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1.
ACS Appl Mater Interfaces ; 16(34): 44957-44966, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39137352

RESUMO

Ideal solid electrolytes for lithium (Li) metal batteries should conduct Li+ rapidly with low activation energy, exhibit a high Li+ transference number, form a stable interface with the Li anode, and be electrochemically stable. However, the lack of solid electrolytes that meet all of these criteria has remained a considerable bottleneck in the advancement of lithium metal batteries. In this study, we present a design strategy combining all of those requirements in a balanced manner to realize quasi-solid-state electrolyte-enabled Li metal batteries (LMBs). We prepared Li+-coordinated triptycene-based ionic porous organic polymers (Li+@iPOPs). The Li+@iPOPs with imidazolates and phenoxides exhibited a high conductivity of 4.38 mS cm-1 at room temperature, a low activation energy of 0.627 eV, a high Li+ transference number of 0.95, a stable electrochemical window of up to 4.4 V, excellent compatibility with Li metal electrodes, and high stability during Li deposition/stripping cycles. The high performance is attributed to charge delocalization in the backbone, mimicking the concept of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), which facilitates the diffusion of coordinated Li+ through the porous space of the triptycene-based iPOPs. In addition, Li metal batteries assembled using Li+@Trp-Im-O-POPs as quasi-solid-state electrolytes and a LiFePO4 cathode showed an initial capacity of 114 mAh g-1 and 86.7% retention up to 200 cycles.

2.
Free Radic Biol Med ; 223: 325-340, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111584

RESUMO

CX-5461, a first-in-class compound, is widely recognized as a selective inhibitor of RNA polymerase I. Recently, it has been reported to possess novel immunosuppressive properties with significant therapeutic effects in transplantation immune rejection. However, the potential use of CX-5461 for Systemic Lupus Erythematosus (SLE) treatment remains unknown. In this study, we elucidated the mechanism underlying the therapeutic efficacy of CX-5461 in lupus. Our findings demonstrated that CX-5461 selectively targets B cells and effectively reduces the proportions of B cells, germinal center B cells, and plasma cells in MRL/MPJ-Faslpr and Resiquimod (R848)-induced lupus mice. Molecular studies revealed that CX-5461 modulates CD36-Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4)-mediated glycerolipid metabolism in B cells, triggering ferroptosis through the p53- Solute Carrier Family 7 Member 11 (SLC7A11)- Arachidonate 12-Lipoxygenase (ALOX12) pathway, thereby decreasing IgG and Anti-Double-Stranded Deoxyribonucleic Acid (dsDNA) antibody levels and attenuating lupus. Collectively, these results suggest that CX-5461 holds promise as an effective candidate for targeted therapy against lupus.


Assuntos
Linfócitos B , Ferroptose , Lúpus Eritematoso Sistêmico , Proteína Supressora de Tumor p53 , Animais , Camundongos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/metabolismo , Lúpus Eritematoso Sistêmico/patologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/genética , Ferroptose/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linfócitos B/imunologia , Linfócitos B/patologia , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 12-Lipoxigenase/genética , Feminino , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Camundongos Endogâmicos MRL lpr , Modelos Animais de Doenças , Transdução de Sinais/efeitos dos fármacos , Humanos
3.
High Alt Med Biol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995860

