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Mating behavior and sexual selection in a polygamous beetle

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Current Zoology 2013年第2期59卷 257-264页

作者： Wen lu Qiao WANG Mingyi tian Jin XU jian LV Aizhi QIN College of Agriculture Guangxi University Narming 530005 China Institute of Natural Resources Massey University Private Bag 11222 Palmerston North New Zealand College of Natural Resources and Environment South China Agricultural University Guangzhou 510642 China College of Agriculture Yunnan University Kunming 650091 China Library Guangxi University Narming 530005 China

Mating behavior and sexual selection in relation to morphometric traits in a polygamous beetle, Glenea cantor （F.）（Coleoptera： Cerambycidae）, were investigated. Upon encounter, a male approached a female, mounted her, grasped her terminal abdomen with his hind tarsi, and attempted to mate. Successful mating lasted about 3.5 h. Although all traits measured in females and half of traits in males were significantly correlated with mating success, the primary selection on virgin females was the genital trait, thebursa copulatrix length, and that on males was the body length and hind tarsal length. Longer bursa copulatrix accommodated a larger ejaculate, suggesting that this female trait benefits the male that first mates with the female in terms of in- creasing ejaculate size to beat subsequent males in sperm competition. Under a female-biased sex ratio, more than 20% of mat- ings failed within 20s after the male genitalia had been inserted into hers, suggesting that males assess genital features of the re- ：male before insemination and undertake cryptic male mate choice. Larger males were more capable of grasping females and achieving mating. During the premating struggle the male almost always used his hind tarsi to lift the female terminal abdomen to the position for his genitalia to insert, and as a result, males with longer hind tarsi achieved higher mating success [Current Zoolo- gy 59 （2）： 257-264, 2013].

关键词： Bursa Body length Mating behavior Sexual selection Tarsal length

Improved Bag-of-Words Model for Person Re-identification

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Tsinghua Science and Technology 2018年第2期23卷 145-156页

作者： lu tian Shengjin Wang Department of Electronic Engineering Tsinghua University Beijing 100084 China.

Person re-identification(person re-id) aims to match observations on pedestrians from different *** is a challenging task in real word surveillance systems and draws extensive attention from the *** existing methods are based on supervised learning which requires a large number of labeled data. In this paper, we develop a robust unsupervised learning approach for person re-id. We propose an improved Bag-of-Words(i Bo W) model to describe and match pedestrians under different camera views. The proposed descriptor does not require any re-id labels, and is robust against pedestrian variations. Experiments show the proposed i Bo W descriptor outperforms other unsupervised methods. By combination with efficient metric learning algorithms, we obtained competitive accuracy compared to existing state-of-the-art methods on person re-identification benchmarks, including VIPe R, PRID450 S, and Market1501.

关键词： person re-identification bag-of-words unsupervised learning feature fusion

S-box:six-dimensional compound hyperchaotic map and artificial bee colony algorithm

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Journal of Systems Engineering and Electronics 2016年第1期27卷 232-241页

作者： Ye tian Zhimao lu College of Information and Communication Engineering Harbin Engineering University Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngneeringHarbin Normal University Faculty of Electronic Information and Electrical Engineering Dalian University of Technology

Being as unique nonlinear components of block ciphers,substitution boxes（S-boxes） directly affect the security of the cryptographic *** is important and difficult to design cryptographically strong S-boxes that simultaneously meet with multiple cryptographic criteria such as bijection,non-linearity,strict avalanche criterion（SAC）,bits independence criterion（BIC）,differential probability（DP） and linear probability（LP）.To deal with this problem,a chaotic S-box based on the artificial bee colony algorithm（CSABC） is *** uses the S-boxes generated by the six-dimensional compound hyperchaotic map as the initial individuals and employs ABC to improve their *** addition,it considers the nonlinearity and differential uniformity as the fitness functions.A series of experiments have been conducted to compare multiple cryptographic criteria of this algorithm with other *** results show that the new algorithm has cryptographically strong S-box while meeting multiple cryptographic criteria.

关键词： substitution boxes(S-boxes) multiple cryptographic criteria six-dimensional compound hyperchaotic map artificial bee colony algorithm(ABC).

Investigating nuclear dissipation properties at large deformations via excitation energy at scission

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Nuclear Science and Techniques 2016年第6期27卷 33-37页

作者： jian tian Wei Ye Department of Physics Southeast University

Using the stochastic Langevin model coupled with a statistical decay model,we study nuclear dissipation properties at large deformations with excitation energy at scission(E*_(sc)) measured in *** is found that the postsaddle dissipation strength required to fit E*_(sc) data is 12*10^(21) s^(-1)for^(254;256)Fm and 6*10^(21) s^(-1)for^(189)Au,which has a smaller postsaddle deformation than the former heavy nucleus,showing a rise of nuclear dissipation strength with increasing deformation.

关键词：断裂能量核耗散大变形激发能特性测量实验模型 SC

分离纯化重组解脂耶氏酵母发酵液中虫草素的研究

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食品与发酵工业 2025年第1期51卷 26-31页

作者：宋丽萍段希宇王翀卢向阳田云湖南农业大学生物科学技术学院湖南长沙410128 沅江市芦小妹食品有限公司湖南益阳413000

多项研究证明以解脂耶氏酵母作为虫草素生物合成的细胞工厂,是获得虫草素的有效途径。为获得下游虫草素分离纯化工艺,该研究采用不同规格的大孔吸附树脂对重组解脂耶氏酵母发酵液中的虫草素进行静态、动态纯化。结果显示,以NKA-Ⅱ大孔... 详细信息

多项研究证明以解脂耶氏酵母作为虫草素生物合成的细胞工厂,是获得虫草素的有效途径。为获得下游虫草素分离纯化工艺,该研究采用不同规格的大孔吸附树脂对重组解脂耶氏酵母发酵液中的虫草素进行静态、动态纯化。结果显示,以NKA-Ⅱ大孔吸附树脂作为吸附材料,在虫草素质量浓度为3 mg/mL、pH值为9的上样液以上样流速为3 BV/h、上样体积为10 BV、洗杂流速为2 BV/h、洗杂体积为3 BV、洗脱剂为体积分数为30%乙醇、洗脱流速为3 BV/h、洗脱体积为15 BV时,发酵液中虫草素回收率可达到87.67%,纯度达65.82%。该研究为今后利用重组解脂耶氏酵母大规模生产制备虫草素提供数据参考。

关键词：虫草素解脂耶氏酵母分离纯化大孔吸附树脂甘蔗糖蜜

茶叶不同添加方式对太平猴魁绿茶啤酒风味影响

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食品与发酵工业 2025年第1期51卷 81-89页

作者：林睿吴殿辉彭政聪谢广发陆健工业生物技术教育部重点实验室粮食发酵与食品生物制造国家工程研究中心江苏省生物活性制品加工工程技术研究中心江南大学生物工程学院江苏无锡214122 浙江省污染暴露与健康干预重点实验室浙江树人学院生物与环境工程学院浙江杭州310015

绿茶作为辅料增添啤酒风味已被众多研究者们广泛关注,但绿茶的添加方式对啤酒风味的影响鲜有研究。该文将太平猴魁以3种不同投料方式加入到啤酒的发酵中,来研究清香型绿茶投料方式对啤酒挥发性风味物质的影响。采用GC-MS对不同组啤酒的... 详细信息

绿茶作为辅料增添啤酒风味已被众多研究者们广泛关注,但绿茶的添加方式对啤酒风味的影响鲜有研究。该文将太平猴魁以3种不同投料方式加入到啤酒的发酵中,来研究清香型绿茶投料方式对啤酒挥发性风味物质的影响。采用GC-MS对不同组啤酒的风味物进行鉴定分析,通过对多种风味物质的香味活性值(odor activity values,OAV)筛选以及偏最小二乘-判别分析(partial least squares-discriminant analysis,PLS-DA),研究不同工艺下绿茶啤酒的香气组分差异和关键香气组分标记物。结果表明,不同工艺下太平猴魁绿茶啤酒的挥发性成分差异显著(P<0.05)。在太平猴魁绿茶啤酒中,以OAV≥0.1筛选出了20种香气成分,其中β-紫罗兰酮、异戊醛、β-环柠檬醛、蘑菇醇和香茅醇这5种挥发性成分来源于太平猴魁,并且在冷萃的条件下能更多保留这类风味成分,使得啤酒具有更加丰富的风味属性。根据PLS-DA模型进一步筛选得到了9种变量投影重要性值大于1的物质,其中月桂酸乙酯、乙酸苯乙酯、月桂醇、正癸醛和壬醛这类香气化合物对啤酒的清香和花香风味属性具有重要贡献,可作为区分不同工艺下太平猴魁绿茶啤酒的香气组分标记物。

关键词：绿茶啤酒太平猴魁气相色谱-质谱联用挥发性成分偏最小二乘-判别分析

Nonexistence of maximizers for the functional of the centroaffine Minkowski problem

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Science China Mathematics 2018年第3期61卷 511-516页

作者： jian lu Department of Applied Mathematics Zhejiang University of Technology

The centroafhine Minkowski problem is studied, which is the critical case of the L_p-Minkowski problem. It admits a variational structure that plays an important role in studying the existence of *** this paper, we fi... 详细信息

关键词： centroaffine Minkowski problem Monge-Ampere equation variational structure Blaschke-Santalo inequality

Anisotropic inverse harmonic mean curvature flow

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Frontiers of Mathematics in China 2014年第3期9卷 509-521页

作者： jian lu Department of Applied Mathematics Zhejiang University of Technology Hangzhou 310032China

We study the evolution of convex hypersurfaces H（., t） with initial H（., 0） = 0H0 at a rate equal to H - f along its outer normal, where H is the inverse of harmonic mean curvature of H（., t）, H0 is a smooth, closed, and uniformly convex hypersurface. We find a θ^＊〉 0 and a sufficient condition about the anisotropic function f, such that if θ 〉 θ^＊, then H（.,t） remains uniformly convex and expands to infinity as t →∞ and its scaling, H（-, t）e^-nt, converges to a sphere. In addition, the convergence result is generalized to the fully nonlinear case in which the evolution rate is log H - log f instead of H - f.

关键词： Curvature flow parabolic equation asymptotic behavior

New determination of the gravitational constant G

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National Science Review 2020年第12期7卷 1796-1797页

作者： Zheng-tian lu Hefei National Laboratory for Physical Sciences at the Microscale CAS Center for Excellence in Quantum Information and Quantum PhysicsUniversity of Science and Technology of China

A new and so far the most precise determination of the gravitational constant G has been made by Jun luo and colleagues at the Huazhong University of Science and Technology(HUST) [1].The combination of G with two other most fundamental physical constants,the speed of light c and Planck’s constant h,can together construct the natural units(*** units) of time,length and *** relationships inform us that,

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