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Laser additive manufacturing （LAM） enables the integrated direct formation of high-performance metallic components with complex geometry. However， the non-uniform distribution of temperature gradients， in-situ heat treatment effects， non-equilibrium solid phase transformations， and heterogeneous microstructure during the process result in intricate residual stresses that significantly affect the quality and overall performance. A comprehensive review of residual stress in LAM by introducing its fundamental definition and classification is provided in this paper. Furthermore， the particularity， formation mechanisms， characterization methods， and regulation techniques associated with residual stress in LAM is systematically reviewed. The subsequent sections introduce various characterization methods for residual stress in LAM components， along with their respective characteristics. Additionally， the applicability， advantages， and disadvantages of each method are presented. Furthermore， the methods for controlling residual stress can be categorized into post-treatment control and in-situ treatment control. Finally， the joint effect of different types of residual stress should be considered in the study of the cause and evolution mechanism of residual stress in LAM. The characterization method of residual stress should be integrated with various methods to facilitate mutual verification. To mitigate the impact of stress concentration on the printing process and resultant quality， as well as minimize the influence of post-processing stress on part accuracy， it is imperative to investigate in-situ control methods for residual stress and explore real-time online monitoring techniques for LAM.

In order to improve the recognition rate and location accuracy of circular targets under the conditions of long-distance and large detection angle, a circular target stability detection method was proposed based on deep learning image super-resolution. The mutt-angle and multi-distance image sets were constructed through a hybrid data set of real images and synthetic images, the pixel loss and perceptual loss were used to improve the loss function of image super-resolution model, so the super-resolution reconstruction of images might be realized and the image details of target contours might be enriched. By using the pretrained super-resolution model, the images were reconstructed. Finally, traditional detection algorithm was used to recognize and locate the circular targets. The experimental results show that the circular target recognition rate is increased by 40%, and the target location accuracy is increased by 8.47%. [ABSTRACT FROM AUTHOR]

To investigate the association of DNA polymorphisms in CYP11B2 and CYP11Bl loci with the risk of aldosterone-producing adenoma (APA). Methods We used the real-time PCR TaqMan-MGB probe to detect the single nucleotide polymorphism ( SNP) of CYP11B2 gene rs5301, rs6471570 and CYP11B2 gene rs3802228, rs3802230, rs4545, rs4546, and rs6433 loci in the peripheral blood of 80 patients with APA (APA group) and 101 healthy controls (control group). SNPassoc 1. 9-2 and Haplo stats 2. 17. 0 software were performed to analyse the correlation of the CYP11B2 and CYP11B1 haplotype and genotype with the risk of APA. Results The frequencies of the A allele of rs5301, A allele of rs3802228, and Gallele of rs6433 were higher in the APA group than in the control group (all P < 0. 05). After we adjusted the sex, age and BMI, the frequency of the AG genotype of rs4545 in the APA group was less than that of the control group (P < 0. 05). The haplotype analysis showed that frequencies of GAACAAC and GCGAAGT were lower than those of the control group (OR= 0. 73, 95% CI= 0. 57-0. 93; OR= 0. 81, 95% CI 0. 69-0. 95). Conclusions CYP11B2 and CYP1B1 gene polymorphisms are associated with the risk of APA. The polymorphism rs4545 locus of the CYP11B2 gene is associated with APA population, and APA is negatively correlated with haplotype GAACAAC and GCGAAGT. [ABSTRACT FROM AUTHOR]

