Judul: Karakteristik Struktur Anatomi Bagian Kayu Tarik dan Kayu Opposite pada Kayu Balik Angin (Alphitonia excelsa)
Abstrak: Wood is a very variable substance, with differences occurring among species and genera, within a species as well as within each individual tree because of a metabolism product. Wood variability becomes higher if the stem contains tension wood. The purpose of this study was to analyze anatomical structure, fiber quality and some physical properties of Alphitonia excelsa tension wood and compare them to those of the opposite one. Demarcation between juvenile and mature wood will also be assessed based on their fiber length, wood density, and microfibril angle. The results showed that there are differences in anatomical characteristics, physical properties, and the quality of the wood fibers between tension wood and opposite wood, except for fiber length, texture, color, grain, odour and taste, rays, perforation plate, and porosity. Average microfibril angle in tension wood was 23.81º, while in opposite wood was 26.23º in average. Moisture content, wood density, and specific gravity on tension wood region tended to be 6.5%, 11.63% and 13.16% higher than those of its opposite wood region.
Keyword: 

Judul: Struktur Anatomi dan Sifat Fisis Kayu Reaksi pada Kayu Terap (Artocarpus odoratissiumus) Asal Kalimantan Selatan
Abstrak: Wood is a product of tree metabolism. It varies among species, between trees of similar species and also within a single stem. Besides genetic factor, another factor that affecting these variabilities is growing condition and maturation level of the cells. Wood variation within a single stem of the tree will be increased dues to the existence of natural defect such as reaction wood, which can affect the entire characteristics and quality of the wood. Since study of reaction wood in tropical plantation wood species is very limited, this research aims to determine anatomical structure, fiber morphology and some physical properties of tension wood of terap (A. odoratissimus). The results are then compared to those of the opposite wood. The result shows that only MFA and wood density are varied between tension- and opposite woods. MFA of the tension wood are 14.83% greater than that of opposite wood, while wood density is 10.42% greater than that of the opposite wood. Compared to those of normal wood, fiber length of tension wood is shorther, but their MFA, specific gravity and wood density are bigger.
Keyword: fiber length, Artocarpus odoratissimus, tension wood, MFA, opposite wood

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
Keyword: