Judul: Aktivitas enzimatik dan respirasi pada tanah tercemar pestisida yang diberi serbuk jerami dan bakteri pendegradasi nitril
Abstrak: Bahan organik seperti jerami diperlukan oleh mikrob tanah diperlukan untuk memperbaiki struktur tanah yang rusak akibat sistem pengelolaan tanah, misalnya pemberian pestisida. Selain bahan organik, bakteri pendegradasi nitril juga mempunyai peranan dalam memperbaiki struktur tanah yang rusak akibat pestisida. Bakteri ini menggunakan gugus nitril dari pestisida Decis dan Antracol sebagai sumber energi.
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Judul: dentification of Nitrilase Gene Existence in Soil Sample Using Metagenomic Approach.
Abstrak: Nitrilase merupakan enzim yang berperan dalam biotransformasi senyawa nitril (R-CN) secara langsung, sehingga menghasilkan asam karboksilat dan amonia. Selama dekade terakhir ini, beberapa proses pada bidang farmasi maupun industri mengarah kepada proses biotransformasi dengan enzim nitrilase dibandingkan dengan sintesis kimiawi. Beberapa bakteri yang dilaporkan memiliki enzim nitrilase, antara lain Rhodococcus, Grobacterium, dan Pseudomonas. Penelitian ini bertujuan mengidentifikasi keberadaan gen nitrilase dari sampel tanah dengan pendekatan metagenomik. Tiga bakteri kontrol nitrilase dianalisis dengan metode polymerase chain reaction (PCR) menggunakan primer yang telah didesain (H1F-H1R). Deteksi gen nitrilase dengan menggunakan primer H1F-H1R terhadap ketiga isolat bakteri yang telah terbukti memiliki kemampuan dalam biotransformasi senyawa asetonitril menjadi asam asetat menunjukkan bahwa ketiga isolat bakteri tersebut mengandung fragmen gen nitrilase. Keberadaan gen nitrilase dalam tanah dapat diidentifikasi dengan ekstraksi DNA secara langsung dan amplifikasi gen nitrilase dengan primer H1F-H1R. Hasil analisis dengan BLASTN memperlihatkan bahwa fragmen DNA yang diamplifikasi dengan primer H1F-H1R mempunyai homologi yang tinggi yaitu sebesar 98% terhadap Rhodococcus rhodochrous strain tg1-A6 nitrilase gene. Hasil amplifikasi dan sekuensing fragmen DNA ini menunjukkan bahwa keberadaan gen nitrilase pada sampel tanah dapat diidentifikasi dengan pendekatan metagenomik.
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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