Judul: Infestation and Identification of Bacteria from Cockroach  Periplaneta americana (Dictyoptera: Blattidae) at the Area Around of IPB University, Dramaga
Abstrak: Lipas Periplaneta americana merupakan serangga hama permukiman yang dianggap menjijikan karena sering ditemukan pada lingkungan yang kotor dan berpotensi mencemari makanan dan area sekitarnya. Keberadaan lipas dan bakteri yang terdapat pada ususnya penting untuk diketahui karena berkaitan dengan perannya sebagai vektor. Penelitian ini bertujuan mengukur derajat infestasi lipas dan mengidentifikasi jenis bakteri dalam tubuh lipas di area lingkar kampus IPB Dramaga. Koleksi lipas dilakukan pada bulan Oktober 2022-Januari 2023 menggunakan perangkap berperekat yang dipasang pada malam hari di area permukiman dan rumah makan (kamar mandi atau dapur). Lipas dikelompokkan berdasarkan lokasi penangkapan dan dihitung jumlahnya. Usus lipas diambil dengan cara melakukan pembedahan abdomen untuk dilakukan deteksi bakteri menggunakan PCR (Polymerase Chain Reaction) dan NGS (Next Generation Sequencing). Deteksi keragaman jenis bakteri menggunakan PCR dilakukan terhadap gen target 16S rDNA dengan general primers 61F dan 1227R sedangkan NGS dilakukan menggunakan target V4-V5. Kepadatan lipas tergolong tinggi dengan indeks populasi 2,58 yang melebihi nilai standar baku mutu kesehatan lingkungan. Deteksi bakteri menggunakan PCR menunjukkan hasil negatif, tetapi hasil NGS menunjukkan enam grup bakteri dominan yang terdapat di dalam usus P. americana, yaitu Eubacterium nodatum (7%), Candidatus saccharimonas (6%), Christensenellaceae-R7 (4%), Lactobacillus (4%), Anaerorhabdus furcosa (3%), dan Bacteroides (3%)., Cockroaches Periplaneta americana are resident pest insects that are considered disgusting because they are often found in dirty environments and have the potential to contaminated food and the surrounded areas. The existence of cockroaches and bacteria in the intestine are important to know because cockroaches can serves as a mechanical vectors. This study aims to measure the level of cockroach infestation and identify various species of bacteria in cockroaches gut at area around IPB University, Dramaga. Periplaneta americana were collected in October 2022-January 2023 using sticky traps and placed at night in houses and restaurants (kitchen or bathroom areas). Cockroaches were grouped based on the collection location and counted. The cockroach gut was taken through abdominal dissection for the PCR (Polymerase Chain Reaction) and NGS (Next Generation Sequencing). The diversity of bacteria with gen target 16S rDNA was identified using general primers 61F and 1227R while NGS was identified with V4-V5 targets. The density of cockroaches was high, exceeded the standard of environmental health quality with a population index was 2.58. The PCR test showed negative results, but the NGS result showed the presence of six dominant bacteria group in the gut of P. americana, these were Eubacterium nodetum (7%), Candidatus saccharimonas (6%), Christensenellaceae-R7 (4%), Lactobacillus (4%), Anaerorhabdus furcosa (3%), and Bacteroides (3%).
Keyword: area around of IPB Dramaga, cockroach gut bacteria, Periplaneta americana

Judul: Diversity of Cockroach Blattella spp. (Dictyoptera: Blattellidae) and Detection of Bacteria in Their Digestive Tracts in Campus and Area Around IPB Dramaga
Abstrak: Lipas di dalam lingkup kesehatan memiliki peran penting sebagai vektor mekanik dari berbagai bakteri patogen. Penelitian ini bertujuan untuk mengetahui ragam jenis, derajat infestasi lipas Blattella spp. di kampus IPB Dramaga dan sekitarnya serta ragam jenis bakteri yang terdapat di dalam saluran pencernaannya. Lipas dikoleksi secara manual di permukiman komunal, keluarga, dan kandang. Lipas dikelompokkan berdasarkan parameter lingkungan yaitu tingkat kebersihan, kelembapan, dan pencahayaan. Saluran pencernaan lipas diperoleh melalui pembedahan abdomen untuk dilakukan uji PCR (Polymerase Chain Reaction). Deteksi bakteri dengan target gen 16S rDNA menggunakan primer 61F dan 1227R. Identifikasi kelimpahan bakteri didukung dengan NGS (Next Generation Sequencing). Hasil identifikasi menunjukkan dua jenis lipas, yaitu Blattella germanica dan Blattella nipponica. Derajat infestasi B. germanica tergolong rendah, sedangkan B. nipponica sangat tinggi di luar rumah. Deteksi bakteri menggunakan PCR menunjukkan hasil negatif, namun hasil NGS ditemukan lima bakteri dominan di dalam saluran pencernaan B. germanica, yaitu Christensenellaceae R-7 group (27%), Dysgonomonas (6%), Alistipes (4%), Desulfovibrio (3%), dan RF39 (1%)., Cockroach in the health sphere have an important role as mechanical vectors of various pathogenic bacteria. This study aims to learn the variety of species, the level of cockroach infestation of Blattella spp. at the campus and area around IPB Dramaga and the variety of bacteria species found in the digestive tract. Cockroach were collected manually in communal settlements, families, and cages. Cockroach were grouped based on environmental parameters of cleanliness, humidity and lighting. The digestive tract of cockroach was obtained through abdominal dissection for PCR (Polymerase Chain Reaction) test. Bacteria detection targeted 16S rDNA gene using 61F and 1227R primers. Identification of bacteria was also supported by NGS (Next Generation Sequencing). The identification results showed two types of cockroach, namely Blattella germanica and Blattella nipponica. The degree of B. germanica infestation was low, while that of B. nipponica was very high in the outdoor. Bacteria detection using PCR showed negative results, however the NGS results found five dominant bacteria in the digestive tract of B. germanica, namely Christensenellaceae R-7 group (27%), Dysgonomonas (6%), Alistipes (4%), Desulfovibrio (3%), and RF39 (1%).
Keyword: bacteria, Blattella germanica, Blattella nipponica, cockroach, IPB Dramaga campus

Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition