Judul: Proyeksi Perubahan Pola Curah Hujan Di Indonesia Menggunakan Skenario Perubahan Iklim Jangka Pendek
Abstrak: Penelitian ini mengkaji tentang perubahan curah hujan berdasarkan skenario perubahan iklim jangka pendek untuk periode proyeksi tahun 2011-2035. Perhitungan model prediksi dilakukan dengan menggunakan metode analisis korelasi kanonik. Data yang dipakai adalah data curah hujan dari observasi BMKG, CHIRPS dan luaran model GCM. Hasil penelitian menunjukan bahwa data CHIRPS cukup baik dalam menduga curah hujan Indonesia, yakni terlihat dari nilai rataan korelasi 24 stasiun (r=0.715) dan plot data yang mampu mengikuti pola data observasi. Berdasarkan analisis cluster, wilayah Indonesia terbagi menjadi lima wilayah cluster dengan karakter curah hujan yang berbeda. Analisis klimatologi menunjukan bahwa perubahan curah hujan rata-rata yang cukup besar terjadi pada musim JJA dan DJF, sementara pada MAM dan SON perubahannya kecil. Analisis curah hujan per-cluster menunjukan terjadinya perubahan curah hujan yang signifikan pada semua cluster. Proyeksi iklim jangka pendek secara umum menunjukan bahwa Indonesia akan mengalami kenaikan curah hujan rata-rata saat musim kemarau dan penurunan saat musim hujan.
Keyword: analisis cluster, GCM, korelasi kanonik

Judul: Proyeksi Perubahan Curah Hujan Ekstrim Di Indonesia Berdasarkan Skenario Representative Concentration Pathways (RCP).
Abstrak: Perubahan iklim mempengaruhi fenomena iklim/ cuaca di berbagai belahan dunia yang berdampak pada berbagai aktivitas kehidupan manusia, salah satunya yaitu curah hujan ekstrim. Tujuan penelitian ini adalah menganalisis intensitas dan peluang curah hujan ekstrim pada periode tahun 1981-2005 (baseline), serta perubahannya pada periode tahun 2011-2035 (proyeksi) di Indonesia. Proyeksi curah hujan ekstrim dilakukan berdasarkan skenario perubahan iklim Representative Concentration Pathways (RCP). Nilai curah hujan ekstrim diidentifikasi menggunakan parameter Generalized Extreme Value (GEV), serta perubahan wilayah dan peluang kejadian ekstrim dianalisis menggunakan analisis cluster dan Probability Density Function (PDF). Berdasarkan hasil model proyeksi curah hujan ekstrim dengan parameter GEV, secara umum terjadi peningkatan nilai parameter lokasi (μ), dan penurunan nilai parameter skala (σ), serta proyeksi parameter bentuk (ξ) yang cenderung negatif. Hal ini menunjukkan bahwa peluang curah hujan ekstrim dengan intensitas tinggi diproyeksikan akan cenderung semakin meningkat. Hasil proyeksi juga menunjukkan bahwa berdasarkan analisis cluster dan PDF, wilayah dengan intensitas dan peluang curah hujan ekstrim yang tinggi semakin meluas. Secara keseluruhan terdapat tren peningkatan curah hujan ekstrim pada periode 2011-2035 dengan kecenderungan curah hujan ekstrim akan lebih sering terjadi, lebih luas, dan meningkat intensitasnya dibandingkan periode 1981-2005.
Keyword: curah hujan ekstrim, perubahan iklim, skenario RCP

Judul: Extracellular Expression of thermostable Geobacillus stearothermophilus T1.2RQ Lipase for Biodiesel Production
Abstrak: The extracellular expression of enzymes in an excellent secretion host such as Bacillus subtilis is a useful strategy for making enzymes of industrial significance more affordable by lowering the cost of its downstream processing. Lipases are a category of hydrolases that catalyze the hydrolysis of triglycerides to glycerol and free fatty acids. Also, lipases catalyze the hydrolysis and transesterification of other esters as well as the synthesis of esters. They can perform very specific biotransformation reactions and are widely used in food, organic synthesis, detergents, cosmetic, and pharmaceutical industries. Geobacillus stearothermophilus T1.2RQ lipase is an industrially-desired thermostable lipolytic enzyme with an excellent hydrolytic and transesterification activity. This study aimed to express T1.2RQ lipase, in B. subtilis WB800 and ensure its secretion into the extracellular medium. Three signal peptides (AmyQ, Epr, LipA) and two promoters (Pgrac01 and Pgrac100) were used in the secretory-expression of T1.2RQ lipase, based on five constructed expression vectors constructed by restriction cloning and PCR mutagenesis. Sangers sequencing was used to verify constructs to ensure they are in the correct reading frame. Recombinants vectors, pHT43 (plasmid control), pHT43-T1.2RQ, pHT43- T1.2RQ_AmyQ, pHT43-T1.2RQ_Epr, and pHT43-T1.2RQ_LipA, were transformed by electroporation into Bacillus subtilis WB800. The electroporation was successful with the optimum condition of 2500V, 200 ohms, 25µF, and 5milliseconds. Recombinant B. subtilis pHT43 (negative control) and pHT43-T1.2RQlip + signal peptides were streaked on the lipidic agar, LA+TBN. All four recombinants, including the negative control (B. subtilis WB800-pHT43), produced clear zones on the TBN agar plate after overnight incubation (fig 2), indicating the presence of a lipolytic enzyme in all of the recombinant B. subtilis cells. pHT43-T1.2RQlip + signal peptides (AmyQ, Epr, and LipA) have clear zones with significantly higher diameters than B. subtilis WB800-pHT43 (negative control). This phenomenon suggests that the recombinant thermostable lipase T1.2RQ introduced into these cells was successfully expressed, thereby increasing the lipolytic capability of its host cells T1.2RQ lipase was expressed in 50ml terrific broth medium (TB) and the expression induced with 1mM IPTG. Lipase activity assay using p-nitrophenyl esters showed that all three signal peptides directed the secretion of T1.2RQ lipase into the extracellular medium. Signal peptide, LipA, resulted in the highest extracellular activity of 5.6 U/mL, which corresponds to a 6-fold increase over the parent B. subtilis WB800 strain. Meanwhile, signal peptides, AmyQ and Epr produced 4.2 U/mL and 3.4 U/mL activity respectively. SDS-Zymogram analysis confirmed that T1.2RQ lipase was correctly processed and secreted in its original size of 44 kDa. An attempt to further increase lipase expression level by promoter optimization showed that, contrary to expectation, promoter Pgrac100 exhibited similar expression levels as the original Pgrac01. Nevertheless, the demonstration of the successful secretion of T1.2RQ lipase in this work confirms the latter as a promising approach for the industrial production of the enzyme
Keyword: Bacillus subtilis, Expression, Extracellular, Heterologous, Lipase, Thermostable