Judul: Characterization of DGAT1 Gene as Candidate Marker for Quality and Nutrition of Indonesian Sheep
Abstrak: Kualitas daging domba premium melalui peningkatan nilai gizi yang terkandung dalam daging melalui potensi gen diacylglycerol acyltransferase-1 (DGAT1). Penelitian ini bertujuan mengidentifikasi keragaman gen DGAT1 pada SNP g.8539 C>T serta kaitannya dengan perbaikan kualitas dan gizi (flavour dan odour, asam lemak, kolesterol, mineral, dan karakteristik karkas) daging domba Indonesia. Total sampel domba yang digunakan keragaman gen DGAT1 254 sampel berumur 10–12 bulan dengan jenis kelamin jantan yang terdiri dari domba ekor gemuk (DEG) (n=20), domba ekor tipis (DET) (n=107), domba komposit garut (DKG) (n=10), domba compass agrinak (DCA) (n=10), domba barbados cross (DBC) (n=10), domba garut (DG) (n=20), domba jonggol (DJ) (n=27) dan domba lokal jambi (DLJ) (n=50). 100 sampel digunakan untuk asosiasi gen DGAT1 terhadap flavour dan odour, asam lemak, kolesterol, mineral, dan karakteristik karkas. Identifikasi keragaman DGAT1|ALuI dianalisis dengan metode PCR-RFLP. Hasil keragaman gen DGAT1 bersifat polimorfik dalam DET, DG, dan DEG, sedangkan DCA, DBC, DLJ, dan DKG bersifat monomorfik. Dua genotipe CC, dan CT ditemukan dalam DET, DG, dan DEG. Titik mutasi gen DGAT1 berasosiasi (P<0.05) pada flavour dan odour, asam lemak sedangkan titik mutasi gen DGAT1 tidak berasosiasi (P>0.05) pada kolesterol, mineral, dan karakteristik karkas. Gen DGAT1 memiliki kontribusi dalam flavour dan odour yaitu pada senyawa 4-Ethyloctanoic acid (EOA) serta pada konten lemak, asam palmitoleat, dan asam heptadekanoat, The quality of premium sheep meat through improving the nutritional value contained in the meat through the potential gene diacylglycerol acyltransferase-1 (DGAT1). This study aims to identify the diversity of the DGAT1 gene with SNP g.8539 C>T access number EU178818 and its relationship to the quality and nutritional value (mineral, cholesterol, flavour and odour, fatty acids, and carcass characteristics) of Indonesian sheep. A total of 254 samples and ages 10-12 months, consisted of javanese fat-tail sheep (JFTS) (n=20), javanese thin-tail sheep (JTTS) (n=107), garut composite sheep (GCS) (n=10), compass agrinak sheep (CAS) (n=10), barbados cross sheep (BCS) (n=10), garut sheep (GS) (n=20), jonggol sheep (JS) (n=27), and jambi local sheep (JLS) (n=50). 100 samples use association DGAT1 gene with mineral, cholesterol, flavour and odour, fatty acid, and characteristic carcass. The diversity of DGAT|AluI were analyzed with PCR-RFLP method. DGAT1 gene were polymorphic in JTTS, GS, and JFTS, and monomorphic in CAS, BCS, JLS, and GCS sheep population. Two type genotypes CC and CT were found in JTTS, GS, and JFTS. SNP g.8539 C>T in DGAT was associated to flavour and odour (P<0.05), and fatty acid, but it was not associated to cholesterol, mineral, and characteristic carcass. DGAT1 gene has contribution to level of flavour and odour through stimulate 4-Ethyloctanoic acid (EOA) molecules and fat content, palmitoleac acid, and heptadecanoat acid.
Keyword: sheep, DGAT1 gene, mineral, cholesterol, flavour and odour, fatty  acid, characteristic carcass, PCR-RFLP.

