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Acta mathematicae Applicatae Sinica 2017年第2期33卷 263-268页

作者： Cheng-hua GAO Fei ZHANG Ru-yun ma Department of mathematics Northwest Normal University Lanzhou 730070 China

In this paper, we consider the existence of positive solutions of second-order periodic boundary value problem where 0 〈 ε 〈 1/2, g ： [0, 2π] →R is continuous, f ： [0, ∞） →R is continuous and λ 〉 0 is a pa... 详细信息

关键词： periodic boundary value problem existence positive solutions sign-changing Green's functions

LegoDroid: flexible Android app decomposition and instant installation

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Science China(Information Sciences) 2023年第4期66卷 155-173页

作者： Yi LIU yun ma Xusheng XIAO Tao XIE Xuanzhe LIU School of Computer Science Peking University Key Laboratory of High Confidence Software Technologies(Peking University) Ministry of Education Institute for Artificial Intelligence Peking University Department of Computer and Data Sciences Case Western Reserve University

Current mobile applications(apps) have become increasingly complicated with increasing features that are represented on the graphical user interface associated with application programming interfaces(APIs) to access backend functionality and data. Meanwhile, apps suffer from the “software bloat” in volume. Some app features may be redundant, with respect to those features(from other apps) that the users already desirably and frequently use. However, the current app release model forces users to download and install a full-size installation package rather than optionally choosing only their desired features. Large-size apps can not only increase the local resource consumption, such as CPU, memory, and energy, but also inevitably compromise the user experience, such as the slow load time in the app. In this article, we first conduct an empirical study to characterize the app feature usage when users interact with Android apps,and surprisingly find that users access only a very small subset of app features. Based on these findings,we design a new approach named Lego Droid, which automatically decomposes an Android app for flexible loading and installation, while preserving the expected functionality with a fast and instant app load. With such a method, a slimmer bundle will be downloaded and host the target APIs inside the original app to satisfy users’ requirements. We implement a system for Lego Droid and evaluate it with 1000 real-world Android apps. Compared to the original full-size apps, apps optimized by Lego Droid can substantially improve the load time by reducing the base bundle and feature bundles by 13.06% and 10.93%, respectively,along with the app-package installation size by 44.17%. In addition, we also demonstrate that Lego Droid is quite practical with evolving versions, as it can produce substantial reusable code to alleviate the developers’ efforts when releasing new app versions.

关键词： performance software bloat instant installation mobile applications program analysis

Fourier Moment Method with Regularization for the Cauchy Problem of Helmholtz Equation

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Communications in mathematical Research 2012年第4期28卷 300-312页

作者： ma yun-yun ma FU-MING School of mathematics Jilin University Changchun 130012

In this paper, we consider the reconstruction of the wave field in a bounded domain. By choosing a special family of functions, the Cauchy problem can be transformed into a Fourier moment problem. This problem is ill-posed. We propose a regularization method for obtaining an approximate solution to the wave field on the unspecified boundary. We also give the convergence analysis and error estimate of the numerical algorithm. Finally, we present some numerical examples to show the effectiveness of this method.

关键词： Fourier moment method Cauchy problem Helmholtz equation regu-larization ill-possedness

荷斯坦奶牛DPP6和PRKN基因的生物信息学及表达规律分析

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西南农业学报 2024年第1期37卷 210-222页

作者：李瑞瑞虎红红冯雪杨文飞马云宁夏大学动物科技学院/宁夏回族自治区反刍动物分子细胞育种重点实验室银川750021 宁夏新澳农牧有限公司宁夏灵武750406

【目的】旨在探究前期GWAS筛选出的与荷斯坦奶牛产奶相关的二肽基肽酶样6(Dipeptidyl Peptidase⁃like 6,DPP6)和E3泛素连接酶基因(Parkin gene,PRKN)的生物学性质及表达特性,为后续验证DPP6和PRKN基因对于荷斯坦奶牛相关调控机制研究提... 详细信息

【目的】旨在探究前期GWAS筛选出的与荷斯坦奶牛产奶相关的二肽基肽酶样6(Dipeptidyl Peptidase⁃like 6,DPP6)和E3泛素连接酶基因(Parkin gene,PRKN)的生物学性质及表达特性,为后续验证DPP6和PRKN基因对于荷斯坦奶牛相关调控机制研究提供基础。【方法】利用ProtParam、Phyre2、NetPhos 3.1等软件分析DPP6和PRKN的理化性质与蛋白结构,并采用实时荧光定量PCR(Real⁃Time quantitative PCR,RT⁃qPCR)检测DPP6和PRKN基因在荷斯坦奶牛的心脏、脾脏、肝脏、肺脏、肾脏、乳腺、子宫、卵巢、瘤胃、黄体10个组织中的表达规律;通过脂多糖(Lipopolysaccharide,LPS)诱导乳腺上皮细胞(bMECs),初步检测DPP6和PRKN基因在炎症反应中的表达模式。【结果】DPP6蛋白编码863个氨基酸,与山羊的亲缘关系最近;PRKN蛋白编码488个氨基酸,其中甘氨酸含量最多,其序列与马鹿的相似性最高,保守型较强。本研究推测2个物种的DPP6和PRKN蛋白可能具有相似的生物学功能,并且2个蛋白均属于不稳定亲水性蛋白。DPP6和PRKN基因在组织中普遍表达。其中,DPP6基因在乳腺、肺脏、脾脏以及肾脏组织中的表达量显著高于其他组织,而PRKN基因在乳腺、肾脏、瘤胃组织中显著高表达。此外,相比于空白对照组,DPP6与PRKN基因均能够在LPS诱导的bMECs中极显著表达(DPP6基因极显著下调,PRKN基因极显著上调)。【结论】DPP6与PRKN基因可能在调控荷斯坦奶牛乳房炎症过程中发挥潜在作用,为后期荷斯坦奶牛DPP6与PRKN两个基因在奶牛bMECs炎症反应相关调控机制研究提供理论依据。

关键词： DPP6 PRKN 乳房炎症荷斯坦奶牛表达规律

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Bishyoscyamine,one unusual dimeric tropane alkaloid from Anisodus acutangulus

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Chinese Chemical Letters 2013年第3期24卷 236-238页

作者： Chang-An Geng yun-Bao ma Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciences

One unusual dimeric tropane alkalolcl, blshyoscyamme, was ISOlated from the roots o! Amsoaus acutangulus, whose structure including the absolute stereochemistry was unambiguously determined based on extensive 1D NMR and 2D NMR, HR-ESI-MS [et]D and CD spectroscopic analyses. To our knowledge, bishyoscyamine is the first example of tropane alkaloid dimer condensed by a C-N bond.

关键词： Anisodus acutangulusBishyoscyamineTropane alkaloid dimers

Synthesis of visible-light-driven TiO_(2) yolk-shell spheres with {001} facets dominated mesoporous shells

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Chinese Chemical Letters 2013年第3期24卷 260-263页

作者： Hui Wang Bi-Li Wang Shu-yun ma Institute of Science PLA University of Science&TechnologyNanjing 21101China

Anatase phase visible-light-driven TiO_(2) yolk-shell spheres with the size of ca.1-2 um have been synthesized with the combination of solvothermal and heat treatment ***,SEM,TEM,XPS,and PL analysis were used to examine structure and properties of the *** N species and Ti3+centers introduced into the as-prepared photocatalyst can enhance the visible light absorption *** mesoporous shell of the prepared photocatalyst,which promotes the pollutant adsorption ability,consists of the high-reactive[001]facets dominated *** to the unique structure,it is also observed that the as-prepared visible-light-driven TiO_(2) yolk-shell spheres exhibit a sunerinr nhnrncatalvtic activity for organic dyes decomposition than the well-known P25.

关键词： Titanium dioxide {001}Facet Photocatalysis Visible light

“Cutting effect” of organoclay platelets in compatibilizing immiscible polypropylene/polystyrene blends

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1614-1620页

作者： Yan ZHU Hai-yun ma Li-fang TONG Zheng-ping FANG MOE Key Laboratory of macromolecular Synthesis and Functionalization Institute of Polymer Composites Zhejiang University Hangzhou 310027 China Department of Blochemical and Chemical Engineermg Ningbo Institute of Technology Zhejiang University Ningbo 315100 China

In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly located in the dispersed PS phase instead of the interface. The dimensions of the dispersed PS droplets are greatly reduced and apparent compatibilization effect still exists, which cannot be explained by the traditional compatibilization mechanism. A novel compatibilization mecha- nism, "cutting" to apparently compatibilize the immiscible PP/PS blends was proposed. The organoclay platelets tend to form a special "knife-like structure" in the PS domain under the shear stress of the continuous PP phase during compounding. The "clay knife" can split the dispersed PS domain apart and lead to the dramatic reduction of the dispersed domain size.

关键词： Compatibilization Organoclay Polymer blends Polypropylene (PP) Polystyrene (PS)

Impact of cropland degradation in the rural-urban fringe on urban heat island and heat stress during summer heat waves in the Yangtze River Delta

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Advances in Climate Change Research 2022年第2期13卷 240-250页

作者： Hong-yun ma Hai-Jun LI Mi ZHANG Xuan DONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)Nanjing University of Information Science and TechnologyNanjing 210044China Jiangxi Meteorological Observatory Nanchang 330046China School of Atmospheric Sciences Nanjing UniversityNanjing 210023China

China has experienced rapid urbanization since the 1980s,which has significantly reduced croplands around *** from transition to urban land,croplands have also experienced degradation into cropland/natural vegetation mosaic in the rural-urban ***,scant attention has been paid to the climatic effect of such land cover change so *** study thus investigated the potential impacts of the conversion from irrigated cropland into the mosaic on regional hot extremes and heat stress by taking the Yangtze River Delta(YRD)as an *** heatwave events in the summer of 2013 and 2017 were simulated using the Weather Research and Forecasting Model(WRF).Three group experiments with various representative land cover scenarios,i.e.,a default setting experiment with outdated land cover(Exp USGS),a control experiment with updated land cover(CTL),and a sensitivity experiment with modified mosaic land cover(Exp MOS),were performed for comparative *** show that CTL using the updated land cover data from China(ChinaLC)reproduced the spatial variation of observed 2-m air temperature and relative humidity better than Exp *** the irrigated cropland was converted into the mosaic,the 2-m temperatures in most areas of the YRD became significantly higher than those in Exp MOS due to the lower albedo and leaf area index(LAI)in the newly emerged mosaic *** land cover change produced a negative contribution to the urban heat island(UHI)intensity,while it had a positive effect on extreme high temperature under heat wave *** suggests a more cautious usage of the traditional definition of the UHI index is required when investigating the heat island effect,because the rural warming around an urban area may expand the heat island and enhance its heat *** the heatwave periods,the high temperature areas in CTL were larger than those in MOS,and the hot day areas increased by an average of 25.9%.Increase in air temperature further

关键词： Cropland degradation Cropland/natural vegetation mosaic Urban heat island Extreme temperature Heat stress

基于电子舌技术与人工口尝综合评价相结合的布洛芬口服液矫味工艺研究

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药学学报 2024年第8期59卷 2404-2411页

作者：苑蕊屈云萍王艳张雅宣钟宛凌樊箫雨沈慧娟马韫楠叶津宏白洁杜守颖北京中医药大学中药学院北京102488 神威药业集团有限公司河北石家庄051430

本实验通过研究不同矫味剂单独使用及联合使用对布洛芬口服液的矫味效果,以优化矫味配方。首先利用电子舌技术广泛筛选矫味剂种类与质量分数,采用人工口尝法并结合AHP-模糊数学法、Box-Behnken设计试验深入综合评价不同矫味剂组合对布... 详细信息

本实验通过研究不同矫味剂单独使用及联合使用对布洛芬口服液的矫味效果,以优化矫味配方。首先利用电子舌技术广泛筛选矫味剂种类与质量分数,采用人工口尝法并结合AHP-模糊数学法、Box-Behnken设计试验深入综合评价不同矫味剂组合对布洛芬口服液的矫味效果,优化矫味配方并进行验证。研究获得了北京中医药大学审查委员会的伦理批准(伦理号:2024BZYLL0102)。结果显示,通过单因素试验分别筛选出矫味剂质量分数与种类,Box-Behnken响应面连用AHP-模糊数学法拟合得到函数模型:Z=688.310 11-3 023.722 22X_(1)-11.477 00X_(2)+62.721 67X_(3)+14.600 00X_(1)X_(2)-179.666 67X_(1)X_(3)-3.152 00X_(2)X_(3)+4 031.111 11X_(1)^(2)+0.525 28X_(2)^(2)+9.772 00X_(3)^(2),该模型稳定可靠,确定矫味的最佳配方为甜菊苷3.9 g·L^(-1),木糖醇100 g·L^(-1),甲基-β-环糊精30 g·L^(-1),验证试验综合评分均值为88.14,RSD为0.39%,具有可行性。本研究通过客观与主观结合实现了布洛芬口服液口感的改善,并建立了3种类型矫味剂联合使用改善药物口感的方法,筛选出布洛芬口服液的最优矫味配方,极大改善了原制剂的口感,提高了患者的顺应性,可为制剂的不良口感改善提供新思路。

关键词：布洛芬口服液矫味剂模糊数学综合评价法层次分析法 Box-Behnken响应面

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中国高水平运动员心电图异常分析

中国运动医学杂志 2024年第5期43卷 356-363页

作者：梁辰何江华高璨张建红李璟马云谢敏豪国家体育总局运动医学研究所北京100061 北京体育大学北京100084

目的:通过对中国高水平运动员进行心电图检查并诊断,评估性别、运动年限和运动类型对运动员心电图改变的影响。方法:对2016年至2019年进行心电图检查的891名中国高水平运动员的心电图进行检测。根据2010年欧洲心脏病学会指南(ESC)将心... 详细信息

目的:通过对中国高水平运动员进行心电图检查并诊断,评估性别、运动年限和运动类型对运动员心电图改变的影响。方法:对2016年至2019年进行心电图检查的891名中国高水平运动员的心电图进行检测。根据2010年欧洲心脏病学会指南(ESC)将心电图分为:组0(正常心电图)、组1(常见与训练相关心电图)、组2(不常见与训练不相关心电图)。分析运动员的性别、训练年限(4~6年、7~10年和≥11年)和运动类型(技巧类、力量类、耐力类、混合类)对各组心电图改变的影响。结果:(1)不常见与训练不相关的心电图改变的发生率在不同性别、不同训练年限和不同训练类型的运动员间均不存在显著性差异。(2)常见与训练相关的心电图改变在男运动员中发生率显著高于女运动员(58.9%vs 47.4%);在训练超过11年运动员中发生率最高,与训练4~6年相比具有显著性差异(P<0.05);在不同运动类型间具有显著差异(P<0.01),在混合类中发生率最高,为64.6%;窦性心动过缓在混合类和耐力类运动中的发生率显著高于其他运动类型(P<0.05)。结论:中国高水平运动员与训练相关的心电图改变与性别、训练年限和运动类型均有关。

关键词：运动员心电图性别训练年限运动类型