Judul: Identifikasi Keragaman Genetik Gen Reseptor Hormon Pertumbuhan (GHR|AluI) pada Sapi Bali:
Abstrak: One of factor affects in growing is Growth Hormone Receptor (GHR). GHR is required for GH to carry out its effects on target tissues. The objective of the study was to estimate genetic diversity of the GHR|AluI in Bali, Limousin, Simmental and Pesisir cattle. Genotyping was performed on 248 animals, including 162 Bali, 21 Limousin, 17 Simmental and 48 Pesisir cattle breeds. Single Nucleotide Polymorphisms (SNP) has been found in exon 10, coding for the cytoplasmic domain of GHR, which was located at position 81 bp (A/G) induce amino acid substitutions Ser/Gly. Genotype frequencies of Bali cattle AA (0.988), GG (0.006) and AG (0.006) were evidenced for the GHR|AluI monomorphism, but largerly different from Limousin GG (0.667), AA (0.238) and AG (0.095), Simmental AG (0.529), GG (0.471) and AA (0.000), Pesisir AA (0.604), GG (0.375) and AG (0.021) were the evidenced of polymorphism. It was suggested that homozigosity (monomorphism) in Bali cattle could be affected by adaptability in extreme environmental conditions such as poor nutrition and improper manajement practice. It also could be affected by natural selection and phenotype plasticity phenomena.
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Judul: Identifikasi keragaman Gen Growth Hormone Receptor (GHR AluI) pada Sapi Friesian Holstein di BIB Lembang, BBIB Singosari, dan BET Cipelang.
Abstrak: Growth hormone receptor (GHR) is one factor affecting animal growth. GHR is required by growth hormone (GH) to carry out its effect on target tissues. The objective of this study was to identify polymorphism of the Growth Hormone Receptor gene in Holstein Friesian (HF) dairy cattle and beef cattle. Genotyping was performed on 126 animals. These consisted of HF 89 heads from BIB Lembang (17), BBIB Singosari (32), and BET Cipelang (40); as well as for 37 heads of four breeds of beef cattle including for Simmental (13), Limousin (14), Brahman (5), and Angus (5) for a comparison. Varian genetic of the GHR gene was identified by PCR-RFLP method using AluI restriction enzyme cutting the base position at AG|CT. Single nucleotide polymorphism (SNP) had been found in exon 10, coding for the cytoplasmic domain of GHR, which was located at position 81 bp (A/G) induced amino acid substitutions Ser/Gly. The product of amplification of GHR was 298 bp. Genotyping the GHR gene produced two alleles (A and G) resulting three genotypes (AA, AG and GG). The genotype AA was dominant in HF cattle from all locations, and also in Brahman and Limousin cattle from BET Cipelang. All of HF dairy cattle were in Hardy-Weinberg disequilibrium (χhit 2>χ0,05 2), in contrast, Simmental and Limousin were in Hardy-Weinberg equilibrium. The Hardy-Weinberg in Brahman and Angus values could not be calculated. Heterozigosity values in HF and beef cattle were low (ho<he). In beef cattle, Angus had highest heterozigosity value (0,600), while Brahman had the lowest heterozigosity value (0.000). The conclusion was that the variability of GHR|AluI gene can be used as a basic information for selection in growth caracteristic in the HF and beef cattle. Keywords: Beef cattle, Genetic polymorphism, GHR|AluI gene,
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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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