A new analytical ICCE and force prediction model for wide-row machining of free-form surface

Minglong Guo,Zhaocheng Wei,Jia Wang,Minjie Wang,Xiaoyu Wang,Shengxian Liu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.1

Cutting force is the most intuitive reflection of various influencing factors in the milling process, which is important for improving machining quality and efficiency. For the widerow milling with flat-end mill of free-form surface, an analytical in-cut cutting edge (ICCE) algorithm is studied in detail, and overall cutting force model is further constructed. The cutter location points along tool path are discretized into small oblique planes. Taking the oblique plane machining as the new object, the relative position of flat-end mill and workpiece in five-axis machining is defined parametrically. By constructing a semi-enclosed space in which the cutting edge participates in cutting, the ICCE is directly obtained. By analyzing the cutting force of oblique plane, the cutting force model of free-form surface can be established by spatial coordinate transformation. The simulation and experiment have demonstrated the correctness and effectiveness of the proposed ICCE algorithm and force prediction model.

A Large-Scale, Stratified Genetic Analysis of the Major Histocompatibility Complex Region in Early- and Late- Onset Psoriasis in China

( Yi Zhou ),( Minglong Cai ),( Yujun Sheng ),( Xuejun Zhang ) 대한피부과학회 2021 Annals of Dermatology Vol.33 No.1

Background: Psoriasis vulgaris is a chronic inflammatory skin disease which occur at any age. It can be clinically classified into two age-onset subtypes: early-onset psoriasis (EOP; <40 years) and late-onset psoriasis (LOP; ≥40 years). More evidence showed EOP and LOP have different genetic architecture, notably the risk allele human leukocyte antigen (HLA)-C*06:02 located within the major histocompatibility complex (MHC) region, which was reported to be the outstanding variant associated with EOP. However, genetic structure of EOP and LOP have not been fully elucidated. Objective: To investigated HLA genetic heterogeneity between EOP and LOP in China. Methods: We first calculated the MHC-based heritability of EOP and LOP respectively. Then, we conducted a large-scale, stratified analysis including 7,097 EOP, 1,337 LOP patients, and 9,906 healthy controls by using MHC target sequencing data from a previous study. Results: We observed that HLA alleles collectively explained a larger heritability of EOP (27.4%) than LOP (11.3%). Further association analysis identified three independent loci (HLA-C*01:02, p=6.70×10^-8; HLA-A amino acid position 9, p=3.27×10^-17; and HLA-A amino acid position 161, p=5.75×10^-10) that confer specific susceptibility to EOP. Our data also confirmed HLA-C*06:02 as an independent psoriasis-associated variant, contributing a higher degree of risk to EOP than LOP. Moreover, case-case analysis confirmed that HLA-C*06:02-positive psoriasis patients have earlier onset. Conclusion: Our analysis indicating that different genetic background underlie the EOP and LOP. We believe these findings will serve to predict psoriasis risk in the future and facilitate clinical decision. (Ann Dermatol 33(1) 61∼67, 2021)

Empirical likelihood for the class of single index hazard regression models

Jianbo Li,Minglong Guo,Changxin Du,Riquan Zhang,Heng Lian 한국통계학회 2015 Journal of the Korean Statistical Society Vol.44 No.4

Based on the B spline approximation technique and right censored data, we consider the empirical likelihood inference for the index parameters and its partial components in a class of single index hazard regression models. Under some regular conditions, we show that our proposed empirical likelihood ratio statistics follow the standard χ2 distribution. Some numerical studies are given to illustrate our proposed methodology.

Clinical Significance of miR-21-5p in Predicting Occurrence and Progression of Uremic Vascular Calcification in Patients with End-Stage Renal Disease

Rong Wu,Sen Zhou,Minglong Liu,Haiqian An,Zhe Wang,Tianxi Liu 연세대학교의과대학 2022 Yonsei medical journal Vol.63 No.3

Purpose: Vascular calcification (VC) is a common complication of end-stage renal disease (ESRD). This study aimed to examinechanges in the expression of miR-21-5p in ESRD patients with VC and to explore its clinical value in predicting the occurrenceand progression of uremic VC. Materials and Methods: 120 ESRD patients were divided into patients without VC group (n=38) and patients with VC group(n=82). All patients were followed up for 2 years to evaluate VC progression. qRT-PCR was used to detect serum miR-21-5p levels. Receiver operating characteristic curves were constructed to assess diagnostic value. Kaplan-Meier and log-rank methods wereutilized to calculate associations between VC progression and risk factors. Results: Serum miR-21-5p levels were significantly higher in ESRD patients with VC than in those without VC and increased progressivelywith increasing disease severity. Serum miR-21-5p levels were able to distinguish patients with VC from those withoutVC, with an area under the curve value of 0.883, a sensitivity of 81.7%, and a specificity of 84.2%. After 2 years of follow-up, miR-21-5p expression had increased in patients with worse VC severity, compared with those with stable VC severity. Patients withhigh miR-21-5p levels were more likely to develop more severe VC, indicating an association between miR-21-5p and VC progression(log-rank p=0.002). Multivariable Cox regression analysis suggested that serum miR-21-5p is an independent predictive factorof VC progression in ESRD patients (hazard ratio=2.064, 95% confidence interval=1.225–3.478, p=0.006). Conclusion: miR-21-5p is overexpressed in the serum of ESRD patients with VC. Our results suggest that overexpression of miR-21-5p is closely associated with VC progression.

IDENTIFYING AND TESTING ON-SITE STIMULI AT INDUSTRIAL HERITAGE TOURISM DESTINATIONS IN THE DIGITIZATION CONTEXT

Qiushi Gu,Wanting Liu,Minglong Li 글로벌지식마케팅경영학회 2023 Global Marketing Conference Vol.2023 No.07

Digital technology has been increasingly applied in the traditional tourism forms, including the heritage tourism. However, the role of technology and tradition for attracting tourists in industrial heritage tourism destinations has not been clearly identified. To narrow the research gaps, this study adopted a two stage study, based on grounded theory and factor analyses. In Study 1, through the data analysis of 60 in-depth interviews, 10 stimuli factors in 3 categories were identified. In Study 2, a questionnaire was developed based on the results of Study 1, through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), we established and tested a model of on-site stimulus factors. Findings can deepen the understanding of industrial heritage tourism from a tourist perspective and offer practical implications.

Nonlinear Aeroelastic Analysis of Heated Curved Panels in Supersonic Air Flow

Zhou Jian,Xu Minglong,Yang Zhichun 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.4

A nonlinear aeroelastic model for a two-dimensional heated curved panel in supersonic air flow is established by using Galerkin method. The von Karman large deflection theory and the third-order piston theory appended with the static aerodynamic loading are used in the governing equations. The static aero-thermal deflection of the curved panel is firstly obtained by using Newton iterative approach. Then the stability boundary under different temperature elevations is achieved by using Lyapunov’s indirect method. Lastly, the motion equations of a heated curved panel in supersonic air flow are solved by a fourth-order Runge–Kutta numerical scheme. Time history responses, phase plots, Poincare maps and bifurcation diagrams are used for better understanding of the pre/post-flutter responses of a curved panel by varying parameters, including curvatures, dynamic pressures and temperature elevations. The results demonstrate that the flutter boundary drops significantly with increasing temperature elevation for panels with small curvatures. However, the flutter boundary almost keeps the same for panels with large curvatures. The nonlinear flutter characteristics of the curved panel differs from those of flat panels significantly, the nonlinear flutter response of heated curved panels changes from static equilibrium point or LCO to chaos with the increase of temperature elevation or dynamic pressure and the static, LCO motions also exist in the chaotic area. For panels with large curvatures, the chaotic motions cannot occur, and the amplitude of LCO is limited in a certain range.

Anti-hyperuricemic and nephroprotective effects of Rhizoma Dioscoreae septemlobae extracts and its main component dioscin via regulation of mOAT1, mURAT1 and mOCT2 in hypertensive mice

Junxia Su,Yu-Hui Wei,Minglong Liu,Tianxi Liu,Jianhua Li,Yuanchun Ji,Jianping Liang 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.10

Rhizoma Dioscoreae septemlobae (RDSE) hasbeen widely used for the treatment of hyperuricemia inChina. However, the therapeutic mechanism has beenunknown. This study investigated the antihyperuricemicmechanisms of the extracts obtained from RDSE and itsmain component dioscin (DIS) in hyperuricemic mice. Hyperuricemic mice were induced by potassium oxonate(250 mg/kg). RDSE or DIS was orally administered tohyperuricemic mice at dosages of 319.22, 638.43,1276.86 mg/kg/day for 10 days, respectively. Uric acid orcreatinine in serum and urine was determined by HPLC orHPLC–MS/MS, respectively. The xanthine oxidase (XO)activities in mice liver were examined in vitro. Proteinlevels of organic anion transporter 1 (mOAT1), uratetransporter 1 (mURAT1) and organic cation transporter 2(mOCT2) in the kidney were analyzed by western blotting. The results indicated that uric acid and creatinine in serumwere significantly increased by potassium oxonate, ascompared to that of control mice. Compared saline-treatedgroup, after RDSE treatment in the high and middle dose,the expression of mOAT1 increased 47.98 and 54.48 %,respectively, which accompanied with the decreasedexpression of mURAT1 (47.63 %) in high dose. After DIS treatment in high, middle and low dose, the expression ofmOAT1 increased 23.93, 32.80 and 25.28 % compared tosaline-treated group, respectively, which accompanied withthe decreased expression of mURAT1 (51.07, 51.42 and51.35 %). However, RDSE and DIS displayed a weak XOinhibition activity compared with allopurinol. Therefore,RDSE and DIS processed uricosuric and nephroprotectiveactions by regulation of mOAT1, mURAT1 and mOCT2.

The role of microenvironment in aggregation of the 293-human embryonic Kidney cells

Wensong Tan,Liang Zhao,Li Fan,Xu Zhang,Minglong Zhu 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.5

cells. Key factors such as calcium, magnesium and shear stres were investigated in detail and cell aggregate size con-trol was applied to facilitate cell retention improvement. It was found that the concentration of calcium ion affectedthe aggregation of 293-HEK cells drastically and exhibited direct proportion to the average diameter of 293-HEK cellaggregates. Similar effect was also discovered in magnesium but to a lower extend. Results also showed the growthof 293-HEK cells was influenced when the concentrations of calcium or magnesium ions were below 0.1 mol/L,and that was more significant with magnesium. Furthermore, aggregation as well as growth was affected by hard in-trolled to proper size as anticipated and the average sedimentation speed of agregated cells increased about 20 timesto single cells. This is highly advantageous to cell retention improvement either in perfusion cultures or media exchangebefore adenovirus infection by proper control of the cell aggregate size, and thus a high cell concentration and ad-enovirus production potentially can be achieved.