Judul: Land Cover Change in Leuwiliang District, Bogor  Regency During 2015 and 2020 Using Landsat Image 8
Abstrak: Pertambahan jumlah penduduk mengakibatkan perubahan pemanfaatan tata guna lahan yang ada di Kecamatan Leuwiliang. Perubahan pemanfaatan tata guna lahan dapat diketahui dengan cara menganalisis perubahan tutupan menggunakan citra Landsat 8 (OLI) perekaman tahun 2015 dan 2020. Metode klasifikasi tutupan lahan dilakukan menggunakan klasifikasi terbimbing yang kemudian dilakukan analisis perubahan tutupan lahan dengan cara membandingkan hasil klasifikasi tahun 2015 dan 2020. Klasifikasi tutupan lahan menghasilkan 8 kelas tutupan lahan yang dapat terindentifikasi berupa badan air, pertanian lahan basah, pertanian lahan kering, lahan terbangun, lahan kosong, perkebunan, hutan, dan semak belukar. Hasil klasifikasi menunjukkan nilai akurasi yang tinggi sebesar 94,49% pada Kappa Accuracy. Perubahan peningkatan luas kelas tutupan lahan paling tinggi terjadi pada kelas pertanian lahan kering sebesar 1481,42 ha, sedangkan perubahan penurunan luas kelas tutupan lahan paling tinggi terjadi pada kelas hutan sebesar 2503,14 ha., Increased population in Leuwiliang District has resulted in changes in land usage. Changes in land use can be detected by studying cover changes between 2015 and 2020 using Landsat 8 (OLI) data. The land cover classification process is carried out using a supervised classification, which is then compared to the results of the 2015 and 2020 classifications to determine land cover changes. Land cover classification provides 8 different land cover classes: water bodies, wetland agriculture, dry land agriculture, developed land, vacant land, plantations, forests, and shrubs. The categorization findings indicate a high level of accuracy, with a Kappa Accuracy of 94.49%. The greatest change in land cover class occurred in the dry land agricultural class, which encompassed 1481.42 ha, whereas the greatest change in land cover class occurred in the forest class, which encompassed 2503.14
Keyword: citra satelit resolusi sedang, klasifikasi terbimbing, Leuwiliang, uji akurasi

Judul: Land Using Sentinel-2 Imagery in Sukamakmur District, Bogor Regency from 2018-2023
Abstrak: Pertumbuhan penduduk yang pesat mengakibatkan tingkat kebutuhan masyarakat terhadap lahan semakin meningkat sehingga menyebabkan terjadinya perubahan tutupan lahan. Penelitian ini bertujuan untuk mengidentifikasi dan menganalisis perubahan tutupan lahan di Kecamatan Sukamakmur Kabupaten Bogor menggunakan Citra Sentinel-2 tahun 2018–2023. Terdapat 9 kelas tutupan lahan yaitu hutan, sawah, kebun campuran, pertanian lahan kering, pemukiman, lahan terbuka tanah, semak, sungai, dan danau. Kelas tutupan lahan yang mengalami peningkatan adalah tutupan lahan hutan (83,40 ha), pertanian lahan kering (48,94 ha), sawah (6,35 ha), dan permukiman (1,08 ha). Sedangkan kelas tutupan lahan yang mengalami penurunan adalah kelas tutupan lahan semak belukar (80,97 ha), lahan terbuka (40,01 ha), dan perkebunan campuran (18,79 ha). Perubahan tutupan lahan yang terjadi di Kecamatan Sukamakmur Kabupaten Bogor menunjukkan sebesar 73,86% mengalami perubahan ke arah positif dan 26,14% mengalami perubahan ke arah negatif. Perubahan ke arah positif yang lebih besar menunjukkan bahwa cadangan karbon di Kecamatan Sukamakmur semakin meningkat sehingga tanaman mampu menyerap CO2 dari atmosfer lebih banyak dan menyimpannya dalam bentuk biomassa tanaman., Rapid population growth results in the level of people's need for land increasing, causing changes in land cover. This research aims to identify and analyze changes in land cover in Sukamakmur District, Bogor Regency using Sentinel-2 Imagery in 2018–2023. There are 9 land cover classes, namely forest, rice fields, mixed gardens, dry land agriculture, settlements, open land, bushes, rivers, and lakes. The land cover classes that experienced an increase were forest land cover (83.40 ha), dry land agriculture (48.94 ha), rice fields (6.35 ha), and settlements (1.08 ha). Meanwhile, the land cover classes that experienced a decline were the land cover classes of shrubs (80.97 ha), open land (40.01 ha), and mixed plantations (18.79 ha). Land cover changes that occurred in Sukamakmur District, Bogor Regency showed that 73.86% experienced changes in a positive direction and 26.14% experienced changes in a negative direction. Changes in a greater positive direction indicate that carbon reserves in Sukamakmur District have increased so that plants are able to absorb more CO2 from the atmosphere and store it in the form of plant biomass.
Keyword: tutupan lahan, sentinel-2, Sukamakmur

Judul: Pemurnian dan karakterisasi protein inhibitor RNA helikase virus hepatitis C
Abstrak: Hepatitis C virus (HCV) infection is the second most common chronic viral infection in the world with global prevalence. This infection is contribution to chronic hepatitis and liver cirrhosis, often leading to hepatocellular carcinoma. There is no effective drug and vaccine available against HCV. The current standard treatment, a combination of pegylated interferon-α with ribavirin, is limited by its suboptimal response rate in a significant patient population, side effects, and affordability. Therefore, development of effective drug is needed. One approach to find out the candidate of antiviral drug is to discover the inhibitor of enzyme that essential for virus replication, such as RNA helicase. Streptomyces chartreusis 5-095 produce the inhibitor of HCV RNA helicase. The aim of this study was to purify the protein inhibitor which has inhibition activity against ATPase activity of RNA helicase HCV from S. chartreusis 5-095. The supernatant of culture S. chartreusis 5-095 exhibited high inhibiton activity against ATPase activity of RNA helicase HCV (approximately 72%) at 10 days of incubation. The extracellular protein inhibitor was partially purified by procedures of precipitation with ammonium sulfate to 65% saturation and gel filtration (Sephadex G50) using methanol water solution (4:6) as an eluen. The purity of protein inhibitor was monitored by SDS PAGE. The protein inhibitor showed a relative molecular mass were estimated to be 14 kDa and increased the purity 23,08 fold than those of the crude protein. The specific activity and IC50 after purification were 13,1338 U/mg and 0,0767 mg/mL, respectively. The activity of purified protein inhibitor showed its stability over pH range from 5-8 and optimum at pH 7,4. The inhibition activity showed its stability up to 70% at temperature 100 oC. The purified protein inhibitor relatively stable its activity at storage in the range of -20 oC to room temperature for 35 days.
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