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The recent development of accurate and efficient semilocal density functionals on the third rung of Jacob's ladder of density functional theory, such as the revised regularized strongly constrained and appropriately normed (r2SCAN) density functional, could enable rapid and highly reliable prediction of the elasticity and temperature dependence of thermophysical parameters of refractory elements and their intermetallic compounds using the quasi-harmonic approximation (QHA). Here, we present a comparative evaluation of equilibrium cell volumes, cohesive energy, mechanical moduli, and thermophysical properties (Debye temperature and thermal expansion coefficient) for 22 transition metals using semilocal density functionals, including the local density approximation (LDA), Perdew–Burke–Ernzerhof (PBE) and PBEsol generalized gradient approximations (GGAs), and the r2SCAN meta-GGA. PBEsol and r2SCAN deliver the same level of accuracies for structural, mechanical, and thermophysical properties. PBE and r2SCAN perform better than LDA and PBEsol for calculating cohesive energies of transition metals. Among the tested density functionals, r2SCAN provides an overall well-balanced performance for reliably computing cell volumes, cohesive energies, mechanical properties, and thermophysical properties of various 3d, 4d, and 5d transition metals using QHA. Therefore, we recommend that r2SCAN could be employed as a workhorse method to evaluate thermophysical properties of transition metal compounds and alloys in high throughput workflows. [ABSTRACT FROM AUTHOR]

Development of microelectronic technology is highly desired to address chip power instability and micro-overheating in highly integrated devices utilizing a single material. For this purpose, we propose an efficient strategy by using a ferroelectric thin film to achieve the multifunction of chip power and thermal management. The Pb0.91La0.06Zr0.8Ti0.2O3 (PLZT) thin films undergo nucleation and growth in the (100) preferred orientation on the LaNiO3 bottom electrode during the layer-by-layer annealing process. The obtained chorogi-like structure with both lamellar and columnar nanocrystals results in a high breakdown strength of 4224 kV cm−1, accompanied by an exceptional recoverable energy storage density (Wrec) of 43.20 J cm−3. A large adiabatic temperature change (ΔT) of 27.25 K (@2000 kV cm−1) is obtained near the depolarization temperature, and the broad temperature span (80% ΔTmax) is larger than 50 °C. Moreover, PLZT thin films demonstrate a pyroelectric coefficient (π) of −145 μC cm−2 K−1 with high temperature stability, whose excellent thermal detection capability is confirmed by the infrared response measurement. Above all, the excellent energy storage, electrocaloric effect and pyroelectric properties of the PLZT thin films make them highly promising to inhibit the damage of abrupt current/voltage and uneven heat dissipation for applications in chip power and thermal management. [ABSTRACT FROM AUTHOR]

Background: Macrophage migration inhibitory factor (MIF) is an important mediator of neuropathology in various central nervous system (CNS) diseases. However, little is known about its inducers for production from the nerve cells, as well as the underlying regulatory mechanism. Injury‐induced HIF‐1α has been shown to exacerbate neuroinflammation by activating multiple downstream target molecules. It is postulated that HIF‐1α is involved in the regulation of MIF following spinal cord injury (SCI). Methods: SCI model of Sprague–Dawley rats was established by cord contusion at T8–T10. The dynamic changes of HIF‐1α and MIF protein levels at lesion site of rat spinal cord were determined by Western blot. The specific cell types of HIF‐1α and MIF expression were examined by immunostaining. Primary astrocytes were isolated from the spinal cord, cultured and stimulated with various agonist or inhibitor of HIF‐1α for analysis of HIF‐1α‐mediated expression of MIF. Luciferase report assay was used to determine the relationship between HIF‐1α and MIF. The Basso, Beattie, and Bresnahan (BBB) locomotor scale was used to assess the locomotor function following SCI. Results: The protein levels of HIF‐1α and MIF at lesion site were significantly elevated by SCI. Immunofluorescence demonstrated that both HIF‐1α and MIF were abundantly expressed in the astrocytes of the spinal cord. By using various agonists or inhibitors of HIF‐1α, it was shown that HIF‐1α sufficiently induced astrocytic production of MIF. Mechanistically, HIF‐1α promoted MIF expression through interaction with MIF promoter. Inhibition of HIF‐1α activity using specific inhibitor markedly reduced the protein levels of MIF at lesion site following SCI, which in turn favored for the functional recovery. Conclusion: SCI‐induced activation of HIF‐1α is able to promote MIF production from astrocytes. Our results have provided new clues for SCI‐induced production of DAMPs, which may be helpful for clinical treatment of neuroinflammation. [ABSTRACT FROM AUTHOR]