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Genome Size Evolution Mediated by Gypsy Retrotransposons in Brassicaceae

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Genomics, Proteomics & Bioinformatics 2020年第3期18卷 321-332页

作者： shi-jian zhang Lei Liu Ruolin Yang Xiangfeng Wang Department of Crop Genomics and Bioinformatics College of Agronomy and BiotechnologyNational Maize Improvement Center of ChinaChina Agricultural UniversityBeijing 100094China Beijing Key Laboratory of Plant Resources Research and Development School of SciencesBeijing Technology and Business UniversityBeijing 100048China College of Life Sciences Northwest A&F UniversityYangling 712100China

The dynamic activity of transposable elements(TEs)contributes to the vast diversity of genome size and architecture among ***,we examined the genomic distribution and transposition activity of long terminal repeat retrotransposons(LTR-RTs)in Arabidopsis thaliana(Ath)and three of its relatives,Arabidopsis lyrata(Aly),Eutrema salsugineum(Esa),and Schrenkiella parvula(Spa),in *** analyses revealed the distinct evolutionary dynamics of Gypsy retrotransposons,which reflects the different patterns of genome size changes of the four species over the past million *** rate of Gypsy transposition in Aly is approximately five times more rapid than that of Ath and Esa,suggesting an expanding Aly *** insertions in Esa are strictly confined to pericentromeric heterochromatin and associated with dramatic centromere *** contrast,Gypsy insertions in Spa have been largely suppressed over the last million years,likely as a result of a combination of an inherent molecular mechanism of preferential DNA removal and purifying selection at Gypsy ***,species-specific clades of Gypsy elements shaped the distinct genome architectures of Aly and Esa.

关键词： Genome Size Evolution Mediated by Gypsy Retrotransposons in Brassicaceae

Experimental study on propagation characteristics of rotating detonation wave with kerosene fuel-rich gas

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Defence Technology（防务技术） 2022年第8期18卷 1498-1512页

作者： Jia-xiang Han Qiao-dong Bai shi-jian zhang Fang Wang Chun-sheng Weng National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing210094China

In this study, kerosene fuel-rich gas produced by the combustion in the gas generator was used as the fuel and oxygen-rich air was used as the oxidant to investigate the propagation characteristics of the rotating detonation wave (RDW). The initiation of the kerosene fuel-rich gas and propagation process of the RDW were analyzed. The influences of the oxygen content in the oxidizer, kerosene mass flow rate of the gas generator, and temperature of the kerosene fuel-rich gas on the propagation process of the RDW were studied. The experimental results revealed that the propagation velocity of the RDW could be improved by increasing the three parameters mentioned above with the kerosene mass flow rate as the strongest factor. The minimum oxygen content that could successfully initiate and maintain the stable propagation of the RDW was 32%, achieving the RDW velocity of 1141.9 m/s. The RDW mainly propagated as two-counter rotating waves and a single wave when the equivalent ratios were 0.62–0.79 and 0.85–0.87, respectively. The highest RDW velocity of 1637.2 m/s was obtained when the kerosene mass flow rate, oxygen content, and equivalent ratio were 74.6 g/s, 44%, and 0.87, respectively.

关键词： Rotating detonation wave Kerosene fuel-rich gas Initiation process Propagation mode

Relationship of distraction rate with inferior alveolar nerve degeneration-regeneration shift

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Neural Regeneration Research 2018年第2期13卷 360-365页

作者： Ying-hua Zhao shi-jian zhang Zi-hui Yang Xiao-chang Liu De-lin Lei Jing Li Lei Wang Department of Stomatology Huadong HospitalFudan UniversityShanghaiChina Department of Oral&Maxillofacial-Head&Neck Oncology Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Key Laboratory of Stomatology&Shanghai Research Institute of Stomatology National Clinical Research Center of Stomatology ShanghaiChina Department of Oral Surgery State Key Laboratory of Military Stomatology&National Clinical Research Center for Oral Diseases&ShaanxiClinical Research Center for Oral DiseasesSchool of StomatologyThe Fourth Military Medical UniversityXfanShaanxi ProvinceChina Medical Team of 66018 PLA Troops BeijingChina

