Judul: Induksi pematangan gonad belut sawah monopterus albus dengan hormon gonadotropin 5IU, 10 IU dan 15 IU
Abstrak: Rice field eel is one of high demand commodity in the market, therefore hatchery efforts should be initiated to provide mature broodstock in the early development. This study used female rice field eel size of weight (14.252±1.346 g) with the induction of pregnant mareserum gonadotropin (PMSG) with dosage of 0 IU Control, 5 IU, 10 IU, 15 IU. Result indicates that the induction 10 IU of PMSG hormone can increase eel fish gonadosomatic index (GSI) value 0.9% in the fourth week, instead the highest Hepatosomatic index (HSI) value 5.303% in the second week of treatment. Maturing state is obtain from third week until at the end of treatment (fifth week). The highest spesific growth rate (SGR) for 0.025% came from 15 IU treatment and gonadal histology in the fifth week showed that the rice field eel has reached the maturing state. The impact of PMSG hormone can accelerate the maturity of rice field eel female gonads on the size of 14.252±1.346 g and length of 25.73 ± 0.253 cm can be applied as early in the development of semi-natural spawning rice field eel., Belut merupakan ikan dengan permintaan pasar yang terus meningkat sehingga perlu dukungan p embenihan untuk meningkatkan ketersediaan stok. Pengembangan pembenihan dimulai dengan penyediaan induk matang gonad. Pada penelitian ini dilakukan pematangan gonad betina (14,252±1,346g) dengan metode induksi hormon Pregnant mare serum gonadotropin(PMSG) pada dosis 0 (kontrol), 5 IU, 10 IU dan 15 IU. Hasil menunjukkan pemberian hormon tersebut pada dosis 10 IU meningkatkan Gonadosomatic Index (GSI) 0,9% pada minggu 4 dan Hepatosomatic index (HSI) 5,303% pada minggu 2. Tingkat kematangan gonad terjadi pada minggu 3 sampai dengan minggu 5. Spesific growth rate (SGR) tertinggi (0,025%) terjadi pada perlakuan dosis 15 IU dengan tahap maturasi pada minggu 5 yang dapat dilihat dari histologi gonad. Dapat disimpulkan hormon PMSG mempercepat kematangan gonad betina belut sawah dan merupakan pengembangan awal (invensi) untuk teknologi pemijahan semi alami belut sawah.
Keyword: 

Judul: Induksi Maturasi Belut Sawah (Monopterus albus) Secara Hormonal
Abstrak: Rice field eel (Monopterus albus) fish, often there is a failure in the process of and spawning. Rice field hormones Pregnan Mare Serum Gonadotropin (PSMG), human chorionic gonadotropin (hCG) and antidopamine (AD). maturation and determine the status sex completely randomized design (RAL) with seven treatments and seven as: Controls (0.95% NaCl of fish, AD 0.01 mg/kg of fish, PMSG 20 IU/kg+AD 0.01 mg mg/kg weight of fish. Aquarium used as many seven pieces with size cm. The result is best hormone combination treatme with hormone concentrations of estradiol 0.17 to 4.36%; HSI values maturity level TKG IV pregnancy rate 100%; contained in PMSG stimulates an increase FSH, estradiol caused performance of the enzyme aromatase process faster for 4 weeks, look at increasing GSI, H maturity, fecundity, body weight gain conclusion of this study is the induction of maturation eel rice can be done with PMSG 20IU+AD 0.01 mg/kg with a length of 22±2 cm results are females (mature) Keywords: Rice field eel, maturation, PMSG, hCG, antidopamine SUMMARY PUTRA. Hormonal Induction maturation of Rice albus). Guided AGUS OMAN SUDRAJAT and NUR are hermaphroditic protogynous. In the female final gonadal maturation, ovulation eel with a total length of 22±2 cm by inject This study aimed to induce gonadal of rice field eel. This study uses a reaply NaCl), PMSG 20 IU/kg weight of fish, hCG 20 IU/kg weight /PMSG 20 IU/kg+hCG 10 IU/kg weight of fish, mg/kg weight of fish, and hCG 20 IU/kg of treatment PMSG and antidopamin estradiol-17β 235.2 to 35.43 pg/ml; GSI values 2.07 to 3.52%; egg diameter 0.48 to 3.07 mm; gonad G IV; fecundity 128 eggs; length 0 cm; weights ; and sex status all female. This result because estradiol-17β concentration ormance so that affects vitellogenesis HSI, egg diameter, gonad was observed and sexual status injection for four weeks. Sex status of rice field eel and weight of about 5 g until 12 g hormonal induction mature).
Keyword: 

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: