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Seismic behavior characteristics of seismic-protective bridges according to seismic analysis methodologies
No full text지진보호장치 교량의 지진 해석기법에 따른 지진 거동 특성 울산대학교 대학원 건설환경공학과 강 태 훈 최근 전 세계적으로 대규모 지진이 발생하여 인적, 물적인 피해가 심각해지고 있다. 또한, 국내에서는 2016년부터 규모 3.0 이상의 지진 횟수가 급격히 증가하고 있다. 이러한 상황에 서 재해 시 인적, 물적 자원을 수송하는 교량과 같은 국가적 주요 구조물의 내진성능 확보 가 필요하다. 신설 교량 경우 지진·화산재해대책법에 의거하여 1992년부터 내진설계를 실시 하고 있지만 내진설계가 되어있지 않은 기존 교량은 내진성능평가를 수행하여 내진성능을 확인한 후 필요 시 내진보강설계와 내진보강공사를 하여 내진성능을 확보해야 한다. 기존 구조물(교량)에 대한 내진성능평가를 할 때에는 가장 보수적인 해석방법이라고 평가받는 일 반적인 응답이력해석을 사용하지만 신설 구조물(교량)을 내진 설계할 때에는 지반과 구조물 의 상호작용을 고려한 부지특성 응답이력해석을 사용하기도 한다. 본 연구에서는 많은 내진보강 방안 중 지진보호장치를 설치한 보강방안으로 전단키 및 댐 퍼를 설치한 교량에 대해 각각 일반 응답이력해석, 부지특성 응답이력해석, 부지특성 다지 점가진해석 3가지 기법에 따른 지진거동특성을 분석한다. 전단키는 상부구조의 온도변화에 따른 변위를 수용하기 위하여 적정한 갭(gap)을 두고 가동단 교각에 설치하여 고정단 교각 에 집중되는 지진력을 가동단 교각으로 분산하는 장치이며 지진해석 시에는 갭에 따른 비선 형 지진해석이 필요하다. 댐퍼도 마찬가지로 가동단 교각에 설치하여 고정단 교각에 집중되 는 가동단 교각으로 지진력을 분산하고, 또한 댐퍼의 감쇠에 의한 지진력 감소도 함께 도모 하는 장치이다. 댐퍼의 감쇠효과는 상부구조의 응답속도에 의존하므로 전단키와 마찬가지로 비선형 이력해석이 필요하다. 따라서, 본 연구에서는 지진보호장치(전단키, 댐퍼)가 설치된 교량을 현재 내진성능평가 시 사용하는 일반적인 응답이력해석을 포함하여, 부지특성 응답이력해석, 부지특성 다지점가진 응답이력해석까지 총 3가지 지진해석기법으로 해석 후 교량의 지진거동특성을 분석하였다.Maste
Performance of the EDACS-ADP incorporating highsensitivity troponin assay: Do components of major adverse cardiac events matter?
No full textBackground: The accelerated diagnostic protocol (ADP) using the Emergency Department Assessment of Chest pain Score (EDACS-ADP), a tool to identify patients at low risk of a major adverse cardiac event (MACE) among patients presenting with chest pain to the emergency department, was developed using a contemporary troponin assay. This study was performed to validate and compare the performance of the EDACS-ADP incorporating high-sensitivity cardiac troponin I between patients who had a 30-day MACE with and without unstable angina (MACE I and II, respectively).
Methods: A single-center prospective observational study of adult patients presenting with chest pain suggestive of acute coronary syndrome was performed. The performance of EDACS-ADP in predicting MACE was assessed by calculating the sensitivity and negative predictive value.
Results: Of the 1,304 patients prospectively enrolled, 399 (30.6%; 95% confidence interval [95% CI]: 27.7%-33.8%) were considered low-risk using the EDACS-ADP. Among them, the rates of MACE I and II were 1.3% (5/399) and 1.0% (4/399), respectively. The EDACS-ADP showed sensitivities and negative predictive values of 98.8% (95% CI: 97.2%-99.6%) and 98.7% (95% CI: 97.0%-99.5%) for MACE I and 98.7% (95% CI: 96.8%-99.7%) and 99.0% (95% CI: 97.4%-99.6%) for MACE II, respectively.
Conclusion: EDACS-ADP could help identify patients as safe for early discharge. However, when unstable angina was added to the outcome, the 30-day MACE rate among the designated low-risk patients remained above the level acceptable for early discharge without further evaluation
Changes in Nasal Tip Aesthetics Over Time Following Asian Tip Plasty
No full textObjectives: This study aimed to evaluate the sequential postoperative changes in tip aesthetics, by evaluating the aesthetic performance of the septal extension graft with or without tip grafting.
Methods: A total of 62 patients who underwent rhinoplasty with tip plasty were included. Using a three-dimensional scanner, we measured anthropometric aesthetic features of the nasal tip, including tip height, tip width, nasolabial angle, and columellar lobular angle. Preoperative and 1-month and 12-month postoperative anthropometric parameters were compared. The patients were grouped according to surgical techniques (i.e., septal extension only and septal extension plus tip grafting groups) and subtype of tip graft.
Results: The 1-month postoperative values of all four aesthetic features were significantly increased compared with the preoperative values. The tip height, tip width, and nasolabial angle at 12 months were significantly decreased compared with 1 month post-operation values, whereas the tip height and width were still greater than the preoperative values. No difference was found between 1 and 12 month values of columellar lobular angle. There were no differences in the degree of decrease in tip height, tip width, nasolabial angle, and columellar lobular angle between the septal extension graft only and septal extension graft plus tip graft groups. There were no differences in the tip graft by subtypes, single- and multi-layer tip grafts.
Conclusions: Increased tip height, tip width, and widened nasolabial angle gained immediately after septal extension grafting surgery gradually decreased over the year regardless of addition of tip graft or tip grafting methods
Development of window scheduler algorithm exploiting natural ventilation and thermal mass for building energy simulation and smart home controls
No full textBuilding energy simulations often rely on abstract assumptions when it comes to natural ventilation, such as ‘windows always open [or closed]’ or ‘windows open when outdoor temperature is below a certain threshold.’ However, simulations based on these assumptions fail to fully exploit the cooling potential of natural ventilation, as its effectiveness can be enhanced or diminished by various factors, including the presence of thermal mass. This issue also extends to smart home controls, where determining the window schedule becomes challenging without information about the building's response to outdoor conditions. To address these issues, this study has developed an analytical model for window operation schedules that leverages the passive cooling from natural ventilation. The analytical model was validated against a Modelica simulation. A case study utilizing the BESTEST model of ANSI/ASHRAE Standard 140 underwent validation with EnergyPlus simulations, showing strong concordance. The algorithm provides window schedule recommendations adapted to various airflow rates, thermal masses, and climate variations. The case study demonstrated that proper window scheduling could reduce indoor temperature by up to 8 °C under the given simulation settings, thereby improving resilience and indicating potential energy savings. Furthermore, the paper explores the potential opportunities and challenges this approach presents, especially for building simulation and smart home applications
Distal normal vessel diameter might be associated with silent brain infarcts after stenting for symptomatic carotid stenosis
No full textBackground: Carotid artery stenting (CAS) has been the standard treatment for carotid stenosis because it is less invasive; however, the risk of periprocedural thromboembolism is high. We investigated the predictors for silent brain infarcts (SBIs), focusing on embolic protection in CAS.
Methods: This study was single-center retrospective study, and we obtained baseline demographics and clinical, laboratory, and periprocedural variables of patients who underwent CAS. Also, methods used for embolic protection (no EPD, distal EPD, or proximal balloon guiding catheter) during CAS were obtained. Distal normal vessel diameter was defined as the diameter of cervical internal carotid artery where the artery wall becomes parallel. Diffusion-weighted imaging was performed before and after procedure to detect SBIs. The primary outcome was stented territory SBIs, and the secondary outcomes were any territories SBIs and stented territory SBIs in cases with EPD.
Results: A total of 196 CAS procedures with mean age 69.1 ± 9.9 years were included. After CAS, stented territory SBIs occurred in 53 (27.0 %) cases and any territories SBIs in 60 (30.6 %) cases. Univariable analyses revealed that distal normal vessel diameter (odds ratio = 1.71, 95 % confidence interval = 1.20-2.43, P = 0.003) was associated with the occurrence of stented territory SBIs after CAS. After adjusting for potential variables, larger distal normal vessel diameter (1.61 [1.10-2.36], P = 0.014) increased the occurrence of SBIs after CAS. Consistent results were obtained when the outcome was any territories SBIs or stented territory SBIs in cases with EPD.
Conclusions: Distal normal vessel diameter was a predictor for the occurrence of SBI after CAS. The passable pore size of EPDs may vary depending on vessel diameter, and may impact the occurrence of SBIs
Hedgehog signaling is involved in acquired resistance against KRASG12C inhibitors in lung cancer cells
No full textAlthough KRASG12C inhibitors have shown promising activity in lung adenocarcinomas harboring KRASG12C, acquired resistance to these therapies eventually occurs in most patients. Re-expression of KRAS is thought to be one of the main causes of acquired resistance. However, the mechanism through which cancer cells re-express KRAS is not fully understood. Here, the present study reports that the Hedgehog signal is induced by KRASG12C inhibitors and mediates KRAS re-expression in cancer cells treated with a KRASG12C inhibitor. Further, KRASG12C inhibitors induced the formation of primary cilia and activated the Hedgehog-GLI-1 pathway. GLI-1 binds to the KRAS promoter region, enhancing KRAS promoter activity and KRAS expression. Inhibition of GLI using siRNA or the smoothened (Smo) inhibitor suppressed re- expression of KRAS in cells treated with a KRASG12C inhibitor. In addition, the KRASG12C inhibitors decreased Aurora kinase A (AURKA) levels in cancer cells, and inhibition of AURKA using siRNA or inhibitors led to increased expression levels of GLI-1 and KRAS even in the absence of KRAS inhibitor. Ectopic expression of AURKA attenuated the effect of KRASG12C inhibitors on the expression of GLI-1 and re-expression of KRAS. Together, these findings demonstrate the important role of AURKA, primary cilia, and Hedgehog signals in the re-expression of KRAS and therefore the induction of acquired resistance to KRASG12C inhibitors, and provide a rationale for targeting Hedgehog signaling to overcome acquired resistance to KRASG12C inhibitors. Running title: Hh signaling induces acquired resistance against KRASG12C inhibitorsDocto
The Effect of workplace hazards and risk factors on psychological Well-Being - Focusing on the mediating effect of job satisfaction
No full text본 연구는 1인당 국민소득이 3만불을 넘어서 삶의 질이 중요시 되는 최근 시대상황을 반영하여, 작업장의 유해위험요인과 직무만족도 및 심리적 웰빙간의 관계를 알아보기 위해 한국산업안전보건연구원에서 2023년도에 실시한 「제7차 근로환경조사」자료를 대상으로 SPSS와 AMOS를 활용하여 요인분석, 타당도 분석 및 구조방정식 모형을 통해 잠재변수간 관계와 영향력을 검증하였다. 연구결과는 다음과 같다. 첫째, 작업장의 유해위험요인은 심리적 웰빙에 부(-)의 영향을 미치는 것으로 나타났다. 둘째, 작업장의 유해위험요인은 직무만족에 부(-)의 영향을 미치는 것으로 나타났다. 셋째, 직무만족은 심리적 웰빙에 정(+)의 영향을 미치는 것으로 나타났다. 넷째, 직무만족은 작업장의 유해위험요인과 심리적 웰빙 수준과의 관계에서 부분매개역할을 하는 것으로 나타났다. 정리하면, 작업장의 유해위험요인은 직무만족과 심리적 웰빙수준을 낮추고 직무만족은 작업장의 유해위험요인과 심리적 웰빙 수준과의 관계에서 매개역할을 한다. 본 연구의 결과, 경영진의 리더십이 작업장 유해위험 요인을 관리하여 안전한 일터를 만드는 것을 경영의 최우선으로 삼게 되기를 기대한다. 사고를 방지하여 인명 및 재산상 손실을 줄일 수 있을 뿐만 아니라 직무에 매진함으로써 높은 성과를 거두어 궁극적으로 이윤을 창출하는 선순환 구조로 기업을 변화시킬 수 있기 때문이다. 사고 후 처벌을 면하기 위해 로펌에 많은 댓가를 지불하는 소 잃고 외양간 고치는 사후 수습 행태에서 벗어나야 한다. 자율안전시스템 구축을 통해 사망사고를 획기적으로 줄임으로써, 우리나라도 사망사고 없는 OECD 선진그룹에 합류할 수 있기를 기대한다.
This study used SPSS and AMOS to verify the relationship between workplace hazards and risk factors, job satisfaction, and psychological well-being using the data from the 7th Work Environment Survey conducted by the Korea Occupational Safety and Health Research Institute in 2023. The study verified the relationship and influence between latent variables through factor analysis, validity analysis, and structural equation modeling. The results of the study are as follows. First, workplace hazards and risk factors were found to have a negative effect on psychological well-being. Second, workplace hazards and risk factors were found to have a negative effect on job satisfaction. Third, job satisfaction was found to have a positive effect on psychological well-being. Fourth, job satisfaction was found to have a partial mediating role in the relationship between workplace hazards and risk factors and psychological well-being levels. In summary, workplace hazards and risk factors lower job satisfaction and psychological well-being levels, and job satisfaction plays a mediating role in the relationship between workplace hazards and risk factors and psychological well-being levels. As a result of this study, it is expected that management leadership will make managing workplace hazards and risk factors a top management priority to create a safe workplace. This is because it can not only prevent accidents and reduce loss of life and property, but also transform the company into a virtuous cycle structure where employees can achieve high performance by focusing on their jobs and ultimately create profits. Through this, I hope that our country can also join the OECD advanced group with no fatal accidents
Effect of Fashion Mobile App Usage Status and Smartphone Knowledge on Consumer’s Perceived Risk and Word-of-Mouth
No full textBackground/Objectives: This study examined the effects of the fashion mobile app usage status and smartphone knowledge on consumers’ perceived risks and wordof-mouth. Methods: The participants in this study were 234 women and men aged 20s and older. The survey was conducted using a questionnaire. Data were analyzed by frequency, factor, reliability, cluster, t-test, and regression analyses using SPSS 27.0. Results: First, the consumer’s perceived risk was extracted from two factors: product and security risk factors. Second, in groups with experience downloading fashion mobile apps, security risk factors affected word-of-mouth and repurchase intentions negatively, while word-of-mouth affected repurchase intentions positively. Third, in the group with high shopping frequency, product risk factors, security risk factors, and word-of-mouth influenced repurchase intention. In the group with high shopping frequency, product risk, security risk, and word-of-mouth were factors that influenced repurchase intention. Fourth, even in groups with high search times, security risk factors had a negative effect on word-of-mouth and repurchase intention, while word-of-mouth had a positive effect on repurchase intention. Fifth, in groups with low smartphone knowledge, the perceived risk did not affect word-of-mouth or repurchase intention. This study confirmed that the fashion use of mobile apps and smartphone knowledge affects perceived risks and word-of-mouth and is a significant variable of mobile usage status, which is used as an additional variable, useful for examining consumer characteristics. The results provide important data for mobile fashion marketing strategies. Conclusion/Implications: This study confirmed that the fashion use of mobile apps and smartphone knowledge affects perceived risks and word-of-mouth, and it is a significant variable in mobile usage status, which was used as an additional variable, useful for examining consumer characteristics. The results are important for fashion mobile marketing strategies
Long-Term Outcomes of Colon Conduits in Surgery for Primary Esophageal Cancer: A Propensity Score-Matched Comparison to Gastric Conduits
No full textBackground: In the treatment of esophageal cancer, a gastric conduit is typically the first choice. However, when the stomach is not a viable option, the usual alternative is a colon conduit. This study compared the long-term surgical outcomes of gastric and colon conduits over the same interval and aimed to identify factors influencing the prognosis.
Methods: A retrospective review was conducted of patients who underwent esophagectomy followed by reconstruction for primary esophageal cancer between January 2006 and December 2020.
Results: The study included 1,545 patients, with a gastric conduit used for 1,429 (92.5%) and a colon conduit for 116 (7.5%). Using propensity-matched analysis, 116 patients were selected from each group for comparison. No significant difference was observed in long-term survival between the gastric and colon conduit groups, irrespective of anastomosis level and pathological stage. A higher proportion of patients in the colon conduit group experienced postoperative complications compared to the gastric conduit group (57.8% vs. 25%, p<0.001). Multivariable analysis revealed that age over 65 years, body mass index below 22.0 kg/m2, neoadjuvant therapy, postoperative anastomotic leakage, and renal failure were risk factors for overall survival in patients with a colon conduit. Regarding conduit-related complications, cervical anastomosis was the only significant risk factor among those with a colon conduit.
Conclusion: Despite the association of colon conduits with high morbidity rates relative to gastric conduits, the long-term outcomes of colon conduits were acceptable. More consideration should be given perioperatively to the use of a colon conduit, particularly in cases involving cervical anastomosis
Patient Safety Personnel's Task analysis using Importance and Performance Analysis
No full textPurpose: This study aimed to identify tasks performed by patient safety personnel using importance-performance analysis.
Methods: An online survey was conducted during a mandatory educational course. The questionnaire consisted of 43 items categorized into four subscales: management of patient safety accidents, education of healthcare personnel, education of patients and guardians, and patient safety activities. Importance-performance analysis was employed to ascertain the relationship between the importance and performance of tasks conducted by patient safety personnel.
Results: A total of 145 patient safety personnel participated in the survey. The perceived importance of tasks by participants averaged 3.67 out of four, while the average performance was 3.40 out of four, indicating a significant difference (t=8.04, p<.001). Activities such as collecting patient safety reports, conducting root-cause analyses, and educating new employees were identified as low-performance tasks compared to their perceived importance.
Conclusion: Tasks recognized as having low importance but high performance among patient safety personnel should be addressed through increased awareness and education. Analyzing the causes of tasks with low importance and performance is crucial for recognizing their importance and implementing improvement measures