Judul: Peranan estrogen dalam pengendalian proses-proses reproduksi
Abstrak: Penulisan ini bertujuan untuk mempelajari sejauh mana peranan estrogen dalam pengendalian proses-proses reproduksi. Selain itu juga dipelajari mengenai sifat-sifat dasar dari estrogen yang mencakup struktur kimia dan biosintesa, fungsi fisiologik serta mekanisme kerja dari estrogen secara umum. Estrogen dalam mempengaruhi aktivitas organ lain akan berkaitan dengan reseptor protein. Kemudian kompleks protein estrogen ini yang akan menuju ke inti sel dan menyebabkan perubahan metablisme yang spesifik. Mekanisme kerja estrogen sangat erat berhubungan dengan kerja hormon lain. Dengan LH, estrogen mempunyai mekanisme kerja umpan balik positip sedang dengan FSH estrogen mempunyai mekanisme kerja umpan balik negatip. Beberapa daya kerja estrogen yang telah diketahui adalah merangsang pertumbuhan dan kontraksi uterus, merangsang perubahan epitel vagina, merangsang pertumbuhan dan aktivitas muskuler pada tuba falopii, merangsang pertumbuhan sistim saluran kelenjar ambing, merangsang pengenduran symphisis pubis, merangsang pertumbuhan bentuk hewan betina, menyebabkan kelakuan berahi. ...
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Judul: Interaksi estrogen dan progesteron dalam pengendalian proses reproduksi ternak sapi
Abstrak: Tujuan penulisan ini adalah untuk mempelajari sejauh mana interaksi estrogen dan progesteron dalam pengendalian proses-proses reproduksi, dan juga mempelajari sifat-sifat dasar estrogen dan progesteron yang mencakup struktur kimia dan biosintesa, fungsi fisiologik serta mekanisme kerja dari kedua hormon tersebut secara umum. Tulisan ini merupakan suatu studi pustaka. Estrogen dan progesteron merupakan hormon reproduksi primer dan termasuk kelompok steroid dengan inti cyclopentanoperhydropenantrene yang masing-masing terdiri dari 18 atom karbon (C) dan 21 atom C. Kelenjar hypophysa merupakan kelenjar pengatur, sedang yang berperan utama adalah corpus luteum sebagai penghasil progesteron, placenta sebagai penghasil estrogen dan progesteron, dan folikel de Graaf sebagai penghasil estrogen. Progesteron sangat esensial dalam mempertahankan kebuntingan bersama-sama dengan estrogen o- varium dan gonadotropin serta prolaktin yang disekresi oleh hypophysa anterior. ...
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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