Judul: Prevalensi Kasus Kriptosporidiosis pada Sapi Potong di Kecamatan Cipatujah dan Cikalong, Tasikmalaya, Jawa Barat
Abstrak: Cryptosporidiosis is caused by Cryptosporidium sp. often occurs in cattle. This research aimed to determine the prevalence of Cryptosporidium sp infection in cattle at Cipatujah and Cikalong regency, Tasikmalaya, West Java. The research started in October 2012 to June 2013 used fecal specimens from 203 cattles of 117 farmers. Based on gender, sample consisted of 168 cows and 35 bulls. Based on age, consisted of 151 adult cattles, 24 heifers and 28 calves. Sample of feces were examined by floating sheather sugar, then afterwards observed using a light microscope. Percentage prevalence of Cryptosporidium sp at Cipatujah regency (13.08%) was higher than at Cikalong regency (8.33%). The infection of Cryptosporidium sp was higher in calves and heifers than adult cattles. The result of statistical tests shows the prevalence of cryptosporidiosis infection based on gender at Cipatujah regency is significant difference (P<0.05), but based on age at Cipatujah and Cikalong regency are no significant difference (P>0.05).
Keyword: prevalence, gender, Cryptosporidium sp, cattle, age

Judul: Kajian Kasus Kriptosporidiosis pada Sapi Potong di Kecamatan Ujung Jaya, Sumedang, Jawa Barat
Abstrak: Cryptosporidiosis is a zoonoses caused by Cryptosporidiumspecies. This research were aim to study and identification the prevalence of C. parvum in cattle on Ujung Jaya Regency, Sumedang, West Java. This research studied 60 fecal specimens, consisted of 10 calves, 9 heifers, and 41 adult cattles. And based on gender, consisted of 46 cows and 14 bulls. Samples were examined by floating sheater sugar and microscopic examination. The prevalence of Cryptosporidiosis on Ujung Jaya Regency was 11.67%. Based on statictical analysis, age and gender could not increase the prevalence of Cryptosporidiosis significantly (P>0.05). And based on the descriptive analysis the prevalence of Cryptosporidiosis in bulls (14.29%) higher than in cows (10.87%), and for adult cows (7.32%) is lower than neonate calf (20%) and calf (22.22%).
Keyword: Bogor Agricultural University, Cryptosporidiosis, prevalence, cattle, Ujung Jaya  Sumedang

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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