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Environmental interference and declining male fertility
Get PDFDeclining human male ‘fertility’ has been equated with a temporal decline in sperm counts, with reports collectively spanning the period between 1934 and 2018. Although sperm quality is impacted by adult male lifestyle choices, e.g. diet, stress and exposure to heat, environmental factors are thought to be central to this alarming observation. Since the decline in sperm counts reflects the outputs of meta-analytical studies, and thus the combination of data from different laboratories, statistical models have had to control for potential confounders, including differences in laboratory methodologies, changes in quality assurance standards, age, fertility group and exclusion criteria indicators. Sperm analyses arising from a population of stud dogs, where all analyses were carried out in a single laboratory, demonstrated a 30% decline in sperm motility over 26 years. Since these dogs resided in normal homes and were therefore exposed to the same household environment as human cohabitees, it has been postulated that the temporal decline in both dog and human sperm quality reflects environmental interference. This viewpoint article explores this contention and its implications for male ‘fertility’
Involvement of purinergic signalling in the vasomotor response to hypochlorous acid in porcine coronary artery
Get PDFHypochlorous acid (HOCl) is generated by neutrophils during the innate immune response. ATP is released from cells by various stimuli and during inflammation but whether ATP is released by and participates in the response to HOCl is unclear. This study investigated vasomotor effects of HOCl on the porcine coronary artery (PCA) and the involvement of ATP and purine receptors. HOCl at 100 μM induced rapid and transient endothelium-dependent relaxation followed by slow and sustained endothelium-independent relaxation. Transient endothelium-dependent relaxation was induced by 500 μM HOCl, followed by endothelium-dependent contraction, then slow endothelium-independent relaxation. 8-(p-sulphophenyl)theophylline (8-SPT), an adenosine/P1 receptor antagonist, blocked rapid relaxation and contraction to HOCl but an A 2A receptor antagonist, ZM 241385, and an A 1 receptor antagonist, DPCPX, had no effect. Suramin, a P2 receptor antagonist (and membrane channel inhibitor), blocked rapid relaxation (at 100 μM HOCl) and contraction to HOCl. Other antagonists for P2, P2X1, P2Y1 and P2X4 receptors (PPADS, reactive blue 2, NF449, MRS2179 and BX430) did not affect HOCl responses. Relaxation to exogenous ATP was inhibited by 8-SPT but not by suramin suggesting that suramin block of HOCl responses may involve inhibition of membrane channels and endogenous ATP release. Apyrase, which hydrolyzes nucleotides, abolished responses to HOCl, ATP and unexpectedly adenosine. Neither probenecid nor carbenoxelone (connexin and pannexin channel inhibi-tors) blocked responses to HOCl. Luminescent ATP assay showed that HOCl elicited ATP release from cultures of human coronary artery endothelial cells. These findings advance our understanding of inflammation by showing that HOCl evokes endothelium-dependent vasorelaxation and contraction in coronary arteries which may involve P1 receptors implicating endogenous adenosine, possibly generated from rapid metabolism of ATP released by HOCl
Personal Shapes of Sustainability Conduct and Organisational Management Control Systems
Get PDFPurpose Organisations including universities are under increasing pressure to demonstrate how they contribute to addressing the societal challenge of sustainability in the Anthropocene. This research offers insight into how university employees understand and discharge their sustainability conduct, in their work context, and within the framework of organisational management control systems. The paper highlights some of the challenges that arise at the point where employees and control systems intersect, and the sustainability conduct of employees that follows. Design/methodology/approach The research is a case study of a UK university, with primary qualitative data collected from 36 semi-structured interviews, in addition to secondary data from publicly available reports. Findings The research identifies how personal conduct and actions drive some of the unseen sustainability controls, that exist in an organisation. Additionally, the paper highlights some of the daily challenges when interacting with management control systems, faced by employees, in a university setting. Practical implications Employees are conscious about behaving in sustainable ways and conserving resources to minimise waste, but existing formal management control systems, are not consistently supporting optimum sustainability practices, decision-making and conduct
A Review of the Application of Ontologies and Semantic Web for Building Information Modelling and Digital Twins Based Construction Management
