• International Area Studies Review
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• v.20 no.3
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• pp.45-80
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• 2016

This paper examined, using three indicators, urban area rate, urbanization rate and urban population density upon the status of urbanization since the 2000s in Southeast Asia. This study also carried out an empirical analysis on the effects of urbanization on economic growth using the Williamson's inverted U-shape hypothesis. In addition, this study calculated the thresholds by which urbanization starts to have positive effects on economic growth by using estimated coefficients, and comparatively analyzed each Southeast Asian country's status. The empirical analysis results opposite to the Williamson's hypothesis. This means that the hypothesis asserting that urbanization has positive effects on economic growth in a country with low economic development phase and income level, but that urbanization can have negative effects on economic growth, if a country's income level is beyond a certain level(threshold), is not supported in this study. In summary, the economies of agglomeration represented as localization economy and urbanization economy is realized to some degree in terms of urbanization in Southeast Asia. Also, urbanization in Southeast Asia has positive effects on economic growth through knowledge spillover, the active exchange of ideas and productivity improvement. In examining the meaning of Southeast Asia's urbanization, policy consideration needs to be conducted, and efforts should be made to maximize the positive effects of the economies of agglomeration and knowledge spillover on economic growth.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.2
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• pp.99-107
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• 2020

Fibromyalgia is a disorder characterized by the core symptom of chronic widespread pain, along with fatigue, sleep disturbances, mood changes, and cognitive difficulties. The etiology of fibromyalgia involves a combination of biological factors, such as genetic vulnerability, alterations in pain processing and stress response system ; psychological factors, such as anxiety, depression, anger, and perceived stress ; environmental factors, such as infections, febrile diseases, and trauma. Central sensitization, which is amplified in the process of sensory stimulation, has been emphasized as a key etiological factor, as supported by enhanced wind-up, delayed aftersensation, decreased nociceptive flexion reflex threshold and functional imaging studies. Several guidelines recommend that a multimodal approach be used to treat fibromyalgia, including both pharmacological and non-pharmacological treatments, tailored to each individual, and that clinicians should provide an intellectual framework through sufficient education and emphasis on the importance of self-management. The prevalence of mood disorders, anxiety disorders, and other psychiatric problems is 7-9 times higher in patients with fibromyalgia than in the general population ; moreover, the association between fibromyalgia and certain psychopathologies or sleep problems has also been suggested. Since psychiatric problems, with shared vulnerabilities and risk factors, interact with fibromyalgia bidirectionally and also affect the disease course, an integrated management approach is needed to determine the risk of comorbidities.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.503-514
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• 2021

Rice production with adequate level of area is important for decision making of rice supply and demand policy. It is essential to grasp rice cultivation areas in advance for estimating rice production of the year. This study was carried out to classify paddy rice cultivation in Gimje-si using sentinel-1 SAR (synthetic aperture radar) and UAV imagery in early July. Time-series Sentinel-1A and 1B images acquired from early May to early July were processed to convert into sigma naught (dB) images using SNAP (SeNtinel application platform, Version 8.0) toolbox provided by European Space Agency. Farm map and parcel map, which are spatial data of vector polygon, were used to stratify paddy field population for classifying rice paddy cultivation. To distinguish paddy rice from other crops grown in the paddy fields, we used the decision tree method using threshold levels and random forest model. Random forest model, trained by mainly rice cultivation area and rice and soybean cultivation area in UAV image area, showed the best performance as overall accuracy 89.9%, Kappa coefficient 0.774. Through this, we were able to confirm the possibility of early estimation of rice cultivation area in Gimje-si using UAV image.

• Korean Journal of Radiology
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• v.24 no.12
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• pp.1249-1259
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• 2023

Objective: This study aimed to evaluate the clinical outcomes and cost-effectiveness of dual-energy X-ray absorptiometry (DXA) for osteoporosis screening. Materials and Methods: Eligible patients who had and had not undergone DXA screening were identified from among those aged 50 years or older at Kaohsiung Veterans General Hospital, Taiwan. Age, sex, screening year (index year), and Charlson comorbidity index of the DXA and non-DXA groups were matched using inverse probability of treatment weighting (IPTW) for propensity score analysis. For cost-effectiveness analysis, a societal perspective, 1-year cycle length, 20-year time horizon, and discount rate of 2% per year for both effectiveness and costs were adopted in the incremental cost-effectiveness (ICER) model. Results: The outcome analysis included 10337 patients (female:male, 63.8%:36.2%) who were screened for osteoporosis in southern Taiwan between January 1, 2012, and December 31, 2021. The DXA group had significantly better outcomes than the non-DXA group in terms of fragility fractures (7.6% vs. 12.5%, P < 0.001) and mortality (0.6% vs. 4.3%, P < 0.001). The DXA screening strategy gained an ICER of US$ -2794 per quality-adjusted life year (QALY) relative to the non-DXA at the willingness-to-pay threshold of US$ 33004 (Taiwan's per capita gross domestic product). The ICER after stratifying by ages of 50-59, 60-69, 70-79, and ≥ 80 years were US$ -17815, US$ -26862, US$ -28981, and US$ -34816 per QALY, respectively. Conclusion: Using DXA to screen adults aged 50 years or older for osteoporosis resulted in a reduced incidence of fragility fractures, lower mortality rate, and reduced total costs. Screening for osteoporosis is a cost-saving strategy and its effectiveness increases with age. However, caution is needed when generalizing these cost-effectiveness results to all older populations because the study population consisted mainly of women.

• Journal of Environmental Impact Assessment
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• v.33 no.3
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• pp.99-115
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• 2024

A worldwide effort is underway to utilize urban parks as a means ofresponding to climate change, providing various benefits to citizens. However, it also has several negative effects, such as an increase in pollen allergies. These negative impacts have been defined as ecosystem disservices and discussed globally, although the discussion remains insufficient domestically. In particular, pollen allergies have been discussed as a typical ecosystem disservice, with negative impacts such as an increase in symptoms attributed to higher pollen production or the growth of trees with higher antigenicity. The WHO reports that approximately 30% of the world's population suffers from pollen allergies. Many recent studies indicate that the harm induced by pollen allergies is expected to increase due to changes in the climate and thermal environment. In this context, we aim to diagnose the allergenicity of current urban parks and assess changes according to climate change scenarios. To achieve this goal, we assess pollen allergenicity in Seoul Children's Grand Park using the Urban Green Space Allergenicity Index (IUGZA) as the first step towards discussing ecosystem disservices. We found that the IUGZA value in the target area exceeds the threshold suggested in previous research, causing harm due to pollen allergies and is expected to increase according to climate change scenarios. We conclude that this result indicates that social harm from pollen allergies in urban parks may increase due to climate change. Therefore, we emphasize the necessity of discussing ecosystem disservices in the composition of urban parks.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.3
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• pp.248-256
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• 2024

The purpose of this study was to identify the household air pollutants most significantly impacting hearing loss, using data from the 8th Korea National Health and Nutrition Examination Survey. Of the 1,980 participants, those with missing data were excluded from the study population, resulting in the final inclusion of 298 participants. Mild hearing loss is defined as a unilateral or bilateral pure-tone threshold average (PTA) of 26~40 dB, and moderate hearing loss is defined as a unilateral or bilateral PTA of 41 dB or higher. The mean of the PTAs for both ears is defined as the sum of the PTAs of the left and the right ears divided by 2. Complex samples multiple logistic regression analysis revealed that formaldehyde exposure independently significantly increased the risk of moderate hearing loss (odds ratio=1.050, P<0.001). Additionally, in the complex samples general linear model, toluene exposure (B=0.026, P<0.001) was found to be independently significantly associated with an increase in the mean of PTAs for both ears, where a higher mean of the PTAs for both ears indicates a decrease in hearing ability. These results suggest a strong association between hearing loss and the presence of toluene or formaldehyde in indoor air.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.359-369
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• 2018

Harmful algal blooms (HABs) are a serious problem for public health and fisheries industries, thus there exists a need to investigate the possible ways for effective control of HABs. In the present study, we investigated the algicidal effects of a newly developed GreenTD against the HABs (Chattonella marina, Heterosigma akashiwo, Cochlodinium polykriokides, and Heterocapsa circularisquama) and non-HABs (Chaetoceros simplex, Skeletonema sp. and Tetraselmis sp.), which is focused on the different population density and concentration gradients of algicidal substances. The time series viability of target alga was assessed based on the activity of Chl. a photosynthetic efficiency in terms of $F_v/F_m$, and in vivo fluorescence (FSU). Effective control of Raphidophyta, C. marina and H. akashiwo was achieved at a GreenTD concentration of $0.5{\mu}gL^{-1}$ and $0.2{\mu}gL^{-1}$, respectively, and regrowth of both the species was not observed even after 14 days. The inhibitory ratio of the dinoflagellate, C. polykriokides was more than 80% at $0.2{\mu}gL^{-1}$ of GreenTD. H. circularisquama was constantly affected in the presence of $0.2{\mu}gL^{-1}$ of GreenTD in the high- and low-population density experimental groups. On the other hand, diatoms, C. simplex, and Skeletonema sp. were not significantly affected even in the presence of $0.2{\mu}gL^{-1}$ of GreenTD and exhibited re-growth activity with the passage of incubation time. In particular, green alga Tetraselmis sp. remained unaffected even in the presence of the highest concentration of GreenTD ($1.0{\mu}gL^{-1}$), implying that non-HABs were not greatly influenced by the algicidal substances. As a result, the algicidal activity of GreenTD on the harmful and nonharmful algae was as follows: raphidophyte>dinoflagellates>diatoms>green alga. Consequently, our results indicate that inoculation of GreenTD substances into natural blooms at a threshold concentration ($0.2{\mu}gL^{-1}$) can maximize the algicidal activity against HABs species. If we consider the dilution and diffusion rate in the field application, it is hypothesized that GreenTD will demonstrate economic efficiency, thus leading to effective control against the target HABs in the closed bay.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.119-128
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• 2016

This study was conducted to develop temperature-driven models for a population model of turnip aphid, Lipaphis erysimi: nymphal development rate models and apterious adult's oviposition (larviparous) model. Nymphal development and the longevity and fecundity of adults were examined on cabbage at six constant temperatures (10, 15, 20, 25, 30, $35{\pm}1^{\circ}C$, 16L:8D). L. erysimi nymphs did not survive at $10^{\circ}C$. Development time of nymphs increased with increasing temperature up to $30^{\circ}C$ and thereafter slightly decreased, ranging from 18.5 d at $15^{\circ}C$ to 5.9 d at $30^{\circ}C$. The lower threshold temperature and thermal constant were estimated as $7.9^{\circ}C$ and 126.3 degree days, respectively. The nonlinear model of Lactin 2 fitted well for the relationship between the development rate and temperature of small (1+2 instar), large (3+4 instar) and total nymph (all instars). The Weibull function provided a good fit for the distribution of development times of each stage. Temperature affected the longevity and fecundity of L. erysimi. Adult longevity decreased as the temperature increased and ranged from 24.4 d at $20^{\circ}C$ to 16.4 d at $30.0^{\circ}C$ with abnormal longevity 18.2 d at $15^{\circ}C$, which was used to estimate adult aging rate model for the calculation of adult physiological age. L. erysimi showed a maximum fecundity of 91.6 eggs per female at $20^{\circ}C$. In this study, we provided three temperature-dependent components for an oviposition model of L. erysimi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate.

• The Journal of Korean Society for Radiation Therapy
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• v.28 no.1
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• pp.17-25
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• 2016

Purpose : The purpose of this study is to evaluate the variability of tumor motion and respiration pattern in lung cancer patients undergoing Stereotactic Body RadioTherapy(SBRT) by using On-Board imager (OBI) system and Real-time Position Management (RPM) System. Materials and Methods : This study population consisted of 60 lung cancer patient treated with stereotactic body radiotherapy (48 Gy / 4 fractions). Of these, 30 were treated with gating (group 1) and 30 without gating(group2): typically the patients whose tumors showed three-dimensional respiratory motion > 10 mm were selected for gating. 4-dimensional Computed Tomography (4DCT). Cone Beam CT (CBCT) and Fluoroscopy images were used to measure the tumor motion. RPM system was used to evaluate the variability of respiration pattern on SBRT for group1. Results : The mean difference of tumor motion among 4DCT, CBCT and Fluoroscopy images in the cranio-caudal direction was 2.3 mm in group 1, 2. The maximum difference was 12.5 mm in the group 1 and 8.5 mm in group 2. The number of treatment fractions that patient's respiration pattern was within Upper-Lower threshold on SBRT in group 2 was 31 fractions. A patient who exhibited the most unstable pattern exceeded 108 times in a fraction Conclusion : Although many patients in group 1 and 2 kept the reproducibility of tumor motion within 5 mm during their treatment, some patients exhibited variability of tumor motion in the CBCT and Fluoroscopy images. It was possible to improve the accuracy of dose delivery in SBRT without gating for lung cancer patient by using RPM system.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.281-289
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• 2004

The sex pheromone blend (28-12AC : E8-12AC : Z8-12OH = 95 : 5 : 1) of oriental fruit moth, Grapholita molesta (Busck), was evaluated with reference to its male attractivity at different dosage and lure longevity of 1.0 mg in a field condition. Also, degree-days (DD) were calculated up to major phenological events of G. molesta using seasonal adult flights monitored by pheromone traps and egg population densities in early season in Suwon peach orchards. In the range of 0.1-4.0 mg dosage examined, G. molesta males caught in pheromone trap decreased with increasing total pheromone doses. The highest number of G. molesta males were attracted in traps baited with 0.1 mg-lure, and there were no significantly differences among 0.5 to 4.0 mg-lure. In longevity test with a 1.0 mg-lure, there was no difference in mean numbers of G. molesta males caught between traps with fresh-baited lures every 20d and field-lasted lures up to ${\approx}50d$ after trap installation, but thereafter more G. molesta males were attracted in the field-lasted lures than in the fresh-baited lures. Accumulated degree-days (DD) from January 1 to the first adult emergence (biofix) were 39DD at a lower threshold temperature $8.1^{\circ}C$. Degree-days from the biofix up to the 1st adult peak through 4th peak were 98DD, 620DD, 1233DD, and 1916DD, respectively. Required degree-days from the 1st adult peak to the 1st egg peak were 130DD, while the 2nd egg peak timing was simultaneous with the 2nd adult peak. Further, management strategies of G. molesta were discussed in peach orchards.