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1.
Med Gas Res ; 13(2): 72-77, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36204786

RESUMO

Diabetic peripheral neuropathy (DPN) is a complex disorder caused by long-standing diabetes. Oxidative stress was considered the critical creed in this DPN pathophysiology. Hydrogen has antioxidative effects on diabetes mellitus and related complications. However, there is still no concern on the beneficial effects of hydrogen in DPN. This paper aimed to evaluate the effects of exogenous hydrogen to reduce the severity of DPN in streptozotocin-induced diabetic rats. Compared with hydrogen-rich saline treatment, hydrogen inhalation significantly reduced blood glucose levels in diabetic rats in the 4th and 8th weeks. With regard to nerve function, hydrogen administration significantly attenuated the decrease in the velocity of motor nerve conduction in diabetic animals. In addition, hydrogen significantly attenuated oxidative stress by reducing the level of malondialdehyde, reactive oxygen species, and 8-hydroxy-2-deoxyguanosine and meaningfully enhanced the antioxidant capability by partially restoring the activities of superoxide dismutase. Further studies showed that hydrogen significantly upregulated the expression of nuclear factor erythroid-2-related factor 2 and downstream proteins such as catalase and hemeoxygenase-1 in the nerves of diabetic animals. Our paper showed that hydrogen exerts significant protective effects in DPN by downregulating oxidative stress via the pathway of nuclear factor erythroid-2-related factor 2, which suggests its potential value in clinical applications.


Assuntos
Diabetes Mellitus Experimental , Neuropatias Diabéticas , Fármacos Neuroprotetores , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Glicemia , Catalase/metabolismo , Catalase/farmacologia , Catalase/uso terapêutico , Desoxiguanosina/metabolismo , Desoxiguanosina/farmacologia , Desoxiguanosina/uso terapêutico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/metabolismo , Hidrogênio , Malondialdeído , NAD/metabolismo , NAD/farmacologia , NAD/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo , Ratos , Espécies Reativas de Oxigênio , Estreptozocina , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia , Superóxido Dismutase/uso terapêutico
2.
Med Gas Res ; 13(1): 23-28, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35946219

RESUMO

Demyelination of the cerebral white matter is the most common pathological change after carbon monoxide (CO) poisoning. Notch signaling, the mechanism underlying the differentiation of astrocytes and oligodendrocytes, is critical to remyelination of the white matter after brain lesion. The purpose of this work was to determine the effects of hyperbaric oxygen (HBO) on Notch signaling pathway after CO poisoning for the explanation of the protective effects of HBO on CO-poisoning-related cerebral white matter demyelination. The male C57 BL/6 mice with severe CO poisoning were treated by HBO. And HBO therapy shortened the escape latency and improved the body mass after CO poisoning. HBO therapy also significantly suppressed protein and mRNA levels of Notch1 and Hes5 after CO poisoning. Our findings suggested that HBO could suppress the activation of Notch signaling pathway after CO poisoning, which is the mechanism underlying the neuroprotection of HBO on demyelination after severe CO poisoning.


Assuntos
Intoxicação por Monóxido de Carbono , Doenças Desmielinizantes , Oxigenoterapia Hiperbárica , Animais , Intoxicação por Monóxido de Carbono/terapia , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/terapia , Masculino , Camundongos , Oxigênio , Transdução de Sinais
3.
Mol Clin Oncol ; 17(6): 157, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36338605

RESUMO

To date, great progress has been made in studying the immunology of cancer and the development of immunotherapies. Immunotherapy has become an effective clinical strategy for cancer treatment in courtesy of its unique features. It has been demonstrated to delay tumor progression, reduce tumor recurrence and metastasis, and even cure tumors through enhancing the immune response, stimulating tumor-specific immunity and breaking immune tolerance. Several different immunotherapeutic approaches and methods are in the process of being developed, including the use of cytokines, immune checkpoint inhibitors, engineered T cells (such as T-cell-receptor T cells and chimeric antigen receptor T cells) and cancer vaccines. Digestive system neoplasms pose a serious threat to human health, including esophageal cancer, gastric cancer and colorectal cancer, and immunotherapy is considered to be a promising new avenue for the treatment of digestive system neoplasms. However, certain challenges remain in terms of the broad implementation of immunotherapies due to the incompletely understood mechanisms underlying tumorigenesis. Therefore, it is crucially important to understand both the various different types of immunotherapy and the immune landscapes in digestive system neoplasms in order to reduce the side effects associated with these therapies. The present review discusses existing and newly emerging immunotherapeutic methods that may be applied in the treatment of digestive system neoplasms and how their clinical efficacy may be enhanced.

4.
Emerg Microbes Infect ; : 1-9, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36394478

RESUMO

Enterovirus 76 (EV-A76) is a serotype of enterovirus A has been rarely reported. In this paper, we present the genetic characteristics of 15 EV-A76 isolates reported to circulate in the Xinjiang Uighur autonomous region of China in 2011. Sequence analysis revealed that all Chinese EV-A76 isolates had high similarity (> 98.3%) in the VP1 region, and five Chinese EV-A76 isolates were selected for whole genome sequencing based on VP1 nucleotide divergence. Similarity plots and boot-scanning analyses revealed frequent intertypic recombination in the nonstructural region of the EV-A76 isolate, as found with the EV-A89 donor sequence (also isolated in Xinjiang). The breakpoint of recombination is around nucleotide 3960, and the recombinant fragments covered part 2C and all P3 regions. This study increases publicly available EV-A76 nucleotide sequence and further our understanding EV-A76 molecular epidemiology.

5.
Front Chem ; 10: 1052574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36385989

RESUMO

Solution-processed scintillators hold great promise in fabrication of low-cost X-ray detectors. However, state of the art of these scintillators is still challenging in their environmental toxicity and instability. In this study, we develop a class of tetradecagonal CuI microcrystals as highly stable, eco-friendly, and low-cost scintillators that exhibit intense radioluminescence under X-ray irradiation. The red broadband emission is attributed to the recombination of self-trapped excitons in CuI microcrystals. We demonstrate the incorporation of such CuI microscintillator into a flexible polymer to fabricate an X-ray detector for high-resolution imaging with a spatial resolution up to 20 line pairs per millimeter (lp mm-1), which enables sharp image effects by attaching the flexible imaging detectors onto curved object surfaces.

6.
Front Cell Dev Biol ; 10: 962389, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36393842

RESUMO

The current immunotherapy strategy for breast cancer is limited. Tumor neoantigens have been proven to be a promising biomarker and potential target of immunotherapy in a variety of tumors. However, their effectiveness for breast cancer remains unclear. Immunogenic cell death (ICD) is a regulated form of cell death that can reshape the tumor immune microenvironment and activate adaptive immune responses. To this end, we screened potential antigens that could be used both for the development of immunotherapy and differentiating the patient-specific immune responses based on ICD-related risk signatures, in order to formulate an accurate scheme for breast cancer immunotherapy. We retrieved the gene expression profiles of the breast invasive cancer cohort and their corresponding clinical control data from The Cancer Genome Atlas. The Gene Expression Profiling Interactive Analysis (GEPIA) database was used to evaluate tumor antigen expression, the cBioPortal program was used to identify genetic variations, and the TIMER website was used to estimate the immune infiltration signatures. The risk score predictive model based on the ICD-related genes was constructed using the least absolute shrinkage and selection operator (LASSO) Cox regression algorithm, and the cohort was divided into low- and high-risk score groups. Two tumor antigens, namely, CCNE1 and PLK1, were associated with poor prognosis and infiltration of antigen-presenting cells. Furthermore, the ICD-related risk signature could significantly predict survival outcomes. The risk groups based on the ICD-related signature predictive model showed diverse immune infiltration and molecular and clinical features. The high-risk group was associated with low immune cell infiltration, immune score, expression of immune checkpoints, and human leukocyte antigen genes but high levels of CCNE1 and PLK1 and poor survival outcome. In conclusion, CCNE1 and PLK1 were identified as potential antigens in breast cancer. The ICD-related prognostic model distinguished immune response heterogeneity and predicted prognosis. Patients with high ICD-related risk scores were suitable to receive combination treatments based on CCNE1 or PLK1 and immune checkpoint inhibitors. In the future, these results will help us develop more accurate treatment schemes for patients with breast cancer.

