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Real-time sensing of hot spot temperature in three-core cable joints is of significant importance for studying operation safety of cables， temperature rise， and dynamic load carrying capacity assessment. Therefore， focusing on 10 kV three-core cable joints and considering the variations in structures， materials， and on-site process for different types of joints， the paper constructs a simulation model for cable joint temperature fields and analyzes the temperature field distribution rules of the joints. Moreover， the paper establishes a unified inverse model for axial temperature of conductor based on axial heat flow. By employing single factor variation and orthogonal combination methods， the paper analyzes the impact of material parameter variations on the fitting degree and sensitivity of the axial inverse model for joint conductors. Simulation results demonstrate that the sensitivity coefficient and fitting goodness of the inverse model for axial temperature vary slightly， indicating good robustness for different structural， material， and on-site process variations.

Objective To investigate the effect of hypoxia combined with propofol on immature Sprague-Dawley (SD) rat hippocampal neurons through ferroptosis. Methods A total of 168 7-day-old SD rats (half male and half female, 15.59±1.13 g) were randomly divided into 6 groups (n=28): lipid emulsion solvent+50% oxygen (CO), lipid emulsion solvent+air (CA), lipid emulsion solvent+18% oxygen (CH), propofol+50% oxygen (PO), propofol+air (PA), and propofol+18% oxygen (PH) groups.The rats in the propofol group were intraperitoneally injected with 50 mg/kg propofol, and those in the lipid emulsion group were intraperitoneally injected with 5 mL/kg lipid emulsion, once a day for 7 consecutive days.After injection, the mice were put into warm chambers with oxygen concentration of 50%, 21% and 18%(38℃) respectively.After the righting reflex recovered, the mice were immediately put back into the normoxic environment for feeding by their mothers.The respiratory rate (RR) and blood oxygen saturation (SpO2) of immature SD rats were observed and monitored after propofol anesthesia.The morphological changes of mitochondria in hippocampal neurons were observed by transmission electron microscopy.The contents of Fe2+ and malondialdehyde (MDA) in the hippocampus were detected by biochemical assay, and the protein expression of transferrin receptor (TFRC) in the hippocampus was detected by Western blotting. Results The results of RR and SpO2 monitoring showed that compared with the corresponding lipid emulsion group, only RR in the PO group was decreased (CO vs PO, P < 0.01), while RR and SpO2 in the PA and PH groups were decreased (CA vs PA, CH vs PH, P < 0.01).Transmission electron microscopy displayed that the mitochondria in the hippocampal neurons of the PA and PH groups were generally swollen, with dissolved and disappeared mitochondrial cristae.The results of the biochemical assay showed that the Fe2+ content and MDA level in the PO, PA, and PH groups were increased than those in the corresponding lipid emulsion groups (P < 0.01).Compared with the PO group, the content of Fe2+ and MDA were increased in the PA and PH groups (P < 0.05).Western blotting indicated that compared with the corresponding lipid emulsion group, the expression level of TFRC in the PO, PA, and PH groups was increased (P < 0.05), while the level was increased in the PA and PH groups than the PO group (P < 0.05). Conclusion Hypoxia aggravates the damage of hippocampal neurons induced by propofol in immature SD rats, and the mechanism is related to the ferroptosis of hippocampal tissue.

Objective To explore the role of parthanatos in propofol-induced injury in PC12 cells under hypoxic conditions. Methods PC12 cells were induced to differentiate with mouse nerve growth factor (NGF), and randomly divided into normal control (NC) group, lipid emulsion solvent+room air (CA) group, lipid emulsion solvent+hypoxia control (CH) group, propofol+room air (PA) group, propofol+hypoxia (PH) group, and 3-AB (PARP-1 inhibitor) group. Lactate dehydrogenase (LDH) kit and flow cytometry were adopted to detect the LDH level in the supernatant and the cell apoptosis, respectively. The mRNA levels of poly ADP-ribose polymerase 1 (PARP-1) and apoptosis-inducing factor (AIF) were determined by RT-qPCR, and the protein levels of AIF, PARP-1 and polymerized ADP-ribose (PAR) in each group were measured by Western blotting. The nuclear distribution of AIF in PC12 cells was observed by immunofluorescence assay. Results As compared with the NC and CA groups, the levels of LDH and apoptosis were significantly enhanced in the PA and PH groups (P < 0.01); the mRNA and protein levels of PARP-1 and AIF (P < 0.05) were increased; and the accumulation of cytoplasmic PAR (P < 0.01) and AIF nuclear translocation (P < 0.01) were observed as well. In comparison with the CH and PA groups, the levels of LDH and cell apoptosis (P < 0.01), the mRNA and protein expression of PARP-1 (P < 0.01), the formation of cytoplasmic PAR (P < 0.01), and the AIF nuclear translocation (P < 0.01) were all augmented in the PH group. Pretreatment with PARP-1 inhibitor 3-AB notably reversed the increase in LDH level and cell apoptosis induced by hypoxia combined with propofol (P < 0.01), and restrained the up-regulation of PARP-1, AIF and PAR(P < 0.01). Conclusion Propofol causes parthanatos of PC12 cells under hypoxic conditions, and inhibition of parthanatos can alleviate the damage in PC12 cells induced by propofol combined with hypoxia.

Gastric cancer (GC) is one of the most common malignancies in digestive system. Accumulating evidence reveals the critical role of long noncoding RNAs (lncRNAs) in GC development. The study aimed to explore the functions and mechanism of lncRNA actin alpha 2, smooth muscle antisense RNA 1 (ACTA2-AS1) in GC. Reverse transcription-quantitative polymerase chain reaction analyses and subcellular fractionation assays showed that ACTA2-AS1 was lowly expressed in GC cells and was mainly distributed in the cytoplasm. Overexpressed ACTA2-AS1 inhibited GC cell viability, proliferation, migration, invasion, and epithelial-mesenchymal transition process, as suggested by cell counting kit-8 assays, colony formation assays, wound healing assays, Transwell assays and Western blot analyses. Mechanistically, ACTA2-AS1 served as a competing endogenous RNA (ceRNA) to bind with miR-378a-3p and thereby, antagonized the inhibitory effect of miR-378a-3p on the expression of messenger RNA phosphatidylinositol specific phospholipase C X domain containing 2 (PLCXD2). The binding capacity between miR-378a-3p and ACTA2-AS1 (or PLCXD2) was detected by RNA pulldown assays, luciferase reporter assays and RNA immunoprecipitation assays. Moreover, PLCXD2 knockdown rescued the inhibitory effect of ACTA2-AS1 overexpression on malignant behaviors of GC cells. Overall, ACTA2-AS1 inhibits malignant phenotypes of GC cells by acting as a ceRNA to target miR-378a-3p/PLCXD2 axis.

Obiective To investigate the current status of remaining teeth and edentulous jaw arch of people aged 35⁃44, 55⁃64 and 65⁃ 74 in Guangdong province. Methods An equal⁃ sized stratified multi⁃stage randomly sampling design was applied to select a total of 288 Guangdong residents in urban and rural areas, and the subjects were between the age of 35⁃44, 55⁃64 and 65⁃74, with a gender ratio of half to half. The status of remaining teeth and edentulous jaw arch were assessed according to the Guideline for the 4th National Oral Health Survey. Results 88.89% subjects in the 35⁃44 year group had more than 28 teeth and 100% subjects had more than 20 teeth, with an average of 29.88 teeth remaining and no edentulous jaw. The average remaining teeth was 26.06 in the group of 55 ⁃ 64 year, with 87.50% subjects having more than 20 teeth, 59.03% subjects having 28 or more teeth, 4.16% subjects having single edentulous jaw arch, and 1.04% subjects having both edentulous jaw arch. 73.96% and 35.07% subjects in the group of 65⁃74 year had 20 above or 28 above remaining teeth, respectively, and the average teeth was 22.94. There were 8.34% subjects having single edentulous jaw arch and 1.39% subjects having both edentulous jaws. In the 35⁃44 and 65⁃74 year group, the prevalence of missing teeth in the female was significantly higher than the male (P < 0.05), while no significant difference was found between urban and rural areas (P > 0.05). More remaining teeth were noticed in current survey (2015) when compared to the data in 2005 (P < 0.05). Conclusion The 35⁃44 year people have few lost teeth, and over half of the elderly people have several lost teeth. Elderly people with edentulous arch are very few.

Teacher shortage is a major hindrance to China's rural education growth in underdeveloped areas, as well as one of the main causes of educational injustice. We conducted a survey of 5,554 teachers from 117 towns in H province in the Wuling Mountains Zone to investigate the issue of rural school teacher supply. From geographical, emotional, and institutional perspectives, we used a polynomial logit model to examine the validity of the "hometown effects" hypothesis. The findings showed that hometown effects exist in China in all three dimensions. The institutional hometown effects are the most pronounced; when compared to open recruitment, teachers sourced through teacher supply augmentation programs (such as the Secondary Normal Graduates Program, Special Position Program, and Targeted Position Program) are more likely to teach in rural schools, particularly more disadvantaged village primary schools or teaching sites. China's policy of increasing teacher supply has had a considerable positive influence on rural school staffing. Students from rural areas make better teacher candidates; feelings for hometowns should be encouraged among normal school or university students in pre-service education; and the implementation of teacher support policies should be emphasized to retain rural teachers and improve their teaching quality.

Key messageThe CsGAI gene, identified by map-based, was involved in regulating seed germination in low temperature via the GA and ABA signaling pathways. Low temperature reduces the percentage of seeds germinating and delays seed germinating time, thus posing a threat to cucumber production. However, the molecular mechanism regulating low temperature germination in cucumber is unknown. We here dissected a major quantitative trait locus qLTG1.1 that controls seed germination at low temperature in cucumber. First, we fine-mapped qLTG1.1 to a 46.3-kb interval, containing three candidate genes. Sequence alignment and gene expression analysis identified Csa1G408720 as the gene of interest that was highly expressed in seeds, and encoded a highly conserved, low temperature-regulated DELLA family protein CsGAI. GUS expression analysis indicated that higher promoter activity underscored higher transcriptional expression of the CsGAI gene. Consistent with the known roles of GAI in ABA and GA signaling during germination, genes involved in the GA (CsGA2ox, CsGA3ox) and ABA biosynthetic pathways (CsABA1, CsABA2, CsAAO3 and CsNCED) were found to be differently regulated in the tolerant and sensitive genotypes under low temperatures, and this was reflected in differences in their ratio of GA-to-ABA. Based on these data, we proposed a working model explaining how CsGAI integrates the GA and ABA signaling pathways, to regulate cucumber seed germination at low temperature, thus providing new insights into this mechanism.