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Commercial Efforts Flail to Replace Aging International Space Station
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作者 Chris Palmer 《Engineering》 2025年第5期6-8,共3页
Released in September 2024 by an oversight committee of the US National Aeronautics and Space Administration(NASA),a safety report about the International Space Station(ISS)cited,in addition to 50 other“areas of conc... Released in September 2024 by an oversight committee of the US National Aeronautics and Space Administration(NASA),a safety report about the International Space Station(ISS)cited,in addition to 50 other“areas of concern,”a troublesome leak first detected six years ago in one of the station’s modules[1].Given the persistent leak,called“a top safety risk”[2],and the fact that the space sta-tion has outlived its original life expectancy by more than 10 years,the agency’s current plans call for decommissioning the ISS in 2031 by dragging it into the Pacific Ocean[3]. 展开更多
关键词 Pacific Ocean international space station iss citedin safety report international space station space sta tion LEAK DECOMMISSIONING AGING
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伺服电机的抗扰动转动惯量辨识算法研究
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作者 谢芳 于飞 安超晨 《机械设计与制造》 北大核心 2026年第1期15-19,共5页
针对工况变化时伺服系统因负载扰动引起的伺服电机定位偏差问题,提出了一种基于转矩信号控制的梯度校正算法用于在线辨识转动惯量,以增加伺服系统转动惯量辨识的抗扰动能力。首先,建立永磁同步电机控制模型,推导出影响转动惯量辨识的参... 针对工况变化时伺服系统因负载扰动引起的伺服电机定位偏差问题,提出了一种基于转矩信号控制的梯度校正算法用于在线辨识转动惯量,以增加伺服系统转动惯量辨识的抗扰动能力。首先,建立永磁同步电机控制模型,推导出影响转动惯量辨识的参数。其次,针对传统梯度校正算法动态性能不足的问题,引入参数可调的抗扰动控制梯度校正算法,增加了算法的抗扰能力,实现变化工况下的转动惯量辨识。最后,搭建实验平台并验证该辨识算法的快速性、准确性和较强的抗扰能力。 展开更多
关键词 伺服电机 转动惯量辨识 抗扰动性能 梯度校正算法
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“5E”康复护理联合间歇导尿术在脊髓损伤神经源性膀胱患者中的应用
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作者 孔培培 翟清华 +2 位作者 张会 李树强 刘晓辉 《中国实用神经疾病杂志》 2026年第1期85-89,共5页
目的探讨“5E”康复护理联合间歇导尿术在脊髓损伤后神经源性膀胱患者中的应用效果。方法选取2022-03—2025-02郑州大学第二附属医院康复医学科2个病区收治的42例脊髓损伤后神经源性膀胱患者为研究对象,随机分为对照组和观察组,各21例... 目的探讨“5E”康复护理联合间歇导尿术在脊髓损伤后神经源性膀胱患者中的应用效果。方法选取2022-03—2025-02郑州大学第二附属医院康复医学科2个病区收治的42例脊髓损伤后神经源性膀胱患者为研究对象,随机分为对照组和观察组,各21例。对照组实施间歇导尿术和常规护理,观察组在间歇导尿术和常规护理基础上联合“5E”康复护理干预。干预4周后,比较2组最大膀胱安全容量、排尿期最大膀胱内压、残余尿量、尿道括约肌功能、汉密尔顿焦虑量表(HAMA)评分及世界卫生组织生活质量简表(WHOQOL-BREF)评分,记录并发症发生情况。结果干预后,观察组与对照组最大膀胱安全容量、排尿期最大膀胱内压、残余尿量比较,差异均有统计学意义(P<0.05)。干预后,观察组与对照组尿道括约肌松弛患者及尿道括约肌痉挛或失协调患者排尿期最大尿道压力比较,差异均有统计学意义(P<0.05)。干预后,观察组与对照组HAMA评分、WHOQOL-BREF评分比较,差异均有统计学意义(P<0.05)。结论“5E”康复护理协同间歇导尿术管理神经源性膀胱,可改善脊髓损伤患者的排尿功能及尿道括约肌功能,改善负面情绪和生活质量。 展开更多
关键词 脊髓损伤 神经源性膀胱 “5E”康复护理 间歇导尿术 排尿功能 负面情绪 尿路感染
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FOCUS 夫妻干预对不孕症患者夫妇心理状况及生育生活质量的影响
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作者 吴姗 马瑞条 杜苓燕 《临床心身疾病杂志》 2026年第1期60-64,共5页
目的探讨FOCUS夫妻干预对不孕症患者夫妇心理状况及生育生活质量的影响。方法将96对不孕症患者及其配偶作为研究对象,随机分成研究组和对照组,各48对。对照组受试者给予常规干预措施,研究组受试者在对照组基础上给予FOCUS夫妻干预。干... 目的探讨FOCUS夫妻干预对不孕症患者夫妇心理状况及生育生活质量的影响。方法将96对不孕症患者及其配偶作为研究对象,随机分成研究组和对照组,各48对。对照组受试者给予常规干预措施,研究组受试者在对照组基础上给予FOCUS夫妻干预。干预前后,比较两组受试者心理弹性[心理弹性量表(CD-RISC)评分]、生育压力[生育压力量表(FPI)评分]、总体幸福感[总体幸福感量表(GWBS)评分]、夫妻支持应对水平[夫妻支持应对量表(DCI)评分]及生育生活质量[生育生活质量问卷评分]。结果干预后,两组患者及其配偶CD-RISC、GWBS、DCI评分较干预前升高,且研究组高于对照组(P<0.05或0.01);两组患者及其配偶FPI评分较干预前降低,且研究组低于对照组(P<0.01);两组受试者生育生活质量总优良率较干预前提高,且研究组高于对照组(P<0.05或0.01)。结论FOCUS夫妻干预应用于不孕症患者夫妇临床效果良好,可改善夫妻双方的心理状况和生育生活质量。 展开更多
关键词 不孕症 FOCUS夫妻干预 心理状况 生育生活质量
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高等教育新质生产力的理论阐释与发展本质
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作者 齐慧姝 尹小诗 《科教文汇》 2026年第1期1-5,共5页
