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In this work, the oxygen barrier property of polyethylene terephthalate (PET) films was enhanced by optimizing the 'active' and 'passive' synergistic barrier approaches, that is, integration of high barrier material polyethylene naphthalate (PEN) and oxygen scavengers along with catalyst with PET before biaxially stretching the PET blended films. When the PEN content in the PET blended films reached 50wt%, the oxygen permeability coefficient was significantly reduced to 0.9687 cc*mil*[m.sup.-2]*[day.sup.-1] 0.1 [MPa.sup.-1], showing an enhancement of 117.4 times compared to the pure PET film. Furthermore, the water vapor permeability coefficient was reduced to 8.0208 g*mil*[m.sup.-2]*[day.sup.-1], representing a 45.5% reduction in comparison to the pristine PET film. It also maintained a higher transverse and longitudinal tensile strength (110.5 and 127.2 MPa) than PET film only with oxygen scavengers and catalyst (53.5 and 78.0 MPa). This work presents a viable and practical approach to endow PET materials with simultaneously enhanced oxygen, water barrier performance, and mechanical property. Highlights * The OPC of PET film was as low as 0.9687 cc*mil*[m.sup.-2]*[day.sup.-1]*0.1 [MPa.sup.-1]. * The 'active' and 'passive' barrier techniques together reduced the OPC of PET film. KEYWORDS blow molding, oxygen barrier, oxygen scavenging, polyethylene naphthalate, polyethylene terephthalate, water barrier, 1 | INTRODUCTION Polyethylene terephthalate (PET) is widely used as a thermoplastic polyester in food packaging due to its excellent mechanical property, affordability, as well as high transparency. (1,2) Although [...]

In order to investigate the effect of vacuum precooling treatment on the lignification of Tricholoma matsutake during storage, the changes in the hardness of cap and stalk, pulp firmness, lignin, chitin and cellulose contents, and the activities of cellulase (CX), phenylalanine ammonia-lyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO) were studied during storage. The results showed that compared with the control group, vacuum precooling treatment could significantly inhibit the decline in the hardness of cap and stalk and pulp firmness, effectively inhibit the degradation of chitin and the increase of CX activity in the cell wall, maintain a higher cellulose content, and delay the accumulation of lignin. In addition, it could decrease the peak PAL activity of cap and stalk by 8.2% and 2.9%, the peak POD activity by 10% and 3.7%, and the peak PPO activity by 23.1% and 5.2%, respectively. In addition, compared with the cap, the peak time of lignification in the stalk was earlier, and lignification phenomenon was more likely to occur in the stalk. Therefore, vacuum precooling treatment can delay the lignification process and maintain the quality of T. matsutake.

Molecular oxygen activation often suffers from high energy consumption and low efficiency. Developing eco-friendly and effective photocatalysts remains a key challenge for advancing green molecular oxygen activation. Herein, graphitic carbon nitride (g-C3N4) with abundant hydroxyl groups (HCN) was synthesized to investigate the relationship between these polar groups and molecular oxygen activation. The advantage of the hydroxyl group modification of g-C3N4 included narrower interlayer distances, a larger specific surface area and improved hydrophilicity. Various photoelectronic measurements revealed that the introduced hydroxyl groups reduced the charge transfer resistance of HCN, resulting in accelerated charge separation and migration kinetics. Therefore, the optimal HCN-90 showed the highest activity for Rhodamine B photodegradation with a reaction time of 30 min and an apparent rate constant of 0.125 min−1, surpassing most other g-C3N4 composites. This enhanced activity was attributed to the adjusted band structure achieved through polar functional group modification. The modification of polar functional groups could alter the energy band structure of photocatalysts, narrow band gap, enhance visible-light absorption, and improve photogenerated carrier separation efficiency. This work highlights the significant potential of polar functional groups in tuning the structure of g-C3N4 to enhance efficient molecular oxygen activation. [ABSTRACT FROM AUTHOR]

