Judul: Distribusi hemaglutinin streptococcus agalactiae pada sapi penderita mastitis subklinis
Abstrak: Proses adhesi merupakan tahap awal yang harus dilalui bakteri untuk menginfeksi sel inang. Kemampuan adhesi suatu bakteri erat hubungannya dengan patogenesis penyakit yang disebabkan oleh bakteri tersebut. Kemampuan S. agalactiae mengaglutinasi eritrosit in vitro, dapat digunakan sebagai model untuk mempelajari intereaksi mikroba dan sel inang. Tujuan penelitian ini adalah untuk melihat distribusi hemaglutinin S. agalactiae pada sapi perah penderita mastitis subklinis. Sebanyak 32 isolat S. agalactiae dilihat kemampuan hemaglutinasi dengan suspensi 4% eritrosit sapi, ayam, domba dan kuda. Beberapa isolat S. agalactiae asal sapi menunjukan aktivitas hemaglutinasi, dari 32 isolat diperoleh 12 isolat yang menunjukan hemaglutinasi positif minimal terhadap satu jenis eritrosit yang digunakan dan 20 isolat yang menunjukan hemaglutinasi negatif.
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Judul: Studi tentang sifat streptococcus agalactiae yang diisolasi dari susu sapi mastitis subklinis
Abstrak: Streptococcus agalactiae adalah agen utama penyebab mastitis subklinis pada sapi perah. Tujuan penelitian ini adalah untuk mengetahui sifat S. agalactiae yang diisolasi dari sapi perah. Sampel diuji duga keberadaan S. agalactiae dengan uji Christie, Atkins, Munch-Petersen (CAMP), uji grouping, penanaman dalam media soft agar (SA), dan media serum soft agar (SSA). Sampel yang diuji adalah bakteri kokus yang bersifat Gram positif dan katalase negatif. Dari 57 isolat yang diuji, 34 isolat menujukkan hasil yang positif terhadap uji CAMP. Dari isolat yang positif uji CAMP diidentifikasi sebanyak 14 isolat S. aglactiae dengan uji grouping. Isolat S. agalactiae ditanam ke dalam media SA dan SSA, sebanyak 8 isolat tumbuh dengan koloni berbentuk difus dan 6 isolat lainnya tumbuh dengan bentuk koloni kompak. Berdasarkan hasil penelitian ini, kultur S. agalactiae yang berasal dari susu sapi mastitis subklinis positif terhadap uji CAMP dan mengekspresikan bentuk fenotip permukaannya pada media SA dan SSA.
Keyword: Characteristics, S. Agalactiaes, Subclinical mastitis, Cow milk, Bogor Agricultural University

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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