Judul: Penelitian penentuan derajat toksisitas tanaman ciplukan pada hewan percobaan katak dan mencit
Abstrak: Tujuan penelitian adalah menentukan derajat toksisitas tanaman Ciplukan (Physalis minima Linn.) pada hewan percobaan katak dan mencit dengan menentukan LD 50 nya. Berat katak yang dipakai dalam percobaan ini adalah 30-70 gram, sedangkan berat mencit adalah 20-30 gram. Dalam per cobaan ini infus Ciplukan dengan konsentrasi 20% disuntikkan secara subcutan pada katak dan intra-peritoneal pada mencit. Penentuan nilai LD 50 menggunakan Metodą Trevan dan Metoda Karber. Penghitungan menurut cara Trevan menggunakan analisis statistik dengan model persamaan garis sigmoid yaitu y = a + bln x. Pengambilan contoh dilakukan secara acak. Dengan cara Karber, LD 50 dapat langsung dibuat dengan per samaan LD 50 = ab/c. Nilai a adalah dosis terkecil yang dapat menyebabkan kematian tertinggi sekelompok hewan percobaan. Nilai b adalah jumlah hasil kali antara beda dosis dengan interval rata-rata yang mati dan c adalah jum lah populasi dalam sekelompok dosis.
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Judul: Toksisitas Ekstrak Ciplukan (Physalis angulata) Berdasarkan Uji Letalitas Larva Udang
Abstrak: Physalis angulata known as ciplukan in Indonesia is widely used as herbal medicinal plant. Studies on this plant revealed its potency as antidiabetic, antioxidant, antimicrobial, and antiasthma, but the toxicity is not reported yet. This study aimed to determine the toxicity of leaf extracts from ciplukan by using brine shrimp lethality test (BSLT). Phytochemical test of crude ethanolic extract indicated the presence of alkaloids, flavonoids, and steroids. Ethanol crude extract was extracted by liquid-liquid extraction and gave 2 extracts, namely n-hexane and ethyl acetate extracts. BSLT results showed that all the extracts were toxic. n- Hexane extract was the most toxic extract with value of LC50 3 ppm, indicating its potency as anticancer.
Keyword: Bogor Agricultural University (IPB), Physalis angulata, ciplukan, brine shrimp lethality test

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