RESUMO

Yu Liu, Zhengyang Zhang, Yongting Luo, Peng An, Jingyi Qi, Xu Zhang, Shuaishuai Zhou, Yongzhi Li, Chong Xu, Junjie Luo, and Jiaping Wang. Product of traditional Chinese medicine longgui yangxinwan protects the human body from altitude sickness damage by reducing oxidative stress and preventing mitochondrial dysfunction. High Alt Med Biol. 00:00-00, 2024. Background: Plateau reaction, caused by high-altitude exposure, results in symptoms like headaches, dyspnea, palpitations, fatigue, shortness of breath, and insomnia due to reduced oxygen levels. Mitochondria are crucial for high-altitude acclimatization as they regulate oxygen metabolism and cellular energy, reducing oxidative stress and maintaining bodily functions. Methods: The study participants were randomly divided into placebo group, Rhodiola group and longgui yangxinwan (Original name: taikong yangxinwan) group, with 20 people in each group. Three groups of subjects were sampled at three time points (PI: pre-intervention; P-D1: high-altitude day 1; P-D7: high-altitude day 7), and blood pressure, blood oxygen, heart rate, hemoglobin, and red blood cell count were measured. The ATP content, mitochondrial DNA copy number, expression of mitochondria-related genes, reactive oxygen species (ROS), glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) levels, and mitochondrial morphology were measured in blood at each time point. Results: Our study results demonstrate that longgui yangxinwan keeps the selected human physiological indicators stable and prevents mitochondrial dysfunction in the high altitude. Mechanically, longgui yangxinwan decreases the level of ROS in human serum, whereas increases the activity of the antioxidant enzyme GSH-PX. At high-altitude day 1 (P-D1) and high-altitude day 7 (P-D7), ROS in the placebo group were 1.5 and 2.2-fold higher than those of the longgui yangxinwan group, respectively. In addition, longgui yangxinwan enhances ATP production capacity, restores the levels of mitochondrial respiratory chain complexes, and effectively maintains mitochondrial morphology and integrity. At P-D1 and P-D7, the ATP levels in the longgui yangxinwan group were 19-fold and 26-fold higher than those in the placebo group, respectively. Conclusions: Our study highlights longgui yangxinwan as a potential drug for protecting humans from high-altitude damage by reducing oxidative stress and preventing mitochondrial dysfunction.

4.
Small ; : e2401120, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39031107

RESUMO

Defective layered bismuth oxychloride (BiOCl) exhibits excellent photocatalytic activities in water purification and environmental remediation. Herein, in situ single-molecule fluorescence microscopy is used to spatially resolve the photocatalytic heterogeneity and quantify the photoredox activities on individual structural features of BiOCl. The BiOCl nanoplates with respective dominant {001} and {010} facets (BOC-001 and BOC-010) are fabricated through tuning the pH of the solution. The corner position of BOC-001 exhibits the highest photo-oxidation turnover rate of 262.7 ± 30.8 s-1 µm-2, which is 2.1 and 65.7 times of those of edges and basal planes, respectively. A similar trend is also observed on BOC-010, which can be explained by the heterogeneous distribution of defects at each structure. Besides, BOC-001 shows a higher photoredox activity than BOC-010 at corners and edges. This can be attributed to the superior charge separation ability, active high-index facets of BOC-001, and its co-exposure of anisotropic facets steering the charge flow. Therefore, this work provides an effective strategy to understand the facet-dependent properties of single-crystalline materials at nanometer resolution. The quantification of site-specific photoredox activities on BiOCl nanoplates sheds more light on the design and optimization of 2D materials at the single-molecule level.

5.
Eur J Oncol Nurs ; 71: 102626, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878693

RESUMO

PURPOSE: The aim of this study was to improve the level of psychosocial adjustment and quality of life of patients with enterostomy by analyzing the subgroups of psychosocial adjustment and its influencing factors. METHODS: This was a multi-center cross-sectional study. On the basis of investigating the level of psychosocial adjustment of enterostomy patients, a profile model of psychosocial adjustment of patients with enterostomy was established by using latent profile analysis. Univariate analysis and multinomial logistical regression were used to analyze the factors affecting the different psychosocial adjustment subgroups of enterostomy patients. RESULTS: Psychosocial adjustment of 3840 patients with enterostomy can be divided into three latent characteristics: Moderately high psychosocial adjustment level and high positive emotion in enterostomy patients (24.5%), Medium psychosocial but low social life adjustment (64.6%), low psychosocial adjustment level and high negative emotion (10.9%). Multinomial logistic regression showed that enterostomy self-care knowledge score, gender, medical payment method, educational background, carer, and self-care ability were affecting the subgroup classification of psychosocial adjustment of enterostomy patients. CONCLUSION: The psychosocial adjustment level of enterostomy patients can be divided into three latent profiles, which have obvious classification characteristics. Future studies can provide individualized interventions for different subgroups of enterostomy patients to improve the psychosocial adjustment of enterostomy patients.


Assuntos
Adaptação Psicológica , Enterostomia , Qualidade de Vida , Neoplasias Retais , Humanos , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Enterostomia/psicologia , Idoso , Neoplasias Retais/cirurgia , Neoplasias Retais/psicologia , Adulto , Ajustamento Social , Inquéritos e Questionários
6.
Artigo em Inglês | MEDLINE | ID: mdl-38870514

RESUMO

Background: The implementation of intelligent logistics transmission systems signifies a key aspect of modernizing hospital logistics systems in today's healthcare infrastructure. The pneumatic logistics transmission system (PTS) represents a sophisticated solution for the swift and secure conveyance of medical documents, specimens, and pharmaceuticals within hospital premises. Objective: This study investigates the influence of integrating the 'pneumatic logistics transmission system + intelligent robot' on blood routine and coagulation function test outcomes. Methods: A comparative study was conducted and a total of 50 participants were included in the study. Blood samples were collected from participants, including those undergoing blood routine tests, individuals with anemia, and patients undergoing outpatient urine routine assessments. The study systematically evaluated the effects of integrating the pneumatic logistics transmission system + intelligent robot on conventional blood tests and blood coagulation function analyses. The study compared the results obtained from the two transmission methods to evaluate their effectiveness in preserving the integrity of the specimens during transit. Results: The study revealed statistically significant differences in blood counts (P < .05), hemoglobin levels, and hematocrit levels among anemia patients (P < .05), with no observed presence of white blood cells (P > .05). Furthermore, when compared to the manual transport group, the pneumatic logistics transport system + intelligent robot group exhibited statistically significant activity of coagulation factors (P < .05), while no statistical disparities were noted among coagulation function indexes (P > .05). Conclusion: The integration of pneumatic logistics with intelligent robotics in hospital transmission systems proves beneficial for transporting various medical specimens efficiently. This combined approach streamlines logistics processes and enhances overall operational effectiveness within healthcare facilities.

7.
Eur J Surg Oncol ; 50(6): 108336, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626589

RESUMO

INTRODUCTION: There has been a lack of research comparing the efficacy of various treatments for low anterior resection syndrome (LARS). METHODS: We conducted a comprehensive search across six electronic databases and a paired meta-analysis was undertaken to assess the effectiveness of the interventions. Furthermore, a network meta-analysis was utilized to compare the efficacy of different treatments for LARS. RESULTS: This study encompassed nine randomized controlled trials, involving a total of 450 patients. Compared to routine care, 5-HT3 receptor antagonists (follow-up<3 months) and percutaneous tibial nerve stimulation (3 months ≤ follow-up <6 months) were effective in reducing the LARS score. Pelvic floor rehabilitation (follow-up≤3 months) was effective in decreasing daily number of bowel movements when compared to routine care. The network meta-analysis indicated that 5-HT3 receptor antagonists (follow-up<3 months) were the most effective in reducing both the LARS score and the daily number of bowel movements. Transanal irrigation (3 months ≤ follow-up ≤ 12 months) was most effective in reducing the LARS score. Additionally, 5-HT3 receptor antagonists demonstrated relative efficacy in improving patients' quality of life (follow-up ≤ 1 month). CONCLUSIONS: This review indicates that 5-HT3 receptor antagonists and anal irrigation show significant promise in the treatment of LARS. Nevertheless, the contributions of percutaneous tibial nerve stimulation and pelvic floor rehabilitation to LARS treatment should not be overlooked. Given the clinical heterogeneity observed among the studies, the results should be interpreted with caution.


Assuntos
Metanálise em Rede , Protectomia , Humanos , Diafragma da Pelve , Complicações Pós-Operatórias/reabilitação , Complicações Pós-Operatórias/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Retais/cirurgia , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Nervo Tibial , Estimulação Elétrica Nervosa Transcutânea/métodos
8.
Org Lett ; 26(17): 3586-3590, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38651729

RESUMO

The direct functionalization of methylene C(sp3)-H bonds is one of the greatest challenges in transition metal-catalyzed C-H activation. Although Pd(0)-catalyzed intramolecular cyclization reactions of methylene C(sp3)-H bonds have been reported, intermolecular functionalization remains to be discovered. Herein, we report the first example of a Pd(0)-catalyzed intermolecular methylene C(sp3)-H functionalization reaction. By use of a N-heterocyclic carbene ligand, the methylene C(sp3)-H bonds of 1-(benzyloxy)-2-iodobenzenes are activated and disilylated with hexamethyldisilane, affording disilylated products.

9.
Cell Mol Biol Lett ; 29(1): 55, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643118

RESUMO

BACKGROUND: Viral myocarditis (VMC) is a disease resulting from viral infection, which manifests as inflammation of myocardial cells. Until now, the treatment of VMC is still a great challenge for clinicians. Increasing studies indicate the participation of miR-29b-3p in various diseases. According to the transcriptome sequencing analysis, miR-29b-3p was markedly upregulated in the viral myocarditis model. The purpose of this study was to investigate the role of miR-29b-3p in the progression of VMC. METHODS: We used CVB3 to induce primary cardiomyocytes and mice to establish a model of viral myocarditis. The purity of primary cardiomyocytes was identified by immunofluorescence. The cardiac function of mice was detected by Vevo770 imaging system. The area of inflammatory infiltration in heart tissue was shown by hematoxylin and eosin (H&E) staining. The expression of miR-29b-3p and DNMT3A was detected by quantitative real time polymerase chain reaction (qRT-PCR). The expression of a series of pyroptosis-related proteins was detected by western blot. The role of miR-29b-3p/DNMT3A in CVB3-induced pyroptosis of cardiomyocytes was studied in this research. RESULTS: Our data showed that the expression of miR-29b-3p was upregulated in CVB3-induced cardiomyocytes and heart tissues in mice. To explore the function of miR-29b-3p in CVB3-induced VMC, we conducted in vivo experiments by knocking down the expression of miR-29b-3p using antagomir. We then assessed the effects on mice body weight, histopathology changes, myocardial function, and cell pyroptosis in heart tissues. Additionally, we performed gain/loss-of-function experiments in vitro to measure the levels of pyroptosis in primary cardiomyocytes. Through bioinformatic analysis, we identified DNA methyltransferases 3A (DNMT3A) as a potential target gene of miR-29b-3p. Furthermore, we found that the expression of DNMT3A can be modulated by miR-29b-3p during CVB3 infection. CONCLUSIONS: Our results demonstrate a correlation between the expression of DNMT3A and CVB3-induced pyroptosis in cardiomyocytes. These findings unveil a previously unidentified mechanism by which CVB3 induces cardiac injury through the regulation of miR-29b-3p/DNMT3A-mediated pyroptosis.


Assuntos
MicroRNAs , Miocardite , Animais , Camundongos , Antagomirs/metabolismo , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Miocardite/genética , Miocardite/metabolismo , Miócitos Cardíacos/metabolismo , Piroptose
10.
Int J Mol Sci ; 25(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38473909

RESUMO

Mutations of the FBN1 gene lead to Marfan syndrome (MFS), which is an autosomal dominant connective tissue disorder featured by thoracic aortic aneurysm risk. There is currently no effective treatment for MFS. Here, we studied the role of mitochondrial dysfunction in the phenotypic transformation of human smooth muscle cells (SMCs) and whether a mitochondrial boosting strategy can be a potential treatment. We knocked down FBN1 in SMCs to create an MFS cell model and used rotenone to induce mitochondrial dysfunction. Furthermore, we incubated the shFBN1 SMCs with Coenzyme Q10 (CoQ10) to assess whether restoring mitochondrial function can reverse the phenotypic transformation. The results showed that shFBN1 SMCs had decreased TFAM (mitochondrial transcription factor A), mtDNA levels and mitochondrial mass, lost their contractile capacity and had increased synthetic phenotype markers. Inhibiting the mitochondrial function of SMCs can decrease the expression of contractile markers and increase the expression of synthetic genes. Imposing mitochondrial stress causes a double-hit effect on the TFAM level, oxidative phosphorylation and phenotypic transformation of FBN1-knockdown SMCs while restoring mitochondrial metabolism with CoQ10 can rapidly reverse the synthetic phenotype. Our results suggest that mitochondria function is a potential therapeutic target for the phenotypic transformation of SMCs in MFS.


Assuntos
Síndrome de Marfan , Doenças Mitocondriais , Ubiquinona/análogos & derivados , Humanos , Síndrome de Marfan/genética , Fenótipo , Miócitos de Músculo Liso/metabolismo , Doenças Mitocondriais/metabolismo , Fibrilina-1/metabolismo , Adipocinas/metabolismo
11.
J Clin Nurs ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528346

RESUMO

AIMS: This study aimed to explore the psychosocial adjustment of enterostomy patients on a national scale. DESIGN: Based on a national cross-sectional survey. METHODS: From December 2021 and February 2023, a total of 22,040 enterostomy patients were assessed using the ostomy adjustment inventory-20. Initial analysis involved employing the chi-square test or Kruskal-Wallis H test to identify factors influencing the psychosocial adjustment of these patients. Subsequently, multinomial logistic regression was used to determine the factors affecting the classification of psychosocial adjustment levels of enterostomy patients. The reporting of this study adhered to the STROBE checklist. RESULTS: Eventually 21,124 patients with enterostomy were included in this study, out of which 7788 (36.9%) patients with low level of psychosocial adjustment, 11,803 (55.8%) patients with medium level of psychosocial adjustment and 1533 (7.3%) patients with high level of psychosocial adjustment. The factors influencing the classification of psychosocial adjustment levels of enterostomy patients were gender, educational background, carer, enterostomy self-care knowledge score and medical payment method. CONCLUSIONS: The overall psychosocial adjustment level of enterostomy patients is not optimistic, and the factors that may affect the classification of their psychosocial adjustment level are analysed. Individualised intervention should be given according to different psychosocial adjustment levels of enterostomy patients. RELEVANCE TO CLINICAL PRACTICE: The number of enterostomy patients with a high level of psychosocial adjustment is small in relation to the total number of enterostomy patients, and caregivers can provide health education to enterostomy patients by analysing the factors affecting the level of psychosocial adjustment of enterostomy patients. PATIENT OR PUBLIC CONTRIBUTION: None.

12.
Nutrients ; 16(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38337710

RESUMO

Procuring food enriched with diverse nutrients is pivotal for maintaining a robust immune system. However, the food system is now unprecedentedly globalized and faces challenges arising from climate change, pandemics, and political unrest. This study aims to illuminate the gap in exploring the adequacy and distribution equity of nutrition supplies in response to potential trade fluctuations and restrictions on agrifood within China's local agriculture endowments. Also, it seeks to identify the role of trade in contributing to these indices. Accordingly, we analyzed the distribution of nutrients in agrifood categories from production to consumption and assessed the adequacy and distribution equity of corresponding available nutrition supply from the local food provision system in terms of meeting residents' nutritional requirements, across China, and compared with those in the practical market. The local self-supply system showed that 12 out of 31 provinces have difficulty achieving an iron supply with 11% to 108% deficiencies. Except for iron, 52% (folate)-90% (vitamin B12) of agricultural output was available for diet provisioning nationwide. While food trade emerges as a crucial factor in enhancing secure and equitable nutrition supply, risks associated with micronutrient deficiencies necessitate careful consideration in current global circumstances. Our analysis explored a regional pool of nutrient information in supplements to the conventional food profile in China and could implicate better knowledge toward healthier food supplies and tailored improvements for achieving a resilient nutrition supply.


Assuntos
Dieta , Estado Nutricional , Suplementos Nutricionais , Ferro , China
13.
Sci Total Environ ; 922: 171216, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38412878

RESUMO

A large portion of Central-Western Asia is made up of contiguous closed basins, collectively termed as the Asian Endorheic Basins (AEBs). As these retention basins are only being replenished by the intermittent and scarce rainfall, global warming coupled with ever-rising human demand for water is exerting unprecedented pressures on local water and ecological security. Recent studies revealed a persistent and widespread water storage decline across the AEBs, yet the response of dryland vegetation to this recent hydroclimatic trend and a spatially explicit partitioning of the impact into the hydroclimatic factors and human activities remain largely unknown. To fill in this knowledge gap, we conducted trend and partial correlation analysis of vegetation and hydroclimatic change from 2001 to 2021 using multi-satellite observations, including vegetation greenness, total water storage anomalies (TWSA) and meteorological data. Here we show that much of the AEB (65.53 %), encompassing Mongolia Plateau, Northwest China, Qinghai Tibet Plateau, and Western Asia (except the Arabian Peninsula), exhibited a significant greening trend over the past two decades. In arid AEB, precipitation dominated the vegetation productivity trend. Such a rainfall dominance gave way to TWSA dominance in the hyper-arid AEB. We further showed that the decoupling of rainfall and hyper-arid vegetation greening was largely due to a significant expansion (17.3 %) in irrigated cropland across the hyper-arid AEB. Given the extremely harsh environment in the AEB, our results therefore raised a significant concern on the ecological and societal sustainability in this region, where a mild increase in precipitation cannot catch up the rising evaporative demand and water consumption resulted from global warming and agriculture intensification.

14.
Angew Chem Int Ed Engl ; 63(18): e202402202, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38375743

RESUMO

Poly(ethylene oxide) (PEO)-based electrolytes are often used for Li+ conduction as they can dissociate the Li salts efficiently. However, high entanglement of the chains and lack of pathways for rapid ion diffusion limit their applications in advanced batteries. Recent developments in ionic covalent organic frameworks (iCOFs) showed that their highly ordered structures provide efficient pathways for Li+ transport, solving the limitations of traditional PEO-based electrolytes. Here, we present imidazolate COFs, PI-TMEFB-COFs, having methoxyethoxy chains, synthesized by Debus-Radziszewski multicomponent reactions and their ionized form, Li+@PI-TMEFB-COFs, showing a high Li+ conductivity of 8.81 mS cm-1 and a transference number of 0.974. The mechanism for such excellent electrochemical properties is that methoxyethoxy chains dissociate LiClO4, making free Li+, then those Li+ are transported through the imidazolate COFs' pores. The synthesized Li+@PI-TMEFB-COFs formed a stable interface with Li metal. Thus, employing Li+@PI-TMEFB-COFs as the solid electrolyte to assemble LiFePO4 batteries showed an initial discharge capacity of 119.2 mAh g-1 at 0.5 C, and 82.0 % capacity and 99.9 % Coulombic efficiency were maintained after 400 cycles. These results show that iCOFs with ether chains synthesized via multicomponent reactions can create a new chapter for making solid electrolytes for advanced rechargeable batteries.

15.
Small ; 20(13): e2307057, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37972278

RESUMO

Understanding the underlying catalytic mechanisms with nanometer resolution is of critical importance to the rational design of 1D heterogeneous catalysts. However, a fundamental investigation of photocatalytic activities and kinetics at their individual sites is still challenging. Herein, in situ single-molecule fluorescence microscopy is employed to study the site-specific catalytic activities and dynamics on 1D-1D heterostructure for the first time. For carbon nanotube (CNT)/CdS nanorod composites, it is found that the CdS end with heterojunction exhibits the highest catalytic conversion rate constant of resazurin photoreduction, which is 30%, 7%, and 19% higher than those of the middle segment and the bare end of CdS, and the CNT end with heterojunction, respectively. A similar trend of adsorption abilities is observed in these structures. Such phenomena can be attributed to the different content of defects in these structures. Regarding the dissociation behaviors, the dissociation rate constants of all structures exhibit an opposite trend to those of adsorption and conversion. The direct and indirect dissociation are found to be predominant on CdS and CNT, respectively. Such investigation provides a deep insight into the understanding of site-specific properties on 1D heterogeneous catalysts and helps construct the "structure-dynamics" correlations at the nanoscale.

16.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38054519

RESUMO

The demand for applications, such as coatings, separation filters, and electronic packaging, has greatly driven the research of polymer films. At nanometer scale, mechanical properties of thin polymer films can significantly deviate from bulk. Despite outstanding progresses, there still lack deep discussions on nonlinear viscoelastic-viscoplastic response and their interactions under nanoconfinement. In this work, by conducting measurements via the bubble inflation method and modelling using Schapery and Perzyna equations, we demonstrate nonlinear viscoelastic-viscoplastic properties of freely standing thin polystyrene (PS) films. The results show the unchanged glassy compliance and the rubbery stiffening phenomenon for thin PS films, where the lower rubbery plateau in rubbery stiffening may originate from the induced molecular orientation by plastic deformation. With decreasing film thickness, viscosity and yield stress in viscoplasticity increase in an exponential and a linear trend, respectively, indicating the significant role of nanoconfinement effect on viscoplastic properties. These findings may reveal that there are many properties from linear viscoelasticity to nonlinear viscoelasticity-viscoplasticity that need to be explored and unveiled for sufficient understanding of the nanoconfinement effect on altering mechanical behavior of polymers.

17.
J Am Chem Soc ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37916601

RESUMO

Lithium (Li)-metal batteries (LMBs) possess the highest theoretical energy density among current battery designs and thus have enormous potential for use in energy storage. However, the development of LMBs has been severely hindered by safety concerns arising from dendrite growth and unstable interphases on the Li anode. Covalent organic frameworks (COFs) incorporating either redox-active or anionic moieties on their backbones have high Li-ion (Li+) conductivities and mechanical/chemical stabilities, so are promising for solid electrolyte interphases (SEIs) in LMBs. Here, we synthesized anthraquinone-based silicate COFs (AQ-Si-COFs) that contained both redox-active and anionic sites via condensation of tetrahydroxyanthraquinone with silicon dioxide. The nine Li+-mediated charge/discharge processes enabled the AQ-Si-COF to demonstrate an ionic conductivity of 9.8 mS cm-1 at room temperature and a single-ion-conductive transference number of 0.92. Computational studies also supported the nine Li+ mechanism. We used AQ-Si-COF as the solid electrolyte interphase on the Li anode. The LMB cells with a LiCoO2 cathode attained a maximum reversible capacity of 188 mAh g-1 at 0.25 C during high-voltage operation. Moreover, this LMB cell demonstrated suppressed dendrite growth and stable cyclability, with its capacity decreasing by less than 3% up to 100 cycles. These findings demonstrate the effectiveness of our redox-active and anionic COFs and their practical utility as SEI in LMB.

