Judul: Pemberian Kalsium Nano Ca3(Po4)2 Terhadap Efektivitas Penyerapan Kalsium Tulang Hewan Model Tikus Putih Rattus Novergicus
Abstrak: Kalsium nano adalah kalsium dengan ukuran partikel 1-100x10-9m, yang diharapkan dapat diserap lebih efektif ke dalam peredaran darah, selanjutnya dideposisi di tulang. Penelitian ini bertujuan untuk mengatahui efek pemberian kalsium nano pada ransum terhadap serapan kalsium dalam tulang di hewan model tikus putih (Rattus norvegicus) strain Sprague dawley pada umur yang berbeda. Sejumlah 20 ekor tikus dipelihara selama 5 minggu dalam kandang individu dan dibagi kedalam empat kombinasi perlakuan. Rancangan percobaan menggunakan faktorial 2 X 2, faktor A merupakan umur (2 dan 5 bulan), dan faktor B adalah ransum dengan ukuran partikel kalsium biasa (kontrol) atau nano. Empat ekor tikus muda diambil sampel tulangnya pada saat pemeliharaan 3 dan 4 minggu. Peubah yang diukur adalah konsumsi bahan kering (BK), konsumsi kalsium (Ca), kadar Ca feses, serapan Ca, kadar Ca serum, kadar Ca tulang tibia dan pertambahan bobot badan harian (PBBH). Pemberian kalsium nano dalam ransum tidak menunjukkan adanya interaksi antara kedua faktor utama. Tikus umur 2 bulan memiliki PBBH lebih tinggi (P<0.01). Kalsium dengan ukuran nano nyata mempengaruhi konsumsi (P<0.05), serapan kalsium (P<0.01). Secara kualitatif tulang bagian luar terkristalisasi lebih baik, hasil analisis menggunakan Scanning Electron Microscopy (SEM).
Keyword: 

Judul: Penyerapan dan Deposisi Kalsium di Tulang Tibia Pada Hewan Model Rattus novergicus Yang Diberi Purified Diet Mengandung Nano Kalsium
Abstrak: Penelitian ini bertujuan untuk mengevaluasi penggunaan nano kalsium dalam purified diet terhadap penyerapan dan deposisi kalsium pada pertumbuhan tikus (Rattus novergicus) galur Sprague dawley sebagai hewan model. Sebanyak 12 tikus berumur 2 bulan dengan bobot 200-250 g, ditempatkan dalam kandang individu dan dibagi menjadi dua perlakuan, yaitu diet kontrol (diet tanpa nano kalsium) dan diet nano kalsium. Data dianalisis dengan membandingkan dua rataan menggunakan T-test berpasangan. Parameter yang diukur yaitu konsumsi bahan kering (BK) dan konsumsi kalsium, kalsium feses, serapan kalsium, kalsium plasma, deposisi kalsium serta phosphor dan magnesium tulang tibia, morfologi tulang (bobot, panjang dan diameter) serta pertambahan bobot badan harian (PBBH). Hasil menunjukkan bahwa konsumsi dan serapan kalsium serta phosphor dan magnesium tulang tibia pada perlakuan nano signifikan lebih tinggi (P<0.05) dibandingkan perlakuan kontrol. Tidak ada pengaruh penambahan nano kalsium terhadap konsumsi BK, kalsium feses, kalsium plasma, kalsium tulang tibia dan morfologi tulang. Tikus yang diberi purified diet mengandung nano kalsium menghasilkan serapan kalsium sampai 99%.
Keyword: Bogor Agricultural University, Institut Pertanian Bogor, IPB, Calcium digestibility, nano calcium, purified diet, Sprague dawley

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