In order to explore the microbial communities and functions in distinct environments of acid mine drainage (AMD) ecosystem and fully comprehend the patterns of AMD formation and development, high-throughput sequencing technology was used to study the prokaryotic community composition in AMD puddles and surrounding rills in a mining area in Mengzi, Yunnan Province, China. By combining with physicochemical properties of the samples, we distinguished the key factors affecting the community structure and analyzed the environmental functions of the microflora. We discovered that the main phyla in AMD puddles were Euryarchaeota, Proteobacteria (including the class α-, γ- and δ-Proteobacteria), Nitrospirae, Firmicutes, Actinobacteria, and Acidobacteria. Community structure of the AMD puddles apparently differed from that of the surrounding rills. Microbial diversity was significantly positively correlated with pH, whereas the relative abundance of Thermoplasmata was negatively correlated with pH and this class might play a predominant role in community structure. There was high relative abundance of the genus Ferroplasma (6.60%-86.34%) in different samples of AMD puddles. Acidithiobacillus spp. were the major iron- and/or sulfur-oxidizing bacteria in AMD solutions and sediments, whereas relative abundance of the obligate iron-oxidizer Leptospirillum spp. was lower, and Ferrovum spp. were almost only present in the AMD solutions. In addition, acidophilic or acid-tolerant heterotrophic bacteria were widely distributed in the AMD solutions and sediments, which might promote the growth of iron- and/or sulfur-oxidizers and catalyze the oxidative/reductive dissolution of metal ores. Our results suggested that pH significantly impacted the microbial community structure of AMD environment by affecting the microbial diversity and microflora distribution.

Objective: To analyze the effectiveness of fast track protocol of geriatric intertrochanteric fracture on operative waiting time, operation time, perioperative blood loss, providing data support for clinical therapy., Methods: The clinical data of 240 elderly patients with intertrochanteric fracture admitted between January 2015 and December 2018 were retrospectively analyzed. They were divided into traditional protocol group (148 cases, group A) and fast track group (92 cases, group B). All patients were treated with closed reduction intramedullary nail (proximal femoral nail antirotation) surgery. There was no significant difference in gender, age, sides, fracture classification, fracture type, complications, the proportion of patients with more than 3 kinds of medical diseases, and the time from injury to admission between the two groups ( P >0.05). Analysis index included operative waiting time (hospitalization to operation time), operation time, percentage of operation performing in 48 and 72 hours, percentage of transfusion, changes of hematocrit (Hct) at different stage (admission, operation day, and postoperative 1, 3 days), blood loss by fracture and cephalomedullary nail, intraoperative dominant blood loss, total blood loss in perioperative period were recorded and compared., Results: The operative waiting time, operation time, Hct on operation day and postoperative 3 days, blood loss by fracture, transfusion volume, and total blood loss in perioperative period in group B were significantly less than those in group A ( P <0.05), and the percentage of operation performing in 48 and 72 hours in group B were significantly higher than those in group A ( P <0.05). There was no signifcant difference in Hct on admission and postoperative 1 day, intraoperative dominant blood loss, percentage of transfusion, blood loss by cephalomedullary nail between the two groups ( P >0.05)., Conclusion: Fast track can shorten the operative waiting time of geriatric intertrochanteric fracture, reduce the blood loss by fracture, total blood loss in perioperative period, and transfusion volume. Early operation is conducive to improve the anemia status of patients during perioperative period.

Objective: To develop an anti-hepatitis E virus (anti-HEV) IgG chemiluminescence assay kit and assess its clinical application., Methods: The HEV recombinant antigen was used as coating antigen, horseradish peroxidase (HRP)-conjugated monoclonal anti-human IgG as the secondary antibody, and the luminol chemiluminescent reaction system as a substrate. The sensitivity, specificity, precision and other technical indicators of the kit were evaluated using the HEV national reference product, and a contrast experiment was conducted on 1012 serum samples by the kit developed in this research and a commercialized anti-HEV IgG chemiluminescence assay kit., Results: The sensitivity, specificity, precision and stability of all the three batches of kit reached national standard. In the detection of 1012 clinical serum samples, the positive coincidence rate of both kits was 97.4%, the negative coincidence rate was 99.4%, and the total coincidence rate reached 98.4%., Conclusion: An anti-HEV IgG chemiluminescence assay kit has been successfully developed. The kit is of high sensitivity and specificity, easy to operate. It is applicable to the clinical diagnosis and epidemiological survey of HEV infection.