Judul: Detection of Bovine-Viral-Diarrhea Antigen and  Antibody in bulk milk from Dairy Cattle in Cianjur Utara by Enzyme-Linked-Immunosorbent-Assay
Abstrak: Penyakit bovine viral diarrhea (BVD) adalah penyakit yang ditemukan pada ternak sapi di Indonesia dan sebagian besar kasus bersifat subklinis. Penyakit BVD termasuk kedalam penyakit hewan menular strategis (PHMS) di Indonesia, karena dapat menyebabkan penurunan produksi susu dan berdampak terhadap ekonomi. Surveilans terhadap penyakit infeksi, misalnya BVD, sangat penting dalam menyukseskan program pengendalian PHMS. Penelitian ini bertujuan mendeteksi keberadaan antibodi dan antigen virus BVD pada sampel susu kandang dari peternakan sapi perah di koperasi produksi susu (KPS) Cianjur Utara dengan metode enzyme linked immunosorbent assay (ELISA). Keberadaan antibodi pada 118 sampel susu dideteksi dengan metode indirect ELISA. Sampel susu yang dinyatakan positif dilanjutkan analisis deteksi antigen BVD dengan metode sandwich ELISA. Hasil penelitian menunjukkan bahwa sebanyak 80 sampel (67,80%) memiliki antibodi BVD, tetapi dari seluruh sampel susu yang positif ini tidak ada yang terdeteksi memiliki antigen BVD. Temuan ini mengindikasikan bahwa ternak sapi perah di KPS Cianjur Utara pernah terpapar virus BVD, tetapi saat ini ternak sapi tersebut tidak dalam fase terinfeksi atau infeksi yang terjadi merupakan infeksi akut pada masa lampau. Selain itu, hasil ini juga menunjukkan bahwa sampel susu kandang dapat menjadi pilihan sampel dalam uji screening untuk deteksi keberadaan antibodi dan antigen BVD pada sapi perah., Bovine viral diarrhea (BVD) is a disease that is still found in cattle in Indonesia, and most cases are not accompanied by clinical symptoms. Bovine viral diarrhea is classified as a strategic infectious animal disease (PHMS) in Indonesia, because this infection can cause decrease in milk production and have an impact on the economy. Surveillance of infectious diseases, such as BVD, is very important for PHMS control programs. This study aimed to detect the presence of antibodies and antigens BVD virus in bulk milk samples from dairy farms KPS Cianjur Utara with enzyme linked immunosorbent assay (ELISA) method. The presence of antibodies in 118 milk samples was detected by indirect ELISA method and the positive sample continued by antigen detection analysis with sandwich ELISA method. The results showed that 80 samples (67.80%) had BVD antibodies, but none of these were detected to have BVD antigens. It indicates that cattle in KPS Cianjur Utara have been exposed to BVD virus, but the cattle are not currently infected or the infection is an acute infection in the past. This study also showed that bulk milk can be a sample choice in the screening test for the detection of BVD antibodies and antigens in dairy cattle.
Keyword: antibodi, antigen, bovine viral diarrhea, Cianjur Utara, ELISA, Detection of Bovine-Viral-Diarrhea Antigen and  Antibody in bulk milk from Dairy Cattle in Cianjur Utara by Enzyme-Linked-Immunosorbent-Assay

Judul: Kajian serologis Bovine Viral Diarrhea (BVD) pada sapi potong impor di Daerah Banten
Abstrak: Bovine Viral Diarrhea (BVD) is an acute epizootic disease and often causes death which characterize by clinical symptoms such as diarrhea and erosive lesions in the gastrointestinal tract. The agent caused this BVD is a pestivirus, family Flaviviridae. This disease is a strategic infectious disease that should be concerned in Indonesia. The aim of this research was to asses this BVD’s diseases in imported cattle at Banten. Enzyme linked immunosorbant assay (ELISA) is one of the methods that can be used to detect of BVD virus infection. Samples which were used in BVD’s serological test in Banten were 230 samples. There were 173 (75.22%) samples showed positive results of BVD while about 57 (24.78%) samples showed negative of BVD.
Keyword: bovine viral diarrhea, cattle, ELISA

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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