Judul: Pengaruh mutasi terhadap bakteri proteolitik Bacillus pumilus (Y1)
Abstrak: Protease bakteri merupakan salah satu jenis enzim yang diproduksi oleh industri fermentasi pada skala tinggi dan sudah dimanfaatkan dalam industri deterjen serta berbagai industri lain, seperti industri bir dan anggur, kue dan roti, produk-produk daging dan ikan, industri pakan ternak, dan industri penyamak kulit. Untuk memproduksi enzim bakteri yang bernilai komersial tinggi, dipergunakan galur khusus dengan sifat-sifat unggul, yang masih dapat diperbaiki lagi dengan menggunakan teknik mutasi dan seleksi. Penelitian ini bertujuan untuk menghasilkan mutan dari Bacillus pumilus (Y1) yang mempunyai produktivitas enzim protease lebih tinggi dibandingkan dengan tipe liarnya. Mutasi dilakukan dengan dua cara yaitu (1) mutasi dengan iradiasi sinar ultraviolet (sinar UV) dan (2) mutasi dengan penambahan etilmetansulfonat (EMS). Sebelum diiradiasi dengan sinar UV, dilakukan penye- garan kultur stok B. pumilus (Y1) pada media LB; selan- jutnya sel bakteri dipisahkan/disentrifusa; endapan sel bakteri diresuspensikan dalam "phosphat buffer saline"...
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Judul: Ekspresi Gen Protease Bacillus pumilus Y1 dalam Escherichia coli DH5alfa : Orientasi Gen dan Pengaruh Penambahan IPTG (Isopropilthiogalaktosida)
Abstrak: Bacillus pumilus Y1 yang diisolasi dari limbah cair tahu di Indonesia diketahui menghasilkan protease s e ~ p asu btilisin (Likumahwa, 1993; Ristiarini, 1996). Gen penghasil protease serupa subtilisin berukuran 3 kilo pasangbasa (kb) telah dicoba diklon dari B. pwnilus Y1 ke &lam Escherichia coli DH5a (Naibaho, 1997). Gen baukwan 3 kb tersebut dipotong dengan enzim restriksi EcoRI, diligasikan pada vektor pUC19, dan ditransformasikan ke &lam E. coli DH5a. Plasmid rekombinan yang dihasiikan disebut pBN1. Ekspresi protease dari pBNl temyata tidak sebaik protease asalnya. Untuk itu, dilakukan penelitian untuk mempelajari orientasi gen dan pengaruh penambahan IPTG (isopropilthiogalaktosida) terhadap ekspresi gen tersebut, dengan harap akan memperbaiki ekspresi dan meningkatkan produksi enzimnya.
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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