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Phase unwrapping of high phase noise and steep phase gradient has always been a challenging problem in interferometric synthetic aperture radar (InSAR), in which case the least squares (LS) phase unwrapping method often suffers from significant unwrapping errors. Therefore, this paper proposes an improved LS phase unwrapping method based on the Chebyshev filter, which solves the problem of incomplete unwrapping and errors under high phase noise and steep phase gradient. Firstly, the steep gradient phase is transformed into multiple flat gradient phases using the Chebyshev filter. Then the flat gradient phases are unwrapped using the LS unwrapping method. Finally, the final unwrapped phase is obtained by iteratively adding the unwrapping results of the flat gradient phases. The simulation results show that the proposed method has the best accuracy and stability compared to LS, PCUA, and RPUA. In the real InSAR phase unwrapping experiment, the RMSE of the proposed method is reduced by 63.91%, 35.38%, and 54.39% compared to LS, PCUA, and RPUA. The phase unwrapping time is reduced by 62.86% and 11.64% compared to PCUA and RPUA. [ABSTRACT FROM AUTHOR]

Highly permeable targeted chemotherapy is highly desired for treating non-small cell lung cancer (NSCLC). In this study, a novel stimulus-responsive, carrier-free, and triple-combination nano-system (identified as UA@CA4-SS-Cer nanoparticles [NPs]) is developed for the systemic treatment of ALK/EGFR dual-mutant NSCLC. This nanomedicine addresses concerns related to low drug loading and inefficient drug permeability and it provides the foundation for developing GSH-sensitive nanoparticles for improved drug delivery. [ABSTRACT FROM AUTHOR]

The phase gradient autofocus (PGA) and its improvements have been aimed to estimate the phase error exclusively from the phase of raw data. In this article, we introduced the Kalman filter (KF) into stripmap PGA (or phase curvature autofocus) by taking advantage of the continuous movement of the aircraft. The fundamental principle is to build a kinematic model and a measurement model to predict the phase curvature of the next subaperture, and to correct the measurement (phase curvature) of the current subaperture. The advantages of employing KF are as follows: 1) the inaccurate PGA estimation due to wrong target selection, serious phase error, or low signal-to-clutter ratio can be corrected by a well-maintained KF; 2) the prediction of the KF can be applied to the data of the next subaperture before phase estimation, to decrease the algorithm converge time, and to increase the estimation accuracy; and 3) KF disciplined PGA naturally fits the sequential processing needs and is capable of generating good phase error estimation in one execution. This helps real-time synthetic aperture radar (SAR) autofocus and motion compensation. The disciplining of the autofocus using KF is not restricted to PGA-based algorithm. It can be applied to other subaperture-based autofocus algorithms. [ABSTRACT FROM AUTHOR]

Phages are highly abundant in the human gut, yet most of them remain uncultured. Here, we present a gut phage isolate collection (GPIC) containing 209 phages for 42 commensal human gut bacterial species. Genome analysis of the phages identified 34 undescribed genera. We discovered 22 phages from the Salasmaviridae family that have small genomes (∼10–20 kbp) and infect Gram-positive bacteria. Two phages from a candidate family, Paboviridae , with high prevalence in the human gut were also identified. Infection assays showed that Bacteroides and Parabacteroides phages are specific to a bacterial species, and strains of the same species also exhibit substantial variations in phage susceptibility. A cocktail of 8 phages with a broad host range for Bacteroides fragilis strains effectively reduced their abundance in complex host-derived communities in vitro. Our study expands the diversity of cultured human gut bacterial phages and provides a valuable resource for human microbiome engineering. [Display omitted] • Large-scale cultivation was used to isolate 209 phages for 42 human gut bacterial species • Genomic analysis reveals isolated phage diversity and discovers two phage families • Bacteroides and Parabacteroides strains show great variations in phage susceptibility • A phage cocktail reduces abundance of the targeted species in communities in vitro Shen et al. isolate and characterize a collection of 209 phages for human gut bacteria. They discover Salasmaviridae phages with small genomes and highly prevalent candidate Paboviridae phages. A phage cocktail reduced abundance of the targeted species in host-derived communities in vitro , suggesting their application in targeting the gut microbiome. [ABSTRACT FROM AUTHOR]

Phase Gradient Autofocus (PGA) is an algorithm developed to estimate phase errors in synthetic aperture radar (SAR) images. It is widely used in SAR image processing and has been shown to be very robust on a variety of imagery and phase error functions. Original PGA makes a narrow beam assumption, which is valid for most SAR systems. But it is known that the narrow beam assumption is not valid for large swath or low-altitude mode SAR, where range-dependent phase errors need to be compensated. Some PGA-based range-dependent autofocus algorithms were proposed to deal with this problem, but during raw data processing, we found that there are ill-posed problems in the linear motion error estimation model that will affect the accuracy of the estimation. In this article, combining the Tikhonov regularization (TR) method with phase gradient estimation, a novel autofocus algorithm is proposed to deal with the ill-posed problem in estimation. Real data processing demonstrates that the new method avoids the effect of parameter errors, estimates the range-dependent phase errors more precisely and finally leads to better focusing quality. [ABSTRACT FROM AUTHOR]

The frequency modulated continuous‐wave (FMCW) technique has been used in many radar applications owing to its low requirements on radar hardware. Linear sawtooth sweep (the frequency sweeps in one direction) is one of the simplest waveforms employed by most FMCW radars. By theory and real data it is proved that by simply using the linear triangular sweep (the frequency goes first down and then up), the range resolution can be doubled without increasing the transmitted bandwidth. [ABSTRACT FROM AUTHOR]

Background: Autophagy is an essential cellular process involving the self-degradation and recycling of organelles, proteins, and cellular debris. Recent research has shown that autophagy plays a significant role in the occurrence and development of kidney diseases. However, there is a lack of bibliometric analysis regarding the relationship between autophagy and kidney diseases. Methods: A bibliometric analysis was conducted by searching for literature related to autophagy and kidney diseases in the Web of Science Core Collection (WoSCC) database from 2000 to 2022. Data processing was carried out using R package "Bibliometrix", VOSviewers, and CiteSpace. Results: A total of 4,579 articles related to autophagy and kidney diseases were collected from various countries. China and the United States were the main countries contributing to the publications. The number of publications in this field showed a year-on-year increasing trend, with open-access journals playing a major role in driving the literature output. Nanjing Medical University in China, Osaka University in Japan, and the University of Pittsburgh in the United States were the main research institutions. The journal "International journal of molecular sciences" had the highest number of publications, while "Autophagy" was the most influential journal in the field. These articles were authored by 18,583 individuals, with Dong, Zheng; Koya, Daisuke; and Kume, Shinji being the most prolific authors, and Dong, Zheng being the most frequently co-cited author. Research on autophagy mainly focused on diabetic kidney diseases, acute kidney injury, and chronic kidney disease. "Autophagy", "apoptosis", and "oxidative stress" were the primary research hotspots. Topics such as "diabetic kidney diseases", "sepsis", "ferroptosis", "nrf2", "hypertension" and "pi3k" may represent potential future development trends. Research on autophagy has gradually focused on metabolic-related kidney diseases such as diabetic nephropathy and hypertension. Additionally, PI3K, NRF2, and ferroptosis have been recent research directions in the field of autophagy mechanisms. Conclusion: This is the first comprehensive bibliometric study summarizing the relationship between autophagy and kidney diseases. The findings aid in identifying recent research frontiers and hot topics, providing valuable references for scholars investigating the role of autophagy in kidney diseases., 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 © 2023 Ai, Li, Zheng, Wang, Liu, Tao, Li and Wang.)

Frequency modulated continuous wave (FMCW) technique has recently been employed by synthetic aperture radar (SAR) to decrease the radar cost and volume. However, the operation range is limited by the direct energy leakage from the transmitting channel to receiving channel due to the operation principle of FMCW technique. Bistatic configuration is an efficient way to increase the isolation between the transmitter and receiver, which could significantly increase the radar standoff range. A bistatic FMCW SAR spectrum model is proposed by using the Fresnel approximation in this paper. This model is similar to that of a monostatic FMCW SAR spectrum, which allows the existing imaging algorithms to be used on bistatic image processing. Based on the new model and the characteristics of FMCW signal, a modified range migration algorithm (RMA) for FMCW SAR is proposed to focus the image, which requires less memory and computational load than the traditional RMA. Point-target simulation is used to verify the proposed spectral model and real data processing verified the effectiveness of the proposed RMA.