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Layered transition metal oxides are promising cathode materials for sodium-ion batteries due to their high energy density and appropriate operating potential. However, the poor structural stability is a major drawback to their widespread application. To address this issue, B3+ is successfully introduced into the tetrahedral site of Na0.67 Fe0.5 Mn0.5 O2 , demonstrating the effectiveness of small-radius ion doping in improving electrochemical performance. The obtained Na0.67 Fe0.5 Mn0.5 B0.04 O2 exhibits excellent cycling performance with 88.8% capacity retention after 100 cycles at 1 C and prominent rate performance. The structure-property relationship is constructed subsequently by neutron powder diffraction, in situ X-ray diffraction and X-ray absorption spectroscopy, which reveal that the Jahn-Teller distortion and the consequent P2-P2' phase transformation are effectively mitigated because of the occupancy of B3+ at the interstitial site. Furthermore, it is found that the transition metal layers are stabilized and the transition metal dissolution are suppressed, resulting in excellent cycling performance. Besides, the prominent rate performance is attributed to the enhanced diffusion kinetics associated with the rearrangement of Na+ . This work provides novel insight into the action mechanism of interstitial site doping and demonstrates a universal approach to improve the electrochemical properties of P2-type manganese-based sodium cathode materials.
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BACKGROUND: Vascular embolism is a serious complication of hyaluronic acid (HA) filler cosmetic injection, and hyaluronidase injection has been proposed as the treatment. Until now, there has been a lack of adequate clinical evidence regarding the benefits of treatment for HA filler-induced vascular embolism by percutaneous facial or supratrochlear arterial hyaluronidase injection. OBJECTIVES: The authors sough to evaluate the efficacy of percutaneous facial or supratrochlear arterial hyaluronidase injection as a rescue treatment for HA filler-induced vascular embolism. METHODS: We included 17 patients with vascular embolism after facial HA filler injection. Intraarterial injection of 1500 units hyaluronidase was performed via facial artery for 13 cases with skin necrosis and via supratrochlear arterial for 4 cases with severe ptosis and skin necrosis but no visual impairment. Simultaneously, general symptomatic treatment and nutritional therapy were performed. RESULTS: After hyaluronidase injection, facial skin necrosis in all cases was restored and ptosis in the 4 cases was also significantly relieved. Patients were subsequently followed-up for 1 month to 1 year. The skin necrosis in 16 patients completely healed, and only 1 patient had small superficial scars. CONCLUSIONS: It is effective to alleviate skin necrosis and ptosis resulting from HA filler embolism via percutaneous facial or supratrochlear arterial hyaluronidase injection.
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Técnicas Cosméticas , Preenchedores Dérmicos , Embolia , Artérias , Técnicas Cosméticas/efeitos adversos , Embolia/tratamento farmacológico , Embolia/etiologia , Humanos , Ácido Hialurônico , Hialuronoglucosaminidase , Injeções Intra-Arteriais , NecroseRESUMO
BACKGROUND: Most NSCLCs metastasised out of the lungs at the time of diagnosis and cannot be surgically removed . Cytotoxic chemotherapy drugs have become the main treatment in recent decades, especially in patients with NSCLC without EGFR, ALK, and ROS gene mutations. The prognosis of lung cancer is poor, and the overall 5-year survival rate is only 9-13%. Therefore the treatment of advanced NSCLC remains a significant medical need. Recent studies have shown a significant relationship between the gut-lung axis microecology and malignant tumors. Intestinal probiotics are likely to play a role in inhibiting tumorigenesis through "intestinal-pulmonary axis microecological regulation". This study will seek to investigate the efficacy of "Microbiota modulation of the Gut-Lung Axis" combined with chemotherapy in patients with advanced NSCLC. METHODS: The research is a multicenter, prospective, double blind, placebo controlled, randomized trial. Based on the theoretical basis of "intestinal and lung axis microecological adjustment", combined with traditional platinum-containing two-drug chemotherapy, the efficacy of the new therapy on patients with advanced NSCLC was observed. Collect the basic information of the patient, and study the effect of platinum-based combined chemotherapy on the diversity of intestinal flora in patients with lung cancer after receiving chemotherapy treatment, feces before and after chemotherapy, and the status and extent of adverse reactions during chemotherapy . A total of 180 subjects were included, divided into a control group (platinum-containing dual-drug chemotherapy) and an intervention group (platinum-containing dual-drug chemotherapy combined with Bifico), and were randomly assigned to the group 1:1. DISCUSSION: As a result, intestinal-pulmonary microecological balance could become a new target for the treatment of lung cancer. This study explores the combination of intestinal microecological regulation and chemotherapy to provide new treatment strategies and basis for lung cancer patients. It can help prolong the survival time of lung cancer patients and improve the quality of life, thereby generating huge economic and social benefits. The results can be promoted and applied to units engaged in the treatment of lung cancer. TRIAL REGISTRATION NUMBER: NCT03642548, date: August 22, 2018, the first version protocol. The URL of trial registry record: https://clinicaltrials.gov/ct2/show/NCT03642548?term=NCT03642548&draw=2&rank=1 .
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Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Microbioma Gastrointestinal/genética , Neoplasias Pulmonares/tratamento farmacológico , Adolescente , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Método Duplo-Cego , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto JovemRESUMO
Recently, the morbidity and mortality from lung cancer have continued to increase. Mitochondrial dysfunction plays a key role in apoptosis, proliferation, and the bioenergetic reprogramming of cancer cells, especially for energy metabolism. Herein, we investigated the ability of melatonin (MLT) to influence lung cancer growth and explored the association between mitochondrial functions and the progression of lung tumors. The deacetylase, sirtuin 3 (Sirt3), is a pivotal player in maintenance of mitochondrial function, among participating in ATP production by regulating the acetylone and pyruvate dehydrogenase complex (PDH). We initially found that MLT inhibited lung cancer growth in the Lewis mouse model. Similarly, we observed that MLT inhibited the proliferation of lung cancer cells (A549, PC9, and LLC cells), and the underlying mechanism of MLT was related to reprogramming cancer cell metabolism, accompanied by a shift from cytosolic aerobic glycolysis to oxidative phosphorylation (OXPHOS). These changes were accompanied by higher ATP production, an elevated ATP production-coupled oxygen consumption rate (QCR), higher ROS levels, higher mito-ROS levels, and lower lactic acid secretion. Additionally, we observed that MLT improved mitochondrial membrane potential and the activities of complexes â and â £ in the electron transport chain. Importantly, we also found and verified that the foregoing changes resulted from activation of Sirt3 and PDH. As a result of these changes, MLT significantly enhanced mitochondrial energy metabolism to reverse the Warburg effect via increasing PDH activity with stimulation of Sirt3. Collectively, these findings suggest the potential use of melatonin as an anti-lung cancer therapy and provide a mechanistic basis for this proposal.
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Neoplasias Pulmonares , Melatonina , Sirtuína 3 , Animais , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Melatonina/farmacologia , Camundongos , Complexo Piruvato Desidrogenase/metabolismo , Sirtuína 3/metabolismoRESUMO
We fabricated mesoporous perovskite nanocrystal for the first time, and investigated its optical properties and application in light-emitting diodes (LEDs). The transformation of mesoporous structure can be ascribed to the decomposition of nanocrystals under dilution condition, which results in the blueshift of luminescence. The mesoporous nanocrystals under proper dilution may achieve improved perovskite LEDs, with maximum luminance and current efficiency of 23370 cd m-2and 6.7 cd A-1, respectively. This work provide an avenue to the optical engineering of perovskite nanocrystals, and demonstrate that perovskite concentration is one of key factors for realizing efficient LEDs.
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Luminescent liquid Crystal (LC) material is regarded as the most promising material for polarized organic light emission due to their intrinsic characteristics including orderly alignment and luminescence. Nevertheless, the optical extraction efficiency of LC based organic light emitting diodes (OLEDs) devices still requires significant effort and innovation towards real-world applications. In this paper, we propose the design of a highly linearly polarized light-emission from OLEDs with integrated refractive index nanograting in the emissive layer (EML) based on photo aligned luminescent liquid crystal material. The simulation results indicate that the geometrically optimized polarized device yields an external quantum efficiency (EQE) up to 47% with a polarized ratio up to 28â dB at a 550â nm emission wavelength. This conceptual design offers a new opportunity to achieve efficient polarized organic luminescence, and it is (to the best of our knowledge) the first approach that enhances the light extraction of OLEDs based on luminescent liquid crystal via index grating in the EML.
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Improving the electrical conductivity of sulfur, suppressing shuttle/dissolution of polysulfide, and enhancing reaction kinetics in Li-S batteries are essential for practical applications. Here, for the first time, we have used inexpensive oleic acid as a single carbon source, and have added commercial SiO2 as a template to form a porous structure, whereas introducing Fe(NO3 )3 and Ni(NO3 )2 as catalysts to increase the degree of graphitization. Moreover, the dual metal salts Fe(NO3 )3 and Ni(NO3 )2 can also form FeNi3 alloy, and our results show that FeNi3 nanoparticles accelerate the kinetic conversion reactions of polysulfide. By virtue of the well-developed porous structure and high degree of graphitization, the highly graphitized porous carbon-FeNi3 (GPC-FeNi3 ) has high conductivity to ensure fast charge transfer, and the hierarchically porous structure facilitates ion diffusion and traps polysulfide. Thus, a GPC-FeNi3 /S cathode displays excellent electrochemical performance. At current rates of 0.2 and 1â C, a cathode of the GPC-FeNi3 /S composite with a sulfur content of 70 % delivers high initial discharge capacities of 1108 and 880â mA h g-1 , respectively, and retains reversible specific capacities of 850â mA h g-1 after 200â cycles at 0.2â C and 625â mA h g-1 after 400â cycles at 1â C.
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Co-amplification at lower denaturation temperature-polymerase chain reaction (COLD-PCR) is a novel form of PCR that selectively denatures and amplifies low-abundance mutations from mixtures of wild-type and mutation-containing sequences, enriching the mutation 10 to 100 folds. Due to the slightly altered melting temperature (Tm) of the double-stranded DNA and the formation of the mutation/wild-type heteroduplex DNA, COLD-PCR methods are sensitive, specific, accurate, cost-effective and easy to maneuver, and can enrich mutations of any type and at any position, even unknown mutations within amplicons. COLD-PCR and its improved methods are now applied in cancer, microorganisms, prenatal screening, animals and plants. They are extremely useful for early diagnosis, monitoring the prognosis of disease and the efficiency of the treatment, drug selection, prediction of prognosis, plant breeding and etc. In this review, we introduce the principles, key techniques, derived methods and applications of COLD-PCR.
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Reação em Cadeia da Polimerase/métodos , Animais , Análise Mutacional de DNA , Humanos , Reação em Cadeia da Polimerase/instrumentação , Reação em Cadeia da Polimerase/tendências , TemperaturaRESUMO
Introduction: Fused in sarcoma (FUS) mutations represent the most common genetic etiology of juvenile amyotrophic lateral sclerosis (JALS), for which effective treatments are lacking. In a prior report, we identified a novel FUS mutation, c.1509dupA: p. R503fs (FUSR503fs), in a sporadic JALS patient. Methods: The physicochemical properties and structure of FUSR503fs protein were analyzed by software: Multi-electrode array (MEA) assay, calcium activity imaging assay and transcriptome analysis were used to explore the pathophysiological mechanism of iPSC derived motor neurons. Results: Structural analysis and predictions regarding physical and chemical properties of this mutation suggest that the reduction of phosphorylation and glycosylation sites, along with alterations in the amino acid sequence, may contribute to abnormal FUS accumulation within the cytoplasm and nucleus of induced pluripotent stem cell- derived motor neurons (MNs). Multi-electrode array and calcium activity imaging indicate diminished spontaneous electrical and calcium activity signals in MNs harboring the FUSR503fs mutation. Transcriptomic analysis reveals upregulation of genes associated with viral infection and downregulation of genes involved in neural function maintenance, such as the ATP6V1C2 gene. Treatment with ropinirole marginally mitigates the electrophysiological decline in FUSR503fs MNs, suggesting the utility of this cell model for mechanistic exploration and drug screening. Discussion: iPSCs-derived motor neurons from JALS patients are promising tools for drug screening. The pathological changes in motor neurons of FUSR503fs may occur earlier than in other known mutation types that have been reported.
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Purpose: This study aimed to construct targeting drug-loading nanocomposites (FA-FePt/DDP nanoliposomes) to explore their potential in ovarian cancer therapy and molecular magnetic resonance imaging (MMRI). Methods: FA-FePt-NPs were prepared by coupling folate (FA) with polyethylene-glycol (PEG)-coated ferroplatinum nanoparticles and characterized. Then cisplatin (DDP) was encapsulated in FA-FePt-NPs to synthesize FA-PEG-FePt/DDP nanoliposomes by thin film-ultrasonic method and high-speed stirring, of which MMRI potential, magnetothermal effect, and the other involved performance were analyzed. The therapeutic effect of FA-FePt/DDP nanoliposomes combined with magnetic fluid hyperthermia (MFH) on ovarian cancer in vitro and in vivo was evaluated. The expression levels of Bax and epithelial-mesenchymal transition related proteins were detected. The biosafety was also preliminarily observed. Results: The average diameter of FA-FePt-NPs was about 30 nm, FA-FePt/DDP nanoliposomes were about 70 nm in hydrated particle size, with drug slow-release and good cell-specific targeted uptake. In an alternating magnetic field (AMF), FA-FePt/DDP nanoliposomes could rapidly reach the ideal tumor hyperthermia temperature (42~44 °C). MRI scan showed that FA-FePt-NPs and FA-FePt/DDP nanoliposomes both could suppress the T2 signal, indicating a good potential for MMRI. The in vitro and in vivo experiments showed that FA-FePt/DDP-NPs in AMF could effectively inhibit the growth of ovarian cancer by inhibiting cancer cell proliferation, invasion, and migration, and inducing cancer cell apoptosis, much better than that of the other individual therapies; molecularly, E-cadherin and Bax proteins in ovarian cancer cells and tissues were significantly increased, while N-cadherin, Vimentin, and Bcl-2 proteins were inhibited, effectively inhibiting the malignant progression of ovarian cancer. In addition, no significant pathological injury and dysfunction was observed in major visceras. Conclusion: We successfully synthesized FA-FePt/DDP nanoliposomes and confirmed their good thermochemotherapeutic effect in AMF and MMRI potential on ovarian cancer, with no obvious side effects, providing a favorable strategy of integrated targeting therapy and diagnosis for ovarian cancer.
