Slot-Loaded Vivaldi Antenna for Biomedical Microwave Imaging Applications: Influence of Design Parameters on Antenna's Dimensions and Performances.

This paper demonstrates the design steps of a slot-loaded Vivaldi antenna for biomedical microwave imaging applications, showing the influence of the design parameters on the antenna's dimensions and performances. Several antenna miniaturization techniques were taken into consideration during the design: reduction in the electromagnetic wavelength by using a high-permittivity substrate material (relative permittivity ϵr=10.2), the placement of the antenna inside a coupling medium (ϵr=23), and the elongation of the current path by etching slots on each side of the radiator to reduce the antenna's lowest resonant frequency without increasing its physical dimensions.

Attenuation Tomography Using Low-frequency Ultrasound with Variational Autoencoder for Thorax Imaging: Experimental Study.

In this paper, we introduce a novel inversion methodology employing the variational autoencoder (VAE) for human thorax attenuation tomography using low-frequency ultrasound. The VAE is trained to assimilate the structural priors of the human thorax, utilizing training samples generated from computed tomography (CT) scans. This approach enables the compression of high-dimensional attenuation distributions into a lowerdimensional latent space.

Attenuation Tomography Using Low-Frequency Ultrasound for Thorax Imaging: Feasibility Study.

Low-frequency ultrasound can permeate human thorax and can be applied in functional imaging of the respiratory system. In this study, we investigate the transmission of low-frequency ultrasound through the human thorax and propose a waveform matching method to track the changes in the transmission signal during subject's respiration. The method's effectiveness is validated through experiments involving ten human subjects.

Ni(OH) Nanosheet as an Efficient Cocatalyst for Improved Photocatalytic Hydrogen Evolution over CdZnS Nanorods under Visible Light.

Loading cocatalysts to promote spatial charge separation has been confirmed as an effective method for improving photocatalytic hydrogen production. This article reports that the synthesis of Ni(OH)/CdZnS nanorod photocatalyst is suitable for photocatalytic H generation under visible light. It can be proven that the binary photocatalyst exhibits a one-dimensional nanorod morphological structure.

Three Dimensional Microwave Data Inversion in Feature Space for Stroke Imaging.

Microwave imaging is a promising method for early diagnosing and monitoring brain strokes. It is portable, non-invasive, and safe to the human body. Conventional techniques solve for unknown electrical properties represented as pixels or voxels, but often result in inadequate structural information and high computational costs.

Spatio-Temporal Classification of Lung Ventilation Patterns using 3D EIT Images: A General Approach for Individualized Lung Function Evaluation.

The Pulmonary Function Test (PFT) is a widely utilized and rigorous classification test for evaluating lung function, serving as a comprehensive diagnostic tool for lung conditions. Meanwhile, Electrical Impedance Tomography (EIT) is a rapidly advancing clinical technique that visualizes conductivity distribution induced by ventilation. EIT provides additional spatial and temporal information on lung ventilation beyond traditional PFT.

Etiological relationship between lipid metabolism and endometrial carcinoma.

Endometrial carcinoma (EC) has become one of the most common gynecological malignant neoplasms in developed countries worldwide. Studies have shown that this may be closely related to the abnormal metabolism of blood lipids, which was the most significant metabolic change in the human body in this cancer. In this review, we focus on the correlation between lipid metabolism and EC and discuss the evidence that abnormal lipid metabolism promotes an increase in EC growth and metabolism, as well as the regulatory mechanism and related signaling pathways involved in this relationship.

Risk factors for stroke in a population of central China: A cross-sectional study.

The incidence and mortality rates of stroke in China are higher than the world average, seriously endangering the public's health and quality of life. It is important to predict the incidence of stroke, identify the high-risk factors in the region, and raise the risk awareness of high-risk groups. This study sought to investigate and analyze the distribution of stroke population and the main risk factors for stroke occurrence in a Chinese population, and to predict the probability of stroke occurrence in high-risk groups with risk factors, so as to provide a scientific basis for the comprehensive prevention and treatment of stroke.

Deep feature-domain matching for cardiac-related component separation from a chest electrical impedance tomography image series: proof-of-concept study.

The cardiac-related component in chest electrical impedance tomography (EIT) measurement is of potential value to pulmonary perfusion monitoring and cardiac function measurement. In a spontaneous breathing case, cardiac-related signals experience serious interference from ventilation-related signals. Traditional cardiac-related signal-separation methods are usually based on certain features of signals.

Risk factors for the critical illness in SARS-CoV-2 infection: a multicenter retrospective cohort study.

Background: Prior studies reported that 5 ~ 32% COVID-19 patients were critically ill, a situation that poses great challenge for the management of the patients and ICU resources. We aim to identify independent risk factors to serve as prediction markers for critical illness of SARS-CoV-2 infection.

Methods: Fifty-two critical and 200 non-critical SARS-CoV-2 nucleic acid positive patients hospitalized in 15 hospitals outside Wuhan from January 19 to March 6, 2020 were enrolled in this study.

Supervised Descent Learning for Thoracic Electrical Impedance Tomography.

Objective: The absolute image reconstruction problem of electrical impedance tomography (EIT) is ill-posed. Traditional methods usually solve a nonlinear least squares problem with some kind of regularization. These methods suffer from low accuracy, poor anti-noise performance, and long computation time.

Long non‑coding RNA NEAT1 modifies cell proliferation, colony formation, apoptosis, migration and invasion via the miR‑4500/BZW1 axis in ovarian cancer.

Ovarian cancer (OC) is a frequently occurring malignant tumor in women. Increasing evidence has indicated that long non‑coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) participates in OC pathogenesis. Thus, the aim of the present study was to explore the function of NEAT1 during OC progression.

Ag-Modified g-CN Prepared by a One-Step Calcination Method for Enhanced Catalytic Efficiency and Stability.

Ag-decorated g-CN (denoted as Ag/CN-) was prepared by a one-step calcination method, and the influences of calcination time on structure, morphology, surface composition, photocatalytic performance, and catalytic reduction activity of the prepared Ag/CN- samples were investigated. The tests showed that the Ag/CN-8 prepared through by calcination for 8 h exhibited the best photocatalytic degradation efficiency of methyl orange (98.7% within 2 h) and the best catalytic reduction property of 4-nitrophenol (100% within 70 s).

Neural network-based supervised descent method for 2D electrical impedance tomography.

Objective: In this work, we study the application of the neural network-based supervised descent method (NN-SDM) for 2D electrical impedance tomography.

Approach: The NN-SDM contains two stages: offline training and online prediction. In the offline stage, neural networks are iteratively applied to learn a sequence of descent directions for minimizing the objective function, where the training data set is generated in advance according to prior information or historical data.

Study on 3-D Acoustic Imaging for Human Thorax Based on Contrast Source Inversion.

In this article, we study a 3-D acoustic imaging algorithm that can reconstruct compressibility, attenuation, and density simultaneously based on the contrast source inversion (CSI) method. This is a nonlinear and ill-posed inverse problem. To deal with the nonlinearity, we introduce two asymmetrical contrast sources that are functions of the contrasts and the total field.

Three-Dimensional Electrical Impedance Tomography With Multiplicative Regularization.

Objective: The multiplicative regularization scheme is applied to three-dimensional electrical impedance tomography (EIT) image reconstruction problem to alleviate its ill-posedness.

Methods: A cost functional is constructed by multiplying the data misfit functional with the regularization functional. The regularization functional is based on a weighted L-norm with the edge-preserving characteristic.

Feasibility study of acoustic imaging for human thorax using an acoustic contrast source inversion algorithm.

In this work, an acoustic imaging method based on contrast source inversion and its feasibility in quantitatively reconstructing compressibility, attenuation, and density of human thorax is studied. In the acoustic wave equation, the inhomogeneity in density makes the relationship between the contrasts and the total pressure highly nonlinear. To reduce this nonlinearity, two contrast sources are introduced to ensure symmetry in the equation, such that the inverse problem can be solved efficiently by alternately updating two contrast sources and two contrasts.

A Passive Temperature-Sensing Antenna Based on a Bimetal Strip Coil.

A passive temperature-sensing antenna is presented in this paper, which consists of a meandering dipole, a bimetal strip and a back cavity. The meandering dipole is divided into two parts: the lower feeding part and the upper radiating part, which maintain electric contact during operation. As a sensing component, a bimetal strip coil offers a twisting force to rotate the lower feeding part of the antenna when the temperature varies.

A programmable metasurface with dynamic polarization, scattering and focusing control.

Diverse electromagnetic (EM) responses of a programmable metasurface with a relatively large scale have been investigated, where multiple functionalities are obtained on the same surface. The unit cell in the metasurface is integrated with one PIN diode, and thus a binary coded phase is realized for a single polarization. Exploiting this anisotropic characteristic, reconfigurable polarization conversion is presented first.

Genetic ablation of Smoothened in pancreatic fibroblasts increases acinar-ductal metaplasia.

The contribution of the microenvironment to pancreatic acinar-to-ductal metaplasia (ADM), a preneoplastic transition in oncogenic Kras-driven pancreatic cancer progression, is currently unclear. Here we show that disruption of paracrine Hedgehog signaling via genetic ablation of Smoothened (Smo) in stromal fibroblasts in a Kras(G12D) mouse model increased ADM. Smo-deleted fibroblasts had higher expression of transforming growth factor-α (Tgfa) mRNA and secreted higher levels of TGFα, leading to activation of EGFR signaling in acinar cells and increased ADM.

Cognitive impairment and gray matter volume abnormalities in silent cerebral infarction.

To investigate the association between cognitive impairment and gray matter volume (GMV) abnormalities in silent cerebral infarction (SCI) patients, the GMV of 62 pairs of patients and well-matched healthy controls was calculated. All participants underwent a P300 test, a Montreal Cognitive Assessment (MoCA) test. Compared with controls, the patients showed decreased GMV in the left superior frontal gyrus, left inferior frontal gyrus, left superior temporal gyrus, right middle temporal gyrus, and bilateral parahippocampal gyrus; no significantly increasing GMV was found.