Judul: Verifikasi Metode Ekstraksi Fenol Kloroform untuk Isolasi DNA pada Daging dan Produk Olahan
Abstrak: Ekstraksi DNA yang merupakan prosedur rutin dalam analisis molekular menjadi titik kritis dan sangat mempengaruhi hasil analisis. Salah satu metode ekstraksi yang banyak digunakan adalah metode fenol kloroform. Verifikasi terhadap metode ini sangat diperlukan untuk membuktikan bahwa laboratorium yang bersangkutan mampu melakukan pengujian menggunakan metode tersebut dengan hasil yang valid. Penelitian ini bertujuan memverifikasi metode ekstraksi DNA metode fenol kloroform pada daging segar dan daging olahan dengan menggunakan presisi ketertiruan (repeatibility), keseksamaan (reproducibility), dan ketangguhan metode (ruggedness). Tolak ukur analisis ini adalah kemurnian DNA yang diukur menggunakan spektrofotometer nanodrop. Berdasarkan hasil penelitian, uji presesi ketertiruan (repeatibility) yang dilakukan oleh seorang laboran dan uji presisi keseksamaan (reproducibility) yang dilakukan tiga analis yang berbeda menunjukkan nilai simpangan baku relatif (SBR) di bawah 5% pada tiap sampel yang diuji. Hal ini menunjukkan bahwa metode ekstraksi yang digunakan memiliki nilai presisi yang baik, sehingga hasil yang didapat akan sama walaupun dilakukan berulang dan oleh analis yang berbeda. Berdasarkan uji ketangguhan yang dilakukan menunjukkan bahwa volume fenol dan klororform isoamil alkohol (CIAA) optimal yang diberikan yaitu masing-masing 400 μL, serta bobot sampel yang digunakan yaitu 0.075 g untuk meningkatkan efisiensi metode.
Keyword: ekstraksi DNA, fenol kloroform, ketangguhan, presisi, verifikasi

Judul: Validasi metode ekstraksi DNA pada analisis DNA babi dalam produk bakso
Abstrak: There are many cases of fraud meat-based food products found in our society. Polymerase chain reaction (PCR) technique has been developed as a precise and quick method to identify meat species both from raw meat and from meat products. Extraction is the critical level on PCR analysis because it was very related with the quality of the isolated DNA. Therefore, validation of extraction method was carried out in this research to ensure that the extraction results had good DNA qualities. The validated extraction method was then tested for its sensitivity to detect the contamination of pork meat in meatball products made with various pork contamination and also in meatball products sold in Bogor. The validation results showed that the DNA extraction method had detection limit of DNA purity of 0.117, quantitation limit of DNA purity of 0.389, relative standard deviation of 2.31%, and uncertainty of DNA purity of (1.93 ± 0.04). The pork contamination could still be detected up to 0.5% (w/w) contamination and no pork contamination found in meatball samples from 3 market in Bogor (Pasar Anyar, Pasar Bogor, and Pasar Warung Jambu)
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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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