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Antineoplásicos , Cisplatino , Ácido Fólico , Lipossomos , Imageamento por Ressonância Magnética , Neoplasias Ovarianas , Polietilenoglicóis , Feminino , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/terapia , Lipossomos/química , Cisplatino/farmacologia , Cisplatino/química , Cisplatino/administração & dosagem , Cisplatino/farmacocinética , Animais , Ácido Fólico/química , Ácido Fólico/farmacologia , Ácido Fólico/farmacocinética , Humanos , Imageamento por Ressonância Magnética/métodos , Polietilenoglicóis/química , Linhagem Celular Tumoral , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Camundongos , Platina/química , Platina/farmacologia , Hipertermia Induzida/métodos , Nanocompostos/química , Camundongos Nus , Camundongos Endogâmicos BALB C , Nanopartículas Metálicas/química , Campos Magnéticos , Tamanho da PartículaRESUMO
Hepatocellular carcinoma (HCC) is the most common type of liver cancer and is associated with high morbidity and mortality rates. The aims of this study were to investigate the immune-promoting action of nucleolar and spindle-associated protein 1 (NUSAP1) and identify an immunotherapy target for HCC. The Cancer Genome Atlas (TCGA) was used to analyze interaction molecules and immune correlation. The interaction between NUSAP1 and SHC binding and spindle associated 1 (SHCBP1) was examined. The role of the SHCBP1/Janus kinase 2/signal transducer and activator of transcription 3 (SHCBP1/JAK2/STAT3) pathway in this process was explored. After co-culture with HCC cell lines, the differentiation of peripheral blood mononuclear cells (PBMCs) into dendritic cells (DC) was evaluated by measuring the expression of surface factors CD1a and CD86. Pathological tissues from 50 patients with HCC were collected to validate the results of cell experiments. The expression levels of CD1a and CD86 in tissues were also determined. The results show that NUSAP1 interacted with SHCBP1 and was positively correlated with DC. In HCC cell lines, an interaction was observed between NUSAP1 and SHCBP1. It was verified that NUSAP1 inhibited the JAK2/STAT3 phosphorylation pathway by blocking SHCBP1. After co-culture, the levels of CD1a and CD86 in PBMC were elevated. In the clinical specimens, CD1a and CD86 expression levels were significantly higher in the high-NUSAP1 group versus the low-NUSAP1 group. In Summary, NUSAP1 enhanced immunity by inhibiting the SHCBP1/JAK2/STAT3 phosphorylation pathway and promoted DC generation and HCC apoptosis. NUSAP1 may be a target of immunotherapy for HCC.
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Reduced glutathione (GSH) is widely used as an antioxidant in clinical practice, but whether GSH affects the development of early lung cancer remains unclear. Herein, we investigated the mechanism underlying the anticancer effect of GSH in patients with pulmonary nodules. Thirty patients with pulmonary nodules were treated with GSH intravenously for 10 days at a dose of 1.8 g/d, followed by oral administration of the drug at a dose of 0.4 g three times daily for 6 months. The results showed that GSH treatment promoted nodule absorption and reduced the IL-6 level in the peripheral blood of the patients. GSH reduced IL-6 expression in inflammatory BEAS-2B and lung cancer cells and inhibited the proliferation of lung cancer cell lines in vitro. In addition, GSH reduced IL-6 expression by decreasing ROS via down-regulating PI3K/AKT/FoxO pathways. Finally, GSH reversed the Warburg effect, restored mitochondrial function, and reduced the IL-6 expression via PI3K/AKT/FoxO pathways. The in vivo experiment confirmed that GSH inhibited lung cancer growth, improved mitochondrial function, and reduced the IL-6 expression by regulating key enzymes via the PI3K/AKT/FoxO pathway. In conclusion, we uncovered that GSH exerts an unprecedentedly potent anti-cancer effect to prevent the transformation of lung nodules to lung cancer by improving the mitochondrial function and suppressing inflammation via PI3K/AKT/FoxO pathway. This investigation innovatively positions GSH as a potentially safe and efficacious old drug with new uses, inhibiting inflammation and early lung cancer. The use of the drug offers a promising preventive strategy when administered during the early stages of lung cancer.
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The unique 1D crystal structure of Antimony Triselenide (Sb2Se3) offers notable potential for use in flexible, lightweight devices due to its excellent bending characteristics. However, fabricating high-efficiency flexible Sb2Se3 solar cells is challenging, primarily due to the suboptimal contact interface between the embedded Sb2Se3 layer and the molybdenum back-contact, compounded by complex intrinsic defects. This study introduces a novel Molybdenum Trioxide (MoO3) interlayer to address the back contact interface issues in flexible Sb2Se3 devices. Further investigations indicate that incorporating a MoO3 interlayer not only enhances the crystalline quality but also promotes a favorable [hk1] growth orientation in the Sb2Se3 absorber layer. It also reduces the barrier height at the back contact interface and effectively passivates harmful defects. As a result, the flexible Sb2Se3 solar cell, featuring a Mo-foil/Mo/MoO3/Sb2Se3/CdS/ITO/Ag substrate structure, demonstrates exceptional flexibility and durability, enduring large bending radii and multiple bending cycles while achieving an impressive efficiency of 8.23%. This research offers a straightforward approach to enhancing the performance of flexible Sb2Se3 devices, thereby expanding their application scope in the field of photovoltaics.
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Antimony triselenide (Sb2 Se3 ) has possessed excellent optoelectronic properties and has gained interest as a light-harvesting material for photovoltaic technology over the past several years. However, the severe interfacial and bulk recombination obviously contribute to significant carrier transport loss thus leading to the deterioration of power conversion efficiency (PCE). In this work, buried interface and heterojunction engineering are synergistically employed to regulate the film growth kinetic and optimize the band alignment. Through this approach, the orientation of the precursor films is successfully controlled, promoting the preferred orientational growth of the (hk1) of the Sb2 Se3 films. Besides, interfacial trap-assisted nonradiative recombination loss and heterojunction band alignment are successfully minimized and optimized. As a result, the champion device presents a PCE of 9.24% with short-circuit density (JSC ) and fill factor (FF) of 29.47 mA cm-2 and 63.65%, respectively, representing the highest efficiency in sputtered-derived Sb2 Se3 solar cells. This work provides an insightful prescription for fabricating high-quality Sb2 Se3 thin film and enhancing the performance of Sb2 Se3 solar cells.
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Dendritic cells (DCs) are antigen-presenting cells that play a crucial role in initiating immune responses by cross-presenting relevant antigens to initial T cells. The activation of DCs is a crucial step in inducing anti-tumor immunity. Upon recognition and uptake of tumor antigens, activated DCs present these antigens to naive T cells, thereby stimulating T cell-mediated immune responses and enhancing their ability to attack tumors. It is particularly noted that DCs are able to cross-present foreign antigens to major histocompatibility complex class I (MHC-I) molecules, prompting CD8+ T cells to proliferate and differentiate into cytotoxic T cells. In the malignant progression of hepatocellular carcinoma (HCC), the inactivation of DCs plays an important role, and the activation of DCs is particularly important in anti-HCC immunotherapy. In this review, we summarize the mechanisms of DCs activation in HCC, the involved regulatory factors and strategies to activate DCs in HCC immunotherapy. It provides a basis for the study of HCC immunotherapy through DCs activation.
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Carcinoma Hepatocelular , Células Dendríticas , Neoplasias Hepáticas , Microambiente Tumoral , Células Dendríticas/imunologia , Humanos , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Microambiente Tumoral/imunologia , Imunoterapia , AnimaisRESUMO
Background: To design a vascular pedicled fascia-prosthesis compound model that can be used for ear reconstruction surgery. Methods: A vascularized tissue engineering chamber model was constructed in New Zealand rabbits, and fresh tissues were obtained after 4 weeks. The histomorphology and vascularization of the newly born tissue compound were analyzed and evaluated by tissue staining and Micro-CT scanning. Results: The neoplastic fibrous tissue formed in the vascularized tissue engineering chamber with the introduction of abdominal superficial vessels, similar to normal fascia, was superior to the control group in terms of vascularization, vascular density, total vascular volume, and total vascular volume/total tissue volume. Conclusion: In vivo, introducing abdominal superficial vessels in the tissue engineering chamber prepped for ear prosthesis may form a well-vascularized pedicled fascia-prosthesis compound that can be used for ear reconstruction.
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Sodium-ion batteries (SIBs) have garnered extensive attentions in recent years as a low-cost alternative to lithium-ion batteries. However, achieving both high capacity and long cyclability in cathode materials remains a challenge for SIB commercialization. P3-type Na0.67Ni0.33Mn0.67O2 cathodes exhibit high capacity and prominent Na+ diffusion kinetics but suffer from serious capacity decay and structural deterioration due to stress accumulation and phase transformations upon cycling. In this work, a dual modification strategy with both morphology control and element doping is applied to modify the structure and optimize the properties of the P3-type Na0.67Ni0.33Mn0.67O2 cathode. The modified Na0.67Ni0.26Cu0.07Mn0.67O2 layered cathode with hollow porous microrod structure exhibits an excellent reversible capacity of 167.5 mAh g-1 at 150 mA g-1 and maintains a capacity above 95 mAh g-1 after 300 cycles at 750 mA g-1. For one thing, the specific morphology shortens the Na+ diffusion pathway and releases stress during cycling, leading to excellent rate performance and high cyclability. For another, Cu doping at the Ni site reduces the Na+ diffusion energy barrier and mitigates unfavorable phase transitions. This work demonstrates that the electrochemical performance of P3-type cathodes can be significantly improved by applying a dual modification strategy, resulting in reduced stress accumulation and optimized Na+ migration behavior for high-performance SIBs.
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Antimony selenide (Sb2Se3) is emerging as a promising photovoltaic material owing to its excellent photoelectric property. However, the low carrier transport efficiency, and detrimental surface oxidation of the Sb2Se3 thin film greatly influenced the further improvement of the device efficiency. In this study, the introduction of tellurium (Te) can induce the benign growth orientation and the desirable Sb/Se atomic ratio in the Te-Sb2Se3 thin film. Under various characterizations, it found that the Te-doping tended to form Sb2Te3-doped Sb2Se3, instead of alloy-type Sb2(Se,Te)3. After Te doping, the mitigation of surface oxidation has been confirmed by the Raman spectra. High-quality Te-Sb2Se3 thin films with preferred [hk1] orientation, large grain size, and low defect density can be successfully prepared. Consequently, a 7.61% efficiency Sb2Se3 solar cell has been achieved with a VOC of 474 mV, a JSC of 25.88 mA/cm2, and an FF of 64.09%. This work can provide an effective strategy for optimizing the physical properties of the Sb2Se3 absorber, and therefore the further efficiency improvement of the Sb2Se3 solar cells.
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As a potential substitute for lithium-ion battery, sodium-ion batteries (SIBs) have attracted a tremendous amount of attention due to their advantages in terms of cost, safety and sustainability. Nevertheless, further improvement of the energy density of cathode materials in SIBs remains challenging and requires the activation of anion redox reaction (ARR) activity to provide additional capacity. Herein, we report a high-performance Mn-based sodium oxide cathode material, Na0.67Mg0.1Zn0.1Mn0.8O2 (NMZMO), with synergistic activation of ARR by cosubstitution. This material can deliver an ultra-high capacity of â¼233 mAh/g at 0.1 C, which is significantly higher than their single-cation-substituted counterparts and among the best in as-reported MgMn or ZnMn-based cathodes. Various spectroscopic techniques were comprehensively employed and it was demonstrated that the higher capacity of NMZMO originated from the enhanced ARR activity. Neutron pair distribution function and resonant inelastic X-ray scattering experiments revealed that out-of-plane migration of Mg/Zn occurred upon charging and oxygen anions in the form of molecular O2 were trapped in vacancy clusters in the fully-charged-state. In NMZMO, Mg and Zn mutually interacted with each other to migrate toward tetrahedral sites, which provided a prerequisite for further ARR activity enhancement to form more trapped molecular O2. These findings provide unique insight into the ARR mechanism and can guide the development of high-performance cathode materials through ARR enhancement strategies.
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Fontes de Energia Elétrica , Óxidos , Oxirredução , Íons , Eletrodos , OxigênioRESUMO
a novel method for designing high channel-count fiber Bragg gratings (FBGs) is proposed. For the first time, tailored group delay is introduced into the target reflection spectra to obtain a more even distribution of the refractive index modulation. This approach results in the reduction of the maximum refractive index modulation to physically realizable levels. The maximum index modulation reduction factors are all greater than 5.5. This is a significant improvement compared with previously reported results. Numerical results show that the thus designed high channel-count FBG filters exhibit superior characteristics including 30 dB channel isolation, a flat-top and near 100% reflectivity in each channel.