Judul: Mempelajari aspek fisiologi dan genetika resistensi antibiotik tetrasiklin pada baakteri fotosintetik anoksigenik MB-6
Abstrak: Bakteri fotosintetik anoksigenik MB-6 yang diisolasi dari kawasan air hitam Kalimantan Tengah memiliki resistensi alami terhadap tetrasiklin (5 µg/ml), kloramfenikol (100 µg/ml), trimetoprim (100 µg/ml), ampisilin (100 µg/ml), streptomisin (50 µg/ml), dan spektinomisin (50 µg/ml), yang menunjukkan bahwa fenomena resistensi terhadap antibiotik bukanlah suatu fenomena baru, tapi hal ini sudah berlangsung di alam secara sinambung. Sifat resistensi terhadap antibiotik tetrasiklin pada bakteri ini mampu mencapai 15 µg/ml. Penambahan tetrasiklin pada beberapa tingkat konsentrasi menyebabkan meningkatnya sintesis antena pemanen cahaya I dan II, hal tersebut mengindikasikan kemungkinan meningkatnya sintesis asam 8- aminolevulinat (ALA) intrasel. Tetapi hasil asai ALA menunjukkan dengan peningkatan konsentrasi tetrasiklin di media semakin menurunkan konsentrasi ALA ekstrasel. Hal ini kemungkinan ada hubungannya dengan mekanisme resistensi terhadap antibiotik tetrasiklin pada bakteri ini. Usaha kloning molekuler belum berhasil mendapatkan gen penyandi resistensi terhadap tetrasiklin dari isolat MB-6, tapi usaha kloning ini penting untuk memanipulasi bakteri ini selanjutnya.
Keyword: Aspek fisiologis, fotosintetik anoksigenik, bakteri

Judul: Isolasi Dan Penapisan Bakteri Fotosintetik Anoksigenik Untuk Penguraian Asam Asetat
Abstrak: Dalam penelitian ini tetah dilakukan kegiatan lsolasi yang menghasilkan 23 isolat bakteri fotosintetik anoksigenik (BFA). Semua isolat BFA dapat tumbuh baik pada pH 7.2 eli dalam media Sistrom dengan swnber karbon asam suksinat atau asam asetat. Tiga isolat diantaranya. yaitu Is-2al. 1s-2a3, dan Js--2bl memiliki tingkat pertumbuhan paling tepat pada hari ke-6 dibandingkan duapuluh isolat BFA lain yang ditumbuhkan pada kondisi media Sistrom tanpa nitrilotriacetic acid (NT A) dengan sumber karbon asam asetat ber-pH 7.2. Sebaliknya. isolat-isolat terpilih tersebut terlihat tidak menunjukkan adanya pertumbuhan, baik pada pH 5.0 maupun pH 5.5 dengan asam asetat atau asam suksinat sebagai sumber karbon, kecua1i Is-2bl. Pada media Sistrom dengan sumber karbon asam suksinat pH 5.5. Is-2bl menunjukkan kondisi pertumbuhan yang paling baik.
Keyword: 

Judul: The Construction of Greedy SVP LLL Algorithm
Abstrak: A lattice is a set of all integer linear combination of a set of linearly independent vectors in ℝ𝑛���. The independent vectors are called bases of lattice. Any lattice can be generated from many bases, and these bases have the same cardinality. In the lattice, the most fundamental and renowned problem is the Shortest Vector Problem (SVP). SVP is a tracking problem of the shortest nonzero vector in a lattice with equivalent bases. In two dimensions, SVP problem has resolved exactly by Gauss’ algorithm. When the lattice dimension is higher than two, A.K. Lenstra, H.W. Lenstra and L. Lovasz gave a LLL algorithm to compute approximation of nonzero shortest vector in the lattice. Reduced bases solution obtained from LLL algorithm still be an approximation and has polynomial running time of arbitrary dimension which large enough. In 1994, Schnoor and Euchner modified this LLL algorithm as a new variant which later was named deep insertion LLL algorithm. This algorithm is a modified version of the LLL algorithm to the terms of the exchange step to improve the accuracy of output of LLL reduced bases and applying it to the subset sum problem. The purpose of this research are: (1) Reconstruct the LLL algorithm and deep insertion LLL algorithm using a geometric approach. (2) Construct a greedy SVP LLL algorithm. (3) Implement the three algorithms in a symbolic programming language, and evaluate them experimentally. A bases ℬ=[𝐛���1,𝐛���2,…,𝐛���𝑛���] in ℝ𝑚��� is called reduced LLL with parameter 𝛿��� if satisfies: (a) |𝜇���𝑗���𝑖���|≤12, for every integer 𝑖���,𝑗��� with 1≤𝑖���<𝑗���<𝑛���. (b)𝛿���‖𝜋���𝑗���(𝐛���𝑗���)‖2≤‖𝜋���𝑗���(𝐛���𝑗���+1)‖2, for 𝑗���=1,2,…,𝑛���−1,where 𝛿��� is a reduced parameter of real numbers with 14<𝛿���<1. The first requirement is the reduced basis 𝛿��� must “nearly orthogonal” and in its computation case, this requirement can be reached out by using the Gram-Schmidt’s orthogonalization. While the second requirement is called exchange step, or used to called as Lovasz condition. By using both of these requirements, then they establish the LLL algorithm. Then, Schnoor and Euchner modify the LLL algorithm based on the requirements of the exchange step called the deep insertion LLL algorithm, where the exchange step is based on the comparison of the projected vector in orthogonal complement [𝐛���1,𝐛���2,…,𝐛���𝑘���−1]⊥ after j-th reduction. To construct greedy SVP LLL algorithm, the requirements of the exchange step is based on purely by comparing norm of lattice 𝐛���𝑗��� with norm lattice 𝐛���𝑖��� for 𝑖���=1,2,3…,𝑗���−1. The process of insertion reduced vector after the exchange step also has done greedily. Then, we calculate the number of arithmetic operation in greedy SVP LLL algorithm for further analysis. The result of our exprimentation for three algorithms on the certain matrix size shows that the running time of the three algorithms increases propotional to the size of the matrix. The result also shows that by using 𝛿���=34 for the LLL algorithm and the deep insertion LLL algorithm, and the greedy SVP LLL algorithm which is a new variant made by using no parameter of 𝛿���, outperform of the other of two previous algorithm in terms of speed with the same output.
Keyword: LLL algorithm, LLL deep insertion algorithm, greedy SVP LLL algorithm