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China successfully launched the Atmospheric Environment Monitoring Satellite (AEMS) equipped with an Atmospheric Carbon Dioxide Lidar (ACDL) on April 16, 2022, which is the world's first satellite based on Integrated Path Differential Absorption (IPDA) technique to detect the atmospheric CO 2 column-weighted dry-air mixing ratio (XCO 2). In order to accurately and quickly process the AEMS measurements, we proposed a systematic retrieval algorithm for the AEMS ACDL and conducted two airborne campaigns to validate its performance. The first airborne campaign was conducted in the land-sea interface region of northeast China in 2019. The CO 2 retrieval algorithm distinguished significant horizontal XCO 2 gradients over different underlying surfaces and obtained an apparent XCO 2 enhancement of 8–18 ppm between the urban and forests. The CO 2 retrievals not only demonstrated the excellent detection capability of the ACDL for carbon sources and sinks, but also proved the feasibility of the retrieval algorithm in complex terrain and variable atmospheric conditions. The second airborne experiment was conducted in 2021 in the interior desert region of China, which is an excellent flight field to explore the accuracy and precision limits of the retrieval algorithm. We validated the XCO 2 retrievals with the airborne in-situ CO 2 profiles and demonstrated that the XCO 2 accuracy and precision were 0.29 ppm and 0.63 ppm with 1.5-km averages over the desert surface, indicating the accuracy of the retrieval algorithm. The hard target elevation (HTE) retrieval validation results indicate that the IPDA lidar ranging precision is 0.69 m and 6.29 m for the ocean and land surface, respectively. In addition, further analysis combined with the space-borne IPDA lidar simulator showed high consistency in CO 2 precision between airborne measurements and simulation results in East Asia, demonstrating the robustness of the retrieval algorithm at continental scales. • A systematic CO 2 retrieval algorithm is provided for China's AEMS space mission. • Performance of the retrieval algorithm is assessed by airborne campaigns. • The precision of the CO 2 retrievals is 0.63 ppm, validated with an in-situ sensor. • Recognize an apparent CO 2 enhancement of 8–18 ppm between carbon source and sink. • The robustness of the retrieval algorithm is confirmed at continental scales. [ABSTRACT FROM AUTHOR]

A large number of experimental and theoretical investigations of carbon dioxide (CO) spectra have been conducted since the most recent update of the High-Resolution Transmission Molecular Absorption (HITRAN) database. To maintain optimal parameters, the HITRAN 2004 CO line list has been completely replaced by HITRAN 2008 data in the near-infrared region from 4300 cm to 7000 cm. To examine the effect of this change on the retrieval of CO vertical column data from reflected sunlight spectra in the 1.61-µm spectral window, synthetic measurements for a given atmospheric state and instrument setup were generated and compared using radiative transfer model with the line-transition parameters from the HITRAN 2004 and 2008 databases. Simulated retrievals were then performed based on the optimal estimation retrieval theory. The results show that large systematic errors in atmospheric CO column retrievals were induced by the differences in the HITRAN laboratory line parameters in the 1.61-µm region. The retrieved CO columns were underestimated by >10 ppm using the HITRAN 2004 data, and improvements resulting from the use of the improved HITRAN database were more pronounced at a higher spectral resolution. [ABSTRACT FROM AUTHOR]

The Fourier Transform Spectrometer (FTS) at the Beijing Satellite Meteorological Ground Station observed XCO2 (the dry carbon dioxide column) from 2 March 2016 to 4 December 2018. The validation results of ground-based XCO2, as well as GOSAT, OCO-2, and TanSat XCO2, show that the best temporal matching setting for ground-based XCO2 and satellite XCO2 is ±1 h, and the best spatial matching setting for GOSAT is 0.5° × 0.5°. Consistent with OCO-2, the best spatial matching setting of TanSat is 5° × 5° or 6° × 6°. Among GOSAT, OCO-2, and TanSat, the satellite observation validation characteristics near 5° × 5° from the ground-based station are obviously different from other spatial matching grids, which may be due to the different observation characteristics of satellites near 5° × 5°. To study the influence of local CO2 sources on the characteristics of satellite observation validation, we classified the daily XCO2 observation sequence into concentrated, dispersive, increasing, and decreasing types, respectively, and then validated the satellite observations. The results showed that the concentrated and decreasing sub-datasets have better validation performance. Our results suggest that it is best to use concentrated and decreasing sub-datasets when using the Beijing Satellite Meteorological Ground Station XCO2 for satellite validation. The temporal matching setting should be ±1 h, and the spatial matching setting should consider the satellites observation characteristics of 5° × 5° distance from the ground-based station. [ABSTRACT FROM AUTHOR]

Abstract: Daily total suspended particulate (TSP), particle size smaller than 100μm and particle size smaller than 2.5μm (PM2.5) aerosol samples were collected at two sites in Shanghai in four seasons from September 2003 to January 2005. Concentrations of the water-soluble ions (SO4 2−, NO3 −, Cl−, F−, PO4 3−, HCOO−, CH3COO−, NO2 −, MSA, C2O4 2−, NH4 +, Ca2+, Na+, K+, Mg2+) were measured for a total of 202 samples. Daily TSP and PM2.5 mass concentrations ranged from 66.1 to 666.8μgm−3 and 17.8 to 217.9μgm−3, with annual average concentrations of 230.5 and 94.6μgm−3, respectively. The sum of ions contributed an average of 26% and 32% of TSP and PM2.5 mass concentrations, respectively. In PM2.5, the concentration of the major ions followed the order of SO4 2−>NO3 −>NH4 +>Cl−>Ca2+>K+, while in TSP was SO4 2−>NO3 −>Cl−>Ca2+>NH4 +>Na+. These major ions were mainly in the form of (NH4)2SO4, Ca(NO3)2, CaCl2, and CaSO4 in aerosol particles. The aerosol was slightly acidic in the fine particle size range, and alkaline in the coarse mode. Seasonal variation of ion concentrations was significant, with the highest concentrations observed in winter and spring and the lowest in summer and autumn. Three types of air masses, i.e. marine, mixing, and continental, were frequently observed, and their distribution in four seasons might result in the clear seasonal variation. It is Shanghai that has the highest NO3 −/SO4 2− value among all of those cities in China, indicating that as the biggest city in China the mobile source of the air pollution becomes more and more predominant. However, stationary emissions were still the dominant source in Shanghai indicated by the NO3 −/SO4 2− ratio of lower than 1. The formation of NO3 − was largely from the gas-phase photochemical reaction in the cold season, and from the heterogeneous reaction in the warm season, while the formation of SO4 2− might be from the heterogeneous reaction in the entire year round. NH4 +, K+, Cl−, NO3 −, and SO4 2− were mainly influenced by the anthropogenic emissions in land, meanwhile Cl− and SO4 2− might be partly influenced by the sea. Na+, Mg2+, and Ca2+ were derived from both inland crustal and marine sources. Chloride depletion was found especially in summer. The air pollution in Shanghai has proved to be under the influence of both the local emissions and the long-range transport from outside areas. [Copyright &y& Elsevier]

Particulate matter with an aerodynamic diameter of less than 1 μm (PM 1.0) can be extremely hazardous to human health, so it is imperative to accurately estimate the spatial and temporal distribution of PM 1.0 and analyze the impact of related policies on it. In this study, a stacking generalization model was trained based on aerosol optical depth (AOD) data from satellite observations, combined with related data affecting aerosol concentration such as meteorological data and geographic data. Using this model, the PM 1.0 concentration distribution in China during 2016–2019 was estimated, and verified by comparison with ground-based stations. The coefficient of determination (R2) of the model is 0.94, and the root-mean-square error (RMSE) is 8.49 μg/m3, mean absolute error (MAE) is 4.10 μg/m3, proving that the model has a very high performance. Based on the model, this study analyzed the PM 1.0 concentration changes during the heating period (November and December) in the regions where the "coal-to-gas" policy was implemented in China, and found that the proposed "coal-to-gas" policy did reduce the PM 1.0 concentration in the implemented regions. However, the lack of natural gas due to the unreasonable deployment of the policy in the early stage caused the increase of PM 1.0 concentration. This study can provide a reference for the next step of urban air pollution policy development. • Use stacking machine learning algorithm and satellite data to reconstruct PM 1.0. • "Coal-to-gas" policy led to PM 1.0 concentration changes, notably in 2017 and 2019. • Provides valuable insights for mitigate air pollution in Chinese cities. [ABSTRACT FROM AUTHOR]

Using satellite observation data to retrieve atmospheric pollution parameters has become a common technique in the field of remote sensing. Compared with the traditional single-angle and only intensity detection signal loads, multi-angle with/or polarized remote sensing observation instruments provide new ideas for detecting aerosol parameters. Nowadays, multi-angle detection technology and the development of advanced detection loads have become one of the main directions in the field of remote sensing. From the perspective of aerosol characterization from remote sensing measurements, this paper first summarized the information of typical instruments among the development of airborne, space-borne and ground-based detections in various countries. Second, taking the Multi-Angle Imaging SpectraRadiometer (MISR) aboard on Terra, Polarization and Anisotropy of Reflectance for Atmospheric Sciences Coupled with Observations from a LiDAR (PARASOL)/POLDER and Directional Polarized Camera aboard on Gaofen-5 (GF-5/DPC) respectively as representatives of the multi-angle only intensity signal (MAOI, hereafter) and multi-angle polarized signal (MAPS, hereafter), using AERONET/CE-318 as the representative of ground-based remote sensing observations, respectively introduced the current research status of their aerosol characteristics in recent years from three perspectives of data set accuracy evaluation, inversion algorithm improvement and product application. To be specific, 1) the improvements based on MAOI are mainly reflected in the optimization of the aerosol model, and the difficulty lies in how to express the surface contribution by using the empirical orthogonal function. The narrow swath and coarse temporal resolution of MISR determine the rarely popular as MODIS. A higher resolution at 4.4km×4.4 km provide data support for investigating the evolution trends of regional aerosol properties at the regional scale. 2) In addition to establish more approximate aerosol models and acute surface reflectance functions by MAPS, the method of optimal estimation and multi-variate statistical optimal data have been developed to retrieve fine AOD, particle distribution, polarized phase function and etc. Finally, based on the above investigation, it is found that, 1) the planned payloads not only add polarization signal, but also take the importance of multi-spectral into consideration, particularly in near-infrared and short-wave infrared channels, which makes more contributions to improve the retrieval information for coarse particles. 2) The Lookup table-based inversion methods require to refine more appropriate aerosol types and precise surface reflectance relationship, but for the rich information content of hyperspectral load, the inversion efficiency of this method needs to be improved. 3) In addition, the complement of MAOI and MAPS and the fusion of inversion algorithms is also a way to improve the overall inversion accuracy of aerosol characteristics. 4) While improving load performance and enhancing matching inversion algorithms, it is also necessary to vigorously develop calibration techniques for polarized loads, and stable and high-precision calibration coefficients provide the basis for the development of secondary products and the application of tertiary products. 5) domestic MAPS instrument as well as polarization lidar need to be put on the agenda. • The information of typical instruments among the development of airborne, space-borne and ground-based detections in various countries are summarized. • The planned payloads with polarization signal, multi/hyper-spectral are beneficial to coarse particles retrieval. • The fusion of multi-inversion algorithms is also a way to improve the overall inversion accuracy of aerosol characteristics. • Except for improving the retrieval algorithm, it is also necessary to develop calibration techniques for polarized loads. [ABSTRACT FROM AUTHOR]

Abstract Pointing information is decisive to solving precise profile retrieval issues from occultation measurements. Research regarding stratospheric O 3 hole in Antarctic and surface O 3 pollution would significantly benefit from massive occultation measurements. A neural network aided pointing information determination approach, in terms of tangent heights, is proposed to address issues requiring fast and easy-to-use determined tangent heights. The geometrical triangular iteration (GTI) algorithm in this work is based on N 2 absorption microwindows, and several treatments (e.g., tangential stride generator and triangular-net optimization) are adopted. In addition, LSTM is employed to reduce time consumption and increase accuracy. Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS) in-flight measurements are used to assess this approach. The comparison between the proposed algorithm and eight official products indicates a promising performance. Correlation coefficient for each orbit is greater than 0.99. The processing time is about 16.6 min per orbit with an average cost of ∼ 0.06. The introduction of LSTM technique demonstrates an approximate 28.49% better result, with less computation time. It costed less than 30 s to determine eight orbit tangent heights. In general, although minor issues remain, this LSTM-aided GTI algorithm is applicable in industry. [ABSTRACT FROM AUTHOR]

• Value-added & fully utilization of CWs into building materials. • Addition of PA significantly improved the smoke suppression performance of WPBs. • Increasing of PA contributes to excellent integrated performance of WPBs. • Admirable method promoting the value-added & fully utilization of CWs. • Excellent comprehensive performance promoting WPBs application in green buildings. Construction wastes (CWs) were utilized in this work as the feedstock for manufacturing wasted-based particle boards (WPBs). Results revealed that phytic acid (PA), as a natural and sustainable fire retardant, imparts the WPBs excellent flame retardancy and smoke suppression. The hydrogen bonds network formed among PA, waste particles, and adhesive improves the stress transferring of WPBs when subjected to load, thus elevating the modulus of elasticity and inner bonding strength of PA-treated WPBs. We believe that the as-proposed recycling methods promote the value-added utilization of CWs, and it is also beneficial for realizing the recycling of timber architectures. [ABSTRACT FROM AUTHOR]

• Quantifying CO 2 emissions from power plants could be conducted by LiDAR data. • A CO 2 emission quantification model with high applicability was developed. • Quantify model has self-adjustment function in monitoring CO 2 emission. Accurate reporting of point source emissions of CO 2 is fundamental to addressing climate change. Currently, bottom-up verification methods based on inventory statistics face significant challenges in this area. Satellite remote sensing has emerged as a promising approach for cost-effective global-scale verification of point source emissions, with spaceborne LiDAR offering high spatial resolution ideal for this purpose. However, the inversion of CO 2 emissions from spaceborne LiDAR CO 2 concentration observations requires urgent attention, as existing methods heavily rely on prior information in diffusion models and the accuracy of meteorological data. In this work, a novel emission inversion method based on genetic algorithms and trust-region techniques is proposed to estimate CO 2 emissions from point sources using spaceborne LiDAR observations. A comparison between the CO 2 emission rates calculated from actual airborne LiDAR data (as a prototype of spaceborne LiDAR) and emission inventories for the Suizhong power plant showed a deviation of less than 7.0%. Observing system simulation experiment (OSSE) demonstrated that using DQ-1 (spaceborne LiDAR) observation data as input, the relative error of emission rates would be less than 0.6% when the distance between the emission source and the observation footprint is less than 10 km. Furthermore, the developed model mitigates the impact of uncertainties in meteorological data and IPDA (Integrated-Path Differential Absorption) LiDAR measurements on the final emission quantification. The proposed approach is expected to enable DQ-1 to provide affordable and accurate carbon verification services for over 20.0% of the world's strong point source emissions. [ABSTRACT FROM AUTHOR]

Abstract The first Chinese Carbon Dioxide Observation Satellite Mission (TanSat), which was launched on December 21, 2016, is intended to measure atmospheric CO 2 concentration. The high spectral resolution (0.044 nm) and high SNR (360 at 15.2 mW m−1 sr−1 nm−1) measurements in the region of the O 2 -A band of the Atmospheric Carbon dioxide Grating Spectroradiometer (AGCS) module onboard TanSat make it possible to retrieve solar-induced chlorophyll fluorescence (SIF) from TanSat observations at the global scale. This paper aims to explore the potential of the TanSat data for global SIF retrieval. A singular vector decomposition (SVD) statistical method was employed to retrieve SIF using radiance over a micro spectral window (∼2 nm) around the Fe Fraunhofer lines (centered at 758.8 nm). The global SIF at 758.8 nm was successfully retrieved with a low residual error of 0.03 mW m−1 sr−1 nm−1. The results show that the spatial and temporal patterns of the retrieved SIF agree well with the global terrestrial vegetation pattern. The monthly SIF products retrieved from the TanSat data were compared with other remote sensing datasets, including OCO-2 SIF, MODIS NDVI, EVI and GPP. The overall consistency between TanSat and OCO-2 SIF products (R 2 = 0.86) and the consistency of the spatial patterns and temporal variations between the TanSat SIF and MODIS vegetation indices and GPP enhance our confidence in the potential and feasibility of TanSat data for SIF retrieval. TanSat, therefore, provides a new opportunity for global sampling of SIF at fine spatial resolution (2 km × 2 km), thus improving photosynthesis observations from space. [ABSTRACT FROM AUTHOR]

Interface-interaction induced self-healing and self-adhesive are a gem–like attribute inspired by our Mother Nature. Biocompatible gelatin methacrylate (GelMA) hydrogels exhibit tunable mechanical properties which are favorable in biomedical applications. However, it is difficult to integrate high stiffness, super-elasticity, large deformability and self-healing property together. Here, we report a GelMA-based double-network (DN) hydrogel with above properties by utilizing tannic acid (TA) as a multi-functional H-bond provider. We first investigated the morphological and mechanical properties' changes of GelMA over different TA's concentrations and treating times. In comparison to pristine GelMA hydrogel (10% w/v), the GelMA-TA hydrogels presented significant increase in ultimate stress (4.3-fold), compressive modulus (2.5-fold), and especially in elongation (6-fold). Adhesion properties of GelMA-TA can be tuned by TA and have been proven to be water-resistant. To test gels' feasibility in vivo , we applied GelMA-TA gels to close skin wound and gastric incision without suture. The results indicated the gels had the capabilities of promoting wound healing with superior tissue restoration and minimal tissue adhesion. Furthermore, integrated with carbon nanotubes, the GelMA-TA-carbon nanotube gel was an alternative self-healing electric skin with strain-sensitive conductivity. This work demonstrated a strategy to yield mechanically strong hydrogel adhesives for innovative biomedical applications. [ABSTRACT FROM AUTHOR]

Atmospheric SO has a significant impact on the urban environment and global climate. Band Residual Difference Algorithm (BRD) and Differential Optical Absorption Spectroscopy (DOAS) were used respectively by NASA and ESA science team to derive SO columns from satellite observations, but there are few studies on the comparison and validation of BRD and DOAS SO retrievals under the same observation conditions. In this study, the radiative transfer model SCIATRAN was firstly used to validate the accuracies of BRD and DOAS SO retrievals, and analyse the uncertainty of SO retrieval caused by band selection, O3 absorption, aerosol, surface reflectance, solar and viewing zenith angle. Finally, BRD and DOAS algorithms were applied to the same radiances from satellite observations, and comparisons of BRD and DOAS SO retrievals were conducted over volcanic eruption and North China. Results show that, for the case with low SO columns, BRD SO retrievals have higher retrieval accuracy than DOAS, but typical seasonal variation with high SO column in winter and low in summer can be more clearly discernible in DOAS SO retrievals than BRD from satellite observations. For the case with high SO columns, the differences between BRD (310.8-314.4 nm) and DOAS (315-327 nm) retrievals are large, and the value and accuracy of BRD (310.8-314.4 nm) SO retrievals are lower than those of DOAS (315-327 nm) retrievals. Compared with the SO inputs in forward model, both BRD (310.8-314.4 nm) and DOAS (315-327 nm) SO retrievals are underestimated for the case with high SO columns. The selection of wavelength range can significantly affect the accuracy of SO retrieval. The error of BRD SO retrieval from 310.8-314.4 nm is lower than other bands in the ultraviolet spectral region (306-327 nm). The increase of wavelength in the ultraviolet spectral region 306-330 nm can reduce the underestimation of DOAS SO retrievals in the case of high SO column, but slight overestimation of SO retrieval is found from the 315-327 nm range in the case of low SO column. The values of BRD and DOAS SO retrieval decrease with atmospheric O column and aerosol optical depth increasing, but increase with surface reflectance increasing. Large solar zenith angle and viewing zenith angle can introduce more errors to the BRD and DOAS SO retrievals. This study is important for the improvement of retrieval algorithm and the application of SO products from satellite observations. [ABSTRACT FROM AUTHOR]

The spectra of O A-band (0.76 μm) and CO near-infrared emissions (1.6 μm) are simulated by the SCIATRAN radiative transfer model (V3.1.23), and compared with those observed by GOSAT-FTS (Greenhouse gases Observing SATellite-Fourier Transform Spectrometer). Systematic deviations between the observed and simulated spectra are found to exist, especially for the O A-band. The discrepancies are characterized by their mean differences averaged over the observed spectral ranges. A correction is applied to the observed GOSAT-FTS L1B (V141.141) spectra by scaling the spectral intensity measured by TANSO-FTS (Thermal and Near infrared Sensor for carbon Observation Fourier Transform Spectrometer) onboard GOSAT. The average columnar CO concentrations (XCO) are retrieved from the observed and the corrected GOSAT-FTS spectra by using the SCIATRAN inversion algorithm. Compared with the GOSAT-FTS L2 XCO data products retrieved from the observed spectra of GOSAT-FTS, the SCIATRAN retrievals from the corrected spectra show a much better agreement, with the relative error less than 1%. But the results of GOSAT TANSO-FTS (V161.160) show smaller residuals than GOSAT TANSO-FTS (V141.141) without mean residual correction. The results indicate that the mean residual correction would increase the precision of XCO retrieval for spectra with systematic deviations. [ABSTRACT FROM AUTHOR]

This study developed an inversion algorithm for the CO 2 -sounder instrument to be launched on a Chinese satellite. By using the L1B spectral data of the Greenhouse gases Observing Satellite (GOSAT) as input, the simulation results of the column averaged CO 2 dry air mole fraction (XCO 2 ) retrieved from the CO 2 -sounder algorithm were obtained and compared with the GOSAT L2 XCO 2 products for different seasons and geolocations. The simulation data showed a tendency to be less than the GOSAT L2 data, but the two data sets were generally in agreement with a global mean difference of −4.05 ± 6.06 ppm. For the matched data pairs, 51% had their relative differences less than 1% in absolute value, and 76% less than 2%. The seasonal and latitudinal variations of the XCO 2 differences were also investigated, and the largest discrepancy was found in the desert areas with the relative differences of about 3%–4%. These results suggested that better consistency between the two data sets could be achieved if more realistic observational parameters instead of model values were used in the simulation. These parameters included the a priori profiles of atmospheric temperature, concentrations of CO 2 , O 2 , and H 2 O, surface reflectance, aerosol and cloud indices, etc. [ABSTRACT FROM AUTHOR]

Based on the optimal estimation method, the global carbon dioxide hyperspectral remote sensing inversion system GF_VRTM is established for the greenhouse gas carbon dioxide remote sensing detection of GF-5 satellite. The period of April 2013 to April 2014 GOSAT-FTS observations over TCCON site Tsukba are simulated by GF_VRTM, and the retrieval results are compared with GOSAT-FTS products and TCCON XCO 2 . The mean residuals between the GOSAT-measured and GF_VRTM-simulated spectra are nearly zero for the O 2 -A band and WCO 2 band over the spectral ranges. The average and standard deviation of ΔXCO 2 between GF_VRTM retrievals and GOSAT-FTS L2 products are evaluated to be −1.63 and 1.78 ppm for the whole period, and the average and standard deviation of ΔXCO 2 between GF_VRTM retrievals and TCCON data are evaluated to be −0.38 and 2.25 ppm for the whole period. The accuracy of the GF_VRTM retrieval is less than 1% based on the validation results with GOSAT-FTS L2 products and TCCON data. [ABSTRACT FROM AUTHOR]

The global carbon dioxide hyperspectral remote sensing inversion system GF_VRTM is established for the greenhouse gas carbon dioxide remote sensing detection of GF-5 satellite. The validation and error analysis of global inversion is performed by using GF_VRTM with 21 June 2013 observation data of GOSAT-FTS in this study. The simulation results show that the CO 2 averaged column concentrations (XCO 2 ) overall trends are basically identical between GF_VRTM retrievals and GOSAT-FTS observations. There are 138 exposure points in whole observation points, and the relative error less than 2% is about 85%. The mean square error is 5.00 ppm, but the global average error is 1.09 ppm. If the assumption that GOSAT-FTS observation data is true, GF_VRTM satisfies the average precision requirements (less than 1%) of XCO 2 global inversion. For the results of the comparison, the minimum error scenario and maximum error scenario are selected for error analysis. Error sources are smooth error, measurement noise error, the forward model parameter error and forward model error, respectively. For the minimum error scenario and maximum error scenario, the relative error of XCO 2 inversion caused by smooth error and measurement noise error are 0.44% and −1.62%, respectively, and the relative error of XCO 2 inversion caused by the forward model parameter error are −0.43% and −1.53%, respectively. At the same time, the forward model error is ignored. [ABSTRACT FROM AUTHOR]

Due to urbanization and industrialization, PM 2.5 (particulate matter with a diameter less than 2.5 μm) pollution has become a serious environmental problem. The low spatial resolution and insufficient coverage of PM 2.5 observation stations affect research on pollution causes and human health risks. With the launch of FY-4A, new generation of Chinese geostationary weather satellites, it is possible to obtain PM 2.5 with high temporal and spatial resolution covering all China. In this study, FY-4A top-of-the-atmosphere reflectance data, meteorological factors, and geographic information were input into the deep forest (DF) model to obtain the hourly PM 2.5 in China. The samples based 10-fold cross validation of DF with an hourly R2 of 0.83–0.88, and the root mean square error is 8.81–14.7 μg/m3, while the R2 of the 10-fold cross validation result based on sites was 0.77. The monthly (R2 = 0.98) and seasonal (R2 = 0.99) estimated results showed high consistency with the observations. Feature importance showed that the contribution of estimated features to the model varies with regions and seasons. Estimation results indicated the substantial spatiotemporal differences in PM 2.5 , and pollution was the highest between 09:00–10:00 and then gradually decreased. Regions with highest pollution of PM 2.5 in China were mainly distributed in the Tarim Basin and Central China. The pollution assessment results in China indicated that: 1) In more than 80% of the winter days PM 2.5 was higher than the World Health Organization interim target 3 (37.5 μg/m3); 2) The bimodal distribution of PM 2.5 indicated that there are obvious differences in pollution between cities and suburbs; 3) In autumn and winter, the regions where population-weighted PM 2.5 was higher than IT-3 were mainly in Beijing-Tianjin-Hebei, Central China, Guanzhong Plain, Sichuan Basin, and Yangtze River Delta. Our results showed that FY-4A has advantages of high resolution and coverage and thus shows great potential for estimating pollutants. • FY-4 TOAR data were used to estimate PM 2.5 covering the whole of China. • Deep forest model performed well, with an R2 of 0.83–0.88 and RMSE of 8.81–14.7 μg/m3. • Under different conditions, the contribution of features to the model changes. • PM 2.5 concentration showed bimodal distribution characteristics. • PM 2.5 on more than 80% of days in winter was higher than the WHO interim target 3. [ABSTRACT FROM AUTHOR]

Abstract: Solution polymerized styrene-butadiene rubber (SSBR) and SSBR with tert-Butylchlorodiphenylsilane (TBCSi, large-volume functional groups) at the two ends of macromolecular chains (T-SSBR) were prepared by anionic polymerization. The molecular structure parameters of T-SSBR and SSBR were characterized and the ratio of the amount of macromolecular chain ends connected with TBCSi to total macromolecular chain ends (i.e., end-capping efficiency) was calculated. The comprehensive properties of T-SSBR and SSBR composites filled with carbon black (CB) were investigated. The results showed that T-SSBR composites presented lower Payne effect (namely better CB dispersion) than those of SSBR composites, which led to decrease in hardness, internal friction, dynamic compression heat built-up and permanent set of T-SSBR composites, significant increase in tensile strength, elongation at break, tear strength and resilience of T-SSBR composites, and excellent balance between wet-skid resistance and rolling resistance. However, compared with SSBR composites, T-SSBR composites presented longer stress-relaxation time, bigger die-swell and higher apparent viscosity, as well as slightly inferior dynamic-cutting resistance. All the above, owing to the end-capping of TBCSi, which could immobilize the free chain ends of T-SSBR (i.e., to reduce the friction loss of molecular chains and create a greater degree of orientation in the force field), and adsorb CB, the comprehensive performances of T-SSBR were better than those of SSBR and T-SSBR terminated with styrene-TBCSi (TS-SSBR) were far superior to those of T-SSBR terminated with butadiene-TBCSi (TB-SSBR). Accordingly, the former was suitable for the tread of green tires. [Copyright &y& Elsevier]

The Ku-band scatterometer called CSCAT onboard the Chinese–French Oceanography Satellite (CFOSAT) is the first spaceborne rotating fan-beam scatterometer (RFSCAT). This paper performs sea ice monitoring with the CSCAT backscatter measurements in polar areas. The CSCAT measurements have the characteristics of diverse incidence and azimuth angles and separation between open water and sea ice. Hence, five microwave feature parameters, which show different sensitivity to ice or water, are defined and derived from the CSCAT measurements firstly. Then the random forest classifier is selected for sea ice monitoring because of its high overall accuracy of 99.66% and 93.31% in the Arctic and Antarctic, respectively. The difference of features ranked by importance in different seasons and regions shows that the combination of these parameters is effective in discriminating sea ice from water under various conditions. The performance of the algorithm is validated against the sea ice edge data from the EUMETSAT Ocean and Sea Ice Satellite Application Facility (OSI SAF) on a global scale in a period from 1 January 2019 to 10 May 2021. The mean sea ice area differences between CSCAT and OSI SAF product in the Arctic and Antarctic are 0.2673 million km2 and −0.4446 million km2, respectively, and the sea ice area relative errors of CSCAT are less than 10% except for summer season in both poles. However, the overall sea ice area derived from CSCAT is lower than the OSI SAF sea ice area in summer. This may be because the CSCAT is trained by radiometer sea ice concentration data while the radiometer measurement of sea ice is significantly affected by melting in the summer season. In conclusion, this research verifies the capability of CSCAT in monitoring polar sea ice using a machine learning-aided random forest classifier. This presented work can give guidance to sea ice monitoring with radar backscatter measurements from other spaceborne scatterometers, particular for the recently launched FY-3E scatterometer (called WindRad). [ABSTRACT FROM AUTHOR]

• Underwater superoelophobicity/superhydrophilicity. • Highly effective separation for surfactant-stabilized immiscible oil/water mixture. • Robustness and durability under harsh working conditions. • Broadband light wavelengths absorption. • High light-to-thermal energy conversion rate for seawater desalination. Freshwater contamination and scarcity have progressively exacerbated the worldwide water crisis. Developing a feasible method to remediate polluted water as well as converting the abundant seawater to freshwater has become a matter of urgency. Here we demonstrate a nanofibrous poly(vinyl alcohol) based membrane (NPM) with dual functions: oil/water separation and solar water desalination. Interconnected polypyrrole (PPY) nanoparticles were decorated on the NPM as solar light absorber as well as enabling the membrane with superwettability. The underwater superoleophobic property endows the NPM with excellent anti-fouling performance and capacity to treat surfactant-stabilized industrial wastewater containing oil or various non-polar organic solvents with a separation efficiency of more than 99%. Mechanical robustness of the membrane is enhanced by mixing graphene oxide (GO) into NPM. Meanwhile, the efficient solar thermal conversion enables NPM to further desalinize the seawater under one sun solar radiation with excellent efficiency and durability with an evaporation rate of 2.87 kg m−2h−1. In the on-site desalination test, the solar vapor system demonstrated a daily solar water purification yield of 14.3 L m−2 under natural sunlight irradiation, suggesting a promising "green" application as mass manufacture seawater purification system without extra energy source. The outstanding performances of NPM for oil-in-water emulsion separation and the high-rate seawater desalination suggest its great potential for industrial applications in the future. [ABSTRACT FROM AUTHOR]

A sensitivity analysis, based on the Greenhouse-gases Monitoring Instrument (GMI) on Chinese Gaofen 5 satellite, is described considering four input parameters that affect the retrievals of the dry air column-averaged mole fraction of CO 2 (XCO 2). The analysis is based on synthetic spectra (centered around 0.765 and 1.575 μ m) produced by SCIATRAN. The input parameters considered include the profiles of temperature and pressure, as well as the surface albedo and aerosols. The main findings are temperature errors of 1 K and pressure errors of 2 hPa lead to XCO 2 retrieval errors of less than 0.25%. The uncertainties in albedo (ranging from 0.03 to 1.0) or surface types lead to less than 2.0% retrieval error. Considering three aerosol types (urban, rural and maritime), we investigated the retrieval errors in XCO 2 that were induced by incorrect assumptions on the aerosol optical thickness (AOT). For AOT values ranging from 0.02 to 1.0, the retrieval errors are less than 6.0% if aerosols are completely neglected in the retrieval. The presented results provide a basis for rational utilization of the a priori database and are conducive to increasing the inversion accuracy. [ABSTRACT FROM AUTHOR]

This study examined seasonal bias of ammonia (NH 3) emission inventory over North China Plain (NCP) using the GEOS-Chem chemical transport model (NH 3 -standard simulation, SG1), and found that the MIX NH 3 inventory overestimates winter NH 3 by 31% and underestimates summer NH 3 by 50%. NH 3 emission from NCP is thus cut by 24% in winter and doubled in summer (NH 3 -corrected simulation, SG2) to match up with the observations. The corrected NH 3 emission changes the surface PM 2.5 and nitrate concentrations and is expected to impact the nitrogen oxides (NO x) emission control efficiency (relative changes of PM 2.5 and nitrate concentration in response to 1% NO x emission change, β PM and β NO3). We then conducted sensitivity studies (SG3) by reducing 20% (S31) and 40% (S32) NO x emission based on NH 3 -standard and NH 3 -corrected simulation, respectively. Through comparing the NO x emission control efficiency under the two NH 3 emission conditions (NH 3 -standard and NH 3 -corrected), we find that NH 3 emission bias under the NH 3 -standard condition causes ~30% overprediction of winter β PM and ~35% underprediction of summer β PM. In addition, for the NH 3 -corrected simulation, β PM increases by 43% in winter and 7.7% in summer from S31 to S32. Taken together, these findings highlighted the importance of stringent NO x emission control throughout the year and NH 3 emission control in summer as well. Moreover, it is critical to obtain a more accurate seasonal pattern of NH 3 emission inventory in assessing emission control efficiency of PM 2.5 precursors. Image 1 • Surface and satellite NH 3 observations were used to validate model in North China Plain. • Current MIX NH 3 inventory has bias of 31% and −50% in winter and summer, respectively. • Winter NO x emission control efficiency increases by 43% as cut of NO x doubles. • NH 3 emission bias leads to β PM bias of +30% in winter and −35% in summer. • Refined NH 3 emission seasonality and stricter NO X emission control are recommended. [ABSTRACT FROM AUTHOR]

Aim: To investigate the association of floor area ratio (FAR), an indicator of built environments, and myopia onset., Methods: This prospective cohort study recruited 136 753 children aged 6-10 years from 108 schools in Shenzhen, China at baseline (2016-2017). Refractive power was measured with non-cycloplegic autorefraction over a 2-year follow-up period. FAR was objectively evaluated using geographical information system technology. Mixed-effects logistic regression models were constructed to examine the association of FAR with a 2-year cumulative incidence of myopia among individuals without baseline myopia; multiple linear regression model, with a 2-year cumulative incidence rate of myopia at each school., Results: Of 101 624 non-myopic children (56.3% boys; mean (SE) age, 7.657±1.182 years) included in the study, 26 391 (26.0%) of them developed myopia after 2 years. In the individual-level analysis adjusting for demographic, socioeconomic and greenness factors, an IQR in FAR was associated with a decreased risk of 2-year myopia incidence (OR 0.898, 95% CI 0.866 to 0.932, p<0.001). Similar findings were observed in the analysis additionally adjusted for genetic and behavioural factors (OR 0.821, 95% CI 0.766 to 0.880, p<0.001). In the school-level, an IQR increase in FAR was found to be associated with a 2.0% reduction in the 2-year incidence rate of myopia (95% CI 1.3% to 2.6%, p<0.001)., Conclusions: Exposure to higher FAR was associated with a decreased myopia incidence, providing insights into myopia prevention through school built environments in China., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Conductive cardiac patches can rebuild the electroactive microenvironment for the infarcted myocardium but their repair effects benefit by carried seed cells or drugs. The key to success is the effective integration of electrical stimulation with the microenvironment created by conductive cardiac patches. Besides, due to the concerns in a high re-admission ratio of heart patients, a remote medicine device will underpin the successful repair. Herein, we report a miniature self-powered biomimetic trinity triboelectric nanogenerator with a unique double-spacer structure that unifies energy harvesting, therapeutics, and diagnosis in one cardiac patch. Trinity triboelectric nanogenerator conductive cardiac patches improve the electroactivity of the infarcted heart and can also wirelessly monitor electrocardiosignal to a mobile device for diagnosis. RNA sequencing analysis from rat hearts reveals that this trinity cardiac patches mainly regulates cardiac muscle contraction-, energy metabolism-, and vascular regulation-related mRNA expressions in vivo. The research is spawning a device that truly integrates an electrical stimulation of a functional heart patch and self-powered e-care remote diagnostic sensor., (© 2024. The Author(s).)

Adenosine (Ado) drives immune suppression in the tumor microenvironment. In this issue of Cancer Cell, Klysz et al. investigate Ado-mediated immunosuppression. Overexpression of Ado deaminase (ADA-OE), metabolizing Ado to inosine (INO), induces stemness and improves CAR T cell functionality. Likewise, exposure to INO enhances CAR T cells' function and induces stemness features., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Importance: China has experienced both rapid urbanization and major increases in myopia prevalence. Previous studies suggest that green space exposure reduces the risk of myopia, but the association between myopia risk and specific geometry and distribution characteristics of green space has yet to be explored. These must be understood to craft effective interventions to reduce myopia., Objective: To evaluate the associations between myopia and specific green space morphology using novel quantitative data from high-resolution satellite imaging., Design, Setting, and Participants: This prospective cohort study included students grades 1 to 4 (aged 6 to 9 years) in Shenzhen, China. Baseline data were collected in 2016-2017, and students were followed up in 2018-2019. Data were analyzed from September 2020 to January 2022., Exposures: Eight landscape metrics were calculated using land cover data from high-resolution Gaofen-2 satellite images to measure area, aggregation, and shape of green space., Main Outcome and Measures: The 2-year cumulative change in myopia prevalence at each school and incidence of myopia at the student level after 2 years were calculated as main outcomes. The associations between landscape metrics and school myopia were assessed, controlling for geographical, demographic, and socioeconomic factors. Principal component analyses were performed to further assess the joint effect of landscape metrics at the school and individual level., Results: A total of 138 735 students were assessed at baseline. Higher proportion, aggregation, and better connectivity of green space were correlated with slower increases in myopia prevalence. In the principal component regression, a 1-unit increase in the myopia-related green space morphology index (the first principal component) was negatively associated with a 1.7% (95% CI, -2.7 to -0.6) decrease in myopia prevalence change at the school level (P = .002). At the individual level, a 1-unit increase in myopia-related green space morphology index was associated with a 9.8% (95% CI, 4.1 to 15.1) reduction in the risk of incident myopia (P < .001), and the association remained after further adjustment for outdoor time, screen time, reading time, and parental myopia (adjusted odds ratio, 0.88; 95% CI, 0.80 to 0.97; P = .009)., Conclusions and Relevance: Structure of green space was associated with a decreased relative risk of myopia, which may provide guidance for construction and renovation of schools. Since risk estimates only indicate correlations rather than causation, further interventional studies are needed to assess the effect on school myopia of urban planning and environmental designs, especially size and aggregation metrics of green space, on school myopia.

CD8+ exhausted T cells (Tex) are heterogeneous. PD-1 inhibitors reinvigorate progenitor Tex, which subsequently differentiate into irresponsive terminal Tex. The ability to maintain a capacity for durable proliferation of progenitor Tex is important, but the mechanism remains unclear. Here, we showed CD8+ progenitor Tex pretreated with decitabine, a low-dose DNA demethylating agent, had enhanced proliferation and effector function against tumors after anti-PD-1 treatment in vitro. Treatment with decitabine plus anti-PD-1 promoted the activation and expansion of tumor-infiltrated CD8+ progenitor Tex and efficiently suppressed tumor growth in multiple tumor models. Transcriptional and epigenetic profiling of tumor-infiltrated T cells demonstrated that the combination of decitabine plus anti-PD-1 markedly elevated the clonal expansion and cytolytic activity of progenitor Tex compared with anti-PD-1 monotherapy and restrained CD8+ T cell terminal differentiation. Strikingly, decitabine plus anti-PD-1 sustained the expression and activity of the AP-1 transcription factor JunD, which was reduced following PD-1 blockade therapy. Downregulation of JunD repressed T cell proliferation, and activation of JNK/AP-1 signaling in CD8+ T cells enhanced the antitumor capacity of PD-1 inhibitors. Together, epigenetic agents remodel CD8+ progenitor Tex populations and improve responsiveness to anti-PD-1 therapy.

CO 2 column-weighted dry-air mixing ratio (X CO2 ) products with high precision and spatial resolution are essential for inverting CO 2 fluxes and promoting our understanding of global climate change. Compared with passive remote sensing methods, IPDA LIDAR, as an active remote sensing technique, offers many advantages in measuring X CO2 . However, a significant random error in IPDA LIDAR measurements causes X CO2 values calculated directly from LIDAR signals to be unqualified as the final X CO2 products. Hence, we propose an efficient particle filter-based inversion of CO 2 for single observation (EPICSO) algorithm to precisely retrieve the X CO2 of every LIDAR observation while preserving the high spatial resolution of LIDAR measurements. The EPICSO algorithm adopts the sliding average results as the first estimate of the local X CO2 ; subsequently, it estimates the difference between two adjacent X CO2 points and calculates the posterior probability of X CO2 based on particle filter theory. To evaluate the performance of the EPICSO algorithm numerically, we perform an EPICSO to process pseudo-observation data. The simulation results show that the results retrieved by the EPICSO algorithm satisfy the required high precision and that the algorithm is robust to a significant amount of random errors. In addition, we utilize LIDAR observation data from actual experiments in Hebei, China, to validate the performance of the EPICSO algorithm. The results retrieved by the EPICSO algorithm are more consistent with the actual local X CO2 than those of the conventional method, indicating that the EPICSO algorithm is efficient and practical for retrieving X CO2 with high precision and spatial resolution.

Land carbon sink is a vital component for the achievement of China's ambitious carbon neutrality goal, but its magnitude is poorly known. Atmospheric observations and inverse models are valuable tools to constrain the China's land carbon sink. Space-based CO 2 measurements from satellites form an emerging data stream for application of such atmospheric inversions. Here, we reviewed the satellite missions that is dedicated to the monitoring of CO 2 , and the recent progresses on the inversion of China's land carbon sink using satellite CO 2 measurements. We summarized the limitations and challenges in current space platforms, retrieval algorithms, and the inverse modeling. It is shown that there are large uncertainties of contemporary satellite-based estimates of China's land carbon sink. We discussed future opportunities of continuous improvements in three aspects to better constrain China's land carbon sink with space-based CO 2 measurements., (© 2022 John Wiley & Sons Ltd.)

Chimeric antigen receptor (CAR) T cell therapy has limited efficacy against solid tumors, and one major challenge is T cell exhaustion. To address this challenge, we performed a candidate gene screen using a hypofunction CAR-T cell model and found that depletion of basic leucine zipper ATF-like transcription factor (BATF) improved the antitumor performance of CAR-T cells. In different types of CAR-T cells and mouse OT-1 cells, loss of BATF endows T cells with improved resistance to exhaustion and superior tumor eradication efficacy. Mechanistically, we found that BATF binds to and up-regulates a subset of exhaustion-related genes in human CAR-T cells. BATF regulates the expression of genes involved in development of effector and memory T cells, and knocking out BATF shifts the population toward a more central memory subset. We demonstrate that BATF is a key factor limiting CAR-T cell function and that its depletion enhances the antitumor activity of CAR-T cells against solid tumors., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Bioadhesives act as a bridge in wound closure by forming an effective interface to protect against liquid and gas leakage and aid the stoppage of bleeding. To their credit, tissue adhesives have made an indelible impact on almost all wound-related surgeries. Their unique properties include minimal damage to tissues, low chance of infection, ease of use and short wound-closure time. In contrast, classic closures, like suturing and stapling, exhibit potential additional complications with long operation times and undesirable inflammatory responses. Although tremendous progress has been made in the development of tissue adhesives, they are not yet ideal. Therefore, highlighting and summarizing existing adhesive designs and synthesis, and comparing the different products will contribute to future development. This review first provides a summary of current commercial traditional tissue adhesives. Then, based on adhesion interaction mechanisms, the tissue adhesives are categorized into three main types: adhesive patches that bind molecularly with tissue, tissue-stitching adhesives based on pre-polymer or precursor solutions, and bioinspired or biomimetic tissue adhesives. Their specific adhesion mechanisms, properties and related applications are discussed. The adhesion mechanisms of commercial traditional adhesives as well as their limitations and shortcomings are also reviewed. Finally, we also discuss the future perspectives of tissue adhesives., (© The Author(s) 2022. Published by Oxford University Press.)

