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Geotextile protection of glacier:Observed and simulated impacts on energy and mass balance

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Advances in Climate Change Research 2023年第6期14卷 963-975页

作者： Fei-Teng WANG Shuang-Shuang LIU Xing WANG Hui-Lin LI chun-hai xu Lin WANG Yu-Ang xuE Xiao-Ying YUE State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The detailed physical processes involved in slowing glacier ablation by material cover remain poorly understood so *** the present study,using the snow cover model SNOWPACK,the effect of geotextile cover on the energy and mass balance at the tongue of the Urumqi Glacier No.1(Chinese Tien Shan)was simulated between July 12,2022 and August 31,*** mass changes and the energy fluxes with and without material cover were *** results indicated that the geotextile covering reduced glacier ablation by approximately 68%compared to the ablation in the uncovered *** high solar reflectivity of the geotextile reduced the net short-wave radiation energy available for the melt by 45%.Thermal insulation of the geotextile reduced the sensible heat flux by 15%.In addition,the wet geotextile exerted a cooling effect through long-wave radiation and negative latent heat *** cooling effect reduced the energy available for ablation by 20%.Consequently,only 37%of the energy was used for melting compared to that used in the uncovered regions(67%).Sensitivity experiments revealed that the geotextile cover used at a thickness range of 0.045-0.090 m reduced the ice loss by approximately 68%-72%,and a further increase in the thickness of the geotextile cover led to little improvements.A higher temperature and greater wind speed increased glacier ablation,although their effects were *** the precipitation was set to zero,it led to a significantly increased ***,the geotextile effectively protected the glacier tongue from rapid melting,and the observed results have provided inspiration for developing an effective and sustainable approach to protect the glaciers using geotextile cover.

关键词： Artificial melt reduction SNOWPACK Geotextile Energy and mass balance Urumqi glacier No.1 Chinese Tien Shan

Do abrupt cryosphere events in High Mountain Asia indicate earlier tipping point than expected?

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Advances in Climate Change Research 2023年第6期14卷 873-883页

作者： Cun-De XIAO Tong ZHANG Tao CHE Zhi-Qiang WEI Tong-Hua WU Lei HUANG Ming-Hu DING Qiao LIU Dong-Hui SHANGGUAN Fei-Teng WANG Peng-Ling WANG Jie CHEN chun-hai xu Xin-Wu xu Da-He QIN State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China State Key Laboratory of Cryospheric Science Chinese Academy of SciencesLanzhou 730000China Faculty of Arts and Sciences Beijing Normal UniversityZhuhai 519000China National Climate Centre China Meteorological AdministrationBeijing 100081China Global Change and Polar Institute Chinese Academy of Meteorological ScienceBeijing 100081China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China

Tipping points of about 16 elements have been identified in Earth system,yet cryospheric tipping point of specific Alpine region has not been *** we analyzed three tipping elements(mountain glacier,snow cover,and permafrost)identified in recent years,evidenced by the facts of frequent occurrence of abrupt massive collapse of glacier mass and the widespread thermakarst of *** 2015,strikingly abrupt cryosphere events(ACEs)have been consistently observed over a large range of High Mountain Asia(HMA).Those events were un-precedentedly significant in history,leading to collapses of glaciers following by disconnection of glacier tongue from accumulation basin and recession of thermakarst towards higher *** decreasing of snow depth in 2022 was also observed since 2021/2022 winter,coinciding with extreme warming of the *** widespread high warming rates in the last two decades over HMA might have triggered above *** dynamic thresholds of ACEs depend largely on high temperature,especially extreme heat wave,for both glaciers and permafrost,closely related to meltwater as a key factor for reaching initial conditions of abrupt changes,suggesting HMA cryosphere is a tipping element under the global warming level of 1.1℃.The ACEs can cause tremendous damage to local ecosystem and socioeconomy,measures to mitigate risks should be taken when the tipping points are reached.

