Judul: Perbandingan Nilai Tengah Nomor Somaklon Jahe (Zingiber officinale Rosc.) dengan Menggunakan Uji Lanjut Scott-Knott
Abstrak: Ginger (Zingiber officinale Rosc.) is a herb plant used for herbal medicine, food and drink ingredient. Major obstacle that has been disrupting ginger production is bacterial wilt disease. Efforts are most effective and efficient to solve these problem is using tolerant varieties. Balai Penelitian Tanaman Rempah dan Obat (Balittro) as a research institution of spices and medical plants has been doing a research to obtain tolerant varieties. Tolerant varieties were obtained from ginger’s somaclones which tolerant to bacterial wilt disease. Five somaclone populations, FA, FB, AC1, AC2, and Fipla were tested the resistance to bacterial wilt disease. Research conducted on three response variables, namely the intensity of the disease, the appearance of the plants index (IPT) of growth variables, and IPT of production variables. The objectives of this study were to group the treatment means of ginger’s somaclones number with Scott-Knott test and to identify the characteristics of the three response variables. Scott-Knott test further showed red ginger’s number (CJ2.8B) is the most tolerant to bacterial wilt disease by the percentage intensity mean 19.65%. Ginger’s somaclone number AC1.39B has the best growth with mean IPT of growth variables 12.99. Ginger’s somaclone number AC1.19B has the highest productivity with mean IPT of production variables 18.36. Based on the classification of three grouping response variables, AC1.19B is the best and tolerant ginger somaclone number.
Keyword: Scott-Knott test, intensity of bacterial wilt disease, ginger’s somaclone number, appearance of the plants index (IPT)

Judul: Kendali Mutu Jahe Menggunakan Sidik Jari Kromatografi Cair Kinerja Tinggi dan Analisis Multivariat
Abstrak: Ginger is known to have pharmacology effect such as antioxidant, antiinflamation, and anticancer. The rhizome of ginger is widely used as component in various herbal medicine preparations so that needed some methods to guarantee its quality and pharmacology effect. The aim of this research was to evaluate the quality of gajah ginger rhizome by antioxidant activity assay, high performance liquid chromatography (HPLC) fingerprint pattern examination, major compound content determination, and also quality model establishment of ginger ethanol extracts from 3 areas, that is Ponorogo, Tangerang, and Bogor. All samples were indeed potential as very strong antioxidant. The result of HPLC analysis showed 6-, 8-, and 10-gingerol, also 6-shogaol as dominant compounds. Grouping based on content of dominant compounds and HPLC fingerprint that used principal component analysis resulted group I (Tangerang), group II (Ponorogo), and group III (Bogor). The quality model that was formed using partial least square discriminant analysis showed that antioxidant activity of ginger was more defined by composition of all compounds than by its dominant compounds.
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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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