Judul: Population Distribution and Exploration Area of Javan Langur (Trachypithecus auratus) at Cimande Resort, Gunung Gede Pangrango National Park
Abstrak: Lutung jawa (Trachypithecus auratus) merupakan salah satu primata endemik Pulau Jawa yang dilindungi. Sedikitnya data mengenai lutung jawa menjadikan penelitian ini penting untuk dilakukan. Penelitian ini bertujuan mengidentifikasi sebaran populasi dan mengukur wilayah jelajah lutung jawa di Resor Cimande, Taman Nasional Gunung Gede Pangrango serta mengetahui faktor yang memengaruhi pergerakannya. Pengumpulan data dilakukan dengan metode eksplorasi serta penandaan pada Global Positioning System (GPS) dan Avenza Maps lalu diolah dan dipetakan dengan ArcMap 10.8. Populasi lutung jawa di Resort Cimande ditemui 10 kelompok pada 4 blok hutan yang berbeda dengan estimasi total populasi sebanyak 52 individu, jumlah individu per kelompok terdiri dari 1-9 individu, kepadatan populasi lutung jawa 0,33 ind/ha, nisbah kelamin adalah 1:2, dan persentase struktur umur menurun (piramida terbalik). Wilayah jelajah lutung jawa di Resort Cimande berkisar 2,45 - 21,75 ha. Faktor biotik yang memengaruhi pergerakan lutung adalah ketersediaan pohon pakan, keberadaan manusia dan satwa lain terutama primata. Faktor abiotik yang paling memengaruhi pergerakan lutung adalah curah hujan., Javan langur (Trachypithecus auratus) is one of the endemic primates of Java Island that is protected. The lack of data about Javan langurs makes this research important. This research aims to identify the population distribution and measure the home range of the Javan Langur in Cimande Resort, Gunung Gede Pangrango National Park and to determine the factors that influence its movement. Data collection was carried out using the exploration method and marking on the Global Positioning System (GPS) and Avenza Maps, then processed and mapped with ArcMap 10.8. The Javan langur population in Cimande Resort was found in 10 groups in 4 different forest blocks with an estimated total population of 52 individuals, the number of individuals per group consisted of 1-9 individuals, the population density of Javan langurs was 0.33 ind/ha, the sex ratio was 1:2, and the percentage of age structure was decreasing (inverted pyramid). The home range of the Javan Langur in Cimande Resort ranged from 2.45 - 21.75 ha. Biotic factors that influence langur movement were the availability of food trees, the presence of humans and other animals, especially primates. The abiotic factor that most influences langur movement was rainfall.
Keyword: home range, javan langur, population distribution

Judul: Mapping the Habitat Suitability of the Javan Langur (Trachypithecus auratus Geoffroy, 1812) in the Mount Gede Pangrango National Park
Abstrak: Lutung jawa (Trachypithecus auratus) merupakan satwa endemik Indonesia yang dapat ditemukan di Taman Nasional Gunung Gede Pangrango (TNGGP) dan saat ini memiliki status konservasi rentan. Salah satu upaya konservasi untuk menjaga populasi satwa ini yaitu dengan studi kesesuaian habitat. Penelitian ini bertujuan untuk mengetahui komponen yang mempengaruhi sebaran lutung jawa dan kesesuaian habitatnya di TNGGP. Analisis yang digunakan pada variabel lingkungan yaitu analisis multikolinearitas dan pembangunan model kesesuaian habitat diolah dengan Maximum Entropy. Hasil menunjukkan bahwa komponen habitat dengan peluang kehadiran lutung jawa paling tinggi berada pada habitat yang dekat dengan primata lain dan lokasi wisata, berada pada hutan dengan kerapatan hutan tinggi, ketinggian kanopi 26 m, ketinggian tempat 700 mdpl, kelerengan agak curam (17%), memiliki jarak 110 m dari sungai, 4500 m dari perkebunan, 150 m dari semak belukar, serta 500 m dari pemukiman atau lahan terbangun. Hasil pemodelan di TNGGP menunjukkan terdapat kawasan seluas 589,54 ha sangat sesuai, 1.080,35 ha sesuai, 2.533,31 ha cukup sesuai dan 20.075,64 ha kurang sesuai., Javan langur (Trachypithecus auratus) is an endemic species in Indonesia that can be found in the Mount Gede Pangrango National Park (TNGGP) and currently classified as vulnerable. The way to maintain this species population is identify the suitability of its habitat. This research aims to identify the factors that affect distribution of javan langur and their habitat suitability in TNGGP. Environmetal variable was analyzed using multicollinearity analysis and habitat suitability model build using Maximum Entropy. The results show that the habitat components with the highest probability of javan langur presence are habitats that close to other primates and tourist sites, and near from forests with high forest density, an forest canopy height of 26 m, an elevation of 700 masl, moderate steep slope (17%), a distance of 110 m from rivers, 4.500 m from plantations, 150 m from shrubland, and 500 m from settlements and built-up land. The modeling results indicate there are areas of 589,54 ha that are highly suitable, 1.080,35 ha that are suitable, 2.533,31 ha that are moderately suitable, and 20.075,64 ha that are less suitable in TNGGP.
Keyword: habitat, habitat suitability, javan langur, modeling

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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