Judul: Efektivitas insektisida terhadap larva caplak sapi (Boophilus microplus) peternakan sapi potong di Jonggol Kabupaten Bogor
Abstrak: Boophilus microplus cattle tick is important ectoparasites of cattle, especially because of its hematophagous and also as vector of babesiosis and anaplasmosis. Application of chemical insecticide is still mostly done for control these tick. This study aimed to determine the efficacy of cypermethrin and propoxur as larvicides to B. microplus larvae. Field observation was also conducted to determine the prevalence, degree of ticks infestation, as well as the distribution of ticks infestations in cattle body region, i.e head and neck, abdomen, back, legs, and tail. Tick eggs from field collection were hatched to be larvae and tested in vitro to cypermethrin and propoxur in gradual concentrations 0.5 g/L, 1 g/L, 1.5 g/L, and 2 g/L. Testing conducted as much as three repetition on each group of 20 ticks larvae which were placed inside the insecticide impregnated paper. Observation of knockdown time (KT) were held for 6 hours then 24 hours for tick larvae mortality. Efficacy test showed 100% tick larvae were death at the 24th hour on all treatments. Based on these results, cypermethrin and propoxur stated effective to B. microplus larvae. Field observation showed the prevalence of B. microplus infestation in the amount of 46.88%, with the highest infestation obtained in the region of the head and neck (38.02%) and the lowest in the region of the tail (4.15%).
Keyword: Bogor Agricultural University (IPB), propoxur, efficacy of insecticides, cypermethrin, Boophilus microplus

Judul: Efikasi Insektisida Sipermetrin terhadap Larva Caplak Boophilus microplus dari Desa Pangumbahan Kecamatan Ciracap Kabupaten Sukabumi
Abstrak: Pangumbahan is a village located in a coastal areas that people there mostly works as fisherman. Other people activities undertaken are raising cattle. The cattle tick Boophilus microplus is considered the most importance cattle ectoparasite in tropics and subtropics region. B. microplus was also found on dog, goat and buffalo. Tick infestations in cattle causes direct impact such as skin irritation and loss of body weight and indirect impact such as vectors of diseases. This ectoparasite generally controled by using insecticide. Cypermethrin is synthetic pyretroids insecticide that mostly used to control household insect. The aim of this research was to determine the effication of Cypermethrin against cattle ticks larva of B. microplus. A number of 20 ticks larvae in gauze were dipped during 1 minute into 8 concentrations (0.125 gr/L; 0.25 gr/L; 0.5 gr/L; 1 gr/L; 1.5 gr/L; 2 gr/L; 2.5gr/L; and 3 gr/L). Control group done by the same method without any contact to the insecticide. The tick mortality observed at 1; 2; 3; 4; 5; 6; 12; 24; and 48 hours post exposure. The result showed that the effective concentration was 2 gr/L with average of mortality was 91.67% in 24 hours post exposure. The higher concentration of the insecticide caused the fastest death of the tick larvae
Keyword: Pangumbahan, efficacy, Cypermethrin, B microplus

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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