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Polyvinyl alcohol (PVA) is well-known for its excellent mechanical properties and eco-friendliness in food packaging. Recently, PVA has gained significant attention in research due to its potential as antibacterial substrates. However, because of its high hydrophilicity, practical application of pure PVA film has been limited by low water resistance and rapid bacterial growth in humid conditions. Diverse effective strategies have been developed to decrease hydrophilicity and endow films with antibacterial properties. This review provides an overview of universal antibacterial agents and their functions in PVA-based packaging films. It also introduces the changes in the mechanical and physical properties of PVA-based films after adding antibacterial agents. Additionally, the release behavior of antibacterial agents in PVA-based film materials and their practical applications in the food industry is discussed in fresh food packaging. Biodegradability of PVA-based films is also mentioned, with a promising future for more effective and eco-friendly food packaging materials.

This paper proposes state space modeling and Kalman filtering as the theoretical foundation to explore the impact of China’s monetary policy on the offshore RMB market and capital flows. In the state space model, the relationship between observable and unobservable variables is established, with the Hidden Markov Model representing the state vector as a first-order Markov process to estimate unobservable variables. Additionally, a variable parameter state space model is proposed to alter the relationship between explanatory variables and the dependent variable. Kalman filtering, as the core of the state space model solution algorithm, calculates the likelihood function through prediction error decomposition to estimate unknown parameters. The optimal lag of the model is determined to be 2 after constructing the VAR model in the empirical analysis, and the first-order autoregressive model is used to calculate variable parameters. The elasticity coefficient of the depth of development of the offshore RMB market on capital flows is the most significant variable, with a value of 0.96. Following this, the RMB exchange rate has an elasticity coefficient of 0.78.

To evaluate the correlation between methylene tetrahydrofolate reductase (MTHFR) gene rs1801133 C>T polymorphisms and risk of osteoporosis.

In this report, PEDOT composite films were prepared by in situ electrochemical polymerization. 1-Ethyl-3-methylimidazole bis(trifluoromethylsulfonyl)imide (EMI-TFSI) was used as an ionic liquid dopant for PEDOT:PSS films. Subsequently, these PEDOT:PSS/EMI-TFSI films were compared with PEDOT:PSS films based on their morphology, structure, electrochromic properties, and optical properties at different deposition voltages and deposition times. It was observed that the addition of EMI-TFSI enhanced all the aforementioned properties of the films. PEDOT:PSS/EMI-TFSI films were seen to have a larger ion diffusion coefficient (1.38 × 10−20 cm2·s−1), a wider color change range (43.48%), a shorter response time (coloring response time = 1.2 s; fade response time = 2 s), and a higher coloring efficiency (189.86 cm2·C−1) when compared with normal PEDOT:PSS films. The introduction of EMI-TFSI in the films ultimately resulted in superior electrochemical and optical properties along with higher stability.

The aim of the study is to investigate the correlations among serum homocysteine (Hcy), D-dimer, and the risk of developing deep venous thrombosis (DVT) of the lower extremities in patients who underwent operation for lower limb fracture.

A scientific curriculum system is of vital importance for an institution's professional accreditation. This paper seeks to improve the previous College English curriculum by resolving certain recalcitrant problems impeding both teaching and learning; furthermore, it takes into account the demands of international society. By embracing an outcome-based, student-centered approach for International Engineering education accreditation, the paper emphasizes teaching targets of a College English curriculum for future engineers based on knowledge, capacity and quality. In addition, it provides a graduation requirement index matrix and, a differentiated curriculum system, which specifies a clear relationship between the system and students' outcomes. Finally, four characteristics of the system are elaborated: compulsory courses and optional courses are compared; English for General Purpose (EGP) and English for Special Purpose (ESP) are correlated; classroom teaching and extracurricular context are integrated; and formative assessment and summative assessment are combined.

The non-isothermal crystallization kinetics of the pure ethylene-methyl acrylate copolymer (EMA) and EMA/chloroprene rubber (CR) thermoplastic vulcanizate (TPV) prepared by dynamic vulcanization were extensively investigated using differential scanning calorimetry (DSC). The Avrami method modified by the Jeziorny, the Ozawa and the Mo methods were employed to characterize the non-isothermal crystallization process. The results indicated that the Avrami method modified by the Jeziorny and Mo methods effectively characterized the non-isothermal crystallization behavior of both pure EMA and EMA/CR TPV, while the behavior could not be described by the Ozawa modification method. [ABSTRACT FROM AUTHOR]

Based on the description of implementation of College English oral test from the points of the necessity, feasibility, and implementation process, this study analyzed the current situation of university students' oral English, oral English ability, the college entrance examination results, and a band-4 written test and established their correlations according to the data of Test of English Proficiency Oral (TEP oral) in Beijing Institute of Petrochemical Technology (BIPT). Furthermore, we carried out a requirement analysis through questionnaires on teachers' and students' oral ability. The current research presented the data and the problems of the college English oral test. Finally, we emphasized the issues of the implementation process and elaborated the new implementation idea of TEP oral.

High-entropy alloys (HEAs), which were introduced as a pioneering concept in 2004, have captured the keen interest of numerous researchers. Entropy, in this context, can be perceived as representing disorder and randomness. By contrast, elemental compositions within alloy systems occupy specific structural sites in space, a concept referred to as structure. In accordance with Shannon entropy, structure is analogous to information. Generally, the arrangement of atoms within a material, termed its structure, plays a pivotal role in dictating its properties. In addition to expanding the array of options for alloy composites, HEAs afford ample opportunities for diverse structural designs. The profound influence of distinct structural features on the exceptional behaviors of alloys is underscored by numerous examples. These features include remarkably high fracture strength with excellent ductility, antiballistic capability, exceptional radiation resistance, and corrosion resistance. In this paper, we delve into various unique material structures and properties while elucidating the intricate relationship between structure and performance. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizate (TPV) made from the ethylene-vinyl acetate copolymer (EVA)/nitrile rubber (NBR) blend was fabricated using the dynamic vulcanization method. Differential scanning calorimetry (DSC) was utilized to analyze the nonisothermal crystallization kinetics of both pure EVA and EVA/NBR TPV. The nonisothermal crystallization mechanism was evaluated using the Avrami method modified by Jeziorny, the Ozawa method and the Mo method. The results demonstrate that the nonisothermal crystallization of both pure EVA and EVA/NBR TPV can be adequately described by the Avrami method modified by Jeziorny and the Mo method, while the Ozawa method is not applicable. By elevating the cooling rate, there was a reduction in the crystallization temperature and t1/2 for both pure EVA and EVA/NBR TPV, while the degree of crystallization increased. At the same cooling rate, the crystallization temperature of the EVA/NBR TPV was found to be higher than that of the pure EVA, suggesting that the presence of NBR facilitated the nucleation of the EVA matrix within the EVA/NBR TPV. Moreover, a steric hindrance effect existed in the NBR phase of EVA/NBR TPV at the same cooling rate, resulting in a larger t 1/2 compared to that of the pure EVA, indicating hindered crystal growth. [ABSTRACT FROM AUTHOR]

The microwave absorption performance of high-entropy alloys (HEAs) can be improved by reducing the reflection coefficient of electromagnetic waves and broadening the absorption frequency band. The present work prepared flaky irregular-shaped Al1.5Co4Fe2Cr and Al1.5Co4Fe2Cr@rGO alloy powders by mechanical alloying (MA) at different rotational speeds. It was found that the addition of trace amounts of reduced graphene oxide (rGO) had a favorable effect on the impedance matching, reflection loss (RL), and effective absorbing bandwidth (EAB) of the Al1.5Co4Fe2Cr@rGO HEA composite powders. The EAB of the alloy powders prepared at 300 rpm increased from 2.58 GHz to 4.62 GHz with the additive, and the RL increased by 2.56 dB. The results showed that the presence of rGO modified the complex dielectric constant of HEA powders, thereby enhancing their dielectric loss capability. Additionally, the presence of lamellar rGO intensified the interfacial reflections within the absorber, facilitating the dissipation of electromagnetic waves. The effect of the ball milling speed on the defect concentration of the alloy powders also affected its wave absorption performance. The samples prepared at 350 rpm had the best wave absorption performance, with an RL of −16.23 and −17.28 dB for a thickness of 1.6 mm and EAB of 5.77 GHz and 5.43 GHz, respectively. [ABSTRACT FROM AUTHOR]

In order to reduce the clock offset caused by network delay jitter, network asymmetry, clock drift and clock frequency difference in the clock synchronization process of IEEE1588, a modified Strong Tracking Adaptive Kalman Filter (MSTAKF) algorithm was proposed. The Kalman filter model established by the algorithm is based on clock offset, network delay, frequency deviation and asymmetry ratio. The filter includes the modified strong tracking algorithm based on fuzzy logic and hypothesis test proposed in this paper, which can effectively eliminate the influence of outliers, and finally make the model tracking effect better. In addition, the modified Sage‐Husa algorithm based on Cholesky decomposition is also included, which makes the measurement noise more stable and ensures the positivity of the measurement noise covariance. The experimental results show that the proposed MSTAKF is smoother than Karman filter (KF), Sage‐Husa adaptive Kalman filter (AKF) and strong tracking Sage‐Husa adaptive Kalman filter (STAKF). Compared with these filter algorithms after testing in the LAN environment, the precision improvement and accuracy rate are significantly improved. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Cobalt blue ceramic pigments mainly consisting of CoAl2O4 are subject to the difficulty of color control. Here, a perspective is reported regarding research on the reasons for color change based on the control of the heat treatment and ratio of components. Macroscopically, the composition of pigment powders determines the color. Microscopically, the crystallite characters including size, cation distribution, and structure have an important effect on the color. The ingredient, structural, and color properties of the pigment powders are analyzed using thermo gravimetry–differential scanning calorimetry (TG–DSC), X-ray diffraction (XRD) measurement, Rietveld refinement, energy dispersive spectrometer (EDS), and colorimetry analysis. The color is proven to be associated with cation distribution, such as that of Co2+ and Co3+. It is indicated that high heating temperature, long heating time, and a large proportion of Al3+ can, respectively, induce the Co2+ and Al3+ in tetrahedral and octahedral sites. [ABSTRACT FROM AUTHOR]

The utilization of Co-Cr-Fe-based black pigments bears considerable significance within the realm of commercial ceramic pigments, owing to their distinctive spinel structure, remarkable high-temperature stability, and exceptional chromatic attributes. This study delves into the synthesis of diverse black pigment configurations by employing the co-precipitation method, leveraging the interplay of these three metallic oxides. This investigation encompasses a comprehensive scrutiny of ion valences, crystal structures and parameters, colorimetric properties, and their interrelationships. The methodology integrates the response surface methodology (RSM) framework, using theoretical formulations to navigate the material ratios and elucidating the associations between the resultant compositions and color coordinate values, aligned with the CIE-Lab* colorimetric methodology. The derived predictive models yielded an optimized black pigment composition, characterized by heightened black intensity and a refined formulation. [ABSTRACT FROM AUTHOR]

The formation of lithiophobic inorganic solid electrolyte interphase (SEI) on Li anode and cathode electrolyte interphase (CEI) on the cathode is beneficial for high‐voltage Li metal batteries. However, in most liquid electrolytes, the decomposition of organic solvents inevitably forms organic components in the SEI and CEI. In addition, organic solvents often pose substantial safety risks due to their high volatility and flammability. Herein, an organic‐solvent‐free eutectic electrolyte based on low‐melting alkali perfluorinated‐sulfonimide salts is reported. The exclusive anion reduction on Li anode surface results in an inorganic, LiF‐rich SEI with high capability to suppress Li dendrite, as evidenced by the high Li plating/stripping CE of 99.4% at 0.5 mA cm−2 and 1.0 mAh cm−2, and 200‐cycle lifespan of full LiNi0.8Co0.15Al0.05O2 (2.0 mAh cm−2) || Li (20 µm) cells at 80 °C. The proposed eutectic electrolyte is promising for ultrasafe and high‐energy Li metal batteries. [ABSTRACT FROM AUTHOR]

Owing to their biocompatibility, chemical stability, film-forming ability, cost-effectiveness, and excellent electroactive properties, poly(vinylidene fluoride) (PVDF) and PVDF-based polymers are widely used in sensors, actuators, energy harvesters, etc. In this review, the recent research progress on the PVDF phase structures and identification of different phases is outlined. Several approaches for obtaining the electroactive phase of PVDF and preparing PVDF-based nanocomposites are described. Furthermore, the potential applications of these materials in wearable sensors and human energy harvesters are discussed. Finally, some challenges and perspectives for improving the properties and boosting the applications of these materials are presented. [ABSTRACT FROM AUTHOR]

In order to respond to the national goal of "carbon neutralization" and make more rational and effective use of photovoltaic resources, combined with the actual photovoltaic substation project, a fixed adjustable photovoltaic support structure design is designed. By comparing the advantages and disadvantages of the existing support, an innovative optimization design is proposed, and the mechanical structure of the support is analyzed by ANASYS to check the rationality of the design. Saving construction materials and reducing construction costs provide a basis for the reasonable design of photovoltaic power station supports, and also provide a reference for the structural design of fixed and adjustable supports. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the antitumor effect and associated molecular mechanisms of the copper (II) complex of salicylate phenanthroline [Cu(sal)(phen)] against hepatocellular carcinoma (HCC). Cu(sal)(phen) inhibited the proliferation of HCC cells (HepG2 and HCC‐LM9) and induced apoptosis of HCC cells in a dose‐dependent manner by upregulating mitochondrial reactive oxygen species (ROS) production. The expression of the antiapoptotic proteins survivin and Bcl‐2 was decreased, while the expression of the DNA damage marker γ‐H2AX and the apoptotic marker cleaved PARP was upregulated with Cu(sal)(phen) treatment. In vivo, the growth of HepG2 subcutaneous xenograft tumors was greatly attenuated by Cu(sal)(phen) treatment. Immunohistochemistry staining showed that the expression of survivin, Bcl‐2, and Ki67 in the tumor was downregulated by Cu(sal)(phen). Toxicity experiments with BALB/c mice revealed that Cu(sal)(phen) is a relatively safe drug. Our results indicate that Cu(sal)(phen) possesses great potential as a therapeutic drug for HCC. [ABSTRACT FROM AUTHOR]

Excess reactive oxygen species (ROS) can cause an imbalance between oxidation and anti-oxidation, leading to the occurrence of oxidative stress in the body. The most common product of ROS-induced base damage is 8-hydroxyguanine (8-oxoG). Failure to promptly remove 8-oxoG often causes mutations during DNA replication. 8-oxoG is cleared from cells by the 8-oxoG DNA glycosylase 1 (OGG1)-mediated oxidative damage base excision repair pathway so as to prevent cells from suffering dysfunction due to oxidative stress. Physiological immune homeostasis and, in particular, immune cell function are vulnerable to oxidative stress. Evidence suggests that inflammation, aging, cancer, and other diseases are related to an imbalance in immune homeostasis caused by oxidative stress. However, the role of the OGG1-mediated oxidative damage repair pathway in the activation and maintenance of immune cell function is unknown. This review summarizes the current understanding of the effect of OGG1 on immune cell function. [ABSTRACT FROM AUTHOR]