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Good daylighting design in buildings not only provides a comfortable, luminous environment, but it also helps save energy and create a comfortable and healthy environment for the occupants of the building. The importance of receiving daylight in educational buildings is due to the time synchronization of operating hours of the school, and daylight plenitude in the sky. Daylight improves environmental quality and saves energy by minimizing artificial lighting requirements and, thus, reducing the cooling load. Furthermore, window design is a primary sustainable approach to achieving environmental goals and contributes to comfort and satisfaction. The present study analyzes the variations of annual thermal energy demand and useful daylight illuminance to determine the optimal Window-to-Wall Ratio (WWR) of a simulated primary school classroom in Tehran in two directions of the south and the north. Twelve different window sizes in two types of horizontally expanded windows (the height of the window remains constant, the width is varied) and vertically expanded windows (the width of the window remains constant, the height is varied) were compared from the two perspectives of Useful Daylight Illuminance (UDI) and thermal and electrical energy using the Honeybee plugin of Grasshopper. The results of this research demonstrate that vertically expanded windows are more energy-efficient in classrooms while they give almost the same UDI as horizontally expanded windows in both south and north facades. Overall, WWR in the range of 25% to 35% in the south facade displayed the best performance in daylight and thermal loads. [ABSTRACT FROM AUTHOR]

Objective: Advanced age is a risk factor in cardiac surgery contributing significantly to a worse outcome. The reasons are frailty and multimorbidity. In this study, we asked: Is there an aging of the heart which differs from chronological age?, Methods: Propensity score matching was performed between 115 seniors ≥ 80 years and 345 juniors < 80 years. After the patients were found to be comparable in terms of cardiac and noncardiac disease and risk profiles, they were further analyzed for cardiac parameters. In addition, the seniors and juniors were compared in terms of cardiac health and postoperative outcome. Furthermore, the patients were subdivided into several age groups (<60 years, 60-69 years, 70-79 years, and >80 years) and compared regarding outcome., Results: The seniors demonstrated significantly lower tricuspid annular plane systolic excursion (TAPSE), significantly more frequent diastolic dysfunction, significantly higher plasma levels of NT-proBNP, and significantly larger left ventricular end-diastolic and end-systolic diameters and left atrial diameters ( p < 0.001, respectively). Furthermore, in-hospital mortality and most postoperative complications were significantly higher in seniors compared with juniors. While old cardiac healthy patients showed better outcome than old cardiac aged patients, the outcome from young cardiac aged patients was better than old cardiac aged patients. The outcome and survival deteriorated with increasing life decades., Conclusions: The elderly suffer significantly more from cardiac deterioration, i.e., cardiac aging, and show higher multimorbidity. Mortality risk is significantly higher and they suffer more often from a complicated postoperative course compared to younger patients. Further approaches to prevention and treatment of cardiac aging are needed to address the needs of an aging society.

Objective : Cardiosurgical mitral valve repair (MVR) cannot be easily replaced by other interventional procedures due to the complexity of mitral valve regurgitation as well as physiologic and anatomic repair techniques. A wide variety of techniques have been adopted for proper reconstruction of posterior leaflet prolapse. We investigated the long-term results of quadrangular resections and compared them with a simplified reconstruction maneuver, the inverse plication. Methods : We retrospectively collected data from 1977 patients after mitral valve repair between 2004 and 2022. After considering inclusion and exclusion criteria, we analyzed data from 180 patients after MVR with and without concomitant procedures such as CABG and/or aortic valve replacement (AVR). All MVRs were performed with a semi-rigid annuloplasty ring. A total of 180 patients received quadrangular resection (QuadRes, N = 120)) or inverse plication (InvPlic, N = 60) of the posterior leaflet, among other measures. Demographic data, risk factors, procedure times, hospitalization time, early and long-term mortality as well as Kaplan-Meier survival were analyzed. Results : Age (65.3 vs. 63.1 years) and sex (28.8% female vs. 337.5% female) did not differ significantly, and the EuroSCORE was significantly higher in the InvPlic group (6.46 ± 2.75) than in the QuadRes group (5.68 ± 3.1). Procedural times did not differ for cardiopulmonary bypass, and were as follows: InvPlic 136 ± 44 min; QuadRes 140 ± 48 min; X-Clamp: InvPlic 91 ± 31 min; QuadRes 90 ± 32 min. Hospitalization time was slightly but insignificantly lower in the InvPlic group (15.5 days) than in the QuadRes group (16.1 days). Early mortality (5.08% vs. 8.33%) and re-do procedures (1.69% InvPlic; 6.67% QuadRes) did not differ significantly. However, long-term mortality was significantly lower in the InvPlic group (15.25% vs. 32.32%, p = 0.029). Conclusions : Among the surgical measures for the posterior leaflet, inverse plication appears to be non-inferior to quadrangular resection in unselected all-comer patients. Long-term results and absence of re-do procedures indicate very good stability. Thus, inverse plication not only allows correction of PML, but is also completely safe in the long term and can replace quadrangular resection, especially in patients where a reduction in technical challenges and procedure duration is desired., Competing Interests: The authors declare no conflicts of interest.

Objective: Mitral valve reconstruction (MVR) is one of the cardiosurgical procedures which cannot be substituted by any intervention owing to the quality of the quasi-anatomical, physiological repair. However, technique and strategies have changed over the years. We looked at procedural characteristics and outcome in an all-comer, non-selected cohort of patients., Methods: 738 out of 1.977 patients were retrospectively analyzed receiving MVR with and without concomitant procedures. The cohort was divided into three periods. P1: 2004-2009 (134 pts.); P2: 2010-2014 (294 pts.), and P3: 2015-2019 (310 pts.)., Results: Early mortality increased from P1 to P2 and decreased from P2 to P3 (9% P1, 13% P2, 10% P3). All patients received an annuloplasty-ring. In P1 resection measures dominated. In P3 artificial chordae were dominant. Age, BMI, and risk scores correlated with early mortality. Survival rates were 66% (5-years), 55% (10-years), 44% (15-years) in P1, 63% (5-years), 50% (10-years) in P2, and 80% (5-years) in P3. Odds ratio for reduced long-term survival were concomitant venous only bypass surgery (10-years 2,701, p = 0.026). 10-year survival was positively influenced by isolated MVR (0.246, p = 0.001), concomitant isolated arterial bypass (IMA) (0.153, p = 0.051), posterior leaflet measure (0.178, p<0.001), and use of artificial chordae (5-years 0.235, p<0.001)., Conclusion: Indication for ring implantation remained mandatory while preference changed alongside improved designs. Procedural characteristics changed from mainly resection maneuvers to predominant use of artificial chordae. Long-term results were negatively influenced by co-morbidities and positively influenced by posterior leaflet repair and artificial chordae. MVR underwent a qualitative evolution and remains a valuable cardiosurgical procedure., Competing Interests: The authors have declared that no specific interests exist.

Functionally graded NiTi structures benefit from the combination of the smart properties of NiTi and those of functionally graded structures. This article provides experimental data for thermomechanical deformation behaviour of microstructurally graded, compositionally graded and geometrically graded NiTi alloy components, related to the research article entitled "Functionally graded shape memory alloys: design, fabrication and experimental evaluation" (Shariat et al., 2017) [1]. Stress-strain variation of microstructurally graded NiTi wires is presented at different heat treatment conditions and testing temperatures. The complex 4-way shape memory behaviour of a compositionally graded NiTi strip during one complete thermal cycle is demonstrated. The effects of geometrical design on pseudoelastic behaviour of geometrically graded NiTi plates over tensile loading cycles are presented on the stress-strain diagrams.