496 research outputs found
A proportional counter spectrometer study of the beta-decay of radioactive S-35, Pm-147, Ni-63, and C-14
A proportional counter spectrometer, hereinafter denoted as a p.c.s., of unique design has been constructed for the purpose of measuring beta-spectra whose energies lie below a few hundred Kev. The p.c.s. is well suited for the problem in that thin and uniform radioactive sources which are essential for accurate low energy spectral measurements can be employed. The utilization of radioactive sources of low surface densities is made possible by an allowable source area of a few square centimeters and an ~100 per cent geometrical efficiency for particle detection by the p.c.s. In addition, the p.c.s. obviates a Geiger-Huller counter window of finite thickness which is often associated with the magnetic spectrometers. The penetration of beta-particles through the Geiger-Muller counter window can lead to distortion of the beta-spectrum at low energies
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Unraveling the Influence of Heritable Genetic Variation on Nicotine Use and Complex Human Traits
Smoking, a leading cause of preventable deaths worldwide and with both genetic and environmental influences, has been associated with numerous health risks, prompting the need for a deeper understanding of its genetic liability. Developing a deeper comprehension of the genetic factors influencing smoking behaviors may enhance our understanding of molecular pathways, networks, and their associations with other traits, aiming to identify potential treatment targets. Furthermore, the multifaceted nature and diverse genetic and environmental influences of smoking traits makes them exemplary phenotypes for understanding the genetics of complex traits. This dissertation encompasses three novel studies aimed at investigating the genetic influences on nicotine use and other complex traits. Chapter 2 used genome-wide association study summary statistics to examine whether human orthologs of genes identified in mice exposed to nicotine during development influence smoking behaviors in humans. This approach provided insight into the potential shared genetic architecture across species. Chapter 3 explored the use of expression-based gene-single nucleotide polymorphism (SNP) annotations to enhance the identification of relevant tissues associated with complex traits, including smoking behaviors. By leveraging estimated expression effects, this study aimed to uncover tissue-specific mechanisms underlying these traits. In Chapter 4, a transcriptome-wide association study was conducted to identify and characterize relevant SNPs, genes, and tissues associated with nicotine use and other complex traits. This study included diverse cohorts of varying ancestries and proposed methods to leverage multiple unrelated samples for enhanced statistical power. Collectively, the presented findings emphasize the polygenic nature of complex traits, highlight the need for larger and more ancestrally diverse sample sizes, and expand our toolkit for investigating genetic architecture, offering new avenues for exploring the genetics of human complex traits.</p
Piloting of the Concerns-based Adoption Model: Farmer Concerns About the Participatory Guarantee System in Cambodia
While there is a large body of adoption and agricultural extension literature on the process of introducing a new technology, agricultural development projects are often expected to produce immediate results that do not always allow for the integration of these theories into practice. The Concerns-based Adoption Model (CBAM) is a framework that places participants at the center of the change process to identify their concerns and challenges, providing a roadmap for projects to guide individuals with the correct support for their particular stage of adoption. CBAM has typically been used for the introduction of new curriculum in formal education. But this study assessed the potential for CBAM to be applied to agriculture innovations. In this study, we adapted and piloted the CBAM “Stages of Concern” model to assess adoption of an agriculture innovation. The innovation is the Participatory Guarantee System (PGS) for Cambodian vegetable farmers. We assessed the potential for CBAM as a tool for agricultural development project management. We found that the adapted survey consistently placed farmers in the anticipated Stage of Concern. Identifying users’ Stages of Concern can inform program designers and practitioners, assisting in tailoring support across the adoption process. CBAM has the potential to inform participatory project design and give project administrators an evidence-based, systematic protocol for assessing the adoption process, adding another tool to the development practitioners’ toolbox
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A project management focused framework for assuring quality work processes
Federal Manufacturing & Technologies/New Mexico (FM&T/NM) of AlliedSignal is an organization of approximately 300 associates providing operations support, engineering, and other technical services for DOE, New Mexico`s National Laboratories, etc. Work performed is primarily project-oriented and ranges from executing a major long-term contract for retrofitting and maintaining a large fleet of escort vehicles to creating a single, small, prototype electronic device for measuring radiation in a unique environment. FM&T/NM is functionally organized and operates in a classic matrix format with functional departments providing personnel with technical expertise, necessary physical resources, and administrative support to several project-based groups. Like most matrix-based organizations that provide support to diverse customers, FM&T/NM has encountered problems that occur when a group of project managers is expected to work together in using and scheduling a shared set of limited resources for the good of the organization as a whole. The framework for managing projects that we present focuses on developing, understanding, and managing the relationships between the functional organization structure, the system of work processes, and the management of projects. FM&T/NM retains its functional structure which primarily assigns personnel to work processes. The evolving role of the process leader focuses primarily on designing, managing, and improving the process, and the interactions among the subprocesses. The project manager is responsible for (1) translating customer requirements into product specifications, (2) determining the sequence of activities needed to meet project goals, (3) scheduling the required work processes, (4) monitoring project progress, (5) providing liaison between the customer and process leaders, and (6) having the desired product and/or service delivered to a satisfied customer in a timely manner
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