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Pedosphere 2020年第4期30卷 528-534页

作者： Beata KlIMEK Marcin CHODAK Matgorzata JAZWA Hamed AZArBAD Maria NIKlINSKA Institute of Environmental Sciences Faculty of BiologyJagiellonian UniversityGronostajowa 7Krakow 30-387(Poland) Department of Management and Protection of Environment AGH University of Science and TechnologyMickiewicza 30Krakow 30-059(Poland) Institute of Biology Faculty of Natural Sciences and TechnologyUniversity of OpoleOleska 22Opole 45-052(Poland)

Soil organic matter(som)in boreal forests is an important carbon *** aim of this study was to assess and to detect factors controlling the temperature sensitivity of som *** were collected from Scots pine,Norway spruce,silver birch,and mixed forests(O horizon)in northern Finland,and their basal respiration rates at five different temperatures(from 4 to 28℃)were *** Q10 values,showing the respiration rate changes with a 10℃ increase,were calculated using a Gaussian function and were based on temperature-dependent *** soil physicochemical parameters were measured,and the functional diversity of the soil microbial communities was assessed using the Microresp?*** temperature sensitivity of som decomposition differed under the studied forest *** forests had the highest temperature sensitivity for som decomposition at the low temperature range(0–12℃).Within this temperature range,the Q10 values were positively correlated with the microbial functional diversity index(H’mic)and the soil C-to-P *** suggested that the metabolic abilities of the soil microbial communities and the soil nutrient content were important controls of temperature sensitivity in taiga soils.

关键词： CoO2 evolution global warming microbial functional diversity Microresp^TM Q10 metabolic coefficient

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天燃气负荷预测的建模与应用研究

计算机仿真 2011年第10期28卷 180-183页

作者：代丽娴广西梧州学院计算机科学系广西梧州543002

研究天燃气负荷预测问题,由于天燃气负荷受人口增多用量增大及天气、季节、节假日等因素影响,具有周期性和随机性的变化规律,形成一种非线性特性,传统预测方法无法进行准确的预测,预测精度比较低。为了提高天燃气负荷的预测精度,提出一... 详细信息

研究天燃气负荷预测问题,由于天燃气负荷受人口增多用量增大及天气、季节、节假日等因素影响,具有周期性和随机性的变化规律,形成一种非线性特性,传统预测方法无法进行准确的预测,预测精度比较低。为了提高天燃气负荷的预测精度,提出一种基于rBF神经网络的天燃气负荷预测方法。首先对天燃气负荷历史数据进行预处理,剔掉一些异常的数据,然后将数据输入到rBF神经网络中学习,采用遗传算法对rBF神经网络参数进行优化,从而建立最优的天燃气负荷预测模型。采用某企业的天燃气负荷数据对模型的性能进行验证,实验结果表明,相对于传统预测方法,rBF神经网络提高了天燃气负荷预测精度,是一种较好的天燃气预测方法。

关键词：天燃气负荷预测人工神经网络

long-Term Effects of Alternative residue Management Practices on Soil Water retention in a Wheat-Soybean, Double-Crop System in Eastern Arkansas

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Open Journal of Soil Science 2015年第9期5卷 199-209页

作者： ryan Norman Kristofor r. Brye Edward E. Gbur Pengyin Chen John rupe Department of Crop Soil and Environmental Sciences University of Arkansas Fayetteville USA Agricultural Statistics laboratory University of Arkansas Fayetteville USA Department of Plant Pathology University of Arkansas Fayetteville USA

Soil water retention is a critical aspect of agricultural management, especially in areas such as the lower Mississippi river Alluvial Valley that face potential water shortages in the near future. Previous studies have linked changes in soil water retention characteristics to agricultural management practices, especially as they affect the accumulation of soil organic matter (som). Therefore, the objective of this study was to determine the relationship between soil water potential and gravimetric soil water content in the top 7.5 cm as affected by nitrogen (N) fertilization/residue level (high and low), residue burning (burning and non-burning), tillage (conventional and no-tillage), and irrigation (irrigated and non-irrigated) after 12 complete cropping cycles in a wheat (Triticum aestivum l.)-soybean [Glycine max (l.) Merr.], double-crop production system in the Delta region of eastern Arkansas using soil wetting curves. The soil investigated was a Calloway silt loam (fine silty, mixed, active, thermic Glossaquic Fraglossudalf). The slope characterizing the relationship between the natural logarithm of the soil water potential and the gravimetric soil water content was only affected (P rtilization/residue-level treatment, while the intercept was unaffected by any field treatment. Averaged across tillage, burning, and irrigation, soil water contents under the high-exceeded those under low-N-fertilization/residue-level treatment at the same water potential, with the greatest differences observed at water contents > 0.12 g·g-1. Understanding the ways in which alternative residue management practices affect soil water retention characteristics is an important component of conserving irrigation water resources.

关键词： Water retention Tillage residue Burning

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土壤有机碳和氮分解对温度变化的响应机制

生态学杂志 2008年第9期27卷 1601-1611页

作者：吴建国吕佳佳中国环境科学研究院北京100012

土壤碳和氮分解对温度变化响应过程是气候变化对陆地生态系统碳汇影响的关键。本文针对土壤有机碳和氮分解对温度变化响应机制和假说进行了概括分析。土壤碳和氮分解对温度变化的响应机制主要包括:土壤有机质的稳定性、质量及有效性,微... 详细信息

土壤碳和氮分解对温度变化响应过程是气候变化对陆地生态系统碳汇影响的关键。本文针对土壤有机碳和氮分解对温度变化响应机制和假说进行了概括分析。土壤碳和氮分解对温度变化的响应机制主要包括:土壤有机质的稳定性、质量及有效性,微生物生物量和活性及群落结构或多样性,土壤湿度,以及植被生产力、凋落物和pH等因素的作用。对这些机制还存在很大不确定性,需要考虑土壤有机质组分或微生物属性,同时需要考虑土壤有机质组分与微生物属性间的相互作用,以及土壤碳和氮分解对温度变化短期和长期响应过程的差异。土壤碳和氮分解对温度变化的响应机制的3个假说包括有机质分解质量-温度假说、有机质物理化学过程假说和功能移动假说,这些假说还需要验证和补充完善。

关键词：温度变化土壤碳和氮循环气候变化

青壮年人群中受教育程度、15年危险因素进展以及冠状动脉钙化之间的关系:青年人冠状动脉危险进展研究

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世界核心医学期刊文摘（心脏病学分册） 2006年第7期2卷 1-2页

作者： Daviglus M.l. 罗亮

Context: The inverse association between education and cardiovascular disease is well established, but little is known about the relationship between education and subclinical disease, which is free from medical access and treatment-related influences, or about possible mediating pathways for these relationships. Objective: To examine the association of education with coronary artery calcium(CAC), an indicator of subclinical atherosclerosis, and cardiovascular risk factors, and their changes as potential mediators. Design, Setting, and Participants: A population-based, prospective, observational study(Coronary Artery risk Development in Young Adults[CArDIA]) of 2913 eligible participants(44.9%black; 53.9%women) recruited from 4 metropolitan areas(Birmingham, Ala; Chicago, Ill; Minneapolis, Minn; and Oakland, Calif) in both the baseline(1985-1986, ages 18-30 years) and year 15 examinations(2000-2001, ages 33-45 years). Education(year 15) was classified into less than high school(n=128), high school graduate(n=498), some college(n=902), college graduate(n=764), and more than college(n=621). Main Outcome Measure: Presence of CAC, measured twice by computed tomography(mean total Agatston score >0) at year 15. results: Overall CAC prevalence in this sample was 9.3%. After adjusting for age, race, and sex, the odds ratios(Ors) for having CAC were 4.14(95%confidence interval[CI], 2.33-7.35) for less than high school education, 1.89(95%CI, 1.23-2.91)for high school graduate, 1.47(95%CI, 0.99-2.19) for some college, and 1.24(95%CI, 0.84-1.85) for college graduate compared with those participants with more than a college education(P for trendlso consistent within each of the 4 race-sex groups. Adjustment for baseline systolic blood pressure, smoking, waist circumference, physical activity, and total cholesterol reduced the Ors to 2.61(95%CI, 1.40-4.85) for less than high school, 1.38(95%CI, 0.88-2.17) for high school graduate, 1.17(95%CI, 0.78-1.77) for som

关键词：冠状动脉钙化青壮年人群基线年龄亚临床心血管疾病前瞻性观察总胆固醇水平明尼阿波利斯伊利

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文化多样性语境下的亚太地区活态遗产保护

建筑遗产 2016年第3期 28-39页

作者：吕舟清华大学建筑学院

亚太地区文化的多样性和延续性决定了亚太地区文化遗产的基本特征。这些基本特征在2 0世纪9 0年代以后的国际文化遗产保护运动中得到越来越多的关注,并影响了一些新的文化遗产类型,如文化景观等的出现。在亚太地区文化遗产的各种特征中... 详细信息

