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A parameterized geometry design method for inward turning inlet compatible waverider

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Chinese Journal of Aeronautics 2013年第5期26卷 1135-1146页

作者： tian chao Li Ni Gong Guanghong Su Zeya Department of Automation Science and Electrical Engineering Beihang University

Intensive studies have been carried out on generations of waverider geometry and hypersonic inlet geometry. However, integration efforts of waverider and related air-intake system are restricted majorly around the X43A-like or conical flow field induced configuration, which adopts mainly the two-dimensional air-breathing technology and limits the judicious visions of developing new aerodynamic profiles for hypersonic designers. A novel design approach for integrating the inward turning inlet with the traditional parameterized waverider is proposed. The proposed method is an alternative means to produce a compatible configuration by linking the off-the-shelf results on both traditional waverider techniques and inward turning inlet techniques. A series of geometry generations and optimization solutions is proposed to enhance the lift-to-drag ratio. A quantitative but efficient aerodynamic performance evaluation approach （the hypersonic flow panel method） with lower computational cost is employed to play the role of objective function for opti- mization purpose. The produced geometry compatibility with a computational fluid dynamics （CFD） solver is also verified for detailed flow field investigation. Optimization results and other numerical validations are obtained for the feasibility demonstration of the proposed method.

关键词： Hypersonic inlets Hypersonic vehicles Inward turning inlet Optimization Parameterization Waverider

New results on multilevel diversity coding with secure regeneration

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Science China(Information Sciences) 2018年第10期61卷 130-143页

作者： Shuo SHAO Tie LIU chao tian Cong SHEN Department of Electrical Engineering Shanghai Jiaotong University Department of Electrical Engineering Texas A&M University School of Information Science and Technology University of Science & Technology of China

The problem of multilevel diversity coding with secure regeneration is revisited. Under the assumption that the eavesdropper can access the repair data for all compromised storage nodes, Shao et *** a precise characterization of the minimum-bandwidth-regeneration(MBR) point of the achievable normalized storage-capacity repair-bandwidth tradeoff region. In this paper, it is shown that the MBR point of the achievable normalized storage-capacity repair-bandwidth tradeoff region remains the same even if we assume that the eavesdropper can access the repair data for some compromised storage nodes(defined as the type II compromised nodes) but only the data contents of the remaining compromised nodes(defined as the type I compromised nodes), as long as the number of type I compromised nodes is no greater than that of type II compromised nodes.

关键词： distributed storage regenerating code exact repair secrecy constraint MBR point

Understanding the cooperative effects in the catalysis of homodimeric fluoroacetate dehalogenase

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Science China Chemistry 2024年第7期67卷 2382-2391页

作者： Ke-Wei Chen Jia-Nan Chen Jun Zhang chao Wang tian-Yu Sun Yun-Dong Wu Key Laboratory of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Changping Laboratory Beijing 102200China

Fluoroacetate dehalogenases(FAcD),a homodimeric enzyme,catalyzes the conversion of fluoroacetic acid to glycolic acid(GoA).It has been proved that the enzyme has a half-of-the-site ***,its catalytic(C)subunit converts the first substrate to a covalent intermediate;then,the non-catalytic(NC)subunit binds a second substrate and promotes the conversion of the intermediate in the C subunit into the final *** the release of the product,the C subunit becomes the NC subunit,and the previous NC subunit becomes the C *** elucidate the detailed mechanism behind this cooperative catalysis,we have conducted microsecond-scale MD simulations along the reaction *** simulations indicate that the substrate in the NC subunit induces W185 and Y141 adopting an open conformation in the C *** opening of W185(C)facilitates the entry of catalytic water,enhancing the catalytic activity for product formation,while the opening of Y141(C)creates an unfavorable environment for product binding,promoting its *** interaction network analysis reveals that the substrate in the NC subunit can induce conformational changes through a conserved water chain at the interface.

关键词： enzyme catalysis molecular dynamics cooperative effect pre-reaction state

除草剂减量配施增效助剂对杂草防效和春小麦产量的影响

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黑龙江农业科学 2024年第6期 31-36页

作者：代丽婷车京玉张起昌刘宁涛田超尹雪巍姜云峰黑龙江省农业科学院克山分院/黑龙江省春小麦遗传育种工程技术中心黑龙江齐齐哈尔161005

为促进黑龙江省西部地区春小麦草害的农药减量防控和绿色生产,以克春9号为试验材料,通过田间试验,于2022年在克山地区研究除草剂减量与增效助剂激健混施对麦田杂草的防治效果和对小麦产量及产量性状的影响。结果表明,处理2(除草剂减施2... 详细信息

为促进黑龙江省西部地区春小麦草害的农药减量防控和绿色生产,以克春9号为试验材料,通过田间试验,于2022年在克山地区研究除草剂减量与增效助剂激健混施对麦田杂草的防治效果和对小麦产量及产量性状的影响。结果表明,处理2(除草剂减施20%+增效助剂激健)和处理3(除草剂减施40%+增效助剂激健)对药后30 d杂草防治效果较好,二者株防效和鲜重防效最高;处理3产量最高,为5567.22 kg·hm^(-2),与处理1(常规除草剂用量)无显著差异,该处理下有效穗数和千粒重为519.33万穗·hm^(-2)和32.83 g,不孕小穗数最小,为0.23个,与处理2和处理1无显著差异,但与其余两个处理差异显著;相关分析表明,有效穗数、除草剂用量和千粒重对春小麦产量有促进作用,不孕小穗数对春小麦产量有显著负作用。因此,推荐该地区春小麦田除草最佳组合是除草剂减量40%与增效助剂激健混施。

关键词：春小麦除草剂减量激健防治效果产量

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Influences of Charcoal Amendment on Adsorption-Desorption of Isoproturon in Soils

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Agricultural Sciences in China 2010年第2期9卷 257-265页

作者： tian chao WANG Mi-dao SI You-bin School of Sciences Anhui Agricultural University Hefei 230036 P.R.China School of Resources and Environment Anhui Agricultural University Hefei 230036 P.R.China

In order to prevent pesticide leaching from soil, the effects of charcoal amendment on adsorption-desorption of isoproturon in soils were studied and the mechanisms in reducing the loss of isoproturon from soils were suggested. Adsorption-desorption of isoproturon in five different particle sizes of charcoals and three different soils were studied using batch equilibration technique. The results showed that the experimental data were well fitted by the Freundlich empirical equation. Charcoal had a great adsorption capacity for isoproturon, and the smaller the particle size of charcoal, the more the adsorption of isoproturon. The amendment with charcoal could greatly improve the adsorption of isoproturon in soils. The adsorption of isoproturon in soils increased with the rate of charcoal amended （r= 0.9568＊＊, P 〈 0.01）. Desorption of isoproturon from charcoals and soils showed significant hystersis which was shown by the higher adsorption slope （1/nsds） compared to the desorption slope （1/ndes. The hysteresis effects of charcoal on desorption of isoproturon were closely correlated with the content of charcoal in the soils, and the hysteresis index （H） increased with the rate of charcoal amended. Observation of environmental scanning electron microscopy （ESEM） exhibitted the fine pore structure and special surface characteristics of the tested charcoal. Analysis of Fourier transform infrared spectra （FTIR） of isoproturon adsorbed on charcoal suggested probable bonding interactions between isoproturon and charcoal. This research suggests that charcoal amendment may be an effective management practice for controlling pesticide desorption and leaching in soils.

关键词： charcoal amendment isoproturon adsorption desorption soil

Estimation of maximum inclusion by statistics of extreme values method in bearing steel

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Journal of Iron and Steel Research(International) 2017年第11期24卷 1131-1136页

作者： chao tian Jian-hui Liu Heng-chang Lu Han Dong Central Iron and Steel Research Institute Beijing 100081China

A statistic method, statistics of extreme values （SEV）, was described in detail, which can esti mate the size of maximum inclusion in steel. The characteristic size of the maximum inclusion in a high clean bearing steel （GCrl5） was evaluated by this method, and the morphology and corn position of large inclusions found were analyzed by scanning electron microscopy （SEM）. When standard inspection area （S0） is 280 mm2, the characteristic size of the biggest inclusion found in 30 standard inspection area is 23.93 μm, and it has a 99.9% probability of the characteristic size of maximum inclusion predicted being no larger than 36.85μm in the experimental steel. SEM result shows that large inclusions found are mainly composed of CaS, calcium-aluminate and MgO. Compositing widely exists in large inclusions in high clean bearing steel. Compared with traditional evaluation method, SEV method mainly focuses on inclusion size, and the esti- mation result is not affected by inclusion types. SEV method is suitable for the inclusion eval uation of high clean bearing steel.

关键词： Nonmetallic inclusion Statistics of extreme values Gumbel distribution function Likelihood function estimation

加味桂枝茯苓丸治疗痰瘀互结型多囊卵巢综合征患者的效果

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河南医学研究 2024年第10期33卷 1869-1873页

作者：李彦茹李会娟徐广立田超方蕾郭婧景竹青王晶河南中医药大学第一附属医院生殖医学科二区河南郑州450000

目的探讨加味桂枝茯苓丸治疗痰瘀互结型多囊卵巢综合征(PCOS)患者的效果。方法将2020年9月至2022年12月于河南中医药大学第一附属医院就诊的115例痰瘀互结型PCOS患者纳入研究,经过筛查以后最后纳入106例,根据随机数字表法将其分为中药... 详细信息

目的探讨加味桂枝茯苓丸治疗痰瘀互结型多囊卵巢综合征(PCOS)患者的效果。方法将2020年9月至2022年12月于河南中医药大学第一附属医院就诊的115例痰瘀互结型PCOS患者纳入研究,经过筛查以后最后纳入106例,根据随机数字表法将其分为中药组(在基础组的治疗上加用桂枝茯苓丸治疗,53例)和基础组(炔雌醇环丙孕酮片、来曲唑片治疗,53例)。对所有患者一般临床资料和内分泌代谢特征进行分析,并观察两组临床疗效、激素水平变化、月经改善情况和体外受精-胚胎移植(IVF-ET)妊娠结局。结果两组年龄、体重指数(BMI)、腰臀比(WHR)、Ferriman-Gallway(F-G)评分、痤疮综合分级系统(GAGS)评分、左右卵巢体积比较,差异无统计学意义(P>0.05)。中药组治疗总有效率高于基础组(P<0.05)。中药组治疗后血清卵泡刺激素(FSH)、促黄体生成素(LH)、雌二醇(E_(2))、睾酮(T)水平改善均优于基础组;中药组月经各项改善情况均优于基础组,差异有统计学意义(P<0.05);中药组获卵数、成胚数受精率、优胚率和临床妊娠率高于基础组,差异有统计学意义(P<0.05)。结论加用加味桂枝茯苓丸治疗痰瘀互结型PCOS患者,其临床疗效要优于常规治疗,能有效调整LH、T激素水平,改善月经情况和生殖功能,提高受精率、优胚率和妊娠率,值得临床推广。

关键词：多囊卵巢综合征痰瘀互结型桂枝茯苓丸

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月经血源性间充质干细胞来源外泌体对SD大鼠皮肤创面愈合的促进作用及其机制

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山东医药 2024年第8期64卷 33-38页

作者：袁怡君何昱李均邹心如田超贺红林丁娜贺天文刘康川北医学院第二临床医学院(南充市中心医院)妇科四川南充637000 南充市妇幼保健计划生育服务中心妇产科川北医学院第二临床医学院(南充市中心医院)烧伤整形美容外科川北医学院第二临床医学院(南充市中心医院)组织工程与干细胞研究所

目的观察月经血源性间充质干细胞(MenSCs)中分离的外泌体(MenSC-Exos)对SD大鼠皮肤创面愈合的促进作用,并探讨其机制。方法分离培养健康成年女性志愿者的MenSCs,提取MenSC-Exos;将SD大鼠随机分为实验组和对照组,制作背部皮肤机械创面,... 详细信息

目的观察月经血源性间充质干细胞(MenSCs)中分离的外泌体(MenSC-Exos)对SD大鼠皮肤创面愈合的促进作用,并探讨其机制。方法分离培养健康成年女性志愿者的MenSCs,提取MenSC-Exos;将SD大鼠随机分为实验组和对照组,制作背部皮肤机械创面,分别给予MenSC-Exos或PBS治疗;观察创面愈合情况并计算创面愈合率,采用HE染色观察创面炎症细胞浸润情况,免疫荧光法检测M1、M2型巨噬细胞,采用免疫组化法检测创面组织中的白细胞介素(IL)-6、IL-10、新生血管、Ⅰ型胶原蛋白、Ⅲ型胶原蛋白,采用Masson染色检测创面胶原蛋白含量及成熟度。培养成纤维细胞并分成外泌体组和PBS组,分别加入MenSC-Exos或PBS,采用CCK-8法检测细胞增殖能力,划痕实验检测细胞迁移能力。结果实验组术后第7、14天创面愈合率、Ⅲ型胶原蛋白沉积率和胶原蛋白含量高于对照组,Ⅰ型胶原蛋白沉积率低于对照组(P均<0.05)。实验组术后第7天创面炎症细胞数量和M1/M2低于对照组,M2型巨噬细胞数量高于对照组(P均<0.05);与对照组相比,实验组术后第3、7天创面IL-6表达降低,IL-10表达及血管内皮细胞表达升高(P均<0.05)。外泌体组培养1~5 d细胞增殖能力均高于PBS组,外泌体组培养24 h细胞迁移率高于PBS组(P均<0.05)。结论MenSC-Exos能够促进大鼠皮肤创面愈合,机制可能与调节炎症反应、促进血管生成和成纤维细胞增殖、调节胶原重塑有关。

关键词：月经血间充质干细胞外泌体成纤维细胞血管生成伤口愈合

Case Reports of a Giant Cell Reparative Granuloma and a Giant Cell Tumor on Temporal Bone

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Chinese Medical Journal 2018年第18期131卷 2254-2256页

作者： Wei-Ying Dai chao tian Li Liu Department of Radiology Tianjin Huanhu Hospital Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases Tianjin 300350 China

To the Editor： Giant cell reparative granuloma （GCRG） is a nonneoplastic, benign lesion derived from bone tissue. The morbidity of GCRG is relatively low, comprising approximately 7% of benign bone lesions. GCRGs are mostly tbund in adolescents, and no apparent gender inclination has been identified. In addition, GCRGs are predominantly found in the mandible and maxilla; a few cases have occurred in the short bones as the hands and feet. Occasionally, GCRGs are detected in long bones and vertebrae; temporal GCRGs are rarely reported. GCRGs associated with intracranial invasion are rare. Although some cases of GCRG have been previously reported, characteristic and elaborate descriptions have not yet been clearly established for imaging diagnosis and differential diagnosis. This article reported one case of left temporal GCRG associated with cholesteatoma caused by otitis media mastoiditis and another case of temporal giant cell tumor （GCT）.

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