Judul: Tingkah Laku Sosial Bekantan (Nasalis larvatus) di Taman Safari Indonesia, Cisarua-Bogor
Abstrak: Proboscis Monkey (Nasalis larvatus) is a primate species that live in group, it occurred social interaction within group. In general, the form of social interaction among individuals include grooming activity, agonistic, play, and sexual. This research addressed to determine social behaviour of proboscis monkey. The objects of this study were six Nasalis larvatus with different ages and sexes. Social behaviour observation was carried out using focal animal method. Determination of the hierarchy in adult females based on grooming, agonistic, and sexual activities. The observation began at 09.00 a.m until 04.00 p.m for 492 hours. Adult females showed the greatest percentage on doing autogrooming and grooming to others than adult male and infants. Adult female with high rank showed less percentage (76,39%) on doing grooming than other adult females (78,00%). Male performed open mouth threat, showed canine, gave vocalization, and chasing the sounds. Females only performed open mouth threat and gave vocalization. Most adult female with high rank was done agonistic activity against other individuals (23,61%). Playing activities were done by the infants of proboscis monkey. Sexual behaviour only occurred between the adult male and female proboscis monkeys.
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Judul: Pemanfaatan Ruang oleh Bekantan (Nasalis larvatus Wunnb) pada Habitat Terisolasi di Kuala Samboja, Kalimantan Timur
Abstrak: Proboscis monkeys (Nasalis larvatus Wurmb) is an endemic primate species to the island of Borneo and has been classified as endangered species by IUCN. Fourty percent of this habitat has been lost and only 4.1% of this habitat occurs within designated conservation areas. Kuala Samboja River is an unprotected habitat of proboscis monkey. This area was narrow, isolated, and fragmented. The objectives of the research were to obtain habitat conditions, population, food source, and space use. Data were collected through vegetation analysis by line-plot sampling method, activity budget and use of space by instantaneous sampling method, whereas food sources by individual activity records of feeding (IARF) method. The groups were observed were Stan, Zacky, and Raja. The results of this study showed that the community of habitat are dominated by Sonneratia caseolaris, Cerbera manghas, Vitex pinnata, and Elaeocarpus stipularis. Twenty one of plant species were found as food sources, five of those were preferred i.e. S. caseolaris, V. pinnata, Deris sp., Hevea braziliensis, and Avicenia cf. officinalis. The population of proboscis monkey more than 143 monkeys, 98 monkeys divided to 9 groups (6 one-male groups, 3 all-male groups), whereas 45 monkeys unidentified. Generally, the monkeys spent more time for feeding in the morning and afternoon and resting in noonday. Feeding and moving activity of female greater than male but resting was lesser, whereas social activity was done by female only. Each mean daily range groups were 289 m (Stan), 260 m (Zacky), and 449 m (Raja), while home range size were 4.92, 4.52, and 6.92 ha, respectively. The groups of Stan, Zacky and Raja spent most of their time at heights of 9-12 m, 0-6 m, and 3-9 m, respectively. Use of canopy stratum influence by habitat conditions, temperature, blown of wind, and predators.
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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