Judul: The use of a combination of pine (Pinus merkusii) extract and powder in masculinization of red tilapia (Oreochromis sp.)
Abstrak: Ikan nila jantan memiliki pertumbuhan yang lebih cepat dibandingkan dengan ikan nila betina. Maskulinisasi pada ikan nila dilakukan untuk mempercepat masa produksi ikan dengan metode budidaya monoseks. Proses maskulinisasi dapat dilakukan dengan pemberian hormon androgen untuk menginduksi pengarahan kelamin jantan pada ikan. Penelitian ini bertujuan untuk mengetahui efektivitas penggunaan ekstrak dan serbuk buah pinus dengan metode perendaman dan suplementasi dalam pakan pada larva ikan nila berumur 5 hari selama 60 hari pemeliharaan. Terdapat empat perlakuan yaitu perendaman dengan ekstrak buah pinus dosis 0,2 ml.L-1 air selama 10 jam (I), perendaman dengan ekstrak buah pinus dan suplementasi serbuk buah pinus dalam pakan dosis 0,5 g/kg pakan (IS0,5), perendaman dengan ekstrak buah pinus dan suplementasi serbuk buah pinus dalam pakan pakan dosis 1g/kg pakan (IS 1,0) dibandingkan dengan perlakuan kontrol tanpa penggunaan ekstrak maupun serbuk buah pinus (K). Nilai nisbah kelamin jantan tertinggi yang dihasilkan yaitu pada perlakuan IS 1,0 sebesar 74,17±1,67%, dibandingkan dengan perlakuan IS 0,5 sebesar 66,67±7,20%, perlakuan I sebesar 61,67 ± 4,30% dan perlakuan kontrol sebesar 55,00±7,93 %. Berdasarkan penelitian ini, perlakuan terbaik terdapat pada perlakuan IS 1,0 dengan perbedaan sebesar 19.17% dibandingkan perlakuan kontrol. Sintasan ikan tertinggi yang didapatkan pada perlakuan IS 1,0 memiliki nilai sebesar 95,5±1,0 %, Male tilapia fish have faster growth compared to female tilapia. Masculinization in tilapia is performed to accelerate fish production using the monosex culture method. The masculinization process can be achieved by administering androgen hormones to induce male sex determination in the fish. This study aims to determine the effectiveness of using pine fruit extract and powder through immersion and supplementation methods in the diet of 5-day-old tilapia larvae for a 60-day rearing period. There are four treatments: immersion with pine fruit extract at a dosage of 0.2 ml/L of water for 10 hours (I), immersion with pine fruit extract and supplementation of pine fruit powder in the diet at a dosage of 0.5 g/kg of feed (IS 0.5), immersion with pine fruit extract and supplementation of pine fruit powder in the diet at a dosage of 1 g/kg of feed (IS 1.0), compared to the control treatment without the use of extract or pine fruit powder (K). The highest male sex ratio obtained was in the IS 1.0 treatment, which amounted to 74.17 ± 1.67%, compared to the IS 0.5 treatment at 66.67 ± 7.20%, the I treatment at 61.67 ± 4.30%, and the control treatment at 55.00 ± 7.93%. Based on this study, the best treatment was found in the IS 1.0 treatment with a difference of 19.17% compared to the control treatment. The highest fish survival rate obtained in the IS 1.0 treatment was 95.5 ± 1.0%.
Keyword: Nila, maskulinisasi, buah pinus, pertumbuhan

Judul: Masculinization of Tilapia (Oreochromis niloticus) Using Pine Pollen Extract Through A Soaking Method
Abstrak: Fitoandrogen berupa testosteron terkandung di dalam Pinus massoniana Lamb, P. tabulaeformis Carr, bahan ini dapat digunakan sebagai bahan maskulinisasi pada ikan. Penelitian ini bertujuan menguji efektivitas ekstrak serbuk sari pinus pada proses maskulinisasi ikan nila dengan metode perendaman larva serta pengaruhnya terhadap mortalitas ikan. Dosis ekstrak serbuk sari pinus yang digunakan dalam penelitian ini yaitu, 0,02 mL/L, 0,05 mL/L, 0,1 mL/L, dan 0 mL/L. Penelitian ini menggunakan materi uji larva ikan nila merah (Oreochromis niloticus) berumur 9 hari setelah menetas. Larva ikan nila diperoleh dari departemen budidaya FPIK IPB. Larva ikan nila dipelihara selama 60 hari pada akuarium 50 cm x 40 cm x 40 cm dan ketinggian air 30 cm dengan padat tebar 1,6 ekor/L (100 ekor/akuarium). Hasil penelitian menunjukkan bahwa penggunaan ekstrak serbuk sari pinus memberikan hasil positif dengan meningkatnya persentase kelamin jantan dengan hasil tertinggi yaitu 76,67±3,33%, Phytoandrogen in the form of testosterone are contained in Pinus massoniana Lamb, P. tabulaeformis Carr, this material can be used as masculinizing ingredient in fish. This research aimed to test the effectiveness of pine pollen extract on the masculinization process of tilapia with larval immersion method and its effect on fish mortality. The doses of pine pollen extract used in this study were 0,02 mL/L, 0,05 mL/L, 0,1 mL/L, and 0 mL/L. This study used test material of red tilapia larvae (Oreochromis niloticus) aged 9 days after hatching. Tilapia larvae were obtained from the culture department of FPIK IPB. Tilapia larvae were reared for 60 days in aquariums of 50 cm x 40 cm x 40 cm and a water level of 30 cm with a stocking density 1,6 fish/L (100 fish/aquarium). The results showed that the use of pine pollen extract gave positive results by increasing the percentage of male sex with the highest result of 76.67 ± 3.33%.
Keyword: Masculinization, male sex percentage, Pine pollen, Tilapia fish

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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