Judul: Aktivitas Antibakteri dan Sediaan Masker Peel Off Berbahan Spirulina platensis terhadap Bakteri Propionibacterium acne.
Abstrak: Spirulina platensis merupakan mikroalga kelompok cyanobacteria yang mengandung senyawa aktif dan berpotensi sebagai antibakteri. Tujuan penelitian ini yaitu menentukan aktivitas antibakteri terhadap P. acne dari ekstrak S. platensis kultur dan komersial, serta sediaan masker peel off yang mengandung ekstrak dan biomasa S. platensis. Tahapan penelitian meliputi kultivasi, pemanenan S. platensis, ekstraksi senyawa aktif, dan aplikasi S. platensis sebagai sediaan masker peel off berbahan polivinil alkohol, hydroxy propyl methyl cellulose, metil paraben, gliserin serta analisis aktivitas antibakteri. Kultivasi S. platensis menggunakan media organik. Biomasa S. platensis diekstraksi menggunakan etanol PA 96%, selanjutnya dianalisis fitokimia. Analisis aktivitas antibakteri dilakukan dengan ekstrak S. platensis dan sediaan masker peel off. Aktivitas antibakteri ekstrak S. platensis hasil kultur dengan konsentrasi 2 mg/mL, 4 mg/mL dan 8 mg/mL berturut-turut yakni 4.63±0.35 mm, 8.81±0.08 mm, 9.56±0.26 mm, sedangkan aktivitas antibakteri dalam sediaan masker peel off terhadap bakteri P. acne yakni 10±0.35 mm.
Keyword: antibakteri, organik, Propionibacterium acne, Spirulina platensis

Judul: Aktivitas antibakteri Spirulina platensis terhadap bakteri penyebab jerawat dan karakteristik masker berbasis Spirulina dan kolagen.
Abstrak: Penelitian ini menggunakan Spirulina yang dikultur dalam media media organik (pupuk Urea, Plant Catalyst dan RI1) dan kolagen dari kulit ikan kakap merah. Tujuan penelitian menentukan karakteristik Spirulina, karakteristik kolagen serta karakteristik fisik, kimiawi dan mikrobiologis sediaan masker. Tahapan penelitian meliputi kultivasi dan pemanenan S. platensis, ekstraksi biomasa menggunakan etanol, ekstraksi kolagen menggunakan pelarut NaOH dan asam asetat serta formulasi masker. Analisis meliputi fitokimia, rendemen, aktivitas antibakteri, analisis sensori, homogenitas, viskositas, daya sebar dan total mikroba. Ekstrak S.platensis mampu menghambat bakteri penyebab jerawat Staphylococcus aureus, Stapylococcus epidermidis serta Propionibacterium acne dengan diameter zona hambat terbesar pada ekstrak 100 μg/sumur. Kolagen ikan kakap berwarna putih, dengan rendemen sebesar 6.4±0.28%, dan pH 6.46±0.15. Sediaan masker yang dihasilkan memiliki nilai sensori berkisar 3.57- 4.23 dalam kategori suka, homogen, daya sebar 6.6±0.28, viskositas 2500±70.71, pH 6.29±0.06, dan total mikroba <1x10 cfu/g. Sediaan masker mampu menghambat bakteri penyebab jerawat S. aureus, S. epidermidis serta P. acne.
Keyword: antibakteri, kolagen, masker, Spirulina platensis

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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