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According to the latest evidence, the microbial metabolite Urolithin A (UA), known for its role in promoting cellular health, modulates CD8+ T cell-mediated antitumor activity. However, the direct target protein of UA and its underlying mechanism remains unclear. Here, this research identifies ERK1/2 as the specific target crucial for UA-mediated CD8+ T cell activation. Even at low doses, UA markedly enhances the persistence and effector functions of primary CD8+ cytotoxic T lymphocytes (CTLs) and human chimeric antigen receptor (CAR) T cells both in vitro and in vivo. Mechanistically, UA interacts directly with ERK1/2 kinases, enhancing their activation and subsequently facilitating T cell activation by engaging ULK1. The UA-ERK1/2-ULK1 axis promotes autophagic flux in CD8+ CTLs, enhancing cellular metabolism and maintaining reactive oxygen species (ROS) levels, as evidenced by increased oxygen consumption and extracellular acidification rates. UA-treated CD8+ CTLs also display elevated ATP levels and enhanced spare respiratory capacity. Overall, UA activates ERK1/2, inducing autophagy and metabolic adaptation, showcasing its potential in tumor immunotherapy and interventions for diseases involving ERKs.
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Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Linfócitos T CD8-Positivos , Cumarínicos , Animais , Humanos , Camundongos , Autofagia/imunologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/efeitos dos fármacos , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Cumarínicos/farmacologia , Cumarínicos/metabolismo , Modelos Animais de Doenças , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/metabolismoRESUMO
Potassium-ion battery is rich in resources and cheap in price, in the era of lithium-ion battery commercialization, potassium-ion battery is the most likely to replace it. Based on the classification and summary of electrode materials for potassium-ion batteries, this paper focuses on the introduction of manganese-based oxide KxMnO2. The layered KxMnO2 has a large layer spacing and can be embedded with large size potassium-ions. This paper focuses on the preparation and doping of manganese-based cathode materials for potassium-ion batteries, summarizes the main challenges of KxMnO2-based cathode materials in the current stage of research and further looks into its future development direction.
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Objective: To determine sex differences in the prevalence of depression and assess the risk factors for depression among adult patients with epilepsy from the Dali area of China. Methods: We retrospectively analyzed the clinical data of adult patients with epilepsy who visited the First Affiliated Hospital of Dali University from January 2017 to January 2022. Patient Health Questionnaire-9 was used to assess depressive symptoms in patients with epilepsy. The risk factors of depression were analyzed by binary logistic regression among different sex in patients with epilepsy. Results: There were significant sex differences in depression in patients with epilepsy (p < 0.001), and females were 4.27 times more likely to suffer from depression than males (95% confidence interval: 3.70-4.92). The risk factors for depression among female patients with epilepsy included occupation (p < 0.001), years with epilepsy (p < 0.001), seizure frequency (p < 0.001), seizure type (p < 0.001), etiology (p < 0.001), number of antiseizure medications used (p < 0.001), antiseizure medications (p < 0.001), and electroencephalogram findings (p < 0.001). The risk factors for depression among male patients with epilepsy included age (p < 0.001), ethnicity (p < 0.001), occupation (p < 0.001), years with epilepsy (p < 0.001), seizure frequency (p < 0.001), seizure type (p < 0.001), etiology (p < 0.001), number of antiseizure medications used (p < 0.001), antiseizure medications (p < 0.001), and electroencephalogram findings (p < 0.001). Conclusion: Adult female patients with epilepsy had a higher risk of depression than adult male patients with epilepsy. There were sex differences in the risk factors associated with depression among patients with epilepsy.
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T cell immunoglobulin and mucin-containing molecule 3 (Tim-3), expressed in dysfunctional and exhausted T cells, has been widely acknowledged as a promising immune checkpoint target for tumor immunotherapy. Here, using a strategy combining virtual and functional screening, we identified a compound named ML-T7 that targets the FG-CC' cleft of Tim-3, a highly conserved binding site of phosphatidylserine (PtdSer) and carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1). ML-T7 enhanced the survival and antitumor activity of primary CD8+ cytotoxic T lymphocytes (CTLs) and human chimeric antigen receptor (CAR) T cells and reduced their exhaustion in vitro and in vivo. In addition, ML-T7 promoted NK cells' killing activity and DC antigen-presenting capacity, consistent with the reported activity of Tim-3. ML-T7 strengthened DCs' functions through both Tim-3 and Tim-4, which is consistent with the fact that Tim-4 contains a similar FG-CC' loop. Intraperitoneal dosing of ML-T7 showed comparable tumor inhibitory effects to the Tim-3 blocking antibody. ML-T7 reduced syngeneic tumor progression in both wild-type and Tim-3 humanized mice and alleviated the immunosuppressive microenvironment. Furthermore, combined ML-T7 and anti-PD-1 therapy had greater therapeutic efficacy than monotherapy in mice, supporting further development of ML-T7 for tumor immunotherapy. Our study demonstrates a potential small molecule for selectively blocking Tim-3 and warrants further study.
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Receptor Celular 2 do Vírus da Hepatite A , Neoplasias , Humanos , Animais , Camundongos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Linfócitos T CD8-Positivos , Linfócitos T Citotóxicos/metabolismo , Neoplasias/terapia , Imunoterapia , Microambiente TumoralRESUMO
CCAAT/enhancer binding protein α (C/EBPα) regulates myeloid differentiation, and its dysregulation contributes to acute myeloid leukaemia (AML) progress. Clarifying its functional implementation mechanism is of great significance for its further clinical application. Here, we show that C/EBPα regulates AML cell differentiation through liquid-liquid phase separation (LLPS), which can be disrupted by C/EBPα-p30. Considering that C/EBPα-p30 inhibits the functions of C/EBPα through the LZ region, a small peptide TAT-LZ that could instantaneously interfere with the homodimerization of C/EBPα-p42 was constructed, and dynamic inhibition of C/EBPα phase separation was observed, demonstrating the importance of C/EBPα-p42 homodimers for its LLPS. Mechanistically, homodimerization of C/EBPα-p42 mediated its phosphorylation at the novel phosphorylation site S16, which promoted LLPS and subsequent AML cell differentiation. Finally, decreasing the endogenous C/EBPα-p30/C/EBPα-p42 ratio rescued the phase separation of C/EBPα in AML cells, which provided a new insight for the treatment of the AML.
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Proteína alfa Estimuladora de Ligação a CCAAT , Leucemia Mieloide Aguda , Humanos , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Diferenciação Celular , Hematopoese , Leucemia Mieloide Aguda/metabolismo , FosforilaçãoRESUMO
Objective: Alzheimer's disease (AD), a prevalent neurodegenerative affliction that predominantly affects the elderly population, imposes a substantial burden on not only patients but also their families and society at large. Mitochondrial dysfunction plays an important role in its pathogenesis. In this study, we conducted a bibliometric analysis of research on mitochondrial dysfunction and AD over the past 10 years, with the aim of summarizing current research hotspots and trends in this field. Methods: On February 12, 2023, we searched for publications about mitochondrial dysfunction and AD in the Web of Science Core Collection database from 2013 to 2022. VOSview software, CiteSpace, SCImago, and RStudio were used to analyze and visualize countries, institutions, journals, keywords, and references. Results: The number of publications on mitochondrial dysfunction and AD were on the rise until 2021 and decreased slightly in 2022. The United States ranks first in the number of publications, H-index, and intensity of international cooperation in this research. In terms of institutions, Texas Tech University in the United States has the most publications. The Journal of Alzheimer's Disease has the most publications in this field of research, while Oxidative Medicine and Cellular Longevity have the highest number of citations. Mitochondrial dysfunction is still an important direction of current research. Autophagy, mitochondrial autophagy, and neuroinflammation are new hotspots. The article from Lin MT is the most cited by analyzing references. Conclusion: Research on mitochondrial dysfunction in AD is gaining significant momentum as it provides a crucial research avenue for the treatment of this debilitating condition. This study sheds light on the present research trajectory concerning the molecular mechanisms underlying mitochondrial dysfunction in AD.
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Plastic has been demonstrated to release nanoplastics (NPs) into the atmosphere under sunlight irradiation, posing a continuous health risk to the respiratory system. However, due to lack of reliable quantification methods, the occurrence and distribution of NPs in the atmosphere remain unclear. Polystyrene (PS) micro- and nanoplastics (MNPs) represent a crucial component of atmospheric MNPs. In this study, we proposed a simple and robust method for determining the concentration of atmospheric PS NPs using pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). Following active sampling, the filter membrane is directly ground and introduced into the Py-GC/MS system to quantify PS NPs. The proposed method demonstrates excellent reproducibility and high sensitivity, with a detection limit as low as down to 15 pg/m3 for PS NPs. By using this method, the occurrence of PS NPs in both indoor and outdoor atmospheres has been confirmed. Furthermore, the results showed that the abundance of outdoor PS NPs was significantly higher than that of indoor samples, and there was no significant difference in NP vertical distribution within a height of 28.6 m. This method can be applied for the routine monitoring of atmospheric PS NPs and for evaluating their risk to human health.
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Nanopartículas , Poluentes Químicos da Água , Humanos , Poliestirenos , Microplásticos , Cromatografia Gasosa-Espectrometria de Massas , Pirólise , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Nanopartículas/químicaRESUMO
BACKGROUND: The optimum prophylactic regimen against hepatitis B virus (HBV) recurrence after liver transplantation (LT) in HBV-infected patients is uncertain but of great clinical relevance. New evidence suggests that hepatitis B immunoglobulin (HBIG)-free approach would become a reasonable choice in the era of high-potency nucleos(t)ide analogues (HPNAs). We aimed to provide robust estimates for long-term survival and HBV recurrence in patients receiving different HBV-prophylaxis strategies after LT. METHODS: We did a systematic review and meta-analysis using both pseudo-individual patient data recovered from included studies (IPDMA) and conventional trial-level aggregate data meta-analysis (ADMA). Hazard ratios (HRs) were calculated using different Cox proportional hazard models accounting for inter-study heterogeneity. ADMA was conducted to pool outcomes at specific time points. RESULTS: A total of 16 studies involving 7897 patients and 41 studies involving 9435 were eligible for IPDMA and AMDA, respectively. Cumulative HBV recurrence rate and overall survival (OS) at 1, 3, 5 and 10 years post-LT were 0.3%, 0.9%, 1.2%, 1.7% and 95.6%, 89%, 86.4%, 86.4% in the HPNAs (i.e., entecavir and tenofovir) + HBIG combination group vs. 0.6%, 0.6%, 1.2%, 1.7% and 94.5%, 86.8%, 84.8%, 81.2% in the HPNAs monotherapy group (HR 1.20, 95% CI 0.56-2.60, p = 0.64; HR 1.09, 95% CI 0.70-1.69, p = 0.72), respectively. The results were compatible with AMDA. CONCLUSION: A similar HBV recurrence and overall survival were found in patients who used HPNAs (mainly entecavir) monotherapy as in those who received a combination of HPNAs and HBIG. These findings address concerns regarding the safety and effectiveness of HPNAs monotherapy.
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Hepatite B , Transplante de Fígado , Humanos , Vírus da Hepatite B , Antivirais/uso terapêutico , Hepatite B/tratamento farmacológico , Resultado do Tratamento , Imunoglobulinas/uso terapêutico , Quimioterapia Combinada , RecidivaRESUMO
Objective:To analyze the expression of targeting protein for Xklp2 (TPX2) in kidney renal clear cell carcinoma (KIRC) and its clinical significance.Methods:The postoperative tissue samples of 54 patients with KIRC admitted to the Department of Urology, the First Affiliated Hospital of Bengbu Medical College from July 2017 to June 2019 were collected. Immunohistochemistry was used to detect the protein expression of TPX2 in renal carcinoma and paracancerous tissues. The difference of TPX2 mRNA expression between KIRC tissues and normal tissues was analyzed by using the TIMER database, which verified the immunohistochemical results. The UALCAN database and the Kaplan-Meier plotter database were used to analyze the relationship between TPX2 mRNA expression and clinical stage, molecular subtypes, lymph node metastasis, and prognosis of patients with KIRC. The protein interaction network was constructed by STRING database to obtain TPX2-related proteins, and the genes corresponding to the related proteins were enriched for the KEGG pathway. The relationship between TPX2 expression and immune cell infiltration and the immune checkpoint was studied by using the TIMER database.Results:Immunohistochemical results showed that the positive expression rate of TPX2 protein was 48.15% (26/54) in cancer tissues, which was higher than that in paracancerous tissues (20.37%, 11/54) ( χ2=9.25, P=0.002). The results of bioinformatics analysis showed that TPX2 mRNA expression was significantly up-regulated in KIRC [cancer tissue: 1.89 (1.49, 2.42), normal tissue: 0.35 (0.24, 0.57), U=2 297.00, P<0.001]. The expression of TPX2 mRNA was related to the clinical stage ( χ2=34.36, P<0.001), molecular subtypes ( χ2=30.15, P<0.001), and lymph node metastasis status ( χ2=27.21, P<0.001) of KIRC patients. The 5-year survival rate (53.80%) in patients with high TPX2 expression was lower than that in patients with low TPX2 expression (74.40%, χ2=18.87, P<0.001). STRING database protein interaction network construction obtained 20 TPX2-related proteins, and the genes corresponding to the related proteins were enriched in the cell cycle. The expression of TPX2 was positively correlated with B cells ( r=0.30, P<0.001), CD8 + T cells ( r=0.23, P<0.001), CD4 + T cells ( r=0.18, P<0.001), macrophages ( r=0.20, P<0.001), neutrophils ( r=0.31, P<0.001), dendritic cells ( r=0.39, P<0.001) infiltration and most of its biomarkers (all P<0.05). It was positively correlated with immune checkpoint PD-1 ( r=0.31, P<0.001) and CTLA-4 ( r=0.27, P<0.001), but not correlated with PD-L1 ( r=0.07, P=0.146) . Conclusion:TPX2 is highly expressed in KIRC and is closely associated with poor prognosis. It is expected to be a new therapeutic target for KIRC.
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Multiple primary malignancies (MPMs) are two or more primary malignancies diagnosed in the same patient at the same time or at a specific time and do not represent progression, recurrence or metastasis of the first tumor.MPMs are extremely rare. In this paper, we reported a case of male patient who was diagnosed with invasive uroepithelial carcinoma, rectal adenocarcinoma, clear cell renal cell carcinoma and sarcomatoid carcinoma of the bladder, and open partial cystectomy, laparoscopic radical operation for rectal cancer, laparoscopic partial left nephrectomy, transurethral resection of bladder tumor and laparoscopic radical cystectomy with ureterostomy were performed, respectively.The patient was followed up for 16 months after the last surgery, with good general condition and no recurrence or metastasis.
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BACKGROUND: The effects of consolidation chemotherapy (CC) in neoadjuvant therapy in locally advanced rectal cancer (LARC) have been explored. However, the optimal neoadjuvant chemoradiotherapy (NCRT) and surgery interval, regimen, and cycles of chemotherapy remains unclear. AIM: To evaluate the effects of one to two cycles of CC with capecitabine on high-risk patients with LARC without extending NCRT and surgery interval. METHODS: We retrospectively evaluated high-risk patients with LARC, who were defined as having at least one of the following factors by magnetic resonance imaging: depth of invasion beyond the muscularis propria of more than 5 mm (cT3c-cT3d), T4, meso-rectal fascia or extramural vascular invasion positive, and treatment date between January 2015 and July 2019 in our center. Patients were divided into the CC and non-CC group according to whether they received CC (capecitabine 1000 mg/m2 twice daily from days 1 to 14 every 21 d) after NCRT. Propensity score matching (PSM) and inverse probability of treatment weight (IPTW) were used to balance the differences between the two groups. The main outcome was the complete response (CR) rate. RESULTS: A total of 265 patients were enrolled: 136 patients in the CC group and 129 patients in the non-CC group. The median interval was 70 d (range, 37-168). The CR rate was 24.3% and 16.3% (P = 0.107) in the CC and non-CC groups' original samples, respectively. After PSM and IPTW, the CR rate in the CC group was higher than that in non-CC group (27.6% vs 16.2%, P = 0.045; 25.9% vs 16.3%, P = 0.045). The median follow-up was 39.8 mo (range, 2.9-74.8), and there were no differences in 3-year non-regrowth disease-free survival nor overall survival in the original samples (73.2% vs 71.9%, P = 0.913; 92.3% vs 86.7%, P = 0.294), PSM (73.2% vs 73.5%, P = 0.865; 92.5% vs 89.3%, P = 0.612), and IPTW (73.8% vs 72.1%, P = 0.913; 92.4% vs 87.4%, P = 0.294). There was also no difference in grade 2 or higher acute toxicity during neoadjuvant therapy in the two groups (49.3% vs 53.5%, P = 0.492). CONCLUSION: One to two cycles of CC with capecitabine after NCRT was safe and increased the CR rate in high-risk LARC but failed to improve the long-term outcomes.
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Aims: To compare the effectiveness of cervical epidural injections of local anesthetic with vs. without a steroid. Methods: Three databases (PubMed, Embase, and Cochrane library) were used to search and assess all clinical randomized controlled trials regarding the clinical efficacy of epidural injections from January 01, 2009, to October 31, 2020. Cochrane review criteria and the Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment instrument were used to evaluate the methodologic quality of the included studies. Qualitative and quantitative analyses were performed according to best evidence synthesis principles and by single-arm meta-analysis, respectively. Results: Based on the search criteria, 4 RCTs were qualitatively and quantitatively analyzed in the single-arm meta-analysis. Treatment with lidocaine alone or with the steroid resulted in decreases of 4.46 and 4.29 points, respectively, in pain scores and of 15.8 and 14.46 points, respectively, in functional scores at 6 months. Similar trends were observed at the 1-year follow-up: pain scores decreased by 4.27 and 4.14 points, while functional scores decreased by 15.94 and 14.44 points in patients with neck pain who received lidocaine without or with the steroid, respectively. In the 3 studies that reported 2-year follow-up data, patients with neck pain treated with lidocaine or lidocaine + steroid showed 4.2- and 4.14-point decreases, in pain score and 15.92- and 14.89-point decreases, respectively, in functional scores. Conclusions: The studies showed level I (strong) evidence for short- and long-term improvements in pain relief and functionality with cervical epidural injections of local anesthetic alone or with a steroid in the management of neck pain.
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Anestésicos Locais , Cervicalgia , Anestésicos Locais/uso terapêutico , Humanos , Injeções Epidurais/métodos , Lidocaína/uso terapêutico , Cervicalgia/tratamento farmacológico , Reprodutibilidade dos Testes , Esteroides/uso terapêutico , Resultado do TratamentoRESUMO
In thermal deformation of materials, grain refinement induced by dynamic recrystallization (DRX) is often pursued to obtain excellent mechanical properties. Here, the thermal deformation behaviors of SAE 5137H steel were investigated and characterized at temperature and strain rate range of 1123-1483 K and 0.01-10 s-1. Meanwhile, a design approach in speed-loading paths for grain refinement during current-heating compression was proposed, and these paths are linked to a typical three-dimensional (3D) response surface. Depending on the acquired stress-strain curves, the flow behaviors of this steel were analyzed and the typical 3D processing map was constructed to clarify the stable processing parameter domains during the continuous deformation process. Then, by the typical 3D processing map and microstructure observation, the 3D deformation mechanism map was constructed to connect the processing parameters and microstructural mechanisms. Subsequently, the 3D activation energy map was constructed to evaluate these deformation mechanisms, and the enhanced deformation mechanism map was constructed. Eventually, based on the enhanced deformation mechanism map, the speed-loading paths for SAE 5137H steel during current-heating compression were designed and they are mapped in a 3D response surface.
