An Innovative Collaborative Design of Shape and Performance for Super-High-Contact-Ratio Spiral Bevel Gear

Yan-Ming Mu,Xiang-ying Hou,Si-wei Yang,Xue-Ming He 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.5

For upgrading the transmission performance of spiral bevel gear and extending the time between overhauls of the helicopter reducer, an innovative multi-objective collaborative optimization strategy of shape and performance is put up for the super-high-contact-ratio spiral bevel gear transmission with the contact path along tooth width based on ease-off. Firstly, according to the preset contact path curve along tooth width and the symmetrical transmission error curve, the pinion optimal surface satisfying the preset functions is obtained based on ease-off. Secondly, based on the basic principles of simulated annealing and gravitational search, the simulated annealing-gravity search cooperative intelligent optimization algorithm is set up for the calculation of the multi-objective collaborative optimization model of the spiral bevel gear transmission, and the modified surface of pinion satisfying the function requirements is obtained based on the collaborative optimization of shape and performance. Finally, combined with the tooth contact analysis method, meshing impact analysis method and dynamic analysis method, the loaded transmission error, meshing impact and dynamic performance of the super-high-contact-ratio spiral bevel gear transmissions are discussed. The simulation result shows the contact path of the collaborative designed spiral bevel gear transmission is along the tooth width, and the contact ratio reaches the maximum. The loaded transmission error, meshing impact, dynamic load factor and root mean square of vibration acceleration of the collaborative design spiral bevel gear transmission are all smaller than the original design and optimized design spiral bevel gear transmissions. The feasibility of the innovative multi-objective collaborative optimization strategy of shape and performance for the spiral bevel gear is verified, and the super-high-contact-ratio design can greatly cut down the contact vibration of the spiral bevel gear transmissions and better the helicopter’s performance.

Adaptive Detection of a Moving Target Undergoing Illumination Changes against a Dynamic Background

Mu Lu,Yang Gao,Ming Zhu 한국광학회 2016 Current Optics and Photonics Vol.20 No.6

A detection algorithm, based on the combined local-global (CLG) optical-flow model and Gaussianpyramid for a moving target appearing against a dynamic background, can compensate for the inadaptabilityof the classic Horn–Schunck algorithm to illumination changes and reduce the number of neededcalculations. Incorporating the hypothesis of gradient conservation into the traditional CLG optical-flowmodel and combining structure and texture decomposition enable this algorithm to minimize the impactof illumination changes on optical-flow estimates. Further, calculating optical-flow with the Gaussianpyramid by layers and computing optical-flow at other points using an optical-flow iterative with highergray-level points together reduce the number of calculations required to improve detection efficiency. Finally, this proposed method achieves the detection of a moving target against a dynamic background,according to the background motion vector determined by the displacement and magnitude of theoptical-flow. Simulation results indicate that this algorithm, in comparison to the traditional Horn-Schunckoptical-flow algorithm, accurately detects a moving target undergoing illumination changes against adynamic background and simultaneously demonstrates a significant reduction in the number of computationsneeded to improve detection efficiency.

A comparative experimental study on the cross-plane thermal conductivities of nano-constructed Sb2Te3/(Cu, Ag, Au, Pt) thermoelectric multilayer thin films

Yang Gang,Pan Jiahui,Fu Xuecheng,Hu Zhiyu,Wang Ying,Wu Zhimao,Mu Erzhen,Yan Xue-Jun,Lu Ming-Hui 나노기술연구협의회 2018 Nano Convergence Vol.5 No.22

Thermoelectric multilayer thin films used in nanoscale energy conversion have been receiving increasing attention in both academic research and industrial applications. Thermal transport across multilayer interface plays a key role in improving thermoelectric conversion efficiency. In this study, the cross-plane thermal conductivities of nano-constructed Sb2Te3/(Cu, Ag, Au, Pt) thermoelectric multilayer thin films have been measured using time-domain thermoreflectance method. The interface morphology features of multilayer thin film samples were characterized by using scanning and transmission electron microscopes. The effects of interface microstructure on the cross-plane thermal conductivities of the multilayer thin films have been extensively examined and the thermal transfer mechanism has been explored. The results indicated that electron–phonon coupling occurred at the semiconductor/metal interface that strongly affected the cross-plane thermal conductivity. By appropriately optimizing the period thickness of the metal layer, the cross-plane thermal conductivity can be effectively reduced, thereby improving the thermoelectric conversion efficiency. This work presents both experimental and theoretical understanding of the thermal transport properties of Sb2Te3/metal multilayer thin film junctions with important implications for exploring a novel approach to improving the thermoelectric conversion efficiency. Introduction Thermoelectric multilayer thin films used in nanoscale energy conversion have been receiving increasing attention in both academic research and industrial applications. Thermal transport across multilayer interface plays a key role in improving thermoelectric conversion efficiency. In this study, the cross-plane thermal conductivities of nano-constructed Sb2Te3/(Cu, Ag, Au, Pt) thermoelectric multilayer thin films have been measured using time-domain thermoreflectance method. The interface morphology features of multilayer thin film samples were characterized by using scanning and transmission electron microscopes. The effects of interface microstructure on the cross-plane thermal conductivities of the multilayer thin films have been extensively examined and the thermal transfer mechanism has been explored. The results indicated that electron–phonon coupling occurred at the semiconductor/metal interface that strongly affected the cross-plane thermal conductivity. By appropriately optimizing the period thickness of the metal layer, the cross-plane thermal conductivity can be effectively reduced, thereby improving the thermoelectric conversion efficiency. This work presents both experimental and theoretical understanding of the thermal transport properties of Sb2Te3/metal multilayer thin film junctions with important implications for exploring a novel approach to improving the thermoelectric conversion efficiency. Introduction

Comparative analysis of metabolites and in vitro hypoglycemic activity of Taiwanofungus camphoratus cultured using various methods

Ming YongFei,Li Yin,Chu JianZhi,Zhou XiaoShuang,Huang YuXuan,Yang ShuDe,Mu YueJun,Wang Lin,Zhang Rui,Cheng XianHao 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

Taiwanofungus camphoratus has attracted much attention because it can abundantly produce various active substances that exhibit blood-sugar lowering, immunity improving, and antioxidant properties. Currently, T. camphoratus is cultured using four main methods: cutting wood culture, solid-state fermentation, submerged fermentation, and dish culture. T. camphoratus produces different metabolites under different culture methods. In this study, nontargeted metabolomics was used to compare the metabolites of T. camphoratus produced under these four culture methods. Principal component analysis and supervised partial least squares-discriminant analysis were used to analyze the differences in the metabolites. Moreover, in vitro hypoglycemic activity of T. camphoratus extracts produced under four culture methods was compared by assessing their ability to inhibit the activity of α-glucosidase, α-amylase, and sucrase. A total of 186 metabolites were identified. In total, 127 metabolites were common under the four culture methods. Under solid-state fermentation, submerged fermentation, and cutting wood culture, 12, 1, and 4 metabolites were unique, respectively. The differential metabolites produced by T. camphoratus under four culture methods were mainly triterpenoids, phenolic compounds, and fatty acid compounds. α-glucosidase, α-amylase, and sucrase activity inhibition was the best using T. camphoratus extract obtained under cutting wood culture; the inhibition rates were 55.97%, 51.96%, and 78.02%, respectively, which were comparable to those exhibited by 0.001, 3, and 12 mg/mL acarbose (positive control). The metabolites produced by T. camphoratus and α-glucosidase, α-amylase, and sucrase inhibitory activities were different under the four culture methods. Cutting wood culture exhibited the best enzyme inhibitory activity. This study provided a theoretical basis for further use and development of various culture methods for the rational production of active metabolites of T. camphoratus.

Gastrin stimulates pancreatic cancer cell directional migration by activating the Gα12/13–RhoA–ROCK signaling pathway

Ganggang Mu,Qianshan Ding,Hongyan Li,Li Zhang,Lingli Zhang,Ke He,Lu Wu,Yunchao Deng,Dongmei Yang,Lianlian Wu,Ming Xu,Jie Zhou,Honggang Yu 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

The mechanism by which gastrin promotes pancreatic cancer cell metastasis is unclear. The process of directing polarized cancer cells toward the extracellular matrix is principally required for invasion and distant metastasis; however, whether gastrin can induce this process and its underlying mechanism remain to be elucidated. In this study, we found that gastrin-induced phosphorylation of paxillin at tyrosine 31/118 and RhoA activation as well as promoted the metastasis of PANC-1 cancer cells. Depletion of Gα12 and Gα13 inhibited the phosphorylation of paxillin and downstream activation of GTP-RhoA, blocked the formation and aggregation of focal adhesions and facilitated polarization of actin filaments induced by gastrin. Suppression of RhoA and ROCK also exhibited identical results. Selective inhibition of the CCKBR–Gα12/13–RhoA–ROCK signaling pathway blocked the reoriented localization of the Golgi apparatus at the leading edge of migrated cancer cells. YM022 and Y-27632 significantly suppressed hepatic metastasis of orthotic pancreatic tumors induced by gastrin in vivo. Collectively, we demonstrate that gastrin promotes Golgi reorientation and directional polarization of pancreatic cancer cells by activation of paxillin via the CCKBR–Gα12/13–RhoA–ROCK signal pathway.

Seroprevalence of Toxoplasma gondii Infection in Police Dogs in Shenyang, Northeastern China

Cheng-Wu Liu,Na Yang,Jian-Bin He,Ming-Yang Mu,Min Yang,Ning Sun,Hong-Kui Li 대한기생충학열대의학회 2013 The Korean Journal of Parasitology Vol.51 No.5

Molecular and Biochemical Characterization of a Novel Xylanase from Massilia sp. RBM26 Isolated from the Feces of Rhinopithecus bieti

( Bo Xu ),( Li Ming Dai ),( Jun Jun Li ),( Meng Deng ),( Hua Biao Miao ),( Jun Pei Zhou ),( Yue Lin Mu ),( Qian Wu ),( Xiang Hua Tang ),( Yun Juan Yang ),( Jun Mei Ding ),( Nan Yu Han ),( Zun Xi Huang 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.1

Xylanases sourced from different bacteria have significantly different enzymatic properties. Therefore, studying xylanases from different bacteria is important to their applications in different fields. A potential xylanase degradation gene in Massilia was recently discovered through genomic sequencing. However, its xylanase activity remains unexplored. This paper is the first to report a xylanase (XynRBM26) belonging to the glycosyl hydrolase family (GH10) from the genus Massilia. The gene encodes a 383-residue polypeptide (XynRBM26) with the highest identity of 62% with the endoxylanase from uncultured bacterium BLR13. The XynRBM26 expressed in Escherichia coli BL21 is a monomer with a molecular mass of 45.0 kDa. According to enzymatic characteristic analysis, pH 5.5 is the most appropriate for XynRBM26, which could maintain more than 90% activity between pH 5.0 and 8.0. Moreover, XynRBM26 is stable at 37°C and could maintain at least 96% activity after being placed at 37°C for 1 h. This paper is the first to report that GH10 xylanase in an animal gastrointestinal tract (GIT) has salt tolerance, which could maintain 86% activity in 5 M NaCl. Under the optimum conditions, Km, Vmax, and kcat of XynRBM26 to beechwood xylan are 9.49 mg/ml, 65.79 μmol/min/mg, and 47.34 /sec, respectively. Considering that XynRBM26 comes from an animal GIT, this xylanase has potential application in feedstuff. Moreover, XynRBM26 is applicable to high-salt food and seafood processing, as well as other high-salt environmental biotechnological fields, because of its high catalytic activity in high-concentration NaCl.

CD64 Expression Is Increased in Patients with Severe Acute Pancreatitis: Clinical Significance

( Hao Zhang ),( Xian Long Ling ),( Yu Yun Wu ),( Mu Han Lu ),( Hong Guo ),( Peng Bin Zhang ),( Xiao Yan Zhao ),( Shi Ming Yang ) 대한소화기학회 2014 Gut and Liver Vol.8 No.4

Background/Aims: Upregulated CD64 expression on neutrophils is the most useful marker for acute bacterial infections and systemic inflammation. However, it is unknown whether CD64 is involved in the pathogenesis of acute pancreatitis (AP). This study was designed to determine whether CD64 is implicated in severe acute pancreatitis (SAP), and thus, is a suitable marker for SAP. Methods: SAP was induced in rats with an intraperitoneal injection of L-arginine. CD64 expression in the rat pancreas was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Additionally, the CD64 mRNA expression in peripheral blood leukocytes from 21 patients with mild acute pancreatitis (MAP) and 10 patients with SAP was investigated at the time of admission and during remission by qRT-PCR. Results: CD64 mRNA and protein expression in the pancreas was significantly higher in rats with SAP, compared to the controls. The CD64 expression was higher in the patients with SAP than in the patients with MAP. During remission, CD64 mRNA decreased in both the MAP and SAP patients. The area under the curve of CD64 expression for the detection of SAP was superior to both the Ranson and the Acute Physiology and Chronic Health Evaluation II scores. Conclusions: The CD64 level was significantly increased in correlation with the disease severity in SAP and may act as a useful marker for predicting the development of SAP. (Gut Liver 2014;8:445-451)

Hookworm Infection: A Neglected Cause of Overt Obscure Gastrointestinal Bleeding

Kun-Yan Wei,Qiong Yan,Bo Tang,Shi-Ming Yang,Peng-Bing Zhang,Ming-Ming Deng,Mu-Han Lu 대한기생충학열대의학회 2017 The Korean Journal of Parasitology Vol.55 No.4

Clinical Value of Eukaryotic Elongation Factor 2 (eEF2) in Non-small Cell Lung Cancer Patients

Sun, Hong-Gang,Dong, Xue-Jun,Lu, Tao,Yang, Ming-Feng,Wang, Xing-Mu Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Background: The purpose of this study was to evaluate a new type of tumor biomarker, eukaryotic elongation factor 2 (eEF2), in serum for the early diagnosis, confirmative diagnosis as well as assessment of treatment of non-small cell lung cancer (NSCLC). Methods: 130 patients with NSCLC and 50 healthy individuals undergoing physical examination in our hospital provided the observation and healthy control groups. An enzyme linked immune sorbent assay (ELISA) method was applied to determine serum eEF2 levels. Serum neuron specific enolase (NSE) and squamous cell carcinoma antigen (SCC) levels in the observation group were assessed with an automatic biochemical analyzer. Results: The median levels of eEF2 in the serum of NSCLC patients was found to be significantly higher than the healthy control group (p < 0.01) and it was markedly higher in stages III, IV than stages I, II (p < 0.05). eEF2 was higher with tumor size ${\geq}2$ cm than <2 cm (P< 0.01). Furthermore, two weeks after surgery patients showed a significant trend for eEF2 decrease (p < 0.05). Conclusions: The eukaryotic elongation factor 2 (eEF2) has certain clinical values for early diagnosis, verification, and prognosis as well as classification of lung cancer patients.