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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

A study of nematode parasites of some California salamanders

Johnston, Herbert Bruce 01 January 1962 (has links)
Little information is available concerning the nematode parasites of salamanders in California. Lehmann (1954) reported the finding of Oxyuris dubia Leidy 1856, in the rectum of 33 Ensatine e. Eschscholtzii from Sonoma County, California, and in 3 of 10 Batrachoseps a. Attenuatus, from San Francisco County, California. He also reported Oxyuris magnivulvaris Rankin 1937 in the rectum of 1 to 2 Aneides flavipunctatus, from Marin County, California and Rhabdias sp., from lungs of 2 of 12 aquatic Triturus torosus from Contra Costa County, California. Lehmann (1960) reported O. dubia from the cloaca of 1 Aneides flavipunctatus and 3 Aneides lugubris taken in Marin and Sonoma Counties, California. Several similar studies have been made in other states citing the occurrence of nematodes in various species of salamanders. There is an even greater paucity of information concerning parasitism in those salamander species inhabiting the western slope of the Sierra Nevada. This investigation is concerned with the four most common salamanders of the central California clopes, Aneides lugubris Hallowell, Batrachoseps attenuatus attenuatus Eschscholtz, Ensatina eschscholtzii platensis Espada, and Taricha torosa sierrae Twitty. Individuals of these species were collected and examined for parasites over the fall, winter and spring months, commencing in the fall of 1960 and extending through the spring of 1962. Data were collected to determine what nematode species inhabit these hosts and to ascertain the incidence and sites of infection. An attempt was also made to determine whether time of year, environmental conditions, and geographic distribution are of particular significance in the host-parasite relationships studied. A second group of salamanders which included Aneides lugubris Hallowell and Taricha torosa Rathke was examined. Both of these species were taken in a coastal region and were used as a comparison group Special attention has been directed to the study of Oxyuris dubia Leidy, 1856, with the intent of clarifying Leidy’s description of this species. This nematode is a frequent parasite of the salamanders studied, and special consideration has been given to the culturing of their eggs in an attempt to better understand the pattern of development.
162

The diversity of arthropods in the surface soil layers of an old-growth redwood forest

Horner, Kimberley Jane 01 January 1993 (has links)
The abundance and diversity of arthropods present in the surface soil layers at various forest sites in northern California were investigated, primarily at two old-growth redwood forest sites in Prairie Creek Redwoods State Park and Jedediah Smith Redwoods State Park. A wide variety of arthropods were found, including representatives of Araneae, Pseudoscorpiones, Opiliones, Acarina, Isopoda, Diplopoda, Chilopoda, Symphyla, Pauropoda, Protura, Diplura, Collembola, Thysanoptera, Hemiptera, Coleoptera, Diptera, and Hymenoptera. Arthropod densities were significantly higher in the wet than in the dry period, indicating seasonal variation in surface densities of soil arthropods. The densities of arthropods in soils collected from beneath coast redwood (Sequoia sempervirens) and western hemlock (Tsuga heterophylla) trees were not significantly different.
163

A history of the flood problem in the Marysville-Yuba City area, with special reference to the Great Flood of 1955

Dunlop, David Karl 01 January 1963 (has links) (PDF)
The water problem in the Sacramento Valley, prior to it occupation by the white race, is impossible to ascertain. The Indians, however, have a tradition of a great flood sometime in the early part of the nineteenth century, which inundated the whole valley and in which a great many lives were lost and villages destroyed. It forms an era in their calendar from which they date events. Again a great flood in the winter of 1825-26 is mentioned, through an Indian named Peter. He used to say that the trapping party he was with was compelled to camp in the Buttes on account of high water, and that those hills were full of grizzlies, elk, antelope, and smaller game that had taken refuge there.
164

Development of California municipal recall law

Chapman, Jere Wilbur 01 January 1972 (has links)
In California municipal politics recall has played a conspicuous role. It has consistently served as a source of controversy whenever it is undertaken. While it is a principle inspired by the direct democracy campaign of the California progressives in the early twentieth century, it remains as an evolving legal process and dynamic political issue within the context of California political history.
165

Closing the Achievement Gap: A Case Study of One High-Performing Public Elementary Charter School Supporting Historically Marginalized Students

Joyce, Liam J. 01 January 2009 (has links) (PDF)
Historically marginalized students (HMS), defined for the purposes of this study as Latino, African American, and English Language Learners, in low-performing and low-socioeconomic schools (those usually with a high percentage students receiving free or reduced-price lunch) have received significant attention and research over the years. However, little attention has been paid to minority students at otherwise high-performing (mostly Caucasian) schools. Research suggests an achievement gap between HMS and Caucasian and Asian students. This case study sought to identify strategies to remedy this academic achievement gap. The focus of this study was the academic performance of HMS in a suburban setting. To better understand how a high-performing school affects academic performance by HMS, the researcher examined the classroom environment, teacher instructional strategies, leadership practices, and school support services of one such school. This study used a case study format to examine a suburban elementary charter school within an urban school district. The study specifically investigated the language arts instruction of two fourth- and two fifth-grade classrooms. These grade levels were selected due to evidence that the achievement gap begins to widen at this point in HMS school careers and continues through the 12th grade. Three data collection methods were used: (a) a document review of current fourth- and fifth-grade language arts curricula, (b) classroom observations conducted to identify teacher instructional strategies that support HMS, and (c) interviews with four teachers and two administrators after the observations. Known strategies that have positively influenced the achievement of historically marginalized students include equitable classroom instruction, positive teacher-student relationships, culturally relevant practices, a nurturing school culture, directed teacher professional development, and strong school leadership. The study sought to identify differentiated positive classroom environments, current use of teacher instructional strategies, elements of strong leadership practices, and implementation of school support services that foster academic achievement by HMS.
166

Paleomagnetism of Miocene Volcanic Rocks in the Mojave Region of Southeastern California

Acton, Gary Dean January 1986 (has links)
Paleomagnetic data were collected from Miocene volcanic rocks in the Turtle Mountains, Clipper Mountain, Colton Hills, and Piute Range of the southern Basin and Range (SBR) province in southeastern California as well as in the Soledad Mountains of the Mojave block in southern California. The data from these two tectonic provinces yield significantly different paleomagnetic directions, which probably indicates the existence of a major crustal and /or lithospheric discontinuity in the area between the Barstow Basin and the Clipper Mountain. Comparing the mean direction from the SBR data to the Miocene expected direction indicates no statistically significant rotation (R = -0.2° ± 18.2°) or flattening (F = -6.5° ± 9.2°). A similar comparison for the Soledad Mountain data, which were combined with data of Burke et al. (1982) from the Barstow Basin, yields a significant rotation of -43.5° ± 12.9° and flattening of 19.3° ± 10.6° for the Mojave block. These Mojave block values may be exaggerated a few degrees due to inadequate averaging of secular variation and possible improper structural corrections.
167

The potential dangers of sexually oriented businesses

Martinez, Phillip January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture/Regional and Community Planning / John W. Keller / An ongoing debate has taken place within the criminology and planning sectors. A major question that has been raised is, "Are sexually oriented businesses associated with high crime rates?" Though this may seem like an important topic for communities, there is currently a lack of empirical studies dealing with it. This report acts as a case study for San Francisco, California. The case study compares crime rates near ten strip clubs with crime rates to a fairly similar business, night clubs. The data that was used refers to crime that took place from 2012-2014, and includes most violent, property and public disorder crimes. In order to find out which type of business is more "dangerous", a percentage equation was used. The results from the percentage equation show the probability of crime incidents within 1,500 feet of a strip club or a night club. An example of a result from this equation is that on average, 3.67% of all of San Francisco’s "Public Drunkenness" incidents will take place within 1,500 feet of a night club. Meanwhile, 4.54% of San Francisco’s "Public Drunkenness" incidents will occur within 1,500 feet of a strip club. One can see that each business has its own percentage based off of public drunkenness crimes that occurred from 2012-2014. A GIS spatial analysis process, the Ordinary Least Squares (OLS), was also used. The OLS process factors crimes with demographics. This is useful for criminological studies because it can find a statistically significant relationship between things like assaults and the percentage of people living in poverty. The crimes were arranged in 18 categories ranging from kidnapping to domestic violence, from larceny to arson, etc. Results show that when viewing the numbers from the percentage equation, night clubs had higher percentages for 6 of the 18 crimes. The strip clubs showed higher percentages for the remaining 12 crime categories. When viewing the results from the GIS analysis, one can see if crime rates are determined by characteristics such as income, percentage of people receiving food stamps, proximity to strip clubs and more. This report will cover background literature regarding sexually oriented businesses. It will also show the methodology used for the San Francisco case study, as well as the results from the study.
168