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BACKGROUND: Studies have found that α-mangostin (MG) can relieve experimental arthritis by activating cholinergic anti-inflammatory pathway (CAP). It affects the polarization of macrophages and the balance of related immune cell subpopulations, but the specific mechanism is still unclear. It has been found that silent information regulator 1 (SIRT1) is closely related to macrophage activity. The purpose of this study is to explore the mechanism of MG intervening in macrophage polarization during treatment of early adjuvant-induced (AIA) rats through the CAP-SIRT1 pathway. METHODS: We investigated the polarization of M1 macrophages and the differentiation of Th1 in AIA rats by flow cytometry. Activity of acetylcholinesterase (AChE) and the level of nicotinic adenine dinucleotide (NAD+) in serum were also detected, and immunohistochemical was used to detect the levels of α7 nicotinic cholinergic receptor (α7nAChR) and SIRT1. Then in macrophages, the molecular mechanism of MG regulating the abnormal activation of macrophages in rats with early AIA through the CAP-SIRT1 pathway was studied. RESULTS: MG can significantly inhibit the polarization of M1 macrophages and the differentiation of Th1 in AIA rats in the acute phase of inflammation. MG can significantly inhibit the activity of AChE and increase the level of NAD+, thereby further up-regulated the expression levels of α7nAChR and SIRT1. Meanwhile, MG inhibited nuclear factor-κB (NF-κB)-mediated inflammation by activating the CAP-SIRT1 pathway in macrophages. CONCLUSION: In summary, the stimulation of MG induced CAP activation, which up-regulated SIRT1 signal, and thereby inhibited M1 polarization through the NF-κB pathway, and improved the pathological immune environment of early-stage AIA rats.
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Artrite Experimental , Sirtuína 1 , Acetilcolinesterase/metabolismo , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Macrófagos/metabolismo , NF-kappa B/metabolismo , Ratos , Sirtuína 1/metabolismo , XantonasRESUMO
The emergence of antibiotic resistant bacteria represents a significant and common clinical problem worldwide as infections are becoming increasingly common. It is urgent to broaden the sources of biomaterials that can prevent both bacterial infection and antibiotic resistance. In this work, oxidized sodium alginate/aminated hyaluronic acid (OSA/AHA) hydrogel with various proportions was developed based on Schiff base reaction. Herein, polydopamine (PDA)-Bmkn2 nanoparticle and sanguinarine were incorporated into hydrogels to enhance antibacterial properties. The prepared PDA-Bmkn2 nanoparticles, with uniform particle size and good dispersion, could serve as a delivery system for Bmkn2. The prepared hydrogels showed appropriate swelling ratio, extremely good mechanical strengths and improved biodegradability. Meanwhile, the Bmkn2 and sanguinarine were released from the hydrogels in a sustainable manner. Furthermore, OSA/AHA/sanguinarine/PDA-Bmkn2 hydrogel (less than 10 µg/mL BmKn2 and 0.2 µg/mL sanguinarine) had excellent biocompatibility. Antibacterial experiments confirmed that OSA/AHA/sanguinarine/PDA-Bmkn2 hydrogel had effective antimicrobial activity on Escherichia coli and Staphylococcus aureus. Therefore, the prepared injectable hydrogels with good biocompatibility and excellent synergistic antibacterial activity promise great potential for preventing localized bacterial infections.
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In order to obtain the desired mechanical properties of products, an innovative method of loading parameter designs for acquiring the desired grain refinement is proposed, and it has been applied in the compression process of Ni80A superalloy. The deformation mechanism maps derived from processing maps based on the Dynamic Materials Model (DMM) theory were constructed, since the critical indicator values corresponding to dynamic recrystallization (DRX) and dynamic recovery (DRV) mechanisms were determined. The processing-parameter domains with DRX mechanisms were separated from the deformation mechanism map, while such domains were chaotic and difficult to apply in innovative parameter loading path design. The speed-loading path derived from strain rate-loading path in a compression process was pursued. The grain refinement domains are discretized into a finite series of sub-domains with clear processing parameters, and the optimal strain rate of each sub-domain is determined by step-by-step finite element simulation. A 3D response surface of the innovative optimal loading path of strain rate was fitted by interpolating methods. Finally, the isothermal compression experiments for Ni80A superalloy were conducted, and the microstructure observations indicated that the desired grain refinement was achieved. This innovative method of parameter loading path design contributes to the microstructure adjustment of the alloys with DRX mechanism.
