Publications by authors named "Wilks R"

Recent studies have suggested that high levels of social support can encourage better health behaviours and result in improved cardiovascular health. In this study we evaluated the association between social support and ideal cardiovascular health among urban Jamaicans. We conducted a cross-sectional study among urban residents in Jamaica's south-east health region.

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Introduction: Epidemiological transition to NCDs is a challenge for fragile health systems in the Caribbean. The Congregations Taking Action against NCDs (CONTACT) Study intervention proposes that trained health advocates (HAs) from places of worship (PoWs), supervised by nurses at nearby primary healthcare centres (PHCs), could facilitate access to primary care among vulnerable communities. Drawing on participatory and systems thinking, we explored the capacity of local PHCs in three Caribbean countries to support this intervention.

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In this study, we examine the surface-derived electronic and chemical structures of nanostructured GaRh alloys as a model system for supported catalytically active liquid metal solutions (SCALMS), a novel catalyst candidate for dehydrogenation reactions that are important for the petrochemical and hydrogen energy industry. It is reported that under ambient conditions, SCALMS tends to form a gallium oxide shell, which can be removed by an activation treatment at elevated temperatures and hydrogen flow to enhance the catalytic reactivity. We prepared a 7 at.

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tender X-ray absorption near-edge structure (XANES) spectroscopy at the P -edge was utilized to investigate the oxidation mechanism of aqueous HPO on Pt electrodes under various conditions relevant to high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) applications. XANES and electrochemical analysis were conducted under different tender X-ray irradiation doses, revealing that intense radiation induces the oxidation of aqueous HPO via HO yielding HPO and H. A broadly applicable experimental procedure was successfully developed to suppress these undesirable radiation-induced effects, enabling a more accurate determination of the aqueous HPO oxidation mechanism.

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Here, we report a detailed surface analysis of dry- and ambient air-annealed CsPbI films and their subsequent modified interfaces in perovskite solar cells. We revealed that annealing in ambient air does not adversely affect the optoelectronic properties of the semiconducting film; instead, ambient air-annealed samples undergo a surface modification, causing an enhancement of band bending, as determined by hard X-ray photoelectron spectroscopy measurements. We observe interface charge carrier dynamics changes, improving the charge carrier extraction in CsPbI perovskite solar cells.

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The oxidation of the aqueous HPO in contact with Pt was investigated for a fundamental understanding of the Pt/aqueous HPO interaction with the goal of providing a comprehensive basis for the further optimization of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Ion-exchange chromatography (IEC) experiments suggested that in ambient conditions, Pt catalyzes HPO oxidation to HPO with HO. X-ray photoelectron spectroscopy (XPS) on different substrates, including Au and Pt, previously treated in HPO solutions was conducted to determine the catalytic abilities of selected metals toward HPO oxidation.

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This study aimed to estimate dietary sodium and potassium consumption among Jamaicans and evaluate associations with sociodemographic and clinical characteristics. A cross-sectional study was conducted using data from the Jamaica Health and Lifestyle Survey 2016-2017. Participants were noninstitutionalized Jamaicans aged ≥15 years.

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Gallium is widely used in liquid metal catalyst fabrication, and its oxidized species is a well-known dielectric material. In the past decades, these two species have been well studied separately. However, the surface oxide layer-induced impact on the chemical and electronic structure of (liquid) gallium is still mostly unclear because of the extreme fast formation of thermodynamically stable surface GaO.

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Metal halide perovskites (MHPs) are semiconductors with promising application in optoelectronic devices, particularly, in solar cell technologies. The chemical and electronic properties of MHPs at the surface and interfaces with adjacent layers dictate charge transfer within stacked devices and ultimately the efficiency of the latter. X-ray photoelectron spectroscopy is a powerful tool to characterize these material properties.

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Background: Despite limited data on neighborhood factors and health risk in Caribbean populations, previous analyses from Jamaica have shown that neighborhood and home disorder were associated with lower physical activity and higher cumulative biological risk among women, while poorer neighborhood infrastructure was associated with higher overweight/obesity among men.

Design: Cross-sectional survey design.

Objectives: In this study, we explored whether community stressors, as measured by community violence, victimization and neighborhood disorder scores, were associated with cardiometabolic outcomes (obesity, diabetes, hypertension and high cholesterol) in urban Jamaican communities.

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Isolated active sites have great potential to be highly efficient and stable in heterogeneous catalysis, while enabling low costs due to the low transition metal content. Herein, we present results on the synthesis, first catalytic trials, and characterization of the GaRh phase and the hitherto not-studied GaRh phase. We used XRD and TEM for structural characterization, and with XPS, EDX we accessed the chemical composition and electronic structure of the intermetallic compounds.

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We correct values and figures for the resolution of the spectrometer, as proposed in [Opt. Express25, 31840 (2017)10.1364/OE.

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Decreased physical activity (PA) has been associated with residents living in neighborhoods perceived as being disordered or having high crime levels. What is unknown are the characteristics of individuals who engage in moderate to vigorous levels of PA (MVPA) despite living in these vulnerable neighborhoods, or who may be referred to as positive deviants (PD). We examined the factors associated with PD for PA among Jamaicans.

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The interface formation and chemical and electronic structure of the (Cd,Zn)S:Ga/CuSbS thin-film solar cell heterojunction were studied using hard X-ray photoelectron spectroscopy (HAXPES) of the bare absorber and a buffer/absorber sample set for which the buffer thickness was varied between 1 and 50 nm. We find a heavily intermixed interface, involving Cu, Zn, and Cd as well as significant Ga and Cu profiles in the buffer. The valence band (VB) offset at the buffer/absorber interface was derived as (-1.

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Healthcare relies upon the accurate and safe delivery of patient care. This is only achievable when systems are developed to ensure high quality, robust outcomes, for instance quality management systems. The concept of quality management can take on a different meaning depending on the context in which it is found.

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Article Synopsis
  • Combinatorial material science relies on effective, high-throughput techniques for material characterization, with X-ray photoelectron spectroscopy (XPS) offering detailed insights but traditionally known for being time-intensive.
  • Preliminary XPS data from a 72 × 72 cm Cu-Ni-O compositional library indicate that a simplified quantification approach allows for quicker evaluation of compositional ratios, while a more detailed analysis provides valuable chemical insights without significantly compromising speed.
  • The study suggests using faster techniques for real-time analysis during XPS, enabling quick identification of areas for further detailed studies, potentially making XPS a viable option for rapid characterization in combinatorial material science.
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  • CuInS grown under copper-rich conditions shows high optical quality but faces poor solar cell performance due to charge carrier recombination at the buffer/CuInS interface.
  • The study uses different spectroscopic techniques and electrical analysis to identify the interface recombination issues in Zn(O,S)/CuInS devices.
  • The findings suggest that while energy-level alignment isn't the main problem, defects near the interface are likely causing the performance-limiting recombination.
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Introduction: Optical three-dimensional scanning devices can produce geometrically accurate, high-resolution models of patients suitable for clinical use. This article describes the use of a metrology-grade structured light scanner for the design and production of radiotherapy medical devices and synthetic water-equivalent computer tomography images.

Methods: Following commissioning of the device by scanning objects of known properties, 173 scans were performed on 26 volunteers, with observations of subjects and operators collected.

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3D printing in modern radiotherapy allows users the ability to create custom devices which can be a valuable tool for use in brachytherapy source calibration. Radiotherapy centres may verify their brachytherapy source activity with a calibrated Farmer chamber. For this purpose, a jig was designed, 3D printed and commissioned for in-air source strength calibration.

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  • Tin is emerging as a safer alternative to lead in perovskite solar cells, but faces challenges due to its oxidation from Sn to Sn.
  • To tackle this issue, researchers are investigating the role of SnF in perovskite precursor solutions to prevent the formation of metallic Sn.
  • Analytical techniques reveal that fluoride ions preferentially bind to Sn, reducing Sn's inclusion in the perovskite structure and influencing the crystallization process of the material.
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There is evidence of an elevated risk of hypertension in populations that are primarily of African origin. Hypertension is predominantly asymptomatic, necessitating increased awareness. May Measurement Month was a descriptive, population-based, cross-sectional study of blood pressure (BP) screening and awareness campaign conducted in 2019 in a sample of 2550 participants (≥18 years) in Jamaica.

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The organic component (methylammonium) of CHNHPbICl-based perovskites shows electronic hybridization with the inorganic framework via H-bonding between N and I sites. Femtosecond dynamics induced by core excitation are shown to strongly influence the measured X-ray emission spectra and the resonant inelastic soft X-ray scattering of the organic components. The N core excitation leads to a greatly increased N-H bond length that modifies and strengthens the interaction with the inorganic framework compared to that in the ground state.

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Objective: To examine whether proximity and density of public open spaces, public parks, street connectivity, and serious and violent crimes were associated with Body Mass Index (BMI) and Waist Circumference (WC) within and across levels of urbanicity, sex and socioeconomic status (SES) in Jamaica, a small island developing state (SIDS).

Methods: Secondary analysis was conducted using data from the Jamaica Health and Lifestyle Survey 2008 (JHLS II). All respondents were geocoded to area of residence in Enumeration Districts (EDs).

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The limited long-term stability of metal halide perovskite-based solar cells is a bottleneck in their drive toward widespread commercial adaptation. The organic hole-transport materials (HTMs) have been implicated in the degradation, and metal oxide layers are proposed as alternatives. One of the most prominent metal oxide HTM in organic photovoltaics is MoO.

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