• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.215-231
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• 2020

Forest landscape models (FLMs) can be used to investigate the complex interactions of various ecological processes and patterns, which makes them useful tools to evaluate how environmental and anthropogenic variables can influence forest ecosystems. However, due to the large spatio-temporal scales in FLMs studies, parameterization and validation can be extremely challenging when applying to new study areas. To address this issue, we focused on the parameterization and application of a spatially explicit forest landscape model, LANDIS-II, to Mt. Gyebang, South Korea, with the use of the National Forest Inventory (NFI) and long-term ecological research (LTER) site data. In this study, we present the followings for the biomass succession extension of LANDIS-II: 1) species-specific and spatial parameters estimation for the biomass succession extension of LANDIS-II, 2) calibration, and 3) application and validation for Mt. Gyebang. For the biomass succession extension, we selected 14 tree species, and parameterized ecoregion map, initial community map, species growth characteristics. We produced ecoregion map using elevation, aspect, and topographic wetness index based on digital elevation model. Initial community map was produced based on NFI and sub-alpine survey data. Tree species growth parameters, such as aboveground net primary production and maximum aboveground biomass, were estimated from PnET-II model based on species physiological factors and environmental variables. Literature data were used to estimate species physiological factors, such as FolN, SLWmax, HalfSat, growing temperature, and shade tolerance. For calibration and validation purposes, we compared species-specific aboveground biomass of model outputs and NFI and sub-alpine survey data and calculated coefficient of determination (R²) and root mean square error (RMSE). The final model performed very well, with 0. 98 R² and 8. 9 RMSE. This study can serve as a foundation for the use of FLMs to other applications such as comparing alternative forest management scenarios and natural disturbance effects.

• Journal of Hospice and Palliative Care
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• v.18 no.4
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• pp.314-321
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• 2015

Purpose: It is well known that a terminal cancer condition affects not only patient themselves but their family members because the patients experience a variety of symptoms. This study was aimed to investigate modifiable factors that influence family caregivers' quality of life, depression, and anxiety. Methods: From January 2015 through May 2015, a survey was conducted with 61 family caregivers of hospice patients who were hospitalized in two university hospitals and one municipal hospital in Busan. The questionnaire was consisted of characteristics of family caregivers and patients, the Korean version of the Caregiver Quality of Life Index-Cancer (CQOLC-K), Beck's Depression Inventory II (BDI-II), Beck's Anxiety Inventory (BAI), and patient's symptom controlling scores rated by family caregivers. Results: Family caregivers' depression was associated with religion. Quality of life and depression of family caregivers were also influenced by monthly household income. Patient age was inversely related to family caregiver's quality of life ($r_s=-0.259$, P=0.043). Family caregivers' quality of life was associated with patient's anxiety (r=0.443, P=0.001). Family caregivers' depression was affected by patient's constipation (r=0.276, P=0.046), anxiety (r=0.508, P<0.001), and daytime drowsiness (r=0.377, P=0.005). And family caregivers' anxiety was influenced by patients' sleep disturbance (r=0.276, P=0.046), depression (r=0.297, P=0.031), and anxiety (r=0.357, P=0.009). Conclusion: According to our findings, family caregivers had higher quality of life and less depression and anxiety when symptoms in hospice patients were well controlled.

• Sleep Medicine and Psychophysiology
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• v.3 no.1
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• pp.85-95
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• 1996

Obstructive sleep apnea syndrome(OSAS) in childhood is unique and different n-om that in adulthood in several aspects, including pathophysiology, clinical features, diagnostic criteria, complications, management, and prognosis. Characteristic features of childhood OSAS in comparison with the adult form are the variety of severe complications such as developmental delay, more prominent behavioral and cognitive impairments, vivid cardiovascular symptoms, and increased death risk, warranting a special attention to the possible diagnosis of OSAS in children who snore. However, the childhood OSAS is often neglected and unrecognized. We, therefore, report a case of very severe OSAS in a 5-year-old boy who was sucessfully treated with continuous positive airway pressure(CPAP) treatment. Interestingly, the patient was comor-bid with the attention deficit hyperactivity disorder. Prior to the initial visit to us, adenotonsillectomy had been done at the age of 4 with no significant improvement of apneic symptoms and heavy snoring. On the initial diagnostic procedures, marked degree of snoring was audible even in the daytime wake state and the patient was observed to be very hyperactive. Increased pulmonary vascularity with borderline cardiomegaly was noted on chest X-ray. The baseline polysomnography revealed that the patient was very sleep-apneic and snored very heavily, with the respiratory disturbance index(RDI) of 46.9 per hour of sleep, the mean SaO2 of 78.8%, and the lowest SaO2 of 40.0%(the lowest detectable oxygen level by the applied oxymeter). The second night polysomnography was done for CPAP titration and the optimal pressure turned out to be $8.0\;cmH_2O$. The applied CPAP treatment was well tolerated by the patient and was found to be very effective in alleviating heavy snoring and severe repetitive sleep apneas. After 18 months of the CPAP treatment, the patient was followed up with nocturnal polysomnography(baseline and CPAP nights) and clinical examination. Sleep apneas were still present without CPAP on the baseline night. However, the severity of OSAS was significantly decreased(RDI of 15.7, mean SaO2 of 96.2%, and the lowest SaO2 of 83.0%), compared to the initial polysomnographic findings before initiation of long-term CPAP treatment. Wechsler intelligence tests done before and after the CPAP treatment were compared with each other and surprising improvement of intelligence(total 9 points, performance 16 points) was noted. Clinically he was found to be markedly improved in his attention deficit hyperactive behavior after CPAP treatment, but with minimal change of TOVA(test of variables of attention) scores except conversion of reaction time score into normal range. On the chest X-ray taken after 18 months of CPAP application, the initial cardiopulmonary abnormalities were not found at all. We found that the CPAP treatment in a young child is very effective, safe, and well-tolerated and also improves the co-morbid attention deficit hyperactive symptoms. Overall, the growth and development of the child has been facilitated with the long-term use of CPAP. Cardiovascular complications induced by OSAS have been also normalized with CPAP treatment. We suggest that early diagnosis and active treatment intervention of OSAS in children are crucial in preventing and ameliorating possible serious complications caused by repetitive sleep apneas and consequent hypoxic damage during sleep.

• Sleep Medicine and Psychophysiology
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• v.6 no.1
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• pp.76-84
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• 1999

Objectives: A number of studies have shown that sleep deprivation results in reduced vigilance and increased negative affects such as tension, depression and anger. However there are few studies about effects of sleep deprivation on anxiety. The purpose of this study was to investigate the effects of 40 hour sleep deprivation on state anxiety, affects, sleepiness and fatigue. The authors also intended to study the effect of trait-anxiety on these psychological variables after sleep deprivation. Methods: Twenty nine subjects(22 men, 7 women, $24.59{\pm}1.35$ years of age) participated in this study. Subjects had no past history of psychiatric disorders and physical illnesses, and had normal sleep-waking cycle without current sleep disturbances. All of the subjects completed sleep dairy for two weeks to exclude some who suffered from chronic sleep deprivation or sleep disturbances. Subjects were instructed to get a normal sleep as usual at night before the study. After awakening, subjects remained awake for 40 hours under continuous surveillance. They completed State-Trait Anxiety Inventory, Index of General Affect, Stanford Sleepiness Scale and Fatigue Questionnaire every three hours, therefore they completed the scales 14 times totally. Subjects were dictated not to take caffeine, alcohol, or any medications on the day of the study. Heavy exercises and naps were restricted too. Results: Sleep deprivation resulted in increased state anxiety, negative general affects, and increased sleepiness and fatigue(p<.001). Dividing into high trait-anxiety group and low trait-anxiety group, there was significant sleep deprivation x traitanxiety interaction effect on general affect(p<.05). But, there was no significant sleep deprivation x trait-anxiety interaction effect on state-anxiety, sleepiness and fatigue. During sleep deprivation, the highest ratings of scales on anxiety, negative affect, sleepiness and fatigue occurred between 4 : 00AM and 7 : 00AM. Conclusions: These results show that sleep deprivation results in increased anxiety, mood state disturbance and increment of sleepiness and fatigue. These findings also suggest that trait-anxiety is a factor that influences the degree of worsening in general affect caused by sleep deprivation. During sleep deprivation, the rating curves of anxiety, affect, sleepiness and fatigue show rhythmicity that may be related to circadian rhythm.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.252-265
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• 2017

This study aims to analyze the landscape ecological characteristics of green spaces within built up area of high density and evaluate the potential applicability of green patches, thereby introducing urban garden for generating green networks in residence areas. To this end, Yeoksam-Dong was selected as the site area since it is classified as both green initiative zone and alienated area of park service in Seoul. First, the current condition of green spaces in Yeoksam-Dong was identified by five categories: Street trees, private garden, public pocket garden, rooftop garden, and park. Then, the landscape index analysis through FRAGSTATS and connectivity assessment via multi-buffer zone analysis were carried out for analyzing the green networks and evaluating the potential value of green space. The results showed that the degree to which green areas in the site were distributed is arranged in the order of street tree, private garden, public pocket garden, park, and rooftop garden. In case of the street trees whose total core area (TCA, $1,618m^2$) is as high as the park's ($1,128m^2$). Private garden has potential for green network in built up area of high density by gardening since the shape of the patches are irregular (ED = 78.1m/ha) and the average distance among the patches is close (ENN=33.9m). Public pocket garden has also potential for gardening according to the result that it was found to be distributed evenly (LPI=5.7%, SHEI=0.9) with exposing external disturbance ($TCA=66m^2$). For the green network, 84% of all the study site is covered by small green network in 50m butter range of connected green area. The effect of green network was expected through gardening in public pocket garden (27%) and street tree (26%). Accordingly, it is encouraged to actively utilize street tree, private gardens, and rooftop gardens and to establish the urban gardens like local-based community gardens in public pocket garden where a variety of activities can be carried out near residential areas. By doing so, green networks can effectively be established in built up area with high density. The results of this study can contribute positively to fostering the creation of various types of urban gardens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1395-1404
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• 2013

The purpose of this study was to evaluate the diet quality in Korean middle-aged women based on their self-rated health status (SRH) as well as to investigate the relationship between SRH and the diet quality. For the study, we obtained data for analysis from the combined 2008~2009 Korean National Health and Nutrition Examination Survey (KNHANES). The study subjects were divided into two groups-'Good' group (${\geq}3.06$, n=622) and 'Bad' group (<3.06, n=1,092)- on the basis of the average SRH value (3.06). The women in the 'Good' group had achieved a higher education level and had a significantly high monthly average income (P<0.05), whereas women in the 'Bad' group had a larger waist circumference (P<0.05). In addition, women in the 'Good' group engaged in more physical activities (P<0.01). In comparison with the women in 'Bad' group, women in the 'Good' group were found to have a superior nutritional status, with a nutrient adequacy ratio (NAR) of protein (P<0.05), calcium (P<0.05), iron (P<0.05), vitamin A (P<0.05), vitamin $B_2$ (P<0.05), and niacin (P<0.01). The mean adequacy ratio (MAR) of women in the 'Good' group was also significantly higher than that of the women in the 'Bad' group. The index of nutritional quality (INQ) of protein (P<0.05), iron (P<0.05), vitamin $B_1$ (P<0.05), and niacin (P<0.05) in women belonging to the 'Good' group were also significantly higher than that in the women assigned the 'Bad' group. The results of regression analysis on the relevance between the diet quality and SRH, MAR, and INQ showed a significantly positive relevance (P<0.001), even after adjusting for disturbance factors. The results of this study show that diet quality seems to be the important factor for improving SRH of women. Therefore, we suggest that developing dietary guidelines and educating women about the guidelines would improve health of middle-aged women in Korea.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.3
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• pp.100-114
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• 2018

Nationally designated Cultural Properties 'Scenic site No.12 Maisan Mountain, Jinan' designated areas and some protected areas, and taking into account the dynamics of naturalized plants causing problems, we will restore the original vegetation scenery of Mt. Maisan. The results of this study are as follows. A total of 76 families, 192 genera, 286 taxa, and inland and inhabited areas, 76 and 138 genera and 163 taxa were identified in the areas of Ammaibong. The total number of naturalized plants identified in this study area is 28 taxa total, which corresponds to 7.1% naturalization rate(NR) among the vascular plants of all 395 taxa, and the urbanization index(UI) corresponds to 8.4% of the 333 taxa of Korean naturalized plants. Ecosystem disturbance plants identified in the survey area were Ambrosia artemisiifolia 1 taxa. The naturalized plants controlled and managed by separate anthropogenic vegetation management within the designation and protection area of Maisan scenic place are three species of herbaceous Rumex acetosella, A. artemisiifolia and Festuca arundinacea. It was identified as a breed. Indigofera bungeana and F. arundinacea communities around the stairway and Amorpha fruticosa, I. bungeana, A. artemisiifolia and Amaranthus patulus of the top of Am-Maibong were selected as the first priority sites for exclusion of exotic species in Maisan area and target naturalized plants species to the Ammaibong peak. In addition, R. acetosella community around the temple was suggested to be removed first to preserve endemic species. For the restoration of vegetation, we suggest that Stephanandra incisa, Spiraea blumei, Weigela subsessilis, etc. should be planted after removal of I. bungeana, and F. arundinacea, C. lanceolata, Carex callitrichos var. nana.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.198-221
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• 2021

After large-scale reforestation in the 1960s and 1970s, forests in Korea have gradually been aging. Net ecosystem CO₂ exchange of old-growth forests is theoretically near zero; however, it can be a CO₂ sink or source depending on the intervention of disturbance or management. In this study, we report the CO₂ budget dynamics of the Gwangneung deciduous old-growth forest (GDK) in Korea and examined the following two questions: (1) is the preserved GDK indeed CO₂ neutral as theoretically known? and (2) can we explain the dynamics of CO₂ budget by the common mechanisms reported in the literature? To answer, we analyzed the 15-year long CO₂ flux data measured by eddy covariance technique along with other biometeorological data at the KoFlux GDK site from 2006 to 2020. The results showed that (1) GDK switched back-and-forth between sink and source of CO₂ but averaged to be a week CO₂ source (and turning to a moderate CO₂ source for the recent five years) and (2) the interannual variability of solar radiation, growing season length, and leaf area index showed a positive correlation with that of gross primary production (GPP) (R²=0.32~0.45); whereas the interannual variability of both air and surface temperature was not significantly correlated with that of ecosystem respiration (RE). Furthermore, the machine learning-based model trained using the dataset of early monitoring period (first 10 years) failed to reproduce the observed interannual variations of GPP and RE for the recent five years. Biomass data analysis suggests that carbon emissions from coarse woody debris may have contributed partly to the conversion to a moderate CO₂ source. To properly understand and interpret the long-term CO₂ budget dynamics of GDK, new framework of analysis and modeling based on complex systems science is needed. Also, it is important to maintain the flux monitoring and data quality along with the monitoring of coarse woody debris and disturbances.

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.165-176
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• 2022

This study surveyed the characteristics of fish communities in Hwapocheon Wetland, Korea, from May to September 2020. The survey collected 735 objects in 21 species belonging to 7 families from 8 survey stations. The dominant and subdominant species were Hemiculter eigenmanni(23.8%) and Micropterus salmoides(10.3%), respectively. The next most abundant species were Zacco platypus(9.5%), Carassius auratus(9.4%), Pseudorasbora parva(9.0%), Squalidus chankaensis tsuchigae(6.7%), Acheilognathus macropterus(5.4%), Lepomis macrochirus(5.2%), Pseudogobio esocinus(4.1%), Opsariichthys uncirostris amurensis(3.7%), and Carassius cuvieri(3.3%). Among the fish species collected, one species, Culter brevicauda, was class II endangered wildlife designated by the Ministry of Environment, and one species,S. c. tsuchigae(4.8%), was endemic to Korea.Additionally, three exotic species (M. salmoides, L. macrochirus, and C. cuvieri) and one landlocked species (Rhinogobius brunneus) were collected. Compared to previous studies, the proportion of fish living in the running water area tended to decrease, the proportion of fish living in the water purification area tended to increase, and ecosystem-disturbing species (M. salmoides and L. macrochirus) tended to increase gradually. Results of fish community analysis showed that the mainstream stations (St. 1, 3, 4, 5, 6, and 8) had low dominance, but high diversity and richness, and other stations (St. 2 and 7) had high dominance but low diversity and richness. The river health (index of biological integrity) evaluated using fish was assessed as bad (6 stations), normal (1 station), and very bad (1 station). The water quality grade was assessed as slightly bad due to the chemical oxygen demand (COD), total organic content (TOC), suspended solid (SS), and total coliforms (TC). The annual water quality showed a gradually increasing trend of biological oxygen demand (BOD), COD, SS, and chlorophyll-a. The stable life of fish and the improvement of river health in Hwapocheon Wetland require water quality improvement and the systematic management of ecosystem-disturbing species (M. salmoidesand L. macrochirus).

• Korean Journal of Ecology and Environment
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• v.55 no.3
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• pp.231-243
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• 2022

Anthropogenic disturbances on freshwater ecosystem are known to degrade biodiversity, especially on fish assemblage. In this study, we have conducted fish surveys to identify impact of a bridge construction on fish assemblages. A total of eight study sites were surveyed in the Danjang and the Dong Stream in southern part of South Korea from June to November in 2021. The fish samplings were carried out five times, using cast-nets(10×10 mm mesh size), scoop-nets(4×4 mm, 5×5 mm mesh size), set-nets (10×10 mm mesh size), and fish traps (3×3 mm mesh size), along with the Stream/River Ecosystem Survey and Health Assessment by the Ministry of Environment of Korea and basic water quality measurement. Also, we applied the species diversity index and length-weight relationship regressions on certain species to identify interspecific growth rate differences in accordance with study sites. As a result, a total of 782 individuals, 23 species and 10 families were collected. The dominant species was Zacco Koreanus and relative abundance was 50.89%. When applying the length-weight relationship regressions on certain species, the 'b' value for Z. Koreanus was lower at the downstream points than at the upstream points of the construction site. In addition, when comparing to the results of the past survey, relative density of demersal fish at the upstream and downstream points decreased from 26% to 1.4%, and from 18% to 6.3%, respectively. In conclusion, it is considered that bridge construction negatively affects the habitat of fishes, especially on demersal fishes. Therefore, appropriate conservation efforts such as installation of silt protector and sand sedimentation pond are needed to alleviate the disturbance in habitat such as occurrence of turbidity and destruction of micro-habitats.