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This multicenter retrospective study evaluated the diagnostic performance of a deep learning (DL)-based application for detecting, classifying, and highlighting suspected aortic dissections (ADs) on chest and thoraco-abdominal CT angiography (CTA) scans. CTA scans from over 200 U.S. and European cities acquired on 52 scanner models from six manufacturers were retrospectively collected and processed by CINA-CHEST (AD) (Avicenna.AI, La Ciotat, France) device. The diagnostic performance of the device was compared with the ground truth established by the majority agreement of three U.S. board-certified radiologists. Furthermore, the DL algorithms time to notification was evaluated to demonstrate clinical effectiveness. The study included 1303 CTAs (mean age 58.8 ± 16.4 years old, 46.7% male, 10.5% positive). The device demonstrated a sensitivity of 94.2% [95% CI: 88.8-97.5%] and a specificity of 97.3% [95% CI: 96.2-98.1%]. The application classified positive cases by the AD type with an accuracy of 99.5% [95% CI: 98.9-99.8%] for type A and 97.5 [95% CI: 96.4-98.3%] for type B. The application did not miss any type A cases. The device flagged 32 cases incorrectly, primarily due to acquisition artefacts and aortic pathologies mimicking AD. The mean time to process and notify of potential AD cases was 27.9 ± 8.7 s. This deep learning-based application demonstrated a strong performance in detecting and classifying aortic dissection cases, potentially enabling faster triage of these urgent cases in clinical settings.

Utilizing a high‐entropy strategy, we propose a novel approach for synthesizing (Na0.4K0.1Bi0.5)TiO3 (NKBT)‐based ceramics endowed with exceptional dielectric stability at elevated temperatures. The high‐entropy effect induces a random tilt in the oxygen octahedra of NKBT ceramics, leading to a broad dielectric response characterized by diffuse phase transitions. By weakening the dielectric abnormal peak at Ts of BNT, the dielectric stability of high‐entropy NKBT ceramics is significantly enhanced. Notably, at 100 kHz, the temperature stability range of (Na0.4K0.1Bi0.5)(Ti0.65Zr0.1Sn0.15Hf0.1)O3, synthesized through the traditional solid reaction method, reaches an impressive 311°C, surpassing undoped NKBT by 257%. This significant enhancement underscores the feasibility of our high‐entropy strategy in improving dielectric performance. Our work demonstrates a straightforward and cost‐effective method for significantly improving the dielectric temperature stability of NKBT ceramics. [ABSTRACT FROM AUTHOR]

Realizing ultrahigh recoverable energy-storage density (Wrec) alongside giant efficiency (η) remains a significant challenge for the advancement of dielectrics in next-generation pulse power energy-storage (ES) devices. In this study, we introduce an entropy engineering approach, manipulating local polar fluctuations and tailoring microstructure evolution through a high-entropy design strategy, to effectively regulate the ES performance of lead-free (Bi0.5Na0.5)TiO3 (BNT)-based dielectrics. By intricately designing a high-entropy matrix, (Bi0.375Na0.3Sr0.25K0.075)TiO3 (BNSKT), and enhancing configurational entropy with the Bi(Mg0.5Sn0.5)O3 (BMS) end member, we developed multi-cation substituted BNT relaxor ceramics based on a viscous polymer process (VPP) method. Our findings reveal that modulating atomic configurational entropy yields favorable and stable microstructural characteristics, contributing to an improved breakdown electric field (E-field), reduced hysteresis and delayed polarization saturation. The VPP-synthesized high-entropy 0.85BNSKT-0.15BMS (BNT-H15VPP) ceramics achieved a significant ES density Wrec of 11.24 J cm−3, η of 88.3%, and responsivity (ξ, defined as Wrec/E) of 184 J kV−1 cm−2 under 610 kV cm−1. Additionally, pulse charging/discharging measurements indicated a large discharge energy density (Wdis) of 6.6 J cm−3, a short discharge time of 2.2 μs, and remarkable temperature stability over 20–120 °C. This work underscores the feasibility of the high-entropy strategy for designing robust dielectric ceramics, heralding promising advancements in advanced ES capacitors with comprehensive ES performance. [ABSTRACT FROM AUTHOR]

Composites with a 90%Pb(TixZr1-xO3)-10%NiFe1.98Co0.02O4 composition have been synthesized. It has been established that the polarization of samples resulting from exposure to an electric field for 1 hour of 4 kV/mm in strength at a temperature of 400 K leads to crystal structure deformation. The compression of elementary crystal cells in some areas during polarization of the sample creates conditions suitable for the enhancement of magnetic exchange interactions. It has been found that the polarization process of such compositions leads to increases in specific magnetization and magnetic susceptibility. The analysis of Mössbauer spectra has shown that the polarization of the 90%Pb(TixZr1-xO3)-10%NiFe1.98Co0.02O4 composite leads to significant changes in the effective magnetic fields of iron subspectra in various positions.

This paper studied the influence of external electric and magnetic fields on the magnetoelectric properties of layered structures of metal-piezoelectric-metal. The structures under study had the shape of a square 4 mm wide and were obtained in two steps: first, by the chemical deposition of nickel with a thickness of 0.5 μm, and then by the electrochemical deposition of nickel with a thickness of 50 μm on each side onto a lead zirconate–lead titanate substrate. Electrochemical deposition was carried out without a magnetic field on both non-polarized and polarized ceramics. Electrochemical deposition was also carried out in a magnetic field on a non-polarized and polarized PZT ceramic substrate. A magnetic field of 500 Oe at electrochemical deposition was applied in all cases in the direction of structure polarization. The maximum ME voltage coefficient 300 mV/(cmOe) was obtained at transverse orientation at bias magnetic field near 20 Oe. [ABSTRACT FROM AUTHOR]

Composites with a 90%Pb(TixZr1-xO3)-10%NiFe1.98Co0.02O4 composition have been synthesized. It has been established that the polarization of samples resulting from exposure to an electric field for 1 hour of 4 kV/mm in strength at a temperature of 400 K leads to crystal structure deformation. The compression of elementary crystal cells in some areas during polarization of the sample creates conditions suitable for the enhancement of magnetic exchange interactions. It has been found that the polarization process of such compositions leads to increases in specific magnetization and magnetic susceptibility. The analysis of Mössbauer spectra has shown that the polarization of the 90%Pb(TixZr1-xO3)-10%NiFe1.98Co0.02O4 composite leads to significant changes in the effective magnetic fields of iron subspectra in various positions. [ABSTRACT FROM AUTHOR]

Lead-free relaxor ferroelectric ceramics with outstanding energy-storage (ES) density ( W rec ) and high ES efficiency ( η ) are crucial for advanced pulse-power capacitors. This study introduces a strategic approach to maximizing the polarization difference (Δ P ) by inducing a transition from the ferroelectric phase to the ergodic relaxor (ER) phase. By employing this strategy, a series of ceramics, (1 - x )(Bi 0.5 Na 0.4 K 0.1 )TiO 3 - x (Sr 0.85 La 0.1 )(Zr 0.5 Ti 0.5 )O 3 (BNKT- x SLZT), with varying SLZT content ( x = 0.05, 0.10, 0.15, and 0.20), were designed. The addition of SLZT enhances cationic disorder, induces vacancies at A sites, and disrupts long-range ferroelectric order, facilitating the formation of polar nanoregions and enhancing relaxor ferroelectric behavior. Furthermore, a viscous polymer process (VPP) technology is employed to optimize the ceramics' structure, aiming to increase the breakdown strength ( E b ) and enhance Δ P . Ultimately, enhanced ES performance is demonstrated in BNKT-0.15SLZT VPP , achieving a remarkable W rec of 6.85 J/cm 3 and η of 84% under 470 kV/cm. This composition demonstrates excellent stability with minimal variations in W rec (3.0%) and η (4.4%) over the temperature range of 20-110 °C. Additionally, BNKT-0.15SLZT VPP exhibits exceptional pulse charge-discharge properties, featuring a high discharge density of 3.72 J/cm 3 , a large power density of 164.2 MW/cm 3 , and a short discharge time ( t 0.9 ) of 193 ns under 300 kV/cm. The study validates the practicality of BNKT-0.15SLZT VPP for pulse capacitors and underscores the potential to enhance ES performance through A-site donor doping and VPP technology. This work provides a comprehensive understanding of the interplay among composition, structure, and ES properties in lead-free relaxor dielectric ceramics, laying the groundwork for innovative advancements in the field.

Natural Killer (NK) cells are potent anti-leukemic immune effectors. However, they display multiple defects in acute myeloid leukemia (AML) patients leading to reduced anti-tumor potential. Our limited understanding of the mechanisms underlying these defects hampers the development of strategies to restore NK cell potential. Here, we have used a mouse model of AML to gain insight into these mechanisms. We found that leukemia progression resulted in NK cell maturation defects and functional alterations. Next, we assessed NK cell cytokine signaling governing their behavior. We showed that NK cells from leukemic mice exhibit constitutive IL-15/mTOR signaling and type I IFN signaling. However, these cells failed to respond to IL-15 stimulation in vitro as illustrated by reduced activation of the mTOR pathway. Moreover, our data suggest that mTOR-mediated metabolic responses were reduced in NK cells from AML-bearing mice. Noteworthy, the reduction of mTOR-mediated activation of NK cells during AML development partially rescued NK cell metabolic and functional defects. Altogether, our data strongly suggest that NK cells from leukemic mice are metabolically and functionally exhausted as a result of a chronic cytokine activation, at least partially IL-15/mTOR signaling. NK cells from AML patients also displayed reduced IL-2/15Rβ expression and showed cues of reduced metabolic response to IL-15 stimulation in vitro , suggesting that a similar mechanism might occur in AML patients. Our study pinpoints the dysregulation of cytokine stimulation pathways as a new mechanism leading to NK cell defects in AML., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bou-Tayeh, Laletin, Salem, Just-Landi, Fares, Leblanc, Balzano, Kerdiles, Bidaut, Hérault, Olive, Aurrand-Lions, Walzer, Nunès and Fauriat.)