Gradual effects of gradient concentrations of perfluorooctane sulfonate on the antioxidant ability and gut microbiota of red claw crayfish (Cherax quadricarinatus).

Perfluorooctane sulfonate (PFOS) is a typical persistent organic pollutant that is characterized by environmental persistence, bioaccumulation, and toxicity. In this study, we investigated the gut microbial response of the red claw crayfish Cherax quadricarinatus after 28 days of exposure to 0 ng/L, 1 ng/L, 10 µg/L, or 10 mg/L of PFOS as a stressor. We measured oxidative stress-related enzyme activities and expression of molecules related to detoxification mechanisms to evaluate the toxic effects of PFOS. We found that PFOS disturbed microbial homeostasis in the gut of C. quadricarinatus, resulting in increased abundance of the pathogen Shewanella and decreased abundance of the beneficial bacterium Lactobacillus. The latter especially disturbed amino acid transport and carbohydrate transport. We also found that the activities of glutathione S-transferase and glutathione peroxidase were positively correlated with the expression levels of cytochrome P450 genes (GST1-1, GSTP, GSTK1, HPGDS, UGT5), which are products of PFOS-induced oxidative stress and play an antioxidant role in the body. The results of this study provided valuable ecotoxicological data to better understand the biological fate and effects of PFOS in C. quadricarinatus.

Occurrence and Risk Assessment of Pesticides, Phthalates, and Heavy Metal Residues in Vegetables from Hydroponic and Conventional Cultivation.

Hydroponic cultivation of fresh produce is gaining popularity worldwide, but few studies have provided a comparative assessment of hydroponic and conventional soil-based vegetables. In this study, we analyzed a series of hazardous chemicals, including 120 pesticides, 18 phthalates (PAEs), and 2 heavy metals (lead and cadmium) in four vegetable commodities (lettuces, celeries, tomatoes, and cucumbers) from hydroponic and conventional soil-based cultivation. Our study showed that at least one pesticide was present in 84% of the conventionally grown samples, whereas only 30% of the hydroponic samples contained detectable pesticide residues. Regarding the total PAE concentrations, there was no significant difference between conventional and hydroponic vegetables. The lead and cadmium residues in conventionally cultivated vegetables were significantly higher than in those produced from hydroponic cultivation. Lead is the primary heavy metal pollutant across all vegetable samples. The hazard index (HI) values of the hydroponic and conventional vegetables were 0.22 and 0.64, respectively. Since both values are below one, the exposure to these hazardous chemicals through consumption of the studied vegetables may not pose a significant health risk. The HI values also suggested that the health risks of eating hydroponic vegetables are lower than for conventional soil-based vegetables.

Sleep deprivation boosts O2·- levels in the brains of mice as visualized by a Golgi apparatus-targeted ratiometric fluorescence nanosensor.

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice. Golgi dots can be readily synthesized by coprecipitation of Golgi-F127, an amphiphilic polymer F127 modified with a Golgi apparatus targeting moiety, caffeic acid (CA), the responsive unit for O2·-, and red emissive carbon nanodots (CDs), which act as the reference signal. The fluorescence emission spectrum of the developed nanoprobe showed an intense peak at 674 nm, accompanied by a shoulder peak at 485 nm. As O2·- was gradually added, the fluorescence at 485 nm continuously increased; in contrast, the emission intensity at 674 nm assigned to the CDs remained constant, resulting in the ratiometric sensing of O2·-. The present ratiometric nanoprobe showed high selectivity for O2·- monitoring due to the specific recognition of O2·- by CA. Moreover, the Golgi dots exhibited good linearity with respect to the O2·- concentration within 5 to 40 µM, and the limit of detection (LOD) was ~ 0.13 µM. Additionally, the Golgi dots showed low cytotoxicity and an ability to target the Golgi apparatus. Inspired by these excellent properties, we then applied the Golgi dots to successfully monitor exogenous and endogenous O2·- levels within the Golgi apparatus. Importantly, with the help of Golgi dots, we determined that SD substantially elevated O2·- levels in the brain.

Healthier Dietary Patterns Are Associated with Better Sleep Quality among Shanghai Suburban Adults: A Cross-Sectional Study.

BACKGROUND: More is to be explored between dietary patterns and sleep quality in the Chinese adult population. METHODS: A cross-sectional study including 7987 Shanghai suburban adults aged 20-74 years was conducted. Dietary information was obtained using a validated food frequency questionnaire. Adherence to a priori dietary patterns, such as the Chinese Healthy Eating Index (CHEI), Dietary Approaches to Stop Hypertension (DASH) diet and Mediterranean diet (MD), was assessed. Sleep quality was assessed from self-reported responses to the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Logistic regression models adjusting for confounders were employed to examine the associations. RESULTS: The overall prevalence of poor sleep (PSQI score ≥ 5) was 28.46%. Factor analysis demonstrated four a posteriori dietary patterns. Participants with a higher CHEI (ORQ4 vs. Q1: 0.81, 95% CI: 0.70-0.95), DASH (ORQ4 vs. Q1: 0.70, 95% CI: 0.60-0.82) or MD (ORQ4 vs. Q1: 0.75, 95% CI: 0.64-0.87) had a lower poor sleep prevalence, while participants with a higher "Beverages" score had a higher poor sleep prevalence (ORQ4 vs. Q1: 1.18, 95% CI: 1.02-1.27). CONCLUSIONS: In Shanghai suburban adults, healthier dietary patterns and lower consumption of beverages were associated with better sleep quality.

Evaluating imaging repeatability of fully self-service fundus photography within a community-based eye disease screening setting.

PURPOSE: This study aimed to investigate the imaging repeatability of self-service fundus photography compared to traditional fundus photography performed by experienced operators. DESIGN: Prospective cross-sectional study. METHODS: In a community-based eye diseases screening site, we recruited 65 eyes (65 participants) from the resident population of Shanghai, China. All participants were devoid of cataract or any other conditions that could potentially compromise the quality of fundus imaging. Participants were categorized into fully self-service fundus photography or traditional fundus photography group. Image quantitative analysis software was used to extract clinically relevant indicators from the fundus images. Finally, a statistical analysis was performed to depict the imaging repeatability of fully self-service fundus photography. RESULTS: There was no statistical difference in the absolute differences, or the extents of variation of the indicators between the two groups. The extents of variation of all the measurement indicators, with the exception of the optic cup area, were below 10% in both groups. The Bland-Altman plots and multivariate analysis results were consistent with results mentioned above. CONCLUSIONS: The image repeatability of fully self-service fundus photography is comparable to that of traditional fundus photography performed by professionals, demonstrating promise in large-scale eye disease screening programs.

Alveolar bone loss and tooth loss contribute to increase in cancer mortality among older patients.

BACKGROUND: Both cancer and periodontitis are more prevalent with age. Information on their relationship in older patients is limited. This study aims to examine whether periodontitis is associated with increased risk of cancer mortality with a ≥ 75-year age group cohort. METHODS: A retrospective cohort study was conducted on 1146 patients who had digital radiographic examinations. Alveolar bone loss and loss of teeth were measured as indicators of periodontitis. Hazard ratio (HR) with 95% confidence interval (CI) were taken as the effect size to summarize the associations between periodontitis and risks of cancer mortality using the multivariate adjusted cox proportional hazards model and competing risk hazard model. RESULTS: Totally, 104 total cancer, 28 lip, oral cavity and pharynx (LOP) cancer, 39 digestive cancer and 13 respiratory cancer cases were documented over 10 years of follow-up. Total cancer (HR 1.27, 95% CI 1.06-1.53) displayed statistically significant associations with alveolar bone loss and tooth loss after adjusting for relevant confounding variables. We also observed borderline significant association between alveolar bone loss and LOP cancer (HR 1.45, 95% CI 0.99-2.12). The above associations were consistent with the results observed from the competing risk hazard models. CONCLUSION: Our results indicate that older patients suffering from tooth loss or alveolar bone loss are at increased risks of cancer mortality, especially for total cancer and LOP cancer.

Polystyrene nanospheres-induced hepatotoxicity in swamp eel (Monopterus albus): From biochemical, pathological and transcriptomic perspectives.

As ubiquitous emerging pollutants, microplastics (MPs) in aquatic environments have aroused critical global concerns. Despite the occurrence and characteristics of MPs in freshwater agroecosystems well-described by our previous study, their ecotoxicological implications in Monopterus albus remains unfathomed. Herein, we dissected toxic effects and mechanisms of PS-NPs exposure against M. albus hepatic tissues at concentrations of 0.5 (L), 5 (M), 10 (H) mg/L for 28 days using physiochemical measurements, histopathological analysis and transcriptomic sequencing. Results showed that upon PS-NPs treatments, levels of ROS, MDA, 8-OHdG and MFO activity were significantly enhanced relative to the control (C) group, while SP content and T-AOC activity were dramatically suppressed, suggesting ROS burst, lipid peroxidation and DNA damage may occur in liver tissues. This oxidative damage further triggered impaired hepatic function and histopathology, disordered lipid metabolism and hepatocyte apoptosis, as reflected by significantly diminished activities of GPT, GOT, ACP, AKP and LDH, paralleled with augmented levels of TG, TC and HSI as well as Cytc and Caspase-3,8,9 activities. Noticeably, concentration-dependent rises of apoptotic rate, vacuolar degeneration and lipid deposition were manifest in TUNEL, H&E and ORO staining. In addition, a total of 375/475/981 up-regulated as well as 260/611/1422 down-regulated DEGs in C vs L, C vs M and C vs H categories were identified based on RNA-seq, respectively. These DEGs were significantly annotated and enriched into GO terms (membrane, cytoplasm, response to stimuli, oxidation-reduction process) as well as KEGG pathways (ether lipid metabolism, apoptosis, chemical carcinogenesis-reactive oxygen species, non-alcoholic fatty liver disease). Moreover, signaling cascades Keap1-Nrf2, p53 and PPAR were either substantially initiated or dysregulated to orchestrate PS-NPs hepatotoxicity featuring oxidative damage, hepatocyte apoptosis and lipid steatosis. Collectively, this study not only expounded on toxicological mechanisms whereby PS-MPs exerted deleterious effects on M. albus, but also pointed to ecological risks of PS-MPs-induced hepatoxicity and lipid steatosis in this commercially-important species.

Deep-learning-based ring artifact correction for tomographic reconstruction.

X-ray tomography has been widely used in various research fields thanks to its capability of observing 3D structures with high resolution non-destructively. However, due to the nonlinearity and inconsistency of detector pixels, ring artifacts usually appear in tomographic reconstruction, which may compromise image quality and cause nonuniform bias. This study proposes a new ring artifact correction method based on the residual neural network (ResNet) for X-ray tomography. The artifact correction network uses complementary information of each wavelet coefficient and a residual mechanism of the residual block to obtain high-precision artifacts through low operation costs. In addition, a regularization term is used to accurately extract stripe artifacts in sinograms, so that the network can better preserve image details while accurately separating artifacts. When applied to simulation and experimental data, the proposed method shows a good suppression of ring artifacts. To solve the problem of insufficient training data, ResNet is trained through the transfer learning strategy, which brings advantages of robustness, versatility and low computing cost.

Stable isotope and elemental profiles determine geographical origin of saffron from China and Iran.

Origin verification of high-value saffron is essential for fair trade and to protect consumers' interests and rights. A traceability method using elemental content (% C and % N) and stable isotopes (δ13C, δ2H, δ18O, and δ15N) combined with chemometrics was developed to discriminate saffron from Iran and China and classify major domestic production areas in China. Results showed that Iranian samples had lower % C and % N contents but higher δ13C values than Chinese origin saffron, with δ13C acting as an important variable for origin discrimination. Moreover, δ2H and δ13C isotopes were found to be important variables to classify Chinese regional saffron origin. Two supervised pattern recognition models (PLS-DA) developed to classify Iranian and Chinese saffron, and regional Chinese saffron had a discrimination accuracy of 85.0 % and 80.2 %, respectively. These models provide the basis for a new regulatory inspection procedure to verify saffron origin and label claims, minimizing fraudulent mislabeling and adding value to saffron from specific regions.

Feature detection network-based correction method for accurate nano-tomography reconstruction.

Driven by the development of advanced x-ray optics such as Fresnel zone plates, nano-resolution full-field transmission x-ray microscopy (Nano-CT) has become a powerful technique for the non-destructive volumetric inspection of objects and has long been developed at different synchrotron radiation facilities. However, Nano-CT data are often associated with random sample jitter because of the drift or radial/axial error motion of the rotation stage during measurement. Without a proper sample jitter correction process prior to reconstruction, the use of Nano-CT in providing accurate 3D structure information for samples is almost impossible. In this paper, to realize accurate 3D reconstruction for Nano-CT, a correction method based on a feature detection neural network, which can automatically extract target features from a projective image and precisely correct sample jitter errors, is proposed, thereby resulting in high-quality nanoscale 3D reconstruction. Compared with other feature detection methods, even if the target feature is overlapped by other high-density materials or impurities, the proposed Nano-CT correction method still acquires sub-pixel accuracy in geometrical correction and is more suitable for Nano-CT reconstruction because of its universal and faster correction speed. The simulated and experimental datasets demonstrated the reliability and validity of the proposed Nano-CT correction method.

