Judul: Peran ekstrak tempe terhadap kadar DNA dan RNA testis tikus usia lepas sapih
Abstrak: Tempeh is one of soy-based foods containing phytoestrogen which has similar benefit with estrogen. The phytoestrogen in soybean derived from isoflavone group. The objective of this research was to understand the effect of feeding tempeh extract on testes’ DNA and RNA level also testosterone concentration of weaning age rat until before puberty. Eighteen male rats were divided into two groups, which were control group that did not receive any treatment, and group that received 0.5 g/mL/day tempeh-extract-feeding treatment. At the age of 28, 42 and 56 days, testes and blood of male rats were collected. Parameters observed in this research were wet and dry weight testes, DNA and RNA levels, also testosterone concentration. Data obtained were analysed using Independent Samples T-test method with 95% confidence interval. Results showed that there was a significant decreasing (P<0.05) wet and dry weight testes, also total DNA and RNA level on age 28 days, but there were a significant increasing (P<0.05) on age 28 days. Testosteron concentration tended to decrease on 28 and 42 days old but it tended to increase on 56 days old.
Keyword: total of DNA and RNA, testosterone, testes, tempeh, phytoestrogen, Bogor Agricultural University (IPB)

Judul: Peran Ekstrak Etanol Tempe Terhadap Kadar DNA dan RNA Testis Tikus Jantan Usia 70 hari
Abstrak: Phytoestrogen is a subtance in soybean that have similiar structure with natural estrogen. Soybean is the main raw material of making tempe. Phytoestrogen are natural estrogen in isoflavon group. This study was conducted to investigate the role of tempe extract in reproduction performance of adult male rats. Nine male rats weaning age (21 days) were divided into 3 groups, control, treatment groups that were given a tempe extract 0.25 g/rat/day and 0.5 g/rat/day until ages of 48 days. Testicular wet weight, testicular dry weight, concentration of DNA levels, concentration of RNA levels, and sperms quantity in each group were measured. Data were collected at the age of 70 days and were analyzed using ANOVA test and Duncan test with 95% confidence interval (a=0.05).The results show that tempe extract of 0.25 g/rat/day could decrease the concentration of DNA levels and 0.5 g/rat/day increase the RNA levels and the sperm quantity.
Keyword: Bogor Agricultural University, tempe extract, male rats, rna, dna

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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