Judul: Cytochrome oxidase subunit 1 (COI) gene variations in mitochondrial DNA of Apis koschevnikovi in South Kalimantan
Abstrak: Deforestasi di hutan Kalimantan yang berupa pembalakan dan konversi hutan menjadi perkebunan kelapa sawit menghancurkan habitat organisme dan ekosistem. Kondisi ini merupakan ancaman yang serius terhadap spesies asli yang berasal dari Kalimantan, termasuk Apis koschevnikovi (Hymenoptera; Apidae). Penelitian-penelitian sebelumnya menunjukkan kecendrungan populasi A. koschevnikovi yang terus menurun. Memelihara integritas ekologi A. koschevnikovi sangat diperlukan, termasuk database molekulernya. Sitokrom Oksidase subunit I (COI) di DNA mitokondria (DNAmt) dapat membantu dengan menyediakan penanda molekuler dengan teknologi berbasis DNA barcoding. Saat ini, telah ditemukan sebanyak 15 jenis haplotipe gen COI dari A. koschevnikovi yang telah dipublikasikan di Genbank. Tujuan dari penelitian ini adalah untuk mengetahui variasi genetik dari A. koschevnikovi Kalimantan Selatan berdasarkan gen COI dengan menggunakan metode sekuensing DNA. Contoh yang digunakan dalam penelitian ini berasal dari 5 kabupaten di Kalimantan Selatan; Hulu Sungai Selatan (HSS), Hulu Sungai Tengah (HST), Kotabaru (KB), Tanah Bumbu (TB), and Balangan (BL). Pengurutan nukleotida dari contoh yang digunakan menghasilkan panjang nukleotida sebanyak 738 bp, dan sebanyak 5 haplotipe dari nukleotida telah ditemukan. Haplotipe umum ditemukan dari contoh yang berasal dari Kabupaten HST dan TB. Hasil pengurutan dari contoh ini tidak menunjukkan kesamaan dengan 15 haplotipe dari Genebank, sehingga 5 haplotipe yang ditemukan dalam penelitian ini dapat disimpulkan sebagai haplotipe baru
Keyword: 

Judul: Cytochrome Oxidase Subunit I (COI) Gene Variations of Mitochondrial DNA of Apis cerana
Abstrak: Apis cerana is a native honey bee of Asia, ranging from China to the Philippines. Based on genetic a databases in GenBank of mitochondrial DNA Cytochrome Oxidase Subunit I (COI) A. cerana from Malaysia, Brunei, Thailand, Taiwan, Korea, Japan, and Russia occur nine haplotypes. However, there is no COI data haplotype of A. cerana from Indonesia. This study was aimed to explore haplotype variations of COI gene of A. cerana from Java, Lombok, Sumbawa and Flores. Collection and extraction of A. cerana DNA was carried out from those four islands. DNA extraction and amplification process were followed with DNA sequences of COI gene. This study revealed six new variations haplotypes A. cerana from Java, Lombok, Sumbawa and Flores Indonesia. Two haplotypes were seen each from Java and Flores as well as one haplotype each from Lombok and Sumbawa. All honey bee A. cerana in Java showed the same COI haplotype except for those samples from Cililin, West Java, this might be due to the isolation area of Cililin. Haplotypes variation in Lombok, Sumbawa, and Flores occured could be due to the isolation of these islands by sea. Alignment was performed on A. cerana COI sequences from the results of this study with GenBank database, showed that based on COI, honey bee A. cerana from Java, Sabah, and Brunei were closely related and clustered in the same group. This phenomena support the theory of the Asian unity mainland in the Pleistocene Era. Honey bee A. cerana COI haplotypes from Lombok, Sumbawa, and Flores were different from any other haplotypes. This might be due to in the Pleistocene Era, those islands were the emergen areas of a broad zone in shallow water
Keyword: 

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.
Keyword: