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: Efektivitas Perendaman Benih Ikan Gurame Osphronemus goramy dengan Ekstrak Pelepah Pisang Ambon Putih Musa paradisiaca untuk Pengendalian Infeksi Bakteri Aeromonas hydrophila
Abstrak: The purpose of this research was to determine the effectivity of immersion treatment on Giant Gouramy fry Osphronemus goramy with white banana stem Musa paradisiaca extract in controlling infection of Aeromonas hydrophila. Effectivity test of banana stem extract against the infection of A. hydrophila was performed through two different tests, in vitro and in vivo. In vitro test consisted of inhibition zone test with treatment dosages of 5%, 10%, 20%, 25% and 50%. Diameter size of each treatments were not significantly different (P>0.05). In vivo test consisted of 4 treatments, negative control, positive control, preventive, and curative. For preventive and curative treatments, immersion with banana stem extract was also performed with dosages of 5% and 10%. The results that banana stem extract significantly (P<0.05) showed the survival rate as much as 48.12% in the preventive treatment. However, the effects of banana stem immersion are not significantly different in curative treatment because it was only able to increase the survival rate as much as 37.04%. Preventive treatment was effective to control the infection of A. hydrophila
Keyword: goramy, banana stem extract, Aeromonas hydrophila

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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