Judul: Characterization of CYP2E1 and HSD17β13 Gene as Candidate Marker for Improvement of Indonesian Lamb Quality
Abstrak: Gen CYP2E1 dan HSD17β13 merupakan salah satu kandidat gen yang diduga berperan dalam mengontrol kualitas daging domba. Penelitian ini bertujuan melakukan karakterisasi gen CYP2E1 dan HSD17β13 dengan tujuan untuk perbaikan kualitas daging tujuh jenis domba Indonesia, yaitu domba compass agrinak (DCA), domba barbados cross (DBC), domba komposit garut (DKG), domba garut (DG), domba ekor gemuk (DEG), domba ekor tipis (DET), dan domba jonggol (DJ). Karakterisasi gen dilakukan dengan tiga tahapan, yaitu melakukan identifikasi keragaman gen CYP2E1 (g 50.657.948 T>G) dan HSD17β13 (g 101.689.913 C>T) dengan menggunakan metode Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP), melakukan asosiasi gen CYP2E1 dan HSD17β13 dengan kualitas daging menggunakan uji T-test, serta menganalisis ekspresi gen CYP2E1 dan HSD17β13 dengan menggunakan Quantitative Real Time PCR (qRT-PCR). Hasil penelitian menunjukkan bahwa gen CYP2E1 dan HSD17β13 bersifat polimorfik yang ditandai dengan adanya tiga macam genotipe pada gen CYP2E1 (GG, GT, dan TT) dan HSD17β13 (CC, CT, dan TT). Keragaman genotipe gen CYP2E1 dan HSD17β13 tidak berada dalam kesetimbangan Hardy-Weinberg. Hasil analisis menunjukkan bahwa gen CYP2E1 (g 50.657.948 T>G) secara nyata berasosiasi (P<0,05) dengan kualitas daging seperti pH, keempukan daging, komposisi asam lemak (asam lemak tak jenuh tunggal seperti asam elaidik (C18:1n9t) dan asam lemak tak jenuh ganda seperti asam linoleat (C18:2n6c)), serta kandungan flavor dan odor, yaitu 3-methylindole (skatole). Domba dengan genotipe GG memiliki nilai kualitas daging yang lebih baik dibandingkan genotipe GT dan TT untuk sifat fisik daging dan komposisi asam lemak. Gen HSD17β13 (g 101.689.913 C>T) berasosiasi (P<0,05) dengan komposisi asam lemak, seperti asam lemak jenuh (asam arakidat (C20:0), asam henekosanoat (C21:0)), asam lemak tak jenuh, yaitu asam lemak tak jenuh tunggal (MUFA) seperti asam lemak ginkgoleat (C17:1) dan asam lemak tak jenuh ganda (PUFA) yaitu asam eikosedienoat (C20:2). Daging domba dengan genotipe CT memiliki nilai asam lemak tak jenuh yang lebih tinggi dibandingkan genotipe lainnya. Analisis ekspresi gen CYP2E1 menunjukkan adanya perbedaan yang nyata (P<0,05) antar genotipe. Genotipe GG memiliki tingkat ekspresi tertinggi di antara genotipe lainnya. Di lain pihak gen HSD17β13 tidak menunjukkan level ekspresi yang berbeda (P>0,05) antar genotipenya. Hasil penelitian ini menunjukkan bahwa gen CYP2E1 dan HSD17β13 dapat dijadikan sebagai kandidat marker dalam program seleksi domba untuk memperbaiki kualitas daging., CYP2E1 and HSD17β13 genes are candidate genes that play important role in controlling the lamb quality. This study aims to characterize the CYP2E1 and HSD17β13 genes in order to improve the quality of lamb of seven Indonesian sheep, namely compass agrinak sheep (DCA), barbados cross sheep (DBC), garut composite sheep (DKG), garut sheep (DG), fat tailed sheep (DEG), thin-tailed sheep (DET), and jonggol sheep (DJ). Gene characterization was carried out in three stages, namely identifying the diversity of CYP2E1 (g 50.657.948 T>G) and HSD17β13 (g 101.689.913 C>T) genes using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method, associated CYP2E1 and HSD17β13 genes with meat quality using the T-test, and analyzed the expression of CYP2E1 and HSD17β13 genes using Quantitative Real Time PCR (qRT-PCR). The results showed that the CYP2E1 and HSD17β13 genes were polymorphic which was indicated by the presence of three genotypes in the CYP2E1 (GG, GT, and TT) and HSD17β13 (CC,
Keyword: CYP2E1 gene, HSD17β13 gene, meat quality, PCR-RFLP, sheep

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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