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Application of multiple scattering model towards investigating the reflection of wind turbine generated sound from rough ground
Full text linkThis work investigates the reflection of wind turbine generated sound from a rough ground represented by a distribution of semicylinders. Formulations for a multiple scattering model are developed by making some modifications to an existing multiple scattering theory. The modified multiple scattering model accounts for the angle of incidence outside the plane perpendicular to the semicylinder axes as well as the impedance of the ground plane. To account for the impedance of the semicylinders themselves, an impedance boundary condition is applied at their surfaces. Furthermore, in the context of the sound generated by wind turbines, where the source is often far from the receiver’s location, the incident wave is approximated as a plane wave. A study is carried out to compare predictions from the modified multiple scattering model to results from a boundary element method. The results between the modified model and the boundary element method agree satisfactorily. The results from the multiple scattering model alone have highlighted the significance of the orientation of a ground roughness on propagation. When the wind turbine sound propagates in the direction of the semicylinder axes, the rough ground effect is most like the flat ground equivalent. That is, the rough ground effect is at its smallest. The purpose of validating the modified multiple scattering model is to establish an efficient method for investigating the effect of a rough ground surface on the propagation of wind turbine noise
Zouave Theaters: Transnational Military Fashion and Performance by Carol E. Harrison and Thomas J. Brown (review)
No full textToward Mobile Neuroimaging: Design of a Multi-Modal EEG/fNIRS Instrument for Real-Time Use
Full text linkIn this study, we present the design and development of a mobile, multi-modal electroencephalography and functional near-infrared spectroscopy (EEG/fNIRS) device for wireless neurophysiological monitoring. The system was engineered to achieve high signal fidelity, low power consumption, and a fully untethered operation suitable for ambulatory brain research. The device integrates four Texas Instruments ADS1299 24-bit biopotential amplifiers, providing up to 32 simultaneous acquisition channels. Signal control, processing, and local storage via an SD card are managed by an STM32H7 microcontroller, while an ESP32-S2 module handles Wi-Fi communication. Dual-wavelength light-emitting diodes and OPT101 photodiodes form the optical front-end, driven by digitally controlled constant-current sources for stable illumination. The design employs galvanic isolation, multi-rail power management, and a four-layer PCB layout to minimise interference between analogue, power, and digital domains. Data are captured by a deterministic, clock-driven STM32 acquisition loop and forwarded to the ESP32, which operates under an RTOS and streams packets over Wi-Fi for collection on a mobile phone or PC using the Lab Streaming Layer (LSL) framework. The STM32H7 architecture was chosen for its capability to support future embedded edge-machine-learning functions, enabling on-device signal quality assessment and artefact rejection. Validation demonstrations include 32-channel synchronised acquisition using the ADS1299 internal test signal, eyes-open/eyes-closed alpha modulation visualised in EEGLAB, a forehead fNIRS breath-hold response with physiological spectral content, and real-time ECG/optical pulse streaming via LSL. The resulting system provides a compact platform with explicitly defined acquisition and data interfaces for synchronised EEG/fNIRS acquisition, enabling scalable, low-cost mobile neuroimaging research
Optical, Structural, and Electrical Properties of TeO2 – Na2O – NaX Glasses (X = Cl, Br, I): Roles of Crucible Materials and Halides
Full text linkAlkali tellurite glasses, which offer a broad glass-forming region along with large halide solubility, are excellent candidates as transparent conductive materials. TeO2 – Na2O – NaX (X = Cl, Br, I) glasses with halogen contents X ranging from 0 to 6 at. % (in total at. % of constituting elements Te, Na, O, and X) are investigated. Au crucibles alter their optical properties through the formation of inhomogeneously distributed gold nanoparticles. In contrast, alumina crucibles, despite undergoing a more severe dissolution, result in minor changes of the glasses’ structural and electrical properties. The electrical conductivity of such mixed anion glasses hinges on the mobility of the charge carriers (Na+ ions), and thus (i) on the bond strength of the Na-X bonds involved, as well as (ii) on the free volume within the glass network and consequently on the size of the anions. Accordingly, the electrical conductivity is found independent on the substitution rate for small halogens (X = Cl, Br), but increases up to threefold for large halogens (X = I)
Acute hypoglycemia attenuates serum matrix metalloproteinases and tissue inhibitors of metalloproteinases in type 2 diabetes
Full text linkBACKGROUND: Extracellular matrix (ECM) remodeling by matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) contributes to vascular complications in type 2 diabetes (T2D), but the impact of acute insulin-induced hypoglycemia on this axis is unclear. OBJECTIVE: Assess whether hypoglycemia alters circulating MMP/TIMP levels in T2D versus controls. METHODS: In a prospective study, 46 adults (23 T2D; 23 matched controls) underwent stepwise insulin to glucose ≤2.2mmol/L. Eleven MMPs and three TIMPs were measured at baseline, during hypoglycemia, and up to 24h post-recovery. RESULTS: At baseline, T2D had higher MMP1, MMP7, MMP9, and TIMP1/3. During hypoglycemia, controls showed a transient MMP1 rise with post-recovery decline. In T2D, MMP8 increased from 1-24h and exceeded controls at 1-4h. MMP2 fell early then rebounded at 4h. MMP3 rose at 4h in both groups and persisted to 24h in T2D. MMP9 remained elevated in T2D, decreasing only at 24h. TIMP3 declined during recovery in controls but stayed elevated in T2D; TIMP1/2 were unchanged. CONCLUSION: Acute hypoglycemia induces subtype-specific, time-dependent MMP-TIMP shifts. T2D shows amplified, prolonged responses-especially MMP8, MMP3, and MMP9-with insufficient TIMP buffering, suggesting a proteolytic milieu that may impair ECM integrity and vascular stability
The relationship between socially aversive personality of project managers and project performance: Evidence from the UAE
Full text linkWe study the relationship between socially aversive personality of project managers that influence behaviour, and project performance. Data from 409 project managers in the United Arab Emirates were collected using a 36-factor, workplace-focused dark personality questionnaire adapted from existing validated scales. Analysis was via Structural Equation Modelling (SPSS AMOS 29). Findings suggest that project managers: (i) exhibited higher Narcissism levels than Psychopathy or Machiavellianism; (ii) showed no significant variation in dark trait subscales by project characteristics; and (iii) display positively correlated dark trait subscales. Results also indicate: (iv) higher levels of each dark trait corresponding with a relationship to poorer project performance; and (v) Psychopathy’s independent effect not being statistically significant. Given their negative relationship with project outcomes, organizations should prioritize identifying and managing these traits. Given the paucity of studies relating to this research, our study was exploratory in nature. Thus, this study serves as a primer on project-focused dark personality research and offers a novel perspective on the antecedents of project performance
Participant observation in sport studies
No full textThis chapter provides readers with foundational knowledge and practical skills for conducting participant observation in sport studies. The chapter first introduces readers to participant observation, defining the method and highlighting its key strengths. The chapter then offers practical guidance for conducting participant observation in sport studies, addressing common challenges and providing strategies for success. This includes considerations for where and what to observe, the roles researchers may adopt and effective techniques for recording observational data. Following this, Thalia Holdom shares a researcher vignette, offering personal insights and lessons learnt from her experiences of conducting participant observation as a PG student. The chapter concludes with a set of critical and seminar questions designed to help readers develop their skills and reflect on their approach to participant observation
From science to storytelling: Advancing a climate knowledge–action framework through reflections on youth-focused, participatory action research in Vietnam
No full textClimate change presents urgent global challenges that demand swift and transformative responses. However, current efforts often fall short, revealing a crisis not only of environmental concern but also of social action. Responses to this have included climate change and sustainability education and communication, though these have tended to be knowledge-heavy, operating under outdated knowledge deficit-based assumptions that merely providing more information will drive action. Such responses and assumptions have also privileged scientific knowledge while overlooking diverse epistemologies and ways of knowing. This paper challenges these assumptions and puts forward a redefining of what it means to ‘know’ and ‘act’ on climate change. Within this, we propose integrating diverse knowledge systems, embracing both scientific and historically marginalised local knowledges, including indigenous, youth-led, experiential, emotional and affective perspectives. Importantly, we also propose a novel way to operationalise this democratically through utilising participatory action research and creative storytelling. Drawing upon our international collaboration with youth in three provinces along the Red River Catchment in northern Vietnam in 2022, a region facing significant climate challenges and injustices, we illustrate the potential of this research approach to bridge the knowledge–action gap. We conclude by introducing our holistic CLIMATE Knowledge Framework that encapsulates this pluralistic and democratic view of knowledge co-creation. This framework serves as a set of guiding principles for educators, researchers and policymakers to advance a more democratic, critically engaged, justice-framed and action-oriented paradigm, facilitating the envisioning and implementation of tangible solutions
Optimal dividend and scale of business strategies with reinsurance and premium pricing for insurance company
Full text linkThis paper investigates the optimal dividend and business scale strategies aimed at maximizing the value of an insurance company. While prior studies typically assume that insurers can only adjust their business scale through reinsurance, this study extends the framework by allowing the insurer to control the premium rate. Under more realistic market assumptions, we examine the joint optimization problem for two common types of reinsurance—proportional and excess-of-loss—across both arbitrage and non-arbitrage scenarios. We derive the optimal strategies for dividends and premium pricing, along with their corresponding value functions. The results show that the insurer should decrease the premium rate and reduce reinsurance coverage as the surplus increases. The optimal dividend policy follows a barrier strategy. Economic interpretations and numerical examples are provided to illustrate the findings
Critical approaches to Rights of Nature
No full textThe Rights of Nature (RoN) framework is often presented as a transformative legal paradigm that addresses the ecological crisis by recognising natural entities as legal subjects. However, this dominant narrative tends to oversimplify and universalise RoN, overlooking its diverse interpretations and applications. This article critically examines the theoretical and practical dimensions of RoN, questioning their assumed Indigenous roots, eco-centric nature, and decolonial potential. Through a comparative analysis of global legal experiences and a discussion of eco-centric versus non-centered approaches, the paper offers a more nuanced reading of RoN compared to recent scholarship - one that integrates Indigenous perspectives without reducing them to mere rhetorical justifications. Ultimately, it examines alternative frameworks grounded in ecological responsibility, the duty of care, and the concept of nonuse, proposing a critical pathway toward a more equitable and pluralistic approach to environmental governance