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Background: Transcatheter aortic valve implantation is experiencing continued growth as an option for the treatment of aortic stenosis. With larger numbers of procedures being performed on lower risk and younger patients, there is increased scrutiny on valve durability. Leaflet stresses and potential damage have a significant role to play in this regard. Predictions of leaflet stresses have so far focused on either fluid-structure interaction simulations of blood flow through the prosthesis or, crimping simulations using a cylindrical surface. However, in reality, when a compression loading system (CLS) is used in the crimping of self-expanding valves, this could result in different stresses in the valve leaflets relative to those that might occur in crimping with a cylindrical surface.Method: A full model of a CoreValve Evolut Pro (Medtronic, Minneapolis, MN, USA) device was developed, comprising the frame, skirt and leaflets along with a representative model for the CLS as used in clinical practice. The full device was crimped to a final diameter of 18 Fr using the CLS model and the distribution and intensity of leaflet stresses was assessed. A similar assessment of leaflet stresses was also performed for crimping using radial displacement of a cylindrical surface. Comparison of the predicted leaflet stresses between the two models was undertaken, alongside a comparison of the stresses produced when dynamically loading the leaflets after deployment of the valve.Results: Both the CLS and cylinder crimping methods produced higher average and peak stresses on the leaflets compared to those produced during leaflet loading. The peak von Mises stresses for CLS crimping, cylinder crimping, and leaflet loading were 3.42 MPa, 3.92 MPa, and 1.77 MPa respectively. The leaflet folding pattern between the CLS crimping and cylinder crimping methods were different, resulting in different high stress locations on the leaflets. However, the average stress magnitude at the final crimped stage between the two crimping methods were similar.Conclusions: High fidelity simulations of crimping and expansion of a complete CoreValve Evolut Pro model using a compression loading system model have been performed, wherein the results showed that peak leaflet stresses in the crimped valve were approximately twice as high as the maximum leaflet stresses under dynamic loading. This finding has significant implications for device durability due to the high stresses and possible damage they might inflict on the leaflets. It was also found that crimping using a compression loading system versus a simpler cylindrical surface produced different folding patterns and stress distributions. However, for future studies that are not concerned with accurately capturing the leaflet folding patterns and stresses throughout the crimping process, crimping via a cylindrical surface can be used instead of simulating the full CLS model.

Chronic obstructive pulmonary disease (COPD) is an umbrella term used to define a collection of inflammatory lung diseases that cause airflow obstruction and severe damage to the lung parenchyma. This study investigated the robustness of image-registration-based local biomechanical properties of the lung in individuals with COPD as a function of Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage. Image registration was used to estimate the pointwise correspondences between the inspiration (total lung capacity) and expiration (residual volume) computed tomography (CT) images of the lung for each subject. In total, three biomechanical measures were computed from the correspondence map: the Jacobian determinant; the anisotropic deformation index (ADI); and the slab-rod index (SRI). CT scans from 245 subjects with varying GOLD stages were analyzed from the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS). Results show monotonic increasing or decreasing trends in the three biomechanical measures as a function of GOLD stage for the entire lung and on a lobe-by-lobe basis. Furthermore, these trends held across all five image registration algorithms. The consistency of the five image registration algorithms on a per individual basis is shown using Bland–Altman plots.

International Conference on Building Envelope Systems and Technologies – ICBEST is the premier conference for attendees to benefit from the cutting edge information on building envelope systems and technologies. ICBEST is a worldwide forum for building envelope architecture and engineering. It provides information exchange, networking, and discussions of recent developments and their application thus bridging the gap between architects, designers, engineers, manufacturers, and researchers

The purpose of this work was to analyse the energy productivity and efficiency of agricultural enterprises growing poppy. The number of enterprises investigated in the study was determined from a stratified random sample of 87, the data is from 2019, and the study was conducted in Turkey. All inputs and outputs used in poppy production were obtained by multiplying energy equations with conversion coefficients in determining the energy use of the enterprises. Data Envelopment Analysis (DEA) method was employed to calculate the technical, pure-technical, and scale efficiency of poppyproducing enterprises. Poppy energy inputs consisted of the use of human labour, machinery, fertilizer, pesticides, seeds, water, and fuel. The poppy capsule yield per unit area was regarded as the energy output. In the end, 40.23% of the total energy input in poppy production consisted of direct and 59.77% indirect energy. Non-renewable energy consumption (88.70%) was found to be rather high in the research area. Therefore, the use of chemical fertilizers and fuels, which are non-renewable energy sources, must be lessened for poppy plant production. The energy efficiency was found to be 0.08 in poppy production. According to this result, the production systems of the enterprises producing poppy are sufficient and energy is used efficiently. The specific energy value in the enterprises was calculated as 11.95 MJ kg-1 and the Technical Efficiency (TE) was calculated as 0.683. Producers produce at the same level with 68.3% of their capital, and 31.7 % saving. [ABSTRACT FROM AUTHOR]

