Judul: Identifikasi Keragaman Gen Alpha-S1 Casein g.12164G>A pada Kambing Perah di Balitnak
Abstrak: Polimorfisme gen Alpha-S1 Casein (CSN1S1) berimplikasi pada keragaman komposisi susu dan kualitas curd keju. Penelitian dilakukan untuk mengidentifikasi keragaman gen CSN1S1 g.12164G>A, berasal dari 67 set DNA terdiri dari kambing PE 5 ekor, saanen 8 ekor, Sapera 51 ekor, dan SaanPE 3 ekor di Balitnak. Polimorfisme diidentifikasi menggunakan PCR-RFLP enzim DdeI standar Phenol-chloroform. Keragaman gen dianalisis menggunakan program Popgen32. Amplifikasi menghasilkan panjang fragmen 438 bp. Enzim DdeI memotong produk PCR menjadi 3 fragmen, yakni 192 pb, 145 pb, dan 101 pb, dinyatakan sebagai alel G, sedangkan alel A apabila terpotong menjadi 2 fragmen, yaitu 337 pb dan 101 pb. Frekuensi alel G tertinggi terdapat pada kambing saanen (0.625), Sapera (0.578), PE (0.400) dan terendah SaanPE (0.333). Frekuensi alel A tertinggi terdapat pada kambing SaanPE (0.667), PE (0.600), Sapera (0.422) dan terendah pada kambing saanen (0.375). Keragamaan tertinggi terdapat pada kambing saanen (0.75). Sebagian besar kambing perah pengamatan berada dalam kesetimbangan Hardy-Weinberg, terkecuali kambing SaanPE. Berdasarkan data keragaman, dapat disimpulkan bahwa kambing perah di Balitnak Ciawi bersifat polimorfik untuk gen CSN1S1 g.12164G>A
Keyword: gen CSN1S1, kambing perah, PCR-RFLP, polimorfisme

Judul: Identifikasi keragaman gen β-Kasein (CSN2) pada kambing peranakan etawah, saanen dan persilangannya dengan metode PCR-SSCP
Abstrak: Casein genetic polymorphisms are important and well known due to their effects on quantitative traits and properties of milk. β-kasein gene is directly related to the quality and properties of milk. A protocol for the rapid and simultaneous genotyping of β-kasein alleles was conducted by single strand conformational polymorphism polymerase chain reaction (SSCP-PCR) method in goat. Screening β-kasein gene variability in 3 dairy goat breeds was conducted for Etawah Grade (77 samples), Saanen (67 samples) and PESA (Crossbreed Etawah Grade with Saanen) (29 samples) in Bogor and Sukabumi. The objective of this research was to identify polymorphism of the β-kasein (CSN2) gene in dairy goat. This research found three alleles of the β-casein gene, ie CSN2*A, CSN2*C, dan CSN2*O. In most breeds, CSN2*O occurred in the lowest frequency. The identification of the CSN2 gene variability in the goat breeds indicated the highly of the A allele. The CSN2*A allele had a high frequency in Saanen in Cijeruk (0,66); Etawah Grade in Cariu (0,62); and PESA in Cariu (0,54). While the CSN2*C allele had a high frequency in PESA in Balitnak (0,83); Etawah Grade in Ciapus (0,48); and Saanen in Taurus (0.38). Based on the results of chi-square analysis, found that Saanen in Cariu and Taurus were not in Hardy-Weinberg equilibrium.
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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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