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Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) has been widely used in the determination of Nb and Ta, but its low sensitivity and high detection limits cannot meet the analysis requirement of low content Nb and Ta in ores and metallurgical samples. The sensitizing effect of many organic reagents was optimized in the ICP-AES determination. The results show that ethanol is the best sensitizer for determination of Nb and Ta after the samples were decomposed by open acid-solution with HF-HNO3-H2 SO4 mixture. When the concentration of ethanol reaches 6%, the sensitivities of Nb (292. 781 nm) and Ta (240. 063 nm) have increases of 180. 5% and 265. 5%, respectively. Moreover, the detection limits of Nb and Ta were reduced from 5. 85 to 3.22 μg/g and from 10. 65 to 5. 03 μg/g, respectively. The recoveres of Nb2 O5 and Ta2 O5 were 97. 7% -01.9% and 96.8% -97. 2%, respectively. The precision of this method was less than 6%. The method is suitable for the simultaneous determination of low and high contents of Nb and Ta, and is particularly suitable for determining Nb and Ta in ore concentrates, medium ores and the tailings of metallurgical samples from the same batch, which overcomes the bad agreement of recovery between ICP-AES and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). [ABSTRACT FROM AUTHOR]

In accordance with the working environment and loading features of the balance displayed in the airdrop test, the design load and the balance structure are defined. Safety factor of the spring is calculated in the every extreme overloading condition specific to the practical use of the balance. Stress field of the balance is deduced through finite element analysis, and the stress distribution of the whole balance is obtained. The results are tested further, which offer theoretic support for the final structure design of the balance. [ABSTRACT FROM AUTHOR]

Objective To provide reference for controlling or delaying the decline of pulmonary ventilation function in male pneumoconiosis patients by studying associations of serum albumin levels with the risk of severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients. Methods A retrospective cohort design was adopted in this study. Male pneumoconiosis patients who were hospitalized in West China Fourth Hospital from January 2012 to December 2021 and did not have pulmonary ventilation dysfunction at baseline were selected as the study objects. Cox proportional hazard regression models were used to calculate HRs and 95% CIs to evaluate the association of baseline serum albumin levels and the risk of severe or very severe pulmonary ventilation dysfunction. Restricted cubic spline plot was used to explore whether there was a dose-response relationship between baseline serum albumin concentrations and the risk of severe or very severe pulmonary ventilation dysfunction. Results A total of 746 subjects were included in this study. Fully adjusted model results of Cox proportional hazard regression analysis showed that male pneumoconiosis patients with serum albumin higher than 40.8 g/L had a reduced risk of severe or very severe pulmonary ventilation dysfunction compared with male pneumoconiosis patients with serum albumin lower than 34.4g/L (HR = 0.660, 95% CI: 0.439-0.992). The restricted cubic spline figure showed that the risk of severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients gradually decreased with the gradual increase of serum albumin concentrations and there was a linear negative relationship between baseline serum albumin concentrations and the incidence risk of severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients (P < 0.05). Conclusion Higher serum albumin is a protective factor for severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients and maintaining the serum albumin concentrations above 40.8 g/L can reduce the risk of severe or very severe pulmonary ventilation dysfunction. [ABSTRACT FROM AUTHOR]

To reduce the rejection rate of products, a novel single-piece heavy-load force sensor with a full-scale load of 150 t and a working frequency of 10 Hz is designed, manufactured and evaluated for the dynamic impact force measurement of the punch. The confined space of the punch holder limits the size of the fabricated sensor at φ166 mm × 45 mm. The sensor is characterized by an integrated fixture with four bearing carriers and one strain beam, which can ensure both strong stiffness and high sensitivity for the sensor simultaneously. A universal hydraulic machine with full-scale 300 t is employed to accomplish static calibration. The results show that linear calibration slopes for the sensor is within 2%. Site test is then performed for further verifying sensor performance. [ABSTRACT FROM AUTHOR]

