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Evaluation of Application Value of 30 Introduced Flowering Shrubs in Landscape in Hefei City Based on AHP Method
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作者 DAI Mengting ZHAO Zhiyan +2 位作者 GAO Feiyan GAO Miaomiao CHEN Jiaxin 《Journal of Landscape Research》 2024年第3期70-72,79,共4页
The application effect of 30 introduced flowering shrubs in landscape in Hefei City was comprehensively evaluated by the analytic hierarchy process(APH).A comprehensive evaluation model was established by using factor... The application effect of 30 introduced flowering shrubs in landscape in Hefei City was comprehensively evaluated by the analytic hierarchy process(APH).A comprehensive evaluation model was established by using factors such as plant type,resistance and drought tolerance of introduced flowering shrubs.The results show that the application effect of grade-I introduced flowering shrubs(including 12 kinds,e.g.Lantanacamara)was the best(j≥2.6),and that of grade-II introduced flowering shrubs(including 14 kinds,e.g.Abelia×grandiflora‘Francis Mason’)was better(2.2≤j<2.6),while that of grade-III introduced flowering shrubs(including 4 kinds,e.g.Ligustrum×vicaryi)was moderate(j<2.2).The evaluation results can provide reference for the application effect of introduced flowering shrubs in landscape in Hefei City. 展开更多
关键词 introduced flowering shrubs Landscape effect Comprehensive evaluation analytic hierarchy process
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Intercontinental comparison of phylogenetic relatedness in introduced plants at the transition from naturalization to invasion:A case study on the floras of South Africa and China 被引量:1
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作者 Hong Qian 《Plant Diversity》 SCIE CAS CSCD 2023年第4期363-368,共6页
Invasive species may pose significant threats to biodiversity and ecosystem structure and functioning.The number of introduced species that have become invasive is substantial and is rapidly increasing.Identifying pot... Invasive species may pose significant threats to biodiversity and ecosystem structure and functioning.The number of introduced species that have become invasive is substantial and is rapidly increasing.Identifying potentially invasive species and preventing their expansion are of critical importance in invasion ecology.Phylogenetic relatedness between invasive and native species has been used in predicting invasion success.Previous studies on the phylogenetic relatedness of plants at the transition from naturalization to invasion have shown mixed results,which may be because different methods were used in different studies.Here,I use the same method to analyze two comprehensive data sets from South Africa and China,using two phylogenetic metrics reflecting deep and shallow evolutionary histories,to address the question whether the probability of becoming invasive is higher for naturalized species distantly related to the native flora.My study suggests that the probability of becoming invasive is higher for naturalized species closely related to the native flora.The finding of my study is consistent with Darwin's preadaptation hypothesis. 展开更多
关键词 anGIOSPERMS Exotic species introduced species Invasive species Naturalized species Phylogenetic relatedness
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Introducer法经皮内镜下胃造瘘术对食管癌伴吞咽困难患者的效果 被引量:1
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作者 张丽娟 王改琳 朱芬英 《食管疾病》 2024年第1期39-43,共5页
目的探讨Introducer法经皮内镜下胃造瘘术治疗食管癌伴吞咽困难患者的效果。方法选取河南科技大学第一附属医院微创肿瘤科2020年3月至2022年9月收治的96例食管癌伴吞咽困难患者作为研究对象,根据手术方式将患者分为Pull法组和Introduce... 目的探讨Introducer法经皮内镜下胃造瘘术治疗食管癌伴吞咽困难患者的效果。方法选取河南科技大学第一附属医院微创肿瘤科2020年3月至2022年9月收治的96例食管癌伴吞咽困难患者作为研究对象,根据手术方式将患者分为Pull法组和Introducer法组各48例,分别用Pull法或Introducer法行经皮内镜下胃造瘘术建立肠内营养通路,对比两组患者造瘘管更换率、营养状况、炎症因子水平和并发症发生率。结果两组患者院外随访期间造瘘管更换率对比差异无统计学意义(P>0.05);治疗后,Introducer法组患者TSF、上臂肌围、FFMI、血红蛋白、白蛋白、前白蛋白水平均高于Pull法组(P<0.05);治疗后,Introducer法组IL-6水平、TNF-α水平均低于Pull法组(P<0.05);两组患者术后并发症总发生率对比差异无统计学意义(P>0.05)。结论Introducer法经皮内镜下胃造瘘术可以改善食管癌伴吞咽困难患者的自身营养水平,降低炎症反应水平。 展开更多
关键词 introducer法经皮内镜下胃造瘘术 食管癌 吞咽困难 营养指标 炎症因子
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Autonomous Recommendation of Fault Detection Algorithms for Spacecraft 被引量:1
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作者 Wenbo Li Baoling Ning 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期273-275,共3页
Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measur... Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets. 展开更多
关键词 FAULT introducing LETTER
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Avian malaria,haematocrit,and body condition in invasive wetland passerines settled in southwestern Spain
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作者 Jaime Muriel Luz Garcia-Longoria +2 位作者 Sergio Magallanes Juan Antonio Ortiz Alfonso Marzal 《Avian Research》 SCIE CSCD 2023年第1期99-107,共9页
Avian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds.Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native pas... Avian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds.Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native passerines,with exotic species underrepresented.However,introduced species may carry on and spread new pathogens to native species,and play a role on parasite transmission cycle in invaded bird communities as pathogen reservoir.Here,we molecularly assess the prevalence and diversity of haemosporidian parasites in three introduced wetland passerines(the Red Avadavat Amandava amandava,the Yellow-crowned Bishop Euplectes afer,and the Common Waxbill Estrilda astrild)captured during the same season in southwestern Spain.We also explored the relation between parasite infection,body condition,haematocrit,and uropygial gland volume.We detected an overall parasite prevalence of 3.55%,where Common Waxbills showed higher prevalence(6.94%)than Red Avadavats(1.51%).None Yellow-crowned Bishops were infected with haemosporidians.Almost 60%of infections were caused by Leucocytozoon,and about 40%by Plasmodium.We identified four unique lineages of Plasmodium and three of Leucocytozoon.Moreover,91%of the identified host-parasite interactions represented new host records for these haemosporidian parasites.Parasite infection was not related to body condition,haematocrit,and uropygial gland volume of the wetland passerines.Haematocrit values varied seasonally among bird species.Additionally,haematocrit was positively related to body condition in the Yellow-crowned Bishops,but not in the other species.Red Avadavats had higher haematocrit levels than Yellow-crowned Bishops,whereas Common Waxbills showed the lower haematocrit values.The uropygial gland volume was positively correlated with body condition in all bird species.Common Waxbills showed higher uropygial gland volumes related to their body size than birds from other two species.These outcomes highlight the importance of exotic invasive species in the transmission dynamics of haemosporidian parasites. 展开更多
关键词 Avian malaria Exotic species introduced birds LEUCOCYtoZOON PLASMODIUM Uropygial gland
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Does a shift in shade tolerance as suggested by seedling morphology explain differences in regeneration success of northern red oak in native and introduced ranges? 被引量:1
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作者 Peter Nosko Kerri Moreau +2 位作者 Christian Kuehne Kelly C.Major Jürgen Bauhus 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期949-962,共14页
Across North America, forests dominated by Quercus rubra L. (northern red oak), a moderately shade-tolerant tree species, are undergoing successional replacement by shade-tolerant competitors. Under closed canopies, Q... Across North America, forests dominated by Quercus rubra L. (northern red oak), a moderately shade-tolerant tree species, are undergoing successional replacement by shade-tolerant competitors. Under closed canopies, Q. rubra seedlings are unable to compete with these shade-tolerant species and do not recruit to upper forest strata. In Europe, natural regeneration of introduced Q. rubra is often successful despite the absence of fire, which promotes regeneration in the native range. Considering that understorey light availability is a major factor affecting recruitment of seedlings, we hypothesized that Q. rubra seedlings are more shade tolerant in the introduced range than in the native range. Morphological traits and biomass allocation patterns of seedlings indicative of shade tolerance were compared for Q. rubra and three co-occurring native species in two closed-canopy forests in the native range (Ontario, Canada) and introduced range (Baden-Württemburg, Germany). In the native range, Q. rubra allocated a greater proportion of biomass to roots, while in the introduced range, growth and allocation patterns favored the development of leaves. Q. rubra seedlings had greater annual increases in height, diameter and biomass in the introduced range. Q. rubra seedlings in the introduced range were also younger;however, they had a mean area per leaf and a total leaf area per seedling that were five times greater than seedlings in the native range. Such differences in morphological traits and allocation patterns support the hypothesis that Q. rubra expresses greater shade tolerance in the introduced range, and that natural regeneration of Q. rubra is not as limited by shade as in the native range. The ability of Q. rubra seedlings to grow faster under closed canopies in Europe may explain the discrepancy in regeneration success of this species in native and introduced ranges. Future research should confirm findings of this study over a greater geographical range in native and introduced ecosystems, and examine the genetic and environmental bases of observed differences in plant traits. 展开更多
关键词 Alien species Cross-continental study Forest regeneration introduced species Seedling morphology Plant functional traits Quercus rubra
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Genetic and Agronomic Parameter Estimates of Growth, Yield and Related Traits of Maize (Zea mays L.) under Different Rates of Nitrogen Fertilization
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作者 Prince Emmanuel Norman Lansana Kamara +6 位作者 Aloysius Beah Kelvin Sahr Gborie Francess Sia Saquee Sheku Alfred Kanu Fayia Augustine Kassoh Yvonne Sylvia Gloria Ethel Norman Abdul Salaam Kargbo 《American Journal of Plant Sciences》 CAS 2024年第4期274-291,共18页
This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in... This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup>) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p < 0.05) influenced grain yield production. Mean grain yields and economic parameter estimates increased with increasing nitrogen rates, with the 30 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup> plots exhibiting the lowest and highest grain yields of 1238 kg∙ha<sup>−</sup><sup>1</sup> and 2098 kg∙ha<sup>−</sup><sup>1</sup>, respectively. Variety and nitrogen effects on partial factor productivity (PFP<sub>N</sub>), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p < 0.05) by these factors. The highest PFP<sub>N</sub> (41.3 kg grain kg<sup>−</sup><sup>1</sup>∙N) and AEN (29.4 kg grain kg<sup>−</sup><sup>1</sup>∙N) were obtained in the 30 kg∙N∙ha<sup>−</sup><sup>1</sup> plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL<sup>−</sup><sup>1</sup> spent on N) were obtained in the 180 kg∙N∙ha<sup>−</sup><sup>1</sup>. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fertilization and improved farming practices that could be exploited for increased productivity of maize. 展开更多
关键词 Nitrogen Rates Genetic and Agronomic Estimates introduced Genotypes Grain Yield Zea mays
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Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses
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作者 Han Shi Xi Peng +6 位作者 Yong-Jiao Zhou Ai-Ying Wang Xue-Kai Sun Na Li Quan-Sheng Bao Gude Buri Guang-You Hao 《Forest Ecosystems》 SCIE CSCD 2024年第4期491-501,共11页
Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patte... Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patterns in species-specific responses to extreme droughts.Here,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast China.We assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation index.The results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar plantations.The RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy effect.In contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial growth.Furthermore,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth rate.This study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and response.Our study improves our understanding of forest responses to extreme drought and highlights species differences in climate responses,offering crucial insights for optimizing species selection in sustainable afforestation and forest management in water-limited regions under the influence of climate change. 展开更多
关键词 introduced tree species Native tree species NDVI Severe drought Tree-ring width
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Trip to China July 2024
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作者 Hammad Ahsan 《China's Foreign Trade》 2024年第4期62-63,共2页
I recently got the opportunity to visit China to attend a seminar organized by the China Counsel for the Promotion of International Trade(CCPIT),for participants from the Belt and Road Initiative(BRI)countries.The pur... I recently got the opportunity to visit China to attend a seminar organized by the China Counsel for the Promotion of International Trade(CCPIT),for participants from the Belt and Road Initiative(BRI)countries.The purpose of the seminar was to invite the delegates from BRI countries,and give them firsthand experience of the Chinese development miracle by introducing them to Chinese history,its governance methodology and how it has managed to carry out its significant progress in the last three decades,for example,by following policies that facilitated entrepreneurship,and providing businesses the right kind of platform. 展开更多
关键词 CARRY TRADE introducing
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Discovering Shanghai by Citywalks
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作者 LIU TING 《China Today》 2024年第9期64-66,共3页
As an enthusiast of travelling,a young French entrepreneur has dedicated her life to sharing the vitality of China’s eastern economic hub with more people.ON the streets of Shanghai,China’s eastern mega city,you can... As an enthusiast of travelling,a young French entrepreneur has dedicated her life to sharing the vitality of China’s eastern economic hub with more people.ON the streets of Shanghai,China’s eastern mega city,you can often see a young French woman leading a group of tourists around the city on citywalks,introducing the history and culture of the metropolis to them in Chinese,English,and French. 展开更多
关键词 introducing FRENCH TRAVELLING
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Boosting New Productivity Chinese automaker SAIC-GM-Wuling gears up for the boom of NEV market
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作者 Guo Xixian 《China Report ASEAN》 2024年第7期42-43,共2页
During the annual meeting of the National People’s Congress(NPC),China’s top legislature,in March,President Xi Jinping stressed focusing on high-quality development as the top priority and developing new quality pro... During the annual meeting of the National People’s Congress(NPC),China’s top legislature,in March,President Xi Jinping stressed focusing on high-quality development as the top priority and developing new quality productive forces according to local conditions while deliberating with lawmakers from Jiangsu Province.Following the path that President Xi emphasized,SAIC-GM-Wuling Automobile Co.,Ltd.has been committed to modernizing research and development(R&D),introducing intelligent manufacturing,upgrading the automobile industry. 展开更多
关键词 introducing MARKET AUtoMOBILE
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EchoNavigator virtual marker and Agilis NxT steerable introducer facilitate transseptal transcatheter closure of mitral paravalvular leak
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作者 Jung-Cheng Hsu Chong-Sun Khoi +3 位作者 Shan-Hui Huang Yi-Yao Chang Shu-Lu Chen Yen-Wen Wu 《World Journal of Clinical Cases》 SCIE 2022年第13期4236-4241,共6页
BACKGROUND Paravalvular leak(PVL),also known as paravalvular prosthetic regurgitation,is not a rare complication after surgical valve replacement,and it may cause varying degrees of heart failure.The transcatheter clo... BACKGROUND Paravalvular leak(PVL),also known as paravalvular prosthetic regurgitation,is not a rare complication after surgical valve replacement,and it may cause varying degrees of heart failure.The transcatheter closure of PVL is technically demanding and challenging.CASE SUMMARY A 68-year-old man presented with degenerative mitral regurgitation with heart failure,New York Heart Association functional class 3.He received bioprosthetic mitral valve replacement in December 2019.PVL was noted at the location of the aorto-mitral curtain in transesophageal echocardiography without signs of endocarditis or dehiscence of the bioprosthetic valve.Transseptal transcatheter closure of the mitral PVL was performed efficiently using the EchoNavigator virtual marker and Agilis NxT steerable introducer.CONCLUSION This case highlights that the EchoNavigator virtual marker and Agilis NxT steerable introducer can facilitate transseptal transcatheter closure of mitral PVL by reducing the procedure time and contrast media. 展开更多
关键词 Paravalvular leak Paravalvular prosthetic regurgitation EchoNavigator Steerable introducer Case report
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Miss Jiang is asking Ms.Brown to introduce a booth to her
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《中国会展》 2003年第20期48-49,共2页
江小姐:布朗女士:江小姐:布朗女士:江小姐:布朗女士:江小姐:布朗女士: 参考译文布朗女士,经过认真研究,我们公司决定参加本次国际家居用品展.具体参展事宜由我负责。很高兴贵公司能来参展。你们一定不虚此行。
关键词 Miss Jiang is asking Ms.Brown to introduce a booth to her 家居用品
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GENETIC CONSEQUENCES OF INTRODUCED Gouramy Helostoma Temminckii (Pisces: Helostomatidae) IN BRUNEI'S WETLAND
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作者 H.S.Zohrah P.H.C.Fauzani C. S. Jen O. Norsuzieyanti 《湿地科学》 CSCD 2003年第1期51-56,共6页
Kissing gouramy (Helostoma temminckii) was introduced into Tasek Merimbun in the 1980's. We studied their genetic profile using allozyme electrophoresis and found that all loci were monomorphic. The loss of hetero... Kissing gouramy (Helostoma temminckii) was introduced into Tasek Merimbun in the 1980's. We studied their genetic profile using allozyme electrophoresis and found that all loci were monomorphic. The loss of heterozygotes may suggest that the gouramy are inbreds. They must have reproduced by repeated sib-mating over the years. The severe drought in Tasek Merimbun may have aggravated the genetic erosion further. The genetic variability of kissing gouramy in terms of % polymorphic loci, mean number of alleles per loci and observed heterozygosity level were lower than cyprinids in the same lake and kissing gouramy from the wild. We also note that kissing gouramy is a fast grower and may threaten the livelihood of indigenous fishes in the lake. 展开更多
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Analysis of Genetic Diversity and Differentiation of Seven Stocks of Litopenaeus vannamei Using Microsatellite Markers 被引量:7
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作者 ZHANG Kai WANG Weiji +2 位作者 LI Weiya ZHANG Quanqi KONG Jie 《Journal of Ocean University of China》 SCIE CAS 2014年第4期647-656,共10页
Seven microsatellite markers were used to evaluate the genetic diversity and differentiation of seven stocks of Litopenaeus vannamei, which were introduced from Central and South America to China. All seven microsatel... Seven microsatellite markers were used to evaluate the genetic diversity and differentiation of seven stocks of Litopenaeus vannamei, which were introduced from Central and South America to China. All seven microsatellite loci were polymorphic, with polymorphism information content(PIC) values ranging from 0.593 to 0.952. Totally 92 alleles were identified, and the number of alleles(Na) and effective alleles(Ne) varied between 4 and 21 and 2.7 and 14.6, respectively. Observed heterozygosity(Ho) values were lower than the expected heterozygosity(He) values(0.526–0.754), which indicated that the seven stocks possessed a rich genetic diversity. Thirty-seven tests were detected for reasonable significant deviation from Hardy-Weinberg equilibrium. Fis values were positive at five loci, suggesting that there was a relatively high degree of inbreeding within stocks. Pairwise Fst values ranged from 0.0225 to 0.151, and most of the stock pairs were moderately differentiated. Genetic distance and cluster analysis using UPGMA revealed a close genetic relationship of L. vannamei between Pop2 and Pop3. AMOVA indicated that the genetic variation among stocks(11.3%) was much lower than that within stocks(88.7%). Although the seven stocks had a certain degree of genetic differentiation and a rich genetic diversity, there is an increasing risk of decreased performance due to inbreeding in subsequent generations. 展开更多
关键词 Litopenaeus vannamei MICROSATELLITE introduced stock genetic diversity genetic differentiation
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Effects of Hydroxyl Radicals on Introduced Organisms of Ship's Ballast Water Based Micro-Gap Discharge 被引量:2
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作者 白敏冬 张芝涛 +2 位作者 白敏菂 杨波 白希尧 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第2期206-210,共5页
With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship's ballast water.... With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship's ballast water. The surface morphology of Al2O3 dielectric layer was analysed using Atomic Force Microscopy (AFM), where the size of Al2O3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship's ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase (CAT), Peroxidase (POD) and Superoxide dismutase (SOD). In addition, the quality of the ballast water was greatly improved. 展开更多
关键词 micro-gap discharge α-Al2O3 dielectric layers introduced organisms hydroxyl radical biochemistry effect
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Usefulness of percutaneous endoscopic gastrostomy for supportive therapy of advanced aerodigestive cancer 被引量:1
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作者 Haruei Ogino Hirotada Akiho 《World Journal of Gastrointestinal Pathophysiology》 CAS 2013年第4期119-125,共7页
Aerodigestive cancer, like esophageal cancer or head and neck cancer, is well known to have a poor prognosis. It is often diagnosed in the late stages, with dysphagia being the major symptom. Insufficient nutrition an... Aerodigestive cancer, like esophageal cancer or head and neck cancer, is well known to have a poor prognosis. It is often diagnosed in the late stages, with dysphagia being the major symptom. Insufficient nutrition and lack of stimulation of the intestinal mucosa may worsen immune compromise due to toxic side effects. A poor nutritional status is a significant prognostic factor for increased mortality. Therefore, it is most important to optimize enteral nutrition in patients with aerodigestive cancer before and during treatment, as well as during palliative treatment. Percutaneous endoscopic gastrostomy(PEG) may be useful for nutritional support. However, PEG tube placement is limited by digestive tract stenosis and is an invasive endoscopic procedure with a risk of complications. There are three PEG techniques. The pull/push and introducer methods have been established as standard techniques for PEG tube placement. The modified introducer method, namely the direct method, allows for direct placement of a larger button-bumper-type catheter device. PEG tube placement using the introducer method or the direct method may be a much safer alternative than the pull/push method. PEG may be recommended in patients with aerodigestive cancer because of the improved complication rate. 展开更多
关键词 Aerodigestive CanCER PERCUTanEOUS endoscopic GASTROStoMY Direct METHOD introducer METHOD Pull/push METHOD Complications
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Treating ballast water with hydroxyl radical on introduced organisms 被引量:3
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作者 张芝涛 白敏菂 +3 位作者 肖宇 白敏冬 杨波 白希尧 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第2期161-167,共7页
With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl... With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%-4% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system. 展开更多
关键词 hydroxyl radical introduced organisms photosynthesis pigment lipid peroxidation basic life substances antioxidant enzyme ballast water
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Small-scale dipolarization fronts in the Earth’s magnetotail 被引量:1
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作者 Jing Huang Meng Zhou +3 位作者 HuiMin Li XiaoHua Deng Jiang Liu ShiYong Huang 《Earth and Planetary Physics》 CSCD 2019年第4期358-364,共7页
Previous studies suggest that dipolarization fronts (DFs) are 1 to 3RE (RE is the earth radius) wide in the dawn-dusk direction. Recent kinetic simulations have found that DFs may break up into small-scale structures ... Previous studies suggest that dipolarization fronts (DFs) are 1 to 3RE (RE is the earth radius) wide in the dawn-dusk direction. Recent kinetic simulations have found that DFs may break up into small-scale structures after they are produced by reconnection. Motivated by this simulation, we revisited the scale size of DFs in the dawn-dusk direction by using Cluster observations during the years when the inter-distance among Cluster spacecraft was between 1000 and 2000 km. We selected the DFs that were detected by more than one spacecraft and estimated the radii of these DFs by a simple geometrical analysis, which is based on comparison of DF normals observed by different spacecraft. We found a few DFs that were only a few ion inertial lengths in the dawn-dusk direction. These results point out the importance of multi-scale coupling during the evolution of DFs. 展开更多
关键词 DIPOLARIZATION FRONT small SCALE earth's MAGNEtoTAIL
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The Akp-Btk value method and the resultsfor the retrieval of the parameters of the Earth's free core nutation 被引量:1
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作者 雷湘鄂 贾民育 李辉 《Acta Seismologica Sinica(English Edition)》 CSCD 2000年第3期342-350,358,共10页
The rotation of the Earth's liquid core creates the Nearly Diurnal Free Wobble (NDFW). It is one of the problems of researching the Earth's liquid core for us to retrieve the parameters of the Earth's Free... The rotation of the Earth's liquid core creates the Nearly Diurnal Free Wobble (NDFW). It is one of the problems of researching the Earth's liquid core for us to retrieve the parameters of the Earth's Free Core Nutation (FCN),from the Earth's liquid core resonance of gravity tide waves on the diurnal frequency band. Since 1987, some scientists in many different countries have come to calculate the parameters of FCN by using the observational data of gravity tide waves on the diumal frequency band. They basically followed the Stacking method, which needed five diurnal waves for the resolution. In this paper, authors introduced the Aky-Btk value method with clearly geometrical meaning as a new method, which only requires three very high signal-noise-ratio waves o1, K1 and P1 for the resolution. Authors chose the observational data of the three superconducting gravimeter stations respectively located in Cantley of Canada, Wuhan of China and Brussels of Belgium, to compute the parameters of FCN. It was the first time that the observational results of the parameters of FCN obtained from gravitational tide were in accord with the parameters of FCN gained from VLBI since 1987. 展开更多
关键词 earth's liquid core resonance of gravity tide (LCR) parameters of earth's free core nutation triangle of LCR Akp-Btk value method
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