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Association between metabolic syndrome and physical fitness in firefighters: a protocol for a systematic review and meta-analysis
No full textIntroduction Among the emergency services, firefighters have the highest percentage of mortality (45%) due to sudden cardiac death, with the majority related to underlying cardiovascular disease. This necessitates that firefighters stay in good physical condition and maintain adequate cardiovascular fitness to cope with these stressors and perform their duties with minimal health risks. Therefore, this study aims to determine the association between metabolic syndrome and physical fitness in firefighters. Methods The authors will search the following electronic databases: PubMed/Medline, SCOPUS and Web of Science, with no limitations to publication year. For data extraction, the two principal reviewers will use a general data extraction form to retrieve the key characteristics of each study. The Rayyan intelligent systematic review tool will be used to screen and select studies for inclusion. Thereafter, information from the included studies will be captured on the researcher-generated data extraction form. The Joanna Briggs Institute (JBI) Critical Appraisal Tools for quantitative studies will be used to conduct the methodological assessment of each study included. Data will be analysed using Review Manager 5.3 to determine the exposure effects and MedCalc statistical software Ltd and will be used to determine the pooled correlation effects. The results will be presented using figures, graphs and tables. Ethics and dissemination Details for this systematic review protocol can be accessed on PROSPERO (CRD42024535088). The authors will disseminate this protocol and the findings of the systematic review and meta-analysis in peer-reviewed journals and in national and international conferences. In addition, this review will add significantly to the body of knowledge in the scientific community worldwide and assist academics in exploring research gaps on this topic
Square kilometre array science data challenge 3a: foreground removal for an EoR experiment
No full textWe present and analyse the results of the Science Data Challenge 3a (SDC3a, https://sdc3.skao.int/challenges/foregrounds), an epoch of reionization (EoR) foreground-removal exercise organized by the Square Kilometre Array Observatory (SKAO) on SKA simulated data. The challenge ran for 8 months, from 2023 March to October. Participants were provided with realistic simulations of SKA-Low data between 106 and 196 MHz, including foreground contamination from extragalactic and Galactic emission, instrumental, and systematic effects. They were asked to deliver cylindrical power spectra of the EoR signal, cleaned from all corruptions, and the corresponding confidence levels. Here, we describe the approaches taken by the 17 teams that completed the challenge, and we assess their performance using different metrics. The challenge results provide a positive outlook on the capabilities of current foreground-mitigation approaches to recover the faint EoR signal from SKA-Low observations. The median error committed in the EoR power spectrum recovery is below the true signal for seven teams, although in some cases, there are some significant outliers. The smallest residual overall is cMpc across all considered scales and frequencies. The estimation of confidence levels provided by the teams is overall less accurate, with the true error being typically underestimated, sometimes very significantly. The most accurate error bars account for per cent of the true errors committed. The challenge results provide a means for all teams to understand and improve their performance. This challenge indicates that the comparison between independent pipelines could be a powerful tool to assess residual biases and improve error estimation
Large quadrupole deformation in 20Ne challenges rotor model and modern theory
No full textThe spectroscopic quadrupole moment of the first excited state, QS (2+1 ), at 1.634 MeV in 20Ne was determined from sensitive reorientation-effect Coulomb-excitation measurements using a heavy target and safe energies well below the Coulomb barrier. Particle-γ coincidence measurements were collected at iThemba LABS with a digital data-acquisition system using the AFRODITE array coupled to an annular, doubled-sided silicon detector. A precise value of QS (2+1 ) = −0.22(2) eb was determined at backward angles in agreement with the only safe energy measurement prior to this work, QS (2+1 ) = −0.23(8) eb. This result adopts 1 ¯hω shell-model calculations of the nuclear dipole polarizability of the 2+1 state that contributes to the effective quadrupole interaction and determination of QS (2+1 ). It disagrees, however, with the ideal rotor model for axially symmetric nuclei by almost 3σ. Larger discrepancies are computed by modern state-of-the-art calculations performed in this and prior work, including ab initio shell model with chiral effective interactions and the multireference relativistic energy density functional (MR-EDF) model. The intrinsic nucleon density of the 2+1 state in 20Ne calculated with the MR-EDF model illustrates the presence of α clustering, which explains the largest discrepancy with the rotor model found in the nuclear chart and motivates the explicit inclusion of α clustering for full convergence of E2 collective properties
Nutritional and physiological demands shape the gut microbiome of female world tour cyclists
No full texthis cross-sectional study investigated whether elite female World Tour cyclists have a specific gut microbiome compared to non-athlete female controls, potentially resulting from the unique physiological and dietary demands of high-level endurance cycling. Fourteen female cyclists and thirteen matched controls provided fecal samples during a period of reduced training (off-season cycling). The samples were analyzed using 16S rRNA gene sequencing and short-chain fatty acid (SCFA) quantification. The results revealed significant differences in microbiome composition. The cyclists showed a higher abundance of Bacteroidota (72.7% vs. 15.3%) and a lower abundance of Firmicutes (22.1% vs. 62.5%) compared to the controls, along with reduced alpha-diversity (Shannon index, p < 0.05). Fiber-fermenting families such as Lachnospiraceae and Ruminococcaceae were depleted, consistent with a carbohydrate-focused and relatively low-fiber diet. Interestingly, fecal SCFA levels did not differ, suggesting functional adaptation of the microbiome. These findings indicate that the elite female cyclists may have developed a “performance-adapted” gut microbiome. However, due to the cross-sectional design, causality cannot be established, and the long-term health implications remain uncertain
Radio galaxies in Simba: a mightee comparison
No full textWe present a qualitative comparison between the host and black hole properties of radio galaxies in the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey with the radio galaxy population in the SIMBA suite of cosmological hydrodynamical simulations. The MIGHTEE data include a ∼1 deg2 pointing of the COSMOS field observed at 1.28 GHz with the MeerKAT radio telescope and cross-matched with multiwavelength counterparts to provide classifications of high- and low-excitation radio galaxies (HERGs and LERGs) along with their corresponding host properties. We compare the properties of the MIGHTEE HERGs and LERGs with that predicted by the SIMBA simulations where HERGs and LERGs are defined as radio galaxies dominated by cold or hot mode accretion, respectively. We consider stellar masses M∗, star formation rates SFR, AGN bolometric luminosity Lbol, and Eddington fraction fEdd, as a function of 1.4 GHz radio luminosity and redshift. In both MIGHTEE and SIMBA, the properties of HERGs and LERGs are similar across all properties apart from SFRs due to differences in host cold gas content in SIMBA. We predict a population of HERGs with low fEdd in SIMBA that are confirmed in the MIGHTEE observations and tied to the faint population at low z. The predictions from SIMBA with the MIGHTEE observations describe a regime where our understanding of the radio galaxy dichotomy breaks down, challenging our understanding of the role of AGN accretion and feedback in the faint population of radio galaxies
High dimensional beam inference ii: inference of a perturbed hera beam from simulated visibility data
No full textAccurate beam modelling is important in many radio astronomy applications. In this paper, we focus on beam modelling for 21-cm intensity mapping experiments using radio interferometers, though the techniques also apply to single dish experiments with small modifications. In 21-cm intensity mapping, beam models are usually determined from highly detailed electromagnetic simulations of the receiver system. However, these simulations are expensive, and therefore have limited ability to describe practical imperfections in the beam pattern. We present a fully analytic Bayesian inference framework to infer a beam pattern from the interferometric visibilities assuming a particular sky model and that the beam pattern for all elements is identical, allowing one to capture deviations from the ideal beam for relatively low computational cost. We represent the beam using a sparse Fourier-Bessel basis on a projection of the hemisphere to the unit disc, but the framework applies to any linear basis expansion of the primary beam. We test the framework on simulated visibilities from an unpolarized sky, ignoring mutual coupling of array elements. We successfully recover the simulated, perturbed power beam when the sky model is perfect. Briefly exploring sky model inaccuracies, we find that beam inferences are sensitive to them, so we suggest jointly modelling uncertainties in the sky and beam in related inference tasks
Sonic urbanism(s): listening to the city
No full textThis reflection on cultural geographies in practice draws upon experimental pedagogical practices from a Critical Urbanisms seminar entitled Sonic urbanisms: Sound, mobilities, culture and identity convened by the University of Basel and University of Cape Town. In the seminar we sought to explore the sonic aspects of Cape Town and its acoustic territories shaped through movements, circulations, and encounters. By experimenting with methods of listening to an African urban environment we offer insights to citiness developed through ‘sonic dérives’ – building on the concept from the Situationist International – that allowed our pedagogical process to drift with sounds: following, sampling, tracing. In this paper we seek to demonstrate firstly how our sonic dérives highlight emotional and affective relationships with urban space; and secondly, how our experiments shift us from hearing the city as a cognitive process of comprehension to listening as an active pedagogical and analytical process of speculation and imagination, straining towards possible meaning that is not immediately accessible. The outcomes of our sonic dérives illustrate how sound casts long spatial and temporal shadows, spreading across an acoustic territory without neat boundaries while also disrupting linear notions of past, present and future in the life of the African city through sonic connections to memories, desires and the formation of alliances. Through our experiments in sonic urbanism(s) the city is rendered in mobile acoustic territories that are fluid, ephemeral and intersecting as evidenced by a sonic map of Cape Town providing a multi-layered soundscape that is made visible and audible
Ritshidze's community-led monitoring system as a source of information on health system responsiveness in South Africa
No full textRitshidze is a large-scale community-led monitoring (CLM) system in South Africa, which has been conducting quarterly surveys of patient experiences at >400 primary healthcare facilities and community sites since 2019. This in-practice piece examines the data collected and publicly reported by Ritshidze, to highlight its role as an independent, complementary source of information on primary healthcare performance. It argues that CLM has significant potential to enhance health system responsiveness. We provide an overview of the data collection system, involving close to 500 data points organised into seven domains, and then focus on two sets of indicators that illustrate the utility of the monitoring and reporting system. The indicators selected are a set that assesses patient time spent at a facility (as a proxy for waiting times), illustrating both the depth and the breadth of the Ritshidze database; and the length of HIV prescriptions ('length of medicine refill'), as an indicator of the improvements in responsiveness of the health system to the needs of patients. Integrating CLM data into formal health system monitoring and evaluation frameworks could enhance the responsiveness of the health system to patients and communities, one of the key overall objectives of the district health system
Investigating teachers’ views to enhance parental academic support in poor school communities in the COVID-19 lockdown context in the Western Cape
No full textThe Lockdown schooling of the last two years shifted the educational discourse towards the role of parents in assisting learners at home with academic work. Schools across the globe expected parents to perform new academic support roles while learners were not in school, and the lack of a proper national program left parents unsatisfied with this important task. This study investigated how teachers understand the roles of parents in supporting learners with their academic programmes in poor school communities. These communities face different challenges and unique challenges. The purpose of the study is to investigate what the framework for parental academic support should look like and whether South Africa should move in the direction of a national academic support programme for parents to guide learners with academic work at home. The capability approach of Amartya Sen was used to focus on the freedoms and unfreedoms of teachers and parents in terms of academic support of learners at home. This study explores the education system, the progress thereof the role of parental academic support programmes, and teachers' views thereof. This study, therefore, encompasses theoretical and conceptual frameworks such as the Capability approach, whilst engaging analysis through a qualitative approach. A qualitative study guided the investigation in selected poor school communities in the Western Cape. Data was collected through semi structured interviews and focus group interviews. Confidentiality and ethical considerations were implemented to develop this research. This research identifies distance learning as a progressive way of teaching, which, during COVID-19 or lockdown schooling was the reality for teachers in the Western Cape and globally
Comparison of Goslon Yardstick and cephalometric analysis in nonsyndromic unilateral cleft lip and palate individuals in the Western Cape, South Africa
No full textObjective: To establish correlations between skeletal jaw relationship measured on lateral cephalograms and Goslon Yardstick scores for dental arch relationship (DAR) on orthodontic study models for unilateral cleft lip and palate (UCLP). Design: Retrospective review of consecutive cases. Setting: Multidisciplinary cleft and craniofacial clinics at two tertiary care centers in the Western Cape, South Africa. Patients: Forty-nine consecutive patients with nonsyndromic UCLP before they received orthodontic treatment and secondary alveolar bone graft (SABG). Interventions: Fourteen cephalometric angles measured by two observers and Goslon Yardstick scores determined by three observers. Inter- and intraobserver reliability determined using Cohen's Weighted Kappa statistic. Main Outcome Measures: Age, gender, and side of cleft were recorded. Cephalometric measurements and Goslon scores compared with regression analysis to determine correlations between angle ANB (cephalometric angle indicating anteroposterior relationship between the maxilla and mandible) and Goslon scores. Results: Mean age 10.7 years; 22 males and 27 females. Thirty-four (69.4%) of the clefts were left-sided. Kappa statistics ranged from good to very good for inter- and intraobserver reliability for cephalometric measurements and Goslon scores. No statistically significant differences between genders for cephalometric measurements and Goslon scores (P > .05). Mean ANB = 0.2(2.39) indicates Class III skeletal relationships for these individuals. Mean Goslon score 2.89. There was a moderate negative correlation of r = −0.5691 (P = 0) between ANB and Goslon score. Conclusion: Moderate negative correlation between ANB and Goslon Yardstick provides evidence that Goslon scores are valid and reliable indicators of skeletal jaw discrepancy for UCLP without the errors encountered using cephalometric radiographs