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Mechanism of Polymorph Selection during Crystallization of Random Butene-1/Ethylene Copolymer

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Chinese Journal of Polymer Science 2016年第8期34卷 1014-1020页

作者： Yao-tao Wang Pei-ru Liu Ying Lu 门永锋 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Starting from an initial sample of butene-1/ethylene copolymer with stable form I＇, we examined the nucleation of different crystalline polymorphs （here metastable form II and stable form I＇） at different isothermal crystallization temperatures after being melted at different melt temperature （Tmelt）. When Tmelt was just above the melting temperature （Tm） of the crystallites, self-seeding took place. There, residue crystallites served as nuclei leading to the crystallization of the same crystalline phase. When Tmelt was a few degrees above the Tin, self-seeding was disabled due to complete melting of the initial crystals. Upon crystallization, the selection of the different polymorphs in this random copolymer was found to depend on an interplay between the domain size of segregated long crystallizable sequences and the size and energy barrier of the critical nucleus of the respective crystalline forms. Our results provide a clear understanding of the polymorphs selection during crystallization of a random copolymer as well as homo-polymers under confinement.

关键词： Crystallization Random copolymer Polybutene-1 polymorphism.

“Pachyostosis” in aquatic amniotes: a review

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Integrative Zoology 2009年第4期4卷 325-340页

作者： Alexandra HOUSSAYE Department of Earth History Museum of Natural HistoryParisFrance

During the course of amniote evolution,numerous taxa secondarily adapted to an aquatic *** appears that many of these taxa primitively display“pachyostosis,”an osseous specialization characterized by an increase in bone compactness and/or *** term“pachyostosis”is used in morphological and histological descriptions to describe what in fact corresponds to different *** aim of this paper is to present the current state of knowledge relative to this adaptation among aquatic *** the taxa that have returned to an aquatic environ-ment are ***,their degree of adaptation to the marine environment,their life environment,and the nature of their“pachyostotic”pattern,when present,are *** inventory enables the evaluation of the current quality of the data relative to this specialization and provides an indication of the work that remains to be *** functional consequences of“pachyostosis,”and notably its importance for buoyancy control in the context of hydrostatic regulation of the body trim,are discussed and opposed to the requirement of improved swimming abilities in the case of a hydrodynamic mode of trim *** are posed about the significa-tion of the polymorphism.displayed by this specialization between different taxa,different specimens of the same taxon and different bones of the same specimen,and the problem of quantification of pachyostosis is discussed.

关键词： buoyancy control life environment locomotion “pachyostosis”sensu lato polymorphism.

Single nucleotide polymorphism.analysis on melanocortin receptor 1 (MC1R) of Chinese native pig

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Science China(Life Sciences) 2004年第3期47卷 287-292页

作者： SHI Kerong1,2, WANG Aiguo1, LI Ning2 & DENG Xuemei1 1. College of Animal Science and Technology, China Agricultural University, Beijing 100094, China 2. National Laboratory for Agribiotechnology of China Agricultural University, Beijing 100094, China College of Animal Science and Technology China Agricultural University Beijing China National Laboratory for Agribiotechnology of China Agricultural University Beijing China

Melanocortin receptor 1 (MC1R) gene, one of the important candidate genes for coat color trait, was used to analyze the single nucleotide polymorphism.(SNP) in Chinese native pig breeds by PCR-single strand conformation polymorphism.(PCR-SSCP). The study had also taken 3 imported pig breeds as control. The results showed that the three mutations G284A, T309C and T364C found in Chinese native pigs were consistent to the mutation found in the European Large Black individuals. However, 68CC or C492T and G728A were only found in the imported individuals, which were obviously different from the Chinese native pigs. Accordingly, we presumed that the coat colors of Chinese native pigs belonged to dominant black color sys-tem, which was completely distinct to that of imported pig breeds. Thus it was implied that MC1R gene was not the principal factor affecting the coat color differences of Chinese native pig breeds, but could be used to trace the molecular evolution of pig breeds.

关键词： pig, coat color, MC1R gene, polymorphism.

