Judul: Keragaman Genetik Aksesi Pinang (Areca catechu L.) Asal Papua, Sulawesi Utara, dan Sumatera Utara Berdasarkan Karakter Morfologi dan Penanda RAPD (Random Amplified Polymorphic DNA)
Abstrak: Areca nuts (Areca catechu L.) is a palm plant that has not been studied intesively than other palm crops (coconut). Areca nuts is used as ingredients of medicines, cosmetics, and ceremonial, as well as a symbol of social and cultural relationship. The objectives of these studies were to explore genetic diversity of areca nuts accessions (Areca catechu L.) from Papua, North Sulawesi and North Sumatera that were collected and planted in Experimental Station Kaiwatu, Indonesian Coconut and Palmae Research Institute (Balitka), Manado. These studies were conducted in July 2010 - June 2011. Plant morphological characters were observed and measured and DNA markers were identified using two primers RAPD. Data were analyzed using the program NTsys 2.02. Morphological characters for eight accessions of areca nuts has a similarity level 6%. However, the similarity of six areca nuts accessions, representing three provinces, based on DNA markers was 49%. Individual areca nuts palms are not groupped into their accession, based on either morphological or DNA markers.
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Judul: Kemiripan genetik populasi kelapa dalam mapenget, tenga, Bali, Palu, dan sawarna berdasarkan penanda RAPD (Random Amplified Polimorphic DNA)
Abstrak: A study of genetic similarity in coconut by RAPD analysis was performed in 50 individuals representing 5 tall coconut populations namely Mapanget Tall (DMT). Tenga Tall (DTA), Bali tall (DBI), Palu Tall (DPU), and Sawarna Tall (DSA), showed polymorphic bands with all 10 primers tested. A total of 91 RAPD bands were scored with 87 polymorphic bands (95%). A high level within-populations (13% - 22%). Improved character by selection in DMT, DTA, and DSA populations must be done carefully in individual palm which still high enough genetic distance, but in DBI and DPU populations it still have a good possibility.
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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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