Southern African palaeoclimates and variability : the story from stalagmites, pollen and coral.

Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2005.Compared to extensive study in the northern hemisphere, very little is known of southern African palaeoclimates. This study aimed to extend understanding of the nature of and controls on southern African palaeoclimates of the last 40 000 years. Through a study of the approximately 20 000 year long Makapansgat and Wonderkrater palaeoclimatic records, and an extensive literature review of southern African palaeoclimatic studies, a number of common rainfall and temperature fluctuations were detected across the summer rainfall region. Based on these trends, general models of rainfall and temperature changes over time were developed for the region. The analysis of a coral core, derived from a Porites lutea head from Sodwana Bay, covering the last 116 years, indicated higher frequency climatic fluctuations over the last century. Climatic variability on the long- and short-term could then be related to known atmospheric processes through application of the Tyson (1986) model for southern Africa atmospheric circulation. North-south shifts in mean circulation dominate climatic variability in the region but there are also regular disturbances to this mean, such as in the form of the EI Nino - Southern Oscillation. The fluctuations seen in present and palaeoclimatic records are the result of a complex interaction between internal and external mechanisms of climate change. Wavelet analyses of recorded and proxy climatic datasets highlighted the cycles which dominate southern African climatic variability on timescales from years to millennia. The causes of these cycles were then assessed in the context of established solar, atmospheric and oceanic models. Wavelet analyses also provided an indication of frequency changes over time and were therefore useful for detecting climate change. An analysis of proxy and recorded climatic datasets for southern African rainfall over the last 100 years indicated a frequency modulation of the 18 year rainfall cycle, which was first described by Tyson (1971). This variation may be related to anthropogenic climate change. It became apparent from this study that there is a need for increased scientific interest in the palaeoclimatic trends of the region. The number of continuous, high-resolution datasets needs to be increased to allow for comparison and confirmation of various trends with records from sites across the globe. An understanding of the nature of regional and global teleconnections is essential before reliable climate change models can be established. There is also a need for further understanding of short-term southern African climate variability on inter-annual timescales.It is only once we have an understanding of the natural climatic variability of the region ,and its inherent cyclicity,that we can begin to distinguish the impact of anthropogenic activities on climate

The value of liquid biopsy in the diagnosis and staging of hepatocellular carcinoma : A systematic review

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Apolipoprotein E Genetic Variation and Its Association With Cognitive Function in Rural-Dwelling Older South Africans

Apolipoprotein E (APOE) ε4 allele carrier status is well known for its association with an increased likelihood of developing Alzheimer’s disease, but its independent role in cognitive function is unclear. APOE genetic variation is understudied in African populations; hence, this cross-sectional study in a rural South African community examined allele and genotype frequencies, and their associations with cognitive function. Cognitive function was assessed using two different screening methods to produce a total cognition score and four domain-specific cognition scores for verbal episodic memory, executive function, language, and visuospatial ability. Cognitive phenotype and APOE genotype data were used to determine whether APOE variation was significantly associated with cognitive function in this population. Observed allele frequencies for 1776 participants from the HAALSI study [age 40–80years (mean=56.19); 58.2% female] were 58.1% (ε3), 25.4% (ε4) and 16.5% (ε2). Allele distributions were similar to the African super population, but different from all non-African super populations from the 1,000 Genomes Project. The ε3 homozygous genotype was most common (34.9%) and used as the base genotype for comparison in regression models. Four models were tested for each of the five cognitive phenotypes to explore association of APOE variation with cognitive function. In the first model assessing association with all genotypes for all individuals, marginally significant associations were observed for ε2 homozygotes where executive function scored higher by ~0.5 standard deviations (p=0.037, SE=0.23), and for ε3/ε4 heterozygotes where visuospatial ability scores were lower (p=0.046, SE=0.14). These did not survive correction for multiple testing. Regional African population differences were observed at the APOE locus. Marginally, significant associations between APOE genotype, and executive function and visuospatial ability indicate the need for larger studies to better examine these associations in African populations. Furthermore, longitudinal data could shed light on APOE genetic association with rate of change, or decline, in cognitive function

Polypharmacy and emergency readmission to hospital after critical illness:a population-level cohort study

From PubMed via Jisc Publications RouterPolypharmacy is common and closely linked to drug interactions. The impact of polypharmacy has not been previously quantified in survivors of critical illness who have reduced resilience to stressors. Our aim was to identify factors associated with preadmission polypharmacy and ascertain whether polypharmacy is an independent risk factor for emergency readmission to hospital after discharge from a critical illness. A population-wide cohort study consisting of patients admitted to all Scottish general ICUs between January 1, 2011 and December 31, 2013, whom survived their ICU stay. Patients were stratified by presence of preadmission polypharmacy, defined as being prescribed five or more regular medications. The primary outcome was emergency hospital readmission within 1 yr of discharge from index hospital stay. Of 23 844 ICU patients, 29.9% were identified with polypharmacy (n=7138). Factors associated with polypharmacy included female sex, increasing age, and social deprivation. Emergency 1-yr hospital readmission was significantly higher in the polypharmacy cohort (51.8% vs 35.8%, P<0.001). After confounder adjustment, patients with polypharmacy had a 22% higher hazard of emergency 1-yr readmission (adjusted hazard ratio 1.22, 95% confidence interval 1.16-1.28, P<0.001). On a linear scale of polypharmacy each additional prescription conferred a 3% increase in hazard of emergency readmission by 1 yr (adjusted hazard ratio 1.03, 95% confidence interval 1.02-1.03, P<0.001). This national cohort study of ICU survivors demonstrates that preadmission polypharmacy is an independent risk factor for emergency readmission. In an ever-growing era of polypharmacy, this risk factor may represent a substantial burden in the at-risk post-intensive care population.126pubpub

Association between Ophthalmic Timolol and Hospitalisation for Bradycardia

Introduction. Ophthalmic timolol, a topical nonselective beta-blocker, has the potential to be absorbed systemically which may cause adverse cardiovascular effects. This study was conducted to determine whether initiation of ophthalmic timolol was associated with an increased risk of hospitalisation for bradycardia. Materials and Methods. A self-controlled case-series study was undertaken in patients who were hospitalised for bradycardia and were exposed to timolol. Person-time after timolol initiation was partitioned into risk periods: 1–30 days, 31–180 days, and >180 days. A 30-day risk period prior to initiating timolol was also included. All remaining time was considered unexposed. Results. There were 6,373 patients with at least one hospitalisation for bradycardia during the study period; 267 were exposed to timolol. Risk of bradycardia was significantly increased in the 31–180 days after timolol initiation (incidence rate ratio (IRR) = 1.93; 95% confidence interval (CI) 1.00–1.87). No increased risk was observed in the first 30 days or beyond 180 days of continuous exposure (IRR = 1.40; 95% CI 0.87–2.26 and IRR = 1.21; 95% CI 0.64–2.31, resp.). Conclusion. Bradycardia is a potential adverse event following timolol initiation. Practitioners should consider patient history before choosing a glaucoma regime and closely monitor patients after treatment initiation with topical nonselective beta-blocker eye drops

Increasing lay-people’s intentions to initiate CPR in out of hospital cardiac arrest:Results of a mixed-methods ‘before and after’ pilot study of a behavioural text message intervention (BICeP)

BACKGROUND: Prompt, effective cardio-pulmonary resuscitation (CPR) increases survival in out-of-hospital cardiac arrest. However, CPR is often not provided, even by people with training. Low confidence, perceptions of risks and high emotion can prevent initiation of CPR. Behaviour-change techniques may be helpful in increasing CPR rates. AIM: To pilot a text-message behavioural intervention designed to increase intentions to initiate CPR, explore participant responses and pilot methods for future randomised controlled trial of effectiveness. METHODS: A ‘before and after’ pilot study plus qualitative interviews was undertaken. Participants were lay-people who had undertaken CPR training in previous 2 years. Participants were sent an intervention, comprising 35 text-messages containing 14 behaviour-change techniques, to their mobile phone over 4–6 weeks. Primary outcome: intentions to initiate CPR assessed in response to 4 different scenarios. Secondary outcomes: theory-based determinants of intention (attitudes, subjective norms, perceived behavioural control and self-efficacy) and self-rated competence. RESULTS: 20 participants (6 female, 14 male), aged 20–84 provided baseline data. 17 received the full suite of 35 text messages.15 provided follow-up data. Intentions to perform CPR in scenarios where CPR was indicated were high at baseline and increased (18.1 ± 3.2–19.5 ± 1.8/21) after the intervention, as did self-efficacy and self-rated competency. Self-efficacy, attitudes, perceived behavioural control and subjective norms were positively correlated with intentions. Qualitative data suggest the intervention was perceived as useful. Additional options for delivery format and pace were suggested. CONCLUSIONS: Pilot-testing suggests a text-message intervention delivered after CPR training is acceptable and may be helpful in increasing/maintaining intentions to perform CPR

Harbor and intra-city drivers of air pollution: findings from a land use regression model, Durban, South Africa

Multiple land use regression models (LUR) were developed for different air pollutants to characterize exposure, in the Durban metropolitan area, South Africa. Based on the European Study of Cohorts for Air Pollution Effects (ESCAPE) methodology, concentrations of particulate matter (PM; 10; and PM; 2.5; ), sulphur dioxide (SO; 2; ), and nitrogen dioxide (NO; 2; ) were measured over a 1-year period, at 41 sites, with Ogawa Badges and 21 sites with PM Monitors. Sampling was undertaken in two regions of the city of Durban, South Africa, one with high levels of heavy industry as well as a harbor, and the other small-scale business activity. Air pollution concentrations showed a clear seasonal trend with higher concentrations being measured during winter (25.8, 4.2, 50.4, and 20.9 µg/m; 3; for NO; 2; , SO; 2; , PM; 10; , and PM; 2.5; , respectively) as compared to summer (10.5, 2.8, 20.5, and 8.5 µg/m; 3; for NO; 2; , SO; 2; , PM; 10; , and PM; 2.5; , respectively). Furthermore, higher levels of NO; 2; and SO; 2; were measured in south Durban as compared to north Durban as these are industrial related pollutants, while higher levels of PM were measured in north Durban as compared to south Durban and can be attributed to either traffic or domestic fuel burning. The LUR NO; 2; models for annual, summer, and winter explained 56%, 41%, and 63% of the variance with elevation, traffic, population, and Harbor being identified as important predictors. The SO; 2; models were less robust with lower R; 2; annual (37%), summer (46%), and winter (46%) with industrial and traffic variables being important predictors. The R; 2; for PM; 10; models ranged from 52% to 80% while for PM; 2.5; models this range was 61-76% with traffic, elevation, population, and urban land use type emerging as predictor variables. While these results demonstrate the influence of industrial and traffic emissions on air pollution concentrations, our study highlighted the importance of a Harbor variable, which may serve as a proxy for NO; 2; concentrations suggesting the presence of not only ship emissions, but also other sources such as heavy duty motor vehicles associated with the port activities

Work-related stress:The impact of COVID-19 on critical care and redeployed nurses: A mixed-methods study

Lisa Salisbury - ORCID: 0000-0002-1400-3224 https://orcid.org/0000-0002-1400-3224Replaced AM with VoR 2021-07-08.Introduction: We need to understand the impact of COVID-19 on Critical Care (CCNs) and redeployed nurses and NHS organisations. Methods and analysis: This is a mixed methods study (QUANT – QUAL), underpinned by a theoretical model of occupational stress, the Job-Demand Resources Model (JD-R). Participants are critical care and redeployed nurses from Scottish and three large English units. Phase one is a cross-sectional survey in part replicating a pre-COVID-19 study and results will be compared with this data. Linear and logistic regression analysis will examine the relationship between antecedent, demographic, and professional variables on health impairment (burnout syndrome, mental health, posttraumatic stress symptoms), motivation (work engagement, commitment), and organisational outcomes (intention to remain in critical care nursing and quality of care). We will also assess the usefulness of a range of resources provided by the NHS and professional organisations. To allow in-depth exploration of individual experiences, phase two will be one-to-one semi-structured interviews with 25 CCNs and 10 redeployed nurses. The JD-R model will provide the initial coding framework to which the interview data will be mapped. The remaining content will be analysed inductively to identify and chart content that is not captured by the model. In this way the adequacy of the JD-R model is examined robustly and its expression in this context will be detailed. Ethics and dissemination: Ethics approval was granted from the University of Aberdeen CERB2020101993. We plan to disseminate findings at stakeholder events, publish in peer reviewed journals and at present at national and international conferences.https://doi.org/10.1136/bmjopen-2021-05132611pubpub

Communication and virtual visiting for families of patients in intensive care during the COVID-19 pandemic:A UK National Survey

© 2021 by the American Thoracic Society. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0.https://creativecommons.org/licenses/by-nc-nd/4.0/Rationale: Restriction or prohibition of family visiting intensive care units (ICUs) during the coronavirus disease (COVID-19) pandemic poses substantial barriers to communication and family- and patient-centered care. Objectives: To understand how communication among families, patients, and the ICU team was enabled during the pandemic. The secondary objectives were to understand strategies used to facilitate virtual visiting and associated benefits and barriers. Methods: A multicenter, cross-sectional, and self-administered electronic survey was sent (June 2020) to all 217 UK hospitals with at least one ICU. Results: The survey response rate was 54%; 117 of 217 hospitals (182 ICUs) responded. All hospitals imposed visiting restrictions, with visits not permitted under any circumstance in 16% of hospitals (28 ICUs); 63% (112 ICUs) of hospitals permitted family presence at the end of life. The responsibility for communicating with families shifted with decreased bedside nurse involvement. A dedicated ICU family-liaison team was established in 50% (106 ICUs) of hospitals. All but three hospitals instituted virtual visiting, although there was substantial heterogeneity in the videoconferencing platform used. Unconscious or sedated ICU patients were deemed ineligible for virtual visits in 23% of ICUs. Patients at the end of life were deemed ineligible for virtual visits in 7% of ICUs. Commonly reported benefits of virtual visiting were reducing patient psychological distress (78%), improving staff morale (68%), and reorientation of patients with delirium (47%). Common barriers to virtual visiting were related to insufficient staff time, rapid implementation of videoconferencing technology, and challenges associated with family members’ ability to use videoconferencing technology or access a device. Conclusions: Virtual visiting and dedicated communication teams were common COVID-19 pandemic innovations addressing the restrictions to family ICU visiting, and they resulted in valuable benefits in terms of patient recovery and staff morale. Enhancing access and developing a more consistent approach to family virtual ICU visits could improve the quality of care, both during and outside of pandemic conditions.Peer reviewedFinal Published versio