Step-size adaptive parametric level set method for structural topology optimization

Chen-Dong Yang,Jian-Hu Feng,Ya-Dong Shen 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.10

In the structural topology optimization (STO), the step-size of the parametric level set method (PLSM) using the explicit scheme must satisfy the Courant-Friedrichs-Lewy (CFL) condition to ensure numerical stability. However, much larger step-sizes are arbitrarily used to speed up the convergence. For this reason, a narrowband in the velocity field is defined, and the step-size adaptive parametric level set method (SAPLSM) is proposed, which multiplies different step-sizes for the velocity of different nodes. The SAPLSM satisfies the CFL condition not only on the narrowband, but also on the entire design domain. Furthermore, a narrowband annealing (NA) scheme based on “annealing” is proposed to dynamically adjust the maximum step-size during the iterations. Numerical experimental results of several benchmark problems in two-dimensional minimum compliance show that: (1) The SAPLSM is more stable than PLSM under large step-sizes and complex problems. (2) The NA scheme not only accelerates the convergence of SAPLSM but also alleviates mesh dependence.

Comparison of Microbial Diversity and Composition in the Jejunum and Colon of Alcohol-Dependent Rats

( Yang Fan ),( Zhao Ya-e ),( Wei Ji-dong ),( Lu Yu-fan ),( Zhang Ying ),( Sun Ya-lun ),( Ma Meng-yu ),( Zhang Rui-ling ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.11

Alcohol dependence is a global public health problem, yet the mechanisms of alcohol dependence are incompletely understood. The traditional view has been that ethanol alters various neurotransmitters and their receptors in the brain and causes the addiction. However, an increasing amount of experimental evidence suggests that gut microbiota also influence brain functions via gut-to-brain interactions, and may therefore induce the development of alcohol use disorders. In this study, a rat model of alcohol dependence and withdrawal was employed, the gut microbiota composition was analyzed by high-throughput 16S rRNA gene sequencing, and the metagenome function was predicted by PICRUSt software. The results suggested that chronic alcohol consumption did not significantly alter the diversity and richness of gut microbiota in the jejunum and colon, but rather markedly changed the microbiota composition structure in the colon. The phyla Bacteroidetes and eight genera including Bacteroidales S24-7, Ruminococcaceae, Parabacteroides, Butyricimonas, et al were drastically increased, however the genus Lactobacillus and gauvreauii in the colon were significantly decreased in the alcohol dependence group compared with the withdrawal and control groups. The microbial functional prediction analysis revealed that the proportions of amino acid metabolism, polyketide sugar unit biosynthesis and peroxisome were significantly increased in the AD group. This study demonstrated that chronic alcohol consumption has a dramatic effect on the microbiota composition structure in the colon but few effects on the jejunum. Inducement of colonic microbiota dysbiosis due to alcohol abuse seems to be a factor of alcohol dependence, which suggests that modulating colonic microbiota composition might be a potentially new target for treating alcohol addiction.

Updated Assessment of the Association of the XRCC1 Arg399Gln Polymorphism with Lung Cancer Risk in the Chinese Population

Yang, Hai-Yan,Yang, Si-Yu,Shao, Fu-Ye,Wang, Hai-Yu,Wang, Ya-Dong Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Background: Published studies have reported relationships between X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism and lung cancer risk in Chinese population. However, the epidemiological results remained controversial. The objective of this study was to clarify the association of XRCC1 Arg399Gln polymorphism with lung cancer risk in the Chinese population. Materials and Methods: Systematic searches were performed through the database of Medline/Pubmed, Web of Science, Embase, CNKI and WanFang Medical Online. Odds ratios (ORs) with 95% confidence interval (95%CI) were calculated to estimate the strength of the association. Results: Overall, we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Gln/Gln genotype (OR=1.36, 95%CI: 1.09-1.71) in the Chinese population on the basis of 19 studies with 5,416 cases and 5,782 controls. We did not observe any association between XRCC1 codon 399 Arg/Gln and Arg/Gln+Gln/Gln polymorphisms and lung cancer risk (OR=1.00, 95%CI: 0.92-1.08 and OR=1.05, 95%CI: 0.97-1.13, respectively). Limiting the analysis to studies with controls in agreement with Hardy-Weinberg equilibrium (HWE), we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Gln/Gln genotype (OR=1.18, 95%CI: 1.01-1.38). When stratified by source of control, we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Arg/Gln+Gln/Gln genotype on the basis of hospitalized patient-based controls (OR=1.21, 95%CI: 1.04-1.42) and among subjects carrying XRCC1 codon 399 Gln/Gln genotype on the basis of healthy subject-based controls (OR=1.22, 95%CI: 1.04-1.43). Conclusions: Our findings indicated that certain XRCC1 Arg399Gln variants might affect the susceptibility of lung cancer in Chinese population. Larger sample size studies are required to confirm our findings.

A New High-Yielding Mungbean Cultivar, "Samgang" with Lobed Leaflet

Ya Seong Lee,Jeong Yang Lee,Dong Kwan Kim,Chang Yong Yoon,Guy Cheol Bak,In Jin Park,Geuk Pil Bang,Jung Kyung Moon,Young Jin Oh,Kyung Soo Min 한국육종학회 2004 한국육종학회지 Vol.36 No.3

A new mungbean variety Samgang (Vigna radiata (L.) Wilczek) was improved from the cross between Keumseongnogdu and V2939 at the Jeollanam-do Agricultural Research & Extension Services (JARES) in 2002. Samgang has erect growth habit, lobed leaflet, green h

Antimicrobial Activities of Bacillus sp. BCNU 5003 Isolated from Tae-Baek Mountain

Ya Ell KIM,Uk Hee YANG,Hye Jung CHOI,Cheol Soo AHN,Young Kee JUNG,Dong Wan KIM,Woo Hong JOO 한국생물공학회 2010 한국생물공학회 학술대회 Vol.2010 No.4

Naphthalene Degradation by Bacillus sp. BCNU 5001 and BCNU 5008 Isolated from Industrial Effluents

Ya Ell KIM,Uk Hee YANG,Hye Jung CHOI,Yeon Hee CHOI,Cheol Soo AHN,Young Kee JEONG,Dong Wan KIM,Woo Hong JOO 한국생물공학회 2009 한국생물공학회 학술대회 Vol.2009 No.10

AKT1 Inhibitory DNAzymes Inhibit Cell Proliferation and Migration of Thyroid Cancer Cells

Yang, Le,He, Jin-Ting,Guan, Hong,Sun, Ya-Dong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

AKT1 is a member of the serine/threoine AGC protein kinase family involved in thyroid cancer metabolism, growth, proliferation and survival. It is overexpressed in thyroid tumors. In this study, we designed two AKT1 specific DNAzymes (DRz1 and DRz2) that target AKT1 mRNA. The results showed that DRz1 could decrease the expression of AKT1 by 58%. Furthermore, DRz1 significantly inhibited cell proliferation, induced apoptosis and inhibited invasion in SW597 cells. In addition, down-regulation of survivin expression was associated with decreased caspase-3, VEGF and MMP2 in SW597 cells after 24 h. In our study, the efficacy of DRz1 in decreasing AKT1 protein levels were better than DRz2. AKT1-DRz1 might have anti-tumorigenic activity and may provide the basis for a novel therapeutic intervention in thyroid cancer treatment.

The Characteristics and Survival Outcomes in Patients Aged 70 Years and Older with Nasopharyngeal Carcinoma in the Intensity-Modulated Radiotherapy Era

Ya-Nan Jin,Wang-Jian Zhang,Xiu-Yu Cai,Mei-Su Li,Wayne R. Lawrence,Si-Yang Wang,Dong-Mei Mai,Yu-Yun Du,Dong-Hua Luo,Hao-Yuan Mo 대한암학회 2019 Cancer Research and Treatment Vol.51 No.1

