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面向点击通过率预测的交互边选择算法研究

重庆邮电大学学报（自然科学版） 2023年第3期35卷 554-562页

作者：陈乔松曹凤江泳锋由博文孙开伟邓欣王进朴昌浩重庆邮电大学计算机科学与技术学院重庆400065 重庆邮电大学自动化学院/工业互联网学院重庆400065

点击通过率(click-through rate,CTR)作为推荐系统中必不可少的核心任务分支,提高其预测准确性,既能改善用户的浏览体验,也能为平台增加收益。以往模型在对点击通过率进行建模预测时,保留所有的交互特征存在信息冗余,交互低效等问题。... 详细信息

点击通过率(click-through rate,CTR)作为推荐系统中必不可少的核心任务分支,提高其预测准确性,既能改善用户的浏览体验,也能为平台增加收益。以往模型在对点击通过率进行建模预测时,保留所有的交互特征存在信息冗余,交互低效等问题。针对这一问题提出了一种面向点击通过率预测的交互边选择模型,通过自动识别冗余信息来动态选择有益的交互特征,主要由交互边选择网络层,图节点相似度注意力层构成。交互边选择网络层引入过滤阈值机制并结合动态关联矩阵来去除冗余信息,图节点相似度注意力层通过学习相似度权重矩阵来解决节点过度平滑问题。在Criteo和Avazu两个公开数据集上的大量实验证明,该模型的预测能力优于已有模型。

关键词：点击通过率注意力交互边选择网络图节点相似度

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小角激光光散射法测定聚甲基丙烯酸-6-磺己基钠特性粘数-分子量关系

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高分子通讯 1983年第6期 463-467页

作者：陈竹生陈慧英郭海青朴昌浩北京大学化学系北京大学化学系石油勘探开发科学院钻井所

聚甲基丙烯酸己磺酸钠(PSSHMA)是我们最近合成的,具有较好的抗凝血性能。对于带磺酸基聚合物抗凝血性能的研究,文献报道还不多。我们用羟基己磺酸钠与甲基丙烯酸反应制备了甲基丙烯酸己磺酸钠(SSHMA)新单体,在此异相酯化反应中,使用了... 详细信息

聚甲基丙烯酸己磺酸钠(PSSHMA)是我们最近合成的,具有较好的抗凝血性能。对于带磺酸基聚合物抗凝血性能的研究,文献报道还不多。我们用羟基己磺酸钠与甲基丙烯酸反应制备了甲基丙烯酸己磺酸钠(SSHMA)新单体,在此异相酯化反应中,使用了四丁基硫酸氢铵(TBAB)作为催化剂,使反应较顺利的进行,得纯单体。经复钙时

关键词：甲基丙烯酸磺酸钠马丁烯酸水溶液体系特性粘数特性粘度小角激光光散射己基

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毛囊类器官研究:现状、问题与前景

中国组织工程研究 2025年第31期29卷 6733-6742页

作者：王钊龚琳朴永君大连医科大学附属第一医院皮肤科辽宁省大连市116000

背景:毛囊体外重建依赖于毛乳头细胞及角质形成细胞3D共培养时的自组装行为,该过程与毛囊胚胎发育极为相似,因此,毛囊类器官可作为毛囊再生相关基础研究良好的体外模型,目前,通过仿生系统培养的全人源毛囊类器官已能成功移植到动物体内... 详细信息

背景:毛囊体外重建依赖于毛乳头细胞及角质形成细胞3D共培养时的自组装行为,该过程与毛囊胚胎发育极为相似,因此,毛囊类器官可作为毛囊再生相关基础研究良好的体外模型,目前,通过仿生系统培养的全人源毛囊类器官已能成功移植到动物体内。毛囊类器官研究使毛囊再生成为可能,但构建方法亦无统一定论,仍面临诸多挑战。目的:综述目前毛囊类器官的研究进展,总结毛囊类器官培养方法及表征,阐述应用前景,为后续研究提供可靠依据,以期促进其在组织工程及脱发治疗的临床转化。方法:应用计算机在中国知网(CNKI)及PubMed数据库中,以“毛囊再生,毛发再生,类器官”为中文检索词,“hair growth,hair loss,hair regeneration,hair follicle,dermal papilla cell,organoid”为英文检索词进行检索,查阅国内外关于毛囊类器官的相关文献,共纳入文献67篇进行后续分析。结果与结论:①不同来源的毛乳头细胞与角质形成细胞可在体外构建毛囊类器官,以获得鼠源、人-鼠嵌合及人源毛囊类器官,并成功用于啮齿动物移植模型;②多种重编程方法如电刺激、添加重组蛋白、解离细胞基因过表达等可用于促进毛囊类器官毛胚形成及毛钉伸长,同时,多种3D打印技术的应用已实现大小可控毛囊类器官的批量生产,极大提高了生产效率;③在解离细胞共培养体系中加入黑素细胞时,或可破译新生毛囊的色素缺失难题,而加入人脐静脉血管内皮细胞时,细胞聚集体内的新生血管可改善营养供给,减少中心部位坏死;④随着工程化类毛囊技术逐渐趋于成熟,患者自体细胞构建的毛囊类器官或可用于严重脱发的个体化医疗。

关键词：脱发毛囊再生毛乳头细胞毛囊类器官上皮-间充质交互作用 3D培养类器官组织工程工程化类器官

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Pre-inflation and trans-Planckian censorship

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 27-35页

作者： Yong Cai YunSong piao School of Physics University of Chinese Academy of SciencesBeijing 100049China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China

We investigate the implication of trans-Planckian censorship conjecture(TCC)for the initial state of primordial *** is possible to set the state of perturbation modes in the infinite past as the Minkowski vacuum,only if the pre-inflationary era is *** calculate the evolution of the perturbation modes in such a pre-inflationary era and show that at the beginning of inflation the perturbation modes with wavelengths much shorter than the Hubble scale(but still larger than the Planck length scale)will behave as they are in the Bunch-Davis ***,a past-complete pre-inflationary evolution may automatically prepare the initial state required for the inflationary perturbations at the CMB window while obeying the TCC.

关键词： inflation primordial perturbation trans-Planckian censorship conjecture

Pseudo almost periodic solutions for the systems of differential equations with piecewise constant argument [t + 1/2]

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Science China Mathematics 2004年第1期47卷 31-38页

作者： piao Daxiong Department of Mathematics Ocean University of China Qingdao 266071 China

In this paper we investigate the existence and uniqueness of pseudo almost periodic solutions and unboundedness of other solutions for the systems of differential equations with piecewise constant argument [t + 1/2] by means of new notion of pseudo almost periodic vector sequences. The case in which the characteristic equation has multiple roots is considered.

关键词： pseudo almost periodic functions, pseudo almost periodic vector sequences, piecewise constant arguments, ergodic perturbation.

An Experimental Study on the Phenomena inside the Burning Aviation Kerosene Droplet

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Journal of Thermal Science 2021年第6期30卷 2202-2213页

作者： HE Ming piao Ying School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper conducted an experimental study of droplet behavior characteristics occurring within a burning aviation kerosene droplet and on the droplet *** droplet combustion was performed in a quiescent high-temperature environment by means of the droplet suspension *** soot particles were used as tracers to visualize the fluid motion in the *** shape variation of droplet,internal flow pattern in the burning droplet,and instabilities at gas-liquid phase interface were recorded by a high speed *** internal fluid flow in the droplet was revealed to be caused by the Marangoni effect,which was generated because of the surface tension gradient induced by the temperature gradient on the droplet *** studies showed that the Marangoni effect has a significant impact on the internal *** amplitude of the capillary waves on the surface of the droplet was non-uniform and presented the amplitude characteristics of *** wavelength of the capillary waves for burning aviation kerosene droplet ranged from 110μm to 120μm.

关键词： droplet combustion internal flow Marangoni effect capillary waves

基于顶空-气相色谱-离子迁移谱探究不同成熟期番茄果实风味的差异

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食品科学 2025年第2期46卷 138-147页

作者：付小辉施露孙清珍董晓星朴凤植杜南山河南农业大学园艺学院河南郑州450046 江苏省食品质量安全重点实验室江苏省农业科学院农产品质量安全与营养研究所江苏南京210014

以野生型番茄‘Alisa Craig’为试材,采用高效液相色谱和顶空-气相色谱-离子迁移谱等方法,从代谢和转录水平分析挥发性代谢物质在绿熟期、转色期、坚熟期和完熟期4个成熟阶段的变化趋势。结果表明:随果实成熟,柠檬酸、番茄红素及β-胡... 详细信息

以野生型番茄‘Alisa Craig’为试材,采用高效液相色谱和顶空-气相色谱-离子迁移谱等方法,从代谢和转录水平分析挥发性代谢物质在绿熟期、转色期、坚熟期和完熟期4个成熟阶段的变化趋势。结果表明:随果实成熟,柠檬酸、番茄红素及β-胡萝卜素的含量逐渐增加,苹果酸和β-隐黄质含量则逐渐降低。番茄果实在4个时期共检测到81种挥发性代谢物质,这些物质的总量呈以下规律:完熟期>坚熟期>转色期>绿熟期。进一步将筛选到的40种差异代谢物与品质指标进行相关性分析,发现番茄红素与挥发性代谢物质6-甲基-5-庚烯-2-酮呈正相关。此外,叶绿素降解相关基因SlSGR1、类胡萝卜素代谢相关基因SlPSY1在转色期表达量骤增,与(E)-2-己烯醛变化趋势相似,类胡萝卜素代谢相关基因SlLCYb和SlBCH2则均在完熟期表达量最高,与6-甲基-5-庚烯-2-酮的变化趋势一致。进一步推测,番茄果实在成熟过程中可能通过调控类胡萝卜素代谢相关基因的表达,从而改变果实风味。研究结果将有助于全面了解番茄果实成熟的内在物质基础,为果实成熟过程风味的代谢调控以及改善果实品质提供新的理论依据。

关键词：番茄成熟期品质挥发性化合物

Use of 25-hydroxyvitamin D_(3) in diets for sows:A review

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Animal Nutrition 2021年第3期7卷 728-736页

作者： Lianhua Zhang Xiangshu piao State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Dietary supplementation with 25-hydroxyvitamin D_(3)(25OHD_(3)),as an alternative source of vitamin D,is becoming increasingly popular due to its commercialization and more efficient *** addition of 25OHD_(3)rather than its precursor vitamin D_(3)can circumvent the 25-hydroxylation reaction in the liver,indicating that supplementation of 25OHD_(3)can rapidly improve the circulating vitamin D status of *** experiments have reported that maternal 25OHD_(3)supplementation could increase sow performances and birth outcomes and promote circulating vitamin D status of sows and their *** milk fat content was observed in many experiments;however,others demonstrated that adding 25OHD_(3)to lactating sow diets increased the contents of milk protein and *** an inconsistency between the results of different experiments exists,these studies suggested that maternal 25OHD_(3)supplementation could alter milk composition via its effects on the mammary *** studies have demonstrated that adding 25OHD_(3)to sow diets could improve the mRNA expressions of insulin-induced gene 1(INSIG1)and sterol regulatory element-binding protein 1(SREBP1)in the mammary gland cells from milk and increase the mRNA expressions of acetyl-CoA carboxylaseα(ACCα)and fatty acid synthase(FAS)in the mammary gland *** 25OHD_(3)supplementation promotes skeletal muscle development of piglets before and after parturition,and improves bone properties including bone density and bone breaking force in lactating sows and their ***,25OHD_(3)supplementation in sow diets could improve neonatal bone development via regulation of milk fatty acid composition related to bone metabolism and *** this review,we also discuss the effects of adding 25OHD_(3)to sow diets on the gut bacterial metabolites of suckling piglets,and propose that butyrate production may be associated with bone ***,to better understand

关键词： 25-Hydroxyvitamin D3 Milk composition Skeletal muscle Bone quality Bacterial metabolite

Different dietary protein sources influence growth performance,antioxidant capacity,immunity,fecal microbiota and metabolites in weaned piglets

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Animal Nutrition 2022年第1期8卷 71-81页

作者： Lianhua Zhang Xiangshu piao State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing100193China

The inclusion of high-quality proteins are commonly used in swine *** research investigated the effects of hydrolyzed wheat protein(HWP),fermented soybean meal(FSBM),and enzyme-treated soybean meal(ESBM)on growth performance,antioxidant capacity,immunity,fecal microbiota and metabolites of weaned piglets.A total of 144 piglets(weaned at 28 d)were allotted to 3 dietary treatments with 6 replicate pens per treatment and 8 piglets per *** study included 2 periods:d 0 to14 for phase 1 and d 15 to 28 for phase *** treatments contained 15.90%HWP,15.80%FSBM,and 15.10%ESBM in phase 1,and 7.90%HWP,7.80%FSBM,and 7.50%ESBM in phase 2,*** ADG of piglets in ESBM was increased(P<0.05)compared with HWP and FSBM during d *** with HWP and FSBM,ESBM increased(P<0.05)the ferric reducing ability of plasma(FRAP),and the serum level of superoxide dismutase(SOD)in piglets on d 14,as well as increased(P<0.05)the serum FRAP level in piglets on d *** decreased(P<0.05)serum levels of DAO and IL-1b in piglets compared with HWP on d *** enhanced(P<0.05)the relative abundance of Bacteroidetes,Oscillospiraceae and Christensenellaceae,as well as reduced the relative abundance of Clostridiaceae in the feces compared with HWP and *** PICRUSt analysis revealed that the number of gene tags related to degradation of valine,leucine and isoleucine,as well as lysine degradation in ESBM were lower(P<0.05)than that in HWP and *** increased(P<0.05)the fecal butyrate level in piglets compared with FSBM,and ESBM tended to decrease(P=0.076)the fecal cadaverine ***,ESBM had advantages over HWP and FSBM in improving antioxidant status,immune function,fecal bacteria and metabolites for weaned piglets.

关键词： Protein source Antioxidant capacity Immunity Bacterial community Metabolites Piglet