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起脚方式与趾长类型相关性初探
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作者 田亚杰 胡书良 +3 位作者 刘晋 林敏 叶方坚 王明直 《中国司法鉴定》 2017年第5期63-67,共5页
目的探索起脚方式与拇趾二趾长度比较关系的相关性。方法对236名20~40岁左右的男性无腿部疾病的健康警察正常行走时的起脚方式进行分析,测量出其拇趾二趾长度关系,利用贝叶斯概率计算出在每种行走方式中拇趾二趾长度关系概率。结果当起... 目的探索起脚方式与拇趾二趾长度比较关系的相关性。方法对236名20~40岁左右的男性无腿部疾病的健康警察正常行走时的起脚方式进行分析,测量出其拇趾二趾长度关系,利用贝叶斯概率计算出在每种行走方式中拇趾二趾长度关系概率。结果当起脚方式为偏内起脚时,拇趾长概率为94.4%;当起脚方式为正起脚时,拇趾二趾同长概率为52.7%;当起脚方式为偏外起脚时,二趾长概率为86.7%。结论起脚方式与趾长类型相互联系,相互影响,相互制约。 展开更多
关键词 脚印 起脚方式 长类型
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在Visual C++中利用MFC类库访问数据库中的长二进制类型数据 被引量:3
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作者 王井阳 张晓明 +1 位作者 阮冬茹 白云飞 《计算机应用研究》 CSCD 北大核心 2003年第10期119-121,共3页
数据库中的长二进制类型(如SQLServer的Image,Oracle的LONGRAW等)字段可以存储如图形、声音文件或带格式的大文本文件等大对象数据,并且这些数据是以二进制流形式存放。介绍了VC通过MFCODBC类连接到数据库并利用MFC类库的CLongBinary类... 数据库中的长二进制类型(如SQLServer的Image,Oracle的LONGRAW等)字段可以存储如图形、声音文件或带格式的大文本文件等大对象数据,并且这些数据是以二进制流形式存放。介绍了VC通过MFCODBC类连接到数据库并利用MFC类库的CLongBinary类和CFile类访问长二进制类型数据的一种简单有效方法,阐明其工作原理和特点,并以操作SQLServer数据库中的Image类型数据为例来进行说明。 展开更多
关键词 二进制类型数据 MFC CFile类 MFC ODBC类 Visual C++
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孩子心中反感的家长类型
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《科学生活》 2009年第2期46-47,共2页
目前家庭教育和亲子关系让人担忧,过去常被人视为最亲密的亲子关系正在出现令人震惊的裂痕。每个父母都希望子女健康幸福、快乐成长,然而家长的拳拳爱心为何换来孩子们的极度反感?这其中的误区到底在哪里?
关键词 亲子关系 父母 反感 诊断 学习成绩 青春期 长类型 中学生 专家分析
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白云鄂博矿床成因——矿体内霓长岩化成矿作用与赋矿白云岩的联系 被引量:21
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作者 王凯怡 张继恩 +2 位作者 方爱民 董策 胡辅佑 《岩石学报》 SCIE EI CAS CSCD 北大核心 2018年第3期785-798,共14页
通过对组成赋矿白云岩的白云石矿物系统的显微结构和化学成分的研究表明,赋矿白云岩是碳酸岩质次火山岩,因此白云鄂博矿床是与火成碳酸岩有关的矿床。赋矿白云岩属于镁质碳酸岩(MgO>FeO+MnO)和铁质碳酸岩(MgO<FeO+MnO)系列,FeO、... 通过对组成赋矿白云岩的白云石矿物系统的显微结构和化学成分的研究表明,赋矿白云岩是碳酸岩质次火山岩,因此白云鄂博矿床是与火成碳酸岩有关的矿床。赋矿白云岩属于镁质碳酸岩(MgO>FeO+MnO)和铁质碳酸岩(MgO<FeO+MnO)系列,FeO、MnO和SrO含量高,这与FeO、MnO和SrO含量很低的沉积碳酸岩完全不同。赋矿白云岩的这一特点还表明它来自经历过分异结晶后的白云质碳酸岩浆而不是初始白云质碳酸岩浆。赋矿白云岩复杂的矿物组合表明,其母岩浆是富含F、Cl、P和S这些挥发分以及REE,Na、K和Fe这些元素的。在碳酸岩浆上升和侵位的过程中由于温度压力的降低,碳酸岩浆释放的含上述组分的流体会向上部地壳集中并对其接触的围岩进行交代,这就形成了矿体内呈不对称带状分布的霓长岩化矿石带。在大量的萤石和稀土氟碳酸盐矿物形成以后(其对应于萤石-稀土条带状矿石),流体的成分仍相对富钠和CO_2,钠可以和围岩中的硅结合形成钠辉石,流体较高的比值,有利于稀土的富集,此时形成的钠辉石型矿石的稀土含量是相当高的,仅次于条带状矿石。随着流体继续迁移和交代,流体中CO_2浓度下降而H_2O含量增加,温度也有所下降,但是流体中的钠依然活跃,所以出现了含有结构水的钠闪石,形成了钠闪石型矿石。流体中H_2O的增加,比值的下降,不利于稀土的大量富集,因此,钠闪石型矿石的稀土含量明显低于钠辉石型矿石。这说明,从碳酸岩浆中外逸的流体,在迁移交代围岩的过程中其成分、温度和氧逸度都是有变化的。从初期富CO_2,温度和氧逸度较高,到后期富H_2O,温度和氧逸度都有所降低。不同矿石类型的形成与这种变化有直接的关系。不同矿石类型中的磁铁矿的生成方式虽然不同于白云岩中的磁铁矿,但前者的氧同位素继承了后者的特点,表明了它们的亲缘关系和成因上的联系。稀土分布型式表明,不同矿石类型的稀土分布型式与赋矿白云岩的大体一致,有明显的LREE富集和明显的HREE亏损,且总稀土含量越高,轻重稀土分离程度越高。但是,不同矿石类型在轻稀土含量上有一定程度的差别,表明在霓长岩化过程中轻稀土活动性更强。总之,氟、钠和铁的交代作用在主东矿最强,稀土、铌和铁资源也最为富集,这里的白云岩厚度也最大,表明白云鄂博矿的霓长岩化成矿作用与赋矿白云岩衍生的流体的大量聚集以及流体对围岩广泛强烈的交代作用直接相关。 展开更多
关键词 白云鄂博矿床 赋矿白云质碳酸岩 岩化矿石类型 白云鄂博群
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县南沟流域坡长尺度效应的ANUDEM研究 被引量:2
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作者 樊宇 郭伟玲 《金属矿山》 CAS 北大核心 2017年第10期47-51,共5页
坡长是区域水土保持定量评价研究中重要的地形因子之一,以黄土高原地区县南沟流域为研究区,通过ANUDEM软件基于县南沟流域1∶1万比例尺数字地形图,建立5~100 m分辨率的DEM数据,利用LS_TOOL工具提取其上的坡长表面,分析坡长随分辨率变化... 坡长是区域水土保持定量评价研究中重要的地形因子之一,以黄土高原地区县南沟流域为研究区,通过ANUDEM软件基于县南沟流域1∶1万比例尺数字地形图,建立5~100 m分辨率的DEM数据,利用LS_TOOL工具提取其上的坡长表面,分析坡长随分辨率变化的规律。研究表明:随着DEM分辨率的降低,地形特征点的坡长值变化表现出一定的规律性;不同坡长分级区的坡长均值变化呈现出差异性,面积比率在100 m以内的坡长呈下降趋势,其余坡长类型区均呈增加趋势;流域坡长均值随分辨率的变粗整体发生扩张,短坡长逐渐减少,长坡长范围扩大,坡长均值随分辨率变化呈线性递增。 展开更多
关键词 DEM分辨率 地形特征点 长类型
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ODBC技术在长数据存取中的应用
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作者 张军良 邴文丽 《无线电通信技术》 2001年第1期35-38,共4页
主要介绍了应用ODBC技术进行数据库开发的基本方法,并结合ORACLE数据库和VC++讨论了长数据类型存储的关键技术问题。
关键词 开放数据库互连 数据类型 SQL语言 数据库 ORACLE VC
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Evolution of Main Characteristics of the Registered Cotton Cultivars in National Cotton Regional Trials in Yangtze River Valley 被引量:1
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作者 许乃银 李健 《Agricultural Science & Technology》 CAS 2014年第6期964-969,共6页
[Objective] The aim of this study was to characterize the national regis- tered varieties selected from cotton regional trials in Yangtze River Valley (YaRV) in recent years. [Method] Cotton cultivar classification ... [Objective] The aim of this study was to characterize the national regis- tered varieties selected from cotton regional trials in Yangtze River Valley (YaRV) in recent years. [Method] Cotton cultivar classification and comprehensive evaluation index were set up based on national cotton registration standard. GGE biplot method was adopted to analyze the correlation of major breeding target characters of 53 national registered cotton varieties in cotton regional trials in YaRV during 1981-2012. According to the shift of check cultivars in cotton regional trials in the past, the cotton regional trial practice since 1981 was divided into five periods. The dynamic of cultivar type's proportion and the evaluation index scores was analyzed across the five periods. [Result] There existed intricate interrelationship among cotton breeding target traits, which constrained it necessary to construct indices for com- prehensive evaluation of cotton varieties. The dynamic of cultivar types in the five periods indicated that type II varieties emerged since Simian 3 period and then its proportion decreased gradually; type Ⅲ varieties maintained a certain proportion in each period and kept on the rise overall; type Ⅳvarieties occupied the majority pro- portion of registered cultivars before 1993, but a minor proportion since Simian 3 period. On the other side, the change trend of the evaluation index demonstrated that the varieties registered before 2003 did not pass the qualified line at present. The peak scores appeared in the varieties registered during 2004-2008. The scores of the varieties registered after 2009 were only slightly over the qualified line. [Conclusion] More attention should be paid to the improvement and evaluation of micronaire, so as to guide the simultaneous development of high yielding and fiber quality in cotton breeding and registration procedure in YaRV. 展开更多
关键词 Cotton (Gossypium hirsutum L.) GGE biplot Variety type classification The Yangtze River Valley (YaRV)
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对PB访问数据库中大对象数据方法的研究 被引量:4
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作者 李劲 《微计算机信息》 北大核心 2006年第07X期236-238,共3页
为了快速高效地处理数据库中大对象数据,本文介绍了用PowerBuilder开发数据库应用系统时处理大对象数据的三种方法,并对数据库存储大对象数据的原理进行了分析。实践证明,在Oracle数据库中导入和读取大对象数据的实现过程是最可靠、最... 为了快速高效地处理数据库中大对象数据,本文介绍了用PowerBuilder开发数据库应用系统时处理大对象数据的三种方法,并对数据库存储大对象数据的原理进行了分析。实践证明,在Oracle数据库中导入和读取大对象数据的实现过程是最可靠、最安全、最有效的一种方法。 展开更多
关键词 大对象数据 二进制数据类型 PB 数据库
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Annoyance-type speech emotion detection in working environment
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作者 王青云 赵力 +1 位作者 梁瑞宇 张潇丹 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期366-371,共6页
In order to recognize people's annoyance emotions in the working environment and evaluate emotional well- being, emotional speech in a work environment is induced to obtain adequate samples of emotional speech, and a... In order to recognize people's annoyance emotions in the working environment and evaluate emotional well- being, emotional speech in a work environment is induced to obtain adequate samples of emotional speech, and a Mandarin database with two thousands samples is built. In searching for annoyance-type emotion features, the prosodic feature and the voice quality feature parameters of the emotional statements are extracted first. Then an improved back propagation (BP) neural network based on the shuffled frog leaping algorithm (SFLA) is proposed to recognize the emotion. The recognition capability of the BP, radical basis function (RBF) and the SFLA neural networks are compared experimentally. The results show that the recognition ratio of the SFLA neural network is 4. 7% better than that of the BP neural network and 4. 3% better than that of the RBF neural network. The experimental results demonstrate that the random initial data trained by the SFLA can optimize the connection weights and thresholds of the neural network, speed up the convergence and improve the recognition rate. 展开更多
关键词 speech emotion detection annoyance type sentence length shuffled frog leaping algorithm
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何止是金钱和高科技
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作者 赵家映 《电影评介》 2003年第5期52-52,共1页
D 电影阵地的厮杀争夺愈演愈烈,我们的最大对手当然是好莱坞,美国人赚足了银子,又把美国式的“英雄主义”和价值观念灌输过来,无论是为了国产电影生存还是民族意识培育,都不可等闲视之。可是一些人至今对好莱坞片子充满鄙夷,很有些唯我... D 电影阵地的厮杀争夺愈演愈烈,我们的最大对手当然是好莱坞,美国人赚足了银子,又把美国式的“英雄主义”和价值观念灌输过来,无论是为了国产电影生存还是民族意识培育,都不可等闲视之。可是一些人至今对好莱坞片子充满鄙夷,很有些唯我独尊,好像只有我们的电影才有思想深度有艺术品位,他们仰仗的不过是雄厚的资本和高科技电脑制作——每有比拼,便祭出这件护身宝器。这个观念极有害,无论是口头说说还是骨子里就这样认定——你可以咬定美国人使的是左道旁门,但你抵挡不住他们攻城掠地,你可以拒绝WTO,让银幕上熙来攘往全是得到真传的自家弟子,可如今不要钱也没人来看花拳绣腿,何况要钱,市场无情,岂不郁闷? 展开更多
关键词 好莱坞 意识培育 电脑制作 英雄主义 艺术品位 国产电影 高科技 长类型 价值观念 思想深度
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Simultaneous Approximation by Baskakov-Durrmeyer Operator
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作者 齐秋兰 郭顺生 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期38-45,共8页
In this paper, we investigate the degree of approximation by Baskakov_Durrmeyer operator for functions which derivatives have only discontinuity points of the first kind on [0,∞) with exponential growth.
关键词 OPERATORS simultaneous approximation moduli of smoothness
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Spatial distribution and abundance of small fishes in Xiaosihai Lake,a shallow lake along the Changjiang (Yangtze) River, China 被引量:5
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作者 李为 张堂林 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期470-477,共8页
Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was d... Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was divided into three major habitats: Myriophyllum spicaturn habitat (MS habitat), Trapa bispinosa habitat (TB habitat), and non-vegetation habitat (NV habitat). A modified pop-net was used for quantitative sampling of small fishes in the three habitats, and the Zippin's removal method was used for estimating densities of the small fishes. A total of 13 species belonging to 5 families were collected, with 11 species in MS habitat, 7 species in TB habitat, and 5 species in NV habitat. Habitat type had significant effect on the spatial distribution of small fishes. The Shannon-Wiener diversity index in the MS, TB and NV habitats were 1.28, 0.56 and 0.54, respectively. The total density and biomass of small fishes were significantly higher in the MS habitat (13.68 ind/m^2 and 4.44 g/m^2) than in the TB habitat (1.41 ind/m^2 and 0.54 g/m^2) and the NV habitat (1.08 ind/m^2 and 0.40 g/m^2), and were not significantly different between the TB habitat and the NV habitat. Water depth had no significant effect on spatial distribution of the small fishes. It was suggested that vegetation type played an important role in habitat selectivity of small fishes, and the presence of submersed vegetation should be of significance in the conservation of small fish diversity. 展开更多
关键词 small fishes spatial distribution abundance estimation habitat selectivity Xiaosihai Lake
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Responses of soil moisture to vegetation restoration type and slope length on the loess hillslope 被引量:7
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作者 MEI Xue-mei MA Lan +3 位作者 ZHU Qing-ke WANG Shu ZHANG Dong WANG Yu 《Journal of Mountain Science》 SCIE CSCD 2018年第3期548-562,共15页
Soil moisture, a critical variable in the hydrologic cycle, is highly influenced by vegetation restoration type. However, the relationship between spatial variation of soil moisture, vegetation restoration type and sl... Soil moisture, a critical variable in the hydrologic cycle, is highly influenced by vegetation restoration type. However, the relationship between spatial variation of soil moisture, vegetation restoration type and slope length is controversial. Therefore, soil moisture across soil layers(0-400 cm depth) was measured before and after the rainy season in severe drought(2015) and normal hydrological year(2016) in three vegetation restoration areas(artificial forestland, natural forestland and grassland), on the hillslopes of the Caijiachuan Catchment in the Loess area, China. The results showed that artificial forestland had the lowest soil moisture and most severe water deficit in 100-200 cm soil layers. Water depletion was higher in artificial and natural forestlands than in natural grassland. Moreover, soil moisture in the shallow soil layers(0-100 cm) under the three vegetation restoration types did not significantly vary with slope length, but a significant increase with slope length was observed in deep soil layers(below 100 cm). In2015, a severe drought hydrological year, higher water depletion was observed at lower slope positions under three vegetation restoration types due to higher transpiration and evapotranspiration and unlikely recharge from upslope runoff. However, in 2016, a normal hydrological year, there was lower water depletion, even infiltration recharge at lower slope positions, indicating receiving a large amount of water from upslope. Vegetation restoration type, precipitation, slope length and soil depth during a rainy season, in descending order of influence, had significant effects on soil moisture. Generally, natural grassland is more beneficial for vegetation restoration than natural and artificial forestlands, and the results can provide useful information for understanding hydrological processes and improving vegetation restoration practices on the Loess Plateau 展开更多
关键词 Spatial variation Soil moisture Infiltration depth HILLSLOPE Vegetation restoration Loess Plateau
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Composition and structure of species along altitude gradient in Moghan-Sabalan rangelands,Iran 被引量:1
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作者 Sahar GHAFARI Ardavan GHORBANI +2 位作者 Mehdi MOAMERI Raoof MOSTAFAZADEH Mahmood BIDARLORD 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1209-1228,共20页
This study provides a checklist of species distributed at the altitude gradient of MoghanSabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of specie... This study provides a checklist of species distributed at the altitude gradient of MoghanSabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of species, Raunkiaer's life forms, geographical distribution, threat and endemicity status, and palatability of species along two altitudinal gradients in the sampling plots, which were conducted in eleven sites/habitats with 300 meters above sea level(masl) altitude intervals(from 100 to 3300 masl). We assessed the plant species composition with special reference to the gradient analysis, and identified overall 396 species, which was comprising 44 families and 194 genera. Results showed that Asteraceae family is by far the most species-rich family, followed by Poaceae, Fabaceae, Caryophyllaceae and Brassicaceae. Among the genera, Astragalus is the most diverse genus, followed by Allium, Veronica and Bromus, Galium, Silene and Ranunculus. Results indicated that the number of species increased as the altitude increased to 1200-1500 masl, but then starts to decline to 3300 masl. Family-to-genera ratio was 1:4.4, the family-tospecies ratio was 1:9, and the genera-to-species ratio was 1:2.04. Growth type of species analysis shows that the frequency of perennial plants was higher in the study area followed by annual species while the lower group was biennial species. The number of annuals showed a decreasing trend towards higher altitude. Hemicryptophytes and therophytes were the most frequent life forms constituted each with(41.9%). Hemicryptophytes showed an increasing trend with altitude, while therophytes showed a decreasing trend with altitude increase, followed by geophytes, chamaephytes, and phanerophytes. Results showed more than half of the species of the study area belonged to Iran-Turanian region and these species showed an increasing trend with altitude. In contrast, Sahara-Sindian species comprise a minor component of the spectrum, with decreasing trend with altitude. The rare and endangered species out of the surveyed taxonomic groups comprised 53 species in total which 29 of them are considered lower risk(LR), 13 data deficient(DD), 5 vulnerable(Vu) and with 3 rare(R) and identified endemic plants comprised 24 species. Some 56.6% species were identified as class III, 22.6% were class I and 20.8% were class II as the palatability variation. Moghan-Sabalan rangelands require strong conservation management policies in case of species loss and changing natural communities due to the occurrence of conversion into cropland, over-grazing and other anthropogenic effects. 展开更多
关键词 FLORA Floristic diversity Speciesdistribution ELEVATION Red data categories ENDEMIC Ardabili province
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Animal models for the study of hepatitis C virus infection and replication 被引量:6
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作者 Kristin L MacArthur Catherine H Wu George Y Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第23期2909-2913,共5页
Hepatitis C virus (HCV) hepatitis, initially termed non-A, non-B hepatitis, has become one of the leading causes of cirrhosis and hepatocellular carcinoma worldwide. With the help of animal models, our understanding o... Hepatitis C virus (HCV) hepatitis, initially termed non-A, non-B hepatitis, has become one of the leading causes of cirrhosis and hepatocellular carcinoma worldwide. With the help of animal models, our understanding of the virus has grown substantially from the time of initial discovery. There is a paucity of available animal models for the study of HCV, mainly because of the selective susceptibility limited to humans and primates. Recent work has focused modification of animals to permit HCV entry, replication and transmission. In this review, we highlight the currently available models for the study of HCV including chimpanzees, tupaia, mouse and rat models. Discussion will include methods of model design as well as the advantages and disadvantages of each model. Particular focus is dedicated to knowledge of pathophysiologic mechanisms of HCV infection that have been elucidated through animal studies. Research within animal models is critically important to establish a complete understanding of HCV infection, which will ultimately form the basis for future treatments and prevention of disease. 展开更多
关键词 Hepatitis C virus INFECTION REPLICATION Vac-cine Hepatitis A virus
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Numerical simulation of an algal bloom in Dianshan Lake 被引量:2
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作者 陈义中 林卫青 +1 位作者 朱建荣 卢士强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第1期231-244,共14页
A hydrodynamic model and an aquatic ecology model of Dianshan Lake,Shanghai,were built using a hydrodynamic simulation module and the water quality simulation module of Delft3D,which is an integrated modelling suite o... A hydrodynamic model and an aquatic ecology model of Dianshan Lake,Shanghai,were built using a hydrodynamic simulation module and the water quality simulation module of Delft3D,which is an integrated modelling suite offered by Deltares. The simulated water elevation,current velocity,and direction were validated with observed data to ensure the reliability of hydrodynamic model. The seasonal growth of different algae was analyzed with consideration of observed and historical data,as well as simulated results. In 2008,the dominant algae in Dianshan Lake was Bacillariophyta from February to March,while it was Chlorophyta from April to May,and Cyanophyta from July to August. In summer,the biomass of Cyanophyta grew quickly,reaching levels much higher than the peaks of Bacillariophyta and Chlorophyta. Algae blooms primarily occurred in the stagnation regions. This phenomenon indicates that water residence time can influence algal growth significantly. A longer water residence time was associated with higher algal growth. Two conclusions were drawn from several simulations: reducing the nutrients inflow had little effect on algal blooms in Dianshan Lake; however,increasing the discharge into Dianshan Lake could change the flow field characteristic and narrow the range of stagnation regions,resulting in inhibition of algal aggregation and propagation and a subsequent reduction in areas of high concentration algae. 展开更多
关键词 EUTROPHICATION algae bloom ecological model Dianshan Lake
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Responses of Dodonaea viscosa growth and soil biological properties to nitrogen and phosphorus additions in Yuanmou dry-hot valley 被引量:4
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作者 WANG Xue-mei YAN Bang-guo +3 位作者 ZHAO Guang ZHAO Ji-xia SHI Liang-tao LIU Gang-cai 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1283-1298,共16页
Nitrogen(N) and phosphorus(P) are limited nutrients in terrestrial ecosystems, and their limitation patterns are being changed by the increase in N deposition. However, little information concerns the plant growth and... Nitrogen(N) and phosphorus(P) are limited nutrients in terrestrial ecosystems, and their limitation patterns are being changed by the increase in N deposition. However, little information concerns the plant growth and the soil biological responses to N and P additions among different soils simultaneously, and these responses may contribute to understand plant-soil interaction and predict plant performance under global change. Thus, this study aimed to explore how N and P limitation changes in different soil types, and reveal the relationship between plant and soil biological responses to nutrient additions. We planted Dodonaea viscosa, a globally distributed species in three soil types(Lixisols, Regosols and Luvisols) in Yuanmou dry-hot valley in Southwest China and fertilized them factorially with N and P. The growth and biomass characters of D. viscosa, soil organic matter, available N, P contents and soil carbon(C), N, P-related enzyme activities were quantified. N addition promoted the growth and leaf N concentration of D. viscosa in Lixisols; N limitation in Lixisols was demonstrated by lower soil available N with higher urease activity. P addition promoted the growth and leaf P concentration of D. viscosa in Luvisols; severe P limitation in Luvisols was demonstrated by a higher soil available N: P ratio with higher phosphatase activity. Urease