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Given the frequent missing and false alarms of partial discharge insulation defects in on-site gas insulated substation (GIS), intermittent discharge characteristics tests are conducted in this article to study the discharge characteristics of common solid insulation defects inside GIS at different temperatures in the actual operating temperature range of GIS. In this paper, the platform of GIS electric thermal coupling intermittent discharge simulation test is built with the pulse current method, ultrahigh frequency (UHF) method, ultrasonic method and gas characteristic component detection method used in combination to obtain and analyze the intermittent discharge characteristic data of solid insulation defects at different temperatures. It is found out that both UHF detection method and pulse current detection method can effectively detect the intermittent discharge UHF signals of test defects at different temperatures, while ultrasonic and gas characteristic component detection methods are not applicable to effectively collect effective discharge data. The intermittent discharge voltage of metal pollution defects on the surface of solid insulation and internal air gap defects shows a negative correlation with temperature. The intermittent discharge voltage of pollution defects shows a significant trend of linear decrease, while the intermittent discharge voltage of air gap defects shows a significant decrease first and then a trend of slow-paced linear decrease. The average discharge capacity and UHF signal amplitude of intermittent discharge of pollution defects exhibit a positive correlation with the increase of temperature. The intermittency of pollution defect discharge increases with the extension of discharge time at different temperatures, while the interval of gap defect discharge can change from second level to microsecond level at 26 ℃, 40 ℃ and 50 ℃, posing a risk of breakdown discharge. The research results obtained in this article further enrich the theoretical system of GIS intermittent discharge and improve the effective diagnosis rate of on-site GIS intermittent discharge.

In this study, free radical oxidation was chosen to induce covalent reaction of gliadin (GL) with epigallocatechin gallate. The effects of different ultrasound (US) powers on the enhancement of the covalent reaction were compared with the aim of improving the bioavailability of polyphenols in protein modification. Covalent modification of polyphenols was verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), high-performance liquid chromatography (HPLC) and the Folin-Ciocalteu assay. The structural changes of the covalent complexes were analyzed by ultraviolet (UV) spectroscopy and circular dichroism (CD) spectroscopy. The results showed that US disrupted weak intra-protein forces, which caused molecular depolymerization. The hydrophilic/hydrophobic amino acid residues of the protein were shifted and the tertiary structure tended to be looser, and this process altered the distribution of groups on the molecule surface and increased the water solubility of the protein. Furthermore, the shift in the spatial structure of GL resulted in the exposure of more enzyme cleavage sites, making its digestion easier. The synergistic effect of US and free radical oxidation increased the loading of antioxidant molecules onto the covalent complexes, resulting in stronger free radical scavenging activity.

Objective To investigate the prognostic factors of breast cancer brain metastasis (BCBM), and to construct and validate a prediction model for prognosis of BCBM patients. Methods A case-control trial was designed and conducted in this study. A total of 1 133 BCBM patients were screened out from the Surveillance, Epidemiology, and End Results (SEER) database from 2016 to 2020, and were randomly assigned to a training set (n=793) and an internal validation set (n=340) at a ratio of 7 ∶3. The prognostic factors were determined with univariate and multivariate Cox regression analyses, and a nomogram prediction model was constructed. The discrimination, prediction and calibration of the nomograms were evaluated by C-index, receiver operating characteristic (ROC) curve and calibration curve. External validation of the nomogram prediction model was performed in 73 BCBM patients admitted to our hospital from 2004 to 2019. Results Multivariate Cox regression analysis revealed that age, molecular type, surgery, radiotherapy, chemotherapy, lung metastasis and liver metastasis were identified as independent factors (P

Objective To investigate the associated factors of BRAF V600E gene mutation in patients classified as Bethesda I~V nodes by fine needle aspiration cytology (FNAC) but confirmed as papillary thyroid carcinoma (PTC) by postoperative histopathology. Methods A retrospective analysis was performed on the clinical data of the patients with FNAC classification of Bethesda I~V but confirmed by postoperative histopathology as PTC who were treated in our hospital from June 2020 to June 2021. According to the results of BRAF V600E gene test in preoperative puncture specimens, the patients were divided into mutation positive group and negative group. The clinical data were compared between the 2 groups, and the indicators associated with BRAF V600E gene mutation were analyzed. Results Of the 127 enrolled patients, they were 27 males (21.26%) and 100 females (78.74%), with a mean age of 42.51 years (median age: 42 years). Eight-two patients (64.57%) harbored the BRAF V600E gene mutation, and 45 (35.43%) did not. Univariate analysis showed that there were significant differences in the capsular boundary, nodule morphology, abnormal cervical lymph nodes, TIRADS grade, FNAC class, and T-stage between the 2 groups (P < 0.05). Multivariate logistic regression analysis indicated that capsular boundary and abnormal cervical lymph nodes were independent influencing factors of BRAF V600E gene mutation in these patients. ROC curve analysis suggested that the area under the curve (AUC) was 0.921 (95%CI: 0.876~0.967), with a sensitivity and specificity of 82.9% and 86.7%, respectively, when taking capsular boundary, nodule morphology, abnormal cervical lymph nodes and TIRADS grade combined together. Conclusion BRAF V600E gene mutation is associated with capsular boundary, nodule morphology, abnormal cervical lymph nodes on ultrasonogram, TIRADS grade, FNAC class, and T-stage in PTC patients. Among them, ultrasonographic indication of abnormal cervical lymph nodes and the boundary between nodules and capsule can be used to predict BRAF V600E gene mutation.

The chemical composition and quality of honey are influenced by its botanical, geographic, and entomological origins, as well as climatic conditions. In this study, the physicochemical characteristics, microbial communities, and hydrocarbon compounds of honey produced by Apis mellifera, Apis cerana, Apis laboriosa, Apis dorsata, and Apis florea were elucidated. The physicochemical profile of the honey exhibited significant differences across species, including moisture content (18.27–23.66%), fructose (33.79–38.70%), maltose (1.10–1.93%), electrical conductivity (0.37–0.74 mS/cm), pH (3.36–3.72), diastase activity (4.50–29.97 diastase number), and color (37.90–102.47 mm). Microbial analysis revealed a significant abundance of lactic acid bacteria, particularly the Apilactobacillus genus in A. laboriosa honey and the Lactobacillus in A. florea honey, indicating significant probiotic potential. Chemometric methods, principal component analysis, hierarchical cluster analysis, and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to classify the honey samples based on the 12 beeswax-derived hydrocarbons. The OPLS-DA model demonstrated 100% accuracy in predicting the entomological origin of honey, indicating that specific hydrocarbons are reliable markers for honey classification. [ABSTRACT FROM AUTHOR]

This study proposes a practical approach to assessing the need for and determining the transitioning parameters from age-specific to size-specific dose protocols in paediatric head computed tomography examinations. It was designed to begin with the two different age-specific protocols currently applied on paediatric patients of 1 y ≤ age ≤ 6 y (21.34 mGy) and those of age >6 y (34.73 mGy). One characteristic size (HDthreshold) was found by measuring anteroposterior head diameter on historical topograms and used with age to set 135 cases into four groups for investigation (A, ≤6y, ≤HDthreshold; B, ≤6y, >HDthreshold; C, >6y, ≤HDthreshold; and D, >6 y, >HDthreshold). The image quality was compared in both subjective and objective manners. Results suggest patients in Group C may have received a potential overdose (38%), while the exposure setting for Group D may replace that for B. The proposed strategy was sufficient to assess the necessity and determine the transitioning parameters from age- to size-specific dose protocols. [ABSTRACT FROM AUTHOR]

Simple Summary: κ-casein polymorphism is closely related to productive performance and dairy processing performance. In this study, the polymorphism of CSN3 3'untranslated regions (3'UTR) in Chinese Holstein cows and the effect of polymorphism were investigated. The CSN3 3'UTR polymorphism was characterized by two main haplotypes. There were significant differences in gene and protein expression of CSN3 between the two haplotypes. The binding abilities of bta-miR-708 to recombinant vectors with these two haplotypes were significantly different, potentially explaining why the gene and protein expressions of CSN3 with two haplotypes were different. κ-casein (CSN3) polymorphisms are closely related to productive performance and dairy processing performance. In this study, CSN3 3'UTR polymorphisms in Chinese Holstein cows (n = 50) and the effects of these polymorphisms on the gene expression of four caseins, the protein expression of κ-casein, the binding of microRNAs (miRNAs), and cow production performance were investigated. There were two main haplotypes for the CSN3 3'UTR in Chinese Holstein cows: Haplotype 1 (0 mutations, n = 16) and Haplotype 10 (a combination of 7 mutations, n = 17). The gene and protein expression levels of CSN3 in Haplotype 1 were significantly greater than those in Haplotype 10 (p < 0.05). The ability of bta-miR-708 to bind to the CSN3 3'UTR with Haplotype 10 was significantly greater than that with Haplotype 1 (p < 0.05), potentially explaining why the gene and protein expression of CSN3 with Haplotype 10 were lower than those with Haplotype 1. Dairy herd improvement (DHI) data, including 305-d milk production, fat-corrected milk, fat (%), protein (%), and fat/protein ratio, were not significantly different between the two haplotypes (p > 0.05). Results suggest that the two major CSN3 3'UTR polymorphisms in Chinese Holstein cows cause significant changes in CSN3 gene expression, CSN3 protein expression, and bta-miR-708 binding ability but no significant alterations in macroscopic DHI data. Therefore, CSN3 3'UTR polymorphisms should be investigated further. [ABSTRACT FROM AUTHOR]