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The Lanyu pig is an indigenous miniature pig breed on Lanyu Islet near Taiwan, with a mitochondrial DNA genetic lineage remote from Asian and European pig breeds. The unknown population genetic structure and increased inbreeding among the small population of conserved Lanyu pigs is now of great conservation concern. Additionally, the presence for more than a century of exotic pig breeds in Taiwan has made gene introgression from exotic pig breeds into Lanyu pigs very possible. The present study thus aimed to investigate nuclear genetic variation within the conserved Lanyu pigs and the phylogenetic relationship and possible genetic introgression between Lanyu and exotic pig breeds by determining the polymorphism of 19 microsatellite loci. In the neighbor-joining tree constructed from 7 pig breeds based on Cavalli-Sforza and Edward chord genetic distances, 3 major clades were recognized, in which the Asian and European breeds were separately clustered into 2 clades with a 93.0 and 99.9% bootstrap confidence value, respectively. All individuals of the Lanyu breed formed a unique subclade within the Asian clade based on the distance of the proportion of shared alleles, -1n(ps), suggesting that the Lanyu breed possesses a unique nuclear genetic structure and that no nuclear gene introgression from exotic breeds into the conserved Lanyu pigs has occurred in recent history. Fifteen of 19 microsatellite loci deviated from Hardy-Weinberg equilibrium (by Wright's statistic), suggesting a significant loss of heterozygosity in the conserved population. The valuable nuclear genetic structure and phylogenetic information should assist future conservation and population management of Lanyu pigs. Key words: genetic variation, introgression, Lanyu breed, microsatellite, phylogenetics, pig

Research was conducted to examine the arylvinylation of 1,6-dibromo- and 2,6-dibromooaphthyl derivatives by the Heck reaction. Results demonstrate that depending upon the phosphines and solvents used, the dibromoarenes could undergo either mono- or bis-arylvinylation. The arylvinylated products display intense fluorescence and mesophase behaviors, specifically the B-type molecules. NMR spectroscopy was used to study the photoisomerization.

Rayleigh acoustic mode in superlattice films with layers of a-Si:H and a-SiN(x):H is studied by the application of Brillouin light-scattering technique. Superlattices with different thicknesses of Si:H layers are analyzed, and the phase velocity of the Rayleigh mode is determined. Anomalous properties determined from ultrasonic measurements in superlattices are not observed by using Brillouin light-scattering method.

A time-of-flight secondary ion mass spectrometry is utilized to examine the diffusion mechanisms of fluorine ions in GaN. Strong local confinement and stabilization of fluorine ions in GaN crystal achieved by significant reduction in the number of continuous vacancy chains revealed excellent thermal stability of fluorine ions for device applications.

The molecular dynamic simulation method is used for calculating the potential energies of interstitial and substitutional fluorine ions in AlGaN/GaN material system. It is shown that the fluorine ions are located at the substitutional group-III cation sites S(III) and the diffusion of fluorine ions in implanted III-nitride semiconductors is dominated by S(III)-interstitial process.