Judul: Persistensi Cacing Endoparasit Gnathostoma Sp. Pada Belut Sawah Monopterus Albus Dan Pengendaliannya Menggunakan Mebendazole Dan Ekstrak Batang Pisang Ambon Musa Paradisiaca
Abstrak: Belut merupakan ikan konsumsi air tawar yang memiliki nilai gizi baik, namun belut menjadi inang antara cacing Gnathostoma sp. yang bersifat zoonosis, sehingga dapat menimbulkan masalah pada konsumen. Penelitian ini bertujuan menginventarisasi keberadaan cacing Gnathostoma sp. pada belut sawah di Jawa Barat dan mencari konsentrasi yang tepat dalam mengendalikan cacing Gnathostoma sp. menggunakan mebendazole 500 mg dan ekstrak batang pisang ambon melalui metode perendaman. Perendaman cacing secara in vitro, baik dalam larutan mebendazole maupun ekstrak batang pisang ambon menunjukkan bahwa semakin tinggi konsentrasi larutan maka kematian cacing semakin cepat. Hasil penelitian menunjukkan perendaman secara in vitro menggunakan bahan aktif mebendazole mengakibatkan kematian lebih cepat yaitu 2-3 hari dan ekstrak batang pisang ambon 6-7 hari, sedangkan perendaman dalam larutan fisiologis (tanpa pemberian mebendazole dan ekstrak batang pisang ambon) cacing mati 11- 12 hari.
Keyword: Belut sawah, Gnathostoma sp, in vitro, mebendazole, Musa paradisiaca

Judul: Efektivitas ekstrak batang Pisang Ambon Musa paradisiaca untuk pengendalian infeksi Saprolegnia sp. pada larva Ikan Gurame Osphronemus gouramy
Abstrak: Fase larva ikan gurame merupakan masa kritis terhadap infeksi cendawan, seperti cendawan jenis Saprolegnia sp. Beberapa tanaman memiliki daya antiseptik seperti tanaman pisang ambon. Penelitian ini bertujuan untuk menguji efektivitas ekstrak batang pisang ambon (Musa paradisiaca) dalam mengurangi infeksi Saprolegnia sp. pada larva ikan gurame (Osphronemus gouramy) melalui media pemeliharaan. Larva gurame umur 8 hari (panjang larva 0,5+0,03 cm) dipelihara pada akuarium berukuran 25x25x25 cm dengan padat tebar 8 ekor/L. Media pemeliharaan diberi ekstrak batang pisang ambon dosis 0; 0,08; 0,12 dan 0,16 g/L selama 25 hari. Uji tantang dilakukan selama 14 hari dengan pemberian spora Saprolegnia sp. kepadatan 104 sel/mL dan tetap diberi ekstrak batang pisang ambon selama masa uji tantang berlangsung. Perlakuan dosis 0,16 g/L memberikan kelangsungan hidup sebesar 100% yang lebih tinggi dibandingkan perlakuan kontrol positif setelah uji tantang., Larvae stage of giant gouramy is a critical period due to fungal infection, like Saprolegnia sp infection. There are some plants have antiseptic compound like banana (Musa paradisiaca). This research aims to examine the effectiveness of the banana stem extract (Musa paradisiaca) to reduce the infection of Saprolegnia sp. on giant gouramy larvae through immersion. Eight-day old gouramy larvae (0.5±0.03 cm length) were reared in an aquarium measuring 25x25x25 cm with density 8 fry/L. Rearing media were given banana stem extract 0; 0,08; 0,12; and 0,16 g/L doses during 25 days. Challenge test performed during 14 days which infection of Saprolegnia sp. with spore density 104 cells/mL given and still given banana stem extract during chalange test. The treatment dose of 4% gives 100% survival at the higher compared positive control after the challenge test.
Keyword: Osphronemus gouramy, Musa paradisiaca, Saprolegnia sp., larva

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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