Uric Acid Level Has a J-Shaped Association with Arterial Stiffness in Korean Postmenopausal Women

Background: Uric acid has been reported to function both as an oxidant or antioxidant depending on the context. A previous study in the Korean population reported a positive linear association between serum uric acid level and arterial stiffness in men, but little is known about how serum uric acid level is related to the risk of increased arterial stiffness in Korean postmenopausal women. Methods: We performed a cross-sectional study of 293 subjects who participated in a health examination program run by the health promotion center of Gangnam Severance Hospital between October 2007 and July 2010. High brachial-ankle pulse wave velocity was defined as a brachial-ankle pulse wave velocity of more than 1,450 cm/s. The odds ratios (ORs) for high brachial-ankle pulse wave velocity were calculated using multivariate logistic regression analysis across uric acid quartiles after adjusting for other indicators of cardiovascular risk. Results: The 293 postmenopausal women were divided into quartiles according to uric acid level. The mean brachial-ankle pulse wave velocity values of each quartile were as follows: Q1, 1,474 cm/s; Q2, 1,375 cm/s; Q3, 1,422 cm/s; Q4, 1,528 cm/s. The second quartile was designated as the control group based on mean brachial-ankle pulse wave velocity value. Multivariate adjusted ORs (95% confidence intervals) for brachial-ankle pulse wave velocity across the uric acid quartiles were 2.642 (Q1, 1.095-6.3373), 1.00, 4.305 (Q3, 1.798-10.307), and 4.375 (Q4, 1.923-9.949), after adjusting for confounding variables. Conclusion: Serum uric acid level has a J-shaped association with arterial stiffness in Korean postmenopausal women.ope

고백적 글쓰기의 표현방식 연구 : 해방공간의 소설을 중심으로

학위논문(석사)--서울대학교 대학원 :국어교육과,1999.Maste

멀티모드 Handset에 적합한 재구성이 가능한 선형 EDGE 증폭기

학위논문(석사) --서울대학교 대학원 :전기. 컴퓨터공학부,2008.2.Maste

Seasonal variation of the Sound scattering Layer (SSL) around Yellow Sea Bottom Cold Water (YABCW) in Korea region, 2011-2012

The Yellow Sea Bottom Cold Water (YSBCW), defined as having a salinity of 32.0&#8211;33.0 psu and a temperature < 10°C, has a major influence on the oceanic environment of the Yellow Sea and is one of the main water masses in this sea in summer. The presence of the YSBCW has important effects on zooplankton, nekton, and other biological organisms in the Yellow Sea. For understanding the sound scattering layer (SSL) in the YSBCW region, this study presents results obtained from acoustic measurements taken in the YSBCW region in Korea region, in spring and summer of 2011 and 2012. For each survey, 13&#8211;27 hours of 200 kHz acoustic data were continuously collected at a stationary station. The acoustic volume scattering strength data (Sv) were analyzed with temperature profile data. In spring 2011/2012, the SSL migrated from surface layer at night to near the bottom at day time, due to the entire water column was well mixed with cool water. Then the descending and ascending speeds of the SSL were 0.7 m min-1 and 0.6 m min-1, respectively. In summer seasons, the SSL migrated from below thermocline at night to near the bottom at day time, due to the water column was divided in to two layer along strong thermocline. The SSL started to descend at a speed of 1.3 m min-1. Very high speed in summer 2011 was due to changes of the water column after typhoon (called Muifa). In addition to water temperature, suspended materials may be some influence on vertical migration of the SSL. It is concluded that the SSL patterns at the YSBCW site may be greatly influenced by water column changes during spring and summer season.1

In situ side-aspect target strength of Japanese anchovy (Engraulis japonicus) in northwestern Pacific Ocean

Acoustic side-aspect target strength (TS) of living Japanese anchovy (Engraulis japonicus) was measured at 120 kHz during in situ experiments. The data were collected by lowering and horizontally projecting the split-beam transducer into the anchovy school. For analysis and interpretation of the side-aspect TS data, acoustic theoretical model, based on the fish morphology, and dorsal-aspect TS data were used. Total length of the anchovy ranged from 6.6 to 12.8 cm (mean length 9.3 cm). The side-aspect TS distributed between -40 and -55 dB, has an obvious length dependency. The mean side-aspect TS of the anchovy was -47.8 dB, and the TS was about 2 dB higher than mean TS generated from dorsal-aspect measurements. With reference to maximum TS, the results of the side-aspect TS were distributed within the range of the theoretical and dorsal-aspect TS. Apparently these tendency indicates that side-aspect TS measured from the study is useful data. These in situ measurements of side-aspect TS can be applied to improve acoustic detection and estimates of the anchovy, and is necessary to measure with a various frequency and length for making enhance data.22Nkc

Side-aspect acoustic target strength of giant jellyfish, N. nomurai

본 연구에서는 노무라입깃해파리의 생태 및 자원량 평가를 위한 소나 혹은 수평 방향의 음향 시스템 활용에서 기본 자료로 활용될 해파리의 측면 음향 반사강도(이하 측면 TS) 특성을 알아보고자 하였다. 이를 위하여 살아있는 해파리를 대상으로 해상 실험을 실시하였다. 대상 생물인 노무라입깃해파리에 대한 측면 TS 실험은 2009년 8 ～ 9월에 한국해양연구원 통영 해양생물자원연구&#8228;보존 센터(이하 통영 MRC)에서 실시되었다. 주파수 200 kHz에 대한 개체별 노무라입깃해파리의 평균 측면 TS의 범위는 -61 ～-40 dB의 범위에서 변화를 가지고 있었다. 측정된 측면 TS 결과를 해파리의 우산의 직경(bell diameter, D, cm)와 음파의 파장()의 비율(D/)에 대한 회귀 곡선으로 나타내면 다음과 같다(TS200kHz = 24.6 log(D/λ) - 93.6). 해파리의 크기에 대한 측면 TS 결과의 종속성을 확인하였고, 일정 크기 이상의 해파리의 경우에는 단일 개체임에도 불구하고 상대적으로 높은 측면 TS 분포를 보여준다. 결과적으로 해파리의 측면에서 음향을 탐지 가능성을 확인하였고, 이 결과는 향후 소나와 같은 수평 음향 시스템을 통한 해파리의 탐지를 위한 기본 조사 자료로 활용될 수 있을 것이다.2

Acoustic target strength for single Jellyfish, Cyanea nozakii, and its symbiotic fish

Acoustic surveys are used to evaluate the numerical abundance and biomass of many pelagic fish species and some crustacean zooplankton. As jellyfish are important consumers of zooplankton and ichthyoplankton, and may detrimentally affect fish populations, knowledge of jellyfish distribution and abundance is therefore of economic as well as ecological importance. In recently, the acoustic detection has been used to monitor distribution and biomass of jellyfish, and simultaneously target strength (TS) measurements are conducted for the several jellyfish species. In this study, acoustic measurements of ex situ TS were made on live jellyfish, Cyanea nozakii, and its symbiotic fish, using 38, 120, 200, and 420 kHz split-beam transducers. The jellyfish were tethered using very thin line penetrated to their umbrella, and an underwater video camera was used to continuously monitor behavior. Data for 19 individual Jellyfish ranging from young to adult sizes (bell diameter, D = 19 - 46 cm) and data for symbiotic fishes (total length = 3.3 - 8.0 cm) were analyzed. In C. nozakii, the mean TS values were -50.45 dB at 38 kHz, -54.94 dB at 120 kHz, -54.12 dB at 200 kHz, and -54.74 dB at 420 kHz. Overall, the mean TS with bell diameter in air was higher at 38 kHz than at 120, 200, and 420 kHz. Least-squares regression fits of TS vs. log(D) were: TS38kHz = 19.98&#8901;log10(D) - 80.57 (r=0.70),TS120kHz = 21.41&#8901;log10(D) - 87.22 (r=0.74), TS200kHz = 19.84&#8901;log10(D) - 84.03 (r=0.69), and TS420kHz = 20.13&#8901;log10(D) - 85.09 (r=0.76). In the case of symbiotic fish, the mean TS values were -50.45 dB, at 38 kHz, -54.94 dB at 120 kHz, -54.12 dB at 200 kHz, and -54.74 dB at 420 kHz. The difference between 38 kHz and higher frequencies was between 3.7 dB and 4.5 dB. These ex situ measurements of TS can be applied to improve acoustic detection and estimates of the jellyfish, Cyanea nozakii.1

Distribution and Abundance of Japanese Anchovy Engraulis japonicus and Other Fishes in Asan Bay, Korea, estimated Hydroacoustic Survey

The distribution and abundance of coastal fish species in Asan Bay, Korea, were estimated from hydroacoustic survey and net catches. Acoustic data were collected with 38 and 200 kHz from July to October of 2012, and converted to the nautical area scattering coefficient (NASC, m2/mile2 ) for 0.25n⋅mile along ten transects. Japanese anchovy Engraulis japonicus was the dominant specie in the net catches. The virtual echogram technique was used to distinguish E. japonicus from other species based on the differences in the mean volume backscattering strength ( ΔMVBS ) at 38 and 200 kHz. Engraulis japonicus and other fishes are mainly distributed in the center channel and outer part of Asan Bay. E. japonicus tends to move from inner to outer Asan Bay in summer and fall. From NASC data, the target strength and length-weight function of E. japonicus and other fishes were used to estimate the E. japonicus stock at 24.1-93.3 tons, and other fish at 40.6-88.4 tons from July to October 2012. The estimated anchovy biomass compared well with the cumulative catch weight from stow net catches. The hydroacoustic method offers an approach to understanding spatial/temporal structure and estimating the biomass of fish aggregations in coastal areas.22Nkc

Measurements of Sound Speed and Density Contrasts of the Moon Jellyfish (Aurelia aurita s.l.) for Hydroacoustic Model

Physical properties such as sound speed contrast (h) and density contrast (g) of the interested target are key parameters to understand acoustic characteristics by using theoretical scattering models. The density and sound speed of moon jellyfish (common jellyfish, Aurelia aurita s.l.) were measured. Sound speed contrast (h) was measured from travel time difference (time-of-flight method) of an acoustic signal in a water tank for APOP studies (Acoustic Properties Of zooplankton). Density contrast (g) was measured by the displacement volume and wet weight (dual-density method). The sound speed remained almost constant as the moon jellyfish increased in bell length. The mean values±standard deviation of h and g were 1.0005±0.0012 and 0.9808±0.0195), respectively. These results will provide important input for use in theoretical scattering models for estimating the acoustic target strength of jellyfish.33scopuskc