Judul: Oceanographic Dynamics  and Simulation of Sea Surface Circulation in the Makassar Strait
Abstrak: Selat Makassar merupakan bagian penting dari perairan global yang menghubungkan Samudera Pasifik dan Samudera Hindia dalam sirkulasi termohalin global dan juga dipengaruhi oleh banyak variabilitas yang ada di Perairan Indonesia. Tujuan dari penelitian ini adalah untuk mendeskripsikan kondisi oseanografi serta pola sirkulasi di Selat Makassar dan analisis trajektori massa air dari pantai Balikpapan. Dalam penelitian digunakan dari model CROCO resolusi 1/36º dengan rentang data 2015-2018 dan model Ichtyop dalam analisis trajektori. Data model digunakan untuk melihat variabilitas suhu, salinitas, arus, dan volume transpor. Hasil dari penelitian menunjukkan dinamika parameter oseanografi berfluktuasi secara musiman hingga kedalaman 60-70 m. Pada musim barat kondisi arus permukaan menuju ke utara. Pada musim timur arus berbalik menuju selatan. Volume transpor dominan terjadi di kedalaman termoklin yang mencapai maksimal ketika musim timur. Analisis trajektori pada permukaan terlihat partikel menyebar mengikuti pola arus musiman yang menuju Laut Sulawesi saat musim barat dan menuju Laut Jawa saat musim timur., Makassar Strait has main role in global circulation connecting Pacific Ocean and Indian Ocean as global thermohaline circulation system. Moreover Makassar Strait also influenced by many variability of Indonesian Seas. The aim of the study is to describe the oceanographic condition and circulation system of Makassar Strait, and analyze the water mass trajectory from Balikpapan coast. This study used CROCO models dataset with 1/36º resolution from 2015-2018 timeseries and Ichtyop model for trajectory analysis. The model dataset is used to observe the dynamic of oceanographic parameters such as temperature, salinity, ocean current, and transport volume. Result of the study revealed the dynamics of oceanographic parameters is fluctuate seasonally up to 60-70 m depth. During Northwest Monsoon (NWM) surface ocean current flows northward. During the Southeast Monsoon (SEM) the surface current flows opposite to the southward, The transport volume is dominated in termocline depth which maximum during SEM. The trajectory analysis at ocean surface revealed the particles spread following the seasonal change. During NWM is dominant flows to the Sulawesi Sea and during SEM flows to the Java Sea.
Keyword: Analisis Trajektori, Model CROCO, Selat Makassar

Judul: Seasonal Variation of Mixed Layer Depth and Thermoclin Thickness using CTD Argo Float Data in Makassar Strait
Abstrak: Selat Makassar berbatasan langsung dengan Laut Sulawesi di bagian utara dan Laut Jawa dan Laut Flores di bagian selatan, dan merupakan jalur utama Arus Lintas Indonesia (Arlindo). Sehingga stratifikasi massa air di Selat Makassar dipengaruhi oleh dinamika dari perairan laut tersebut. Penelitian ini bertujuan untuk mendeskripsikan variasi musiman dari stratifikasi massa air kedalaman lapisan tercampur dan kedalaman lapisan termoklin, dan mengidentifikasi kejadian upwelling pantai di bagian selatan Makassar. Data deret-waktu suhu salinitas kedalaman diperoleh dari pengukuran autonomus CTD Argo Float (ID 5904965) pada periode Desember 2017-November 2018. Hasil penelitian ditemukan massa air North Pacific Subtropical Water (NPSW) dan North Pacific Intermediate Water (NPIW) yang dominan di lokasi studi, dengan ciri salinitas maksimum 34,6-34,7 psu di lapisan termoklin dan salinitas minimum 34,5 psu di lapisan pertengahan. Ditemukannya massa air salinitas rendah dari Laut Jawa juga dominan dalam musim barat di lapisan dekat permukaan. Variasi musiman kedalaman lapisan tercampur di musim barat (DJF) tercatat lebih tebal sekitar 93 m, serta lapisan termoklin lebih tebal di musim timur sekitar 198 m. Perubahan ketebalan kedua lapisan tersebut diduga berkaitan dengan dinamika Arlindo Makassar dan Arus Monsun Jawa, misalnya Arlindo menguat pada musim timur sehingga lapisan termoklin menjadi tebal. Kejadian upwelling pantai pada musim timur (JJA) ditandai dengan penaikan isotherm 27°C, isohaline 34,0 psu dan isopiknal 22,0 kg/m3dari kedalaman sekitar 75 m ke permukaan laut., The Makassar Strait (MS) is directly connected to the Sulawesi Sea in the north and the Java Sea and the Flores Sea in the south, and is the main route of the Indonesian Througflow (ITF). Hence stratification of water mass in the MS is influenced by the dynamics of the sea waters. This study aims to describe seasonal variations of the mixed layer and the thermocline thickness, and to identify the ITF water masses as well as the occurrence of coastal upwelling in the southern part of the MS. Temperature-salinity-depth time series dataset were obtained from oneyear CTD Argo float measurements (ID 5904965) between December 2017- November 2018. The results show that North Pacific water origin of North Pacific Subtropical Water (NPSW) and North Pacific Intermediate Water (NPIW) are dominant, with a maximum salinity characteristic of 34.6-34.7 psu in the thermocline layer and a minimum salinity of 34.5 psu in the intermediate layer. Furthermore, near-surfave fresh Java Sea water appears to be dominant during the northwest monsoon (NWM) period. Seasonal variation of mixed layer depth much deeper (93 m) and much stronger vertical gradient of temperature and salinity due to the presence fresh Java Sea water advevted by the Java Monsoon Current during the NWM period (DJF). However, during the southeast monsoon (SEM) period the mixed layer depth is much shallower and thermocline layer is much thicker (198) m, associated with much stronger the ITF and upwelled colder water from upwelling area. The coastal upwelling event during the SEM period (JJA) in the study area is characterized by an increase of isotherm of 27°C, isohaline of 34.0 psu and isopycnal of 22.0 kg/m3 from 75 m depth to the sea surface layer.
Keyword: CTD Argo Float, ITF, Makassar Strait, Mixed Layer Depth, Thermocline Layer Thickness, Upwelling, Water Masses

Judul: Pengujian Virus Newcastle Disease Gen VII Isolat Lapang Sebagai Virus Standar Pada Uji Tantang Vaksin
Abstrak: This study was conducted to determine the standard of Newcastle disease virus Gene VII field isolate as a virus challenge to vaccine test. A virus suspension that has previously been tested by HA test then titrated with EID50 using 30 Specific Pathogen Free (SPF) of 10 day old chicken embryonated eggs. In addition, chicken lethal dose50 (CLD50) test were used to determine the virus titer that could cause 50% death of the chicken population. The CLD50 test was used 25 day-old-chickens (DOC) divided into 5 groups. The virus was diluted from 10-1 to 10-8. The 104 to 10-8 dilution of NDV was infected to every group of chicken via eyedrop and intranasal with 0.1 ml/chicken dosage. Haemagglutination test showed that the allantoic fluid were contain high titers of NDV is 512 HAU. The infective NDV that had been titrated by EID50 test showed the virus titers is 109 EID50/0.1 ml or 1010 EID50/ml and the virus titers of CLD50 test e.i 106.48 CLD50/0.1 ml or 107.48 CLD50/ml. These results can be concluded that the NDV Gene VII field isolates were most appropriate to be used as a standard virus to vaccine test
Keyword: Newcastle Disease Virus Gene VII, HA tes, EID50 test, CLD50 test