목적: 연성콘택트렌즈를 장기간 착용한 경험자와 무경험자에서 굴절교정 수술 후 안압변화에 차이가 있는지 알아 보고자 하였다. 방법: 라섹(LASEK, Laser assisted sub-epithelial keratomileusis)수술을 시행 받은 95명 189안의 환자를 대상으로 의무기록을 후향적으로 분석하였다. 수술 전 연성콘택트렌즈 착용자와 미착용자 두 그룹으로 분류하였고 술 후1개월이 지난 뒤 조건 별 안압변화량을 비교하였다. 결과: 연성콘택트렌즈 착용자와 미착용자에 대한 라섹수술 후 안압의 변화는 12.95±2.598mmHg, 14.20±4.038mmHg에서 10.13±2.817mmHg, 11.47±3.549mmHg(p=0.04)으로 두 그룹 모두 안압이 2.822±2.805mmHg(p=0.000), 2.739±4.203(p=0.000) 떨어졌지만 착용자, 미착용자의 두 그룹 간에 수술 후 안압의 의미 있는 차이는 없었다. 수술 전 평균구면대응치, 각막두께, 레이저 각막절삭량과 수술 후 안압 변화는 연성콘택트렌즈 착용자 중 경도근시와 고도근시인 그룹(p

We have made semi-analytical studies to investigate the configurations of caustics and the probability distribution of the flux factor K for the binary microlensing including external shears. A parametric equation of critical curve is derived in a 4th order complex polynomial. We present the topological dependencies of the caustics for selected gamma parameters (0, 0.3, 0.6, 1.3, 2.0, and 2.5) and convergence terms (0., 0.4, 0.8, 1.2, 1.6, and 2.0). For the purpose of analyzing the efficiency of High Amplification Event (HAE) on each caustics, we examine the probability distribution of the flux factor by a Monte Carlo method. Changing the separation of the binary system from 0.8 to 1.3 (in normalied unit), we examine the probability distribution of the K-values in various gamma parameters. The relationship between gamma parameters, seperations and their probabilties of the flux factor K have been studied. Our results show that the relatively higher K values (K>1.5) are increased as increasing the separation of the binary system. We therfore conclude that, in the N-body microlensing, the probabilities of higher HAEs are inversely proportional to the star density as well. We also point out that the present research might be used as a preliminary step toward investigating heavy N-body microlensing simulations.

The removal of nitrogen compounds from a wastewater is essential and it is often accomplished by biological process. An aerobic nitrate-removing bacterium was isolated from a municipal sewage treatment plant and soil. On the basis of its morphological, cultural and physiological characteristics and 16S rRNA sequencing data, this strain was identified as Pseudomonas fluorescens, and named as P. fluorescens K4. The optimal conditions of the initial pH and temperature of media for its growth were 7.0~8.0 and 30℃, respectively. P. fluorescens K4 was able to remove 99.9% of nitrate after 24 h in a culture. The strain could grow with a nitrate concentration up to 800 mg/l and was able to remove 99.9% of nitrate after 104 h of incubation. The optimal electron donor was sodium citrate for a nitrate removal. The strain K4 showed a capability of a complete nitrate removal when the initial C/N ratio was 1.0. An effect of the initial seed concentration was observed for a cell of 10% (v/v) for a nitrate removal. Especially P. fluorescens K4 could completely remove 200 mg/l ammonium for 3 days.

Proline is known as an osmotrotectant to enhance tolerance against both salt and dehydration stresses. A P5CS (δ1 -pyrroline-5-carboxylate synthetase) plays a major role in regulation of synthesis of proline. An overexpression of the mothbean P5CS gene in transgenic tobacco plant increased the levels of proline and osmotolerance. In an attempt to look for the possibility to use content of proline as well as a level of P5CS gene expression as molecular markers for salt tolerance, the amounts of proline and transcript levels of P5CS were measured as functions of either concentration of NaCl or length of treatment period among different species of zoysiagrass. Hybridzoysia showed the highest level of proline (329~mu~textrmg /g.f.w.) among five different species of zoysiagrass at 250 mM NaCl in 24 hours. The level of P5CS transcript was also the highest in the hybridzoysia at 250 mM NaCl in 24 hours. The transcriptions of P5CS gene were induced at the rates of 1.2, 1.2, 1.8, and 1.8, upon treatment of 250 mM NaCl in Z. japonica, Z. matrella, Z. sinica and hybridzoysia respectively. Based on a correlation between the level of P5CS transcript and the proline content among different species of zoysiagrass, a comparative structural analysis of the gene for P5CS from either Z. sinica or hybridzoysia may lead to an understanding of mechanism for salt tolerance shown differently among zoysiagrasses.