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Background: Accurate measurements of flow and ventricular volume and function are critical for clinical decision-making in cardiovascular medicine. Cardiac magnetic resonance (CMR) is the current gold standard for ventricular functional evaluation but is relatively expensive and time-consuming, thus limiting the scale of clinical applications. New volumetric acquisition techniques, such as four-dimensional flow (4D-flow) and three-dimensional volumetric cine (3D-cine) MRI, could potentially reduce acquisition time without loss in accuracy; however, this has not been formally tested on a large scale. Methods: 4DCarE (4D-flow MRI for cardiovascular evaluation) is a prospective, multi-centre study designed to test the non-inferiority of a compressed 20 min exam based on volumetric CMR compared with a conventional CMR exam (45–60 min). The compressed exam utilises 4D-flow together with a single breath-hold 3D-cine to provide a rapid, accurate quantitative assessment of the whole heart function. Outcome measures are (i) flow and chamber volume measurements and (ii) overall functional evaluation. Secondary analyses will explore clinical applications of 4D-flow-derived parameters, including wall shear stress, flow kinetic energy quantification, and vortex analysis in large-scale cohorts. A target of 1200 participants will enter the study across three sites. The analysis will be performed at a single core laboratory site. Pilot Results: We present a pilot analysis of 196 participants comparing flow measurements obtained by 4D-flow and conventional 2D phase contrast, which demonstrated moderate–good consistency in ascending aorta and main pulmonary artery flow measurements between the two techniques. Four-dimensional flow underestimated the flow compared with 2D-PC, by approximately 3 mL/beat in both vessels. Conclusions: We present the study protocol of a prospective non-inferiority study of a rapid cardiac MRI exam compared with conventional CMR. The pilot analysis supports the continuation of the study. Study Registration: This study is registered with the Australia and New Zealand Clinical Trials Registry (Registry number ACTRN12622000047796, Universal Trial Number: U1111-1270-6509, registered 17 January 2022—Retrospectively registered). [ABSTRACT FROM AUTHOR]

One of the most common problems faced by briquette machine users in the industry is the failure of the cast iron housing unit of the UCF-216 bearings, to which the main shaft of the briquette machine is attached. In this study, the failure mechanism of a cast iron housing unit of a UCF-216 bearing broken during operation in a briquette machine was analyzed in order to develop a solution to the problem. Failure was occurring in the bolt hole areas of the housing unit. First of all, spectral analysis was performed and it was determined that the housing unit was grey cast iron. Then, the macrostructures of both unused and damaged housing units were examined. Some casting defects were detected in the bolt hole areas of the unused housing unit. It was also learned that during the assembly of the UCF-216 to the briquette machine, no torque meter was used while the bolts were tightened. In order to understand the effect of possible overtightening of the bolts, the system was modelled as a 3D solid. This model was exported to the finite element software and different bolt pretensions were applied considering the stresses created by the bolt tightening forces on the housing unit. As a result, it was understood that if the ratio of the stress caused by the axial bolt tightening force in the UCF-216 bearing unit to the yield stress of the UCF-216 housing unit is above 50%, fatigue failure will occur. [ABSTRACT FROM AUTHOR]

Although the spark plasma sintering (SPS) method is a very advantageous technque in many aspects, the inability to clearly read the temperature formed on the material during sintering and heterogeneous temperature distributions are the biggest problems of this process. Therefore, it is a common situation that samples taken from different regions of the produced material have different densities and mechanical properties. In this study, the temperature distributions, current density and joule heating effect of the entire setup consisting of the alumina (Al2O3) sample to be sintered, inconel electrodes, graphite dies, punches and spacers, as well as the critical regions in this setup, are modeled by using finite element software. According to the results, the temperature is maximum at the centre of the Al2O3 sample and the temperature gradient along its radius is 22.4°C. The temperature difference between the inner wall of the hole which is opened in the graphite mold to measure the sintering temperature and the centre of the Al2O3 sample is around 40°C. In addition, during the SPS process, Al2O3 is not heated directly by the joule effect and the temperature gradient in the sample occurs due to mold surface radiation. [ABSTRACT FROM AUTHOR]

Aluminum is one of the most important materials with various usages. It has important features such as lightness, corrosion resistance, the compatibility with heat treatment, formability and affordable price. Conversely, Al-Cu alloys are extensively employed in the aerospace industry because of their exceptional combination of high specific strength and excellent machining characteristics. In this alloy, copper increases the strength of the material as it forms intermetallic compounds with alloying elements. Moreover, precipitation hardening is possible by dissolving copper in aluminum in the solid phase. This study examines the microstructure and mechanical properties of composites with matrix of Al-Cu alloys. To accomplish this, the initial step involved melting the Al-Cu alloy at a temperature of 800 °C, followed by the addition of 0.3% and 0.5% steel powder by weight into the molten mixture. The Al-Cu melt mixed at 300 rpm for 10 minutes, was controlled with Aluflux and degassing tablets and the resulting mixture was cast into a steel mold. The Al-Cu alloys of the heat treatment were fulfilled at 500 degrees for 2 h and then cooled in water. The aging process of T6 was carried out by keeping it in an annealing furnace at 150 and 200 degrees for 1 and 3 h. Following the manufacturing procedures, the samples were polished and etched to facilitate microstructural studies. The obtained Vickers hardness values were analyzed with the Taguchi method and the results were evaluated. The maximum hardness value recorded in this study was 263.86 HV. The Al-Cu casting alloy exhibited a relatively higher density, indicating lower porosity, when a synergistic combination of 0.3% steel powder additive and a 1-hour aging time was applied. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the possible link between hematological and atherogenic indices reflecting inflammation and cardiovascular risk and exfoliation syndrome (XFS) and exfoliation glaucoma (XFG). Materials and Methods: This study included a total of 83 participants (29 XFS, 25 XFG, and 29 healthy controls) who were scheduled for routine cataract surgery. Blood sampling was performed from the individuals and complete blood count (CBC), C-reactive protein (CRP), uric acid (UA), and serum lipids were measured. Neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio (MLR), monocyte/high-density lipoprotein cholesterol (HDL-c) ratio (MHR), and platelet/lymphocyte ratio (PLR) were also calculated. Examined parameters were compared statistically. Results: Statistically significant higher white blood cells, neutrophil count, UA and triglyceride (TG) levels were determined in the XFG group. NLR and MLR were significantly higher in the XFS and XFG groups compared to the control group. MHR was significantly higher in the XFG group than the control group. Lymphocyte count was significantly lower in the XFS and XFG groups compared to the control group. HDL-c was significantly lower in the XFG group compared to the other two groups. Furthermore, receiver operating curve analysis revealed that lymphocyte count, NLR, MLR, MHR, and HDL-c had significant predictive value for XFS, and NLR, MHR, and HDL-c for XFG. Conclusion: In the light of current knowledge, XFS is a multisystem entity. This study results revealed that there was a link between XFS/XFG and hematological and atherogenic parameters reflecting inflammation and cardiovascular risk and these parameters may be important in the follow-up of XFS/XFG and related diseases. [ABSTRACT FROM AUTHOR]

High manganese steel is a metallic material that has a very important commercial value especially in heavy industry and stands out with its features such as high wear resistance, and deformation hardening. In order to further improve the properties of these steels, many studies have reported on adding various elements to their structures. However, there is still a lack of understanding of the relationship between the wear mechanism and strain hardening due to changes in the microstructure of high manganese steel during the wear process and the complex carbides it contains. In this study, Al5Ti1B (1% wt.), which is also used as a grain refiner in the metallurgy industry, was added. After melting, casting, and other production processes, test samples were prepared for microstructure analysis, hardness, and wear tests. It was observed that there were carbide phases at the grain boundaries of the test sample, and the hardness value was determined to be 254 HV ± 14. The friction coefficients at 5 and 10 N loads increased by approximately 17.9% and 9.8%, respectively, by increasing the 500 m sliding distance to 1000 m. The effects of strain hardening and brittleness were also observed in the microstructure examinations after the wear test. In addition, a decrease in weight loss was observed, indicating that some deformation hardening occurred in the specimen during wear. [ABSTRACT FROM AUTHOR]