Purpose We aim to examine nasopharyngeal carcinoma (NPC) characteristics and survival outcomes in patients aged 70 years and older in the intensity-modulated radiotherapy (IMRT) era. Materials and Methods From 2006 to 2013, 126 non-metastatic NPC patients aged  70 years who were treated with IMRT +/ chemotherapy were included. Adult Comorbidity Evaluation 27 (ACE-27) was used to measure patient comorbidities. The overall survival (OS) and cancer-specific survival (CSS) were calculated with the Kaplan-Meier method, and differences were compared using the log-rank test. The Cox proportional hazards model was used to carry out multivariate analyses. Results For the entire group, only two patients (1.6%) presented stage I disease, and up to 84.1% patients had stage III-IVB disease. All patients had a comorbidity score of 0 in 24 (19.0%), 1 in 45 (35.7%), 2 in 42 (33.3%), and 3 in 15 (11.9%) patients. The main acute grade during radiotherapy was 3-4 adverse events consisting of mucositis (25.4%), bone marrow suppression (16.7%), and dermatitis (8.7%). After treatment, four patients (3.2%) developed temporal lobe injury. Five-year CSS and OS rates were 67.3% (95% confidence interval [CI], 58.6% to 77.4%) and 54.0% (95% CI, 45.6% to 63.9%), respectively. Five-year OS was significantly higher for ACE-27 score 0-1 than ACE-27 score 2-3 (72.9% and 39.9%, respectively; p < 0.001). Multivariate analyses showed ACE-27 score 0-1 was significantly associated with superior OS (hazard ratio [HR], 3.02; 95% CI, 1.64 to 5.55; p < 0.001). In addition, the rate of OS was higher for stage I-III than that of stage IV, with borderline significance (HR, 1.67; 95% CI, 0.99 to 2.82; p=0.053). But no significant advantage was observed in OS when chemotherapy was used (p > 0.05). Conclusion Our findings suggest IMRT +/– chemotherapy has a manageable toxicity and provides an acceptable survival in patients aged  70 years with NPC. ACE-27 score was significantly associated with survival outcomes in this group population.

Kinetics of Enzymatic Synthesis of L-ascorbyl Acetate by Lipozyme TLIM and Novozym 435

Dong-Hao Zhang,Ya-Qiong Li,Chao Li,Yv-Qin Lv,Yang-L 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.1

L-ascorbyl acetate was synthesized through lipase-catalyzed esterification using Lipozyme TLIM and Novozym 435. Four solvents, including methanol, ethanol,acetonitrile, and acetone were investigated for the reaction,and acetone and acetonitrile were found to be suitable reaction media. The influences of several parameters such as water activity (aw), substrate molar ratio, enzyme loading,and reaction temperature on esterification of Lascorbic acid were systematically and quantitatively analyzed. Through optimizing the reaction, lipase-catalyzed esterification of L-ascorbic acid gave a maximum conversion of 99%. The results from using Lipozyme TLIM and Novozym 435 as biocatalysts both showed that aw was an important factor for the conversion of L-ascorbic acid. The effect of pH value on lipase-catalyzed L-ascorbic acid esterification in acetone was also investigated. Furthermore,results from a kinetic characterization of Lipozyme TLIM were compared with those for Novozym 435, and suggested that the maximum reaction rate for Lipozyme TLIM was greater than that for Novozym 435, while the enzyme affinity for substrate was greater for Novozym 436.

Increased Frequency of Micronuclei in Binucleated Lymphocytes among Occupationally Pesticide-exposed Populations: A Meta-analysis

Yang, Hai-Yan,Feng, Ruo,Liu, Jing,Wang, Hai-Yu,Wang, Ya-Dong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Background: The cytokinesis-block micronucleus (CBMN) assay is a standard cytogenetic tool employed to evaluate chromosomal damage subsequent to pesticide exposure. Objectives: To evaluate the pooled levels of total micronuclei (MN) and binucleated cells with micronuclei (MNC) in 1000 binucleated lymphocytes among population occupationally exposed to pesticides and further determine the more sensitive biomarker of CBMN. Materials and Methods: A meta-analysis on the pooled levels of MN and MNC in binucleated lymphocytes among occupationally pesticide-exposed populations was conducted using STATA 10.0 software and Review Manager 5.0.24 in this study. Results: We found significant differences in frequencies of MN and MNC in 1000 binucleated lymphocytes between pesticide-exposed groups and controls, and the summary estimates of weighted mean difference were 6.82 [95% confidence interval (95% CI): 4.86-8.78] and 5.08 (95% CI: 2.93-7.23), respectively. However, when we conducted sensitivity analyses further, only the MN remained statistically different, but not the MNC, the summary estimates of weight mean difference were 2.86 (95% CI: 2.51-3.21) and 0.50 (95% CI: -0.16-1.17), respectively. We also observed pesticide-exposed subjects had significantly higher MN frequencies than controls among smokers and nonsmokers, male and female populations, and American, Asian and European countries in stratified analyses. Conclusions: The frequency of MN in peripheral blood lymphocytes might be a more sensitive indicator of early genetic effects than MNC using the CBMN assay for occupationally pesticide-exposed populations.