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ObjectivesThis study sought to report full 1-year results, detailed magnetic resonance imaging analysis, and determinants of efficacy in the prospective, randomized, controlled CADUCEUS (CArdiosphere-Derived aUtologous stem CElls to reverse ventricUlar dySfunction) trial.BackgroundCardiosphere-derived cells (CDCs) exerted regenerative effects at 6 months in the CADUCEUS trial. Complete results at the final 1-year endpoint are unknown.MethodsAutologous CDCs (12.5 to 25 × 10(6)) grown from endomyocardial biopsy specimens were infused via the intracoronary route in 17 patients with left ventricular dysfunction 1.5 to 3 months after myocardial infarction (MI) (plus 1 infused off-protocol 14 months post-MI). Eight patients were followed as routine-care control patients.ResultsIn 13.4 months of follow-up, safety endpoints were equivalent between groups. At 1 year, magnetic resonance imaging revealed that CDC-treated patients had smaller scar size compared with control patients. Scar mass decreased and viable mass increased in CDC-treated patients but not in control patients. The single patient infused 14 months post-MI responded similarly. CDC therapy led to improved regional function of infarcted segments compared with control patients. Scar shrinkage correlated with an increase in viability and with improvement in regional function. Scar reduction correlated with baseline scar size but not with a history of temporally remote MI or time from MI to infusion. The changes in left ventricular ejection fraction in CDC-treated subjects were consistent with the natural relationship between scar size and ejection fraction post-MI.ConclusionsIntracoronary administration of autologous CDCs did not raise significant safety concerns. Preliminary indications of bioactivity include decreased scar size, increased viable myocardium, and improved regional function of infarcted myocardium at 1 year post-treatment. These results, which are consistent with therapeutic regeneration, merit further investigation in future trials. (CArdiosphere-Derived aUtologous stem CElls to reverse ventricUlar dySfunction [CADUCEUS]; NCT00893360).

BackgroundEpicardial injection of heart-derived cell products is safe and effective post-myocardial infarction (MI), but clinically-translatable transendocardial injection has never been evaluated. We sought to assess the feasibility, safety and efficacy of percutaneous transendocardial injection of heart-derived cells in porcine chronic ischemic cardiomyopathy.Methods and resultsWe studied a total of 89 minipigs; 63 completed the specified protocols. After NOGA-guided transendocardial injection, we quantified engraftment of escalating doses of allogeneic cardiospheres or cardiosphere-derived cells in minipigs (n = 22) post-MI. Next, a dose-ranging, blinded, randomized, placebo-controlled ("dose optimization") study of transendocardial injection of the better-engrafting product was performed in infarcted minipigs (n = 16). Finally, the superior product and dose (150 million cardiospheres) were tested in a blinded, randomized, placebo-controlled ("pivotal") study (n = 22). Contrast-enhanced cardiac MRI revealed that all cardiosphere doses preserved systolic function and attenuated remodeling. The maximum feasible dose (150 million cells) was most effective in reducing scar size, increasing viable myocardium and improving ejection fraction. In the pivotal study, eight weeks post-injection, histopathology demonstrated no excess inflammation, and no myocyte hypertrophy, in treated minipigs versus controls. No alloreactive donor-specific antibodies developed over time. MRI showed reduced scar size, increased viable mass, and attenuation of cardiac dilatation with no effect on ejection fraction in the treated group compared to placebo.ConclusionsDose-optimized injection of allogeneic cardiospheres is safe, decreases scar size, increases viable myocardium, and attenuates cardiac dilatation in porcine chronic ischemic cardiomyopathy. The decreases in scar size, mirrored by increases in viable myocardium, are consistent with therapeutic regeneration.

The influence of AA7075 grain refinement, graphene reinforcement and SiC addition on the mechanical and tribological properties of hybrid composites is examined in the current work. The composites are synthesized using the powder metallurgy technique and reinforced with different mass fractions of graphene in micro, nano, bimodal and hybrid structures. XRD is used to study the structural behaviour of a phase lattice arrangement with grains of different sizes and TEM is used to characterize the dispersion of the constituents in the composites. Properties notably density, hardness, compressive strength and wear have all been investigated. The density of the composite increased with a finer nAA7075 matrix, and the addition of SiC further enhanced the density of the hybrid composite, despite the fact that the density of the composite reduced as more graphene was added. The hybrid composite provided better hardness and compressive strength, and the properties progressively started to improve with the inclusion of graphene particles. The SiC particles of hybrid composite prevent the surface material from deteriorating, reducing adhesive wear and delamination. [ABSTRACT FROM AUTHOR]

