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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.
1

Extending Raman spectroscopy to the nanoscale

Lee, Nam-Heui 02 October 2007 (has links)
No description available.
2

Spatial Analysis of Atrazine in the Elm Fork Watershed

Ochandio, Mario Roberto 05 1900 (has links)
This study assessed the water quality of the Elm Fork Watershed with regards to the herbicide Atrazine. Atrazine is a potential environmental endocrine disruptor and carcinogen. Overall, concentrations were lower than the four-quarter drinking water average of 3 µg/Lthe Maximum Contaminant Level set by the USEPA. However, three creek stations had four-quarter average concentrations greater than 3 µg/L, and virtually all samples exceeded the 0.1 µg/L standard set in Europe [1,2]. Statistically significant differences in concentrations were detected between the 27 sampling stations and areas of high concentrations were identified. However correlations between Atrazine concentrations and land-use and precipitation were not statistically significant. Further analysis with more detailed data should be conducted before any relationships are discarded.
3

Vertebrate Survey of Rocky Fork Wildlife Management Area, Unicoi and Greene Counties, Tennessee.

Welch, J. Michael 01 August 2001 (has links)
The most prominent cause of habitat fragmentation is intensification of human land use. Negative effects of large-scale forest fragmentation have been documented in most vertebrate classes. The inherent problem in directly documenting effects lies in our ignorance of historical community structure. Information from this study provides baseline data on vertebrates within threatened habitat. This privately-owned block of uninterrupted forest has never been systematically surveyed by biologists. Changes in ownership have placed the integrity of this interior forest habitat in doubt. This research may provide the foundation for long-term studies of the effects of fragmentation within forests of the Southern Appalachians. A total of 50 visits were made between April 1998 and July 2000. Documentation of 109 species of vertebrates was established, representing 4 reptile species, 19 amphibian species, 72 bird species, and 12 mammal species. Although no procedure for documenting fishes was implemented, 2 species from this class were identified.
4

Spatial variation in brook trout (Salvelinus fontinalis) population dynamics and juvenile recruitment potential in an Appalachian watershed

Liller, Zachary W. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 132 p. : ill., maps. Vita. Includes abstract. Includes bibliographical references.
5

The Use of a Tuning Fork and Stethoscope Versus Clinical Fracture Testing in Assessing Possible Fractures

Moore, Michael Bryan 13 April 2005 (has links)
Traditional fracture testing in the field of athletic training relies heavily on subjective responses of the athlete. Percussion and compression type tests rely on the athlete stating an increase in pain which represents a positive symptom of a possible fracture. The tuning fork and stethoscope method relied purely on a subjective assessment from the examiner. The purpose of the study was to determine if the use of a 128Hz tuning fork and stethoscope were effective evaluation tools in the assessment of possible fractures as compared to the traditional fracture tests that are used in the athletic training field. A vibrating 128 Hz tuning fork was placed on the bone/area where swelling was minor to facilitate good cortical bone contact. Then the conical bell of a stethoscope was placed on the opposite end on the bone or bones. A diminished sound arising from the injured bone as compared to the uninjured represented a positive sign for a possible fracture. Traditional fracture testing was performed and noted. An x-ray, diagnosed by an orthopedic physician, supported the validity of the tuning fork and traditional fracture testing methods. The attempt was to see what testing method, the tuning fork and stethoscope or traditional fracture testing, was a more valid evaluation tool when it comes to fractures. This study was performed at a university's athletic training room and a local orthopedic center. The study consisted of any subject between the ages of 18-85 that presented with a suspected fracture at either testing facilities. The current study examined 37 male and female subjects whose age ranged from 18-85 years old. The long bones that were tested in this research were as follows: the phalanges of the hand and foot, metacarpals, metatarsals, humerus, radius, ulna, fibula (including the lateral malleolus), and tibia (including the medial malleolus). The tuning fork and stethoscope was shown to be an effective and valid tool for evaluating possible fractures by yielding a success rate of 89.2% when compared to an x-ray. The percussion and compression fracture testing methods yielded only a success rate of 67.6% and 64.9% respectively. / Ph. D.
6

Source and occurrence of placer gold in central Ross County, Ohio

Smith, Kelly C. January 1992 (has links)
No description available.
7

Highly available storage with minimal trust

Mahajan, Prince 05 July 2012 (has links)
Storage services form the core of modern Internet-based services spanning commercial, entertainment, and social-networking sectors. High availability is crucial for these services as even an hour of unavailability can cost them millions of dollars in lost revenue. Unfortunately, it is difficult to build highly available storage services that provide useful correctness properties. Both benign (system crashes, power out- ages etc.) and Byzantine faults (memory or disk corruption, software or configuration errors etc.) plague the availability of these services. Furthermore, the goal of high availability conflicts with our desire to provide good performance and strong correctness guarantees. For example, the Consistency, Availability, and Partition- resilience (CAP) theorem states that a storage service that must be available despite network partitions cannot enforce strong consistency. Similarly, the tradeoff between latency and durability dictates that a low-latency service cannot ensure durability in the presence of data-center wide failures. This dissertation explores the theoretical and practical limits of storage services that can be safe and live despite the presence of benign and Byzantine faults. On the practical front, we use cloud storage as a deployment model to build Depot, a highly available storage service that addresses the above challenges. Depot minimizes the trust clients have to put in the third party storage provider. As a result, Depot clients can continue functioning despite benign or Byzantine faults of the cloud servers. Yet, Depot provides stronger availability, durability, and consistency properties than those provided by many of the existing cloud deployments, without incurring prohibitive performance cost. For example, in contrast to Amazon S3’s eventual consistency, Depot provides a variation of causal consistency on each volume, while tolerating Byzantine faults. On the theoretical front, we explore the consistency-availability tradeoffs. Tradeoffs between consistency and availability have proved useful for designers in deciding how much to strengthen consistency if high availability is desired or how much to compromise availability if strong consistency is essential. We explore the limits of such tradeoffs by attempting to answer the question: What are the semantics that can be implemented without compromising availability? In this work, we investigate this question for both fail-stop and Byzantine failure models. An immediate benefit of answering this question is that we can compare and contrast the consistency provided by Depot with that achievable by an optimal implementation. More crucially, this result complements the CAP theorem. While, the CAP theorem defines a set of properties that cannot be achieved, this work identifies the limits of properties that can be achieved. / text
8

Simulation and evaluation of an articulated forklift truck / Simulering och utvärdering av en midjestyrd kombitruck

Johansson, Emil January 2014 (has links)
Today’s demand on forklift trucks performance and efficiency is high. The productivity is important but also the experience while handling the forklift. The handling has to be simple and genuine to make the driver feel confident and safe. To achieve high performance steering in articulated trucks, a hydraulic power system is often used.Simulation software are a powerful tool in development processes. The program gives the industry a possibility to develop, analyze and evaluate constructions and models more efficient.The purpose of this master thesis is to identify and increase the knowledge about the main challenges in the hydraulic steering system in an articulated forklift. The hydraulic system has been modelled in the simulation software Hopsan and validated against data from measurements performed on the forklift. The different challenges have been identified based on tests and the simulation results. For a deeper understanding of the system a literature study, mainly about the key components, has been done during the master thesis. A number of suggestions for improvement have been developed with focus on increasing the steering performance. The concepts and ideas have been evaluated and tested in the simulation model.The project resulted in a validated simulation model of the articulation and a number of suggested improvements on the hydraulic steering system.
9

Replication Fork Stability in Mammalian Cells

Elvers, Ingegerd January 2011 (has links)
Maintaining replication fork integrity is vital to preserve genomic stability and avoid cancer. Physical DNA damage and altered nucleotide or protein pools represent replication obstacles, generating replicative stress. Numerous cellular responses have evolved to ensure faithful DNA replication despite such challenges. Understanding those responses is essential to understand and prevent or treat replication-associated diseases, such as cancer. Re-priming is a mechanism to allow resumption of DNA synthesis past a fork-stalling lesion. This was recently suggested in yeast and explains the formation of gaps during DNA replication on damaged DNA. Using a combination of assays, we indicate the existence of re-priming also in human cells following UV irradiation. The gap left behind a re-primed fork must be stabilised to avoid replication-associated collapse. Our results show that the checkpoint signalling protein CHK1 is dispensable for stabilisation of replication forks after UV irradiation, despite its role in replication fork progression on UV-damaged DNA. It is not known what proteins are necessary for collapse of an unsealed gap or a stalled fork. We exclude one, previously suggested, endonuclease from this mechanism in UV-irradiated human fibroblasts. We also show that focus formation of repair protein RAD51 is not necessarily associated with cellular sensitivity to agents inducing replicative stress, in rad51d CHO mutant cells. Multiple factors are required for replication fork stability, also under unperturbed conditions. We identify the histone methyltransferase SET8 as an important player in the maintenance of replication fork stability. SET8 is required for replication fork progression, and depletion of SET8 led to the formation of replication-associated DNA damage. In summary, our results increase the knowledge about mechanisms and signalling at replication forks in unperturbed cells and after induction of replicative stress. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 2: Submitted. Paper 3: Manuscript. Paper 5: Submitted.
10

A Habitat Evaluation and Management Plan for a Riparian Ecosystem

Wilkinson, Robert N. 05 1900 (has links)
Ecological research involving habitat studies was conducted on the Elm Fork of the Trinity River in Denton County, Texas, from spring 1985 to spring 1986. Habitat Evaluation Procedures and Habitat Suitability Index Models developed by the United States Fish and Wildlife Service were applied to a 1419 hectares study area to determine the quality of habitat for four species: beaver, Castor canadensis, wood duck, Aix sponsa, pileated woodpecker, Dryocopus pileatus, and white crappie, Poxomis annularis. Population estimates were generated. A wildlife management plan was developed for the study area. Habitat Suitability Index Models were found to be overly conservative, underestimating the quality of habitat in areas of ecological transition.

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