Analysis of genetic diversity among indigenous landraces from sesame (Sesamum indicum L.) core collection in China as revealed by SRAP and SSR markers

Yan‐xin Zhang,Wei Hua,Lin‐han Wang,Zhuo Che,Xiu‐rong Zhang 한국유전학회 2010 Genes & Genomics Vol.32 No.3

The molecular genetic diversity of 404 indigenous landraces from sesame core collection in China were evaluated by 11SRAP and 3 SSR markers, 175 fragments were generated, of which 126 were polymorphic with an average polymorphism rate of 72%. Jaccard’s genetic similarity coefficients (GS=0.7130), Nei's gene diversity (h=0.2418) and Shannon's Information index (I=0.3847) were calculated, a dendrogram of the 404 landraces was made, landraces from various zones were distributed throughout the dendrogram, accessions from different agro‐ecological zones were indistinguishable by cluster analysis, geographical separation did not generally result in greater genetic distance, a similar pattern was obtained using principal coordinates (PCO) analysis. As to seven agro‐ecological zones, the maximum Nei’s gene diversity (h = 0.2613)and Shannon index (I = 0.3980) values in zone VII indicated that they were genetically more diverse than those in other zones, while the least genetically diverse region was zone III (h = 0.1772, I = 0.2858). Nei's genetic identity and genetic distance among landraces from seven agro‐ecological zones were also analyzed, the genetic relationship of seven zones was inferred using the UPGMA method. This study demonstrated that SRAP and SSR markers were appropriate for evaluation of sesame genetic diversities. There existed extensive genetic diverse among indigenous landraces and the abundance of genetic diversity of landraces in different agro‐ecological zones was various. Understanding of these characteristics of indigenous landraces in China can provide theoretical foundation for further collection, effective protection and reasonable utilization of these sesame landraces in breeding.

Numerical investigations into the rubbing wear behavior of honeycomb seal

Xin Yan,Haibo Wang,Kun He 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.8

The rubbing wear behavior of the honeycomb land against labyrinth fin was investigated with finite-element-analysis method at a range of incursion conditions. The contact behaviors, material property, and material damage and failure are computed within the userdefined-subroutines. With the experimental data, the finite-element-analysis method was validated with respect to the frictional temperature and worn geometry. The effects of stator material, incursion depth, incursion rate and sliding velocity on the contact force, frictional temperature, material loss, and worn geometry are analyzed. The results show that the sliding velocity, final incursion depth and incursion rate are the important factors affecting the wear behaviors of honeycomb stator. The mushrooming extension is decreased with the increase of sliding velocity, and increased with the increase of incursion rate. At high sliding velocity and low incursion rate conditions, the material loss accounts more in the wear volume deformation compared to the plastic deformation.

Ascorbic Acid Alleviates Pancreatic Damage Induced by Dibutyltin Dichloride (DBTC) in Rats

Xin-Liang Lu,Yan-Hua Song,Yan-Biao Fu,Jian-Min Si,Ke-Da Qian 연세대학교의과대학 2007 Yonsei medical journal Vol.48 No.6

Purpose: Because previous studies have reported depleted antioxidant capacity in patients with chronic pancreatitis (CP), prevention of free radical production has gained importance in antifibrotic treatment strategies for CP. The aim of this study was to investigate the effects of ascorbic acid on oxidative capacity and pancreatic damage in experimental CP. Materials and Methods: CP was induced in male Sprague-Dawley rats by infusion of dibutyltin dichloride (DBTC) into the tail vein. Ascorbic acid was given intraperitoneally at a daily dose of 10mg/kg body weight. The treatment groups were as follows: group 1, DBTC plus intraperitoneal physiologic saline; group 2, DBTC plus intraperitoneal ascorbic acid; group 3, solvent plus intraperitoneal physiologic saline; group 4, no operation plus intraperitoneal physiologic saline. Each group contained 15 animals. Treatment was started after CP was established. After 4 weeks of treatment, serum hyaluronic acid and laminin levels were determined by radioimmunoassay, pancreatic tissue oxidative stress was analyzed, and the degree of pancreatic damage was determined. Results: Ascorbic acid treatment markedly increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) concentrations in pancreatic tissue (p<0.01 for both). Significant serum hyaluronic acid and laminin reductions were observed in group 2 as compared with group 1 (p<0.05). However, the serum hyaluronic acid and laminin levels remained elevated when compared with those of groups 3 and 4 (p<0.05). Histopathologic scores were also lower in animals with CP that underwent ascorbic acid-treatment (p<0.05). Conclusion: Ascorbic acid treatment alleviated the degree of oxidative stress and pancreatic damage in rat CP. Antioxidant treatment might be considered a potential option to improve the pathologic process in CP.

