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Patients with EGFR-mutated non-small cell lung cancer (NSCLC) respond poorly to immune checkpoint inhibitors (ICIs). It has been reported that the number of CD8+T cells is reduced in EGFR-mutated NSCLC. However, the extent of heterogeneity and effector function of distinct populations of CD8+T cells has not been investigated intensively. In addition, studies investigating whether a combination of radiotherapy and ICIs can improve the efficacy of ICIs in EGFR-mutated lung cancer are lacking. Single-cell RNA sequencing (scRNA-seq) was used to investigate the heterogeneity of CD8+T cell populations in EGFR-mutated NSCLC. The STING pathway was explored after hypofractionated radiation of EGFR-mutated and wild-type cells. Mice bearing LLC-19del and LLC-EGFR tumors were treated with radiotherapy plus anti-PD-L1. The scRNA-seq data showed the percentage of progenitor exhausted CD8+T cells was lower in EGFR-mutated NSCLC. In addition, CD8+T cells in EGFR-mutated NSCLC were enriched in oxidative phosphorylation. In EGFR-mutated and wild-type cells, 8 Gy × 3 increased the expression of chemokines that recruit T cells and activate the cGAS-STING pathway. In the LLC-19del and LLC-EGFR mouse model, the combination of radiation and anti-PD-L1 significantly inhibited the growth of abscopal tumors. The enhanced abscopal effect was associated with systemic CD8+T cell infiltration. This study provided an intensive understanding of the heterogeneity and effector functions of CD8+T cells in EGFR-mutated NSCLC. We showed that the combination of hypofractionated radiation and anti-PD-L1 significantly enhanced the abscopal responses in both EGFR-mutated and wild-type lung cancer by activating CD8+T cells in mice.
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OBJECTIVE: To observe the effects and mechanisms of Maresin2 on the function of DCs(Dendritic cells). METHOD: The levels of IL-6, IL-12, TNF-α and IL-1ß secreted by BMDCs (Bone marrow-derived Dendritic cells) after Maresin2 treatment were detected by ELISA. At the same time, the expressions of costimulatory molecules CD40 and CD86 on the surface, the ability of phagocytosis of ovalbumin(OVA) antigen, and antigen presentation function in BMDCs were analyzed by flow cytometry. Finally, MAPK and NF-κB pathway signaling phosphorylation in Maresin2-treated BMDCs were detected by western blot. RESULTS: The secretion levels of IL-6, IL-12, TNF-α and IL-1ß were significantly decreased in the Maresin2 treatment group after LPS treatment (P < 0.05). The expression levels of CD86 and CD40 were significantly decreased after Maresin2 treatment (P < 0.05). Maresin2 enhanced the phagocytosis ability of ovalbumin(OVA) (P < 0.05), but the ability of antigen presentation of BMDCs with the treatment of Maresin2 changed slightly (P > 0.05). Phosphorylation of p38, JNK, p65, ikka/ß and ERK peaked at 15 min in the LPS group, while phosphorylation of p-p38 and p-ERK weakened 30 min and 60 min after treatment with Maresin2. CONCLUSIONS: Maresin2 inhibits inflammatory cytokine secretion but enhances phagocytosis via the MAPK/NF-κB pathway in BMDCs, which may contribute to negatively regulating inflammation.
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Li-rich disordered rock-salt oxides (DRX) are considered an attractive cathode material in the future battery field due to their excellent energy density and specific capacity. Nevertheless, anionic redox provides high capacity while causing O2 over-oxidation to O2, resulting in voltage hysteresis and capacity decay. Herein, the crystal structure of Li1.3Mn0.4Ti0.3O1.7F0.3 (LMTOF) cathode is stabilized by using sodium carboxymethylcellulose (CMC) binders replacing traditional polyvinylidene difluoride (PVDF) binders. The electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT) reveal that the CMC-based LMTOF electrode has higher electronic conductivity and lithium-ion diffusion kinetics. Moreover, CMC has been demonstrated to improve the O2- reversibility, reduce the amounts of byproducts from electrolyte decomposition and suppress transition metal dissolution by Na+/Li+ exchange reaction. Furthermore, the CMC-based LMTOF electrode also exhibits less volume change upon lithiation/delithiation processes compared to the PVDF-based electrode, resulting in enhanced structural stability during cycling. Benefiting from these features, the CMC binders can effectively improve the cycling life and rate performance of the LMTOF cathode, and the CMC-based LMTOF electrode shows good capacity retention of 94.5 % after 30 cycles at 20 mA/g and 66.7 % after 100 cycles at 200 mA/g. This finding indicates that CMC as a binder can efficiently stabilize the structure and improve the electrochemical performance of Li-rich disordered rock-salt oxides cathode, making it possible for practical Li-ion battery applications.
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BACKGROUND: Despite promising overall survival of stage I lung adenocarcinoma (LUAD) patients, 10-25 % of them still went through recurrence after surgery. [1] While it is still disputable whether adjuvant chemotherapy is necessary for stage I patients. [2] IASLC grading system for non-mucinous LUAD shows that minor high-grade patterns are significant indicator of poor prognosis. [3] Other risk factors, such as, pleura invasion, lympho-vascular invasion, STAS, etc. are also related to poor prognosis. [4-6] There still lack evidence whether IASLC grade itself or together with other risk factors can guide the use of adjuvant therapy in stage I patients. In this article, we tried to establish a multi-variable recurrence prediction model for stage I LUAD patients that is able to identify candidates of adjuvant chemotherapy. METHODS: We retrospectively collected patients who underwent lung surgery from 2018.8.1 to 2018.12.31 at our institution and diagnosed with lung adenocarcinoma pT1-2aN0M0 (stage I). Clinical data, manifestation on CT scan, pathologic features, driver gene mutations and follow-up information were collected. Cox proportional hazards regression analyses were performed utilizing the non-adjuvant cohort to predict disease free survival (DFS) and a nomogram was constructed and applied to the total cohort. Kaplan-Meier method was used to compare DFS between groups. Statistical analysis was conducted by R version 3.6.3. FINDINGS: A total of 913 stage I LUAD patients were included in this study. Median follow-up time is 48.1 months.4-year and 5-year DFS are 92.9 % and 89.6 % for the total cohort. 65 patient experienced recurrence or death. 4-year DFS are 97.0 %,94.6 % and 76.2 %, and 5-year DFS are 95.5 %, 90.0 % and 74.1 % in IASLC Grade1, 2 and 3, respectively(p < 0.0001). High-risk patients defined by single risk factors, such as, IASLC grade 3, pleura invasion, STAS, less LN resected could not benefit from adjuvant therapy. A LASSO-COX regression model was built and patients are divided into high-risk and low-risk groups. In the high-risk group, patients underwent adjuvant chemotherapy have longer DFS than those who did not (p = 0.024), while in the low-risk group, patients underwent adjuvant chemotherapy have inferior DFS than those who did not (p < 0.001). INTERPRETATION: IASLC grading is a significant indicator of DFS, however it could not guide adjuvant therapy in our stage I LUAD cohort. Growth patterns and T indicators together with other risk factors could identify high-risk patients that are potential candidate of adjuvant therapy, including some stage IA LUAD patients.
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Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Quimioterapia Adjuvante , Estadiamento de Neoplasias , PrognósticoRESUMO
Owing to the outstanding comprehensive properties of high energy density, excellent cycling ability, and reasonable cost, Ni-rich layered oxides (NCM) are the most promising cathode for lithium-ion batteries (LIBs). To further enhance the specific capacity of Ni-rich layered oxides, it is necessary to increase the cut-off voltage to a higher level. However, a higher cut-off voltage can lead to substantial structural changes and trigger interface side reactions, presenting significant challenges for practical applications (cycle life and safety). Herein, to solve above issues, tris(hexafluoroisopropyl)borate (TFPB) is introduced as a high voltage electrolyte additive for LiNi0.90Co0.06Mn0.04O2 cathode. Based on detail in situ/ex situ characterization, this study proves that TFPB forms a protective solid-state interphase (SEI) layer on the Li-anode. Additionally, derivatives of TFPB are easily oxidatively decomposed to create a dense cathode electrolyte interphase (CEI) film on the cathode. This CEI film effectively prevents the continuous oxidation of the electrolyte and mitigates the adverse effects of HF on the battery. Benefit from the protective SEI and CEI layer, the LiNi0.90Co0.06Mn0.04O2||Li battery with a TFPB-containing electrolyte maintains an unprecedented level of performance, with a capacity retention of 89.1% after 100 cycles under the ultrahigh cut-off voltage of 4.6 V (vs Li/Li+).
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Construction of ordered structures that respond rapidly to environmental stimuli has fascinating possibilities for utilization in energy storage, wearable electronics, and biotechnology. Silicon/carbon (Si/C) anodes with extremely high energy densities have sparked widespread interest for lithium-ion batteries (LIBs), while their implementation is constrained via mechanical structure deterioration, continued growth of the solid electrolyte interface (SEI), and cycling instability. In this study, a piezoelectric Bi0.5 Na0.5 TiO3 (BNT) layer is facilely deposited onto Si/C@CNTs anodes to drive piezoelectric fields upon large volume expansion of Si/C@CNTs electrode materials, resulting in the modulation of interfacial Li+ kinetics during cycling and providing an electrochemical reaction with a mechanically robust and chemically stable substrate. In-depth investigations into theoretical computation, multi-scale in/ex situ characterizations, and finite element analysis reveal that the improved structural stability, suppressed volume variations, and controlled ion transportation are responsible for the improvement mechanism of BNT decorating. These discoveries provide insight into the surface coupling technique between mechanical and electric fields to control the interfacial Li+ kinetics behavior and improve structural stability for alloy-based anodes, which will also spark a great deal attention from researchers and technologists in multifunctional surface engineering for electrochemical systems.
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Recently, the development of cathode materials is becoming an important issue for lithium-ion batteries (LIBs). Compared with inorganic cathodes, the organic cathodes are developing rapidly, ascribing to their distinct merits in light weight, low cost, massive organic resources and high capacity. In this paper, a cost-efficiency naphthaldiimide (NDI) based derivative, 2,7-bis(2-((2-hydroxyethyl) amino) ethyl) benzo[lmn] [3,8] phenanthroline-1,3,6,8(2H, 7H)-tetraone (NDI-NHOH), was used as organic cathode in LIBs. The NDI-NHOH was synthesized easily via one-step process, and it showed very high thermal stability. Through mixing NDI-NHOH with acetylene black and polyvinylidene fluoride (weight ratio of 6:3:1) as composite cathode in lithium-metal based LIBs, the NDI-NHOH presented versatile electrochemical properties. From cyclic voltammetry (CV) test, it exhibited two reversible peaks for oxidation and reduction in the first cycle, respectively. Notably, the oxidation and reduction peaks were located at 2.54, 3.22 and 2.14, 2.32 V vs. Li+/Li, respectively. By employing NDI-NHOH as cathode, it demonstrated a specific capacity of about 80 mAh g-1 in the range of 1.5-3.5 V, where the batteries retained a capacity retention of 50% over 20 cycles. According to the LIBs study, it suggests that the NDI-NHOH-based derivative shows a potentially promising candidate as efficient organic cathode materials for high-performance metal-ions batteries.
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Background: Intraoperative frozen section (FS) analysis has been used to guide the extent of resection in patients with solitary pulmonary nodules (SPNs), but its accuracy varies greatly among different hospitals. Artificial intelligence (AI) and multidimensional data technology are developing rapidly these years, meanwhile, surgeons need better methods to guide the surgical strategy of SPNs. We established predicting models combining FS results with multidimensional perioperative clinical features using logistic regression analysis and the random forest (RF) algorithm to get more accurate extent of SPN resection. Methods: Patients with peripheral SPNs who underwent FS-guided surgical resection at the Shanghai Chest Hospital (January 2017-December 2018) were retrospectively examined (N=3,089). The accuracy of intraoperative FS-guided resection extent was analyzed and used as Model 1. The clinical features (sex, age, CT features, tumor markers, smoking history, lesion size and nodule location) of patients were collected, and Models 2 and 3 were established using logistic regression and RF algorithms to combine the FS with clinical features. We confirmed the performance of these models in an external validation cohort of 117 patients from Hwa Mei Hospital, University of Chinese Academy of Science (Ningbo No. 2 Hospital). We compared the effectiveness in classifying low/high-risk groups of SPN among them. Results: The accuracy of FS analysis was 61.3%. Model 3 exhibited the best diagnostic accuracy and had an area under the curve of 0.903 in n the internal validation cohort and 0.919 in the external validation cohort. The calibration plots and net reclassification index (NRI) of Model 3 also exhibited significantly better performance than the other models. Improved diagnostic accuracy was observed in in both internal and external validation cohort. Conclusions: Using an RF algorithm, clinical characteristics can be combined with intraoperative FS analysis to significantly improve intraoperative judgment accuracy for low- and high-risk tumors, and may serve as a reliable complementary method when FS evaluation is equivocal, improving the accuracy of the extent of surgical resection.
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BACKGROUND: Neoadjuvant immunotherapy is emerging as novel effective intervention in lung cancer, but study to unearth effective surrogates indicating its therapeutic outcomes is limited. We investigated the genetic changes between non-small cell lung cancer (NSCLC) patients with varied response to neoadjuvant immunotherapy and discovered highly potential biomarkers with indicative capability in predicting outcomes. METHODS: In this study, 3 adenocarcinoma and 11 squamous cell carcinoma NSCLC patients were treated by neoadjuvant immunotherapy with variated regimens followed by surgical resection. Treatment-naive FFPE or fresh tissues and blood samples were subjected to whole-exome sequencing (WES). Genetic alternations were compared between differently-responded patients. Findings were further validated in multiple public cohorts. RESULTS: DNA damage repair (DDR)-related InDel signatures and DDR-related gene mutations were enriched in better-responded patients, i.e., major pathological response (MPR) group. Besides, MPR patients exhibited provoked genome instability and unique homologous recombination deficiency (HRD) events. By further inspecting alternation status of homology-dependent recombination (HR) pathway genes, the clonal alternations were exclusively enriched in MPR group. Additionally, associations between HR gene alternations, percentage of viable tumor cells and HRD event were identified, which orchestrated tumor mutational burden (TMB), mutational intratumor heterogeneity (ITH), somatic copy number alteration (SCNA) ITH and clonal neoantigen load in patients. Validations in public cohorts further supported the generality of our findings. CONCLUSIONS: We reported for the first time the association between HRD event and enhanced neoadjuvant immunotherapy response in lung cancer. The power of HRD event in patient therapeutic stratification persisted in multifaceted public cohorts. We propose that HR pathway gene status could serve as novel and additional indicators guiding immune-neoadjuvant and immunotherapy treatment decisions for NSCLC patients.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/terapia , Recombinação Homóloga , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/terapia , Mutação , Terapia Neoadjuvante , Resultado do TratamentoRESUMO
OBJECTIVE: Inflammation plays a crucial role in tumorigenesis and progression. Our purpose was to investigate the prognostic value of neutrophil-to-lymphocyte ratio (NLR), systemic inflammation response index (SIRI) and systemic immune-inflammation index (SII), and develop a nomogram to predict the cancer-specific survival (CSS) and disease-free survival (DFS) of stage I lung adenocarcinoma patients. METHODS: 1431 patients undergoing surgical resection with pathologically confirmed stage I lung adenocarcinoma were reviewed. The optimal cut-off values for NLR, SII, and SIRI were defined by the receiver operating characteristic (ROC) curve. Cox proportional hazards regression analyses were performed to recognize factors significantly correlated with CSS and DFS to construct the nomogram. The value of adjuvant chemotherapy on model-defined high-risk and low-risk patients was further explored. RESULTS: The cohort had a median follow-up time of 63 months. Multivariate analysis revealed that higher NLR (≥2.606), higher SIRI (≥0.705), higher SII (≥580.671), later T stage, histological pattern with solid or micropapillary components and radiologic features with solid nodules were significantly associated with worse CSS and DFS. The concordance index (C-index) of the nomogram established by all these factors was higher than that of the TNM staging system both in CSS (validation set 0.778 vs 0.652) and DFS (validation set 0.758 vs 0.695). Furthermore, the value of the established nomogram on risk stratification in stage I lung adenocarcinoma patients was validated. CONCLUSIONS: Higher NLR, SII and SIRI pretreatment were associated with worse survival outcomes. A practical nomogram based on these three inflammatory biomarkers may help clinicians to precisely stratify stage I lung adenocarcinoma patients into high- and low-risk and implement individualized treatment.
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The development of sufficiently effective catalysts with extremely superior performance for electrocatalytic hydrogen production still remains a formidable challenge, especially in acidic media. Here, we report ultrasmall high-entropy alloy (us-HEA) nanoparticles (NPs) with the best-level performance for hydrogen evolution reaction (HER). The us-HEA (NiCoFePtRh) NPs show an average diameter of 1.68 nm, which is the smallest size in the reported HEAs. The atomic structure, coordinational structure, and electronic structure of the us-HEAs were comprehensively clarified. The us-HEA/C achieves an ultrahigh mass activity of 28.3 A mg-1noble metals at -0.05 V (vs the reversible hydrogen electrode, RHE) for HER in 0.5 M H2SO4 solution, which is 40.4 and 74.5 times higher than those of the commercial Pt/C and Rh/C catalysts, respectively. Moreover, the us-HEA/C demonstrates an ultrahigh turnover frequency of 30.1 s-1 at 50 mV overpotential (41.8 times higher than that of the Pt/C catalyst) and excellent stability with no decay after 10â¯000 cycles. Operando X-ray absorption spectroscopy and theoretical calculations reveal the actual active sites, tunable electronic structures, and a synergistic effect among five elements, which endow significantly enhanced HER activity. This work not only engineers a general and scalable strategy for synthesizing us-HEA NPs and elucidates the complex structural information and catalytic mechanisms of multielement HEA system in depth, but also highlights HEAs as sufficiently advanced catalysts and accelerates the research of HEAs in energy-related applications.
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Colloidal CdSe nanoplatelets (NPLs) have substantial potential in light-emitting applications because of their quantum-well-like characteristics. The self-trapped state (STS), originating from strong electron-phonon coupling (EPC), is promising in white light luminance because of its broadband emission. However, achieving STS in CdSe NPLs is extremely challenging because of their intrinsic weak EPC nature. Herein, we developed a strong STS emission in the spectral range of 450-600 nm by building superlattice (SL) structures with colloidal CdSe NPLs. We demonstrated that STS is generated via strong coupling of excitons and zone-folded longitudinal acoustic phonons with formation time of â¼450 fs and localization length of â¼0.56 nm. The Huang-Rhys factor, describing the EPC strength in SL structure, is estimated to be â¼19.9, which is much larger than that (â¼0.1) of monodispersed CdSe NPLs. Our results provide an in-depth understanding of STS and a platform for generating and manipulating STS by designing SL structures.
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BACKGROUND: Repeated assessment of patient recovery after discharge is challenging. This study used a popular messenger application to remotely collect patient self-reported symptoms and their severity so as to monitor patient recovery and identify the factors affecting the recovery of symptoms following lung cancer surgery. METHODS: This prospective observational study was conducted at a single tertiary lung cancer center in China between November 2018 and June 2019. Participants received demonstration videos and repeated symptom surveys regarding pain and cough severity (assessed using numeric rating scores of 0-10 for pain and 0-6 for cough) at 2, 4, 6, 8, and 12 weeks after discharge via a smartphone program bound to the WeChat application. Patients who responded to at least 3 of the 5 post-discharge surveys were included in this study. The data were analyzed to investigate the symptom recovery and its related factors. RESULTS: Of the 826 patients enrolled, 589 (71.3%) responded to at least three surveys. The average pain score reduced from 4.1±2.5 at 2 weeks to 2.2±2.0 at 12 weeks (P<0.001). Factors associated with higher pain severity included the female gender, age over 60 years, thoracotomy, longer operation time (>90 minutes), and prolonged chest tube drainage (>7 days). The average cough score decreased from 2.34±1.30 at 2 weeks to 1.93±1.26 at 12 weeks (P<0.001). Being female and a prolonged operation time (>90 min) were related to increased cough severity. Sublobar resection and limited lymphadenectomy may contribute to lower cough severity post-surgery. CONCLUSIONS: The messenger application-based remote monitoring successfully collected post-discharge symptom information and identified factors associated with recovery following lung surgery.
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BACKGROUND: The recent novel conception of neoadjuvant immunotherapy has generated interest among surgeons worldwide, especially the lack of experience involving surgical treatment for the neoadjuvant immunotherapy population. METHODS: Patients with non-small cell lung cancer (NSCLC), who underwent neoadjuvant immunotherapy or chemo-immunotherapy, were retrospectively collected between September 2018 and April 2020. Demographic data, pathological and clinical features, therapeutic regimens and outcome data of all individuals were collected by retrospective chart review. Operative details, information of neoadjuvant therapy, were also abstracted. RESULTS: In total, 31 patients were included in the final analysis. The patients' median age was 61 years. In total, 29 of the patients were males, while 2 were females. Patients received a median of 3 doses before resection. The median duration from final treatment to surgery was 34 days. After neoadjuvant treatment, post-treatment computed tomography scan showed that 24 patients had partial response. In total, 12 of 31 patients had a major pathological response, 15 pathological downstaging. Three patients had no residual viable tumor. A positive surgical margin was identified in 7 cases. One or more postoperative complications occurred in 18 of all 31 patients. In total, 26 patients underwent next-generation sequencing before surgery in total. Among them, 2 patients were detected STK11 mutations, none of whom had a major pathological response by final pathological examination. CONCLUSIONS: Pulmonary resection after neoadjuvant immunotherapy or chemo-immunotherapy for resectable NSCLC appears to be safe with low operative mortality and morbidity rate in the current population.
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Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/terapia , Adulto , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/imunologia , Feminino , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/imunologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos RetrospectivosRESUMO
Fluorographites (CFx ) are ultrahigh-energy-density cathode materials for alkaline-metal primary batteries. However, they are generally not rechargeable. To elucidate the reaction mechanism of CFx cathodes, in situ transmission electron microscopy characterizations and ab initio calculations are employed. It is found that it is a two-phase mechanism upon K/Na/Li ion insertion; crystalline KF (crystalline NaF nanoparticles and amorphous LiF) is generated uniformly within the amorphous carbon matrix, retaining an unchanged volume during the discharge process. The diffusivity for K/Na/Li ion migration within the CFx is ≈2.2-2.5 × 10-12 , 3.4-5.3 × 10-12 , and 1.8-2.5 × 10-11 cm2 s-1 , respectively, which is comparable to the diffusivity of K/Na/Li ions in liquid-state cells. Encouraged by the in situ transmission electron microscopy (TEM) results, a new rechargeable all-solid-state Li/CFx battery is further designed that shows a part of the reversible specific discharge capacity at the 2nd cycle. These findings demonstrate that a solid-state electrolyte provides a different reaction process compared with a conventional liquid electrolyte, and enables CFx to be partly rechargeable in solid-state Li batteries.
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Transition metal (TM)-based layered oxides NaTMO2 (TM = Fe, Ni, Co, Mn, etc.) have been intensively pursued as high-capacity cathode materials for Na-ion batteries. Nevertheless, they still suffer from fast capacity loss and voltage decay, as a result of the layered structure instability upon extended electrochemical cycling. The mechanism underlying such instability remains poorly understood. Here we unravel the TM migrations and structural evolution of a quaternary NaNi0.3Co0.12Mn0.18Fe0.4O2 compound during electrochemical cycling using atomic-resolution electron microscopy and associated spectroscopies. We discover successive migrations of TM ions to Na layers that account for structure and performance degradations. The Fe ions migrate into the interstices of both tetrahedra and octahedra of the layers; on the contrary, the Ni ions migrate predominantly in the octahedral ones, and the Mn and Co ions mostly remain in the TM layers. Direct atomic-level observations of the TM migration process upon cycling offer deep insight into designing high-capacity and long-life span cathode materials for sodium-ion batteries.
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Honeycomb-layered phases Na3M2XO6 (M = Ni, Cu, Co; X = Sb, Bietc.) have been intensively pursued as high-voltage and high-rate capability cathode materials for Na-ion batteries (NIBs), but the crystal structure is not well elucidated. Herein, structural analysis was conducted on pristine Na3Ni2SbO6 material using electron microscopy and associated spectroscopies to reveal its crystallographic features. Experimental observations along multiple zone axes indicate that structural disorder is intrinsic in the pristine Na3Ni2SbO6, characteristic of randomly stacked layers with three variants of monoclinic structure. Stacking disorder is demonstrated by the non-vertical relationship of adjacent Ni2SbO6 layers in [100] zone axis, the different Ni/Sb atomic arrangements in [010] zone axis, and the Ni/Sb random overlap in [001] zone axis. The insight on the structural disorder may inspire studies on their phase transformations upon cycling and provide some clues to potentially solve the voltage/capacity decay problems of these honeycomb-layered materials.
