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An investigation of the impacts of unrestricted cattle access to watercourses on freshwater physicochemical and microbial parameters
Get PDFWhere pastoral agriculture dominates, the practice of allowing livestock access to farmland watercourses as a cheap and low maintenance source of drinking water has been shown to have an adverse impact on water quality. In Ireland, agriculture, which is predominantly cattle-based, has been linked to the downward trend in water quality observed in recent decades, which conflicts with the goals of the Water Framework Directive. However, the research investigating the potential impacts of cattle access to watercourses on freshwater systems has predominantly been conducted in the USA and Australasia. In these regions, climate and farming practices typically contrast with those observed in Ireland and in Europe, thus making comparison difficult. This study aimed at contributing to an understanding of the impacts of cattle access to watercourses on freshwater systems in the Irish setting. Specifically, the current study investigated the impacts of cattle access to streams on freshwater abiotic parameters (i.e. nutrients, sediment) and on freshwater faecal contamination. It also addressed the efficacy of streamside fencing as a mitigation measure for such impacts. The findings of this study showed that faecal contamination in watercourses draining agricultural areas in Ireland is widespread. Escherichia coli (E. coli) concentrations in the streambed sediment compartment were in the order of 103 to 104 CFU g dry wt-1 at stream reaches with no cattle access, during grazing season. However, at stream reaches with unrestricted cattle access, E. coli sediment concentrations were significantly higher, with maximum average concentrations of 1.6 x 107 CFU g dry wt-1 in mid-grazing season. Sediment E. coli concentrations were found to decrease but persist in post-grazing season, with concentrations at upstream reaches of up to 103 CFU g and up to 105 CFU g dry wt-1 at cattle access sites. Furthermore, the study found a significant negative correlation between the Riparian Habitat Index scores of the sites, which reflect the intensity of cattle access impact (and whereby a lower score indicates higher site degradation) and E. coli sediment concentrations in mid-grazing season. Nutrient (TP, TN and OC) reservoirs in sediments at cattle access sites were assessed. Results here indicate that cattle access to watercourses does not generally result in localised nutrient accumulation in streambed sediments. However, this study found a significant positive relationship between cattle density at the access sites and all three nutrient concentrations in the silt and clay fraction of the sediments. The results suggest that while cattle access may contribute to sediment nutrient reservoirs, rapid flushing downstream of nutrients at access sites may occur. Additionally, results suggest that sediment nutrient concentrations in agricultural streams are mainly driven by diffuse pollution at the catchment scale. Potential changes in water quality parameters during cattle in-stream activity were assessed in a near-real time experiment which showed that cattle access led to significant increases in water loads of E. coli bacteria, TSS and NH4-N. While increases were observed in TP loads, these were not significant in the context of the natural variation at the experimental site. NO3-N and SRP did not show significant variation in response to cattle in-stream activity. A short study on the effects of streamside fencing showed a positive effect in streambed sediment concentrations of E. coli and nutrients. However, this study also highlighted the need of adopting a site-specific, holistic approach that combines cattle exclusion measures with other measures to control diffuse pollution if cattle-based agriculture pressures are to be successfully managed. The current research has thus demonstrated that cattle access to watercourses contributes to both faecal and nutrient contamination of freshwaters, and that while microbial pollution is mainly governed by field-scale management, nutrient pollution is driven by catchment-scale practices. Results presented here support the implementation of fencing to exclude cattle from watercourses; however, this needs to be considered as part of wider, integrated catchment management plans. The study contributes to the literature describing agricultural pressures in headwater streams and provides relevant information for stakeholders and policy makers
A Qualitative Analysis of Female Protagonists in Popular Science Fiction Cinema, From 2010 to 2019
Get PDFThis thesis investigates the representation of female protagonists in the top grossing science fiction films worldwide over the course of a decade, 2010 to 2019. While there has been an emphasis on the lack of female representation in cinema in quantitative terms, this research aims at addressing a dearth in the knowledge by focusing qualitatively on the representations being created. The research determines whether these female protagonists are objectified in line with historical trends in mainstream cinema and whether any progress has been made in terms of shifting representations. It questions representations of femininity, agency, and diversity by investigating the portrayals found in the corpus of films. Through textual analysis, incorporating elements of discourse analysis, thirty-one films are analysed. The research determines that women’s representations within the genre largely uphold patriarchal ideals. In most cases this tendency reflects cultural anxieties relating to shifting definitions of gender and identity and results in stereotypical representations of femininity. The majority of female protagonists also remain objectified on-screen with the “male gaze” still present in this contemporary corpus of films. However, the research also acknowledges a positive shift occurring, with a number of exceptions to this general rule. Women’s representations are sometimes positively linked to STEM subjects and concentrated efforts have been made to create progressive representations in some instances. These alternative representations are often linked to an increase in the number of key female crew members involved in the film production process, most notably as directors and/or writers. This research claims that while mainstream cinema continues to offer stereotypical patriarchal hegemonic representations of women, when women’s voices are privileged and they appear in key production roles more progressive representations tend to occur
Modulation of Purinergic Contractility in the Murine Detrusor
No full textβ3-adrenoceptor (β3-AR) agonists, such as Mirabegron, relax the urinary bladder and have been approved for the treatment of overactive bladder (OAB) since 2012. However, the exact cellular mechanisms that mediate the effects of these drugs are still unclear. Contraction of the bladder is regulated by release of acetylcholine, and to a lesser extent adenosine triphosphate (ATP), from parasympathetic nerves. It is known that β3-AR agonists can inhibit acetylcholine responses in the bladder, but their effects on ATP responses have not been systematically investigated. This is an important issue, as ATP responses are upregulated in patients with OAB. The purpose of this study was to examine the cellular mechanisms underlying β3-AR-induced inhibition of bladder contractions, with a particular focus on the role of a novel cyclic adenosine monophosphate (cAMP) effector, exchange protein directly activated by cAMP (EPAC).
Isometric tension recordings were obtained from strips of murine detrusor and electrophysiology studies were performed on both freshly dispersed murine detrusor myocytes and HEK cells transfected with P2X1 receptor plasmids, respectively. The key findings of this study were: 1) β3-AR agonists were more effective at inhibiting purinergic contractions compared to cholinergic contractions of the murine bladder; 2) cholinergic and purinergic contractions of the bladder were inhibited by activation of protein kinase A (PKA) and EPAC; 3) EPAC-induced inhibition of purinergic responses in the bladder were attenuated by Kv7 channel blockers; 4) EPAC directly inhibited P2X1 receptors, and amino acids located at positions 21-23 on the N-terminus of the P2X1 receptor are critical for this effect and; 5) Rac1, a member of the Rho family of small GTPases, may be involved in EPAC-mediated inhibition of purinergic responses.
These data suggest that β3-AR agonists reduce the amplitude of ATP- induced contractions of the bladder via activation of EPAC, which inhibits P2X1 receptors on detrusor myocytes
The World is our Oyster: The Benefits of International Experiences in Higher Education
Get PDFCOVID-19 imposed limitations on international travel for all of society. In academia, this has impacted on the ability of staff and students to participate in international conferences, Erasmus exchange and mobility programmes and other international activities that had been part of their Higher Education experience. In this paper, we critically reflect on two international activities that we were involved in with students and highlight how a number of benefits and experiences cannot be replicated in virtual contexts. To this end we draw from previous reflections by staff and students that formed part of a number of small research projects and presentations that resulted from international travel. This has informed the planning for and design of extra-curricular activities, as well as programme development in our institution. For music graduates seeking to develop a career in performance or engage in interdisciplinary teams, international experiences and cultural competencies prepare them for a career in the global industries. Despite the impact of COVID-19 restrictions on international travel this paper highlights the ongoing potential of international projects to impact positively on staff and students’ experience in Higher Education
Port na bPucaí: Representations of solitude, isolation and otherworldly encounters in Irish poetry and folk theatre
Get PDFPort na bPucaí or the tune of the fairies is a well-known piece in Irish traditional music that is reputed to have been heard by a musician during a period of solitude. It reflects a common motif in Irish folklore whereby individuals are inspired by or develop their craft and skills in solitude with suggestions of spiritual otherworldly assistance. The tale and tune are represented in Irish poetry and folk theatre. In this paper, I critically consider how the work of Irish poet Séamus Heaney and the theatre company Siamsa Tíre, the National Folk Theatre of Ireland incorporates or is inspired by folklore and music related to solitude, isolation and encounters with an otherworld or spiritual dimension. Although there is no connection between the poet and the theatre company, I draw on three examples in which Heaney and Siamsa Tíre draw on similar points of inspiration from folklife and lore, reflecting the link between literature, art and folk culture. The examples reflect themes of solitude and isolation, both in relation to individuals and communities, and the creativity, wisdom and understanding attributed to moments of isolation. The article also reflects on the creative process and the importance of solitude for the artists
Phenological shifts in lake stratification under climate change
Get PDFOne of the most important physical characteristics driving lifecycle events in lakes is stratification. Already subtle variations in the timing of stratification onset and break up (phenology) are known to have major ecological effects, mainly by determining the availability of light, nutrients, carbon and oxygen to organisms. Despite its ecological importance, historic and future global changes in stratification phenology are unknown. Here, we used a lake climate model ensemble and long-term observational data, to investigate changes in lake stratification phenology across the Northern Hemisphere from 1901 to 2099. Under the high greenhouse-gas-emission scenario, stratification will begin 22.0 ± 7.0 days earlier and end 11.3 ± 4.7 days later by the end of this century. It is very likely that this 33.3 ± 11.7 day prolongation in stratification will accelerate lake deoxygenation with subsequent effects on nutrient mineralization and phosphorus release from lake sediments. Further misalignment of lifecycle events, with possible irreversible changes for lake ecosystems, is also likely
The Sync-Up Process to Improve the Multiple Stakeholder Communication of Requirements Analysis in Embedded Medical Software Development
Get PDFThe development of embedded medical software is different from ordinary software development as it needs to be coordinated with the hardware development. A typical
embedded system project involves multiple stakeholders such as the business unit, software developers, hardware engineers and firmware developers. Agile methods have
been successfully adopted in generic software engineering, and more recently in embedded medical software development.
In this research, a systematic review has been performed to identify the challenges of embedded medical and safety-critical software development domains. From the challenges
identified, this research focuses on the challenge of multiple stakeholder communication in
embedded medical software development. Additionally, agile practices which have been successfully adopted in the embedded safety-critical domains have been investigated.
This thesis describes the development and evaluation of a process (Sync-Up) to improve multiple stakeholder communication for embedded medical software development during requirement analysis.
Through this research, the following contribution to knowledge has been made in the area of embedded medical domain. The development of the Sync-Up process to assist
multiple stakeholder communication of embedded medical software development. The Sync-Up process is evaluated through both expert review by leading experts, and a case
study conducted in an embedded company. Findings from the evaluations undertaken show a positive outcome during the requirement analysis phase of the Sync-Up process