Judul: Macro, micro and ultramicroscopic jati unggul nusantara and conventional teak wood.
Abstrak: Fast growing teaks become a solution to overcome teak supplies scarcity due to the long rotation in planting. However, many suspect that teak timbers from fast growing or shorter rotation trees have inferior wood properties than conventional long rotation teak. Jati Unggul Nusantara (JUN) as one of Indonesian fast growing teak is promoted more superior than other fast growing teaks. The tree will be harvested at 5 years age as veneer and furniture materials. Unfortunately, research regarding wood properties and appropriate utilization has not already conducted. It is important to find out its wood characteristics. The objectives of this research were to describe anatomical structure changes in faster growing teak compare to conventional one in the same age (4 and 5 years old), and study the suitability as veneer and furniture materials by conducted research on anatomical feature and other basic properties. The results showed that there are some differences in anatomical structure. JUN had fewer figures and more coarse texture that could decrease its properties as fancy veneer and furniture. The mean microfibril angle of JUN was 22,09°, which is narrower than that of conventional teak of the same age, which was about 25,29°. The crystallites degree increased (crystallites degree of JUN was 43,89% while conventional teak was 40,32%). Veneer recovery was 37% for 5 years JUN and 27% in 4 years JUN. Based on its characteristics, 5 years JUN is suitable for veneer and furniture materials but in medium quality. It is better if we wait for until these trees reach its maturation. Note that these research results just hold the characteristics of immature JUN and could not be generalized as whole properties of JUN, so it need more research regularly to observe the properties adjustment in the older tree to make an optimum age decision in harvesting.
Keyword: 

Judul: Evaluasi Kualitas Pertumbuhan dan Karakteristik Kayu Jati (Tectona grandis L. f.) Unggul Nusantara Umur 4 Tahun
Abstrak: INTRODUCTION. The lack of better quality of wood supply recently has resulted in the barrier of wood industry development in Indonesia. To overcome the above problem many community forests had been establishing by people using selected wood species. One of them is Jati (Tectona grandis) Unggul Nusantara (JUN) plantation belongs to Koperasi Perumahan Wanabakti Nusantara (KPWN) with teak as the main species. These stands were planted using tree spacing of 3 m by 3 m for the rotation of 5 years. To ensure these woods qualities were similar to those of the conventional teak, growth quality and wood properties have to be studied well. The aim of the study was to evaluate growth quality and wood characteristics of 4 year-old JUN by measuring the diameter and height of the trees and by studying wood physic properties and fiber morphology. MATERIALS AND METHOD. The main material used was increment core of 4 year-old of JUN extracted from the stem from the nine selected trees representing the diameter of the stands (small, medium and big) at dbh level using increment borer (ø 5 mm). From each sample tree, 2 pieces of increment core were extracted oppositely: one for wood physical measurement (moisture content at green condition/green MC, wood density and specific gravity/SG); and the other for fiber morphology measurement (fiber length and cell wall thickness). Both of them were measured radially (from pith to the bark). All measurements were carried out using procedural standard of Faculty of Forestry IPB. Demarcation between juvenile- and mature wood portions was evaluated using fiber length and wood density from pith to the bark. Effect of stem diameter and growth ring number was evaluated using t-student at the 95% confidence interval. Data processing was conducted with SPSS 13. RESULT AND DISCUSSIONS. It showed that growth quality of JUN was varied. Average value of diameter and height was 13.45 cm and 6.92 m, respectively. Growth rate of diameter and height was fast. They are around 3.36 cm and 1.73 m per year, respectively. It also showed that green MC, density, SG, fiber length and cell wall thickness of each group were varied. Average value of green MC was 112.27% (small tree), 127.53% (medium) and 146.35% (big); wood density was 0.99 g/cm3 (small), 1.02 g/cm3 (medium) and 1.09 g/cm3 (big); SG was 0.47 (small), 0.45 (medium) and 0.45 (big); fiber length was 741.15 μm (small), 845.52 μm (medium) and 833.30 μm (big), while wall thickness was 3.06 μm (small), 3.20 μm (medium) and 3.17 μm (big). Statistical analysis showed that green MC and wood density are influenced by diameter, while SG, fiber length and cell wall thickness are not. The bigger the diameter, the greater the green MC and the wood density. Based on its SG, the wood of JUN was classified into Strength Class of III. The result also showed that growth ring has no effect on the all parameters studied, except in case of SG on medium tree group and fiber length on small tree group. Generally, SG and fiber length tended to increase from pith to the bark.
Keyword: 

Judul: Mathematical Analysis of a Cholera Spread Infection Model  Using Vaccination
Abstrak: Kolera merupakan penyakit diare yang disebabkan infeksi pada usus oleh bakteri Vibrio cholerae. Bakteri tersebut masuk ke dalam tubuh seseorang melalui makanan dan minuman yang telah terkontaminasi yang akan mengeluarkan enterotoksin di dalam tubuh seseorang pada bagian saluran usus, sehingga menimbulkan diare disertai muntah yang akut dan sangat hebat, dan berakibat seseorang dalam waktu hanya beberapa hari akan kehilangan banyak cairan dalam tubuhnya sehingga mengalami dehidrasi. Penelitian ini bertujuan untuk menganalisis model untuk penyebaran infeksi kolera menggunakan vaksinasi. Terdapat dua titik tetap, yaitu titik tetap bebas penyakit dan titik tetap endemik. Pada simulasi numerik jika nilai reproduksi dasar yakni ℛ0 < 1 maka jumlah individu yang terinfeksi akan berkurang sehingga penyakit hilang. dst.., Cholera is a diarrheal disease caused by infection of the intestine by the bacterium Vibrio cholerae. These bacteria enter a person's body through contaminated food and drink, which will release enterotoxins in a person's body in the intestinal tract, causing diarrhea accompanied by acute and very severe vomiting, and resulting in a person just in a few days of losing a lot of fluids in the body so it becomes dehydrated. This study aims to analyze a model for the spread of cholera infection using vaccination. dst ..
Keyword: fungsi Lyapunov, infeksi kolera, vaksinasi