Judul: Study of Biphasic Calcium Phosphate Ceramics and HA-Chitosan Composite Implanted into Sheep’s Bone
Abstrak: Biphasic Calcium Phosphate (BCP) biomaterials are recognized as biodegradable, bioresorbable, and osteoconductive material and, therefore, it is suitable for filling bone defects to aid regeneration process of new bone tissue. This study aimed to synthesize BCP ceramics by precipitation method and observe bone growth using BCP ceramics and HA-Chitosan composite implanted into sheep’s bone. BCP ceramics was prepared by precipitation of Na2HPO4.2H2O which was dropped by CaCl2.2H2O at temperature 700C with various molar ratios and various volume of solution. Molar ratio of Ca and P was variated approximately 0.2M:0.2M and 0.334M:0.2M while various volume of solution was 50 ml and 100 ml. BCP ceramics was formed which was indicated by mass of precipitate and the result showed that sample with greater molarity of Ca was resulting in bigger mass precipitate. It showed that higher molarity of Ca/P tends to be more mass precipitate. The X-Ray Diffraction results showed that BCP 100 ml with molar ratio Ca/P about 0.334M:0.2M had the expected characteristics of implant material for in vivo experiment into sheep’s bone. Moreover, it showed the consistency of sample which indicates that it was a reproducible biomaterial. This result was also supported by Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM) characterization. In vivo study of BCP ceramics and HA-Chitosan composite showed that bone recovery without bone graft (control) was more complete than that with BCP and HA-Chitosan bone grafts. Based on pathological evaluation, the results indicated that BCP ceramics was biodegradable and bioresorbable but less osteoconductive. In the contrary, HA-chitosan composite was not biodegradable and bioresorbable but more osteoconductive. Moreover, BCP bone graft was more readily resorbed by the body than HAChitosan. Resorption of HA-Chitosan bone graft was very slow but new tissue growth was faster than that of BCP bone graft. In contrary, resorption of BCP bone graft was very fast but new tissue growth was very slow.
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Judul: Characterization of Biphasic Calcium Phosphate with Ratio of 70/30 Before and After Implanted into Sheep’s Bone
Abstrak: Nowadays, biphasic calcium phosphate is used for biomaterial to cure bone damage. This study focuses only on mixing ratio of 70% mass of hydroxyapatite and 30% mass of tricalcium phosphate with chitosan and acetic acid as the hardening. Pure HA had done by wet precipitation in sintering process at temperature of 900 oC while β-TCP is at temperature of 1000 oC. Mechanical method of BCP is proven to be a non toxic material and could absorb by the mineral body. Implanted BCP was characterized with XRD, FTIR, SEM-EDS and bone characterization with Vickers Hardness. In XRD analysis, the result is adding chitosan makes BCP less accuracy of pure HA and β-TCP. FTIR shows composition of BCP sample with HA, TCP, H2O, AKB, and N-H bending. SEMEDS releases ratio Ca/P of implant in post operation has irregularity caused by interaction with bone that supported by Vickers Hardness number. HV for 1 month of post operation have larger number for both implanted and control bone.
Keyword: β-TCP, HA, BCP

Judul: Karakteristik Massa Air Arlindo Di Pintasan Timor Pada Musim Barat Dan Musim Timur
Abstrak: Pintasan Timor merupakan jalur keluar dari Arlindo (Arus Lintas Indonesia), yaitu arus yang membawa massa air dari Samudera Pasifik melintasi perairan Indonesia menuju Samudera Hindia. Oleh karena itu, Pintasan ini memiliki peranan yang penting dalam sirkulasi massa air khususnya di lintang rendah. Penelitian ini dilaksanakan pada dua periode pengamatan yaitu Januari 2004 (5 stasiun) dan Juni 2005 (6 stasiun). Data yang digunakan adalah data suhu, salinitas, sigma-t, kedalaman, kecepatan dan arah arus. Pengolahan data dilakukan dengan menggunakan perangkat lunak Ocean Data View (ODV), Surfer, dan Matlab untuk memperoleh hasil berupa sebaran melintang dan menegak (suhu, salintas, dan σt), diagram T-S, dan arus Geostropik. Setiap parameter yang diamati memiliki pola pelapisan. Pelapisan ini mengalami perubahan kisaran nilai dan ketebalan pada dua musim yang diamati. Kisaran nilai suhu pada Musim Timur lebih rendah daripada Musim Barat, yaitu mencapai 28.01oC (Juni 2004) dan 29.60 oC (Januari 2005). Pada pelapisan suhu, lapisan homogen yang terbentuk pada Musim Timur lebih tebal daripada Musim Barat yaitu perbedaan ketebalannya mencapai 45 m, namun lapisan termoklin yang terbentuk pada Musim Barat lebih tebal (perbedaan ketebalan mencapai 103 m) daripada Musim Timur. Kisaran nilai salinitas permukaan pada Musim Timur lebih rendah daripada Musim Barat, yaitu mencapai 33.91 psu (Musim Timur) dan 34.33 psu (Musim Barat). Nilai sigma-t di permukaan pada Musim Timur lebih tinggi dari Musim Barat, yaitu berkisar antara 21.20-21.80 (Musim Timur) dan 20.08-21.70 (Musim Barat). Analisis dengan diagram T-S menunjukkan adanya dua jenis massa air, yaitu massa air dicirikan oleh salinitas minimum South Pacific Intermediate Water (SPIW) dan Antarctic Intermediate Water (AAIW). Pengamatan Musim Barat dan Musim Timur tidak ditemukan massa air kerkarakteristik salinitas maksimum baik yang berasal dari massa air Pasifik Utara maupun Pasifik Selatan. Perhitungan arus dengan menggunakan metode geostropik, diketahui bahwa arus di Pintasan Timor bergerak ke arah barat dan timur. Arah arus Geostropik di lapisan permukaan didominasi menuju arah barat baik pada Musim Barat maupun Musim Timur. Transpor massa air pada Musim Barat (Januari 2004) secara menyeluruh bergerak ke arah timur dengan transpor total massa air sebesar 4.61 Sv. Musim Timur (Juni 2005)memiliki transpor total massa air pada sebesar 1.85 Sv dengan total transpor massa air yang bergerak ke timur sebesar 38.92 % dan bergerak ke barat sebesar 61.08 %.
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