• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.291-304
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• 2023

Harmful algal blooms (HABs) have become an increasing concern in terms of human health risks as well as aesthetic impairment due to their toxicity. The reduction of water pollutants, especially nutrients from non-point sources in a reservoir watershed, is fundamental for HABs prevention. We investigated the pollutant removal efficiencies of a constructed wetland to evaluate its feasibility as a method for controlling non-point sources located in the Annaecheon stream within the Daecheong Reservoir watershed. The overall removal efficiencies of pollutants were as follows: BOD 14.3%, COD 17.9%, SS 50.0%, T-N 19.0%, and T-P 35.4%. These results indicate that constructed wetlands are effective in controlling pollutants from non-point sources. The seasonal variation in removal efficiency depended on the specific pollutants. The removal efficiencies of BOD, COD, and T-N were stable throughout the year, except during winter, which might have been influenced by lower microorganism activity. In contrast, T-P showed a consistent removal efficiency even during the winter season, suggesting that the wetland can reduce external phosphorus loading to the reservoir. Regarding the effects of pollutant loadings on removal efficiency, the effluent concentrations of all pollutants were significantly decreased compared to those in the influent in case of middle and high loadings. This demonstrates that constructed wetlands can handle high pollutant loads, including the initial runoff during rainfall, to prevent reservoir eutrophication. Despite the various strengths of wetland water purification, there are limitations as passive treatment. Therefore, more case studies should be conducted to suggest optimum operational conditions for constructed wetlands, taking into consideration reservoir-specific characteristics.

• Journal of Gastric Cancer
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• v.23 no.4
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• pp.609-621
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• 2023

Purpose: Determination of optimal treatment strategies for HER2-positive advanced gastric cancer (AGC) in randomized trials is necessary despite difficulties in direct comparison between trastuzumab deruxtecan (T-DXd) and nivolumab as third or later-line treatments. Materials and Methods: This single-institution, retrospective study aimed to describe the real-world efficacy and safety of T-DXd and nivolumab as ≥ third line treatments for HER2-positive AGC between March 2016 and May 2022. Overall, 58 patients (median age, 64 years; 69% male) were eligible for the study (T-DXd group, n=20; nivolumab group, n=38). Results: Most patients exhibited a HER2 3+ status (72%) and presented metastatic disease at diagnosis (66%). The response rates of 41 patients with measurable lesions in the T-DXd and nivolumab groups were 50% and 15%, respectively. The T-DXd and nivolumab groups had a median progression-free survival of 4.8 months (95% confidence interval [CI], 3.3, 7.0) and 2.3 months (95% CI, 1.5, 3.5), median overall survival (OS) of 10.8 months (95% CI, 6.9, 23.8) and 11.7 months (95% CI, 7.6, 17.1), and grade 3 or greater adverse event rates of 50% and 2%, respectively. Overall, 64% patients received subsequent treatment. Among 23 patients who received both regimens, the T-DXd-nivolumab and nivolumab-T-DXd groups had a median OS of 14.0 months (95% CI, 5.0, not reached) and 19.3 months (95% CI, 9.5, 25.1), respectively. Conclusions: T-DXd and nivolumab showed distinct efficacy and toxicity profiles as ≥ third line treatments for HER2-positive AGC. Considering the distinct features of each regimen, they may help clinicians personalize optimal treatment approaches for these patients.

• Journal of Wetlands Research
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• v.26 no.1
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• pp.1-9
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• 2024

In this study, a HSPF model was developed to simulate runoff and water quality in the Haebancheon watershed, which has a high land area ratio and population density among the West Nakdong River watersheds. Various non-point source pollution control strategies were applied, and the reduction in pollutant loads and the exceedance rate of water quality standards were analyzed. The scenarios included basic road cleaning for reducing pollutant loads, runoff reduction measures considering extensive low-impact development techniques, and inflow reduction measures to mitigate non-point source pollution entering the river. In the first step, practical conditions such as the number of vehicles for road cleaning in Kimhae City were considered, while for the second and third steps, it was assumed that 50% of the applicable land use area was used to be applicable for the LID techniques. As a result of applying all three measures, it was analyzed that the BOD pollutant load could be reduced by 58.28%, T-N by 58.49%, and T-P by 51.56%. Furthermore, the 60th percentile of water quality measurements accumulated over 5 years was set as the target water quality, and a flow-duration curve was constructed. The exceedance rate of the flow-duration curve before and after applying non-point source pollution reduction measures was analyzed. As a result, for BOD, the exceedance rate decreased from 41.57% before applying the measures to 16.32% after, showing a 25.25% reduction in the exceedance rate. For T-N, the exceedance rate decreased significantly from 40.31% before the measures to 22.84% after, and for T-P, it decreased significantly from 62.43% to 27.22%.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.106-116
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• 2024

Purpose: This paper conducts IoT and CCTV-based safety monitoring to analyze accidents and potential risks occurring at construction sites, and detect and analyze risks such as falls and collisions or abnormalities and to establish a system for early warning using devices like a walkie-talkie and chatbot service. Method: A safety management service model is presented through smart construction technology case studies at the construction site and review a relevant literature analysis. Result: According to 'Construction Accident Statistics,' in 2021, there were 26,888 casualties in the construction industry, accounting for 26.3% of all reported accidents. Fatalities in construction-related accidents amounted to 417 individuals, representing 50.5% of all industrial accident-related deaths. This study suggests implementing AI chatbot services for construction site safety management utilizing IoT-based health monitoring technologies in smart construction practices. Construction sites where stakeholders such as workers participate were demonstrated by implementing an artificial intelligence chatbot system by selecting major risk areas within the workplace, such as scaffolding processes, openings, and access to hazardous machinery. Conclusion: The possibility of commercialization was confirmed by receiving more than 90 points in the satisfaction survey of participating workers regarding the empirical results of the artificial intelligence chatbot service at construction sites.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.1
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• pp.52-60
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• 1995

This experiment was carried out to determine the effect of nitrogen application level of cattle sluny(T1:150, T3:250, T53.50 kglha) and chemical fertilizer(T2:150, T4:250, T6:350 kg/ha) on the growth characteristics, dry matter yield and chemical soil property of Sorghum-Sudangrass hybrid [Sorghum bicolor L. Moench]. The results obtained are summarized as follows: Mean stem diameter was significantly increased by increasing nitrogen application level of cattle slurry and chemical fertilizer. Especially, T6 treatment was the highest as 11.1 mm, while T1 treatment w a the lowest as 0.3 mrn. According to the same level of nitrogen application, cattle slurry treaunent(T1, T3 and T5) were showed a lower mean stem hardness than chemical fertilizer treatment(T2, T4 and T6). Especially, T3 treatment was the softest at 0.7 kg/$cm^2$. The dead stubble and tiller number were increased by increasing nitrogen level of cattle slurry and chemical fertilizer(P

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.185-191
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• 2005

An experiment was conducted to study the effect of feeding ammoniated wheat straw treated with HCl on blood biochemical profiles in growing male buffalo (Bubalus bubalis) calves. Twenty-four growing male buffalo calves (one year of age, 88.54${\pm}$3.81 kg average body weight) were divided into three groups in a completely randomized design on the basis of their body weight. Animals in all the three groups were fed on concentrate mixture. In addition, they were offered wheat straw, ammoniated wheat straw (4% urea at 50% moisture level) and HCI treated ammoniated wheat straw (4% urea at 50% moisture level and HCl added to trap 30% of the NH3 evolved) in groups I, II and III, respectively for a period of 180 days, as per Kearl (1982) for body weight gain of 500 g/d. In all diets, concentrate:roughage ratio was fixed at 50:50 and were made isonitrogenous by adjusting CP levels of conc. mixtures. Blood was collected from jugular vein of each buffalo calf at the beginning and subsequently at two months interval of experimental feeding. Due to urea-ammoniation, the CP content of wheat straw increased from 2.90 to 6.96% and addition of HCl along with urea further increased the CP content to 10.09%. In all the three groups, the mean values of plasma glucose (mg %) and serum globulin (g %), showed a decreasing trend, while the mean value of serum TP (g %), serum A:G ratio, serum urea (mg %), serum creatinine (mg %), serum ALP (KA units), SGOT (units/ml.), SGPT (units/ml), serum T$_3$ and T$_4$ (ng/ml) showed an increasing trend with the advancement of feeding period. The cumulative period mean values of serum TP (6.15 to 6.20 g %), serum albumin (3.07 to 3.18, g %), serum globulin (2.98 to 3.09, g %), serum A:G ratio (1.03 to 1.10), serum ALP (23.15 to 23.63, KA units), serum T$_3$ (1.20 to 1.23 ng/ml) and serum T$_4$ (21.33 to 21.88 ng/ml) were comparable among the groups. The cumulative period mean plasma glucose (mg %) in group III (57.28) was similar to groups I (55.31) and II (59.41), however, the cumulative period mean plasma glucose in group II was significantly (p<0.01) higher than group I. The cumulative period mean serum urea (mg %) in group III (47.34) was significantly (p<0.001) higher than group I (38.38) and II (42.24), which were statistically alike. However, the cumulative period mean serum creatinine values (mg %) in groups II (1.43) and III (1.52) were similar and were significantly (p<0.01) higher than group I (1.24). The cumulative period mean SGOT (units/ml) in groups I, II and III was 91.71, 96.04 and 96.64, respectively. Similarly the cumulative period mean SGPT (units/ml) was 19.00, 19.93 and 20.01 in groups I, II and III, respectively. The cumulative period mean values of SGOT (p<0.05) and SGPT (p<0.001) in groups II and III were similar and were significantly higher than group I. The cumulative period mean serum T$_3$ and T$_4$ values in groups I (1.21 and 21.81), II (1.23 and 21.42) and III (1.20 and 21.33) were comparable. From the present study it may be concluded that feeding of AWS treated with and without HCI to growing male buffalo calves for 180 days had no significant adverse effect on blood biochemical profile.

• Journal of Korea Water Resources Association
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• v.41 no.11
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• pp.1079-1094
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• 2008

This study is to evaluate the impact of varying spatial resolutions on the uncertainty of Soil and Water Assessment Tool (SWAT) predicted streamflow, non-point source (NPS) pollution loads transport in a small agricultural watershed (1.21 $km^2$) for three cases of model input; Case A is the combination of 2 m DEM, QuickBird land use, Case B is the combination of 10 m DEM, 1/25,000 land use, and Case C is the combination of 30 m DEM, Landsat land use, soil data is used 1/25,000 for three cases respectively. The model was calibrated for 2 years (1999-2000) using daily streamflow and monthly water quality records, and verified for another 2 years (2001-2002). The average Nash and Sutcliffe model efficiency was 0.59 for streamflow and RMSE were 2.08, 4.30 and 0.70 tons/yr for sediment, T-N and T-P respectively. The model was run for a small agricultural watershed with three cases of spatial input data. The hydrological results showed that output uncertainty was biggest by spatial resolution of land use. Streamflow increase the watershed average CN value of QucikBird land use was 0.4 and 1.8 higher than those of 1/25,000 and Landsat land use caused increase of streamflow. On the other hand, The NPS loadings from the model prediction showed that the sediment, T-N and T-P of QuickBird land use (Case A) showed 23.7 %, 43.3 % and 48.4 % higher value than 1/25,000 land use (Case B) and 50.6 %, 50.8 % and 56.9 % higher value than Landsat land use (Case C) respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.1
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• pp.21-30
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• 1997

The present study reports the density, growth and production of a razor clam, Sinollovacula constricta, which is known to be one of the important fishreies catches from the Korean tidal flat. The annual yield reached to about 6,000 metric tons per year till 1994. The study was conducted on the Hwaseong tidal flat located on the central west coast, 40 kilometers south-west from Seoul. The annual yield of the razor clam in this area reached to about 50% of the total catch from the whole Korean coast. Samples were colleted monthly at 14 occasions from May 1992 to August 1993. Density of S. constricta ranged from 92~165 individuals per square meter during the study period. General trend of decreasing density was observed when the animal became older, but an exception was the year class of 1991 whose density was lower than that of 1990. The size of the shell was clearly separated into two classes during fall and winter (from September to February), however, the maximum frequency of the length of small size classes moved to right after February. It indicates a fast growth of young clams from spring to summer. Fast growth of the shell could also be examined by the growth curve. The shell growth of the whole life span was described by the von Bertalanffy equation of $L_t=89.3{\times}[1{\exp}\{-0.58{\times}(t+0.73\}]$. The growth in flesh dry weight was well fitted to the Gompertz growth model with the equation, $W_t=5.00{\times}{\exp}\{-4.31{\times}{\exp}(-0.043{\times}t)\}$. The clam lost about 30% of the body weight during spawning in August. The annual production calculated based on the data from September 1992 to August 1993 amounted to 150 g $DW{\cdot}m^{-2}{\cdot}yr^{-1}$ which was 2~50 fold higher than those of other bivalves occurred in Korea. This estimate was patitioned by each year classes; 87.5 by 1992, 53.4 by 1991, 59.0 by 1990 and -30.0 g $DW{\cdot}m^{-2}{\cdot}yr^{-1}$ by 1989 year class.

• Journal of Food Hygiene and Safety
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• v.37 no.5
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• pp.323-327
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• 2022

The mineral content of Tricholoma matsutake was evaluated for comparison of mineral contents according to the area of cultivation. Ten domestic and thirty Chinese (10 Yanji, 10 Yunnan and 10 Tibet) T. matsutake specimens were assessed using an atomic absorption spectrophotometer (AAS) and inductively coupled plasma mass spectrometer (ICP-MS). The Na, Mg, K, and Ca contents of domestic T. matsutake were 128.12±85.25 mg/kg, 218.52±105.35 mg/kg, 7,534.58±2,691.52 mg/kg, and 17.69±7.14 mg/kg, respectively, while those of Yanji T. matsutake were 124.89±57.24 mg/kg, 64.07±27.52 mg/kg, 1,439.18±311.04 mg/kg, and 10.88±4.52 mg/kg, respectively. The Na, Mg, K, and Ca contents of Yunnan T. matsutake were 90.78±23.23 mg/kg, 77.40±28.36 mg/kg, 1,446.29±126.33 mg/kg, and 28.42±5.18 mg/kg respectively, while those of Tibet T. matsutake were 143.50±41.54 mg/kg, 124.64±50.18 mg/kg, 3,530.95±2,714.99 mg/kg, and 21.05±8.71 mg/kg, respectively. The Cu contents of domestic, Yanji, Yunnan, and Tibet T. matsutake were 105.43±32.97 mg/kg, 19.92±8.95 mg/kg, 54.51±16.91 mg/kg, and 64.80±23.01 mg/kg, respectively. Both domestic and Chinese T. matsutake samples showed significantly different K, Mg, and Cu levels in this study. Therefore, a comparative evaluation of the K, Mg, and Cu contents of multiple domestic and Chinese T. matsutake varieties is needed to determine the appropriate area of cultivation in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.1015-1019
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• 2003

A 50 day feeding trial was conducted with White Leghorn (WL) laying hens, 42 weeks old, to determine if feeding of varying levels of aflatoxin (AF), ochratoxin A (OA) or their combinations has any effect on their performance and egg quality parameters. Feeding of $T_4$, $T_7$, $T_8$, $T_9$ and $T_10$ caused significant reduction in feed intake of hens. Hen day egg productions were significantly reduced at all the levels of toxins except 0.5 ppm of AF. Maximum reduction in egg production was noticed at 2 and 4 ppm of AF and OA, respectively. Average body weight and egg weight were not affected by toxin feeding. The feed efficiency in terms of net feed efficiency and feed consumed per dozen egg produced was significantly reduced at higher levels of both the toxins and their combinations. Feed consumption for production of 1 kg egg mass remained uninfluenced due to aflatoxin feeding whereas significant increase in the value of the same was noticed at 4 ppm level of OA and combination of 1 and 2 ppm of AF and 2 and 4 ppm of OA ($T_9$ and $T_10$), respectively. Various levels of OA (1-4 ppm) and all the combination of two toxins ($T_8$, $T_9$ and $T_10$) significantly altered the shape index of eggs in laying hens. The shell thickness was significantly reduced by higher level of AF (2 ppm), OA (2 and 4 ppm) and their combination. Albumen index, Haugh Unit and yolk index remained unchanged due to incorporation of toxins in the diet. It is concluded that AF, OA either singly or in combination at higher levels could depress the performance in terms of egg production and feed efficiency significantly. The egg quality parameters i.e. shape index and shell thickness were also significantly affected.