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Measuring urban thermal environment from accessibility-based perspective:A case study in a populous city
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作者 Xinyu Dong Xiaoya Li +3 位作者 Yanmei Ye Dan Su Runjia Yang Angela Lausch 《Geography and Sustainability》 CSCD 2024年第3期329-342,共14页
Understanding the spatial interaction among residents,cooling service,and heat risk area in complex urban areas is conducive to developing targeted management.However,traditional urban thermal environment assessments ... Understanding the spatial interaction among residents,cooling service,and heat risk area in complex urban areas is conducive to developing targeted management.However,traditional urban thermal environment assessments typically relied on simple linear integration of associated indicators,often neglecting the spatial interaction effect.To explore the spatial interaction among the three elements,this study proposes an accessibility-based urban thermal environment assessment framework.Using Zhengzhou,a rapidly urbanizing city,as an example,remotely sensed images from three periods(2010,2015 and 2020)were applied to extract urban green space(UGS)and hot island area(HIA).An improved two-step floating catchment area(2SFCA)method and bivariate local Moran’s I were employed to explore whether residents’clustering locations are more likely to access cooling service or to be exposed to heat risk.The results demonstrate that the UGS in the city has been expanding,whereas the HIA shrank within the inner city in 2015 and then increased in 2020.Even though the urban thermal environment may have improved in the last decade,the spatial interaction among the residents,cooling service and heat risk area could be exacerbated.Spatial autocorrelation shows an increase in locations that are disadvantageous for resident congregation.Even when sufficient cooling services were provided,residents in these areas could still be exposed to high heat risk.The developed urban thermal environment framework provides a novel insight into the residents’heat risk exposure and cooling service accessibility,and the findings could assist urban planners in targeting the improvement of extra heat exposure risk locations. 展开更多
关键词 Urban heat island Urban green space ACCESSIBILITY Remote sensing Spatial autocorrelation analysis
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关岭及相关生物群沉积与生态环境的探讨 被引量:25
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作者 汪啸风 陈孝红 +4 位作者 程龙 王传尚 Bachmann G H Sander M Hagdorn H 《古生物学报》 CAS CSCD 北大核心 2009年第3期509-526,共18页
根据近年来对黔东南至滇东关岭、兴义、贞丰和罗平等地中-晚三叠世含海生爬行动物骨架和(或)深水海百合黑色岩系(通常所称黑色页岩)化石库的研究,现将该区岩石地层单位划分,以及这些黑色岩系化石库生物组合特征、时代、分布、沉积和古... 根据近年来对黔东南至滇东关岭、兴义、贞丰和罗平等地中-晚三叠世含海生爬行动物骨架和(或)深水海百合黑色岩系(通常所称黑色页岩)化石库的研究,现将该区岩石地层单位划分,以及这些黑色岩系化石库生物组合特征、时代、分布、沉积和古地理环境概括如下:1)在关岭—兴义地区中-晚三叠世(安尼期、拉丁期和早卡尼期)地层中,至少夹有3层、甚至4层含海生爬行动物的黑色岩系化石库(或黑色"页岩"化石库),自下而上产盘县生物群、兴义生物群和关岭生物群。云南罗平地区中三叠统关岭组中新发现的"罗平生物群"与盘县生物群层位大致相当。贞丰龙场赖石科组上部新挖掘出的30m厚产创口海百合、双壳类及菊石的黑色岩系,应该是研究地区最高层位的海相三叠纪黑色岩系,时代似属晚三叠世早卡尼期晚期;2)推测这些含海生爬行动物骨架的黑色岩系化石库是在印支造山运动影响下,伴随南盘江前陆盆地隆升和闭合,在扬子克拉通台地边缘所形成的一个或几个边缘凹陷、或边缘盆地之中形成的,这些凹陷或盆地形成之初,表层水充氧,且具有很好的食物链结构,有利于各类海生生物生活;后来的海平面上升至最大海泛期,以及由此引起缺氧和含硫化氢水位的上升,导致这些凹陷逐渐变成安静、滞流的死亡之海和黑色岩系化石库;3)关岭生物群产于晚三叠世卡尼期早期小凹组下段上部黑色岩系之中,是一个典型的在滞流、缺氧且海底没有食腐动物边缘局限盆地中所形成的黑色页岩化石库,以产大量海生爬行动物和深水假浮游海百合为特征,此外还有个别的两栖类和原始龟类发现;4)产于竹杆坡组近底部黑色岩系中的兴义生物群,以产大量肿肋龙类为特点,尤以个体较小的贵州龙最为常见,共生的还有多种鱼类化石,在生物组合和产出层位上,可与阿尔卑斯南部Meride灰岩所夹黑色含沥青页岩化石库对比,时代似应归属拉丁期早或中期;大量米虾在竹杆坡组近底部含贵州龙层的发现,推测兴义生物群可能形成于台地边缘早期并不缺氧,且具有理想食物链结构的浅水、超盐的凹陷或盆地之中。由于存在浮游生物—虾—贵州龙—欧龙—虾—浮游生物所组成的生态组合和食物链结构,从而为解释以肿肋龙类为代表的兴义生物群的繁衍和多生提供了依据;接踵而来的沉积速率下降和缺氧水位的上升,以及间歇性火山作用,导致该特有生态体系的崩溃和化石库的形成。根据对贞丰挽澜竹杆坡组底部首次发现的棘皮动物的化石库的研究,指出该化石库系由海星、细小蛇尾、底栖海百合茎、海胆和海参等5类棘皮动物化石和含贵州龙骨架碎片组成,其下为8m厚夹有薄层的骨层的凝缩层沉积,后者位于硬底之上。此种沉积和埋藏模式与德国上壳灰岩早拉丁期的棘皮动物化石库类似,是在近岸海水不太浅的内陆棚的环境下,由于风暴潮作用所形成的化石库,他们与在滞流、缺氧海底、通过化石聚集所形成的化石库是不同的;5)产盘县生物群的黑色岩系化石库主要见于盘县羊件和普安青山中三叠世(安尼期)关岭组中,与云南罗平地区的"罗平生物群"在层位及生物组合上大致相当,均以含大量混鱼龙、幻龙和欧龙,以及鱼类为特点,共生的还有大量节肢动物。所不同的是后者由于靠近滨岸,故而出现大量幼年期的鱼类以及虾类和鲎类化石,推测他们形成于靠近古陆或滨岸的台缘浅水表层充氧的正常、且有时超盐的凹陷之中,时代上早于阿尔卑斯南部安尼期/拉丁期比塞娄组;其集群死亡除因后期盆地滞流、缺氧外,可能还与风暴和火山作用有关。 展开更多
关键词 关岭生物群 兴义生物群 盘县生物群 黑色岩系 海生爬行动物 中-上三叠统 边缘盆地 前陆盆地
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离子交换法在钠钙硅酸盐玻璃中原位合成银纳米颗粒的研究 被引量:17
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作者 杨修春 杜天伦 +2 位作者 HOFMEISTER Herbert DUBIEL Manferd 黄文旵 《硅酸盐学报》 EI CAS CSCD 北大核心 2005年第11期1371-1375,共5页
采用离子交换结合热处理法,在商用钠钙硅酸盐平板玻璃中原位形成2~7 nm的银纳米颗粒.利用电子探针、X射线吸收近边结构谱、透射电子显微镜和高分辨透射电子显微镜研究了银离子在玻璃中的扩散、还原和生长机理.结果表明:玻璃中同时存在... 采用离子交换结合热处理法,在商用钠钙硅酸盐平板玻璃中原位形成2~7 nm的银纳米颗粒.利用电子探针、X射线吸收近边结构谱、透射电子显微镜和高分辨透射电子显微镜研究了银离子在玻璃中的扩散、还原和生长机理.结果表明:玻璃中同时存在2价和3价铁离子,2价铁离子的存在有利于银离子被还原成中性银原子.银原子在玻璃中成核并生长成纳米颗粒.银纳米颗粒可以在离子交换时形成.提高热处理温度比延长热处理时间更有利于颗粒长大.特别当热处理温度高于玻璃转变温度时,出现Ostwald生长,导致银颗粒迅速长大,密度降低.大部分银纳米颗粒为十四面体单晶,少量为孪晶结构. 展开更多
关键词 离子交换 银纳米颗粒 十四面体单晶 形成机理
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X射线吸收精细结构谱在材料科学中的应用 被引量:9
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作者 杨修春 刘维学 +2 位作者 M.Dubiel D.Ehrt 徐政 《功能材料》 EI CAS CSCD 北大核心 2005年第8期1146-1150,共5页
简单介绍了X射线吸收精细结构谱的物理基础,数据处理方法,讨论了X射线吸收精细结构谱在元素组成,价态和结构环境方面的分析结果。结果显示,在钠钙硅酸盐平板玻璃中,二价铁离子和三价铁离子同时存在。在Ag-Na离子交换后,二价铁离子被银... 简单介绍了X射线吸收精细结构谱的物理基础,数据处理方法,讨论了X射线吸收精细结构谱在元素组成,价态和结构环境方面的分析结果。结果显示,在钠钙硅酸盐平板玻璃中,二价铁离子和三价铁离子同时存在。在Ag-Na离子交换后,二价铁离子被银离子氧化成三价铁离子。当Ti2O3和锐钛矿被分别掺入硼硅酸盐玻璃后,钛离子主要以四价存在,Ti4+离子占据五重配位点。在玻璃中同时掺入锐钛矿和还原剂C,诱导三价钛离子生成,三价钛离子占据八面体配位点,使得Ti K边预边峰高度降低。包裹在钠钙硅酸盐玻璃中的银纳米颗粒界面存在张应力,使得银晶格膨胀,银原子存在两种结构环境:Ag-O配位和Ag-Ag配位。孤立银原子的存在,使得最近邻Ag-Ag配位数显著降低。 展开更多
关键词 扩展X射线吸收精细结构谱 X射线吸收近边结构谱 价态和结构环境 过渡金属 银纳米颗粒
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银纳米颗粒在钠钙硅酸盐玻璃中的应力分析 被引量:3
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作者 杨修春 DUBIEL Manferd +1 位作者 HOFMEISTER Herbert 黄文旵 《硅酸盐学报》 EI CAS CSCD 北大核心 2006年第1期127-132,共6页
AgK边X射线吸收精细结构谱分析显示,包裹在钠钙硅酸盐玻璃中的银纳米颗粒的AgAg原子间最近邻距离大于体材料中Ag的间距,说明此时Ag晶格膨胀。晶格膨胀程度依赖于Ag纳米颗粒掺杂玻璃的制备条件。晶格膨胀表明:包裹在钠钙硅酸盐玻璃中的... AgK边X射线吸收精细结构谱分析显示,包裹在钠钙硅酸盐玻璃中的银纳米颗粒的AgAg原子间最近邻距离大于体材料中Ag的间距,说明此时Ag晶格膨胀。晶格膨胀程度依赖于Ag纳米颗粒掺杂玻璃的制备条件。晶格膨胀表明:包裹在钠钙硅酸盐玻璃中的银纳米颗粒处于张应力状态,这主要是由于Ag纳米颗粒与钠钙硅酸盐玻璃基质热失配造成的。 展开更多
关键词 银纳米颗粒 钠钙硅酸盐玻璃 晶格膨胀 热失配 张应力
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Molecular mechanism and functional consequences of lansoprazole-mediated heme oxygenase-1 induction 被引量:7
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作者 Stephanie Schulz-Geske Kati Erdmann +3 位作者 Ronald J Wong David K Stevenson Henning Schrder Nina Grosser 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第35期4392-4401,共10页
AIM: To investigate the molecular mechanism and functional consequences of heme oxygenase-1 (HO-1) activation by lansoprazole in endothelial cells and macrophages. METHODS: Expression of HO-1 mRNA was analyzed by ... AIM: To investigate the molecular mechanism and functional consequences of heme oxygenase-1 (HO-1) activation by lansoprazole in endothelial cells and macrophages. METHODS: Expression of HO-1 mRNA was analyzed by Northern blotting. Western blotting was used to determine the HO-1 and ferritin protein levels. NADPH-dependent reactive oxygen species (ROS) formation was measured with lucigenin-enhanced chemiluminescence. HO-1 promoter activity in mouse fibroblasts, stably transfected with a 15-kb HO-1 gene that drives expression of the reporter gene luciferase, was assessed usingin vivo bioluminescence imaging. RESULTS: Lansoprazole levels in endothelial cells increased HO-1 mRNA and HO-1 protein levels in macrophages. In addition, lansoprazole-induced ferritin protein levels in both cell systems. Moreover, induction of the antioxidant proteins HO-1 and ferritin by lansoprazole was followed by a decrease in NADPH- mediated ROS formation. The radical scavenging properties of lansoprazole were diminished in the presence of the HO inhibitor, chromium mesoporphyrin IX. Induction of HO-1 gene expression by lansoprazole was not related to oxidative stress or to the activation of the mitogen-activated protein kinase pathway. However, the phosphatidylinositol 3-kinase inhibitor LY294002 showed a concentration-dependent inhibition of HO-1 mRNA and promoter activity.CONCLUSION: Activation of HO-1 and ferritin may account for the gastric protection of lansoprazole and is dependent on a pathway blocked by LY294002. 展开更多
关键词 ANTIOXIDANTS FERRITIN Heme oxygenase-1 LANSOPRAZOLE Reactive oxygen species
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Land Use Changes in Himalaya and Their Impacts on Environment, Society and Economy: A Study of the Lake Region in Kumaon Himalaya, India 被引量:1
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作者 Prakash TIWARI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1029-1042,共14页
The traditional resource use structure in Himalaya has transformed considerably during the recent past, mainly owing to the growth of population and the resultant increased demand of natural resources in the region. T... The traditional resource use structure in Himalaya has transformed considerably during the recent past, mainly owing to the growth of population and the resultant increased demand of natural resources in the region. This transformation in resource use practices is particularly significant in the densely populated tracts of Himalaya. As a result, cultivated land, forests, pastures and rangelands have been deteriorated and depleted steadily and significantly leading to their conversion into degraded and non-productive lands. These rapid land use changes have not only disrupted the fragile ecological equilibrium in the mountains through indiscriminate deforestation, degradation of land resources and disruption of the hydrological cycle, but also have significant and irreversible adverse impacts on the rural economy, society, livelihood and life quality of mountain communities. It has been observed that the