Curtin University, Malaysia

Petrographic, mineralogical and geochemical analyses and 803 published detrital zircon U-Pb ages are here integrated to provide the first quantitative provenance analysis of the Oligocene-Miocene Nyalau Formation in the Sarawak Basin foreland basin, northwest Borneo. Statistical unmixing reveals that simple two-source models are insufficient: three distinct sources contributed sediment-the Malay-Thai Peninsula (58%), the Rajang fold-thrust belt (31%) and a previously unrecognised component (11%) characterised by syn-depositional Oligocene-Miocene volcanic zircons and Neoproterozoic populations absent from the other two established sources. This third source represents contemporaneous magmatic input plus recycled cratonic material from unexposed Bornean basement. Long-distance axial drainage from the Malay-Thai Peninsula dominated over proximal orogenic input from the Rajang fold-thrust belt. Compositional variations record coupled tectonic-climatic controls: quartz-rich intervals with high ZTR indices reflect extensive recycling coupled with prolonged weathering, whereas lithic-rich intervals indicate enhanced transverse input plausibly modulated by relative sea-level and monsoonal discharge variability. This quantitative three-source framework demonstrates that statistical provenance unmixing can reveal cryptic sediment contributors missed by binary mixing models, providing critical insights into tropical foreland basin evolution during major Oligocene-Miocene geodynamic reorganisation.

Aim: To trace the historical evolution of hospital nursing centrism in China (1835-present) and examine how institutional path dependence has shaped the subordinate status of nursing within a doctor-dominated healthcare system. Background/introduction: Despite major expansions in nursing education and policy advocacy, China's nursing profession remains structurally marginalized. Understanding the roots of this subordination requires a historical and institutional lens. Methods: Drawing on path dependence theory, this study analyzes five critical phases in the development of nursing in China from 1835 to the present. A four-dimensional analytical framework that encompasses professional, organizational, fiscal, and governance institutions was applied to archival records, policy documents, academic studies, and interview data. Results or findings: Findings reveal that nursing has been persistently embedded in a "doctor-led, nurse-subordinate" governance structure. Although educational and legislative reforms expanded nursing's professional scope, entrenched institutional arrangements across the four dimensions have locked nursing into a structurally dependent position. Discussion: The historical institutionalization of nursing as an auxiliary role has limited its professional identity, participation in governance, and access to resources. The analysis highlights the limitations of reforms focused solely on education and policy without restructuring governance mechanisms. Conclusion: The professional development of nursing in China has been constrained by enduring path-dependent forces. To achieve true professionalization, reforms must address deep-seated institutional logics. Implications for nursing and nursing policy: Professional empowerment requires the redesign of nursing roles, decision-making power, and career pathways within hospital governance. Policy reforms should dismantle hierarchical governance structures and institutionalize nurses' participation in leadership, ensuring equitable distribution of authority and resources.

The increasing reliance on fossil fuels for global energy production has intensified greenhouse gas emissions, highlighting the need for sustainable energy alternatives. Hydrogen is considered a promising green fuel due to its high energy density and conversion efficiency. Among various production pathways, microalgae-based biohydrogen generation via biophotolysis is particularly attractive owing to its high biomass productivity, adaptability to diverse water sources, flue gas mitigation potential, and low land requirements.This study investigates the effects of key microalgal growth parameters on biohydrogen production by Chlorella sp. through biophotolysis. The impacts of nitrogen purging during the transition from aerobic to anaerobic conditions, different photoperiod regimes (continuous illumination, continuous darkness, and a light–dark cycle), glucose supplementation (5, 10, and 15 g L⁻1), and temperature (25, 30, and 35 °C) were systematically evaluated. Microalgal cell density was monitored during hydrogen production to elucidate its relationship with hydrogen yield. Initial experiments were conducted in 10 mL test tubes to identify optimal conditions, which were subsequently applied to scale-up experiments in a 1000 mL jacketed reactor. Nitrogen purging significantly enhanced hydrogen production by removing oxygen and activating hydrogenase, resulting in a peak hydrogen concentration of 11 ppm. Continuous illumination yielded higher hydrogen levels than darkness and light–dark cycling. Glucose addition substantially increased hydrogen production, with the highest yield observed at 15 g L⁻1 (30 ppm). An optimal temperature of 30 °C also maximized hydrogen production. Under these conditions, hydrogen production increased as cell density decreased due to metabolic shifts. Scale-up experiments achieved a 405-fold increase in hydrogen yield, demonstrating the scalability potential of the process. These findings emphasize the importance of optimizing algal growth conditions to balance microalgal growth and biohydrogen production for future industrial applications.

The development of renewable energy sources is important in order to achieve the United Nations Sustainable Development Goals (SDGs). Waste cooking oil (WCO) is a promising feedstock for biodiesel production through transesterification. Heterogeneous bifunctional catalysts offer a sustainable alternative to conventional homogeneous bases such as NaOH and KOH. Among them, ferrimagnetic CaO-Fe3O4 provides dual acid-base functionality, enabling efficient catalysis with facile magnetic recovery and reuse. This study evaluated the environmental performance of biodiesel synthesis from WCO using homogeneous and heterogeneous catalysts through life cycle assessment (LCA), with biodiesel from virgin cooking oil (VCO) as a benchmark. A cradle-to-gate system boundary was applied, and 10 MJ of biodiesel was defined as the functional unit. Environmental impacts were assessed using midpoint and endpoint indicators. The results showed that electricity consumption was a notable contributor to overall emissions in systems employing heterogeneous catalysts. Sensitivity analysis of the CaO-Fe3O4-catalyzed WCO system showed that partial substitution of nonrenewable electricity with 50% renewable electricity reduced climate-change-related emissions by 35%. Overall, the results highlighted the environmental advantages of heterogeneous bifunctional catalysts for WCO biodiesel, particularly when integrated with renewable energy inputs.

Sound dampers are vital in modern weapon systems, particularly for military applications. Conventional silencers typically employ simple expansion chamber baffles, which have limitations in damping efficiency and production flexibility due to their metal construction. This study explores the application of the Tesla valve concept, which is traditionally used for fluid flow control, as an alternative gas suppression system for firearms. A 5.56 mm caliber firearm inner silencer was designed based on Tesla valve geometry using CAD and fabricated using the fused deposition modeling method with ABS-GF material. Experimental tests were conducted with five shots per design variation, measuring sound pressure level (SPL) and bullet velocity, while SPL data were analyzed using the signal-to-noise ratio (SNR) method. The two-partition Tesla valve design achieved the highest SPL reduction of 7.03 dB, although it decreased the bullet velocity by 63.38 m/s. This study demonstrates the feasibility of combining Tesla valve geometry with 3D-printed materials to create lightweight, efficient, and rapidly producible firearm silencers. These findings provide valuable insights for developers and manufacturers to explore alternative silencer designs and anticipate future trends in passive sound suppression technology.