亚太地区文化的多样性和延续性决定了亚太地区文化遗产的基本特征。这些基本特征在2 0世纪9 0年代以后的国际文化遗产保护运动中得到越来越多的关注,并影响了一些新的文化遗产类型,如文化景观等的出现。在亚太地区文化遗产的各种特征中,遗产与现实生活,特别是文化生活之间密切的关系,是其最为核心的特征,具有这种特征的遗产被称为活态遗产。对活态遗产的认知是文化遗产保护发展的重要成就,而对活态遗产的保护,使遗产的所有者、传承者和社区在文化遗产保护中具有核心作用。

关键词：文化遗产亚太地区活态遗产社区

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一种基于纹理特征的超声心动图像分割算法

模式识别与人工智能 2005年第4期18卷 474-479页

作者：王勇吕扬生邢占峰周仲兴天津大学生物医学工程系天津300072

以马尔可夫随机过程和梯度小波变换为基础提出了梯度小波纹理模型。由梯度小波纹理模型的参数组成描述图像纹理的特征向量,梯度小波纹理模型利用了马尔可夫随机场图像模型的优点和基于该模型的成熟方法,并且引入了多尺度、多分辨率等特... 详细信息

以马尔可夫随机过程和梯度小波变换为基础提出了梯度小波纹理模型。由梯度小波纹理模型的参数组成描述图像纹理的特征向量,梯度小波纹理模型利用了马尔可夫随机场图像模型的优点和基于该模型的成熟方法,并且引入了多尺度、多分辨率等特性。然后采用Kohonen自组织som(Self-Organizing Feature Map)神经网络对纹理特征向量进行无监督学习,最后对超声心动图像进行纹理分割,取得较满意的分割效果。

关键词：马尔可夫随机场梯度小波 Kohonen自组织神经网络超声心动图像纹理分割

Impact of natural disturbance, forest management and vegetation cover on topsoil biochemical characteristics of Tatra Mts.(Slovakia)

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Journal of Mountain Science 2020年第6期17卷 1294-1309页

作者： Jana GáFrIKOVá Milan ZVAríK Peter HANAJíK Marek SúlOVSKY Ivana VYKOUKOVá Faculty of Natural Sciences Comenius UniversityBratislava84104Slovak Republic Faculty of Mathematics Physics and InformaticsComenius UniversityBratislava84104Slovak Republic Water research Institute Bratislava81249Slovak Republic

Perturbations caused by windstorms usually lead to the harvesting and clearcutting of fallen trees and wood debris,especially in the areas of managed forest *** shifts in soils due to management practices play a crucial role in the restoration and maintaining of key ecosystem *** paper focuses on topsoil chemical properties in relation to vegetation type(trees,shrubs and herbs)evolving at windstorm damaged(in 2004)areas with former Norway spruce(Picea abies)forests in the Tatra ***(Slovakia).We assessed the content of topsoil organic matter fractions(extractives,holocellulose(HC)and lignin(lig)),carbon in microbial biomass(Cmic),soil organic matter(som)and the content of elements N,C,H and *** study plots represent different types of post-windthrow disturbance history/regime:wooden debris extraction(EXT),wooden debris not extracted(NEX),wooden debris extraction followed by wildfire(FIr),affected by the windstorm in 2014 with the subsequent wooden debris extraction(rEX)and unaffected(rEF).Our results revealed significant differences among sites in the content of dichloromethane extractives(EXT *** and FIr),acetone extractives(NEX ***,FIr and rEF),ethanol extractives(FIr ***,NEX and rEF),water extractives(FIr ***,NEX)and Cmic(EXT ***,FIr and rEF).The topsoil of Vaccinium myrtillus and Picea abies showed a higher ratio of C/N,N/lig,and lig/HC compared to rubus idaeus,Avenella flexuosa,Calamagrostis villosa,and larix *** content of N,C,H and S varied between topsoil with shrubs(Vaccinium myrtillus,rubus idaeus)and grasses(Avenella flexuosa,Calamagrostis villosa).A positive correlation between soil organic matter(som)and polar extractives(r=0.81)and a negative correlation between som and HC(r=-0.83)was *** carbon content in microbial biomass(Cmic)is positively correlated with acid soluble lignin(ASl)(r=0.85).We also identified a strong correlation between Klason lignin(Kl)and the lig/HC ratio(r=0.97).

关键词： Windthrow Wildfire Organic matter fractions Vegetation type Norway spruce Topsoil chemical properties

鼓室注射曲安奈德联合盐酸氨溴索治疗分泌性中耳炎的Meta分析

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重庆医学 2013年第27期42卷 3219-3221,3224页

作者：薛莲周建荣重庆医科大学附属第一医院耳鼻咽喉科 400016

目的客观评价鼓室注射曲安奈德联合盐酸氨溴索治疗分泌性中耳炎(som)的疗效和安全性。方法通过检索PubMed、Embase、中国期刊全文数据库、万方、维普数据库,收集关于鼓室注射曲安奈德联合盐酸氨溴索治疗som的相关文献。严格制订纳入和... 详细信息

目的客观评价鼓室注射曲安奈德联合盐酸氨溴索治疗分泌性中耳炎(som)的疗效和安全性。方法通过检索PubMed、Embase、中国期刊全文数据库、万方、维普数据库,收集关于鼓室注射曲安奈德联合盐酸氨溴索治疗som的相关文献。严格制订纳入和排除标准后对相关文献进行筛选,对纳入的文献进行严格的质量评价和数据提取,用revMan5.2软件进行Meta分析。结果 5个随机对照研究(rCT)共615耳纳入研究。在5个对照研究中,治疗组(鼓室注射曲安奈德+盐酸氨溴索)的疗效和对照组(鼓室注射地塞米松+盐酸氨溴索)比较:Or(95%CI)为4.25(2.71,6.66),差异有统计学意义(Pr(95%CI)1.67(0.61,4.60),差异有统计学意义(P=0.32)及Or(95%CI)0.16(0.03,0.94),差异有统计学意义(P=0.04)。结论在som的治疗中,鼓室注射曲安奈德联合盐酸氨溴索的疗效优于地塞米松联合盐酸氨溴索;鼓室注射曲安奈德联合盐酸氨溴索的疗效与鼓膜置管相当,但并发症发生率低于鼓膜置管。因此,鼓室注射曲安奈德联合盐酸氨溴索治疗som值得临床推广。

关键词：中耳炎伴渗出液 Meta分析曲安奈德盐酸氨溴索

不同种类生长抑素类似物对肝细胞肝癌作用差异的实验研究

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四川大学学报（医学版） 2017年第4期48卷 549-555页

作者：吕修和王春晖谢艳四川大学华西医院消化内科成都610041

目的观察som230、奥曲肽、兰瑞肽对体内外Bel-7402肝癌细胞的作用,分析其疗效差异及可能的机制。方法采用不同浓度(1×10^(-10)~1×10^(-5) mol/l)som230、奥曲肽和兰瑞肽处理Bel-7402肝癌细胞,作用24h、48h和72h时,采用CCK8法检测细胞... 详细信息

目的观察som230、奥曲肽、兰瑞肽对体内外Bel-7402肝癌细胞的作用,分析其疗效差异及可能的机制。方法采用不同浓度(1×10^(-10)~1×10^(-5) mol/l)som230、奥曲肽和兰瑞肽处理Bel-7402肝癌细胞,作用24h、48h和72h时,采用CCK8法检测细胞增殖;采用1×10^(-5) mol/l浓度的3种药物处理细胞24h、48h和72h,AnnexinⅤ-FITC/PI双染法检测细胞凋亡;荧光定量PCr检测药物作用前后细胞生长抑素受体(SSTr)表达的变化。建立Bel-7402细胞裸鼠移植瘤模型,干预组分别予som230、奥曲肽、兰瑞肽100μg/(kg·d),对照组予同体积生理盐水,连续用药6周(皮下注射),荧光定量PCr及Western blot检测肿瘤组织中SSTr的基因及蛋白表达变化。结果 3种药物均可抑制Bel-7402细胞的增殖,但均无法促进其凋亡。在体外水平,SSTr1、SSTr4在各组间的表达量均不随时间发生变化;与对照组比较,SSTr2在干预组中的表达量均表现为随干预时间延长而减少(Pr5在干预组中的表达量均表现为随干预时间延长先增加后减少(Pr1基因在som230组表达量较奥曲肽、兰瑞肽及对照组增加;SSTr2基因在3个干预组中的表达量较对照组均增加;SSTr5基因在som230组及兰瑞肽组中的表达量较奥曲肽组及对照组增加;上述差异均具统计学意义(Prn blot从蛋白水平验证了上述结果。结论在一定浓度范围内,采用针对SSTr2和SSTr5具有高亲合力的生长抑素类似物(SSTA)长期治疗可抑制肝癌细胞的生长。

关键词：生长抑素肝肿瘤 Bel-7402细胞移植瘤