1,720,968 research outputs found
(37(4):389-395)Influence of Paraquat and Defoliation on Maturity, Yield and Quality of Soybeans
No full text本試驗於大豆R6（full seed）時期以三種不同濃度（1D, 2D, 3D）落葉劑，和剪除上半部，下半部及全部葉片處理TNG 4, TNG 15, KS8與M34─1等四品系（種），探討落葉劑及剪葉處理對提早成熟期之效果與其對產量、品質之影響，並評估提早成熟期與產量之關係，以供栽培及育種參考，結果摘要條列如下：
一、落葉劑paraquat及剪葉處理均可獲致提早成熟期與降低倒伏率之效果，但同時會造成產量嚴重損失及種子品質低落等不良影響。
二、使用之三落葉劑濃度間對產量降低之影響無顯著差異，然而隨濃度增加，可獲較佳提早成熟期與降低倒伏率效果。
三、除TNG 15外，其他三品種（系）剪除具有遮蔭效果之上半部葉片或下半部葉片，均未顯著提早成熟期，但均會降低產量，顯見大豆生育後期遮蔭作用並非決定成熟期之關鍵，但剪除全部葉片則可顯著提早成熟期。
四、落葉劑及剪葉處理造成產量嚴重損失，係因莢數與百粒重同時降低所致。
五、以落葉劑及剪葉處理提早成熟期七天，將造成約30％以上產量損失，故除非為防止天然災害，否則不值得採用。
To evaluate the relation between accerating harvest and yield reduction of soybeans, 3 concentrations of paraquat and 3 defoliation treatments (including cutting of upper 50%, lower 50% and whole leaves) were applied at R6 (full seed) growth stage. The results were summarized as following:
1. Paraquat and defoliation treatments could accerate harvest, but reduce yield and seed quality also.
2. There was no significant difference in yield reduction among 3 concentrations of paraquat treatments, however high concentration had better effects on accerating harvest and decreasing lodging.
3. Cutting of upper 50%, the main part causing the shading effects, and lower 50% leaves had no significant effect on accerating harvest, but on yield reduction, showing that shading was not the decisive factor for maturity at late growth stage of soybeans.
4. The result of enormous yield reduction by paraquat and defoliation treatments is caused from the decrease in pod number and 100 seed weight.
5. Evaluating between shorting 7 days to maturity and inducing more than 30% yield reduction, indicated that the treatments of paraquat and defoliation were not worth recommending
Intelligent Virtual Impedance Based Control to Enhance the Stability of Islanded Microgrid
No full textThis paper focuses on the voltage stability issue of an islanded microgrid in a cost-effective way adding the concept of adaptive virtual impedance. In the islanded microgrid structure, the mis-match of line impedance between the Distributed Generation (DG) units and imbalance of inverter local load are two critical factors to be dealt with carefully. These can result in serious circulating current and unreasonably reactive power sharing among DG units by using the conventional droop control method. In practical engineering, line inductance is often increased to eliminate the impedance mismatch. However, such a method would lead to an increase in cost, weight, and volume. To solve this problem, an adaptive virtual impedance droop control strategy based on fuzzy controller is proposed. Instead of DG units are equipped with series inductors, an adaptive virtual impedance is introduced to adaptively eliminate the reactive power error caused by the inconsistency of the line impedance through the fuzzy controller. At the same time, in order to deal with the droop control and the voltage drop at the inverter output caused by the addition of virtual impedance, a voltage compensation link is introduced to maintain the voltage within an acceptable range. The simulations were performed in Matlab/Simulink and RT-LAB experiments to verify the validity of the proposed control strategy.National Natural Science Foundation of China, 61873159, Shun fu Lin, Science and Technology Commission of Putuo District, 18020500700, Shun fu Lin, Shanghai Key Laboratory of Embryo and Reproduction Engineering, 13DZ2251900, Shun fu Lin
(50(3):12-24)Identification of the Inconsistence between Genomic Constitution and Phenotypic Variation in Interspecific Hybrids (4x×2x) of Peanut with DNA Marker
No full text本研究利用RAPD及SSR分子標識來分析落花生不同倍數性種間雜種（4x×2x）的多型性產生之頻率，並探討不同倍數性之種間親本對後代DNA多型性之貢獻是否有差異存在。試驗結果顯示，使用水稻或玉米的Intra-SSR引子可由PCR增幅落花生基因組約11個DNA片段，而Inter-SSR則可由PCR增幅約7個落花生DNA片段。Intra-SSR及Inter-SSR單一引子產生親本多型性之比率，平均分別為45.4％及45.1％高於RAPD的41.6 %。而Intra-SSR及Inter-SSR產生各個條帶之多型性比率分別為34.2％及36.0%，亦高於RAPD的33.6％。而不論是RAPD或SSR的分析，可發現F1的DNA條帶形式與栽培種母本相近，且其多型性條帶平均有66.8％是來自母本，只有33.2％的條帶是來自野生種父本，此種結果與基因組來源及貢獻量相符，但是卻與種間雜交種之外表型變異傾向於野生種之結果不合。因此，本試驗由分子層次確認支持基因組大小與植株外表型變異之不一致性。建議本試驗結果，可提供作物基因組及基因表現研究與種間雜交利用於品種改良之參考。In this study RAPD and SSR markers were used to analyze genomic context of interspecific hybrids (A. hypogaea L. × A. spegazzinii L.) of peanut. Frequencies and parental origins of DNA polymorphic bands were investigated for the interspecific hybrids (4x×2x). The results indicated that about 11 bands were PCR amplified from total genomic DNA of peanuts with intra-SSR primers of rice or corn, and about 7 bands were amplified with inter-SSR primers. The averaged polymorphic rates were 45.4% and 45.1% for a pair of intra-SSR primer and an inter-SSR primer, respectively. However, the averaged polymorphic rate for a RAPD primer was 41.3%. The percentages of a (pair of) primer with polymorphic bands between interspecific parents were 34.2, 36.0% and 33.6% for intra-SSR (rice/corn), inter-SSR, and RAPD primers, separately. About twice (66.8%) polymorphic bands were contributed from allotetraploid parent compared to diploid parent (33.2%) providing molecular evidence of genomic context of interspecific hybrids and inconsistence between genomic contribution and phenotypic variation. This information is valuable for genome and gene expression studies as well as the utilization of interspecific hybridization in plant breeding
Polymorphic differentiation and genetic variation of soybean by RFLP analysis
No full textTwenty soybean accessions, representing local varieties, improved cultivars, plant introductions, breeding lines, two pairs of isogenic lines with different seed coat colors, and one Glycine soja accession were used for detecting genetic differentiation by restriction fragment length polymorphism (RFLP) markers. Seventeen probes which are believed to be primarily single copy sequences derived from a soybean genomic library of PstI digests were used. Eleven of these seventeen probes were proved to yield polymorphisms in one- or two-enzyme digestion. From a total of fifty-three probe -enzyme combinations, fifteen demonstrated polymorphism among accessions. DNA digested with HindIII showed a higher percentage of polymorphisms. The number of polymorphic alleles estimated from this study was forty-three alleles over twenty-five loci. Among these, 20% of loci have G. soja specific differences. Both dominant and codominant loci were noted, with 36% and 64% respectively. Alleles occurring in one or two accessions are considered rare. Fifty-six percent of polymorphic loci predominantly had rare allele, and only 44% of loci were informative. Variations within accessions were also noted with some probe-enzyme combinations. An average of 0.236 heterozygosity per locus was obtained from these RFLP marker loci. Dendrograms based on the coefficient of genetic similarity derived from this RFLP data classified the twenty accessions into five groups. Genetic differentiation could be achieved in eighteen of twenty soybean accessions by eleven probe-enzyme combinations. However, difficulty in distinguishing one pair of isogenic lines remained
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