Bu çalışma, BAP, IBA ve IAA hormonlarının 50 ve 100 ppm dozlarının Melissa officinalis L. (Oğulotu) bitkisinin büyüme ve biyokimyasal parametreleri üzerindeki etkilerini araştırmak amacıyla gerçekleştirilmiştir. Deneme, sera koşullarında “Tam Şansa Bağlı Tesadüf Parselleri” deneme desenine göre üç tekrar ile yapılmıştır. Çalışmada; fide boyu, kök uzunluğu, fide yaş ve kuru ağırlıkları, kök yaş ve kuru ağırlıkları, klorofil a ve b, toplam karotenoidler, toplam fenolik maddeler ve antioksidan aktiviteler (CUPRAC ve FRAP) değerlendirilmiştir. Çalışma sonucunda; kök yaş ağırlığı dışındaki büyüme parametrelerinde hormon uygulamalarının kontrole göre önemli etkisinin olduğu, fide boyu, yaş, kuru ağırlıkları ile kök kuru ağırlıklarında en yüksek sonuçlara IBA50 dozunda ulaşıldığı, kök uzunluğunda ise en yüksek değere BAP100 uygulamasında ulaşıldığı görülmüştür. Klorofil a, b ve total karotenoid parametrelerinde en yüksek değerler kontrol uygulamalarından, en yüksek antioksidan aktivite (FRAP) BAP100, en yüksek toplam fenolik madde miktarı ise IBA100 uygulamalarında ölçülmüştür.

Bu çalışmada "Sağlık Çalışanlarında Mutsuzluk Negatif Örgütsel Davranışlar" kitabı incelenmiştir.

Usable/rentable floor areas are crucial for the building owners in reinforced concrete (RC) tall buildings. To address this issue, concrete‐encased (CE) or concrete‐filled (CF) composite columns are proposed as alternative vertical load carrying elements by providing the required strength and ductility, but with smaller dimensions. Comparing the performance of columns with different configurations can be done using moment (M)‐axial load (N) interaction curves. This paper summarizes the approaches proposed by Eurocode 4 and AISC 360‐16 for both types of composite columns, presenting simplified and true curves for a specific class of sections. Two case studies involving hybrid RC tall buildings in Istanbul, which utilized composite columns, are presented along with a comparison with steel‐concrete composite and RC solutions. Numerical results indicate that employing steel‐concrete composite columns resulted in approximately 24% reduction in total cross‐sectional areas for one of the case studies, leading to increased usable/rentable areas. Additionally, concrete‐encased and concrete‐filled composite columns exhibited similar performance in terms of axial load‐moment capacities. The impact of longitudinal rebar ratios is also investigated, revealing that the AISC 360‐16 approach yields smaller bending moments and compression capacities compared to Eurocode 4 due to the significant strength reduction factor considered in calculating the concrete contribution in composite sections. [ABSTRACT FROM AUTHOR]

Objective: Although lipomas are the most common benign soft tissue tumors, they are rarely found in the hand and are exceptionally rare on the fingers. Therefore, the purpose of this study was to investigate lipomas in atypical locations to aid in the differential diagnosis of finger tumors. Methods: We retrospectively examined a cohort of 20 patients who were diagnosed with lipomas on the fingers. The diagnosis was made through clinical and imaging examinations. Surgical intervention was based on symptoms such as pain, paresthesias, functional impairment, or aesthetic concerns. Results: Lipomas were more likely to be located on the third finger of the right hand, and most common pathological subtype was fibrolipoma. One giant lipoma was observed. Conclusion: Lipomas on the fingers are rare occurrences that typically affect females, and the optimal surgical treatment involves complete removal of the tumor to achieve definitive healing. Despite their rarity, clinicians should consider lipomas in the differential diagnosis of soft tissue tumors in the hand.