发展新质生产力是推动高等教育高质量发展的内在要求与重要路径。本文以马克思生产力理论为基础,对“教育生产力”和“高等教育生产力”的内涵进行理论溯源与系统阐释,进而明确了“高等教育新质生产力”的理论内涵。高等教育新质生产力... 发展新质生产力是推动高等教育高质量发展的内在要求与重要路径。本文以马克思生产力理论为基础,对“教育生产力”和“高等教育生产力”的内涵进行理论溯源与系统阐释,进而明确了“高等教育新质生产力”的理论内涵。高等教育新质生产力是由新质教育劳动者、新知教育劳动对象和新智教育劳动资料构成的有机整体,其核心特征在于高科技赋能、创新驱动以及与高质量发展目标的深度契合。高等教育新质生产力的本质要求在于推动教育高质量发展,具体体现为巩固和提升教学质量、深化教师队伍建设以及优化学科专业设置,从而为高等教育服务国家战略与社会需求提供理论支撑。 展开更多
关键词 高等教育 马克思生产力理论 新质生产力 理论阐释
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Fixation and Creep of Compressed Wood of Chinese Fir Irradiated with Gamma Rays 被引量:1
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作者 王洁瑛 赵广杰 《Forestry Studies in China》 CAS 2001年第1期58-65,共8页
In order to discuss the mechanisms of permanent fixation of wood compression set , compressed wood of Chinese fir (Cunninghamia lanceolata) was irradiated by gamma rays from 60 Co. The irradiation doses wer... In order to discuss the mechanisms of permanent fixation of wood compression set , compressed wood of Chinese fir (Cunninghamia lanceolata) was irradiated by gamma rays from 60 Co. The irradiation doses were 0 (for match specim ens), 10 3, 5×10 3, 10 4, 5×10 4, 10 5, 5×10 5, 10 6, 5×10 6 Gy, res pectively. Then the weight loss, the equilibrium moisture content (EMC), the rec overy of wood compression set after adsorption (RSA) and the recovery after imme rsion in water (RSW), as well as the creep behaviour under a dry specimen condit ion and under an adsorption and subsequent desorption condition were measured an d discussed. This research proves that the doses of gamma irradiation have great effect on weight loss, EMC, RSA, RSW of irradiated compressed wood of Chinese f ir. The weight loss and the EMC increase, the RSA and the RSW fall drastically w hen the irradiation doses exceed 10 6 Gy. Both the instantaneous compliance and the creep compliance of the irradiated specimens under the two measurement cond itions show the general trend of increase with the increase of gamma irradiation doses. It can be deduced that decomposition or decrystallization reactions happ en in the wood cell wall at high gamma irradiation doses, especially at doses of around 5×10 6 Gy. In addition, this research proves that decomposition of mai n components of cell wall of compressed wood will lead to fixation of compressio n set of wood to a certain degree. 展开更多
关键词 gamma irradiation compressed wood Chinese fir fixa tion CREEP
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Determination of Heavy Metals in Dendrobium candidium Wall.ex Lindl.by ICP-MS 被引量:3
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作者 郑龙 杨春亮 +1 位作者 苏子鹏 叶剑芝 《Agricultural Science & Technology》 CAS 2015年第12期2592-2595,共4页
[Objective] This research aimed to establish an inductively coupled plasma mass spectrometry (ICP-MS) method for determination of five kinds of heavy metals (Pb, Cd, Cu, As and Hg) in Dendrobium candidium Wall. ex... [Objective] This research aimed to establish an inductively coupled plasma mass spectrometry (ICP-MS) method for determination of five kinds of heavy metals (Pb, Cd, Cu, As and Hg) in Dendrobium candidium Wall. ex Lindl. [Method] The samples were digested in HNO3-H202 acids system by closed vessel microwave di- gestion. At the same time, internal standard was added to avoid the matrix effect. [Result] The five kinds of heavy meals all showed good linear relationships, and the correlation coefficients ranged from 0.998 2 to 0.999 9. The detection limits of the five kinds of heavy metals were in the range of 0.008-0.750 μg/L, while the stan- dard recovery rates were in the range of 90.4%-96.9%. The relative standard devi- ations ranged from 1.6% to 8.2%. The heavy metals in the Ginseng and Astragalus national standard samples were determined by the established ICP-MS method, and the results were in conformity with the standard values. [Conclusion] The established method has simple and convenient operation and accurate and reliable results, and it meets the requirements by determination of heavy metals in Dendrobium candididium Wall. ex Lindl. 展开更多
关键词 Dendrobium candidium Wall. ex Lindl. Heavy metals Microwave diges- tion ICP-MS
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Standard Operating Procedure of Houttuynia cordata Thunb.Plastic Greenhouse Cultivation 被引量:1
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作者 钟军 戴林建 《Agricultural Science & Technology》 CAS 2016年第7期1571-1576,共6页
This standard operating procedure stipulated the natural condition of pro- ducing area, cultivation technique, disease and pest control, harvest, quality stan- dard, packaging, transportation and storage of H. cordata... This standard operating procedure stipulated the natural condition of pro- ducing area, cultivation technique, disease and pest control, harvest, quality stan- dard, packaging, transportation and storage of H. cordata, in order to provide a ba- sis for the standard cultivation of H. cordata. 展开更多
关键词 Houttuynia cordata l'hunb Plastic Greenhouse Standardization produc- tion Standard Operating Procedure
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Identification and Cu Enrichment Capacity of TLSB_2-K, a Cu-tolerant Strain 被引量:1
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作者 康薇 郑进 《Agricultural Science & Technology》 CAS 2014年第12期2081-2084,2144,共5页
[Objective] The Cu-tolerance and Cu enrichment capacity of TLSB2-K were investigated. [Method] The previously isolated TLSB2-K strain was identified though morphological observation, gram staining and 16S rDNA sequenc... [Objective] The Cu-tolerance and Cu enrichment capacity of TLSB2-K were investigated. [Method] The previously isolated TLSB2-K strain was identified though morphological observation, gram staining and 16S rDNA sequence alignment. In ad- dition, the effects of temperature, pH and osmotic pressure on the growth of strain were also investigated by using shaking culture. The Cu-tolerance and Cu enrich- ment capacity of TLSB2-K strain under Cu stress were also studied. [Result] The results showed TLSB2-K belongs to Bacillus spp., and its optimum growth conditions were as follows: temperature, 27 ~C; pH, 7.0; osmotic pressure, 1.1% NaCI. When the Cu concentration ranged from 100 mg/L to 500 mg/L, the strain grew well; when the Cu concentration ranged from 100 mg/L to 400 mg/L, the Cu content in bacteria was increased with the increase of Cu concentration; when the Cu con- centration was 400 mg/L and the incubation time was 30 h, the Cu content in bac- teria reached the peak (2 250 mg/kg); the highest tolerant concentration was 700 mg/L. [Conclusion] TLSB2-K strain had relatively high Cu tolerance and Cu enrich- ment capacity. They had important theoretical research and engineering application values. 展开更多
关键词 Soil contamination Cu tolerance Bacillus cereus Molecular identifica- tion Enrichment capacity
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Research Progress and Identification Method of Apple Stress Resistance
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作者 王贵平 王金政 +2 位作者 薛晓敏 路超 聂佩显 《Agricultural Science & Technology》 CAS 2013年第10期1413-1416,共4页
In the research, changes of apple chemistry, and molecule, under stresses, are n terms of morphology, physiology, bio- illustrated and research and identifica- tion methods of apple resistance are explored involving ... In the research, changes of apple chemistry, and molecule, under stresses, are n terms of morphology, physiology, bio- illustrated and research and identifica- tion methods of apple resistance are explored involving drought-resistance, flood-re- sistance, salt-stress resistance, cold-hardiness and heat-resistance. In addition prospects of apple resistance research are proposed, as well. 展开更多
关键词 APPLE Adverse stress Stress resistance Research progress Identifica- tion method
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GeoStation地质外业系统研究与应用 被引量:11
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作者 唐海涛 王国光 卓胜豪 《人民长江》 北大核心 2017年第15期46-49,共4页
针对目前地质勘察人员野外数据处理广泛采用的"铅笔+记录纸"的作业方式,开发了一种基于移动终端的地质外业系统,旨在帮助地质勘察人员实现地质外业数据采集的信息化。通过将已整理入库的数据离线存储至移动终端并携带到勘察现... 针对目前地质勘察人员野外数据处理广泛采用的"铅笔+记录纸"的作业方式,开发了一种基于移动终端的地质外业系统,旨在帮助地质勘察人员实现地质外业数据采集的信息化。通过将已整理入库的数据离线存储至移动终端并携带到勘察现场,实现查阅和及时更新;并在数据采集完成后在线上传至服务器。该研究改变了传统野外数据记录中"铅笔+记录纸"的作业方式,对于实现地质勘察工作电子化,减少重复工作量,提高数据采集、整理效率具有重要的意义。工程应用结果表明,该系统大大提高了地质勘察工作效率,具有广阔的应用前景。 展开更多
关键词 地质外业系统 移动终端 地质信息化
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Study on Growth and Development and Dry Matter Production of Greenhouse Tomato in North China
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作者 王停停 温祥珍 +2 位作者 张玲 袁婷婷 李亚灵 《Agricultural Science & Technology》 CAS 2016年第7期1638-1641,1713,共5页
[Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar 'Jinguo No.l' as the experimental ma... [Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar 'Jinguo No.l' as the experimental material, the ex- periments were conducted in a solar greenhouse located in Taigu, Shanxi (37o25' N, 112o25' E) from March to July, in 2014 and 2015. [Result] The plant height, leaf number, leaf area and dry matter production of greenhouse tomato increased lin- early with the increased days after transplantation, and their growth rates were 2.74 cm/d, 0.32 leaf/d, 70 cm2/d and 9.4 g/(m2.d), respectively. The fruit dry weight also showed a linear relationship with the plant dry weight. After fruit setting, the fruit dry weight was increased by about 0.69 g when the plant dry weight was increased by 1 g. The allocation proportions of dry matter in tomato roots, stems and leaves de- clined significantly from plant flowering to fruiting, while the proportion of fruit dry weight in plant dry weight increased significantly, exceeding 60%. There was a strong linear relationship between dry matter production of tomato and effective cu- mulative temperature (sum of temperature higher than 10 ^(3) in the solar green- house, and the dry matter production was increased by about 0.73 g/m2 when the effective cumulative temperature was increased by one unit. The dry matter produc- tion of tomato plant also showed a strong linear relationship with photosynthetic ac- tive radiation (PAR) in the greenhouse, and about 3.4 g of dry matter was synthe- sized per unit (M J) of PAR. [Conclusion] Extending the growing period and improv- ing the temperature and light conditions could increase the dry matter production of tomato. 展开更多
关键词 Solar greenhouse TOMATO Growth and development Dry matter alloca- tion
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Comparions of Required Nitrogen Fertilizers by Hybrid Cultivar and Conventional Cultivar of Rapeseed(Brassica napus L.)
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作者 李银水 余常兵 +4 位作者 谢立华 胡小加 秦璐 廖祥生 廖星 《Agricultural Science & Technology》 CAS 2015年第10期2231-2237,共7页
[Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional ... [Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional cultivar ZS10, were compared through two field experiments. In Experiment 1, seed yield and optimum N application rate were assessed in the field with five N application treatments. In Expedment 2, N was applied uniformly at 180 kg/hm2, and plant biomass and N accumulation were measured at several developmental stages, while N use efficien- cy was calculated for rape at maturity. [Results] The experiment 1 results showed that seed yields of ZY5628 and ZY7819 were both significantly higher than that of ZS10, and compared to ZS10, optimum yield (plateau yield) was higher by 18.7% and 20.2%, while the recommended N application rate was lower by 9.5% and 9.6% for ZY5628 and ZY7819, respectively. The experiment 2 results showed that during vegetative development, all three cultivars exhibited similar accumulations of plant biomass and N, but through flowering and maturity ZY5628 and ZY7819 pro- duced more biomass, acquired more N, and utilized acquired N more efficiently to- wards seed production than ZS10. [Conclusion] With equivalent inputs, the hybrid rapeseed cultivars ZY5628 and ZY7819 tested herein yield more seed with higher N use efficiency than the conventional rapeseed ZS10. This information will be valu- able for growers seeking to improve efficiency while reducing costs of rape production in China. 展开更多
关键词 Rapeseed (Brassica napus. L) Hybrid cultivars Yield Nitrogen applica- tion rate Nitrogen use efficiency
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Effect of Cultivation Conditionss on Quality Parameters of High Grade Hybrid Rape of Brassica napus L.
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作者 赵继献 任廷波 程国平 《Agricultural Science & Technology》 CAS 2013年第1期59-68,共10页
[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapesee... [Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapeseed. [Method] By using Youyan 599 and Sanbei 98 as experimental materials, quadratic orthogonal rotation combination with five factors was designed for this study. [Result] Erucic acid content was nega- tively correlated with sowing date and nitrogen fertilizer, positively correlated with plant density. Glucosinolate content was negatively correlated with sowing date, positively correlated with potash fertilizer amount. Oil content was negatively correlated with sowing date and nitrogen fertilizer amount, positively correlated with plant density and potash fertilizer amount. Protein content was positively correlated with sowing date and nitrogen fertilizer amount, negatively correlated with plant density and potash fer- tilizer amount. Oleic acid content was negatively correlated with phosphate fertilizer amount, positively correlated with nitrogen fertilizer amount. Palmitic acid was nega- tively correlated with potash fertilizer amount, positively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Youyan 599, but negatively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Sanbei 98. Stearic acid content was posi- tively correlated with sowing date, plant density, nitrogen fertilizer amount and phos- phate fertilizer amount. Linoleic acid was positively correlated with density and nitroge- nous fertilizer, but negatively correlated with potash fertilizer amount. Linolenic acid was positively correlated with nitrogen fertilizer amount and potash fertilizer amount. Eicosenoic acid was negatively correlated with sowing date. There were positive cor- relations and negative correlations among cultivation conditions and quality parame- ters, and the positive correlations and negative correlations could counteract each other. Expression of quality parameters for each treatment was the combined effect. Among the 50 pairs of simple correlations of five cultivation factors and ten quality parameters, 26 pairs were consistent between two varieties, 24 pairs of simple corre- lation were not. Sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount showed significant influence on erucic acid of two varieties, but small effect on palmitic acid. [Conclusion] The combined effect of the five cultivation factors could not fundamentally improve the quality traits of high grade hybrid rapeseed. 展开更多
关键词 Hybrid rapeseed Cultivation factor Quality parameters Orthogonal rota- tion combination design EFFECT
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火麻仁蛋白包埋蓝靛果高聚原花青素的工艺优化及复合颗粒体外消化与抗氧化活性
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作者 朱玲 王崑仑 +8 位作者 张馨笛 韩亚希 陈晴 沙迪昕 樊晶 周野 姚鑫淼 李波 管立军 《食品研究与开发》 2026年第1期1-12,共12页
为提高蓝靛果原花青素的稳定性,该研究以火麻仁蛋白为壁材,采用反溶剂法包埋蓝靛果高聚原花青素,以包封率为响应值,采用Box-Behnken响应面试验设计对包埋工艺进行优化,确定最佳的包埋条件。首先采用碱提酸沉法提取火麻仁蛋白,并测定其... 为提高蓝靛果原花青素的稳定性,该研究以火麻仁蛋白为壁材,采用反溶剂法包埋蓝靛果高聚原花青素,以包封率为响应值,采用Box-Behnken响应面试验设计对包埋工艺进行优化,确定最佳的包埋条件。首先采用碱提酸沉法提取火麻仁蛋白,并测定其溶解度[(99.97±2.01)%,pH12],从蓝靛果中提取原花青素并测定其纯度[(9.81±0.38)%]和平均聚合度(5.06±0.22)。最佳的包埋条件为蓝靛果高聚原花青素浓度2.8 mg/mL、火麻仁蛋白溶液与蓝靛果高聚原花青素溶液体积比4.5∶1、滴加速度2.5 mL/min、转速1 100 r/min。在此最佳条件下,包封率为(82.98±1.32)%。对制备的复合颗粒的体外释放行为和体外消化过程中的稳定性进行探究,并测定复合颗粒的体外抗氧化活性。研究表明,复合颗粒对蓝靛果高聚原花青素的体外释放和体外消化分别具有缓释作用和保护作用;复合颗粒在DPPH和ABTS+自由基清除试验中均表现出良好的抗氧化能力,半抑制浓度(half maximal inhibitory concentration,IC50)值分别为6.10 mg/mL和0.88 mg/mL。 展开更多
关键词 火麻仁蛋白 蓝靛果高聚原花青素 工艺优化 体外消化 抗氧化活性
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变转速工况下双圆弧弧齿锥齿轮裂缝检测方法
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作者 周晓萍 王宁 +1 位作者 赵桂清 赵岭 《机械设计与制造》 北大核心 2026年第1期250-254,260,共6页
在变转速工况下,双圆弧弧齿锥的啮合刚度在啮合过程中会出现非线性波动,激励齿轮副的振动,产生丰富的啮合频率成分。而裂缝频率的幅值通常较低,容易被产生的大量啮合频率掩盖,较难获取与之相映射的故障类型,影响齿轮裂缝检测的准确性。... 在变转速工况下,双圆弧弧齿锥的啮合刚度在啮合过程中会出现非线性波动,激励齿轮副的振动,产生丰富的啮合频率成分。而裂缝频率的幅值通常较低,容易被产生的大量啮合频率掩盖,较难获取与之相映射的故障类型,影响齿轮裂缝检测的准确性。因此,提出变转速工况下双圆弧弧齿锥齿轮裂缝检测方法。采用多速率滤波器组分解双圆弧弧齿锥齿轮振动信号,通过分裂的增广拉格朗日收缩原理提取信号低频共振分量,并利用最小熵解卷积技术提升低频分量中被噪声淹没的故障冲击成分,结合峭度谱方法从复杂的振动信号中提取出与裂缝故障最为紧密相关的特征频带。对特征频带进行包络分析及快速傅里叶变换,突出啮合频率掩盖下的设备故障特征信号,从而识别出与齿轮裂缝故障相关的特征频率。由此,将特征频率作为输入,采用RBF神经网络建立裂缝特征与故障类型之间的映射关系,实现齿轮裂缝的精准检测。实验结果表明,所提方法通过利用最小熵解卷积技术和峭度谱方法可以有效提取信号裂缝故障频率特征,并充分利用特征频率信息,使得齿轮裂缝检测结果与实际结果一致。说明利用该方法可以有效检测双圆弧弧齿锥齿轮裂缝检测。 展开更多
关键词 变转速工况 双圆弧弧齿锥齿轮 RFB网络 裂缝检测方法 裂缝故障频率特征
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共病负担与老年非ST段抬高急性冠脉综合征患者心脑血管不良事件的相关性
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作者 施景文 汤雯 +6 位作者 邢云利 王珊 卢尚欣 侯晓沛 刘冰 胡洁琼 孙颖 《中华老年多器官疾病杂志》 2026年第1期50-54,共5页
目的探究年龄校正的查尔森共病指数(aCCI)与老年非ST段抬高急性冠脉综合征(NSTE-ACS)患者院外1年发生心脑血管不良事件(MACCE)的相关性。方法本研究为回顾性队列研究。收集2020年1月至2021年11月首都医科大学附属北京友谊医院心脏中心... 目的探究年龄校正的查尔森共病指数(aCCI)与老年非ST段抬高急性冠脉综合征(NSTE-ACS)患者院外1年发生心脑血管不良事件(MACCE)的相关性。方法本研究为回顾性队列研究。收集2020年1月至2021年11月首都医科大学附属北京友谊医院心脏中心、老年医学科住院患者528例。根据aCCI将研究对象分为低aCCI组和高aCCI组,采用Kaplan-Meier法计算不同aCCI患者MACCE发生率,采用多因素Cox回归分析不同aCCI组与老年NSTE-ACS患者院外1年发生MACCE相关性。采用SPSS 27.0软件进行数据分析。根据数据类型,组间比较分别采用t检验、非参数检验及χ^(2)检验。结果研究对象中位年龄72(68,76)岁,男性308例(58.3%)。高aCCI组患者251例,低aCCI组患者277例。高aCCI组患者年龄更大,心肌损伤标志物水平更高,容易合并衰弱、多重用药及日常生活能力减低(P<0.05)。随访1年发现,高aCCI组患者新发MACCE风险明显升高(log-rank P=0.0002)。调整多种混杂因素,当aCCI为连续变量时,aCCI每增加1个单位时,新发MACCE风险将增加21.3%(HR=1.21395%CI 1.043~1.412;P=0.012);当aCCI为分类变量,高aCCI组新发MACCE风险将增加85.8%(HR=1.85895%CI 1.119~3.083;P=0.017)。结论对于老年NSTE-ACS患者,较高的aCCI与较高的1年MACCE发生风险相关,早期对老年NSTE-ACS进行aCCI评估,改善不良预后。 展开更多
关键词 老年人 年龄校正的查尔森共病指数 非ST段抬高急性冠脉综合征 风险分层 预后
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HIV阳性女性宫颈高危HPV感染与宫颈病变的关联分析
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作者 汤恋花 陈琳 +1 位作者 高玉环 龙滨 《中国计划生育学杂志》 2026年第1期209-214,共6页
目的:考察人类免疫缺陷病毒(HIV)阳性女性宫颈高危人乳头瘤病毒(hrHPV)感染与宫颈病变的关联。方法:收集2018年1月—2025年3月于本院感染妇科门诊就诊的HIV阳性女性167例纳入HIV组,行宫颈癌筛查的非HIV女性120例纳入对照组。将HIV组中... 目的:考察人类免疫缺陷病毒(HIV)阳性女性宫颈高危人乳头瘤病毒(hrHPV)感染与宫颈病变的关联。方法:收集2018年1月—2025年3月于本院感染妇科门诊就诊的HIV阳性女性167例纳入HIV组,行宫颈癌筛查的非HIV女性120例纳入对照组。将HIV组中按是否合并hrHPV分为hrHPV组和非hrHPV组。纳入对象均接受了HPV筛查、液基细胞学(LBC),必要时行阴道镜下活检、HIV载量及CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)检测。结果:HIV组HPV感染、多重HPV感染、细胞学结果异常、其他阴道疾病感染、宫颈病变等均高于对照组(P<0.05)。HIV组HPV感染率70.1%,其中hrHPV感染率54.5%(91例),hrHPV分型比例较高的前4位分别为HPV16、HPV52、HPV58、HPV18,单一感染61.5%、双重感染28.6%、三重感染7.7%、四重感染2.2%。hrHPV组(n=91)和非hrHPV组(n=26),hrHPV组双重、三重或多重HPV感染、细胞学结果异常、其他阴道疾病感染,以及慢性宫颈炎、总宫颈病变均高于非hrHPV组(均P<0.05),宫颈上皮内瘤变(CIN)、宫颈癌、LSIL、HSIL与是否感染hrHPV未见关联(P>0.05)。结论:HIV感染增加女性感染hrHPV风险,hrHPV感染可显著增加细胞学异常及其他阴道感染风险,检出的主要hrHPV型别为HPV16、52、58和18。感染hrHPV的HIV阳性女性其慢性宫颈炎和总宫颈病变的发生率较高,hrHPV可能有助于驱动宫颈病变的发生发展。 展开更多
关键词 女性 人类免疫缺陷病毒 高危人乳头瘤病毒 感染 宫颈病变
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Research on the effect estimation of seismic safety evaluation
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作者 邹其嘉 陶裕禄 《地震学报》 CSCD 北大核心 2004年第1期84-93,共10页
Seismic safety evaluation is a basic work for determining the seismic resistance requirements of major construc-tion projects. The effect, especially the economic effect of the seismic safety evaluation has been gener... Seismic safety evaluation is a basic work for determining the seismic resistance requirements of major construc-tion projects. The effect, especially the economic effect of the seismic safety evaluation has been generally con-cerned. The paper gives a model for estimating the effect of seismic safety evaluation and calculates roughly the economic effect of seismic safety evaluation with some examples. 展开更多
关键词 地震安全性评价 经济效益 社会效益 评估模型
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富血小板血浆治疗神经根性腰痛症的研究进展及前景
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作者 史瑞 陈国栋 +2 位作者 王鑫 陈耀龙 徐国银 《颈腰痛杂志》 2026年第1期8-12,共5页
神经根性腰痛(LRP)是由于神经受压后损伤导致的腰部疼痛症状。富血小板血浆(PRP)是一种新兴的自体生物制剂,在LRP治疗中具有潜在应用价值。多项临床研究表明,PRP可作为类固醇的有效替代方案,尤其具有更突出的远期疗效。其作用机制主要... 神经根性腰痛(LRP)是由于神经受压后损伤导致的腰部疼痛症状。富血小板血浆(PRP)是一种新兴的自体生物制剂,在LRP治疗中具有潜在应用价值。多项临床研究表明,PRP可作为类固醇的有效替代方案,尤其具有更突出的远期疗效。其作用机制主要在于调节炎症微环境、释放大量生长因子和细胞因子,发挥抗凋亡、抗纤维化和神经保护作用,从而促进神经修复再生和功能恢复,缓解神经压迫症状。与传统药物相比,PRP的安全性更高。然而,PRP临床应用仍存在起效较慢,对急性疼痛效果有限及制备标准化不足等局限性。未来需深入研究以明确其治疗机制并建立标准化方案,为LRP提供更安全有效的治疗选择。 展开更多
关键词 富血小板血浆 神经根性腰痛 硬膜外注射 神经修复 炎症调节 椎间孔注射
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