Judul: Pemakaian hasil fermentasi daun mata lele Azolla sp. sebagai bahan baku pakan ikan nila Oreochromis sp.
Abstrak: The good nutritional content of Azolla sp. shows that this leaves has the potential to be utilized as an alternative feed ingredient for fish. The objective of this experiment was to find an alternative high quality herbal ingredient for tilapia feed and to assess the most optimal dosage of azolla leaves fermented with Trichoderma harzianum in tilapia feed. The experiment consisted of two stages, the first stage was aimed at finding the best fermentation period that result in the best nutritional quality of azolla leaves, whereas the second stage of experiment was performed to evaluate the best inclusion level of fermented azolla leaves in tilapia feed by assessing growth performance. Tilapia with an average body weight of 10,59 ± 1,29 g was used as the experimental animal. Experimental diets were obtained by repelleting commercial feed with different level of fermented azolla leaves, namely treatment 0 % (A/control), 30 % (B), 60 % (C), and 90 % (D). Fish was cultured for 40 days during which the growth of the fish was observed, and feces was collected for 15 days for digestibility test. The results showed that two days fermentation period resulted in the best improvement of azolla leaves nutritional content with reduction in fiber content of 37,19 % and protein content enhancement of 38,65 %. Feed consumption of treatment B was not much different from control, but different than treatment C and D. This trend was also observed in feed palatability, daily growth rate, feed efficiency and protein digestibility. The result of this experiment shows that fermentation may improve azolla leaves nutritional value with the best inclusion level of 30 %.
Keyword: 

Judul: Evaluation of Azolla microphylla as Phytoremediator of Water Quality in Tilapia (Oreochromis niloticus) Reading Environment and its Growth Response
Abstrak: Pengurangan limbah nitrogen pada lingkungan budidaya dapat memanfaatkan teknologi fitoremediasi. Azolla microphylla dapat digunakan sebagai fitoremediator dalam lingkungan budidaya dengan mekanisme rhizodegradation. Penelitian ini bertujuan untuk mengevaluasi pemanfaatan A. microphylla terhadap parameter kualitas air dan respons pertumbuhan ikan nila. Rancangan percobaan yang digunakan adalah rancangan acak lengkap dengan tiga kali ulangan pada setiap perlakuan bobot azolla, yaitu 0, 15, 25, dan 35 g. Penelitian ini menggunakan benih ikan nila berukuran 6,86±0,98 g yang dipelihara dalam akuarium berukuran 100 x 40 x 30 cm bersama dengan tanaman azolla selama 30 hari dengan kepadatan 10 ekor tiap akuarium. Adapun volume air yang digunakan sebanyak 20 L. Hasil penelitian ini menunjukkan bahwa penggunaan bobot azolla sebesar 15 g dan 25 g memiliki konsentrasi amonia, nitrit, nitrat, dan total organic matter (TOM) yang lebih rendah dibandingkan kontrol (P>0,05) pada akhir penelitian. Tingkat kelangsungan hidup (TKH) dan rasio konversi pakan (RKP) tidak menunjukkan perbedaan nyata antar perlakuan (P>0,05), namun laju pertumbuhan spesifik (LPS) menunjukkan kontrol memiliki nilai terendah dibandingkan perlakuan lainnya (P<0,05). Perlakuan 15 g menunjukkan hasil terbaik pada parameter TKH dan RKP, sedangkan nilai LPS terbaik terdapat pada perlakuan 25 g diikuti perlakuan 15 g. Tingkat konsumsi oksigen dan kadar kolesterol cenderung meningkat pada akhir penelitian tetapi masih dalam batas normal. Penggunaan bobot azolla 15 g menunjukkan kinerja terbaik sebagai fitoremediator selama penelitian., Reduction of nitrogen waste in the cultivation environment can utilize phytoremediation technology. Azolla microphylla can be used as a phytoremediator in a aquaculture environment with a rhizodegradation mechanism. This study aimed to evaluate the use of A. microphylla on water quality parameters and growth response of tilapia. The experimental design used was a completely randomized design with three replications for each azolla weight treatment, namely 0, 15, 25, and 35 g. This study used tilapia seeds measuring 6.86 ± 0.98 g which were kept in an aquarium measuring 100 x 40 x 30 cm together with azolla plants for 30 days with a density of 10 fish per aquarium. The volume of water used was 20 L. The results of this study showed that the use of azolla weights of 15 g and 25 g had lower concentrations of ammonia, nitrite, nitrate, and total organic matter (TOM) than control (P> 0.05). at the end of the study. The survival rate (SR) and feed conversion ratio (FCR) did not show significant differences between treatments (P>0.05), but the specific growth rate (SGR) showed that control had the lowest value compared to other treatments (P<0.05). The 15 g treatment showed the best results on the SR and FCR parameters, while the best SGR value was found in the 25 g treatment followed by 15 g treatment. The level of oxygen consumption and cholesterol levels tended to increase at the end of the study but were still within normal limits. The use of azolla weight 15 g showed the best performance as a phytoremediator during the study
Keyword: Azolla microphylla, Fitoremediasi, Ikan nila, Kualitas air, Respons pertumbuhan

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.
Keyword: