X-linked Emery–Dreifuss muscular dystrophy (EDMD1) is a rare early-onset myopathy, affecting 1/400.000 individuals, characterized by humeroperoneal weakness, contractures and cardiac involvement. EDMD1 natural history has been poorly investigated, with most of the studies including only a few patients. The aim of the study was to investigate the clinical and molecular features in a large Italian cohort of EDMD1. We retrospectively collected data of 38 genetically defined EDMD1 males (16 members of 6 families, and 22 sporadic cases) and 10 female carriers, from 14 referral neuromuscular centers in Italy. Patients were included only if showing detectable muscle weakness or contractures at the neurological examination. Mean age at onset of patients was 12.0 ± 3.4 years (range 2–61). Among them 32 (84.2
We achieve new results on skew polynomial rings and their quotients, including the first explicit example of a skew polynomial ring where the ratio of the degree of a skew polynomial to the degree of its bound is not extremal. These methods lead to the construction of new (not necessarily associative) division algebras and maximum rank distance (MRD) codes over both finite and infinite division rings. In particular, we construct new non-associative division algebras whose right nucleus is a central simple algebra having degree greater than 1. Over finite fields, we obtain new semifields and MRD codes for infinitely many choices of parameters. These families extend and contain many of the best previously known constructions.
With increasing miniaturization and rising power densities of electronic devices, robust thermal management strategies are inevitable for ensuring operational stability. In the pursuit of next-generation thermal management solutions for high-density electronics, impinging jet flow (IJF) systems integrated with metal foam (MF) have emerged as a promising technique. This study investigates the interplay between pore density (measured in pores per inch or PPI), foam thickness, and flow dynamics to identify configurations that deliver optimal thermal performance. By analyzing the coupled effects of these parameters, the work aims to enhance convective heat transfer while minimizing adverse pressure losses. The investigation utilizes several key performance metrics: the average Nusselt number (Nu_avg), Colburn j-factor, Performance Enhancement Coefficient (PEC), pumping power (PP), and dimensionless power number (Np), to comprehensively assess proficient heat transfer in conjunction with hydraulic efficiency. Results reveal that lower PPI structures and increased foam thickness significantly enhance heat transfer, as evidenced by elevated Nusselt numbers resulting from intensified flow interaction and turbulence. Conversely, substrate disc plates with lower thermal conductivity exhibit reduced cooling efficiency. An empirical correlation of the form Nuavg = c1Rec2 is proposed to capture the underlying heat transfer behavior. The findings offer actionable insights into the design of compact, high-performance cooling solutions tailored for next-generation electronic systems.
Effective heat dissipation is essential for cooling power-intensive chips and densely packed electronics with significant heat output such as those used in data centers. This study explores the hybrid thermal management strategies that combine the use of impinging jet flow (IJF) and high-porosity metal foam (MF) heat sinks to enhance convective heat transfer. Unlike conventional jet cooling systems, the integration of metal foam introduces a highly conductive, porous medium that amplifies surface area, promotes flow mixing, and accelerates thermal diffusion - resulting in 1-2 times higher heat transfer compared to clear cases (CC). A 2D axisymmetric numerical model is developed in ANSYS Fluent using the Reynolds-Averaged Navier-Stokes (RANS) equations with the standard k-epsilon turbulence model. The setup features a single circular nozzle, aluminum target plate, aluminum metal foams with air as a cooling fluid. Key parameters including nozzle-to-plate spacing (IH = 2.8-8.5), Peclet number (Pe = 2200-17,000), and foam porosity (epsilon = 0.90-0.95) - are systematically varied. The findings indicate that minimizing porosity and internal heating (IH) substantially enhances heat transfer performance. A novel correlation for average Nusselt number (Nu) has been developed, accompanied by an enhancement factor that quantifies the thermal improvement across the analyzed configurations. This work provides a robust framework for optimizing hybrid cooling systems and can be extended to explore alternative working fluids, foam geometries, and transient thermal loads in future studies.
This study investigates the thermal performance of nanoPCM emulsions (nanoPCMEs) as working fluids in parallel plate thermal energy storage system, comparing two configurations: solid aluminum walls and aluminum profile walls filled with PCM + metal foam. Three distinct nanoPCM emulsions were evaluated against pure water as a base fluid. The experimental results demonstrated superior convection heat transfer performance for all nanoPCMEs compared to pure water. In the solid aluminum wall configuration, maximum thermal energy storage reached approximately 900 kJ, with 2.0 wt% nanoPCME achieving this level twice as fast as pure water. The PCM + metal foam configuration exhibited enhanced performance, storing up to 2250 kJ of thermal energy due to PCM's high latent heat, reaching maximum storage 1.6 times faster than pure water. Notable improvements in heat transfer were observed, with nanoPCME achieving the highest average Nusselt numbers across all configurations. Maximum enhancements in Nusselt number were 34.5 % and 41.9 % for solid wall and PCM + metal foam configurations, respectively, using 2.0 wt% nanoPCME. These findings demonstrate the significant potential of nanoPCMEs for improving thermal energy storage systems and thermal control applications.
