Global Challenges最新文献

We investigate the use of lemon CytroCell nanocellulose as a new biobased filler for Nafion-based proton exchange membranes. Pristine and composite membranes are prepared via casting and solvent evaporation technique. CytroCell is added up to 20 wt.% with respect to the polymer in a hydroalcoholic solution of Nafion perfluorosulfonic acid ionomer. Composite CytroCell@Nafion membranes are homogeneous on a molecular scale and showed enhanced proton conductivity with optimal performance for the composite membrane embedding 10 wt.% CytroCell. The composite membranes also showed improved flexibility and ductility compared to Nafion pristine membranes. Should stability of the new membranes be confirmed during prolonged PEM electrolyzer or H₂ fuel cell operation, these findings open the route to the development of enhanced PEM membranes of broad applicability.

Campylobacter jejuni is a widespread foodborne pathogen causing campylobacteriosis, a disease leading to diarrhea, fever, and gastroenteritis, able to adapt to many niches. Here, we present a hybrid in silico/in vitro study investigating the modulation of C. jejuni chorismate synthase by peptides. This enzyme belongs to the shikimate pathway, and it is an interesting target for selective growth modulation, being crucial for bacteria but not present in animals. To account for the identification of “natural” modulators, a library of 400 dipeptides is screened in silico through docking and molecular dynamics simulations to identify possible inhibiting sequences. The dipeptide glutamate-aspartate (ED) stood out, emulating the pharmacophoric fingerprint and interaction of the enzyme's natural substrate. Serendipitously, in vitro trials revealed ED as an activity enhancer. Considering the growth of C. jejuni in protein-rich matrices, this outlined a possibly relevant matrix-dependent effect worthy of dedicated investigations. The underpinning mechanisms are computationally investigated, describing possible ED-dependent effects on substrate/product turnover and enzyme structural stability. This study deepened the understanding of chorismate synthase and opened new directions in designing food-grade peptide-based modulators. This may provide ground to improve controlling bacterial growth in diverse contexts, including food safety and environmental/agricultural hygiene.

The main use of brush direct current (DC) motors has traditionally been in variable speed applications. Although the introduction of variable-frequency systems shifted the market toward alternating current (AC) technologies, direct current (DC) solutions remain relevant, especially with solar power generation where DC operation can avoid inverters. However, the high cost of brush DC motors limits broader use, creating a need for designs with higher efficiency, lower cost, and simplified manufacturing.A promising solution is the direct current motor with a winding-free rotor (DCFR). This design eliminates commutating poles and compensating windings while maintaining high overload capacity, and it doesn’t require expensive permanent magnets. Since all windings are stationary, the DCFR can operate with either a commutator or an electronic controller.Research results demonstrate clear advantages of the electronically controlled DCFR compared to a classic DC motor. With a rated power of 5.9 kilowatts and a nominal speed of 1490 revolutions per minute (rpm), the DCFR weighs only 60 kg versus 76 kg for the conventional design. Efficiency reaches 91.8%, compared to 85%. These improvements in efficiency, reduced weight, and lower material costs indicate that the DCFR design is highly suitable for both variable speed operations and solar energy applications.

The current perspective discusses the urgent need for the chemical industry to become more circular by adopting principles of circular economy. Importantly, many chemical products do not fit into the mainstream circular economy scheme that relies on a circular flow of resources, by recovering, retaining or adding to their value as many chemical products are intentionally dispersed into the environment. However, the chemical industry is a key sector that will support the return of the seven transgressed planetary boundaries to the safe operating space. Already defined circularity indicators – as published in the ISO 59000 family of standards – applicable to the chemical industry are discussed and new circularity indicators are introduced. In addition, the introduction of a waste framework with Scope 1, 2, 3 waste categories as a reporting tool is briefly discussed as an enhanced focus on waste generated along the value chain could improve the circular material use rate that currently is below 7%.

Only 8.6% of the global economy follows the principles of the circular economy. Mining and metal extraction processes generate over 90% of global waste, with slags being the major contributor to waste accumulation. Copper slags mostly consist of stable compounds that are safe for the environment, the main concern being the leaching of heavy metals into the ground. The market for using waste copper slags to produce value-added products is established in the last century and grown to an 800 million dollar market in 2024, with a predicted compound annual growth rate of 5.5% in the following years. However, only 15% of the generated copper slags worldwide are used for commercial purposes. In order to attain complete reusability of copper slags, industrial techniques must be adopted to eliminate threats from heavy metals and other possibly harmful elements. Additionally, it is essential to establish a market that can sustainably handle all quantities of generated slag. This review highlights the properties that make copper slags suitable for producing value-added products. With the rapid increase in population and urbanization, there is a potential to utilize copper slags for a-large-scale construction purposes such as earthworks and buildings. The demand for geotechnical applications and construction materials constantly increases and can absorb the entire quantity of copper slags generated. If this happens, it would mean an achievement of 100% reusability of copper slags in compliance with circular economy principles.

With One Health (OH) encompassing a holistic view of the interrelated health of humans, animals and environment, strategies based on OH approaches are gaining momentum in the prevention of emerging and re-emerging infectious diseases. OH is based upon the principles of intersectoral communication, cooperation and collaboration between stakeholders in the human health, animal health and environment sectors. In the face of changes induced by global threats such as climate change, biodiversity loss and urban encroachment into wildlife ecosystems, the environment sector plays an increasingly important role yet is underrepresented in OH operationalization often due to competing stakeholder priorities in animal and human health. Viewing OH through a systems thinking lens identifies the structures (components and relationships) and mental models (assumptions and beliefs) that show the need for stronger connections between OH stakeholders. In this viewpoint, the value of a systems thinking approach in OH that highlights a holistic approach to zoonotic disease prevention is discussed, and the need for interpersonal and intersectoral connections that precede communication and collaboration. In a changing world strengthening connections with the environment sector is now critically important for global pandemic preparedness and in building capacity for early identification of and response to zoonotic health risks.

The cover image is based on the article Aminated Lignin-Reinforced Biopolymer Hydrogels for Sustained Phosphate Delivery via Struvite Encapsulation in Acidic Environments by Collins Maurice etal., https://doi.org/10.1002/gch2.202500288.

RETRACTION: F. Asadzadeh and S. Pirsa, “Specific Removal of Nitrite from Lake Urmia Sediments by Biohydrogel Based on Isolated Soy Protein/Tragacanth/Mesoporous Silica Nanoparticles/Lycopene,” Global Challenges 4, no. 12 (2020): 2000061, https://doi.org/10.1002/gch2.202000061.

The above article, published online on 30 September 2020 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Mara Staffilani; and Wiley-VCH GmbH, Weinheim. The retraction has been agreed upon due to inconsistencies observed in the XRD spectra presented in Figure 5. Furthermore, it was identified that an image included in Figure 4 also appears in a previously published article by one of the authors. The authors explained that the XRD spectra in Figure 5 were obtained from an external XRD analysis centre, which was unable to provide the original data. They also explained that the duplication in Figure 4 was the result of an inadvertent copy-and-paste error during figure preparation and provided an alternative image. However, due to the unresolved concerns regarding the data, the editors no longer have confidence in the article's results and conclusions. The authors disagree with the retraction.

Evidence linking short-term exposure to air pollution, particularly PM_2.5, PM₁₀, NO₂, O₃, SO₂, and CO, with out-of-hospital cardiac arrest (OHCA) risk remains inconsistent. Large-scale studies using advanced air pollution exposure assessment techniques and spatiotemporal modeling are limited. This study investigates the association between short-term air pollution concentration, derived from satellite data, and OHCA events (2016 - 2019) in Lombardy, Italy, using a time-stratified case-crossover design. A two-stage distributed lag non-linear model, adjusted for meteorological factors, long-term trends, seasonality, intraweek patterns and holidays, is applied across 96 districts to estimate the exposure-lag-response relationship, followed by a regional meta-analysis. Subgroup analyses by age and sex of OHCA patients, with models stratified by urban-rural areas and seasons, and interaction with co-pollutants, are conducted. Among 37,613 OHCA cases, significant associations between OHCA and air pollutants are observed: NO₂ shows a delayed effect at lag 4 per 10 µg m⁻³ increase (RR: 1.071; 95%CI: 1.029–1.114), while PM_2.5 (RR: 1.029; 95%CI: 1.006–1.053), PM₁₀ (RR: 1.025; 95%CI: 1.005–1.046), and O₃ (RR: 1.009; 95%CI: 1.001–1.016) have immediate effects at lag 0 or lag 1. CO exhibits a modest association per 100 µg m⁻³ increase (RR: 1.007; 95%CI: 1.000–1.013, lag 4). Risks are elevated in summer months, and varied by urban-rural setting. No significant effect modification is detected across age or sex subgroups. Bi-pollutant models reveal notable interaction and confounding patterns.

The potential human health and environmental risks of micro- and nanoplastics (MNPs) have received increasing scientific attention in recent years. However, methodological challenges, particularly in hazard identification and exposure assessment, continue to hinder reliable risk characterization of MNPs. Taking into account the often complex composition of MNPs as a mixture of polymer, additives, and possible chemical and biological contaminants, comprehensive and robust assessments based on reproducible and harmonized protocols are needed before evidence-based regulatory decisions can be made. Furthermore, given the increasing amounts of plastics in various applications, it is already necessary to develop risk-mitigating strategies aimed at minimizing potential adverse effects on ecosystems and human health. To address 1) the need for better networking of research and standardization across the entire analytical workflow and 2) the requirements for risk-minimizing design and labeling of plastics, an expert workshop was held in the course of a Horizon 2020 research and innovation project, PlasticsFatE. The results of the event contain concrete recommendations, such as 1) a graduated approach to methodological unification with harmonization in particle and hazard analysis and standardization in monitoring, 2) a risk-minimizing design of plastics, and 3) the obligation to label toxic substances.