Global Challenges最新文献

The escalating global demand for food production, coupled with excessive fertilizer use and freshwater depletion, necessitates sustainable solutions in agriculture. The excessive utilization of fertilizers to enhance crop productivity reflects a variety of negative impacts, including environmental and economic challenges. In this study, a biodegradable, dual crosslinked hydrogel composed of polyvinyl alcohol (P), chitosan (Chi), and aminated lignin (AL) is developed to encapsulate struvite (MgNH₄PO₄·6H₂O), a slow-release phosphate fertilizer. AL is synthesized via Mannich reaction using polyethyleneimine to enhance nitrogen content and functionality. The structural and functional characterization of the hydrogels is carried out using FTIR, SEM, XRD, and TGA. All pristine formulations exhibit high water-holding capacity with non-Fickian swelling behavior, reaching swelling values up to 706 ± 20.7%. Upon struvite loading, the swelling capacities reduce significantly, reflecting enhanced matrix density and encapsulation efficiency. Phosphate release studies in acidic citric solution (pH 3.3) show sustained release over 6−7 days. Kinetic modeling confirms a super case II transport mechanism (n > 1) and dominant diffusion-controlled release (Higuchi model), while a poor fit to pseudo-first-order kinetics indicates nonconcentration-dependent behavior. This study highlights the potential of lignin-based hydrogels as eco-friendly platforms for nutrient-efficient fertilizer delivery, offering a promising pathway toward sustainable agriculture.

The impact of heat and heatwaves on human health constitutes a significant hazard, disproportionately affecting various regions worldwide and continuously exacerbating due to climate change. While human pathophysiology is well understood, addressing this challenge from a public-health perspective is essential to generate population-level insights and provide policymakers with evidence-based guidance. This calls for an interdisciplinary “environmental epidemiology” approach, which embraces multiple areas including (but not limited to) health sciences, geomatics, data-science, environmental analyses, and social sciences. Since the early 2000s, scientific production on this topic is increasing exponentially. This review aims to provide a narrative synthesis of the most relevant public-health studies, offering a comprehensive overview of prevailing perspectives within the scientific community. A key challenge highlighted is the lack of standardized thresholds, measures, and confounders, further complicated by variations in measurement methods, the urban heat island effect, and local disparities. The Distributed Lag Non-linear Model (DLNM) has emerged over the past decade as the gold-An standard for modeling heat-attributable health burdens. This approach enables risk stratification based on socio-demographic factors, evaluation of confounding variables, and scenario simulations. Numerous adaptation strategies are proposed, and with the support of emerging technologies, scientific research is increasingly shifting toward data-driven methodologies, unlocking new possibilities.

The management of risks in retired battery recycling chains remains a challenge, with a particular scarcity of dynamic models that can quantify risk loss and its impact on the co-evolution of stakeholders' strategies. To address this gap, a quantitative model integrating network calculus with conditional value-at-risk (CVaR) is proposed to quantify risk-induced loss. This study explores how varying risk parameters affect stakeholders' revenues, risk-induced loss, and their strategic behaviors. The results indicate that the impact of risk on government and recyclers differs based on their strategies, showing heightened sensitivity to risk under negative strategies. Moreover, the influence of risk parameters on risk-induced loss changes over time, with risk management capabilities peaking at a 64.1% contribution rate before declining. Government decision-making exhibits volatility in low-risk scenarios, leading to fluctuations in consumers' behaviors. Risks play a pivotal role in propelling sustainable development in the recycling market. While stakeholders initially lean toward negative strategies when risk-induced losses are minimal, escalating losses prompt a reassessment of such approaches, increasing the likelihood of transitioning to positive strategies. These findings provide valuable insights for enhancing risk management in power battery recycling.

Despite advances in Coronavirus Disease 2019 (COVID-19) prevention and treatment, emerging variants and persistent challenges continue to affect global health. Studies are retrieved from PubMed using title-based searches for COVID-19, SARS-CoV-2, and related therapies from 2020 to 2025, focusing on randomized controlled trials, systematic reviews, and clinical guidelines. This review explores treatments, nutrients, and adjuvant therapies that support the immune system in fighting COVID-19. It highlights the role of antiviral medications such as remdesivir, nirmatrelvir/ritonavir, and molnupiravir in reducing mortality and hospitalizations. Additionally, adjunctive therapies like corticosteroids, interleukin-6 (IL-6) inhibitors, Janus kinase (JAK) inhibitors, and N-acetylcysteine (NAC) are discussed for their potential to modulate inflammation. Nutritional support, including omega-3 fatty acids, vitamins D, C, and A, zinc, selenium, and probiotics, enhances immune function. Preventive measures, such as hygiene practices, wearing masks, and physical distancing, reduce transmission. An integrated approach that combines antiviral treatments with adjunctive therapies, prevention, and nutrition is crucial for improving outcomes.

This study investigates the influence of hydrogen (H₂) enrichment on the performance, combustion, and emission characteristics of a dual-fuel diesel engine operated with Mahua biodiesel/diesel blend (BDf20), in which H₂ is injected into the intake manifold at flow rates of 4, 6, 8, 10, and 12 L min⁻¹ under varying engine loads. As a result, the optimum engine performance is achieved at 10 L min⁻¹ H₂. At a peak load of 5.02 kW, BDf20 + H₂ (10 L min⁻¹) improves brake thermal efficiency (BTE) by 16.75%, and reduces brake specific fuel consumption (BSFC) by 10.83% compared to conventional diesel. For emission characteristics, unburnt hydrocarbons (HC), carbon monoxide (CO), and carbon dioxide (CO₂) decrease by 42.65, 44.74, and 20.91%, respectively, although NOx emissions increased by 17.1% due to higher combustion temperatures. Moreover, combustion characteristics show a 9.91% rise in peak in-cylinder pressure, a 20.82% increase in heat release rate, and an 8.26% longer ignition delay period. The results confirm the effectiveness of H₂ enrichment in improving combustion performance while significantly reducing pollutant emissions, showing that combining H₂ with biodiesel enhances the global Sustainable Development Goals (SDG) by advancing clean and renewable energy solutions.

High-nickel lithium-ion battery cathode materials are increasingly favored for their superior energy density but face challenges related to toxicity, cost, and critical material supply. This study assesses the current state of play in commercial cathodes, and presents a screening of the literature micro-dopants for LiNiO₂ (LNO), aiming to identify excellent electrochemical performance without compromising affordability or safety. Literature examples of tungsten, niobium, and zirconium doped cathode material all showed good performance, but are considered risky for further consideration due to the high costs and increased supply risk with these materials. A lithium excess sulfate doped material exhibited the best balance of sustainability and performance, delivering improved capacity retention and low raw material cost, with the only compromise of a very slightly elevated supply risk. The study highlights the trade-offs between performance metrics and sustainability considerations, offering a framework for more commercially viable cathode design.

Coal-fired power industry is a major carbon emitter which is responsible for global warming. The carbon market is an important tool to decarbonize the coal-fired power industry. This study extends the cited Chinese literature on how carbon net expenditures impact investments at the technology level. A metric, the long-term carbon net expenditure, is introduced to estimate the carbon net expenditure of decarbonization projects throughout their service life. The analysis suggests that retrofitting existing coal-fired power units for biomass co-firing will become economically feasible from 2043, and implementing carbon capture retrofitting will be viable from 2047. Enhancing the carbon market's long-term development path is essential to promoting these decarbonization efforts.

The finite supply of water on this planet led researchers to investigate nanocomposites, which are unique compounds with great performance and many applications. Many researchers are now interested in photocatalytic degradation methods due to their ability to facilitate both spontaneous and non-spontaneous reactions using light energy. The review's objective is to explain what nanocomposites mean, their types, various preparation procedures, and various characterisation approaches, and to employ nanocomposites in catalytic applications for wastewater treatment. It also seeks to compile some of the research on this topic. Through bibliometric analysis, the lineage and the extent to which countries are interested in publishing research on this issue in various methods of narration are illustrated. Nanocomposites can be used as catalysts to remove more than 90% of Cr (VI) after 120 min, phosphate (99.77%), ammonia (65.65%), Nitrite (99.98%) and remove several dyes such as Direct Blue 14 (94.57%), Congo Red (90.23%), Sunset Yellow (83.56%), brilliant cresol blue (BCB) (98.80%), neutral red (NR) (98.33%), methylene blue (MB) (99.6%) and more. Finally, challenges faced by nanocomposites in wastewater treatment are analyzed and summarized.

Air pollution poses a significant threat to global public health, with African megacities facing its severe consequences due to rapid urbanization, industrialization, and transportation challenges. In Africa, air pollution is responsible for 1.1 million deaths annually, with household air pollution accounting for two-third and ambient air pollution one-third of this burden. However, these percentages are likely to change in the near future due to the projected rapid urbanization and industrialization in the region. In the next 25 to 50 years African megacities are projected to grow rapidly and therefore experience a significant increase in air pollution-related health risks. Poor policy prioritization, limited monitoring infrastructure and conflicting interests and priorities further complicate the problem. In this paper, the key drivers of air pollution are discussed in African megacities, including urbanization, industrialization, transportation, and energy use. Further it is highlighted that there are significant challenges and barriers, as well as a pressing need for air quality monitoring, coordinated policies and effective air quality management to ensure sustainable development, mitigate the adverse health impacts of pollution and improve the quality of life across the continent.

This review thoroughly examines the potential of 2D transition metal borides (MBenes) for sophisticated energy storage applications. The investigation explores their structural stability, electrochemical characteristics, and a range of synthesis methods, including chemical and hydrothermal exfoliation procedures. Because of their strong mechanical characteristics, low diffusion energy barriers, and high theoretical capacities, MBenes perform better as anode materials for lithium-ion batteries (LIBs) than other 2D materials like MXenes. Functionalized MBenes also show adaptability in various applications, such as lithium–sulfur batteries and nitrogen reduction catalysis. Their actual application is hampered by issues including oxidation and surface imperfections, despite their encouraging qualities. This analysis demonstrates MBenes as a promising anode material for next-generation energy storage devices and highlights the necessity for more research into scalable, eco-friendly synthesis techniques for achieving sustainability.