Judul: Pengaruh Substrat, Inhibitor, dan Aktivator terhadap Protease  Bacillus pumilus Y1 dan Xanthomonas campestris pathovar glycines 1FL dan YR32
Abstrak: lnfonnasi sifat-sifat biokimiawi enzim seperti ketahanan terhadap lingkungan, pH dan suhu optimum, dan sifat biokimiawi lain seperti substrat yang cocok bagi enzim, aktivator, inhibitor, nilai KM dan Vmax, diperlukan untuk pemanfaatan enzim secara optimal tnaupun untuk studi molekular.
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Judul: Ketahanan panas enzim protease dari Xanthomonas campestris pathovar glycines
Abstrak: Protease termasuk enzim yang berperan besar dalam industri, terutama protease mikroba, sehingga banyak penelitian mengenai protease dilakukan, terutama mengenai ketahanan panasnya. Protease mikroba memegang peranan penting karena terbukti dapat diproduksi dengan lebih efisien. Xanthomonas campestris pv. glycines adalah salah satu bakteri patogen tanaman yang penting, yang selama ini digunakan dalam industri sebagai penghasil gum xanthan. Bakteri Gram negatif asli Indonesia yang dapat menghasilkan protease ekstraselular antara lain merupakan strain dari X. campestris pv. glycines, yaitu X. campestris pv. glycines IFL, YR32, YR60, YR64 dan YR69.. Penelitian ini bertujuan untuk menentukan strain dari X. campestris pv. glycines yang dapat menghasilkan protease dengan daya tahan panas yang baik serta untuk melihat pengaruh dari beberapa senyawa kimiawi, khususnya CaCl2, KCl dan Triton X-100, terhadap daya tahan panasnya. Pada tahap awal pengukuran aktivitasnya selama pemanasan pada suhu 50°C, 60°C dan 70°C menggunakan filtrat kasar enzim, dimana diperoleh hasil bahwa protease 1FL, YR32, YR60 dan YR64 ternyata mempunyai ketahanan panas yang baik. Selanjutnya pengukuran penambahan senyawa kimiawi (CaCl2, KCl dan Triton X-100) terhadap aktivitas protease dilakukan setelah filtrat kasar diendapkan dengan amonium sulfat untuk memperoleh data yang lebih akurat. Penambahan CaCl₂ ternyata kurang mempengaruhi ketahanan panas enzim protease pada suhu 50°C sehngga pengukuran pada suhu yang lebih tinggi tidak dilakukan. Penambahan KCI 15 mM juga tidak berpengaruh terhadap kestabilan aktivitas protease 1FL, YR32, YR60 selama pemanasan 60°C, sedangkan penambahan triton X-100 sebanyak 10% (v/v) ternyata dapat mempertahankan aktivitas proteolitiknya pada pemanasan 60°C dan 70°C sampai 24 jam. Hal ini menunjukkan potensi X. campestris pv. glycines, terutama X. campestris pv. glycines 1FL, sebagai penghasil protease tahan panas.
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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