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One-Year Longitudinal Changes in Tau Accumulation on [18F]PI-2620 PET in the Alzheimer Spectrum
No full textWe investigated the longitudinal changes in cortical tau accumulation and their association with cognitive decline in patients in the Alzheimer disease (AD) continuum using 2-(2-([18F]fluoro)pyridin-4-yl)-9H-pyrrolo[2,3-b:4,5c']dipyridine ([18F]PI-2620) PET. Methods: We prospectively enrolled 52 participants (age, 69.7 ± 8.4 y; 18 men and 34 women): 7 with normal cognition, 28 with mild cognitive impairment, and 17 with AD. They all completed the [18F]PI-2620 and [18F]florbetaben PET, MRI, and neuropsychologic tests at baseline and, excepting the [18F]florbetaben PET, at the 1-y follow-up. Amyloid-β (Aβ) PET images were visually scored as positive (+) or negative (-). Patients on the AD continuum, including Aβ+ mild cognitive impairment and AD, were classified into early-onset (EO+) (<65 y old) or late-onset (LO+) (≥65 y old) groups. [18F]PI-2620 PET SUV ratios (SUVRs) were determined by calculating the cerebral-to-inferior cerebellar ratio. Cortical volumes were calculated using 3-dimensional T1-weighted MRI. The correlation between tau accumulation progression and cognitive decline was also investigated. Results: The global [18F]PI-2620 PET SUVRs were 1.04 ± 0.07 in 15 Aβ- patients, 1.18 ± 0.21 in 20 LO+ patients (age, 76.7 ± 3.8 y), and 1.54 ± 0.38 in 17 EO+ patients (age, 63.4 ± 5.4 y; P < 0.001) at baseline. The global SUVR increased over 1 y by 0.05 ± 0.07 (3.90%) and 0.13 ± 0.22 (8.41%) in the LO+ and EO+ groups, respectively, whereas in the Aβ- groups, it remained unchanged. The EO+ group showed higher global and regional tau deposition than did the Aβ- and LO+ groups (P < 0.05 for each) and rapid accumulation in Braak stage V (0.15 ± 0.25; 9.10% ± 12.27%; P = 0.016 and 0.008), Braak stage VI (0.08 ± 0.12; 7.16% ± 10.06%; P < 0.006 and 0.005), and global SUVR (P = 0.013) compared with the Aβ- group. In the EO+ group, the changes in SUVR in Braak stages II-VI were strongly correlated with the baseline and changes in verbal memory (P < 0.03). The LO+ group showed higher tau accumulation in Braak stage I-IV areas than did the Aβ- group (P < 0.001 for each). In the LO+ group, the change in SUVR in Braak stages III and IV moderately correlated with the change in attention (P < 0.05), and the change in SUVR in Braak stages V and VI moderately correlated with the change in visuospatial function (P < 0.005). Conclusion: These findings suggest that [18F]PI-2620 PET can be a biomarker to provide regional and chronologic information about tau pathology in the AD continuum
