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Liner is an important component connecting brake oil pipe and brake in automobile brake system, and the oversize of inner diameter will seriously affect the brake performance of vehicles. Aiming at the problems of low efficiency, poor accuracy and inconsistent detection standards in the manual measurement of liner inner diameter, a method for measuring liner inner diameter based on machine vision was proposed. The inner diameter of liner was preprocessed and located by using bilateral filtering, improved Otsu threshold method and morphological method. An improved Canny edge detection operator was used to extract the inner diameter contour points, and the least square method was used to fit the circle based on Tukey weight function to calculate the inner diameter size. The experimental verification shows that the measurement error value of the detection algorithm is within ± 0.01 mm, the measurement accuracy is 98.9%, the missing rate is 0, and the passing rate is 1.1%, which can meet the actual measurement requirements of enterprises. [ABSTRACT FROM AUTHOR]

The rheological properties of the filling slurry have an important influence on the pipeline transportation and the strength of the filling body, the relationship between the yield stress, apparent viscosity and the mass concentration, the amount of waste rock and the cement sand ratio is studied. The results show that the yield stress increases with the mass concentration, and will increase significantly when mass concentration is higher than 70%. When the mass concentration is 72%, the initial apparent viscosity of backfill slurry can be increased by blending appropriate content of waste rock in, and when the content of waste rock is more than 10%, the initial apparent viscosity will gradually decrease; when the concentration is less than 66%, content of waste rock has little effect on the initial apparent viscosity; when the content of waste rock is 0, the larger the cement sand ratio, the greater the yield stress; when the content of waste rock is 10%, 20%, the cement sand ratio has little effect on the yield stress. When the content of waste rock is 30% and 40%, the larger the cement sand ratio, the smaller the yield stress; the most significant effect factor is the mass concentration. [ABSTRACT FROM AUTHOR]

Glaucoma is one of the most common optic neuropathies, featuring progressive retinal ganglion cell damage and visual field loss (Tham et al., 2014; Xu et al., 2020). Currently, the only effective treatment for this condition is the reduction of intraocular pressure (IOP) (Palmberg, 2001; Heijl et al., 2002). Canaloplasty is a proven bleb-independent surgery with good efficacy and safety profiles in primary open-angle glaucoma (POAG) (Gołaszewska et al., 2021). However, early transient postoperative IOP elevation has been reported in up to 30% of cases (Riva et al., 2019), similar to that commonly observed in other internal drainage glaucoma surgeries such as implantation using iStent (0%-21.0%), CyPass (10.8%), and Hydrus (4.8%-6.5%) (Lavia et al., 2017). This complication may be a predictor of poor reserve in the outflow system and is potentially associated with surgical failure. Nonetheless, the exact pathophysiology of glaucoma remains unknown, and studies clarifying the risk factors for postoperative IOP elevation have been scarce.

Objective: To establish the canine model of new-onset atrial fibrillation (AF) after acute myocardial infarction (AMI), and explore the relationship between new-onset AF and sympathetic neural remodeling in this model., Methods: Twenty four adult mongrel dogs were randomly divided into 4 groups by applying random number table. Group A (n=6): ligate the left circumflex artery (LCX). Group B (n=6): ligate the LCX and right atrial anterior artery and right atrial middle artery. Group C (n=6): ligate left anterior descending artery.Group D (n=6): sham operation.Sequential electrophysiology study was performed in all dogs to determine the AF induction rate, AF duration, effective refractory period (ERP), the density of tyrosine hydroxylase (TH) and norepinephrine transporter (NET) before AMI or sham operation, and at 30 min, 2 hours and 4 hours after AMI or sham operation., Results: (1) The highest AF induction rate of right atrium and left auricle was 96.7%(58/60) and 95.0%(57/60) in group B, 81.7%(49/60) and 38.3%(23/60) in group A, 28.3%(17/60) and 35.0%(21/60) in group C, 20.0%(12/60) and 33.3%(20/60) in group D. (2) At 4 hours after AMI, AF duration was significantly prolonged in group B(193.50±54.67) s, compared with group A(53.83±9.37) s, group C(45.00±19.50) s, and group D(16.67±4.50) s (all P<0.05). (3) In group B, the ERP of AF was prolonged at 30 minutes after AMI and shortened at 2 hours and 4 hours after AMI compared with baseline level(all P<0.05). (4) The TH density of left atrium ((3 485±694) µm2/mm2) and left auricle((2 645±454) µm2/mm2) in group A and the TH density of left atrium ((7 873±1159) µm2/mm2) and left auricle((3 070±605) µm2/mm2) in group B were significantly higher than those in group C ((1 474±475) µm2/mm2, (1 177±277) µm2/mm2) and group D ((678±206) µm2/mm2, (489±125) µm2/mm2) (all P<0.05), and the TH density of right atrium and right auricle in group B were higher than group A (all P<0.05). The NET density of left atrium((476±75) µm2/mm2) and left auricle ((414±52) µm2/mm2) in group A and the NET density of left atrium((527±81) µm2/mm2) and left auricle((429±85) µm2/mm2) in group B were lower than that in group C ((1 044±105) µm2/mm2, (867±67) µm2/mm2) and group D ((1 438±60) µm2/mm2, (1 027±119) µm2/mm2) (all P<0.05)., Conclusions: Ligating the LCX, right atrial anterior artery and right atrial middle artery at the same time can significantly increase the success rate in establishing the canine model of new-onset atrial fibrillation after acute myocardial infarction and can also increase the AF duration.Cardiac sympathetic remodeling after acute myocardial infarction is associated with induction and duration of AF.

Objective: Detect the relationship between TPM1 gene mutations and dilated cardiomyopathy (DCM) of Kazaks and Hans in Xinjiang., Methods: TPM1 gene was screened from 31 family members in a Kazak family with familiar DCM (FDCM), 100 patients with idiopathic DCM (IDCM, 50 Kazaks and 50 Hans), and in 100 healthy controls (50 Kazaks and 50 Hans). All the samples were the inpatients or outpatients of First Affiliated Hospital of Xinjiang University from 2012 to 2014. PCR was used to amplify 9 exons and nearby introns of the TPM1 gene. The amplified products were sequenced and compared with the standard sequence with CHROMAS software and BLAST software in Pubmed to identify mutation sites. The relationship between TPM1 gene mutations in the Kazak IDCM and healthy volunteers, between Han and Kazak IDCM and healthy volunteers was analyzed. Tropomyosin was qualitatively and quantitatively detected by ELISA in all subjects., Results: A novel variant (c.524 G > T) was identified in two FDCM patients at exon 3, this mutation caused an amino acid substitution, Gln111His. The FDCM, IDCM from Kazak and Han, healthy volunteers from Kazak and Han were founded a rs1071646 (c.644C > A, Ala151Ala). There was a significant difference in the genotype distribution (χ(2) = 13.36, P = 0.001) and allele frequency (χ(2) = 10.25, P = 0.001) between Kazaks with IDCM and Kazak controls of rs1071646, while these parameters were similar between Han IDCM patients and Han controls (all P > 0.05). The tropomyosin content of Kazak and Han IDCM patients were significantly lower than Kazak and Han controls ((1 764.2 ± 350.9) ng/L vs. (2 369.7 ± 345.9) ng/L, P = 0.001)., Conclusion: TPM1 gene of rs1071646 polymorphism is a possible independent risk factor for IDCM in Kazaks but not Han Chinese.

Objective: To assess the association of VKORC1 gene -1639G/A polymorphism with atrial fibrillation (AF) in ethnic Uygurs and Hans from Xinjiang., Methods: The above polymorphism was detected among 100 Uygur and 102 Han AF patients and 103 Uygur and 111 Han subjects that have no AF with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method., Results: A statistically significant difference was detected between the patient and control groups of Uygur origin in terms of genotypic and allelic frequencies (P<0.05). Logistic regression analysis also indicated the -1639G/A polymorphism as an independent risk factor for AF in Uygur population (OR=2.085, 95% CI: 1.067-4.072, P=0.031). No similar statistical difference was found between the patient and control groups of Han origin (P>0.05)., Conclusion: The -1639G/A polymorphism of VKORC1 gene is associated with AF in the Uygur population but not in Hans.