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International registry on aortic balloon occlusion in major trauma: Partial inflation does not improve outcomes in abdominal trauma
(Elsevier, 2023-08-30) Paran Maya; McGreevy, David; Horer. Tal M; Khan, Mansoor; Dudkiewicz, Mickey; Kessel, Boris; the ABO Trauma Registry research group
Background
Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a method for temporary hemorrhage control used in haemodynamically unwell patients with severe bleeding. In haemodynamically unwell abdominal trauma patients, laparotomy remains the initial procedure of choice. Using REBOA in patients as a bridge to laparotomy is a novel option whose feasibility and efficacy remain unclear. We aimed to assess the clinical outcome in patients with abdominal injury who underwent both REBOA placement and laparotomy.
Methods
This is a retrospective study, including trauma patients with an isolated abdominal injury who underwent both REBOA placement and laparotomy, during the period 2011–2019. All data were collected via the Aortic Balloon Occlusion Trauma Registry database.
Results
One hundred and three patients were included in this study. The main mechanism of trauma was blunt injury (62.1%) and the median injury severity score (ISS) was 33 (14–74). Renal failure and multi-organ dysfunction syndrome (MODS) occurred in 15.5% and 35% of patients, respectively. Overall, 30-day mortality was 50.5%. Post balloon inflation systolic blood pressure (SBP) >80 mmHg was associated with lower 24-h mortality (p = 0.007). No differences in mortality were found among patients who underwent partial occlusion vs. total occlusion of the aorta.
Conclusions
Our results support the feasibility of REBOA use in patients with isolated abdominal injury, with survival rates similar to previous reports for haemodynamically unstable abdominal trauma patients. Post-balloon inflation SBP >80 mmHg was associated with a significant reduction in 24-h mortality rates, but not 30-day mortality. Total aortic occlusion was not associated with increased mortality, MODS, and complication rates compared with partial occlusion.
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Soundscape, Weeping Scenes and the Constructs of Resistance in Revelation 18
(Stellenbosch : Stellenbosch University, 2024-12) Michael, Matthew; Punt, Jeremy; Stellenbosch University. Faculty of Theology. Dept. of Old and New Testament.
The dissertation engages the acoustic poetics of the book of Revelation by examining the strategic use of sounds as a subversive instrument of resistance in Revelation 18. It interrogates Revelation in the construct of its animated soundscape, and the lethal appropriation of this sensory space for its subversive polemics against Rome in the double ciphers of Babylon and the Prostitute. While past scholarship has generally ignored the central importance of weeping scenes in the study of Revelation, this dissertation underscores the acoustic poetics of the weeping scenes and the subversive deployment of city-laments for the purpose of resistance in Revelation 18. Using a sound-centred approach, it repositions the studies in Revelation, and apocalyptic literature in general for an interdisciplinary conversation with the emerging field of sound studies. Thus, the first chapter of the dissertation introduces the critical importance of soundscape and weeping scenes in the book of Revelation, the sound-driven hermeneutics, the research questions, the research scope and objectives respectively. Chapter Two examines the rhetorical character of weeping scenes in the book of Revelation in direct conversation with the sonic enthronement of the divine voice, the weaponised acoustics of its Christology, the sonic representation of a traumatised church, the aural operations of its punitive angels, the exploitative acoustics of its ecology, and the auditory character of its territorial spaces. Chapter Three focuses on Revelation 18 through its acoustic background, genre, literary environment, chiastic structure, the interactive character of the weeping voices, and the distinctive sonic features of Revelation 18 as an important weeping scene in the construct of a city-lament. In Revelation 18, we encounter the entire empire of Rome in mourning, and the vocal protest of its hegemonic control, powers and global order. In particular, the acoustics of this city-lament projects the defeat of God’s enemies whose cries in Revelation 18 resonate with the earlier cries of the martyrs, and fulfil their longing for vengeance (6:9-10 cf. 7:10; 8:2-3). Chapter Four describes the important acoustic devices in Revelation 18 which are creatively deployed to the task of resistance. In this site of great resistance, Revelation 18 presents subversively the loud acoustics of angelic protests, the polemics of dystopian sounds, the sonic attacks of boycotts, the alienating power of sonic sanctions, the acoustic design of mimicries, the polemic identities of submerged voices, and the sonic constructs of disability and animal sounds in cohesive attacks against Rome. In its resistance against the established order, the poetics of Revelation 18 harnessed the lethal character of lament that called defiantly for the destruction of the status quo, the birth of a new world, and the dramatic reordering of the present society. Lastly, Chapter Five concludes the findings of this dissertation which are primarily centred on the acoustic importance of weeping scenes in the book of Revelation, the lethal character of its soundscape as instrument of resistance, the polemic construct of Revelation 18 as a city-lament, the interactive symphony of Revelation 18, and its contribution to the acoustic agenda of apocalyptic literature.
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The mediating role of Self-efficacy and the moderating role of Family Supportive Organisational Perception o n the relationship between Work-Life Balance Conflict and Emotional Exhaustion
(Stellenbosch : Stellenbosch University, 2024-12) Mhlauli, Kwang; de Wet, Marietha; Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Industrial Psychology.
The world has seen unparalleled change as a result of the COVID-19 virus. The epidemic has unquestionably had a significant impact on employees' work schedules, which has affected how they carry out their obligations. There has not yet been much research on these recent phenomena. This study investigated the impact of work-life balance (WLB) conflict on emotional exhaustion among South African employees during the COVID-19 pandemic, considering the mediating role of self-efficacy and the moderating influence of family-supportive organisational perception (FSOP). Drawing on literature emphasising the challenges of remote work and the importance of organisational support, the study addressed gaps in understanding the specific dynamics of WLB conflict, emotional exhaustion, self-efficacy, and FSOP within the South African context.
The research methodology employed a quantitative approach, utilising Partial Least Square-Structural Equation Modeling (PLS-SEM) to analyse data. The research design adopted an explanatory approach with a correlational, cross-sectional design. Data collection was conducted through an online questionnaire distributed via professional networking platforms, with a sample size of 451 respondents determined using a non-probability sampling technique.
The findings revealed a significant relationship between WLB conflict and emotional exhaustion, suggesting that employee emotional exhaustion is influenced by WLB conflict to some extent. Furthermore, the moderating role of FSOP between WLB conflict and emotional exhaustion is significant. However, the study did not find evidence to support the mediation of self-efficacy in the relationship between WLB conflict and emotional exhaustion. The effects of work interference with personal life (WIPL) on self-efficacy and self-efficacy on emotional exhaustion were statistically nonsignificant. The findings contribute to both theoretical and practical knowledge by shedding light on the mechanisms through which WLB conflict influences emotional exhaustion and the roles of self-efficacy and FSOP in mitigating its effects. The study offers insights for organisations to support employee well-being, enhance productivity, and adapt to the challenges of remote work, ultimately fostering a healthier and more sustainable work environment.
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The Relationship between Authentic Leadership, Job Demands, Job Resources, Psychological Capital, and Burnout in a Call Centre Work Environment
(Stellenbosch : Stellenbosch University, 2024-12) Meyer, Elda Helena; Roux, Shayne; Van der Bank, Francois; Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Industrial Psychology.
Developed countries often rely on call centres to offshore their business to South Africa, enabling organisations to reduce costs while reaping the benefits of continuous service delivery. This however comes at the expense of employee well-being since burnout is a widespread issue in call centres and is linked to high turnover rates among call centre agents. The burnout syndrome is a decades-old issue and the continuously growing interest in the phenomenon stresses that it is a continuous and significant global crisis. Failure to acknowledge the prevalence of burnout can negatively impact the bottom line and impede the ability of call centre agents to function productively in the work environment. For call centres to remain sustainable in the digital age, their human capital must be prioritised. The main objective of this study was to develop and test a structural model that explicates organisational and individual factors that influence burnout among call centre agents. These factors include Authentic Leadership, Job Demands, Job Resources, and Psychological Capital.
An ex post facto correlational research design was used in this study to examine the relationships between the variables. Call centre agents employed in a particular organisation in Johannesburg, Gauteng were the target population, and a non-probability convenience sampling method was employed. The questionnaire was completed by a sample of n = 237. Item analysis was conducted to examine the reliability of the measuring instruments, and the fit of the comprehensive measurement and structural model were evaluated using Confirmatory Factor Analysis (CFA) and Structural Equation Modelling (SEM), respectively. Support for the close fit null hypothesis was found and the evidence considered in totality indicated an acceptable solution. The results provided support for six of the eight hypothesised relationships in the structural model. Statistically significant relationships were found between the following variables: Authentic Leadership and Job Demands (-); Authentic Leadership and Job Resources (+), Job Demands and Burnout (+); Job Resources and Burnout (-); Job Resources and Psychological Capital (+); and Psychological Capital and Burnout (-). Support was however not found for the hypothesised relationships between Authentic Leadership and Psychological Capital (+), and Job Demands and Psychological Capital (-).
This research contributes to the body of knowledge regarding the antecedents of burnout and provides recommendations for organisational interventions aimed at managing and preventing the phenomenon. The findings can potentially contribute to the development of a more extensive understanding of the nature of burnout in the South African call centre industry and may narrow the misalignment between the interests of employees and organisations.
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Studies on the genetic parameter estimates and trends to reduce reproductive wastage in the Tygerhoek Merino sheep resource flock
(Stellenbosch : Stellenbosch University, 2024-12) Meijboom, Samuel Mendel; Cloete, Schalk; Nel, Cornelius; Dzama, Kennedy; Stellenbosch University. Faculty of AgriSciences. Dept. of Animal Sciences.
Reproductive wastage has been and continues to be a major constraint to production in the South African small stock industry. Reproductive wastage is a large contributor to income loss and raises welfare concerns for the sheep industry worldwide. This study evaluated different methods to minimize reproductive wastage by estimating phenotypic and genetic parameters, as well as analyzing genetic trends for ewe reproduction and lamb survival in a well recorded Merino resource flock. Furthermore, the study also considered the effect of the ambient environment on ewe conception to curb reproductive wastage. The Tygerhoek Merino resource flock has detailed records for ewe reproduction and lamb survival trait complexes. The research farm is also close to an official weather station, which allows for long-term climate data to construct a temperature-humidity index (THI) as a descriptor of the ambient environment. This placed the flock in a unique position to allow for a comprehensive analysis on strategies to minimize reproductive wastage. The first aim of the study was to conduct an extensive analysis on the composite trait; number of lambs weaned (NLW) and its individual components (conception (CON), ewe rearing ability (ERA) and litter size (LS)). The genetic relationships of NLW with the components were examined and yielded no unfavorable correlations. It also suggested that component traits (CON, ERA and LS) should be emphasized to increase reproductive efficiency instead of only focusing on NLW. The study then focused on the effect of the ambient environment on CON. Heat stress has had a negative effect on CON in dairy cattle, however, similar studies have not been repeated in sheep. Hence, this study aimed at being one of the first studies to consider the THI and its effect on CON in Merino ewes. Increased levels of heat stress, as reflected by an increased THI, exhibited a clear negative effect of heat and a more prominent effect of accumulative heat on the CON of ewes. Apart from ewe reproduction, another comprehensive genetic analysis was conducted on the early stages of lamb survival. This analysis considered the traits lamb survival at birth and survival until 3 days of age. The aim of this was to minimize reproductive wastage by targeting survival as a trait of the lamb, rather than the more common approach of concentrating on ewe reproductive traits. The thesis conformed with previous literature by reporting low heritability estimates for both ewe reproduction and lamb survival traits. However, despite low heritability estimates, genetic gain can be achieved over numerous generations. It is recommended that reproductive efficiency must be included in selection objectives and, where possible, the early stages of lamb survival must also be considered to minimize reproductive wastage. Derived genetic trends reflected slow change (<0.2% of the overall mean per annum), generally in the desired direction. These results were expected as the experimental protocol followed precluded directed selection for reproduction or lamb survival. These results conformed to previous studies suggesting that reproductive efficiency and lamb survival can be increased while still maintaining a high standard of wool production. It also identified keyways to minimize reproductive wastage through concentrating on traits of the ewe as well as of the lamb.