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A conjugated polymer, P4TTD-DPP, based on tetra-fused isoindigo-alt-diketopyrrolopyrrole, has been synthesized as a photothermal therapeutic nanotransducer within the near-infrared-II (NIR-II) window. P4TTD-DPP exhibits a notable mass extinction coefficient of 62.8 L g-1 cm-1 at 1064 nm. Additionally, P4TTD-DPP nanoparticles demonstrate remarkable photothermal conversion efficiency of 91.5% at 1064 nm and exhibit excellent anticancer efficacy under photothermal conditions.
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Antineoplásicos , Raios Infravermelhos , Polímeros , Polímeros/química , Polímeros/farmacologia , Polímeros/síntese química , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Sobrevivência Celular/efeitos dos fármacos , Nanopartículas/química , Indóis/química , Indóis/farmacologia , Terapia Fototérmica , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Pirróis/química , Pirróis/farmacologia , Fototerapia , Camundongos , Estrutura Molecular , AnimaisRESUMO
Thrombosis, characterized by blood clot formation within vessels, poses a significant medical challenge. Despite extensive research, the development of effective thrombosis therapies is hindered by substantial costs, lengthy development times, and high failure rates in medication commercialization. Conventional pre-clinical models often oversimplify cardiovascular disease, leading to a disparity between experimental results and human physiological responses. In response, we have engineered a photothrombosis-on-a-chip system. This microfluidic model integrates human endothelium, human whole blood, and blood flow dynamics and employs the photothrombotic method. It enables precise, site-specific thrombus induction through controlled laser irradiation, effectively mimicking both normal and thrombotic physiological conditions on a single chip. Additionally, the system allows for the fine-tuning of thrombus occlusion levels via laser parameter adjustments, offering a flexible thrombus model with varying degrees of obstruction. Additionally, the formation and progression of thrombosis noted on the chip closely resemble the thrombotic conditions observed in mice in previous studies. In the experiments, we perfused recalcified whole blood with Rose Bengal into an endothelialized microchannel and initiated photothrombosis using green laser irradiation. Various imaging methods verified the model's ability to precisely control thrombus formation and occlusion levels. The effectiveness of clinical drugs, including heparin and rt-PA, was assessed, confirming the chip's potential in drug screening applications. In summary, the photothrombosis-on-a-chip system significantly advances human thrombosis modeling. Its precise control over thrombus formation, flexibility in the thrombus severity levels, and capability to simulate dual physiological states on a single platform make it an invaluable tool for targeted drug testing, furthering the development of organ-on-a-chip drug screening techniques.
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Dispositivos Lab-On-A-Chip , Trombose , Humanos , Lasers , Técnicas Analíticas Microfluídicas/instrumentação , Animais , Rosa BengalaRESUMO
Introduction: Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of insulin-producing ß cells. Toll-like receptor 9 (TLR9) plays a role in autoimmune diseases, and B cell-specific TLR9 deficiency delays T1D development. Gut microbiota are implicated in T1D, although the relationship is complex. However, the impact of B cell-specific deficiency of TLR9 on intestinal microbiota and the impact of altered intestinal microbiota on the development of T1D are unclear. Objectives: This study investigated how gut microbiota and the intestinal barrier contribute to T1D development in B cell-specific TLR9-deficient NOD mice. Additionally, this study explored the role of microbiota in immune regulation and T1D onset. Methods: The study assessed gut permeability, gene expression related to gut barrier integrity, and gut microbiota composition. Antibiotics depleted gut microbiota, and fecal samples were transferred to germ-free mice. The study also examined IL-10 production, Breg cell differentiation, and their impact on T1D development. Results: B cell-specific TLR9-deficient NOD mice exhibited increased gut permeability and downregulated gut barrier-related gene expression. Antibiotics restored gut permeability, suggesting microbiota influence. Altered microbiota were enriched in Lachnospiraceae, known for mucin degradation. Transferring this microbiota to germ-free mice increased gut permeability and promoted IL-10-expressing Breg cells. Rag-/- mice transplanted with fecal samples from Tlr9 fl/fl Cd19-Cre+ mice showed delayed diabetes onset, indicating microbiota's impact. Conclusion: B cell-specific TLR9 deficiency alters gut microbiota, increasing gut permeability and promoting IL-10-expressing Breg cells, which delay T1D. This study uncovers a link between TLR9, gut microbiota, and immune regulation in T1D, with implications for microbiota-targeted T1D therapies.
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Diabetes Mellitus Tipo 1 , Microbioma Gastrointestinal , Interleucina-10 , Camundongos Endogâmicos NOD , Receptor Toll-Like 9 , Animais , Receptor Toll-Like 9/deficiência , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Microbioma Gastrointestinal/imunologia , Interleucina-10/metabolismo , Camundongos , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/microbiologia , Camundongos Knockout , Linfócitos B Reguladores/imunologia , Feminino , Linfócitos B/imunologia , Linfócitos B/metabolismoRESUMO
Global warming would significantly impact tree growth in the Tibetan Plateau. However, the specific effects of climate change on the radial growth of Pinus wallichiana in Mount Qomolangma are still uncertain. To investigate the responses of radial growth of P. wallichiana to climate change, we analyzed tree-ring samples in Mount Qomolangma. We removed the age-related growth trends and established three chronologies by using the modified negative exponential curve, basal area index, and regional curve standardization, and conducted Pearson correlation and moving correlation analyses to examine the association between radial growth of P. wallichiana and climatic factors. The results showed that this region had experienced a significant upward trend in temperature and that the Palmer drought severity index (PDSI) indicated a decreasing trend since 1980s, while the relative humi-dity changed from a significant upward to a downward trend around 2004, implying the climate shifted toward warmer and drier. Results of Pearson correlation analysis indicated a significant and positive relationship between the radial growth of P. wallichiana and the minimum temperature of April-June and July-September, and precipitation of January-April in the current year. The radial growth of P. wallichiana was significantly and negatively associated with the relative humidity of June, July, and August in the current year. As temperature rose after 1983, the relationship between radial growth of P. wallichiana and the minimum temperature in July and September of the current year increased from a non-significant association to a significant and positive association, while the relationship between radial growth of P. wallichiana and relative humidity in August and precipitation in September of the current year changed from non-significant correlation to a significant and negative correlation. Results of the moving correlation analysis suggested that the radial growth of P. wallichiana showed a significant and stable correlation with the July-September minimum temperature of the current year. Under the background of climate warming, the rapid increases of temperature would accelerate the radial growth of P. wallichiana in Mount Qomolangma.
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Mudança Climática , Tibet , Pinus/crescimento & desenvolvimento , Ecossistema , Temperatura , Caules de Planta/crescimento & desenvolvimento , Aquecimento GlobalRESUMO
Toll-like receptor 9 (TLR9) recognizes bacterial, viral and self DNA and play an important role in immunity and inflammation. However, the role of TLR9 in obesity is less well-studied. Here, we generate B-cell-specific Tlr9-deficient (Tlr9fl/fl/Cd19Cre+/-, KO) B6 mice and model obesity using a high-fat diet. Compared with control mice, B-cell-specific-Tlr9-deficient mice exhibited increased fat tissue inflammation, weight gain, and impaired glucose and insulin tolerance. Furthermore, the frequencies of IL-10-producing-B cells and marginal zone B cells were reduced, and those of follicular and germinal center B cells were increased. This was associated with increased frequencies of IFNγ-producing-T cells and increased follicular helper cells. In addition, gut microbiota from the KO mice induced a pro-inflammatory state leading to immunological and metabolic dysregulation when transferred to germ-free mice. Using 16 S rRNA gene sequencing, we identify altered gut microbial communities including reduced Lachnospiraceae, which may play a role in altered metabolism in KO mice. We identify an important network involving Tlr9, Irf4 and Il-10 interconnecting metabolic homeostasis, with the function of B and T cells, and gut microbiota in obesity.
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Linfócitos B , Dieta Hiperlipídica , Disbiose , Microbioma Gastrointestinal , Inflamação , Interleucina-10 , Camundongos Knockout , Obesidade , Receptor Toll-Like 9 , Animais , Obesidade/imunologia , Obesidade/microbiologia , Obesidade/metabolismo , Disbiose/imunologia , Disbiose/microbiologia , Receptor Toll-Like 9/metabolismo , Receptor Toll-Like 9/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Inflamação/metabolismo , Camundongos , Dieta Hiperlipídica/efeitos adversos , Interleucina-10/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Fatores Reguladores de InterferonRESUMO
There has been a major increase in Type 2 diabetes and obesity in many countries, and this will lead to a global public health crisis, which not only impacts on the quality of life of individuals well but also places a substantial burden on healthcare systems and economies. Obesity is linked to not only to type 2 diabetes but also cardiovascular diseases, musculoskeletal disorders, and certain cancers, also resulting in increased medical costs and diminished quality of life. A number of studies have linked changes in gut in obesity development. Dysbiosis, a deleterious change in gut microbiota composition, leads to altered intestinal permeability, associated with obesity and Type 2 diabetes. Many factors affect the homeostasis of gut microbiota, including diet, genetics, circadian rhythms, medication, probiotics, and antibiotics. In addition, bariatric surgery induces changes in gut microbiota that contributes to the metabolic benefits observed post-surgery. Current obesity management strategies encompass dietary interventions, exercise, pharmacotherapy, and bariatric surgery, with emerging treatments including microbiota-altering approaches showing promising efficacy. While pharmacotherapy has demonstrated significant advancements in recent years, bariatric surgery remains one of the most effective treatments for sustainable weight loss. However, access to this is generally limited to those living with severe obesity. This underscores the need for non-surgical interventions, particularly for adolescents and mildly obese patients. In this comprehensive review, we assess longitudinal alterations in gut microbiota composition and functionality resulting from the two currently most effective anti-obesity treatments: pharmacotherapy and bariatric surgery. Additionally, we highlight the functions of gut microbiota, focusing on specific bacteria, their metabolites, and strategies for modulating gut microbiota to prevent and treat obesity. This review aims to provide insights into the evolving landscape of obesity management and the potential of microbiota-based approaches in addressing this pressing global health challenge.
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Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Adolescente , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/complicações , Qualidade de Vida , Obesidade/metabolismoRESUMO
Emerging adulthood is the youth trajectory characterized by self-focus, identity exploration, feeling between adolescence and adulthood, instability, and experimentation. This trajectory was first identified in industrialized individualistic countries with gender equality and technological progress. To measure transition to adulthood, the Inventory of the Dimensions of Emerging Adulthood (IDEA) was created. Although emerging adulthood is considered universal, adaptations of the questionnaire across the 12 countries show different patterns, and its cross-cultural invariance has been underinvestigated. This study tests IDEA in three collectivistic countries - Armenia, China, and Russia. The sample consisted of 868 students (total male - 152, total female - 716) aged 18 to 29 years old. We tested the questionnaire separately in the three countries to check that this model fits, but we failed to prove it. After that we used a factor-analytic approach to find a common version for the three countries. We got a five-factor correlated model in accordance with the theory, but it was reduced from 31 items to 21, and three items moved to other factors. Finally, we provided measurement invariance and reached configural level. To test the narrower facets of factors we used multi-group alignment and found that variances in six parameters differ, mainly in Instability. Despite the difference in the questionnaire items, we proposed a common model for three countries that we called questionnaire IDEA-collectivistic countries (IDEA-CC).
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A series of thienoisoindigo (TIG)-based conjugated polymers (CPs) with high molecular weights are synthesized by direct arylation polycondensation (DArP) by using TIG derivatives as CBr monomer and multi-halogenated thiophene derivatives, i.e., (E)-1,2-bis(3,4-difluorothien-2-yl)ethene (4FTVT), (E)-1,2-bis(3,4-dichlorothien-2-yl)ethene (4ClTVT), 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT), and 3,3',4,4'-tetrachloro-2,2'-bithiophene (4ClBT), as CH monomers. Density functional theory (DFT) calculations reveal the high selectivity between α-CH bonds in 4FTVT, 4ClTVT, 4FBT, and 4ClBT and ß-CH bonds in TIG CBr monomer. All four resulting CPs exhibit low optical bandgaps of ca. 1.20 eV and ambipolar transport characteristics with both electron and hole mobility above 0.1 cm2 V-1 s-1 as elaborated with organic thin-film transistors (OTFTs). The polymer TIG-4FTVT delivers the best device performance. With this polymer, n-channel OTFTs with electron mobility up to 1.67 cm2 V-1 s-1 and p-channel OTFTs with hole mobility up to 0.62 cm2 V-1 s-1 are fabricated by modifying source/drain electrodes with polyethylenimine ethoxylated (PEIE) and MoO3 , respectively, to selectively inject electrons and holes.
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Etilenos , Polímeros , Polímeros/química , Tiofenos/química , ElétronsRESUMO
BACKGROUND: The cryoablation efficacy of semisolid freezing nitrogen ethanol composite (FNEC) has been demonstrated. We aimed to investigate the feasibility of adjuvant FNEC-assisted cryoablation in different bone cavity types by assessing the perioperative complication rates. METHODS: The medical charts of patients who received intraoperative adjuvant cryoablation using semisolid FNEC for bone tumors from December 2013 to January 2018 were reviewed. The bone cavities were categorized into three types according to liquid spill potential (type 1, able to hold liquid without limb manipulation; type 2, required extensive limb manipulation to retain liquid; type 3, unable to retain liquid). The overall complication rate and the complication rates stratified by bone cavity type were determined. RESULTS: Among the 76 patients, 30.3%, 57.9%, and 11.8% had type 1, 2, and 3 bone cavities, respectively. The mean follow-up time for perioperative complications was 43.5 ± 24.1 days. Five patients experienced complications, including two cases of skin damage, two cases of skin infection, and one case of fracture, yielding an overall perioperative complication rate of 6.4%. All cases of skin damage and skin infection were superficial and manageable by oral antibiotics. The patient with a pathologic fracture recovered well after being treated with open reduction and plate fixation. No neuropraxia was noted within the first few days postsurgery in any patient. The complication rates in type 1, 2, and 3 bone cavities were 13%, 4.6%, and 0%, respectively. CONCLUSION: All bone cavity types had a low incidence of perioperative complications after treatment with adjuvant FNEC-assisted cryoablation. Semisolid FNEC-assisted cryoablation is a feasible alternative to overcome the liquid spill potential in bone cavities resulting from tumor resection and intralesional curettage.
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Neoplasias Ósseas , Criocirurgia , Humanos , Congelamento , Nitrogênio/uso terapêutico , Etanol/efeitos adversos , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Criocirurgia/efeitos adversos , Criocirurgia/métodos , Resultado do Tratamento , Estudos RetrospectivosRESUMO
Electroreduction of nitric oxide (NO) to NH3 (NORR) has gained extensive attention for the sake of low carbon emission and air pollutant treatment. Unfortunately, NORR is greatly hindered by its sluggish kinetics, especially under low concentrations of NO. Herein, we developed a chlorine (Cl) vacancy strategy to overcome this limitation over FeOCl nanosheets (FeOCl-VCl ). Density functional theory (DFT) calculations revealed that the Cl vacancy resulted in defective Fe with sharp d-states characteristics in FeOCl-VCl to enhance the absorption and activation of NO. In situ X-ray absorption near-edge structure (XANES) and attenuated total reflection-infrared spectroscopy (ATR-IR) verified the lower average oxidation state of defective Fe to enhance the electron transfer for NO adsorption/activation and facilitate the generation of key NHO and NHx intermediates. As a result, the FeOCl-VCl exhibited superior NORR activities with the NH3 Faradaic efficiency up to 91.1 % while maintaining a high NH3 yield rate of 455.4â µg cm-2 h-1 under 1.0â vol % NO concentration, competitive with those of previously reported literatures under higher NO concentration. Further, the assembled Zn-NO battery utilizing FeOCl-VCl as cathode delivered a record peak power density of 6.2â mW cm-2 , offering a new route for simultaneous NO removal, NH3 production, and energy supply.
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Dispersion relations govern wave behaviors, and tailoring them is a grand challenge in wave manipulation. We demonstrate the inverse design of phononic dispersion using nonlocal interactions on one-dimensional spring-mass chains. For both single-band and double-band cases, we can achieve any valid dispersion curves with analytical precision. We further employ our method to design phononic crystals with multiple ordinary (roton or maxon) and higher-order (undulation) critical points and investigate their wave packet dynamics.
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This study develops a framework for determining the material parameters of layered engineered wood in a nondestructive manner. The motivation lies in enhancing nondestructive evaluation (NDE) and quality assurance (QA) for engineered wood or mass timber, promising construction materials for sustainable and resilient civil structures. The study employs static compression tests, guided wave measurements, and a genetic algorithm (GA) to solve the inverse problem of determining the mechanical properties of a laminated veneer lumber (LVL) bar. Miniature LVL samples are subjected to compression tests to derive the elastic moduli and Poisson's ratios. Due to the intrinsic heterogeneity, the destructive compression tests yield large coefficients of variances ranging from 2.5 to 73.2%. Dispersion relations are obtained from spatial-temporal sampling of dynamic responses of the LVL bar. The GA pinpoints optimal mechanical properties by updating orthotropic elastic constants of the LVL material, and thereby dispersion curves, in a COMSOL simulation in accordance with experimental dispersion relations. The proposed framework can support estimation accuracy with errors less than 10% for most elastic constants. Focusing on vertical flexural modes, the estimated elastic constants generally resemble reference values from compression tests. This is the first study that evaluates the feasibility of using guided waves and multi-variable optimization to gauge the mechanical traits of LVL and establishes the foundation for further advances in the study of layered engineered wood structures.
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We study the dissipative bistable Duffing oscillator with equal energy wells and observe fractal patterns in the parameter space of driving frequency, forcing amplitude, and damping ratio. Our numerical investigation reveals the Hausdorff fractal dimension of the boundaries that separate the oscillator's intrawell and interwell behaviors. Furthermore, we categorize the interwell behaviors as three steady-state types: switching, reverting, and vacillating. While fractal patterns in the phase space are well known and heavily studied, our results point to another research direction about fractal patterns in the parameter space. Another implication of this study is that the vibration of a continuous bistable system modeled using a single-mode approximation also manifests fractal patterns in the parameter space. In addition, our findings can guide the design of next-generation bistable and multistable mechanical metamaterials.
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The objective of this study is to develop a device to mimic a microfluidic system of human arterial blood vessels. The device combines fluid shear stress (FSS) and cyclic stretch (CS), which are resulting from blood flow and blood pressure, respectively. The device can reveal real-time observation of dynamic morphological change of cells in different flow fields (continuous flow, reciprocating flow and pulsatile flow) and stretch. We observe the effects of FSS and CS on endothelial cells (ECs), including ECs align their cytoskeleton proteins with the fluid flow direction and paxillin redistribution to the cell periphery or the end of stress fibers. Thus, understanding the morphological and functional changes of endothelial cells on physical stimuli can help us to prevent and improve the treatment of cardiovascular diseases.
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Background: The decreased osteogenic differentiation ability of mesenchymal stem cells (MSCs) is one of the important reasons for SOP. Inhibition of Wnt signaling in MSCs is closely related to SOP. Microtubule actin crosslinking factor 1 (MACF1) is an important regulator in Wnt/ß-catenin signal transduction. However, whether the specific expression of MACF1 in MSC regulates SOP and its mechanism remains unclear. Methods: We established MSC-specific Prrx1 (Prx1) promoter-driven MACF1 conditional knock-in (MACF-KI) mice, naturally aged male mice, and ovariectomized female mice models. Micro-CT, H&E staining, double calcein labeling, and the three-point bending test were used to explore the effects of MACF1 on bone formation and bone microstructure in the SOP mice model. Bioinformatics analysis, ChIP-PCR, qPCR, and ALP staining were used to explore the effects and mechanisms of MACF1 on MSCs' osteogenic differentiation. Results: Microarray analysis revealed that the expression of MACF1 and positive regulators of the Wnt pathway (such as TCF4, ß-catenin, Dvl) was decreased in human MSCs (hMSCs) isolated from aged osteoporotic than non-osteoporotic patients. The ALP activity and osteogenesis marker genes (Alp, Runx2, and Bglap) expression in mouse MSCs was downregulated during aging. Furthermore, Micro-CT analysis of the femur from 2-month-old MSC-specific Prrx1 (Prx1) promoter-driven MACF1 conditional knock-in (MACF-cKI) mice showed no significant trabecular bone changes compared to wild-type littermate controls, whereas 18- and 21-month-old MACF1 c-KI animals displayed increased bone mineral densities (BMD), improved bone microstructure, and increased maximum compression stress. In addition, the ovariectomy (OVX)-induced osteoporosis model of MACF1 c-KI mice had significantly higher trabecular volume and number, and increased bone formation rate than that in control mice. Mechanistically, ChIP-PCR showed that TCF4 could bind to the promoter region of the host gene miR-335-5p. Moreover, MACF1 could regulate the expression of miR-335-5p by TCF4 during the osteogenic differentiation of MSCs. Conclusion: These data indicate that MACF1 positively regulates MSCs osteogenesis and bone formation through the TCF4/miR-335-5p signaling pathway in SOP, suggesting that targeting MACF1 may be a novel therapeutic approach against SOP. The translational potential of this article: MACF1, an important switch in the Wnt signaling pathway, can alleviate SOP through the TCF4/miR-335-5p signaling pathway in mice model. It might act as a therapeutic target for the treatment of SOP to improve bone function.
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This corrects the article DOI: 10.1103/PhysRevE.101.022210.
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The unique structures of polynuclear MoxSy clusters make it possible to maximize the number of their active sites and for them to be good candidates for HER catalysts. An appropriate support is highly necessary not only to avoid the desorption of MoxSy clusters in a working environment, but also to improve their HER activity. Our work here shows that the CeO2 support could provide strong support for interaction with various MoxSy clusters and the formed MoxSy/CeO2 hetero-structures also have modest ΔGH* for the HER. The electronic features of MoxSy clusters are regulated by the CeO2 support, which leads to charge redistribution on edge atoms and plays a key role in H adsorption. Our studies provide instructive predictions on efficient candidates of molybdenum-sulfur based catalysts for the HER.
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Electrochemical N2reduction reaction (NRR) for NH3synthesis, which usually needs highly-efficient electrocatalysts for N2activation, is a carbon-neutral alternation compared to the traditional Haber-Bosch process. Although Ti-based compounds is widely used as electrocatalysts, what Ti defect affects NRR activity is still illusive. In this work, our systematic density functional calculations on Ti defect-decorated titanium oxide disclose that the unsaturated-Ti with the orbital splitting of defect electron states is the necessary feature for N2binding and activation, which can be further enhanced by increasing the splitting degree. The bonding/antibonding orbital population and projected density of states indicate that the nature of N2binding and activation on Ti-defect site is attributed to the elimination of the bonding orbital population in the conduction bands and the formation of*πback-bonding in the valence bands. For the whole NRR process, the synergy of Ti-defect and oxygen vacancy (VO) promotes N2reduction, and the required maximum energy input scales quite well with the adsorption strength of*NNH. Finally, the formed volcano shape successfully predicts new candidate catalysts for ammonia synthesis, such as TiO2combined VOwith Ti interstitial or H atom. This work provides disclosure of the key elements on the rational design of Ti-based nanomaterial electrocatalysts for artificial N2fixation.
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Efficient and robust electrocatalysts are required for the oxygen evolution reaction (OER). Photosystem II-inspired synthetic transition metal complexes have shown promising OER activity in water-poor or mild conditions, yet challenges remain in the improvement of current density and performance stability for practical applications in alkaline electrolytes in contrast to solid-state oxide catalysts. Here, we report that a nickel pseudo-complex (bpy)zNiOxHy (bpy = 2,2'-bipyridine) catalyst, which bridges solid oxide and molecular catalysts, exhibits the highest OER activity among nickel-based catalysts with a turnover frequency of 1.1 s-1 at an overpotential of 0.30 volts, even outperforming iron-incorporated nickel (oxy)hydroxide under an identical nickel mass load. Benefiting from the strong coordination between bpy and nickel, this (bpy)zNiOxHy catalyst exhibits long-term stability in highly alkaline media at 1.0 mA cm-2 for over 200 h and at 20 mA cm-2 for over 60 h. Our findings indicate that dynamically coordinating a small amount of bpy in the catalyst layer efficiently sustains highly active nickel sites for water oxidation, demonstrating a general strategy for improving the activity of transition metal sites with active ligands beyond the incorporation of metal cations to form double-layered hydroxides.
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PURPOSE: The recycled autograft in biological reconstruction for osteosarcoma has satisfactory outcome. There are few studies about its efficacy in pathological fracture. The aim of the study is to compare the clinical results of recycled autograft to those of allograft in patients with high-grade osteosarcoma with pathological fracture. PATIENTS AND METHODS: Between October 2010 and March 2018, 30 patients with osteosarcoma combining pathological fracture underwent biological reconstruction. Eleven patients received recycled autograft via extracorporeal irradiation or freezing nitrogen and nineteen patients restored bone defect via allograft to accomplish biological reconstruction. RESULTS: The mean follow-up was 58.1 months (range 12-120). The mean time to graft-host union of limbs reconstructed using recycled autografts and allografts was 17.45 ± 13.54 and 12.63 ± 12.62 months, respectively, with no significant difference observed between groups (p = 0.176). The five year probability of graft failure therefore did not significantly differ between groups (p = 0.245). The patient five year survival rate was similar (p = 0.229). Post-operative complication rates were similar for the recycled autograft group (54.5%) and the allograft group (57.9%). CONCLUSION: The recycled autograft showed comparable clinical results, graft-host union time, complication rate, and graft survival to allograft in biological reconstruction for osteosarcoma with pathological fracture.