Partition dimension problems involve dividing a graph's vertex set into a minimum number of disjoint sets so that each vertex is different with respect to the representation from each disjoint set. As a result of the development of this method, a number of applications have arisen in a number of fields such as drug design, navigation of robots, pattern recognition, and image processing. In this paper, we have calculated the partition dimension of oxide and zigzag benzenoid networks, and the subdivision of benzenoid hydrocarbon and triangular benzene networks. [ABSTRACT FROM AUTHOR]

The current research work presents the synthesis and characterization of graphene-reinforced bimodal (Bi) AA7075 matrix composite by powder metallurgy route. The bimodal AA7075 alloy is optimized with micro (µ)- and nano (n)-crystalline grain morphologies in order to achieve better strength while retaining the vital minimal ductility. The effect of milling duration on grain size and particle uniformity is characterized by XRD and TEM. Density, hardness, compressive strength, and wear rate of bimodal composites are investigated. The addition of optimized 20% µAA7075 particles to nAA7075 particles provides the minimum necessary ductility in bimodal composites while increasing the interplanar space between the phase lattices. The use of graphene up to 0.75% enhanced wear resistance in comparison with the other compositions. The existence of both adhesive mechanisms and abrasive wear further reveals the plasticity of the bimodal composites, which are ideally suitable for engineering applications requiring greater strength and reliability. [ABSTRACT FROM AUTHOR]

The brushless direct current motors have gained popularity among the emerging technologies due to their increased efficiency, speed of operation, and density of flux. This paper presents a novel technique for controlling the speed of the brushless direct current motor by using hybrid algorithms. The Particle Swarm Optimization (PSO) algorithm is combined with the Takagi Sugeno adaptive fuzzy interference system and gravitational search algorithms to analyze the speed control of the brushless DC electric motor (BLDC) motors. The proposed model has designed multiple outputs prototype for BLDC motor with Takagi Sugeno fuzzy logic. Since the adaptive fuzzy logic system has three outputs, the final output is evaluated as the average value of all the outputs using the LMS algorithm. The speed control of the Brushless DC motor has also been analyzed using a combination of the gravitational search algorithm and the PSO algorithm. The motor parameters taken under consideration for the analysis have been tabulated. The different results obtained at the end of this study have been demonstrated through graphs and tables. [ABSTRACT FROM AUTHOR]

The fifth-generation SAPIEN 3 Ultra Resilia valve (S3UR) incorporates several design changes as compared with its predecessors, the SAPIEN 3 (S3) and SAPIEN 3 Ultra (S3U) valves, including bovine leaflets treated with a novel process intended to reduce structural valve deterioration via calcification, as well as a taller external skirt on the 29-mm valve size to reduce paravalvular leak (PVL). The clinical performance of S3UR compared with S3 and S3U in a large patient population has not been previously reported. The aim of this study was to compare S3UR to S3/S3U for procedural, in-hospital, and 30-day clinical and echocardiographic outcomes after transcatheter aortic valve replacement (TAVR). Patients enrolled in the STS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry between January 1, 2021, and June 30, 2023, who underwent TAVR with S3UR or S3U/S3 valve platforms were propensity-matched and evaluated for procedural, in-hospital, and 30-day clinical and echocardiographic outcomes. 10,314 S3UR patients were propensity matched with 10,314 patients among 150,539 S3U/S3 patients. At 30 days, there were no statistically significant differences in death, stroke, or bleeding, but a numerically higher hospital readmission rate in the S3UR cohort (8.5% vs 7.7%; P = 0.04). At discharge, S3UR patients exhibited significantly lower mean gradients (9.2 ± 4.6 mm Hg vs 12.0 ± 5.7 mm Hg; P < 0.0001) and larger aortic valve area (2.1 ± 0.7 cm2 vs 1.9 ± 0.6 cm2; P < 0.0001) than patients treated with S3/S3U. The 29-mm valve size exhibited significant reduction in mild PVL (5.3% vs 9.4%; P < 0.0001). S3UR TAVR is associated with lower mean gradients and lower rates of PVL than earlier generations of balloon expandable transcatheter heart valve platforms. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper describes about the design, fabrication and flow simulation of a choked flow nozzle which is used to supply constant mass flow rate to the air heater which can provide supersonic conditions for Supersonic Engine Test Facilities. The test facility is considered to be capable of delivering working gas at 5-20 kg/s flow rate, stagnation temperature at 800-2200 K and stagnation pressure at 8-40 bar to the inlet of combustion chamber of the engine for specified duration. The outlet condition for the choked nozzle is considered to be known and the required inlet pressure for the nozzle has to be found out. This converging nozzle should be capable of providing constant mass flow rate. [ABSTRACT FROM AUTHOR]