Judul: Aplikasi Bacillus subtilis 1BG2, Ekstrak Meniran, dan Kombinasinya untuk Pencegahan Penyakit Koinfeksi Bakterial pada Gurami
Abstrak: Penyakit yang menyerang ikan gurami dapat disebabkan bakteri patogen Aeromonas hydrophila dan Enterobacter cloacae. Penelitian ini bertujuan untuk mengevaluasi efektivitas aplikasi ekstrak meniran, probiotik Bacillus subtilis 1BG2, dan kombinasinya untuk pencegahan koinfeksi A. hydrophila YH1 dan E. cloacae YH2 pada ikan gurami. Ikan uji yang digunakan berukuran 10,63±0,80 g dan diberi pakan komersial yang telah diberi perlakuan suplementasi. Penelitian ini terdiri dari lima perlakuan dan tiga ulangan yaitu K- (tanpa diberi probiotik dan tanpa disuntik bakteri koinfeksi), K+ (tanpa diberi probiotik dan disuntik bakteri koinfeksi), A (diberi ekstrak meniran dan disuntik bakteri koinfeksi), B (diberi probiotik 1BG2 disuntik bakteri koinfeksi), C (diberi probiotik 1BG2 dan ekstrak meniran disuntik bakteri koinfeksi. Ikan diuji tantang dengan koinfeksi A. hydrophila YH1 dan E. cloacae YH2. Hasil penelitian menunjukkan setelah uji tantang ikan gurami yang diberi perlakuan suplementasi memiliki tingkat kelangsungan hidup yang berbeda nyata (P<0,05) dibandingkan k+. Laju pertumbuhan harian dan rasio konversi pakan perlakuan suplementasi berbeda nyata (P<0,05) dibandingkan perlakuan kontrol. Perlakuan ekstrak meniran, probiotik B. subtilis 1BG2, dan kombinasi dengan pemberian melalui pakan menghasilkan tingkat kelangsungan hidup tinggi dan memberi respons baik pada gambaran darah untuk mencegah koinfeksi A. hydrophila YH1 dan E. cloacae YH2, meskipun demikian ketiga perlakuan suplementasi tidak memberikan pengaruh yang berbeda.
Keyword: Aeromonas hydrophila YH1, B. subtilis 1BG2, Ekstrak meniran, Enterobacter cloacae YH2, Koinfeksi

Judul: Suplementasi Probiotik Bacillus cereus BR2, Bacillus subtilis 1BG2, dan Kombinasinya untuk Pencegahan Penyakit Ko-infeksi Bakterial pada Gurami
Abstrak: Wabah penyakit gurami di Bogor disebabkan oleh ko-infeksi Aeromonas hydrophila YH1 dan Enterobacter cloacae YH2. Penggunaan probiotik merupakan alternatif untuk mengendalikan ko-infeksi. Penelitian ini bertujuan untuk mengevaluasi efektivitas suplementasi probiotik Bacillus cereus BR2, Bacillus subtilis 1BG2, dan kombinasinya untuk pencegahan ko-infeksi pada gurami. Ikan uji berukuran 10.63±0.80 g diberi pakan komersial yang telah diperkaya probiotik. Penelitian terdiri dari lima perlakuan dan tiga ulangan yaitu K- (tanpa probiotik dan tanpa diinjeksi A. hydrophila + E. cloacae), K+ (tanpa probiotik dan diinjeksi A. hydrophila + E. cloacae), A (B. cereus BR2 dan diinjeksi A. hydrophila + E. cloacae), B (B. subtilis 1BG2 dan diinjeksi A. hydrophila + E. cloacae), C (B. cereus BR2 + B. subtilis 1BG2 dan diinjeksi A. hydrophila + E. cloacae). Hasil penelitian menunjukkan respons imun gurami (sel darah merah, sel darah putih, hemoglobin, dan aktivitas fagositik) setelah diberi perlakuan suplementasi B. cereus BR2, B. subtilis 1BG2, dan kombinasinya lebih baik dan berbeda nyata (P<0.05) dibandingkan kontrol. Setelah uji tantang, sintasan dan respons imun gurami yang diberi probiotik lebih baik dan berbeda nyata (P<0.05) dibandingkan K+. Pemberian probiotik B. cereus BR2, B. subtilis 1BG2, dan kombinasinya memberikan efektivitas terbaik untuk pencegahan ko-infeksi A. hydrophila YH1 dan E. cloacae YH2.
Keyword: Aeromonas hydrophila YH1, Bacillus cereus BR2, Bacillus subtilis 1BG2, Enterobacter cloacae YH2, respons imun

Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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