Amentoflavone protects the hematopoietic system of mice against γ‑irradiation

Xin-yan Qu,Qingjun Li,Xiao-juan Zhang,Zhaofen Wang,Shengqi Wang,Zhe Zhou 대한약학회 2019 Archives of Pharmacal Research Vol.42 No.11

Some flavonoids have been shown to exhibitgood antioxidant activity and protect mice from damageinduced by radiation. Amentoflavone (AMF), a biflavonoidderived from the traditional herb-Selaginella tamariscina,has been reported to have antioxidant properties. The protectiveeffects and mechanism of action of AMF against radiationinjury remain unknown. In this study, male C57BL/6mice were subjected to total-body 60Co γ-irradiation at 7.5or 3.0 Gy. The survival rate and mean survival time wereevaluated to determine the radioprotective effect of AMF. Number of peripheral blood cells, frequency of colony formingunit-granulocytes, monocytes and micronuclei weremeasured to assess the protective effects of AMF on thehematopoietic system. Levels of superoxide dismutase andglutathione, and pathological changes in the bone marrowwere determined. Additionally, next-generation sequencingtechnology was used to explore potential targets of AMF. Weobserved that AMF markedly extends average survival time,reduces injury to the hematopoietic system and promotes itsrecovery. Furthermore, treatment with AMF significantlyattenuated radiation-induced oxidative stress. In addition,AMF had a significant effect on gene tumor necrosis factor alpha-induced protein 2. Together, the results of this studysuggest that AMF is a potential protective agent againstradiation injury.

Suzhou impression

Yan Xin Wen 한국콘텐츠학회 2019 ICCC International Digital Design Invitation Exhib Vol.2019 No.12

Primary School Students` Understanding of Equation Structure and the Meaning of Equal Sign: A Chinese Sample Study

( Xin Rong Yang ),( Yu Jia Huo ),( Yan Xiong Yan ) 한국수학교육학회 2014 수학교육연구 Vol.18 No.4

This paper reports findings from a written assessment which was designed to investigate Chinese primary school students`` understanding of the equal sign and equation structure. The investigation included a sample of 110 Grade 3, 112 Grade 4, and 110 Grade 5 students from four schools in China. Significant differences were identified among the three grades and no gender differences were found. The majority of Grades 3 and 4 students were found to view the equal sign as a place indicator meaning "write the answer here" or "do something like computation", that is, holding an operational view of the equal sign. A part of Grade 5 students were found to be able to interpret the equal sign as meaning "the same as", that is, holding a relational view of the equal sign. In addition, even though it was difficult for Grade 3 students to recognize the underlying structure in arithmetic equation, quite a number of Grades 4 and 5 students were able to recognize the underlying structure on some tasks. Findings in this study suggest that Chinese primary school students demonstrate a relational understanding of the equal sign and a strong structural sense of equations in an earlier grade. Moreover, what found in the study support the argument that students`` understanding of the equal sign is influenced by the context in which the equal sign is presented.

Review : Purification and Characterization of a Novel Extracellular Thermostable Alkaline Protease from Streptomyces sp. M30

( Yan Xin ),( Zhibin Sun ),( Qiongzhen Chen ),( Jue Wang ),( Yicheng Wang ),( Linfeng Luogong ),( Shuhuan Li ),( Weiliang Dong ),( Zhongli Cui ),( Yan Huang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.11

A novel alkaline protease from Streptomyces sp. M30, SapHM, was purified by ammonium sulfate precipitation, hydrophobic interaction chromatography, and DEAE-Sepharose chromatography, with a yield of 15.5% and a specific activity of 29,070 U/mg. Tryptic fragments of the purified SapHM were obtained by electrospray ionization quadrupole timeof- flight mass spectrometry. Nucleotide sequence analysis revealed that the gene sapHM contained 1,179 bp, corresponding to 392 amino acids with conserved Asp156, His187, and Ser339 residues of alkaline protease. The first 24 amino acid residues were predicted to be a signal peptide, and the molecular mass of the mature peptide was 37.1 kDa based on amino acid sequences and mass spectrometry. Pure SapHM was optimally active at 80°C in 50 mM glycine-NaOH buffer (pH 9.0), and was broadly stable at 0-50°C and pH 4.0-9.0. The protease relative activity was increased in the presence of Ni2+, Mn2+, and Cu2+ to 112%, 113%, and 147% of control, respectively. Pure SapHM was also activated by dimethylformamide, dimethyl sulfoxide, Tween 80, and urea. The activity of the purified enzyme was completely inhibited by phenylmethylsulfonyl fluoride, indicating that it is a serine-type protease. The Km and Vmax values were estimated to be 35.7 mg/ml, and 5 × 104 U/mg for casein. Substrate specificity analysis showed that SapH was active on casein, bovine serum albumin, and bovine serum fibrin.

Investigations into film cooling and unsteady flow characteristics in a blade trailing-edge cutback region

Yan Gao,Xin Yan,Jun Li,Kun He 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

Unsteady flow characteristic and film cooling effect in the blade trailing edge cutback region are numerically investigated using DES (detached eddy simulation) method at three blowing ratios, four lip thickness ratios and three rib geometries. With the experimental data, reliability and accuracy of the numerical methods are validated. The results indicate that, compared with RANS (Reynolds-averaged Navier-Stokes) equations solutions, the DES method has a superior accuracy in predicting the film cooling effectiveness on trailing-edge cutback. The lip thickness has a pronounced effect on shedding vortex scale downstream the slot. As the lip thickness ratio decreases, the film cooling effect on trailing edge cutback is improved. Compared with the line ribs, the arrangement of pin fin ribs enhances the uniformity of coolant coverage on trailing edge cutback along lateral direction. However, with different types of rib, the film cooling effectiveness on the trailing edge cutback is mainly determined by the stable cooling flow structures and mixing effect between mainstream and coolant. The development of vortex system downstream the slot is significantly affected by the blowing ratio, which in turn influences the film cooling effect on trailing edge cutback.

Effect of teeth bending and mushrooming damages on leakage performance of a labyrinth seal

Xin Yan,Xinbo Dai,Kang Zhang,Jun Li,Kun He 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

To achieve higher aerodynamic performance, turbine usually works at tight clearance, which results in inevitable rub between the rotor and stator parts of labyrinth seal due to vibrations, misalignment, mechanical force, thermal stress, etc. In the rubbing events, contact between labyrinth fin and rotor part will commonly induce the teeth bending and mushrooming damages, which significantly affect the discharge performance of a labyrinth seal. To account for the influence of teeth bending and mushrooming on leakage performance of a straight-through labyrinth seal, the leakage rates and flow fields in the worn labyrinth seal are measured and also compared with the original design cases. With numerical methods, the discharge behaviors of the labyrinth seal with different degrees of bending and mushroom damages are analyzed. It shows that the predicted leakage performance and flow fields in the labyrinth seals match well with the experimental tests. For the bending cases, the leakage rates and flow patterns in labyrinth seals are dependent on the effective clearance and bending angle. The leakage ratio of forward bending case is smaller than that of backward bending case with the same geometrical dimensions. However, for the mushroomed labyrinth seals, the leakage rates and flow patterns are much dependent on the effective clearance but slightly dependent on the mushroom radius.

LPL gene Pvu II polymorphism and hypertriglycer-idemia: a meta-analysis involving 1,640 subjects

( Yan-yan Li ),( Yan-hong Zhou ),( Ge Gong ),( Hong-yu Geng ),( Xin-xing Yang ),( Xiang-ming Wang ),( Chuan-wei Zhou ),( Jian Xu ),( Yun Qian ) 대한내과학회 2017 The Korean Journal of Internal Medicine Vol.32 No.6

Background/Aims: Although lipoprotein lipase (LPL) gene Pvu II polymorphism has been associated with an increased risk of hypertriglyceridemia (HT), there is no clear consensus within the scientific community. Methods: A meta-analysis of 1,640 subjects from six individual studies was conducted to better elucidate the potential relationship between the LPL gene Pvu II polymorphism and HT within the Chinese population. Pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were evaluated by using fixed effect models. Results: Our analysis indicated a significant association between LPL gene Pvu II polymorphism and HT within the Chinese population under allelic (OR, 1.550; 95% CI, 1.320 to 1.830; p = 1.158 × 10^-7), recessive (OR, 0.540; 95% CI, 0.390 to 0.750; p = 0.0002), dominant (OR, 1.889; 95% CI, 1.501 to 2.377; p = 5.960 × 10^-8), homozygous (OR, 2.167; 95% CI, 1.531 to 3.067; p = 1.242 × 10^-5), heterozygous (OR, 1.810; 95% CI, 1.419 to 2.309; p = 1.842 × 10^-6), and additive genetic models (OR, 1.553; 95% CI, 1.320 to 1.828; p = 1.158 × 10^-7). Conclusions: Because LPL gene Pvu II restriction fragment length polymorphism polymorphism was associated with an elevated risk of HT, the P+ allele carriers of the LPL gene might be predisposed to HT.