Genetic Improvement of Leucaena and Acacia Koa

Studies on Leucaena and Acacia koa tree improvement were undertaken in Hawaii from 1992-1996. These studies were described in two sections. The first section includes identification of high biomass yield varieties, estimation of DNA content, vegetative propagation, and forage yield management among Leucaena species and hybrids. Among interspecific hybrids of KX2 F1 (L. pallida x L. leucocephala) and 3-way crosses (A. pallida x KX3 F1 (L. diversifolia x L. leucocephala)), the best entries yielded over 16 Mg ha-1yr-1 of edible forage dry matter and over 40 Mg ha-1yr-1 for wood biomass. All these hybrids were psyllid-tolerant. Heterosis for forage yield averaged 48% (-75 to 160%) and for wood biomass averaged 85% (-99 to 223%). Among intraspecific hybrids involving six L. leucocephala accessions, the best entries were the crosses between K397, K565, and K608. They outyielded a widely planted K636 (L. leucocephala). Heterosis for biomass yield averaged 16% (-28% to 80%). A composite from the selected intraspecific hybrids was released. Nuclear DNA content varied from 1.32 to 1.74 pg/2C for diploid species and from 2.67 to 3.09 pg/2C for tetraploid species. Successful cloning method with more than 80% rooting for KIOOO and KlOOl was developed. More than 30% increase in forage yield was obtained by optimizing the harvest intervals of K636 and KX2 F1. The second section includes studies of the identification of quality seed source for reforestation and selection of superior progenies for genetic improvement among Acacia koa collections. A total of 334 koa accessions were collected from the Hawaiian Islands. These accessions were evaluated for various important traits from seed to tree growth characters. Seven field trials involving 178 accessions were established at Hamakua, Hawaii and Mauanawili, Oahu. The koa populations clearly showed great variations in these traits. These variations are essentially genetic in origin and are useful in selecting progenies for tree improvement. High quality koa seed sources from the Islands were identified. The advanced progenies based on fast growth and tree form were selected for further testing. Silviculture practice study showed that koa trees in the mixed plots grew significantly slower than trees grown alone

Isozyme Polymorphism in the Leguminous Genus Leucaena

The leguminous genus Leucaena includes 15 species, several of which have become pantropical owing to their importance as fodder, fuelwood, shade and ornamental trees. In all present study, protocols for obtaining reproducible isozyme phenotypes in Leucaena were developed for six isozyme systems (AGO, ADH, IDH, MDH, PGI and PGI) using Lhistidine and citric acid for running and tray buffers with cotyledon tissues. Standard descriptions of isozymic phenotypes were established using accession K997 of a local Hawaiian population L. leucocephala ssp. leucocephala as a control. Ontogenetic studies revealed that ADH phenotypes were developmentally variable. However, the phenotypes of other isozyme systems were not variable ontogenetically. One hundred sixty-nine accessions of 12 Leucaena species, including 3 tetraploid species and 9 diploid species, were analyzed for six isozyme systems. Extensive polymorphism was observed among the species, and the weighted polymorphism (Pw) was estimated. The higher Pw values characterized outcrossing species and the lower PwS were among self-pollinated species. Five of these isozyme systems (AGO, ADH, IDH, MDH and PGI) provided bands that were found useful in identifying taxa within the genus. These systems were also effective in detecting inter- and intra-specific hybrids. Three loci of AGO and two loci of IDH in the sibcrosses of L. lanceolata (K10) were confirmed. Seventy-nine accessions of "common" L. leucocephala ssp. leucocephala from tropical countries and thirty-six of "giant" L. leucocephala ssp. glabrata, mainly from Central America were tested for isozyme variation. The uniformity of isozymic expression of all "common" types suggests that they are offsprings of a "pure" line variety or a single tree. In contrast, the "giant" types of L. leucocephala ssp. glabrata were quite diverse. The "giant" type trees could be easily distinguished from the "common" in the AGO system. The ancestral relationship of Leucaena diploids and polyploids were analyzed using the electrophoresis technique. The results did not support the hypotheses that (1) L. diversifolia ssp. diversifolia (2n=104) is an autotetraploid from L. diversifolia ssp. trichandra (2n=52) and (2) L. pallida (2n=104) is an amphidiploid from L. diversifolia ssp. trichandra and L. esculenta (2n=52)

Study on Long-term Mechanism for Government to Encourage Enterprises on Low-carbon Development——Analysis based on Enterprises’ Capacity Variance and Task Difficulty

AbstractBased on reference to Lazear and Rosen (1981) rank-order tournaments mechanism model, this essay introduces the two variables, namely capacity variance and task difficulty, to establish a long-term mechanism model for the government to encourage enterprises for low-carbon development. It is included through model analysis that, the optimal effort level during enterprises’ low-carbon development is directly proportional to bonus difference (L-l) set by the government, and inversely proportional to task difficulty, capacity variance and “performance” appraisal error. When enterprises’ capacities are identical, their optimal effort level will be the highest and equal. Besides, the government should take task difficulty and capacity into comprehensive consideration to set reasonable bonus difference. If task difficulty is relatively large, the government should enlarge bonus difference; if task difficulty is small, the government should correspondingly shorten bonus difference

百年来の中国における万暦朝鮮の役（文禄・慶長の役） 研究の回顧

Over the past hundred years, the Chinese research approach to the Wanli Korean War has changed from “no emphasis placed on the Wanli Korean War” to “high emphasis placed on it,” from research subject to serious political interference to rigorous academic research, and from research focused specifically on the Ming’s participation in the war to research aimed at reaching a comprehensive understanding of the war from various East Asian perspectives. Research results were published mainly in monographs rather than in systematic academic books. Moreover, the research results mainly presented the description of historical facts and a list of historical materials because of a longstanding lack of academic interest. However, since the early 2000s, the number of researchers in this field has increased. They have made extensive use of historical materials from China, Japan, and Choson Korea and have comprehensively advanced the investigation of this topic from the perspectives of East Asia and new cultural history, gradually integrating it into the mainstream of international academic research

Methods to Improve the Teaching Effect of the Professional Course of the University

Aiming at the poor teaching effect of professional course in university, student interest is not high and show how to improve the important measures of the teaching effect of professional course in university and universities, starting from the view of teachers, effective preparation is the prerequisite to improve the professional teaching, effective classroom teaching is the effective guarantee to improve the teaching of professional course, advanced teaching methods is the fundamental guarantee to enhance the teaching of professional courses, starting from the perspective of students, learning interest is the basic power, improve the teaching of professional courses ability is the fundamental aim of improve the teaching of professional courses

A Correlation Information-based Spatiotemporal Network for Traffic Flow Forecasting

The technology of traffic flow forecasting plays an important role in intelligent transportation systems. Based on graph neural networks and attention mechanisms, most previous works utilize the transformer architecture to discover spatiotemporal dependencies and dynamic relationships. However, they have not considered correlation information among spatiotemporal sequences thoroughly. In this paper, based on the maximal information coefficient, we present two elaborate spatiotemporal representations, spatial correlation information (SCorr) and temporal correlation information (TCorr). Using SCorr, we propose a correlation information-based spatiotemporal network (CorrSTN) that includes a dynamic graph neural network component for integrating correlation information into spatial structure effectively and a multi-head attention component for modeling dynamic temporal dependencies accurately. Utilizing TCorr, we explore the correlation pattern among different periodic data to identify the most relevant data, and then design an efficient data selection scheme to further enhance model performance. The experimental results on the highway traffic flow (PEMS07 and PEMS08) and metro crowd flow (HZME inflow and outflow) datasets demonstrate that CorrSTN outperforms the state-of-the-art methods in terms of predictive performance. In particular, on the HZME (outflow) dataset, our model makes significant improvements compared with the ASTGNN model by 12.7%, 14.4% and 27.4% in the metrics of MAE, RMSE and MAPE, respectively.Comment: 19 pages, 13 figures, 5 table