A study of Structural, Electrical, Low-E and Heating Properties of ZnO/Cu/ZnO films by Electron Beam irradiation
No full text본 연구에서는 RF/DC magnetron sputter를 이용하여 유리기판에 2 inch의 ZnO 타겟과 Cu 타겟을 각각 전력밀도 2.0 W/cm2와 4.0 W/cm2의 파워를 인가하여 ZnO(60 nm) 단층박막과 ZnO/Cu/ZnO 다층박막을 증착하였다. 다층박막의 효율적인 Cu 중간층 두께를 고찰하기 위해 상부와 하부 ZnO층의 두께 를 30 nm로 고정한 후, Cu의 두께를 증착 시간을 조절하여 7, 11, 15 nm를 가지는 다층박막을 제작하였고 XPS 활용한 깊이 방향으로 성분 분석을 통해 증착 시간에 따 른 Cu 중간층이 상하부 ZnO 박막 사이에 적절하게 삽입된 것을 확인하였다. ZCZ 다층박막의 전기광학적 특성을 비교한 결과 Cu 두께 11 nm에서 면저항 70.28 Ω/□, 가시광 평균 투과도(380-780 nm) 77.88%, 전기광학적 완성도(Figure of Merit)가 1.17×10-3 Ω-1로 가장 우수하였다. 최적의 조건인 ZCZ(30/11/30 nm)을 증착 후 결정성 변화는 XRD로 분석하였으며 약 46°에서 ZnO(102), 약 67°의 ZnO(201) 회절 피크가 측정되었고 다층박막의 결정 성은 적정 전자빔 조사에너지까지 향상됨을 확인할 수 있었다. 전자빔 조사에너지에 따른 특성변화 비교를 통해 표면거칠기(Root mean square, RMS)는 초기 1.54 nm에서 1.26 nm로 감소하였고 면저항 43.1 Ω/□, 가시광 평균 투과율 79.67 %로 전기광학적 완성도는 2.39 × 10-3 Ω-1로 가장 높은 것을 확인하였 다. 이는 적절한 전자빔 조사에너지로 인해 결정성 증가 및 거칠기 감소로 특성이 향 상되었다고 사료된다. 500 eV의 전자빔 조건에서 적외선 영역의 투과도를 분석한 결과 Low-Emissivity 특성이 나타나는 것을 확인하였고 발열테스트 및 반복재현성 테스트를 통하여 18V에 서 약 90.5℃ 까지 온도가 상승하고 반복적으로 온도 조절을 할 수 있는 것을 확인하 여 적절한 전자빔을 조사한 ZnO/Cu/ZnO(30/11/30nm) 다층박막이 Low-E 분야 및 투명면상발열체로 활용 가능한 투명전극소재로 가능성을 확인하였다.Maste
A Study on Obstacle Avoidance Algorithm of Multi-Copter Drone using an RGB-D Camera
No full text드론의 장애물 회피 알고리즘 기초 연구로써, PX4 오픈소스와 Depth Camera 를 이용하여 3DVFH* 장애물 회피 및 경로 생성 알고리즘을 분석 및 검증하였 다. Gazebo 시뮬레이션 환경을 구성하여 장애물 회피 알고리즘을 분석하였고, 실외 비행시험을 통해 장애물 회피 알고리즘을 검증하였다. Gazebo 시뮬레이션 에서 복잡하게 장애물이 있는 환경과 긴 벽이 있는 환경 등 다양한 비행 환경을 구성하여 회피 경로와 연관된 파라미터 조합을 통한 회피 성능 변화를 분석하였 고, 실외 비행에서 시뮬레이션 환경과 유사한 환경을 조성하여 비행 테스트를 수 행하였다. 대부분의 장애물에서 안정적인 회피 및 경로 생성이 되었지만, 빛 반사 가 되는 재질이거나 얇은 나뭇가지에서는 실험에 사용된 RGB-D 카메라의 한계 로 인해 장애물이 탐지되지 않았고, 회피하지 못하였다. 장애물 회피 알고리즘 성 능 개선을 위해 시뮬레이션에서 RGB-D 카메라 3개를 이용한 실험을 진행하였 고, 카메라 1개에 비해 빠른 회피 및 경로 생성 능력을 보여주었다.Maste
An Understanding of Keyword Networks on Research Trends on Jeju Tourism and Sports Tourism
No full textPurpose - The purpose of this study was to conduct a preliminary study to identify key trends on research articles indexed in KCI in relation to tourism in Jeju and sports tourism.
Design/methodology/approach - Information regarding research articles focused on Jeju tourism and sports tourism indexed in KCI (145 and 120 articles respectively) were collected and finally abstract written in Korean of 100 and 91 articles on sports tourism and Jeju tourism respectively were chosen for the further analysis after removing redundant articles. R program was used to analyze keyword frequencies, co-occurring terms, and degree/betweeness centrality measures and visualize the keyword network results.
Findings - Event, marketing, content, program, implication, service, stadium, and tourism destination have been identified as keywords with highest frequencies among research on sport tourism, whereas tourism destination, image, brand, content, data, Chinese, satisfaction, eco-tourism service, place of arrival were highly appearing terms among research on Jeju tourism.
Research implications or Originality - This study highlighted that Jeju has been interlinked with a range of terms such as programs influencing Jeju tourism, natural environment, tourism-related resources (e.g., museums, dramas, etc.), whereas sports has been closely related to sports event and vaiours types of sports (e.g., bicycle, staking, and scuber), but not to Jeju-do
Isolated Subtalar Repositional Arthrodesis Compared With Triple Arthrodesis for the Treatment of Progressive Collapsing Foot Deformity
No full textThe optimal extent of arthrodesis for severe and rigid progressive collapsing foot deformity is controversial. Traditionally, triple arthrodesis has been recommended; however, good results have been reported using subtalar arthrodesis only. We compared the results of triple arthrodesis and isolated subtalar repositional arthrodesis. A total of 22 symptomatic feet were evaluated retrospectively. Isolated subtalar repositional arthrodesis was performed in 13 cases (the subtalar group) and double or triple arthrodesis in 9 cases (the triple group). Various radiographic variables for assessing flatfoot and osteoarthritic changes in ankle and tarsal joints were measured and compared between the 2 groups at 3 time points: preoperatively, 3 months postoperatively, and 4 y postoperatively. Additionally, we analyzed various factors that affect postoperative valgus talar tilt in the ankle joint, which has been associated with poor prognosis. There were no differences in preoperative demographic data and the severity of the disease between the 2 groups; both groups showed improvement in radiographic parameters postoperatively compared with preoperative results. With the numbers available, no significant differences could be detected in postoperative radiographic measurements between the 2 groups. Of all the variables analyzed, postoperative hindfoot alignment angle was associated with postoperative talar tilt development. Additionally, postoperative talar tilt was observed more in triple group than in subtalar group. In conclusion, isolated subtalar repositional arthrodesis is an effective procedure to correct advanced progressive collapsing foot deformity. In addition, Chorpart joint arthrodesis with improper position can cause valgus talar tilt in the ankle joint
A Study on the Effects of Human Resources Expertise on Technical Guidance Activities and Performance to Prevent Construction Industrial Accidents
No full text건설재해예방전문지도기관 인력의 전문성이 기술지도 활동과 재해예방성과에 미치는 영향에 관한 연구 울산대학교 일반대학원 안전보건전문학과 이 상 근 공사금액 50억 원 미만의 소규모 건설공사 현장에서 발생하는 사고사망자 수는 건설공사 전체 사고사망자 수의 약 70%를 점유하고 있으며, 사고사망만인율은 전담 안전관리자가 배치되는 120억 원 이상의 건설현장보다 약 4배 이상 높은 실정이다. 따라서, 전담 안전관리자가 배치되지 않는 중소규모 건설현장에서 의무적으로 실시하는 기술지도 제도는 건설업 산업재해 예방을 위한 중요한 도구이다. 고용노동부에서는 건설재해예방전문지도기관(이하 ‘지도기관’이라 한다.)에 대한 평가 제도를 도입하였고, 안전보건공단에서 매년 지도기관의 운영체계(400점)와 업무성과(600점)에 대하여 평가하고 그 결과를 공개하고 있다. 이에 본 연구에서는 관련분야 전문가 면담 및 관계자 설문조사 등을 통해 공통적 으로 강조되고 있는 중소규모 건설현장 재해예방을 위해서는 지도요원의 전문성 향상 이 필요하다는 선행연구의 개선방안이 실제 지도기관 지도요원 자격과 역량강화 활동, 기술지도 보고서 내용 및 위탁계약 건설현장 재해율을 평가하고, 그 결과를 정량적인 점수로 부여한 기관평가 결과의 분석을 통해 확인할 수 있는지 검증하고자 한다. 본 연구를 위해 2021년 10월부터 2022년 9월까지 지도기관 171개소의 기술지도 실적을 대상으로 안전보건공단에서 전문가 2명이 지도기관에 직접 방문하여 실시한 평가결과 자료를 활용하였다. 자료는 IBM SPSS (V21)를 활용하여 기초통계분석, 타당 성 및 신뢰도 검증, 상관관계 및 회귀분석을 실시하였다. 본 연구의 결과를 살펴보면 다음과 같다. 첫째, 지도기관의 규모와 고급인력 보유 수준에 따라 기술지도활동 수준의 평균 값의 차이를 검증한 결과, 통계적으로 유의한 수준에서 지도기관의 규모가 클수록 (F=5.705, p<0.01), 고급인력의 수가 많을수록(F=5.252, p<0.01) 기술지도활동 수준이 높다는 것을 확인하였다. 둘째, 지도요원의 전문성 수준이 통계적으로 유의한 수준에서 기술지도활동(β =0.192, p<0.05)과 재해율 감소성과(β=0.186, p<0.05)에 정(+)의 영향을 미친다는 것 을 확인하였다. 셋째, 지도요원 전문성 수준과 재해율 감소성과 간의 관계에서 기술지도활동 수준의 매개역할은 Baron and Kenny(1986) 3단계 매개회귀분석을 통하여 부분매개 효과가 있다는 것을 확인하였다. 결론적으로 본 연구결과는 지도기관 지도요원의 전문성 수준이 기술지도활동 수준, 재해율 감소성과에 영향을 미치는 점을 확인할 수 있었고, 매개효과 검증 결 과 지도요원의 전문성 수준과 재해율 감소성과 간의 관계에서 기술지도활동 수준이 부분매개효과가 있는 것으로 확인하였다.
주제어 : 건설재해예방전문지도기관, 전문성, 기술지도활동, 산업재해예방성과, 기관 평가, 평가지표Maste
Effect of Opioids on Postoperative Pneumonia and Atelectasis in Lung Cancer Patients undergoing Lung Resection
No full textThis study aimed to investigate the effect of opioid analgesic use on the occurrence of postoperative pulmonary complications such as pneumonia and atelectasis in patients undergoing lung resection after a diagnosis of primary lung cancer.
This retrospective cohort study included 309 patients diagnosed with primary lung cancer who underwent lung resection from January 1, 2019, to December 31, 2023, in 1 general hospital in S city. General characteristics, perioperative factors, opioid analgesic use and postoperative pulmonary complications of the participants were collected using electronic medical records. For variables showing significant differences, multivariate logistic regression analysis was performed. Data were analysed using SPSS Statistics for Windows, version 27.0 (IBM Corp., Armonk, NY, USA) program.
The Incidence of postoperative pulmonary complications was 13.9%(43 patients). Multivariate analysis revealed that the risk factors for postoperative pulmonary complications included current smoking status (OR [Odds ratio]=5.466, 95% CI [Confidence interval]=2.006-14.898), past smoking history (OR=2.929, 95% CI=1.113-7.707), autoimmune diseases (OR=5.303, 95% CI=1.363-20.637), cardiac diseases (OR=4.896, 95% CI=1.486-16.128), albumin level less than 3.5g/dL (OR=4.820, 95% CI=1.568-14.815), operation duration more than 150 minutes (OR=2.580, 95% CI=1.022-6.514), intravenous morphine administration (OR=4.362, 95% CI=1.366 -13.925), and oral gabapentinoid (OR=4.468, 95% CI=1.520-13.139).
Factors influencing the occurrence of postoperative respiratory complications in these patients included smoking status, autoimmune diseases, cardiac diseases, albumin level, operation duration , intravenous morphine administration, and oral gabapentinoid use. The incidence could be reduced by prevention of available risk factors and by appropriate perioperative pulmonary interventions for those in high risk of respiratory complications.
Keywords: Lung Neoplasms, Postoperative Complications, Pulmonary Atelectasis, Pneumonectomy, Analgesics, Opioid|본 연구는 원발성 폐암을 진단받고 폐 절제술을 시행한 환자에서 마약성 진통제 사용이 수술후 합병증 중 폐렴과 무기폐 발생에 미치는 영향을 확인하기 위해 시행되었다.
일개 상급종합병원에서 2019년 1 월 1 일부터 2023 년 12 월 31일까지 원발성 폐암을 진단받고 폐 절제술을 시행한 309 명을 대상으로 한 후향적 코호트 연구이다. 수술후 호흡기계 합병증 발생 여부에 따른 일반적 특성, 수술전∙중∙후 특성, 마약성 진통제 사용을 비교하기 위해 다변량 로지스틱 회귀분석을 실시하였다. 자료는 전자의무기록을 통해 수집하였고, SPSS 를 이용하여 분석하였다.
수술후 호흡기계 합병증은 43명(13.9%)에서 발생하였다. 수술후 호흡기계 합병증 발생 영향 요인은 현재 흡연(OR [Odds ratio]=5.466, 95% CI [Confidence interval]=2.006-14.898), 과거 흡연(OR=2.929, 95% CI=1.113-7.707), 자가면역 질환(OR=5.303, 95% CI=1.363-20.637), 심장질환(OR=4.896, 95% CI=1.486- 16.128), 3.5g/dL 미만의 알부민(OR=4.820, 95% CI=1.568-14.815), 150 분을 초과하는 수술시간(OR=2.580, 95% CI=1.022-6.514), 정맥 모르핀 투여(OR=4.362, 95% CI=1.366-13.925), 경구 가바펜티노이드 투여(OR=4.468, 95% CI=1.520- 13.139)로 나타났다.
폐 절제술을 시행한 폐암 환자에서 호흡기계 합병증 발생 위험 요인은 흡연, 자가면역질환, 심장질환, 3.5g/dL 미만의 알부민, 150 분을 초과한 수술시간, 정맥 모르핀 투여, 경구 가바펜티노이드 투여로 확인되었다. 폐 절제술을 시행하는 환자에서 가능한 위험 요인을 예방하고, 호흡기계 합병증 발생 위험이 높을 것으로 예상되는 대상자에게 수술전과 수술후 적절한 폐 중재를 제공해 발생률을 낮출 수 있을 것으로 생각된다.
주요어 : 폐암, 수술후 합병증, 수술후 무기폐, 폐 절제술, 마약성 진통제Maste
Current practices of cervical epidural block for cervical radicular pain: a multicenter survey conducted by the Korean Pain Society
No full textBackground: Cervical epidural block (CEB) is an effective intervention for managing cervical radicular pain. This study aimed to investigate the current status of performing CEB in South Korea.
Methods: Pain physicians affiliated with the Korean Pain Society were asked to complete anonymous questionnaires regarding CEB between September and October 2022. The questionnaire consisted of 24 questions assessing the current status and methods of CEB in detail.
Results: Of the 198 surveys collected, 171 physicians (86.4%) reported performing CEB. Among those, the majority (94.7%) used fluoroscopy during the procedure. The paramedian interlaminar (IL) approach was the most preferred method (50.3%). Respondents performing fluoroscopic-guided IL CEB were categorized into two groups based on clinical experience: those with ≤10 years of experience (≤10-year group, n = 91) and those with >10 years of experience (>10-year group, n = 71). The proportion of physicians obtaining informed consent in the ≤10-year group and >10-year group was 50.5% and 56.3%, respectively. When entering the epidural space during IL CEB, the contralateral oblique view was the second most frequently used in both groups (≤10-year group, 42.9%; >10-year group, 29.6%). In targeting the upper cervical lesions (C3-4), the proportion of respondents who used an IL space higher than C6-7 was 17.6% in the ≤10-year group and 29.5% in the >10-year experience group.
Conclusions: This study demonstrated variability in the CEB technique used by pain physicians in South Korea. The findings highlight the need for education on informed consent and techniques to enhance safety
Analysis of Exercise Intensity Based on Cardiorespiratory Response in a Virtual Reality-Based Exercise Program for Firefighter Physical Fitness Enhancement
No full textOBJECTIVES
Current regulations for Korean firefighters primarily emphasize exercise during working hours without specifying particular exercise methods. This study aims to evaluate the exercise intensity of the stepwise Korean Firefighter Fitness Program (KFFP) using Kinect-based mixed reality device (Virtual mate, VM), considering the demanding 24-hour shift work and high physical strength requirements. The objective is to assess its potential as one of the exercise methods and provide valuable insights.
METHODS
CResearchers recruited 30 participants to evaluate the exercise intensity based on the cardiopulmonary responses induced by the Stepwise Korean Firefighter Fitness Program (KFFP) using Virtual Mate (VM). Initially, the participants' resting heart rate, maximum heart rate (HRmax), and maximum oxygen consumption (VO2max) were measured. Subsequently, researchers monitored the participants' cardiopulmonary responses by employing portable gas analyzers and wireless heart rate monitors while implementing the Stepwise KFFP with VM. Exercise intensity related to cardiopulmonary responses was recorded using both absolute parameters (VO2, HR) and relative parameters (%VO2max, %HRR, %HR). Researchers utilized repeated measures analysis of variance for statistical analysis.
RESULTS
The analysis of the stepwise KFFP using VM showed significant increases all parameters as the program advanced(p<.001). VO2 increased from around 19.4 ml/kg/min in Step 1 to approximately 22.8 ml/kg/min in Step 3. Similarly, %HRR rose from roughly 40.6% in Step 1 to about 53.9% in Step 3.
CONCLUSIONS
Upon evaluating the stepwise KFFP based on the exercise intensity levels recommended by ACSM, it is confirmed that the stepwise KFFP using VM comprises both moderate-intensity and highintensity exercises. This approach is deemed effective and can serve as a fitness management method for firefighters working in 24-hour shift patterns that demand high fitness levels
Direct oral anticoagulants for oral anticoagulants-naïve Asian patients with atrial fibrillation and end-stage renal disease undergoing dialysis
No full textIn Asian patients with atrial fibrillation (AF) and end-stage renal disease (ESRD) undergoing dialysis, the use of direct oral anticoagulants (DOACs) remains debatable. From the national health insurance claims data in South Korea, we included 425 new users of OAC among patients with non-valvular AF and ESRD undergoing dialysis between 2013 and 2020. Patients were categorized into DOAC (n = 106) and warfarin group (n = 319). Clinical outcomes, including ischemic stroke, myocardial infarction (MI), intracranial hemorrhage (ICH), and gastrointestinal (GI) bleeding, were compared between the two groups using inverse probability of treatment weighting (IPTW) analysis. During the median follow-up of 3.2 years, the incidence of ischemic stroke was significantly reduced in the DOAC compared to the warfarin group [Hazard ratio (HR) 0.07; P = 0.001]. However, the incidence of MI (HR 1.32; P = 0.41) and GI bleeding (HR 1.78; P = 0.06) were not significantly different between the two groups. No ICH events occurred in the DOAC group, although the incidence rate did not differ significantly between the two groups (P = 0.17). In Asian patients with AF and ESRD undergoing dialysis, DOACs may be associated with a reduced risk of ischemic stroke compared with warfarin. The MI, ICH, and GI bleeding rates may be comparable between DOACs and warfarin