University of St Andrews Research Portal
Not a member yet
81329 research outputs found
Sort by
A laboratory-focussed desk review of health systems in Uganda, Kenya, and the UK to respond to current and future pandemics
No full textBackground Laboratory systems play a crucial role in managing diseases effectively, and the COVID-19 pandemic serves as a prime example. The pandemic underscored the need to make laboratory health systems more resilient and robust to respond to future pandemics.Methods We conducted a desk review guided by the six World Health Organization health system building blocks (health service delivery, health financing, medical products, vaccines, and technologies, human resources for health, governance, and health information systems).Results The three countries’ strengths include health information systems, well-established reference laboratories, mobile and community-level testing, a vibrant private laboratory sector in Uganda and Kenya, and a growing private sector in the UK. In Uganda and Kenya, there are laboratory connectivity solutions for molecular diagnostics, multi-disease testing platforms and specimen referral systems, while in the UK, there are hub-and-spoke networks. Weaknesses in Uganda and Kenya include vertical laboratory systems strengthening, ill-equipped laboratories, constrained and inequitable distribution of laboratory human resources, and limited data use. In the UK, there is chronic underfunding and undervaluing of disciplines supporting infection testing, microbiology and virology.Conclusions The growing contribution of the private sector in the three countries and the deployment of multi-disease testing platforms should be supported, given the advantage of shared financial costs in the face of chronic underfunding for laboratory systems
Non-invasive preservation assessment of archaeological animal bones by complementary imaging techniques
No full textThe preservation of archaeological bone is of great importance for both archaeological and conservation science studies. Traditional methods of preservation assessment, such as attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), are minimally invasive and destructive. Neutron and X-ray tomography offer a totally non-invasive novel analysis method for the state of preservation of archaeological bones. Seven archaeological animal bones were selected for analysis based on animal maturity, species, visual factors, and ATR-FTIR analysis results. Archaeological bone is a hierarchical composite material constructed from both organic and mineral components; therefore, neutron tomography and synchrotron X-ray tomography have been combined in this novel approach to assess the state of preservation of animal archaeological bone. The neutron data demonstrated that the organic distribution along the diaphysis of archaeological bones varied significantly both within bones and between different animal bones. There is minimal consistency between the samples, emphasizing the inhomogeneity in archaeological bone collections. X-ray tomography revealed unseen physical details, including cracks and substantial damage. The collection of this information via non-invasive methods is highly valuable for cultural heritage, providing a deeper understanding of the observed inhomogeneity in ATR-FTIR analysis data and revealing obscured physical details
Technology, labour, livestock, and the Maoist developmental state:four-wheeled tractors in China, 1953–1963
No full textFour-wheeled, 25–50 horsepower tractors imported to China from other socialist countries in the 1950s were a symbol of modernity and a source of problems. They were introduced to North China to increase multiple cropping. No significant increase in multiple cropping occurred in that region. The cost of tractor services far outweighed what could be earned with the labour they displaced in the 1950s and early 1960s. However, the government remained committed to them, even as it promoted cheaper five horsepower two-wheeled tractors. Greater use of four-wheeled tractors was sustained by the rapid downgrading of the hitherto privileged role of the tractor driver, alongside an ad hoc system of tacit subsidies. These changes meant deviation from the original vision for tractors. The dire fate of draught livestock during the era of rural collectivisation was an important reason for persevering with four-wheeled tractors even as the country turned away from Soviet development models
Donations to St Andrews, 1700-1900:methods and definitions
No full textThis working paper explains the ‘Methods’ and ‘Definitions’ underpinning ‘Section 3: Where did the University’s Money come from?’ of the final report on St Andrews and the Legacies of Empire (2024). The sections below formed the opening sections of a report on ‘Donations to St Andrews, 1700-1900’ presented to the Legacies of Empire steering group in September 2023 (which was itself an update on an internal report from December 2022)
Legacies of the ‘bridge man’: Catholic accompaniment, inter-class relations and the classification of surplus in Montevideo
No full textExponential asymptotics and higher-order Stokes phenomenon in singularly perturbed ODEs
No full textThe higher-order Stokes phenomenon can emerge in the asymptotic analysis of many problems governed by singular perturbations. Indeed, over the last two decades, the phenomenon has appeared in many physical applications, from acoustic and optical wave phenomena and gravity-capillary ripples to models of crystal growth and equatorial Kelvin waves. It emerges in a generic fashion in the exponential asymptotics of higher-order ordinary and partial differential equations. The intention of this work is to highlight its importance, and develop further practical methodologies for the study of higher-order Stokes phenomena, primarily for general nonintegrable problems. Our formal methodology is demonstrated through application to a second-order linear inhomogeneous ODE that exemplifies the simplest example of higher-order Stokes phenomena. In this model problem, the Borel transform can be derived explicitly, and this gives insight into the beyond-all-orders structure. We review and study additional examples, with physically important connections, including higher-order ODEs and eigenvalue problems
Thermodynamic growth of sea ice:assessing the role of salinity using a quasi-static modelling framework
No full textSea ice is a mushy layer, a porous material whose properties depend on the relative proportions of solid and liquid. The growth of sea ice is governed by heat transfer through the ice together with appropriate boundary conditions at the interfaces with the atmosphere and ocean. The salinity of sea ice has a major effect on its thermal properties so might naïvely be expected to have a major effect on its growth rate. However, previous studies observed a low sensitivity throughout the winter growth season. The goal of this study is to identify the controlling physical mechanisms that explain this observation. We develop a simplified quasi-static framework by applying a similarity transformation to the underlying heat equation and neglecting the explicit time dependence. We find three key processes controlling the sensitivity of growth rate to salinity. First, the trade-off between thermal conductivity and (latent) heat capacity leads to low sensitivity to salinity even at moderately high salinity and brine volume fraction. Second, the feedback on the temperature profile reduces the sensitivity relative to models that assume a linear profile, such as zero-layer Semtner models. Third, thicker ice has the opposite sensitivity of growth rate to salinity compared with thinner ice, sensitivities that counteract each other as the ice grows. Beyond its use in diagnosing these sensitivities, we show that the quasi-static approach offers a valuable sea-ice model of intermediate complexity between zero-layer Semtner models and full partial-differential-equation-based models such as Maykut–Untersteiner/Bitz–Lipscomb and mushy-layer models
Designing MetaHuman-based historical characters in virtual exhibitions and scenes:a case study on St Andrews
No full textThe convergence of digital heritage preservation and modern pedagogy informs the creation of historical characters in virtual settings. We proposed a workflow for creating lifelike, interactive characters that enhance the immersive learning experience, focusing on the medieval St Andrews scene as an illustrative case study. These characters, ranging from well-documented historical figures to generalized medieval citizens, are equipped with historically accurate garments and exhibit realistic expressions. The methodology provides a viable solution for educational and cultural institutions, offering a dynamic approach to experience and engage with history. Further, the paper provides an evaluation and discussion on the impact of these virtual characters in enhancing user engagement and learning experience. Our works underscore the transformative potential of VR in heritage preservation and education, paving the way for more dynamic, engaging, and accessible methods of historical education and cultural exploration
Engineering mechanical resonances of magnetoelectric transducers
No full textMagnetoelectric transducers are being investigated as a promising alternative for wireless power transfer in cases where small device size and/or low operation frequency are desired. To maximize the output power of such transducers, operation at their mechanical resonance frequency is imperative. However, a reduction in size along the direction of oscillation is intrinsically accompanied by an increase in resonance frequency. Here, we report on a computational shape optimization strategy to minimize the resonance frequency in magnetoelectric transducers by ≈38% within a set of given optimization constraints. We show that our algorithm can be used to guide the design of magnetoelectric transducers optimized to operate at different resonance frequencies and allows for consistent frequency spacing between transducers, thus enabling separately addressable devices and clustered operation. Finally, we propose four needle-shaped devices that could be used as bioimplants that impose minimal tissue damage upon direct insertion into tissue. The increase in resonance frequency associated with the needle shape is overcompensated by a frequency minimization step. Our work paves the way for computationally guided resonance frequency tuning in the field of magnetoelectric transducers