• Journal of Environmental Impact Assessment
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• v.29 no.4
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• pp.252-271
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• 2020

In this study, we investigated physical and chemical properties such as grain size, heavy metal pollution, magnetic properties, and their environmental impacts of road dusts (RD) collected from 14 sampling points in Daebul industrial Complex. Heavy metal concentrations in RD were in the order of Fe>Zn>Cu>Pb>Cr>Ni>As>Cd>Hg, and this pollution pattern was related to major industries and traffic activities in this area. The results of the correlation analysis between heavy metal elements and particle size in RD showed that Fe and all of analyzed heavy metals had a significant correlation with each other and metal concentrations had a significantly negative correlation (p<0.05). However, due to the input of large metal particles some heavy metal concentrations in the particle fraction of >1000 ㎛ were highest. Pollution load per unit area of this fraction was the highest among the grain size fractions. Cr, Ni, Cu, Zn, Cd, Pb levels in RD decreased and the levels of Cr, Ni, Cu, Zn, Cd, and Pb were reduced to 85 (As) -22 (Ni)% of the whole after removal of MFs fraction from RD. The mean heavy metal levels in the study area did not exceed the soil contamination guide value of Korea, indicating that heavy metal levels in RD were not a concern. However, at some sampling points, Zn concentrations were exceeded the soil contamination guide value for the 3rd areas of Korea and this result indicated that further studies of the impact of RD on the surrounding environment through re-suspension or non-point pollution, and of effective management methods are required.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.6
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• pp.17-27
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• 2014

Wild boars are one of the major wild life animals of which the number has increased a lot because there has been any predator and/or competitor in the Korean ecosystem. The increase of their number was a cause damaging crops in farm lands during the growing season in South Korea. This study was done to recognize the spatial pattern of farm lands damaged by wild boars. Totally 2,342 farms were known damaged by wild boars in 2012, and used to statistically analyze the perspectives of the farm land damages by wild boars in ArcMap v. 9.3. Damages by wild boars frequently happened in the western part of Gyeongnam Province including Jinju city, Tongyoung city and Namhae county. Most farm lands damaged were located nearby large mountains in this area. It might cause the number of wild boars increased in this area, which could finally stimulate the increase of farm land damaged by the species. Farm land damages by wild boars were also coincident with the preference of wild boars on their food. They preferred crops (e.g., sweet potato and corn) in uplands and rice paddies and orchards. The reason of their preference on rice, upland crops and fruits was related to the efficiency of their getting much more energy in a unit area. Another reason for the species to come into a rice paddy would be that they enjoy mud bath in there for scraping off parasites such as ticks and lice. Wild boars were seemed much overcrowded during the period from July to October when most of crops and fruits get ripen. About three-quarters of total farm land damages happened in this period. This analysis also said that 1,915 fields (81.8% of total targets) appeared within the 100-meter buffer from boundaries of mountain areas. This meant that wild boars were more sensitive to the anthropogenic land uses than we expected. They seemed to conservatively try their feeding activities in farm lands with paying attention to the human activity.

• Tuberculosis and Respiratory Diseases
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• v.71 no.5
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• pp.335-340
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• 2011

Background: Community-acquired pneumonia (CAP) is an important cause of morbidity and mortality throughout the world in all age groups. Viral causes of CAP are less well characterized than bacterial causes. We analyzed the characteristics of hospitalized patients with CAP who had a viral pathogen detected by multiplex polymerase chain reaction (PCR). Methods: Multiplex real-time PCR was performed for respiratory viruses in samples collected from 520 adults who developed CAP at Chungnam National University Hospital. Clinical, laboratory, and radiological features at presentation as well as other epidemiological data were analyzed. Results: Of 520 patients with CAP, a viral pathogen was detected in 60 (11.5%), and influenza A was the most common. The virus detection rate in patients with CAP was highest in November. Two or more pathogens were detected in 13 (21.7%) patients. Seven patients had severe disease and were administered in the intensive care unit. Most patients (49/60, 81.7%) had comorbidities. However, nine (15%) patients had no comorbidities, and their age was <60 years. The ground glass opacity pattern was the most common radiological feature. Seven (11.7%) patients died from CAP. Conclusion: Viral pathogens are commonly detected in patients with CAP, and a respiratory virus may be associated with the severity and outcome of pneumonia. Careful attention should be paid to the viral etiology in adult patients with CAP.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.639-645
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• 2009

The objective of this research was to introduce the TPI approach for interpreting land-forms of mountain forests in South Korea. We develop an objective procedure to decide the scale factor as a basic analytical unit in land-form classification of rugged mountain areas using TPI. In order to determine the scale factor associated with the pattern of slope profiles, the gradient variance curve was derived from a revised hypsometric curve developed using the relief energy of topographic profiles. Using the gradient variance curve, found was the grid size with which the change in relief energy got the peak point. The grid size at the peak point was determined as the scale factor for the study area. In order to investigate the performance of the procedure based on the gradient variance curve, it was applied to determination of the site-specific scale factors of 3 different terrain conditions; highly-rugged, moderately-rugged and relatively less-rugged. The TPI associated with the corresponding scale factors by study site was, then, determined and used in classifying the land-forms. According to the results of this study, the scale factor gets shorter with more rugged terrain conditions. It was also found that the numbers of valleys and ridges estimated with TPI show almost the same trends as those of the observed and the scale factors tends to approach to the mean distance of ridges.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.559-568
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• 2012

White (Lohmann LSL) and Brown (ATAK-S) laying hens, were reared under organic and conventional cage rearing systems, and the effects of the rearing system on performance parameters, egg production, egg characteristics, and immune response were investigated. For this purpose, a total of 832 laying hens of two commercial hybrids, i.e., 416 white (Lohmann LSL) and 416 Brown (ATAK-S) layers, were used. The experiment lasted between 23 and 70 wk of age. In this study, the white layers yielded more eggs as compared to the brown layers in both organic and conventional production systems. Egg weight exhibited a similar pattern to that of laying performance. However, the total hen-housed egg number for the white birds in the organic system was fewer than that of white birds in the conventional cage facility; conversely, a contradictory tendency was observed for the brown birds. Livability of the white layers in the organic system was remarkably lower (14%) than that of the brown line, whereas the white line survived better (3.42%) than their brown counterparts in conventional cages. The feed conversion ratio of the white hens was markedly inferior in the organic system as compared to that of the white hens in the conventional system, whereas relatively lower deterioration was reported in brown layers when reared in an organic system. The organic production system increased egg albumen height and the Haugh unit in eggs of the brown layers. The yolk color score of organic eggs was lower than that of conventional eggs for both brown and white hens. The egg yolk ratio of eggs from white layers was found to be higher in organic eggs as compared to those obtained in the conventional system. All organic eggs had heavier shells than those produced in the conventional system. Eggs from brown layers had more protein content than eggs from white layers. Neither housing systems nor genotype influenced egg yolk cholesterol concentration. When compared to conventional eggs, n-3 fatty acid content was lower in organic eggs, and the n-6:n-3 ratio was higher in organic eggs. In conclusion, two hen genotypes showed different responses in terms of performance and egg quality to two different rearing systems. A commercial white strain produced more eggs with higher egg quality as compared to a native brown strain. The brown strain was found to have adapted well to organic production conditions when survival and total egg number was taken into consideration.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.285-287
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• 2016

Background: The efficacy of standard treatment of Helicobacter pylori (H. pylori) is declining because of antibiotic resistance. Clarithromycin resistance is also increasing in many Asian countries. The aim of this study was to determine the antibiotic susceptibility patterns of H. pylori infection and clinical association in Laos. Materials and Methods: A total of 329 Lao dyspeptic patients who underwent gastroscopy at Mahosot Hospital, Vientiane, Laos during December 2010-March 2012 were enrolled in this study. During gastroscopy, 4 biopsies were collected (2 each from the antrum and body) for CLO-test and histopathology. Only the positive CLO-test gastric tissues was stored at $-80^{\circ}C$ in a freezer until DNA was extracted and a GenoType$^{(R)}$HelicoDR test was conducted for detecting mutations in the rrl gene encoding 23S rRNA (clarithromycin resistance) and mutations in gyrA gene (fluoroquinolone resistance). Results: Of the total, 119 Lao patients (36.2%) were infected with H. pylori including 59 males (49.6%) and 60 females (50.4%) with a mean age of 46 years. Clarithromycin and fluoroquinolone resistance of H. pylori infection was demonstrated in 15 (12.6%) and 16 strains (13.4%) respectively. In clarithromycin resistance, the number of patients who had education above primary school and $BMI{\geq}25kg/m^2$ were significantly higher than those who had education below primary school and BMI<$25kg/m^2$ (23.1% vs 7.5%, P-value= 0.036 and 20.5% vs 8%, P-value= 0.048, respectively). In fluoroquinolone resistance, the number of lowland Lao was significantly higher than those of non-lowland (highland and midland) Lao ethnic groups (16.7% vs 0%, P-value= 0.039). Conclusions: H. pylori infections remain common in Laos. Clarithromycin and fluoroquinolone resistance with H. pylori infection are growing problems. Education above primary school and $BMI{\geq}25kg/m^2$ might be predictors for clarithromycin resistance and lowland Lao ethnicity might be predictors for fluoroquinolone resistance with H. pylori infection in Laos.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.838-843
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• 2002

The objectives of this study were to examine growth performance and meat quality by three different feeding patterns in Korean native cattle (KNC). In each of 3 years, fifteen KNC were randomly assigned in a (3 feeding management)${\times}$(3 sex) factorial design experiment; thus, in total, there were 5 animals in each of the 9 treatments. The three feeding management treatments were longterm (24 month) restriction feeding (LTFR), long-term restriction feeding-hormone implant (LTFR-tH), and short-term (18 month) nonrestriction feeding (STFNR). Three sexes were bull, steer, and heifer. Concentrate diet was fed restriction-feeding method based on body weight in LTFR and LTFR-tH. However, the diet was fed ad libitum in STFNR. Hormonal implantation was made three times with M-$PO^{TM}$ for bulls and with F-$TO^{TM}$ for heifers at 18, 20, 22 month of age in LTFR-tH. Animal were purchased from the local cattle market and managed in two local farms and at the university research unit. Animals were slaughtered at 24 months for long-term trial and at 18 month for short-term trial. The growth rate was the highest in bulls and the lowest in heifers. However, the differences were diminished in F-$TO^{TM}$ implanted heifers. The average daily gain was high in STFNR due to ad libitum feeding. The carcass grade was similar among the treatments on percentage bases. Hormonal implants improved significantly the meat quality grade in all sexes. Castration increased body fat content and improved meat quality grade by intramuscular fat deposition. In conclusion, long-term feeding and hormone treatment increased meat quality grade more than short-term feeding. However, ADG was higher in the short-term trial although feedefficiency was lower.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.3
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• pp.432-438
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• 2017

Objective: The objective of this study was to evaluate the effect of combinations of $NaNO_2$ and NaCl concentrations on Listeria monocytogenes (L. monocytogenes) growth in emulsion-type sausage. Methods: Emulsion-type sausages formulated with different combinations of $NaNO_2$ (0 and 10 ppm) and NaCl (1.00%, 1.25%, and 1.50%) were inoculated with a five-strain L. monocytogenes mixture, and stored at $4^{\circ}C$, $10^{\circ}C$, and $15^{\circ}C$, under aerobic or vacuum conditions. L. monocytogenes cell counts were measured at appropriate intervals, and kinetic parameters such as growth rate and lag phase duration (LPD) were calculated using the modified Gompertz model. Results: Growth rates increased (0.004 to 0.079 Log colony-forming unit [CFU]/g/h) as storage temperature increased, but LPD decreased (445.11 to 8.35 h) as storage temperature and NaCl concentration increased. The effect of combinations of NaCl and low-$NaNO_2$ on L. monocytogenes growth was not observed at $4^{\circ}C$ and $10^{\circ}C$, but it was observed at $15^{\circ}C$, regardless of atmospheric conditions. Conclusion: These results indicate that low concentrations of $NaNO_2$ and NaCl in emulsion-type sausage may not be sufficient to prevent L. monocytogenes growth, regardless of whether they are vacuum-packaged and stored at low temperatures. Therefore, additional techniques are necessary for L. monocytogenes control in the product.

• Korean Journal of Biological Psychiatry
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• v.5 no.2
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• pp.243-247
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• 1998

The authors tried to confirm the significant changes of plasma homovanillic acid(HVA) concentration after insulin administration in comparison with those of usual diurnal variation in the same subjects. Male patients with schizophrenia taking neuroleptics were participated in a study of diurnal variation and insulin induced dopaminergic perturbation, with multiple samplings at baseline, 30minutes, 60minutes and 90minutes after insulin administration(n=18). Ten patients were sampled at baseline and 60minutes after insulin administration. There was a diurnal variation of plasma HVA concentrations, which decreased gradually from 8 am to 9:30 am. We confirmed that regular insulin(0.1 unit/kg) blocked the normal diurnal variations and increased plasma HVA concentrations. This pattern was not correlated with clinical variables, such as age, onset age, duration of illness and presence of family history. Schizophrenic patients were grouped by the positive and negative syndrome scale. In contrast to our previous study, the concentrations of positive and negative groups were similar at baseline. The HVA concentrations of negative group after insulin administration were higher than those of positive group without statistical significance. We have a plan to modify the current insulin-HVA method. In the near future, we will try to confirm whether the modified insulin-HVA method can be used as a biological indicator for the elucidation of complex clinical manifestations of schizophrenia.

• Korean Journal of Materials Research
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• v.10 no.7
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• pp.478-481
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• 2000

Single phase $Pb(Mg_{1/3}Nb_{2/3})O_3$ ceramics doped by 10 mol% of electron donors such as $La^3,\; Pr^{3+,4+},\; Nd^{3+},\; Sm^{3+}$, were synthesized and their B-site cationic ordering structures were investigated by XRD and TEM. In the XRD patterns, only fundamental reflections were observed for the undoped $Pb(Mg_{1/3}Nb_{2/3})O_3$, while the (h/2 $\textsc{k}$/2ι/2)(h,$\textsc{k}$,ι all odd) superlattice reflections resulting from the 1:1 ordering induced unit cell doubling were also observed for the donor-doped $Pb(Mg_{1/3}Nb_{2/3})O_3$. In the TEM selected area diffraction patterns, the (h/2 k/2 l/2)(h,k,l all odd) superlattice reflection spots as well as the fundamental reflection spots were observed for all the samples, but the relative intensities of the superlattice reflection spots to the fundamental reflection spots were significantly enhanced by the donor-doping. In the TEM dark-field images, antiphase boundaries were observed only for the donor-doped $Pb(Mg_{1/3}Nb_{2/3})O_3$. It was therefore experimentally verified that doping by electron donors such as $La^3,\; Pr^{3+,4+},\; Nd^{3+},\; Sm^{3+}$, enhances the B-site cationic 1:1 ordering in $Pb(Mg_{1/3}Nb_{2/3})O_3$. These experimental results were interpreted in terms of the charge compensation mechanism.