Judul: Siklus Reproduksi Anak Tikus Dari Induk Yang Diberi Ekstrak Etanol Akar Purwoceng Selama 13–21 Hari Kebuntingan.
Abstrak: Purwoceng (Pimpinella alpina) is one of Indonesian medicinal herbals that was originating from high altitudes area such as Dieng at Central Java. Its root has an efficacious as aphrodisiac because of its compound such as isoflavon group. The aim of this study was to test the efficacy of phytoestrogens contained in purwoceng (Pimpinella alpina) on the descended testes, vaginal opening and estrous cycle. This study used two groups of pregnant rats. The first group consist of four pregnant rats which were given purwoceng root ethanol extract with dose of 25 mg / ml per 300 g BW orally at 13–21 gestation. The second group of rats were given water at the 13th day of gestation to 21 as a control. All pregnant rats were selected rats which has delivered 8–9 pups. The results showed that time of descended testes and vaginal opening of purwoceng group was earlier than control, descended testes of purwoceng group was on day 29 and vaginal opening was on day 36. Descended testes of control group was on day 34 and vaginal opening was on day 38. Length of estrous cycle in purwoceng group were longer than control with proestrus and estrus phase were also longer than control.
Keyword: Estrous cycle, ethanol extracted, purwoceng roots, Rattus norvegicus, vaginal opening

Judul: Study of Androgenic Effect of Ethanolic Extract of Root Purwoceng (Pimpinella alpina KDS) on the Reproduction Performance of Adult Female Rats (Rattus norvegicus)
Abstrak: which had been used in male reproductive research because it has androgenic property. Studies of purwoceng on female reproductive performance is not clearly yet. This research was conducted to explore the effect of purwoceng on duration of each period and total time of estrus cycle. A total of 48 female rats strain of Sprague Dawley were divided into 4 groups based on their estrous period: proestrus, estrus, metestrus and diestrus. Each group consisted of 6 rats as a control and 6 rats as treated animals. Extract of purwoceng was given oraly every day for 10 days. After 10 days, half of them were sacrificed and the rest of group were continued for vaginal smears examination until day 15. The results showed that purwoceng given at various periods during 2 cycles of estrous extend the time period of proestrus and estrus, and significantly different in estrous period when given during the period of estrus (P<0.05) compare to other period. Time period of metestrus and diestrus were decreased except period of metestrus which increased during administration of purwoceng on metestrus. The weight of uterine and ovarian was higher on rats receiving purwoceng during estrus period than the control (P<0.05). The conclusion of this research was that the administration of purwoceng was more effective when it was given at times of estrus period.
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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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