• Korean Journal of Clinical Laboratory Science
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• v.53 no.4
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• pp.342-352
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• 2021

We used data from the 7th Korea National Health and Nutrition Examination Survey (KNHANES) (2016~2018) to investigate an association between high sensitivity C-reactive protein (hsCRP) and uric acid in the obese. Obesity was defined as a body mass index (BMI) of 25 kg/m² or more, severe obesity as a BMI of 30 kg/m² or more, and morbid obesity as a BMI of 35 kg/m² or more. In the complex samples multiple logistic regression, despite adjustment by adding major risk factors, the odds ratio (OR) for obesity was higher in the group with high levels of both, hsCRP and uric acid than the reference group at all stages (obesity, OR 1.89, P<0.001 vs. severe obesity, OR 5.04, P<0.001 vs. morbid obesity, OR 8.20, P<0.001). The association between hsCRP and uric acid in obese patients increased from 1.89 to 8.20 as the obesity level increased, suggesting that participants with increased BMI were significantly affected by hsCRP and uric acid. Moreover, the interaction between hsCRP and uric acid was statistically significant even in the model corrected for major confounding factors (P for interaction=0.009).

• Journal of Korean Society of Water and Wastewater
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• v.35 no.5
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• pp.323-334
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• 2021

Pilot-scale coagulation and sedimentation processes were operated to investigate the T-P (Total phosphorus) removal efficiency. A multiple regression model was also derived to predict the water quality improvement effect with river water characteristics. The inflow rates for the pilot-scale facility were 157-576 m³/day, and the coagulant doses were in the range of 13.7-58.5 mg/L (average 38.9 mg/L) for PAC (Poly alum chloride) and 16.5-62.1 mg/L (average 36.0 mg/L) for alum. The results found that the influent BOD (Biochemical oxygen demand) and T-P concentrations were 4.9 mg/L and 0.115 mg/L, and the removal efficiencies were 52.7% and 59.4%, respectively. T-P removal efficiencies on wet weather days were higher by 10% than dry weather days because influent solids influenced T-P's coagulation process. The pH of river water was 6.9-7.8, and the average pH was 7.3. Although the pH variation was not significant, the trend showed that the treatment efficiency of T-P and PO₄-P removal increased. Thus, the pH range considered in this study seems to be appropriate for the coagulation process, which is essential for phosphorous removal. The T-P removal efficiencies were 19.6-93.3% (average 59.2%) for PAC and 16.4-98.5%(average 55.9%) for alum; thus, both coagulants showed similar results. Furthermore, the average coagulant doses were similar at 42.4 mg/L for PAC and 41.3 mg/L for alum. When the T-P concentration of the effluent was compared by the [Al]/[P] ratio, the phosphorus concentration of the treated water decreased with an increasing [Al]/[P] ratio, and the lowest T-P concentration range appeared at the [Al]/[P] ratio of 10-30. A seasonal multiple regression analysis equations were derived from the relationships between 10 independent and dependent variables (T-P concentration of effluent). This study could help lake water quality maintenance, reduce eutrophication, and improve direction settings for urban planning, especially plans related to developing waterfront cities.

• Journal of the Korean GEO-environmental Society
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• v.22 no.3
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• pp.37-43
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• 2021

This study aimed to calculate the amount of change in soil carbon due to changes in land cover. Among the various soil carbon models, the InVEST Carbon Storage and Sequestration module was used. LULC is one of the leading factors affecting soil carbon. Therefore, this study compared the total amount of soil carbon due to changes in LULC in 2000 and 2010 across the Republic of Korea, and calculated the changes in each administrative district (city). Changes in LULC in Korea were mainly due to the increase in developed and dry areas and the decrease in grassland, indicating changes in soil carbon. The total amount of soil carbon changes in South Korea has been reduced by 11.48 (millions) in 10 years. The amount of soil carbon by administrative region decreased in most cities and provinces, but Jeju Island, in exception, showed an increase in soil carbon. Among the cities and provinces except Jeju Island, Seoul showed the smallest decrease, with a decrease of 0.033 (million t). On the contrary, the largest number of attempts to decrease was to Gyeongsangbuk-do, which saw a total decrease of 2.893 (million t). Jeju Island is the only soil carbon-increasing area with an increase of 0.547 (millions) and the agricultural area has increased 2.1 times in 10 years. In the case of soil carbon, the construction of ground observation data at the national unit is insufficient, and verification will need to be carried out through linked analysis using multiple models in the future.

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.209-220
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• 2021

The effect of body composition such as lean mass and fat mass on bone mineral density (BMD) is complex and still controversial. In this study, we investigated the relationship between body composition and bone mineral density using nation-wide data from 2008 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES) in 2,139 men and 2,193 postmenopausal women aged 50 years or older. Subjects with history of medication for osteoporosis or with diseases or malignancy affecting bone metabolism were excluded. Data of anthropometric measurements and demographic characteristics were collected by trained examiner. Fasting blood sample was obtained for blood chemistry analysis. BMD of the lumbar spine, total femur, and femoral neck, and body composition such as total lean mass (TLM), total fat mass (TFM), truncal fat mass (TrFM) were measured using dual-energy X-ray absorptiometry (DXA). There were significant positive correlations between body composition indices such as lean mass and fat mass with BMD. In multiple regression analysis, TLM was positively associated with BMD after adjusting age, body mass index, monthly house income, education level, physical activity, daily calcium intake and vitamin D concentration in both men and postmenopausal women. BMD at lumbar spine and femur in lowest quartile of TLM was significantly lower than other quartiles after adjusting those confounding factors in both gender. TrFM was negatively associated with total femur BMD in male and femur neck BMD in postmenopausal women after adjusting confounding factors. In conclusion, TLM is very important factor in maintaining BMD in subjects aged 50 years or older in men and postmenopausal women.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1141-1180
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• 2022

The application of satellite imageries has increased in the field of hydrology and water resources in recent years. However, challenges have been encountered on obtaining accurate evapotranspiration and soil moisture. Therefore, present researches have emphasized the necessity to obtain estimations of satellite-based evapotranspiration and soil moisture with related development researches. In this study, we presented the research status in Korea by investigating the current trends and methodologies for evapotranspiration and soil moisture. As a result of examining the detailed methodologies, we have ascertained that, in general, evapotranspiration is estimated using Energy balance models, such as Surface Energy Balance Algorithm for Land (SEBAL) and Mapping Evapotranspiration with Internalized Calibration (METRIC). In addition, Penman-Monteith and Priestley-Taylor equations are also used to estimate evapotranspiration. In the case of soil moisture, in general, active (AMSR-E, AMSR2, MIRAS, and SMAP) and passive (ASCAT and SAR)sensors are used for estimation. In terms of statistics, deep learning, as well as linear regression equations and artificial neural networks, are used for estimating these parameters. There were a number of research cases in which various indices were calculated using satellite-based data and applied to the characterization of drought. In some cases, hydrological cycle factors of evapotranspiration and soil moisture were calculated based on the Land Surface Model (LSM). Through this process, by comparing, reviewing, and presenting major detailed methodologies, we intend to use these references in related research, and lay the foundation for the advancement of researches on the calculation of satellite-based hydrological cycle data in the future.

• Korean Journal of Psychosomatic Medicine
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• v.31 no.1
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• pp.1-9
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• 2023

Patients with neurocognitive disorder show behavioral psychological symptoms such as agitation, aggression, depression, and wandering, as well as cognitive decline, which puts a considerable burden on patients and their families. For the treatment of behavioral psychological symptoms, patient-centered, non-pharmacological treatment should be used as a first line approach. This paper describes non-pharmacological interventions to manage and treat behavioral psychological symptoms in patients with neurocognitive disorder. In order to control behavioral psychological symptoms such as agitation, depression, apathy, insomnia, and wandering, it is important to identify and evaluate factors such as environmental changes and drugs, and then solve such problems. Non-pharmacological interventions include reassurance, encourage, distraction, and environmental change. It is necessary to understand behavior from a patient's point of view and to approach the patient's needs and abilities appropriately. Reminiscence therapy, music therapy, aroma therapy, multisensory stimulation therapy, exercise therapy, light therapy, massage therapy, cognitive intervention therapy, and pet therapy are used as non-pharmacological interventions, and these approaches are known to improve symptoms such as depression, apathy, agitation, aggression, anxiety, wandering, and insomnia. However, the quality of the evidence base for non-pharmacological approaches is generally lower than for pharmacological treatments. Therefore, more extensive and accurate effectiveness verification studies are needed in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.376-386
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• 2023

Due to climate changes, landslide hazards in the Republic of Korea (hereafter South Korea) continuously increase. To establish the effective landslide mitigation strategies, such as erosion control works, landslide hazard estimation in the long-term perspective should be proceeded considering the influence of climate changes. In this study, we examined the change in landslide-damaged areas in South Korea responding to climate change scenarios using the multivariate regression method. Data on landslide-damaged areas and rainfall from 1981-2010 were used as a training dataset. Sev en indices were deriv ed from rainfall data as the model's input data, corresponding to rainfall indices provided from two SSP scenarios for South Korea: SSP1-2.6 and SSP5-8.5. Prior to the multivariate regression analysis, we conducted the VIF test and the dimension analysis of regression model using PCA. Based on the result of PCA, we developed a regression model for landslide damaged area estimation with two principal components, which cov ered about 93% of total v ariance. With climate change scenarios, we simulated landslide-damaged areas in 2030-2100 using the regression model. As a result, the landslide-damaged area will be enlarged more than the double of current annual mean landslide damaged area of 1981-2010; It infers that landslide mitigation strategies should be reinforced considering the future climate condition.

• Ecology and Resilient Infrastructure
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• v.10 no.4
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• pp.107-115
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• 2023

High turbidity in source water can have adverse effects on water treatment plant operations and aquatic ecosystems, necessitating turbidity management. Consequently, research aimed at predicting river turbidity continues. This study developed a multi-class classification model for prediction of turbidity using LightGBM (Light Gradient Boosting Machine), a representative ensemble machine learning algorithm. The model utilized data that was classified into four classes ranging from 1 to 4 based on turbidity, from low to high. The number of input data points used for analysis varied among classes, with 945, 763, 95, and 25 data points for classes 1 to 4, respectively. The developed model exhibited precisions of 0.85, 0.71, 0.26, and 0.30, as well as recalls of 0.82, 0.76, 0.19, and 0.60 for classes 1 to 4, respectively. The model tended to perform less effectively in the minority classes due to the limited data available for these classes. To address data imbalance, the SMOTE (Synthetic Minority Over-sampling Technique) algorithm was applied, resulting in improved model performance. For classes 1 to 4, the Precision and Recall of the improved model were 0.88, 0.71, 0.26, 0.25 and 0.79, 0.76, 0.38, 0.60, respectively. This demonstrated that alleviating data imbalance led to a significant enhancement in Recall of the model. Furthermore, to analyze the impact of differences in input data composition addressing the input data imbalance, input data was constructed with various ratios for each class, and the model performances were compared. The results indicate that an appropriate composition ratio for model input data improves the performance of the machine learning model.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.435-440
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• 2009

Purpose : The concentration of soluble transferrin receptor (sTfR) is estimated as an iron parameter to evaluate erythropoiesis and iron status. The aim of our study is to evaluate the correlation between sTfR concentration and inflammatory parameters and to distinguish iron deficiency anemia from anemia of inflammation. Methods : One hundred and forty-four infants younger than two years of age who visited Gyeongsang University Hospital for 7 years from 2000 to 2006 were enrolled. Patients who had hemoglobin (Hb) <11 g/dL and ferritin <12 mg/L were excluded. Routine hematologic lab, serum ferritin, sTfR, and inflammatory markers [C-reactive protein(CRP), interleukin-6(IL-6), and absolute neutrophil count (ANC)] were investigated. Results : In all patients, the sTfR concentration showed a correlation with Hb, ferritin, MCV, and ANC, but not with CRP and IL-6. In multiple regression models, positive correlations were found between sTfR concentration and IL-6 (r=0.078, P=0.043), and negative correlations were found between sTfR concentration and ANC (r=-0.117, P=0.033) and MCV (r=-0.027, P=0.009). Conclusion : sTfR concentration was influenced by inflammatory parameters. Therefore, sTfR does not appear to be a useful parameter for discriminating between iron deficiency anemia and anemia of inflammation in infants.

• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.600-610
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• 2004

Background : The plasma B-type natriuretic peptide(BNP) concentration increases with the degree of pulmonary hypertension in patients with chronic respiratory disease. The aim of this study was to examine the prognostic role of BNP in the acute exacerbation of chronic obstructive lung disease (COPD). Method : We selected 67 patients who were admitted our hospital because of an acute exacerbation of COPD. Their BNP levels were checked on admission at the Emergency Department. Their medical records were analyzed retrospectively. The patients were divided into two groups according to their in-hospital mortality. The patients' medical history, comobidity, exacerbation type, blood gas analysis, pulmonary function, APACHE II severity score and plasma BNP level were compared. Results : Multiple logistic regression analysis identified three independent predictors of mortality: $FEV_1$, APACHE II score and plasma BNP level. The decedents group showed a lower $FEV_1$($28{\pm}7$ vs. $37{\pm}15%$, p=0.005), a higher APACHE II score($22.4{\pm}6.1$ vs. $15.8{\pm}4.7$, p=0.000) and a higher BNP level ($201{\pm}116$ vs. $77{\pm}80pg/mL$, p=0.000) than the sSurvivors group. When the BNP cut-off level was set to 88pg/mL using the receiver operating characteristic curve, the sensitivity was 90% and the specificity was 75% in differentiating between the survivors and decedents. On Fisher's exact test, the odds ratio for mortality was 21.2 (95% CI 2.49 to 180.4) in the patients with a BNP level > 88pg/mL. Conclusion : The plasma BNP level might be a predictor of mortality in an acute exacerbation of COPD as well as the $FEV_1$ and APACHE II score.