Distraction osteogenesis is an important technique for the treatment of maxillofacial abnormities and defects. However, distraction osteo- genesis may cause the injury of the inferior alveolar nerve. The relationship between distraction rate and nerve degeneration-regeneration shift remains poorly understood. In this study, 24 rabbits were randomly divided into four groups. To establish the rabbit mandibular distraction osteogenesis model, the mandibles of rabbits in distraction osteogenesis groups were subjected to continuous osteogenesis dis- traction at a rate of 1.0, 1.5 and 2.0 mm/d, respectively, by controlling rounds of screwing each day in the distractors. In the sham group, mandible osteotomy was performed without distraction, Pin-prick test with a 10 g blunt pin on the labium, histological and histomorpho- metric analyses with methylene blue staining, Bodian＇s silver staining, transmission electron microscopy and myelinated fiber density of inferior alveolar nerve cross-sections were performed to assess inferior alveolar nerve conditions. At 28 days after model establishment, in the pin-prick test, the inferior alveolar nerve showed no response in the labium to a pin pricks in the 2 mm/d group, indicating a severe dysfunction. Histological and histomorphometric analyses indicated that the inferior alveolar nerve suffered more degeneration and in- juries at a high distraction rate （2 mm/d）. Importantly, the nerve regeneration, indicated by newborn Schwann cells and axons, was more abundant in 1.0 and 1.5 mm/d groups than in 2.0 mm/d group. We concluded that the distraction rate was strongly associated with the inferior alveolar nerve function, and the distraction rates of !.0 and 1.5 mm/d had regenerative effects on the inferior alveolar nerve. This study provides an experimental basis for the relationship between distraction rate and nerve degeneration-regeneration shift during dis- traction osteogenesis, and may facilitate reducing nerve complications dur

关键词： nerve regeneration distraction osteogenesis stress nerve degeneration demyelination nerve histomorphometry inferior alveolar nerve transmission electron microscopy mandible rabbit neural regeneration

First-principle study on the photocatalystic properties of tungsten doped monoclinic bivo4crystallites

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First-principle study on the photocatalystic properties of t...

A cell-based screen for anticancer activity of 13 pyrazolone derivatives

第八届中国功能材料及其应用学术会议

作者： XI Ying jianG Hai-qing JIN Bo shi jian-zhang LEI Tian-ming zhang Zhi-yong School of Technical Physics Xidian University Schoolof Software Northwest University

ISBN: (纸本)9783037859698

In this paper,the photocatalytic properties of W-doped monoclinic BiVO were studied by CASTEP of MS-5.5 software under PWPP based on density function theory(DFT).The results showed that the band gap narrowed and the absorption edge red shifted after 5d atomic orbit of W mixing into the valence band of BiVO crystallites,which could effectively improve the photocatalytic activity of *** calculated results also implied that the photocatalytic properties of monoclinic BiVOcrystallites could be improved bydoping the transition metal with 5d4 orbital.

关键词： Monoclinic BiVO4 W-doped Photocatalytic Properties First-principles

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Chinese Journal of Cancer 2010年第12期29卷 980-987页

作者： Xiao-Hong Wang Xiao-Kun Wang Yong-Ju Liang Zhi shi jian-Ye zhang Li-Ming Chen Li-Wu Fu State Key Laboratory of Oncology in South China Sun Yat-sen University Cancer center Guangzhou Guangdong 510060 P. R. China

Background and Objective: Pyrazolone derivatives were reported to have a potent cytotoxicity against some tumor cells. In the present study, we evaluated the cytotoxic activity of a series of pyrazolone derivatives against four human tumor cell lines including HepG2, OVCAR3, KB, and multidrug resistance (MDR) KBv200 cell lines in vitro and in vivo. Additionally, the structure-activity relationships of these compounds were discussed. Methods: To analyze the antiproliferative potential of the synthesized compounds against several human tumor cell lines, the 50% inhibitory concentration (IC50) values were determined by MTT assay. Besides, the KBv200 cell xenograft experimental model was established and the sensitivity to the pyrazolone compounds was compared between drug-sensitive parental KB cells and MDR KBv200 cells. Results: Of 13 compounds screened, compound 9 presented remarkable anticancer effects, of which IC50 values were (3.24 ± 0.28), (2.58 ± 0.61), (3.81 ± 0.02), and (3.45 ± 0.03) μg/mL in HepG2, OVCAR3, KB and MDR KBv200 cells, respectively (P > 0.05). Furthermore, compound 9 effectively inhibited tumor growth of KBv200 cell xenografts in vivo, the inhibition ratio was 25.37%, 38.43%, and 47.50% for 1.5 mg/kg, 3 mg/kg, and 6 mg/kg of compound 9 groups, respectively. Conclusion: Compound 9 was the most promising antitumor agent in this study.

关键词：吡唑啉酮酮衍生物抗癌活性合成化合物肿瘤细胞株细胞毒性屏幕单元

Machine Learning Models for Genetic Risk Assessment of Infants with Non-syndromic Orofacial Cleft

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Genomics, Proteomics & Bioinformatics 2018年第5期16卷 354-364页

作者： shi-jian zhang Peiqi Meng Jieni zhang Peizeng Jia Jiuxiang Lin Xiangfeng Wang Feng Chen Xiaoxing Wei Beijing Advanced Innovation Center for Food Nutrition and Human Health College of Agronomy and Biotechnology China Agricultural University Department of Orthodontics & Central Laboratory Peking University School and Hospital of Stomatology State Key Laboratory of Plateau Ecology and Agriculture Medical College of Qinghai University

The isolated type of orofacial cleft, termed non-syndromic cleft lip with or without cleft palate(NSCL/P), is the second most common birth defect in China, with Asians having the highest incidence in the world. NSCL/P involves multiple genes and complex interactions between genetic and environmental factors, imposing difficulty for the genetic assessment of the unborn fetus carrying multiple NSCL/P-susceptible variants. Although genome-wide association studies(GWAS)have uncovered dozens of single nucleotide polymorphism(SNP) loci in different ethnic populations, the genetic diagnostic effectiveness of these SNPs requires further experimental validation in Chinese populations before a diagnostic panel or a predictive model covering multiple SNPs can be built. In this study, we collected blood samples from control and NSCL/P infants inHan and Uyghur Chinese populations to validate the diagnostic effectiveness of 43 candidate SNPs previously detected using GWAS. We then built predictive models with the validated SNPs using different machine learning algorithms and evaluated their prediction performance. Our results showed that logistic regression had the best performance for risk assessment according to the area under curve. Notably, defective variants in MTHFR and RBP4, two genes involved in folic acid and vitamin A biosynthesis, were found to have high contributions to NSCL/P incidence based on feature importance evaluation with logistic regression. This is consistent with the notion that folic acid and vitamin A are both essential nutritional supplements for pregnant women to reduce the risk of conceiving an NSCL/P baby. Moreover, we observed a lower predictive power in Uyghur than in Han cases, likely due to differences in genetic background between these two ethnic ***, our study highlights the urgency to generate the HapMap for Uyghur population and perform resequencing-based screening of Uyghur-specific NSCL/P markers.

关键词： Orofacial cleft Genetic risk Folic acid Vitamin A Nutritional intervention

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需求点随机的分批配送VRP模型与算法研究

控制与决策 2017年第2期32卷 213-222页

作者：石建力张锦西南交通大学交通运输与物流学院成都610031

针对城市配送中需求点不确定的现象,在分批配送车辆路径问题中引入随机需求点进行研究.建立带修正的随机规划模型,采用先验优化策略,根据分批配送的特点,在自适应大邻域搜索算法中引入改进的分割插入算子进行求解.在调整的Solomon算例... 详细信息

针对城市配送中需求点不确定的现象,在分批配送车辆路径问题中引入随机需求点进行研究.建立带修正的随机规划模型,采用先验优化策略,根据分批配送的特点,在自适应大邻域搜索算法中引入改进的分割插入算子进行求解.在调整的Solomon算例上进行的测试表明,允许分批配送在大部分算例中的费用低于不允许分批配送的情形.通过分析计算过程中各个算子权重变化,确定性最差删除算子和随机删除算子在求解此类问题时表现较好;贪婪插入算子、后悔插入算子表现较好;而分割插入算子虽然权重较低,但能对解产生质的影响.

关键词：需求点随机分批配送车辆路径问题自适应大邻域搜索先验优化

Transcatheter closure of coronary artery fistula in children

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Chinese Medical Journal 2010年第7期123卷 822-826页

作者： XU Liang XU Zhong-ying jianG shi-liang ZHENG Hong ZHAO shi-hua LING jian zhang Ge-jun WU Wen-hui LI shi-guo HU Hai-bo Department of Radiology Peking Union Medical College Chinese Academy of Medical Sciences Cardiovascular Institute & Fu Wai Hospital Beijing 100037 China

Background Transcatheter closure of coronary artery fistula （CAF） has emerged as a successful alternative to surgery. We described our experiences in 10 children patients who were accepted for transcatheter closure of CAF. Methods Ten children were 3-10 years old （seven males） with CAF who underwent percutaneous transcatheter closure between October 1995 and April 2008. Sites of origin of these fistulas were： right coronary artery in seven, left anterior descending coronary artery in two, and left circumflex coronary artery in one patient. Drainage sites of these fistulas were： right atrium in seven, right ventricle in two and left ventricle in one patient. All of these fistulas were congenital and had only one orificium *** A Cook coil was used in four patients and an Amplatzer patent ductus arteriosus （PDA） occluder was used in six patients. Checking the angiogram after the procedure revealed complete occlusion in nine patients （90%） and minimal residual flow in one （10%） patient. Technical success was achieved in all patients. Follow-up studies at short term showed complete abolition of shunt in all patients with no evidence of recanalization leading to recurrence of shunt. Conclusions Transcatheter therapy using either Cook coil or Amplatzer PDA occluder is suggested to be a safe and effective method of occlusion. The midterm outcome of the intervention for CAF is satisfactory.

关键词： coronary artery fistula transcatheter occlusion Cook coil Amplatzer patent ductus arteriosus occluder

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BZN陶瓷墨水的制备及其性质研究

无机材料学报 2008年第2期23卷 257-261页

作者：施建章汪宏 Werner Jillek 姚熹西安交通大学电子陶瓷与器件教育部重点实验室西安710049 西安电子科技大学技术物理学院西安710071 Electronic Package Laboratory University of Applied Sciences Nurnberg D90489 Germany

采用一种水性多功能有机试剂Sokalan PM70对喷墨打印用Bi_2O_3-ZnO-Nb_2O_5(BZN)微波陶瓷材料的墨水制备及其性质进行了研究,重点讨论了PM70的添加量和BZN固含量对陶瓷墨水的稳定性和粘度的影响,获得了具有较高稳定性和较高固含量的喷... 详细信息

采用一种水性多功能有机试剂Sokalan PM70对喷墨打印用Bi_2O_3-ZnO-Nb_2O_5(BZN)微波陶瓷材料的墨水制备及其性质进行了研究,重点讨论了PM70的添加量和BZN固含量对陶瓷墨水的稳定性和粘度的影响,获得了具有较高稳定性和较高固含量的喷墨打印用BZN陶瓷墨水,并利用MD-E-201H控制系统打印制备了平面电容器.利用Rodenstock RM600S激光厚度测试仪测量了不同条件下喷墨打印所制备的实际电容的厚度分布,讨论了打印脉冲控制参数对打印效果的影响.实验发现,当Sokalan PM70的添加量约为3.2wt%时,陶瓷墨水的稳定性最高,其固含量最高可达48.8wt%.此体系的墨水在驱动电压为10V,输出脉冲宽度为1.5,脉冲周期为800μs左右时可获得较好的打印效果.

关键词：喷墨打印 Sokalan PM70 水基陶瓷墨水 BZN微波陶瓷