Measures of tuna abundance from purse-seine operations in the Eastern Pacific Ocean, adjusted for fleet-wide evolution of increased fishing power, 1960-1971

ENGLISH: The fishing power of the tuna purse-seine fleet of the eastern Pacific Ocean has increased since the early 1960's. Because the entire fleet seems to have adopted equipment and techniques to increase its efficiency in capturing tunas, traditional methods of adjusting catch rates to a reference vessel type of fixed efficiency to index tuna abundance from fishing success are inapplicable. Instead, a methodology for such adjustment based on a mathematical representation of purse seining activities is developed. Observed changes in efficiency in subprocesses of purse seining are then used to adjust catch rates when computing abundance histories for yellowfin and skipjack in large regions of the eastern Pacific Ocean. SPANISH: La eficacia de pesca de la flota de cerco atunera en el Océano Pacífico oriental ha aumentado desde el comienzo del decenio de 1960. Como toda la flota parece haber adoptado equipo y métodos para incrementar su eficaciaen capturar atunes, no se pueden aplicar los métodos tradicionales de ajustar los índices de captura a un tipo normalizado de barco (es decir de eficacia fija) para indicar la abundancia del atún según los resultados de pesca. En su lugar se ha desarrollado un método para realizar tal ajuste basado en una representación matemática de las actividades de las embarcaciones de cerco. Cuando se calcula la abundancia histórica del atún aleta amarilla y barrilete en grandes regiones del Océano Pacífico oriental, se usan entonces los cambios observados en la eficacia de los subprocesos cerqueros para ajustar los índices de captura. (PDF contains 120 pages.

Fixed-wing Aircraft Combat Survivability Analysis for Operation Enduring Freedom and Operation Iraqi Freedom

The primary tenet of the aircraft survivability discipline is threat definition. In order to deliver relevant capabilities and protection to the warfighter it is imperative; therefore, to provide timely, accurate, and actionable threat data to the survivability community. In an attempt to identify the evolution of aircraft threats in today\u27s combat environment, an analysis of fixed-wing aircraft battle damage was conducted. This analysis reports battle damage incidents from OPERATIONS ENDURING FREEDOM (OEF) and IRAQI FREEDOM(OIF). Additionally, reported damage incidents were then validated by crosschecking aircraft maintenance records from this period to eliminate non-hostile fire data points. This revolutionary approach uncovered discontinuities, which were further explored to identify their root cause. As a result, significant Air Force policy changes in the realm of battle damage reporting procedures were suggested. In the end, lives will be saved because the acquisition community at large will have valuable threat data in which they can be confident

NON-FOULING AFFINITY PLATFORMS FOR PROTEIN IMMOBILIZATION IN ELECTRON MICROSCOPY

Single-particle reconstruction has grown significantly with the improvements in various data collection and computational strategies including CTF fitting, the use of vitrified samples and the utilization of ultra-sensitive direct electron detectors. Although these improvements have contributed significantly to the recent evolution of 3D reconstruction analysis, the way samples are prepared for electron microscopy has remained largely unchanged. We report the development of TEM grids that are modified with non-fouling coatings bearing surface grafted nitrilotriacetic acid substituents that promotes specific capture of protein targets for high resolution TEM analysis. The utilization of these grids for specific adsorption of the targeted protein onto the grid surface results in well-controlled surface concentration enhancements and a days-to-minutes reduction in time required for the preparation of a purified sample for cryoEM analysis from an E. coli expression system. The selective and reversible capture of his-tag T7 bacteriophage, RplL, and GroEL from crude lysates, as well as purified nanodisc-solubilized his-malFGK2, on these NTA-modified grids with an exceptionally low level of adsorption by non-target proteins has been observed. Our data illustrates the utility of these grids for selective capture from complex mixtures, detergent-solubilized membrane protein isolates, and expression systems yielding low copy numbers of the desired target in a manner that is well-suited for single particle reconstruction analysis

An Effort Toward Collaborative Problem Solving in Teacher Candidates’ Practicum: Reflection in Action

This qualitative study explores my role as the clinical educator of a university practicum field experience at a public elementary and middle school. Nine teacher candidates participated in this action research that focused on changes implemented over the course of a semester to improve collaborative problem-solving inquiry and discussion. The primary data sources include audio-taped transcripts of purposely selected seminars, pre and post observation conferences, online student discussion board posts on the Learning Management System (LMS) and researcher’s field notes. Findings reveal that, through integration of multiple sources of student input, a clinical educator may develop a more complete feedback loop to facilitate development of student pedagogical perspectives and integration into the host school culture. Overall, there was a greater level of collaboration among teacher candidates and myself, as a co-participant and collaborator in their emerging practice

Exploring the cybercrime capacity and capability of local law enforcement agencies in the United States

2021 Fall.Includes bibliographical references.The relentless pace of technological innovation has changed how people communicate, interact, and conduct business, creating new pathways and opportunities for people to commit crimes or engage in harmful behavior via the internet or digitally networked devices. Cybercrime is rapidly scaling up, leading many to predict that it will become the next significant global crisis (Krebs, 2021; Viswanathan & Volz, 2021; Zakaria, 2021). In the United States, local law enforcement agencies and their personnel stand at the frontlines of the cybercrime problem (Police Executive Research Forum, 2014). This dissertation project was inspired by several calls to action to explore and evaluate how law enforcement agencies are responding to the cybercrime problem (Holt & Bossler, 2014; Ngo & Jaishankar, 2017). The research conducted in this project aligns with and extends a small body of exploratory and evaluative research focusing on local law enforcement agencies and cybercrime (for example Harkin et al., 2018; Monaghan, 2020; Nowacki & Willits, 2016). By utilizing a mixed methods research design consisting of a survey and series of qualitative interviews this project helped address the research question: What is the current cybercrime capacity and capability of local law enforcement agencies in the United States? Findings from this project advance our knowledge about the cybercrime capacity and capability of local law enforcement agencies and contribute to strengthening law enforcement practice, policy, and future research. In total, 925 county and municipal agencies participated in this research project through a survey instrument called the Cybercrime Capacity and Capability Questionnaire (CCCQ©), with 855 agencies providing data usable for analysis. Additionally, 23 individuals representing 23 distinct agencies, who previously participated in the CCCQ, also participated in a series of semi-structured qualitative interviews. Multiple findings and recommendations were derived as a result of the participation by these agencies and individuals in this project. Several findings from this project aligned with or validated findings and recommendations from other recent studies (for example Harkin et al., 2018). Among the key findings from this project are that the cybercrime capacity and capability of local law enforcement agencies is deficient, despite trends at the local law enforcement agency level to allocate more resources to the cybercrime problem. This deficiency is noted both by response patterns on the CCCQ© and through comments supplied during the qualitative interviews. Lack of financial and personnel resources, especially technologically skilled and competent personnel, limited and/or outdated technological infrastructure, and problems leveraging partnerships and obtaining cooperation from private sector organizations are just a few of the challenges hampering the development of a more robust local law enforcement cybercrime capacity and capability. Results and insights from this research also illuminate the dynamic process of developing cybercrime capacity and capability. Result from this project indicate that caution should be exercised before assuming that cybercrime capacity and capability are solely a function of agency size. While this project substantiates other research that shows larger agencies are more likely to have cybercrime units, and also tend to have more resources, personnel, and equipment for cybercrime investigations, they do not necessarily have greater cybercrime capacity or capability. Cybercrime case volume appears to impact cybercrime capacity and capability such that large local law enforcement agencies, despite specialized cybercrime units and more resources allocated to cybercrime, may not be better off in managing cybercrime incidents or responding to cybercrime related issues than midsize and smaller local agencies. Personnel at larger agencies, despite having dedicated cybercrime units, more resources, and better equipment, may be at higher risk of burnout and other issues as a result. In short, extremely high cybercrime case volumes may undermine the capacity and capability of even the most robustly developed specialized cybercrime units, as well as the best equipped and resourced agencies. Given the pace at which the cybercrime problem is growing, this is a troubling finding. This project also highlights that cybercrime capacity and capability cannot be understood without accounting for the critical differences that external forces and contextual factors produce on local law enforcement agencies that, in turn, impact how those agencies function and adapt to new issues and challenges. For example, qualitative data from this project help us to understand the connections between the defund the police movement and the COVID-19 pandemic, both of which appear to be undermining the capacity and capability of local law enforcement agencies, and thus negatively impacting their cybercrime capacity and capability. As a result, cybercrime administrators and personnel at local law enforcement agencies in the U.S. may be experiencing similar challenges to their peers abroad (see Harkin et al. 2018). A number of directions for future research, improvement of the CCCQ©, and recommendations for improving police practice and policy such as developing uniform, and operationalizable cybercrime best practices and strengthening private sector compliance with law enforcement agency requests for data are also provided

RACIAL AND ETHNIC DIFFERENCES IN ACCESSING TIMELY CANCER SCREENING AND TREATMENT SERVICES: A QUANTITATIVE ANALYSIS

This research is organized into three integrated studies that explored differences in screening and treatment services across the cancer care continuum by race and ethnicity. The Andersen Behavioral Model of Health Services Use and the Five Dimensions of Access were used as conceptual frameworks. In the first study (Chapter 2), data from the Medical Expenditure Panel Survey were used to examine breast and cervical cancer screening rates before and during the Great Recession (2007-2009). The interaction terms of recession and race and ethnicity were controlled to examine whether minorities exhibited different utilization patterns under economic shock compared to Whites. In Chapter 3, data from the National Health Interview Survey (NHIS) from 2006-2010 were used to identify adult cancer survivors and adults without a history of cancer. Multivariate logistic regressions were applied to examine the prevalence of cost, organizational and transportation barriers between survivors and the general population. The likelihood of experiencing barriers was explored by race and ethnicity. In Chapter 4, differences in the likelihood of experiencing access barriers among survivors by race and ethnicity was explored. Data were merged from the 2000-2011 (NHIS) to identify adult cancer survivors who reported cost, organizational and transportation barriers. Logistic regressions were applied to determine the likelihood of reporting each type of barrier, while controlling for demographic and socioeconomic variables. The Fairlie decomposition technique was applied to identify contributing factors that explained differences in accessing care based by race and ethnicity. Overall, results of the investigations demonstrate that: (1) breast and cervical screening rates declined most among White women during the recession period, while rates increased among Hispanic women during the same period; (2) minority cancer survivors were significantly more likely to experience access-to-care barriers than Whites; and (3) insurance, comorbidity, perceived health and nativity were leading factors that contributed to racial and ethnic differences in timely receipt of cancer screening and treatment services. As provisions of the Affordable Care Act take effect, findings provide insight into practices, policies, and future research that will help achieve Healthy People 2020 screening objectives and reduce racial and ethnic disparities in accessing timely cancer care

Survival of Salmonella Strains in Ground Beef Containing Varying Fat Contents and Heated at Varying Calculated Lethalities

Americans consume 28 lbs of ground beef annually. Beef can become contaminated with Salmonella during the initial slaughter process. Whole cuts of meat are ground into other products and the contamination spreads. This increases the risk of food borne illness for many Americans that consume ground beef products. The purpose of this study is to determine if adequate microbial destruction of Salmonella populations in ground beef of different fat levels can be achieved at temperatures that are lower than government guidelines. Ground beef was inoculated with a four-strain mixture of Salmonella. Three fat levels of ground beef were used (10, 17, and 25% fat). Samples of ground beef (10g) were heated in a water bath to target temperatures of 60, 65.5, and 71.1°C. The heated samples were removed from the water bath at predetermined time intervals and cooled in an ice bath. Salmonella was enumerated on plate count agar (PCA). Serotype survival was also analyzed. The heat treatments significantly decreased bacteria populations (p \u3c 0.05) and the 60, 65.6, and 71.1 °C heat treatments were significantly different from each other. The results indicate that fat level had no significant effect on bacterial survival (p \u3e 0.05). Also, S. Senftenburg was found most often during longer exposure to heat treatment. Overall, the results indicate that combinations of heating at 60, 65.6 °C can achieve similar bacterial destruction as heating at 71.1 °C and should be considered by manufactures that use ground beef

BPS states of D=4 N=1 supersymmetry

We find the combinations of momentum and domain-wall charges corresponding to BPS states preserving 1/4, 1/2 or 3/4 of D=4 N=1 supersymmetry, and we show how the supersymmetry algebra implies their stability. These states form the boundary of the convex cone associated with the Jordan algebra of $4\times 4$ real symmetric matrices, and we explore some implications of the associated geometry. For the Wess-Zumino model we derive the conditions for preservation of 1/4 supersymmetry when one of two parallel domain-walls is rotated and in addition show that this model does not admit any classical configurations with 3/4 supersymmetry. Our analysis also provides information about BPS states of N=1 D=4 anti-de Sitter supersymmetry.Comment: Latex, 27 pages. Various corrections and improvements including an expanded discussion on BPS states in ad

Neurocognitive Mechanisms of Statistical-Sequential Learning: what do Event-Related Potentials Tell Us?

Statistical-sequential learning (SL) is the ability to process patterns of environmental stimuli, such as spoken language, music, or one’s motor actions, that unfold in time. The underlying neurocognitive mechanisms of SL and the associated cognitive representations are still not well understood as reflected by the heterogeneity of the reviewed cognitive models. The purpose of this review is: (1) to provide a general overview of the primary models and theories of SL, (2) to describe the empirical research – with a focus on the event- related potential (ERP) literature – in support of these models while also highlighting the current limitations of this research, and (3) to present a set of new lines of ERP research to overcome these limitations. The review is articulated around three descriptive dimensions in relation to SL: the level of abstractness of the representations learned through SL, the effect of the level of attention and consciousness on SL, and the developmental trajectory of SL across the life-span. We conclude with a new tentative model that takes into account these three dimensions and also point to several promising new lines of SL research