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Evaluation of red soil-bentonite mixtures for compacted clay liners
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作者 A.S.Devapriya T.Thyagaraj 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期697-710,共14页
Compacted clay liners are an integral part of the waste landfills,which are provided to contain the leachate within the landfills and protect the surrounding environment.Generally,locally available natural soils are u... Compacted clay liners are an integral part of the waste landfills,which are provided to contain the leachate within the landfills and protect the surrounding environment.Generally,locally available natural soils are used for the construction of compacted clay liners if they satisfy the design criteria.However,not all soils in their natural state satisfy all the design criteria for the liner materials.Thus,there is a definite need to modify the locally available natural soils by blending with bentonite to meet the required design criteria for the liners.In view of this,the present study evaluates the suitability of an Indian red soil enhanced with bentonite as a liner material.To achieve this,a series of experiments were carried out using locally available red soil and bentonite.First,the suitability of the red soil was evaluated as a liner material.The experimental results showed that the red soil met all the selection criteria stipulated by the Environmental Protection Agencies(EPAs)for the liners except the hydraulic conductivity criterion.Therefore,the red soil was mixed with bentonite contents of 10%,20%and 30%,and the red soil-bentonite mixtures were evaluated for their suitability for liners in their compacted state.Further,as the liners in the arid and semi-arid regions are subjected to moisture variations due to seasonal moisture fluctuations and other factors,the red soil-bentonite mixtures were subjected to wetdry cycles,and their suitability was evaluated after wet-dry cycles.The experimental results revealed that all the red soil-bentonite mixtures met the stipulated EPA criteria for the liners in the as-compacted state.However,the red soil-bentonite mixtures with 20%and 30%bentonite contents only satisfied the hydraulic conductivity requirement even after wet-dry cycles.The experimental findings were supplemented with the microstructural insights captured through digital camera images,scanning electron microscopy(SEM),and mercury intrusion porosimetry(MIP)studies. 展开更多
关键词 Compacted clay lines Hydraulic conductivity Wet-dry cycles Microstructure
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Evolution Mechanism of a Severe Squall Line Triggered by the Coupling of a Sea Breeze Front and a Gust Front
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作者 万夫敬 孙敏 +2 位作者 庞华基 赵海军 赵传湖 《Journal of Tropical Meteorology》 SCIE 2024年第2期200-210,共11页
In the present study, a severe squall line(SL) was analyzed by using intensive observational surface data and radar monitoring products. In this process, mesoscale convergence lines, such as the sea breeze front(SBF),... In the present study, a severe squall line(SL) was analyzed by using intensive observational surface data and radar monitoring products. In this process, mesoscale convergence lines, such as the sea breeze front(SBF), gust front and dry line, served as the main triggering and strengthening factors. The transition from convection triggering to the formation of the initial shape was mainly affected by the convergence line of the SBF, which combined with thermal convection to form the main parts of the SL. In the later stage, the convergence line of the gust front merged with other convergence lines to form a series of strong convective cells. The SBF had good indicative significance in terms of severe convective weather warnings. The suitable conditions of heat, water vapor and vertical wind shear on the Shandong Peninsula were beneficial to the maintenance of the SL. Before SL occurrence, tropopause folding strengthened, which consequently enhanced the baroclinic property in the middle and upper troposphere. The high sensible heat flux at the surface easily produced a positive potential vorticity anomaly in the low layer, resulting in convective instability, which was conducive to the maintenance of these processes. In the system, when precipitation particles passed through the unsaturated air layer, they underwent strong evaporation, melting or sublimation, and the cooling effect formed negative buoyancy, which accelerated the sinking of the air and promoted the sustained development of the surface gale. Together with the development of lowlevel mesocyclones, the air pressure decreased rapidly, which was conducive to gale initiation. 展开更多
关键词 squall line sea breeze front gust front cold pool thunderstorm gale
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Research on Total Electric Field Prediction Method of Ultra-High Voltage Direct Current Transmission Line Based on Stacking Algorithm
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作者 Yinkong Wei Mucong Wu +3 位作者 Wei Wei Paulo R.F.Rocha Ziyi Cheng Weifang Yao 《Computer Systems Science & Engineering》 2024年第3期723-738,共16页
Ultra-high voltage(UHV)transmission lines are an important part of China’s power grid and are often surrounded by a complex electromagnetic environment.The ground total electric field is considered a main electromagn... Ultra-high voltage(UHV)transmission lines are an important part of China’s power grid and are often surrounded by a complex electromagnetic environment.The ground total electric field is considered a main electromagnetic environment indicator of UHV transmission lines and is currently employed for reliable long-term operation of the power grid.Yet,the accurate prediction of the ground total electric field remains a technical challenge.In this work,we collected the total electric field data from the Ningdong-Zhejiang±800 kV UHVDC transmission project,as of the Ling Shao line,and perform an outlier analysis of the total electric field data.We show that the Local Outlier Factor(LOF)elimination algorithm has a small average difference and overcomes the performance of Density-Based Spatial Clustering of Applications with Noise(DBSCAN)and Isolated Forest elimination algorithms.Moreover,the Stacking algorithm has been found to have superior prediction accuracy than a variety of similar prediction algorithms,including the traditional finite element.The low prediction error of the Stacking algorithm highlights the superior ability to accurately forecast the ground total electric field of UHVDC transmission lines. 展开更多
关键词 DC transmission line total electric field effective data multivariable outliers LOF algorithm Stacking algorithm
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Value and Measures of Integrating Local Red Culture into the Ideological and Political Course of Environmental Disciplines under the OBE Concept
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作者 Xiong YAN Wenzhao LI +5 位作者 Shenwen CAI Bailian XIONG Liumei CHEN Junwei CHENG Qinghe WANG Leilei FAN 《Asian Agricultural Research》 2024年第2期40-42,共3页
Based on output-oriented education,the OBE(Outcome-Based Education)concept integrates local red culture into the ideological and political course of environmental disciplines,and is an important part of training appli... Based on output-oriented education,the OBE(Outcome-Based Education)concept integrates local red culture into the ideological and political course of environmental disciplines,and is an important part of training applied talents of environmental disciplines in the new era.This educational model makes an innovation on the traditional educational and teaching concepts and centers on students.This paper analyzes the value of integrating local red culture into the ideological and political course under the OBE concept,and puts forward an effective implementation path. 展开更多
关键词 OBE(Outcome-Based Education)concept Local red culture Environmental disciplines Ieological and political course
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Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy
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作者 Xian-Rang Cao Yin-Long Xu +4 位作者 Jia-Wei Chai Kai Zheng Jun-Jie Kong Jun Liu Shun-Zhen Zheng 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期143-157,共15页
BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopi... BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopic pancreatoduodenectomy(LPD).METHODS A total of 804 consecutive patients who underwent LPD at our hospital between March 2017 and November 2021 were retrospectively analyzed.Correlations between pretreatment RDW and clinicopathological characteristics and short-term outcomes were investigated.RESULTS Patients with higher pretreatment RDW were older,had higher Eastern Cooperative Oncology Group scores and were associated with poorer short-term outcomes than those with normal RDW.High pretreatment RDW was an independent risk factor for postoperative complications(POCs)(hazard ratio=2.973,95%confidence interval:2.032-4.350,P<0.001)and severe POCs of grade IIIa or higher(hazard ratio=3.138,95%confidence interval:2.042-4.824,P<0.001)based on the Clavien-Dino classification system.Subgroup analysis showed that high pretreatment RDW was an independent risk factor for Clavien-Dino classi-fication grade IIIb or higher POCs,a comprehensive complication index score≥26.2,severe postoperative pancreatic fistula,severe bile leakage and severe hemorrhage.High pretreatment RDW was positively associated with the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio and was negatively associated with albumin and the prognostic nutritional index.CONCLUSION Pretreatment RDW was a special parameter for patients who underwent LPD.It was associated with malnutrition,severe inflammatory status and poorer short-term outcomes.RDW could be a surrogate marker for nutritional and inflammatory status in identifying patients who were at high risk of developing POCs after LPD. 展开更多
关键词 BIOMARKER Laparoscopic pancreatoduodenectomy Postoperative complication red blood cell distribution width Short-term outcomes
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Incorporating red blanket protocol within code crimson:Streamlining definitive trauma care amid the chaos
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作者 Sohil Pothiawala Savitha Bhagvan Andrew MacCormick 《World Journal of Critical Care Medicine》 2025年第1期14-19,共6页
The care of a patient involved in major trauma with exsanguinating haemorrhage is time-critical to achieve definitive haemorrhage control,and it requires coordinated multidisciplinary care.During initial resuscitation... The care of a patient involved in major trauma with exsanguinating haemorrhage is time-critical to achieve definitive haemorrhage control,and it requires coordinated multidisciplinary care.During initial resuscitation of a patient in the emergency department(ED),Code Crimson activation facilitates rapid decisionmaking by multi-disciplinary specialists for definitive haemorrhage control in operating theatre(OT)and/or interventional radiology(IR)suite.Once this decision has been made,there may still be various factors that lead to delay in transporting the patient from ED to OT/IR.Red Blanket protocol identifies and addresses these factors and processes which cause delay,and aims to facilitate rapid and safe transport of the haemodynamically unstable patient from ED to OT,while minimizing delay in resuscitation during the transfer.The two processes,Code Crimson and Red Blanket,complement each other.It would be ideal to merge the two processes into a single protocol rather than having two separate workflows.Introducing these quality improvement strategies and coor-dinated processes within the trauma framework of the hospitals/healthcare systems will help in further improving the multi-disciplinary care for the complex trauma patients requiring rapid and definitive haemorrhage control. 展开更多
关键词 red blanket protocol Code crimson HAEMORRHAGE Trauma
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Cluster Analysis of Chinese Pumpkin Inbred Lines 被引量:7
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作者 杜晓华 李小梅 李新峥 《Agricultural Science & Technology》 CAS 2008年第4期104-107,共4页
A cluster analysis was carried out based on Euclidean genetic distances through UPGMA method in Chinese pumpkin inbred lines.7 important agronomic traits of 46 Chinese pumpkin inbred lines were investigated.The result... A cluster analysis was carried out based on Euclidean genetic distances through UPGMA method in Chinese pumpkin inbred lines.7 important agronomic traits of 46 Chinese pumpkin inbred lines were investigated.The result indicated that 46 pumpkin inbred lines were clustered into 4 groups and the inter-groups distances was larger than that in intra-group.The genetic distances of parents were related to F1 performance and the results of cluster would increase effectiveness in the Chinese pumpkin crossing breeding. 展开更多
关键词 CHINESE PUMPKIN INBred lineS CLUSTER
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Analysis on Combining Ability and Genetic Parameters of Main Agronomic Characters of 22 Maize Inbred Lines
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作者 张亚勤 邱正高 +5 位作者 杨华 祁志云 汤玲 李淑君 张丕辉 袁亮 《Agricultural Science & Technology》 CAS 2015年第9期1907-1911,1915,共6页
The general combining ability(GCA), special combining ability(SCA) and genetic parameter of ten characters of 22 maize inbred lines including plant height and ear height were analyzed using 10×12 through inco... The general combining ability(GCA), special combining ability(SCA) and genetic parameter of ten characters of 22 maize inbred lines including plant height and ear height were analyzed using 10×12 through incomplete diallel cross(NC Ⅱ).The results showed that:(1) Among the 22 maize inbred lines, the yield GCAs of11 HN 097, 11 HN 099, 11 HN 105 and 11 HN 110 were high, which were elite inbred lines to collocate hybridized combinations with strong heterosis. The yield of11 HN110 × 11 HN097, 11 HN110 × 11 HN105, 11 HN112 × 11 HN 097 and 11 HN 106 × 11 HN 104 were in the first four place. The yielding abilities, adaptabilities and yielding stabilities of the four combinations can be further identified by experiment. The heredities of the ten characters were mainly controlled by additive gene effect whereas the influence of non-addictive gene effect was small. The narrow heritabilities of plant height, ear height, ear rows, ear length, kernels per row,100-grain weight and seed-producing percentage were more than 50%. The variances were mainly caused by heredity and early-generation selection should be conducted. The narrow heritabilities of ear diameter, bare tip length and yield was low, which should not be selected in early-generation. 展开更多
关键词 MAIZE Inbred line Combining ability Genetic parameter
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Combining Ability and Correlation of Ear Characteristics of Twenty Maize Inbred Lines
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作者 李淑君 董昕 +3 位作者 付忠军 祁志云 张丕辉 周汝平 《Agricultural Science & Technology》 CAS 2017年第9期1601-1606,共6页
The combining ability and correlation of eight ear characteristics in 99 maize hybrids generated by crossing nine female parents with 11 male parents were analyzed by incomplete diallel cross (NC II ) design. The re... The combining ability and correlation of eight ear characteristics in 99 maize hybrids generated by crossing nine female parents with 11 male parents were analyzed by incomplete diallel cross (NC II ) design. The results showed that the line F6 had the highest general combining ability (GCA) for yield, followed by F7, M3, M4 and M8. All of the five lines have great potential in maize breeding. The cross combination M3xF10 had the highest specific combining ability (SCA) for yield, showing strong heterosis. Heritability analysis of ear characteristics showed that GCA variance was higher than SCA variance in ear diameter, number of rows per ear and seed rate, and they were mainly controlled by the additive gene effect, indicating that that the selections for these traits are effective at early generations. The other three traits had lower SCA, for which the selections should be carried out at late generations. The correlation analysis revealed that ear length, number of grains per row, ear diameter, number of rows per ear, 100-seed weight and seed rate had extremely significant positive correlations with grain yield per plant. Among them, number of grains per row had the most significant effect on yield per plant. Barren tip length had a significant negative correlation with grain yield per plant. Therefore, we concluded that the combinations with more grains per row and shorter barren tip should be selected to achieve high yield of maize. 展开更多
关键词 MAIZE Inbred line Combining ability Ear characteristics Genetic parameters
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Combining Ability Analysis on Yield Traits of Recombinant Inbred Lines in Hybrid Rice
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作者 曹应江 游书梅 +8 位作者 郑家奎 蒋开锋 张涛 杨莉 杨乾华 万先齐 罗婧 李昭祥 高磊 《Agricultural Science & Technology》 CAS 2015年第9期1877-1882,共6页
A population of 140 recombinant inbred lines at F8 generation were obtained after seven successive generations of self-pollination using single seed descent(SSD) method from the F2 hybrids of three-line restorers Lu... A population of 140 recombinant inbred lines at F8 generation were obtained after seven successive generations of self-pollination using single seed descent(SSD) method from the F2 hybrids of three-line restorers Luhui 8258 with high combining ability and Yanghui 34. Then, the 140 inbred lines obtained above and their parents Luhui 8258 and Yanghui 34 were crossed with three different types of cyto-plasmic male sterile(CMS) lines(Gang 46 A, Ⅱ-32 A and Lu 98A) according to NCⅡ design. The resulting 426 combinations were planted at Deyang and Suining bases to test the combining ability and inheritance of five yield traits: yield per plant, panicle number per plant, filled grain number per panicle, seed setting rate and 1 000-grain weight. The results showed that the variances of both general and specific combining abilities of the five traits all reached a significant or extremely significant level at the two sites. The broad and narrow heritability of the yield traits(except 1 000-grain weight whose broad and narrow heritability were both over70%) were all below 50% at the two experimental bases, suggesting that the four traits were easily subjected to environment influence. Very significant positive correlation of general combining ability was found between yield per plant and other traits except 1 000-grain weight. The general combining ability variance showed a normal distribution among the recombinant inbred lines at two sites, right in line with inheritance of quantitative traits. So, the genes controlling rice general combining ability can be targeted by QTL mapping. 展开更多
关键词 Hybrid rice Recombinant inbred lines Yield traits Combining ability
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Combining Ability Analysis of Panicle Traits in Six CIMMYT Maize Inbred Lines
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作者 付忠军 李淑君 +2 位作者 董昕 祁志云 张丕辉 《Agricultural Science & Technology》 CAS 2015年第12期2653-2655,2663,共4页
In this study, six CIMMYT maize inbred lines and five representative do- mestic maize inbred lines were used as parental lines. By using incomplete diallel cross design, 30 hybrid combinations were developed to analyz... In this study, six CIMMYT maize inbred lines and five representative do- mestic maize inbred lines were used as parental lines. By using incomplete diallel cross design, 30 hybrid combinations were developed to analyze the general com- bining ability (GCA), specific combining ability (SCA) and total combining ability (TCA) of seven panicle traits in six CIMMYT maize inbred lines. The results showed that CIMBL98 and GEMS13 were excellent inbred lines with good compre- hensive performance; CIMBL98 × 340 and GEMS13×Chang 7-2 were superior combinations. 展开更多
关键词 Maize (Zea mays L.) Inbred line Panicle traits Combining ability
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Mapping of QTLs for Sheath Blight Resistance Using Recombinant Inbred Lines of Rice(Oryza sativa L.)
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作者 杨娟 王莉娟 +1 位作者 黄胜东 李余生 《Agricultural Science & Technology》 CAS 2015年第7期1374-1377,共4页
A recombinant inbred line (RIL) population composed of 157 lines derived from an inter-subspecific hybrid of Daguandao/IR28 by the single seed descent method was used as materials, and the quantitative trait loci (... A recombinant inbred line (RIL) population composed of 157 lines derived from an inter-subspecific hybrid of Daguandao/IR28 by the single seed descent method was used as materials, and the quantitative trait loci (QTLs) coffering the resistance to sheath blight in the 157 RILs and the parents were detected using the toothpick inoculation method. The disease indexes of rice sheath blight in the two parents and 157 RILs were scored and the QTLs responsible for rice sheath blight resistance were detected accordingly by QTL Cartographer software. The results showed that a total of 4 QTLs (qsbl, qsb2, qsb5-1, qsb5-2) conferring sheath blight resistance were detected on chromosomes 1, 2 and 5, and their variance explained ranged from 10.41% to 36.92%. The additive effect of qsb5-1 was negative, indicat- ing that the QTLs derived from donor parent IR 28 could enhance the resistance to sheath blight. However, the additive effects of qsbl, qsb2 and qsb5-2 were positive, indicating that the QTLs derived from donor parent Daguandao weakened the resis- tance to sheath blight. 展开更多
关键词 Sheath blight resistance Recombinant inbred lines Quantitative trait locus
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Selection of Maize Inbred Lines with High Regeneration and Susceptibility to Agrobacterium tumifacien 被引量:3
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作者 王钰 付绍红 +5 位作者 文颖 张志明 夏燕莉 刘玉贞 荣廷昭 潘光堂 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期749-755,共7页
Ten-maize inbred lines of maize (Zea mays L.) with high-induction rate and proliferation ability of embryonic calli were selected from 70-maize inbred lines by immature embryo culturing. Some of the embryonic calli ... Ten-maize inbred lines of maize (Zea mays L.) with high-induction rate and proliferation ability of embryonic calli were selected from 70-maize inbred lines by immature embryo culturing. Some of the embryonic calli were transferred onto regeneration medium to examine the ability of regeneration, some were transformed via Agrobacterium tumifaciens C58 carrying intron-β-glucuronidase (gus) gene, and GV3301 carrying the green fluorescent protein (gfp) gene to study the susceptibility of different genotypes in maize to A. tumifaciens. All embryonic calli initiated from 10-maize inbred lines were able to regenerate into plantlets, and the regeneration frequencies of inbred lines 6010, 6038, 6015, 6051, and 6060 were 61.11%, 31.94%, 45%, 33.33%, and 56.94%, respectively, which were higher than that of other lines. Analysis of variance indicated that the susceptibility of the various genotypes in maize to A. tumifacien C58 showed a significant difference among each other, and the inbred lines 6010, 6015, 6051, 6050, 6058, 6060, 6069, 6077 were susceptible to A. tumifacien C58, of which frequency of gus expression were over 70%. Expression of GFP was observed in six-inbred lines (6050, 6015, 6051, 6058, 6069, 6077). The inbred lines 6051, 6010, 6015, 6060, and 6050 had the high regeneration and the susceptibility to A. tumifaciens C58; and the inbred lines 6051, 6015, and 6060 had the high regeneration and the susceptibility to Agrobacterium tumifaciens GV3301. 展开更多
关键词 maize inbred lines embryogenic calli Agrobacterium tumifacien GFP GUS
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The Predictability of a Squall Line in South China on 23 April 2007 被引量:8
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作者 吴多常 孟智勇 严大春 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第2期485-502,共18页
This study investigated the predictability of a squall line associated with a quasi-stationary front on 23 April 2007 in South China through deterministic and probabilistic forecasts. Our results show that the squalll... This study investigated the predictability of a squall line associated with a quasi-stationary front on 23 April 2007 in South China through deterministic and probabilistic forecasts. Our results show that the squallline simulation was very sensitive to model error from horizontal resolution and uncertainties in physical parameterization schemes. At least a 10-km grid size was necessary to decently capture this squall line. The simulated squall line with a grid size of 4.5 km was most sensitive to long-wave radiation parameterization schemes relative to other physical schemes such as microphysics and planetary boundary layer. For a grid size from 20 to 5 km, a cumulus parameterization scheme degraded the squall-line simulation (relative to turning it off), with a more severe degradation to grid size -10 km than 〉10 km. The sensitivity of the squall-line simulation to initial error was investigated through ensemble forecast. The performance of the ensemble simulation of the squall line was very sensitive to the initial error. Approximately 15% of the ensemble members decently captured the evolution of the squall line, 25% failed, and 60% dislocated the squall line. Using different combinations of physical parameterization schemes for different members can improve the probabilistic forecast. The lead time of this case was only a few hours. Error growth was clearly associated with moist convection development. A linear improvement in the performance of the squall line simulation was observed when the initial error was decreased gradually, with the largest contribution from initial moisture field. 展开更多
关键词 squall line PredICTABILITY South China ENSEMBLE MOISTURE
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Genetic Relation Analysis on Ramie[Boehmeria nivea(L.)Gaud.]Inbred Lines by SRAP Markers 被引量:15
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作者 LIU Li-jun PENG Ding-xiang WANG Bo 《Agricultural Sciences in China》 CAS CSCD 2008年第8期944-949,共6页
The objective of this article is to reveal the variations of ramie inbred lines in DNA level and discuss their molecular background to provide a theoretical basis for ramie cross breeding. In the present study, the ge... The objective of this article is to reveal the variations of ramie inbred lines in DNA level and discuss their molecular background to provide a theoretical basis for ramie cross breeding. In the present study, the genetic relationships among 33 inbred line accessions and two wild types that originated from China and Brazil were estimated using sequence-related amplified polymorphism (SRAP) markers. The results showed that 33 out of 81 primer combinations turned out to be polymorphic and 332 polymorphism bands were obtained. On the basis of the appearance of the markers, the genetic relationships were analyzed using unweighted pair-group method of arithmetic average cluster analysis (UPGMA), and the genetic Jaccard similarity coefficients were calculated. The inbred-lines originating from China and Brazil formed a cluster suggesting a possibility that the Brazilian cultivars could have developed from cultivars introduced from China. Within ramie inbred-lines, the groupings also indicated that the greatest genetic relationship among cultivars was correlated to the region of origin of cultivars. The results provided the evidence that SRAP was an efficient approach, suitable for taxonomic analysis of ramie inbred lines, To the authors' knowledge, this is the first application of SRAP marker on the systematics of ramie inbred lines. 展开更多
关键词 relatives of ramie inbred lines SRAP taxonomic analysis UPGMA
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CHARACTERISTICS ANALYSIS OF THE INDUCED OVERCURRENT GENERATED BY CLOSE TRIGGERED LIGHTNING ON THE OVERHEAD TRANSMISSION POWER LINE 被引量:8
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作者 杨少杰 陈绍东 +5 位作者 张义军 董万胜 王建国 周蜜 王孝波 余晖 《Journal of Tropical Meteorology》 SCIE 2010年第1期59-65,共7页
Techniques of artificially-triggered lightning have provided a significantly useful means to directly measure various physical parameters of lightning discharge and to conduct research on protection methods of lightni... Techniques of artificially-triggered lightning have provided a significantly useful means to directly measure various physical parameters of lightning discharge and to conduct research on protection methods of lightning electromagnetic pulses.In this study,using capacitive and resistive dividers,current probes and optical fiber transmission devices,we measured and analyzed the induced overvoltage on the overhead transmission line and the overcurrent through Surge Protective Devices(SPD) when a lightning discharge was artificially triggered nearby on August 12,2008 at Conghua Field Lightning Experiment Site.The triggered lightning discharge contained an initial current stage and eight return strokes whose peak currents ranged from 6.6kA to 26.4kA.We found that overcurrents through SPD were induced on the power line both during the initial continuous current stage and the return stroke processes.During the return strokes,the residual voltage and the current through the SPD lasted up to the ms(millisecond) range,and the overcurrents exhibited a mean waveform up to 22/69μs with a peak value of less than 2kA.Based on the observed data,simple calculations show that the corresponding single discharge energy was much greater than the values of the high voltage pulse generators commonly used in the experiments regulated for SPD.The SPD discharge current peak was not synchronous to that of the residual voltage with the former obviously lagging behind the latter.The SPD discharge current peak was well correlated with the triggered lightning current peak and the wave-front current gradient.The long duration of the SPD current is one of the major reasons why the SPD was damaged even with a big nominal discharge current. 展开更多
关键词 triggered lightning overhead transmission line SPD induced overcurrent
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Comparison of Remolded Shear Strength with Intrinsic Strength Line for Dredged Deposits 被引量:9
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作者 邓东升 《China Ocean Engineering》 SCIE EI 2007年第2期363-369,共7页
Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on th... Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on the intrinsic strength line is different from the remolded undrained shear strength that is an important parameter for design and construction of land reclamation. The void index is used in this study for normalizing the remolded strength behavior of dredged deposits. A quantitative relationship between remolded undrained shear strength and void index is established based on extensive data of dredged deposits available from sources of literature. Furthermore, the normalized remolded undrained shear strength is compared with intrinsic strength line. The comparison result indicates that the ratio of undrained shear strength on the intrinsic strength line over remolded undrained shear strength increases with an increase in applied consolidated stress. 展开更多
关键词 consolidation stress dredged deposits intrinsic strength line remolded shear strength void index
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Defensive physiological characters of Pyropia yezoensis resistant lines to the red rot disease 被引量:2
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作者 ZOU Dandan TANG Xianghai +1 位作者 QIU Liping MAO Yunxiang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第2期509-516,共8页
To explore ef fective physiological indexes to distinguish the resistant lines and susceptible lines of Pyt hium porphyrae,the causal agent of red rot disease of Pyropia yezoensis,and establish the disease-resistance ... To explore ef fective physiological indexes to distinguish the resistant lines and susceptible lines of Pyt hium porphyrae,the causal agent of red rot disease of Pyropia yezoensis,and establish the disease-resistance breeding strategy,we obtained and analyzed the candidate resistant and susceptible lines by population selection.Gametophytes of the candidate lines were cultured in seawater containing Pyt.porphyrae zoospores.Antioxidase activities,including superoxide dismutase(SOD),peroxidase(POD)and polyphenol oxidase(PPO),were measured and compared between the two lines before and after infection.In the resistant lines,SOD and POD activities increased and then decreased,but PPO activity rose with the prolongation of the infection time.The phenylalanine ammonia lyase(PAL)activities also increased and then decreased after infection,but it had significantly different expression in the two lines without pathogen attack.The synthesis rates ofβ-1,3-glucanase,and cell-wall degrading enzyme were different from each other between the two lines after infection of P yt.porphyrae.Comparison in the contents of malondialdehyde(MDA)and reactive oxygen species(ROS)in the two lines showed that,the two contents varied synchronously in response to the pathogen attack.Changes of these enzymes activities or contents demonstrated that Pyr.yezoensis could resist against the pathogen of P yt.porphyrae with the antioxidant defense capacity.In addition,β-1.3-glucanase content showed extremely significant dif ference between the two lines,and the PAL had consistent expression dif ference.Therefore,phenylalanine ammonia lyase(PAL)andβ-1,3-glucanase can be considered as an ef fective index to distinguish susceptible line and resistant line,with which the workload of the resistant breeding could be reduced in the future. 展开更多
关键词 population selection resistant lines susceptible lines P yropia yezoensis Pythium porphyrae
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Establishment of Embryonic Stem Cell Lines Derived from Outbred Mouse Embryos and Production of Chimeras 被引量:2
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作者 何维 高建刚 +1 位作者 刘晓 孙方臻 《Developmental and Reproductive Biology》 1996年第2期21-25,共5页
The aim of the present investigation was to determine if embryonic stem (ES) cells could be isolated from outbred mouse embryos (KM) and if chimeras could be producedly using outbred ES cells. Three ES cell lines,desi... The aim of the present investigation was to determine if embryonic stem (ES) cells could be isolated from outbred mouse embryos (KM) and if chimeras could be producedly using outbred ES cells. Three ES cell lines,designated KE1, KE2, and KE5,were isolated from 5 Kunming albino blastocysts. Normal diploid composition of these cell lines was above 70%. By using C57BL/6J and 615 blastocysts as host embryos, one chimera was obtained in living pups. It was shown for the first time that chimeras can be produced by using outhred ES cells. This work implies that to establish ES cell lines from other animal embryos is possible. More interestingly, white color dots from ES cells on the coat of this chimeric mouse enlarged a lot after half a year, indicated that ES cells were inhibited by cells from outbred mouse or the cells of outbred mouse grew vigiously. 展开更多
关键词 KM mouse blastocyst ES cell line chimeric mice.
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Development of Chromosomal Segment Substitution Lines from a Backcross Recombinant Inbred Population of Interspecific Rice Cross 被引量:4
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作者 CHEN Jie Hafeez Ur Rahman BUGHIO +3 位作者 CHEN Da-zhou LIU Guang-jie ZHENG Kang-le ZHUANG Jie-yun 《Rice science》 SCIE 2006年第1期15-21,共7页
A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper res... A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression. 展开更多
关键词 alien introgression DNA marker Dongxiang wild rice chromosomal segment substitution line
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