Judul: Keterkaitan perubahan arah dan kecepatan angin dengan pola hujan harian di DKI Jakarta dan sekitarnya: Studi kasus tahun 1994
Abstrak: DKI Jakarta terletak di pantai Utara P. Jawa dengan garis pantai membentuk teluk menunjukkan adanya pola konvergen saat terjadi angin darat dan pola divergen saat terjadi angin laut. Pola konvergen saat terjadi angin darat menyebabkan curah hujan harian tertinggi di daerah ini biasanya pada malam atau menjelang pagi hari. Selain angin laut dan darat, sistem angin yang berpengaruh di DKI Jakarta dan sekitarnya adalah monsun. Dampak angin monsun adalah adanya angin Baratan (Oktober - Maret) yang cenderung membawa massa udara dingin yang lembab sehingga menimbulkan banyak hujan dan angin Timuran yang membawa massa udara kering sehingga tidak mendatangkan hujan. Penelitian ini menganalisa hubungan angin pada beberapa level pengamatan (permukaan, 330 m, 660 m, 990 m dan 1650 m) di Stasiun pengamatan angin Cengkareng dan Curug dengan curah hujan harian di Stasiun Klimatologi Halim PK, Ciledug dan Serpong. Komponen angin dipisahkan menjadi dua yaitu; angin Zonal (Barat-Timur) dan Meridional (Utara- Selatan). Hubungan angin Zonal maupun Meridional dengan curah hujan harian antar stasiun dibagi atas dua waktu yaitu; siang dan malam hari. Analisa hubungan angin Zonal maupun Meridional dengan curah hujan barian antar stasiun pengamatan menggunakan korelasi linear yang dibantu oleh perangkat pengolah data Statistika (Statistica Ver. 5) dan menghitung nilai peluang berdasarkan nilai koefisien korelasi untuk uji taraf nyata. Hasil analisis tersebut menunjukkan sebagian besar memiliki hubungan yang tidak nyata. Namun ada yang menunjukkan hubungan nyata (± 20 %), sebagian besar terjadi pada level pengamatan angin 330 m, 660 m, dan 990 m saat angin Zonal pada kedua Stasiun pengamatan angin dengan curah hujan harian di Stasiun Halim PK dan Ciledug. Sehingga dapat dikatakan bahwa besarnya curah hujan harian (mm) di DKI Jakarta dan sekitarnya lebih ditentukan oleh angin pada level 330 m, 660 m dan 990 m.
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Judul: Analisis Karakteristik Aerosol Optical Depth (AOD) dan Curah Hujan di DKI Jakarta (Studi Kasus: Tahun 2015)
Abstrak: Penelitian mengenai peran aerosol dalam sistem iklim telah banyak dilakukan. Aerosol dapat mempengaruhi pola presipitasi dengan cara memodifikasi distribusi ukuran tetesan awan dan umur tinggal awan. Penambahan konsentrasi aerosol yang besar ke awan tropis laut dapat menunda pembentukan hujan di awan. Penelitian ini bertujuan untuk menganalisis karakteristik serta fluktuasi nilai aerosol optical depth (AOD) dan curah hujan di DKI Jakarta pada tahun 2015. Studi kasus ini dipilih sebab fluktuasi curah hujan yang tinggi yang ditandai dengan terjadinya banjir pada tahun tersebut dan adanya perbedaan total presipitasi yang signifikan antara bulan basah dan bulan kering diharapkan mampu menggambarkan hubungan antara AOD dengan curah hujan. Hasil yang diperoleh dari penelitian ini menunjukkan bahwa nilai AOD maksimum adalah 0,994 dan nilai minimum adalah 0,017, serta curah hujan harian tertinggi sebesar 98,3 mm. Penelitian ini menggunakan nilai parameter suhu udara dan kecepatan angin sebagai faktor yang mempengaruhi terjadinya curah hujan. Hasil analisis korelasi yang diperoleh dari penelitian ini menunjukkan bahwa aerosol optical depth berkorelasi negatif dengan curah hujan dan berkorelasi positif dengan suhu udara dan kecepatan angin., There has been a lot of research about the role of aerosols in the climate system. Aerosol affect precipitation pattern by modifying the cloud drop size distribution and cloud residence time. The addition of large aerosol concentrations to marine tropical clouds can delay the formation of rain in the cloud. This study aims to analyze the characteristics and fluctuations of aerosol optical depth (AOD) and rainfall in DKI Jakarta in 2015. This case study was chosen because of the high fluctuations in rainfall which was marked by the occurrence of 2015’s floods, and the significant difference in total precipitation between wet and dry months is expected to be able to describe the relationship between AOD and rainfall. The results obtained from this study indicate that the maximum AOD value is 0.994 and the minimum value is 0.017, and the highest daily rainfall is 98.3 mm. This study uses the parameter values of air temperature and wind speed as factors that influence the occurrence of rainfall. The results of the correlation analysis obtained from this study indicate that aerosol optical depth is negatively correlated with rainfall and positively correlated with air temperature and wind speed.
Keyword: aerosol, AOD, precipitation, temperature, wind speed

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