Toxic effects and transcriptional responses in zebrafish liver cells following perfluorooctanoic acid exposure.

As a typical type of persistent organic pollutant, perfluorooctanoic acid (PFOA) is pervasive in the environment. Multiple studies have found that PFOA has hepatotoxicity, but the mechanism remains poorly understood. In this study, the toxic effects of different concentrations of PFOA on zebrafish liver cells were systematically assessed by recording cell survival, ultrastructural observations, and transcriptome analyses. The results showed that the inhibition of cell viability and the massive accumulation of autophagic vacuoles were observed at 400 µM PFOA, while transcriptomic changes occurred with treatments of 1 and 400 µM PFOA. The transcription levels of 1055 (977 up- and 78 down-regulated genes) and 520 (446 up- and 74 down-regulated genes) genes were significantly changed after treatment with 1 and 400 µM PFOA, respectively. Based on Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis, significant expression changes were observed in autophagy, tight junction, signal transduction, immune system, endocrine system, and metabolism-related pathways, indicating that such processes were greatly affected by PFOA exposure. The findings of this study will provide a scientific basis for the toxic effects and potential toxic mechanisms of PFOA on zebrafish, and provide information for ecological risk assessments.

A GRIP-1-EZH2 switch binding to GATA-4 is linked to the genesis of rhabdomyosarcoma through miR-29a.

Terminal differentiation failure is an important cause of rhabdomyosarcoma genesis, however, little is known about the epigenetic regulation of aberrant myogenic differentiation. Here, we show that GATA-4 recruits polycomb group proteins such as EZH2 to negatively regulate miR-29a in undifferentiated C2C12 myoblast cells, whereas recruitment of GRIP-1 to GATA-4 proteins displaces EZH2, resulting in the activation of miR-29a during myogenic differentiation of C2C12 cells. Moreover, in poorly differentiated rhabdomyosarcoma cells, EZH2 still binds to the miR-29a promoter with GATA-4 to mediate transcriptional repression of miR-29a. Interestingly, once re-differentiation of rhabdomyosarcoma cells toward skeletal muscle, EZH2 was dispelled from miR-29a promoter which is similar to that in myogenic differentiation of C2C12 cells. Eventually, this expression of miR-29a results in limited rhabdomyosarcoma cell proliferation and promotes myogenic differentiation. We thus establish that GATA-4 can function as a molecular switch in the up- and downregulation of miR-29a expression. We also demonstrate that GATA-4 acts as a tumor suppressor in rhabdomyosarcoma partly via miR-29a, which thus provides a potential therapeutic target for rhabdomyosarcoma.

Determining the geographical origin and cultivation methods of Shanghai special rice using NIR and IRMS.

Songjiang CPB rice (cultivated by a 'combination of planting and breeding') and Chongming NCFP rice (cultivated by using 'no chemical fertilizers and pesticides') are two high quality special rice products developed for Shanghai urban agriculture. Protecting these products from geographical origin mislabeling or cultivation method fraud are very important. To verify the origin of Songjiang and Chongming rice and discriminate their cultivation methods (CPB or N (non) CPB, NCFP or chemical fertilizers and pesticides (CFP)), NIR and IRMS methods combined with chemometrics were developed. Results showed complete separation of Songjiang and Chongming rice from other geographic origins using NIR combined with PLSDA and LVQNN; CPB and NCPB Songjiang rice could be completely identified using NIR or IRMS, while the optimal identification accuracy rate of NCFP from CFP in Chongming rice was 87.5%. It provided a rapid and robust method to identify the origin and cultivation methods of Shanghai special rice.

New insights into the transfer and accumulation of dioxins and dioxin-like PCBs in the food web of farmed Chinese mitten crabs: A typical case from the Yangtze River area.

Dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) transfer and accumulation behavior remains poorly understood in the farmed Chinese mitten crab (Eriocheir sinensis). In this study, dioxins and DL-PCBs concentration in 48 farming crabs in lower reaches of the Yangtze River was monitored and controlled field design was conducted in a typical farm to dissect the dioxins and DL-PCBs contamination in crab food web (crab, feeds, and environment). Results showed that dioxins and DL-PCBs were ubiquitous in farmed crabs with concentrations ranging from 0.390 to 37.2 pg toxic equivalents (TEQ) g-1 ww and do not present a health risk to general consumers. Of the total dioxins TEQ found in crab in treated farms, 45.6% was attributed to direct transfer from the aquaculture environment and 46.5% to the consumption of snails. Consumption of feed material accounted for nearly all of the total DL-PCBs TEQ, divided as 58.2% from feed and 41.8% from snails. These results demonstrated that dominant routes of dioxins accumulation in crabs were transferred for the sediment-snail-crab and sediment-crab chains, whereas DL-PCBs is mainly transferred through consumption of feeds and snails. To our knowledge, this work is the first report of snails serving as a biomagnification medium that promotes accumulation of dioxins in mitten crabs. This observation provided crucial insight to prevent and reduce contamination of crab by dioxins and DL-PCBs.

Effects of Application of Pig Manure on the Accumulation of Heavy Metals in Rice.

Pig manure (PM) is often highly enriched in heavy metals, such as Cu and Zn, due to the wide use of feed additives. To study the potential risks of heavy metal accumulation in the soil and rice grains by the application of PM and other organic manure, a four-year field experiment was conducted in the suburb of Shanghai, southeast China. The contents of Cu, Zn, Pb, and Cd in the soils and rice plants by the treatments of PM and fungal culturing residues (FCR) show a trend of annual increase. Those in the soils and rice by the PM treatment are raised even more significantly. Cu and Zn contents in the soil and rice roots by the PM are significantly higher than those by the non-fertilizer control (CK) during the four years, and Pb and Cd also significantly higher than CK in the latter two years. Heavy metals taken up by the rice plants are mostly retained in the roots. Cu and Zn contents in the rice plants are in the decreasing order of roots > grains > stems > leaves, and Pb and Cd in the order of roots > stems > leaves > grains. Cu, Zn, Pb, and Cd contents in the soils by the PM treatment increase by 73%, 32%, 106%, and 127% on annual average, and those in the brown rice by 104%, 98%, 275%, and 199%, respectively. The contents of Cu, Zn, Pb, and Cd in the brown rice of the treatments are significantly correlated with those in the soils and rice roots (p < 0.05), suggesting the heavy metals accumulated in the rice grains come from the application of PM and FCR. Though the contents of heavy metals in the brown rice during the four experimental years are still within the safe levels, the risks of their accumulative increments, especially by long-term application of PM, can never be neglected.

How to Conduct School Myopia Screening: Comparison Among Myopia Screening Tests and Determination of Associated Cutoffs.

PURPOSE: To compare the accuracy for various screening tests and their combined uses for myopia screening among children and adolescents and explore age-specific cutoffs. DESIGN: Cross-sectional study. METHODS: A total of 6017 children and adolescents aged 4 to 15 years participated in the study. Uncorrected visual acuity (UCVA, recorded in decimal notation), cycloplegic and noncycloplegic refraction (NCR), axial length (AL), and corneal curvature radius (CR) examinations were performed. Cycloplegic spherical equivalent ≤-0.50 D was considered as the gold standard for myopia. Receiver operating characteristic (ROC) curves were drawn to determine optimal cutoffs for all age groups, and sensitivity, specificity, as well as screening prevalence of myopia were calculated. RESULTS: The overall estimate of myopia prevalence was 31.8% using the gold standard. The sensitivity and specificity of the UCVA alone for the commonly used cutoff (1.0) were 97.7% and 33.1%, respectively. The areas under the ROC curve were optimally estimated to be 0.985 (95% CI, 0.982-0.988) for the combined use of UCVA and NCR tests, and 0.987 (95% CI, 0.983-0.989) for the combined use of AL/CR and NCR tests, with no significant difference (P = 0.208). The best cutoffs for UCVA-NCR combinations were UCVA <1.0 and NCR <-0.25 D in 4 to 6 years; UCVA <1.0 and NCR <-0.50 D in 7 to 12 years; UCVA <0.8 and NCR <-0.75 D in 13 to 15 years. If those screening positive were all referred to clinics and corrected with cycloplegic autorefraction data, the relative difference between screening prevalence and the actual prevalence by the gold standard would reduce from 13.2% to 4.7%. CONCLUSIONS: UCVA test alone for detecting myopia demonstrated a poorer accuracy among these tests. The combined use of UCVA and NCR tests and the combined use of AL/CR and NCR tests achieved optimal accuracy for myopia screening. Setting age-specific cutoffs would increase the accuracy, and the prevalence obtained from primary screening should be corrected according to the data of cycloplegic refraction after referral, especially in younger ages.

Deep-learning-based image registration for nano-resolution tomographic reconstruction.

Nano-resolution full-field transmission X-ray microscopy has been successfully applied to a wide range of research fields thanks to its capability of non-destructively reconstructing the 3D structure with high resolution. Due to constraints in the practical implementations, the nano-tomography data is often associated with a random image jitter, resulting from imperfections in the hardware setup. Without a proper image registration process prior to the reconstruction, the quality of the result will be compromised. Here a deep-learning-based image jitter correction method is presented, which registers the projective images with high efficiency and accuracy, facilitating a high-quality tomographic reconstruction. This development is demonstrated and validated using synthetic and experimental datasets. The method is effective and readily applicable to a broad range of applications. Together with this paper, the source code is published and adoptions and improvements from our colleagues in this field are welcomed.

Occurrence of Microplastics in Fish and Shrimp Feeds.

Plastics with particle sizes of 100 nm to 5 mm are known as microplastics. The contamination of seafood-based feeds by larger microplastics (20 µm to 5 mm) is a growing concern. Here, we analyzed fish and shrimp meals. Microplastics were extracted using density separation methods and characterized using scanning micro Fourier transform infrared spectroscopy (µ-FT-IR). The average microplastic abundance in shrimp meal was 10.7 microplastics·100 g-1. In fish meal, 1.02% of the microplastics were smaller than 1 mm, while most of the microplastics in shrimp meal were 1-5 mm. Eight colors of microplastics were observed; black, red, and orange microplastics have been rarely reported in previous studies. The microplastics found included films, fibers, and fragments, with film-type microplastics being the most common. The main chemical components of fiber-type microplastics were olefins and polyester, while film- and fragment-type microplastics were mainly paraffin and polyethylene. Additional in-depth studies of microplastics in feeds are necessary to provide data support for feed safety assessments.

Fast Li Plating Behavior Probed by X-ray Computed Tomography.

Uneven lithium plating/stripping is an essential issue that inhibits stable cycling of a lithium metal anode and thus hinders its practical applications. The investigation of this process is challenging because it is difficult to observe lithium in an operating device. Here, we demonstrate that the microscopic lithium plating behavior can be observed in situ in a close-to-practical cell setup using X-ray computed tomography. The results reveal the formation of porous structure and its progressive evolution in space over the charging process with a large current. The elaborated analysis indicates that the microstructure of deposited lithium makes a significant impact on the subsequent lithium plating, and the impact of structural inhomogeneity, further exaggerated by the large-current charging, can lead to severely uneven lithium plating and eventually cell failure. Therefore, a codesign strategy involving delicate controls of microstructure and electrochemical conditions could be a necessity for the next-generation battery with lithium metal anode.

Enhancing the Thermal Stability of NASICON Solid Electrolyte Pellets against Metallic Lithium by Defect Modification.

All-solid-state batteries (ASSBs) are expected to address the battery safety issues fundamentally by replacing the flammable electrolyte with solid electrolytes (SEs). However, recent studies report that the thermal runaway happened for NASICON-type SEs when they contact with Li metal at high temperature and indicate that the ASSBs may not be totally safe. Here, the thermal stability of a NASICON-type Li1.4Al0.4Ti1.6(PO4)3 (LATP) SE pellet against metallic lithium is quantified in a quasi-practical situation. Accelerated thermal runaway of the LATP pellet compared to LATP powder is observed when they contact with lithium. Combining electrochemical impedance spectroscopy and X-ray computed tomography analysis, lithium penetration into the pellet at high temperature has been observed. The penetrated lithium without surface impurities and the high reactivity of LATP at defect sites (atomic structural defects, cracks, voids, etc.) lead to higher interfacial reactivity and earlier thermal runaway. By adding LiPO2F2 to modify those defect sites of the LATP pellet and impede the lithium/SE interfacial reactions, the thermal runaway can be remarkably delayed. This work elucidates the thermal runaway behaviors of Li/LATP pellets in a quasi-practical environment, provides new information about safety issues of ASSBs, and inspires future investigations into this urgent-needed area.