Judul: Agrobacterium tumefaciens-mediated transformation techniques in several plants
Abstrak: Genetic transformation is a process to introduce foreign gene from one organism to other organisms. This process is a site directed mutagenesis that can improve a good character without changing the existing characters. The use of Agrobacterium tumefaciens as a vector in genetic transformation has several advantages compared to other transformation techniques. It is a simple method, does not need special equipment, and produces high transformation efficiency in transfering a single copy of insert gene. This research is a comparative genetic transformation among several plants that have different characters. They are mangosteen as an apomixis plant, tobacco as a model plant, orchid as a monocotyledon plant, and coffee as a dicotyledon plant. The transformation were conducted in a same method and continued with regeneration step in antibiotic selectable medium. Gene insert confirmation using Polimerase Chain Reaction (PCR) technique showed that only tobacco the expected gene insert. The result suggested that the plant ability to grow in selective medium was not guaranteed as a transgenic plant before being confirmed using molecular assay approach. Some optimation in explants sterilization, infection techniques, number of transformed explants and tested transformed samples are required to be increases to achieve high transformation efficiency. Keyword : Agrobacterium tumefaciens-mediated transformation, transgenic plant.
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Judul: Teknik Transformasi Genetik beberapa Tanaman Menggunakan Agrobacterium tumefaciens
Abstrak: Transformasi genetik adalah proses introduksi gen dari satu organisme ke organisme lain yang memungkinkan untuk memunculkan sifat harapan tanpa mengubah sifat lain. Penggunaan Agrobacterium tumefaciens sebagai vektor transformasi memiliki keunggulan karena tidak membutuhkan peralatan khusus serta efisiensi transformasi dan salinan tunggal dari gen yang ditransformasi relatif tinggi. Penelitian ini merupakan penelitian transformasi komparatif pada beberapa tanaman yang memiliki karakter berbeda, yaitu manggis sebagai tanaman apomiksis, tembakau sebagai tanaman model, anggrek sebagai perwakilan dari kelas monokotil, dan kopi sebagai perwakilan dari kelas dikotil. Transformasi dilakukan dengan metode yang sama dan dilanjutkan dengan regenerasi pada media seleksi yang mengandung antibiotik. Konfirmasi sisipan gen hasil transformasi dilakukan dengan teknik Polimerase Chain Reaction (PCR). Hasil konfirmasi dari sampel tanaman yang mampu tumbuh pada media seleksi menunjukkan hanya tembakau yang positif tersisipi oleh gen yang ditransfomasi. Hal ini menunjukkan bahwa tanaman hasil transformasi yang mampu hidup di media seleksi belum merupakan jaminan tersisip oleh gen yang diintroduksi sebelum dilakukan pengujian molekuler. Beberapa optimasi dalam sterilisasi, teknik infeksi, peningkatan jumlah eksplan yang ditransformasi dan jumlah sampel yang diuji perlu dilakukan untuk peningkatan efisiensi transformasi.
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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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