Judul: Adaptation and tolerance of rice genotypes to phosphorus deficiency in paddy soil
Abstrak: Javanese Tree Frog (R. margaritifer 1837) is an endemic frog of Java Island. Population of this species is threatened due to human activity and the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Therefor sterilization of Bd is needed as the first effort to protect of R. margaritifer outside their natural habitats. The research aims to assess: 1) frog behaviour after and before sterilization treatment; 2) best temperature for sterilization by heat treatment for Bd on frogs vitality; and 3) behaviour of frog’s adaptation in terrarium after sterilization. Research were conducted in Indonesian Safari Park I Cisarua, West Java includes specimen’s collection in Curug Jaksa and Rumah Dua. Sterilization were carried out using two methods, i.e (I) aquarium heater with hot steam and (II) aquarium heater with dry heat temperature. A total of 12 frogs were sterilized with 3 different temperature treatment for each heater. Ad libitum sampling methods was used in the observation of the behaviour of adaptation during captivity. In general the condition of frog captured for experiment and moved to temporary terrarium were good, in which most of them were active. All of frogs were resting before sterilization. The most effective sterilization temperature for R. margaritifer is 37˚C for 4 hours. Terrarium provided by Indonesian Safari Park were not sufficient for its movement as shown with the injured in snout part of frogs. There is only a small differences of temperature between natural habitats and terrarium which is not affecting R. margaritifer activity. Frogs were active in the evening from 18.00–23.00. During the daytime, frogs use different kind of a substrate to rest such as terrarium glass, hanjuang leafes, rocks, and fluorescent bulb. Overall, hanjuang leafes and terrarium glass was the most widely used by frogs to 23%. During 30 day period of captivity, in view from the number of feed consumption and unstable changes of body weight, frogs haven’t been able to adapt properly. Behaviour of R. margaritifer before and after sterilization suggesting that sterilization had not caused negative effect to R. margaritifer behaviour. The survival of frogs in captivity was 100% since no mortality were observed after sterilization.
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Judul: Studi Adaptasi dan Perilaku Katak Bertanduk (Megophrys montana Kuhl & van Hasselt 1822) di Penangkaran Taman Safari Indonesia I Cisarua Jawa Barat
Abstrak: Indonesian safari park (TSI) as conservation institution in Indonesian is planning to carried out captive breeding prog as part of ex-situ amphibian conservation. One of the species selected is Megophrys montana. The pathogen fungi Batrachochytrium dendrobatidis (Bd) has been found in frogs of West Java, therefor effort to captive breeding frogs from the wild must include prevention of Bd infection by sterilization. The aims of this research is to look frog condition during captivity period after collection until pre sterilization, effectiveness sterilization of the pathogen fungi Bd to the survival ability and adaptation in captive breeding of M. montana in captivity after sterilization. Research is carried out in TSI on July-September 2012. Data collected using ad libitum sampling method. Frogs were sterilizied using Itraconazole (Sporanox 10 mg / m l ) 0.01% on 0.6% salinity applied on the skins for 5 minutes / days for 11 days. Number of frogs collected are six (two female and four male). All frogs were put in pairs on separates aquarium. However, on the 6th day one frogs were missing presumably by cannibalism. Therefor the remaining of five frogs are put in separate aquarium on the next day. All frogs in captivity were observed with normal behaviour as before sterilization. Most of M. montana individual showed quiet behavior during setrilization (87%). The function of terrarium is only sufficient for maintaining the lives of individual frogs. The size of terrarium at TSI was less than one meter which is not enough for the movement of M. montana. There is also differences of humidity condition between its natural habitat and terrarium, therefor there is a need to add rain chamber for artificial rain. The condition of all frogs in captivity during adaptation was normal and healthy. On average M. montana start feeding on the 4th day to the 6th day with a daily increases amount of cricket. Nearly all fros showed an increase body mass except one male individual which shown 0.5 g on 2nd week. However the same frog showed an increase of body mass. The low result of feed convertion rate indicates that the efficiency of feed were use for body weight growth. M. montana number 5 had a lowest feed convertion rate and the highest growth of body weight compared others. M. montana were active at 06.00 pm until 05.00 am. On morning and afternoon, all frogs slept under rock, wood and coconut shell. Generally all frogs will move by 07.00 pm until 10.00 pm. Four frogs spent time mostly under a rock and wood, where as male frog number 3 mostly used litters during the resting period. Frogs start calling on the 7th day in terrarium. Calls were emitted all day long and mostly heard on 02.00 pm until 05.00 pm
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Judul: Aproksimasi Fungsi Sinus dan Kosinus sebagai Kombinasi Linear dari Fungsi Eksponensial
Abstrak: Salah satu gagasan yang menarik dalam matematika adalah aproksimasi suatu fungsi oleh fungsi lain. Sebagai contoh, fungsi polinom dapat diaproksimasi menggunakan deret Taylor atau fungsi persamaan diferensial dapat diaproksimasi menggunakan deret Fourier. Adapun fungsi yang dapat mengaproksimasi fungsi lain salah satunya adalah fungsi eksponensial. Kemungkinan mengaproksimasi fungsi dengan kombinasi linear dari fungsi eksponensial dari bentuk eˣ, e²ˣ, ... dianggap sebagai perkembangan sejajar dengan gagasan Deret Taylor yang mengaproksimasi fungsi dengan kombinasi linear dari segi fungsi kuadrat. Fungsi sin x dan cos x digunakan sebagai target untuk menilai seberapa baik aproksimasi yang dilakukan oleh fungsi yang diberikan. Aproksimasi fungsi sinus dan kosinus menggunakan hampiran Taylor lebih akurat dibandingkan dengan aproksimasi menggunakan fungsi eksponensial.
Keyword: Aprosimaksi eksponensial, aproksimasi fungsi, aprosimaksi Taylor, fungsi eksponensial