Get PDFAs the construction industry is moving towards digitalisation, the integration of advanced technologies like Building Information Modelling (BIM) and digital twins has become essential for enhancing project efficiency. Currently, the industry has the capacity to operate at BIM Maturity stage 2 but faces challenges in achieving seamless data integration and interoperability. Progressing toward BIM Maturity Stage 3 could benefit from adopting semantic web and linked data technologies, which enable a more structured, machine-readable data environment. However, the path to this level of integration remains complex. At the heart of the semantic web lies ontologies, playing a pivotal role in structuring domain knowledge. Therefore, through a systematic literature review, this study explores the integration of ontologies and semantic web technologies in BIM or Digital Twin environments for construction management. This study provides a trend and theoretical analysis under different construction management use cases to identify how ontologies and semantic web technologies have been utilised during the construction execution phase. The study identified eight different use cases, including safety management, compliance checking, and construction planning and production control, among others. The findings emphasise that while there is great potential in using ontologies and the semantic web for data integration, significant barriers remain, such as data privacy concerns, scalability issues, and the complexity of ontology mapping. These findings underscore the importance of addressing these challenges to fully harness the capabilities of semantic web technologies within BIM environments, providing a potential roadmap toward realising BIM Maturity Stage 3 and to enhance collaboration and data exchange in the construction industry. This study provides a roadmap for future research and technological development in applying semantic web technologies to advance construction management
Scour identification around offshore wind turbine monopile foundations using an unsupervised anomaly detection approach
Get PDFThis paper presents a novel data-driven framework for detecting scour damage around monopile foundations using acceleration data collected from an offshore wind turbine (OWT) tower under healthy conditions. The framework consists of multiple steps, including data generation, preprocessing, feature engineering, unsupervised Machine Learning (ML) model training, and performance evaluation. Validation is conducted against numerically-generated data using OpenFAST, with foundation stiffness modelled through a Soil-Structure Interaction (SSI) model developed in MATLAB. The healthy data are pre-processed and segmented prior to frequency-domain feature extraction. A One-Class Support Vector Machine Algorithm (OCSVM) is subsequently trained using features obtained through an unsupervised feature selection algorithm. The model performance is evaluated under real-time operational conditions expected offshore. Results indicate the framework's effectiveness in identifying scour states, particularly those exceeding a depth of 3 m for the given foundation analysed. The effectiveness of OCSVM for scour detection is appraised in terms of its potential for real-time condition monitoring of OWT foundations
Adoption Preferences of Greek Citizens in Stray Dogs: The Role of Morphological Characteristics
Get PDFA critical aspect of addressing the stray dog population issue in Greece involves the investigation of the likelihood of dog adoptions based on morphological traits. Recent statistics indicate that 43% of Greek households own at least one companion animal. This study aimed to explore some of the factors influencing the decision to adopt a stray and the morphological traits that are preferred by the adopters. To undertake this research, data spanning four years (2019-2022) were used; the data comprised information on 858 adoptions from a Greek animal welfare organization on the Island of Lesvos in the Aegean Sea. The analysis revealed that younger age, smaller size, and tan or tricolor coats were associated with faster adoption rates. In addition, when comparing the data of all four years (2019-2022), the year of adoption was found to be a statistically significant variable, which confirms that Greeks also followed the international trend of increased adoptions during the Covid-19 pandemic
Insights into environmental quenching at z ∼1: an enhancement of faint, low-mass passive galaxies in clusters
Get PDFUnderstanding the processes that transform star-forming galaxies into quiescent ones is key to unravelling the role of environment in galaxy evolution. We present measurements of the luminosity functions (LFs) and stellar mass functions (SMFs) of passive red-sequence galaxies in four galaxy clusters at 0 . 8 < z < 1 . 3, selected using deep Very Large Telescope (VLT) observations complemented with data from the Gemini CLuster Astrophysics Spectroscopic (GCLASS) and Gemini Observations of Galaxies in Rich Early ENvironments (GOGREEN) surv e ys. We find a significant enhancement in the abundance of faint/low-mass passive galaxies in both the LFs and SMFs of all four clusters compared to the field. This is further evidenced by a shallower low-mass slope in the composite passive cluster SMF, which yields a Schechter parameter α= -0 . 54 + 0 . 03 -0 . 03 , compared to α= 0 . 12 + 0 . 01 -0 . 01 for the field. Our findings indicate that quenching processes that act in clusters are enhanced compared to the field, suggesting that environmental quenching mechanisms may already be active by z ∼1. To reproduce the observed passive cluster SMF, we estimate that 25 ±5 per cent of the star-forming field population that falls into the cluster must have been quenched. Our results largely support traditional quenching models but highlight the need for deeper studies of larger cluster samples to better understand the role of environmental quenching in the distant Universe
A high-accuracy calibration-free spirometer based on Fiber Bragg Grating technique with neural network optimization
