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Enhancing essential oils: advanced extraction, sustainability, and nanotechnology for optimal use
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Main conclusion:
Our findings provide new insights into how integrating advanced extraction methods with nanotechnology enhances essential oil stability, bioavailability, and safety, offering significant potential for sustainable pharmaceutical, therapeutic, and environmental applications
Abstract:
Essential oils (EOs), volatile secondary metabolites extracted from plant parts such as leaves, seeds, and roots, are gaining prominence due to their broad therapeutic potential—including antifungal, antibacterial, anti-inflammatory, and antioxidant properties. Conventional extraction techniques like steam distillation and cold pressing typically yield 0.1–2.0% EO depending on plant species, part used, and method applied. However, EOs suffer from physicochemical limitations such as volatility, oxidative instability, and low bioavailability, which restrict their direct application in pharmaceutical and consumer products. Recent advances in nanotechnology—particularly nanoemulsions, liposomes, and polymeric nanoparticles—have demonstrated the ability to enhance EO bioavailability by up to 40%, prolong release times, and improve chemical stability under environmental stress. These encapsulation systems also reduce cytotoxicity and degradation while facilitating targeted delivery. This review critically evaluates modern EO extraction strategies, including green and sustainable approaches, and discusses nanoencapsulation technologies that optimize EO functionality. The emphasis focuses on safety considerations, physicochemical enhancements, and the translational potential of integrating EO-nanotechnology in medical and environmental applications.Abstract
Main conclusion:
Our findings provide new insights into how integrating advanced extraction methods with nanotechnology enhances essential oil stability, bioavailability, and safety, offering significant potential for sustainable pharmaceutical, therapeutic, and environmental applications
Abstract:
Essential oils (EOs), volatile secondary metabolites extracted from plant parts such as leaves, seeds, and roots, are gaining prominence due to their broad therapeutic potential—including antifungal, antibacterial, anti-inflammatory, and antioxidant properties. Conventional extraction techniques like steam distillation and cold pressing typically yield 0.1–2.0% EO depending on plant species, part used, and method applied. However, EOs suffer from physicochemical limitations such as volatility, oxidative instability, and low bioavailability, which restrict their direct application in pharmaceutical and consumer products. Recent advances in nanotechnology—particularly nanoemulsions, liposomes, and polymeric nanoparticles—have demonstrated the ability to enhance EO bioavailability by up to 40%, prolong release times, and improve chemical stability under environmental stress. These encapsulation systems also reduce cytotoxicity and degradation while facilitating targeted delivery. This review critically evaluates modern EO extraction strategies, including green and sustainable approaches, and discusses nanoencapsulation technologies that optimize EO functionality. The emphasis focuses on safety considerations, physicochemical enhancements, and the translational potential of integrating EO-nanotechnology in medical and environmental applications
Autonomic Microservice Management via Agentic AI and MAPE-K Integration
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While microservices are revolutionizing cloud computing by offering unparalleled scalability and independent deployment, their decentralized nature poses significant security and management challenges that can threaten system stability. We propose a framework based on MAPE-K, which leverages agentic AI, for autonomous anomaly detection and remediation to address the daunting task of highly distributed system management. Our framework offers practical, industry-ready solutions for maintaining robust and secure microservices. Practitioners and researchers can customize the framework to enhance system stability, reduce downtime, and monitor broader system quality attributes such as system performance level, resilience, security, and anomaly management, among others.Abstract
While microservices are revolutionizing cloud computing by offering unparalleled scalability and independent deployment, their decentralized nature poses significant security and management challenges that can threaten system stability. We propose a framework based on MAPE-K, which leverages agentic AI, for autonomous anomaly detection and remediation to address the daunting task of highly distributed system management. Our framework offers practical, industry-ready solutions for maintaining robust and secure microservices. Practitioners and researchers can customize the framework to enhance system stability, reduce downtime, and monitor broader system quality attributes such as system performance level, resilience, security, and anomaly management, among others
Regenerative tourism seeds in urban regeneration: Evidence from Milan, Italy
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Regenerative tourism represents an alternative to current urban tourism growth mode. Emerging regenerative tourism initiatives in cities encompass neighbourhood-level projects that aim at enhancing greater resident participation in the co-design of new visions of inner-city areas off-the-beaten track. Evidence indicates that the character of the neighbourhood can influence the desired tourism development and regenerative tourism trajectories in the area. Additionally, the degree of public participation and input can be decisive in the development and support of the new vision for the neighbourhood. Yet, the peril of regenerative tourism initiatives to trigger capital-driven gentrification and undermine the right to the city should not be underestimated. To this end, the following chapter sheds light on a neighbourhood-level initiative in Milan, Italy, a city that has been experiencing two housing crises over the last 20 years but has also gained prominence as prime international destination, including the hosting of the 2015 EXPO and of the forthcoming 2026 Winter Olympics. The findings show how initiatives led by residents bring the seeds of a regenerative urban tourism turn in a city where capital-driven gentrification and urban greenwashing represent the modus operandi of urban growth coalitions.Abstract
Regenerative tourism represents an alternative to current urban tourism growth mode. Emerging regenerative tourism initiatives in cities encompass neighbourhood-level projects that aim at enhancing greater resident participation in the co-design of new visions of inner-city areas off-the-beaten track. Evidence indicates that the character of the neighbourhood can influence the desired tourism development and regenerative tourism trajectories in the area. Additionally, the degree of public participation and input can be decisive in the development and support of the new vision for the neighbourhood. Yet, the peril of regenerative tourism initiatives to trigger capital-driven gentrification and undermine the right to the city should not be underestimated. To this end, the following chapter sheds light on a neighbourhood-level initiative in Milan, Italy, a city that has been experiencing two housing crises over the last 20 years but has also gained prominence as prime international destination, including the hosting of the 2015 EXPO and of the forthcoming 2026 Winter Olympics. The findings show how initiatives led by residents bring the seeds of a regenerative urban tourism turn in a city where capital-driven gentrification and urban greenwashing represent the modus operandi of urban growth coalitions
Intergroup Interaction and Attitudes to Migrants
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In a preregistered randomized experiment, we test the impact of interaction with migrants on host community members’ attitudes toward migrants. In three treatments, host community members were paired with a migrant from a nearby refugee camp to play an incentivized guessing game. The game was neutral in content in the first treatment, introduced cues to economic matters in the second, and introduced cues to identity in the third. A fourth treatment paired host community members with other hosts. In the control condition, hosts did not interact with anyone. The results show that interaction with a migrant significantly improved attitudes toward them compared to no interaction. Economic or identity cues did not diminish this effect. However, we see similar effects on attitudes to migrants in the treatment where hosts interacted with other hosts, suggesting that the effects are driven by human interaction in general, rather than by interacting specifically with a migrant.Abstract
In a preregistered randomized experiment, we test the impact of interaction with migrants on host community members’ attitudes toward migrants. In three treatments, host community members were paired with a migrant from a nearby refugee camp to play an incentivized guessing game. The game was neutral in content in the first treatment, introduced cues to economic matters in the second, and introduced cues to identity in the third. A fourth treatment paired host community members with other hosts. In the control condition, hosts did not interact with anyone. The results show that interaction with a migrant significantly improved attitudes toward them compared to no interaction. Economic or identity cues did not diminish this effect. However, we see similar effects on attitudes to migrants in the treatment where hosts interacted with other hosts, suggesting that the effects are driven by human interaction in general, rather than by interacting specifically with a migrant
The Chemistry of Halide-Based Solid Electrolytes: Unlocking Advances in Solid-State Li-Ion Batteries
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Solid-state batteries (SSBs) represent a transformative advancement in electrochemical energy storage, offering exceptional energy density, enhanced safety, and broad operational temperature ranges, making them ideal for next-generation applications. While liquid electrolytes dominate conventional lithium-ion batteries (LIBs) due to their high conductivity and efficient electrode interface wetting, their flammability and volatility pose significant safety risks, particularly in electric vehicles and portable electronics. Solid electrolytes, a cornerstone of SSB technology, offer a promising pathway to enhance LIB energy density and safety. Among the various inorganic solid electrolytes, halide-based materials have garnered the main attention due to their remarkable ionic conductivity and robust mechanical properties. This review highlights recent advances in halide solid electrolyte design, synthesis, and electrochemical performance. Additionally, it discusses the challenges facing their integration into SSBs, an innovative technology poised to drive societal progress in sustainable energy solutions.Abstract
Solid-state batteries (SSBs) represent a transformative advancement in electrochemical energy storage, offering exceptional energy density, enhanced safety, and broad operational temperature ranges, making them ideal for next-generation applications. While liquid electrolytes dominate conventional lithium-ion batteries (LIBs) due to their high conductivity and efficient electrode interface wetting, their flammability and volatility pose significant safety risks, particularly in electric vehicles and portable electronics. Solid electrolytes, a cornerstone of SSB technology, offer a promising pathway to enhance LIB energy density and safety. Among the various inorganic solid electrolytes, halide-based materials have garnered the main attention due to their remarkable ionic conductivity and robust mechanical properties. This review highlights recent advances in halide solid electrolyte design, synthesis, and electrochemical performance. Additionally, it discusses the challenges facing their integration into SSBs, an innovative technology poised to drive societal progress in sustainable energy solutions
Stabilizing Lattice Oxygen in Li-Rich Layered Cathodes by Boron-Doping Induced Anchoring Effect
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Li-rich Mn-based layered oxides (LRMLOs) have emerged as promising cathode candidates owing to their exceptional specific capacity (>300 mAh/g), high energy density (>1000 Wh/kg), and elevated operating voltages (>3.5 V vs Li+/Li). Nevertheless, the sluggish kinetics and poor reversibility of oxygen anion redox reactions fundamentally limit their practical implementation. Herein, we propose an interstitial boron doping strategy that precisely incorporates B atoms into the interstices between lithium and transition metal layers, creating robust BO4 coordination structures with enhanced B–O covalency. Multiscale characterization reveals that boron doping reduces oxygen Bader charges and increases oxygen vacancy formation energy, effectively suppressing the overoxidation of oxygen while stabilizing oxygen sublattices. Electrochemical evaluation demonstrates significantly improved cyclability with 63.6% capacity retention after 50 cycles at 0.05 C, a 19.3% enhancement compared to that of undoped counterparts. Density functional theory (DFT) calculations further verify that boron incorporation downshifts the O 2p-band center by 0.44 eV and reduces the average oxygen Bader charge, synergistically mitigating irreversible oxygen release. This atomic-level engineering approach establishes a viable pathway for achieving high activity yet stable oxygen redox in LRMLO cathodes.Abstract
Li-rich Mn-based layered oxides (LRMLOs) have emerged as promising cathode candidates owing to their exceptional specific capacity (>300 mAh/g), high energy density (>1000 Wh/kg), and elevated operating voltages (>3.5 V vs Li+/Li). Nevertheless, the sluggish kinetics and poor reversibility of oxygen anion redox reactions fundamentally limit their practical implementation. Herein, we propose an interstitial boron doping strategy that precisely incorporates B atoms into the interstices between lithium and transition metal layers, creating robust BO4 coordination structures with enhanced B–O covalency. Multiscale characterization reveals that boron doping reduces oxygen Bader charges and increases oxygen vacancy formation energy, effectively suppressing the overoxidation of oxygen while stabilizing oxygen sublattices. Electrochemical evaluation demonstrates significantly improved cyclability with 63.6% capacity retention after 50 cycles at 0.05 C, a 19.3% enhancement compared to that of undoped counterparts. Density functional theory (DFT) calculations further verify that boron incorporation downshifts the O 2p-band center by 0.44 eV and reduces the average oxygen Bader charge, synergistically mitigating irreversible oxygen release. This atomic-level engineering approach establishes a viable pathway for achieving high activity yet stable oxygen redox in LRMLO cathodes
Scalable synthesis of amorphous NiFe oxide hollow microspheres via glucose-mediated spray pyrolysis for industrial hydrogen production
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Developing high-performance, low-cost oxygen evolution reaction (OER) catalysts is crucial for advancing anion exchange membrane water electrolysis (AEMWE) in large-scale industrial green hydrogen production. Herein, We report a glucose-mediated spray pyrolysis method for synthesizing amorphous NiFe bimetal oxide hollow microspheres (A-NiFeOx) with controlled crystallinity, hierarchical porosity, and atomic-level compositional uniformity. Glucose acts as a dynamic template, guiding hollow structure formation through a self-limiting gas expansion mechanism and stabilizing the amorphous phase via kinetic trapping. The optimized A-NiFeOx-400 catalyst achieves ultralow overpotentials of 248 mV at 10 mA cm−2, 274 mV at 50 mA cm−2, and 288 mV at 100 mA cm−2, outperforming both its crystalline counterparts and commercial RuO2. Operando spectroscopic analysis confirms that A-NiFeOx-400 primarily follows the adsorbate evolution mechanism (AEM) under high current densities. Density functional theory (DFT) calculations show that structural amorphization induces localized charge redistribution around Fe centers, lowering the OER energy barrier by 0.72 eV through enhanced *OOH adsorption. In practical AEMWE systems, A-NiFeOx-400 achieves an unprecedented industrial current density of 10 A cm−2 at 3.56 V, while maintaining remarkable stability with approximately 1.25% activity decay over 800 h operation at 1 A cm−2. This method is scalable across 11 transition metal oxides and produces over 10 grams in 4 hours. By integrating atomic-scale electronic engineering with industrial manufacturability, it establishes a model for designing next-generation electrocatalysts for gigawatt-scale hydrogen production.Abstract
Developing high-performance, low-cost oxygen evolution reaction (OER) catalysts is crucial for advancing anion exchange membrane water electrolysis (AEMWE) in large-scale industrial green hydrogen production. Herein, We report a glucose-mediated spray pyrolysis method for synthesizing amorphous NiFe bimetal oxide hollow microspheres (A-NiFeOx) with controlled crystallinity, hierarchical porosity, and atomic-level compositional uniformity. Glucose acts as a dynamic template, guiding hollow structure formation through a self-limiting gas expansion mechanism and stabilizing the amorphous phase via kinetic trapping. The optimized A-NiFeOx-400 catalyst achieves ultralow overpotentials of 248 mV at 10 mA cm−2, 274 mV at 50 mA cm−2, and 288 mV at 100 mA cm−2, outperforming both its crystalline counterparts and commercial RuO2. Operando spectroscopic analysis confirms that A-NiFeOx-400 primarily follows the adsorbate evolution mechanism (AEM) under high current densities. Density functional theory (DFT) calculations show that structural amorphization induces localized charge redistribution around Fe centers, lowering the OER energy barrier by 0.72 eV through enhanced *OOH adsorption. In practical AEMWE systems, A-NiFeOx-400 achieves an unprecedented industrial current density of 10 A cm−2 at 3.56 V, while maintaining remarkable stability with approximately 1.25% activity decay over 800 h operation at 1 A cm−2. This method is scalable across 11 transition metal oxides and produces over 10 grams in 4 hours. By integrating atomic-scale electronic engineering with industrial manufacturability, it establishes a model for designing next-generation electrocatalysts for gigawatt-scale hydrogen production
Reclamation of boron from solid and liquid streams for fertilizer application
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Boron (B) is a crucial element for efficient plant growth and development; therefore, B-based fertilisers have been employed in agricultural applications. The need for B-based fertilisers for agricultural uses is continuously increasing as a result of the world's growing population. It is expected that the global market for B-based fertiliser will grow by around 6.3 billion by 2032; hence, demand for B sources will also increase. In addition to being used in fertiliser, B is also employed in the production of neodymium iron B (NdFeB) permanent magnets. The demand for NdFeB magnets is also continuously increasing. Hence, it is of the utmost importance to reclaim B from secondary resources due to the rising demand for B in a wide variety of applications. This review study addresses the recovery of B from various waste streams. The main focus is on the recovery of B from spent NdFeB magnets, borax sludge, and liquid streams such as brine water, seawater, sewage, industrial wastewater, and agricultural effluents. Different technologies for B recovery are discussed, such as sorption, solvent extraction, membrane processes, precipitation, and hydrometallurgical methods. Solvent extraction has been found to be a very effective approach for reclaiming B from spent NdFeB magnet waste and from liquid streams with high B concentration (>1–2 g/L). Further, the application of B-based fertiliser in agriculture application is reviewed. Challenges associated with B recovery from waste streams and future perspectives are also highlighted in this review
Exploring Self-competition as a Viable Motivation to Promote Physical Activity
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Persuasive systems design encompasses a wide range of concepts that may help users be motivated to achieve the targeted goal or behavior change. This study evaluates contemporary applications that seek to promote physical activity and finds that, although there are different implementations of competition-related features, they are not designed for individuals motivated by self-competition, a type of competition that allows individuals to compete against themselves to beat their own personal best performance. Furthermore, it explores how the psychological construct of competitive orientation can be used as a basis for personalizing persuasive systems. The paper then conceptualizes the design features of a system that addresses and caters to the self-competitive orientation of a user.Abstract
Persuasive systems design encompasses a wide range of concepts that may help users be motivated to achieve the targeted goal or behavior change. This study evaluates contemporary applications that seek to promote physical activity and finds that, although there are different implementations of competition-related features, they are not designed for individuals motivated by self-competition, a type of competition that allows individuals to compete against themselves to beat their own personal best performance. Furthermore, it explores how the psychological construct of competitive orientation can be used as a basis for personalizing persuasive systems. The paper then conceptualizes the design features of a system that addresses and caters to the self-competitive orientation of a user
Facile synthesis of SiOx/C as high-performance anodes for lithium-ion batteries
No full textAbstract
Despite its high capacity (∼2615 mAh·g−1), silicon oxide (SiOx) suffers from low electrical conductivity and volume expansion during cycling, leading to capacity fading. In this work, a SiOx/C composite was synthesized by magnesium thermal reduction using co-assembled mesoporous SiO2 and graphitic carbon nitride (g-C3N4) as precursors. The SiOx/C composite displays a sheet-like nanostructure with highly dispersed SiOx. The presence of carbon enhances the conductivity and structural stability of the composite, leading to a low charge resistance (94.0 Ω), fast lithium diffusion (DLi+ = 5.15 × 10−14 cm2·s−1), and excellent cycling capability (863 mAh·g−1 after 160 cycles).Abstract
Despite its high capacity (∼2615 mAh·g−1), silicon oxide (SiOx) suffers from low electrical conductivity and volume expansion during cycling, leading to capacity fading. In this work, a SiOx/C composite was synthesized by magnesium thermal reduction using co-assembled mesoporous SiO2 and graphitic carbon nitride (g-C3N4) as precursors. The SiOx/C composite displays a sheet-like nanostructure with highly dispersed SiOx. The presence of carbon enhances the conductivity and structural stability of the composite, leading to a low charge resistance (94.0 Ω), fast lithium diffusion (DLi+ = 5.15 × 10−14 cm2·s−1), and excellent cycling capability (863 mAh·g−1 after 160 cycles)