Judul: Pertumbuhan, Produksi Biomassa Daun, dan Struktur Sekretori Sambiloto (Andrographis paniculata Nees.) pada Perlakuan Naungan dan Pupuk Organik
Abstrak: Sambiloto (Andrographis paniculata Nees.) is a medicinal plant which can be cultivated under the forest stands. Growth, leaves biomass production of sambiloto could be influenced by shade and soil nutrient. Therefore, it is important to measure growth, leaves biomass production, and secretory structure under shade and organic fertilizer. This study used split plot randomized complete design with two factors i. e. shade and type of organic fertilizer. The observed parameters including shoot and root growth. The results showed that the goat manure and chicken manure medium under unshaded condition can improve plant growth and leaves biomass of sambiloto. Total leaf area, leaf, stem, and roots dry weight were influenced by shade, organic fertilizer, and the interaction of both shade and organic fertilizer. The secretory cell structure of sambiloto was not affected by the interaction between shade and organic fertilizer treatment.
Keyword: shade, secretory cell structure, sambiloto, organic fertilizer

Judul: Pengaruh intensitas naungan dan kombinasi pemupukan N dan P terhadap pertumbuhan, produksi simplisia serta kandungan andrographolida pada sambiloto [Andrographis paniculata]
Abstrak: Penelitian ini dilakukan untuk mengetahui pengaruh intensitas naungan dan kombinasi pemupukan N dan P terhadap pertumbuhan, produksi simplisia serta kandungan andrographolida pada sambiloto. Penelitian dilaksanakan pada bulan September 2008 - Februari 2009 di Kebun Percobaan IPB Sawah Baru, Darmaga. Penelitian ini menggunakan Rancangan Petak Terbagi dengan dua faktor yaitu perlakuan intensitas naungan dan kombinasi pemupukan N dan P. Petak utama adalah intensitas naungan yang terdiri atas tiga taraf yaitu 0, 25, dan 50%. Kombinasi dosis pupuk N dan P sebagai anak petak terdiri dari enam taraf yaitu 100 – 100, 150 – 100, 200 – 100, 150 - 150, 150 – 200, and 200 – 200 kg N – kg P2O5 per ha. Bahan yang digunakan adalah bibit sambiloto yang berasal dari biji, berumur 6 minggu, dan ditanam dengan jarak tanam 30 cm x 30 cm. Seluruh perlakuan diberikan pupuk kandang satu minggu sebelum tanam dengan dosis 20 ton/ha. Pupuk diberikan sesuai dengan perlakuan satu minggu setelah tanam (MST). Seluruh perlakuan diberikan pupuk KCl dengan dosis 150 K2O kg/ha. Aplikasi pemupukan kedua dan ketiga dilakukan pada waktu 11 dan 19 MST dengan setengah dosis N dari pemupukan pertama. Pemanenan dilakukan tiga kali yaitu pada 10, 18, dan 25 MST dengan cara dikepras setinggi 10 cm di atas permukaan tanah. Analisis kandungan andrographolida menggunakan alat HPLC (High Performance Liquid Chromatography).
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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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