Judul: Social Behavior of Langur Borneo (Presbytis chrysomelas ssp. cruciger) in Lupak Mawang Resort, Danau Sentarum National Park
Abstrak: Status kritis dan terbatasnya penelitian pada populasi langur borneo mendorong dilakukannya pengumpulan data bioekologi, salah satunya mengenai perilaku sosial. Penelitian ini bertujuan untuk mengidentifikasi perilaku sosial; menganalisis hirarki dan peranan sosial pada kelompok; serta mengidentifikasi interaksi sosial langur borneo dengan jenis primata lain. Penelitian dilaksanakan pada bulan Juli hingga Agustus 2021 di Resort Lupak Mawang, Taman Nasional Danau Sentarum. Pengumpulan data primer perilaku sosial langur borneo dilakukan dengan metode scan sampling dan pencatatan continuous recording. Langur borneo melakukan 66 kali perilaku sosial dengan durasi total 72 menit. Pada perilaku agonistik, vokalisasi, bermain, menelisik, dan seksual, masing-masing persentase frekuensi 48,48%; 39,39%; 10,61%; 1,52%; dan 0%. Lama penggunaan waktu secara berturut-turut sebesar 44,44%; 41,67%; 12,50%; 1,39%; dan 0%. Dominasi teridentifikasi melalui perilaku agonistik, vokalisasi, dan peranan dalam mengatur pergerakan kelompok. Interaksi sosial langur borneo dengan jenis primata lain didominasi oleh perilaku agonistik dan besar disebabkan oleh tumpang tindih habitat., The critical status and limited research on the langur borneo population has prompted the collection of bioecological data on of which is social behavior. This study aims to identify social behavior; analyze the group’s hierarchy and social roles; and identify the social interactions between langur borneo and other primate species. This data research was carried out from July to August 2021 in Lupak Mawang Resort, Danau Sentarum National Park. Primary data of langur borneo’s social behavior was collected by using scan sampling method and continuous recording. Langur borneo performed 66 times social behaviors with a total duration of 72 minutes. Each frequency percentage of agonistic, vocalization, playing, grooming, and sexual behaviors are 48.48%; 39.39%; 10.61%; 1.52%; and 0%. Time length succesively are 44,44%; 41.67%; 12.50%; 1.39%; and 0%. The dominance was identified through agonistic behavior, vocalizations, and role in regulating group movement. The social interaction between langur borneo and other primate species is dominated by agonistic behavior and most influenced by overlapping habitat.
Keyword: langur borneo, social behavior, social hierarchy, social interactions

Judul: Social Behavior of Tricolour langur (Presbytis chrysomelas ssp. cruciger) at Majang Island Resort, Danau Sentarum National Park, Social Behavior of Langur Borneo (Presbytis chrysomelas ssp. cruciger) at Majang Island Resort, Danau Sentarum National Park
Abstrak: Langur borneo (Presbytis chrysomelas cruciger) merupakan jenis langur endemik kalimantan yang kini memiliki status keterancaman kritis, namun belum masuk ke dalam satwa dilindungi secara hukum di Indonesia. Hal ini disebabkan oleh minimnya acuan data mengenai bio-ekologi langur borneo, salah satunya perilaku sosial. Tujuan penelitian ini adalah mengidentifikasi perilaku sosial, menganalisis organisasi, dan interaksi langur borneo dengan jenis primata lain. Penelitian dilaksanakan pada Juli-Agustus 2021 di Resort Pulau Majang, Taman Nasional Danau Sentarum. Metode pengambilan data perilaku sosial dengan scan sampling dan pencatatan continuous recording. Hasil perilaku sosial yang didapatkan ialah vokalisasi (34,48%), menelisik (20,69%), agonistik (13,79&), seksual (3,45%), dan bermain (27,59%). Langur borneo hidup secara berkelompok dengan hirarki sosial yang dipimpin jantan dewasa. Tidak terlihat adanya interaksi langsung dengan jenis primata lain di Pulau Majang, selain tumpang tindih habitat akan ketersediaaan pakan.
Keyword: Danau Sentarum National Park, Langur Borneo, social behaviors, social organization.

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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