Judul: Identifikasi SNP Promotor Gen MC1R pada Sapi Bali Menggunakan Metode Direct Sequencing
Abstrak: Sapi Bali memiliki warna rambut kemerahan pada betina dan hitam pada jantan, adapun abnormalitas yang muncul adalah albino. Gen MC1R memengaruhi warna rambut sapi Bali melalui SNP, yaitu perubahan satu basa nukleotida yang terlihat dalam hasil sequencing. Penelitian ini bertujuan untuk mengidentifikasi SNP pada promotor gen MC1R dan menganalisis hubungannya dengan warna rambut normal dan albino pada sapi Bali. Penelitian dilakukan di Laboratorium Genetika Molekuler, Fakultas Peternakan IPB. Jumlah sampel sebanyak 24 sampel sapi terdiri dari 11 sampel sapi warna rambut normal dan 13 sampel sapi warna rambut albino berasal dari UPTD Sobangan dan Desa Taro, Kabupaten Gianyar, Provinsi Bali. Identifikasi SNP promotor gen MC1R menggunakan metode direct sequencing dengan panjang sekuen target 559 bp. Hasil sekuen gen MC1R dianalisis menggunakan program MEGA11, BioEdit, dan FinchTV. Hasil identifikasi promotor gen MC1R ditemukan SNP g.105 G>A. Keragaman hanya pada sapi Bali warna rambut normal, sedangkan pada sapi Bali warna rambut albino seragam. Demikian disimpulkan bahwa promotor gen MC1R pada sapi Bali tidak dapat digunakan sebagai marker untuk membedakan sapi normal dan albino berdasarkan warna rambut., Bali cattle have a reddish hair in females and black in males, with an abnormality being albino. The MC1R gene affects the hair color of Bali cattle through SNP, which are changes in one nucleotide base visible in sequencing result. This study aimed to identify SNP in the MC1R gene promoter and analyse their association with normal and albino hair color in Bali cattle. The research was conducted at the Laboratory of Molecular Genetics, Faculty of Animal Science, IPB. There were 24 cattle samples consisting of 11 normal hair color cattle samples and 13 albino hair color cattle samples from UPTD Sobangan and Taro Village, Gianyar Regency, Bali Province. Identification of MC1R gene promoter SNP using direct sequencing method with a target sequence length of 559 bp. The MC1R gene sequence results were analysed using MEGA11, BioEdit and FinchTV programs. The result of MC1R gene promoter identificatoin found SNP g.105 G>A. Diversity is only in normal hair color Bali cattle, while in albino hair color Bali cattle are uniform. Thus it is concluded that the MC1R gene promoter in Bali cattle cannot be used as a marker to distinguis normal and albino cattle based on hair color.
Keyword: direct sequencing, gen MC1R, sapi bali, SNP, warna rambut

Judul: Identification of SNPs in Exon 17 of the Receptor Tyrosine  Kinase (KIT) Gene in Bali Cattle
Abstrak: Menurut Standar Nasional Indonesia (SNI), sapi bali jantan umumnya memiliki rambut berwarna merah atau hitam, sedangkan betina memiliki warna rambut merah. Setiap penyimpangan dari warna tersebut menunjukkan adanya kelainan pada warna rambut sapi bali. Gen KIT diketahui memengaruhi warna rambut sapi bali. Penelitian ini bertujuan untuk mengidentifikasi apakah terdapat SNP pada gen KIT yang dapat menyebabkan warna rambut albino pada sapi bali menggunakan metode direct sequencing. Analisis PCR dilakukan pada suhu annealing 61 °C dan hasil produk PCR dikirim ke laboratorium 1st Base di Selangor, Malaysia untuk analisis sekuensing, data sekuensing dianalisis menggunakan MEGA10 2.6, FichTV, dan BioEdit 7.2. Hasil sekuensing pada gen KIT ekson 17 menunjukkan tidak ada SNP pada sapi bali normal dan albino. Kesimpulannya, gen KIT ekson 17 bersifat monomorfik sehingga tidak dapat dijadikan sebagai penanda yang membedakan warna rambut normal dan albino pada sapi bali., According to the Indonesia National Standard (SNI), male bali cattle typically have dark reddish or blackish hair, while females exhibit a reddish hair color. Any deviation from these colors indicates an abnormality in the bali cattle’s hair color. The KIT gene is known to influence the hair color of bali cattle. This research aims to identify whether there are SNPs in the KIT gene that can result in albino hair coloration in Bali cattle using direct sequencing methods. PCR analysis was conducted at an annealing temperature of 61 °C, and the PCR product outcomes were sent to the 1st Base laboratory in Selangor, Malaysia for sequencing analysis, the sequencing data were analyzed using the MEGA10 2.6, FinchTV, and BioEdit 7.2. The sequencing result of the KIT gene exon 17 shows no SNPs in normal and albino bali cattle. In conclusion, the study found that the KIT gene exon 17 is monomorphic and therefore cannot be used as a distinguishing marker for normal and albino hair coloration in bali cattle.
Keyword: albino, bali cattle, exon 17, KIT gene, SNPs

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.
Keyword: