Judul: Keragaman genetik kelapa genjah jombang berdasarkan  penanda RAPD (Random Amplified PoIymorphic DNA)
Abstrak: Information of genetic diversity in coconut (Cocos nucifera L.) is necessary to support the breeding programs and germplasm conservation efforts. RAPD is molecular marker can provide to enhance the efficiency of early selection for time consuming of coconut breeding. The objective of this research was to study the genetic diversity of Jombang dwarf coconut populations grown at Pakuwon and Mapanget Coconut Research Station (BALITKA) and at Jombang, and to identify RAPD markers of Genjah Merah Jombang (GMJ), Genjah Kuning Jombang (GKJ), Genjah Hijau Jombang (GHJ), and Genjah Coklat Jombang (GCJ) populations. DNA was amplified using Polymerase Chain Reaction (PCR) and ten random decamer primers. 92% of RAPD markers were polymorphic. Genetic diversity of coconut population in BALITKA was higher than that in Jombang. Genetic diversity within GMJ, GKJ, GHJ, and GCJ populations was 15, 15, 19, and 16% respectively, but among populations was 20%. 750 bp band has been identified from DNA bulk of GCJ coconut using OPA 18 primer. This DNA fragment need to be analyzed further whether could be used as spesific marker for GCJ coconut population.
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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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