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Despite wide studies demonstrating the versatility of the metal oxide-zeolite (OXZEO) catalyst concept to tackle the selectivity challenge in syngas chemistry, the active sites of metal oxides and the mechanism of CO/H2 activation remain to be elucidated. Herein, we demonstrate experimentally the role of Cr in zinc-chromium oxides and unveil visually, for the first time, the active sites for CO activation employing scanning transmission electron microscopy-electron energy loss spectroscopy using the volumetric density of surface carbon species as a descriptor. The ZnCr2O4 spinel surface with atomic ZnOx overlayer is the most active site for C-O bond dissociation, particularly at the narrow ZnCr2O4(110) facets constrained between the (311) and (111) facets, followed by the Cr-doped wurtzite ZnO surface. In comparison, the surfaces of ZnCr2O4 with aggregated ZnOx overlayers, pure ZnO, and the stoichiometric ZnCr2O4 exhibit a significantly lower activity. In situ synchrotron-based vacuum ultraviolet photoionization mass spectrometric study on different temperature programmed surface reactions with isotopes of C18O, 13CO, and D2 validates direct CO dissociation over ZnCrn oxides in CO, forming CH2 and further to hydrocarbons if H2 is present and CH2CO intermediates in syngas. The activity of CO dissociation and hydrogenation over ZnCrn oxides correlates well with the syngas-to-light-olefins activity of ZnCrn-SAPO-18 composite catalysts as a function of the Cr/Zn ratio.
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The rapid proliferation of power sources equipped with lithium-ion batteries poses significant challenges in terms of post-scrap recycling and environmental impacts, necessitating urgent attention to the development of sustainable solutions. The cathode direct regeneration technologies present an optimal solution for the disposal of degraded cathodes, aiming to non-destructively re-lithiate and straightforwardly reuse degraded cathode materials with reasonable profits and excellent efficiency. Herein, a potential-regulated strategy is proposed for the direct recycling of degraded LiFePO4 cathodes, utilizing low-cost Na2SO3 as a reductant with lower redox potential in the alkaline systems. The aqueous re-lithiation approach, as a viable alternative, not only enables the re-lithiation of degraded cathode while ignoring variation in Li loss among different feedstocks but also utilizes the rapid sintering process to restore the cathode microstructure with desirable stoichiometry and crystallinity. The regenerated LiFePO4 exhibits enhanced electrochemical performance with a capacity of 144 mA h g-1 at 1 C and a high retention of 98% after 500 cycles at 5 C. Furthermore, this present work offers considerable prospects for the industrial implementation of directly recycled materials from lithium-ion batteries, resulting in improved economic benefits compared to conventional leaching methods.
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With the development of electric vehicles, exploiting anode materials with high capacity and fast charging capability is an urgent requirement for lithium-ion batteries (LIBs). Borophene, with the merits of high capacity, high electronic conductivity and fast diffusion kinetics, holds great potential as anode for LIBs. However, it is difficult to fabricate for the intrinsic electron-deficiency of boron atom. Herein, heterogeneous-structured MoB2 (h-MoB2) with amorphous shell and crystalline core, is prepared by solid phase molten salt method. As demonstrated, crystalline core can encapsulate the honeycomb borophene within two adjacent Mo atoms, and amorphous shell can accommodate more lithium ions to strengthen the lithium storage capacity and diffusion kinetics. According to theoretical calculations, the lithium adsorption energy in MoB2 is about -2.7 eV, and the lithium diffusion energy barrier in MoB2 is calculated to be 0.199 eV, guaranteeing the enhanced adsorption capability and fast diffusion kinetic behavior of Li+ ions. As a result, h-MoB2 anode presents high capacity of 798 mAh g-1 at 0.1 A g-1, excellent rate performance of 183 mAh g-1 at 5 A g-1 and long-term cyclic stability for 1200 cycles. This work may inspire ideas for the fabrication of borophene analogs and two-dimensional metal borides.
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Ammonium vanadates, featuring an NâH···O hydrogen bond network structure between NH4 + and VâO layers, have become popular cathode materials for aqueous zinc-ion batteries (AZIBs). Their appeal lies in their multi-electron transfer, high specific capacity, and facile synthesis. However, a major drawback arises as Zn2+ ions tend to form bonds with electronegative oxygen atoms between VâO layers during cycling, leading to irreversible structural collapse. Herein, Li+ pre-insertion into the intermediate layer of NH4V4O10 is proposed to enhance the electrochemical activity of ammonium vanadate cathodes for AZIBs, which extends the interlayer distance of NH4V4O10 to 9.8 Å and offers large interlaminar channels for Zn2+ (de)intercalation. Moreover, Li+ intercalation weakens the crystallinity, transforms the micromorphology from non-nanostructured strips to ultrathin nanosheets, and increases the level of oxygen defects, thus exposing more active sites for ion and electron transport, facilitating electrolyte penetration, and improving electrochemical kinetics of electrode. In addition, the introduction of Li+ significantly reduces the bandgap by 0.18 eV, enhancing electron transfer in redox reactions. Leveraging these unique advantages, the Li+ pre-intercalated NH4V4O10 cathode exhibits a high reversible capacity of 486.1 mAh g-1 at 0.5 A g-1 and an impressive capacity retention rate of 72% after 5,000 cycles at 5 A g-1.
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Two-dimensional (2D) materials are promising successors for silicon transistor channels in ultimately scaled devices, necessitating significant research efforts to study their behavior at nanoscopic length scales. Unfortunately, current research has limited itself to direct patterning approaches, which limit the achievable resolution to the diffraction limit and introduce unwanted defects into the 2D material. The potential of multi-patterning to fabricate 2D materials features with unprecedented precision and low complexity at large scale is demonstrated here. By combining lithographic patterning of a mandrel and bottom-up self-expansion, this approach enables pattern resolution one order of magnitude below the lithographical resolution. In-depth characterization of the self-expansion double patterning (SEDP) process reveals the ability to manipulate the critical dimension with nanometer precision through a self-limiting and temperature-controlled oxidation process. These results indicate that the SEDP process can regain the quality and morphology of the 2D material, as shown by high-resolution microscopy and optical spectroscopy. This approach is shown to open up new avenues for research into high-performance, ultra-scaled 2D materials devices for future electronics.
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Cutaneous squamous cell carcinoma (cSCC) is the second most prevalent form of skin cancer, with an escalating incidence rate and a notable potential (up to 5%) for metastasis. Ultraviolet radiation (UVA and UVB) exposure is the primary risk factor for cSCC carcinogenesis, with literature suggesting ultraviolet radiation (UVR) promotes vascular endothelial growth factor A (VEGFA) expression. This study aims to investigate UVR-induced upregulation of VEGFA and explore combination therapeutic strategies. The skin squamous cell carcinoma cell line A431 was exposed to specific durations of ultraviolet radiation. The effect of emodin on ATR/SerRS/VEGFA pathway was observed. The cell masses were also transplanted subcutaneously into mice (n = 8). ATR inhibitor combined with emodin was used to observe the growth and angiogenesis of the xenografts. The results showed that UV treatment significantly enhanced the phosphorylation of SerRS and the expression level of VEGFA in A431 cells (p < 0.05). Treatment with emodin significantly inhibited this expression (p < 0.05), and the combination of emodin and ATR inhibitor further enhanced the inhibitory effect (p < 0.05). This phenomenon was further confirmed in the xenograft model, which showed that the combination of ATR inhibitor and emodin significantly inhibited the expression of VEGFA to inhibit angiogenesis (p < 0.05), thus showing an inhibitory effect on cSCC. This study innovatively reveals the molecular mechanism of UV-induced angiogenesis in cSCC and confirms SerRS as a novel target to inhibit cSCC angiogenesis and progression in vitro and in vivo studies.
