목 적: 국내 시판 실리콘하이드로젤 콘택트렌즈의 산소투과도와 함수율 등을 측정하고 국내 제품과 해외 수입제품, 각 회사별로 구분하여 그 결과를 분석하였다. 방 법: 국내에서 시판되어 유통되고 있는 7개의 회사의 25종 실리콘하이드로젤 콘택트렌즈를 대상으로 함수율, 산소전달도, 산소투과도를 측정하였다. 결 과: 실리콘하이드로젤 콘택트렌즈의 함수율은 33~48%의 범위로 측정되었으며, 국내 제품과 해외 수입제품이 비슷한 범위의 함수율을 나타내었다. 그러나 산소전달도(Dk/t)의 경우, 국내 제조제품은 평 균 8.46±1.14×10-9(cm/mlO2)/(sec×ml×mmHg), 해외 수입제품은 평균 83.66±4.63×10-9(cm×mlO2)/ (sec×ml×mmHg)로 측정되어 그 차이가 매우 크게 나타났다. 결 론: 실리콘 하이드로젤 콘택트렌즈는 재질에 따라 주요 물리적 특징인 산소전달도가 크게 차이가 있 는 상황이기에 판매사의 정확한 정보제공이 필요하며, 렌즈 선택 시 주의가 필요할 것으로 판단된다.

We present the results of BV time-series photometry of the globular cluster NGC 288. Ob- servations were carried out to search for variable stars using the Korea Microlensing Telescope Network (KMTNet) 1.6-m telescopes and a 4k pre-science CCD camera during a test observation from August to December, 2014. We found a new SX Phe star and confirmed twelve previously known variable stars in NGC 288. For the semi-regular variable star V1, we newly determined a period of 37.3 days from light curves spanning 137 days. The light-curve solution of the eclipsing binary V10 indicates that the system is probably a detached system. The pulsation properties of nine SX Phe stars were examined by applying multiple frequency analysis to their light curves. We derived a new Period-Luminosity (P-L) relation, hMV i = −2.476(±0.300) logP − 0.354(±0.385), from six SX Phe stars showing the fundamental mode. Additionally, the period ratios of three SX Phe stars that probably have a double-radial mode were investigated; PFO/PF = 0.779 for V5, PTO/PFO = 0.685 for V9, PSO/PFO = 0.811 for V11. This paper is the first contribution in a series assessing the detections and properties of variable stars in six southern globular clusters with the KMTNet system.

Microalgae are of significant importance for future biotechnological applications. Many microalgae banks or laboratories attempt to maintain various microalgae for further research purposes. Cryopreservation has been preferred to reduce a labor-intensive and costly routine sub-culturing. Cryopreservation can also diminish the genetic drift risk. However, cryopreservation as a long term storage of microalgae method are still in developing progress because it cannot be generalized for all microalgae. Microalgae types, cryoprotectant agents (CPAs) types, freezing and thawing methods are the most important factors that should be considered for cryopreservation. In this short review the basic principles and the current advanced of microalgae cryopreservation methods are discussed with a suggested starting parameters for microalgae cryopreservation.

Well-dispersed Ag3VO4 nanoparticles @polyacrylonitrile (PAN) nanofibers were synthesized by an easily controlled, template-free method as a photo-catalyst for the degradation of methylene blue. Their structural, optical, and photocatalytic properties have been studied by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy equipped with rapid energy dispersive analysis of X-ray, photoluminescence, and ultraviolet–visible spectroscopy. The characterization procedures revealed that the obtained material is PAN nanofibers decorated by Ag3VO4 nanoparticles. Photocatalytic degradation of methylene blue investigated in an aqueous solution under irradiation showed 99% degradation of the dye within 75 min. Finally, the antibacterial performance of Ag3VO4 nanoparticles @PAN composite nanofibers was experimentally verified by the destruction of Escherichia coli. These results suggest that the developed inexpensive and functional nanomaterials can serve as a non-precious catalyst for environmental applications.

Obesity is a risk factor for various diseases, including cardiovascular disease, diabetes, renal disease, hypertension, cancer, and neural disease. Adipose tissue in animals is important for the mobilization of lipids, milk production, deposition of fat in different depots, and muscle and meat production. Understanding the genetic and physiological causes of metabolic disease is a priority in biomedical genome research. In this study, we examined several variables in mice fed a high-fat diet, including serum composition, body weight, total calorie intake, and differentially expressed genes. Body weight and blood glucose levels were not significantly different between animals fed high-fat and normal diets. However, high-fat diet groups showed reduced calorie and food intakes. Levels of sodium, ionized calcium, glucose, hematocrit, hemoglobin, pH, PCO2, PO2, TCO2+, HCO3+, base excess, and SO2 in the blood were not significantly different between mice fed high-fat and normal diets. Serum potassium concentration, however, was lower in mice a high-fat diet. Differentially expressed genes were also compared between the two groups. The purpose of this study was to discover new genes as a result of annealing control primer (ACP) PCR using 20 random primers. Five down regulated genes were identified and three of others were up-regulated by high-fat diet. Known genes were excluded from this result. In addition, the relationships among candidate genes and high-fat diet should be investigated according to potassium concentration in the blood. In conclusion, mice fed normal and high-fat diets showed no significant difference in body weight, whereas high-fat diet led to changesin blood composition and differential expression of several genes. These findings may provide a better understanding of the mechanisms underlying the association between obesity and metabolic diseases.

Active Galactic Nuclei (AGN) with bright radio jets oer the opportunity to study the structure of and physical conditions in relativistic out ows. For such studies, multi-frequency polarimetric very long baseline interferometric (VLBI) observations are important as they directly probe particle densities, magnetic eld geometries, and several other parameters. We present results from rst-epoch data obtained by the Korean VLBI Network (KVN) within the frame of the Plasma Physics of Active Galactic Nuclei (PAGaN) project. We observed seven radio-bright nearby AGN at frequencies of 22, 43, 86, and 129 GHz in dual polarization mode. Our observations constrain apparent brightness temperatures of jet components and radio cores in our sample to > 108:01 K and > 109:86 K, respectively. Degrees of linear polarization mL are relatively low overall: less than 10%. This indicates suppression of polarization by strong turbulence in the jets. We found an exceptionally high degree of polarization in a jet component of BL Lac at 43 GHz, with mL  40%. Assuming a transverse shock front propagating downstream along the jet, the shock front being almost parallel to the line of sight can explain the high degree of polarization.

Bi0.5Na0.5TiO3 (BNT) based ceramics are considered potential lead-free alternatives for Pb(Zr,Ti)O3(PZT) based ceramics in various applications such as sensors, actuators and transducers. However, BNT-based ceramics have lower electromechanical performance as compared with PZT based ceramics. Therefore, in this work, lead-free bulk 0.99[(Bi0.5Na0.5)0.935Ba0.065](1-x)LaxTiO3-0.01SrZO3 (BNBTLax-SZ, with x = 0, 0.01, 0.02) ceramics were synthesized by a conventional solid state reaction The crystal structure, dielectric response, degree of diffuseness and electric-field-induced strain properties were investigated as a function of different La concentrations. All samples were crystallized into a single phase perovskite structure. The temperature dependent dielectric response of La-modified BNBT-SZ ceramics showed lower dielectric response and improved field-induced strain response. The field induced strain increased from 0.17% for pure BNBT-SZ to 0.38 % for 1 mol.% La-modified BNBT-SZ ceramics at an applied electric field of 6 kV/mm. These results show that Lamodified BNBT-SZ ceramic system is expected to be a new candidate material for lead-free electronic devices.

Recently, climate change has been increasingly reported to be associated with vector-borne diseases including West Nile Virus, avian poxvirus, bluetongue virus. These diseases, which are of medical and veterinary importance, are known to affect the health status of wildlife. In this sense, it is vital to understand the distribution of mosquitoes and biting midges as the disease-vectors in the habitat of wildlife. In order to do this, nocturnal insects were collected using CDC Mini Night Traps (cat. no. 2836BXQ, BioQuip, CA, USA) in the coniferous and deciduous forest near the ponds in National Institute of Ecology (NIE) on the weekdays from June to September. As a result, 920 mosquitoes belonging to 13 species of 7 genus and 5,129 biting midges belonging to 8 species of Culicoides were collected in total. For mosquitoes, Aedes vexans nipponii and Culex orientalis were the predominant species consisting about two thirds of all the mosquitoes. For biting midges, Culicoides arakawae was the prevalent species present and 97.3% of this kind appeared to have preference to feed on birds. The number of mosquitoes collected remained relatively constant as opposed to the number of biting midges which showed the tendency to fluctuate - the second or third week of each month had the highest number of Culicoides spp. Forest ecology had more diverse distribution of species than livestock farms and reflected the abundance of birds in NIE. In addition, further evaluation of the effect of environment, such as climatic factors, on the ecology of these disease vectors would be required.

Hydroxyapatite (HA), which is an important calcium phosphate mineral, has been applied in orthopedics, dentistry, and many other fields depending upon its morphology. HA can be synthesized with different morphologies through controlling the synthesis method and several parameters. Here, we synthesize various morphologies of HA using two simple methods: hydrothermal combustion and solution combustion. The phase purity of the synthesized HA is confirmed using X-ray diffractometry. It demonstrates that pure phased hydroxyapatite can be synthesized using both methods. The morphology of the synthesized powder is examined using scanning electron microscopy. The effects of pH and temperature on the final powder are also investigated. At 140 oC, using the hydrothermal method, nano-micro HA rods with a hexagonal crystal structure can be synthesized, whereas using solution combustion method at 600 oC, a dense cubic morphology can be synthesized, which exhibits monoclinic crystal structures.

The effects of Nb doping on the crystal structure, microstructure, and dielectric ferroelectric and piezoelectric properties of (Bi0.5Na0.5)0.935Ba0.065Ti(1-x)NbxO3-0.01SrZrO3 (BNBTNb-SZ, with x = 0, 0.01 and 0.02) ceramics have been investigated. X-ray diffraction patterns revealed that all ceramics have a pure perovskite structure with tetragonal symmetry. The grain size of the ceramics slightly decreased and a change in grain morphology from square to spherical shape was observed in the Nb-doped samples. The maximum dielectric constant temperature (Tm) increases with increasing amount of Nb; however, ferroelectric-relaxor transition temperature (TF-R) and maximum dielectric constant (εm) values decrease gradually. Nb addition disrupted the polarization hysteresis loops of the BNBT-SZ ceramics by leading a reduction in the remnant polarization coercive field and piezoelectric constant.

New lead-free piezoelectric ceramics 0.96[{Bi0.5 (Na0.84 K0.16)0.5}1-xLax(Ti1-y Nby)O3]-0.04SrTiO3 (BNKT-ST-LN, where x = y = 0.00 ≤ (x = y) ≤ 0.015) were synthesized using the conventional solid-state reaction method. Their crystal structure, microstructure, and electrical properties were investigated as a function of the La and Nb (LN) content. The X-ray diffraction patterns revealed the formation of a single-phase perovskite structure for all the LN-modified BNKT-ST ceramics in this study. The temperature dependence of the dielectric curves showed that the maximum dielectric constant temperature (Tm) shifted towards lower temperatures and the curves became more diffuse with an increasing LN content. At the optimum composition (LN 0.005), a maximum value of remnant polarization (33 C/cm2) with a relatively low coercive field (22 kV/cm) and high piezoelectric constant (215 pC/N) was observed. These results indicate that the LN co-modified BNKT-ST ceramic system is a promising candidate for lead-free piezoelectric materials.