30 research outputs found
A study of the Delegation of Administrative Authority to the Superintendent by the Board of Education in Nine Southwestern Iowa Communities
The main purpose of the study was to determine the division of executive authority and the responsibility for its use between the superintendent and his board of education in small southwestern Iowa towns. This problem was found to involve four facets: 1. the determination of the executive authority which the board of education delegates to the superintendent of schools; 2. the determination of the amount of executive authority which the board of education shares with the superintendent of schools; 3. the determination of the authority which the board of education retains; 4. the determination of the amount of responsibility for the use of executive authority which the board of education assigns the superintendent of schools as the results of the executive authority which it delegates to him or shares with him
Generalized Fibonacci Numbers and Blackwell's Renewal Theorem
We investigate a connection between generalized Fibonacci numbers and renewal
theory for stochastic processes. Using Blackwell's renewal theorem we find an
approximation to the generalized Fibonacci numbers. With the help of error
estimates in the renewal theorem we figure out an explicit representation
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Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska
Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set of key traits and universal system of trait measurement. Many recent studies hypothesize global generality of trait patterns, which would allow for comparison among ecosystems and biomes and provide a foundation for general rules and theories, the so-called “Holy Grail” of ecology. However, the majority of these studies focus on functional trait patterns of vascular plants, with a minority examining the patterns of cryptograms such as lichens. Lichens are an important component of many ecosystems due to their contributions to biodiversity and their key ecosystem services, such as contributions to mineral and hydrological cycles and ecosystem food webs. Lichens are also of special interest because of their reliance on atmospheric deposition for nutrients and water, which makes them particularly sensitive to air pollution. Therefore, they are often used as bioindicators of air pollution, climate change, and general ecosystem health. This thesis examines the functional trait patterns of lichens in two contrasting regions with fundamentally different kinds of data.
To better understand the patterns of lichen functional traits, we examined reproductive, morphological, and chemical trait variation along precipitation and temperature gradients in Oregon. Specifically, we measured traits of 102 macrolichen species collected from 166 USDA Forest Service program for Forest Inventory and Analysis (FIA) plots. These plots were located in a more-or-less continuous swath across Oregon between 43°W and 45°W. Plots were grouped into seven regions (the Oregon Coast, Coast Range, Willamette Valley, Western Cascades, High Cascades, Eastern Cascades, and Eastern Oregon). Using multivariate analysis techniques we found strong linear and nonlinear trait patterns along precipitation and temperature gradients, and were able to characterize the seven main regions of Oregon by the relative abundance of lichen traits.
The literature on what lichen traits are most common in which habitats is sparse and anecdotal; understanding trait-habitat patterns could have management implications due to lichen importance as bioindicators and animal forage. Understanding how key traits are distributed among habitats could provide insight into potential air pollution impacts on certain habitats, animal movement among habitats, etc. To examine trait-habitat patterns, we measured the reproductive, morphological, and chemical traits of 429 lichen species collected haphazardly (without a formal sampling framework) from ten distinct habitats within Katmai National Park in southwest Alaska as part of a taxonomic inventory. Using multivariate analysis techniques we grouped habitats based on the expression of lichen traits and described the relative abundance of each trait in different habitats. The second goal of this study was to examine the potential usefulness of herbarium collections in ecological studies of this type. Herbarium specimens are a large potential resource that is generally unused in ecological studies due to concerns over potential bias and noise introduced by variation in collection methods. However, recent work has suggested that herbarium specimens may yield more useful results than previously thought and could be a valid resource for ecological studies. The data for our study were collected in a haphazard manner for a floristic inventory, similar to the collection methods used for many herbarium specimens. The patterns that we observed indicates that herbarium specimens may be a good resource for future research
Galaxy Clusters Associated with Short GRBs. II. Predictions for the Rate of Short GRBs in Field and Cluster Early-Type Galaxies
We determine the relative rates of short GRBs in cluster and field early-type
galaxies as a function of the age probability distribution of their
progenitors, P(\tau) \propto \tau^n. This analysis takes advantage of the
difference in the growth of stellar mass in clusters and in the field, which
arises from the combined effects of the galaxy stellar mass function, the
early-type fraction, and the dependence of star formation history on mass and
environment. This approach complements the use of the early- to late-type host
galaxy ratio, with the added benefit that the star formation histories of
early-type galaxies are simpler than those of late-type galaxies, and any
systematic differences between progenitors in early- and late-type galaxies are
removed. We find that the ratio varies from R(cluster)/R(field) ~ 0.5 for n =
-2 to ~ 3 for n = 2. Current observations indicate a ratio of about 2,
corresponding to n ~ 0 - 1. This is similar to the value inferred from the
ratio of short GRBs in early- and late-type hosts, but it differs from the
value of n ~ -1 for NS binaries in the Milky Way. We stress that this general
approach can be easily modified with improved knowledge of the effects of
environment and mass on the build-up of stellar mass, as well as the effect of
globular clusters on the short GRB rate. It can also be used to assess the age
distribution of Type Ia supernova progenitors.Comment: ApJ accepted versio
The epidemiology of coronary heart disease : A review
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31999/1/0000041.pd
Community Breeders: Animal Husbandry in Portlandia
A brief exploration of animal husbandry within the city limits of Portland, Oregon, covering residents\u27 experiences with raising chickens, goats, bees and other farm animals. Touches on new concerns relating to local sources for food, community building, and drawbacks faced by some residents
Taxonomic and Functional Beta Diversity in a Forest Mosaic and Its Implications for Community Assembly
Color poster with text, photographs, and charts.Understanding the processes that shape community
assembly is one of the key goals of ecology. One possible mechanism of assembly is deterministic assembly, in which species traits determine their ability to establish and persist in a location; lack of resources, predation and disturbance
are all thought to lead to deterministic assembly. Alternatively, there is stochastic assembly, where community assembly is virtually random. The purpose of this study was to examine beta diversity, which is the variation that exists between two or more communities, to determine which assembly process is present in a given community.University of Wisconsin--Eau Claire Office of Research and Sponsored Programs
Freezing! Thawing! Waves! Talk About Stress... Exploring the Effects of Biological Filters on Lichen Populations in the BWCAW
Color poster with text, images, maps, and graphs.This study examined the effects of biological filters on lichen populations in the Boundary Waters Canoe Area Wilderness (BWCAW).University of Wisconsin--Eau Claire Office of Research and Sponsored Program