Stories from a Golden State

Paul, Sara R. 20 December 2013 (has links)
No description available.
169

Currents and water masses at the entrance to the Gulf of California, spring 1970

Alvarez Sanchez, Luis Gustavo 12 August 1974 (has links)
Hydrographic data and drogue observations were used to describe the circulation and water masses in the upper 500 meters of the region of the entrance to the Gulf of California in the early spring of 1970. The thermohaline structure of the water and the general circulation in the vicinity of the entrance to the Gulf of California indicated that four water masses were present. California Current water on the western side of the entrance, Subtropical Surface water in the middle part and Gulf water on the eastern side. Underlying these three waters, Subtropical Subsurface water was found from about 150 to 500 meters. The geostrophic calculations indicate that a broad region of outflow from the Gulf existed on the eastern side associated with a marked upward displacement of isopycnals towards the east. Speeds were near 30 cm/sec at the surface and decreased to less than 3 cm/sec at 300 meters. Outflow also occurred on the western side, near the Baja California coast, at lower speeds. Inflow to the Gulf was observed near the middle part of the entrance at speeds of 30 to 40 cm/sec at the surface, decreasing to less than 6 cm/sec at 300 meters. The drogue observations were in agreement with the general circulation pattern inferred from geostrophic currents. Drogue and geostrophic velocities showed agreement better than 70% at 10 and 50 meters. The decrease of geostrophic velocity with depth indicates that a baroclinic condition existed. Comparison of these velocities with the drogue measurements indicates that the baroclinic circulation was predominant in the upper 100 meters. In the upper 150 meters the low salinity water from the California Current was flowing into the Gulf. The high salinity Gulf water was found in the regions of outflow as to be expected to avoid accumulation of salt inside the Gulf by strong evaporation. / Graduation date: 1975
170

Crustal structure and faulting of the Gulf of California from geophysical modeling and deconvolution of magnetic profiles

Doguin, Pierre 09 June 1989 (has links)
Using gravity, magnetic, bathymetric and seismic refraction data, I have constructed a geophysical cross-section of the central part of the northern Gulf of California. The section exhibits a crustal thickness of 18 km and features an anomalous block of high density lower basement (3.15 g/cm³) which probably resulted from rifting processes during the opening of the Gulf. The magnetization of the upper basement ranges from 0.0005 to 0.0030 emu/cm³. Three different layers of sediments are modeled, ranging from unconsolidated (1.85 g/cm³) to compacted (2.50 g/cm³). I present a deconvolution method for automated interpretation of magnetic profiles based on Werner's (1953) simplified thin-dike assumption, leading to the linearization of complex nonlinear magnetic problems. The method is expanded by the fact that the horizontal gradient of the total field caused by the edge of a thick interface body is equivalent to the total field of a thin dike. Statistical decision making and a seven point operator are used to insure good approximations of susceptibility, dip, depth, and horizontal location of the source. After using synthetic models to test the inversion method, I applied it to the Northern Gulf of California using data collected in 1984 by the Continental Margins Study Group at Oregon State University. Fault traces, computed by the deconvolution, are plotted on a map. The faulting pattern obtained is in good agreement with that proposed by other workers using other methods. The depths to the top of the faults range from 4 to 5 km in the eastern part of the Gulf, where they may be interpreted as the top of the structural basement. Deeper estimates are obtained for the western part of the Gulf. / Graduation date: 1990

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