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中药有效成分调节机体脂代谢作用的研究进展

中草药 2024年第9期55卷 3127-3136页

作者：杨玉涛张冠宇杨丹凤张永强张莉武帅李曦周玉枝山西大学中医药现代研究中心山西太原030006 军事科学院军事医学研究院天津300050

脂质代谢作为机体重要且复杂的生命过程,对生命活动具有重要意义。脂代谢的紊乱可直接引发酮症、脂肪肝、肥胖等代谢性疾病。中药因多靶点、多途径、不良反应相对较少等优点被广泛应用于脂代谢方面的研究,且中药在治疗肥胖等与脂质代谢... 详细信息

脂质代谢作为机体重要且复杂的生命过程,对生命活动具有重要意义。脂代谢的紊乱可直接引发酮症、脂肪肝、肥胖等代谢性疾病。中药因多靶点、多途径、不良反应相对较少等优点被广泛应用于脂代谢方面的研究,且中药在治疗肥胖等与脂质代谢紊乱相关的疾病方面历史悠久、临床疗效确切。通过对近年来中药有效成分在调节脂肪组织结构和功能方面的研究进行整理归纳,为中药药理学研究及中药的新药开发、老药新用提供新思路。

关键词：中药脂代谢脂肪组织脂肪细胞丹参酮Ⅰ 黄芩苷小檗碱

Impacts of heterogeneous CO_(2)on water and carbon fluxes across the global land surface

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International Journal of Digital Earth 2021年第9期14卷 1175-1193页

作者： Jing Tian yongqiang zhang Xuanze zhang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research(IGSNRR)Chinese Academy of Sciences(CAS)BeijingPeople’s Republic of China

Over the recent decades,the increase of atmospheric carbon dioxide(CO_(2))concentration has caused large effects on the earth ***,few studies have paid attention to the effects of heterogeneity of CO_(2)on the biosphere and the *** a coupled diagnostic biophysical model(PML-V2)and comparing three heterogeneous CO_(2)datasets(GOSAT,CMIP6 and CarbonTracker)against a baseline homogeneous data(ESRL),this study investigated the effects of heterogeneous CO_(2)on gross primary production(GPP),actual evapotranspiration(ET)and water use efficiency(WUE)across the *** results show that among the three heterogeneity CO_(2),CarbonTracker produced the highest CO_(2)concentration and showed the largest difference in ET(−6%to 2%),GPP(−2%to 5%)and WUE(4%to 11%)compared to those from the *** most effects of the CO_(2)heterogeneity occurred in *** was identified as a vulnerable region with prominent decrease in GPP and an increase in ET due to CO_(2)*** obvious increase in GPP and a decrease in ET appeared in the Amazon rainforest,the Congo rainforest,and eastern *** global scale,the effects of the CO_(2)heterogeneity on ET/GPP/WUE were not significant.

关键词： Global CO_(2)heterogeneity evapotranspiration gross primary production water use efficiency

Computing environmental life of electronic products based on failure physics

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Journal of Systems Engineering and Electronics 2016年第2期27卷 493-500页

作者： yongqiang zhang Zongchang Xu Chunyang Hu Academy of Armored Force Engineering Beijing 100072China Naval Air Force Institute Liaoning 125000China

In some situations, the accelerated life test on environmental stress for electronic products is not easily implemented due to various restrictions, and thus engineers are lacking of data of the product life test. Concerning this problem, environmental life of the printed circuit board（PCB） board is calculated by way of physics of failure. Influences of thermal cycle and vibration on PCB and its components are studied. Based on the analysis of force and stress between components and the PCB board in thermal cycle events and vibration events, four life computing models of pins and soldered dots are established. The miller damage ratio is used to calculate the accumulated damage of a pin or a soldered dot, and then the environment life of the PCB board can be determined by the first failed one. Finally, an example is used to illustrate the models and their calculations.

关键词： environmental life pins soldered dots printed cir-cuit board(PCB)

激素受体阳性/人表皮生长因子受体2阳性晚期乳腺癌生物学特点及治疗进展

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中国医学前沿杂志（电子版） 2024年第4期16卷 73-80页

作者：刘德桐李超许焱丁丽张永强北京医院肿瘤科国家老年医学中心、中国医学科学院老年医学研究院北京100730 北京协和医学院研究生院、中国医学科学院北京100730

激素受体阳性(hormone receptor-positive,HR+)/人表皮生长因子受体2阳性(human epidermal growth factor receptor 2-positive,HER2+)晚期乳腺癌是一种异质性较高的肿瘤亚型,各大指南对于HER2+晚期乳腺癌,不论HR阳性或阴性,均建议在抗HER2治疗基础上首选联合化疗,专门针对HR+/HER2+晚期乳腺癌的临床研究不多,其最佳治疗特别是后线治疗选择仍存在争议。晚期乳腺癌很难治愈,兼顾不同治疗手段比如化疗与内分泌治疗的疗效和患者的生活质量等显得非常重要。加之近几年针对HR+的细胞周期蛋白依赖性激酶4/6 (cyclin-dependent kinase 4/6 inhibitor,CDK4/6)抑制剂等靶向药物和针对HER2+乳腺癌的新型抗HER2靶向药物和抗体药物偶联物(antibody-drug conjugate,ADC)的应用,为HR+/HER2+晚期乳腺癌的治疗带来了诸多选择和疗效以及安全性的不确定性。本文综述HR+/HER2+晚期乳腺癌分子生物学和临床病理特点、研究进展和治疗选择,为临床医生治疗决策提供参考。

关键词：晚期乳腺癌激素受体阳性人表皮生长因子受体2阳性生物学特点治疗进展

近二十年鄂尔多斯气象干旱与生态干旱的空间分布及其传递关系

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地理研究 2024年第7期43卷 1878-1890页

作者：田小强邵杏敏张永强冯瑞吴桐境陈兵边楠鄂尔多斯市水旱灾害防御技术中心鄂尔多斯017000 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 中国科学院大学北京100049

干旱是鄂尔多斯最严重的自然灾害之一。然而鄂尔多斯气象干旱和生态干旱的空间分布情况及其传递关系尚不明晰。本文采用高分辨率的降水数据与植被总初级生产力数据,全面分析2000-2020年鄂尔多斯四类自然生态系统气象干旱特征和生态干旱... 详细信息

干旱是鄂尔多斯最严重的自然灾害之一。然而鄂尔多斯气象干旱和生态干旱的空间分布情况及其传递关系尚不明晰。本文采用高分辨率的降水数据与植被总初级生产力数据,全面分析2000-2020年鄂尔多斯四类自然生态系统气象干旱特征和生态干旱特征的空间分布,并进一步量化气象干旱与生态干旱的传递关系。结果显示:鄂尔多斯气象干旱和生态干旱的频率分别为0.26次/年和0.13次/年,干旱传递频率高;两种干旱类型的历时均表现为西低东高,且具有较好相关性;但两者强度相关性较弱。四类生态系统的气象干旱强度相近。其中,森林生态干旱强度最低,高覆盖度草地生态干旱强度最高。该研究可为鄂尔多斯生态环境保护和抗旱管理措施制定提供科学依据。

关键词：气象干旱生态干旱干旱传递鄂尔多斯生态系统

非学科类校外培训能让儿童更好适应学校生活吗——基于非认知能力的中介效应分析

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现代教育论丛 2024年第4期 55-68页

作者：张永强赵佶旺东北农业大学公共管理与法学院黑龙江哈尔滨150030

“双减”背景下探究非学科校外培训对儿童学校适应的影响有助于社会对非学科培训进行更加合理科学的判断与选择。基于中国教育追踪调查数据,使用固定效应模型考察非学科培训与学校适应的关系,结果表明:参与非学科校外培训对学校适应具... 详细信息

“双减”背景下探究非学科校外培训对儿童学校适应的影响有助于社会对非学科培训进行更加合理科学的判断与选择。基于中国教育追踪调查数据,使用固定效应模型考察非学科培训与学校适应的关系,结果表明:参与非学科校外培训对学校适应具有显著正向影响,且具有稳健性;异质性分析发现,非学科校外培训对非流动儿童、家境较好儿童以及成绩中等以下的儿童具有显著正向影响,对流动儿童、家境较差儿童以及成绩较好的儿童没有显著影响;非学科校外培训会通过非认知能力中的亲和性、外向性和开放性来改善儿童的学校适应状况。家长可以根据子女实际状况和兴趣为他们选择兴趣班,校外教育机构需要为有特殊家庭背景的儿童提供定制化服务项目,政府则要引导学校与校外非学科教育在课后服务领域开展深层次合作,以缩小在非学科培训和课后服务上造成的不平等。

关键词：非学科培训学校适应非认知能力

Separating impacts of vegetation change and climate variability on streamflow using hydrological models together with vegetation data

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Science China(Technological Sciences) 2012年第7期55卷 1964-1972页

作者： LI HuiYun zhang yongqiang WANG BenDe Nanjing Institute of Geography ＆ Limnology Chinese Academy of Sciences Nanjing 210008 China CSIRO Land and Water GPO BOX 1666 CanberraACT 2601 Australia Faculty of Infrastructure Engineering Dalian University of Technology Dalian 116024 China

Vegetation information is seldom considered in lumped conceptual rainfall-runoff *** paper uses two modified rainfall-runoff models,the Xinanjiang-ET and SIMHYD-ET models in which vegetation leaf area index is incorporated,to investigate impacts of vegetation change and climate variability on streamflow in a Southern Australian catchment,the Crawford River experimental catchment,where Tasmanian blue gum plantations were introduced gradually from 1998 till *** Xinanjiang-ET and SIMHYD-ET models incorporate remotely-sensed leaf area index(LAI) data obtained from the Advanced Very High Resolution Radiometer(AVHRR) on board NOAA polar orbiting *** to the original versions,the Xinanjiang-ET and SIMHYD-ET models show marginal improvements in runoff simulations in the pre-plantation period(1882-1997).The calibrated Xinanjaing-ET and SIMHYD-ET models are then used to simulate plantation impact on streamflow in the post-plantation *** total change in streamflow between the pre-plantation and post-plantation periods is 32.4 mm/*** modelling results from the two models show that plantation reduces streamflow by 20.5 mm/a,and climate variability reduces streamflow by 11.9 mm/*** results suggest that increase in plantations can reduce streamflow substantially,even more than climate variability.

关键词： vegetation change climate variability streamflow leaf area index hydrological model Crawford River

Climate change detection and attribution in the Ganga-Brahmaputra-Meghna river basins

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Geoscience Frontiers 2021年第5期12卷 192-201页

作者： Chetan Sharma Anoop Kumar Shukla yongqiang zhang Civil Engineering Department JIETJodhpurRajasthanIndia Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Ganga-Brahmaputra-Meghna(GBM)river basin is the third-largest and one of the most populated river basins in the *** climate change is affecting most of the hydrometeorological variables across the globe,this study investigated the existence of climate change signal in all four climatological seasons in the GBM river basin and assessed the contribution of anthropogenic activities,i.e.,Greenhouse Gases(GHGs)emission in the *** decreasing trends in the monsoon and a small increase in pre-monsoon precipitation were *** change was detected in post-monsoon and winter season ***5 GCMs were used for climate change detection,change point estimation,and attribution *** Vector Machine(SVM)regression method was adopted to downscale GCM variables at the local ***-Carlo simulation approach was used to detect changes in different *** climate change‘signals’were detectable after the year 1980 using Signal to Noise ratio(SNR)method in the majority of central and north-western *** change point was detectable only in annual monsoon precipitation at the basin *** analysis indicated>50%contribution of anthropogenic activities(GHGs)to annual monsoon precipitation ***,there is high confidence that monsoon precipitation in GBM has significantly changed due to anthropogenic *** mitigation and adaption measures are also suggested,which may be adopted to manage the growing demand and water availability in the basin.

关键词： Ganga-Brahmaputra-Meghna(GBM) Climate change Support vector machine Signal to noise ratio Anthropogenic activities

Multi-band design for one-dimensional phononic crystals

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Science China(Physics,Mechanics & Astronomy) 2013年第7期56卷 1253-1262页

作者： zhang Pei WANG ZhenYu zhang yongqiang LIANG Xu College of Civil Engineering and Architecture Zhejiang University

Periodic composites with band gaps that prevent the propagation of elastic waves in certain frequency ranges can be used to control waves for a variety of engineering applications. Although studies on the characteristics of these materials, which are called phononic crystals (PCs), have yielded a large number of positive results in recent years, there is still a lack of effective design methods. In this work, a multi-objective optimization approach based on the band gap mechanism and an intelligent algorithm is used to design a one-dimensional (1D) slab construction of PCs. The design aims to fit pre-determined bands by arranging the available materials properly. Obtained by analyzing the wave transmission in periodic layers, the objective functions are linked to the optimization program to obtain a proper solution set. The results of the numerical simulations demonstrate that without constructing complicated structures, the design method is able to produce PCs that overcome the limitations of two-component PCs and hence can feasibly and effectively achieve the design targets. The design approach presented in this paper can be extended to two-or three-dimensional systems and has great potential for the development of sound/ultrasound isolation structures, multiple band frequency filters, and other applications.

关键词： phononic crystals multi-band design multi-objective optimization