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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.

The operating environment of overhead lines in mining areas is harsh. The lines are easily affected by external factors, leading to line breakage. It is necessary to accurately evaluate the risk level of external breakage of overhead lines in mining areas. However, existing qualitative evaluation methods have shortcomings such as strong subjectivity and poor comparability of evaluation results. Although quantitative evaluation methods have high objectivity, the accurate evaluation is based on a large amount of high-quality data. In order to balance the objectivity of the evaluation results and the difficulty of obtaining evaluation data, the likelihood exposure consequence (LEC) method in semi quantitative evaluation method is adopted. Based on the actual operating environment of mining area lines, an improved LEC method is proposed for the risk assessment of external breakage of overhead lines in mining areas. Firstly, by analyzing the actual operating environment of overhead lines in mining areas, the main risk factors of external breakage are identified. The risk assessment index system for external breakage of overhead lines in mining areas is constructed. Secondly, using the YOLOv5 based image recognition strategy to identify the sources of external breakage risk in the line environment, real-time acquisition of external breakage risk data of the line is achieved. It overcomes the shortcomings of poor real-time performance and insufficient data volume obtained manually by traditional LEC methods. Thirdly, the element assignment rules of the LEC method are improved. The elements are assigned based on image recognition results to achieve real-time evaluation of the risk of external breakage to the line. It improves the objectivity of the evaluation results and solves the problem of the traditional LEC method's element assignment relying on the personal experience of the evaluator. Finally, in order to measure the superimposed impact of various risks, the analytic hierarchy process is used to determine the weight of each risk evaluation index. Ultimately, the comprehensive assessment of the risk of external breakage to overhead lines in mining areas is achieved. A case study is conducted during the actual operation of an open-pit coal mine. The results show that this method can effectively evaluate the risk level of external breakage of overhead lines in specific scenarios.

Hormone replacement therapy (HRT) is not recommended for treating learning and memory decline in menopausal women because it exerts adverse effects by activating classic estrogen receptors ERa and ERp. The membrane estrogen receptor G protein-coupled receptor 30 (GPR30) has been reported to be involved in memory modulation; however, the underlying mechanisms are poorly understood. Here, we found that GPR30 deletion in astrocytes, but not in neurons, impaired learning and memory in female mice. Astrocytic GPR30 depletion induced A1 phenotype transition, impairing neuronal function. Further exploration revealed that Praja1 (PJA1), a RING ubiquitin ligase, mediated the effects of astrocytic GPR30 on learning and memory by binding to Serpina3n, which is a molecular marker of neuroinflammation in astrocytes. GPR30 positively modulated PJA1 expression through the CREB signaling pathway in cultured murine and human astrocytes. Additionally, the mRNA levels of GPR30 and PJA1 were reduced in exosomes isolated from postmenopausal women while Serpina3n levels were increased in the plasma. Together, our findings suggest a key role for astrocytic GPR30 in the learning and memory abilities of female mice and identify GPR30/PJA1/Serpina3n as potential therapeutic targets for learning and memory loss in peri- and postmenopausal women., Introduction The process of learning and memory is how people acquire, encode, store, retain and later retrieve information in the brain. For perimenopausal women, learning and memory abilities decline rapidly [...]