Judul: Pengaruh Panjang dan Batang Penyusun Kolom terhadap Faktor Tekuk Bambu Andong
Abstrak: Pemanfaatan kayu sebagai bahan konstruksi masih menjadi pilihan utama, sehingga penggunaan bahan alam dengan sifat yang sebanding perlu dilakukan. Bambu andong memiliki sifat yang sebanding dengan kayu sebagai bahan konstruksi. Penelitian ini bertujuan untuk memberikan informasi terkait kapasitas tekuk dan nilai faktor tekuk bambu andong pada kolom tunggal dan multikolom untuk komponen struktur bangunan. Tekuk merupakan peristiwa ketika struktur kolom tidak mampu lagi mempertahankan bentuk aslinya. Nilai kapasitas tekuk tertinggi dimiliki oleh kolom rangkap 4 berukuran panjang 1 meter sebesar 170 kN, sedangkan nilai kapasitas tekuk terendah terdapat pada kolom tunggal dengan panjang 6 meter sebesar 4 kN. Kolom struktur dikatakan aman ketika nilai faktor tekuk empiris yang dianalisis lebih besar dibandingkan faktor tekuk teoritis. Nilai faktor tekuk empiris karakteristik (Rk) dan batas bawah 5% (R0.05) menghasilkan nilai yang lebih tinggi dibandingkan faktor tekuk teoritis pada semua komponennya sehingga aman digunakan dalam analisis struktur., Bamboo has properties comparable to wood as a construction material. Andong bamboo is a natural solid material to be used in the construction world. This study aims to provide information regarding the buckling capacity and buckling factor values of andong bamboo in single and multi-column columns for building structural components. Buckling is an event when the column structure is no longer able to maintain its original shape. The highest buckling capacity value is owned by a double-four column measuring 1 meter in length of 170 kN. In contrast, the lowest buckling capacity value is found in a single column with a length of 6 meters at 4 kN. The structural column is said to be safe when the empirical buckling factor analyzed is greater than the theoretical buckling factor. The empirical buckling factor characteristic capacity (Rk) and the lower limit of 5% (R0.05) produces a higher value than the theoretical
Keyword: Andong bamboo, buckling factor, buckling capacity, column, multicolumn

Judul: Ylinen’s Formula for Estimating the Buckling Capacity of Andong (Gigantochloa pseudoarundinaceae) Bamboo’s Single and Multiple Column
Abstrak: Bambu andong (Gigantochloa pseudoarundinaceae) merupakan jenis bambu yang sangat potensial untuk dikembangkan sebagai kolom karena memiliki dimensi yang besar dan memiliki kapasitas tekan yang cukup tinggi. Formula Ylinen merupakan formula faktor tekuk yang telah terbukti dapat digunakan dalam estimasi kapasitas tekuk berbagai jenis bambu. Penelitian ini bertujuan menguji tingkat akurasi formula Ylinen dalam estimasi kapasitas tekuk kolom tunggal dan ganda bambu andong serta menguji pengaruh panjang dan jumlah batang penyusun kolom ganda terhadap kapasitas tekuk yang dihasilkan. Prosedur pengukuran geometri dan sifat fisis kolom bambu dilakukan dengan mengacu pada BS ISO 22157:2019 dan BS ISO 19624:2018. Pengujian tekuk dilakukan menggunakan UTM Baldwin dan alat uji tekuk bambu panjang di Laboratorium RDBK, Departemen Hasil Hutan, IPB. Analisis data dilakukan menggunakan analisis regresi nonlinier untuk mencari bentuk formula Ylinen terbaik yang dapat digunakan untuk estimasi kapasitas tekuk kolom tunggal. Hasil analisis membuktikan formula Ylinen dapat digunakan untuk estimasi faktor tekuk kolom tunggal bambu andong dengan tingkat akurasi mencapai 86,4%. Hasil estimasi kapasitas tekuk formula Ylinen tidak berbeda secara signifikan dibandingkan pengujian empiris untuk kolom ganda 1 dan 2 meter, namun terlalu rendah untuk kolom ganda 3 meter. Peningkatan jumlah batang penyusun kolom ganda terbukti dapat meningkatkan kapasitas tekuk, sedangkan peningkatan panjang kolom dapat mengurangi kapasitas tekuk., Andong bamboo (Gigantochloa pseudoarundinaceae) is a bamboo species that has potential to be used as a column because it has large dimensions and fairly high compressive capacity. Ylinen’s formula has been proven a reliable buckling factor formula for estimating the buckling capacity of various bamboo species. This study aims to test the accuracy of the Ylinen’s formula for estimating the buckling capacity of single column and multiple column of andong bamboo and examine the effect of length and number of culms that make up multiple column on the buckling capacity. The procedure for measuring geometry and physical properties of bamboo columns refers to BS ISO 22157:2019 and BS ISO 19624:2018. The buckling test used UTM Baldwin and long bamboo buckling test machine at the RDBK Laboratory, Departement of Forest Products, IPB University. Data analysis was performed using nonlinear regression to find the best Ylinen’s formula that can be used to estimate a single column’s buckling capacity. The analysis proves that the Ylinen’s formula can estimate the andong bamboo single column’s buckling factor of with an accuracy rate of 86,4%. The sum of each culm’s member estimated buckling capacity, which is calculated using the Ylinen’s formula, is not significantly different to the empirical test of 1 m and 2 m height multiple columns, but it is too low for 3 m height columns. Increasing the number of culms that make up the multiple column can increase the buckling capacity, while increasing the length of the column reduces the buckling capacity.
Keyword: Andong bamboo, buckling capacity, multiple column, single column, Ylinen’s formula

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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