Judul: Toxicity of heavy metal’s lead (Pb) and its effects on oxygen consumption and hematological response of juvenile tiger grouper (Epinephelus fuscoguttatus)
Abstrak: Lead (Pb) is a toxic and dangerous heavy metal, most found as contaminants and tend to interfere the survival of aquatic organisms. The aim of this research was to analyze the effect of lead toxicity at various concentrations to the level of oxygen consumption, blood glucose level, hematological response (hematocrit, hemoglobin, number of erythrocyte and leukocytes), survival and growth of tiger grouper fish. This study was conducted in the two stages, those are: acute and sub–chronic test. The results showed that the impact of lead toxicity in juvenile tiger grouper fish would reduce the level of oxygen consumption, hematocrit, hemoglobin and the number of erythrocyte, those were equal to 0.34 mg O2/gr of body weight / hour; 9.66%; 2.64 % and 0,77x106 cells/mm3. Besides the effect of lead toxicity also increases the number of leukocytes (0,81x106 cells/mm3), blood glucose levels (90.79 mmol / liter), effect growth rate and reduce the survival rates.
Keyword: 

Judul: Supplementation of humic acid in the diet of tilapia Oreochromis niloticus cultured at water contaminated with lead (Pb)
Abstrak: Cemaran logam berat seperti Pb banyak ditemukan di beberapa perairan, baik danau maupun sungai, di Indonesia.Oleh karena itu, penelitian ini bertujuan mengevaluasi pengaruh penambahan asam humat dalam pakan terhadap kinerja pertumbuhan, histologi, dan kualitas daging ikan nila yang dipelihara pada air tercemar Pb. Terdapat empat perlakuan, yaitu penambahan asam humat ke dalam pakan sebanyak 0,0, 0,8, 1,6, dan 2,4 g/kg. Pakan-pakan tersebut diberikan ke ikan nila yang dipelihara di dalam air yang mengandung Pb 0,023-0,037 mg/L. Ikan nila berukuran 17,36±0,01 g sebanyak 15 ekor dipelihara pada akuarium berukuran 90x45x45 cm selama 55 hari. Ikan diberi pakan tiga kali sehari secara at satiation. Pergantian air dilakukan setiap hari sebanyak 95%. Perlakuan penambahan asam humat memiliki nilai laju pertumbuhan spesifik, jumlah kebutuhan pakan, rasio konversi pakan, rasio efisiensi protein, serta bobot akhir yang lebih baik dibanding tanpa penambahan asam humat. Humat 1,6 g/kg memiliki nilai biomassa yang berbeda nyata hingga 28,5% lebih tinggi dibandingkan Humat 0,0 g/kg. Terjadi kerusakan jaringan insang, hati, dan ginjal di seluruh perlakuan dengan tingkat kerusakan hati dan ginjal terparah pada perlakuan humat 0,0 g/kg. Humat 1,6 g/kg merupakan dosis optimal untuk ikan nila. Tidak ditemukan akumulasi Pb di daging ikan nila. Kata kunci: Asam humat, Oreochromis niloticus, Timbal (Pb), Heavy metal contamination such as Pb is found in several waters, both lakes and rivers, in Indonesia. Therefore, this study aimed to evaluate the effect of the addition of humic acid in the feed on the growth performance, histology, and meat quality of tilapia reared in Pb polluted water. There were four treatments, namely the addition of humic acid to the feed either of 0.0, 0.8, 1.6, and 2.4 g/kg. The feeds were given to tilapia reared in water containing Pb 0.023-0.037 mg/L. Fifteen tilapia measuring 17.36±0.01 g were kept in an aquarium measuring 90x45x45 cm for 55 days. Fish were fed three times a day at satiation. Water changes were carried out every day as much as 95%. The addition of humic acid had a better specific growth rate, total feed requirement, feed conversion ratio, protein efficiency ratio, and final weight than without the addition of humic acid. Humic 1.6 g/kg has a significantly different biomass value up to 28.5% higher than Humic 0.0 g/kg. There was damage to gill, liver, and kidney tissue in all treatments with the worst level of liver and kidney damage in the humic treatment of 0.0 g/kg. Humic 1.6 g/kg is the optimal dose for tilapia. No accumulation of Pb was found in tilapia meat. Keywords: Humic acid, Oreochromis niloticus, Lead (Pb)
Keyword: Humic acid, Oreochromis niloticus, Lead (Pb)

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
Keyword: