• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4671-4677
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• 2023

For the first time Pb, Ni, and Cu nanocomposites were synthesized by versatile solution combustion synthesis using Aloevera extract as a reducing agent, to study the potential applications in X-ray/gamma, neutron, and Bremsstrahlung shielding. The synthesized Lead-Nickel-Copper (LNC) nanocomposites were characterized by PXRD, SEM, UV-VIS, and FTIR for the confirmation of successful synthesis. PXRD analysis confirmed the formation of multiphase LNC NCs and the Scherrer equation and the W-H plot gave the average crystal sizes of 19 nm and 17 nm. Surface morphology using SEM and EDX confirmed the presence of LNC NCs. Strong absorption peaks were analyzed by UV visible spectroscopy and the direct energy gap is found to be 3.083 eV. Functional groups present in the LNC NCs were analyzed by FTIR spectroscopy. X-ray/gamma radiation shielding properties were measured using NaI(Tl) detector coupled with MCA. It is found to be very close to Pb. Neutron shielding parameters were compared with traditional shielding materials and found LNC NCs are better than lead and concrete. Secondary radiation shielding known as Bremsstrahlung shielding characteristics also studied and found that LNC NCs are best in secondary radiation shielding. Hence LNC NCs find shielding applications in ionizing radiation such as X-ray/gamma and neutron radiation.

• Dementia and Neurocognitive Disorders
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• v.23 no.3
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• pp.136-145
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• 2024

Background and Purpose: We developed a new digital cognitive assessment called Seoul Cognitive Status Test (SCST), formerly called Inbrain Cognitive Screening Test. The purpose of this study was to validate the clinical utility of the SCST by comparing its scores of those with subjective cognitive decline (SCD), amnestic mild cognitive impairment (aMCI), and dementia diagnosed by the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD-K). Methods: All participants (n=296) who completed the CERAD-K, SCST, and Instrumental Activities of Daily Living tests were included in this study. Total score, cognitive domain scores, and subtest scores of the SCST were compared among the 3 groups (SCD, aMCI, and dementia). Additionally, correlations between SCST and CERAD-K subtests were examined. Results: Cognitive domain scores and total score of the SCST showed significant differences among the three groups, with scores being the highest in the order of SCD, aMCI, and dementia (p<0.001). Most subtests of the SCST also showed higher scores in the order of SCD, aMCI, and dementia (p<0.001). However, SCD and aMCI groups showed no significant differences in scores of the Phonemic Word Fluency Test (p=0.083) or Korean Trail Making Test-Elderly version Part A (p=0.434). Additionally, there was no significant difference in the score of Place Recognition (p=0.274) of the Word-Place Association Test between aMCI and dementia groups. Conclusions: In conclusion, differences in total score, cognitive domain scores, and subtest scores of the SCST among the 3 groups of participants diagnosed using CERAD-K confirm the clinical utility of the SCST for cognitive assessment.

• Journal of Gastric Cancer
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• v.20 no.2
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• pp.152-164
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• 2020

Purpose: To compare long-term disease-free survival (DFS) between patients receiving tegafur/gimeracil/oteracil (S-1) or capecitabine plus oxaliplatin (CAPOX) adjuvant chemotherapy (AC) for gastric cancer (GC). Materials and Methods: This retrospective multicenter observational study enrolled 983 patients who underwent curative gastrectomy with consecutive AC with S-1 or CAPOX for stage II or III GC at 27 hospitals in Korea between February 2012 and December 2013. We conducted propensity score matching to reduce selection bias. Long-term oncologic outcomes, including DFS rate over 5 years (over-5yr DFS), were analyzed postoperatively. Results: The median and longest follow-up period were 59.0 and 87.6 months, respectively. DFS rate did not differ between patients who received S-1 and CAPOX for pathologic stage II (P=0.677) and stage III (P=0.899) GC. Moreover, hazard ratio (HR) for recurrence did not differ significantly between S-1 and CAPOX (reference) in stage II (HR, 1.846; 95% confidence interval [CI], 0.693-4.919; P=0.220) and stage III (HR, 0.942; 95% CI, 0.664-1.337; P=0.738) GC. After adjustment for significance in multivariate analysis, pT (4 vs. 1) (HR, 11.667; 95% CI, 1.595-85.351; P=0.016), pN stage (0 vs. 3) (HR, 2.788; 95% CI, 1.502-5.174; P=0.001), and completion of planned chemotherapy (HR, 2.213; 95% CI, 1.618-3.028; P<0.001) were determined as independent prognostic factors for DFS. Conclusions: S-1 and CAPOX AC regimens did not show significant difference in over-5yr DFS after curative gastrectomy in patients with stage II or III GC. The pT, pN stage, and completion of planned chemotherapy were prognostic factors for GC recurrence.

• Journal of Environmental Impact Assessment
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• v.21 no.3
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• pp.483-501
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• 2012

The purpose of this study was to apply a multi-metric model of Lentic Ecosystem Health Assessments(LEHA) for environmental impact assessments of Cheongpyung Reservoir during 2005 - 2006 and assessed the ecological model values. The ecosystem model of LEHA was composed of eleven metrics such as biological parameters($B_p$), physical parameters($P_p$), and chemical parameters($C_p$), and determined the rank of ecological health by the criteria. The variables of $B_p$ were metrics of % sensitive species($M_2$, NMS) and insectivore species($M_5$, % $I_n$), which decrease as the water quality degradates, and these metric values were low as 1.5% and 32.4%, respectively. In contrast, the proportions of tolerant species and omnivore species as the other $B_p$ parameters were 43% and 62%, respectively, which indicate a degradation and disturbance of the ecosystem. Riparian vegetation coverage($M_9$, % $V_c$) as a variable of $P_p$, were higher in the 2nd than 1st survey, and decreased toward the dam site from the headwaters. This was due to a habitat simplification(modifications) by frequent bottom dredging of sand and rocks. The variables of $C_p$ were two metrics of specific conductivity($M_{10}$, $C_I$) as an indicator of ionic contents(cations and anions) and the Trophic State Index(TSI) based on chlorophyll-a($M_{11}$, $TSI_{CHL}$) as an indicator of trophic state. These metric values of $C_p$ had high temporal variations, but low spatial variations on the main axis of the reservoir along with the ecological health of a good condition. The environmental impact assessments using the LEHA multi-metric model indicated that the model values of LEHA averaged 30.7 in 1st survey(fair - poor condition) vs. 28 in 2nd survey(poor condition), indicating a temporal variation of the ecological health. The model values of LEHA showed a minimum(28) in the lacustrine zone(S5) and ranged from 29 to 30 in the other locations sampled, indicating a low longitudinal variation. Overall, environmental impact assessments, based on LEHA model, suggest that chemical water quality conditions were in good, but biological conditions were disturbed due to habitat modifications by frequent dredgings in the system.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.93-104
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• 2005

Objective : Because the cause and etiology of chronic headache are not yet fully explained, the treatment of this symptom is not simple. In order to study the effectiveness of East-West pain treatment on chronic headache, we evaluated its effect of pain alleviation and quality of life improvement on chronic headache patients who were treated with nerve block and acupuncture, and only acupuncture for eight weeks. Methods : 92 clinical experiment participants were gathered and through a questionnaire patients who experienced headache for more than 4 hours a day and more than 15 days per month were qualified as chronic headache patients. The qualified patients were classified into two groups, nerve block and acupuncture group(EW group, n=49) and acupuncture group(E group, n=43). Treatment was applied 2 times a weeks for 8 weeks. The acupoints, GV20, HN23, ST8, HN46, TE17, GB20, LI20O, LI11, LI14, ST36, and LR3 were stimulated for 20 minutes. The effects of two groups were analyzed using VAS scores and BPI(Brief Pain Inventory).

• Korean journal of applied entomology
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• v.47 no.2
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• pp.155-162
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• 2008

The Welsh onion beet armyworm, Spodoptera exigua (Hubner), has attacked Welsh onion and is now the most important pest of Welsh onion in southwestern Korea. The beet armyworm has a wide host range, occurring as a serious pest of vegetable and fields. The relatively high abundance of beet armyworm has stimulated frequent application of insecticides to foliage. Insecticide resistance is a major problem in management of this insect. Accordingly, pesticide application for the control of beet armyworm was tried in both the open field and in laboratory, using 4 synthetic compounds such as metaflumizone and chlorfenapyr, indoxacarb, flufenoxuron, emamectin benzoate. In the laboratory, each developmental stages from eggs, larva to pupa was tested against 4 insecticides. Against the eggs of welsh onion beet armyworm, there was no significantly different with each other. These tested chemicals no killing effect to eggs. However, the population of 1st larva hatched from eggs were reduced because they eaten the egg shell with residual insecticides. The tested insecticides were taken very high mortalities to 1st to 3rd larva of Welsh onion beet armyworm. Otherwise, there were decreased the death rate from 4th to 6th larva. On the other hand, their value of control effects were relatively good against Welsh onion beet armyworms in the field between 87.2 and 90.5% on 10 days after insecticide application.

• Progress in Medical Physics
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• v.13 no.3
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• pp.120-128
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• 2002

To investigate differences between the metabolic ratios of normal controls and brain tumors such as astrocytomas and glioblastoma multiforme (GM) by proton MR spectroscopy (MRS) at 37 high field system. Using 3T MRI/MRS system, localized water-suppressed single-voxel technique in patients with brain tumors was employed to evaluate spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cr) and lactate. On the basis of Cr, these peak areas were quantificated as a relative ratio. The variation of metabolites measurements of the designated region in 10 normal volunteers was less than 10%. Normal ranges of NAA/Cr and Cho/Cr ratios were 1.67$\pm$018 and 1.16$\pm$0.15, respectively. NAA/Cr ratio of all tumor tissues was significantly lower than that of the normal tissues (P=0.005). Cho/Cr ratio of glioblastoma multiforme was significantly higher than that of astrocytomas (P=0.001). Lactate was observed in all tumor cases. The present study demonstrated that the neuronal degradation or loss was observed in all tumor tissues. Higher grade of brain tumors was correlated with higher Cho/Cr ratio, indicating a significant dependence of Cho levels on malignancy of gliomas. This results suggest that clinical proton MR spectroscopy could be useful to predict tumor malignancy.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.44-52
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• 2010

The objective of this in vitro study was to detect and monitor demineralization and remineralization of primary teeth according to restorative materials using quantitative light-induced fluorescence (QLF). A single bur hole was drilled on the each sound forty eight primary anterior teeth, and the specimens were divided into three groups. The cavity was restored with $Filtek^{TM}$ Z250(Group 1), F2000(Group 2), $Ketac^{TM}$ N100(Group 3) following the manufacturer's instructions. The teeth were subjected to the demineralizing buffer for 3 days, and then subjected to a remineralizing buffer for 14 days. The change of mineral loss(${\Delta}Q$) according to the stages was evaluated by QLF and the following results were obtained: 1. When demineralization was done, ${\Delta}Q$ was increased as follows. : Group 1 ($-110.79\;{\pm}\;27.77$) < Group 2 ($-104.84\;{\pm}\;28.95$) < Group 3 ($-90.16\;{\pm}\;21.87$) : Resistance to demineralization was statistically significant in Group 3. 2. There was a statistically significant increase in ${\Delta}Q$ of all groups since 1st day of remineralization 3. The rate of remineralization, ${\Delta}$(${\Delta}Q$)/day, showed significant high value in each group on the 1st day then decreased rapidly. 4. There was no statistically significant difference in the degree of remineralization among restorative materials.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.502-508
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• 1998

Proinflammatory cytokines such as tumor necrosis factor-$\alpha$(TNF-$\alpha$) have been implicated in myocardial and organ dysfunction associated with postperfusion syndrome. We tested the hypothesis that cytokine productions are depressed by preoperative cortiosteroid injection for cardiopulmonary bypass(CPB) and the postoperative courses will be better than without steriod pretreated cases. Cardiac surgery was performed in randomized blind fashion for 20 patients from June 1996 to September 1996. In the steroid group(n=10), corticosteroid(dexamethasone 1 mg/kg) was injected 1 hour before anesthetic induction, but in the control group(n=10), nothing was injected. Each of groups were sampled 11 times as scheduled for TNF-$\alpha$ bioassays. We have checked EKG, cardiac enzymes(CPK, LDH with isoenzyme), WBC count preoperative day, one day and three days after operation. Viatal signs were continuously monitored for three postoperaive days. In the postoperative period three patients in the control group had elevated body temperature and four patients had hypotension that required considerable intravenous fluid administration. But steroid injected patients showed normal body temperture and acceptable blood pressures without supportive treatment. CPK enzymes rose in control group higher than steroid group at postoperative 1st and 3rd day(CPK; 1122$\pm$465 vs 567$\pm$271, 864$\pm$42 vs 325$\pm$87), and CPK-MB enzymes rose in control group higher than steroid group at postoperative 1st day(106.4$\pm$115.1 vs 29.5$\pm$22.4)(P=0.02). Arterial tumor necrosis factor-$\alpha$ rose during cardiopulmonary bypass, peaking at 5 minutes before the end of aortic cross clamping(ACC-5min) in steroid group(11.9$\pm$4.7 pg/ml), and 5 minutes before the end of cardiopulmonary bypass(CPB-5min) in control group(22.3$\pm$6.8 pg/ml). The steroid pretreated patients had a shorter period of time in respirator suport time, ICU stay day, hospital admission day. We conclude that corticosteroid suppress cytokine production during and after cardiopulmonary bypass, and may improve the postoperative course through inhibition of reperfusion injury such as myocardial stunning and hemodynamic instability.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.526-532
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• 2017

Development, survival, and reproduction of brown planthopper (BPH) Nilaparvata lugens $St{\aa}l$ (Hemiptera: Delphacidae), were studied in laboratory at $25{\pm}2^{\circ}C$, $65{\pm}5%$ RH and a 16L : 8D hours photoperiodism on five rice cultivars of: Dongjin 1ho, Chungchungbyeo, Jangseongbyeo, Chinnongbyeo and Jungmo 1045. BPH nymphs successfully survived on all rice cultivars, although survival rate was lowest on Jangseongbyeo (36.0%). Developmental time of immature stages ranged from $11.7{\pm}0.59d$ on Jungmo 1045 to $12.8{\pm}0.59d$ on Chinnongbyeo. Reproductive period and female longevity were longest on Dongjin 1ho, Chinnongbyeo and Jungmo 1045 while highest fecundity of N. lugens being observed on these three rice cultivars. Highest and lowest net reproductive rates were calculated on rice cultivars, Jungmo 1045 and Jangseongbyeo, respectively. Mean generation time was the longest on rice cultivar Dongjin 1ho. Respective descending order of intrinsic rates of population increase were on Jungmo 1045, Chinnongbyeo, Dongjin 1ho, Chungchungbyeo and Jangseongbyeo. These population parameters showed that N. lugens can successfully survive and reproduce on Chinnongbyeo and Jungmo 1045.