A study of applicants for the Master of Education degree at the School of Education, Boston University, from 1947 to 1957

Thesis (Ed.M.)--Boston Universit

Role transition and the nurse practitioner: an investigation into the experience of professional autonomy.

This research project explores nurse practitioners' experiences of role transition and professional autonomy, aiming to gain a new understanding of how nurse practitioners experience their role, and seeking new insight into the potential of the nurse practitioner role in the ever changing arena of health care delivery. The study addresses the concept of professional autonomy, and the boundaries of professional practice, and links this to the legal, ethical and epistemological foundations of nursing practice in general, and more specifically to the professional role of the nurse practitioner. Amongst specialist nursing roles, the position of the nurse practitioner is of particular interest, because nurse practitioners have evolved within an interprofessional philosophy of care, and therefore have complex issues relating to the scope of their professional practice, their individual and professional identity, and their professional autonomy. The research was conducted using a phenomenological hermeneutic approach inspired by Ricoeur (1976, 1981), and placed a significant emphasis on the meaning of the lived experience of the participant nurse practitioners within their professional role. Narrative interviews with fourteen nurse practitioners were transcribed to create a series of texts for subsequent analysis. Data analysis provided a progressive exploration of the meaning of the experience of professional autonomy for the participants in the study, and incorporated a descriptive analysis and an interpretive account of the phenomenon. From this hermeneutic analysis a new interpreted sense emerged, and a comprehensive understanding of the meaning of the phenomenon under review could be formulated. The findings reflect a generally positive view of practice on the part of nurse practitioners, but highlight a number of barriers to the development of their professional autonomy. Professional relationships are central to the experience of professional autonomy, and the future development of the nurse practitioner role. The findings reinforce the need for clearer definition of the nurse practitioner role, and suggest that further reflection on the nature of advanced practice, and the relationship between nurse practitioners and the wider profession of nursing might help in this regard

Diagnosing Tropical Cyclone Rapid Intensification Through Rotated Principal Component Analysis of Synoptic-Scale Diagnostic Fields

Forecasts of rapid intensification (RI) within tropical cyclones continue to be a major challenge, primarily due to difficulty in determining the processes that distinguish RI and non-RI storms. In this study, the aim was to identify the most important RI/non-RI discriminatory variables in the North Atlantic basin, not only by level, but also spatial location relative to the tropical cyclone center. These important variables, identified using rotated principal component analysis on one-dimensional and three-dimensional GEFS reforecast base-state variables from 1985 to 2009, led to the identification of diagnostic fields with the largest variability between RI and non-RI events. Hierarchical clustering techniques performed on rotated PC loadings provided map types of RI and non-RI cyclones. Analysis of these composite map types, as well as composite derived fields including divergence, relative vorticity, equivalent potential temperature, static stability, and vertical shear, revealed interesting distinguishing characteristics between RI and non-RI events. Results suggested that vorticity in the mid-levels, divergence in the upper-levels, equivalent potential temperature, and specific humidity play critical roles in successfully discriminating between RI and non-RI storms. These findings give key insights to which variables should be used in developing a prognostic classification scheme to assist with operational forecasts of tropical cyclone RI

Identification of a predicted partner-switching system that affects production of the gene transfer agent RcGTA and stationary phase viability in Rhodobacter capsulatus

Background: Production of the gene transfer agent RcGTA in the α-proteobacterium Rhodobacter capsulatus is dependent upon the response regulator protein CtrA. Loss of this regulator has widespread effects on transcription in R. capsulatus, including the dysregulation of numerous genes encoding other predicted regulators. This includes a set of putative components of a partner-switching signaling pathway with sequence homology to the σ-regulating proteins RsbV, RsbW, and RsbY that have been extensively characterized for their role in stress responses in gram-positive bacteria. These R. capsulatus homologues, RbaV, RbaW, and RbaY, have been investigated for their possible role in controlling RcGTA gene expression. Results: A mutant strain lacking rbaW showed a significant increase in RcGTA gene expression and production. Mutation of rbaV or rbaY led to a decrease in RcGTA gene expression and production, and these mutants also showed decreased viability in the stationary phase and produced unusual colony morphologies. In vitro and in vivo protein interaction assays demonstrated that RbaW and RbaV interact. A combination of gene disruptions and protein-protein interaction assays were unsuccessful in attempts to identify a cognate σ factor, and the genetic data support a model where the RbaV protein that is the determinant regulator of RcGTA gene expression in this system. Conclusions: These findings provide new information about RcGTA regulation by a putative partner-switching system and further illustrate the integration of RcGTA production into R. capsulatus physiology

Calculating individual lifetime effective risk from initial mean glandular dose arising from the first screening mammogram

Objectives: To use the initial mean glandular dose (MGD) arising from the first screening mammogram to estimate the individual total screening lifetime effective risk. Methods: Organ doses from FFDM screening exposures (craniocaudal and mediolateral oblique for each breast) were measured using a simulated approach, with average breast thickness and adult ATOM phantoms, on 16 FFDM machines. Doses were measured using TLDs accommodated inside the ATOM phantom; examined breast MGD was calculated. Total effective risk during a client’s lifetime was calculated for 150 screening scenarios of different screening commencement ages and frequencies. For each scenario, a set of conversion factors were obtained to convert MGD values into total effective risk. Results: For the 16 FFDM machines, MGD contributes approximately 98% of total effective risk. This contribution is approximately constant for different screening regimes of different screening commencement ages. MGD contribution remains constant but the risk reduced because the radio-sensitivity of all body tissues, including breast tissue, reduces with age. Three sets of conversion factors were obtained for three screening frequencies (annual, biennial, triennial). Three relationship graphs between screening commencement age and total effective risk, as percentages of MGD, were created. Conclusions: Graphical representation of total risk could be an easy way to illustrate the total effective risk during a client’s lifetime. Screening frequency, commencement age, and MGD are good predictors for total effective risk generating more understandable data by clients than MGD

Investigating the relationship between HIV testing and risk behaviour in Britain: National Survey of Sexual Attitudes and Lifestyles 2000.

OBJECTIVES: To estimate the prevalence of, and identify factors associated with, HIV testing in Britain. DESIGN: A large, stratified probability sample survey of sexual attitudes and lifestyles. METHODS: A total of 12,110 16-44 year olds completed a computer-assisted face-to-face interview and self-interview. Self-reports of HIV testing, i.e. the timing, reasons for and location of testing, were included. RESULTS: A total of 32.4% of men and 31.7% of women reported ever having had an HIV test, the majority of whom were tested through blood donation. When screening for blood donation and pregnancy were excluded, 9.0% of men and 4.6% of women had had a voluntary confidential HIV test (VCT) in the past 5 years. However, one third of injecting drug users and men who have sex with men had a VCT in the past 5 years. VCT in the past 5 years was significantly associated with age, residence, ethnicity, self-perceived HIV risk, reporting greater numbers of sexual partners, new sexual partners from abroad, previous sexually transmitted infection diagnosis, and injecting non-prescribed drugs for men and women, and same-sex partners (men only). Whereas sexually transmitted disease clinics were important sites for VCT, general practice accounted for almost a quarter of VCT. CONCLUSION: HIV testing is relatively common in Britain; however, it remains largely associated with population-based blood donation and antenatal screening programmes. In contrast, VCT remains highly associated with high-risk (sexual or drug-injecting) behaviours or population sub-groups at high risk. Strategies to reduce undiagnosed prevalent HIV infection will require further normalization and wider uptake of HIV testing

Designing for video: investigating the contextual cues within viewing situations

The viewing of video increasingly occurs in a wide range of public and private environments via a range of static and mobile devices. The proliferation of content on demand and the diversity of the viewing situations means that delivery systems can play a key role in introducing audiences to contextually relevant content of interest whilst maximising the viewing experience for individual viewers. However for video delivery systems to do this they need to take into account the diversity of the situations where video is consumed, and the differing viewing experiences that users desire to create within them. This requires an ability to identify different contextual viewing situations as perceived by users. This paper presents the results from a detailed, multi-method, user centred field study with 11 UK based users of video-based content. Following a review of the literature (to identify viewing situations of interest on which to focus), data collection was conducted comprising observation, diaries, interviews and self-captured video. Insights were gained into whether and how users choose to engage with content in different public and private spaces. The results identified and validated a set of contextual cues that characterise distinctive viewing situations. Four archetypical viewing situations were identified: ‘quality time’, ‘opportunistic planning’, ‘sharing space but not content’ and ‘opportunistic self- indulgence’. These can be differentiated in terms of key contextual factors: solitary/shared experiences, public/private spaces, and temporal characteristics. The presence of clear contextual cues provides the opportunity for video delivery systems to better tailor content and format to the viewing situation or additionally augment video services through social media in order to provide specific experiences sensitive to both temporal and physical contexts

Discrimination of Tornadic and Non-Tornadic Severe Weather Outbreaks

Outbreaks of severe weather affect the majority of the conterminous United States. An outbreak is characterized by multiple severe weather occurrences within a single synoptic system. Outbreaks can be categorized by whether or not they produce tornadoes. It is hypothesized that the antecedent synoptic signal contains important information about outbreak type. Accordingly, the scope of this research is to determine the extent that the synoptic signal can be utilized to classify outbreak type at various lead times.Outbreak types are classified using the NCEP/NCAR reanalysis data, which are arranged on a global 2.5º latitude-longitude grid, include 17 vertical pressure levels, and span from 1948 to the present (2008). Fifty major tornado outbreak (TO) cases and fifty major non-tornadic severe weather outbreak (NTO) cases are selected for this work. Two types of analyses are performed on these cases to assess discrimination ability. One analysis involves outbreak classification using the Weather Research and Forecasting (WRF) model initialized with the NCEP/NCAR reanalysis dataset. Meteorological covariates are computed from the WRF output and used in training and testing of statistical classification models. The covariate fields are depicted on a 21 X 21 gridpoint field with an 18 km grid spacing centered on the outbreak. Covariates with large discrimination potential are determined using permutation testing. A P-mode principal component analysis (PCA) is used on the subset of covariates determined by permutation testing to reduce data dimensionality, since numerous redundancies exist in the initial covariate set. Three statistical classification models are trained and tested with the resulting PC scores: a support vector machine (SVM), a logistic regression model (LogR), and a multiple linear regression model (LR). Promising results emerge from these methods, as a probability of detection (POD) of 0.89 and a false alarm ratio (FAR) of 0.13 are obtained from the best discriminating statistical technique (SVM) at 24-hours lead time. Results degrade only slightly by 72-hours lead time (maximum POD of 0.833 and minimum FAR of 0.276).Synoptic composites of the outbreak types are the second analysis considered. Composites are used to reveal synoptic features of outbreak types, which can be utilized to diagnose the differences between classes (in this case, TOs and NTOs). The composites are created using PCA. Five raw variables, height, temperature, relative humidity, and u and v wind components, are extracted from the NCEP/NCAR reanalysis data for North America. Converging longitude lines with increasing latitude on the reanalysis grid introduce bias into correlation calculations in higher latitudes; hence, the data are mapped onto both a latitudinal density grid and a Fibonacci grid. The resulting PCA produces two significant principal components (PCs), and a cluster analysis on these PCs for each outbreak type results in two types of TOs and NTOs. TO composites are characterized by a trough of low pressure over the central United States and major quasigeostrophic forcing features such as an upper level jet streak, cyclonic vorticity advection increasing with height, and warm air advection. These dynamics result in a strong surface cyclone in most tornado outbreaks. These features are considerably less pronounced in NTOs. The statistical analyses presented herein were successful in classifying outbreak types at various lead times, using synoptic scale data as input