Judul: Pengamatan Makroskopis Biodegradasi Implan Logam Berbahan Dasar Besi pada Mencit
Abstrak: Biodegradation of metal implants is metal corrosion process due to the reaction between the metal with the substances in the environment, especially the environment of the body. The aim of this study is to examine the biodegradation behavior of iron based metal implants in mice. This study used 40 adult male ddy mice 30-35g. Mice were divided into 4 groups, Fe (iron wire) n=12, Fe-Cr (iron coated by chromium) n=12, SS 316L (stainless steel) n=12, and control (n=4). The implantation of materials was placed the hip area/intramuscularly (IM) and thigh area/subcutaneously (SC). Macroscopic study of biodegradation iron based metal implants were material changes examination, evaluation of carat formed, the corrosion rate, and the weight loss. The result showed the greatest damage occurred in Fe, followed by Fe-Cr and last a relatively no damage is SS 316L implant. The subcutaneously implanted material suffered higher damage than the intramuscularly implanted material. The greatest corrosion rate occurred in Fe implant. The corrosion rate of Fe-Cr lower than Fe implant (P<0.05) at the first time of implantation. The weight loss of Fe not significantly differ (P>0.05) as the weight loss of Fe-Cr at the first time of implantation, but its lower than the weight lose of Fe-Cr implant (P<0.05) at the last time of implantation. SS 316L implant not showed the corrosion rate and the weight loss. As a conclusion , Fe and Fe-Cr implants were potentially as implant materials that can be degraded and therefore could be use for medical applications.
Keyword: mice, iron based metal implant, biomaterial, biodegradable

Judul: Studi Biokompatibilitas Besi (Fe) Sebagai Material Penyusun Implan Logam Terserap Tubuh Pada Mencit (Mus Musculus).
Abstrak: Penelitian ini bertujuan untuk mendapatkan informasi mengenai biokompatibilitas besi sebagai material penyusun implan logam terserap tubuh melalui pengamatan klinis dan histologis. Informasi ini didapat melalui pemeriksaan respon profil darah perifer, kadar ion besi dan magnesium dalam plasma darah, penilaian radiodensitas pada pencitraan radiografi dan respon jaringan secara histopatologis. Sebanyak 48 ekor ekor mencit strain ddy jantan, dewasa, berusia 8 minggu dibagi ke dalam 4 kelompok. Kelompok tersebut adalah kelompok kontrol, kelompok implan kawat besi, kelompok implan magnesium batang dan kelompok implan kawat medis. Kelompok kontrol diberi perlakuan sham dan kelompok implan diberikan implan yang disisipkan di antara tulang femur dengan otot biceps femoris. Pemeriksaan respon darah dilakukan dengan pemeriksaan darah rutin, sementara kadar ion besi dan magnesium plasma diperiksa dengan menggunakan metode Atomic Absorption Spectroscopy (AAS) yang dilakukan pada hari pengamatan ke-0 sebelum implantasi, hari ke-1, 10 dan 30 setelah implantasi. Pencitraan radiografi dilakukan pada hari ke-1, 7, 14 dan 30 setelah implantasi. Radiodensitas implan selanjutnya dianalisa dengan menggunakan piranti lunak ImageJ®. Studi histopatologi dilakukan pada jaringan otot dan tulang lokasi implan yang dipanen pada hari ke-1 dan 30 setelah impantasi. Hasil analisa pada pemeriksaan jumlah sel darah merah, kadar hemoglobin, nilai hematokrit, jumlah sel darah putih total dan diferensiasi sel darah putih menunjukkan perbedaan yang tidak nyata. Kadar ion besi pada kelompok implan besi menunjukkan peningkatan yang signifikan di dalam plasma darah. Radiodensitas implan dan daerah sekitarnya mengalami perubahan sesuai dengan respon tubuh yang terjadi. Studi histopatologi menunjukkan adanya reaksi inflamasi akut pada hari pengamatan ke-1 untuk semua kelompok, baik kontrol maupun yang diberikan implan. Sedangkan pada hari ke-30 setelah implantasi, reaksi benda asing berupa kapsul fibrosa ditemukan mengelilingi lokasi implan pada kelompok implan kawat besi dan kawat medis. Sebagai kesimpulan, implan besi menyebabkan peningkatan kadar ion besi di dalam darah dan reaksi inflamasi yang terbatas, dan tidak ditemukan adanya efek toksik dari produk degradasi maupun dari implan besi itu sendiri.
Keyword: besi, implan terserap tubuh, biokompatibilitas, in vivo, reaksi benda asing

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite