Judul: Parasit pada Sayur Konsumsi di Sekitar Kampus IPB Dramaga Bogor.
Abstrak: Sayur merupakan makanan penting karena sangat manfaat untuk kesehatan dan metabolisme tubuh. Kebelakangan ini dengan kemajuan ilmu pengetahuan dan teknologi ditemukan ada peningkatan jumlah kasus food-borne disease karena mengonsumsi sayur mentah. Food-borne disease akibat penularan parasit intestinal atau protozoa merupakan suatu masalah kesehatan masyarakat yang umum pada negara berkembang. Tujuan penelitian ini dilakukan adalah untuk mengidentifikasi dan mengetahui prevalensi parasit yang mengontaminasi sayur yang umum dikonsumsi masyarakat di sekitar Dramaga, Bogor. Sebanyak 5 sampel sayur diantaranya bayam, kangkung, pakcoy, kol dan kemangi yang berasal dari pasar Cibeureum, Dramaga, Bogor. Metode penelitian ini dilakukan dengan metode sedimentasi (24 jam) dan sentrifugasi (2 jam) dipergunakan untuk mengetahui adanya parasit dalam sayur. Hasil penelitian menunjukkan semua sayur positif terkontaminasi parasit. Jenis parasit yang ditemukan adalah Tetrahymena spp., Rotifera spp., ektoparasit dan nematoda bebas. Prevalensi parasit paling tinggi dijumpai pada bayam dan prevalensi parasit paling rendah dijumpai pada pakcoy. Rata-rata jenis parasit yang paling banyak ditemukan pada tiap sayur adalah protozoa Tetrahymena spp. Tetrahymena spp. merupakan siliata bebas yang hidup di berbagai habitat termasuk air tercemar. Protozoa bebas dan nematoda bebas dapat berpotensi sebagai agen zoonotik dan karrier. Oleh karena itu. pencegahan dan penanganan yang baik penting untuk memastikan keamanan pangan dan mencegah food-borne disease.
Keyword: parasit, protozoa, sayur

Judul: Keanekaragaman dan Parasitisasi Parasitoid pada Pertanaman Sayuran di Bogor
Abstrak: In an agricultural area, agroecosystem could influence diversity and parasitism of parasitoids as natural enemies of insect pests. A survey to learn diversity and rate of parasitism of insect pests by parasitoids had been conducted in several agricultural fields with different criteria, such as farming practice (organic and convensional), species richness of vegetable crops (5-8 sp. and 9-15 sp.) and different crop ages (3, 4 and 5 months), in Bogor from August to October 2012. By making a 50 steps line transect for every field, eggs, larvae and pupa of insect pests were collected monthly, reared in laboratory and incidence of parasitism were calculated. The results showed that there were no significant differences on diversity and rate of parasitism based on three criterias used. However, based on the diversity of vegetable plant species around, the rate of parasitism in field with less plant species diversity (5-8 sp.) was higher than the field with more vegetable plant species diversity (9-15 sp.). These results might be caused by the limited number of samplings conducted and other potential factors such as surrounding habitat, seasonal fluctuation, and complex interactions between species in agroecosystem.
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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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