the climatic
conditions, the transport of soil...
The purpose of this study was to develop a valid and reliable
instrument to measure the organizational climate of the community
college as perceived by community college administrators, faculty, and
classified staff.
There were three phases in this study. The first was to develop a
pool of test items based...
Forest soils with low bulk densities are often considered less
susceptible to compaction than soils with higher bulk densities. The
objective of this study was to determine if soil strength controlled the
compression of soils with low bulk density. Four soils were selected
for this evaluation. Three of these were...
Experiments were conducted to study the effect of pore size
distribution on the diffusion of 2, 4-Dichlorophenoxyacetic acid (carbon-
14) through water saturated porous media. Eight size fractions of
glass beads were used representing the porous media. It was found
that as the average particle radius, and hence pore radius,...
Temperature and water potential effects on the growth,
transpiration, total nonstructural carbohydrate (TNC) content, and
nutrient uptake of sudangrass (Sorghum vulgare var. piper) were
investigated in laboratory experiments. The effect of nitrogen supply
on the growth and nutrient uptake at constant soil water potential was
also investigated in this study....
All mammals host communities of commensal microbes in and on their bodies. Recent technological advances, combined with experimental studies in laboratory animals, are beginning to reveal the ubiquitous links between the gut microbiome and host disease, metabolism, immunity, and numerous other host functions. A new challenge of microbiome research is...
In higher vertebrates, normal digestion and absorption by the
gastrointestinal tract are dependent on the orderly and controlled
transit of intraluminal contents. A relationship between fluid
passage through the gut and absorption from the gut has yet to be
examined in fish. In marine teleosts, the osmolality and ion concentration...
The purpose of this study was to determine if
students' school-related attitudes are significantly
affected by teacher classroom discipline management based
upon concepts contained in Judicious Discipline: A Constitutional
Perspective for School Rules (Gathercoal, 1986).
The data relative to student school-related attitudes
of elementary, middle, and high school students toward...
Over the past twenty years, the national three-year graduation rate for community college students has ranged from 44% to roughly 31% in 2013 (NCES, 2013). As a way to address such low graduation rates, colleges have implemented a myriad of services and programs (i.e., tutoring, mentoring, etc.). Another intervention is...
Purpose of the Study
The study was designed to determine whether the amount of
formal education industrial education teachers have completed does
affect their (1) attitude toward teaching and (2) performance in the
classroom. The specific questions formulated to investigate this research
were:
1. Will the amount of formal education...
Recent trends in higher education have led to the development of
alternatives to traditional on-campus graduate degree programs. There is a
concomitant need to understand student experience in field-based programs
which support continuing education and career development for employed
adults. The central purpose of this research was to explore the...
Purpose of the Study
The purposes of this study were to (1) identify the educational
and socioeconomic characteristics of Latin American students who
have graduated from the California State College system, (2) to identify
those characteristics which significantly affect academic success,
utilization of training and return home to Latin America...
Purpose of the Study
The purpose of this study was to determine and analyze criteria
and procedures used in the selection of occupational advisory committee
members in Oregon community colleges. The existence of a
common core of criteria and procedures for selecting occupational
advisory committee members was investigated. Further, the...
The influence of boundary layer pumping on an externally-forced
synoptic-scale flow is examined. The results follow earlier theories of
stratified incompressible Boussinesq flow. These theories state that
the spin-down time scale and the penetration depth of the influence of
boundary layer pumping are inversely proportional to the stratification
and directly...
Purposes of the Study The study had several purposes, the major one being to
determine the common professional education competencies needed by
community college instructors of trade and industrial education. Two
other purposes of the study were to determine if differences existed
among community colleges according to scores trade and...
The study was designed to determine if students using the individualized
instruction method, scored significantly higher on a 30 question
achievement test than did students in more traditional group paced
programs. The study also attempted to determine if attitudes displayed
by educators, as measured on an attitude scale, aided in...
Purpose of the Study
The purpose of this study was (1) to identify the educational and
socio-economic characteristics of enrollees in the In-School Neighborhood
Youth Corps Program and (2) to determine those educational
and socio-economic characteristics that would predict potential achievement
in the In-School Neighborhood Youth Corps Program.
Procedures
A...
The purpose of this study, to examine the relevance of U.S.
graduate education in agriculture to careers in agricultural
development of East African agriculturalists, was examined in
terms of three problems:
Problem 1: Was U.S. graduate education in agriculture
relevant to careers in agricultural development of East
African agriculturalists?
Problem...
This qualitative study describes and interprets the interactions of participants in a
community college writing class delivered by computer-mediated communication
(CMC). The class represented a best practice model of learner-centered instruction in a
CMC class. The description and the discussion are framed by five aspects of CMC
instruction: (1) context;...
The purpose of this study was to improve instructional system design at Small
Business Development Centers by developing a best practice model for assessing client
training needs. Two research questions were addressed:
1. Is self-directed learning an appropriate framework for instructional system design at
Small Business Development Centers?
2. What...
The principles of continuum mechanics provide a consistent
framework for the derivation of mathematical statements describing
transport of water and solute, and growth in plant tissue. These
derivations are based upon the explicit consideration of the tissue as
a mathematical continuum composed of a cell wall matrix, water, and
solute...
Teacher efficacy continues to be an important area of study in educational research. This study tested an instrument designed to assess the perceived efficacy of agricultural education teachers when engaged in lessons involving mathematics instruction. The study population of Oregon and Washington agricultural educators utilized in the validation of the...
The purpose of this study is to explore through their own stories and journeys (storjourns), how lesbian leaders influence and transform dominant community college culture. Five lesbian leaders participated who held the position of Director, Associate Dean, Dean, Executive Vice President, and President/Executive Dean. This microethnographical inquiry divulges and makes...
Wave dispersion and fracture are phenomena that involve. mechanisms triggered at the scale of a material's internal structure. Experiments were performed with a candidate material to judge the hypothesis that wave dispersion measurements can be used to nondestructively predict fracture strength. Wood-based particleboard was chosen as the candidate material because...
Osteoporosis is a common metabolic bone disease, affecting a third of women and a fifth of men over age 65. In the US, annual health care costs associated with osteoporosis are estimated to be over $20 billion. Osteoporosis is associated with increased fracture risk, which has been demonstrated to predict...
The purpose of this study was to determine the importance and
the frequency of use of certain communication skills to job-entrylevel
mechanics as assessed by employers, educators at various levels,
and entry-level industrial mechanics. The study was conducted in
Lane County, Oregon. Communication skills investigated for importance
and for frequency...
The purpose of this study was to determine the concerns of past participants of the Summer Agriculture Institute regarding the use of agriculture as a context for teaching and to determine how they implement curriculum integration. The study used the Concerns-Based Adoption Model as a theoretical framework, which resulted in...
The continuum theory provides a framework in which the growth
of a plant root as a dynamic process involving interactions among
transport of water and solute, cell division, and the subsequent cell
elongation can be described. A plant root is modeled as a one-dimensional,
multi-phase, mathematical continuum. The network of...
Sudden changes occur where the mean values associated with two adjacent non-overlapping
windows of data are anomalously different, and the transition between the
window means occurs over a scale that is small relative to the scale of the windows.
Positions of sudden changes can be economically retrieved. The sudden change...
Atmospheric boundary layers become stably stratified at night over land when the surface becomes colder than the air layer above. In stable nocturnal boundary layers (SNBL), turbulence becomes weak and intermittent, terrain-induced phenomena such as drainage currents or gravity-waves emerge and the surface heterogeneity is enhanced. Because of their complexity...
Gamma-gamma directional correlations were measured
in Ba¹³⁴ at ten angles between 90 degrees and 180 degrees in ten
degree increments using a scintillation spectrometer. The spectrometer
which used NaI crystals, differential energy selection,
and standard coincidence techniques was tested by measuring the
directional correlation of the two cascade gamma rays...
The very stable boundary layer is a region of the atmosphere typified by large
vertical gradients of temperature and momentum. Analysis of very stable atmospheric
flows is complicated by the presence of nonlinear interactions among gravity waves, shear-driven
overturning circulations, two-dimensional vortical modes and intermittent turbulence
in various stages of...