Judul: Addition of guava leaf extract to improve water quality and survival of tilapia (Oreochromis niloticus) in closed transportation
Abstrak: Kegiatan transportasi merupakan salah satu penyebab kematian ikan nila (Oreochoromis niloticus). Jauhnya jarak tempuh, penurunan kandungan oksigen terlarut, akumulasi karbon dioksida, tingginya kadar total amonia nitrogen, dan terganggunya parameter kualitas air dapat memicu stres pada ikan. Penambahan ekstrak daun jambu biji (Psidium guajava) diharapkan menjadi solusi alternatif. Penelitian bertujuan menganalisis pengaruh penambahan ekstrak daun jambu biji pada kegiatan transportasi tertutup dan pasca transportasi terhadap tingkat kelangsungan hidup, kualitas air, glukosa darah, dan pertumbuhan ikan. Penelitian menggunakan rancangan acak lengkap dua perlakuan dan satu kontrol dengan tiga ulangan. Dosis perlakuan mengacu pada hasil uji lethal concentration (LC50). Transportasi dilakukan 24 jam dan pemeliharaan setelah transportasi 21 hari. Hasil penelitian dosis 0,50% (JB2) memberikan nilai kualitas air yang lebih optimal dan perubahan kadar glukosa darah yang relatif lebih rendah dengan kontrol dan 0,25% (JB1). Selain itu, penambahan dosis 0,50% menghasilkan tingkat kelangsungan hidup 10% lebih besar dari kontrol dan setelah 21 hari pemeliharaan, penambahan dosis 0,25% dan 0,50% memberikan tingkat kelangsungan hidup 3% lebih tinggi dari kontrol. Kesimpulan penelitian ini, penambahan ekstrak daun jambu biji sebanyak 0,50% dari total volume air transportasi yang digunakan pada ikan nila memiliki pengaruh signifikan terhadap tingkat kelangsungan hidup, kualitas air selama transportasi, dan glukosa darah ikan setelah transportasi., Transportation activities are the causes of tilapia (Oreochoromis niloticus) mortality. Long distance traveled, decreased dissolved oxygen, carbon dioxide accumulation, high levels of ammonia nitrogen, and disruption of water quality parameters can trigger stress in fish. The addition of guava leaf extract (Psidium guajava) expected to be an alternative solution. Analyze the effect of the addition of guava leaf extract in closed and post-transportation activities on survival rate, water quality, blood glucose, and fish growth. The study used a completely randomized design with two treatments and one control with three replicates. The treatment dose refers to the results of the lethal concentration (LC50) test. Transportation was carried out 24 hours and maintenance after transportation was 21 days. The results of the study showed that the dose of 0.50% (JB2) provided more optimal water quality values and relatively lower changes in blood glucose levels with the control and 0.25% (JB1). In addition of a dose of 0.50% resulted in a survival rate 10% greater than the control and after 21 days of rearing, the addition of doses of 0.25% and 0.50% provided TKH 3% higher than the control. In conclusion, the addition of guava leaf extract as much as 0.50% of the total volume of transportation water used in tilapia has a significant effect on survival rate, water quality during transportation, and fish blood glucose after transportation.
Keyword: Kualitas air, Oreochromis niloticus, Transportasi

Judul: Penambahan Ekstrak Daun Jambu Biij (Psidium guajava) untuk Meningkatkan Kualitas Air dan Sintasan Benih Ikan Patin (Pangasionodon hyppophthalmus) pada Transportasi Ikan Sistem Tertutup
Abstrak: Stress adalah salah satu faktor utama yang menyebabkan kematian ikan selama masa transportasi. Pemberian ekstrak daun jambu biji diharapkan menjadi alternatif solusi masalah tersebut. Penelitian dilakukan dengan tujuan untuk menganalisis penambahan ekstrak daun jambu biji (Psidium guajava) ke dalam media air pada transportasi benih ikan patin (Pangasionodon hyppophthalmus) sistem tertutup terhadap kualitas air dan sintasan ikan. Penelitian menggunakan rancangan acak lengkap terdiri atas tiga perlakuan dan tiga ulangan. Perlakuan menggunakan ekstrak daun jambu biji dengan konsentrasi 0%, 0,5%, dan 1%. Transportasi dilakukan selama 24 jam. Hasil penelitian ini menunjukkan bahwa penambahan ekstrak daun jambu biji secara statistik tidak memberikan pengaruh nyata pada transportasi benih ikan patin, namun demikian pada konsentrasi 1% dapat mengurangi abnormalitas yang terdapat pada histologi insang dan memberikan keuntungan ekonomi yang lebih besar., Stress is one of the main factors causing fish mortality during transportation. Giving guava leaf extract is expected to be an alternative solution to this problem. The research was conducted with the aim of analyzing the addition of guava leaf extract (Psidium guajava) to water media in a closed system of juvenile patin fish (Pangasionodon hyppophthalmus) transportation on water quality and fish survival rate. The study used a completely randomized design consisting of three treatments and three replications. The treatments were using guava leaf extract with a concentration of 0%, 0.5%, and 1%. Transportation is carried out for 24 hours. The results of this study indicate that the addition of guava leaf extract statistically does not have a significant effect on the transportation of juvenile Asian catfish, however at a concentration of 1% it can reduce the abnormalities in gill histology and provide a greater economic benefits.
Keyword: gill histology, Pangasionodon hyppophthalmus, Psidium guajava, transportation, water quality

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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