The origin of Mosuo people as revealed by mtDNA and Y chromosome variation

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Science China(Life Sciences) 2004年第1期47卷 1-10页

作者： WEN Bo, SHI Hong, REN Ling, XI Huifeng, LI Kaiyuan, ZHANG Wenyi, SU Bing, SI Shiheng, JIN Li & XIAO ChunjieJoined Laboratory of Human Population Genetics of Yunnan University and Fudan University, Kunming 650091, China Key Laboratory of Bioresources Conservation and Utilization & Human Genetics Center of Yunnan University, Kunming 650091, China National Key Laboratory of Genetic Engineering & Center for Anthropological Studies, School of Life Sciences, Fudan University, Shanghai 200433, China Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650031, China Center for Genome Information, Department of Environmental Health, University of Cincinnati, Cincinnati 45267, USA The Central Hospital of Ninglang County, Ninglang 674300, China Joined Laboratory of Human Population Genetics of Yunnan University and Fudan University Kunming China Key Laboratory of Bioresources Conservation and Utilization & Human Genetics Center of Yunnan University Kunming China National Key Laboratory of Genetic Engineering & Center for Anthropological Studies School of Life Sciences Fudan University Shanghai China Kunming Institute of Zoology Chinese Academy of Sciences Kunming China Center for Genome Information Department of Environmental Health University of Cincinnati Cincinnati USA The Central Hospital of Ninglang County Ninglang China

The Mosuo, living in the Lugu Lake area in northwest Yunnan Province, China, is the only matriarchal population in China. The Mosuo was officially identified as Naxi nationality although its relationship with Naxi remains controversial. We studied the genetic relationship between the Mosuo and five other ethnic groups currently residing in northwest Yunnan, i.e. Naxi, Tibetan, Bai, Yi and Pumi, by typing the genetic variations in mtDNA HVS1 and 21 Y chromosome markers (13 SNPs & 8 STR markers). We showed that the maternal lineages of the Mosuo bear the strongest resemblance with those found in Naxi while its paternal lineages are more similar to those that are prevalent in Yunnan Tibetan. The marked difference between paternal and maternal lineages may be attributable to the genetic history, matriarchal structure, and visiting marriage.

关键词： Mosuo, mtDNA, Y chromosome, polymorphism.

Distribution of YAP in 10 populations of China

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Chinese Science Bulletin 1998年第12期43卷 1023-1025页

作者： Xu Liping Xu Jiujin Zhu Suling Bao Weidong Du Ruofu Chinese Acad Sci Inst Genet Beijing 100101 Peoples R China

The Y_chromosome Alu polymorphism.was studied in 10 populations in China. The Alu insertion is present in 54/571 individuals (9%). Among 10 populations, the frequency of YAP element is quite high (49%) in the Tibetans and at moderate or low levels (15%-4%) in the Yi, Hui and Uygur. The Alu insertion is absent in the Han in Guangdong and Shaanxi, and in the Manchu and Zhuang, while a single Tujia individual and a single Yao individual are found to have the Alu insertion.

关键词： Chinese populations Y chromosome Alu genetic polymorphism.

CHARACTERIZATION, DEVELOPMENT AND EXPLOITATION OF ESTDERIVED MICROSATELLITES IN GOSSYPIUM RAIMONDII ULBRICH

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Science Bulletin 2006年第5期51卷 557-561页

作者： WANG Changbiao, GUO Wangzhen, CAI Caiping & ZHANG Tianzhen National Key Laboratory of Crop Genetics & Germplasm Enhancement, Cotton Research Institute, Nanjing Agricultural University, Nanjing 210095, China National Key Laboratory of Crop Genetics & Germplasm Enhancement Cotton Research Institute Nanjing Agricultural University Nanjing China

Microsatellite DNA or simple sequence repeats (SSRs) can be derived from expressed se- quence tags (ESTs). These markers are important for gene mapping as well as marker-assisted selection (MAS). To develop EST-SSRs for cotton gene map- ping, we selected and characterized functional markers in Gossypium raimondii, which consisted of 58906 non-redundant EST sequences from NCBI. Among them there were 2620 microsatellite se- quences containing 2818 EST-SSRs, which amoun- ted to 4.45% of the non-redundant starting sequence population. This incidence was equivalent to one EST-SSR in every 14.8 kb of G. raimondii genetic material. Among the different motifs ranging from 1 to 6 bp, trinucleotide repeats were most abundant (38.31%), followed by dinucleotide repeats (24.09%) and mononucleotide repeats (23.35%). Among all identified motif types, A/T had the highest frequency (18.67%), followed by AT/TA (14.83%). Among the compound motifs, tandem trinucleotides occurred with the highest frequency (48.65%). In all, we identi- fied 1554 EST-SSRs primer pair sequences. 300 of them were randomly selected to screen the poly- morphisms between the mapping parents G· hirsutum acc. TM-1 and G· barbadense cv. Hai7124, to con- struct linkage groups in cultivated allotetraploid cot- ton. Among them, 129 (43%) primer pairs were found to have polymorphism.. Using these EST-SSRs we can compare EST-SSR distributions among different cotton species and various chromosomal locations.

关键词： Gossypium raimondii Ulbrich EST-SSRs distribution molecular marker polymorphism.

BamHI　AND　RsaI　RESTRICTION　FRAGMENT　LENGTH　polymorphism.　IN　RETINOBLASTOMA　GENE　IN　A　CHINESE　POPULATION

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Chinese Journal of Cancer Research 1995年第4期7卷 255-257页

作者：魏军杜传书 Department of Medical Genetics Sun Yat-sen University of Medical Sciences Guangzhou

The retinoblastoma (Rb) gene probe p123 M 1.8 andP68 Rs2.0 were used to study the frequencies of *** and Rsal restriction fragment length polymorphism. (RFLPs) in the Rb gene among the population of Han nationality in Guangdong *** result showed that the heterozygotic rate of the Rsal locus was only 55.0%. Linkage study of the BamHI and the Rsal RFLPs demonstrated that 10.s% of the Rsal polymorphic loci were heterozygous for the BamHI *** the combined use of the two RFLPs can give information for about 65.5% of the population.

关键词： Retinoblastoma(Rb) gene BamHI RsaI polymorphism.

Effect of Long-Term in Vitro Sub-culturing on Quality Degeneration of Sweet Potato Varieties： Morpho- Anatomic Assessment and Simple Sequence Repeats Analysis

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Journal of Agricultural Science and Technology(A) 2014年第10期4卷 811-821页

作者： Mihiretu Cherinet Hundayehu Elsa Du Toit Sunette Laurie Martin Steyn Ria Greyling Nokuthula Myeza Department of Plant Production and Soil Science University of Pretoria Lynwood Road Pretoria 0002 South Africa Agricultural Research Council-Roodeplaat Vegetable and Ornamental Plant Institute (ARC-VOPI) Private Bag X293 Pretoria0001 South Africa

The aim of this study was to assess the effect of long-term in vitro sub-culturing on the varietal degeneration of three sweet potato varieties, namely, Monate, Mokone and Ndou which were sub-cultured for 32, 23 and 12 generations, respectively. Each generation was cultured in a media which is made from 4.43 g/L Murashige and Skoog （MS）, 30 g/L sucrose and 2 g/L gelrite, respectively, and grown under 16 h light and 8 h dark photoperiod for 30 d. For each generation, 45 plantlets were acclimatized for two months in a glasshouse. Data on in vitro growth performance and 11 morphological characteristics during acclimatization were recorded. Early root and shoot formation was observed after the 27th and 21st sub-cultured generations of Monate and Mokone, respectively. During acclimatization, plantlets from the same variety showed differences in morphological traits such as leaf colour, abaxial leaf pigmentation, vine pigmentation, petiole pigmentation, leaf wrinkling and flowering. However, the rate of these morphological differences is random and irrespective to increase in sub-culturing. Therefore, to understand the genetic base of these morphological variability, two plantlets from each variety were subjected to genetic analysis by using five simple sequence repeat （SSR） primers （IB-242, IB-318, IB-255F, 1B-248 and IB-255）. Although SSR loci IB-255F and IB-318 could distinguish between the three varieties, there were no allelic polymorphism. detected in plantlets from the same varieties. Therefore, long-term sub-culturing do not leads to quality degeneration in the three sweet potato varieties.

关键词： Micro-propagation organogenesis sub-culture true-to-type morphology polymorphism.

Cloning, sequencing and polymorphism.analyzing of the exon 4 of the kappa-casein gene in yak

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Progress in Natural Science:Materials International 2000年第10期 51-55页

作者：樊宝良李宁胡晓湘吴常信 Beijing 100094 China China Agricultural University College of Animal Science and Technology Handan 057150 Hebei Handan Agricultural college State Key Laboratories for Agrobiotechnology

According to the nucleotide sequence of cattle kappa-casein gene, a pair of primers was synthesized to amplify the sequences of the exon 4 and partial intron 4 of this gene in yak. The restriction fragment length polymorphism. were identified by the digestions of the PCR product with Hind Ⅲ or Pst I in both populations of cattle and yak, but the frequency of the allele and the genotype were significantly different between the two animal populations.

关键词： yak kappa-casein gene exon 4 polymorphism.