Judul: Bioecology and bioactive compound detection of rotifera Brachionus spp. from coastal waterand estuary in North Sulawesi
Abstrak: One of the most important microorganism s is the plankton. The existence of plankton affect the water where they live because this organism has an important role as source of food for many marine organisms. Rotifers are microscopic aquatic animals of the phylum Rotifera. The research aims to find out the existence and the most dominant rotifers in coastal territorial waters and estuaries in North Sulawesi, and the relations hip between their abundance and some environmental parameters. To compare morphometry of wild rotifers Brachionus rotundiformis from different locations a nd the cultured rotifers fed with different microalgae within different salinities, analysing the life cycle and detecting bioactive compound. The research was done in coastal ar eas and estuaries of North Sulawesi. Plankton sampling was done in several br ackishwater ponds and coastal areas along Manembo-nembo, Minanga, Wori , and Tumpaan. Samplings were conducted during east and west seas ons, as well as high and low tides. Temperature, salinity, pH, turbidity, and dissolved oxygen were measured in situ using test kit water. Samples of rotifer s were collected by deploying a pankton net horizontally along 10 m, and were pres erved using formaldehyde solution for further identification and measurements. Th e rotifers were cultured with different salinity (4, 20, 40, 50, 60 ppt) and fe d with different micro algae ( Nannochloropsis oculata and Prochloron species). The measurement for morphology characteristic were conducted on lorica length, lorica width and anterior width.
Keyword: brachionus rotundiformis, bioactive compound, in situ, different salinity, different micro algae

Judul: Pertumbuhan Populasi Rotifera (Brachionus sp.) dengan Pemberian Pakan Alami Mikroalgae Monospesies dan Multispesies.
Abstrak: Penelitian ini bertujuan untuk mengetahui kelimpahan dan pertumbuhan optimum Brachionus sp. sehubungan dengan pemberian pakan alami mikroalgae (Nannochcloropsis sp., Dunatella sp., Isochrysis sp" dan Pavlova sp.) secara monospesies dan multispesies. Penelitian ini dilaksanakan di Laboratorium Kultur Plankton, Jurusan Manajemen Sumberdaya Perairan, Fakultas Perikanan dan IImu Kelautan Institut Pertanian Bogor. Waktu pelaksanaan penelitian pada bulan Juli-Agustus 2002, meliputi penelitian pendahuluan dan penelitian utama.
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf