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The Variation in Groundwater Microbial Communities in an Unconfined Aquifer Contaminated by Multiple Nitrogen Contamination Sources
No full textAquifers provide integral freshwater resources and host ecosystems of largely uncharacterized, truncated endemic microorganisms. In recent history, many aquifers have become increasingly contaminated from various anthropogenic sources. To better understand the impacts of nitrogen contamination on native groundwater ecosystems, 16S rRNA sequencing of the groundwater microbial communities was carried out. Samples were taken from an aquifer known to be contaminated with nitrogen from multiple sources, including fertilizers and wastewater treatment plant effluents. In total, two primary contaminants were identified: NH4+ (<0.1–3.7–26 mg L−1 NH4+ minmedian-max), and NO3− (<0.01–18–150 mg L−1 NO3− min-median-max). These contaminants were found to be associated with a decrease/increase in microbial species richness within affected groundwater for NH4+/NO3−, respectively. Important phyla were identified, including Proteobacteria, which had the highest abundance within samples unaffected by NH4+ (36–81% NH4+ unaffected, 4–33% NH4+ affected), and Planctomycetes (0.05–10% NH4+ unaffected, 43–72% NH4+ affected), which had the highest abundance within the NH4+ affected samples, likely due to its ability to perform anaerobic ammonia oxidation (ANAMMOX). Planctomycetes were identified as a potential indicator for the presence of NH4+ contamination. The analysis and characterization of sequencing data alongside physicochemical data showed potential to increase the depth of our understanding of contaminant behavior and fate within a contaminated aquifer using this type of data and analysis
The source of cell-free mitochondrial DNA in trauma and potential therapeutic strategies
No full textMitochondria play a key role in the pathophysiology of post-injury inflammation. Cell-free mitochondrial DNA (cf-mtDNA) is now understood to catalyse sterile inflammation after trauma. Observations in trauma cohorts have identified high cf-mtDNA in patients with systemic inflammatory response syndrome and multiple organ failure as well as following major surgery. The source of cf-mtDNA can be various cells affected by mechanical and hypoxic injury (passive mechanism) or induced by inflammatory mechanisms (active mechanism). Multiple forms of cf-mtDNA exist; mtDNA fragments, mtDNA in microparticles/vesicles and cell-free mitochondria. Trauma to cells that are rich in mitochondria are believed to release more cf-mtDNA. This review describes the current understanding of the mechanisms of cf-mtDNA release, its systemic effects and the potential therapeutic implications related to its modification. Although current understanding is insufficient to change trauma management, focussed research goals have been identified to pave the way for monitoring and manipulation of cf-mtDNA release and effects in trauma
The integration of mobile learning in student interpreters’ out-of-class learning in China
No full textInformation and Communication Technology (ICT) has impacted interpreter education for decades. However, the adoption of recent mobile technology is under-researched. The purpose of this mixed methods study involving 460 Chinese student interpreters is to understand the integration of mobile technologies in out-of-class learning. This thesis focuses on describing mobile learning opportunities and obstacles among postgraduate student interpreters in China’s universities and exploring how student interpreters use mobile learning beyond class-based contexts. Research data were concurrently collected from a quantitative and a qualitative phase, and three methods were utilised: survey, interview and diary. This thesis found that (a) students’ opportunities of mobile learning varied by background, perceived support and students’ characteristics; and they had a few common obstacles; (b) Chinese student interpreters in general demonstrated professional and creative use of mobile tools and resources in their out-of-class learning (c) student interpreters showed behavioural patterns in their use of devices and media in out-of- class mobile learning. Central to these findings are the conceptualised mobile learning environments in interpreter education and modes of interactions between students and their mobile learning environment. This thesis illuminates the theoretical development of mobile-assisted interpreter education (MAIE) which is a hot research topic in the field of translation and interpreting studies (T&I) recently in China and worldwide. The discussions will make this thesis a valuable source for both researchers and educators to reflect upon the practical implications of the current research for curriculum modification, learning support and improving teaching and learning in interpreter education programs
Visible and vocal: Black Women in Eighteenth Century Britain c. 1707-1834
No full textThis thesis examines the lives of women of African or Afro-Caribbean race or descent, who were living in Britain during the long eighteenth century. These women were often previously enslaved themselves, or descendants of enslaved people. Despite people of colour having an uncertain legal identity throughout this century, the default status of individuals actually seems to have been that of freedom, rather than continual enforced slave status on British soil. It was entirely possible for Black women to live ordinary, free lives, similar in many ways to those of their white female counterparts of the same age and class. By examining criminal trial transcripts, it is apparent that women of colour appeared as prosecutors, defendants and witnesses in court proceedings. Many other records were also used to show that Black women were found in many different elements of society. They were present in both urban and rural white communities, and were a part of their own Black communities too. Women of colour were able to be part of working class and middle class society, and some women skirted around the edge of upper class social groups. However, whitewashing certainly occurred in culture and art. The stories of these women and their ability to possess agency, independence and freedom contributes to a more thorough understanding of long eighteenth century Transatlantic history
Title: Blood flow restricted exercise training: Perspectives of people with chronic obstructive pulmonary disease and health professionals
No full textObjective: This descriptive qualitative study explored perspectives of people with chronic obstructive pulmonary disease (COPD) and health professionals concerning blood flow restricted exercise (BFRE) training. Methods: People living with COPD and health professionals (exercise physiologists, physiotherapists, and hospital-based respiratory nurses and doctors) participated in interviews or focus groups, which included information about BFRE training and a facilitated discussion of positive aspects, barriers and concerns about BFRE training as a possible exercise-based intervention. Sessions were audio-recorded, and transcript data analysed using inductive content analysis. Results: Thirty-one people participated (people with COPD n = 6; health professionals n = 25). All participant groups expressed positive perceptions of BFRE as a potential alternative low-intensity exercise mode where health benefits might be achieved. Areas of overlap in perceived barriers and concerns included the need to address the risk of potential adverse events, suitability of training sites and identifying processes to appropriately screen potential candidates. Discussion: While potential benefits were identified, concerns about determining who is safe and suitable to participate, delivery processes, health professional training and effects on a variety of health-related outcomes need to be addressed before implementation of BFRE training for people with COPD
Modeling weathering pathways and processes of the fragmentation of salt weathered quartz-chlorite schist
No full textThe relationship between the rate of rock breakdown and environmental and geological factors must be understood in order to establish the conditions under which weathering limits erosion. In this study qualitative and quantitative models of the rock fragmentation process are fitted to previously published data obtained from laboratory salt weathering trials of quartz-chlorite schist. Weathering was modeled as a combination of (1) a fragmentation event that fragments the parent particle into a number of daughter particles while preserving mass, and (2) a fracture probability, that determines the probability that a fragmentation event will occur in a given time period. We show that observations of the complex breakdown of salt weathered schist are consistent with model assumptions of a simple fracture geometry model and an increase in fracture probability with time. For the fragmentation geometry the best fit to the experimental data was achieved by assuming that each fragmentation event involves splitting of the parent particle into two daughter fragments of equal volume. For the fragmentation rate the data could best be described with a fracture probability, and hence the weathering rate, that increased linearly with time. This paper shows that it is possible to use a physically based fragmentation model to infer the process of fragmentation for individual particles using a time evolving particle size distribution for the weathering rock fragments
Access to and Use of Internet and Social Media by Low-Morbidity Stroke Survivors Participating in a National Web-Based Secondary Stroke Prevention Trial: Cross-sectional Survey
No full textBackground: eHealth applications for stroke are a growing area of research that has yielded promising results. However, little is known about how stroke survivors engage with the internet, social media, and other digital technologies on a day-to-day basis. Objective: This study had three main objectives: to describe the type, frequency, and purpose of technology use among a cohort of low-morbidity stroke survivors; to investigate associations between social media use and participant factors, including sociodemographics, physical function, and independence in activities of daily living; and to investigate associations between stroke-related health risk factors and the use of the internet to search for health and medical information. Methods: This study is a secondary analysis of data obtained during a national randomized controlled trial—Prevent 2nd Stroke. The participants were stroke survivors recruited from 2 Australian stroke registries who completed 2 telephone-administered surveys to collect data on demographics and stroke characteristics; health risk factors (diet quality, physical activity, blood pressure medication, alcohol intake, anxiety and depression, and smoking status); physical functioning; independence in activities of daily living; and questions about what technology they had access to, how often they used it, and for what purposes. Participants were eligible if they had no more than a moderate level of disability (modified Rankin score ≤3) and had access to the internet. Multivariable logistic regression was used to assess the associations between social media use and sociodemographics, physical function, and independence in activities of daily living as well as associations between stroke-related health risk factors and the use of the internet to search for health and medical information. Results: Data from 354 participants were included in the analysis. Approximately 79.1% (280/354) of participants used the internet at least daily, 40.8% (118/289) accessed social media on their phone or tablet daily, and 46.4% (134/289) looked up health and medical information at least monthly. Women were 2.7 times more likely to use social media (adjusted odds ratio 2.65, 95% CI 1.51-4.72), and people aged >75 years were significantly less likely to use social media compared with those aged <55 years (adjusted odds ratio 0.17, 95% CI 0.07-0.44). Health risk factors were not found to be associated with searching for health- or medical-related information. Conclusions: The internet appears to be a viable platform to engage with stroke survivors who may not be high-morbidity to conduct research and provide information and health interventions. This is important given that they are at high risk of recurrent stroke regardless of their level of disability. Exploring the technology use behaviors and the possibility of eHealth among survivors who experience higher levels of morbidity or disability because of their stroke is an area of research that warrants further study
Addiction perceptions among users of smokeless or combustible tobacco attending a tertiary care hospital in India
No full textIntroduction: Addiction plays a key role in continued tobacco use. The study assessed association of perceived personal addiction and the perceived addictiveness of different forms of tobacco with type of tobacco product used, demographic characteristics and socio-cultural factors. Methods: A cross-sectional survey of 607 adult tobacco users with age 18 years and above attending a general medicine out-patient department was conducted. Participants were asked questions on perceived personal addiction to tobacco use and perception of addiction on tobacco products. Logistic regression was applied to investigate the association between demographic characteristics, type of tobacco, socio-cultural factors and addiction perceptions. Results: The odds of perceived addiction (PA) were lower among smokeless tobacco (SLT) users [OR (95% CI): 0.57 (0.37, 0.89) P = 0.01]. An increase in the odds of PA was seen as age increased [OR (95% CI):1.02 (1.00, 1.03) P = 0.01] and participants with secondary education and above had higher odds of PA compared to participants with no formal education [OR (95% CI): 1.68 (1.09, 2.58) P = 0.02]. The odds of perceiving SLT products to be addictive was lower among SLT users [OR (95% CI): 0.48 (0.30, 0.75) P = 0.002)] compared to combustible tobacco users. The odds of perceiving SLT products to be addictive was lower [(OR (95% CI): 0.35 (0.18, 0.67) P = 0.002)] among females. Participants with secondary education and above had higher odds of perceiving combustible [OR (95% CI): 1.80 (1.17, 2.77) P = 0.008)] and SLT products [OR (95% CI): 1.98 (1.20, 3.30) P = 0.008)] to be addictive compared to no schooling. Discussion and Conclusions: There is a need to raise awareness in India of the addictiveness of tobacco, particularly for users of SLT, younger people and those with less education
Visualization of the vacancy-wind effect occurring in chemical diffusion and ionic conductivity in solids
No full textNet fluxes of vacancies commonly occur during chemical interdiffusion in alloys, ionic conductivity and the annealing out of radiation damage. When atoms with different jump rates diffuse in a net flux of vacancies the phenomenon of the vacancy-wind effect will occur. This
effect, first discovered by the late Dr John Manning, is a subtle phenomenon arising from a disturbed distribution of vacancies with respect to a given moving atom or species of atom. In this paper, the vacancy-wind effect is discussed and its visualization, performed for the first time by computer simulation, is demonstrated
The value relevance of corporate carbon abatement initiatives
No full textClimate change is one of the most debated global issues of the past few decades. Corporations are reacting to climate change by adjusting strategies, engaging in carbon management practices and making climate-related disclosures. The evolving carbon accounting literature provides certain insights into corporate carbon practices and the capital market effects of firm carbon emissions, but few studies have examined firms’ commitment to the climate change battle. This thesis attempts to narrow this gap in the literature by investigating the economic consequences of carbon abatement initiatives in two empirical studies. The first empirical study addresses two research questions. The first is whether and how firm investment in carbon abatement initiatives affect firm value. This question is important because the findings will inform corporate managers and investors about the financial implications of firm carbon abatement investment (CAI). Drawing on the resource-based view, it is argued that firm CAI generates benefits to firms but also involves significant costs. The net effect of firm CAI on firm value depends on whether the benefits outweigh the costs or vice versa. Using a sample of companies from the US, the UK and Australia from 2010 to 2016, the first empirical study provides evidence that firm CAI is negatively related to firm value. The finding indicates that investors are concerned about the high costs of CAI. The second research question is whether the valuation effect of firm CAI varies with the carbon policy regimes of the countries in which firms operate. This question is important for policymakers to observe the influence of national climate policies on the perceived value of firm CAI. Using a comparison method, it is found that while firm CAI is viewed as value-destroying by US investors, it enhances firm value in the UK and has no observable valuation effects in Australia. The results indicate that the valuation effect of CAI is dependent on the institutional settings of the firms. The second empirical study of this thesis investigates the moderating effects of country-level climate risks on the relationship between firm CAI and firm value. Climate risk has attracted great attention from capital market regulators, investors and consolation professionals in recent years because of its financial implications for firms and investors. Based on the literature affirming that firm investment in corporate social responsibilities (CSR) and environmental management plays a role in risk management, it is argued that CAI may be a measure taken by firms to manage climate risk. Because the benefits of risk management are more significant when the risk level is high, it is expected that CAI may be less value detrimental in a business environment with higher climate risk. Based on a sample of firms from 24 countries, the results suggest that firms dwelling in countries with a higher level of transitional risk (e.g., regulatory, litigation and reputational risk) tend to undergo less value decrement. However, physical risk does not have the same significant influence. This study enhances the understanding of the valuation of firm CAI and emphasises the importance of considering the country-level climate risk factors when examining the valuation effects. The thesis contributes to the social and environmental accounting literature by empirically testing the value relevance of CAI in various institutional contexts and examining the relationship from a risk management perspective. The study also provides potential implications for policymakers, capital market regulators, accounting standard settings, investors, managers, financial analysts and fund managers