Judul: Perbandingan Kinerja Enzim Papain Imobil dengan  Berbagai Matriks: Suatu Meta-Analisis
Abstrak: In previous research, papain enzyme was immobilized using various matrices. However, quantitative conclusion about performances of immobilized papain affected by difference of matrices used had not been studied yet. In this research meta-analysis was carried out from 24 literatures with 624 treatments. The matrices compared in this research were alginate, chitosan, magnetic, and silica. The performances parameters analyzed were thermal stability, pH stability, storage stability, repeated usage, and kinetic activity. The analytical method has been used were Standardized Mean Difference (SMD) - subgroup analysis and Kruskal-Wallis. The confidence interval (CI) used was 95%, therefore the significant difference occur if the p-value < 0.05. Immobilized papain with silica had a significant difference with chitosan in thermal stability, pH stability, and storage stability. Silica also had a significant difference with magnetic in storage stability. Magnetic had a significant difference with chitosan in kinetic activity as measured by maximum velocity. Alginate had a significant difference with chitosan and magnetic in kinetic activity as measured by Michaelis-Menten constant. Alginate, chitosan, magnetic, and silica had non-significant difference in repeated usage., Pada penelitian sebelumnya, enzim papain diimobilisasi dengan menggunakan berbagai matriks. Namun demikian, simpulan secara kuantitatif mengenai kinerja papain imobil yang dipengaruhi oleh jenis matriks yang digunakan belum pernah dilaporkan. Penelitian meta-analisis ini dilakukan dengan menggunakan 24 literatur dengan 624 perlakuan. Matriks yang dbandingkan dalam penelitian ini adalah alginat, kitosan, magnetik, dan silika. Parameter kinerja yang dianalisis yaitu stabilitas suhu, stabilitas pH, stabilitas penyimpanan, penggunaan ulang, dan aktivitas kinetik. Metode analisis yang digunakan yaitu Standardized Mean Difference (SMD) – analisis subgroup dan Kruskal-Wallis. Selang kepercayaan yang digunakan yaitu 95%, maka dari itu perbedaan signifikan terjadi apabila nilai-p < 0.05. Papain imobil dengan silika memiliki perbedaan signifikan dengan kitosan dalam stabilitas suhu, stabilitas pH, dan stabilitas penyimpanan. Silika juga memiliki perbedaan signifikan dengan magnetik dalam stabilitas penyimpanan. Magnetik memiliki perbedaan signifikan dengan kitosan dalam aktivitas kinetik yang diukur dengan kecepatan maksimum. Alginat memiliki perbedaan signifikan dengan kitosan dan magnetik dalam aktivitas kinetik yang diukur dengan konstan Michaelis-Menten. Alginat, kitosan, magnetik, dan silika tidak memiliki perbedaan signifikan dalam penggunaan ulang.
Keyword: Kruskal-Wallis, matrices used, meta-analysis, papain immobilization, standardized mean difference

Judul: Pemanfaatan Kitosan dari Cangkang Udang Sebagai Matriks Penyangga pada Imobilisasi Enzim Protease
Abstrak: Udang sebagai salah satu komoditas andalan sektor perikanan, setiap tahunnya mengalami peningkatan produksi. Proses pembekuan udang untuk ekspor, menghasilkan limbah sekitar 60- 70%. Limbah cangkang udang tersebut dapat diolah menjadi kitosan. Kitosan dijadikan sebagai alternatif pilihan pengganti matriks penyangga pada imobilisasi enzim karena kitosan memiliki beberapa keunggulan dibandingkan matriks sintetik lainnya. Keunggulan kitosan yaitu, bentuk fisiknya dapat diubah (serpihan, manik-manik berpori, gel, fiber, membran), biodegradasi, murah, mudah penanganannya, memiliki afinitas yang tinggi pada protein dan non toksik Tujuan penelitian ini adalah untuk memanfaatkan dan mengetahui kemampuan kitosan sebagai matriks penyangga pada imobilisasi enzim protease. Penelitian dilakukan dalam dua tahap yaitu penelitian pendahuluan berupa pembuatan kitosan dan mengukur mutu kitosan yang dihasilkan, meliputi kadar air, kadar abu, kadar nitrogen, viskositas dan derajat deasetilasi. Penelitian utama yaitu imobilisasi enzim protease menggunakan metode Stanley et al. (1975) dengan berbagai perlakuan kitosan (0 g; 0,1 g; 0,2 g; 0,3 g; 0,4 g; 0,5 g; 0,6 g; 0,7 g; 0,8 g; 0,9 g dan 1 g) dan dilanjutkan dengan uji kualitatif untuk mengukur aktivitas enzim dan aktivitas spesifik enzim imobil. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL) dengan dua kali ulangan. Kitosan yang dihasilkan pada penelitian telah memenuhi standar mutu kitosan yang ditetapkan oleh PROTAN Jepang. Parameter mutu kitosan meliputi, kadar abu sebesar 0%, kadar air 7%, kadar nitrogen 4,93%, derajat deasetilasi 95,3% dan viskositas sebesar 39,5%. Hasil analisis data terhadap aktivitas enzim papain imobil, diperoleh ada satu perlakuan kitosan yang memberi pengaruh berbeda nyata terhadap aktivitas enzim imobil yaitu perlakuan 1 g kitosan, sedangkan pada enzim bromelin imobil tidak ada perlakuan kitosan yang memberikan pengaruh berbeda nyata. Aktivitas enzim papain imobil terkecil diperoleh pada perlakuan 0,6 g kitosan yaitu sebesar 0,0113 U/ml/menit dan aktivitas tertinggi sebesar 0,0190 U/ml/menit pada perlakuan 1 g kitosan. Aktivitas enzim bromelin imobil tertinggi juga diperoleh pada perlakuan 1 g kitosan yaitu 0,0108 U/ml/menit, sedangkan aktivitas terkecilnya diperoleh pada perlakuan 0,1 g kitosan dengan aktivitas 0,0011 U/ml/menit. Aktivitas spesifik enzim papain imobil tertinggi yaitu sebesar 0,1432 U/mg protein enzim diperoleh pada perlakuan 1 g kitosan, sedangkan aktivitas spesifik enzim terendah diperoleh pada perlakuan 0,7 g kitosan dengan aktivitas spesifik 0,0940 U/mg protein enzim. Aktivitas spesifik enzim bromelin imobil terkecil diperoleh pada perlakuan 0,1 g kitosan dengan aktivitas 0,0036 U/mg protein enzim, sedangkan aktivitas spesifik enzim imobil tertinggi yang dihasilkan sebesar 0,0733 U/mg protein enzim diperoleh pada perlakuan 1 g kitosan.
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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