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Proteínas Mutadas de Ataxia Telangiectasia , Carcinoma de Células Escamosas , Neovascularização Patológica , Neoplasias Cutâneas , Raios Ultravioleta , Fator A de Crescimento do Endotélio Vascular , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/metabolismo , Raios Ultravioleta/efeitos adversos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/tratamento farmacológico , Humanos , Camundongos , Neovascularização Patológica/metabolismo , Linhagem Celular Tumoral , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto , Transdução de Sinais/efeitos dos fármacos , Camundongos Nus , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Emodina/farmacologia , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , AngiogêneseRESUMO
Background: Revascularized patients still experience adverse cardiovascular events. This is particularly true for elderly patients over the age of 65, as they often have more co-morbid vascular conditions. It is important to develop a tool to assist clinicians in comprehensively assessing these patients' prognosis. The objective of this study is to create a comprehensive visual nomogram model combining clinical and physiological assessments to predict outcomes in elderly patients undergoing percutaneous coronary intervention (PCI). Methods: This study is a retrospective investigation of patients who underwent PCI between January 2016 and December 2017. A total of 691 patients with 1461 vessels were randomly divided into a training (n = 483) and a validation set (n = 208). A multivariate Cox regression model was employed using the training set to select variables for constructing a nomogram. The performance of the nomogram was assessed through the receiver operating characteristic curve (ROC) and calibration curves to evaluate its discrimination and predictive accuracy. To further assess the clinical usefulness, Kaplan-Meier curve analysis and landmark analysis were conducted. Results: Independent risk factors, including diabetes mellitus (DM), post-PCI quantitative flow ratio (QFR), previous myocardial infarction (MI), and previous PCI, were contained in the nomogram. The nomogram exhibited a good area under the curve (AUC) ranging from 0.742 to 0.789 in the training set, 0.783 to 0.837 in the validation set, and 0.764 to 0.786 in the entire population. Calibration curves demonstrated a well-fitted curve in all three sets. The Kaplan-Meier curves showed clear separation and the patients with higher scores in the nomogram model exhibited a higher incidence of target vessel revascularization (TVR) (7.99% vs. 1.24% for 2-year, p < 0.001 and 13.54% vs. 2.23% for 5-years, p < 0.001, respectively). Conclusions: This study has developed the visually intuitive nomogram to predict the 2-year and 5-year TVR rates for elderly patients who underwent PCI. This tool provides more accurate and comprehensive healthcare guidance for patients and their physicians.
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Supercapacitors with transition bimetallic oxides as pseudocapacitive materials have been of wide concern for their excellent energy storage performance. In this work, a simple coprecipitation method was used to synthesize the precursor, followed by calcination to prepare Ni-Cu bimetallic oxide materials. The structure, morphology and properties of the materials prepared by different precipitating agents and different calcination temperatures of NCO-H2C2O4 precursor were investigated. The optimum precipitant was determined to be H2C2O4, and Ni-Cu nanoparticles with regular lamellar microstructure were obtained at the calcination temperature of 400 °C. The nanostructure and morphology provide a large active channel for the rapid diffusion of electrolyte ions, and the specific capacitance of NCO-H2C2O4-400 electrode material can reach 740.31 F/g Cs at 1 A/g. The investigation of charge storage mechanism shows that the contribution rate of capacitance and diffusion control is about 37.9% and 67.2%, respectively. The electrochemical test results of the asymmetric supercapacitors (ASC) constructed with NCO-H2C2O4-400 and activated carbon show that the specific capacitance, energy density, and power density of the capacitor are 52.66 F/g, 16.45 Wh/kg, and 759.51 W/kg, respectively. Even after 5000 charge/discharge cycles at 5 A/g, it can still keep 90.57% of its initial capacity. This work not only provides competitive electrode materials for energy storage devices but also provides a feasible strategy for producing complex transition metal oxide materials with high capacitance performance.
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The removal of carbonyl sulfide (COS) commonly contained in natural gas is of great significance but still very challenging via a widely employed absorption process due to its low reactivity and solubility in various commercial solvents. Artificial intelligence (AI) is playing an increasingly important role in the exploration of desulfurization solvents. However, practically feasible AI models still lack a thorough understanding of the reaction mechanisms. Machine learning (ML) models established on chemical mechanisms exhibit enhanced chemical interpretability and prediction performance. In this study, we constructed a series of solvent molecules with varying functional groups, including linear aliphatic amines, cyclic aliphatic amines, and aromatic amines and proposed a three-step reaction pathway to dissect the effects of charge and steric hindrance of different substituents on their reaction rates with COS. Chemical descriptors, based on electrostatic potential (ESP), average local ionization energy (ALIE) theory, Hirshfeld charges, and Fukui functions, were used to correlate and predict the electrophilic reactivity of amine groups with COS. Substituents influence the reaction rate by changing the attraction interaction of amine groups to COS molecules and the electron rearrangement in the electrophilic reaction. Furthermore, they have more pronounced steric effects on the reaction rate in the linear amines. The descriptors N_ALIE and q(N) were found to be crucial in predicting the reactivity of amine groups with COS. Present study provides a comprehensive understanding of the reaction mechanisms of COS with amine compounds, offers specific chemical principles for the development of chemistry-driven ML models, sheds light on other types of electrophilic reactions occurring on amine and phosphine groups, and guides the development of chemical solvents in gas absorption processes.
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Frizzled receptors (FZDs) are class-F G-protein-coupled receptors (GPCRs) that function in Wnt signalling and are essential for developing and adult organisms1,2. As central mediators in this complex signalling pathway, FZDs serve as gatekeeping proteins both for drug intervention and for the development of probes in basic and in therapeutic research. Here we present an atomic-resolution structure of the human Frizzled 4 receptor (FZD4) transmembrane domain in the absence of a bound ligand. The structure reveals an unusual transmembrane architecture in which helix VI is short and tightly packed, and is distinct from all other GPCR structures reported so far. Within this unique transmembrane fold is an extremely narrow and highly hydrophilic pocket that is not amenable to the binding of traditional GPCR ligands. We show that such a pocket is conserved across all FZDs, which may explain the long-standing difficulties in the development of ligands for these receptors. Molecular dynamics simulations on the microsecond timescale and mutational analysis uncovered two coupled, dynamic kinks located at helix VII that are involved in FZD4 activation. The stability of the structure in its ligand-free form, an unfavourable pocket for ligand binding and the two unusual kinks on helix VII suggest that FZDs may have evolved a novel ligand-recognition and activation mechanism that is distinct from that of other GPCRs.
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Receptores Frizzled/química , Sítios de Ligação , Cristalografia por Raios X , Cisteína/metabolismo , Proteínas Desgrenhadas/metabolismo , Receptores Frizzled/genética , Humanos , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Domínios Proteicos , Via de Sinalização WntRESUMO
BACKGROUND CONTEXT: Lumbar spinal stenosis is one of the most common diseases affecting the elderly that is characterized by the narrowing of the spinal canal and peripheral neural pathways which may cause back pain and neurogenic intermittent claudication in affected patients. Recently, as an alternative treatment between conservative therapy and decompression surgery, interspinous process device (IPD) such as X-stop, Coflex, DIAM, Aperius, Wallis, etc., has gained enough popularity. PURPOSE: The purpose of this study was to evaluate the efficacy and safety of IPD in the treatment of degenerative lumbar spinal stenosis compared with decompression surgery. STUDY DESIGN: This study was a systematic review and meta-analysis of randomized controlled trials. PATIENT SAMPLE: 555 patients' samples were collected for this study. OUTCOME MEASURES: The Visual Analogue Scale and the Oswestry Disability Index were analyzed, as well as the Zurich Claudication Questionnaire For efficacy evaluation. Complication and reoperation rate was utilized for the assessment of safety. METHODS: A comprehensive literature search was performed through Pubmed, EMBASE, Web of Science, and Cochrane Library until October 2023. Among the studies meeting the eligible criteria, any study in which IPD was utilized in the treatment of degenerative lumbar spinal stenosis was included in the current review. For efficacy evaluation, the Visual Analogue Scale and the Oswestry Disability Index were analyzed, as well as the Zurich Claudication Questionnaire. Complication and reoperation rates were utilized for the assessment of safety. RESULTS: Five randomized controlled trials with 555 patients were included. There were no significant differences in VAS leg pain (SMD - 0.08, 95% CI - 0.32 to 0.15) and back pain (SMD 0.09, 95%CI-0.27 to 0.45), ODI scores (MD 1.08, 95% CI - 11.23 to 13.39) and ZCQ physical function (MD-0.09, 95% CI-0.22 to 0.05) for IPD compared with decompression surgery. In terms of ZCQ symptom severity (MD - 0.22, 95% CI - 0.27 to - 016), decompression surgery showed superior to the IPD. As for complications (RR 1.08, 95% CI 0.36 to 3.27), the IPD had no advantages compared to decompression surgery, whereas inferior to it in reoperation rate (RR 2.58, 95% CI 1.67 to 3.96). CONCLUSIONS: This systematic review and meta-analysis indicated no superiority in the clinical outcome for IPD compared with decompression surgery. However, more clinical studies are warranted to determine the efficacy and safety of IPD.
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Descompressão Cirúrgica , Vértebras Lombares , Ensaios Clínicos Controlados Aleatórios como Assunto , Estenose Espinal , Humanos , Estenose Espinal/cirurgia , Vértebras Lombares/cirurgia , Idoso , Descompressão Cirúrgica/métodos , Descompressão Cirúrgica/instrumentação , Degeneração do Disco Intervertebral/cirurgia , Degeneração do Disco Intervertebral/complicações , Resultado do TratamentoRESUMO
OBJECTIVE: This study aims to dissect impacts of exosomes-delivered PD-L1 and CTLA-4 siRNAs on colorectal cancer (CRC) progression and immune responses. METHODS: Exosomes containing PD-L1 siRNA and CTLA-4 siRNA were prepared and utilized to treat CRC cells to evaluate their effects. A tumor-bearing mouse model was established for verification. RESULTS: Exosomes containing PD-L1 siRNA and CTLA-4 siRNA repressed malignant features of CRC cells and restrained tumor growth and activated tumor immune responses in vivo. Co-culture of CRC cells treated with exosomes containing PD-L1 siRNA and CTLA-4 siRNA with human CD8+ T cells increased the percentage of CD8+ T cells, decreased the apoptotic rate of CD8+ T cells, elevated IL-2, IFN-γ, and TNF-α expression in cell supernatants, reduced adherent density of CRC cells, augmented the positive rate of CRC cells, and subdued tumor immune escape. CONCLUSION: Exosomes containing PD-L1 siRNA and CTLA-4 siRNA suppressed CRC progression and enhanced tumor immune responses.
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Neoplasias Colorretais , Exossomos , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , RNA Interferente Pequeno/genética , Evasão Tumoral , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Antígeno CTLA-4/genética , Antígeno CTLA-4/metabolismo , Exossomos/genética , Exossomos/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , RNA de Cadeia DuplaRESUMO
There is currently a lack of scientific bibliometric analyses in the field of Pierre Robin sequence (PRS). Pierre Robin sequence is known for its clinical triad of micrognathia, glossoptosis, airway obstruction, and possible secondary cleft palate. These defects can lead to upper airway obstruction, sleep apnea, feeding difficulties, affect an individual's growth and development, education level, and in severe cases can be life-threatening. Through analysis of literature retrieved from the Web of Science Core Collection (WoSCC) database using Results Analysis and Citation Report and Citespace software, 933 original articles and reviews were included after manual screening. The overall trend for the number of annual publications and citations was increasing. On the basis of the analysis, airway evaluation and treatment, mandibular distraction osteogenesis (MDO), as well as descriptions of PRS characteristics have been the focus of research in this field. In addition, with advances in new technologies such as gene sequencing and expanding understanding of diseases among researchers, research on genetics and etiology related to PRS has become a growing trend.
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Triethylamine is a common volatile organic compound (VOC) that plays an important role in areas such as organic solvents, chemical industries, dyestuffs, and leather treatments. However, exposure to triethylamine atmosphere can pose a serious threat to human health. In this study, gas-sensing semiconductor materials of LaFeO3 nano materials with different Mo-doping ratios were synthesized by the sol-gel method. The crystal structures, micro morphologies, and surface states of the prepared samples were characterized by XRD, SEM, and XPS, respectively. The gas-sensing tests showed that the Mo doping enhanced the gas-sensing performance of LaFeO3. Especially, the 4% Mo-doped LaFeO3 exhibited the highest response towards triethylamine (TEA) gas, a value approximately 11 times greater than that of pure LaFeO3. Meantime, the 4% Mo-doped LaFeO3 sensor showed a remarkably robust linear correlation between the response and the concentration (R2 = 0.99736). In addition, the selectivity, stability, response/recovery time, and moisture-proof properties were evaluated. Finally, the gas-sensing mechanism is discussed. This study provides an idea for exploring a new type of efficient and low-cost metal-doped LaFeO3 sensor to monitor the concentration of triethylamine gas for the purpose of safeguarding human health and safety.
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BACKGROUND: Periodontitis is a chronic inflammatory condition triggered by immune system malfunction. Mitochondrial extracellular vesicles (MitoEVs) are a group of highly heterogeneous extracellular vesicles (EVs) enriched in mitochondrial fractions. The objective of this research was to examine the correlation between MitoEVs and the immune microenvironment of periodontitis. METHODS: Data from MitoCarta 3.0, GeneCards, and GEO databases were utilized to identify differentially expressed MitoEV-related genes (MERGs) and conduct functional enrichment and pathway analyses. The random forest and LASSO algorithms were employed to identify hub MERGs. Infiltration levels of immune cells in periodontitis and healthy groups were estimated using the CIBERSORT algorithm, and phenotypic subgroups of periodontitis based on hub MERG expression levels were explored using a consensus clustering method. RESULTS: A total of 44 differentially expressed MERGs were identified. The random forest and LASSO algorithms identified 9 hub MERGs (BCL2L11, GLDC, CYP24A1, COQ2, MTPAP, NIPSNAP3A, FAM162A, MYO19, and NDUFS1). ROC curve analysis showed that the hub gene and logistic regression model presented excellent diagnostic and discriminating abilities. Immune infiltration and consensus clustering analysis indicated that hub MERGs were highly correlated with various types of immune cells, and there were significant differences in immune cells and hub MERGs among different periodontitis subtypes. CONCLUSION: The periodontitis classification model based on MERGs shows excellent performance and can offer novel perspectives into the pathogenesis of periodontitis. The high correlation between MERGs and various immune cells and the significant differences between immune cells and MERGs in different periodontitis subtypes can clarify the regulatory roles of MitoEVs in the immune microenvironment of periodontitis. Future research should focus on elucidating the functional mechanisms of hub MERGs and exploring potential therapeutic interventions based on these findings.
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Vesículas Extracelulares , Humanos , Aprendizado de Máquina , Algoritmos , Análise por Conglomerados , Biologia ComputacionalRESUMO
Objective: To analyze the effect of additional surgery on the survival and prognosis of high-risk T1 colorectal cancer patients who have undergone endoscopic resection. Methods: The clinical data of patients with high-risk T1 colorectal cancer were retrospectively collected. The patients were divided into the endoscopic resection (ER) plus additional surgical resection (SR) group, or the ER+SR group, and the ER group according to whether additional SR were performed after ER. Baseline data of the patients and information on the location, size, and postoperative pathology of the lesions were collected. Patient survival-related information was obtained through the medical record system and patient follow-up. The primary outcome indicators were the overall survival and the colorectal cancer-specific survival. Univariate Cox regression analysis was used to screen survival-related risk factors and hazard ratio (HR) was calculated. Multivariate Cox regression analysis was used to analyze the independent influencing factors. Results: The data of 109 patients with T1 high-risk colorectal cancer were collected, with 52 patients in the ER group and 57 patients in the ER+SR group. The mean age of patients in the ER group was higher than that in the ER+SR group (65.21 years old vs. 60.54 years old, P=0.035), and the median endoscopic measurement of the size of lesions in the ER group was slightly lower than that in the ER+SR group (2.00 cm vs. 2.50 cm, P=0.026). The median follow-up time was 30.00 months, with the maximum follow-up time being 119 months, in the ER+SR group and there were 4 patients deaths, including one colorectal cancer-related death. Whereas the median follow-up time in the ER group was 28.50 months, with the maximum follow-up time being 78.00 months, and there were 4 patient deaths, including one caused by colorectal cancer. The overall 5-year cumulative survival rates in the ER+SR group and the ER group were 94.44% and 81.65%, respectively, and the cancer-specific 5-year cumulative survival rates in the ER+SR group and the ER group were 97.18% and 98.06%, respectively. The Kaplan-Meier analysis showed no significant difference in the overall cumulative survival or cancer-specific cumulative survival between the ER+SR and the ER groups. Univariate Cox regression analysis showed that age and the number of reviews were the risk factors of overall survival (HR=1.16 and HR=0.27, respectively), with age identified as an independent risk factor of overall survival in the multivariate Cox regression analysis (HR=1.10, P=0.045). Conclusion: For T1 colorectal cancer patients with high risk factors after ER, factors such as patient age and their personal treatment decisions should not be overlooked. In clinical practice, additional caution should be exercised in decision-making concerning additional surgery.
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Neoplasias Colorretais , Humanos , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/mortalidade , Estudos Retrospectivos , Feminino , Masculino , Prognóstico , Idoso , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida , Modelos de Riscos ProporcionaisRESUMO
Optical anisotropy, which is quantified by birefringence (Δn) and linear dichroism (Δk), can significantly modulate the angle-resolved polarized Raman spectroscopy (ARPRS) response of anisotropic layered materials (ALMs) by external interference. This work studies the separate modulation of birefringence on the ARPRS response and the intrinsic response by selecting transparent birefringent crystal α-MoO3 as an excellent platform. It is found that there are several anomalous ARPRS responses in α-MoO3 that cannot be reproduced by the real Raman tensor widely used in non-absorbing materials; however, they can be well explained by considering the birefringence-induced Raman selection rules. Moreover, the systematic thickness-dependent study indicates that birefringence modulates the ARPRS response to render an interference pattern; however, the amplitude of modulation is considerably lower than that by linear dichroism as occurred in black phosphorous. This weak modulation brings convenience to the crystal orientation determination of transparent ALMs. Combining the atomic vibrational pattern and bond polarizability model, the intrinsic ARPRS response of α-MoO3 is analyzed, giving the physical origins of the Raman anisotropy. This study employs α-MoO3 as an example, although it is generally applicable to all transparent birefringent ALMs.
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Nickel sulfides with high theoretical capacity are considered as promising anode materials for sodium-ion batteries (SIBs); however, their intrinsic poor electric conductivity, large volume change during charging/discharging, and easy sulfur dissolution result in inferior electrochemical performance for sodium storage. Herein, a hierarchical hollow microsphere is assembled from heterostructured NiS/NiS2 nanoparticles confined by in situ carbon layer (H-NiS/NiS2 @C) via regulating the sulfidation temperature of the precursor Ni-MOFs. The morphology of ultrathin hollow spherical shells and confinement of in situ carbon layer to active materials provide rich channels for ion/electron transfer and alleviate the effects of volume change and agglomeration of the material. Consequently, the as-prepared H-NiS/NiS2 @C exhibit superb electrochemical properties, satisfactory initial specific capacity of 953.0 mA h g-1 at 0.1 A g-1 , excellent rate capability of 509.9 mA h g-1 at 2 A g-1 , and superior longtime cycling life with 433.4 mA h g-1 after 4500 cycles at 10 A g-1 . Density functional theory calculation shows that heterogenous interfaces with electron redistribution lead to charge transfer from NiS to NiS2 , and thus favor interfacial electron transport and reduce ion-diffusion barrier. This work provides an innovative idea for the synthesis of homologous heterostructures for high-efficiency SIB electrode materials.
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Sodium superionic conductor (NASICON)-type Na3 V2 (PO4 )3 has attracted considerable interest owing to its stable three-dimensional framework and high operating voltage; however, it suffers from a low-energy density due to the poor intrinsic electronic conductivity and limited redox couples. Herein, the partial substitution of Mn3+ for V3+ in Na3 V2 (PO4 )3 is proposed to activate V4+ /V5+ redox couple for boosting energy density of the cathodes (Na3 V2- x Mnx (PO4 )3 ). With the introduction of Mn3+ into Na3 V2 (PO4 )3 , the band gap is significantly reduced by 1.406 eV and thus the electronic conductivity is greatly enhanced. The successive conversions of four stable oxidation states (V2+ /V3+ , V3+ /V4+ , and V4+ /V5+ ) are also successfully achieved in the voltage window of 1.4-4.0 V, corresponding to three electrons involved in the reversible reaction. Consequently, the cathode with x = 0.5 exhibits a high reversible discharge capacity of 170.9 mAh g-1 at 0.5 C with an ultrahigh energy density of 577 Wh kg-1 . Ex-situ x-ray diffraction (XRD) analysis reveals that the sodium-storage mechanism for Mn-doped Na3 V2 (PO4 )3 consists of single-phase and bi-phase reactions. This work deepens the understanding of the activation of reversible three-electron reaction in NASICON-structured polyanionic phosphates and provides a feasible strategy to develop high-energy-density cathodes for sodium-ion batteries.
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Aqueous zinc-ion batteries (AZIBs) have attracted considerable attention due to their low cost and environmental friendliness. However, the rampant dendrite growth and severe side reactions during plating/stripping on the surface of zinc (Zn) anode hinder the practicability of AZIBs. Herein, an effective and non-toxic cationic electrolyte additive of Rb2 SO4 is proposed to address the issues. The large cation of Rb+ is preferentially adsorbed on the surface of Zn metal to induce a strong shielding effect for realizing the lateral deposition of Zn2+ ions along the Zn surface and isolating water from Zn metal to effectively inhibit side reactions. Consequently, the Zn||Zn symmetric cell with the addition of 1.5 mm Rb2 SO4 can cycle more than 6000 h at 0.5 mA cm-2 /0.25 mAh cm-2 , which is 20 times longer than that without Rb2 SO4 . Besides, the Zn||Cu asymmetric cell with Rb2 SO4 achieves a very high average Coulombic efficiency of 99.16% up to 500 cycles. Moreover, the electrolyte with Rb2 SO4 well matches with the VO2 cathode, achieving high initial capacity of 412.7 mAh g-1 at 5 A g-1 and excellent cycling stability with a capacity retention of 71.6% at 5 A g-1 after 500 cycles for the Zn//VO2 full cell.