Judul: Vocal Communication of Wild Crested Macaque (Macaca nigra).
Abstrak: Communication is an important aspect in the life of primates. In general, communication in primates involves the visual, auditory, and olfactory system. However, the vocal communication is an effective mode of communication since it may reach further than any other mode, especially for primates living in the forest habitat. Communication has important roles for the social life of primates such as individual or group identity, providing information of the presence of food and predators, and facilitating social interactions in primate social groups. This research was carried out on wild Macaca nigra, which is one of the seven macaque species endemic to Sulawesi. The species is characterised by a high level of social tolerance. Vocal communication studies on tolerant species are very limited compared to other, more despotic macaque species. The purpose of this study was to determine the variation of vocalizations of M. nigra and the social contexts in which the calls are issued. This study aims at providing a comprehensive overview of the complex social communication of these macaques and indirectly, contributes to the conservation and management of it, both in the wild and in captivity. A total of 1369 call units were generated from 328 sequences of calls. The calls were categorized based on their acoustic structure and the contexts in which they were uttered. Descriptive statistics of the acoustic parameter measurements are presented. This study found 11 call types emitted by M. nigra. Based on the physical structure of acoustics, the calls are categorized as tonal calls, non-tonal calls and complex calls (combination of tonal and non-tonal parts). M. nigra emitted the calls in all five main social contexts: affiliation, group cohesion (incl. group movement), agonism, predation and mating behaviour, whereas the loud call was uttered in several different contexts including non-social one. The calls were emitted by all individual, except the calls during mating behaviour and loud calls. Females and males had distinct call structure and calling time during mating behaviour. The loud call was issued only by adult males. One of the vocalizations can be considered as discrete signals while the others calls show high degrees of grading into each other. The discrete signals include calls in the group cohesion. The graded call signals were issued in the context of affiliation, agonism, the presence of predators and calls related to sexual behaviour. The ability of receiver to assess various clues and the usage of multimodal by the sender would influence the individual’s response to the graded signals. As a tolerant species, M. nigra showed high variation of calls compared to other monkey species. The call variation differences were likely influenced by various factors such as the character of species, behaviour and habitats. Vocal communication data on the species M. nigra can complement the data supporting the taxonomic determination and conservation activities of the species. The calls might give information regarding the emotional state of animals, which is important in ecotourism activities and captive animal management.
Keyword: Macaca nigra, vocalization, graded, social context, conservation, species management

Judul: Habitat characteristics and population size of black crested macaque (Macaca nigra Desmarest, 1822) in several habitat types in Tangkoko Nature Reserve, North Sulawesi
Abstrak: This study was conducted in Tangkoko Nature Reserve Bitung-North Sulawesi from July to August 2009. The objectives of this study were to identify habitat characteristics of Macaca nigra including physical component, vegetation structure, canopy cover, water availability, food availability, and to assess the population size in Tangkoko Nature Reserve. Vegetation analysis were made in five habitat types including beach forest, primary lowland forest, secondary lowland forest, transitional (ecotone) forest and burned forest. Fifty seven plant species from 29 families including seedling, sapling, pole, and tree were identified during this study. Population size was determined by direct encounter. Trees from family Anacardiaceae, Moraceae, Myrtaceae, Verbenaceae, and Clusiaceae were dominant in study area. The highest Diversity Index was found in lowland transitional forest. Similarity Index shown that every habitat types had little similarity, the biggest similarity index was found between primary forest and transitional (43.10 %). Canopy stratum C (4 - 20 m) was dominant in the study area. The most complex canopy strata were found in primary forest which had canopy stratum A, B, and C. Canopy cover density in the study area was relatively high with more than 85 % except in burned forest with a canopy cover density of 40.73 %. Macaca nigra more active in location with higher canopy cover density than in areas that have less canopy cover density. The cover was used by Macaca nigra for concealment, sleeping, eating, and resting. Five water resources were recorded in Tangkoko Nature Reserve during this study. Macaca nigra used these water resources as drink water sources, bathing places, reducing heat, and as playground areas. Nineteenth plant species were recorded eaten by Macaca nigra and fruit was their primary diet. During the study, nine groups of Macaca nigra were found. Four group (Rambo I, Rambo II, Rambo III, and Pantai Batu) intensively observed to know its population structure, sex ratio, and population size. Population size of these groups was 221 individuals. Based on the analysis with ArcView 3.3, the study site covering an area of 686.456 ha. Group size was 14 – 72 individuals/group. The group density was 0.58 groups/km2 and population density was 32.2 ind/km2. Ecotourism activities, hunting and habitat pressure (forest fire and Ilegal logging) are the main threats for Macaca nigra sustainability.
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Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition