Judul: Sifat anatomi the least known wood species suku Magnoliaceae: Talauma gigantifolia Miq., T. liliifera O. K., T. rubra Miq., dan T. singapurensis Ridl.
Abstrak: INTRODUCTION: Indonesia has 4000 species of trees, but only 400 species of them have been known as commercial timbers. Magnoliaceae is a family which its member has not been much studied yet, except of Aromadendron elegans. Therefore, the objective of this study was to asses the wood properties of Talauma gigantifolia, T. liliifera, T. rubra and T. singapurensis, macroscopicand microscopically, and then compared them to the property of A. elegans’ wood. These four species of Talauma spp. were expected to be a better substitution of A. elegans which has been commonly used for construction and furniture manufacturing. In this study, the authentic wood samples collection of Xylarium Bogoriensis 1915 of Research and Development Center of Forest Engineering and Forest Products Processing, Bogor were used as the sample. Each species was represented by small portion of their heartwood. METHODS: Macroscopic characteristic namely wood color, figure, texture and grain orientation were observed following the method of Martawijaya et al. (1981) stated in Atlas Kayu Indonesia, while its microscopic namely vessel elements, axial and ray parenchyma as well as their fibers were observed by maceration and microtome specimens. Maceration was made following Forest Products Laboratory method, while microtome specimens were produced following Sass’ method (1961)
Keyword: 

Judul: Kajian Struktur Anatomi dan Sifat Fisis Kayu Balik Angin (Alphitonia excelsa): A Lesser Known Species from Kalimantan
Abstrak: Scarcity of wood supply for wood industries in Indonesian could be solved by searching several potential of wood species from natural forest. Among them, balik angin (Alphitonia excelsa) is one of the promising species since it belongs to faster grown lesser known wood species and abundant. To promote this species effectively, its anatomical structure and physical properties have to be studied. From the research it was showed that heartwood and sapwood are almost similar in colour (light gray), decorative (“V”-type), medium and even textured, straight grain, smooth, lustrous, medium hardness and odourless. Microscopic characteristics are 1, 4, 7, 9, 10, 13, 22, 30, 44, 47, 53, 56, 61, 65, 66, 69, 78, 79, 93, 97, 106, 109, 138, 153 and has resin material within the ray parenchyma cells. Average values of fiber length, moisture content, wood density, specific gravity, and MFA were 1042.84 μm, 13.03%, 0.49 g/cm3, 0.43 and 17.1˚, respectively. Fiber quality of this wood belonged to class of II-III with strength class of III.
Keyword: 

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