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Building a stable cathode-electrolyte interface (CEI) is crucial for achieving high-performance layered metal oxide cathode materials LiNixCoyMn1-x-yO2 (NCM). In this work, a novel 4-fluorobenzene isocyanate (4-FBC) electrolyte additive that contains isocyanate and benzene ring functional groups is proposed, which can form robust and homogeneous N-rich and benzene ring skeleton CEI film on the cathode surface, leading to significant improvement in the electrochemical performance of lithium-ion batteries. Taking LiNi0.5Co0.2Mn0.3O2 (NCM523) as an example, the NCM523/SiO@Graphite pouch full cells with electrolytes containing a mass fraction of 1% 4-FBC additives demonstrate improved capacity retention after 200 cycles, retaining capacity retention rates of 81.3%, which is much higher than that of 39.1% without additive. The improvement can be ascribed to the mitigation of electrolyte decomposition and inhibition of transition metal ions the dissolution from the cathode material due to the stable CEI film. Moreover, the electrochemical performance enhancement can also be achieved in high voltage and Ni-rich cathode materials, indicating the universality and effectiveness of this strategy for the practical applications of high energy density lithium-ion batteries.
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Spinal cord injury (SCI) represents a profound central nervous system affliction, resulting in irreversibly compromised daily activities and disabilities. SCI involves excessive inflammatory responses, which are characterized by the existence of high levels of proinflammatory M1 macrophages, and neuronal mitochondrial energy deficit, exacerbating secondary damage and impeding axon regeneration. This study delves into the mechanistic intricacies of SCI, offering insights from the perspectives of neuroimmune regulation and mitochondrial function, leading to a pro-fibrotic macrophage phenotype and energy-supplying deficit. To address these challenges, we developed a smart scaffold incorporating enzyme mimicry nanoparticle-ceriumoxide (COPs) into nanofibers (NS@COP), which aims to pioneer a targeted neuroimmune repair strategy, rescuing CGRP receptor on macrophage and concurrently remodeling mitochondrial function. Our findings indicate that the integrated COPs restore the responsiveness of pro-inflammatory macrophages to calcitonin gene-related peptide (CGRP) signal by up-regulating receptor activity modifying protein 1 (RAMP1), a vital component of the CGRP receptor. This promotes macrophage fate commitment to an anti-inflammatory pro-resolution M2 phenotype, then alleviating glial scar formation. In addition, NS@COP implantation also protected neuronal mitochondrial function. Collectively, our results suggest that the strategy of integrating nanozyme COP nanoparticles into a nanofiber scaffold provides a promising therapeutic candidate for spinal cord trauma via rational regulation of neuroimmune communication and mitochondrial function.
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Axônios , Macrófagos , Nanofibras , Regeneração Nervosa , Traumatismos da Medula Espinal , Animais , Axônios/metabolismo , Nanofibras/química , Regeneração Nervosa/efeitos dos fármacos , Camundongos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Ratos , Alicerces Teciduais/química , Nanopartículas/química , Ratos Sprague-Dawley , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Feminino , Camundongos Endogâmicos C57BLRESUMO
The treatment of temporomandibular joint (TMJ) ankylosis in children is a great challenge for surgeons. Costochondral graft (CCG) is a common method of reconstructing the TMJ in children. However, the growth pattern of CCG is unpredictable. In this study, we introduced a surgical-orthodontic approach and evaluated the growth results of the mandible and maxilla in children with TMJ ankylosis through 3-dimensional computed tomography measurements. A prospective cohort study was conducted on child patients diagnosed as having TMJ ankylosis between September 1, 2018 and June 1, 2020. Computer-aided virtual mandibular position guided the CCG, and removable functional appliance was used after surgery. The maximal incisal opening (MIO), the maxilla height, and the length of mandibular ramus were determined. Paired t test was performed to analyze the differences among various stages. Six patients (3 females, 3 males; aged 6-9 y) were included in this study. MIO was 12.4 mm before surgery and improved to 36.8 mm after 42.8 months' follow-up. Mandible length increased by 5.1 mm in the affected side and by 5.3 mm in the unaffected side, without significant difference. The affected maxilla height increased by 6.7 mm, which was more than 5.0 mm in the unaffected side. In conclusion, continued growth of mandible and maxilla can be achieved through CCG combined with functional appliance treatment for children TMJ ankylosis.
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BACKGROUND: The competing interests of the government, smart senior care technology service providers, and older adults have led to a serious fragmentation of governance in China. This study aims to identify the collaboration mechanisms and evolutionary stabilization strategies for these agents. METHODS: An evolutionary game model is developed to analyze the strategic decisions made by the government, smart senior care technology service providers, and older adults. A sensitivity analysis is conducted using data from Anhui Province, China, to verify the effects of relevant parameters on the strategy decisions of each agent. RESULTS: The results of the simulation and sensitivity analysis indicated that, first, despite changes in the initial willingness values of the tripartite agents, the system eventually converges on 1. Second, the collaboration mechanism of the tripartite agents in the smart senior care system is related to government incentives, penalties, and subsidies, smart senior care service costs, and the additional benefits provided to smart senior care technology service providers. CONCLUSION: The strategy decisions of the government, providers, and older adults interact with each other. To promote collaboration among the tripartite agents and improve governance effectiveness, the government should strengthen the regulations for providers, increase penalties for providers that engage in a breach of trust, provide moderate incentives and subsidies, and control smart senior care service costs.
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Confiança , Humanos , Idoso , China , Simulação por ComputadorRESUMO
Developing efficient and low-cost oxygen evolution reaction (OER) electrodes is a pressing but still challenging task for energy conversion technologies such as water electrolysis, regenerative fuel cells, and rechargeable metal-air batteries. Hence, this study reports that a nickel oxide-nickel hybrid nanoarray on nickel foam (NiO-Ni/NF) could act as a versatile anode for superior water and urea oxidation. Impressively, this anode could attain high current densities of 50 and 100 mA cm-2 at extremely low overpotentials of 292 and 323 mV for OER, respectively. Besides, this electrode also shows excellent activity for urea oxidation with the need for just 0.28 and 0.36 V (vs SCE) to attain 10 and 100 mA cm-2 in 1.0 M KOH with 0.33 M urea, respectively. The enhanced oxidation performance should be due to the synergistic effect of NiO and Ni, improved conductivity, and enlarged active surface area.
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Nitric oxide (NO) abatement from engine exhaust is of great significance to alleviate air pollution and haze. Compared with the traditional selective catalytic reduction (SCR) technology, electrocatalytic decomposition of NO simplifies the reductant supply system and therefore avoids secondary pollution. In this study, typical perovskite La0.6Sr0.4CoxFe1-xO3-δ (LSCF) infiltrated by different dosages of nano ceria Ce0.9Gd0.1O1.9 (GDC) was used as composite cathodes, in order to explore the critical factors to restrain NO conversion in excess of O2. The results show that electron as reactive species transfers among NO, ABO3-type cathode and oxygen vacancy. The maximum of NO removal efficiency can reach 96.27 % in absence of O2 and up to 80.55 % in presence of 1% O2 in case of LSCF infiltrated by moderate dosages LSCF-GDC(2), which is superior to those of LSCF, LSCF-GDC(4) and LSM-GDC(nano) composite cathode. Compared to oxygen storage capacity (OSC) caused by the infiltration of nano ceria, higher surface oxygen exchange coefficient (kδ) and chemical diffusion coefficient (Dchem) lead to the significant decrease in polarization resistance (Rp), and consequently to the enhancement of NO removal in presence of O2. No matter what kind of oxygen deriving from oxygen reduction reaction (ORR) and NO reduction reaction (NORR), GDC infiltration into LSCF improves oxygen transport property and however, the property of cathode in ORR is dominant over in NORR in presence of O2. Moderate GDC loading has the highest oxygen transport kinetics, and oxygen surface exchange is faster than chemical diffusion, due to lower activation energy. Over loading of GDC with greater ohmic resistance (Rs) inversely influences the NO removal.
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Sensory nerves are long being recognized as collecting units of various outer stimuli; recent advances indicate that the sensory nerve also plays pivotal roles in maintaining organ homeostasis. Here, this study shows that sensory nerve orchestrates intervertebral disc (IVD) homeostasis by regulating its extracellular matrix (ECM) metabolism. Specifically, genetical sensory denervation of IVD results in loss of IVD water preserve molecule chondroitin sulfate (CS), the reduction of CS bio-synthesis gene chondroitin sulfate synthase 1 (CHSY1) expression, and dysregulated ECM homeostasis of IVD. Particularly, knockdown of sensory neuros calcitonin gene-related peptide (CGRP) expression induces similar ECM metabolic disorder compared to sensory nerve denervation model, and this effect is abolished in CHSY1 knockout mice. Furthermore, in vitro evidence shows that CGRP regulates nucleus pulposus cell CHSY1 expression and CS synthesis via CGRP receptor component receptor activity-modifying protein 1 (RAMP1) and cyclic AMP response element-binding protein (CREB) signaling. Therapeutically, local injection of forskolin significantly attenuates IVD degeneration progression in mouse annulus fibrosus puncture model. Overall, these results indicate that sensory nerve maintains IVD ECM homeostasis via CGRP/CHSY1 axis and promotes IVD repair, and this expands the understanding concerning how IVD links to sensory nerve system, thus shedding light on future development of novel therapeutical strategy to IVD degeneration.
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Peptídeo Relacionado com Gene de Calcitonina , Degeneração do Disco Intervertebral , Disco Intervertebral , Animais , Camundongos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Colforsina/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Matriz Extracelular/metabolismo , Homeostase , Disco Intervertebral/inervação , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Proteína 1 Modificadora da Atividade de Receptores/metabolismo , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Glucuronosiltransferase/metabolismoRESUMO
Recurrent low back pain after spinal surgeries, such as lumbar laminectomy, is a major complication of excessive epidural fibrosis. Although multiple preclinical and clinical methods have been aimed at ameliorating epidural fibrosis, their safety and efficacy remain largely unclear. Single implanted electrospun fibrous membranes provide physical barriers that can decrease tissue fibrosis after surgery; however, they also trigger local inflammation due to the implantation of a foreign body, thus subsequently attenuating their anti-fibrosis properties. Here, we designed a strategy that permits easy incorporation of mefloquine into polylactic acid membranes, and stable long-term mefloquine release, to potentially improve anti-fibrosis effects and relieve or prevent low back pain. The electrospun fibrous membranes grafted with mefloquine showed a well-controlled early temporary peak release, and secondary drug release occurred smoothly over several weeks. Histopathological and histomorphometric results indicated that the drug-loaded membranes had excellent anti-fibrosis effects after laminectomy in rats. Inflammation and neovascularization at the surgical site indicated that the mefloquine-grafted electrospun fibrous membranes provided sustained anti-inflammatory outcomes while effectively alleviating associated neuropathic pain hypersensitivity. In summary, our study indicated that polylactic acid-mefloquine grafted electrospun fibrous membranes may be a potential local agent to mitigate epidural fibrosis and support sensory neurological function after laminectomy, thereby potentially improving patients' postoperative outcomes.
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Undergraduate research (UR) refers to a series of scientific research activities for undergraduates. For the past few years in China, medical colleges and universities have increasingly attached importance on UR, aiming to provide undergraduates with better scientific research conditions, improve their understanding about scientific research and their basic scientific skills. Chinese medical undergraduates participate in scientific research spontaneously. However, the specific effects of UR are still unclear. In China, few quantitative standards to evaluate the detailed roles and effects of medical undergraduates' UR are available yet. To explore how UR influences Chinese medical undergraduates' scientific research abilities and their individual development, we conduct a cross-sectional analytical study by anonymous self-administered questionnaires. The questionnaires access the scientific research capabilities and qualities of students. The results show that students who participate in UR are equipped with better self-evaluation of designing research projects, using statistical software, making figures and charts, evaluating experimental results and performing experiments than those who do not; and the students who persist in UR have the highest self-evaluation on the abilities mentioned above. Hence, through quantitative criteria, it can be concluded that UR can help Chinese medical undergraduates build interest in scientific research, develop scientific thinking and basic research capacities, and set a solid foundation for future research. © 2018 International Union of Biochemistry and Molecular Biology, 47(1):41-50, 2018.
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Pesquisa Biomédica/educação , Educação de Graduação em Medicina , Estudantes de Medicina , Universidades , Feminino , Humanos , Masculino , Inquéritos e Questionários , Adulto JovemRESUMO
Surface coating modification on a polyethylene separator serves as a promising way to meet the high requirements of thermal dimensional stability and excellent electrolyte wettability for lithium ion batteries (LIBs). In this paper, we report a new type of surface modified separator by coating polyvinylidene fluoride (PVDF) organic particles on traditional microporous polyethylene (PE) separators. The PE separator coated by PVDF particles (PE-PVDF separator) has higher porosity (61.4%), better electrolyte wettability (the contact angle to water was 3.28° ± 0.21°) and superior ionic conductivity (1.53 mS/cm) compared with the bare PE separator (51.2%, 111.3° ± 0.12°, 0.55 mS/cm). On one hand, the PVDF organic polymer has excellent organic electrolyte compatibility. On the other hand, the PVDF particles contain sub-micro spheres, of which the separator can possess a large specific surface area to absorb additional electrolyte. As a result, LIBs assembled using the PE-PVDF separator showed better electrochemical performances. For example, the button cell using a PE-PVDF as the separator had a higher capacity retention rate (70.01% capacity retention after 200 cycles at 0.5 C) than the bare PE separator (62.5% capacity retention after 200 cycles at 0.5 C). Moreover, the rate capability of LIBs was greatly improved as well-especially at larger current densities such as 2 C and 5 C.
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A facile methodology to fabricate a metallic and selenophilic Ag2Se coating on a Se/nitrogen-doped mesoporous carbon composite, has been successfully developed based on the in situ redox reaction between Se and AgNO3 under ambient conditions. The in situ reactive growth of Ag2Se on Se ensures the complete encapsulation of Se by the Ag2Se coating, which endows the Ag2Se coating with the dual effects of physical entrapment and chemical binding to effectively confine polyselenide intermediates within the cathodes. With the further assistance of mesopore confinement of the nitrogen-doped carbons, the Ag2Se-coated Se/nitrogen-doped mesoporous carbon composites present much improved electrochemical performances with a high initial discharge capacity of 652 mA h g-1, a high coulombic efficiency of 95.4% and a high reversible capacity of 382 mA h g-1 after 100 cycles. These encouraging results suggest that the in situ reactive construction of metallic and chalcogenophilic coating layers on the chalcogen (e.g. S, Se and Te)-based electrode materials should be a promising and easy to scale-up method for practical applications of lithium batteries in light of the very simple in situ reaction processes involved.
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Oxygen evolution reaction (OER) plays a key role in various energy conversion and storage technologies, such as water electrolysis, regenerative fuel cells, and rechargeable metal-air batteries. However, the slow kinetics of OER limit the performance and commercialization of such devices. Herein, we report on NiFe LDH@Au hybrid nanoarrays on Ni foam for much enhanced OER. By hybridization of electronegative Au and NiFe LDH with intrinsic remarkable OER catalytic activity, this modular electrode could drive an overall ultrahigh-performance and robust OER in base with the demand of overpotentials of only 221, 235, and 270 mV to afford 50, 100, and 500 mA cm-2, respectively. Also, it exhibits superior catalytic activity and durability toward OER in 30 wt % KOH.