Judul: Uji Patogenisitas Bakteri Vibrio parahaemolyticus pada Udang Vaname Litopenaeus vannamei
Abstrak: Salah satu penyakit yang sering menyerang budidaya udang adalah vibriosis, yang disebabkan oleh infeksi bakteri Vibrio sp. termasuk Vibrio parahaemolyticus. Strain tertentu V. parahaemolyticus yang memiliki gen pirA pirB menjadi penyebab penyakit acute hepatopankreatic nekrosis disease (AHPND). Penelitian ini bertujuan untuk menguji patogenisitas bakteri V. parahaemolyticus pada udang vaname. Uji tantang dilakukan dengan menggunakan udang vaname berukuran 0.9±0.1 g dengan kepadatan bakteri (104 CFU mL-1 ) yang didapat dari uji LC50. Penelitian menggunakan rancangan acak lengkap dengan tiga perlakuan dan tiga ulangan, yaitu udang vaname yang tidak diinfeksi V. parahaemolyticus (K), udang vaname yang diinfeksi V. parahaemolyticus dari Tasikmalaya (Vp-1), dan udang vaname yang diinfeksi V. parahaemolyticus dari Situbondo (Vp-2). Parameter yang diamati terdiri atas konfirmasi V. parahaemolyticus dan AHPND, tingkat mortalitas, gejala klinis, populasi bakteri, total haemocyte count, aktivitas fagositik, respiratory burst, aktivitas phenoloxydase, serta histopatologi hepatopankreas dan usus. Isolat Vp-1 dan Vp-2 teridentifikasi sebagai V. parahaemolyticus strain AHPND yang menginfeksi udang vaname dengan gejala klinis berupa hepatopankreas yang pucat, usus kosong, serta pergerakan tidak aktif. Kerusakan pada tingkat jaringan terlihat banyak nekrosis pada organ hepatopankreas dan usus, serta menyebabkan kematian hingga 73,33-81,67% dengan rata-rata waktu kematian 24,28-65,44 jam., A disease that often affects shrimp farming is vibriosis, which is caused by infection with Vibrio sp. including Vibrio parahaemolyticus. A specific strain of V. parahaemolyticus that has the pirA pirB gene causes acute hepatopancreatic necrosis disease (AHPND). This study aims to test the pathogenicity of V. parahaemolyticus bacteria in white shrimp. The challenge test was conducted using shrimp measuring 0,9 ± 0,1 g with bacterial density (10^4 CFU mL-1) obtained from the LC50 test. The study used a completely randomized design with three treatments and three replicates, namely white shrimp not infected with V. parahaemolyticus (K), white shrimp infected with V. parahaemolyticus from Tasikmalaya (Vp-1), and white shrimp infected with V. parahaemolyticus from Situbondo (Vp-2). Parameters observed consisted of confirmation of V. parahaemolyticus and AHPND, mortality rate, clinical signs, bacterial population, total haemocyte count, phagocytic activity, respiratory burst, phenoloxydase activity, and hepatopancreas and gut histopathology. Isolates Vp-1 and Vp-2 were identified as V. parahaemolyticus strain AHPND infecting white shrimp with clinical signs of pale hepatopancreas, empty gut, and inactive movement. Damage at the tissue level showed a lot of necrosis in the hepatopancreas and gut, and caused mortality up to 73,33-81,67% with an average mortality time of 24,28-65,44 hours.
Keyword: AHPND, histopathology, pathogenicity, V. parahaemolyticus, white shrimp

Judul: Experimental Models of Vibrio parahaemolyticus Infection in White Leg Shrimp Litopenaeus vannamei
Abstrak: Penyakit Vibriosis disebabkan oleh bakteri genus Vibrio. Penyebaran penyakit pada organisme budidaya dapat terjadi secara horizontal maupun vertikal. Penyebaran penyakit secara vertikal terjadi karena perpindahan dari induk ke benur, sedangkan penyebaran secara horizontal terjadi akibat penyebaran dari satu udang ke udang lain. Penelitian ini bertujuan mengevaluasi dampak transmisi penyakit AHPND secara horizontal melalui media pemeliharaan dan kanibalisme. Penelitian dilakukan menggunakan rancangan acak lengkap (RAL) yang terdiri dari tiga perlakuan serta tiga kali ulangan. Pada perlakuan kanibalisme (Kan), udang sehat diberi pakan udang mati yang terkonfirmasi membawa V. parahaemolyticus. Pada perlakuan kohabitasi (Koh), udang diinfeksi V. parahaemolyticus dengan metode injeksi dan dipelihara bersama udang sehat dengan pembatas berupa hapa, serta pada perlakuan kontrol, udang diberi pakan komersial. Parameter yang diuji yaitu kematian kumulatif, gejala klinis, identifikasi bakteri Vibrio sp., konfirmasi AHPND menggunakan metode PCR, dan histopatologi. Kematian kumulatif hingga akhir pemeliharaan mencapai 83,33±20,82% pada penularan melalui kanibalisme dan 6,67±11,55% melalui kohabitasi. Gejala infeksi V. parahaemolyticus ditemukan dengan kondisi hepatopankreas yang berwarna pucat. Udang pada perlakuan yang terkonfirmasi positif V. parahaemolyticus strain AHPND dengan kepemilikan gen toksin PirA dan PirB dengan terbentuknya pita DNA yang teramplifikasi pada 230 bp. Histopatologi yang terlihat pada udang yang terinfeksi V. parahaemolyticus strain AHPND adalah terjadinya pengelupasan sel epitel tubulus hepatopankreas secara massif yang dimulai dari pusat hepatopankreas dan berlanjut ke luar ke daerah embrionik. Penyakit yang disebabkan oleh V. parahaemolyticus lebih mudah ditransmisikan melalui kanibalisme dibanding dengan melalui kohabitasi atau hidup bersama., Vibriosis is caused by bacteria of the genus Vibrio. Disease spread in aquaculture organisms can occur horizontally or vertically. Vertical spread of the disease occurs due to transfer from broodstock to fry, while horizontal spread occurs due to spread from one shrimp to another. This study aims to evaluate the impact of horizontal transmission of AHPND disease through rearing media and cannibalism. The study was conducted using a completely randomized design (CRD) consisting of three treatments and three replications. In the cannibalism treatment (Kan), healthy shrimp were fed dead shrimp confirmed to carry V. parahaemolyticus. In the cohabitation treatment (Koh), shrimp were infected with V. parahaemolyticus by injection method and kept with healthy shrimp with a barrier in the form of a hapa, and in the control treatment, shrimp were fed commercial feed. The parameters tested were cumulative mortality, clinical symptoms, identification of Vibrio sp. bacteria, confirmation of AHPND using the PCR method, and histopathology. Cumulative mortality until the end of rearing reached 83.33 ± 20.82% in transmission through cannibalism and 6.67 ± 11.55% through cohabitation. Symptoms of V. parahaemolyticus infection were found with pale hepatopancreas. Shrimp in the treatment were confirmed positive for V. parahaemolyticus strain AHPND with the possession of PirA and PirB toxin genes with the formation of a DNA band amplified at 230 bp. Histopathology seen in shrimp infected with V. parahaemolyticus strain AHPND is a massive exfoliation of hepatopancreatic tubular epithelial cells starting from the center of the hepatopancreas and continuing outward to the embryonic region. The disease caused by V. parahaemolyticus is more easily transmitted through cannibalism than through cohabitation.
Keyword: cannibalism, cohabitation, experimental models, Vibrio parahaemolyticus, white leg shrimp

Judul: Elektrodeposisi Film Tipis Semikonduktor Cu2ZnSnS4 (CZTS) pada Substrat Kaca ITO
Abstrak: Semiconductor Cu2ZnSnS4 (CZTS) thin film that can be used as absorber layers on solar cell module was made via electrodeposition method. CZTS thin film was electrodeposited on the surface of a silicate glass coated with a thin layer of indium tin oxide (ITO). Deposition process was done using potentiostatic mode at room temperature with a potential of 1.05 V for 30, 45, and 60 minutes, followed with annealing the film at 2 different temperatures, 500 ºC using furnace and 180 ºC using hot plate, both treatments for 45 minutes in N2/H2S atmosphere. The X-ray difractograms were analyzed using Match 2 program and showed that the CZTS thin films had kesterit crystalline structure, with a low percentage of CZTS phase. The thin film also contained secondary phases such as Cu2S, ZnS, and SnS. The obtained CZTS thin films had a thickness between 1.039 and 1.676 μm. Absorption study showed that the band gap energy of CZTS thin films which was annealed using furnace ranged from 1.50 to 1.52 eV, whereas that annealed using the hot plate was not observed. The band gap energy value showed that CZTS thin films can be used as sunlight absorber layers on solar cell. The formation of CZTS crystal film on this investigation was effectively performed using furnace annealing process at a temperature of 500 ºC with deposition time of 45 minutes.
Keyword: Thin film, Electrodeposition, Cu2ZnSnS4