Judul: Kajian Kualitatif Residu Melengesterol Asetat (MGA) pada Daging Sapi Beku Impor dengan Metode ELISA
Abstrak: Melengesterol Acetate (MGA) is a synthetic anabolic steroid hormone used as growth promoter and suppress estrus in some feedlot exporter. Most of the synthetic anabolic steroids have a poor metabolism so it can be stored in an unchanging state in the liver, kidney, muscle, and fat of animals. MGA residues in beef can lead the risk of health problems in humans if it is high accumulates in the body such as toxicity, hypersensitivity, carcinogenic to teratogenic disorders, therefore the presence of MGA residues in beef have become the government and the world concern in the safety of foods from animal origin. Enzyme Linked Immunosorbant Assay (ELISA) is a serological method that can detect the presence and concentration of MGA residues in beef. Results obtained by using the ELISA method in this study shows that 83,72 % samples have concentration of MGA residues in imported beef is below the maximum residue limits established by Standar Nasional Indonesia (SNI 2000)
Keyword: residue., Melengesterol Acetate (MGA), ELISA, Imported Beef

Judul: Kajian Kualitatif Residu Trenbolon Asetat pada Daging Sapi Beku Impor dengan Metode ELISA
Abstrak: Hormone residues in meat are chemical hazard that can induce reproductive disorders if accumulated in human’s body. One of hormone residue that can be found in meat is trenbolone acetate. Trenbolone acetate is a steroid hormone synthesized from testosterone and commonly used as growth promoter in livestock animals. Inside the body, it will be metabolized in to trenbolone acetate and 17β-trenbolone that deposited in muscles. The presence of residues become a food safety’s issue that needs to be concerned. Therefore, residues check in imported meat must be done as one of customer’s protection effort. Enzyme linked immunosorbant assay (ELISA) is a method that can be used to detect hormone residue’s concentration in food product. Residue’s standard of 17β-trenbolon has range of concentration starts from 0 25, 50, 100, 200, and 400 ppt. The result of ELISA in 64 samples shows that imported frozen meat which have been tested are safe from 17β-trenbolone’s residues which was stated by Codex Alimentarius Commission
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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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