Get PDFChronic respiratory diseases as one of the major global health problems induce a high mortality rate. Increasing needs raised from domestic healthcare require the development of new spirometers with the combination of multiple features, e.g. low cost, light weight, high accuracy, easy to use, high reliability and long service life. Fiber Bragg Grating (FBG) technique outstands for spirometry due to its unique advantages. This study presents a novel FBG spirometer providing a high accuracy in vital capacity measurement (an average prediction error of 2.79 % for 37 volunteers), without the necessity of separate calibration of the system with the assistance of neural network. This FBG spirometer is easy to use and fast to analyze, moreover, it can be developed for more clinic and domestic applications like respiratory monitoring and the diagnosis of lung diseases based on the dynamic analysis of exhalation
Improving outcomes for people who are homeless and have severe mental illness in Ethiopia, Ghana and Kenya: overview of the HOPE programme
Get PDFAim HOPE (National Institute for Health and Care Research Global Health Research Group on Homelessness and Mental Health in Africa) aims to develop and evaluate interventions that address the unmet needs of people who are homeless and have severe mental illness (SMI) living in three African countries in ways that are rights-based, contextually grounded, scalable and sustainable. Methods We will work in the capital city (Addis Ababa) in Ethiopia, a regional city (Tamale) in Ghana, and the capital city (Nairobi) and a rural county (Makueni) in Kenya to understand different approaches to intervention needed across varied settings. We will be guided by the MRC/NIHR framework on complex interventions and implementation frameworks and emphasise co-production. Formative work will include synthesis of global evidence (systematic review, including grey literature, and a Delphi consensus exercise) on interventions and approaches to homelessness and SMI. We will map contexts; conduct focused ethnography to understand lived experiences of homelessness and SMI; carry out a cross-sectional survey of people who are homeless (n = 750 Ghana/Ethiopia; n = 350 Kenya) to estimate prevalence of SMI and identify prioritised needs; and conduct in-depth interviews and focus group discussions with key stakeholders to understand experiences, challenges and opportunities for intervention. This global and local evidence will feed into Theory of Change (ToC) workshops with stakeholders to establish agreement about valued primary outcomes, map pathways to impact and inform selection and implementation of interventions. Intervention packages to address prioritised needs will be co-produced, piloted and optimised for feasibility and acceptability using participatory action research. We will use rights-based approaches and focus on community-based care to ensure sustainability. Realist approaches will be employed to analyse how contextual variation affects mechanisms and outcomes to inform methods for a subsequent evaluation of larger scale implementation. Extensive capacity-strengthening activities will focus on equipping early career researchers and peer researchers. People with lived experience of SMI and policymakers are an integral part of the research team. Community engagement is supported by working closely with multisectoral Community Advisory Groups. Conclusions HOPE will develop evidence to support action to respond to the needs and preferences of people experiencing homelessness and SMI in diverse settings in Africa. We are creating a new partnership of researchers, policymakers, community members and people with lived experience of SMI and homelessness to enable African-led solutions. Key outputs will include contextually relevant practice and policy guidance that supports achievement of inclusive development
Effective emission control of aero-engines via nonlinear dual-estimators for uncertain states and parameters
Get PDFThis paper proposes an effective emission control strategy for an aero-engine using nonlinear dual-estimators, which aims to address challenges arising from state and parameter uncertainties. Transient air-fuel ratio (AFR) regulation issues, primarily caused by the wall-wetting and manifold-filling phenomena, are mitigated by a novel approach leveraging dual nonlinear estimators: (i) an extended Kalman filter (EKF) and (ii) an unknown dynamics estimator (UDE). The EKF estimates the fuel mass flow rate and unknown internal parameters, while the UDE compensates for nonlinear air-filling dynamics by estimating a lumped term involving the second derivative of air mass flow. The control framework is built upon a modified mean value engine model (MVEM), tailored to capture the unique dynamics of the rotary aero-engine. Building upon the foundational concepts developed in earlier research, this work moves toward practical application by demonstrating the proposed strategy through real-world experiments conducted on an AIE 225CS rotary aero-engine under a standard driving cycle, marking a significant step forward from theory to application. Furthermore, it introduces a complete stability analysis that addresses the coupling of dual-estimation errors, an aspect not explored in prior work. Comparative experimental results against an industry-standard gain-scheduling PID controller demonstrate the proposed method's performance in achieving improved AFR regulation and significant emissions reduction
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