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L-甲硫氨酸改性微晶纤维素对革兰氏阳性菌的抑制作用

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食品科学 2025年第3期46卷 74-82页

作者：吴思邈杨海凡梁冠男孙昕炀南京财经大学食品科学与工程学院北京绿邦环保工程有限公司

为有效预防、处理食品中的微生物污染，本研究以微晶纤维素（microcrystalline cellulose,MCC）为原材料，通过L-甲硫氨酸（L-methionine,L-Met）负载，制备得到了具有抗菌效果的L-Met改性MCC(M-MCC)。通过微观形貌、元素组成分析等表... 详细信息

为有效预防、处理食品中的微生物污染，本研究以微晶纤维素（microcrystalline cellulose,MCC）为原材料，通过L-甲硫氨酸（L-methionine,L-Met）负载，制备得到了具有抗菌效果的L-Met改性MCC(M-MCC)。通过微观形貌、元素组成分析等表征改性后M-MCC的形貌变化、元素变化以及稳定性，证明了L-Met成功接枝。对M-MCC的体外抗氧化能力进行研究，发现其对2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)（2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS）阳离子自由基有良好的去除效果，当M-MCC的质量浓度为20 mg/mL时，对ABTS阳离子自由基的清除率达到97.47%。而后通过最小抑菌浓度以及细菌生长曲线对M-MCC抑制单核细胞增生李斯特菌（Listeria monocytogenes）、金黄色葡萄球菌（Staphylococcus aureus）的效果进行研究。确定了M-MCC对L. monocytogenes和S. aureus等革兰氏阳性菌有着较好的抑制效果，最小抑菌浓度和最小杀菌浓度分别为15 mg/mL和30 mg/mL。最后，以***和***为指示菌，研究了M-MCC对指示菌细胞膜通透性、细胞膜完整性、细胞内容物以及DNA含量等多个方面的影响。相关结果表明，M-MCC处理对L. monocytogenes和S. aureus的生长有显著的抑制效果，到达对数生长期的时间相较无处理组有所推迟。相应的胞外电导率、核酸和蛋白质的含量都有着明显的变化，且与处理时间密切相关。本研究表明M-MCC在抗菌应用方面具有巨大潜力。

关键词：纤维素氨基酸抑菌单核细胞增生李斯特菌金黄色葡萄球菌

富血小板纤维蛋白复合甲基丙烯酰化明胶水凝胶的促成骨性能

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中国组织工程研究 2025年第4期29卷 809-817页

作者：赵红霞孙政伟韩阳吴学超韩静沈阳药科大学制药工程学院辽宁省沈阳市110016 山东大学制药工程山东省烟台市264000 沈阳药科大学中药学院辽宁省沈阳市110016 华中农业大学生命科学与技术学院湖北省武汉市430070 沈阳药科大学功能食品与葡萄酒学院辽宁省沈阳市110016

背景:富血小板纤维蛋白具有制备简单、制作费用低、安全性高等诸多优势,目前已被广泛应用于口腔颌面外科骨缺损修复研究中,但存在降解速度太快、生长因子释放时间短等问题。目的:将富血小板纤维蛋白负载于甲基丙烯酰化明胶水凝胶内,通... 详细信息

背景:富血小板纤维蛋白具有制备简单、制作费用低、安全性高等诸多优势,目前已被广泛应用于口腔颌面外科骨缺损修复研究中,但存在降解速度太快、生长因子释放时间短等问题。目的:将富血小板纤维蛋白负载于甲基丙烯酰化明胶水凝胶内,通过体内外实验分析其促成骨性能。方法:①抽取新西兰大白兔静脉血,制备富血小板纤维蛋白。分别制备含0,0.05,0.075,0.1 g富血小板纤维蛋白的甲基丙烯酰化明胶水凝胶,分别记为GelMA、GelMA/PRF-0.05、GelMA/PRF-0.075、GelMA/PRF-0.1,表征水凝胶的微观形貌与体外缓释性能。②将4种水凝胶分别与MC3T3-E1细胞共培养,以单独培养的细胞为对照,检测细胞增殖活性;成骨诱导后,检测细胞碱性磷酸酶活性、矿化能力、成骨相关基因(骨钙素、骨桥蛋白、RUNX2)mRNA与蛋白表达,ERK1/2-p38 MAPK通路蛋白mRNA与蛋白表达。③取15只新西兰大白兔。在每只兔颅骨部分别制备4个直径8 mm的全层骨缺损,其中1处缺损不植入任何材料(空白对照组),另3处缺损分别植入GelMA水凝胶、富血小板纤维蛋白、GelMA/PRF-0.1水凝胶。术后4,8,12周,进行骨缺损部位Micro-CT扫描与骨组织形态观察。结果与结论:①扫描电镜下可见4组水凝胶都具有蜂窝状的孔隙结构,并且随着水凝胶中富血小板纤维蛋白含量的增加,水凝胶的孔径轻微减小,但组间比较无明显差异;3组GelMA/PRF水凝胶均能以一定的速率释放转化生长因子β1与胰岛素样生长因子1,随着时间的延长,转化生长因子β1与胰岛素样生长因子1累计释放量显著增加。②CCK-8检测与活/死染色显示,3组GelMA/PRF水凝胶可促进MC3T3-E1细胞的增殖;碱性磷酸酶染色、茜素红染色及成骨基因检测结果显示,GelMA/PRF水凝胶可促进MC3T3-E1细胞的成骨分化,同时可抑制ERK1/2-p38 MAPK通路蛋白的表达,并且呈现富血小板纤维蛋白含量依赖性。③Micro-CT扫描显示,GelMA/PRF-0.1水凝胶组兔骨缺损处骨矿物质密度与骨体积分数均高于其他3组(P<0.05);苏木精-伊红染色显示,相较于其他3组,GelMA/PRF-0.1水凝胶组兔骨缺损处新骨形成更快、更成熟。④结果表明,GelMA/PRF水凝胶在体内外均具有良好的促成骨性能,该作用可能与抑制ERK1/2-p38 MAPK通路蛋白表达有关。

关键词：骨损伤富血小板纤维蛋白甲基丙烯酰化明胶水凝胶颅骨缺损

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数据库管理系统模糊测试技术研究综述

软件学报 2025年第1期36卷 399-423页

作者：梁杰吴志镛符景洲朱娟姜宇孙家广清华大学软件学院湖北文理学院物理与电子工程学院

数据库管理系统(DBMS)是用于高效存储、管理、分析数据的基础软件,在现代数据密集型应用中起着举足轻重的作用.数据库管理系统中存在的漏洞则对数据的安全性和应用的正常运行造成巨大威胁.模糊测试是当前最为流行的动态漏洞检测技术之一... 详细信息

数据库管理系统(DBMS)是用于高效存储、管理、分析数据的基础软件,在现代数据密集型应用中起着举足轻重的作用.数据库管理系统中存在的漏洞则对数据的安全性和应用的正常运行造成巨大威胁.模糊测试是当前最为流行的动态漏洞检测技术之一,它已经被应用于分析DBMS,并发现许多漏洞.分析DBMS的测试需求和难点,提出对DBMS进行模糊测试的一般框架,同时分析DBMS模糊测试工具面临的挑战和需要支持的维度;接着从挖掘不同类型漏洞的角度介绍典型的DBMS模糊测试工具;然后总结包括SQL表达式合成、代码覆盖追踪、测试准则构建在内的DBMS模糊测试的关键技术.接着就测试的覆盖率,生成测试用例的语法语义正确性和漏洞的发现能力对当前的几个流行模糊测试工具进行评估.最后,讨论当前DBMS模糊测试技术研究和实践中面临的问题,并对未来的研究方向进行展望.

关键词：数据库管理系统模糊测试漏洞挖掘

Systematical identification of regulatory GPCRs by single-cell trajectory inference reveals the role of ADGRD1 and GPR39 in adipogenesis

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Science China Life Sciences 2025年

作者： Chuan Ye Xuemei Wang Jun Lin Chenyang wu Yuhua Gao Chenghao Guo Yunxi Liao Ziyan Rao Shaodong Huang Weixuan Chen Ying Huang Jinpeng sun Dongyu Zhao Changtao Jiang Center of Basic Medical Research Institute of Medical Innovation and ResearchPeking University Third Hospital Department of Physiology and Pathophysiology School of Basic Medical SciencesPeking University Department of Biomedical Informatics School of Basic Medical SciencesPeking University State Key Laboratory of Vascular Homeostasis and Remodeling Peking University Center for Obesity and Metabolic Disease Research School of Basic Medical SciencesPeking University State Key Laboratory of Female Fertility Promotion Center for Reproductive MedicineDepartment of Obstetrics and GynecologyPeking University Third Hospital National Clinical Research Center for Obstetrics and Gynecology Peking University Third Hospital Department of Endocrinology and Metabolism Peking University Third Hospital Key Laboratory Experimental Teratology of the Ministry of Education Department of Biochemistry and Molecular BiologySchool of Basic Medical SciencesCheeloo College of MedicineShandong University Department of Immunology School of Basic Medical SciencesPeking University

Adipogenesis is the healthy expansion of white adipose tissue (WAT),serving as a compensatory response to maintain metabolic homeostasis in the presence of excess energy in the ***,the identification of novel regulatory molecules in adipogenesis,specifically membrane receptors such as G protein-coupled receptors (GPCRs),holds significant clinical *** receptors can serve as viable targets for pharmaceuticals,offering potential for restoring metabolic homeostasis in individuals with *** utilized trajectory inference methods to analyze three distinct single-nucleus sequencing (sNuc-seq) datasets of adipose tissue and systematically identified GPCRs with the potential to regulate *** verification in primary adipose progenitor cells (APCs) of mice,we discovered that ADGRD1 promoted the differentiation of APCs,while GPR39 inhibits this *** the obese mouse model induced by a high-fat diet(HFD),both gain-of-function and loss-of-function studies validated that ADGRD1 promoted adipogenesis,thereby improving metabolic homeostasis,while GPR39 inhibited adipogenesis,leading to metabolic ***,through the analysis of 2,400 ChIP-seq data and 1,204 bulk RNA-seq data,we found that the transcription factors (TFs) MEF2D and TCF12 regulated the expression of ADGRD1and GPR39,*** study revealed the regulatory role of GPCRs in adipogenesis,providing novel targets for clinical intervention of metabolic dysfunction in obese patients.

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Advanced high-pressure transport measurement system integrated with low temperature and magnetic field

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Chinese Physics B 2018年第7期27卷 91-99页

作者： jing Guo Qi wu Liling sun Institute of Physics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China

We briefly introduce a new high-pressure transport measurement system integrated with low temperature and magnetic field that is being established as one of the user experimental stations of the Synergetic Extreme Condition User Facilities in the Huairou District of Beijing, China. To demonstrate the capabilities of the system for condensed matter research, the emergence of some pressure-induced phenomena and physics related to superconductivity found previously is also introduced, and then a perspective for such an advanced high-pressure system is presented.

关键词： high pressure low temperature magnetic field superconductivity

混合动力电动汽车能量及驱动系统的关键控制问题研究进展

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山东大学学报(工学版) 2011年第5期41卷 1-8页

作者：张承慧李珂崔纳新邢国靖吴剑孙波山东大学控制科学与工程学院

面对能源和环境的巨大压力,混合动力汽车(hybrid electric vehicle,HEV)已成为汽车工业发展的重要方向。混合动力电动汽车与传统汽车有很大不同,具有独特而又复杂的能量及驱动系统,故对控制系统的要求更高和依赖性更强。该系统可以归结... 详细信息

面对能源和环境的巨大压力,混合动力汽车(hybrid electric vehicle,HEV)已成为汽车工业发展的重要方向。混合动力电动汽车与传统汽车有很大不同,具有独特而又复杂的能量及驱动系统,故对控制系统的要求更高和依赖性更强。该系统可以归结为一类具有高度不确定性和强非线性的混杂切换动态系统,其优化控制策略的优劣直接影响车辆的经济性、可靠性、安全性和舒适性。然而混合动力电动汽车能量及驱动系统的控制器设计却面临众多挑战,现代控制理论和技术则是解决这一技术瓶颈的关键手段。本文从系统与控制科学的角度,深刻全面地综述了HEV能量及驱动系统的能量管理策略、车载动力电池状态估计、驱动系统及其优化控制等关键科学与技术问题及其研究进展,最后指出了HEV能量及驱动系统优化控制技术和理论面临的挑战和发展趋势。

关键词：混合动力电动汽车能量及驱动系统能量管理策略电池状态估计

Balanced strength and ductility by asymmetric gradient nanostructure in AZ91 Mg alloy

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Journal of Materials Science & Technology 2024年第17期184卷 167-179页

作者： Bingqian Xu Jiapeng sun Lingling Wang jing Han Guosong wu College of Mechanics and Materials Hohai UniversityNanjing 211100China School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116China

High-strength Mg alloys have historically suffered from a challenge in achieving good ***,we report an asymmetric gradient nanostructure design prepared by ultrasonic severe surface rolling(USSR)at room *** conventional gradient-nanostructured materials that employ a hard-soft-hard sandwich structure,this new design incorporates a combined gradient distribution of grain microstructure and nanoprecipitates throughout the entire sample along the thickness *** nanoprecipitates are identified as theβ-Mg_(17)Al_(12)phase and are primarily generated through In-situ pre-cipitation promoted by the USSR-induced high-density dislocations and temperature ***-ing from this unique microstructure,an outstanding strength-ductility synergy is achieved,with a yield strength of 372.8 MPa,an ultimate tensile strength of 453.3 MPa,and an elongation of 11.5%.The en-hanced strength can be attributed to several mechanisms,including grain boundary strengthening,dislocation strengthening,precipitation strengthening,twin strengthening,and hetero-deformation induced(HDI)*** HDI hardening and activation of multiple deformation modes also contribute to good *** work provides a promising and effective method for overcoming the longstanding strength-ductility trade-offdilemma in Mg alloys.

关键词： Mg alloy Strength-ductility synergy Gradient nanostructure Precipitates AZ91

Linkage between water soluble organic matter and bacterial community in sediment from a shallow, eutrophic lake, Lake Chaohu, China

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Journal of Environmental Sciences 2020年第12期32卷 39-46页

作者： Changming Yang Jiliang sun Yingying Chen jing wu Yulai Wang Key Laboratory of Yangtze River Water Environment of the Ministry of Education Tongji UniversityShanghai 200092China Shanghai BaoSen Environmental Technology Co. Ltd.Shanghai 200439China School of Energy and Environment Anhui University of TechnologyMaanshan City 243002China

Lacustrine sediment played important roles in migration and transformation of its water soluble organic matter(WSOM), and the source and composition of WSOM would affect water trophic status and the fate of pollutants. However, we know little about the pathway of WSOM transformation and its driving bacterial communities in lacustrine sediment. In the present study, we investigated the spatial distribution patterns of sediment WSOM and its fluorescent fractions across Lake Chaohu using fluorescence spectroscopy, and explored WSOM compositional structure through our proposed calculated ratios. In addition, we also analyzed sediment bacterial community using Illumina sequencing technology, and probed the possible pathway of sediment WSOM transformation under the mediate of indigenous bacteria. Our results showed that the inflowing rivers affected the spatial distribution patterns of WSOM and its five fractions(including tyrosine-, tryptophan-, fulvic acid-, humic acid-like substances and soluble microbial productions), and sediment WSOM originated from fresh algae detritus or bacterial sources. In parallel, we also found that Proteobacteria(mainly γ-Proteobacteria and δ-Proteobacteria), Firmicutes(mainly Bacilli), Chloroflexi, Acidobacteria, Planctomycetes and Actinobacteria dominate sediment bacterial community. Furthermore, these dominant bacteria triggered sediment WSOM transformation, specifically, the humic acid-like substances could be converted into fulvic acid-like substances, and further degraded into aromatic protein-like and SMP substances. In addition, our proposed ratios(P-L:H-L, Ar-P:SMP and H-L ratio), as supplementary tool, were effective to reveal WSOM composition structure. These results figured out possible pathway of WSOM transformation, and revealed its microbial mechanism in lacustrine sediment.

关键词： Eutrophic lake DOM transformation Bacterial community EEMs-FRI Illumina sequencing

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多无人机协同规划研究综述

计算机工程与应用 2025年第1期61卷 42-58页

作者：宁聪范菁孙书魁云南民族大学电气信息工程学院昆明650500 云南民族大学云南省高校信息与通信安全灾备重点实验室昆明650500 云南民族大学云南省无人自主系统重点实验室昆明650500

无人机在各行各业中发挥重要作用,多无人机之间的合作已成为研究热点。针对任务分配与路径规划两个核心问题,整理和分析了多无人机协同规划两个关键问题之间的复杂性,以及子问题间的信息耦合因素,并重点探讨了解耦策略;从数学模型方面... 详细信息

无人机在各行各业中发挥重要作用,多无人机之间的合作已成为研究热点。针对任务分配与路径规划两个核心问题,整理和分析了多无人机协同规划两个关键问题之间的复杂性,以及子问题间的信息耦合因素,并重点探讨了解耦策略;从数学模型方面对多无人机协同规划问题的通用模型进行描述,整理归纳出常见环境建模方法和多目标优化求解的约束条件;综述了基于集中式控制和分布式控制的任务规划方法,以及启发式算法在多无人机协同规划中的应用和研究进展,并重点介绍了多无人机协同规划问题面临实时性要求下的协同规划方法;结合典型研究,讨论了多无人机协同规划问题的未来研究方法与挑战,展望多无人机协同规划的发展。

关键词：无人机解耦策略智能算法任务分配路径规划

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