Judul: Keragaman curah hujan indonesia saat fenomena indian ocean dipole (iod) dan el nino southern-oscillation (enso)
Abstrak: Fenomena iod (indian ocean dipole) dan enso (el nino-southern oscillation) ditandai dengan adanya perbedaan suhu permukaan laut (spl) dan pergerakan angin zonal maupun meridional yang dapat mempengaruhi anomali curah hujan. Penelitian ini bertujuan untuk menganalisis keragaman curah hujan indonesia saat terjadi fenomena iod, enso, dan kombinasi keduanya serta menjelaskan proses interaksi lautan-atmosfer yang mempengaruhi fenomena tersebut. Data yang digunakan yaitu data bulanan dari noaa dan cru dengan periode waktu 52 tahun (januari 1960-desember 2011). Dengan menggunakan analisis komposit, diperoleh bahwa saat terjadi fenomena iod positif (negatif) dan el nino (la nina) secara bersamaan kondisi curah hujan mengalami penurunan (peningkatan) yang signifikan dibandingkan pada fenomena tunggal. Pada fenomena tersebut perairan indonesia mengalami pendinginan (penghangatan) secara menyeluruh sedangkan wilayah samudera hindia-pasifik mengalami penghangatan (pedinginan). Kondisi ini konsisten dengan tekanan permukaan laut (tpl) yang lebih tinggi di indonesia dibandingkan samudera hindia-pasifik dan angin bergerak dari wilayah indonesia menuju samudera hindia-pasifik, demikian pula sebaliknya. Anomali sirkulasi walker menunjukkan bahwa wilayah indonesia mengalami divergensi sedangkan wilayah samudera hindia-pasifik mengalami konvergensi. Kondisi sebaliknya terjadi pada saat fenomena iod negatif dan la nina.
Keyword: curah hujan indonesia, enso, iod

Judul: The Influence of the ﻿Super Indian Ocean Dipole ﻿(IOD) on Indonesia's Rainfall Anomaly in 2019
Abstrak: Indian Ocean Dipole (IOD) merupakan fenomena interaksi lautan dan atmosfer yang terjadi di kawasan Samudera Hindia. IOD memiliki keterkaitan dengan variasi iklim Indonesia, terutama variabilitas curah hujan. IOD cenderung terjadi bersamaan dengan El-Nino Southern Oscilation (ENSO), Namun hasil penelitian lainnya menemukan bahwa IOD dapat terjadi tanpa diiringi oleh ENSO. Salah satu IOD yang tidak diiringi ENSO adalah IOD (+) 2019. IOD juga memiliki keterkaitan dengan zona konvergensi (ITCZ). Penelitian bertujuan untuk mempelajari kondisi curah hujan Indonesia saat terjadinya IOD (+) 2019 serta keterkaitannya dengan sirkulasi atmosfer dengan menganalisis data-data curah hujan dan atmosfer. Penelitian ini meliputi tahapan analisis klimatologis curah hujan Indonesia, penentuan indeks IOD, analisis korelasi indeks IOD dengan curah hujan Indonesia, analisis anomali curah hujan dan suhu permukaan laut Indonesia tahun 2019, serta analisis klimatologis dan anomali zona konvergensi wilayah Indonesia tahun 2019. Hasil penelitian menunjukan bahwa IOD (+) 2019 menyebabkan penurunan curah hujan Indonesia, terutama saat memasuki periode bulan kering (Juli-September). IOD (+) 2019 juga menyebabkan terjadinya kontraksi/penyusutan ITCZ, sehingga menyebabkan terjadi penurunan curah hujan, terutama di Indonesia bagian Barat., Indian Ocean Dipole (IOD) is a phenomenon of ocean and atmosphere interaction that occurs in the Indian Ocean region. IOD has a relationship with Indonesia's climate variations, especially rainfall variability. IOD tends to occur simultaneously with the El-Nino Southern Oscilation (ENSO), but other studies have found that IOD can occur without ENSO. One of the IODs that is not accompanied by ENSO is IOD (+) 2019. IOD also has a relationship with the convergence zone (ITCZ). This study aims to study the conditions of rainfall in Indonesia during the IOD (+) 2019 and its relationship to atmospheric circulation by analyzing rainfall and atmospheric data. This research includes the stages of climatological analysis of Indonesian rainfall, determination of the IOD index, correlation analysis of the IOD index with Indonesian rainfall, anomaly analysis of rainfall and sea surface temperature in Indonesia in 2019, as well as climatological analysis and anomaly of the convergence zone of the Indonesian region in 2019. The results show that IOD (+) 2019 causes a decrease in Indonesia's rainfall, especially when entering the dry month period (July-September). IOD (+) 2019 also caused a contraction/shrinkage of the ITCZ, causing a decrease in rainfall, especially in western Indonesia.
Keyword: IOD, rainfall, atmospheric circulation, convergence zone

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