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Ship motions during long coherent processing interval (CPI) have six degrees of freedom, and the oscillatory motions are roughly periodical. The traditional ship imaging methods usually use a short time interval to form an image, while the image quality may suffer from low resolution, poor signal-to-noise ratio (SNR), and scatter scintillation. Using a longer CPI to generate an image may improve the quality but, however, largely increase the focusing difficulty. In this article, we investigate the focusing challenges of oscillatory ships with long CPI. Through analyzing the relative motion between the radar and the ship, the properties of wavenumber domain support (WDS) and point spreading function (PSF) of oscillatory ship imaging are studied. It is illustrated that the WDS is a 3-D sparse curved surface generated by the complex relative motion, with a time-variant energy density, nonparallel spectrum boundaries, and a complex structure. The PSF of an oscillatory ship may have a 3-D resolution but also multiple high-level sidelobes. The relationship between the WDS and the nonideal PSF is illustrated with the projection slice theorem (PST). Moreover, it is discussed that the scatterers distributed on a 3-D ship cannot be focused uniformly on a 2-D imaging plane (IP) due to the variation of the slant-range plane (SRP). The projection relationships of the resolutions and focusing positions between the SRP and the IP are also derived. Simulation results are presented to validate the analyses throughout this article.

Objective. To study the expression and correlation of insulin receptor (INSR), insulin receptor substrate-1 (IRS-1), and programmed cell death ligand-1 (PD-L1) in nonsmall cell lung cancer (NSCLC). Methods. 45 lung cancer tissues and 30 adjacent normal tissues of NSCLC patients diagnosed in the Second Affiliated Hospital of Shandong First Medical University from June 2019 to August 2020 were selected. The expressions of INSR, IRS-1, and PD-L1 proteins in tumor tissues and adjacent tissues of NSCLC were detected by immunohistochemical staining. Results. The expression of INSR and IRS-1 in NSCLC was significantly higher than that in adjacent normal lung tissue ( P < 0.05 ). INSR expression had statistical significance with the degree of pathological differentiation of nonsmall cell carcinoma ( P = 0.031 ), but had no significant association with age, gender, pathological type, TNM stage, and lymph node metastasis status ( P > 0.05 ). There was no significant correlation between IRS-1 positive expression and NSCLC patients’ age, gender, pathological typing, degree of differentiation, TNM stage, and lymph node metastasis ( P > 0.05 ). PD-L1 positive expression was correlated with lymph node metastasis of NSCLC ( P = 0.028 ), while there was no significant correlation with gender, age, pathological type, TNM stage, and pathological differentiation degree of NSCLC patients ( P > 0.05 ). Spearman correlation analysis showed that PD-L1 protein expression had a significant positive correlation with IRS-1 protein expression ( r = 0.373 ), but was not correlated with the expression of INSR protein. Conclusion. IRS-1 may be involved in the regulation of PD-L1 expression and mediate the occurrence of tumor immune escape, which is expected to become a new target for NSCLC immunotherapy and provide new clinical evidence for immunosuppressive therapy.

To explore the mechanisms whereby dexmedetomidine reversed lung injury in rats with toxic shock via inhibiting inflammation and autophagy.Thirty-six specific pathogen-free male Sprague Dawley rats with were screened and randomly divided into three groups. Toxic shock was induced by intestinal leakage. The control group received no cecal ligation and the treatment group received dexmedetomidine hydrochloride. Lung tissue morphology was studied by hematoxylin-eosin staining. The expression levels of inflammatory cytokines including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were determined by Reverse Transcription-Polymerase Chain Reaction (RT-PCR). The expression levels of beclin l and LC3 were measured, and the expression levels of apoptosis gene Bax and Bcl-2 were determined. The autophagosomes in lung cells were observed by transmission electron microscopy. Extracellular signal-regulated kinase (ERK) 1/2 expression was determined by Western blotting assays.The results showed that the W/D, total protein and myeloperoxidase (MPO) index in the toxic shock group were 5.45 ± 0.35, 3.21 ± 0.47 and 4.53 ± 0.36, respectively. The W/D (4.02 ± 0.67), total protein (2.01 ± 0.35) and MPO index (2.31 ± 0.59) were significantly lower in the dexmedetomidine group (p0.05). Similarly, compared with the toxic shock group, the expression of p-ERK1/2 protein in the dexmedetomidine treatment group was significantly decreased (p0.05). The expression levels of autophagy proteins beclin1 and LC3 in the dexmedetomidine treatment group were not significantly different from those of the control group (p0.05). Transmission electron microscopy showed that the number of autophagic bodies in lung cells decreased. After induction with dexmedetomidine hydrochloride, the proapoptotic gene Bax was significantly downregulated in the cells. Bax expression levels in each group were 0.36 ± 0.12, 0.67 ± 0.06, and 0.32 ± 0.12, respectively. Compared with the control group, Bax expression in lung tissue significantly increased in the toxic shock group (p0.05).Dexmedetomidine attenuates lung injury in toxic shock rats by inhibiting inflammation and autophagy.

The microwave photonic (MWP) radar technique is capable of providing ultrawide frequency bandwidth waveforms to generate ultrahigh-resolution (UHR) inverse synthetic aperture radar (ISAR) imagery. Nevertheless, conventional ISAR imaging algorithms have limitations in focusing UHR MWP-ISAR imagery, where high-precision high-order range cell migration (RCM) and phase correction are crucially necessary. In this article, a UHR MWP-ISAR imaging algorithm integrating rotation estimation and high-order motion terms compensation is proposed. By establishing the relationship between parametric ISAR rotation model and high-order motion terms, an average range profile sharpness maximization (ARPSM) is developed to obtain rotation velocity by using nonuniform fast Fourier transform (NUFFT). Second-order range-dependent RCM is corrected with parametric compensation model by using the rotation velocity estimation. Furthermore, the spatial-variant high-order phase error is extracted to compensation by the entire image sharpness maximization (EISM). A new imaging framework is established with two one-dimensional (1-D) parameter estimations: ARPSM and EISM. Extensive experiments demonstrate that the proposed algorithm outperforms traditional ISAR imaging strategies in high-order RCM correction and azimuth focusing performance.

Global navigation satellite system (GNSS) and interferometric synthetic aperture radar (InSAR) data are integrated to extract the 3-D surface deformations, which are of great significance for studying geological hazards. In this study, two major problems are focused on integration. For one thing, we propose an iterated almost unbiased estimation (IAUE) method to estimate the variance components of GNSS and InSAR for the case where the estimation of variance components of multisource data by traditional variance component estimation methods may be negative and inaccurate. For another, considering that heterogeneous data errors may lead to unstable 3-D solutions, we propose adding the Laplacian smoothness constraint (LSC) to the function model, which can smooth the solutions by minimizing the second derivative of the displacements. These two methods are abbreviated as IAUE-LSC. In the simulation experiment, the performance of traditional Helmert variance component estimation is first compared with IAUE. IAUE can not only converge more quickly, but also avoid negative variances. Furthermore, we find that the excessively large relative error ratio between GNSS and InSAR is an essential factor leading to the instability of the 3-D solutions. The IAUE-LSC method is immune to this instability and can obtain more stable results. In addition, the 2018 Hawaii case demonstrates that IAUE achieves improvements of 2.58, 2.77, and 7.69 cm in the east, north, and up directions relative to the traditional weighted least-squares method, while the combined IAUE-LSC achieves improvements of 2.29, 0.32, and 1.68 cm compared to the IAUE alone.

The water body detection in high-resolution synthetic aperture radar (SAR) images is a challenging task due to the changing interference caused by multiple imaging conditions and complex land backgrounds. Inspired by the excellent adaptability of deep neural networks (DNNs) and the structured modeling capabilities of probabilistic graphical models, the cascaded fully-convolutional network (CFCN) is proposed to improve the performance of water body detection in high-resolution SAR images. First, for the resolution loss caused by convolutions with large stride in traditional convolutional neural network (CNN), the fully-convolutional upsampling pyramid networks (UPNs) are proposed to suppress this loss and realize pixel-wise water body detection. Then considering blurred water boundary, the fully-convolutional conditional random fields (FC-CRFs) are introduced to UPNs, which reduce computational complexity and lead to the automatic learning of Gaussian kernels in CRFs and the higher boundary accuracy. Furthermore, to eliminate the inefficient training caused by imbalanced categorical distribution in the training data set, a novel variable focal loss (VFL) function is proposed, which replaces the constant weighting factor of focal loss with the frequency-dependent factor. The proposed methods can not only improve the pixel accuracy and boundary accuracy but also perform well in detection robustness and speed. Results of GaoFen-3 SAR images are presented to validate the proposed approaches.

The rotation matching between synthetic aperture radar (SAR) and optical images is essential for their registration. In this article, we introduce a novel fast rotation matching method for SAR and optical images. In the method, the absolute directional derivative histograms (ADDHs) of SAR and optical images can be used to reflect the rotation difference between them, and then the rotation difference is removed by the cross correlation of the two images’ ADDHs. Subsequently, we generate the ADDHs by oriented Gaussian-Gamma-shaped operator. Then, the cross correlation based on fast Fourier transform is used to deal with the ADDHs of SAR and optical images in order to determine the rotation difference of the two images. The experiment results demonstrate that the proposed method can detect the rotation difference in various conditions and achieves rotation matching with high speed.

Background Nodular fasciitis (NF) is a benign disease originating from fascial tissue and most commonly occurs in the extremities, followed by the trunk, head, and neck. NF of the head and neck occurs mainly in the face and neck, and it has not been reported in the occipital region. Case summary A 30-year-old man was admitted because of a mass in the left occipital region. Imaging examination revealed a soft tissue nodule in the left occipital area. An enhanced magnetic resonance imaging scan showed characteristic inverted target and fascial tail signs. Histopathological analysis showed a large amount of spindle cell proliferation, and immunohistochemistry showed positive expression of SMA in the spindle cells in the lesion. Finally, nodular fasciitis was diagnosed. Conclusion NF of the head and neck is rare, but the possibility of NF should be considered when nodules or masses with rapid subcutaneous growth are found and tenderness in the head and neck is present. Imaging examination, in combination with clinical manifestations and histopathological examination, can improve the diagnostic accuracy for the disease. After diagnosis, local surgical resection is the first choice of treatment.

Background Endometrial stromal sarcoma (ESS) is a rare malignant mesenchymal tumor. Early in the disease, the findings on magnetic resonance imaging are similar to those of leiomyoma. When the lesion involves both vascular and cardiac tissue, it might be misdiagnosed as intravenous leiomyomatosis, which is not common in the clinic. Case summary We present the case of a 34-year-old female patient with tumor embolus, which extended from the right iliac vein and ovarian vein to the inferior vena cava (IVC), and then to the right atrium and right ventricle, and finally protruded into the pulmonary artery. The patient had undergone a hystero-myomectomy 7 years previously. Based on the findings of the imaging examinations, the diagnosis of intravenous leiomyomatosis was considered preoperatively. The patient then underwent complete resection of the endovascular and intracardiac tumor embolus. The postoperative pathology results confirmed metastatic ESS with endovascular and intracardiac involvement. The patient was discharged from hospital in good condition, and there was no sign of recurrence 5 mo after the operation. Conclusion Extending from the iliac vein and ovarian vein to the IVC, this metastatic ESS invaded both vascular and cardiac tissues. For patients with ESS involving vascular and cardiac tissues, pathological examinations are essential for the differential diagnosis, such as intravenous leiomyomatosis. In addition, due to the high recurrence rate of ESS, long-term and close follow-up evaluation is necessary.

The beam steering of high-squint terrain observation by progressive scans (TOPS) synthetic aperture radar (SAR) mounted on maneuvering platforms causes azimuth spectrum aliasing and nonlinear variation of the Doppler center with target azimuth position. A joint time-Doppler deramp (JTDD) based method is proposed and mainly contains two parts. First, for the azimuth spectrum aliasing, the unfolded 2-D spectrum is obtained by a modified linear deramp function in the azimuth time domain constructed from the 3-D motion parameters. After range cell migration correction (RCMC), the data supporting area in the azimuth time domain is expanded, and thus, aliased because of the nonlinear variation of Doppler center. Then, a nonlinear deramp operation in the Doppler domain is further proposed to obtain a nonaliasing signal. The proposed algorithm is efficient with less zero-padding due to the consideration of nonlinear components of Doppler center variation. Simulation and real SAR data processing are presented to validate the proposed algorithm.

The rigid oscillation and flexible deformation baseline errors occur in dual-antenna unmanned aerial vehicle (UAV) SAR interferometry (InSAR). The errors caused by airflow disturbances and UAV platform mechanical oscillation will lead to interferometric phase undulation. Measuring the errors has high requirements for length and time accuracy for the equipment. In this paper, a time-varying baseline error (TBE) estimation and compensation method based on continuous time-domain subaperture data is proposed. Firstly, we model the TBE and derive its expression in each subaperture image focused by the chirp scaling dechirp (CS-dechirp) algorithm. Then it is possible to extract the estimated differential TBE (D-TBE) from the differential interferogram of overlapping scenes in subaperture images. Further, the full-aperture TBE can be obtained through an integration of the estimated D-TBE. Finally, the full-aperture compensation can be accomplished by a phase correction after the range variation estimation. Taking advantage of the time-domain subaperture, the D-TBE phases are sampled at each subaperture center time, and the proposed method can be well combined with a motion compensation algorithm in the processing flow for UAV InSAR. Furthermore, the case of low coherence is overcome. The results of simulation and real measured airborne single-pass dual-antenna data validate the proposed approach.

Although SWI/SNF chromatin remodelling complexes are known to regulate diverse biological functions in plants, the classification, compositions and functional mechanisms of the complexes remain to be determined. Here we comprehensively characterized SWI/SNF complexes by affinity purification and mass spectrometry in Arabidopsis thaliana, and found three classes of SWI/SNF complexes, which we termed BAS, SAS and MAS (BRM-, SYD- and MINU1/2-associated SWI/SNF complexes). By investigating multiple developmental phenotypes of SWI/SNF mutants, we found that three classes of SWI/SNF complexes have both overlapping and specific functions in regulating development. To investigate how the three classes of SWI/SNF complexes differentially regulate development, we mapped different SWI/SNF components on chromatin at the whole-genome level and determined their effects on chromatin accessibility. While all three classes of SWI/SNF complexes regulate chromatin accessibility at proximal promoter regions, SAS is a major SWI/SNF complex that is responsible for mediating chromatin accessibility at distal promoter regions and intergenic regions. Histone modifications are related to both the association of SWI/SNF complexes with chromatin and the SWI/SNF-dependent chromatin accessibility. Three classes of SWI/SNF-dependent accessibility may enable different sets of transcription factors to access chromatin. These findings lay a foundation for further investigation of the function of three classes of SWI/SNF complexes in plants.

Yeasts represent a group of the microorganisms most frequently seen in biotechnology. Recently, the class 2 type II CRISPR system (CRISPR/Cas9) has become the principal toolbox for genome editing. By efficiently implementing genetic manipulations such as gene integration/knockout, base editor, and transcription regulation, the development of biotechnological applications in yeasts has been extensively promoted. The genome-level tools based on CRISPR/Cas9, used for screening and identifying functional genes/gene clusters, are also advancing. In general, CRISPR/Cas9-assisted editing tools have gradually become standardized and function as host-orthogonal genetic systems, which results in time-saving for strain engineering and biotechnological application processes. In this review, we summarize the key points of the basic elements in the CRISPR/Cas9 system, including Cas9 variants, guide RNA, donors, and effectors. With a focus on yeast, we have also introduced the development of various CRISPR/Cas9 systems and discussed their future possibilities.

This study aimed to investigate the epidemiologic, clinical, pathological characteristics, and treatment of patients with Castleman disease (CD) in a single center in China. We retrospectively analyzed the data of 65 Chinese CD patients, divided into unicentric CD (UCD) and multicentric CD (MCD) groups, and also microscopic subtypes as hypervascular (HV), plasmacytic (PC) and Mixed. Based on whether HHV-8 infection existed, MCD was subdivided into HHV-8-associated MCD and idiopathic Castleman disease (iMCD). Detailed epidemiologic, clinicopathological, and treatment data were analyzed and discussed. Of total 65 patients (UCD 33, MCD 32), HV (81.8%) accounted for the most of UCD and total. More females in UCD (60.6%) and more males in MCD (65.6%) were observed. CD occurred in all age groups, most commonly in 40–49 years. The mean age of onset of total was 38.5 years with PC higher than HV (45.5 vs. 35.1 years, P = 0.0413). The median diagnosis delay of MCD was longer than that of UCD (3.00 vs. 1.25 months, P = 0.0436). Abdomen (39.4%) and neck (30.3%) were the most-seen locations of lymphadenopathy in UCD, with neck (65.6%) being predominant in MCD. Mean major diameter of specimens of UCD was greater than MCD (6.4 vs. 3.1 cm, P