关键词： Abrupt glacier change Thermakarst Snow depth Tipping point Early warning system

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窒息性毒(战)剂中毒损伤防治研究进展

军事医学 2012年第6期36卷 406-410页

作者：海春旭第四军医大学军事预防医学院军事毒理学教研室特殊作业环境危害评估与防治教育部重点实验室陕西省自由基生物学与医学重点实验室西安710032

本文从窒息性毒剂的危害特点与一般临床表现及中毒后的预后规律总结概述了窒息性毒剂的总体发展态势,通过归纳典型窒息性战剂——光气的中毒背景、病理改变,探讨光气中毒机制和防护措施的研究进展,将有利于认识窒息性毒剂在化学损伤中... 详细信息

本文从窒息性毒剂的危害特点与一般临床表现及中毒后的预后规律总结概述了窒息性毒剂的总体发展态势,通过归纳典型窒息性战剂——光气的中毒背景、病理改变,探讨光气中毒机制和防护措施的研究进展,将有利于认识窒息性毒剂在化学损伤中的重要地位,推动建立新的军事医学研究模式,深入研究其防治措施,打造防化医学新前沿。

关键词：窒息性毒剂光气气体中毒解毒药

EFFECT OF VITAMIN A AND VITAMIN E DIETARY SUPPLEMENTATION ON RADIATION INJURY OF RATS

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EFFECT OF VITAMIN A AND VITAMIN E DIETARY SUPPLEMENTATION ON...

低浓度叔丁基过氧化氢对小鼠胚肺成纤维细胞L929增殖作用的影响

The Second International Symposium on Natural Antioxidants: Molecular Mechanisms and Health Effects

作者： Qin xu-jun, hai chun-xu, Wang LuDepartmant of hygienic toxicology, The Fourth Military Medical University Xi'an (710032) China.

We hypothesized that vitamin A could utilize vitamin E during the process against oxidative injury. Reactive oxygen species (ROS) generated during radiation play an important role in radiation injury. In this study, the radiated rats were chosen to be ideal oxidative injury model induced by free radicals to learn the function of vitamin A and vitamin E and the interaction between them during the oxidative injury. The rats were randomly divided

关键词： radiation, vitamin A, vitamin E, Reactive Oxygen Species (ROS)

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中国微循环 2008年第1期12卷 26-29页

作者：王晓礽海春旭第四军医大学军事预防医学系毒理学教研室陕西西安710032

目的通过不同浓度的叔丁基过氧化氢(Tert-Butyl bydroperoxide,TBHP)作用于培养的小鼠胚肺成纤维细胞系L929细胞,观察低浓度的TBHP对细胞生长、增殖的影响。方法按TBHP的终浓度从低到高分别为:空白组(0μmol/L)、低浓度组(1μmol/L)、... 详细信息

目的通过不同浓度的叔丁基过氧化氢(Tert-Butyl bydroperoxide,TBHP)作用于培养的小鼠胚肺成纤维细胞系L929细胞,观察低浓度的TBHP对细胞生长、增殖的影响。方法按TBHP的终浓度从低到高分别为:空白组(0μmol/L)、低浓度组(1μmol/L)、中浓度组(10μmol/L)和高浓度组(40μmol/L)分成四组。通过破壁灵芝孢子粉水提液(2.0g/L)作用L929细胞系24h,使细胞同步化,分别加入相应浓度的TBHP溶液。用MTT比色法检测细胞活力,并以溴脱氧尿嘧啶核苷(bromode-oxyuridine,BrdU)的免疫荧光染色法观察各组细胞的增殖变化,同时在相差显微镜下观察细胞的形态学变化。结果镜下观察发现,TBHP1μmol/L组细胞密度高于空白组和中、高浓度组,且BrdU阳性细胞数目最多,细胞生长旺盛;MTT结果显示TBHP1μmol/L组OD值最高,其次为空白组和中浓度组,高浓度组最低(P<0.01),BrdU阳性荧光显色主要在刚刚分裂完成的细胞,呈现"镜像性"改变。结论低浓度TBHP对体外培养L929细胞的增殖、生长具有一定促进作用,BrdU阳性荧光显色细胞的"镜像性"改变是反映细胞增殖活性的有效判定指标。

关键词：叔丁基过氧化氢 L929 ROS 增殖

维生素A,E,C对大鼠肝微粒体LPO模型的影响

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第四军医大学学报 2008年第10期29卷 896-899页

作者：赵海龙刘瑞梁欣海春旭第四军医大学军事预防医学系毒理学教研室陕西西安710033

目的：探讨维生素A,E,C（VA,VE,VC）的抗氧化作用及其剂量反应关系.方法：钙沉淀法提取雄性SD大鼠肝微粒体.采用四氯化碳（CCl4）,Vc/Fe2＋和过氧基异丙苯（CHP）三种激发剂建立大鼠肝微粒体脂质过氧化（LPO）模型,比色法测定丙二醛（MD... 详细信息

目的：探讨维生素A,E,C（VA,VE,VC）的抗氧化作用及其剂量反应关系.方法：钙沉淀法提取雄性SD大鼠肝微粒体.采用四氯化碳（CCl4）,Vc/Fe2＋和过氧基异丙苯（CHP）三种激发剂建立大鼠肝微粒体脂质过氧化（LPO）模型,比色法测定丙二醛（MDA）含量,观察VA,VE和VC三种维生素对MDA的抑制作用.结果：VA浓度在25~100μmol/L范围时,对三种模型中各浓度组MDA的含量均有抑制作用,最高抑制率分别为（81.2±8.6）%,（98.1±13.8）%和（85.1±2.4）%,显著低于对照组（P〈0.05）,在CHP模型中,VA浓度在10μmol/L时其MDA的含量升高.VE浓度在100~1000μmol/L范围时,CCl4和Vc/Fe2＋两种模型各浓度组的MDA含量均显著低于对照组（P〈0.05）,最高抑制率分别为（62.3±5.5）%和（95.5±7.4）%;在CHP模型中,当VE浓度在750-1000μmol/L时其MDA含量降低;最高抑制率仅为（18.7±2.1）%.VC浓度在2500μmol/L时,三种模型的MDA含量均显著低于对照组（P〈0.05）;最高抑制率分别为（83.6±5.9）%,（25.0±3.0）%和（90.4±7.8）%.结论：VA,VE和VC在三个模型中均有较强的抗氧化作用,且存在一定的剂量效应关系,其中VA抗氧化能力更强.

关键词：维生素A 维生素E 抗坏血酸抗氧化作用脂质过氧化作用

Nrf2 protectsβcell against lipotoxicity via regulating multiple antioxidant enzymes

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Nrf2 protectsβcell against lipotoxicity via regulating mult...

原子吸收光谱法测定血清中不同化学形态的铜、铁、锌

中国活性氧生物学效应学术会议

作者： Xin Wang,Tao Zhang,Jiang Z Liu,Wei Zhang,chun Shan Gu,chun xu hai~* Department of Toxicology,School of Preventive Medicine,the Fourth Military Medical University,Xi’an, 710032,China

Background and Aim:Over the past decades,type 2 diabetes mellitus(T2DM) has become a serious public health problem in the whole *** of pancreaticβcell function is a key driver and a hallmark in the pathogenesis of *** response to elevated glucose levels,inβcells,the oxidative catabolism of glucose increases,finally leading to insulin secretion,also called glucose-stimulated insulin

关键词： Nrf2 βcell lipotoxicity antioxidant enzyme redox

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光谱学与光谱分析 2008年第3期28卷 700-703页

作者：胡军常耀明高双斌海春旭李金声谢小萍第四军医大学航空航天医学系航空航天卫生与卫生勤务学教研室陕西西安710032 第四军医大学预防医学系营养教研室陕西西安710032 第四军医大学预防医学系毒理教研室陕西西安710032

融合分子生物学技术与原子吸收光谱对血清中元素铜、铁和锌的化学形态进行研究。用60%乙醇低温(4℃)沉淀血清蛋白的方法将血清中的铜,铁,锌分为结合态和非结合态,原子吸收分光光度计分别测定血清中Cu,Fe和Zn三种元素的总量及非结合态含... 详细信息

融合分子生物学技术与原子吸收光谱对血清中元素铜、铁和锌的化学形态进行研究。用60%乙醇低温(4℃)沉淀血清蛋白的方法将血清中的铜,铁,锌分为结合态和非结合态,原子吸收分光光度计分别测定血清中Cu,Fe和Zn三种元素的总量及非结合态含量,通过减差法求出血清中结合态元素含量,从而建立了Cu,Fe和Zn元素这两种化学形态的分离分析方法,并讨论了有关的实验条件。该方法铜、铁和锌的检出限分别为9·84×10-3μg·mL-1,2·76×10-2μg·mL-1,1·06×10-3μg·mL-1,相对标准偏差为0·30%～2·31%,回收率为95·0%～104·0%。该法已应用于SD大鼠血清中Cu,Fe和Zn三种元素不同化学形态的测量。

关键词：原子吸收光谱法(AAS) 微量元素化学形态

复合抗氧化剂对大鼠肝癌阿霉素化疗外周血的保护作用

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中国现代医学杂志 2006年第15期16卷 2290-2293页

作者：秦绪军海春旭何伟梁欣刘瑞解放军第四军医大学毒理学教研室陕西西安710032

目的观察大鼠肝癌模型腹腔阿霉素化疗引起的外周血的变化以及复合抗氧化剂的保护作用。方法采用Walker-256肿瘤细胞株接种大鼠皮下,得到实体瘤,将实体瘤分割成小块植入大鼠肝脏,制成大鼠移植性肝癌模型,将肝癌模型大鼠随机分成3组,分别... 详细信息

目的观察大鼠肝癌模型腹腔阿霉素化疗引起的外周血的变化以及复合抗氧化剂的保护作用。方法采用Walker-256肿瘤细胞株接种大鼠皮下,得到实体瘤,将实体瘤分割成小块植入大鼠肝脏,制成大鼠移植性肝癌模型,将肝癌模型大鼠随机分成3组,分别为模型组、单纯化疗组和抗氧化剂保护组,同时选取经手术但未接种肿瘤的大鼠作为阴性对照组。抗氧化剂保护组每日给予复合抗氧化剂灌胃,单纯化疗组和抗氧化剂保护组大鼠每2天进行1次腹腔阿霉素化疗,剂量为2mg/kg体重,第8周末处死大鼠,取抗凝全血测定外周血各项指标。结果与阴性组和模型组相比较,单纯化疗组的白细胞数(WBC)、淋巴细胞百分比(LYM%)、淋巴细胞数(LYM)、红细胞数(RBC)、红细胞压积(HCT)、血红蛋白(HGB)、平均血小板体积(MPV)显著降低(P<0.05),单核细胞百分比(MON%)、中性粒细胞百分比(GRA%)、单核细胞数(MON)、中性粒细胞数(GRA)、平均红细胞体积(MCV)、红细胞分布活力(RDW)、平均红细胞血红蛋白含量(MCH)、血小板数(PLT)、血小板分布活力(PDW)显著升高,而抗氧化剂保护组与单纯化疗组相比呈现出了明显的拮抗保护作用。结论大鼠肝癌腹腔阿霉素化疗可以造成外周血损伤,引起血象的明显改变,而复合抗氧化剂可以起到有效地保护作用。

关键词：阿霉素外周血副作用腹腔注射抗氧化剂