Enhancement of Impurity, Machinability and Mechanical Properties in Te-Treated 0Cr18Ni9 Steel

Jian‑bo Xie,Tian Fan,Han Sun,Zhi‑qi Zeng,Jian‑xun Fu 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.6

To enhance the machinability and mechanical properties of 0Cr18Ni9 steel, free-machining element Te was introduced inthis work. By adding various quantities of Te to steel, several machining and tensile tests were carried out. Results show thatwith Te addition of 530 ppm, the number of inclusion sizes below 1 μm disappeared. With raising Te from 360 to 530 ppm,more MnTe–MnS inclusions of 10–40 μm were in spherical shape; above 50 μm2, the ratio of inclusion area at 530 ppmwas greatest among all, and the large-sized inclusions occupied a larger share. Te addition contributed to the surfaces ofmachining steels more smooth. The ultimate tensile strength of steel increased from 399 to 435 MPa. Te resulted in growthof sulfides and improved the machinability of steel.

Long Term Outcomes and Prognostic Factors of N₀ Stage Nasopharyngeal Carcinoma: a Single Institutional Experience with 610 Patients

Sun, Jian-Da,Chen, Chuang-Zhen,Chen, Jian-Zhou,Li, Dong-Sheng,Chen, Zhi-Jian,Zhou, Ming-Zhen,Li, De-Rui Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Treatment responses of $N_0$ stage nasopharyngeal carcinoma were firstly analyzed comprehensively to evaluate long term outcomes of patients and identify prognostic factors. A total of 610 patients with $N_0$ NPC, undergoing definitive radiotherapy to their primary lesion and prophylactic radiation to upper neck, were reviewed retrospectively. Concomitant chemotherapy was administrated to 65 out of the 610. Survival rates of the patients were calculated using the Kaplan-Meier method and compared by log-rank test. Prognostic factors were identified by the Cox regression model. The study revealed the 5-year and 10-year overall, disease-free, disease-specific, local failure-free, regional failure-free, locoregional failure-free and distant metastasis-free survival rates to be 78.7% and 66.8%, 68.8% and 55.8%, 79.9% and 70.4%, 81.2% and 72.5%, 95.8% and 91.8%, 78.3% and 68.5%, 88.5% and 85.5%, respectively. There were 192 patients experiencing failure (31.5%) after radiotherapy or chemoradiotherapy. Of these, local recurrence, regional relapse and distant metastases as the first event of failure occurred in 100 (100/610, 16.4%), 15(15/610, 2.5%) and 52 (52/610, 8.5%), respectively. Multivariate analysis showed that T stage was the only independent prognostic factor for patients with $N_0$ NPC (P=0.000). Late T stage (P=0.000), male (P=0.039) and anemia (P=0.007) were independently unfavorable factors predicting disease-free survival. After treatment, satisfactory outcome wasgenerally achieved in patients with $N_0$ NPC. Local recurrence represented the predominant mode of treatment failure, while T stage was the only independent prognostic factor for overall survival. Late T stage, male gender, and anemia independently predicted lower possibility of the disease-free survival.

Stress Distribution and Failure Characteristics for Workface Floor of a Tilted Coal Seam

Jian Sun,Lianguo Wang,Guangming Zhao 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.9

A mechanical model for the tilted workface floor along the tilted direction of coal seam was proposed. Stress expressions of an arbitrary point inside the tilted workface floor were deduced. Calculation formula for the maximum failure depth of the lateral floor strata of the tilted workface was also deduced. Based on the Mohr-Coulomb yield criterion, the tilted workfacefloor’s stress distribution, and failure depth and shape were simulated by using FLAC3D software for different coal seam’s dip angles, buried depths, and workface widths. Results show that the concentration coefficient, the peak value and the distance between the peak position of the lateral abutment pressure and the roadway on both sides of the tilted workface decreases with the increases in coal seam’s dip angle. The vertical stress isoclines present a “spoon-shaped” distribution along the tilteddirection of workface. Both sides of the workface form “bubble-shaped” distribution shear stress and its peak value increases first and then decreases with the increases in coal seam’s dip angle and reaches maximum at 30°–35°. The tilted workface floor’s plastic failure zone presents a “spoon-shaped” distribution along the tilted direction of workface, which is large on the lower side and small on the upper side. The plastic zone’s failure depth increases first and then decreases with the increases in the dip angle of coal seam and reaches maximum at 30°.

Novel 5-Fluorouracil Derivatives: Synthesis and Cytotoxic Activity of 2-Butoxy-4-Substituted 5-Fluoropyrimidines

Jian Sun,Shi-Jie Zhang,Hai-Bo Li,Wei Zhou,Wei-Xiao Hu,Shang Shan 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.5

Twenty two new 5-fluorouracil (5-FU) derivatives, 2-butoxy-4-substituted 5-fluoropyrimidines, were synthesized and characterized by IR, 1H NMR, MS, HRMS. All compounds were preliminarily evaluated by MTT assay on human liver BEL-7402 cancer cell line in vitro. Ten compounds were selected to test their cytotoxic activity against A549, HL-60 and MCF-7 cancer cell lines in vitro. These compounds were more sensitive to BEL-7402 than other cell lines, particularly, cytotoxic activity of compounds 6b, 6d-f, 6p, 6s-u were in sub-micromolar scale. The highest cytotoxic potency against A549, HL-60 and MCF-7 was shown by 2-butoxy-4-chloro-5- fluoropyrimidine (5) with IC50 values of 0.10, 1.66 and 0.59 μM, respectively. Compounds 6d and 6e were effective against MCF-7 with IC50 9.73 μM and HL-60 with IC50 8.83 μM, respectively.

POSITIVE SOLUTION FOR FOURTH-ORDER FOUR-POINT STURM-LIOUVILLE BOUNDARY VALUE PROBLEM

Jian-Ping Sun,Xiao-Yun Wang 한국전산응용수학회 2010 Journal of applied mathematics & informatics Vol.28 No.3

This paper is concerned with the following fourth-order four-point Sturm-Liouville boundary value problem [수식]Some sufficient conditions are obtained for the existence of at least one positive solution to the above boundary value problem by using the well-known Guo-Krasnoselskii fixed point theorem.

The Long Non-Coding RNA CASC2 Suppresses Cell Viability, Migration, and Invasion in Hepatocellular Carcinoma Cells by Directly Downregulating miR-183

Jian Sun,Lijun Liu,Huilian Zou,Wei Yu 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.10

Purpose: Hepatocellular carcinoma (HCC) is the most common malignant tumor of liver cells. Researchers have reported thatcancer susceptibility candidate 2 (CASC2), a long non-coding RNA, is down-regulated in various cancers, including HCC. Ourstudy aimed to investigate the molecular mechanism(s) of CASC2 in HCC. Materials and Methods: Real-time quantitative PCR (RT-qPCR) was used to analyze the expression of CASC2 and miR-183 inHCC tissues and cells. The viability of HCC SMMC-7721 and Huh-7 cells was detected through MTT assay. Colony formation assaywas performed to assess the colony formation ability of HCC cells. The migration and invasion abilities of HCC cells were evaluatedby Transwell assay. Western blot was conducted to examine levels of key Wnt/β-catenin signaling pathway factors, C-myc, cyclinD,survivin, and β-catenin. The interaction between CASC2 and miR-183 was affirmed by bioinformatics analysis andluciferase reporter assay. Results: CASC2 was down-regulated in HCC tissues and cell lines, while miR-183 was up-regulated. The expression of miR-183was negatively correlated with CASC2 expression in HCC tissues. Overexpression of CASC2 inhibited cell viability, colony formation,migration, and invasion in HCC cells, as well as Wnt/β-catenin signaling pathway activity. miR-183 was a downstream targetof CASC2 and negatively regulated by CASC2. Introduction of miR-183 rescued CASC2-induced suppressive effects on HCC cellviability, colony formation, migration, and invasion and Wnt/β-catenin signaling. Conclusion: CASC2 inhibited cell viability and the colony formation, migration, and invasion abilities of HCC cells by directlydownregulating miR-183 through inactivation of the Wnt/β-catenin signaling pathway.

Study on the Influence of Population Aging on the Economic Development of Shandong Province

Jian quan Sun 한국유통과학회 2017 한국유통과학회 학술대회 논문집 Vol.2017 No.-

The change of population structure will inevitably have an impact on social and economic development, especially on the existing old-age security system and the labor market. This paper analyzed the economic development situation in Shandong province and the aging of the population, discussed the mechanism of the impact of population aging on economic development. By means of econometric analysis, this paper studied the mutual influence between population aging and economic growth in Shandong Province, and draw a conclusion that the aging population has a certain degree of slowing down effect on regional economic development. The aging of the population has a profound impact on the development of regional economy and its impact on regional economic development in the long run will be more obvious. In essence, population aging is not the ultimate decisive factor in economic development, but its regional economic development has a certain deceleration effect.

A New Political Era, A New Korean Peninsula

Sun, Jian Hang(토론자) 한반도선진화재단 2013 한반도선진화재단 기타 단행본 Vol.- No.-

Pseudorapidity Distributions of Charged Particles Produced in pp Collisions at the CERN LHC Energies

Jian-Xin Sun,Cai-Xing Tian,Er-Qin Wang,Fu-Hu Liu 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.5

The pseudorapidity distributions of charged particles produced in pp collisions at the CERN Large Hadron Collider (LHC) energies (0.9, 2.36, and 7 TeV) are studied by using the multisource thermal model. A group of extrapolated equations is used to determine various parameters. The calculated results are in agreement with the experimental data of the ALICE and CMS Collaborations at the LHC.

Association Between XRCC1 Gene Polymorphisms and Risk of Glioma Development: A Meta-analysis

Sun, Jian-Ying,Zhang, Chun-Yang,Zhang, Zhen-Jun,Dong, Yan-Fang,Zhang, An-Long,Wang, Zhi-Wei,Mei, Xiao-Long Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Objective: Previous studies of the association between X-ray cross-complementing group 1 (XRCC1) gene polymorphisms and the gliomas risk have yielded conflicting results, and thus a meta-analysis was performed to provide a more accurate estimation. Methods: A computerized literature search of 5 electronic databases was conducted to identify the relevant studies. Fixed or random effect models were selected based on the heterogeneity test. Publication bias was estimated using Begg's funnel plots and Egger's regression test. Results: A total of 11 studies (3,810 cases and 6,079 controls), 7 studies (2,928 cases and 5,048 controls), and 4 studies (1,461 cases and 2,593 controls) were finally included in the analyses of the association between XRCC1 Arg399Gln, Arg194Trp, and Arg280His polymorphisms and glioma risk, respectively. The pooled results showed that GlnGln carriage was associated with moderately increased risk of gliomas in Asians (GlnGln vs. ArgArg, OR=1.490, 95%CI 1.031-2.153; GlnGln/ArgGln vs. ArgArg, OR=1.321, 95%CI 1.037-1.684), whereas a marginal association was revealed in Caucasians. For the Arg194Trp polymorphism, although a significant association was shown in the homozygous genotype comparisons (TrpTrp vs. ArgArg, OR = 2.209, 95%CI 1.398-2.945), no significant link was found on subgroup analysis stratified by ethnicity. With regard to the Arg280His polymorphism, no significant association was found in each comparison. No particular study was found to significantly influence the pooled results, and no potential publication bias was detected. Conclusions: This meta-analysis suggested that the XRCC1 Arg399Gln polymorphism is moderately associated with increased risk of gliomas in Asians, while Arg194Trp and Arg280His polymorphisms demonstrated no significant influence. Due to the limited studies and the potential confounders, further studies are needed to confirm these results.