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Cr(vi) reduction to Cr(iii) with electrochemical technique has been regarded as an effective method for the treatment of toxic Cr(vi) contaminated wastewater.

Urban land subsidence threatens the safety of urban buildings and people’s lives. The time series interferometric synthetic aperture radar (InSAR) technology can provide us with large-area, high-resolution, and high-precision ground deformation monitoring. In this study, the time series InSAR technology and the strategy with long- and short-time baseline networking are used to obtain the surface deformation along the line of sight of Nanchang City based on the six-year (from December 2015 to December 2021) Sentinel-1 data. Longer datasets and better baseline strategies allow us to obtain more stable deformation results of Nanchang City than other researchers. The results of surface deformation show that the overall surface of Nanchang City is stable, but there are several obvious subsidence funnels. We carried out a field survey on four areas with significant surface subsidence. We considered that these subsidence areas may be related to soil compaction, building construction, and groundwater extraction. Based on the surface deformation results around the subway line, we analyzed the impact of subway construction on the surface along the line and identified the sections that need to be focused on by the managers to prevent the deformation area from affecting the surrounding buildings and subway line operation safety.

The helicity asymmetry parameter τ in the Cameron decomposition indicates the degree to which a scatterer deviates from being an ideal symmetric scatterer. However, the solving procedure of τ can only be expressed in terms of single-look Sinclair scattering matrix. In this paper, we extend the helicity τ to a generalized helicity parameter τg, which is appropriate for both the single-look and multi-look PolSAR data. For single-look data, the generalized helicity τg is equivalent to the previous helicity τ. In addition, we investigate the relationships among the classical helix/helicity definitions, including the Cameron helicity, the Krogager helix component, and the Yamaguchi helix component. To achieve this, we represent the Cameron and Krogager decompositions in terms of the unified CTD model in the format of coherency matrix and revise the expression of Krogager decomposition contributions in function of Huynen parameters. Results show that essentially the Cameron helicity and Krogager helix are two kinds of representation of reflection asymmetry under the same decomposition model, and the Yamaguchi helix contribution is always larger than the Krogager helix contribution. Single-look PolSAR data from L-band ESAR is used for demonstration in this paper. Several multi-look datasets are generated by 1×3, 3×3, 3×5, 5×5, 5×7, 7×7, 7×9, and 9×9 boxcar average. Two techniques are taken to mitigate reflection symmetry assumption based on helix component and helicity angle respectively. It will be shown that the technique with the generalized helicity τg performs best in terms of efficiency and stability.

The clinical success of T-cell receptor (TCR)-based immunotherapy depends on the efficacy and specificity of TCRs. Naturally occurring TCRs have limited anti-tumor potency due to their low affinity for tumor antigens. Affinity enhancement is a promising strategy to generate highly potent TCRs. However, it is concerned that affinity-enhanced TCRs are prone to lose specificity. We isolated low affinity TCRs specific for NY-ESO-1157-165/HLA-A*02:01 from peripheral blood mononuclear cells of healthy donors. An affinity-enhanced TCR candidate with optimal affinity and specificity was generated using phage display and an extensive set ofin vitroandin vivoassays. Alanine scanning mutagenesis showed that the TCR candidate retained specificity by making extensive contacts to the side chains of NY-ESO-1157-165peptide. Adoptive transfer of T cells engineered with this candidate (termed TAEST16001) significantly inhibited tumor growth in subcutaneous, metastatic, and patient-derived xenograft (PDX) mouse tumor models. This study demonstrates that sophisticated engineering and screening techniques can be utilized to generate a clinical candidate TCR with potent anti-tumor activity without losing specificity. TAEST16001 was approved by the Center for Drug Evaluation (CDE) as the first TCR-based immunotherapy clinical trial in China (ClinicalTrials.govIdentifier:NCT03159585).

Oncolytic virotherapies are perceived as remarkable immunotherapies coming into view and represent highly promising cancer treatments, yet to figure out its specific immune responses and underlying barriers remains critical. Albeit recent studies have demonstrated that oncolytic viruses (OVs) could fine tune tumor microenvironment (TME) to elicit tumor suppression mainly due to effective T-cell responses, the interaction between suppressive T cells and OVs is barely undetermined. Herein, we found that regulatory T cells (Treg cells) were increased in the TME following systemic administration of oncolytic virus M1 along with the higher expression of relative cytokines and chemokines in both mouse RM-1 prostatic carcinoma model and mouse B16F10 melanoma model. Besides, Treg cells expressed high levels of CD25 post-M1 treatment, and its suppressive effect on CD8+ T cells was also elevated. Depletion of Treg cells in M1-treated groups significantly reinforced antitumor effect of M1. Specific targeting of Treg cells using cytotoxic T lymphocyte-associated protein 4 (CTLA-4) antibody (Ab) in combination with M1 treatment elicited a more profound tumor suppression and longer overall survival time than M1 alone in both tumor models. Moreover, CTLA-4 Ab further aggrandized antitumor immune response elicited by M1, including increased infiltration of CD45+ immune cells and CD8+ or CD4+ T lymphocytes, decreased ratio of Treg cells to CD4+ T lymphocytes, the intensified lymphocytotoxicity and elevated secretion of cytotoxic cytokines like interferon-γ, granzyme B and perforin. Therefore, our findings constituted a suggestive evidence that targeting Treg cells in M1-based oncolytic virotherapy may achieve a highly response in clinical cancer research.

Accumulating evidence supports the existence of glioma stem cells (GSCs) and their critical role in the resistance to conventional treatments for glioblastoma multiforme (GBM). Differentiation therapy represents a promising alternative strategy against GBM by forcing GSCs to exit the cell cycle and reach terminal differentiation. In this study, we demonstrated that cAMP triggered neuronal differentiation and compromised the self-renewal capacity in GSCs. In addition, cAMP induced negative feedback to antagonize the differentiation process by activating β-catenin pathway. Suppression of β-catenin signaling synergized with cAMP activators to eliminate GSCs in vitro and extended the survival of animals in vivo. The cAMP/PKA pathway stabilized β-catenin through direct phosphorylation of the molecule and inhibition of GSK-3β. The activated β-catenin translocated into the nucleus and promoted the transcription of APELA and CARD16, which were found to be responsible for the repression of cAMP-induced differentiation in GSCs. Overall, our findings identified a negative feedback mechanism for cAMP-induced differentiation in GSCs and provided potential targets for the reinforcement of differentiation therapy for GBM.

Over the last decade, oncolytic virus (OV) therapy has shown its promising potential in tumor treatment. The fact that not every patient can benefit from it highlights the importance for defining biomarkers that help predict patients’ responses. As particular self-amplifying biotherapeutics, the anti-tumor effects of OVs are highly dependent on the host factors for viral infection and replication. By using weighted gene co-expression network analysis (WGCNA), we found matrix remodeling associated 8 (MXRA8) is positively correlated with the oncolysis induced by oncolytic virus M1 (OVM). Consistently, MXRA8 promotes the oncolytic efficacy of OVM in vitro and in vivo. Moreover, the interaction of MXRA8 and OVM studied by single-particle cryo-electron microscopy (cryo-EM) showed that MXRA8 directly binds to this virus. Therefore, MXRA8 acts as the entry receptor of OVM. Pan-cancer analysis showed that MXRA8 is abundant in most solid tumors and is highly expressed in tumor tissues compared with adjacent normal ones. Further study in cancer cell lines and patient-derived tumor tissues revealed that the tumor selectivity of OVM is predominantly determined by a combinational effect of the cell membrane receptor MXRA8 and the intracellular factor, zinc-finger antiviral protein (ZAP). Taken together, our study may provide a novel dual-biomarker for precision medicine in OVM therapy.

In this article, we develop two target parameters to model the interaction between a target and a polarization wave. The two parameters are the target ellipticity angle (TEA) and the target phase angle (TPA). The concept of reflection symmetry or rotation symmetry is used to explain the robustness of the estimation method and to show problems associated with other algorithms. C-band Radarsat-2 and L band ALOS PALSAR multi-look full polarimetric images are used to substantiate the parameters, and validate the effectiveness of them. In addition, the TEA and TPA are compared with $\alpha - \beta $ model and Touzi TVSM model for single-look polarimetric SAR data. Experimental results show that the two target parameters are beneficial supplements for interpreting the target scattering processes and separating buildings from other targets.

The assumption of reflection symmetry is one of the major deficiencies for model-based decompositions. The introduction of helix scattering components can mitigate some of the impact of this assumption while simultaneously generating some new negative power problems. The helix mechanism has been developed in the Krogager coherent target decomposition where there is no negative power problem. Why do these problems happen in model-based decompositions? In this paper, we review the Krogager decomposition based on the coherency matrix form of the unified CTD model and come to the conclusion that the imaginary part of $T_{23}$ is an overestimate of the helix contribution, which is the main cause of the problem. Furthermore, we review the techniques of symmetric scatterer transformation in the Cameron and Huynen decompositions and expand them to the multilook coherency matrix. Two new models of the nonlinear programming problem are proposed to get the transformed coherency matrix: 1) by subtracting the asymmetric component; and 2) by the procedure of con-diagonalization. A new parameter is established to measure the degree of reflection asymmetry of the coherency matrices. Experimental results in the L-band Airborne SAR (AIRSAR) San Francisco data show that the two new models can reduce the correlations between copolarized and cross-polarized channels significantly. In this case, the assumption of reflection symmetry is reasonable for the transformed coherency matrices, and negative power problems related to helix scattering no longer exist in the model-based decompositions; hence, the helix scattering component is not needed. Lastly, the Freeman and Durden decomposition has been applied to the transformed coherency matrices. Experimental results showed that the decomposition results can reflect the predominant characteristics of the ground objects.

This paper thoroughly compares the target phase angle (TPA) and Cloude-Pottier alpha angle. Firstly, this paper analyzes the relation between TPA and Cloude-Pottier alpha angle for single look complex (SLC) POLSAR data. Then, the comparison for multi-look complex (MLC) POLSAR data is investigated over different target types, including paralleled buildings, oriented buildings, forests, lawns, and water. The MLC POLSAR data was collected over Suzhou, China. in 2010 by the Radarsat-2. Experimental results validate that there exists a close relation between the TPA and Cloude-Pottier alpha angle. And it is also validated that the TPA could be used to describe the target scattering mechanisms.

This letter first analyzes the scattering features of civilian aircraft (CA) using high-resolution TerraSAR-X images of the Hong Kong International Airport based on the electromagnetic scattering theory. The main stable scattering features are found to be salient points. Then, a salient point vector (SPV) is proposed to describe the salient points. By adding two relaxation variables to the matching process, the SPV becomes both translationally and rotationally invariant over a certain orientation range. In addition, a recognition scheme is designed to validate the scattering analysis and the SPV descriptor. Finally, 43 test chips are collected from another TerraSAR-X image acquired in November 2013 in the same location with similar imaging parameters. The test chips are applied to validate the analysis, the SPV descriptor, and the recognition scheme. The results of the experiment indicate that the recognition rate of the Boeing 747 CA reaches 80% and that the scattering features of the aircraft are rotationally invariant to within at least 5 $^{\circ}$ . This research verifies the potential application of CA monitoring using high-resolution synthetic aperture radar images.

This paper investigates three target parameters, i.e., target orientation angle, target ellipticity angle, and target phase angle in L band AL O S PAL SAR full polarimetric data collected over Beijing, China. In experiments, the three target parameters are analyzed via histograms, distributed image, and the number of negative power pixels in Freeman decomposition with various compensations. Experimental results show that all the three target parameters have a Gaussian distribution histogram, and conform to the characters of different land covers. After compensation, negative power pixels in Freeman decomposition are dramatically reduced as compared with Freeman decomposition without any target compensations. It is also found that target orientation angle impact on the interaction strongest among the three target parameters, and target ellipticity angle impact on the interaction stronger than target phase angle.

Using the bottom-up method and Tapio model, we calculated the tourism energy consumption (EC) and corresponding carbon emission (CE) in Hubei of China, and analyzed the decoupling between the CE and tourism economy. The results showed the tourism CE was 111.84×104 t in 2001, and increased to 376.04×104 t in 2015, with the annual growth amount of 18.87×104t and rate of 9.05%, respectively. This denoted Hubei’s tourism was being thoroughly developed on the whole from 2001 to 2015. Then, the share of tourism transport CE was always not less than 62% during 2001-2015, which indicated tourism transport sector should be paid more attention to and be given more of corresponding mitigation countermeasures. Furthermore, tourism activities’ CE was always becoming larger and larger, with the increases of people’s living standard and leisure time. Thus, it was necessary to study on how to improve the efficiency of energy use, especially in the progress of tourism activities. Last, an overall weak decoupling relationship between tourism economy and the corresponding CE existed within Hubei in 2001-2015. Thus, the economic development mode of Hubei’s tourism industry was transforming to the low-carbon pattern expected by us, but it still needed to be continually strengthened.

It is necessary to calibrate polarimetric synthetic aperture radar (PolSAR) data in order to use the data for science applications. In this letter, we propose an improved algorithm to estimate the calibration parameters based on the Ainsworth algorithm and the Quegan algorithm. Since there is no approximation in the process of the parameter estimation, this algorithm can accurately solve all parameters, even if the crosstalk is high. To verify the effect of the proposed calibration algorithm, this letter analyzes the accuracy of the proposed algorithm with the simulated PolSAR data and Chinese airborne X-band PolSAR data. The results confirm that the proposed algorithm can provide a more stable and accurate solution to the crosstalk parameters.

Scientific Reports 6: Article number: 33100; published online: 09 September 2016; updated: 19 October 2016

Aiming at the cells’ differentiation phenomenon and senescence problem in liver tissue engineering, this work is designed to synthesize three different chargeable polymers (polypropylene acid (PAAc), polyethylene glycol (PEG), and polypropylene amine (PAAm)) coimmobilized by the insulin-like growth factor 1 (IGF-1) and tumor necrosis factor-α (TNF-α). We explore the hepatocyte differentiation effect and the antisenecence effect of PSt-PAAm-IGF-1/TNF-α biomaterial which was selected from the three different chargeable polymers in bone marrow mesenchymal stem cells (BMSCs). Our work will establish a model for studying the biochemical molecular regulation mechanism and signal transduction pathway of cell senescence in liver tissue engineering, which provide a molecular basis for developing biomaterials for liver tissue engineering.

Habitat destruction, a key determinant of species loss, can be characterized by two components, patch loss and patch fragmentation, where the former refers to the reduction in patch availability, and the latter to the division of the remaining patches. Classical metacommunity models have recently explored how food web dynamics respond to patch loss, but the effects of patch fragmentation have largely been overlooked. Here we develop an extended patch-dynamic model that tracks the patch occupancy of the various trophic links subject to colonization-extinction-predation dynamics by incorporating species dispersal with patch connectivity. We found that, in a simple food chain, species at higher trophic level become extinct sooner with increasing patch loss and fragmentation due to the constraint in resource availability, confirming the trophic rank hypothesis. Yet, effects of fragmentation on species occupancy are largely determined by patch loss, with maximal fragmentation effects occurring at intermediate patch loss. Compared to the spatially explicit simulations that we also performed, the current model with pair approximation generates similar community patterns especially in spatially clustered landscapes. Overall, our extended framework can be applied to model more complex food webs in fragmented landscapes, broadening the scope of existing metacommunity theory.

A method to estimate absolute phase of the target, and phase compensation for the coherence matrix are introduced in this paper. The absolute phase of a target relates with the generator of target local shape, and with the the attenuation coefficients of vertical and horizontal polarimetric wave. The effectiveness of phase compensation is validated via Yamaguchi decomposition with phase compensation of Radarsat-2 full polarimetric data collected over Suzhou City, China. The estimation of absolute phase of target and the phase compensation are validated and benefit to correctly interpret the scattering mechanisms of targets, with decreasing the number of negative power pixels.

This paper proposes an improved four-component scattering decomposition scheme with modified double-bounce scattering model for the analysis of polarimetric synthetic aperture radar (POLSAR) data. In the Yamaguchi decomposition, it occurs occasionally for some pixels with negative surface scattering power Ps and/or negative diplane scattering power Pd because the whole HV cross-polarized component is assigned to volume scattering due to vegetation; and it is also difficult to discriminate man-made buildings not orthogonal to the radar LOS from vegetation. In advance the conditions of the emergence of negative powers in the Yamaguchi decomposition are given out, and three corresponding processing methods adopted in many improved four-component target decompositions are reviewed in the paper. Then the expression of the coherency matrix of distributed dielectric dihedral corner reflectors is derived. The expression demonstrates that distributed dielectric dihedral corner reflectors also will generate HV cross-polarized component. The new target decomposition utilizes the new double bounce model of distributed dielectric dihedral corner reflectors instead of the original one adopted by the Freeman and Yamaguchi decompositions. In order to solve the new decomposition, we introduce normalize circular-pol correlation coefficients to characterize the percentage of HV scattering component generated by distributed dielectric dihedral corner reflectors. An airborne L band quad-pol data acquired by DLR ESAR sensor over Oberpfaffenhoffen in German are applied to the improved decomposition scheme. Experimental results demonstrate that the new decomposition method can reduce the pixels with negative powers and obtain correct scattering mechanisms of non-reflection structures not paralleled to the flight path.

This paper presents a polarimetric SAR interferometric SAR data analysis based on ESPRIT algorithm and three-stage inversion algorithm. The formulations of ESPRIT algorithm and three stages inversion algorithm are presented firstly. The experimental results based on ESPRIT algorithm and three-stage algorithm have been compared and analyzed then. And we point out that direct conversion of the retrieved height of the scattering center corresponding to a single polarimetric channel to the forest height, will lead to underestimation. Therefore, it is important for the conversion to be carried out on the basis of a coherence scattering model of forest, which expresses radar observations in terms of a small number of vegetation and underlying-surface parameters. The experiment data is from PolSARpro software at L band.

In 1996, Cameron proposed an approach to decompose an arbitrary polarization scattering matrix into three orthogonal components, including nonreciprocal scattering component, maximum symmetric scattering component, and minimum symmetric scattering component. In this paper, based on the analysis of the characteristics of the maximum symmetric scattering component and the minimum symmetric scattering component in Cameron decomposition, a unified three-component scattering model for polarimetric coherent target decomposition is proposed. Pauli decomposition, SDH decomposition and Cameron decomposition can be expressed as a simplified form of the unified model with some certain restriction respectively. In addition, we can prove that SDH decomposition and Cameron decomposition to be equivalent by verification of restrictions consistency.