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基于MaxEnt模型的细尤犀金龟在中国的适生分布区预测

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西南农业学报 2024年第7期37卷 1601-1610页

作者：张鸿辉舒旭余新林朱恩骄和秋菊赵敏易传辉西南林业大学林学院昆明650224 云南高黎贡山国家级自然保护区保山管护局腾冲分局云南腾冲679100 云南林业职业技术学院昆明650224 中国林业科学研究院高原林业研究所昆明650224 西南林业大学云南生物多样性研究院昆明650224

[目的]对濒危物种细尤犀金龟适生区进行预测,为其保护提供理论依据。[方法]基于地理分布记录和环境变量数据,采用MaxEnt模型,利用27个有效分布点和19个环境因子,借助ArcGIS软件模拟细尤犀金龟在中国当前气候条件和未来(2050s,2070s)RCP... 详细信息

[目的]对濒危物种细尤犀金龟适生区进行预测,为其保护提供理论依据。[方法]基于地理分布记录和环境变量数据,采用MaxEnt模型,利用27个有效分布点和19个环境因子,借助ArcGIS软件模拟细尤犀金龟在中国当前气候条件和未来(2050s,2070s)RCP2.6与RCP8.5此2种气候条件下的适生分布区,并筛选出影响分布的主导环境因子。[结果]对19个环境因子采用MaxEnt模型进行10次重复运算,计算出AUC值为0.986,表明MaxEnt模型精度高,同时去除掉贡献率和置换重要值较低的环境因子。采用MaxEnt模型中的“刀切法”筛选得到6个环境因子并进行分析,最终根据贡献率得出影响细尤犀金龟潜在地理分布的主导环境因子前4位依次为温度季节性(BIO4,53.7%)、最热季度的降水(BIO18,13.5%)、年降水量(BIO12,12.2%)和等温性(BIO3,11.8%)。在当前气候条件下,细尤犀金龟高适生区主要位于云南南部、西藏南部区域以及台湾地区中部零星区域。在2050年RCP2.6与2070年RCP8.5排放情景下,高适生区面积在台湾地区、云南和西藏部分地区虽有小幅度增加,但其它排放情景下的面积均有所减少。[结论]温度季节性、最热季度的降水、年降水量、等温性、最冷月份的最低温度和年温差是影响细尤犀金龟在中国潜在分布的主导环境因子。细尤犀金龟适生区的预测结果与其当前在中国的实际分布情况基本一致,但由于栖息地丧失、破碎化、退化以及生境的严重破坏,其未来的实际适生分布区存在进一步缩小和破碎化的趋势,濒危物种细尤犀金龟生存环境不容乐观。

关键词：细尤犀金龟潜在适生区濒危 MaxEnt ArcGIS

Six-Degree-of-Freedom Measurement of Plate Anchors in Centrifuge by Magnetometers

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China Ocean Engineering 2022年第6期36卷 871-879页

作者： shu shuang CheN chuan CheN Hao-ran LAI Ying Key Laboratory of the Ministry of Education for Geomechanics and Embankment Engineering College of Civil and Transportation EngineeringHohai UniversityNanjing 210098China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China

The six-degree-of-freedom movement of an offshore plate anchor is essential to evaluate anchor *** an emerging technology,magnetometer has shown its potential in measuring the six-degree-of-freedom movement of offshore anchors under 1-g model laboratory *** paper presents the feasibility of adopting a magnetometer system in geotechnical centrifuge *** factors that may affect the measuring accuracy of the magnetometer system are *** results demonstrate that the magnetometer system can accurately catch the anchor movement in the soils with the restrictions of:(1)the model anchor was made with stainless steel;(2)the system was placed at least 30 cm away from the side wall of soil model tank;(3)started the measurement when the artificial acceleration by centrifuge was stable.

关键词： magnetometer offshore plate anchors centrifuge testing trajectory orientation

Enhanced thermal- and impact-initiated reactions of PTFE/Al energetic materials through ultrasonic-assisted core-shell construction

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Defence Technology（防务技术） 2022年第8期18卷 1362-1368页

作者： Zhou-yang Wu Jin-xu Liu Song Zhang Xian-qing Liu Xiao Xu Wei-zhe Ma shu-kui Li chuan he School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Science and Technology on Transient Impact Laboratory No.208 Research Institute of China Ordnance Industries102202China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen518172China

A facile and economical approach was developed for the large-scale production of powdered core-shell structured PTFE/Al (CS-PA) energetic materials through ultrasonic-assisted mixing. The low-cost micrometer-sized PTFE and Al particles were used as starting materials. Under high-power ultrasonic waves, the PTFE powder was dispersed into nano-to sub-micrometer-sized particles and then encapsulated the Al microparticles to form the core-shell structure. The heat of combustion, burning rate, and pressurization rate of the powdered CS-PA were measured. The thermal-initiated reaction behavior was further evaluated using thermogravimetry-differential scanning calorimetry. Subsequently, the bulk CS-PA with a uniform microstructure was obtained via cold isostatic pressing of the powdered CS-PA followed by vacuum sintering. For the bulk CS-PA, the quasi-static compression behavior was characterized, and the impact-initiated reaction processes were conducted using the Split Hopkinson Pressure Bar (SHPB) and evaluated by a high-speed camera. Compared to physically mixed PTFE/Al materials, the powdered and bulk CS-PA demonstrated enhanced thermal- and impact-initiated reaction characteristics respectively, proving the effectiveness of our approach for constructing core-shell structures.

关键词： PTFE/Al Core-shell structure Energetic materials Ultrasonic-assisted mixing

Regulating silver nanowire size enables efficient photoelectric conversion

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Science China Chemistry 2020年第8期63卷 1046-1052页

作者： Jie Xu Kai Wang Yi Li Tao-Tao Zhuang Huai-Ling Gao Yang-Yi Liu chuan-Xin he shu-Hong Yu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China Department Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleCAS Center for Excellence in NanoscienceDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryUniversity of Science and Technology of ChinaHefei 230026China

The increasing demand for the state-of-the-art transparent conductive electrodes has received great interest in synthesizing silver nanowires(AgNWs)with a uniform diameter that exhibit excellent conductance,transparency,flexibility and mechanical ***,we report the controllable synthesis of ultrathin AgNWs with high aspect ratio via a polyol-assisted *** diameter of AgNWs can be continuously modulated from 20 to 80 nm by simply adjusting the aging *** selfassembled films fabricated by using AgNWs with a diameter of 20 nm as building blocks enable an excellent performance and show a sheet resistance of^30Ω/sq and an optical transmittance of 94%.In addition,such nanowire-based conductive films can keep the excellent flexibility and resistance after bending 10,000 ***,the intelligent dimming films prepared by this AgNW films also have excellent flexibility and stability.

关键词： silver nanowires polyol-assisted process assembly transparent conductive film conductive electrode

A novel large animal model of recurrent migraine established by repeated administration of inflammatory soup into the dura mater of the rhesus monkey

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Neural Regeneration Research 2019年第1期14卷 100-106页

作者： Ning Chen Wei Su shu-Hui Cui Jian Guo Jia-chuan Duan Hong-Xia Li Li he Department of Neurology West China Hospital Sichuan University Department of Science & Technology West China Hospital Sichuan University National Chengdu Center for Safety Evaluation of Traditional Chinese Medicine West China Hospital Sichuan University

Several animal models of migraine have been established, and those based on trigeminovascular system activation are widely accepted. How- ever, most of these models have been established on lower animals, such as rodents, and involve only a single administration of a noxious stimulus. In this study, an inflammatory soup （10 μL）, consisting of prostaglandin E2 （0.2 mM）, serotonin （2 mM）, bradykinin （2 raM） and histamine （2 raM）, was injected into the dura mater of conscious rhesus monkeys through an indwelling catheter. The infusion started on day 8 and was repeated every 3 days, for a total of six administrations, to induce neurogenic inflammation. We performed behavioral assessments and measured the expression of the oncogene c-fos, neuronal nitric oxide synthase （nNOS） and calcitonin gene related peptide （CGRP） ill the trigeminal system and in multiple brain regions involved in pain processing by immunohistochemical staining. Compared with monkeys in the control group, three of the four animals in the inflammatory soup group displayed decreased motor behaviors, and two showed increased ipsilateral nose and mouth secretions during the stimulus period. Higher expression levels of c-fos, nNOS and CGRP were found in various brain areas of experimental animals compared with controls, including the trigeminal nucleus caudalis, thalamus, hypothalamus, midbrain, pons and other areas involved in pain perception. These results suggest that repeated inflammatory soup stimulation of the dura activates the trigeminovascular system and produces migraine-like pathological changes and abnormal behaviors in conscious rhesus monkeys.

关键词： nerve regeneration migraine rhesus monkey neurogenic inflammation cellular oncogene fos neuronal nitric oxide synthase calcitonin gene related peptide trigeminal system behavior immunohistochemistry neural regeneration

基于蛋白组学探讨麦冬皂苷D改善肺纤维化的作用机制

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中国新药杂志 2024年第4期33卷 372-382页

作者：陈婷包晟川李京涛魏海梁惠毅闫曙光陕西中医药大学基础医学院胃肠病教研室咸阳712046 陕西省胃肠病证方药重点研究室咸阳712046 陕西中医药大学附属医院肝病一科咸阳712046 陕西中医药大学附属医院普外一科咸阳712046

目的:运用蛋白组学的方法研究麦冬皂苷D对小鼠肺纤维化的影响及其机制。方法:将C56BL/6小鼠按体质量随机分为正常组、模型组、阳性对照组和麦冬皂苷D组。除正常组外,其余各组小鼠气管滴注盐酸博来霉素5 mg·kg^(-1),24 h后阳性对照组给... 详细信息

目的:运用蛋白组学的方法研究麦冬皂苷D对小鼠肺纤维化的影响及其机制。方法:将C56BL/6小鼠按体质量随机分为正常组、模型组、阳性对照组和麦冬皂苷D组。除正常组外,其余各组小鼠气管滴注盐酸博来霉素5 mg·kg^(-1),24 h后阳性对照组给予强的松(5 mg·kg^(-1))灌胃,麦冬皂苷D组给予麦冬皂苷D(10 mg·kg^(-1))灌胃,连续给药14 d。通过显微CT观察肺组织影像学改变,染色观察小鼠肺纤维化程度,运用DIA定量蛋白组学技术检测肺组织中的差异蛋白,并分析这些差异蛋白富集的主要通路。运用Western blot(WB)对肺组织中的炎症相关蛋白进行验证。结果:与模型组比较,麦冬皂苷D给药后可显著改善小鼠肺纤维化的病理状态,CT表明小鼠肺实变减轻,染色提示肺胶原纤维化减少,肺组织中α-平滑肌肌动蛋白(α-SMA)阳性表达减轻。蛋白组学发现,相对于模型组,麦冬皂苷D组肺组织共有65个差异蛋白,其中上调蛋白46个、下调蛋白19个。GO功能富集发现,麦冬皂苷D调控的差异蛋白参与了生物过程、分子功能和细胞组分,主要富集于对压力的反应(response to stress)、碳水化合物衍生物结合(carbohydrate derivative binding)和肌原纤维(myofibril)。KEGG分析显示,麦冬皂苷D所涉及的信号通路主要包括冠状病毒疾病-新型冠状病毒肺炎(coronavirus disease-COVID-19)、补体和凝血级联(complement and coagulation cascades)、NOD样受体信号通路(NOD-like receptor signaling pathway)、肿瘤坏死因子信号通路(TNF signaling pathway)和白介素-17信号通路(IL-17 signaling pathway)等,WB结果证实麦冬皂苷D可显著降低炎症相关蛋白NOD样受体蛋白3(NLRP3)和IL-18,TNF-α,IL-6的表达(P<0.01,P<0.001)。结论:麦冬皂苷D可改善博来霉素所致的肺纤维化,其作用机制可能与减轻炎症反应、调节相关通路密切相关。

关键词：肺纤维化麦冬皂苷D 蛋白组学

A Facile Glycosylation of Spirostanol Catalyzed by Cadmium Carbonate

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Chinese Chemical Letters 2003年第3期14卷 229-232页

作者： chuan Chun ZOU shu Jie HOU 等 InstituteofMateriaMedica PekingUnionMedicalCollege&ChineseAcademyofMedicalSciencesBeijing100050 InstituteofMateriaMedica PekingUnionMedicalCollege&ChineseAcademyofMedicalSci

A facile glycosylation for the synthesis of spirostanol glycosides was reported. Using cadmium carbonate as a catalyst in CH3CN, a series of saponins was synthesized efficiently in a satisfactory yield.

关键词： Spirostanol glycosides glycosylation cadmium carbonate.

利托那韦片在中国健康受试者中的生物等效性研究

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中国临床药理学杂志 2024年第10期40卷 1502-1506页

作者：徐媛媛王传姝陈绍春丁佳翔王雪枫王何月谢晶周焕蚌埠医科大学药学院安徽蚌埠233000 蚌埠医科大学公共基础学院安徽蚌埠233000 蚌埠医科大学第一附属医院临床试验研究中心安徽埠233000 南京科利泰医药科技有限公司江苏南京210000

目的评估中国健康成年受试者在空腹及餐后条件下单次口服利托那韦片受试制剂和参比制剂的生物等效性。方法本研究按单中心、开放、随机、单剂量、两周期、两序列交叉设计,空腹组和餐后组均入组64例受试者。每周期口服受试制剂或参比制剂... 详细信息

目的评估中国健康成年受试者在空腹及餐后条件下单次口服利托那韦片受试制剂和参比制剂的生物等效性。方法本研究按单中心、开放、随机、单剂量、两周期、两序列交叉设计,空腹组和餐后组均入组64例受试者。每周期口服受试制剂或参比制剂,用高效液相色谱-质谱/质谱联用(HPLC-MS/MS)法测定血浆中利托那韦的药物浓度。用非房室模型,对其药代动力学参数进行评估,用SAS 9.4软件进行统计分析。结果空腹组利托那韦片受试制剂与参比制剂的主要药代动力学参数:Cmax分别为(791.90±400.20)和(809.60±449.14)ng·mL^(-1),AUC_(0-t)分别为(6072.61±2631.98)和(6296.30±3388.95)ng·h·mL^(-1),AUC_(0-∞)分别为(6129.59±2655.57)和(6347.26±3434.12)ng·h·mL^(-1)。餐后组利托那韦片受试制剂与参比制剂的主要药代动力学参数:Cmax分别为(512.37±233.60)和(521.74±223.87)ng·mL^(-1),AUC_(0-t)分别为(4203.43±2221.33)和(4200.13±1993.50)ng·h·mL^(-1),AUC_(0-∞)分别为(4259.21±2266.88)和(4259.63±2044.12)ng·h·mL^(-1)。空腹及餐后条件下受试者口服利托那韦片受试制剂和参比制剂100 mg后血浆中原型药物利托那韦的主要药代动力学参数Cmax、AUC_(0-t)及AUC_(0-∞)的几何均值比的90%置信区间均在80.00%~125.00%。结论利托那韦片受试制剂与参比制剂在空腹及餐后条件下在中国健康受试者体内具有生物等效性。

关键词：利托那韦片生物等效性药代动力学

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数控系统样条曲线插补技术研究综述

机械设计与制造 2024年第3期 353-356页

作者：盖荣丽马淑雅杜晓燕高守传大连大学信息工程学院辽宁大连116021

传统数控系统加工复杂曲线时,一般采用微小线段或圆弧段逼近的方法,加工精度低,易引发刀具抖动、机床振动等问题。随着CAD/CAM技术的发展,现代数控机床向高速度、高柔性方向发展,基于高质量加工的要求,提出样条曲线插补方法。对样条曲... 详细信息

传统数控系统加工复杂曲线时,一般采用微小线段或圆弧段逼近的方法,加工精度低,易引发刀具抖动、机床振动等问题。随着CAD/CAM技术的发展,现代数控机床向高速度、高柔性方向发展,基于高质量加工的要求,提出样条曲线插补方法。对样条曲线插补方法进行综述,首先阐述了插补技术的重要性;其次从进给速度、加工精度等角度系统分析了样条曲线插补方法,分别介绍了A样条插补、B样条插补和C样条插补;最后描述了三种插补方法的发展过程和最新研究动态,对其未来趋势做了总结和展望。

关键词：数控系统样条曲线插补 A样条插补 B样条插补 C样条插补高质量加工