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Estimation of tree height using radar remote sensing in urban settings: a preliminary result
No full textGreen infrastructure directly impacts our daily life and promotes the mitigation of climate change at large. Urban woodlands are one of the green infrastructures that need regular monitoring. Existing urban tree inventories and monitoring schemes are based on spatial sampling assessment techniques. Urban tree health monitoring using remote sensing techniques such as LiDAR is used for inventory but needs a regular revisit. However, radar remote sensing has the potential to investigate the estimation of tree height, an important parameter towards tree health monitoring. Here we use Digital Elevation Model (DEM) differential interference based on Synthetic Aperture Radar (SAR) satellite data. We use Sentinel-1 (C-band) data to estimate the three heights in urban setting. In addition, we use exiting LiDAR data to estimate the tree height and ground-based smartphone Augmented Reality (AR) based height estimation for comparison and validation purposes. The result can be integrated with the available forest database and contribute towards regular monitoring of green infrastructure. As a case study to demonstrate the methodology, we investigate sample trees in Ealing, one of the boroughs of London with good coverage of urban trees and woodlands
Internal decay inspection of tree trunks using 3D point cloud and reverse time migration of ground penetrating radar data
No full textThe tree trunk necrosis and collapses in urban environments have caused large amounts of damage that threaten human safety. Several non-destructive testing methods have been applied to monitor and detect decay inside the trunks. Ground penetrating radar (GPR) has gained recognition due to its high efficiency and high resolution. However, the irregular shape of the trunks and their complicated internal structures make it still challenging to interpret the GPR data. In this paper, a combined approach is proposed to image the inner structures inside the irregular-shape trunks. Firstly, a 3D point cloud technique and the Canny edge detection algorithm are applied to obtain the curved outline of the trunk and the corresponding coordinates of each GPR A-scan data. Then, back-propagation (BP) and reverse time migration (RTM) are applied to reconstruct an image of the trunk cross-section. Finally, a de-noising method based on the total variation regularization is applied to suppress artifacts in the migrated images. Numerical experiment results show that the RTM algorithm based on the zero-time imaging condition can image the inner structure of the tree cross-section more accurately than the BP algorithm at comparable computation costs. Two diseased tree trunks further verify the proposed approach with subsistent decay and cavities in the laboratory and the field, respectively. The decay and cavities are well-focused in the migrated images. A visual inspection validates the field experiment results after the tree trunk was sawed down. It is concluded that the proposed approach can be applied to the internal decay inspection of tree trunks with high efficiency
Encoding Ethics to Compute Value‑Aligned Norms
Get PDFNorms have been widely enacted in human and agent societies to regulate individuals’ actions. However, although legislators may have ethics in mind when establishing norms, moral values are only sometimes explicitly considered. This paper
advances the state of the art by providing a method for selecting the norms to
enact within a society that best aligns with the moral values of such a society. Our
approach to aligning norms and values is grounded in the ethics literature. Specifcally, from the literature’s study of the relations between norms, actions, and values, we formally defne how actions and values relate through the so-called value
judgment function and how norms and values relate through the so-called norm promotion function. We show that both functions provide the means to compute value
alignment for a set of norms. Moreover, we detail how to cast our decision-making
problem as an optimisation problem: fnding the norms that maximise value alignment. We also show how to solve our problem using of-the-shelf optimisation tools.
Finally, we illustrate our approach with a specifc case study on the European Value
Study
Building 360-degree VR video for AquaFlux and Epsilon research instruments
Get PDFThe Virtual Reality (VR) technology is being utilised immensely in recent years for the purposes of demonstration and illustration a variety of prototypes and products especially on the world wide web platform. AquaFlux and Epsilon are two advanced research instruments that were developed by a research group at London South Bank University for medical and cosmetic purposes. These two medical tools have now been marketed in more than 200 organisations globally. However, for users to master and understand comprehensively how these two devices operate they often do require an intensive on-site training which is time-consuming, costly and in some cases like the current era of COVID-19 it becomes essential to offer clients the option of remote learning whether they were nationally or internationally based. Thus, the design of a VR environment that can simulate and envision all features and functionalities of AquaFlux and Epsilon is one of the ultimate solutions. 360-degree VR videos are going to empower users with the required knowledge and provide a broad essential feeling of how AquaFlux and Epsilon instruments function
The distributional impact of the Sierra Leone conflict on household welfare
Get PDFThis study examines the impact of the Sierra Leone civil war on household expenditure inequal-ity. The paper exploits three rounds of household survey data for Sierra Leone in an attempt to estimate the impact of the conflict on the distribution of household welfare over both short-run and long-run periods. The empirical approach uses RIF measures based on the Gini index and also provides estimates of treatment effects at selected quantiles of the unconditional house-hold expenditure distribution. The key findings reveal that localities subject to a protracted period of occupation by rebel forces experienced a sharp reduction in household expenditure inequality in the immediate aftermath of the conflict with most of the contraction evident at the top end of the distribution
Morphometric measurements can improve prediction of progressive vertebral deformity following vertebral damage
Get PDFPurpose: A damaged vertebral body can exhibit accelerated ‘creep’ under constant load, leading to progressive vertebral deformity. However, the risk of this happening is not easy to predict in clinical practice. The present cadaveric study aimed to identify morphometric measurements in a damaged vertebral body that can predict a susceptibility to accelerated creep.
Methods: 27 vertebral trabeculae samples cored from five cadaveric spines (3 male, 2 female, aged 36 to 73 (mean 57) yrs) were mechanically tested to establish the relationship between bone damage and residual strain. Compression testing of 28 human spinal motion segments (three vertebrae and intervening soft tissues) dissected from 14 cadaveric spines (10 male, 4 female, aged 67 to 92 (mean 80) yrs) showed how the rate of creep of a damaged vertebral body increases with increasing “damage intensity” in its trabecular bone. Damage intensity was calculated from vertebral body residual strain following initial compressive overload using the relationship established in the compression test of trabecular bone samples.
Results: Calculations from trabecular bone samples showed a strong non-linear relationship between residual strain and trabecular bone damage intensity (R2 = 0.78, P < 0.001). In damaged vertebral bodies, damage intensity was then related to vertebral creep rate (R2 = 0.39, P = 0.001). This procedure enabled accelerated vertebral body creep to be predicted from morphological changes (residual strains) in the damaged vertebra.
Conclusion: These findings suggest that morphometric measurements obtained from fractured vertebrae can be used to quantify vertebral damage and hence to predict progressive vertebral deformity
The use of behaviour change theory for infection prevention and control practices in healthcare settings: a scoping review
Get PDFBackground
Infection prevention and control (IPC) practices performed by healthcare workers are key to the prevention and management of infections. Compliance with IPC practice is often low, they are therefore commonly the focus of improvement interventions. Designing interventions that are based on behaviour change theories may help to improve compliance to practice. The aim of this review is to synthesise the evidence on the application of behaviour change theories to interventions to improve IPC practice in healthcare settings.
Methods
A scoping review was conducted following the Joanna Briggs Institute (JBI) methodological framework. The theories of focus were the Theoretical Domains Framework (TDF), Capability, Opportunity, Motivation, Behaviour (COM-B) and Behaviour Change Wheel (BCW). Studies which applied these theories to any IPC practice were included.
Results
Eleven studies were identified which met the inclusion criteria. The IPC behaviours investigated were hand hygiene (7), antimicrobial stewardship (3), and MRSA screening (1). Nine studies explored barriers and facilitators to existing IPC practice; three used their findings to design a behaviour change intervention or tool. Domains of ‘beliefs about consequences’, ‘environmental context/resources’, and ‘social/professional role and identity’ were identified as key across all three IPC behaviours.
Discussion
This review has demonstrated the use of behavioural theories to understand determinants of behaviour related to IPC practice. Currently there are few published examples of interventions to improve IPC practice that have been underpinned by behavioural theory. Practitioners in IPC should consider the use of these methods to enhance the efficacy of strategies to change healthcare worker behaviour
Reduction in transfer of micro-organisms between patients and staff using short-sleeved gowns and hand/arm hygiene in intensive care during the COVID-19 pandemic: A simulation-based randomised trial.
Get PDFBackground
Current personal protective equipment (PPE) practices in UK intensive care units involve “sessional” use of long-sleeved gowns, risking nosocomial infection transmitted via gown sleeves. Data from the first wave of the COVID19 pandemic demonstrated that these changes in infection prevention and control protocols were associated with an increase in healthcare associated bloodstream infections. We therefore explored the use of a protocol using short-sleeved gowns with hand and arm hygiene to reduce this risk.
Methods
ICU staff were trained in wearing short-sleeved gowns and using a specific hand and arm washing technique between patients (experimental protocol). They then underwent simulation training, performing COVID-19 intubation and proning tasks using either experimental protocol or the standard (long-sleeved) control protocol. Fluorescent powder was used to simulate microbial contamination, detected using photographs under ultraviolet light. Teams were randomised to use control or experimental PPE first. During the simulation, staff were questioned on their feelings about personal safety, comfort and patient safety.
Results
Sixty-eight staff and 17 proning volunteers were studied. Experimental PPE completely prevented staff contamination during COVID-19 intubation, whereas this occurred in 30/67 staff wearing control PPE (p = .003, McNemar). Proning volunteers were contaminated by staff in 15/17 control sessions and in 1/17 with experimental PPE (p = .023 McNemar). Staff comfort was superior with experimental PPE (p< .001, Wilcoxon). Their personal safety perception was initially higher with control PPE, but changed towards neutrality during sessions (p < .001 start, 0.068 end). Their impressions of patient safety were initially similar (p = .87), but finished strongly in favour of experimental PPE (p < .001).
Conclusions
Short-sleeved gowns with hand and forearm cleansing appear superior to sessional long-sleeved gowns in preventing cross-contamination between staff and patients
Influential Papers that Shaped Paradigms and Changed Practice in Infection Prevention in the Last 60 Years: Then, Now, and Future Directions.
No full textPurpose of Review
Advancements in infection prevention reduce morbidity and mortality in hospitalized patients. We recognize the authors and publications with substantial impact on health care epidemiology and clinical practice in the last 60 years.
Recent Findings
Substantial advancements in infection prevention include hand hygiene monitoring and feedback, prevention of central line-associated bloodstream infections, the use of chlorhexidine patient bathing, transmission-based precautions and improved environmental cleaning. Advancements in technology, including whole genome sequencing and hand hygiene sensor badges, may improve infection prevention efforts. While improvements in study design are necessary in infection prevention to best guide practice, current nosocomial infection prevention efforts are generally a cost-effective investment for healthcare systems.
Summary
Advancements in healthcare epidemiology over the last 60 years improved patient outcomes in hospital settings. Future well-designed studies are required, with a focus on implementation science and evolving technologies, to better define effective infection prevention strategies
