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We propose a parallel negative-capacitance field-effect transistor (P-NCFET) structure, in which a ferroelectric operating in its negative-capacitance region is placed in parallel with the gate and source terminals of a MOSFET. The P-NCFET is stabilized by combining careful matching of the ferroelectric with the gate capacitance along with simple feedback realized using current mirrors. The novel stabilization approach opens the possibility for a variety of new applications that exploit the negative capacitance of ferroelectrics to cancel capacitance in integrated circuits. As an example, we show the P-NCFET structure has a significantly higher unity-current-gain frequency ${f}_{T}$ compared to a conventional MOSFET. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of mitochondrial damage-associated molecular patterns on the lung fluid homeostasis in experimental acute lung injury.Design: Experimental study.Setting: Research laboratory.Subjects: Patients with acute respiratory distress syndrome and control subjects, wild-type C57BL/6 and formyl peptide receptor-1 gene knockout mice, and primary rat alveolar epithelial type II cells.Interventions: Samples of bronchoalveolar lavage fluid and serum were obtained from patients and control subjects. Mice were intratracheally instilled with lipopolysaccharide and mitochondrial damage-associated molecular patterns. The primary rat alveolar epithelial type II cells were isolated and incubated with mitochondrial damage-associated molecular patterns.Measurements and Main Results: Patients were divided into direct (pulmonary) and indirect (extrapulmonary) injury groups based on etiology. The release of mitochondrial peptide nicotinamide adenine dinucleotide dehydrogenase 1 in both bronchoalveolar lavage fluid and serum was induced in patients and was associated with etiology. In the lipopolysaccharide-induced lung injury, administration of mitochondrial damage-associated molecular patterns exacerbated the lung fluid imbalance, which was mitigated in formyl peptide receptor-1 knockout mice. Proteomic analysis of mouse lung tissues revealed the involvement of ion channels and tight junction proteins in this process. Treatment with mitochondrial damage-associated molecular patterns decreased the expression of epithelial sodium channel α, zonula occludens-1, and occludin via the formyl peptide receptor-1/p38 pathway in the primary rat alveolar epithelial type II cells.Conclusions: Mitochondrial damage-associated molecular patterns exacerbate lung fluid imbalance in the experimental acute lung injury model through formyl peptide receptor-1 signaling, the inhibition of which may prevent exacerbation of lung fluid imbalance induced by mitochondrial damage-associated molecular patterns. Thus, formyl peptide receptor-1 is a potential therapeutic target for acute respiratory distress syndrome. [ABSTRACT FROM AUTHOR]

Ferroelectric and negative-capacitance field-effect transistors (FeFETs and NCFETs) have recently garnered great attention as devices for applications in memory and low-power logic, respectively. As these technologies are pursued, it is critical to have a variety of measurement approaches, including methods familiar to the electron-device and microwave communities that can aid in fully understanding the behavior of ferroelectrics in FeFETs and NCFETs. In this paper, we propose and show the viability of using frequency-domain electrical measurement techniques employing the well-known microwave S-parameters, and their large-signal generalization and X-parameters. Our methods provide the means to trace the intrinsic polarization versus electric-field curve of the ferroelectric, i.e., with the parasitics de-embedded, thereby showing the innate ferroelectric response, which cannot be done using conventional techniques. These methods also enable extraction of all the parameters of the Landau–Khalatnikov equation, which is commonly used to model ferroelectric behavior in FeFETs and NCFETs. This paper hence takes a useful step toward methods familiar to the electron-device community that can help to better understand and optimize FeFET and NCFET technologies. [ABSTRACT FROM AUTHOR]

Recently, negative-capacitance FETs (NCFETs) have been proposed to reduce subthreshold slope and help continue supply-voltage scaling alongside channel-length scaling. We investigate the high-frequency switching behavior of NCFETs using the Landau–Khalatnikov equation to model ferroelectric materials. Multidomain interactions in the ferroelectric are considered, resulting in strong agreement with experimental measurements. Operation of NCFETs at gigahertz frequencies is investigated with this experimentally validated multidomain model. We find that the effectiveness of the voltage amplification in NCFETs is strongly dependent on the viscosity coefficient $\rho $ of the ferroelectric, and that a low \rho $ ( <0.1~\Omega \cdot \text {m} ) is required for the operation at the high gigahertz frequencies. [ABSTRACT FROM PUBLISHER]

The potential for negative-capacitance field-effect transistors (NCFETs) to enhance the unity-current-gain cutoff frequency ${f}_{T}$ and ${g}_{m}{f}_{T}/{I}_{D}$ ratio through a technique that mitigates the impacts of extrinsic parasitic capacitances is investigated, where ${g}_{m}$ is the transconductance and ${I}_{D}$ is the dc drain current and where “extrinsic” refers to elements arising outside an “intrinsic” or core transistor structure. We explain the technique and show that NCFETs can provide significant gains in extrinsic ${f}_{T}$ and ${g}_{m}{f}_{T}/{I}_{D}$ from this mitigation effect. However, an inherent degradation of intrinsic ${f}_{T}$ needs to be addressed to maximize these benefits, and this degradation can be alleviated through channel-length scaling as well as supply- and threshold-voltage tuning. The relative influences of different extrinsic parasitic elements are also evaluated, and it is found that improvements to ${f}_{T}$ and ${g}_{m}{f}_{T}/{I}_{D}$ increase as extrinsic parasitic capacitance increases and decrease as extrinsic parasitic resistance increases. Overall, this work finds that NCFET structures are promising candidates to mitigate the impacts of extrinsic parasitics in aggressively scaled transistors for the next-generation RF applications. [ABSTRACT FROM AUTHOR]

As continuous development and optimization of negative-capacitance field-effect transistors (NCFETs) are pursued for digital applications, it is also desirable to examine the radio frequency (RF) performance of these devices, especially devices with the metal–ferroelectric–insulator–semiconductor (MFIS) structure. In this article, we use a combination of physics-based modeling and small-signal circuits to investigate the RF performance of MFIS NCFETs using three key device figures of merit: the well-known unity-current-gain (cutoff) frequency ƒT and the well-known maximum oscillation frequency ƒmax, and another important metric specified by gmƒT/ID , where gm is the transconductance and ID is the dc drain current. We find that MFIS NCFETs achieve similar ƒTand ƒmax performance to conventional MOSFETs, but offer a significant advantage in gmƒT/ ID. [ABSTRACT FROM AUTHOR]

We examine the impact of line-edge roughness (LER) on the variability in the on-current and saturation threshold voltage of ultrascaled FinFET devices via quantum-mechanical transport simulation. We obtain a realistic model of LER by decomposing the LER into short- $\lambda $ and long- $\lambda $ fluctuations, and we consider their separate influences on device performance. We show that the long- $\lambda $ fluctuations lead to greater device variability than the short- $\lambda $ fluctuations, and we explain the difference between the two cases via the influence of fluctuating quantum confinement arising from the LER. Finally, we consider devices in which the long- $\lambda $ fluctuations of the two fin edges are correlated and demonstrate that this correlation significantly improves the variability. Thus, we show the continued need for fabrication technology either to reduce the amplitude of the long- $\lambda $ fluctuations or to ensure the long- $\lambda $ fluctuations between the sidewalls of ultrascaled FinFET devices are correlated. [ABSTRACT FROM AUTHOR]

Objective In cerebral aneurysm clipping and embolization, blood pressure control and temporary parent artery blocking are common methods to prevent aneurysm rupture. Their influence on the prognosis is uncertain. In this study, we try to find out the association between methods above and prognostic indicators. Methods We held a retrospective analysis on patients' medical records of cerebral aneurysms surgical clipping and endovascular coiling, and recorded gender, age, diagnosis, Hunt-Hess grade, Glasgow coma scale score, treatment methods, a history of hypertension, preoperative systolic blood pressure, with or without controlled hypotension, systolic blood pressure difference before and after controlled hypotension, with or without temporary artery blocking, with or without hypertension after treated aneurysm, prognostic indicators including mortality after 1 month, intensive care unit (ICU) stay time of survivors, discharged Glasgow outcome scale (GOS) score. Prognostic indicators were regarded as dependent variable, all the factors were regarded as independent variable, and the strength analysis of influence factors on prognostic indicators was made by binary logistic regression. Results Total cases were 165, including 68 males and 97 females, with an average age of 56 (12–85) years. The mortality after 1 month was 10.9% (18 cases). The ICU stay time of survivors was 7.35 (0–67) days. GOS score at discharge was 1–3 in 40 (24.2%) patients and 4–5 in 125 (75.8%) patients. Systolic blood pressure difference before and after controlled hypotension was an independent factor influencing mortality ( t =2.273, P =0.024), and the greater the difference was, the higher the mortality would be. Timely hypertension after aneurysm treated was an independent factor affecting ICU stay time of survivors and patients with hypertension had shorter ICU stay time (χ 2 =10.017, P =0.001). Blood pressure control (χ 2 =0.088, P =0.767) and temporary blocking (χ 2 =1.307, P =0.253) did not show significant influence on GOS score at discharge. Conclusions Timely controlled hypertension after aneurysm clipping and embolization can significantly shorten the stay time in ICU. The degree of controlled hypotension associates with postoperative mortality, the greater systolic blood pressure difference before and after antihypertensive treatment is, the higher the mortality will be. [ABSTRACT FROM AUTHOR]