Judul: Health Status of Eel (Anguilla sp.) from Natural and Temporary Rearing.
Abstrak: Eel (Anguilla sp.) has been become a high economic valuable fisheries resources which has decreasing stock for the last two decade. The dependence of aquaculture from natural catching of juvenile, because of unknown breeding technique, derived this organism into over fishing for juvenile which is migrate to upstream or the adult which is migrate to deep sea to breed. Influence of pollution and or pathogen infection has been supported the decrease of stock in nature. The health status of this organism, therefore used to analysed population structure and the change of individual and population in order to make some strategy to keep this resources ever last and to develop the best aquaculture technique. The health status are information comprised organism condition linked with immunity of pathogen infection, interaction with other microorganism and influence of nature condition. This information would be useful to know the fitness of organism in their natural live or in artificial nature such as aquaculture. This research has been held to compare the eel health status from natural and temporary rearing during ten days of rearing in fish collector before use to aquaculture. This information would be useful to develop some standard health status of juvenile eel and to create the best temporary rearing method in order to keep the quality of juvenile. Sample were taken from two main rivers in Cilacap Residence (Donan River and Serayu River) where the eel use it as migration route. Sample also taken from bendung gerak Serayu, an artificial dam, which is obstructing the migration of eel. The result shows that although no significant different in condition factor, the temporary rearing has increasing reddish node in the head, body, fins and tail of eel. There are four parasite founded in this research that are Nematode (Procamallanus sp. and Anguillicola sp.) which are infected internal organ of eel and Platyhelminthes (Dactylogyrus sp. and Deropristis sp.) which are infected the gills. Identification of Anguillicola sp. is the first record from Indonesian waters. The bacteria founded in this research are Aeromonas hydrophylla, Pseudomonas luteola, Vibrio fluvialis, Aeromonas sobria and Aeromonas caviae. The highly prevalence of infection coming from genus Aeromonas and has been influenced the haematological condition and histopathology of eel. Decreasing of haematocrit level from 38.27 ± 0.63 in sample from bendung gerak Serayu to 37.54 ± 0.45 (%) and total erythrocyte from 2.47±0.18 to 2.36±0.11 (x106 cell/ml) after ten days temporary rearing in Kebasen shows that this group of bacteria has a very high potent causing anaemia in eel. In the other hand, increasing of total erythrocyte, decreasing of lymphocyte percentage and increasing of monocyte and neutrophil percentage for all observed sample indicated that eel had been developing innate immunity to face of inappropriate condition in temporary rearing. The pathogen disruption has also been detected from histopatologycal disorder such as hyperplasia of gills, necrosis and inflammation of heart and necrosis and lesion of muscle. Infestation of parasite with their hooks and or infiltration bacteria with their virulent factor could damage the cell of eel organ. This disruption shows that temporary rearing has been becoming
Keyword: eel (Anguilla sp.), health status, temporary rearing

Judul: Phylogeography of tropical eel (Anguilla spp) in Indonesia Waters
Abstrak: The freshwater eels (Anguilla spp: Anguillidae) are popular as a commercial important food, because of good nutritional value. These fish are also a well known for their unique catadromous life histories. These species breed far from offshore after migrate thousands kilometers from their growth habitats in freshwater and estuarine to their spawning area in oceanic waters. Most of the investigations concerning eels are concentrated on temperate species, in the north hemisphere mainly because of the economic importance of these species. Nowadays, the population of temperate eel, dramatically decrease is caused by habitat damage, illegal fishing and climatic changes in the ocean. As a consequence, tropical eels become important eel nowadays in the market, as well as the research on tropical eels become a new challenge. One of primary problems in tropical eels is that they have overlapping range of most morphological character, so species identification on this genus are no more sufficient. Then molecular approaches have been proposed for eel identification. This study has four main objectives: (1) to establish quick methods of identification of tropical eels; (2) to understand exact distribution and dispersal of tropical eel in Indonesia water; (3) to reveal the phylogenetic relationship among population in Indonesia and (4) to uncover population genetic structure of Anguilla bicolor between two Ocean. All of information obtained in this study revealed the conservation management of tropical eel in Indonesia water. The semi-multiplex method was proposed in this study has demonstrated the efficiency for in identifying seven species and sub-species of tropical eels with only one step PCR. By using this method, one could reduce the number of necessary sequences while the results are very sure for each species determination (we easily identified 1112 specimens). All of species were obtained in this study showed overlapping morphology and distribution. Especially for small specimens (mainly glass eels), the molecular method appears as indispensable. This method has proven to be most simple, quicker, lower cost (no acrilamide migration), specific/sensitive, and highly reliable way. The geographic distribution of tropical eels of the genus Anguilla in Indonesian waters was establish by identified genetically of all sample that obtain during this study. The genetically identification applied the semi-multiplex PCR method that recently developed in this study. We recognized four species and subspecies with wide distribution: A. b. bicolor, A. b. pacifica, A. marmorata and A. interioris, two species with limited distribution, close to endemism: A. celebesensis and A. borneensis and one subspecies A. nebulosa nebulosa that is only spread in river flowing into Indian Ocean. The phylogenetic relationship and genetic diversity was cosntructed and calculated based on mitochondria DNA cytochrome b gene sequence of Anguilla that covering all of the geograpical distribution in Indonesia waters. The genetic structure of populations that responsible for a given genetic architecture and evolutionary factors is an important objective of population genetics. In this study we present genetic diversity and phylogenetic relationship among and within species in genus Anguilla to understanding the evolutionary process of Anguillid that inhabit in Indonesia waters. Seven species of Indonesian tropical eel showed a higher haplotype and nucleotide diversity
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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