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As the main precursor of cardiovascular diseases, atherosclerosis is a complex inflammatory disorder that preferentially occurs in stenotic, curved, and branched arterial regions. Although various in vitro models are established to understand its pathology, reconstructing the native atherosclerotic environment that involves both co‐cultured cells and local turbulent flow singling remains challenging. This study develops an arterial construct via in‐bath coaxial cell printing that not only facilitates the direct fabrication of three‐layered conduits with tunable geometry and dimensions but also maintains structural stability. Functional vascular tissues, which respond to various stimulations that induce endothelial dysfunction, are rapidly generated in the constructed models. The presence of multiple vascular tissues under stenotic and tortuous turbulent flows allows the recapitulation of hallmark events in early atherosclerosis under physiological conditions. Furthermore, the fabricated models are utilized to investigate the individual and synergistic functions of cell co‐culture and local turbulent flows in regulating atherosclerotic initiation, as well as the dose‐dependent therapeutic effect of atorvastatin. These outcomes suggest that the constructed atherosclerotic model via a novel fabrication strategy is a promising platform to elucidate the pathophysiology of atherosclerosis and seek effective drugs and therapies. [ABSTRACT FROM AUTHOR]

Abstract: The frequency dependence of dielectric properties of SrTiO3–Pt (platinum) composites has been investigated. The SrTiO3–Pt composites sintered at 1300°C for 2h was prepared by using conventional ceramic fabrication method. The dense metallodielectric composites without chemical reaction between SrTiO3 and Pt during sintering process were obtained. The relative permittivity (ɛ r) of SrTiO3–Pt composites was increased with increase of amount of Pt. The maximum ɛ r of 2150 at 1MHz was obtained for the composite of SrTiO3–27vol.% Pt. Moreover, the SrTiO3–Pt composites exhibited high values of ɛ r at low frequencies than at high frequencies due to space charge polarization. The loss tangent (tan δ) of SrTiO3–Pt composites increased with increasing amount of Pt, and decreased with increasing frequency up to 1MHz. However, the tan δ of SrTiO3–Pt composites was significantly increased at microwave frequency due to abrupt increase of ac conductivity of composite. [Copyright &y& Elsevier]

Abstract: Computer Aided Design (CAD) of a microstrip slit-tetragonal resonator with a gap located in the middle of one of its edges has been made, using Finite Difference Time Domain (FDTD). A piece of sintered ferroelectric BaTiO3 with tetragonal crystal structure was placed on the gap of this resonator and was thermally excited using a halogen lamp. Significant change of S-parameters of the device was found in the vicinity of the Curie temperature (T c) of BaTiO3 for the fundamental resonant mode (n =1), as it is expected from simulations. Electric near field calculations verified the previous behavior. [Copyright &y& Elsevier]

Abstract: The effect of B2O3 or CuO addition on the microwave dielectric properties of 0.96MgTiO3–0.036SrTiO3 (MST0.036) ceramics sintered at temperatures ranging from 1070 to 1170°C has been investigated. Addition of B2O3 successfully reduced the sintering temperature of MST0.036 ceramics from 1270 to 1170°C. When 2wt% B2O3 was added to MST0.036 ceramics, sintered at 1170°C for 2h, the apparent density of MST0.036 ceramics significantly increased from 3.57 to 3.89g/cm3 due to liquid phase sintering. However, increase of B2O3 contents slightly deteriorated the Qf value of MST0.036 ceramics. In the MST0.036-CuO system, secondary phase was formed by reaction between MST0.036 and CuO, so the Qf value of MST0.036 ceramics steeply decreased. The MST0.036 sample with 2wt% of B2O3, sintered at 1170°C for 2h, was measured to have good microwave dielectric parameters: ɛ r of 19, Qf value of 75,300GHz (at 9GHz) and τ f of −8.9ppm/°C. [Copyright &y& Elsevier]

Vascular diseases are complex conditions orchestrated by multiple factors, including cellular components, biochemical stimuli, and mechanical forces. Despite the advancement of numerous therapeutic approaches, the global mortality associated with the diseases continues to escalate owing to a lack of understanding of the underlying pathologies. Tissue engineering and computational strategies have been recently developed to investigate diseased blood vessels from multifactorial perspective, enabling more accurate prediction of disease progression and opening new avenues for preclinical advances. This review focuses on in vitro and in silico blood vessel models to elucidate the pathomechanisms of vascular diseases. Following a discussion of biofabrication and computational modeling strategies, the recent research that utilizes the models of various blood vessel diseases, such as atherosclerosis, aneurysms, varicose veins, and thrombosis, are introduced. Finally, current breakthroughs, existing challenges, and outlooks in the field are described., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)