Until now, there has been a lack of standard and effective treatments for patients with recurrent malignant tumors or abdominal and pelvic malignancies with extensive invasion (Morris, 2000). Generally, these patients face problems such as inability to undergo surgery or chemotherapy resistance (Combs et al., 2016). Re-radiotherapy has achieved a prominent place in the treatment of patients who have received radiotherapy previously and developed in-field recurrences (Straube et al., 2018). However, re-radiotherapy is very complicated, requiring comprehensive consideration of appropriate radiation dose, interval from first radiotherapy, boundary of the radiotherapy target area, and damage to surrounding normal tissues (Straube et al., 2019). In other words, it is necessary to focus on the protection of surrounding normal tissues while maximizing the efficacy of re-radiotherapy in such patients.

Programmed cell death protein-1 (PD-1)-mediated immunosuppression has been proposed to contribute to the limited clinical efficacy of chimeric antigen receptor T (CAR-T) cells in solid tumors. We generated PD-1 and T cell receptor (TCR) deficient mesothelin-specific CAR-T (MPTK-CAR-T) cells using CRISPR-Cas9 technology and evaluated them in a dose-escalation study. A total of 15 patients received one or more infusions of MPTK-CAR-T cells without prior lymphodepletion. No dose-limiting toxicity or unexpected adverse events were observed in any of the 15 patients. The best overall response was stable disease (2/15 patients). Circulating MPTK-CAR-T cells peaked at days 7-14 and became undetectable beyond 1 month. TCR-positive CAR-T cells rather than TCR-negative CAR-T cells were predominantly detected in effusion or peripheral blood from three patients after infusion. We further confirmed the reduced persistence of TCR-deficient CAR-T cells in animal models. Our results establish the preliminary feasibility and safety of CRISPR-engineered CAR-T cells with PD-1 disruption and suggest that the natural TCR plays an important role in the persistence of CAR-T cells when treating solid tumors., (© 2021. The Author(s).)

Silver nanowires (i.e., AgNWs) can act as effective surface-enhanced Raman spectroscopy (i.e., SERS) substrates to detect small molecules. However, a lot of prepared AgNWs were often wrapped by polyvinylpyrrolidone (i.e., PVP) thin film to form an insulating layer to produce ill-defined AgNWs-PVP-AgNWs interface, limiting the plasmonic coupling among the stacked AgNWs. Herein, we reported a facile method in removal of PVP ligands from AgNWs for high performance and reusable SERS substrate. Sodium borohydride (NaBH 4 ) was used to completely remove the PVP ligands from the surface of AgNWs and produce a clean AgNWs-AgNWs interface that effectively enhances the localized surface plasmon resonance (i.e., LSPR) was produced, greatly improving the SERS activity of the AgNWs thin film. The SERS detection of rhodamine 6G (i.e., R6G) used with PVP AgNWs and without PVP AgNWs is 1.0 × 10 -9 and 1.0 × 10 -15  M, and the average enhancement factor (EF) is about 0.86 × 10 4 and 9.35 × 10 4 , respectively. Moreover, the recyclable behavior of the AgNWs with several analyte molecules is much more interesting than that of the PVP@AgNWs. The SERS detection of AgNWs for R6G, the 3-mercaptopropionic acid (i.e., 3-MPA) and melamine with good recyclability in nanomolar and millimolar concentration can be easily detected., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Recent advances in the development of gene editing technologies, especially the CRISPR/Cas 9 system, have substantially enhanced our ability to make precise and efficient changes in the genomes of various cells. In particular, the genetic engineering of T cells holds huge potential to improve the efficacy and safety of T cells-based cancer therapy. Due to its ease of use and high efficiency, CRISPR/Cas9 enables efficient gene knockout, site-specific knock-in, and genome-wide screen in T cells. Here we review the current progress of applying gene editing to T-cell therapy, focusing on the technical aspects of the CRISPR/Cas9 platform. We also discuss the challenges and future prospects.

3D printing, an additive manufacturing based technology for precise 3D construction, is currently widely employed to enhance applicability and function of cell laden scaffolds. Research on novel compatible biomaterials for bioprinting exhibiting fast crosslinking properties is an essential prerequisite toward advancing 3D printing applications in tissue engineering. Printability to improve fabrication process and cell encapsulation are two of the main factors to be considered in development of 3D bioprinting. Other important factors include but are not limited to printing fidelity, stability, crosslinking time, biocompatibility, cell encapsulation and proliferation, shear-thinning properties, and mechanical properties such as mechanical strength and elasticity. In this review, we recite recent promising advances in bioink development as well as bioprinting methods. Also, an effort has been made to include studies with diverse types of crosslinking methods such as photo, chemical and ultraviolet (UV). We also propose the challenges and future outlook of 3D bioprinting application in medical sciences and discuss the high performance bioinks.

T cells engineered with chimeric antigen receptor (CAR) have been successfully applied to treat advanced refractory B cell malignancy. However, many challenges remain in extending its application toward the treatment of solid tumors. The immunosuppressive nature of tumor microenvironment is considered one of the key factors limiting CAR-T efficacy. One negative regulator of Tcell activity is lymphocyte activation gene-3 (LAG-3). We successfully generated LAG-3 knockout Tand CAR-T cells with high efficiency using CRISPR-Cas9 mediated gene editing and found that the viability and immune phenotype were not dramatically changed during in vitro culture. LAG-3 knockout CAR-T cells displayed robust antigen-specific antitumor activity in cell culture and in murine xenograft model, which is comparable to standard CAR-T cells. Our study demonstrates an efficient approach to silence immune checkpoint in CAR-T cells via gene editing.