Judul: Pemberian ekstrak gambir (Uncaria gambir Roxb) sebagai antioksidan dalam air minum terhadap performa ayam petelur Isa Brown umur 40-43 minggu.
Abstrak: Gambir (Uncaria gambir Roxb) adalah salah satu tanaman herbal yang berpotensi sebagai sumber antioksidan alami. Penelitian ini bertujuan untuk mengevaluasi pengaruh pemberian ekstrak gambir terhadap performa ayam petelur. Penelitian ini menggunakan rancangan acak lengkap (RAL) dengan 3 perlakuan dan 5 ulangan. Peubah yang diamati adalah konsumsi pakan, konversi pakan (FCR), produksi telur massa, profil darah (eritrosit, hematocrit, haemogobin, leukosit dan diferensiasi leukosit), konsentrasi MDA didalam plasma darah serta nilai IOFC (Income Over Feed Cost). Materi penelitian yang digunakan yaitu 90 ekor ayam petelur strain Isa Brown umur 40 minggu. Perlakuan yang diberikan adalah R0 = ransum control, R1= R0 + 20 mg kg-1 BB (Bobot Badan) ekstrak gambir dalam air minum, R2=R0+ 40 mg kg-1 BB ekstrak gambir dalam air minum. Hasil menunjukkan bahwa pemberian 20 mgkg-1 BB gambir dalam air minum meningkatkan persentase eosinofil secara signifikan (P<0.05). Perlakuan tidak mempengaruhi performa dan profil darah. Pemberian gambir (Uncaria gambir Roxb) dalam air minum dapat menurunkan konsentrasi MDA dalam darah. Penggunaan 20 mgkg-1 BB gambir dalam air minum dapat menurunkan tingkat stress oksidatif pada ayam petelur. Kesimpulan penelitian ini adalah gambir dapat digunakan sebagai sumber antioksidan untuk ayam petelur.
Keyword: ayam petelur, gambir, performa

Judul: Suplementasi Ekstrak Gambir (Uncaria gambir Roxb) dalam Air Minum Sebagai Antioksidan terhadap Kualitas dan Kandungan MDA Telur Ayam Petelur Isa-Brown.
Abstrak: Gambier extract contains a polyphenols chemical compound that act as antioxidant. This study aimed to evaluate the effect of supplementation gambier extract on the quality and MDA (malondialdehyde) content of eggs. A completely randomized design was used in this experiment. The variables observed were egg quality (egg weight, albumin percentage, yolk percentage, yolk color, egg shell percentage, egg shell color, average shell thickness, egg shape index, albumin high, and Haugh Unit) and MDA content of yolk. This study used 90 of 38 weeks old of Isa Brown layer hen reared until 43 weeks old. The treatments were R0 = kontrol water, R1 = drinking water contained gambier extract 20 mg kg-1 BB), R2 = drinking water contained gambier extract 40 mg kg-1 BB. The results showed that supplementation of gambier extract decreased MDA content of yolk. Gambier extract supplementation significantly (P<0.05) increased eggshell color score, high of albumin, and Haugh Unit. The conclusion of the study was that gambier extract increased quality of egg and potential as antioxidant for the laying hen.
Keyword: egg quality, MDA, Uncaria gambier Roxb, yolk

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.
Keyword: