Judul: Growth and Methane Oxidation Activity of Methanotrophic Bacteria in Different Media
Abstrak: Methanotrophs are bacteria that can utilize methane or C1 compounds as their sole carbon and energy source. Previous study resulted that BGM 1, BGM 3, BGM 9, and SKM 14 isolates could oxidized CH4. Objective of this research was to formulate medium composition for production of methanotrophic bacteria. The substances that we used as carbon sources were methanol, mollase. And a nitrate was as a nitrogen source. Specific growth rate of bacteria in methanol and nitrate was different for each isolate. The best carbon and nitrogen sources of medium for bacterial growth was methanol 2% and nitrate 1 g/L. Methane oxidation rate of BGM 1, BGM 3, BGM 9, and SKM 14 isolates was 0.01, 0.04, 0.03, and 0.03 mol/ml culture/day respectively. The highest activity of methane oxidation was perfomed by BGM 3 isolate, and the highest ammonium accumulation was perfomed by BGM 9 isolate. The bacterial cells produced by medium of combination methanol 2% and nitrate 1 g/L were tested in soil of a rice field in laboratorium scale. The result showed that methane concentration was decreased in twelveth days of incubation. The methane reduction activity of the isolates during incubation of 8 to 12 days was 88.5%, 85.1%, 47.8%, and 66.4% for BGM 1, BGM 3, BGM 9, and SKM 14 isolates respectively.
Keyword: 

Judul: Aktivitas Oksidasi Metan dan Reduksi Dinitrogen Oksida (N2O) Kultur Kombinasi Bakteri Metanotrof dan Ochrobactrum anthropi
Abstrak: Methane Oxidation and Nitrous Oxide (N2O) Reduction Activity on Combination Culture of Methanotrophic Bacteria and Ochrobactrum anthropi. Under supervision of IMAN RUSMANA and ALINA AKHDIYA. Rice fields are one source of methane (CH4) and nitrous oxide (N2O) emission. Methanotrophic bacteria and denitrifying bacteria possesing high methane oxidation and N2O reduction activity are very important for controlling CH4 and N2O emission from rice fields. This research was conducted to test the activity of methane oxidation and N2O reduction from four methanotrophic bacteria (BGM 1, BGM 5, BGM 9, and SKM 14 isolates) and two Ochrobactrum anthropi isolates (BL 1 and BL 2 isolates). Six combination were inoculated into Nitrate Mineral Salt (NMS) media mixed with denitrification media, then the activity of methane oxidation, N2O reduction, accumulation of ammonium, nitrite, and nitrate was analyzed. Combination culture E of BGM 1, SKM 14, BL 1, and BL 2 isolates had the highest CH4 oxidation (2,9 x 10-8 ìM/cell/day), N2O reduction activities (0,15 x 10-9 ìM/cell/day), and accumulation of ammonium (19,3 x 10-8 ìM/cell/day) than the other combination cultures. Combination culture of BGM 1, SKM 14, and BL 1 isolates had the highest accumulation of nitrate (17,6 ìM) and combination culture of BGM 5, BGM 9, BL 1, and BL 2 isolates had the highest accumulation of nitrite (10,9 ìM).
Keyword: 

Judul: Penetapan Harga Jaminan Polis Asuransi Jiwa dengan Premi  Tahunan dan Opsi Surrender
Abstrak: Asuransi jiwa memberikan perlindungan pada tertanggung (pemegang polis) jika mengalami risiko finansial, dengan suatu perjanjian tertanggung harus membayar premi. Premi yang sudah terkumpul pada perusahaan asuransi dapat diinvestasikan, yang salah satu tempatnya adalah di pasar bursa. Perusahaan asuransi menawarkan suatu kontrak kepada pemegang polis yang disebut dengan kontrak partisipasi. Pada kontrak partisipasi risiko finansial dan keuntungan dibagi dengan pemegang polis dan biasanya keuntungan tersebut dimasukkan ke dalam cadangan polis pada tiap akhir tahun kontrak. Hal ini berarti secara tidak langsung perusahaan asuransi menyatakan penambahan pertanggungan, sehingga mengakibatkan perubahan benefit yang diterima oleh pemegang polis. Pada kontrak partisipasi ini, pemegang polis diberikan hak untuk mengakhiri kontrak (opsi surrender). Pada kontrak partisipasi asuransi jiwa endowmen terdapat opsi bonus (bonus option) yang penghitungan besar preminya dengan pendekatan tipe Eropa dan opsi surrender (surrender option) dengan tipe Amerika.
Keyword: