Judul: Variasi Kloroplas Shorea laevis Ridl. Di Kalimantan Berdasarkan Penanda Mikrosatelit
Abstrak: Shorea laevis Ridl. merupakan salah satu jenis penting dari famili Dipterocarpaceae ditinjau dari segi ekologi maupun ekonomi. Secara umum, S. laevis menyebar di Semenanjung Myanmar, Thailand, Semenanjung Malaysia, dan Indonesia (Sumatera dan Kalimantan). Penelitian ini menggunakan cpDNA dengan penanda mikrosatelit dan diamati alel serta lokus polimorfiknya yang bertujuan untuk mengetahui distribusi haplotipe cpDNA S. laevis di Kalimantan dan menduga keragaman cpDNA di dalam dan antar populasi S. laevis. Hasil analisis cpDNA berdasarkan penanda mikrosatelit terdapat empat multilokus haplotipe, yaitu A, B, C, dan D. Dua multilokus haplotipe ditemukan pada populasi Sari Bumi Kusuma dan dua multilokus haplotipe ditemukan di populasi ITCIKU. S. laevis memiliki nilai keragaman genetik (He) antara 0,046 - 0,128 dan nilai diferensiasi genetika (Gst) = 0,545. Hubungan kekerabatan terjauh dimiliki oleh populasi Sarpatim dengan Sari Bumi Kusuma, sedangkan populasi dengan jarak genetik terdekat adalah antara populasi Berau, Batu Ampar, Suka Jaya Makmur dan Bukit Bangkirai.
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Judul: Variasi DNA Kloroplas Shorea spp (Shorea acuminata Dyer, Shorea leprosula Miq dan Shorea parvifolia Dyer) Berdasarkan Penanda Mikrosatelit.
Abstrak: Shorea acuminata, Shorea leprosula, and Shorea parvifolia are members of the Diptecarpaceae family. They are ecologically and commercially important in the Southeast Asia region. In this present study, we used chloroplast microsatellites (cpSSR) to study the variation within and among Shorea species populations and the distribution of chloroplast DNA haplotypes of Shorea species. Based on chloroplast microsatellite analysis, the following diagnostic haplotypes were detected; namely haplotype A, C, and D for S. leprosula, S. parvifolia, and S. acuminata, respectively. In general, haplotype variation of cpSSR was low in this studies. The highest within population variation of cpSSR was observed in S. acuminata. The highest genetic differentiation was detected in S. parvifolia (Gst = 0.58) followed by S. acuminata (Gst = 0.31) and S. leprosula (Gst = 0.14). The haplotypes distribute evenly among different populations and between islands, and do not correspond with geographical separation among populations and islands. Some haplotypes from one species were shared by other species, indicating the possibility of gene flow via interspecific hybridization, that occurred currently and/or in the past. Introgressive hybridization probably occurred among Shorea species due to co-existance in the forest stands and overlapping flowering times.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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