18.
Sci Rep ; 13(1): 16591, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789089

RESUMO

Disruptions of key food and fertilizer exports from Russia and Ukraine have exposed many countries to challenges accessing some commodities since these countries' war began. We evaluated the short-term, external, and direct impacts of disruptions of six food commodities and three types of fertilizer supplies from Russia and Ukraine on food access for all trading partners of the two countries by applying a set of trade and socioeconomic indicators. We found that the external food supplies of 279 countries and territories were affected to varying degrees; 24 countries-especially Georgia, Armenia, Kazakhstan, Azerbaijan, and Mongolia-are extremely vulnerable because they depend almost entirely on a variety of food imports from Russia and Ukraine. Access to fertilizers was affected in 136 countries and territories, particularly Estonia (potassic fertilizer), Mongolia (nitrogenous fertilizers), Kazakhstan (mixed fertilizers), and Brazil, the United States, China, and India (all types of fertilizers). An integrated assessment of countries' import types, purchasing power parity per capita, and populations indicated that the Democratic Republic of the Congo, Ethiopia, Egypt, and Pakistan are most vulnerable to such supply disruptions. Development of research into diversification and decentralization strategies for food access is needed to guide stable food supply policies.


Assuntos
Fertilizantes , Abastecimento de Alimentos , Ucrânia , Federação Russa , República da Geórgia , Armênia
19.
Angew Chem Int Ed Engl ; 62(44): e202311082, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37698088

RESUMO

We report an azide-functionalized cobaloxime proton-reduction catalyst covalently tethered into the Wurster-type covalent organic frameworks (COFs). The cobaloxime-modified COF photocatalysts exhibit enhanced photocatalytic activity for hydrogen evolution reaction (HER) in alcohol-containing solution with no presence of a typical sacrificial agent. The best performing cobaloxime-modified COF hybrid catalyzes hydrogen production with an average HER rate up to 38 µmol h-1 in ethanol/phosphate buffer solution under 4 h illumination. Ultrafast transient optical spectroscopy characterizations and charge carrier analysis reveal that the alcohol contents functioning as hole scavengers could be oxidized by the photogenerated holes of COFs to form aldehydes and protons. The consumption of the photogenerated holes thus suppresses exciton recombination of COFs and improves the ratio of free electrons that were effectively utilized to drive catalytic reaction for HER. This work demonstrates a great potential of COF-catalyzed HER using alcohol solvents as hole scavengers and provides an example toward realizing the accessibility to the scope of reaction conditions and a greener route for energy conversion.

20.
Acta Radiol ; 64(9): 2578-2589, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37593946

RESUMO

BACKGROUND: Accurate differentiation of nodular fasciitis (NF) from soft tissue sarcoma (STS) before surgery is essential for the subsequent diagnosis and treatment of patients. PURPOSE: To develop and evaluate radiomics nomograms based on clinical factors and magnetic resonance imaging (MRI) for the preoperative differentiation of NF from STS. MATERIAL AND METHODS: This retrospective study analyzed the MRI data of 27 patients with pathologically diagnosed NF and 58 patients with STS who were randomly divided into training (n = 62) and validation (n = 23) groups. Univariate and multivariate analyses were performed to identify the clinical factors and semantic features of MRI. Radiomics analysis was applied to fat-suppressed T1-weighted (T1W-FS) images, fat-suppressed T2-weighted (T2W-FS) images, and contrast-enhanced T1-weighted (CE-T1W) images. The radiomics nomograms incorporating the radiomics signatures, clinical factors, and semantic features of MRI were developed. ROC curves and AUCs were carried out to compare the performance of the clinical factors, radiomics signatures, and clinical radiomics nomograms. RESULTS: Tumor location, size, heterogeneous signal intensity on T2W-FS imaging, heterogeneous signal intensity on CE-T1W imaging, margin definitions on CE-T1W imaging, and septa were independent predictors for differentiating NF from STS (P < 0.05). The performance of the radiomics signatures based on T2W-FS imaging (AUC = 0.961) and CE-T1W imaging (AUC = 0.938) was better than that based on T1W-FS imaging (AUC = 0.833). The radiomics nomograms had AUCs of 0.949, which demonstrated good clinical utility and calibration. CONCLUSION: The non-invasive clinical radiomics nomograms exhibited good performance in the differentiation of NF from STS, and they have clinical application in the preoperative diagnosis of diseases.


Assuntos
Fasciite , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Nomogramas , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Sarcoma/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem , Fasciite/diagnóstico por imagem
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