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In order to develop sustained-release films with excellent performance, this study used polyvinyl alcohol (PVA) and chitosan (CS) as a film-forming substrate, β-cyclodextrin (β-CD) as a sustained-release agent, and oregano oil (OEO) as an antibacterial and antioxidant to prepare β-CD/CS/PVA composite films with different amounts of added OEO. The effects of addition of different amounts of OEO on the basic properties, physicochemical structure, antibacterial and antioxidant properties, and slow-release performance of the composite films were investigated. Fourier transform infrared (FTIR) spectroscopy indicated that none of the components altered the structure of the composite film. Increasing the content of OEO improved the ductility, hydrophobic properties, and light barrier properties, and also significantly increase the antibacterial and antioxidant capacities (P < 0.05). The diameters of inhibition zones of the composite film with 2% OEO against Staphylococcus aureus and Escherichia coli was 8.42 and 9.24 mm, respectively, and its DPPH radical scavenging rate was 80.84%. The composite film had excellent sustained-release performance in 95% ethanol, and the active substance in the composite films with 0.5% and 1.5% OEO could be released continuously for 540 min in this medium. It was concluded that the composite film with 2% OEOs had good overall performance, showing great potential for development.

Fresh milk with added hyaluronic acid (HA) was fermented by inoculating Streptococcus thermophilus and Lactobacillus bulgaricus. By measuring the pH, water holding capacity, viable bacteria count, rheological properties, volatile flavor substances, stability of yoghurt, the effects of HA with various molecular masses and various amounts of HA on the quality of yoghurt were evaluated. The results showed that various molecular masses of HA had different effects on the quality of yoghurt, but all could significantly improve its water holding capacity, smoothness and fineness (P < 0.05). The addition of high molecular mass (1 280 kDa) HA improved the elastic modulus (G’) and viscosity modulus (G”) of yoghurt, enhanced its stability index, promoted the growth and reproduction of L. bulgaricus and S. thermophilus, but caused obvious whey syneresis at the end of fermentation. Medium molecular mass (350 kDa) HA inhibited the growth and reproduction of L. bulgaricus, increased the pH, reduced the titratable acidity, and optimized the sensory quality of yoghurt. Low molecular mass (180 kDa) HA reduced the stability of yoghurt. To sum up, medium molecular mass HA can improve the quality of fermented milk.

By exploiting proximity coupling, we probe the spin state of the surface layers of CrI3, a van der Waals magnetic semiconductor, by measuring the induced magnetoresistance (MR) of Pt in Pt/CrI3 nano-devices. We fabricate the devices with clean and stable interfaces by placing freshly exfoliated CrI3 flake atop pre-patterned thin Pt strip and encapsulating the Pt/CrI3 heterostructure with hexagonal boron nitride (hBN) in a protected environment. In devices consisting of a wide range of CrI3 thicknesses (30-150 nm), we observe that an abrupt upward jump in Pt MR emerge at a 2 T magnetic field applied perpendicularly to the layers when the current density exceeds 2.5 × 1010 A m-2, followed by a gradual decrease over a range of 5 T. These distinct MR features suggest a spin-flop transition which reveals strong antiferromagnetic interlayer coupling in the surface layers of CrI3. We study the current dependence by holding the Pt/CrI3 sample at approximately the same temperature to exclude the joule heating effect, and find that the MR jump increases with the current density, indicating a spin current origin. This spin current effect provides a new route to control spin configurations in insulating antiferromagnets, which is potentially useful for spintronic applications.

The process of ryegrass combined with electrokinetics (REK) was developed to remediate the soil contaminated with Cd and Cu. The effects of voltage gradient, soil moisture content, and heavy metal concentration on the remediation efficiency of the process were investigated. Three voltage gradients (1.0, 2.0, 3.0 V/cm), three moisture contents (20%, 40%, 60%), and two heavy metal concentrations (Cd: 100 mg/kg, Cu: 150 mg/kg; Cd: 200 mg/kg, Cu: 300 mg/kg) were set. The ryegrass calculated for 5 d with uniform growth was selected, and directed-current (DC) was supplied and energized for 8 h/d for 5 d. The results showed that heavy metal ions migrated to the root system of ryegrass and the vicinity of the cathode under the action of an electric field, and were absorbed, degraded, and enriched to achieve the purpose of removal. The 3 factors had a significant impact on the remediation of REK. When the voltage gradient was 2.0 V/cm, the moisture content was 40%, and the concentration of heavy metals was low, the growth status of ryegrass was best. After remediation, the height of ryegrass increases by 4.4 cm, reaching a maximum of 13.5 cm. The fresh weight and dry weight of ryegrass were 0.68 g and 0.122 g. At this time, the removal rates of Cd and Cu in soil were 37.0% and 13.0%, respectively. It demonstrated that the application of ryegrass combined with electrokinetic technology in the remediation of heavy metal contaminated soil was promising. ENVIRONMENTAL IMPLICATION: Cu and Cd in soil are prone to migration and transformation, and can enter the human body through various pathways, posing a threat to human health. They are harmful substances. In this study, it involves the use of ryegrass combined with electrokinetics to remediate soil contaminated with Cd and Cu. Ryegrass will be beneficial for improving remediation efficiency, enabling electric remediation technology to enhance the removal efficiency of heavy metals in soil. The combination of electric remediation and plant biological action has broad application prospects in soil remediation. [ABSTRACT FROM AUTHOR]

Transport accessibility is an essential element in the planning of transport policies and plays a crucial role in territorial cohesion, but the role of transport accessibility for urban–rural integration has been rarely studied. This article explores the relationship between transport accessibility and urban–rural income gaps through the spatial error model, using the weighted average travel time (WATT) indicator and the Theil index of urban–rural income. The results show that transport accessibility has a U-shaped influence on the urban–rural income gaps within cities of China. As transport accessibility gradually improves, the urban–rural income gaps within cities tend to first narrow and then widen. Meanwhile, their relationship can show heterogeneity across regions, with improving transport accessibility and narrowing the urban–rural income gaps in the eastern and western cities, respectively. Such a result suggests that it is essential to reinforce transport links between western cities and other cities with high economic potential, which could improve transport accessibility and further narrow the urban–rural income gaps of western cities. For transport planning, policymakers should consider transport accessibility and its socio-economic impact on urban–rural integration. [ABSTRACT FROM AUTHOR]

Purpose: Comparing the outcomes of video-laryngoscopy and flexible fiberoptic bronchoscopy for endotracheal intubation in patients with cervical spine immobilization Methods: All of the comparative studies published in the PubMed, Cochrane Library, Medline, Web of Science, and EMBASE databases as of 8 Jan 2024 were included. All outcomes were analyzed using Review Manager 5.4. The primary outcomes were the successful first-attempt intubation rate, intubation time, heart rate after intubation, mean arterial pressure after intubation, overall intubation success rate, risk of tissue damage and sore throat. Results: The meta-analysis included six randomized controlled studies with a total of 694 patients. The outcomes of the meta-analysis revealed that the use of video laryngoscopy was better than flexible fiberoptic bronchoscopy in terms of the successful first-attempt intubation rate (P<0.05) and intubation time (P<0.05) in patients with cervical spine immobilization. However, there were no statistically significant differences in heart rate after intubation, mean arterial pressure after intubation, overall intubation success rate, risk of tissue damage, or sore throat (all P>0.05) between the video laryngoscopy and flexible fiberoptic bronchoscopy groups. Conclusions: Compared with flexible fiberoptic bronchoscopy, video laryngoscopy has superior tracheal intubation performance in terms of the first-attempt success rate and intubation speed. This finding was observed in patients with cervical spine immobilization who utilized a cervical collar to simulate a difficult airway. Additionally, both types of scopes demonstrated similar complication rates. Current evidence suggests that video laryngoscopy is better suited than flexible fiberoptic bronchoscopy for endotracheal intubation in patients immobilized with a cervical collar. Trial registration: Systematic review protocol: CRD42024499868. [ABSTRACT FROM AUTHOR]

Array pattern synthesis with low sidelobe levels is widely used in practice. An effective way to incorporate sensor patterns in the design procedure is to use numerical optimization methods. However, the dimension of the optimization variables is very high for large-scale arrays, leading to high computational complexity. Fortunately, sensor arrays used in practice usually have symmetric structures that can be utilized to accelerate the optimization algorithms. This paper studies a fast pattern synthesis method by using the symmetry of array geometry. In this method, the problem of amplitude weighting is formulated as a second-order cone programming (SOCP) problem, in which the dynamic range of the weighting coefficients can also be taken into account. Then, by utilizing the symmetric property of array geometry, the dimension of the optimization problem as well as the number of constraints can be reduced significantly. As a consequence, the computational efficiency is greatly improved. Numerical experiments show that, for a uniform rectangular array (URA) with 1024 sensors, the computational efficiency is improved by a factor of 158, while for a uniform hexagonal array (UHA) with 1261 sensors, the improvement factor is 284. [ABSTRACT FROM AUTHOR]

This contribution provides a thorough examination of the structural characteristics of pyrochlore-type lanthanide titanates and zirconates Ln2Ti2O7 and Ln2Zr2O7, across various length scales. This paper also examines their processing, interesting physical properties (electrical, magnetic, and thermal characteristics), and responses to high pressure and ion irradiation. Brief sections on the elemental oxides' crystal chemistry, pertinent phase diagrams, and energetics of defect formation are also provided. Pyrochlore-type Ln2Ti2O7 and Ln2Zr2O7 stand out as truly multifunctional materials. Moreover, they have emerged as fascinating materials due to magnetic geometrical frustration, arising from the ordering of magnetic Ln3+ and non-magnetic Ti4+ (or Zr4+) cations into separate, interpenetrating lattices of corner-sharing tetrahedra. This results in a diverse array of exotic magnetic ground states, such as spin-ice (e.g., Dy2Ti2O7 or Ho2Ti2O7) or quantum spin ice (e.g., Tb2Ti2O7), observed at both low and room temperatures. They also exhibit varied electrical and electrochemical characteristics. Some members such as Gd2Zr2O7, function as fast ion conductors with a conductivity (σ) of ≈10−2 S·cm−1 at 800 °C and activation energy (Ea) ranging from 0.85 to 1.52 eV, depending on the degree of structural disorder. Others, such as Gd2TiMoO7, are mixed ionic-electronic conductors with σ ≈ 25 S·cm−1 at 1000 °C, making them promising candidate materials for applications in energy conversion and storage devices and oxygen separation membranes. Their exceptionally low thermal conductivity (e.g., κ ∼ 1.1–1.7 W·m−1·K−1 between 700 and 1200 °C for Ln2Zr2O7), close to the glass-like lower limit of highly disordered solids, positions them as valuable materials for thermal barrier coatings. They can also effectively accommodate actinides (e.g., Pu, Np, Cm, Am) in solid solutions and sustain prolonged exposure to radiation due to alpha-decay events, while preserving the integrity of the periodic atomic structure. Proposed as major components in actinide-bearing ceramics, they contribute to the long-term immobilization and disposal of long-lived waste radionuclides from nuclear programs. Some of these properties are displayed simultaneously, opening avenues for new applications. Despite the wealth of data available in the literature, this review highlights the need for a better understanding of order/disorder processes in pyrochlore-type materials and the influence of the structural length scale on their physical and chemical properties. Recent experimental evidence has revealed that pyrochlore short-range structure is far more complex than originally thought. Moreover, pyrochlore local structure is now believed to include short-range, lower symmetry, ordered domains, such as the orthorhombic weberite-type of structure. Notably, short- and long-range structures appear decoupled across different length scales and temperature regimes, and these differences persist even in well-ordered samples. We believe that the pyrochlore structure offers a unique opportunity for examining the interplay between chemical composition, defect chemistry, and properties. [ABSTRACT FROM AUTHOR]