• 한국지반공학회논문집
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• 제37권1호
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• pp.5-15
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• 2021

북극권과 같은 한대지역의 동상민감성 지반은 계절적 대기 온도 변화 및 설치된 구조물의 온도에 의해 지반의 융기 및 침하 문제가 존재한다. 이러한 동상민감성 지반의 융기 및 침하 방지를 위한 지반안정화 공법으로는 매립 및 치환공법, 열 사이펀 등이 존재한다. 여기서 열 사이펀이란 내부 냉매의 증발, 응축을 반복하며 열 순환을 통해 이상 유동(two-phase flow)의 형태로 냉매가 지반의 온도를 외부로 전달하여 지반 온도를 조절 할 수 있는 공법이다. 본 연구는 이러한 열 사이펀의 성능을 열전도율로 수치화하기 위하여 ABAQUS 내부의 User-subroutine 코딩을 통해 열 사이펀을 지중의 한 열원으로 간주, 경계조건으로 적용시켜 기존 문헌의 열 사이펀 실내모형실험의 온도분포 결과와 비교하여 산정하였다.

• Korean Circulation Journal
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• 제53권2호
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• pp.69-91
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• 2023

Cardio-oncology is an emerging multi-disciplinary field, which aims to reduce morbidity and mortality of cancer patients by preventing and managing cancer treatment-related cardiovascular toxicities. With the exponential growth in cancer and cardiovascular diseases in Asia, there is an emerging need for cardio-oncology awareness among physicians and country-specific cardio-oncology initiatives. In this state-of-the-art review, we sought to describe the burden of cancer and cardiovascular disease in Asia, a region with rich cultural and socio-economic diversity. From describing the uniqueness and challenges (such as socio-economic disparity, ethnical and racial diversity, and limited training opportunities) in establishing cardio-oncology in Asia, and outlining ways to overcome any barriers, this article aims to help advance the field of cardio-oncology in Asia.

• Korean Circulation Journal
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• 제53권10호
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• pp.655-676
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• 2023

Interest in sex differences in coronary artery disease (CAD) has been steadily increasing. Concurrently, most of the data on these differences have primarily been Western-oriented. The KoRean wOmen'S chest pain rEgistry (KoROSE), started in 2011, has since published numerous research findings. This review aims to summarize the reported differences between men and women in CAD, integrating data from KoROSE. Cardiovascular risk in postmenopausal women escalates dramatically due to the decrease in estrogen levels, which normally offer cardiovascular protective effects. Lower estrogen levels can lead to abdominal obesity, insulin resistance, increased blood pressure, and endothelial dysfunction in older women. Upon analyzing patients with CAD, women are typically older and exhibit more cardiovascular risk factors than men. Diagnosing CAD in women tends to be delayed due to their symptoms being more atypical than men's. While in-hospital outcome was similar between sexes, bleeding complications after percutaneous coronary intervention occur more frequently in women. The differences in long-term prognosis for CAD patients between men and women are still a subject of ongoing debate. Pregnancy and reproductive factors also play a significant role as risk factors for cardiovascular disease in women. A notable sex disparity exists, with women found to use fewer cardiovascular protective drugs and undergo fewer interventional or surgical procedures than men. Additionally, women participate less frequently than men in clinical research. Through concerted efforts to increase awareness of sex differences and mitigate sex disparity, personalized treatment can be provided. This approach can ultimately improve patient prognosis.

• Korean Circulation Journal
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• 제54권3호
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• pp.113-123
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• 2024

Background and Objectives: Previous studies have reported an association between impaired renal function and poor outcomes after radiofrequency catheter ablation in patients with atrial fibrillation (AF). However, outcomes of cryoballoon ablation (CBA) in patients with renal insufficiency are not fully elucidated. This study aimed to compare outcomes of CBA in AF patients with chronic kidney disease (CKD) versus those without CKD and to assess changes in renal function over 12 months following CBA. Methods: A total of 839 patients (65.1% with non-paroxysmal AF [PAF]) who underwent de novo CBA were prospectively enrolled. We divided patients into two groups based on creatinine clearance rate (CCr) and performed intracardiac echocardiography (ICE)-guided contrast agent-free CBA. Results: In comparison with patients without CKD (CCr >50, n=722), those with CKD (CCr ≤50, n=117) were older and predominantly female, had a lower body mass index, and showed a higher prevalence of heart failure and hypertension. Mean CHA₂DS₂-VAS score was significantly higher in CKD group than in non-CKD group. Procedure-related complications were not significantly different between two groups. During a mean follow-up period of 25.4±11.9 months, clinical recurrence occurred in 182 patients (21.7%) and not significantly different between two groups. In multivariate analysis, non-PAF and left atrial size were independent predictors of AF recurrence. CCr levels significantly improved over 12 months after CBA in CKD group. Conclusions: ICE-guided contrast-agent-free CBA showed comparable long-term clinical outcomes without increasing procedure-related complications and improvement of renal function over 12 months following CBA in AF patients with CKD.

• Korean Circulation Journal
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• 제52권11호
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• pp.829-843
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• 2022

Background and Objectives: Despite remarkable reduction in cardiovascular disease (CVD) mortality, the burden has remained the leading cause of death. Since little research has focused on regional disparity in CVD mortality, this study aims to investigate its spatiotemporal trends in Korea from 1983 to 2019. Methods: Using the causes of death statistics in Korea, we analyzed the geographic variation in deaths from CVDs from 1983 to 2019. The sex and age-standardized mortality rate was calculated according to the 17 administrative regions. The analyses include all diseases of the circulatory system (International Classification of Diseases-10 codes, I00-I99), along with the following 6 subcategories which were not mutually exclusive: total heart disease (I00-I13 and I20-I51), hypertensive heart disease (I10-I13), ischemic heart disease (I20-I25), myocardial infarction (I21-I23), heart failure (I50), and cerebrovascular disease (I60-I69). Results: Overall, heart failure death rate increased across all regions, and other CVD death rates showed a decreasing trend. Regional disparity in mortality was substantial in the early 1980s but converged over time. In all types of cardiovascular mortality, Busan, Ulsan and Gyeongnam remained the highest, although they showed a downward trend like other regions. Jeju continued to have a relatively low CVD mortality rate. Conclusions: The regional disparity substantially decreased compared to the 1980s. However, the relatively high burden of CVD mortality in the southeastern region has not been fully resolved.

• Korean Circulation Journal
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• 제52권10호
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• pp.755-767
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• 2022

Background and Objectives: Cryoballoon catheter ablation for the treatment of patients with symptomatic atrial fibrillation (AF) has been adopted globally, but there are limited multicenter reports of 12-month outcomes in the Korean patient population. This analysis evaluated the clinical performance and safety of cryoballoon ablation (CBA) according to standard-of-care practices in Korea. Methods: This evaluation of Korean patients with AF was conducted within the larger Cryo Global Registry, which is a prospective, multicenter, post-market registry. Freedom from a ≥30-second recurrence of atrial arrhythmias (after a 90-day blanking period until 12 months) and procedural safety were examined in subjects treated with CBA at 3 Korean centers. Results: Overall, 299 patients with AF (60±11 years old, 24.7% female, 50.5% paroxysmal AF) underwent CBA using the Arctic Front Advance cryoballoon. Of those, 298 were followed-up for at least 12 months. Mean procedure-, left atrial dwell- and fluoroscopy time was 76±21 minutes, 56±23 minutes, and 27±23 minutes, respectively. Freedom from AF recurrence at 12 months was 83.9% (95% confidence interval [CI], 76.9-88.9%) in the paroxysmal and 61.6% (95% CI, 53.1-69.0%) in the persistent AF cohort. Rhythm monitoring was performed on average 4.7±1.4 times during the follow-up period. Serious device- or procedure-related adverse events occurred in 2 patients (0.7%). The 12-month Kaplan-Meier estimate of freedom from repeat ablation and cardiovascular-related hospitalization was 93.8% (95% CI, 90.4-96.1%) and 89.7% (95% CI, 85.6-92.7%), respectively. Conclusions: CBA is an efficient, effective, and safe procedure for the treatment of AF patients when used according to real-world practices in Korea.

• Korean Circulation Journal
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• 제54권1호
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• pp.1-12
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• 2024

Background and Objectives: The objective of this study was to estimate the supply and demand for cardiologists in Korea and provide evidence for healthcare policy to ensure a stable and adequate workforce for optimal cardiovascular disease management. Methods: Past trends of inflow and outflow of cardiologists were used to make crude projections, which were then adjusted based on demands of services to obtain final projections. Inflow of cardiologists was estimated using second-order polynomial regression and demand for cardiology care was estimated using linear regression. Results: There were 1,139 active cardiologists who were under the age of 65 in clinical practice in Korea. The estimated number of cardiologists from 2022 to 2040 showed that the number of cardiologists would peak at 1,344 in 2032 and gradually decrease thereafter. We also estimated an increase of 947,811 cases of heart-related procedures annually from 2023 to 2032. The number of heart-related procedures per cardiologist would increase 1.4 times from 12,964 in 2023 to 17,862 in 2032. The estimated number of emergency patients per cardiologist under 50 years old would almost double from 544 in 2022 to 987 in 2032. Conclusions: We expect significant shortage of cardiologists in Korea within the next 10 years. The number of emergency patients per cardiologist will increase by nearly 50%, leading to high individual workload for cardiologists. To prevent this imbalance between supply and demand, an organized and collective approach by the specialty of cardiology is imperative to produce a balanced workforce.

• Korean Circulation Journal
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• 제54권5호
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• pp.270-287
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• 2024

Background and Objectives: Blood pressure (BP) measurement using an auscultatory sphygmomanometer is recommended for diagnosing hypertension in children. As mercury sphygmomanometers (MSs) are banned owing to environmental concerns, it is crucial to determine the accuracy of mercury-free sphygmomanometers to replace them. We analyzed the accuracy of these devices to guide the National Survey selection. Methods: BP was measured thrice each with MS, auscultatory device (AD), and oscillometric device (OD) in 104 participants aged 10-18 using the National Survey data. The difference in BP was defined as the difference between MS and other devices. The BP differences, correlations, and influencing factors were analyzed. The frequencies of hypertension were also compared. Results: Systolic BP (SBP) and diastolic BP (DBP) differences between MS and AD were 0.88±3.36 mmHg and 0.63±3.95 mmHg, and those between MS and OD were 0.43±5.83 mmHg and 4.57±6.89 mmHg, respectively. The absolute error of <10 mmHg for DBP between MS and OD was 76%. The concordance correlation coefficient between MS and AD was 0.94 for SBP and 0.90 for DBP, and 0.81 and 0.67, respectively for MS and OD. Arm circumference negatively correlated with BP differences except for SBP between the MS and OD. The frequency of hypertension was not different between MS and AD but was underestimated by OD. Conclusions: AD correlated well with MS, while OD did not, especially for DBP. The superiority of AD over OD suggests AD as a possible alternative for MS in the National Survey.

• 한방안이비인후피부과학회지
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• 제19권2호
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• pp.130-145
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• 2006

Objectives : The aim of this work is the approaching of properties-flavours theory and the making of morphological standard in Artemisiae herba. Methods : The properties-flavours theory were attempted with bibliographic method and various climate-information. The external-internal morphological standards were determined by using stereoscope and butanol series. Conclusions : The following is a list the conclusion of the approaching of properties-flavours theory and how to make the standard of morphological standard in artemisiae herba. 1. The significant analysis for the artemisiae herba as the properties-flavours theory, is a follow-up survey of the effect written in the official oriental medicine book 2. The other analytic methods according to the gathering time, processing or storing system or especially nature or growth environment(altitude, temperature,. the mean moisture, and the agronomical survey) by way of the explanation of properties-flavours theory appears so many insufficiency at the many cases. 3. In the case of artemisiae herba., there are 2 cases(Artemisia capillaris $T_{HUNB}$ and A. iwayomogi $K_{ITAMURA}$) in current and recently A. aruwa L. is substituted for artemisiae herba in circulation. 4. The external and internal characteristics according to the shape of original plant or herbal states, entirely correspond to all the official oriental medicine boo 5. According to the place of productiot the difference appeals. (1) A. capillatis $T_{HUNB}$. has leaves like a fine thread, and A. iwayomogi $K_{ITAMURA}$ has big and wide leaves, and shows some reddish color, and A. aruwa L. has narrow leaves, its section lines long vertically. (2) In the internal shapes, as the A. capillatis $T_{HUNB}$. leaves', upper epidermal cell wall shows relatively straight form, its all upper- lower epidemical cell wall has a stoma, and calcium rosette crystal is relatively few. As iwayomogi $K_{ITAMURA}$, all upper- lower epidermal cell wall is wavelike concave, and hypodermics has many stoma and many calcium rosette crystal. (3) In the internal shapes of A. aruwa L. the shape of leaves' epidermal cell is irregular and has so many non-glandular hair nad glandular hair on its surface.

• 동의생리병리학회지
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• 제23권6호
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• pp.1247-1260
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• 2009

This dissertation aims to study the five tastes in the Yellow Emperor's Canon of Internal Medicine. Medicinals as well as Foods are classified by the five tastes: sweet, sour, bitter, salty and pungent, which can be tasted by the tongue. With the development of the theory dealing with the medicinal properties, some flavors are summarized out of clinical actions of medicinals, therefore, there is a little difference between the flavors of medicinal herbs and the tastes got by tongue. Each taste acts on or has direct influence on a specific vital organ, and each of which has different physiologic actions. Taste also has a long-term or post digestive effect on the body and its metabolism. When each taste is consumed in moderation, it benefits the corresponding organ. Over-indulgence in any taste harms the organ and creates imbalance among the five vital organ systems. The Korean medicinal herbs with same flavor mostly possess similar actions while the medicinal herbs with different flavors show different actions in the treatment, which are shown as follows. Sour has absorbing, consolidating and astringent actions and acts on the liver. Bitter has the actions of drying or resolving dampness, purging and lowering and acts on the heart. Sweet has the nourishing, harmonizing and moistening actions and acts on the spleen. Pungent has an action of dispersing and promoting circulation of gi and blood and acts on the lungs. Salty has the effects of softening hard nodes or masses and promoting defecation, etc and acts on the kidneys. The five organ systems control and support each other. Proper coordination only exists when there is no one organ stronger or weaker than the rest. Since the five tastes have direct influences on the five organs, the diet we take should have a good combination of the five tastes in order to promote internal balance and harmony. They control our well-being and create dietary balance. Excessive consumption of any of these could result in adverse effects. In a word, when the properties of the five tastes respectively are distinguished, their natures and flavors cannot be separately considered. I think the harmonization of food and medicinals should be stressed on good nutritional diet to maintain good health. The traditional belief that food and medicine share the same origin is a part of Korean medicine tradition.