Authors:Jin-Hong Lee, Jong-Myoung Lim, and Ki-Hyun Kim
Instrumental neutron activation analysis was conducted on PM 10 samples collected in Daejeon city, Korea during September 2001 to May 2002. Our measurement data were analyzed to explain the behavior of particle-bound elemental components in relationship with Asian Dust (AD) events. The results of our analysis indicated that the major crustal elements (e.g., Al, Ca, Fe, K, Mg, and Ti) showed strong enrichment (about 3 to 9 times higher concentration levels) during the AD period accompanied by the increase in the PM 10 levels (e.g., by about 3 times). However, the concentrations of anthropogenically derived elements (such as As, Br, Sb, Se and Zn) exhibited moderate change during the AD period. Hence, the computation of enrichment factor (EF) indicated that the magnitude of EF values during the AD period was even smaller in the case of toxic metals than its non-AD counterpart. The existence of relatively low EF values during the AD period can be attributed to the excessive input of crustal components. The overall results of our study suggest that both absolute and relative elemental composition of aerosol particles can be altered significantly by the AD events.
Authors:Yong Chung, Sun Kim, Gwang Sun, Jong Lim, Jong Moon, Kye Lee, and Hwa Yoo
The aim of the research is to find out better medicinal stuff for thyroid cancer patients who are required to have a low level
iodine diet. Iodine contents in 12 kinds of oriental herbal medicinal prescriptions, which are frequently used for thyroid
cancer patients, are determined using instrumental neutron activation analysis. The biological certified reference material
was used for analytical quality control. The relative errors and standard deviations for the iodine analysis were less than
2.88 and 18.5%, respectively. The level of iodine contents for four medicinal samples detected was in the range of about 3–210 mg/kg,
the concentrations of eight samples were estimated from the detection limit under the given analytical conditions. In addition,
the informative concentrations of 17 essential elements with special functions such as Al, As, Ba, Br, Ca, Cl, Cr, Fe, K,
Mg, Mn, Na, Rb, Sr, Ti, V, and Zn in the samples were also determined together with their detection limits for data inter-comparison.
The relative errors and standard deviations for these elements were in the range of 0.1–18.0%, and 2–20%, respectively.
Authors:Yong Chung, Sun Kim, Gwang Sun, Jong Lim, Jong Moon, Kye Lee, Young Kim, Jong Choi, and Ju Lee
The analysis of mineral contents in space foods is needed to obtain an information on a comprehensive elemental composition
as well as the investigation on the effects of human nutrition and health based on the dietary intake of mineral elements.
Recently, six items of new Korean space foods (KSFs) such as kimchi, bibimbap, bulgogi, a ramen, a mulberry beverage and a
fruit punch which was developed by the KAERI, and the contents of more than 15 elements in the samples were examined by using
instrumental neutron activation analysis (INAA). Five biological certified reference materials, NIST SRM were used for analytical
quality control. The results were compared with those of common Korean foods reported, and these results will be applied toward
the identification of irradiated foods.
Authors:Yong-Sam Chung, Sun-Ha Kim, Jong-Hwa Moon, Hark-Rho Kim, Jong-Myoung Lim, and Jin-Hong Lee
For air pollution monitoring, about 1300 airborne particulate matter samples were collected by using a low volume air sampler
and a polycarbonate filter at two sampling sites in an urban region, Daejeon, the middle of Korea from 2003 to 2006. Mass
concentrations of the black carbon were measured using a smoke stain reflectometer. The concentrations of 24 elements in the
collected samples were analyzed by using instrumental neutron activation analysis, and its temporal trends and enrichment
factors were investigated under different environmental conditions. Analytical control was carried out by using certified
Authors:Yong-Sam Chung, Sun-Ha Kim, Jong-Hwa Moon, Young-Jin Kim, Jong-Myoung Lim, and Jin-Hong Lee
For the identification of air pollution sources, about 500 airborne particulate matter (PM2.5and PM10) samples were collected by using a Gent air sampler and a polycarbonate filter in an urban region in the middle of Korea
from 2000 to 2003. The concentrations of 25 elements in the samples were measured by using instrumental neutron activation
analysis (INAA). Receptor modeling was performed on the air monitoring data by using the positive matrix factorization (PMF2)
method. According to this analysis, the existence of 6 to 10PMF factors, such as metal-alloy, oil combustion, diesel exhaust,
coal combustion, gasoline exhaust, incinerator, Cu-smelter, biomass burning, sea-salt, and soil dust were identified.
Authors:Yong-Sam Chung, Sun-Ha Kim, Moon Jong-Hwa, Young-Jin Kim, Jong-Myoung Lim, and Jin-Hong Lee
As part of an air pollution monitoring study, airborne particulate matter (PM2/PM10-2) samples were collected from 2000 to 2003 at two sampling sites in an urban region, Daejeon, the middle of Korea. Mass concentrations
of both fine and coarse fractions and that of the black carbon in the fine particles were measured using the Gent stacked
filter unit sampler and the smoke stain reflectometer, respectively. In the collected samples the concentrations of 24 elements
were analyzed using instrumental neutron activation analysis. Monitored data were investigated for their temporal trends under
different environmental conditions and their seasonal correlation patterns. Crustal enrichment factors were also estimated
to establish the contribution between anthropogenic and crustal origin. Patterns for airborne particle matter (APM) and elemental
concentrations, seasonal variation of some marker elements were investigated. The results can be applied for the investigation
of further air pollution sources and for the evaluation of air quality.
Authors:Yeon-Jin Kim, Jae A. Lim, Ji Yoon Lee, Sohee Oh, Sung Nyun Kim, Dai Jin Kim, Jong Eun Ha, Jun Soo Kwon, and Jung-Seok Choi
Background and aims
Internet gaming disorder (IGD) is characterized by a loss of control and a preoccupation with Internet games leading to repetitive behavior. We aimed to compare the baseline neuropsychological profiles in IGD, alcohol use disorder (AUD), and obsessive–compulsive disorder (OCD) in the spectrum of impulsivity and compulsivity.
A total of 225 subjects (IGD, N = 86; AUD, N = 39; OCD, N = 23; healthy controls, N = 77) were administered traditional neuropsychological tests including Korean version of the Stroop Color–Word test and computerized neuropsychological tests, including the stop signal test (SST) and the intra–extra dimensional set shift test (IED).
Within the domain of impulsivity, the IGD and OCD groups made significantly more direction errors in SST (p = .003, p = .001) and showed significantly delayed reaction times in the color–word reading condition of the Stroop test (p = .049, p = .001). The OCD group showed the slowest reading time in the color–word condition among the four groups. Within the domain of compulsivity, IGD patients showed the worst performance in IED total trials measuring attentional set shifting ability among the groups.
Both the IGD and OCD groups shared impairment in inhibitory control functions as well as cognitive inflexibility. Neurocognitive dysfunction in IGD is linked to feature of impulsivity and compulsivity of behavioral addiction rather than impulse dyscontrol by itself.