The accurate prediction of photovoltaic (PV) power is crucial for planning, constructing, and scheduling high‐penetration distributed PV power systems. Traditional point prediction methods suffer from instability and lack reliability, which can be effectively addressed through interval prediction. This study proposes a short‐term PV power interval prediction method based on the framework of sparrow search algorithm (SSA)‐variational mode decomposition (VMD)‐convolutional neural network (CNN)‐gate recurrent unit (GRU). First, PV data undergo similar day clustering based on permutation entropy and VMD is applied to solar radiation signals with high correlation. Then, the hyperparameters of GRU are optimized by SSA according to the comprehensive evaluation indicator of interval prediction proposed in this study. Subsequently, quantile prediction results are obtained based on CNN‐GRU using the optimal parameters from SSA optimization. Finally, the prediction interval is composed of multiple quantile prediction results. A MATLAB R2022b program is developed to compare different prediction methods. The results demonstrate that compared to single neural network methods, the proposed method effectively improves the coverage width‐based criterion. In the interval prediction of sunny and rainy similar days, the comprehensive evaluation indicators of the proposed method are only 54.3% and 37.4% of the single GRU, respectively, indicating significantly improved interval prediction accuracy. [ABSTRACT FROM AUTHOR]

Distributed micro‐energy harvesting devices offer the flexibility, sustainability, and multi‐scenario applicability that will be critical to wearable electronic products in the Internet of Things. The radiofrequency and triboelectric (RF‐TE) hybrid energy harvester (HEH) concept and prototype is presented for the first time, to simultaneously capture the energy from ambient electromagnetic waves and biological motions. The proposed hybrid energy harvesting system consists of a wearable rectenna, a triboelectric nanogenerator (TENG), and a power management circuit (PMC). Among them, the all‐fabric rectenna exhibits good impedance matching characteristics in the ISM frequency. The flexible TENG unit can generate a maximum power density of 0.024 µW cm−2. The designed multifunctional fabric‐based PMC can considerably enhance the controllability of harvested hybrid energy. Additionally, a normalizable fabric circuit board quasi surface mount technology (FCB‐SMT) is proposed to integrate all modules on the same fabric substrate in one step, making the entire system superior mechanical robustness. The proposed wearable fabric‐based RF‐TE hybrid energy harvester is capable of successfully driving consumer electronics (such as sensors, watches, etc.). It provides a new energy solution strategy for self‐powered wearable electronic devices and is anticipated to encourage the efficient utilization of renewable energy. [ABSTRACT FROM AUTHOR]

The existing diagnostic methods of epilepsy have great limitations, and more reliable and less difficult diagnostic methods are needed. We collected serum samples of adult patients with first-diagnosed epilepsy (EPs) and seizure control patients (EPRs) for non-targeted metabolomics detection and found that they were both significantly altered, with increased expression of nicotine addiction, linoleic acid metabolism, purine metabolism, and other metabolic pathways. The diagnostic model based on 4 differential metabolites achieved a diagnostic efficiency of 99.4% in the training cohort and 100% in the validation cohort. In addition, the association analysis of oral flora, serum metabolism, and clinical indicators also provided a new angle to analyze the mechanism of epilepsy. In conclusion, this study characterized the serum metabolic characteristics of EPs and EPRs and the changes before and after epilepsy control based on a large cohort, demonstrating the potential of metabolites as non-invasive diagnostic tools for epilepsy., (© 2024. The Author(s).)

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in December 2019 with staggering economic fallout and human suffering. The unique structure of SARS-CoV-2 and its underlying pathogenic mechanism were responsible for the global pandemic. In addition to the direct damage caused by the virus, SARS-CoV-2 triggers an abnormal immune response leading to a cytokine storm, culminating in acute respiratory distress syndrome and other fatal diseases that pose a significant challenge to clinicians. Therefore, potential treatments should focus not only on eliminating the virus but also on alleviating or controlling acute immune/inflammatory responses. Current management strategies for COVID-19 include preventative measures and supportive care, while the role of the host immune/inflammatory response in disease progression has largely been overlooked. Understanding the interaction between SARS-CoV-2 and its receptors, as well as the underlying pathogenesis, has proven to be helpful for disease prevention, early recognition of disease progression, vaccine development, and interventions aimed at reducing immunopathology have been shown to reduce adverse clinical outcomes and improve prognosis. Moreover, several key mutations in the SARS-CoV-2 genome sequence result in an enhanced binding affinity to the host cell receptor, or produce immune escape, leading to either increased virus transmissibility or virulence of variants that carry these mutations. This review characterizes the structural features of SARS-CoV-2, its variants, and their interaction with the immune system, emphasizing the role of dysfunctional immune responses and cytokine storm in disease progression. Additionally, potential therapeutic options are reviewed, providing critical insights into disease management, exploring effective approaches to deal with the public health crises caused by SARS-CoV-2., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Mi, Liu and Rong.)