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variation in seed morphometric characters, oil content and azadirachtin content of seeds, in vitro shoot cultures and callus cultures among different populations of Azadirachta indica

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Journal of Forestry Research 2018年第1期29卷 121-127页

作者： Fatima Shirin Anamika Rai Neelu Singh Genetics and Plant Propagation Division Tropical Forest Research Institute PO RFRC Non-Wood Forest Produce Division Tropical Forest Research Institute PO RFRC

We studied seed morphometric characters, oil content and azadirachtin content in a medicinally important and insect repellent tree species Azadirachta indica ***. Ten populations were selected from two central Indian states of Madhya Pradesh and Chhattisgarh and twenty candidate plus trees were selected from each population based on tree attributes. Azadirachtin content was estimated in seeds, in vitro shoots and callus cultures through HPLC. Significant variation（p ／ 0.05） was observed in seed morphometric characters, oil content and azadirachtin content among the ten populations. Maximum value for 100 seed weight was obtained in seeds of Raigarh（30.51 g） which was on par with seeds of Bargi（28.37 g）and Chhatarpur（26.36 g）. The ratio of highest kernel to seed was also obtained in seeds of Raigarh（60.11%）.Kernels from Chhatarpur population recorded the highest oil content（24.20%）, which was equal to that in Sihore（23.75%） and Katni（21.75%）. We recorded highly significant variation in azadirachtin content in seed samples,in vitro shoot samples and callus cultures. Maximum azadirachtin was present in the seeds of Gwalior（0.882%）which was on par with azadirachtin content in seeds of Chhatarpur, Katni, Sihore, Shahdol and *** azadirachtin in the in vitro shoots was present in the cultures of Gwalior（0.218%） which was statistically on par with Sihore（0.176%）. Similarly, in callus cultures of nodal segments maximum azadirachtin was recorded in the Gwalior population（0.033%） which was statistically on par with Sihore（0.028%）. The trees of Gwalior and Sihore populations can be produced in large numbers through vegetative propagation to obtain seeds with higher azadirachtin content.

关键词： Azadirachtin In vitro Seed morphometric characters Populations variation

variation in allelic frequencies at loci associated with kernel weight and their effects on kernel weight-related traits in winter wheat

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The Crop Journal 2019年第1期7卷 30-37页

作者： Teng Li Hongwei Liu Chunyan Mai Guangjun Yu Huili Li Lingzhi Meng Dawei Jian Li Yang Yang Zhou Hongjun Zhang Hongjie Li National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop Sciences Chinese Academy of Agricultural Sciences Xinxiang Innovation Center for Breeding Technology of Dwarf-Male-Sterile Wheat Zhaoxian Experiment Station Shijiazhuang Academy of Agricultural and Forestry Sciences Institute of Agricultural Science The Fourth Division of the Xinjiang Production and Construction Corps

Knowledge of allelic frequencies at loci associated with kernel weight and effects on kernel weight-related traits is crucial for yield improvement in wheat. Kernel weight-related traits were evaluated in 200 Chinese winter wheat cultivars(lines) grown at the Xinxiang Experimental Station, Chinese Academy of Agricultural Sciences, Xinxiang in Henan Province, for three consecutive years from 2014 to 2016. Alleles associated with kernel weight at nine loci, TaCKX6-D1, TaCwi-A1, TaCWI-4A, TaGS1a, TaGS5-A1, TaGS3-3A, TaGW2-6A, TaSus2-2B, and TaTGW6-A1, were determined for all cultivars(lines). ANOVA showed that genotypes, years and their interactions had significant effects on thousand-kernel weight(TKW), kernel length(KL) and kernel width(KW). The overall mean frequencies of alleles conferring high and low TKW at the nine loci were 65.9% and 33.4%, with the ranges of 37.0%–85.0% and 13.5%–63.0% for single loci. The frequencies of high-TKW alleles were over 50.0% at eight of the loci. Genotypes at each locus with the high-TKW allele had higher TKW than those with the low-TKW allele. The high-TKW allele Hap-H at the TaSus2-2B locus can be preferably used to increase grain yield due to its high TKW(49.32 g). A total of 18 main allelic combinations(ACs) at nine loci were detected. Three ACs(AC1–AC3) had significantly higher TKW than AC6 with high-TKW alleles at all nine loci even though they contained some low-TKW alleles. This indicated that other loci controlling kernel weight were present in the high-TKW cultivars. This work provides important information for parental selection and marker-assisted selection for breeding.

关键词： Allelic frequency Allelic variation Functional markers Triticum aestivum

variation analysis of growth traits of four poplar clones under different water and fertilizer management

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Journal of Forestry Research 2020年第1期31卷 45-55页

作者： Ammar Khalil Mohamed Ahmed Luping Jiang Fang Wang Song Chen Xueyan Zhou Xiaona Pei Xiyang Zhao Guanzheng Qu State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Faculty of Forest Science and Technology University of Gezira22212 MadaniAbu HarazSudan

To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,and potassium fertilizers),each with four levels,using an orthogonal experimental design.A logistic model was used to estimate growth in *** growth curves for tree height were sigmoid,and the model R^2 values were greater than 0.9,which indicated that the fit was highly *** results for tree height and basal diameter indicated that all sources of variance showed significant differences(p<0.001).The average tree height and basal diameter for all the four clones under the different treatments ranged from 155.39 to 235.04 cm,and from 13.71 to 17.42 mm,respectively.A highly positive correlation between the extreme k value and tree height was observed,suggesting that the k value was an accurate estimation of tree *** model parameters,the earliest average time point for the onset of the rapid growth period of poplar clones was 131 d,and the highest average increment in tree height during the rapid growth period was 138.78 *** highest average tree height for all clones under each factor was 219,210.51,200,and 201 cm when treated with either 1200 mL of water applied every third day,3 g of nitrogen,0 g of phosphorus,or 0 g of potassium,*** most suitable treatment for the early growth of hybrid poplar cuttings,as suggested by the developed logistic model,was 1200 mL of water applied every third day and three applications of 1 g nitrogen(in the form of CH4N2O).

关键词： Fertilizer management Growth trait Logistic model Poplar Rapid growth variation

variation and dispersal of PM_(10) and PM_(2.5) during COVID-19 lockdown over Kolkata metropolitan city,India investigated through HYSPLIT model

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Geoscience Frontiers 2022年第1期13卷 285-296页

作者： Biswajit Bera Sumana Bhattacharjee Nairita Sengupta Soumik Saha Department of Geography Sidho-Kanho-Birsha UniversityRanchi RoadP.O.Purulia Sainik School723104India Department of Geography Jogesh Chandra Chaudhuri College(University of Calcutta)30Prince Anwar Shah RoadKolkata 700033India Department of Geography Diamond Harbour Women’s UniversitySarisha 743368India M.A. Independent ScholarDepartment of GeographyUniversity of Calcutta35Ballygunge Circular RoadKolkata 700019India

The higher concentration of PM_(10) and PM_(2.5) in the lower atmosphere is severely harmful for human health and it also makes visibility diminution along with weather and climate *** main objective is to find out the spatiotemporal variation and dispersal of PM_(10) and PM_(2.5) along with COVID-19 infection in the dusty city *** consecutive two years PM_(10) and PM_(2.5) data of different stations have been obtained from State Pollution Control Board,*** West *** trajectory analysis has been done through HYSPLIT(Hybrid Single Particle Lagrangian Integrated Trajectory)model to find the path and direction of air *** result showed that the various meteorological or environmental factors(such as temperature,relative humidity,wind,wind speed,pressure and gusty wind)and geographical location regulate the spatiotemporal variation of PM_(10) and PM_(2.5).These factors like high temperature with relative humidity and strong wind influence to disperse the particulate matters from north to south direction from city to outside during summer in Kolkata metropolitan *** summer(both pre and lockdown years),the height of particles is extended up to 1000 m owing to active atmospheric ventilation whereas in winter it is confined within 100 *** HYSPLIT model clearly specified that the particles dispersed from south,south-west to north and north east direction due to strong *** constant magnification of PM_(10) and PM_(2.5) in the lower atmosphere leads to greater frequency of COVID-19 infections and *** Kolkata,the one of the crucial reasons of high infection and deaths(COVID-19)is co-morbidity of people.

关键词： COVID-19 Lockdown variation Dispersal HYSPLIT model

variation and heritability of morphological and physiological traits among Leymus chinensis genotypes under different environmental conditions

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Journal of Arid Land 2019年第1期11卷 66-74页

作者： YANG Xue LI Junpeng ZHAO Tingting MO Lidong ZHANG Jianli REN Huiqin ZHAO Nianxi GAO Yubao Department of Plant Biology and Ecology College of Life Science Nankai University

Intraspecific trait variation and heritability in different environmental conditions not only suggest a potential for an evolutionary response but also have important ecological consequences at the population, community, and ecosystem levels. However, the contribution of quantitative trait variation within a grassland species to evolutionary responses or ecological consequences is seldom documented. Leymus chinensis is an important dominant species in semi-arid grasslands of China, which has seriously suffered from drought and high temperature stresses in recent decades. In the present study, we measured variation and heritability of 10 quantitative traits, namely the number of tillers, maximum shoot height, number of rhizomes, maximum rhizome length, rhizome mass, aboveground mass, root mass, maximum net photosynthetic rate(Pmax), specific leaf area(SLA), and leaf length to leaf width ratio(LL/LW), for 10 genotypes of L. chinensis under one non-stress(Ck) condition and three environmental stress conditions(i.e., drought(Dr), high temperature(Ht), and both drought and high temperature(DrHt)). Result indicated that(1) the interaction of genotype and environmental condition(G×E) was significant for 6 traits but not significant for the other 4 traits as shown by two-way analysis of variance(ANOVA), suggesting that different selection forces were placed for different traits on the factors dominating phenotypic responses to different environmental conditions. Moreover, these significant G×E effects on traits indicated significantly different phenotypic adaptive responses among L. chinensis genotypes to different environmental conditions. Additionally, individuals could be grouped according to environmental condition rather than genotype as shown by canonical discriminant analysis, indicating that environmental condition played a more important role in affecting phenotypic variation than genotype;(2) by one-way ANOVA, significant differences among L. chinensis genotypes w

关键词： Leymus chinensis genotype quantitative trait variation heritability drought high temperature

variation-Aware Task Mapping on Homogeneous Fault-Tolerant Multi-Core Network-on-Chips

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Journal of Beijing Institute of Technology 2019年第3期28卷 497-509页

作者： Chengbo Xue Yougen Xu Yue Hao Wei Gao School of Information and Electronics Beijing Institute of Technology

A variation-aware task mapping approach is proposed for a multi-core network-on-chips with redundant cores, which includes both the design-time mapping and run-time scheduling algorithms. Firstly, a design-time genetic task mapping algorithm is proposed during the design stage to generate multiple task mapping solutions which cover a maximum range of chips. Then, during the run, one optimal task mapping solution is selected. Additionally, logical cores are mapped to physically available cores. Both core asymmetry and topological changes are considered in the proposed approach. Experimental results show that the performance yield of the proposed approach is 96% on average, and the communication cost, power consumption and peak temperature are all optimized without loss of performance yield.

关键词： process variation task mapping fault-tolerant network-on-chips multi-core

variation OF WOVEN FABRIC GEOMETRY——Non-uniform Flattening of Yarns

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Journal of China Textile University(English Edition) 1993年第4期10卷 89-97页

作者：胡金莲 AlanNewton Textile Department UMISTManchesterU.K.

In previous research much effort has been devoted to the geometry of woven fabrics and relat-ed problems under the assumption of constant yarn configuration in *** paper will first re-port that image crimp (yarn crimp measured by an image analysis method) seems larger than *** the explanation of this result,the variation of yarn configuration in woven fabric dueto the non-uniform flattening is *** significance of this actual structure of woven fabricsis *** is believed that the variation of yarn configuration is very important for fabric per-formance,and may be an advantage for fabric quality.

关键词： variation yarn crimp image crimp woven fabric fabric quality fabric geometry non-uniform flattening

Computer comparisons in the presence of performance variation

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Frontiers of Computer Science 2020年第1期14卷 21-41页

作者： Samuel IRVING Bin LI Shaoming CHEN Lu PENG Weihua ZHANG Lide DUAN Louisiana State University Baton RougeLA 70803USA Shanghai Institute of Intelligent Electronics&Systems Shanghai 201203China Software School Fudan UniversityShanghai 201203China Shanghai Key Laboratory of Data Science Fudan UniversityShanghai 200433China University of Texas at San Antonio San AntonioTX 78249USA

Performance variability,stemming from nondeterministic hardware and software behaviors or deterministic behaviors such as measurement bias,is a well-known phenomenon of computer systems which increases the difficulty of comparing computer performance metrics and is slated to become even more of a concern as interest in Big Data analytic *** methods use various measures(such as geometric mean)to quantify the performance of different benchmarks to compare computers without considering this variability which may lead to wrong *** this paper,we propose three resampling methods for performance evaluation and comparison:a randomization test for a general performance comparison between two computers,bootstrapping confidence estimation,and an empirical distribution and five-number-summary for performance *** results show that for both PARSEC and highvariance BigDataBench benchmarks 1)the randomization test substantially improves our chance to identify the difference between performance comparisons when the difference is not large;2)bootstrapping confidence estimation provides an accurate confidence interval for the performance comparison measure(e.g.,ratio of geometric means);and 3)when the difference is very small,a single test is often not enough to reveal the nature of the computer performance due to the variability of computer *** further propose using empirical distribution to evaluate computer performance and a five-number-summary to summarize computer *** use published SPEC 2006 results to investigate the sources of performance variation by predicting performance and relative variation for 8,236 *** achieve a correlation of predicted performances of 0.992 and a correlation of predicted and measured relative variation of ***,we propose the utilization of a novel biplotting technique to visualize the effectiveness of benchmarks and cluster machines by *** illustrate the results and concl

关键词： performance of systems variation performance attributes measurement evaluation modeling simulation of multiple-processor systems experimental design Big Data

Soil contamination with antibiotics in a typical peri-urban area in eastern China: Seasonal variation, risk assessment, and microbial responses

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Journal of Environmental Sciences 2019年第5期31卷 200-212页

作者： Fangkai Zhao Lei Yang Liding Chen Qian Xiang Shoujuan Li Long Sun Xinwei Yu Li Fang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province Zhoushan Municipal Center For Disease Control and Prevention

The prevalence and persistence of antibiotics in soils has become an emerging environmental issue and an increasing threat to soil security and global public health. The problem is more severe in areas undergoing rapid urbanization; however, the ecological risks of antibiotics,seasonal variability, and associated soil microbial responses in peri-urban soils have not been well-explored. The seasonal soil sampling campaigns were conducted in a typical peri-urban watershed in eastern China to investigate distribution of antibiotics. The results demonstrated higher mean concentrations of most antibiotic compounds in winter than in summer in periurban soils. The seasonal variations of norfloxacin, enrofloxacin, and ciprofloxacin were more significant than those of other antibiotics, due to their higher migration ability and *** ecological risk assessment demonstrated that chlortetracycline, ciprofloxacin, doxycycline,and ofloxacin can pose high risks to soil microorganisms. Furthermore, the coexistence of multiple antibiotics obviously poses higher risks than individual compounds. A redundancy analysis demonstrated that tetracyclines mainly showed negative correlations with Firmicutes and Chloroflexi, and quinolones showed obviously negative correlations with Acidobacteria,Gemmatimonadetes, and Nitrospirae, suggesting potential inhibition from antibiotics on biological activities or biodegradation processes. However, the persistence of antibiotics in soil results in a significant decrease in bacterial diversity and a change in dominant *** results provide an overview of the seasonal variability of antibiotics and the associated effects on bacterial communities in peri-urban soils. The results can provide scientific guidance on decreasing soil contamination with antibiotics to enhance soil security in similar areas.

关键词： Antibiotics Soil Seasonal variation Ecological risks Bacterial community