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Abstract The absorption of single asymmetric hyperbolic metamaterial (AHM) slab and cascaded AHM slabs has been theoretically studied in this paper. The proposed AHM consists of Polymethyl methacrylate (PMMA) and silver sheet. The numerical results show that the absorption of the single AHM slab is very sensitive to the azimuth angle, and the average absorption over the azimuth angle is only 0.2. However, the absorption of the cascaded AHM slabs can reach 0.7 in all the azimuth angles, and the average absorption over the azimuth angle can reach 0.88. Compared with the average absorption of the single AHM slab, the average absorption of the cascaded AHM slabs increases threefold. Highlights • The absorption of asymmetric hyperbolic metamaterial (AHM) has been studied. • The average absorption over the azimuth angle can reach 0.88. • The absorption of the cascaded AHM slabs can reach 0.7 in all the azimuth angles. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative disease that affects millions of individuals worldwide. Despite its prevalence, the exact causes and mechanisms behind OA are still not fully understood, resulting in a lack of effective treatments to slow down or halt disease progression. Recent research has discovered that extracellular vesicles (EVs) present in the circulation of young mice have a remarkable ability to activate musculoskeletal stem cells in elderly mice. Conversely, EVs derived from elderly mice do not exhibit the same potential, indicating that EVs obtained from young individuals may hold promise to activate aging cells in degenerative tissue. However, it remains unknown whether EVs derived from young individuals can also address cartilage degeneration caused by aging. In this study, we first evaluated EVs derived from young human plasma (YEVs) and EVs derived from old human plasma (OEVs) in an in vitro experiment using chondrocytes. The results revealed that YEVs effectively stimulated chondrocyte proliferation and migration, while OEVs from old plasma did not exhibit a similar effect. Given that OA represents a more complex inflammatory microenvironment, we further determine whether the benefits of YEVs on chondrocytes can be maintained in this context. Our findings indicate that YEVs have the ability to positively regulate chondrocyte function and protect them against apoptosis induced by IL-1β and TNF-α in an in vitro OA model. Furthermore, we discovered that lyophilized EVs could be stored under mild conditions without any alterations in their physical characteristics. Considering the exceptional therapeutic effects and the wide availability of EVs from young plasma, they hold significant promise as a potential approach to activate chondrocytes and promote cartilage regeneration in early-stage OA. • Young human plasma-derived extracellular vesicles (EVs) activate chondrocytes. • Old human plasma-derived EVs do not exhibit a similar positive effect. • Young human plasma-derived EVs rescue chondrocytes in inflammatory environment. • Lyophilization does not alter the physical characteristics of EVs. [ABSTRACT FROM AUTHOR]

Understanding pesticide residue patterns in crops is important for ensuring human health. However, data on residue accumulation and distribution in cowpeas grown in the greenhouse and open field are lacking. Our results suggest that acetamiprid, chlorantraniliprole, cyromazine, and thiamethoxam residues in greenhouse cowpeas were 1.03–15.32 times higher than those in open field cowpeas. Moreover, repeated spraying contributed to the accumulation of pesticide residues in cowpeas. Clothianidin, a thiamethoxam metabolite, was detected at 1.04–86.00 μg/kg in cowpeas. Pesticide residues in old cowpeas were higher than those in tender cowpeas, and the lower half of the plants had higher pesticide residues than did the upper half. Moreover, pesticide residues differed between the upper and lower halves of the same cowpea pod. Chronic and acute dietary risk assessments indicated that the human health risk was within acceptable levels of cowpea consumption. Given their high residue levels and potential accumulation, pesticides in cowpeas should be continuously assessed. [Display omitted] • Pesticide residues in cowpeas in the greenhouse were higher than those in the open field. • Repeated spraying resulted in residue accumulation of pesticides in cowpeas. • Clothianidin, the metabolite of thiamethoxam, was detected in cowpeas. • Pesticide residues in different cowpea parts and types were different. • Human health risks were considered to be acceptable. [ABSTRACT FROM AUTHOR]

Abstract To preliminarily study the law of natural dissipation and the relation to human health of a new insecticide (afidopyropen), the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method and a UHPLC-MS/MS system were used to extract and detect the afidopyropen and its metabolite (M440I007) from cucumber and nectarine. The limits of quantitation (LOQs) of both target compounds in two matrixes were reduced to 0.0001 mg/kg. Dissipative dynamics experiments indicated that afidopyropen residue dissipation is more consistent with a two-compartment kinetic model than a first-order kinetic model whether in cucumber or nectarine. The half-lives were less than 1.1 and 2.0 days in the distribution phase and up to 9.9 and 27.7 days in the elimination phase in cucumber and nectarine, respectively. The correlation coefficients were 0.9620, 0.9391, and 0.9923 for cucumber and 0.9676 and 0.9985 for nectarine from different locations. M440I007 initially increased rapidly, reached a maximum at 2 days, and then decreased gradually over time. Finally, dietary risk assessment indicated that the mixed residues of afidopyropen and M440I007 at the recommended dosage would not cause health concerns in population. Graphical abstract Image 1 Highlights • The dissipation kinetics of afidopyropen during crops production were investigated. • The First-order kinetic model was replaced by two-compartment mode. • The dietary risks of raw food contained afidopyropen after harvest were assessed. • A lower LOQ of afidopyropen in cucumber and nectarine contrast with previous studies. [ABSTRACT FROM AUTHOR]

Persistent weed growing in herbicide-resistant maize and soybean fields is controlled increasingly by glyphosate (GLY) and glufosinate-ammonium (GLU). There is increasing concern that consumers may be exposed to herbicide residues. A Total of 224 samples involved supervised trials and market sampling were carried out. And the levels of GLY and GLU were determined in maize and soybean samples by UPLC−MS/MS method. The residues of GLY and GLU were at a low level in all samples and ranged from <0.04 to 0.29 mg/kg and <0.04 to 0.91 mg/kg, respectively. Deterministic and probabilistic models were used to assess the dietary risk, and the highest risk quotient (RQ) values of GLY and GLU were 2.24 × 10−4 and 3.27 × 10−2, respectively. The RQs of GLU are significantly higher than that of GLY. Risk assessment results showed that GLY and GLU residues should not pose serious health risks to Chinese consumers. [Display omitted] • Supervised trials and market sampling of glyphosate and glufosinate-ammonium were carried out. • Dietary risk assessments of were performed using deterministic and probabilistic models. • The risk quotient of glufosinate-ammonium are significantly higher than that of glyphosate. • It is necessary to pay more attention to the use of glufosinate-ammonium in maize and soybean. • Residues of glyphosate and glufosinate-ammonium should not cause significant health risks. [ABSTRACT FROM AUTHOR]