Judul: Slow-release urea in rice straw based diets to increase efficiency of bali cattle production
Abstrak: Urea merupakan sumber nitrogen bukan protein (NPN) yang paling sering digunakan untuk menggantikan sebagian dari protein ransum pada ruminansia. Namun karena urea bersifat mudah terhidrolisis menjadi amoniak di dalam rumen dan dengan cepat pula diserap memasuki sistem darah, maka dalam praktiknya penggunaan urea dapat berdampak negatif bagi ternak, mulai dari penurunan konsumsi dan performa ternak sampai kematian akibat keracunan urea. Upaya untuk mengoptimalkan nilai guna dari urea sebagai sumber NPN yang ekonomis bagi ruminansia harus mempertimbangkan dampak negatif dari sifat urea tersebut. Pada penelitian ini, upaya tersebut diwujudkan dengan menguji tiga macam produk urea lepas-lamban, yakni: urea-seng sulfat (US), urea-zeolit (UZ), dan urea-seng sulfat-zeolit (USZ) yang diuji dalam tiga tahap (preparasi dan penentuan sifat produk, in vitro, dan in vivo). Penelitian tahap pertama bertujuan mempelajari kelarutan preparat US, UZ, dan USZ sebagai suplemen sumber NPN lepas-lamban pada ruminansia. Pada tahap ini, zeolit dipanaskan pada suhu 100 0C lalu kerapatan ruah dan keporiannya diukur untuk menentukan daya serapnya. Selanjutnya, urea dicampurkan dengan zeolit, seng sulfat, atau zeolit dan seng sulfat dengan metode pelelehan urea pada suhu 80 – 110 0C. Rasio urea:zeolit ditetapkan berdasarkan daya serap zeolit, sedangkan rasio urea:seng sulfat ditetapkan berdasarkan reaksi pembentukan kompleks urea-seng sulfat. Produk yang dihasilkan lalu dipindai dengan scanning electron microscopy untuk mengetahui tingkat ketercampuran antara zeolit dan urea. Produk tersebut dilarutkan dalam larutan McDougall dan kelarutan nitrogennya diukur pada rentang waktu: 0, 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 10, 12, 24, dan 48 jam. Rancangan percobaan yang digunakan untuk uji kelarutan ini adalah Rancangan Acak Lengkap dan setiap perlakuan terdiri atas 2 ulangan.
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Judul: Evaluation of Balanced Urea and Nitrate Ratio with Slow  Release Urea Nitrate (SRUN) as Ruminant Feed Additive: In Vitro
Abstrak: Rendahnya kandungan protein dari bahan pakan menjadi salah satu faktor penghambat peningkatan produktivitas ternak ruminansia. Oleh karena itu, perlu adanya suplementasi protein pada pakan ternak ruminansia agar protein pada ternak dapat terpenuhi sehingga ternak berproduksi secara optimal. Urea dan nitrat merupakan sumber NPN yang biasa diberikan pada pakan tambahan ruminansia. Urea merupakan NPN yang digunakan sebagai pengganti pakan protein murni, karena memiliki harga yang terjangkau dan dapat menekan biaya pakan ternak. Sedangkan Nitrat (NO3 - ) adalah penghambat metana yang efektif dan sumber NPN potensial untuk ternak, bertindak sebagai penyerap H2 dan menambahkan nitrogen berbasis amonia ke rumen. Pemanfaatan urea dan nitrat dalam nutrisi ruminansia terbatas karena hidrolisisnya yang cepat menjadi amonia dalam rumen, sehingga perlu dilakukan teknologi pelapisan atau coating dengan polimer lain seperti zeolit dengan metode SRUN yang dapat mengontrol degradasi urea-nitrat dan pelepasan NH3 ke dalam rumen. Penelitian ini bertujuan mengembangkan inovasi SRUN, serta mengevaluasi imbangan rasio urea-nitrat sebagai pakan aditif ruminansia yang berfungsi untuk stimulator sintesis protein mikroba rumen dengan metode in vitro. Penelitian ini menggunakan rancangan acak kelompok (RAK) dengan 11 perlakuan dan 4 kelompok sebagai ulangan. Data dianalisis menggunakan ANOVA dan diuji lanjut dengan uji Duncan menggunakan software SPSS 25. Hasil penelitian menunjukkan pengaruh berbeda nyata (P<0,05) terhadap parameter yaitu kecernaan bahan kering dan bahan organik, pH, produksi gas total, gas metan, NH3, dan sintesis protein mikroba. Hasil terbaik seluruh parameter seperti kecernaan, pH, produksi gas, gas metan, NH3, sintesis protein, populasi mikroba, mikroba, dan VFA ditunjukkan oleh perlakuan P2 dan P10. Disimpulkan bahwa perlakuan P2 (P0 + Coating nitrat 2%) dan P10 (P0 + Coating urea:nitrat (2:1) 4%) dapat menjadi agen mitigasi metana dan menjadi stimulator sintesis protein mikroba rumen., The low protein content of feed ingredients is one of the inhibitors for increasing the productivity of ruminants. Therefore, there is a need for protein supplementation in ruminant feed so that the protein in livestock can be fulfilled and produced optimally. Urea and nitrate are NPN sources that are usually given to ruminant feed additives. Urea is an NPN that is used as a substitute for pure protein feed, because it has an affordable price and can reduce the cost of animal feed. Nitrate (NO3 - ) is an effective methane inhibitor and a potential NPN source for livestock, acting as an H2 sink and adding ammonia-based nitrogen in the rumen. Utilization of urea and nitrate as ruminant feed is limited due to the rapid hydrolysis into ammonia in the rumen. So, it is necessary to apply coating technology using polymers such as zeolite using the SRUN method, which can control the degradation of urea-nitrate and the release of NH3 into the rumen. This study aims to develop innovative SRUN, as well as evaluate the balance of the urea-nitrate ratio as a feed additive for ruminants which functions as a stimulator of rumen microbial protein synthesis using in vitro methods. This study used a randomized block design (RBD) with 11 treatments and 4 groups as replications. Data were analyzed using ANOVA and further tested with Duncan's test using SPSS 25 software. The results showed a
Keyword: ammonia, coating urea-nitrate, non-protein nitrogen, zeolite

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