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Abrupt vegetation shifts caused by gradual climate changes in central Asia during the Holocene

Science China Earth Sciences 2017年第7期60卷 1317-1327页

作者： ZHAO Yan liu yaoliang GUO ZhengTang FANG KeYan LI Quan CAO XianYong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China College of Geographical Sciences Fujian Normal University Fuzhou 350007 China Alfred Wegener Institute Helmholtz Center for Polar and Marine Research 14473 Potsdam Germany

Understanding the response of ecosystems to past climate is critical for evaluating the impacts of future climate changes.A large-scale abrupt shift of vegetation in response to the Holocene gradual climate changes has been well documented for the Sahara-Sahel ecosystem. Whether such a non-linear response is of universal significance remains to be further addressed. Here,we examine the vegetation-climate relationships in central Asia based on a compilation of 38 high-quality pollen records. The results show that the Holocene vegetation experienced two major abrupt shifts, one in the early Holocene(Shift I, establishing shift) and another in the late Holocene(Shift II, collapsing shift), while the mid-Holocene vegetation remained rather stable. The timings of these shifts in different regions are asynchronous, which are not readily linkable with any known abrupt climate shifts,but are highly correlated with the local rainfalls. These new findings suggest that the observed vegetation shifts are attributable to the threshold effects of the orbital-induced gradual climate changes. During the early Holocene, the orbital-induced precipitation increase would have first reached the threshold for vegetation "establishment" for moister areas, but significantly later for drier areas. In contrast, the orbital-induced precipitation decrease during the late Holocene would have first reached the threshold, and led to the vegetation "collapse" for drier areas, but delayed for moister areas. The well-known 4.2 kyr BP drought event and human intervention would have also helped the vegetation collapses at some sites. These interpretations are strongly supported by our surface pollen-climate analyses and ecosystem simulations. These results also imply that future climate changes may cause abrupt changes in the dry ecosystem once the threshold is reached.

关键词： Fossil pollen Vegetation response Threshold effects Holocene climate Central Asia

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1例牛卵形巴贝斯虫与嗜吞噬细胞无浆体混合感染的诊断

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现代畜牧科技 2024年第9期 95-97页

作者：田万年郑秀红刘耀亮李齐吉林农业科技学院动物科技学院吉林昌邑132101 吉林省龙井市德新乡综合服务中心吉林龙井133400 吉林省和龙市科技信息服务中心吉林和龙133500

2023年6月,吉林省图们市某牛场黄牛出现贫血、消瘦、反刍障碍和血红蛋白尿等症状。为分析病牛的发病原因,对其进行临床初步诊断和PCR检测。PCR检测结果显示,卵形巴贝斯虫和嗜吞噬细胞无浆体均为阳性。系统进化分析显示,试验获得的卵形... 详细信息

2023年6月,吉林省图们市某牛场黄牛出现贫血、消瘦、反刍障碍和血红蛋白尿等症状。为分析病牛的发病原因,对其进行临床初步诊断和PCR检测。PCR检测结果显示,卵形巴贝斯虫和嗜吞噬细胞无浆体均为阳性。系统进化分析显示,试验获得的卵形巴贝斯虫吉林株与日本株亲缘关系较近;嗜吞噬细胞无浆体吉林株与韩国株亲缘关系较近。该文为吉林省牛卵形巴贝斯虫病和嗜吞噬细胞无浆体病的综合防治提供理论依据。

关键词：卵形巴贝斯虫嗜吞噬细胞无浆体诊断

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Relative pollen productivities of typical steppe species in northern China and their potential in past vegetation reconstruction

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Science China Earth Sciences 2014年第12期57卷 1254-1266页

作者： XU QingHai CAO XianYong TIAN Fang ZHANG ShengRui LI YueCong LI ManYue LI Jie liu yaoliang LIANG Jian Institute of Nihewan Archaeology Hebei Normal University College of Resources and Environment Science Hebei Normal University Hebei Key Laboratory of Environmental Change andEcological Construction Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Research Unit Potsdam Potsdam 14473 Germany Institute of Earth and Environmental Sciences University of Potsdam

The Relative Pollen Productivities(RPPs)of common steppe species are estimated using Extended R-value(ERV)model based on pollen analysis and vegetation survey of 30 surface soil samples from typical steppe area of northern ***,Chenopodiaceae,Poaceae,Cyperaceae,and Asteraceae are the dominant pollen types in pollen assemblages,reflecting the typical steppe communities *** five dominant pollen types and six common types(Thalictrum,Iridaceae,Potentilla,Ephedra,Brassicaceae,and Ulmus)have strong wind transport abilities;the estimated Relevant Source Area of Pollen(RSAP)is ca.1000 m when the sediment basin radius is set at 0.5 ***,Artemisia,Brassicaceae,Chenopodiaceae,and Thalictrum have relative high RPPs;Poaceae,Cyperaceae,Potentilla,and Ephedra pollen have moderate RPPs;Asteraceae and Iridaceae have low *** reliability test of RPPs revealed that most of the RPPs are reliable in past vegetation ***,the RPPs of Asteraceae and Iridaceae are obviously underestimated,and those of Poaceae,Chenopodiaceae,and Ephedra are either slightly underestimated or slightly overestimated,suggesting that those RPPs should be considered with *** RPPs were applied to estimating plant abundances for two fossil pollen spectra(from the Lake Bayanchagan and Lake Haoluku)covering the Holocene in typical steppe area,using the"Regional Estimates of Vegetation Abundance from Large Sites"(REVEALS)*** RPPs-based vegetation reconstruction revealed that meadow-steppe dominated by Poaceae,Cyperaceae,and Artemisia plants flourished in this area before 6500–5600 cal yr BP,and then was replaced by present typical steppe.

关键词： typical steppe modern surface pollen relative pollen productivity relevant pollen source area paleovegetation

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合力教育拓展幸福的探索与实践

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中国特殊教育 2011年第9期 65-68页

作者：林群柳耀亮宁波市鄞州区华泰小学宁波315105

育人工作是一个全方位的系统工作,需要学校、家庭、社会各方面的互相配合。在构建幸福学校背景下,积极探索幸福的育人模式,切实提高学校教育的实效性,成为当前中小学一项非常紧迫的任务。文章以浙江省鄞州区华泰小学为例,站在新时期的高... 详细信息

育人工作是一个全方位的系统工作,需要学校、家庭、社会各方面的互相配合。在构建幸福学校背景下,积极探索幸福的育人模式,切实提高学校教育的实效性,成为当前中小学一项非常紧迫的任务。文章以浙江省鄞州区华泰小学为例,站在新时期的高度,探讨如何有效开展家校合作,如何充分整合利用家庭、社区、社会的教育资源,发挥家长、社会人员的教育作用从而形成教育合力,为缔造学生幸福有成的人生奠基。

关键词：合力教育家校社区社会幸福成长

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高浓度草酸作用下HK-2细胞系中外泌体的提取与鉴定

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中华泌尿外科杂志 2017年第9期38卷 712-716页

作者：何子奇关晓峰刘权刘云龙邓耀良广西医科大学第一附属医院泌尿外科 530021

目的探讨高浓度草酸作用下HK-2细胞系中外泌体提取与鉴定的方法.方法 2016年6月至2017年1月进行实验.配制含草酸浓度分别为0、0.25、0.50、1.00、2.00、4.00、5.00、8.00、10.00mmoL/L的DMEM/F12无血清培养基,分别对HK-2细胞干预48 h,... 详细信息

目的探讨高浓度草酸作用下HK-2细胞系中外泌体提取与鉴定的方法.方法 2016年6月至2017年1月进行实验.配制含草酸浓度分别为0、0.25、0.50、1.00、2.00、4.00、5.00、8.00、10.00mmoL/L的DMEM/F12无血清培养基,分别对HK-2细胞干预48 h,然后用CCK-8法检测不同浓度草酸对HK-2细胞生存率的影响.结合倒置显微镜下观察细胞的形态学变化,选择2.00 mmol/L的草酸作为实验浓度.用2.00 mmol/L草酸对HK-2细胞系干预48 h,收集干预后的HK-2细胞系的上清液,采用超速离心法提取外泌体;透射电镜观察外泌体的形态、大小;Nanosight系统检测外泌体的粒径与分布;蛋白质印迹法检测外泌体特异性蛋白HSP70、CD63的表达.结果 CCK-8法检测结果显示0、0.25、0.50、1.00、2.00、4.00、5.00、8.00、10.00 mmol/L组细胞的生存率分别为（100.0±4.0）％、（97.7±1.5）％、（97.3±2.1）％、（87.7±2.1）％、（76.0±1.0）％、（58.1±2.6）％、（52.7±1.5）％、（37.7±3.2）％、（31.3±2.0）％.透射电镜下外泌体呈杯口状,包膜为典型的双层膜结构.Nanosight系统显示2.00mmoL/L组外泌体峰值粒径为56 nm,整体平均粒径为87 nm,粒径为30～150 nm的比例为91.2％.蛋白质印迹法检测结果显示外泌体中明显表达HSP70和CD63蛋白,提取外泌体后的HK-2细胞表达HSP70蛋白,不表达CD63蛋白.结论 2.00 mmol/L草酸作用HK-2细胞48 h后,可以通过超速离心法提取丰富的、较高纯度的外泌体,这将为后续深入研究高浓度草酸背景下外泌体的信号转导奠定基础.

关键词：外泌体肾结石草酸

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3,5-二羟基苯甲酸酯疏松纳滤膜的制备及染料/盐分离性能研究

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塑料工业 2024年第2期52卷 112-119,152页

作者：郑阿龙刘大朋洪耀良苏州科技大学环境科学与工程学院江苏苏州215009 江苏省分离净化材料与技术工程研究中心江苏苏州215009 江苏省水处理技术与材料协同创新中心江苏苏州215009

为提高膜对印染废水的染料/盐分离效果,以3,5-二羟基苯甲酸为单体,通过低反应活性的羟基与均苯三甲酰氯(TMC)反应,在聚醚砜底膜表面通过界面聚合(IP)制备了新型聚酯疏松纳滤膜。对聚酯复合膜的化学组成、表面性质、表面形貌进行了表征,... 详细信息

为提高膜对印染废水的染料/盐分离效果,以3,5-二羟基苯甲酸为单体,通过低反应活性的羟基与均苯三甲酰氯(TMC)反应,在聚醚砜底膜表面通过界面聚合(IP)制备了新型聚酯疏松纳滤膜。对聚酯复合膜的化学组成、表面性质、表面形貌进行了表征,阐述了复合膜的结构性能关系,研究了不同的制备条件对复合膜的性能影响。在3,5-二羟基苯甲酸、氢氧化钠、均苯三甲酰氯质量分数分别为0.3%、0.2%、0.1%,界面聚合1 min的条件下,聚酯复合膜具有超高渗透性[水通量77.74 L/(m^(2)·h·bar)]、高染料截留率(刚果红,99.64%;直接红23,98.48%)和高盐渗透率(氯化钠,91.51%;硫酸钠,85.63%)。在2 bar压力下对染料/盐混合溶液进行5 h的过滤实验,所制复合膜表现出优异的防污性和运行稳定性。

关键词：疏松纳滤界面聚合 3,5-二羟基苯甲酸染料/盐分离聚醚砜

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麦芽糖醇基聚酯复合纳滤膜的制备及性能

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膜科学与技术 2024年第3期44卷 133-142页

作者：张全合刘大朋洪耀良苏州科技大学环境科学与工程学院苏州215009 江苏省分离净化材料与技术工程研究中心苏州215009 江苏省水处理技术与材料协同创新中心苏州215009

疏松纳滤膜具有良好的染料/盐选择分离性,有望满足纺织废水处理中对染料/盐混合物分离的迫切需要。本文以具有丰富羟基的麦芽糖醇(Maltitol)为新型水相单体,通过与均苯三甲酰氯(TMC)在聚醚砜(PES)超滤膜表面界面聚合(IP),制备了具有高染... 详细信息

疏松纳滤膜具有良好的染料/盐选择分离性,有望满足纺织废水处理中对染料/盐混合物分离的迫切需要。本文以具有丰富羟基的麦芽糖醇(Maltitol)为新型水相单体,通过与均苯三甲酰氯(TMC)在聚醚砜(PES)超滤膜表面界面聚合(IP),制备了具有高染料/盐选择性和高透水通量的Maltitol/TMC疏松纳滤膜,用于染料/盐组分的高效分离.通过调节麦芽糖醇的浓度对膜的性能进行优化,优化后的膜纯水通量达800.1 L/(m^(2)·h·MPa),对刚果红(CR)、直接红23(DR 23)和铬黑T(EBT)的截留率分别为99.3%、95.1%和97.2%,对Na2SO4和NaCl截留率分别仅为10.3%和4.4%.优化膜对3种染料的通量恢复率(FRR)均在90%左右,同时对染料/盐混合溶液具有良好的运行稳定性.这些结果表明,该新型麦芽糖醇基纳滤膜在纺织废水处理中具有良好的应用前景.

关键词：疏松纳滤膜界面聚合麦芽糖醇染料/盐分离

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Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 275-286页

作者： Haoyu liu Chongru liu North China Electric Power University Beijing 102206China

Frequency regulation of voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC)system with offshore wind farms enhances the frequency stability by compensating the power for a disturbed AC ***,it is difficult to reasonably allocate frequency-regulation resources due to a lack of coordination mechanisms between wind farms and the MTDC ***,it is difficult for the frequency control of the wind farms to manage changes in wind speed;and the risk of wind-turbine stalls is ***,based on the kinetic energy of wind turbines and the power margin of the converters,the frequency-regulation capability of wind turbines is evaluated,and a dynamic frequency-support scheme considering the real-time frequency-support capability of the wind turbines and system frequency evolution is proposed to improve the frequency-support performance.A power adaptation technique at variable wind speeds is developed;the active power in the frequency-support stage and restoration stage is switched according to the wind speed.A hierarchical zoning frequency-regulation scheme is designed to use the frequency-regulation resources of different links in the MTDC system with wind *** simulation results show that the novel frequency-regulation strategy maintains frequency stability with wind-speed changes and avoids multiple frequency dips.

关键词： Wind generation voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC) frequency regulation cooperative control adaptive control variable wind speed

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A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

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Effectiveness and safety of acupuncture in treatment of pregnancyrelated symptoms:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 16-26页

作者： liu Tingting liu Tongou liu Mingfu School of Traditional Chinese Medicine Clinical Medicine Hubei University of Traditional Chinese MedicineWuhan 430000China First Clinical College of Hubei University of Traditional Chinese Medicine Wuhan 430000China Department of Acupuncture and Tuina Affiliated Hospital of Hubei University of Traditional Chinese MedicineHubei Provincial Hospital of Traditional Chinese MedicineWuhan 430000China

OBJECTIVE:To systematically evaluate the efficacy and safety of acupuncture(AM)in the treatment of pregnancyrelated symptoms such as acute vomiting during ***:We comprehensively searched the available literature up to November 2021,including Pub Med,Embase,Cochrane Library,Chinese Biomedical Literature Database,and China National Knowledge Infrastructure Database,for randomized controlled trials(RCTs)on AM for the treatment of severe vomiting,insomnia,pharyngeal and pelvic pain,mood abnormalities,and dyspepsia during ***:Sixteen RCTs with a cumulative sample size of 1178 cases were *** these,964 patients were included in the *** Meta-analysis results showed that AM was more efficient than Western medicine in treating discomfort during pregnancy[odds ratio(OR)=1.19,95%confidence interval(CI)(1.11,1.28),P<0.01].AM was better than the control group in improving the visual analog scale scores[standard mean difference(SMD)=0.62,95%CI(0.53,0.71),P<0.01].AM was superior to the control group in improving Numerical Rating Scale(NRS)symptom scores[OR=7.31,95%CI(3.36,15.94),P<0.01].There was no significant difference in adverse effects between the AM and sham-AM groups and the analgesic drug group[OR=0.70,95%CI(0.39,1.28),P=0.25],but the treatment and control groups had mild adverse effects with a low ***:AM is more effective than other treatments or pharmacotherapy alone in the treatment of pregnancy-related symptoms,and is relatively ***,the quality of the included trials was rather poor,and high-quality studies are required to confirm our findings.

关键词： acupuncture pregnancy nausea vomiting sleep initiation and maintenance disorders low back pain pelvic pain mood abnormalities Meta-analysis systematic review

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