Judul: Efektivitas Penambahan Multi Enzim pada Pakan terhadap Kinerja Pertumbuhan Benih Ikan Patin Pangasius hypophthalmus
Abstrak: Ketersediaan enzim dalam pakan mampu meningkatkan kecernaan pakan dan penyerapan nutrien, sehingga pemanfaatan pakan akan lebih efisien untuk meningkatkan pertumbuhan. Penelitian ini bertujuan mengevaluasi penambahan multi enzim pada pakan terhadap kinerja pertumbuhan benih ikan patin Pangasius hypophthalmus. Penelitian ini menggunakan rancangan acak lengkap dengan empat perlakuan pakan dengan dosis penambahan multi enzim yang berbeda, yaitu 0, 1, 2, dan 3 g kg-1 pakan. Ikan patin yang digunakan memiliki ukuran panjang rata-rata 1,00 ± 0,07 inci dengan bobot rata-rata 0,12 ± 0,04 g. Ikan dipelihara di akuarium berukuran 50 × 40 × 35 cm dengan kepadatan 3 ekor L-1 air. Ikan diberi pakan sebanyak empat kali sehari (07.00, 10.00, 13.00, dan 16.00 WIB) dengan metode at satiation selama 30 hari pemeliharaan. Berdasarkan hasil penelitian, dapat disimpulkan bahwa penambahan multi enzim pada pakan mampu meningkatkan pertumbuhan benih ikan patin.
Keyword: ikan patin, multi enzim, pertumbuhan

Judul: Penambahan Nukleotida pada Pakan untuk Meningkatkan Kinerja Pertumbuhan Benih Ikan Patin Pangasianodon hypophthalmus
Abstrak: Nukleotida merupakan suatu senyawa biologi yang memiliki peran penting dalam hampir semua proses biokimia seluler. Tujuan penelitian ini adalah mengevaluasi pengaruh penambahan nukleotida dengan dosis berbeda pada pakan terhadap pertumbuhan benih ikan patin Pangasianodon hypophthalmus pada fase pendederan. Penelitian ini menggunakan rancangan acak lengkap dengan empat perlakuan yaitu pakan tanpa diberi nukleotida, pakan dengan tambahan 0,5% nukleotida, pakan dengan tambahan 1% nukleotida, dan pakan dengan tambahan 1,5% nukleotida dengan empat kali pengulangan. Ikan yang digunakan memiliki panjang rata-rata 0,7 ± 0,006 inci dan bobot rata-rata 0,11 ± 0,002 g. Ikan dipelihara dalam akuarium dengan dimensi 50x50x40 cm3 dengan ketinggian air 20 cm. Ikan diberi pakan empat kali sehari (07.00, 10.00, 13.00, dan 16.00 WIB) dengan metode at satiation selama 30 hari pemeliharaan. Hasil penelitian menunjukkan bahwa penambahan nukleotida tidak berpengaruh nyata terhadap tingkat kelangsungan hidup ikan. Penambahan nukleotida pada pakan sebanyak 1,5% memberikan kinerja pertumbuhan yang lebih baik dengan bobot akhir mencapai 1,9 kali lipat dari perlakuan tanpa pemberian nukleotida.
Keyword: nukleotida, patin, pertumbuhan

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite