Global Challenges最新文献

Global challenges such as energy scarcity and food security are intensified by a growing population and substantial post-harvest food losses, contributing to alarming hunger levels. Solar drying is recognized as an effective, high-quality, and sustainable method for food preservation, significantly aiding global food security. Dryers are essential in agriculture and the food industry for extending crop shelf life by removing moisture through thermal energy, with solar thermal energy being particularly suitable due to its environmental benefits and availability. This article reviews the classification of solar dryers, including direct (DSD), indirect (ISD), and hybrid (HSD) systems, examining key components like solar collectors, drying chambers, and auxiliary systems and the factors affecting their performance. The review highlights that the efficiency of solar dryers depends on dryer type, solar irradiation, drying duration, and operational conditions. Recent advancements to enhance solar dryers' energy efficiency include hybrid systems incorporating auxiliary heating sources (electric or biomass), solar-assisted heat pump dryers, surface modification techniques, and heat storage systems utilizing sensible and latent heat storage. Findings suggest that HSD with auxiliary units can achieve up to 54% efficiencies, while solar collectors can reach up to 81%, yielding better product quality than traditional ones.

Agriculture faces growing challenges from climate change, pest pressures, and market instability. Crop diversification offers a sustainable strategy to enhance resilience and reduce the risks of monoculture. This review examines crop diversification as a response to these challenges, with a focus on its applications in sustainable agriculture, risk management, and food security. Strategies such as spatial, temporal, genetic, and intercropping diversification enhance soil health, improve pest management, and boost resilience to climate variability. The review highlights key principles, including ecological resilience, risk distribution, and resource optimization. By adopting diverse crops, farmers can mitigate soil degradation, reduce pest outbreaks, and stabilize incomes. Successful case studies from various regions, such as integrated rice-fish farming and agroforestry, demonstrate how diversification can improve productivity and sustainability. However, challenges remain, such as knowledge gaps, market access issues, and policy limitations. The review concludes with recommendations for future research and policy interventions, stressing the need for tailored diversification strategies, better support systems, and further exploration of innovative practices. This overview underscores the potential of crop diversification to build resilient, sustainable agricultural systems while addressing global food security concerns.

Plastic production and waste are a growing menace that affects the soil, the marine environment, and the air in a cumulative manner. The demand for mineral and bioplastics from renewable and biodegradable materials has therefore increased in all relevant sectors. The use of currently available degradable plastics is, however, limited by their poor mechanical properties and high production costs. In addition, many of today's plastics undergo uncontrolled biodegradation processes that involve harsh or expensive conditions and which may last from months to years. Here, the advantages of using multi-arm polymers for the production of sustainable mineral plastics are presented. A 4-arm poly(acrylic acid) is synthesized via atom transfer radical polymerization and is reacted with divalent calcium ions to obtain semi-liquid hydrogel or degradable plastic when dried. The mechanical properties of the different phases are evaluated and compared with linear poly(acrylic acid) of the same molecular weight. The multi-arm approach yielded improved mechanical characteristics, including self-healing and biodegradation without compromising other typical hydrogel characteristics. This concept of synthesizing multi-arm polymers with improved characteristics from building blocks of traditionally linear structures may be applicable to other mineral and bioplastic materials including acrylates, polysaccharides, and DNA.

Scientists are constantly striving to develop improved methods for reducing or eliminating the discharge of harmful heavy metals into drinking water sources and the environment. In light of this, this study investigates the potential of utilizing a naturally available and sustainable bio-waste material, Sepia pharaonis cuttlebone Powder (SCP), as an exceptionally effective adsorbent for the adsorption of Ni (II), Pb (II), Cu (II), and Fe (II) ions. SCP is also characterized by Fourier-transform infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Xray diffraction (XRD), and Energy dispersive Xray (EDX) analysis. The results reveal that the highest absorption values for Ni (II), Cu (II), and Fe (II) ions are observed at pH 8, while Pb (II) ions exhibit the highest absorption at pH 4. The absorption percentage of the ions displays an increasing trend with the amount of SCP used, as well as with contact time and magnetizing SCP duration. Additionally, the addition of Fe₃O₄ to SCP significantly improves the absorption rate of the samples. Both Langmuir and Freundlich adsorption models are found to fit the experimental data well. Overall, SCP, with or without Fe₃O₄ nanoparticles, shows great promise for water remediation processes by effectively removing heavy metals.

Despite gender diversity being driven by institutional bodies, companies have been relatively slow to diversify. In this study, it is investigated that how Australian boards select new directors, and how those selection processes affect their recruitment of women. In-depth interviews are conducted of those with first-hand experience of board appointments, followed by the thematic analysis and the application of natural language processing techniques to identify emotions and sentiment associated with these themes. The findings indicate that boards are adopting a social rather than rational approach to board selection. They are using networks, recruitment agencies, skills matrices and pools which on the surface appear to broaden the diversity of board members. But if they are not actively seeking gender diversity these methods can still limit diversity. For women, the lack of progress and barriers of access are resulting in high intensity of negative emotions. A key contribution of the research is the intersection of social approaches to board appointment and social identity theory with the dynamics of gender. Boards need to prioritize diversity for it to be achieved. There is a need for more active methods of recruitment and expansion of the networks and pools where directors are traditionally sought. Institutions can drive change through increasing targets and requiring enhanced reporting.

Extreme temperature events such as heatwaves are becoming increasingly severe and frequent because of climate change, posing significant challenges to public health and energy infrastructure. This study explores the impacts of extreme temperature events leading to heat-/cold waves on public health and energy consumption in Kazakhstan from 1959 to 2021. The most striking trends in heatwave-related indices emerge in the western and southwestern regions. Conversely, despite heightened coldwave intensity, a decline is noted in their frequency and number. The impact of heatwaves on various health conditions, notably consistent and statistically significant rises in all-cause and cardiovascular mortalities, is observed. Shifts in energy demand are also unveiled with a noticeable spike in cooling-degree days and a reduction in heating-degree days. The mean total energy consumption stood at 552 kWh across the country with an average annual energy generation of ≈8.76 kWh. To gauge the environmental implications, the mean CO₂ emissions are estimated at 464 kg per kWh for both heating and cooling purposes. With climate change set to escalate heatwaves, the need for comprehensive health planning is underscored to mitigate their adverse health impacts. Furthermore, transitioning from fossil fuels to green energy sources is crucial to reduce the environmental footprint.

While nanofluids can contribute enormously to enhanced oil recovery (EOR) in the upstream sector, conventional nanofluids are produced using complex equipment and expertise, which is somewhat limiting. To address this issue, herein, the use of effervescent-tablet-based nanofluids for EOR is reported. Tablets are formed by mixing and consolidating multi-walled carbon nanotubes, surfactants, and effervescent agents. Both tablet-based and conventional nanofluids are produced and then characterized for their thermal conductivities and dispersion stabilities. Thirteen recovery scenarios are investigated using a core flooding system, and include the use of single conventional fluids, steam and hot water cycles, steam with effervescent-tablet-based nanofluids, and steam with conventional nanofluids. Conventional or effervescent-tablet-based nanofluids are revealed to double the amount of extracted oil compared with other methods used in the recovery process. Tablet- and conventional-nanofluid-based recovery cycles provide 42.70% and 42.56% recovered oil, respectively, whereas conventional fluids and their cycles only extract 16.10% and 17.76%, respectively. The concentration and stability of the dispersed nanomaterial significantly affect the amount, properties, and composition of the recovered oil. Employing nanofluids composed of highly concentrated effervescent agents results in more short-chain hydrocarbons, which indicates that effervescent-tablet-based nanofluids are promising for EOR use, particularly because no infrastructure modifications are required.

The cover image is based on the Article IoT-Based Hand Hygiene Compliance Monitoring System and Validation of Its Effectiveness in Hospital Environments by Ju-Yu Wu et al., https://doi.org/10.1002/gch2.202400124.

Sub-Saharan Africa's adoption of inorganic fertilizer lags behind other developing nations, creating limitations for small-holder cocoa producers. Using the Diffusion of Innovations (DOI) Theory, articles assessing inorganic fertilizer (non)adoption by cocoa producers in Sub-Saharan Africa are reviewed. Factors influencing adoption fell into two major categories: socioeconomic characteristics of the potential adopter and characteristics of the innovation itself. Farm income, access to credit, labor requirements, and fertilizer price/availability are especially influential. Future studies and outreach efforts to consider the interplay of many personal, agronomic, and technological factors when promoting fertilizer adoption in cocoa farming are encouraged.

Hepatocellular carcinoma (HCC) stands as the predominant form of primary liver cancer, characterized by a dismal prognosis. Therapeutic options for advanced HCC remain sparse, with efficacy significantly hampered by the emergence of drug resistance. In parallel with research into novel pharmacological agents, advances in drug delivery systems represent a promising avenue for overcoming resistance. Lipid nanoparticles (LNPs) have demonstrated considerable efficacy in the delivery of nucleic acid-based therapeutics and hold potential for broader applications in drug delivery. This review describes the development of LNPs tailored for HCC treatment and consolidates recent investigations using LNPs to target HCC.