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Physarum polycephalum-inspired adaptive optimization design of artificial microtubular networks

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Science China Chemistry 2025年

作者： Si-Min Zeng Di-Wei Zheng Ting Pan Xing-Lan Ding Yun Zhang Chi-Hui Yang Si-xue Cheng Xian-Zheng Zhang Key Laboratory of Biomedical Polymers of Ministry of Education&Department of Chemistry Wuhan University

Natural biological microtubular networks have undergone adaptive evolutionary selection and may offer viable solutions to design challenges in artificial microtubular networks. The plasmodium of the slime mold Physarum polycephalum(P. polycephalum) extends continuously to form a protoplasmic microtubular network structure, directly connecting food *** simulations revealed that the formation of this adaptive P. polycephalum microtubular network could be captured by a mathematical algorithm. Inspired by the P. polycephalum microtubular networks, we propose an adaptive optimization design method for artificial microtubular networks. Specifically, we utilized hydrogels with biodegradable and tissue-adhesive properties to replicate the P. polycephalum microtubular networks via photomask. In Rhodamine B diffusion and glucosecatalyzed reaction experiments, we found that the P. polycephalum microtubular networks exhibited significantly enhanced efficiency compared to vascular and artificial networks. Furthermore, we demonstrated the potential for uric acid(UA) degradation of the hydrogels with a real P. polycephalum microtubular network loaded with urate oxidase(UOx) in a rodent model of hyperuricemia. And this network achieved more than double the effect of the artificial network. This underscores the potential of natural microtubular networks to replace artificial microtubular networks.

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超声造影对肝脏局灶性病变的诊断价值

临床超声医学杂志 2013年第5期15卷 337-339页

作者：韦虹周显礼孙爱霞车德红薛伟力纪巧董雪迎哈尔滨医科大学第二临床医学院超声医学科哈尔滨市150086

目的观察肝脏局灶性病变的超声造影表现,评价超声造影在肝脏局灶性病变定性诊断中的价值。方法超声造影检查45例肝脏局灶性病变患者,采用编码相位反转技术和时间-强度曲线分析软件,分析肝脏局灶性病灶良恶性鉴别诊断的定量参数变化特征... 详细信息

目的观察肝脏局灶性病变的超声造影表现,评价超声造影在肝脏局灶性病变定性诊断中的价值。方法超声造影检查45例肝脏局灶性病变患者,采用编码相位反转技术和时间-强度曲线分析软件,分析肝脏局灶性病灶良恶性鉴别诊断的定量参数变化特征。结果超声造影肝脏恶性病灶始增时间和达峰时间均早于良性病灶及周围肝组织(P<0.05),增强时间短于良性病灶(P<0.01)。良恶性病灶和良性病灶的增强幅度差异无统计学意义,但均高于病灶周围肝组织(P<0.01)。结论应用时间-强度曲线取得的超声造影定量参数变化特征对肝局灶性病变的良恶性鉴别具有重要价值。

关键词：超声检查造影剂肝脏局灶性病变

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十四份雪茄烟种质资源鉴定评价

南方农业 2022年第7期16卷 64-69页

作者：康雨琪钟秋陈志华张华述彭菊陈娇娇周易学薛伟利四川农业大学四川成都611130 四川省德阳市烟草公司四川德阳618000 四川省烟草科学研究所四川成都610000

为筛选出优良的雪茄烟种质供国内雪茄烟育种和生产利用,有必要对引进雪茄烟种质资源的相关目标性状进行鉴定。对14份雪茄烟种质的植物学性状、生育期、抗病性、株型性状、叶片性状及病害发生情况进行鉴定评价。结果表明,14份雪茄烟种质... 详细信息

为筛选出优良的雪茄烟种质供国内雪茄烟育种和生产利用,有必要对引进雪茄烟种质资源的相关目标性状进行鉴定。对14份雪茄烟种质的植物学性状、生育期、抗病性、株型性状、叶片性状及病害发生情况进行鉴定评价。结果表明,14份雪茄烟种质的生育期适中,植物学性状、抗病性、株型性状和叶片性状存在较丰富的遗传变异;其中抗黑胫病的种质有3份,分别为印尼1号、德雪1号和德雪3号;除古巴5号和古巴8号的株型为橄榄形外,古巴6号的节距太短,其余种质的株型较为理想;筛选到具备茄衣潜势的种质2份,分别为德雪3号和古巴1号,其中德雪3号的叶片大小适中,叶型为宽椭圆形,叶片最薄,但支脉较多,生产上具有作为茄衣品种使用的可能性,须对其支脉数性状进一步改良;古巴1号的支脉最少,叶片较薄,也可以初步确定用作茄衣种质。

关键词：雪茄烟种质资源生育期株型性状叶片性状抗病性

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Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming Li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei Li xue-Yuan Liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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人工智能与政治安全形态演变:一项系统研究的尝试

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国际安全研究 2025年第1期43卷 54-72,156,157页

作者：封帅薛世锟上海国际问题研究院网络空间国际治理研究中心上海国际问题研究院上海200233

在人工智能时代,政治安全的内涵正在被不断深化和持续拓展,各国面临的政治安全风险也愈发复杂。根据系统科学理论,政治安全可以构建为一种政治安全系统,包含正反要素、四大结构面与动态稳定的功能。人工智能在经历从游离到输入的时序过... 详细信息

在人工智能时代,政治安全的内涵正在被不断深化和持续拓展,各国面临的政治安全风险也愈发复杂。根据系统科学理论,政治安全可以构建为一种政治安全系统,包含正反要素、四大结构面与动态稳定的功能。人工智能在经历从游离到输入的时序过程后,作为一种新的要素与政治安全系统发生互动。人工智能与政治安全的互动遵循“技术—应用—风险—系统”的逻辑过程,并实现对系统内其他要素的影响。这种影响全面且深刻,使得人工智能开始大面积嵌入政治安全系统,重构了政治安全结构。政治安全正在面临人工智能所带来的更复杂的风险形态,包括权力安全、制度安全与价值安全在内的政治安全内部生态都将发生深刻变化,推动整个政治安全形态经历深刻的变革。

关键词：人工智能政治安全国家安全系统科学

Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： Yi Jing Xin-Ran Liu Xing-Hua Wang Hui Han Sha-Sha Liang Xi-Meng Chen Dong-Hui Wei Lai-Sheng Wang xue-Nian Chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation

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食品科学 2025年第1期46卷 131-141页

作者： SUN Yupeng CHEN Ying SHANG Qingwen GUO Yanyin ZHANG Yuxiao WANG Yunqiao xue Qingyue College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049China Zichuan District Agricultural and Rural Affairs Service Center Zibo 255049China

To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before *** appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of *** results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli ***,during the growth stage,total sugar accumulation was higher in the 5-ARG *** addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest *** conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of ***,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.

关键词： arginine broccoli preharvest spraying nutrient accumulation storage quality postharvest senescence

基于强稳定收敛的偏正态联合位置与尺度模型的参数估计算法

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应用数学 2025年第1期38卷 201-210页

作者：薛潇吴刘仓昆明理工大学理学院云南昆明650500 昆明理工大学应用统计学研究中心云南昆明650500

传统的迭代算法(例如牛顿算法,EM算法等)在实际应用中,往往存在初始值较为敏感的问题.为解决这一问题,一种强稳定的收敛算法――Upper-crossing/Solution算法(以下称US算法)被提出,这种算法虽然在求解一元非线性函数时具有强稳定性,但... 详细信息

传统的迭代算法(例如牛顿算法,EM算法等)在实际应用中,往往存在初始值较为敏感的问题.为解决这一问题,一种强稳定的收敛算法――Upper-crossing/Solution算法(以下称US算法)被提出,这种算法虽然在求解一元非线性函数时具有强稳定性,但是不能推广到多元的情形.那么针对多元情形,本文将结合偏正态分布的随机表示,对偏正态联合位置与尺度模型的似然函数进行分层,并且利用MM算法得到一元的情形,再使用US算法构造强稳定的收敛算法.最后通过随机模拟分析和实例分析研究表明了US算法较牛顿迭代法大大降低了算法对初值的敏感度以及显著地提高了收敛的稳定性.

关键词：偏正态联合位置与尺度模型牛顿迭代法 US算法强稳定收敛

3D printing of cell-delivery scaffolds for tissue regeneration Jianmin xue and others

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Regenerative Biomaterials 2023年第1期10卷 839-852页

作者： Jianmin xue Chen Qin Chengtie Wu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Tissue engineering strategy that combine biomaterials with living cells has shown special advantages in tissue regeneration and promoted the development of regenerative *** particular,the rising of 3D printing technology further enriched the structural design and composition of tissue engineering scaffolds,which also provided convenience for cell loading and cell delivery of living *** this review,two types of cell-delivery scaffolds for tissue regeneration,including 3D printed scaffolds with subsequent cell-seeding and 3D cells bioprinted scaffolds,are mainly *** devote a major part to present and discuss the recent advances of two 3D printed cell-delivery scaffolds in regeneration of various tissues,involving bone,cartilage,skin tissues *** two types of 3D printed cell-delivery scaffolds have some shortcomings,they do have generally facilitated the exploration of tissue engineering scaffolds in multiple tissue *** is expected that 3D printed cell-delivery scaffolds will be further explored in function mechanism of seeding cells in vivo,precise mimicking of complex tissues and even organ reconstruction under the cooperation of multiple fields in future.

关键词： cell-delivery 3D printing tissue regeneration