Judul: Pengaruh sari temu hitam (Curcuma aeruginosa Rosb.) terhadap pertumbuhan beberapa bakteri enteropatogenik
Abstrak: Penelitian ini bertujuan untuk menguji sifat anti- mikroba dari sari temu hitam. Sari temu hitam diperoleh dari hasil penyaringan bertahap menggunakan kertas saring (Whatman nomor 40 dan 42) dan millipore (ukuran 0.45 µm dan 0.22 µm), dan sebagai bakteri penguji digu- nakan Escherichia coli, Salmonella typhimurium, dan Vibrio cholerae. Media kontak menggunakan kaldu nutrien (NB DIFCO) pada pH 5 atau pH 7. Inkubasi dilakukan pada suhu refrigerasi atau suhu kamar selama 0, 0.5, 5, 24, 29, 48, 53 dan 72 jam. Setelah inkubasi dilakukan pengu- kuran densitas optik bakteri dengan spektrofotometer pada panjang gelombang 623 nm. Dari hasil penelitian diketahui pada media pH 5 dan inkubasi suhu refrigerasi akan menyebabkan bakteri paling terhambat pertumbuhannya, dimana Escherichia coli dengan penambahan sari temu hitam sebesar 12.5%(V/V), Salmonella typhimurium dengan penambahan sari temu hitam sebesar 7.5% (v/v) dan Vibrio cholerae dengan penambahan sari temu hitam sebesar 7.5%(v/v) akan terhambat pertum- buhannya sebesar 100% setelah inkubasi selama 72 jam. ...
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Judul: Pencirian Struktur Kimia dan Aktivitas Antibakteri Fraksi Nonpolar Ekstrak Temu Hitam (Curcuma aeruginosa).
Abstrak: Temu hitam dikenal sebagai tanaman obat di Indonesia yang rimpangnya sering digunakan sebagai obat tradisional. Namun, hingga saat ini informasi mengenai komponen bioaktif yang terkandung dalam ekstrak rimpang tersebut masih sangat terbatas. Oleh karena itu, penelitian ini bertujuan mengisolasi metabolit sekunder dari fraksi nonpolar esktrak temu hitam dan uji aktivitas antibakterinya. Metabolit sekunder diisolasi dengan beberapa teknik kromatografi. Selanjutnya, ekstrak dan metabolit sekunder yang diperoleh diuji antibakterinya terhadap Bacillus cereus dan Salmonella typhi. Hasil penelitian menunjukkan ada 2 senyawa yang berhasil diisolasi dari ekstrak metanol temu hitam, tetapi hanya 1 senyawa yang berhasil diidentifikasi strukturnya. Struktur senyawa tersebut diidentifikasi berdasarkan data spektroskopi Nuclear Magnetic Resonance (1H dan 13C) dan dibandingkan dengan data sejenis yang telah dilaporkan. Struktur senyawa memiliki rumus molekul C15H22O2 dan ditetapkan sebagai kurkumenol. Hasil uji antibakteri menunjukkan bahwa senyawa tersebut merupakan salah satu senyawa dalam temu hitam yang berperan dalam aktivitas antibakteri.
Keyword: antibakteri, Bacillus cereus, Curcuma aeruginosa, kurkumenol, Salmonella thypi

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