agricultural production has declined, water sources are drying up fast due to decreased ground water recharge and a large number of villages are facing enormous deficit of critical resources, such as food, fodder, firewood and water, mainly due to unabated deforestation. As a result, the rural people, particularly the women, have to travel considerably long distances to collect fodder and firewood and to fetching water. It is therefore highly imperative to evolve a comprehensive and integrated land use framework for the conservation of the biophysical environment and sustainable development of natural resources in Himalaya. The land use policy would help local communities in making use of their natural resources scientifically and judiciously, and thus help in the conservation of the biophysical environment and in the increasing of the productivity of natural resources. The study indicates that conservation of forests and other critical natural resources through community participation, generation of alternative means of livelihood, and employment in rural areas can help increase rural income as well as restore ecosystem services. 展开更多
关键词 subsistence agriculture population growth resource use pattern urbanization deforestation hydrological disruptions resource deficit integrated land use framework
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Characterization and Utilization of Starches Extracted from Florencia and Waxy Maize Hybrids for Tablet Formulation: Compaction Behaviour and Tablet Properties 被引量:2
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作者 Anikó Szepes Piroska Szabó-Révész +5 位作者 János Bajdik Péter Kása Jr. Miklós Neményi Roland Pap Attila József Kovács Klára Pintye-Hódi 《American Journal of Plant Sciences》 2014年第6期787-798,共12页
The aim of this work is to analyze the particle characteristics, such as shape, roundness and size, of starches extracted from Florencia and waxy maize hybrids. The micromeritics and structural properties of the sampl... The aim of this work is to analyze the particle characteristics, such as shape, roundness and size, of starches extracted from Florencia and waxy maize hybrids. The micromeritics and structural properties of the samples were examined. The evaluation of flow properties, densification and compression behaviour of the powders was carried out. Physical parameters and swelling characteristics of tablets containing Florencia and waxy maize starch were also studied. Starch samples were compared with respect to their applicability as excipients in tablet formulation. The samples exhibited identical structure and similar particle characteristics. Maize starch extracted from the Florencia dent hybrid showed better flowability and compressibility in tableting experiments, which resulted in better mechanical tablet properties. With regard to utilization as a disintegrant, Florencia starch indicated rapid and intensive swelling and proved to act more effectively in the swelling process than waxy maize starch. 展开更多
关键词 Maize STARCH MICROMERITICS X-Ray Diffraction Compression BEHAVIOUR TABLETS
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Clones or no clones:genetic structure of riparian Populus euphratica forests in Central Asia 被引量:1
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作者 Katja KRAMP Thomas SCHMITT +6 位作者 Petra LANG Michael JESCHKE Philipp SCHAFERI Dustin KULANEK ZHANG Ximing YU Ruide Frank M THOMAS 《Journal of Arid Land》 SCIE CSCD 2018年第5期750-766,共17页
Many riparian(Tugai) forests growing along rivers in arid and hyper-arid regions of Central Asia are dominated by the Euphrates poplar(Populus euphratica). Besides generative reproduction, which is only possible u... Many riparian(Tugai) forests growing along rivers in arid and hyper-arid regions of Central Asia are dominated by the Euphrates poplar(Populus euphratica). Besides generative reproduction, which is only possible upon flooding events and at a distance to the groundwater of less than 2 m, this phreatophytic tree species also reproduces vegetatively by forming clones that can cover land surface areas of several hectares. Along a gradient of groundwater distances, we investigated whether the fraction of clones in P. euphratica stands(1) increases with increasing distance to the water table;(2) is higher if supplied with water via river cut-offs; and(3) approaches 100% at a short distance to the groundwater, but at high salt concentrations in the upper soil layers, which would prevent germination and establishment of seedlings. AFLP(Amplified Fragment Length Polymorphism) analyses were conducted on leaf samples taken from mature P. euphratica trees growing at the fringes of the Taklimakan Desert in stands with different distances(2–12 m) to the groundwater at two plots at the middle and the lower reaches of the Tarim River and in a stand close to Ebinur Lake, Xinjiang, China. Genetic diversity was large among plots, but considerably smaller within plots. We found the highest genetic diversity(caused by regeneration from seeds) at plots that have a short distance to the groundwater or are supplied with additional water. There was no significant relationship between groundwater distance and clonal fraction. All investigated trees at the saline Ebinur Lake site belonged to one single clone. Our results demonstrate that the genetic pattern of this widespread species is not easily predictable even over small distances as it is a result of a complex interplay of stand history and dispersal of propagules(pollen, seeds, and vegetative diaspores) by wind and water. In conservation and restoration schemes, P. euphratica stands with a high genetic diversity and stands that grow at short distances to the water table and are regularly subjected to flooding(which favors generative over clonal reproduction) should be prioritized. 展开更多
关键词 CLONALITY floodplain forest ground water phreatophyte population genetics REJUVENATION salinity
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Effects of tree sapling diversity and nutrient addition on herb-layer invasibility in communities of subtropical species 被引量:1
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作者 Sabine Both Teng Fang +3 位作者 Martin Baruffol Bernhard Schmid Helge Bruelheide Alexandra Erfmeier 《Open Journal of Ecology》 2012年第1期1-11,共11页
Exotic species are assumed to alter ecosystem functioning. However, little is known of the relationships within vertically structured plant communities such as forests, where tree saplings interact with herbaceous spe... Exotic species are assumed to alter ecosystem functioning. However, little is known of the relationships within vertically structured plant communities such as forests, where tree saplings interact with herbaceous species, especially in the early phases of succession. This relationship was tested in a common garden experiment which assessed the impacts on tree saplings and herbaceous species following nutrient addition and the introduction of exotic herb species. The experiment was established in South- East China using four broad-leaved tree species (Elaeocarpus decipiens, Schima superba, Castanea henryi and Quercus serrata) to study the relationships between tree sapling diversity, herb-layer productivity and invasibility. Tree saplings were planted in monoculture and in mixtures of two and four species. A full factorial design was applied, within which species composition was crossed with nutrient and exotic seed-addition treatments. The seed-addition treatment included mixtures of seeds from eight exotic herb species, and herb community attributes were assessed after a four month growing season. Results indicate that certain tree species negatively affect native as well as exotic herbs;however, the high productivity of native herbs had a stronger negative impact on exotic species than tree saplings. Nutrient addition increased the productivity of exotic herbs but had no effect on native herbs. Remarkably, exotic species introduction had a negative feedback effect on the growth of tree saplings, which highlights the potential of exotic herbs to diminish tree recruitment. Although tree saplings reduced invasive effects on the herb-layer during the earliest phase of forest succession, nutrient addition had a more profound and opposite effect on these invaders. 展开更多
关键词 BEF-China Early-Successional COMMUNITIES EXOTIC Seed-Addition Fertilizer Application
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Melatonin, circadian rhythms and glaucoma: current perspective 被引量:1
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作者 Denis Gubin Dietmar Weinert 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第8期1759-1760,共2页
Primary open-angle glaucoma as a causal factor for circadian disruption:Living by the clock,in alignment with external time cues is an important condition for human health and well-being.Periodic changes in the ambien... Primary open-angle glaucoma as a causal factor for circadian disruption:Living by the clock,in alignment with external time cues is an important condition for human health and well-being.Periodic changes in the ambient light serve as a key factor to synchronize the endogenously generated circadian rhythms.The retina perceives the photic signals and transmits them to the central body clock,the suprachiasmatic nuclei(SCN),via the retinohypothalamic tract. 展开更多
关键词 AMBIENT ALIGNMENT PERIODIC
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Effects of broccoli extract and various essential oils on intestinal and faecal microflora and on xenobiotic enzymes and the antioxidant system of piglets 被引量:1
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作者 Kristin Mueller Nicole M. Blum +5 位作者 Holger Kluge Rolf Bauerfeind Julia Froehlich Anneluise Mader Karola R. Wendler Andreas S. Mueller 《Open Journal of Animal Sciences》 2012年第2期78-98,共21页
Objective: Since the ban of antibiotics as growth promoting feed additives in the EU in 2006 research in alternatives has gained importance. Phytogenic feed additives represent a heterogenous class of different plant ... Objective: Since the ban of antibiotics as growth promoting feed additives in the EU in 2006 research in alternatives has gained importance. Phytogenic feed additives represent a heterogenous class of different plant derived substances that are discussed to improve the health of farm animals by direct and indirect antioxidant effects and by influencing microbial eubiosis in the gastrointestinal tract. Consequently our study aimed to investigate the influence of broccoli extract and the essential oils of tur- meric, oregano, thyme and rosemary, as selected individual additives, on intestinal and faecal microflora, on xenobiotic enzymes, and on the antioxidant system of piglets. Methods: 48 four weeks old male weaned piglets were assigned to 6 groups of 8. The piglets were housed individually in stainless steel pens with slatted floor. The control group (Con) was fed a diet without an additive for 4 weeks. The diet of group BE contained 0.15 g/kg sulforaphane in form of a broccoli extract. 535, 282, 373 and 476 mg/kg of the essential oils of turmeric (Cuo), oregano (Oo), thyme (To) and rosemary (Ro) were added to the diets of the remaining 4 groups to stan-dardise supplementation to 150 mg/kg of the oils’ key terpene compounds ar-turmerone, carvacrol, thymol and 1,8-cineole. The composition of bacterial microflora was examined by cultivating samples of jejeunal and colonic mucosa and of faeces under specific conditions. The mRNA expression of xenobiotic and antioxidant enzymes was determined by reversing transcrip- tase real time detection PCR (RT-PCR). Total antioxidant status was assayed using the Trolox Equivalent Antioxidant Capacity (TEAC), and lipid peroxidation was determined by measuring thiobarbioturic acid reactive substances (TBA- RS). Results: Compared to Con piglets all additives positively influenced weight gain and feed conversion in week 1. Over the whole trial period no significant differences in performance parameters existed between the experimental groups. Compared to group Con performance of Ro piglets was, however, slightly impaired. Com- pared to Con piglets Cuo, Oo and To increased the ratio of Lactobacilli:E. coli attached to the jejunal mucosa, whereas BE and Ro impaired this ratio slightly. In contrast in colonic mucosa Ro improved Lactobacilli:E. coli ratio. In faecal samples an improvement of Lactobacilli:E. coli ratio could be analysed for To and Ro. Ro was the only additive that reduced the incidence rate of piglets tested positive for enterotoxic E. coli (ETEC). All additives significantly increased jejunal TEAC and reduced TBA-RS. In the liver BE, Cuo, Oo and To increased TEAC in tendency and Ro significantly. Liver TBA-RS were slightly reduced by all additives compared to Con piglets. Whereas the influence of BE, To and Ro on jejunal TEAC mainly was derived from the induction of xenobiotic and antioxidant enzymes (indirect antioxidant effects), Cuo and Oo influenced TEAC by direct antioxidant effects. Discussion and Conclusions: Our results have shown: That within the labiatae oils Oo and To have the potential to improve performance slightly. That phytogenic substances have a small but not sig- nificant influence on intestinal microflora. That phytogenic feed additives up-regulate the anti- oxidant system of piglets either by direct or by indirect antioxidant effects and that they may thereby improve health status. That within the labiatae oils Oo has a high direct antioxidant potential whereas Ro potently induces xenobiotic and antioxidant enzymes. That broccoli extract is an attractive new phytogenic additive, improving antioxidant status by indirect antioxidant effects. That defined combinations of selected phytogenic substances may produce additive effects. That health promoting effects of phytogenic additives in the future should be studied systematically under the challenge with pathogenic microorganisms or food derived to-xins. 展开更多
关键词 Pigs Phytogenic Feed Additives BROCCOLI Extract Essential Oils XENOBIOTIC ENZYMES Antioxidant System
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Synthesis and Characterization of Various Protein <i>α</i>-Lactalbumin Nanotubes Structures by Chemical Hydrolysis Method 被引量:1
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作者 Pegah Esmaeilzadeh Zahra Fakhroueian +1 位作者 Pouriya Esmaeilzadeh Narges Mohammadi 《Advances in Nanoparticles》 2013年第2期154-164,共11页
