Judul: Respon cendawan tanah terhadap herbisida glifosat
Abstrak: Glifosat (N-(fosfonometil)glisina) merupakan herbisida post emergent, berspektrum luas dan non selektif. Walaupun diaplikasikan secara post emergent, molekul glifosat mencapai tanah juga dan secara kuat akan diikat oleh partikel-partikel tanah. Residu glifosat yang terdapat di dalam tanah akan menyebabkan dampak terhadap keadaan tanah termasuk mikroorganisme tanah. Penelitian ini bertujuan untuk memperoleh cendawan tanah yang mampu tumbuh cepat pada media dengan glifosat konsentrasi tinggi dan mengamati pertumbuhannya pada berbagai konsentrasi glifosat. Sebanyak 72 isolat berhasil diisolasi dari tanah Biotrop (Bogor) dan Sukabumi yang telah disemprot glifosat 1445 gram dalam 404 liter larutan per hektar tanah (disemprot pada konsentrasi 3,577 mg/ml atau konsentrasi lapang) menggunakan media kecambah kacang hijau. Lima isolat dari 72 isolat mampu tumbuh cepat (lebih dari setengah diameter cawan petri selama 5 hari) pada glifosat 8 x konsentrasi lapang. Kelima isolat tersebut diidentifikasi sebagai Trichoderma koningii B5.1, Trichoderma sp. B9.5, anggota Mucorales isolat B21.1, Aspergillus flavus S7.2, dan Trichoderma harzianum S10.1. Pertumbuhan semua cendawan terpilih kecuali Trichoderma harzianum S10.1 meningkat seiring peningkatan konsentrasi glifosat sampai 2 x konsentrasi lapang, bahkan sampai 4 x konsentrasi lapang pada anggota Mucorales isolat B21.1. Pertumbuhan Trichoderma harzianum S10.1 menurun seiring peningkatan konsentrasi glifosat. Pertumbuhan semua cendawan terpilih terhambat pada glifosat 8 x konsentrasi lapang.
Keyword: Glifosat, cendawan, pertumbuhan

Judul: Deteksi penguraian herbisida glifosat oleh bakteri tanah
Abstrak: Glifosat (N-(phosphonomethyl) glycine) merupakan herbisida berspektrum luas, post-emergence, dan nonselektif. Glifosat di tanah secara kuat diikat oleh partikel tanah dan sebagian akan mengalar penguraian secara kimia dan hayati. Penelitian ini bertujuan mendapatkan isolat-isolat bakteri tanah yang diharapkan mampu menguraikan glifosat, diawali dengan isolasi bakteri dan penapisannya serta mengamati hasil penguraian glifosat oleh isolat bakteri terpilih menggunakan metode Kromatografi Lapis Tipis. Sampel tanah diambil dari Sukabumi dan Biotrop, Bogor yang gulmanya telah disemprot 1445 g monoamonium glifosat dalam 404 liter larutan per hektar tanah (larutan tersebut mengandung glifosat 2,67 mg/ml). Penapisan isolat dilakukan dengan konsentrasi glifosat bertingkat, yaitu 10,16 mg/ml, 20,32 mg/ml, dan 40,64 mg/ml. Tiga dari 19 isolat bakteri yang diperoleh toleran terhadap ketiga konsentrasi glifosat tersebut, dua isolat bakteri diantaranya diidentifikasi sebagai Leuconostoc sp. galur S30.1 dan Pseudomonas pseudoflava B25.1. Hasil Kromatografi Lapis Tipis menunjukkan bahwa kedua isolat bakteri terpilih dan Pseudomonas aeruginosa, sebagai kontrol positif, yang ditumbuhkan dalam kaldu nutrien mengandung glifosat 0,71 mg/ml dengan masa inkubasi enam hari tidak terdapat hasil penguraian glifosat. Hasil yang sama ditunjukkan juga pada P. pseudoflava B25.1 yang ditumbuhkan pada media yang sama dengan masa inkubasi 23 hari.
Keyword: 

Judul: The Effects of Variance of Interest rate to Variance of Annuity Future Values
Abstrak: Time value of money is a concept that refers to the difference of the value of money due to time difference. The value of money for present time would not be the same as the value of money in the future. The value of money for present time is called as Present Value (PV) of the money and the value of money for future time is called Future Value (FV) of the money. Determination the value of money, for present and future time, depends on the time and rate of return. The value of money is determined by several factors such as inflation, fluctuation of interest rates, and government policy in securities and taxation. Due to fluctuation of the value of money we need a FV formulation, it is useful for knowing whether an investment can be profitable or not, and this information is useful also in budget analysis. Annuity is defined as a series of payments made for a specific period. The payment, fixed or varied, can be made at the beginning or at the end of the period. Annuity paid at the beginning of the period is called annuity-due and annuity paid at the end of the period is called immediate annuity-certain. The accumulated value of the annuity after few years later is called as a final value or a future value. Burnecki et al. (2003) have discussed about the FV of a fixed-rate annuity in which payments are made according to the arithmetic or geometric series. They have also examined FV for annuities in which payments are made according to arithmetic or geometric series with random rates of interest. This paper examines FV for annuity-due in which payments are made according to arithmetic or geometric series with interest rates as a random variable, which is normal distribution ,  . Future value formula is expressed in recursive form. FV for annuity-due which payments are made according to the arithmetic or geometric series with random rates of interest is calculated by theoretical way and simulation way. The random rates of interest is denoted as k k i  i  , where k i an independent random variable; i is a constant and k  is a random variable which has normal distribution ,  . By using the determined parameters, a sequence of random rates of interest are generated for theoretical calculation. Meanwhile for the simulation, the random rates of interest is generated 1000 times for the simulation. The generated data give mean value, variance, and standard deviation. Moreover, error of mean value, variance, and standard deviation from the theoretical and simulation results are calculated. Error calculation uses Symmetric Mean Absolute Percentage Error (SMAPE). The smaller the value of SMAPE is the more accurate the simulation. The interest rate variances are varied from 0.000036 to 0.0001 to study the relationship between variance of rates of interest and variance of future value. The theoretical and simulation results show that when the variance of random rates of interest increases, then the variance of FV increases linearly. FV of the annuity-due in
Keyword: