Ha, Seung Man;Kim, Jeong Hoon;Oh, Seung Hun;Song, Ji Hwan;Kim, Hyoung Ihl;Shin, Dong Ah
Journal of Korean Neurosurgical Society
/
v.53
no.5
/
pp.288-292
/
2013
Objective : Vertebral distraction is routinely performed during anterior cervical discectomy and fusion (ACDF). Overdistraction can injure the facet joints and may cause postoperative neck pain consequently. The purpose of this study was to investigate the clinical relevance of distraction force during ACDF. Methods : This study included 24 consecutive patients with single level cervical disc disease undergoing single level ACDF. We measure the maximum torque just before the the arm of the Caspar retractor was suspended by the rachet mechanism by turning the lever on the movable arm using a torque meter. In order to turn the lever using the torque driver, we made a linear groove on the top of the lever. We compared the neck disability index (NDI) and visual analogue scale (VAS) scores between the high torque group (distraction force>6 $kgf{\cdot}cm$) and the low torque group (distraction force${\leq}6kgf{\cdot}cm$) at routine postoperative intervals of 1, 3, 5 days and 1, 3, 6 months. Results : The VAS scores for posterior neck pain had a linear correlation with torque at postoperative 1st and 3rd days ($y=0.99{\times}-1.1$, $r^2=0.82$; $y=0.77{\times}-0.63$, $r^2=0.73$, respectively). VAS scores for posterior neck pain were lower in the low torque group than in the high torque group on both 1 and 3 days postoperatively ($3.1{\pm}1.3$, $2.6{\pm}1.0$ compared with $6.0{\pm}0.6$, $4.9{\pm}0.8$, p<0.01). However, the difference in NDI scores was not statistically significant in all postoperative periods. Conclusion : Vertebral distraction may cause posterior neck pain in the immediate postoperative days. We recommend not to distract the intervertebral disc space excessively with a force of more than 6.0 $kgf{\cdot}cm$.
Kim, Yon-Soo;Chang, Kwon-Hee;Kim, Byung-Sik;Kim, Hung-Soo
Journal of Wetlands Research
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v.13
no.1
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pp.105-116
/
2011
Changes in climate have largely increased concentrated heavy rainfall, which in turn is causing enormous damages to humans and properties. Therefore, the exact relationship and the spatial variability analysis of hydrometeorological elements and characteristic factors is critical elements to reduce the uncertainty in rainfall -runoff model. In this study, radar rainfall grid resolution and grid resolution depending on the topographic factor in rainfall - runoff models were how to respond. In this study, semi-distribution of rainfall-runoff model using the model ModClark of Inje, Gangwon Naerin watershed was used as Gwangdeok RADAR data. The completed ModClark model was calibrated for use DEM of cell size of 30m, 150m, 250m, 350m was chosen for the application, and runoff simulated by the RADAR rainfall data of 500m, 1km, 2km, 5km, 10km from 14 to 17 on July, 2006. According to the resolution of each grid, in order to compare simulation results, the runoff hydrograph has been made and the runoff has also been simulated. As a result, it was highly runoff simulation if the cell size is DEM 30m~150m, RADAR rainfall 500m~2km for peak flow and runoff volume. In the statistical analysis results, if every DEM cell size are 500m and if RADAR rainfall cell size is 30m, relevance of model was higher. Result of sensitivity assessment, high index DEM give effect to result of distributed model. Recently, rainfall -runoff analysis is used lumped model to distributed model. So, this study is expected to make use of the efficiently decision criteria for configurated models.
Kim, Mi Sung;Kim, Byung Sook;Lee, Jong Sin;Oh, Gyung Jae;Han, Soung Hee
The Korean Journal of Food And Nutrition
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v.31
no.3
/
pp.425-434
/
2018
Metabolic syndrome is a risk factor for cardiovascular and type 2 diabetes. This study was conducted to examine the relevance between nutrition intake, meal quality, and high-sensitivity C-reactive protein in Koreans with metabolic syndrome. The 2,536 subjects, aged 19~64, who participated in 2015 National Nutrition Survey were included in this study. The 24-hour recall method was employed to analyze nutrition intake and dietary quality. Subjects were grouped into either the non-metabolic syndrome group (n=1,938) or the metabolic syndrome group (n=598). Total males and females were divided into 3 groups according to the high-sensitivity C-reactive protein (hs-CRP) level to study its relationship to metabolic syndrome and its components, including odds ratio (OR) and confidence interval (CI). Results showed the homeostasis model assessment of insulin resistance (HOMA-IR) value was higher in the metabolic syndrome group (3.37) than non-metabolic syndrome group (1.57) (p<0.001). In the Index of Nutrition Quality, males in the non-metabolic syndrome group showed higher niacin (p<0.05) than males in metabolic syndrome group. Females in the non-metabolic syndrome group had higher vitamin $B_1$ (p<0.01), vitamin $B_2$ (p<0.001), niacin (p<0.05), calcium (p<0.001), and phosphate (p<0.01). Female in the high hs-CRP group showed high OR in blood glucose component (OR 2.488, 95% CI: 1.269~4.879) and metabolic syndrome risk (OR 2.856, 95% CI: 1.292~6.314). Females in the middle hs-CRP group had high triglycerides component (OR 2.956, 95% CI: 1.920~4.551), compared to the low hs-CRP group. The study showed females with higher hs-CRP had a higher risk of metabolic syndrome.
Journal of the Korea Academia-Industrial cooperation Society
/
v.14
no.9
/
pp.4560-4571
/
2013
Current global issue of climate change is growing and greenhouse gases occur in most cities. To solve the problem of climate change, the city should be changed to low-carbon structure. Low-carbon city planning is a step-by-step plan from the initial establishment, from design and operation of urban structure, to maintenance and management should be considered as an integrated whole process. Under this background, this study evaluated the whole process of low-carbon urban planning ways. For this step, divided into three steps and eight divisions, 30 sub-indicators are derived. Through domestic and foreign cases analysis studies and survey of the relevant experts, results were derived. In order to improve these points, in the intial planning establishment stage, planning of urban policy and institutional steps should be made and the plan should be appropriate to the local characteristics. In the design and operation of urban structure stage, detailed and feasible approach is needed and maintenance and management stage, participation of various stakeholders, including establishing governance and management practices could see the need.
Lee, Jun Seok;Son, Dong Wuk;Lee, Su Hun;Ki, Sung Soon;Lee, Sang Weon;Song, Geun Sung;Woo, Joon Bum;Kim, Young Ha
Journal of Korean Neurosurgical Society
/
v.65
no.1
/
pp.96-106
/
2022
Objective : The most common complication of anterior cervical discectomy and fusion (ACDF) is cage subsidence and maintenance of disc height affects postoperative clinical outcomes. We considered cage subsidence as an inappropriate indicator for evaluating preservation of disc height. Thus, this study aimed to consider patients with complications such as reduced total disc height compared to that before surgery and evaluate the relevance of several factors before ACDF. Methods : We retrospectively reviewed the medical records of 40 patients who underwent stand-alone single-level ACDF using a polyetheretherketone (PEEK) cage at our institution between January 2012 and December 2018. Our study population comprised 19 male and 21 female patients aged 24-70 years. The minimum follow-up period was 1 year. Twenty-seven patients had preoperative bone mineral density (BMD) data on dual-energy X-ray absorptiometry. Clinical parameters included sex, age, body mass index, smoking history, and prior medical history. Radiologic parameters included the C2-7 cobb angle, segmental angle, sagittal vertical axis, disc height, and total intervertebral height (TIH) at the preoperative and postoperative periods. Cage decrement was defined as the reduction in TIH at the 6-month follow-up compared to preoperative TIH. To evaluate the bone quality, Hounsfield unit (HU) value was calculated in the axial and sagittal images of conventional computed tomography. Results : Lumbar BMD values and cervical HU values were significantly correlated (r=0.733, p<0.001). We divided the patients into two groups based on cage decrement, and 47.5% of the total patients were regarded as cage decrement. There were statistically significant differences in the parameters of measuring the HU value of the vertebra and intraoperative distraction between the two groups. Using these identified factors, we performed a receiver operating characteristic (ROC) curve analysis. Based on the ROC curve, the cut-off point was 530 at the HU value of the upper cortical and cancellous vertebrae (p=0.014; area under the curve [AUC], 0.727; sensitivity, 94.7%; specificity, 42.9%) and 22.41 at intraoperative distraction (p=0.017; AUC, 0.722; sensitivity, 85.7%; specificity, 57.9%). Using this value, we converted these parameters into a bifurcated variable and assessed the multinomial regression analysis to evaluate the risk factors for cage decrement in ACDF. Intraoperative distraction and HU value of the upper vertebral body were independent factors of postoperative subsidence. Conclusion : Insufficient intraoperative distraction and low HU value showed a strong relationship with postoperative intervertebral height reduction following single stand-alone PEEK cage ACDF.
This study was conducted to investigate the variables affecting the quality of life according to the degree of obesity of male and female college students. The research data used the data of the 8th year (2019) of the National Health and Nutrition Survey. Among the survey data, 287 students enrolled in college were enrolled. As a result of the study, the body mass index according to sex was 23.71kg/m2 for male students, 21.31kg/m2 for female students, and male students were overweight, and female students showed normal weight. The quality of life score according to gender was 0.97 points for male students and 0.98 points for female students, indicating a high quality of life score for female students. In the results of a regression analysis conducted to investigate the effect of obesity on the quality of life of college students, boys had normal weight (β=0.053, p=0.003), overweight (β=0.041, p=0.030) and obese weight compared to underweight. The quality of life was significantly higher in (β=0.046, p=0.012). However, there was no significant relevance in female students. In the future, it is considered that the education program for obese body type and the education program for underweight should be combined with the university's health-related education program.
Kim, Eunseop;Moon, Sun-In;Yim, Dong-Hyuk;Choi, Byung-Sun;Park, Jung-Duck;Eom, Sang-Yong;Kim, Yong-Dae;Kim, Heon
Journal of Environmental Health Sciences
/
v.48
no.4
/
pp.236-243
/
2022
Background: In the case of multiple exposures to different types of heavy metals, such as the conditions faced by residents living near a smelter, it would be preferable to group hazardous substances with similar characteristics rather than individually related substances and evaluate the effects of each group on the human body. Objectives: The purpose of this study is to evaluate the utility of factor analysis in the assessment of health effects caused by exposure to two or more hazardous substances with similar characteristics, such as in the case of residents living near a smelter. Methods: Heavy metal concentration data for 572 people living in the vicinity of the Janghang smelter area were grouped based on several subfactors according to their characteristics using factor analysis. Using these factor scores as an independent variable, multiple regression analysis was performed on health effect markers. Results: Through factor analysis, three subfactors were extracted. Factor 1 contained copper and zinc in serum and revealed a common characteristic of the enzyme co-factor in the human body. Factor 2 involved urinary cadmium and arsenic, which are harmful metals related to kidney damage. Factor 3 encompassed blood mercury and lead, which are classified as related to cardiovascular disease. As a result of multiple linear regression analysis, it was found that using the factor index derived through factor analysis as an independent variable is more advantageous in assessing the relevance to health effects than when analyzing the two heavy metals by including them in a single regression model. Conclusions: The results of this study suggest that regression analysis linked with factor analysis is a good alternative in that it can simultaneously identify the effects of heavy metals with similar properties while overcoming multicollinearity that may occur in environmental epidemiologic studies on exposure to various types of heavy metals.
The study was intended to explore the relevance of the variables below, assuming that the intolerance of uncertainty and dichotomous thinking would represent sequential serialized effects in the relationship between perfectionistic self-presentation and social anxiety. The data of this study were collected on questionnaire survey of 252 adult men and women in Seoul using perfectionistic self-presentation scale, social interaction anxiety scale, social phobia scale, intolerance of uncertainty scale and dichotomous thinkingI-30R as index, which results are as follow. First, intolerance of uncertainty and dichotomous thinking showed perfect mediation effects on the relationship between perfectionistic self-presentation and social anxiety. Intolerance of uncertainty and dichotomous thinking were identified as contributing factors to the development and preservation of social anxiety by perfectionistic self-presenters. Second, in the relationship between perfectionistic self-presentation and dichotomous thinking, intolerance of uncertainty showed mediation effect. And in the relationship between intolerance of uncertainty and social anxiety, dichotomous thinking showed mediation effect. This suggested that if tolerance of uncertainty was deficient, it was likely to lead to dichotomous thinking. And a dichotomous thinking has prompted or accelerated negative cognitive biases resulting from intolerance of uncertainty, triggering and deepening social anxiety. Lastly, the limitations of this study and future research direction were suggested.
Journal of the Korean Association of Geographic Information Studies
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v.26
no.4
/
pp.145-160
/
2023
The purpose of this study was to compare and analyze diurnal thermal environments using Unmanned Aerial Vehicles(UAV)-derived physical parameters(NDVI, SVF) and ENVI-met modeling. The research findings revealed significant correlations, with a significance level of 1%, between UAV-derived NDVI, SVF, and thermal environment elements such as S↑, S↓, L↓, L↑, Land Surface Temperature(LST), and Tmrt. In particular, NDVI showed a strong negative correlation with S↑, reaching a minimum of -0.52** at 12:00, and exhibited a positive correlation of 0.53** or higher with L↓ at all times. A significant negative correlation of -0.61** with LST was observed at 13:00, suggesting the high relevance of NDVI to long-wavelength radiation. Regarding SVF, the results showed a strong relationship with long-wave radiative flux, depending on the SVF range. These research findings offer an integrated approach to evaluating thermal comfort and microclimates in urban areas. Furthermore, they can be applied to understand the impact of urban design and landscape characteristics on pedestrian thermal comfort.
Dong Wook Kim;Hyemin Ahn;Kyung Won Kim;Seung Soo Lee;Hwa Jung Kim;Yousun Ko;Taeyong Park;Jeongjin Lee
Korean Journal of Radiology
/
v.23
no.11
/
pp.1055-1066
/
2022
Objective: The clinical relevance of myosteatosis has not been well evaluated in patients with pancreatic ductal adenocarcinoma (PDAC), although sarcopenia has been extensively researched. Therefore, we evaluated the prognostic value of muscle quality, including myosteatosis, in patients with resectable PDAC treated surgically. Materials and Methods: We retrospectively evaluated 347 patients with resectable PDAC who underwent curative surgery (mean age ± standard deviation, 63.6 ± 9.6 years; 202 male). Automatic muscle segmentation was performed on preoperative computed tomography (CT) images using an artificial intelligence program. A single axial image of the portal phase at the inferior endplate level of the L3 vertebra was used for analysis in each patient. Sarcopenia was evaluated using the skeletal muscle index, calculated as the skeletal muscle area (SMA) divided by the height squared. The mean SMA attenuation was used to evaluate myosteatosis. Diagnostic cutoff values for sarcopenia and myosteatosis were devised using the Contal and O'Quigley methods, and patients were classified according to normal (nMT), sarcopenic (sMT), myosteatotic (mMT), or combined (cMT) muscle quality types. Multivariable Cox regression analyses were conducted to assess the effects of muscle type on the overall survival (OS) and recurrence-free survival (RFS) after surgery. Results: Eighty-four (24.2%), 73 (21.0%), 75 (21.6%), and 115 (33.1%) patients were classified as having nMT, sMT, mMT, and cMT, respectively. Compared to nMT, mMT and cMT were significantly associated with poorer OS, with hazard ratios (HRs) of 1.49 (95% confidence interval, 1.00-2.22) and 1.68 (1.16-2.43), respectively, while sMT was not (HR of 1.40 [0.94-2.10]). Only mMT was significantly associated with poorer RFS, with an HR of 1.59 (1.07-2.35), while sMT and cMT were not. Conclusion: Myosteatosis was associated with poor OS and RFS in patients with resectable PDAC who underwent curative surgery.
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