New water-based nanofluids including unparalleled milk protein α-lactalbumin hollow nano-bio-tubes using low cost, available and advanced partial chemical hydrolysis strategy in bottom-up nano-assembly have been empl... New water-based nanofluids including unparalleled milk protein α-lactalbumin hollow nano-bio-tubes using low cost, available and advanced partial chemical hydrolysis strategy in bottom-up nano-assembly have been employed in this work. The aqueous sol-gel chemistry in nanotechnology which we selected for this goal offers new fabrication as interesting smart protein nanotubes. The kinds of nanometer sized tubular structures such as waved, helically coiled, bent, bamboo-shaped, bead-like and branched single-walled protein nanotubes (SWPNTs) with a range of 3 - 8 nm in outer diameters were produced by this method. Complete characterization for natural produced nanotubes including SEM, TEM images, G bond and D bond in Raman spectroscopy, XRD patterns, DLS (Dynamic Light Scattering) and FTIR analysis were evaluated which they are most significant experiments in synthesized protein nanotubes soluble in clear water nanofluids and stabilization of transparent nanofluids was proved within more than one year after preparation. Various necessary ligand ion salts such as Mn2+, Zn2+ and Ca2+ or mixtures as bridge makers and producing biological self-assembly hollow SWPNTs were performed and we focused on new chemical technology under specific acidic hydrolysis method not conventional enzymatic proteolysis and applying surfactants, pH reagent, Tris-HCl buffer, polar solvent which could be produced by β-sheet stacked hydrolysed protein α-lactalbumin mechanism under appropriate conditions to achieving high efficiency new protein nanotubes skeleton. They can be promising materials applied in food science, diet nutrition, nanomedicine, nano-biotechnology and surgery. 展开更多
关键词 NANOBIOTECHNOLOGY Milk PROTEIN NANOTUBES Helical Self-Assembly Water-Based Nanofluids CHEMICAL Hydrolysis Nanomedicine
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First Late Triassic Record of a Paleoentomofauna from South America(Malargüe Basin,Mendoza Province,Argentina)
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作者 Carsten BRAUCKMANN Oscar F.GALLEGO +4 位作者 Norbert HAUSCHKE Rafael G.MARTINS-NETO Elke GROENING Jan-M.ILGER María B.LARA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第4期915-924,共10页
Late Middle Triassic to early Late Triassic insects from Argentina have been previously described from the Bermejo and Cuyana Basins where they have been recovered from the Ischichuca-Los Rastros and Potrerillos-Cache... Late Middle Triassic to early Late Triassic insects from Argentina have been previously described from the Bermejo and Cuyana Basins where they have been recovered from the Ischichuca-Los Rastros and Potrerillos-Cacheuta Formations, respectively. The insect fauna discussed herein was collected during field studies in 1986/1987 from the Llantenes section (Norian to Rhaetian? Late Triassic), which is situated in the Malargiie Basin in southern Mendoza province. The insect remains were found in the upper part of the Llantenes section (Llantenes Formation), which is built up of two coarsening-upwards cycles reflecting a deltaic progradation of a fluvial into a lacustrine environment (lower part), succeeded by repeated progradatious into a floodplaindominated environment (upper part; with finds of insects, conchostracans, fish remains, plant fragments, and drifted logs). The new finds represent the youngest Triassic insect records described from Argentina and even from South America in its entirety. There is only one contemporaneous fossil assemblage in Gondwana: in the Ciarence/Moreton Basin (Aberdare Conglomerate; Late Norian) in Australia. The new Triassic insects include an impression of an isolated Mecopterida-like wing (Mendozachorista volkheimeri gen. et sp. nov.; Mendozachoristidae fam. nov.), coleopteran elytra of the Permosynidae (Ademosyne rosenfeldi sp. nov. and Ademosyne Uantenesensis sp. nov.) and other isolated body fragments. This new Late Triassic entomofauna from Argentina is of considerable importance in the reconstruction of the biotic recovery of continental environments in Gondwana after the catastrophic mass extinction at the P/T boundary. 展开更多
关键词 Mecopterida COLEOPTERA Late Triassic Liantenes Formation Malargiie Basin ARGENTINA
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Influence of External Plasticization on Rheological and Thermal Properties of Cellulose Acetate with Respect to Its Foamability
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作者 Stefan Zepnik Stephan Kabasci +1 位作者 Hans-Joachim Radusch and Thomas Wodke 《材料科学与工程(中英文A版)》 2012年第2期152-163,共12页
关键词 醋酸纤维素 流变性能 热性能 塑化 起泡性 玻璃化转变温度 增塑剂 塑料泡沫
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Adsorption/Desorption of Low-density Lipoprotein on a Heparinized Surface of Gold Sensors
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作者 LAN Ping JI Jing +4 位作者 HUANG Xiao-Jun GUDURU Deepak GROTH Thomas VIENKEN Jorg D1NG Hui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期323-328,共6页
Heparin has been considered to be a potentially useful ligand for low-density lipoprotein(LDL) detection and analysis in a clinical context.In order to construct an affinity surface for preferential adsorption of LD... Heparin has been considered to be a potentially useful ligand for low-density lipoprotein(LDL) detection and analysis in a clinical context.In order to construct an affinity surface for preferential adsorption of LDL,heparin-modified gold surface(GS-Hep) was fabricated by a self-assembling method and hydrophobic-modified gold surfaces(GS-Hydro) was used as a control.The morphologies of the modified gold surfaces were investigated by atomic force microscopy(AFM) and the quantity of heparin bound to gold surface was assayed by the toluidine blue(TB) colorimetric method.Water contact angles were determined to investigate wettability on GS-Hep and GS-Hydro.Surface plasmon resonance(SPR) technique was used subsequently to detect the selective binding of LDL with heparin.And the investigation on the effect of pH on LDL adsorption suggests that lower pH lead to higher quantities of LDL adsorption on GS-Hep.Compared with GS-Hydro,GS-Hep is selective for LDL from both single and binary protein solutions.Moreover,adsorbed LDL on GS-Hep could be washed off by injecting elution solution,such as NaCl solution,for the purpose of the regeneration of GS-Hep for further LDL adsorption. 展开更多
关键词 ADSORPTION/DESORPTION Low-density lipoprotein(LDL) Heparinized surface Surface plasmon resonance
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Women’s Experiences with Gender Violence and the Mental Health Impact: Qualitative Findings
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作者 Venus Medina Maldonado Margarete Landenberger Marbella Camacaro Cuevas 《Open Journal of Nursing》 2015年第2期104-108,共5页
The purpose of this study was to describe women’s experiences with gender violence and the impact on mental health. The research was a qualitative observational study. Participants were n = 72 women clients of (02) P... The purpose of this study was to describe women’s experiences with gender violence and the impact on mental health. The research was a qualitative observational study. Participants were n = 72 women clients of (02) Primary Health Centers at the University of Carabobo-Venezuela. The technique to gather the information was focus group discussion (FGD). The interpretation of data was an analytical process based on Mayring’s approach. The principal findings showed that, women clients of primary health centers experienced different levels of violence in everyday life. Physical violence was the most frequent abuse reported by victims. Death threats were the most frequent conduct used by the partners in terms of psychological violence. Women expressed being under the control of a dominant partner without physical aggression or threats, but they felt a lack of autonomy. Additionally, women who experienced different levels of abuse specified some symptoms that could suggest an impact on mental health. In conclusion, women naturalized dominance and control because they understood this kind of abuse as normal behavior between relationship partners. 展开更多
关键词 VIOLENCE against Women MENTAL HEALTH Primary HEALTH CARE
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Influence of Modified ZnO Quantum Dots and Nanostructures as New Antibacterials
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作者 Zahra Fakhroueian Faraz M. Harsini +3 位作者 Firoozeh Chalabian Fatemeh Katouzian Azizollah Shafiekhani Pegah Esmaeilzadeh 《Advances in Nanoparticles》 2013年第3期247-258,共12页
Antibacterial activities of various spherical zinc oxide nanoparticles and nano special morphological structures including quantum dots, nanorod arrays, nanoporous shapes and needle-like crystals had been investigated... Antibacterial activities of various spherical zinc oxide nanoparticles and nano special morphological structures including quantum dots, nanorod arrays, nanoporous shapes and needle-like crystals had been investigated as new nanomedicine compounds. Also antibacterial activity based on minimal inhibitory concentration and the growth inhibitory zone (well method) was evaluated. ZnO nanostructures were fabricated by novel hydrolysis sol-gel-hydrothermal process followed with rapid quenching as new technique using glycerine, vegetable fatty esters such as coconut, sunflower and Lauric alcohol ethoxylated as organic templates soluble in eco-friendly nanofluids. The results showed that Bacillus anthracis and Pseudomonas aerogenes were extremely sensitive to treatment with unique ZnO nanostructured. Their growth inhibitory zone presented 30 mm and 25 mm inhibition zone with better inhibitory effect compared to the Gentamicin antibiotic standard. ZnO nanostructures had also been indicated to have a wide range of antibacterial activities against both Gram-positive and Gram-negative bacteria especially more effective on (gr+) species using the growth inhibitory zone. We could design and make significant formulations of fatty acids and esters-capped ZnO quantum dots nanofluids which created high promising agents for controlling Anthrax, Staphylococcus epidermidis and their influences in antimicrobial properties with low cost for future. 展开更多
关键词 NANOBIOTECHNOLOGY ANTIBACTERIAL Activity HYDROLYSIS Sol-Gel-Hydrothermal ZnO Quantum DOTS MIC and Well Method Complex Defects
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Dual Mode-Multiple Output SEPIC Converter Integrated with Passive Ripple Cancelling Circuit for Standalone PV Energy Harvesting System
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作者 Sharmin Sobhan Md. Ashraful Hoque +2 位作者 Golam Sarowar Tanvir Ahmad Abdul Mannan Farhan 《Journal of Power and Energy Engineering》 2016年第11期1-18,共18页
This document addresses an exhaustive standalone Photovoltaic (PV) energy harvesting system considering two crucial issues: system efficiency and cost effectiveness. It contributes a compact resolution with a combined... This document addresses an exhaustive standalone Photovoltaic (PV) energy harvesting system considering two crucial issues: system efficiency and cost effectiveness. It contributes a compact resolution with a combined feature of Dual Mode-Multiple Output (DMMO) associated with input ripple reduction technique. Control strategy incorporates with aspect of Maximum Power Point Tracking (MPPT) and output voltage levels regulation. A theoretical analysis is conducted to evaluate the effect of ripple current on PV power. Proposed dual mode converter achieves efficiency of 98.36% and 97.76% respectively for mode-1 and mode-2 operation. However, simulation is performed applying MATLAB/SIMULINK tools to analyze the feasibility of the recommended system. 展开更多
关键词 Photovoltaic Cell Current Ripple Reduction Dual Mode Converter Multiple Outputs Efficiency
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Survival after surgery for acute type A aortic dissection in octogenarians
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作者 Antonio Fiore Javier Rodriguez Lega +25 位作者 Joscha Buech Giovanni Mariscalco Andrea Perrotti Konrad Wisniewski Angel G.Pinto Till Demal Jan Rocek Petr Kacer Giuseppe Gatti Igor Vendramin Mauro Rinaldi Eduard Quintana Dario Di Perna Francesco Nappi Mark Field Amer Harky Matteo Pettinari Angelo M.Dell’Aquila Francesco Onorati Mikko Jormalainen Tatu Juvonen Timo Mäkikallio Caroline Radner Sven Peterss Vito D’Andrea Fausto Biancari 《Journal of Geriatric Cardiology》 SCIE CAS 2024年第11期1015-1025,共11页
Objective To evaluate the benefits of surgical repair acute type A aortic dissection(ATAAD)on survival of octogenarians.Methods Patients who underwent surgery for acute ATAAD from the multicenter European Registry of ... Objective To evaluate the benefits of surgical repair acute type A aortic dissection(ATAAD)on survival of octogenarians.Methods Patients who underwent surgery for acute ATAAD from the multicenter European Registry of Type A Aortic Dissection(ERTAAD)were the subjects of the present analysis.Results 326(8.4%)patients were aged≥80 years.Among 280 propensity score matched pairs,in-hospital mortality was 30.0%in patients aged≥80 years and 20.0%in younger patients(P=0.006),while 10-year mortality were 93.2%and 48.0%,respectively(P<0.001).The hazard of mortality was higher among octogenarians up to two years after surgery,but it became comparable to that of younger patients up to 5 years.Among patients who survived 3 months after surgery,10-year relative survival was 0.77 in patients aged<80 years,and 0.46 in patients aged≥80 years.Relative survival of octogenarians decreased markedly 5 years after surgery.Age≥85 years,glomerular filtration rate,preoperative invasive ventilation,preoperative mesenteric mal-perfusion and aortic root replacement were independent predictors of in-hospital mortality among octogenarians(AUC=0.792;E:O ratio=0.991;CITL=0.016;slope=1.096).An additive score was developed.A risk score≤1 was observed in 68.4%of patients,and their in-hospital mortality was 20.9%.Conclusions Provided a thoughtful patient selection,surgery may provide a survival benefit in patients aged≥80 years with ATAAD that,when compared to younger patients and the general population,may last up to 5 years after the procedure.These findings have significant epidemiologic and clinical relevance because of the increasing longevity of the population of the Western countries. 展开更多
关键词 surgery dissection Survival
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