activity was negatively correlated with soil available N in Nlimited Lixisols, and phosphatase activity was negatively correlated with soil available P in P-limited Luvisols. Besides, the aboveground biomass and leaf N concentration of D. viscosa were positively correlated with soil available N in Lixisols, but the aboveground biomass was negatively correlated with soil available P. Our results show similar nutrient limitation patterns between plant and soil microorganism in the condition of enough C, and the nutrient limitations differ across soil types. With the continued N deposition, N limitation of the Lixisols in dry hot valleys is expected to be alleviated, while P limitation of the Luvisols in the mountaintop may be worse in the future, which should be considered when restoring vegetation. 展开更多
关键词 Nutrient limitation Nitrogen-phosphorus Nitrogen deposition Soil enzyme Dry-hot valley Dodonaea viscosa
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Effects of Trichoderma harzianum YC_(459) and soil types on seed germination and seedling growth in rock slope restoration 被引量:2
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作者 MA Hoseop ETTAGBOR Hans Enukwa KIM Choonsig 《Journal of Mountain Science》 SCIE CSCD 2018年第4期730-737,共8页
We carried out experiments with various concentrations of Trichoderma harzianum YC459 in different soil types(forest soil, mixed soil,merchantable soil, and leaf mold soil) to evaluate its effect on seed germination a... We carried out experiments with various concentrations of Trichoderma harzianum YC459 in different soil types(forest soil, mixed soil,merchantable soil, and leaf mold soil) to evaluate its effect on seed germination and seedling establishment of four species(Festuca arundinacea Schreb., Dianthus barbatus var. asiaticus Nakai,Lespedeza cyrtobotrya Miq., and Parthenocissus tricuspidata Planch) for rock slope restoration. We also investigated the use of drilled slanted holes on the rock slopes for seedling establishment. The results showed that T. harzianum concentration had significant effects on seed germination, seedling growth, and seedling survival for all the species with different soil types. Seed germination and survival rates peaked at 5% T. harzianum concentration with leaf mold soil and decreased as T. harzianum concentration increased from 5% to 10%. Seedling survival rates of all four species were generally lowest at 0% T. harzianum concentration in all soil types.The height of F. arundinacea and L. cyrtobotrya peaked at 5% T. harzianum concentration whereas that of D. barbatus and P. tricuspidata peaked at 10%T. harzianum concentration. We concluded that 5% T. harzianum concentration with leaf mold soil is appropriate for seed germination and seedling survival rates of most species, thus enhancing seedling establishment. Practical application of the findings of this study will contribute in the vegetation restoration of steep rocks in mountain environments. 展开更多
关键词 Dianthus barbatus Drilled holes Festuca arundinacea Lespedeza cyrtobotrya Seedling establishment Seedling survival
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Usefulness of a novel slim type Flush Knife-BT over conventional Flush Knife-BT in esophageal endoscopic submucosal dissection
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作者 Yoshiko Ohara Takashi Toyonaga +8 位作者 Namiko Hoshi Shinwa Tanaka Shinichi Baba Hiroshi Takihara Fumiaki Kawara Tsukasa Ishida Yoshinori Morita Eiji Umegaki Takeshi Azuma 《World Journal of Gastroenterology》 SCIE CAS 2017年第9期1657-1665,共9页
To investigated the usefulness of a novel slim type ball-tipped FlushKnife (FlushKnife-BTS) over ball-tipped FlushKnife (FlushKnife-BT) in functional experiments and clinical practice.METHODSIn order to evaluate the f... To investigated the usefulness of a novel slim type ball-tipped FlushKnife (FlushKnife-BTS) over ball-tipped FlushKnife (FlushKnife-BT) in functional experiments and clinical practice.METHODSIn order to evaluate the functionality of FlushKnife-BTS, water aspiration speed, resistance to knife insertion through the scope, and waterjet flushing speed were compared between FlushKnife-BTS and BT. In clinical practice, esophageal endoscopic submucosal dissection (ESD) performed using FlushKnife-BTS or BT by an experienced endoscopist between October 2015 and January 2016 were retrospectively reviewed. The treatment speed and frequency of removing and reinserting the knife to aspirate fluid and air during ESD sessions were analyzed.RESULTSFunctional experiments revealed that water aspiration speed by the endoscope equipped with a 2.8-mm working channel with FlushKnife-BTS was 7.7-fold faster than that with conventional FlushKnife-BT. Resistance to knife insertion inside the scope with a 2.8-mm working channel was reduced by 40% with FlushKnife-BTS. The waterjet flushing speed was faster with the use of FlushKnife-BT. In clinical practice, a comparison of 6 and 7 ESD using FlushKnife-BT and BTS, respectively, revealed that the median treatment speed was 25.5 mm<sup>2</sup>/min (range 19.6-30.3) in the BT group and 44.2 mm<sup>2</sup>/min (range 15.5-55.4) in the BTS group (P = 0.0633). However, the median treatment speed was significantly faster with FlushKnife-BTS when the resection size was larger than 1000 m<sup>2</sup> (n = 4, median 24.2 mm<sup>2</sup>/min, range 19.6-27.7 vs n = 4, median 47.4 mm<sup>2</sup>/min, range 44.2-55.4, P = 0.0209). The frequency of knife replacement was less in the BTS group (median 1.76 times in one hour, range 0-5.45) than in the BT group (7.02 times in one hour, range 4.23-15) (P = 0.0065).CONCLUSIONOur results indicate that FlushKnife-BTS enhances the performance of ESD, particularly for large lesions, by improving air and fluid aspiration and knife insertion during ESD and reducing the frequency of knife removal and reinsertion. 展开更多
关键词 Endoscopic submucosal dissection Novel slim type ball-tipped FlushKnife Ball-tipped FlushKnife Resistance to knife insertion Water aspiration speed
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A Quantification of the Effects of Erosion on the Productivity of Purple Soils 被引量:3
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作者 ZHAO Li JIN Jie +1 位作者 DU Shuhan LIU Gangcai 《Journal of Mountain Science》 SCIE CSCD 2012年第1期96-104,共9页
Research on the effects of soil erosion on soil productivity has attracted increasing attention.Purple soil is one of the main soil types in China and plays an important role in the national economy.However,the relati... Research on the effects of soil erosion on soil productivity has attracted increasing attention.Purple soil is one of the main soil types in China and plays an important role in the national economy.However,the relationship between erosion and the productivity of purple soils has not been well studied.The purpose of this research was to determine if soil depth,which is dependent on the rate of erosion,has an influence on crop yield and growth.Plot and pot experiments at different soil depths were performed.Results indicate that soils from different parental materials had different growth features and crop yields due to the differential fertility of the derived soils.The yield reduction rate increases exponentially with the depth of eroded soil(level of erosion).The yield reduction rate per unit eroded soil horizon(10 cm) is approximately 10.5% for maize and wheat. 展开更多
关键词 Purple soil Erosion Productivity Impact characteristics China
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