Judul: Maskulinisasi Ikan Cupang (Betta splendens) Melalui Perendaman Embrio dalam Ekstrak Purwoceng (Pimpinella alpina)
Abstrak: This study aimed to know the effect of extract of P. alpina for masculinization of Betta splendens. This research used the Completely Randomized Design with 3 treatments that were distinguished by doses of extract of P. alpina, those are 10, 20, and 30 μL/L, and 0 μL/L as control. The treatments are given to 35 embryos by immersion in extract of Pimpinella alpina when eye spots phase or about 28th hour after fertilization. The immersion process was done for 8 hours. The result showed that 20 μL/L dose of P. alpina’s extract produced male fish percentage 62,66%, it’s higher than control (45,91%), and hatching rate was 85,71%. At the higher dose (30 μL/L), male fish population and hatching rate went down with each value 39,72% and 68,57%.
Keyword: 

Judul: Masculinization of Betta Fish (Betta splendens) throught larval Immersion Method Using Forest Honey
Abstrak: Betta fish is freshwater fish with characteristic of being happy to compete. The beauty of the color, shape and pattern of fish is special attraction so that it has high selling value, especially in males. Reversal sex through masculinization techniques, is able to produce higher study ratio. This study aims to test effectiveness of immersion betta fish (B. splendens) larval stage in honey solution and study its effect on fish survival. This study used complete randomized design (RAL) method with one factor in the form of immersion time. There were five lengths of immersion as treatment, 0 hours (Control), 24 hours (P1), 28 hours (P2), 32 hours (P3) and 36 hours (P4) with 3 tests each. Larvae used are aged 3 days after hatching. The results showed that length of soaking had a significant (P<0.05) on survival rates in all treatments. The percentage of male sex observed in the K treatment was 21,66±4,81%, P1 was 50,85±2,92%, P2 was 50,58±4,59%, P3 was 52,46±3,90% and P4 was 0%. The effective soaking time treatment is for 24 hours. The effect of natural honey on the masculinization of betta fish was effective in P1 treatment of 50,85±2,92% and survival rate of 94,95±1,37%., Ikan cupang adalah ikan air tawar dengan karakteristik senang berlaga dengan sesama jenisnya. Keindahan warna, bentuk dan corak ikan menjadi daya tarik tersendiri sehingga mempunyai nilai jual tinggi terutama pada jantan. Seks reversal melalui teknik maskulinisasi, mampu menghasilkan rasio pejantan menjadi lebih tinggi. Penelitian ini bertujuan menguji efektivitas waktu perendaman ikan cupang (B. splendens) stadia larva didalam larutan madu serta mempelajari pengaruhnya terhadap kelangsungan hidup ikan. Penelitian ini menggunakan metode rancangan acak lengkap (RAL) dengan satu faktor berupa lama waktu perendaman. Terdapat lima lama perendaman sebagai perlakuan yaitu 0 jam (K), 24 jam (P1), 28 jam (P2), 32 jam (P3), 36 jam (P4) dengan masing-masing 3 ulangan. Larva yang digunakan berumur 3 hari setelah menetas. Hasil penelitian menunjukan bahwa lama perendaman berpengaruh nyata (P<0,05) terhadap tingkat kelangsungan hidup pada semua perlakuan. Persentase kelamin jantan yang teramati pada perlakuan K sebesar 21,66±4,81%, P1 sebesar 50,85±2,92%, P2 sebesar 50,58±4,59%, P3 sebesar 52,46±3,90% dan P4 sebesar 0%. Perlakuan waktu perendaman yang efektif yaitu selama 24 jam. Pengaruh madu pada maskulinisasi ikan cupang efektif pada perlakuan P1 sebesar 50,85±2,92% dan tingkat kelangsungan hidup sebesar 94,95±1,37%.
Keyword: daya tarik, efektivitas, seks reversal, waktu perendaman

Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
Keyword: