Effect of Total Hip Arthroplasty on Ipsilateral Lower Limb Alignment and Knee Joint Space Width: Minimum 5-Year Follow-up

Choi Yun Seong,Park Jung-Wee,Kim Tae Woo,Kang Kee Soo,Lee Young-Kyun,Koo Kyung-Hoi,Chang Chong Bum 대한의학회 2023 Journal of Korean medical science Vol.38 No.20

Background: This study aimed to 1) assess the effect of total hip arthroplasty (THA) on coronal limb alignment, namely, the hip–knee–ankle angle (HKA), 2) identify factors that determine changes in the HKA, and 3) determine whether alignment changes influence the knee joint space width. Methods: We retrospectively evaluated 266 limbs of patients who underwent THA. Three types of prostheses with neck shaft angles (NSAs) of 132°, 135°, and 138° were used. Several radiographic parameters were measured in the preoperative and final radiographs (at least 5 years after THA). A paired t-test was used to confirm the effect of THA on HKA change. Multiple regression analysis was performed to identify radiographic parameters related to HKA changes following THA and changes in knee joint space width. Subgroup analyses were performed to reveal the effect of NSA change on the HKA change, and the proportion of total knee arthroplasty usage and changes in radiographic parameters between maintained joint space and narrowed joint space groups were compared. Results: The preoperative mean HKA was 1.4° varus and increased to 2.7° varus after THA. This change was related to changes in the NSA, lateral distal femoral angle, and femoral bowing angle. In particular, in the group with a decrease in NSA of > 5°, the preoperative mean HKA was largely changed from 1.4° varus to 4.6° varus after THA. The prostheses with NSA of 132° and 135° also led to greater varus HKA changes than those with an NSA of 138°. Narrowing of the medial knee joint space was related to changes in the varus direction of the HKA, decrease in NSA, increase in femoral offset. Conclusion: A large reduction in NSA can lead to considerable varus limb alignment after THA, which can have adverse effects on the medial compartment of the ipsilateral knee.

아세틸 콜린 유발 검사시 허혈성 심전도 변화와 흉통의 발생이 내피세포 기능장애에 미치는 영향

최철웅(Cheol Ung Choi),나승운(Seung-Woon Rha),김선원(Sun Won Kim),나진오(Jin Oh Na),임홍의(Hong Euy Lim),김진원(Jin Won Kim),김응주(Eung Ju Kim),한성우(Seong Woo Han),박창규(Chang Gyu Park),서홍석(Hong Seog Seo),오동주(Dong Joo Oh) 대한임상노인의학회 2010 대한임상노인의학회지 Vol.11 No.4

연구배경: 아세틸 콜린 유발 검사시 발생하는 흉통과 허혈성 심전도 변화가 아세틸 콜린에 의해 발생하는 관상동맥의 내피세포 기능에 어떤 영향을 주는지 알아보고자 했다. 방법: 흉통으로 내원하여 관상동맥 조영술과 아세틸 콜린 유발검사를 시행받은 1,085명의 환자를 대상으로 하였다. 아세틸 콜린 유발 검사를 하는 동안 허혈성 심전도 변화 및 흉통의 발생 유무에 따른 관상동맥 내피세포 기능의 특징을 비교하였다. 결과: 539명의 환자에서 아세틸 콜린 검사시 내피세포 기능 장애가 발생 하였다. 허혈성 심전도 변화가 있었던 그룹이 심전도 변화가 없었던 그룹보다 흉통이 더 많았고(78.1% vs. 60.8%, P=0.007), 관상동맥 조영술상 다발성 관상동맥 경련이 빈번하였고(59.4% vs. 40.6%, P=0.004), 관상동맥의 경련 정도도 더 심하였다(64.1% vs. 46.5%, P=0.006). 흉통이 있었던 그룹이 흉통이 없었던 그룹보다 허혈성 심전도 변화의 빈도가 더 높았다(14.7% vs. 7.5%, P=0.007). 또한 흉통이 있었던 그룹이 관상동맥 경련이 다발성으로 발생하는 경우가 많았고 (50.7% vs. 29.5%, P<0.001), 미만성으로 발생하는 경우가 많았고(87.1% vs. 75%, P<0.001), 관상동맥의 경련의 정도도 더 심하였다(51.6% vs. 43.5%, P=0.041). 결론: 아세틸 콜린 유발검사시 발생하는 허혈성 심전도 변화와 흉통은 관상동맥 경련의 정도와 경련이 발생하는 관상동맥 개수와 연관이 있다. Background: ECG changes and chest pain during acetylcholine (Ach) provocation tests may constitute important clinical parameters for Ach-induced endothelial dysfunction. We investigated the association between ischemic ECG changes and chest pain during the Ach-provocation test and angiographic characteristics of Ach-induced endothelial dysfunction. Methods: A total of 1,085 patients with anginal symptoms underwent diagnostic coronary angiography (CAG) and Ach-provocation tests. We compared angiographic characteristics of Ach-induced endothelial dysfunction according to the presence of ECG change and chest pain. Results: A total of 539 patients experienced Ach-induced endothelial dysfunction. Patients who experienced ECG change group suffered more frequent chest pain (78.1% vs. 60.8%, P=0.007), angiographically more frequent multiple coronary artery spasm (59.4% vs. 40.6%, P=0.004), and more severe coronary artery spasm (64.1% vs. 46.5%, P=0.006) than patients without ECG change. However, there was no difference in the length of endothelial dysfunction between the groups. The incidence of ischemic ECG changes in patients with chest pain was higher than in patients without chest pain (14.7% vs. 7.5%, P=0.007). Patients who experienced chest pain more often experienced multiple (50.7% vs. 29.5%, P<0.001), diffuse (87.1% vs. 75%, P<0.001), and severe coronary artery spasm (51.6% vs. 43.5%, P=0.041) than patients without chest pain. Conclusion: Ischemic ECG changes and chest pain during the Ach-provocation test are associated with multi-vessel involvement and severe coronary artery spasm. Chest pain is associated with the length of endothelial dysfunction, but ischemic ECG change is not.

X-ray Irradiation Induced Reversible Resistance Change in Pt/TiO₂/Pt Cells

Chang, Seo Hyoung,Kim, Jungho,Phatak, Charudatta,D’Aquila, Kenneth,Kim, Seong Keun,Kim, Jiyoon,Song, Seul Ji,Hwang, Cheol Seong,Eastman, Jeffrey A.,Freeland, John W.,Hong, Seungbum American Chemical Society 2014 ACS NANO Vol.8 No.2

<P>The interaction between X-rays and matter is an intriguing topic for both fundamental science and possible applications. In particular, synchrotron-based brilliant X-ray beams have been used as a powerful diagnostic tool to unveil nanoscale phenomena in functional materials. However, it has not been widely investigated how functional materials respond to the brilliant X-rays. Here, we report the X-ray-induced reversible resistance change in 40-nm-thick TiO<SUB>2</SUB> films sandwiched by Pt top and bottom electrodes, and propose the physical mechanism behind the emergent phenomenon. Our findings indicate that there exists a photovoltaic-like effect, which modulates the resistance reversibly by a few orders of magnitude, depending on the intensity of impinging X-rays. We found that this effect, combined with the X-ray irradiation induced phase transition confirmed by transmission electron microscopy, triggers a nonvolatile reversible resistance change. Understanding X-ray-controlled reversible resistance changes can provide possibilities to control initial resistance states of functional materials, which could be useful for future information and energy storage devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2014/ancac3.2014.8.issue-2/nn405867p/production/images/medium/nn-2013-05867p_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn405867p'>ACS Electronic Supporting Info</A></P>

급성 심근허혈에 따른 심실활성시간(Ventricular Activation Time)의 변화

한성욱,김윤년,김기영,남창욱,김기식,김권배 대한순환기학회 2001 Korean Circulation Journal Vol.31 No.3

Correlation between skeletal and dental changes after mandibular setback surgery-first orthodontic treatment

Chang-Hoon Rhee,Youn-Kyung Choi,Yong-Il Kim,Seong-Sik Kim,Soo-Byung Park,Woo-Sung Son 대한치과교정학회 2015 대한치과교정학회지 Vol.45 No.2

Objective: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. Methods: A retrospective study of 34 patients (23 men, 11 women; mean age, 26.2 ± 6.6 years) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. Results: The significant T0 to T1 mandibular changes occurred ?9.24 ± 3.97 mm horizontally. From T1 to T2, the mandible tended to move forward 1.22 ± 2.02 mm, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = ?0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Poperpendicular plane (r = 0.758, p = 0.011). Conclusions: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.

Multi-temporal NDVI Change Patterns and Global Land Cover Dynamics

성정창,Seong, Jeong-Chang The Korean Association of Geographic Information S 2000 한국지리정보학회지 Vol.3 No.3

이 연구에서는 NOAA/NASA Pathfinder AVHRR Land Data Sets를 이용하여 시계열 NDVI 자료를 분석하였다. 1982년부터 1994년까지의 자료를 분석한 결과, 연평균 NDVI의 경우, 1982년, 1989년 및 1990년의 자료에서 심각한 계통적 편차가 나타났다. 이 연구에서는 엘니뇨와 위성 센서, 위성자료 처리 알고리듬 및 지표피복의 변화를 통하여 어느 정도의 계통적 편차를 설명할 수 있었다. 한편 식물 성장기의 자료를 이용한 연구기간 동안의 NDVI 변화 추세는 아시아 지역의 토지피복 변화와 많은 관련이 있는 것으로 나타났다. Average annual NDVI values from the NOAA/NASA Pathfinder AVHRR Land Data Sets from 1982 to 1994 showed comprehensive systematic displacement patterns in Asia. Inter-annual growing season data, however, did not show such systematic patterns. The most likely cause for the abrupt displacements, which appear especially in 1982, 1989 and 1990, may be changes in satellite sensors, although global warming, El Ni$\tilde{n}$o-Southern Oscillation events, changes in processing algorithms, and changes in land-use patterns in various parts of Asia may also play some role. The results suggest that researchers must be extremely careful in their inter-annual global change research, since direct use of the raw data could cause unexpected results. Growing-season NDVI shows decreases throughout most of Southeast Asia and modest gains in northern China and some parts in India, which could be related to land-use and land-cover changes.

RCP 8.5 기후변화 시나리오에 따른 소나무림과 굴참나무림의 산림 탄소 동태 변화 추정 연구

이종열 ( Jong Yeol Lee ),한승현 ( Seung Hyun Han ),김성준 ( Seong Jun Kim ),장한나 ( Han Na Chang ),이명종 ( Myong Jong Yi ),박관수 ( Gwan Soo Park ),김춘식 ( Choon Sig Kim ),손영모 ( Yeong Mo Son ),김래현 ( Rae Hyun Kim ),손요환 한국농림기상학회 2015 한국농림기상학회지 Vol.17 No.1

산림은 많은 양의 탄소를 저장하고 있으며, 산림 탄소 동태는 기후변화에 따라 변화할 것으로 예상된다. 본 연구는 우리나라 산림에서 가장 우점하는 침엽수종과 활엽수종인 소나무림과 참나무림을 대상으로 최근 개발 및 개선된 한국형산림토양탄소모델(Korean ForestSoil Carbon model; KFSC model)을 이용하여 두 가지 기후변화 시나리오(2012년 기온이 2100년까지 유지되는 시나리오(CT), Representative Concentration Pathway(RCP) 8.5 시나리오) 하에서의 산림 탄소 동태를 예측하였다. 5차 국가산림자원조사 자료로부터 소나무림과 굴참나무림 조사구들을 추출한 뒤, 이를 행정구역(9개 도, 7개 특별·광역시) 및 영급(1-5영급, 6영급이상)별로 분류하여 탄소 동태 모의 단위를 설정하였다. 탄소 저장고는 2012년을 기준으로 초기화하였으며, 모의 기간인 2012년부터 2100년까지 모든 교란은 고려하지 않았다. 모의 결과 산림 탄소 저장량은 시간이 경과함에 따라 전반적으로 증가하지만, CT 시나리오에 비하여 RCP 8.5 시나리오 하에서 산림 탄소 저장량이 낮게 나타났다. 소나무림의 탄소 저장량(Tg C)은 2012년에 260.4에서 2100년에는 각각 395.3(CT 시나리오) 및 384.1(RCP 8.5 시나리오)로 증가하였다. 굴 참나무림의 탄소 저장량(Tg C)은 2012년에 124.4에서 2100년에는 219.5(CT 시나리오) 및 204.7(RCP 8.5 시나리오)로 각각 증가하였다. 5차 국가산림자원조사 자료와 비교한 결과, 고사유기물 탄소 저장량의 초기값은 타당한 것으로 나타났다. 모의 기간 동안 소나무림과 굴참나무림의 연간 탄소 흡수율(g C m-2 yr-1)은 CT 시나리오 하에서 각각 71.1과 193.5, RCP8.5 시나리오 하에서 각각 65.8과 164.2로 추정된다. 따라서 우리나라 소나무림과 굴참나무림의 탄소 흡수잠재력은 지구 온난화에 의하여 감소할 것으로 예상된다. 비록 모델의 구조와 파라미터로부터 불확실성이 존재하지만 본 연구는 미래 산림 탄소 동태 파악에 기여할 것으로 기대된다. Forests contain a huge amount of carbon (C) and climate change could affect forest C dynamics. This study was conducted to predict the C dynamics of Pinus densiflora and Quercus variabilis forests, which are the most dominant needleleaf and broadleaf forests in Korea, using the Korean Forest Soil Carbon (KFSC) model under the two climate change scenarios (2012-2100; Constant Temperature (CT) scenario and Representative Concentration Pathway (RCP) 8.5 scenario). To construct simulation unit, the forest land areas for those two species in the 5th National Forest Inventory (NFI) data were sorted by administrative district and stand age class. The C pools were initialized at 2012, and any disturbance was not considered during the simulation period. Although the forest C stocks of two species generally increased over time, the forest C stocks under the RCP 8.5 scenario were less than those stocks under the CT scenario. The C stocks of P. densiflora forests increased from 260.4 Tg C in 2012 to 395.3 (CT scenario) or 384.1 Tg C (RCP 8.5 scenario) in 2100. For Q. variabilis forests, the C stocks increased from 124.4 Tg C in 2012 to 219.5 (CT scenario) or 204.7 (RCP 8.5 scenario) Tg C in 2100. Compared to 5th NFI data, the initial value of C stocks in dead organic matter C pools seemed valid. Accordingly, the annual C sequestration rates of the two species over the simulation period under the RCP 8.5 scenario (65.8 and 164.2 g C m-2 yr-1 for P. densiflora and Q. variabilis) were lower than those values under the CT scenario (71.1 and 193.5 g C m-2 yr-1 for P. densiflora and Q. variabilis). We concluded that the C sequestration potential of P. densiflora and Q. variabilis forests could be decreased by climate change. Although there were uncertainties from parameters and model structure, this study could contribute to elucidating the C dynamics of South Korean forests in future.

전력 수요 시계열 분석과 장기예측

장성연(Seong Yeon Chang) 한국자료분석학회 2023 Journal of the Korean Data Analysis Society Vol.25 No.4

본 연구는 전력 수요함수를 구성하는 경제변수들의 시계열 특성을 살펴보고 전력 수요 예측모형을 제안한다. 일반적으로 전력 수요는 단위근(unit root)을 갖는 시계열 자료로 알려져 있으며, 변수들 간의 공적분(cointegration) 관계를 고려한 수요 함수 추정 및 수요 예측 연구가 널리진행되었다. 본 연구에서는 2006년 1월부터 2022년 12월까지의 월간 시계열 자료를 사용하여 단위근 검정과 구조변화(structural change) 검정을 시행하였다. 이 시기에 한국 사회는 급격한 변화를 경험하였기 때문에 분석에 사용된 시계열 자료들이 구조변화를 겪었을 가능성이 매우 크다.기울기 변화를 경험한 추세 정상(trend-stationary) 시계열 자료에 대해 기울기 변화를 고려하지 않고 단위근 검정을 시행한다면 단위근 귀무가설이 기각되지 않는 경향이 있음이 잘 알려져 있다.본 연구에서는 단위근 검정을 시행할 때 구조변화의 가능성을 고려하였다. 검정 결과를 통해 전력 수요 함수를 구성하는 변수들이 구조변화를 갖는 추세 정상 시계열 자료임을 확인하였다. 이결과를 바탕으로 공적분 회귀모형 대신 구조변화를 고려한 회귀모형을 실증분석하였고, 2023년부터 2050년까지의 장기 전력 수요 예측을 시행하였다. This study considers the time series characteristics in residential electricity demand function and forecasts long-run electricity demand in Korea. It is widely known that electricity demand and its determinants are unit root processes, so that estimating and forecasting the electricity demand function based on cointegration relationship are common in empirical analyses. We apply unit root tests on monthly time series data for the period 2006:01-2022:12. Korea has experienced the rapid development and social changes over this period, which provides convincing evidence of the possibility of structural changes. The unit root test of Dickey, Fuller (1979) tends to be biased in favor of non-rejection of the unit root null hypothesis if the process considered is trend-stationary with a slope change. What we found is that electricity demand and its determinants are trend-stationary processes allowing for a slope change, whereby there is no need to invoke either cointegration regression model or error-correction model under the unit root assumption. We apply a regression model with a structural change to estimate the residential electricity demand function and forecast the long-run electricity demand for the period 2023-2050.

日中時間 變動에 따른 白鼠의 生理變化에 對한 補肝湯 瀉肝湯의 影響에 關한 硏究

金成圭,洪茂昌,金完熙 慶熙大學校韓醫科大學韓醫學硏究所 1986 慶熙韓醫大論文集 Vol.9 No.-

카드뮴 측적량과 붕어(Carassius auratus) 아가미 조직 변화의 상관성에 관한 연구

배희경,김은경,남성숙,문창규,전성환,나진균,박광식 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.1

Histopathological changes and cadmium accumulations in the gills were investigated in crucian carp (Carassius auratus) exposed to 0, 0.01, 0.1, 0.5 mg/l cadmium (Cd)concentrations for 25 days. After 25 days of exposure, cadmium accumulations increased in each of the different exposure concentrations. Histopathological changes in the gills of curcian carp exposed to cadmium included the acidification of mucous cell, the terminal clubbing of lamellae, the hyperplasia of epitherial cell and the curved of secondary lamellae. The similar histopathological changes were observed once the accumulations of cadmium reached the similar levels found in the present study with the different exposure schemes. Also the acidification of mucous cell in gills appeared when cadmium accumulations reached 5 ㎍/g and more. These results suggested that histopathological changes in the gills, an appearance of mucous cell acidification, be used to estimate the relation between toxic effect and cadmium accumulations in the gills.