Objective To construct a deep learning model based on multi -task learning to assist clinicians in differential diagnosis and staging of pneumoconiosis. Methods The digital chest radiographs of 3 600 patients from an occupational disease hospital in Sichuan Province from 2011 to 2022 were collected, and the full convolution neural network (UNet) was used to segment the lung field. Based on multi-task learning, the multi-task model was constructed using the correlation between tasks. The multi -task model was pre -trained on the ChestX -ray14 dataset, whose backbone network was DenseNetl21, and two classifiers were added behind the backbone network. Paired t-test was used to compare the differences in accuracy, precision, sensitivity, and Fl scores between single-task model and multi-task model. Results The test set results showed that the differential diagnosis and diagnostic staging performance of the single-task model was about 90% and 77%, respectively. The differential diagnosis and diagnosis staging performance of the multi-task model was about 94% and 86%, which was higher than that of the single-task model about 4% and 9%, respectively. The difference between the evaluation indexes was statistically significant (P < 0.05). Conclusion The multi-task model has more advantages than the single-task model and can effectively realize the differential diagnosis and accurate staging of pneumoconiosis and pulmonary tuberculosis. [ABSTRACT FROM AUTHOR]

Objective·To explore microRNAs (miRNAs) as biomarkers of polycystic ovary syndrome (PCOS) and the biological significance in the pathogenesis of PCOS. Methods·Five patients with PCOS from January 2019 to October 2019 in Renji Hospital, Shanghai Jiao Tong University School of Medicine were selected as the observation group, and 5 healthy women were selected as the control group. Granulosa cells from 2 groups were collected and RNA was extracted by TRIzol method. TruSeq Small RNA Library Prep Kit was used to construct miRNA-Seq library. After the quality inspection of the library, NextSeq500 was used for high-throughput sequencing. Bioinformatics data analysis was performed on the sequencing results. RT-qPCR was used to verify the differential expression of candidate miRNA markers. Results·We finally got 20 differentially expressed miRNAs (all P<0.05). Among them, miR-196a-5p, miR-10a-5p and miR-451a were significantly up-regulated, while miR-877-5p and miR-2355-5p were significantly down-regulated. These differentially expressed miRNAs and their target genes may be involved in the transcriptional regulation mechanism of PCOS occurrence and development. Conclusion·Differentially expressed miRNAs have potential as PCOS biomarkers and are involved in the occurrence and development of PCOS. [ABSTRACT FROM AUTHOR]

Objective To evaluate the association between SNP-1082G/A (rs1800896), -819C/T (rs1800871), -592C/A (rs1800872) polymorphisms in the IL-10 promoter region and HCV chronic infection in Han nationality in Yunnan province. Methods 379 HCV chronic infectious patients and 364 healthy individuals of Han nationality in Yunnan province were recruited. Three single nucleotide polymorphisms (SNPs) in the IL-10 promoter region, -1082G/A (rs1800896), -819C/T (rs1800871) and -592C/A (rs1800872) were determined by real-time TaqMan polymerase chain reaction. The haplotypes were constructed and the association between these three SNPs and haplotypes and HCV chronic infection were analyzed. Results The frequencies of SNPs -1082G/A (rs1800896), -819C/T (rs1800871), -592C/A (rs1800872) in the IL-10 promoter region between hepatitis C virus (HCV) chronic infectious patients and the healthy controls were not statistically significant (> 0.05) at both allele and genotypes levels. The frequencies of haplotypes constructed by SNP-1082G/A (rs1800896), -819C/T (rs1800871) and -592C/A (rs1800872) also showed no significant difference (> 0.05). Conclusion SNPs -1082G/A (rs1800896), -819C/T (rs1800871), -592C/A (rs1800872) in the IL-10 promoter region were not associated with HCV chronic infection in the Han nationality in Yunnan province. [ABSTRACT FROM AUTHOR]