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Electrode materials with high conductivities that are compatible with flexible substrates are important for preparing high-capacitance electrode materials and improving the energy density of flexible supercapacitors. Here, we report the design and fabrication of a new type of flexible electrode based on nanosheet architectures of a Co-Fe alloy (FeCo-A) coated with ternary metal sulfide composites (FeCo-Ss) on silver-sputtered carbon cloth. The high conductivity of the flexible substrate and the iron-cobalt alloy skeleton enables good electron transmission through the material. In particular, the outer FeCo-S layer has an average thickness of â¼30 nm, providing many active sites. This layer also inhibits the oxidation of the alloy. The electrode material is close to 20 nm thick, which limits inaccessible volumes and promotes high utilization of FeCo-alloy@FeCo-sulfide (FeCo-A-S). The additive-free FeCo-A-S electrode has a high specific capacitance of 2932.2 F g-1 at 1.0 A g-1 and a superior rate capability. All-solid-state supercapacitors based on these electrodes have a high power density of 8000 W kg-1 and a high energy density of 46.1 W h kg-1.
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Thanks to their high conductivity and theoretical capacity, transition metal selenides have demanded significant research attention as prospective anodes for sodium-ion batteries. Nevertheless, their practical applications are hindered by finite cycle life and inferior rate performance because of large volume expansion, polyselenide dissolution, and sluggish dynamics. Herein, the nitrogen-doped carbon (NC)-coated FeSe2 nanoparticles encapsulated in NC nanoboxes (termed FeSe2@NDC NBs) are fabricated through the facile thermal selenization of polydopamine-wrapped Prussian blue precursors. In this composite, the existing nitrogen-doped dual carbon layer improves the intrinsic conductivity and structural integrity, while the unique porous yolk-shell architecture significantly mitigates the volume swelling during the sodium/desodium process. Moreover, the derived Fe-N-C bonds can effectively capture polyselenide, as well as promote Na+ transportation and good reversible conversion reaction. As expected, the FeSe2@NDC NBs deliver remarkable rate performance (374.9 mA h g-1 at 10.0 A g-1) and long-cycling stability (403.3 mA h g-1 over 2000 loops at 5.0 A g-1). When further coupled with a self-made Na3V2(PO4)3@C cathode in sodium-ion full cells, FeSe2@NDC NBs also exhibit considerably high and stable sodium-storage performance.
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Transition-metal selenides (TMSs) have emerged as prospective anode materials for sodium ion batteries (SIBs), owing to their considerable theoretical capacity and intrinsic high electronic conductivity. Whereas, TMSs still suffer from poor rate capability and inferior cycling stability induced by sluggish kinetics and severe volume changes during de/sodiation processes. Herein, a hierarchical composite consisting of a zinc-cobalt bimetallic selenide yolk and nitrogen-doped double carbon shell (denoted as ZnCoSe@NDC) is engineered and fabricated successfully. The architecture of the as-fabricated material improves the Na-ion storage performance via increasing the electron transfer kinetics, accommodating volume expansion, and mitigating the generation of by-products. As expected, the ZnCoSe@NDC electrode delivers superior sodium storage performance with long cycling stability (344.5 mAh g-1 at 5.0 A g-1 over 2000 long-term cycles) and high-rate performance (319.2 mAh g-1 at 10.0 A g-1 ). Meanwhile, the NVP@C//ZnCoSe@NDC full SIB cells are constructed successfully, retaining 96.3% of its initial capacity at 0.5A g-1 after 200 loops. The outstanding electrochemical performance and the construction of hybrid SIBs will have far-reaching influences on the development of the various rechargeable batteries.