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Phylogeny and sex chromosome evolution of Palaeognathae

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Journal of Genetics and Genomics 2022年第2期49卷 109-119页

作者： zongji wang Jilin Zhang Xiaoman Xu Christopher Witt Yuan Deng Guangji Chen Guanliang Meng Shaohong Feng Luohao Xu Tamas Szekely Guojie Zhang Qi Zhou MOE Laboratory of Biosystems Homeostasis and Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology Life Sciences InstituteZhejiang UniversityHangzhouZhejiang 310058China Department of Neuroscience and Developmental Biology University of ViennaVienna 1090Austria Institute of Animal Sex and Development Zhejiang Wanli UniversityNingboZhejiang 315100China BGI-Shenzhen Beishan Industrial ZoneShenzhen 518083China Department of Medical Biochemistry and Biophysics Karolinska InstitutetSE-17177 StockholmSweden Department of Biology and the Museum of Southwestern Biology University of New MexicoAlbuquerqueNM 87131USA State Key Laboratory of Biocontrol Department of EcologySchool of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510275China Milner Center for Evolution Department of Biology and BiochemistryUniversity of BathBath BA17AYUK State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Section for Ecology and Evolution Department of BiologyUniversity of CopenhagenDK-2100 CopenhagenDenmark Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China Center for Reproductive Medicine The 2nd Afﬁliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310052China

Many paleognaths(ratites and tinamous) have a pair of homomorphic ZW sex chromosomes in contrast to the highly differentiated sex chromosomes of most other birds. To understand the evolutionary causes for the different tempos of sex chromosome evolution, we produced female genomes of 12 paleognathous species and reconstructed the phylogeny and the evolutionary history of paleognathous sex *** uncovered that Palaeognathae sex chromosomes had undergone stepwise recombination suppression and formed a pattern of “evolutionary strata”. Nine of the 15 studied species’ sex chromosomes have maintained homologous recombination in their long pseudoautosomal regions extending more than half of the entire chromosome length. We found that in the older strata, the W chromosome suffered more serious functional gene loss. Their homologous Z-linked regions, compared with other genomic regions, have produced an excess of species-specific autosomal duplicated genes that evolved female-specific expression, in contrast to their broadly expressed progenitors. We speculate such “defeminization” of Z chromosome with underrepresentation of female-biased genes and slow divergence of sex chromosomes of paleognaths might be related to their distinctive mode of sexual selection targeting females rather than males, which evolved in their common ancestors.

关键词： Paleognaths Sex chromosome evolution Comparative genomics Sexual selection

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螺纹的滚压加工

机械制造 2001年第3期39卷 33-34页

作者：王纵吉山东金马工业集团股份有限公司日照市276826

　　螺纹滚压加工就是用滚压工具进行挤压，使金属塑性变形而形成螺纹的方法。滚压螺纹的金属纤维是连续的，而切削螺纹的金属纤维是断开的，因而滚压螺纹具有如下优点：　　①螺纹表面质量较好，表面粗糙度值较低；　　②提高被加工件... 详细信息

　　螺纹滚压加工就是用滚压工具进行挤压，使金属塑性变形而形成螺纹的方法。滚压螺纹的金属纤维是连续的，而切削螺纹的金属纤维是断开的，因而滚压螺纹具有如下优点：　　①螺纹表面质量较好，表面粗糙度值较低；　　②提高被加工件表层金属的硬度和强度，特别是牙底表面硬度有很大提高；　　③经济效果比切削螺纹提高工效几倍至几十倍，易于实现自动化；　　④滚压螺纹是无屑加工，可节省原材料；　　⑤可加工无法用切削方法加工的细长螺杆。　　正是由于滚压螺纹具有以上优点，因此螺纹滚压加工得到广泛应用。但是在螺纹滚压加工中一付滚丝轮一般只能加工一种规格的螺纹，而滚丝轮需到专业刀具生产厂订做，价格较高。本文从经济的角度出发，阐述如何在滚丝机上实现一付滚丝轮滚压相同螺距、不同规格尺寸系列螺纹的方法。

关键词：螺纹滚压加工滚丝机滚丝轮

Cloud Sphere:一种基于渐进式变形自编码的三维模型表征方法

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图学学报 2024年第6期45卷 1375-1388页

作者：王宗继刘云飞陆峰中国科学院空天信息创新研究院目标认知与应用技术重点实验室网络信息体系技术重点实验室北京100190 北京航空航天大学计算机学院虚拟现实技术与系统国家重点实验室北京100191

针对大数据时代三维模型形状多样性激增的挑战,致力于从形状形成过程中发现独特信息,提出了一种基于球表面逐步变形对三维模型的形状进行统一表征的方法。输入任意三维模型,通过逐步变形自编码网络将一个模板球面点云逐步变形拟合该输... 详细信息

针对大数据时代三维模型形状多样性激增的挑战,致力于从形状形成过程中发现独特信息,提出了一种基于球表面逐步变形对三维模型的形状进行统一表征的方法。输入任意三维模型,通过逐步变形自编码网络将一个模板球面点云逐步变形拟合该输入形状。通过深度神经网络建模三维模型变形过程,从多阶段变形中挖掘独特的形状特征,避免了任务驱动学习方法对人工标注的依赖。通过显式编码形状生成过程中的变形残差,不仅捕捉了最终形状,还记录了形状的渐进变化过程。在深度神经网络的训练方面,采用了多阶段信息监督的方式,提高了变形重建的精度。与当前技术水平代表方法的对比实验表明,多阶段监督训练方式能够增强变形重建结果的细节精度。丰富的消融实验验证了多阶段监督方式的有效性。变形表征方法适用于模型分类、形状迁移、共编辑等计算机图形学应用,具有泛用性,可为三维模型几何属性自动解析与高效编辑提供底层的数据表征方法支持。

关键词：三维表征三维模型变形球面点云模板自编码器深度学习

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浅玫瑰色链霉菌壳聚糖酶罐发酵工艺及其优化

上海海洋大学学报 2015年第6期24卷 952-959页

作者：王剑蒋霞云卢梦琪王宗继李进国王正碧孔仪上海海洋大学食品学院上海201306 上海市水产品加工及贮藏工程技术研究中心上海201306 山东卫康生物医药科技有限公司山东临沂276017

发酵罐装填系数0.6,控制罐压0.08 Mpa,采用单因素试验方法考察搅拌转速、种子液OD600、接种量和通气量4个因素对壳聚糖酶发酵的影响。根据试验结果确定该菌种10 L发酵罐发酵条件：搅拌转速250 r/min,种子液OD600=0.8~1.0,通气量2.0 vvm... 详细信息

发酵罐装填系数0.6,控制罐压0.08 Mpa,采用单因素试验方法考察搅拌转速、种子液OD600、接种量和通气量4个因素对壳聚糖酶发酵的影响。根据试验结果确定该菌种10 L发酵罐发酵条件：搅拌转速250 r/min,种子液OD600=0.8~1.0,通气量2.0 vvm,接种量3%,其发酵周期56 h,酶活力在52 h达到最大,为（35.2±0.5）U/mL。补料工艺发酵周期为64 h,酶活力在60 h达到最大,为（46.4±0.5）U/mL。补料工艺能维持产酶期菌丝形态和延长产酶时间,从而提高产酶,最终补料工艺比批次发酵产酶提高了32%。该研究为壳聚糖酶工业化生产奠定了基础。

关键词：壳聚糖酶发酵工艺链霉菌

On the asymmetric distribution of heat loss from the Earth'sinterior

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Chinese Science Bulletin 1998年第18期43卷 1566-1570页

作者： Yang wang Jiyang wang zongji Ma Institute of Geology Chinese Academy of Sciences Beijing China Institute of Geology State Seismological Bureau Beijing China

Mean heat flows and heat losses of the Northern and Southern hemispheres are calculated using degree 12 spherical harmonic representation of the global heat flow field (Pollack et al., 1993). Mean heat flows and heat losses of 0° hemisphere and 180° hemisphere, with median lines being 0° longitude and 180° longitude, are also calculated. The mean heat flow of the Southern Hemisphere is 99.3 mW·m -2, significantly higher than that of the Northern Hemisphere (74.0 mW·m -2). The mean heat flow of 0° hemisphere (94.1 mW·m -2) is also higher than the value of 180° hemisphere (79.3 mW·m -2). The mantle heat loss from the Southern Hemisphere is 22.1×10 12 W, as twice as that from the Northern Hemisphere ( 10.8×10 12 W). The 16.9×10 12 W mantle heat loss from 0° hemisphere is close to 16.0×10 12 W from 180° hemisphere. The hemispherical asymmetry of global heat loss is originated by the asymmetry of geographic distribution of continents and oceans. The asymmetric distribution of heat loss is a long-term phenomenon in the geological history.

关键词： heat flow heat loss from Earth’s interior Earth’s asymmetry.

Analysis of Rockfall and Its Impact on the Cut-and-Cover Tunnel in Dynamics

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 905-909页

作者： SONG Shuzhi KONG Jiming wang Chenghua CHENG Zefu YANG zongji Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 SichuanChina Graduate University of Chinese Academy of Sciences Beijing 100049 China

This paper presents the effect of thickness of Buffer layer on the safety of cut-and-cover tunnel under the given magnitude and height of rockfall, and the limit load of the structure. To establish calculating models of rockfall in different conditions, the dynamics of the fall down to the surface of the slope is taken into account and the exterior characteristics of the rockfall is analyzed. We have derived the formula for calculating velocity of rocks before and after collision, calculated the impact load upon the structures below and the limit load, and compared the impact force and limit load to judge the safety of the structure. Finally, the validity of models is approved by the safety evaluation of cut-and-cover tunnel in the mouth of Heshang Mountain in Nandan County.

关键词： rockfall cut-and-cover tunnel (CCT) impact force buffer layer

Sliding mode disturbance observer-based backstepping control for a transport aircraft

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Science China(Information Sciences) 2014年第5期57卷 228-243页

作者： ZHANG Chao CHEN zongji WEI Chen Science and Technology on Aircraft Control Laboratory Beihang University School of Automation Science and Electrical Engineering Beihang University

This paper presents a novel control method by integrating the sliding mode disturbance observerbased control and the backstepping control technique,and successfully applies it to a flight control system for heavy cargo airdrop *** super-twisting second order sliding mode disturbance observer(SOSMDO)is employed to estimate bounded but otherwise arbitrary disturbances,thus ensuring asymptotic convergence of the estimation error to zero in a finite ***,the integrated controller can significantly improve the robustness of the flight control system to modeling uncertainty and external disturbance in the presence of state/control *** closed-loop stability is guaranteed in the sense of *** addition,the proposed approach can considerably reduce design *** performance of the proposed control method is demonstrated in a very low altitude extraction airdrop simulation with a high-fidelity six-degree-of-freedom transport aircraft model.

关键词： backstepping sliding mode disturbance observer flight control heavy cargo airdrop uncertainty estimation

Mission decision-making method of multi-aircraft cooperatively attacking multi-target based on game theoretic framework

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Chinese Journal of Aeronautics 2016年第6期29卷 1685-1694页

作者： Yao Zongxin Li Ming Chen zongji Zhou Rui Shenyang Aircraft Design and Research Institute Shenyang 110035China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China

Coordinated mission decision-making is one of the core steps to effectively exploit the capabilities of cooperative attack of multiple aircrafts. However, the situational assessment is an essential base to realize the mission decision-making. Therefore, in this paper, we develop a mission decision-making method of multi-aircraft cooperatively attacking multi-target based on situational assessment. We have studied the situational assessment mathematical model based on the Dempster-Shafer(D-S) evidence theory and the mission decision-making mathematical model based on the game theory. The proposed mission decision-making method of antagonized airfight is validated by some simulation examples of a swarm of unmanned combat aerial vehicles(UCAVs)that carry out the mission of the suppressing of enemy air defenses(SEAD).

关键词： Antagonized airfight D-S evidence theory Fuzzy mapping function Game theoretic framework Mission decision-making Multi-aircraft coordination Situational assessment

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壳寡糖对酸乳发酵特性及感官品质的影响

乳业科学与技术 2017年第4期40卷 6-10页

作者：纪小敏葛家珲韩姝葶王婷婷王宗继李进国毛学英中国农业大学食品科学与营养工程学院北京100083 山东卫康生物医药科技有限公司山东省壳寡糖工程技术研究中心山东临沂276017

以壳寡糖质量浓度不同的酸乳为研究对象,探究壳寡糖对酸乳发酵特性及感官品质的影响。以pH值、滴定酸度、乳酸菌总数和流变特性为指标,研究壳寡糖对酸乳发酵特性的影响;以色泽、气味、组织状态和滋味为指标,评价壳寡糖对酸乳感官品质的... 详细信息

以壳寡糖质量浓度不同的酸乳为研究对象,探究壳寡糖对酸乳发酵特性及感官品质的影响。以pH值、滴定酸度、乳酸菌总数和流变特性为指标,研究壳寡糖对酸乳发酵特性的影响;以色泽、气味、组织状态和滋味为指标,评价壳寡糖对酸乳感官品质的影响。结果表明:壳寡糖质量浓度为50 mg/mL时,酸乳发酵过程中的滴定酸度值与对照组无显著差异(P>0.05),壳寡糖质量浓度为0~100 mg/mL时,酸乳发酵过程中的pH值变化与对照组相似(P>0.05);随着壳寡糖添加量的进一步提高,壳寡糖酸乳在相同发酵时间内与对照组样品相比具有更低的滴定酸度、乳酸菌总数和更高的pH值(P0.05),且具有较优的风味。因此酸乳中壳寡糖的质量浓度为0~100 mg/mL时对酸乳的发酵特性和感官品质无不良影响,可将其应用于酸乳生产。

关键词：壳寡糖酸乳发酵特性感官品质