Judul: Non-Invasive Hormone Monitoring: Faecal Androgen and Glucocorticoid in Male Crested Macaques (Macaca nigra) in Relation to Seasonal and Social Factors.
Abstrak: Monitoring hormon secara non-invasiv menggunakan sampel feses merupakan teknik yang semakin populer. Hal ini didasarkan pada prinsip bahwa selain dari darah, hormon juga bisa diukur dari feses, urin dan saliva. Feses mengandung hormon steroid seperti progesteron, estrogen, androgen dan glukokortikoid dalam bentuk metabolit. Meskipun koleksi sampel feses relatif mudah, tetapi analisis hormon tidaklah mudah. Oleh karena itu, uji validasi untuk menentukan jenis metabolit hormon merupakan hal yang perlu dan penting untuk dilakukan, sehingga akan diperoleh hasil yang valid. Teknik non-invasiv ini memberikan kemudahan bagi kita untuk mempelajari fisiologi dari hewan liar atau hewan terancam punah (endangered) seperti monyet hitam Sulawesi (Macaca nigra) dari habitat alaminya. Monyet hitam Sulawesi adalah monyet endemik dari Sulawesi dengan status kritis (critically endangered animal). Namun, informasi tentang biologi reproduksi, fisiologi dan tingkah laku pada monyet ini masih sangat terbatas.
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Judul: Perilaku Harian Monyet Hitam Sulawesi (Macaca nigra) pada Masa Kebuntingan di Cagar Alam Tangkoko-Batuangus, Sulawesi Utara
Abstrak: Crested macaque (Macaca nigra), one of the seven endemic primates in Sulawesi is the most endangered macaque species that has been categorized as critically endangered by International Union for Conservation of Nature (IUCN). However, almost nothing is known about the reproductive biology in associated with the behavioral during pregnancy. The data is important to support a management and breeding programs such as pregnancy diagnostic and conservation program in this species. The research aimed to study the behavior of the crested macaques during pregnancy. Observations were performed on the 10 adult females of the Rambo 1 group (R1) which has been habituated at Tangkoko-Batuangus Nature Reserve, North Sulawesi. Behavioral data were collected using focal animal sampling and recorded using instantanaeous sampling on females during menstrual cycling, pregnancy, and after parturition (lactation). During five months observations, a total of 393,63 observation hours were recorded. The results showed that daily activities of the M. nigra during menstrual cycling were dominated by feeding (26.60%), foraging (15.95%), and locomotion (16.16%). Daily activities during pregnancy were dominated by feeding (27.03%), foraging (16.37%), and resting (13.45%), whereas after parturition (lactation) period was dominated by resting (26.12%), foraging (19.51%) and feeding (14.98%). The resting was the most activity in the end of pregnancy and few day after parturition. The diets which were collected successfully composed of the fruits (34 species, 20 families), arthropods (3 species, 2 families, 4 orders), fungi (4 genera and division), and plants (5 species and families). Climate influenced on the composition of the diet, especially on fruit and arthropods. In conclusion, the activity budgets were different during menstrual cycling, pregnancy, and lactation, especially feeding, foraging, locomotion, and resting.
Keyword: Bogor Agricultural University (IPB), diet, lactation, pregnancy, menstrual cycling, M. nigra

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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