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Metal-based nanocatalysts supported on carbon have significant prospect for industry. However, a straightforward method for efficient and stable nanocatalysts still remains extremely challenging. Inspired by the structure and comptosition of cell walls and membranes, an ion chemical bond anchoring, an in situ carbonization coreduction process, is designed to obtain composite catalysts on N-doped 2D carbon (C-N) loaded with various noble and non-noble metals (for example, Pt, Ru, Rh, Pd, Ag, Ir, Au, Co, and Ni) nanocatalysts. These 2 nm particles uniformly and stably bond with the C-N support since the agglomeration and growth are suppressed by anchoring the metal ions on the cell wall and membrane during the carbonization and reduction reactions. The Pt@C-N exhibits excellent catalytic activity and long-term stability for the hydrogen evolution reaction, and the relative overpotential at 100 mA cm-2 is only 77 mV, which is much lower than that of commercial Pt/C and Pt single-atom catalysts reported recently.
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BACKGROUND: Peroxisome proliferator-activated receptor γ2 (PPARγ2) plays a critical role in the regulation of adipocyte differentiation and adipocytokine production. The Pro12Ala variant is the most common mutation in the PPARγ2 gene. Its effect appears to be sensitive to dietary factors, such as docosahexaenoic acid (DHA) level. The purpose of this study was to investigate the interaction effect between PPARγ2 Pro12Ala variant and DHA on the phenotypes of adipocytes. METHODS: We generated stable 3T3-L1 cell lines expressing wild-type PPARγ2 or PPARγ2 Pro12Ala variant. These two cell lines were cultured with different concentrations of DHA (0, 50, 200 umol/L). Then Oil red O staining was used to observe cell differentiation and the degree of lipid accumulation, TUNNEL assay was used to detect cell apoptosis, and ELISA assays were used to detect the changes of TNF-α, resistin and adiponectin levels in cell culture supernatant. RESULTS: PPARγ2 Pro12Ala variant reduced lipid droplet accumulation in 3T3-L1 preadipocytes treated with or without 50 µmol/L DHA, but not with 200 µmol/L DHA, compared to that of wild-type PPARγ2. PPARγ2 reduced resistin production and increased adiponectin production in 3T3-L1 adipocytes, whereas PPARγ2 Pro12Ala variant diminished these effects. However, the absence of DHA blocked PPARγ2 Ala12 variant-induced effects on adiponectin production. There was no significant difference in TNF-α secretion between wild-type PPARγ2 and PPARγ2 Pro12Ala cells whether with or without DHA. CONCLUSION: These results indicated that the effects of PPARγ2 Pro12Ala variant were dependent on DHA concentration.
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Designing electrode materials with engineered exposed facets provides a novel strategy to improve their electrochemical properties. However, the controllability of the exposed facet remains a daunting challenge, and a deep understanding of the correlation between exposed facet and Li+-transfer behavior has been rarely reported. In this work, single-crystal α-Fe2O3 hexagonal nanosheets with an exposed (001) facet are prepared with the assistance of aluminum ions through a one-step hydrothermal process, and structural characterizations reveal an Al3+-concentration-dependent-growth mechanism for the α-Fe2O3 nanosheets. Furthermore, such α-Fe2O3 nanosheets, when used as lithium-ion battery anodes, exhibit high specific capacity (1261.3 mAh g-1 at 200 mA g-1), high rate capability (with a reversible capacity of approximately 605 mAh g-1 at 10 A g-1), and excellent cyclic stability (with a capacity of over 900 mAh g-1 during 500 cycles). The superior electrochemical performance of α-Fe2O3 nanosheets is attributed to the pseudocapacitive behavior, Al-doping in the α-Fe2O3 structure, and improved Li+-transfer property across the (001) facet, as elucidated by first-principles calculations based on density functional theory. These results reveal the underlying mechanism of Li+ transfer across different facets and thus provide insights into the understanding of the excellent electrochemical performance.