Judul: Efek Berbagai Jenis Pakan Kedelai (Glycine max L. Merrill) terhadap Produksi Hormon Estrogen pada Tikus Sprague Dawley Betina
Abstrak: Soybean (Glycine max L. Merrill) is a plant that contains high nutritional components. Researchs suggested that soybean contains high phytoestrogens, called isoflavones. This study aimed to measure the effect of soy feed contained isoflavones with three different concentration through the estrogen hormone level of Sprague Dawley female rats. There are 7 groups treatment (each group of 4 rats) which consists of a negative control group with feed casein (KN), 3 groups of feed with soybean powder 100% concentration (K1), 50% (K2), and 10% (K3) and 3 three other groups were given feed with soy protein isolate 100% concentration (IPK1), 50% (IPK2), and 10% (IPK3). The concentration of the hormone estrogen in the blood serum was measured by ELISA method (Enzyme-Linked Immunosorbent Assay). Results showed the source of isoflavones and the different protein levels were significantly different (p <0.05) the levels of the hormone estrogen of female mice with soybean powder treatment and not significantly different (p> 0.05) for soy protein isolate treatment. The concentration of the hormone estrogen increased as fed treatment soy 10% (K3), isolate 10% (IPK3), 50% (IPK2), and 100% (IPK1). Its concentration is 1455 ± 942.15 pg/mL, 939 ± 430.30 pg/mL, 869.44 ± 685.38 pg/mL, and 850 ± 46.39 pg/mL
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Judul: Efek Pakan Mengandung Isoflavon Kedelai terhadap Bobot Badan dan Kadar Androgen Serum Tikus Jantan
Abstrak: Isoflavone is a phytoestrogen. It can trigger both of estrogenic and antiestrogenic effects. Soybean was known as main source of isoflavone. It was suspected that soybean isovlavone had an antiestrogenic effect against body weight and androgen level of male rats. The objective of this research was to examine the influence of soybean isoflavone feeding against the body weight and androgen level of Sprague-Dawley male rats. Twenty eight rats were divided into seven groups which consist of one negative control group and six experimental groups (three groups were given soybean powder feedings (K1, K2, and K3) and three groups on soybean isolate feedings (I1, I2, and I3). The examined parameters were body weight, feeding consumption-efficiency, feces weight, and serum androgen levels (testosterone and dihydrotestosterone). The result showed that K2, K3, I1, I2, and I3 feeding increased body weight of male rats, whereas K1 feeding decreased them. The isoflavones used in this research has significantly reduced (p<0.05) androgen testosterone serum level. The highest reduction average percentage was on group K2 (95.11%), whiles the lowest percentage, on the other hand (16.24%) was observed on the group of I2 feeding. However, each soybean isoflavone-containing feed has insignificantly increased (p>0.05) androgen dihydrotestosterone. The highest average percentage of this increase was seen at the group of K2 feeding (325.44%), while the lowest one was on group of K1 feeding (175.05%).
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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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