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Shengguo Fang and Qianghua Xu

Abstract

Variable number tandem repeats (VNTRs) are present in the control region of mitochondrial DNA (mtDNA) of the alligatorid species; however, the evolutionary dynamics of the repetitive sequences and the significance of the VNTRs in the context of genetic monitoring of these species are not well explored. The Chinese alligator, Alligator sinensis is critically endangered and is now largely in captive breeding. Previous studies in mitochondrial genes revealed little genetic diversity existing within the populations. We reported here the structural variation and evolutionary features of mtVNTRs in the Changxing population of the species. The mtVNTRs contained 676∼785 base pairs, made up by 5 distinct motifs repeated 31∼36 times in 32 individuals examined. The motifs were 21∼22 nts in length, with high sequence similarity between each other and with those of the American alligator (Alligator mississippiensis), indicating origination of the mtVNTRs from a single ancestral duplication unit in both species. The 5′ and 3′ portions of the repetitive sequences in the Chinese alligator were very much conserved among the individuals, while those in the middle showed a higher degree of sequence variation. The frequency of each motif appearing in the mtVNTRs showed positive correlation to the binding energy of the potential secondary structure the motif could adopt. 17 VNTR types, of which, 6 from the second generation and 12 from the third generation were identified from the samples. Analysis of the multiple VNTR types showed a high level of stochastic mutation within each generation. The suitability of the mtVNTRs as a marker to monitor the genetic differentiation of the Chinese alligator was also discussed.

Fang Xu, Yixiang He and Imad Khan

This chapter explores a visual reinterpretation that represents the complex physical environmental transformation of the Rocks in Sydney. As a famous historical site, the development of the Rocks is the result of the interactions of the social, economic and cultural changes in the past 100 years. It can be seen as the most representative example of urban-scape development of a historic city in Australia. Many previous studies of the Rocks mainly focused on heritage protection, historical events, the historical photography and documents collection. However the physical environment of the Rocks as a whole that witnesses the past changes has not been systematically studied. The general public cannot find the concise materials that can help them to understand the site. They are very critical to the current and future exercise of urban renewal projects of the site. The difficulty is how one can find an innovative way to effectively represent the research outcomes. This chapter highlights the visual reinterpretation as the key issue. Inspired by the art works of Escher, M.C. Escher has developed a special visual reinterpretation method in his graphic works. Based on a series of meaningful exercises, the chapter identifies the unique characteristics of the physical environment of the Rocks. Through revealing the layers of the Rocks, it classifies the main features of many restoration projects of the site into three essential categories. The developed visualization method provides an effective tool to deconstruct the multifaceted buildings forms, offering a new perspective to induct the general patterns of the complicated configurations and transformation of the urban historical site. The chapter’s outcome can be used as a valuable reference to direct future design intervention in an urban historical site.

GONG Fang, XU Juan, FU Jian, DENG Sanhong and BAI Yun

Based on the analyses on the quality of educational periodicals and the number of publications and citations in Chinese Social Sciences Citation Index (CSSCI), this paper intends to make an analysis and introduction of the general situation of Chinese educational journals and publications during 2000–2004. Results show that the quantity of educational periodicals and papers published in China, their influence, “impact factor” and the quantity of language varieties and quotation types are not completely compatible.

Xu Wang, Yiwu Fang, Munawar Maria, Jianfeng Gu and Jianjun Ge

Summary

Bursaphelenchus rockyi n. sp., isolated in Peking, China, from peat moss imported from Russia, is described. It is characterised by a lateral field with four lines, excretory pore located at the base of the nerve ring or slightly posterior, spicule 15.9 (15.1-17.3) μm long along the chord and with high condylus and a rounded tip, rostrum triangular or conical with bluntly pointed tip, lamina curvature becoming more pronounced at 60% of total length, six caudal papillae with P3 and P4 adjacent to each other, bursa small, starting posterior to P4, vulval lips hemispherical and protruding, and tail conical with finely rounded or mucronated terminus. The new species belongs to the fungivorus-group and is most similar to B. arthuri, B. arthuroides, B. fungivorus and B. seani, but can be distinguished from related species by morphological and sequencing results.

KUNSONG CHEN, CHANGJIE XU, FANG LI and SHANGLONG ZHANG

Knowledge of the mechanisms involved in postharvest granulation of 'Huyou' (Citrus changshanensis K.S. Chen et C.X. Fu) citrus fruit is quite limited. Thus, this study was conducted to explore the physiological changes that occur during granulation and the effects of calcium ion on them. Incipient granulation of juice sacs began in mid-March of the year following, as shown by the increase in granulation index, and it was found that 4% CaCl2 had a stronger effect on retardation of fruit granulation than 100 mg/L GA3 treatment. Different changes in activities of superoxide dismutase (SOD) in juice sacs and peel tissue during juice sac granulation and following CaCl2 treatment were observed, and it is suggested that juice sacs undergo a senescence process during granulation, while peel tissue does not. Evidence for transport of 14C-glucose from juice sacs to peel tissue prior to the commencement of granulation was recorded. The mechanisms for fruit granulation are discussed, with an emphasis on senescence of juice sacs and regrowth of peel tissue.

Xu-Guang Liu, Zhi-Zhong Zhang, Yun-Hai Zhang, Yun-Sheng Li, Fu-Gui Fang, Feng-Yin Li and Yong Tao

Abstract

The present study was carried out to describe the reproductive system of a single adult female wolf, including the uterine horns, cervix, ovaries and follicles. The cumulus oocytes complexes (COCs) and oocytes were also examined. The results showed that the size of each ovary was about 9 × 6 mm with an average of weight of 461.3 mg. The uterus was Y-shaped, and the length of each uterine horn was 14 cm. The distance from the cervix to the bifurcation of the uterine horns was also 14 cm. The left ovary had two large follicles on the surface with a diameter more than 4 mm, while the right ovary had no protuberant follicles. The ovaries were covered with a lot of fat, and were well developed. The COCs derived from the antral follicles were dark, and the nuded oocytes had a dark cytoplasm. The diameter of the oocytes removed from the antral follicles was 116.8 μm on average. The ovaries had a smooth surface and all the follicles were under the surface except for two big follicles on the left ovary. Histological examination of the ovaries by haematoxylin and eosin staining demonstrated that the primordial, primary, preantral and antral follicles were scattered in the cortex, the medulla was abundant with blood vessels. This study preliminarily reveals the features of the wolf reproductive system and the structure of its oocytes and ovaries, which might be indicative for further study and the protection of the species.