Long-Term and Seasonal Drivers of Phytoplankton Assembly in a Subtropical Monomictic Lake

Seasonal phytoplankton dynamics in lakes are highly sensitive physicochemical changes in the water column. As climate-driven frequency and variability of precipitation increases, lakes may experience increased inputs of allochthonous organic matter and nutrients through pulsed rain events. The resultant effects of lake physicochemistry on phytoplankton seasonal succession and assemblage are poorly understood. In the current study, the phytoplankton assemblage of a subtropical monomictic lake was examined in the context of natural interannual oscillations in allochthonous dissolved organic carbon and nutrient inputs resulting in prolonged clear-water and dark-water phases over a 14-year period. Differences in water clarity and nutrient concentrations among phases caused pronounced assemblage and morphology-based functional grouping shifts largely associated with hydrologic effects of the Pacific Decadal Oscillation. Determining how phytoplankton assemblages respond to changes in allochthonous supplies is critical to understanding and predicting the cascading effects of climate on lake ecosystems at all latitudes

Shedding light on living cells and mineralised tissues using Raman spectroscopy

Raman micro-spectroscopy presents a highly sensitive, non-invasive, and rapid way to collect biochemical information from cells and tissues. The resulting Raman spectrum is a chemical ‘fingerprint’ containing a wealth of molecular level information which has been used to characterize, monitor, compare and confirm biological processes from the cellular to tissue levels. The work presented in this thesis utilizes Raman spectroscopy to test live in vitro cellular models, classify human tissues of interest, and determine the biomolecular differences in tissue samples which are diseased or undergoing therapeutic treatment. Additionally new ways of visualizing and interpreting multivariate analytical results are proposed and demonstrated to ease the determination of the biomolecular features which are most important when comparing sample groups. A persistent challenge in the interpretation of information rich biological Raman spectra includes the multitude of signals from lipids, proteins, carbohydrates, nucleic acids, and minerals found in a limited spectral range and in some instances overlapping significantly. Partial Least Squares – Discriminant Analysis (PLS-DA) Variable Importance Projection (VIP) scores were presented as heat maps overlaying difference spectra to ease the visualization of significant biochemical bond changes between sample groups and their trends. The advantages of applying PLS-DA VIP scores in this way are demonstrated in well studied and known system including a cultured cellular model incorporating fixation methods and a human tissue comparison between healthy and osteoporotic bone. PLS-DA VIP score plots were additionally utilized to characterize and compare the biolomecular environments surrounding the recently described microscopic mineral inclusions in human aortic valves and aortae. The PLS-DA VIP score plots exposed the chemical differences in these systems through highlighting the corresponding spectral bands in an easy to read and interpret way. Raman micro-spectroscopy was also applied to investigate an in vitro ‘calcified’ porcine aortic valvular interstitial cell model. This model system was probed for the first time using the combination of Raman micro-spectroscopy and complimentary gold standard biological techniques to determine the protein and potential mineral content within these nodular, cellular systems. The ‘calcified’ porcine aortic valvular cell nodules showed no evidence of mineral inclusion. These nodules did exhibit a heavy extracellular matrix production including the production of collagen I. The porcine aortic valvular cell nodules acting as a model system for diseased aortic valve tissue requires not only the characterization of the cell nodule in vitro but also the characterization of the human disease spectrum which the model is suggested to replicate. The discovery and characterisation of microscopic mineral spherical inclusions (50nm-200µm) located in both valvular and vascular tissues leads to an interesting question on the introduction and role of microscopic mineral deposits in cardiovascular disease. Here Raman micro-spectroscopy was utilized to investigate the organic matrix surrounding these microscopic mineral deposits to determine if any colocalised protein changes exist. Protein and specifically collagen changes are demonstrated between tissues with and without the spherical mineral deposits despite being macroscopically indistinguishable. Raman spectroscopy was also utilized to provide direct insights into tissue constituent and structural changes on the molecular level in heat-induced tissue fusion via radio-frequency (RF) energy. This type of tissue fusion has gained wide acceptance clinically and is presented here as the first optical-Raman-spectroscopy study on tissue fusion samples in vitro. This study exposed spectroscopic evidence for the loss of distinct collagen fibres rich tissue layers as well as the denaturing and restructuring of collagen crosslinks post RF fusion. Raman spectroscopy is a demonstrated, powerful, biomolecular imaging technique which benefits from advancements in mathematical analytical techniques as well as its own application in biological investigations. This thesis explores the application of Raman spectroscopy in combination with powerful analytical techniques to further characterize and compare biological systems of interest.Open Acces

Understanding children\u27s exposure to domestic violence: A review of the literature; and, situational-contextual factors that mediate the impact of exposure of domestic violence on children: A retrospective study of adult women residing in Perth

Based on the available theoretical and empirical research literature, this review examines the complexity of children\u27s exposure to domestic violence. In addition to identifying numerous theories which have been used in the literature to help understand how exposure to domestic violence may affect children\u27s adjustment and functioning, this review provides an in depth overview of the research investigating the short and long-term impact of domestic violence exposure on children and young people. Despite the consistent finding across studies that children\u27s witnessing of domestic violence is associated with a host of psychological, social and behavioural problems, there is also evidence in the literature to suggest that the majority of children who witness domestic violence do not demonstrate any adverse consequences. Contextual factors which may explain the variability in children\u27s responses to domestic violence have been identified and summarised, together with protective factors which may contribute to children\u27s resiliency following domestic violence exposure. Definitional and methodological limitations of the literature are discussed, together with suggestions for future research in this area. Much of the existing research on children and domestic violence has focused on the negative consequences of witnessing such violence. However, in recent years several researchers have endeavoured to identify factors that promote resilience among children who are exposed to domestic violence. Due to the paucity of qualitative research studies examining children\u27s experiences of domestic violence exposure as well as the factors that mediate the impact of witnessing such violence, this study aimed to address these gaps in the research. Specifically, this study aimed to explore women\u27s experiences of witnessing domestic violence during their childhood and adolescent years as well as the factors that influenced their ability to cope with witnessing such violence. Six women who had witnessed domestic violence during childhood or adolescence were interviewed using a qualitative research design with a phenomenological and resilience framework. Six dominant themes, each with a number of subthemes emerged from the data. These were: the context of the violence, the characteristics of the violence, the impact of domestic violence, coping and survival strategies and outcomes. The implications of this study for research in the area of domestic violence are discussed

Virtual Standardized Patient

Background: Higher education nursing programs include a physical/health assessment course that prepares graduates to provide excellent care based on data collected through assessment. Finding a teaching strategy that engages students as well as educates them in health assessment techniques is a challenge that all nurse educators share. Objectives: The objectives of this study were to determine the level of engagement and learning that occurred with undergraduate and graduate students who participated in a health assessment course that included the use of an online virtual standardized patient (VSP). Design: Quantitative, descriptive survey research was utilized to determine student nurses’ perception of the use of VSP in a physical assessment course.  Setting/Participants: Students in a traditional on-campus BSN program and students in an online RN to BSN and MSN program were included in this study. Methods: After receiving IRB approval, course leaders provided students a standardized questionnaire of two (2) multiple choice and six (6) Likert-style questions. The questions evaluated the participants’ ease of use, comparison of interaction between online virtual and live human patients, ability to perform an exam on a virtual patient, and ability to communicate with a virtual patient.  Questionnaires were administered to volunteers in the three identified health assessment courses (BSN, RN-BSN, and MSN).  Also evaluated was the participant’s perception of their ability to transfer knowledge from the VSP to the live patient.  All students participated in the VSP with completion of the questionnaire optional. Results: Findings in this study generally supported the educational value of using a virtual standardized patient in teaching both undergraduate and graduate students’ health assessment. Variations between the groups were found. Conclusion: Use of a virtual standardized patient is a positive teaching strategy for teaching health assessment in both undergraduate and graduate nursing programs

The Zoi Program: a new model for youth ministry

The youth ministry program at the United Church of Christ in Abington, Massachusetts is outdated and stagnant. Although UCC Abington has made many positive changes in recent years to be sure it remains modern and relevant, it has failed to address its antiquated youth program. This project explores the changing church of the twenty-first century, and the place of young people within it. This project will investigate the practical concerns that make it difficult for young people to be involved in the church, and the spiritual concerns that often cause them to turn away from the church. The project will also delve into what youth desire and what this youth leader desires for the faith development and spiritual wellness of youth at UCC Abington. Through the lens of practical theology, this project proposes a new and different format for a youth program in the church that will give young people the opportunity to understand and practice their faith in the context of their lives

Comparison of Computerized Dynamic Posturography (CDP) results with subjective visual vertical (SVV) test in patients with and without vestibular dysfunction: effects of horizontal headshaking

The goal of the study was to identify what effect headshaking in the horizontal plane has on Computerized Dynamic Posturography results in normals and patients with unilateral vestibular dysfunction. Additionally, the results were compared to results of the dynamic subjective visual vertical test

The Haemophilus ducreyi SAP Transporter Contributes to Antimicrobial Peptide Resistance

Indiana University-Purdue University Indianapolis (IUPUI)Haemophilus ducreyi is the causative agent of the genital ulcer disease chancroid, which has been shown to facilitate the transmission of HIV. H. ducreyi is likely exposed to multiple sources of antimicrobial peptides in vivo. APs are small, cationic molecules with both bactericidal and immunomodulatory functions. Because H. ducreyi is able to establish and maintain an infection in an environment rich with antimicrobial peptides, we hypothesized that the bacterium was resistant to the bactericidal effects of these peptides. Using a 96-well AP bactericidal assay, we examined H. ducreyi susceptibility to eight human APs likely to be encountered at the site of infection, including the α-defensins human neutrophil peptide-1, human neutrophil peptide-2, human neutrophil peptide-3, and human defensin 5, the β-defensins human β defensin-2, human beta defensin-3, and human beta defensin-4, and the human cathelicidin, LL-37. H. ducreyi survival was compared to the survival of Escherichia coli ML35, a strain known to be susceptible to several antimicrobial peptides. H. ducreyi was significantly more resistant than E. coli ML35 to the bactericidal effects of all peptides tested. Furthermore, we found that representative class I and class II strains of H. ducreyi were each resistant to APs of each functional category, indicating that resistance to antimicrobial peptides could represent a conserved method of pathogenesis for H. ducreyi as a species. The H. ducreyi genome contains a homolog for the Sap influx transporter. To study the role of the H. ducreyi Sap transporter in AP resistance, we generated an isogenic sapA mutant and used the 96-well AP bactericidal assay to compare the AP susceptibility profiles of wild-type H. ducreyi, the sapA mutant and the sapA trans-complement to α-defensins, β-defensins, and LL-37. We observed a 25% decrease in the survival of the sapA mutant when it was exposed to LL-37. These findings suggest that the H. ducreyi Sap transporter plays a role in H. ducreyi resistance to LL-37, but it is likely that other AP resistance mechanisms co-exist within the bacterium

Understanding data reuse and barriers to reuse of archaeological data: a quality-in-use methodological approach

Over the last decade, innovation has centred on making archaeological data more interoperable, increasing the discoverability of data through integrated cross-search and facilitating knowledge creation by combining data in new ways. An emerging research challenge for the next decade is optimising archaeological data for reuse and defining what constitutes good practice around reuse. Critical to this research is understanding the current state-of-the-art regarding both existing best practices and barriers to using and reusing archaeological data. This research aimed to understand how to optimise archives and interfaces to maximise the discovery, use and reuse of archaeological data and explore how archaeological archives can better respond to user needs. The study was bound by (i) the reuse of digital archaeological archives; (ii) orientation to content usability and reusability; (iii) maintaining a user-orientated approach; (iv) collecting data from professionals in archaeology and heritage. The research group members adopted the quality-in-use conceptual approach for this study. Quality in use is 'the degree to which a product or system can be used by specific users to meet their needs to achieve specific goals with effectiveness, efficiency, satisfaction, and freedom from risk in specific contexts of use'. The research methodology is based on the SQuaRE (System and Software Quality Requirements and Evaluation) model, represented in the ISO/IEC 25000 standards series. In addition, the quality-in-use metric for investigation of reuse and barriers to reuse of archaeological data were adopted from the standardised measurement functions and methods of ISO/IEC 25022:2016. The result was a methodological model composed of 5 characteristics (Effectiveness, Efficiency, Satisfaction, Context coverage and Usability) with 14 measures (Task completeness, Objectives achievement, Task time, Cost-effectiveness, Overall satisfaction, Satisfaction with features, User trust in the system, data and paradata, User pleasure, Physical comfort, Context completeness, Flexible context of use and User guidance completeness). The methodology was tested with specific Contexts of use (use cases), orientated to a distinct user with the specific professional goal of data reuse. Three use cases relating to 3D Pottery, radiocarbon, and GIS data were created. The pilot study has proven that the methodology works and could be applied in future research. This article discusses the application of the quality-in-use approach for evaluating the quality of digital archaeological archives, as well as presenting the methodology and the results of the pilot study