Judul: Keanekaragaman Selaginella di Jawa Barat.
Abstrak: Selaginella is a genus of ferns in the family Selaginellaceae. It is characterized by having small leaves and the spongarium on the tip of each branch. The society of West Java have been a long time used Selaginella as vegetable and dill, but the taxonomic information of Selaginella in West Java is still poorly known. The aim of this research was to describe the diversity of Selaginella in West Java. This research used 316 herbarium specimens of Selaginella collected by Plant Taxonomy Laboratory, Department Biology of Bogor Agricultural University and Herbarium Bogoriense Botanical, Research and Development Cibinong. From each specimen was observed the mophological characters, recorded the spread site, identified, then arranged the identification key. This study showed that 18 species found in West Java, namely S. aristata, S. biformis, S. ciliaris, S. frondosa, S. intermedia, S. involvens, S. mayeri, S. opaca, S. ornata, S. plana, S. remotifolia, S. rothertii, S. subalpina, S. subspinulosa, S. uncinata, S. willdenovii, S. zollingerian and Selaginella sp 1. Selaginella is able to live at altitudes ranging from 20 m above sea level (asl) to > 2500 m asl, with a variety of habitats including primary forest, in the rice fields, near the waterways, and in the open area. An identification key of Selaginella in West Java was provided in this paper.
Keyword: identification key, Selaginella, taxonomic, West Java.

Judul: Keanekaragaman Selaginella di Jawa Tengah
Abstrak: Selaginella is a single genus belong to family Selaginelaceae which include approximately 750 species spread all over the world. The diversity of Selaginella can be found in lowland to mountain rainforest. This study aimed to describe the diversity of morphological characters and the distribution of Selaginella in Central Java, then to provide descriptions and identification key of Selaginella species in Central Java. The method used to assess the diversity Selaginella in Central Java included observation and identification of morphological characters. In Central Java, there were found 10 species of Selaginella, namely S. plana, S. remotifolia, S. involvens, S. ornata, S. ciliaris, S. opaca, S. modica, S. aristata, S. subalpina, and Selaginella sp. Selaginella varied on some morphological characteristics such as branching pattern, rhizofor, lateral leaves, median leaves, axillary leaves, and Strobilus shape. The distribution of Selaginella is fairly even in Central Java ranging from the altitude of 200 to 2771 m asl. Selaginella species found in the lowest altitude was Selaginella sp. (200 m asl), while at the highest altitude was S. plana (2771 m asl).
Keyword: Selaginella, Selaginellaceae, Taxonomy, Central Java.

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model