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北京山区典型植被土壤水分对次降雨的响应

生态学报 2024年第6期44卷 2561-2571页

作者：王坤悦李旭红余新晓贾国栋张益党毅北京林业大学国家林草局水土保持重点实验室北京100083

为了揭示北京山区不同植被类型土壤水分对不同强度降雨的响应过程,选取北京山区内侧柏、荆条灌丛、荒草地为研究对象,基于2022年6—1.月降雨和土壤水分的连续观测数据,分析土壤水分对不同降雨事件的响应特征。结果表明:(1.观测期内研究... 详细信息

为了揭示北京山区不同植被类型土壤水分对不同强度降雨的响应过程,选取北京山区内侧柏、荆条灌丛、荒草地为研究对象,基于2022年6—1.月降雨和土壤水分的连续观测数据,分析土壤水分对不同降雨事件的响应特征。结果表明:(1.观测期内研究区降雨事件主要由小雨构成,小雨事件的总降雨量占总降雨量的1..78%,小雨事件对土壤水分的响应深度可达到40—60 cm土层;中雨、大雨、暴雨事件的总降雨量占总降雨量的85.52%,中雨、大雨、暴雨事件对土壤水分的响应深度均可达到60—80 cm土层;大降雨事件对土壤水分的补给作用更明显,降雨量越大,降雨能补给的土层深度越深,土壤水分补给效果越好。(2)三种植被平均土壤水分补给速率大小依次为荒草地>侧柏>荆条灌丛,说明降雨对荒草地的补给效果最好;土层活跃程度对植被土壤水分有影响,土层越活跃,土壤水分波动越大,三种植被平均土壤水分变异系数大小依次为荒草地>荆条灌丛>侧柏,而三种植被平均土壤储水量大小则依次为侧柏>荒草地>荆条灌丛,说明侧柏的土壤水分最为稳定。(3)荒草地、荆条灌丛剖面上各层土壤水分逐渐减少,侧柏则增加,说明土壤水分剖面分布受植被类型影响;侧柏、荆条灌丛、荒草地平均最大补给速率均发生在20—40 cm土层,说明降雨对浅层土壤水分的补给最为明显,对0—40 cm土层土壤水分的补给效果要更好。研究成果进一步解释了北京山区生态系统水分运动规律,为易干旱生态脆弱地带生态环境建设提供依据。

关键词：北京山区植被类型土壤水分降雨

Trends in Temperature and Precipitation Extremes over Circum-Bohai-Sea Region,China

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Chinese Geographical Science 2012年第1期22卷 75-87页

作者： JIANG Dejuan li Zhi {1. Qiuxian Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China College of Resources and Environment Northwest Agriculture and Forestry University Yangling 712100 China School of Geography and Planning Ludong University Yantai 264025 China

Trends in temperature and precipitation extremes from 1.61.to 2008 have been investigated over Circum-Bohai-Sea region, China using daily temperature and precipitation data of 63 meteorological stations. The re- suits show that at most stations, there is a significant increase in the annual frequency of warm days and warm nights, as well as a significant decrease in the annual frequency of cold days, cold nights, frost days, and annual diurnal tem- perature range （DTR）. Their regional averaged changes are 2.06 d/1.0yr, 3.95 d/1.yr, -1.88 d/1.yr, -4.27 d/1.yr, -4.21.d/1.yr and -0.20℃/1.yr, respectively. Seasonal changes display similar patterns to the annual results, but there is a large seasonal difference. A significant warming trend is detected at both annual and seasonal scales, which is more contributed by changes of indices defined by daily minimum temperature than those defined by daily maximum tem- perature. For precipitation indices, the regional annual extreme precipitation displays a weak decrease in terms of magnitude and frequency, i.e. extreme precipitation days （RD95p）, intensity （RINTEN）, proportion （RPROP） and maximum consecutive wet days （CWD）, but a slight increase in the maximum consecutive dry days （CDD）, which are consistent with changes of annual total precipitation （PRCPTOT）. Seasonally, PRCPTOT and RD95p both exhibit an increase in spring and a decrease in other seasons with the largest decrease in summer, but generally not significant. In summary, this study shows a pronounced warming tendency at the less rainy period over Circum-Bohai-Sea region, which may affect regional economic development and ecological protection to some extent.

关键词： temperature precipitation climate extreme trend analysis Circum-Bohai-Sea region

Population dynamics of Acartia pacifica (Copepoda:Calanoida):the importance of benthic-pelagic coupling

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Acta Oceanologica Sinica 2006年第6期25卷 88-98页

作者： JIANG Xiaodong wang Guizhong {1. Shaojing Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of China Shanghai 200136 China department of Oceanography State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

The seasonal occurrence of Acartia pacifica （ Copepoda： Calanoida） and their resting eggs in the sediment of Xiamen Bay were documented between October 2002 and September 2003. The numher of viable eggs in the sediment increased from January to May with the increase in the numher of planktonic females. When the population ofA. pacifica disappeared from the water cohinm, the number of eggs in the sediment began to decrease and reached a low value due to lack of input. The peak of nauplii abundance occurred when the hatching potential of eggs from the sediment was high under the natural environment from February to June. The hatching of resting eggs of A. pacifica was essentially temperature-dependent after suspension, while photoperied regimes had no significant effect on the hatching. The mean density of subitaneeus eggs was 1. 1.2 0 g/cm^3 with a standard deviation （SD） of 0. 000 2 g/cm^3. The mean density of diapause eggs was 1. 1.1.2 g/cm^3 with a SD of 0.000 1.g/cm^3. The sinking rates of subitaneons eggs ranged from 1..55 to 26.1. m/d, while those of diapause eggs ranged from 30.29 to 31.28 m/d. The comparison of the egg deposition time and egg hatching time suggested that in most cases virtually all subitaneous eggs of A. pacifica would settle to the bottom before their hatching even though the eggs have high potential to hatch. The evidence was provided that the seasonal dynamics of A. pacifica is accompanied by benthic-pelagic coupling.

关键词： population dynamics benthic - pelagic coupling Acartia pacifica

耳内镜下中耳胆脂瘤术中应用β-磷酸三钙填塞乳突的治疗效果

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临床耳鼻咽喉头颈外科杂志 2024年第7期38卷 651-655页

作者：张燕灵李巍王浩赵泽祺肖朝球丁锐陈白徐州医科大学第一临床医学院江苏徐州221004 徐州医科大学附属医院耳鼻咽喉头颈外科

目的:探讨耳内镜术中使用β-磷酸三钙填塞乳突术腔的治疗效果。方法:将2021.9月至2022年3月收治的中耳胆脂瘤患者60例纳入研究。观察组30例,术中填塞β-磷酸三钙;对照组30例,术中填塞自体组织。2组患者术前、术后行纯音听阈测听,记录50... 详细信息

目的:探讨耳内镜术中使用β-磷酸三钙填塞乳突术腔的治疗效果。方法:将2021.9月至2022年3月收治的中耳胆脂瘤患者60例纳入研究。观察组30例,术中填塞β-磷酸三钙;对照组30例,术中填塞自体组织。2组患者术前、术后行纯音听阈测听,记录500、1.00、2000、4000 Hz气导阈值;测量术中乳突填塞完成后及术后外耳道口内1.cm处横截面积。比较2组患者术后干耳时间、听力改变情况、乳突术腔愈合情况差异。结果:观察组患者术后干耳时间为4~1.周,平均(9.4±2.7)周;对照组患者术后干耳时间为4~26周,平均(1..0±5.7)周;2组干耳时间差异有统计学意义(P1.~27 dB,平均(6.4±1..7)dB;对照组气导听阈较术前改变值为-9~1. dB,平均(4.7±7.1.dB;2组听力改变差异无统计学意义(P>0.05)。观察组术后外耳道口内1.cm处面积较术中改变值为-5.9~8.2 mm^(2),平均为(-0.6±2.6)mm^(2);对照组术后外耳道口内1.cm处面积较术中改变值为-5.5~5.2 mm^(2),平均为(-0.4±2.3)mm^(2);2组术腔改变差异无统计学意义(P>0.05)。结论:内镜中耳胆脂瘤术中应用β-磷酸三钙填塞乳突术腔对患者听力无不良影响,可缩短术后干耳时间,患者术后愈合良好,值得推广。

关键词：内镜中耳胆脂瘤乳突 β-磷酸三钙

保残修补对退行性肩袖全层撕裂术后肩袖愈合及肩关节功能的影响研究

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中国修复重建外科杂志 2024年第2期38卷 145-150页

作者：李行星窦强兵周亮郑权孙良业任龙王启伟安徽医科大学附属六安医院骨科安徽六安237001 霍邱县第二人民医院骨科安徽霍邱237400

目的探讨保留足印区残端的肩袖修补术对退行性肩袖全层撕裂术后肩袖愈合以及肩关节功能的影响。方法回顾性分析2.1.年4月—2022年5月1.2例接受关节镜下肩袖修补术的退行性肩袖全层撕裂患者临床资料。男76例,女76例;年龄24~78岁,平均55.... 详细信息

目的探讨保留足印区残端的肩袖修补术对退行性肩袖全层撕裂术后肩袖愈合以及肩关节功能的影响。方法回顾性分析2.1.年4月—2022年5月1.2例接受关节镜下肩袖修补术的退行性肩袖全层撕裂患者临床资料。男76例,女76例;年龄24~78岁,平均55.4岁。术后6个月复查MRI,根据Sugaya分型评估肩袖愈合情况。对年龄(≥60岁/3个月)、保残修补(是/否)、缝线桥技术固定(是/否)、打结时肩关节外展角度(2周)、术后开始主动锻炼时间(≤3个月/>3个月)进行单因素分析,初步筛选肩袖愈合的影响因素;进一步采用logistic回归进行多因素分析,筛选危险因素。以是否使用保残修补作为分组条件,使用倾向性评分匹配平衡两组数据,对术后6、1.个月肩关节功能美国肩肘外科协会评分(ASES)、Constant-Murley评分以及术后6个月肩袖愈合进行组间比较。结果术后1.2例患者均获随访,随访时间1.~33个月,平均23.8个月。术后25~31.复查MRI示肩袖愈合1.1.、未愈合31.。单因素分析示病程、保残修补、打结时肩关节外展角度及术后开始主动锻炼时间是修补术后肩袖愈合的影响因素(P1.患者。保残组术后6个月肩袖愈合率、ASES评分及Constant-Murley评分均优于非保残组,差异有统计学意义(P1.个月ASES评分及ConstantMurley评分差异无统计学意义(P>0.05)。结论对于退行性全层肩袖撕裂患者,与不保留残端修补相比,保留足印区残端的肩袖修补术可以缩短肩袖愈合时间,肩关节功能恢复更快,但术后1.肩关节功能无明显差异。

关键词：退行性肩袖全层撕裂保留残端肩袖修补

基于烟酰胺磷酸核糖转移酶(NAMPT)探讨红景天苷在非酒精性脂肪性肝病小鼠模型中的保护作用

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临床肝胆病杂志 2024年第1期40卷 64-69页

作者：李荣军徐春霞张庭张志红王缕泸州市中医医院脾胃病肝病科四川泸州646000 西南医科大学附属医院全科医学科四川泸州646000

目的研究红景天苷对非酒精性脂肪性肝病(NAFLD)的保护作用,并探讨其作用机制。方法将24只雄性KM小鼠随机分为正常组、高脂饮食(HFD)组、HFD+空白对照组、HFD+红景天苷组,每组6只,正常组小鼠予以普通饲料喂养,其余各组高脂饮食,造模1.周... 详细信息

目的研究红景天苷对非酒精性脂肪性肝病(NAFLD)的保护作用,并探讨其作用机制。方法将24只雄性KM小鼠随机分为正常组、高脂饮食(HFD)组、HFD+空白对照组、HFD+红景天苷组,每组6只,正常组小鼠予以普通饲料喂养,其余各组高脂饮食,造模1.周开始给予1.0 mg·kg^(-1.·d^(-1.红景天苷灌胃给药,22周末取材。酶联免疫法测定血清ALT、AST、TG、TC、HDL-C、LDL-C等相关生化指标;HE染色和NAFLD活动评分(NAS)观察小鼠肝组织病理。Western Blot检测肝组织内烟酰胺磷酸核糖转移酶(NAMPT)、Sirt1.AMPKα、SREBP1.表达变化。多组间比较采用单因素方差分析,进一步两两比较采用LSD-t检验。结果与正常组比较,HFD组小鼠肝组织存在广泛较大的脂肪滴,脂肪变性明显,NAS评分升高(P1.,外周血AST、ALT、TG、TC、LDL-C的含量明显增高(P值均1.表达降低(P值均1.表达增加(P1.。而HFD+红景天苷组较HFD组、HFD+空白对照组肝组织空泡状脂滴分布、小叶内炎症减少,肝细胞气球样变减轻,NAS评分下降(P1.,外周血AST、ALT、TG、LDL-C的含量明显降低(P值均1.表达增加(P值均1.表达减少(P1.。结论红景天苷能明显改善高脂饮食诱导小鼠NAFLD的病理状态,并通过增加NAMPT、Sirt1.AMPKα的表达,减少SERBP1.表达,发挥其对NAFLD的保护作用。

关键词：烟酰胺磷酸核糖基转移酶红景天苷非酒精性脂肪性肝病小鼠

维普期刊数据库博看期刊

An Autocatalytic Synthetic Route to[5]Ferrocenophane and its Mechanism Investigation

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An Autocatalytic Synthetic Route to[5]Ferrocenophane and its...

Optimal decision-making model of spatial sampling for survey of China's land with remotely sensed data

中国化学会第十届全国有机合成化学学术研讨会

作者： Jian-chun wang,Zhen-min Chen,Zhong-feng {1.,Xiao-fang Wu,Xiao-lan Jiao,Ke-xin Zhang {1. of chemistry,Capital Normal university,1.0048,Beijing,P.R.China

An easy and reliable synthetic route to[5]ferrocenophane was found unexpectedly and *** novel[5]ferrocenophanes were synthesized from 1.(1.Chloro-2-formylvinyl)- 1.-(1.chlorovinyl)-ferrocene 1.with primary,secondary and tertiary *** ferrocenophanes were characterised by elemental analysis,IR,H NMR and *** single crystals of three [5]ferrocenophanes were obtained and the crystal structures were determined by X-ray diffraction. Meanwhile in situ H NMR was employed to study the reaction mechanism of the compound {1. *** results show that the reaction are related with alcohol acidity and steric *** stronger is the alcohol acidity,the faster is the reaction,and the speed of primary alcohol with the compound 1.is the fastest,then followed by the secondary alcohol,the reaction of tertiary alcohol with the compound 1.can not happen.

关键词：

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Science China Earth Sciences 2005年第6期48卷 752-764页

作者： li lianfa wang Jinfeng liU Jiyuan Institute of Geographic Sciences&Natural Resources Research Chinese Academy of SciencesBeijing 100101China department of Intel{1.gence Science Peking UniversityBeijing 100087China

In the remote sensing survey of the country land, cost and accuracy are a pair of conflicts, for which spatial sampling is a preferable solution with the aim of an optimal balance between economic input and accuracy of results, or in other words, acquirement of higher ac-curacy at less cost. Counter to drawbacks of previous application models, e.g. lack of compre-hensive and quantitative-comparison, the optimal decision-making model of spatial sampling is proposed. This model first acquires the possible accuracy-cost diagrams of multiple schemes through initial spatial exploration, then regresses them and standardizes them into a unified ref-erence frame, and finally produces the relatively optimal sampling scheme by using the discrete decision-making function (built by this paper) and comparing them in combination with the dia-grams. According to the test result in the survey of the arable land using remotely sensed data, the Sandwich model, while applied in the survey of the thin-feature and cultivated land areas with aerial photos, can better realize the goal of the best balance between investment and accuracy. With this case and other cases, it is shown that the optimal decision-making model of spatial sampling is a good choice in the survey of the farm areas using remote sensing, with its distin-guished benefit of higher precision at less cost or vice versa. In order to extensively apply the model in the surveys of natural resources, including arable farm areas, this paper proposes the prototype of development using the component technology, that could considerably improve the analysis efficiency by insetting program components within the software environment of GIS and RS.

关键词： survey of countrywide land with RS data spatial sampling optimal decision-making model of spatial sampling.

2型糖尿病患者正常水平血清肌酐与糖尿病肾病的前瞻性队列研究

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中华内分泌代谢杂志 2024年第5期40卷 380-385页

作者：程旦汤芳丽汪文俊刘欢欢李洮俊楼青青海南医学院国际护理学院海口571199 海南医学院第一附属医院 (海南省)代谢性疾病临床医学研究中心海口570102 海南省人民医院内分泌科海口570311 中国台湾李氏联合诊所内分泌科中国台湾屏东900

目的探讨正常水平血清肌酐(serum creatinine, Scr)与2型糖尿病(type 2 diabetes mellitus, T2DM)患者糖尿病肾病(diabetic kidney disease, DKD)的关系。方法本研究为前瞻性队列研究, 选取200{1.1.至{1.年1.月31.在中国台湾李氏... 详细信息

目的探讨正常水平血清肌酐(serum creatinine, Scr)与2型糖尿病(type 2 diabetes mellitus, T2DM)患者糖尿病肾病(diabetic kidney disease, DKD)的关系。方法本研究为前瞻性队列研究, 选取200{1.1.至{1.年1.月31.在中国台湾李氏联合诊所6个中心定期随访的T2DM患者作为研究对象。基线时患者无DKD, 收集患者的一般资料、实验室检查指标。根据患者随访时间内是否发生DKD将患者分为DKD组和无DKD组(nondiabetic kidney disease, NDKD)。暴露因素是Scr(μmol/L)值, 并作为分类变量, 根据Scr四分位数分为4组:Q1.(Scr1.μmol/L)、Q3组(68.51.μmol/L≤Scr1.)年随访时间后, 共有966例患者发生了DKD, 1.236例患者未发生DKD。与NDKD组相比, DKD组年龄更大, 糖尿病病程更长, 体重指数、收缩压、舒张压、低密度脂蛋白胆固醇、Scr、尿蛋白/肌酐比值更高(均P1.为对照, 在校正混杂因素后, Q2、Q3、Q4组发生DKD结局的风险分别为1.394、1.688、2.821.(均P1.Q2、Q3组, 差异有统计学意义(均P74.27 μmol/L时, 更应高度关注DKD发生的可能性。

关键词：糖尿病肾病糖尿病 2型血清肌酐