Judul: Optimasi Salinitas untuk Kelangsungan Hidup dan Pertumbuhan Benih Ikan Tengadak Barbonymus schwanenfeldii
Abstrak: Environmental manipulation techniques are required to increase survival rate and growth of fishes, salinity manipulation is one of them. Salinity directly affects the living organisms life especially in survival rate and growth rate because it is strongly related with their osmoregulation process. The purpose of this research was to determine the optimum salinity for survival rate, growth, and economic profit for nursery activities of tinfoil barb (Barbonymus schwanenfeldii). This research consisted of four treatments of media salinity: 0 ppt (A), 2 ppt (B), 4 ppt (C), and 6 ppt (D). The rearing of tinfoil barb in different salinities showed significant effects on survival rate. Different salinity treatments also showed significant difference on specific growth rate of tinfoil barb.The optimum salinity for tinfoil barb was 4 ppt showed by the highest survival rate at 90%, highest specific growth rate at 1,65%, and highest profit achieved for nursery activities at Rp 139.002 with R/C ratio at 1,12.
Keyword: salinity., specific growth rate, survival rate, tinfoil barb

Judul: Efek Salinitas Berbeda terhadap Respon Fisiologis Benih Ikan Tengadak (Barbonymus schwanenfeldii Bleeker, 1854)
Abstrak: Ikan tengadak (Barbonymus schwanenfeldii) merupakan salah satu ikan air tawar asli Indonesia yang memiliki nilai ekonomis yang tinggi. Domestikasi ikan tengadak penting dilakukan untuk tetap menjaga kelestariannya. Dalam domestikasi ikan, salinitas merupakan salah satu parameter yang dapat meningkatkan pertumbuhan dan kelangsungan hidup ikan. Penelitian ini bertujuan menganalisis pengaruh salinitas terhadap kondisi fisiologis benih ikan tengadak (B. schwanenfeldii). Penelitian dilakukan dari bulan Juni hingga Oktober 2021 di Instalasi Riset Plasma Nutfah Perikanan Air Tawar, Kabupaten Bogor. Ikan tengadak diberi perlakuan salinitas 0, 3, 6, 9, dan 12 ppt dan dilakukan pengamatan selama 21 hari. Hasil penelitian menunjukkan bahwa peningkatan salinitas dari 0 ppt mengakibatkan meningkatnya parameter lingkungan (konduktivitas dan alkalinitas), meningkatkan kadar kortisol, dan menurunkan tingkat konsumsi pakan, sintasan, dan laju pertumbuhan benih ikan tengadak. Nilai kortisol dan glukosa paling tinggi pada perlakuan 6 dan 12 ppt. Kelangsungan hidup ikan tengadak paling tinggi terjadi pada perlakuan 0 dan 3 ppt. Benih ikan tengadak memiliki kisaran toleransi yang sempit terhadap salinitas (0-3 ppt). Benih ikan yang dipelihara pada salinitas di atas 3 ppt akan mengalami stres yang terlihat dari tingginya kadar kortisol dan glukosa darah., Tinfoil barb (Barbonymus schwanenfeldii) is one of the freshwater fish native to Indonesia that has high economic value. Domestication is an important method for the sustainable use of fish species. In fish domestication, salinity is one of the parameters that affect the growth and survival rate of fish. This study aims to analyze the effect of salinity on physiological conditions of tinfoil barb (B. schwanenfeldii) juveniles. The research was conducted from June to October 2021 at the Research Station for Freshwater Fisheries Germplasm, Cijeruk, Bogor. Tinfoil barb juveniles were treated with different salinities including 0, 3, 6, 9, and 12 ppt and observed for 21 days experiment. The research results showed that an increase in salinity from 0 ppt resulted in an increase in environmental parameters (conductivity and alkalinity), increased cortisol levels, and decreased feed consumption, survival rate, and growth rate of tinfoil barb. The highest cortisol and glucose levels occurred in the 12 ppt and 6 ppt treatments. The highest survival rate of tinfoil barb was observed in the treatment of 0 and 3 ppt. This research indicates that the juveniles of tinfoil barb show a narrow tolerant range on salinity (0-3 ppt). The fish fry reared at salinity above 3 ppt experienced stress conditions which can be detected by the high levels of cortisol and blood glucose.
Keyword: domestication, physiological, salinity, tinfoil barb

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology