Judul: The Effect of ENSO to the Variability of Wet Season Onset in Indonesia
Abstrak: The transition in Indonesia is affected by ENSO. This study aims to determine the distribution of wet season onset in Indonesia and to understand the effect of ENSO to the variability of wet season onset in Indonesia. Wet season onset in every year is determined based on local rainfall. Index Nino 3.4 is determined from 1978-2007 and correlation analysis is used to measure the relation between the generated index with the index from NOAA. The analysis shows a positive correlation coefficient (r = 0,87). El Nino years consists of 1982, 1987, 1991, 1997, 2002, meanwhile La Nina consists of 1978, 1980, 1981, 1983, 1984, 1988, 1989, 1995, 1996, 1998, 1999, 2000, 2001, 2005, 2007. The results show that ENSO affect the wet season onset in various magnitude in every area of Indonesia. El Nino composite shows that the wet season onset shifts for 94 days later from normal years in Ambon meanwhile in Banda Aceh the onset shifts for 10 days earlier. La Nina composite shows that wet season onset shifts for 74 days earlier from normal years in Surabaya, meanwhile it is constant in Banda Aceh. Keywords: ENSO, index Nino 3.4, rainfall ,wet season onset, Perubahan musim dimulai pada satu waktu yang disebut sebagai onset. Perubahan musim di Indonesia dipengaruhi oleh ENSO. Penelitian ini bertujuan menentukan sebaran onset musim hujan secara spasial di Indonesia serta mengetahui pengaruh ENSO terhadap variabilitas onset musim hujan di Indonesia. Onset musim hujan setiap tahun ditentukan dengan kriteria curah hujan lokal. Indeks Nino 3.4 ditentukan dari tahun 1978-2007. Analisis korelasi antara indeks yang dihasilkan dan indeks dari NOAA menghasilkan koefisien korelasi positif sebesar (r = 0,87). Tahun El Nino di antaranya adalah 1982, 1987, 1991, 1997, 2002, sedangkan tahun La Nina diantaranya 1978, 1980, 1981, 1983, 1984, 1988, 1989, 1995, 1996, 1998, 1999, 2000, 2001, 2005, 2007. Hasil penelitian menunjukkan bahwa ENSO memberikan pengaruh yang beragam terhadap onset musim hujan di setiap wilayah di Indonesia. Pada komposit tahun El Nino terjadi pergeseran onset musim hujan yang sebesar 94 hari lebih lambat dari tahun normal di Ambon sedangkan pada Banda Aceh justru bergeser sebesar 10 hari lebih cepat. Pada komposit tahun La Nina terjadi pergeseran onset musim hujan sebesar 74 hari lebih awal dari tahun normal pada wilayah Surabaya sedangkan pada Banda Aceh menunjukkan onset musim hujan konstan atau tidak bergeser. Kata kunci: curah hujan, ENSO, indeks Nino 3.4, onset musim hujan.
Keyword: Curah Hujan, ENSO, Indeks Nino 3.4, Onset Musim Hujan, Rainfall, Index Nino 3.4, Wet Season Onset

Judul: Analisis Variabilitas Curah Hujan Indonesia pada Kejadian ENSO
Abstrak: Indonesia is one of the countries which experiences El Niño and Southern Oscillation (ENSO) impact on rainfall variability. The purpose of this study included to investigate the Indonesian climate variations related to ENSO events and to understand the effect of ENSO on rainfall temporal distributions at Indramayu (6.35°LS, 108.32°BT) and Tabing (0.88°LS, 100.35°BT). Composite analysis method was used to reveal the trend of sea surface temperature anomaly, wind at 850 hPa, OLR and TRMM 3B43 rainfall data, whereas temporal and correlation analysis was used to observe rainfall and nino-3.4 index. When El Niño sea surface temperature anomaly (ASPL) maximum in October-December, 850 hPa wind backwards from west to east along with increased speed and deviation of OLR below the average values in central and eastern equatorial Pacific which indicates the accumulation of rain cloud. La Niña occurrence is indicated by the deviations of sea surface temperature below average. Low pressure center in Asia reached 850 hPa winds and strengthened Walker circulation, the movement of the air mass brought moisture to Indonesia. Based on the composite of TRMM rainfall, it appeared that the El Niño events gave more significant impact at the end of the year (October to December) on East Indonesia, Java and parts of Sumatra and Kalimantan, while La Niña (December to February) in south and eastern part of Indonesia. Monsoonal pattern (Indramayu) showed ENSO impacts more strongly than equatorial (Tabing). The shift of dry season and low rainfall were affected by ASPL fluctuations on nino-3.4 region.
Keyword: TRMM, SPL, Rainfall, OLR, ENSO

Judul: Synthesis of Chicken Eggshells-Based β-Tricalcium Phosphate Bioceramics and Their Biocompatibility Test as A Tooth Filler
Abstrak: Preservation of alveolar bone following tooth extraction is an important step in dental practices before dental implant placement. This study reported synthesis of β-Tricalcium Phosphate (β-TCP) bioceramics and its biocompatibility test as a tooth filler to maintain the desired alveolar ridge dimension and stimulate the bone healing processes in the area of tooth loss. β-TCP bioceramics was resulted directly from precipitation of calcinated chicken eggshells as calcium source and phosphoric acid. The corresponding β-TCP was mixed with chitosan 2% to get β-TCP pellet for biocompatibility testing. Biocompatibility testing of β-TCP on lower incisor was performed in rabbits and sheep as animal model. In this study, the x-ray diffraction (XRD) profiles showed that 1000 oC calcinated chicken eggshells correspond to calcium oxide (CaO). There was also transformation phase of CaO into Ca(OH)2 observed after more than three months stored. The XRD profiles proved that obtained β-TCP bioceramics by precipitation has the same pattern with that of reference data base and commercial β-TCP. Fourier transform infrared (FTIR) spectra were completely consistent with the result of crystallization processes observed by XRD measurements. Moreover, the purity of the product shown by the atomic absorption spectroscopy (AAS) resulted in Ca/P ratio of 1.48 which was closed to that of standard β-TCP ceramics. The repeatable XRD peaks patterns and FTIR spectra obviously showed the sample reproducibility. Sheep’s alveolar socket that is filled with the corresponding β-TCP demonstrated the expected results. The x-ray radiograph of sheep’s jaw indicated no change on mesio-distal of the edentulous area. Moreover, the histological results were completely consistent with the x-ray radiograph and macroscopic result which is proved by the formation of new bone. In the contrary with sheep’s result, histological results showed no tooth growth on rabbit proved by the presence of lipid and collagen on the extraction site. This result did not correspond to the x-ray radiograph and macroscopic results that demonstrated the tooth growth and erupted tooth. It is clear that the corresponding β-TCP could minimize the bone loss and maintain the dimension of alveolar ridge.
Keyword: β-tricalcium phosphate, chicken eggshells, rabbit, sheep, tooth filler