7.
Molecules ; 27(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36364446

RESUMO

A simple sample preprocessing method was developed for the quantitative determination of amantadine (AMT) in human plasma by liquid chromatography-tandem mass spectrometry cubed (LC-MS3). The LC-MS3 system comprised a Shimadzu Exion LC-20AD HPLC pump coupled with a QTRAP 5500 mass spectrometer. First, the plasma samples were pretreated using acetonitrile as the extracting solution to precipitate protein. Next, amantadine and amantadine-d15 (AMT-d15) were separated on an Agilent Poroshell 120 SB-C18 column (4.6 mm × 50 mm, 2.7 µm) using isocratic elution with solvent A (70% 0.1% formic acid) and solvent B (30% acetonitrile) at a flow rate of 0.8 mL/min. The total run time for each sample was 3 min. The system used triple-stage fragmentation transitions at m/z 152.2→135.3→107.4 for AMT quantification in the positive ion mode and m/z 167.0→150.3→118.1 for AMT-d15 quantification. The LC-MS3 assay was linear (r > 0.995) with a concentration range of 50-1500 ng/mL. The lower limit of quantification (LLOQ) was 50 ng/mL, and the intra-day and inter-day accuracies and precisions were less than 8.0% at all concentrations. In addition, the recoveries and matrix effect for AMT in human plasma were within acceptable limits. In terms of stability, AMT had no significant degradation under all conditions. All the results met the requirements of the guidelines of the Food and Drug Administration (FDA) for biological method validation. The novelty of the MS3 assay was that it presented a methodology with higher selectivity and sensitivity. This method was successfully applied to 44 human plasma samples, and the obtained quantitative results were compared with another liquid chromatography-multiple reaction monitoring (LC-MRM) method. The Passing-Bablok regression coefficients and Bland-Altman plot revealed no difference between the LC-MS3 and LC-MRM methods, implying that the developed LC-MS3 method is a reliable and accurate assay for AMT determination in human plasma. These results are also a proof of concept for determining chemicals in biological samples by the LC-MS3 strategy.


Assuntos
Amantadina , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Acetonitrilas , Solventes , Reprodutibilidade dos Testes
8.
Am J Transl Res ; 14(10): 7226-7232, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36398228

RESUMO

OBJECTIVES: The aim of this study was to investigate the impact of unified discharge standards on the clinical efficacy and prognosis of hemiarthroplasty in elderly patients with hip fractures. METHODS: Retrospective study of 158 elderly patients with hip fractures who underwent artificial femoral head replacement in our hospital from March 2016 to July 2019 were enrolled. According to the unified discharge standards, patients were divided into the observation (65 cases who met discharge criteria) and control group (93 cases who failed to meet all discharge criteria). Histopathological feature, operation status, postoperative Harris Hip score, therapeutic outcome, postoperative complications, readmission and mortality rate were compared between the two groups. RESULTS: Surgery duration and intraoperative blood loss exhibited no difference between the two groups, while transfusion volume and length of hospital stay were significantly increased in the observation group. There was no significant difference in the Harris Hip score between the two groups 12 months postoperatively. The incidence of postoperative complications during the follow-up period was notably lower in the observation group. In addition, the three-month readmission rate and one-year mortality rate were significantly lower in the observation group. CONCLUSIONS: For elderly patients with hip fractures undergoing artificial femoral head replacement, the incidence of postoperative complications and postoperative readmission/mortality rate could be reduced through the establishment of unified discharge standards, which should be used in future clinical practice.

9.
Yi Chuan ; 44(9): 810-818, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36384957

RESUMO

Congenital hyperinsulinemia (CHI) is a disease phenotype characterized by persistent or recurrent hypoglycemia due to abnormal secretion of insulin by ß cells of the pancreas. CHI induced by activation mutation of a single allele of glucokinase (GCK) is the rarest type. In this paper, the clinical data of a patient with hypoglycemia of unknown cause were collected without obvious clinical symptoms. And a heterozygous missense mutation (c.295T> C:p.W99R) was detected in exon 3 of the GCK gene. The mutation was found in both the son and daughter of the proband, and the blood glucose level was low, while the others were normal. By summarizing and analyzing the characteristics of this case and the genetic pedigree of the family, the possibility of congenital hyperinsulinemia caused by a single gene mutation should be considered for hypoglycemia whose etiology is difficult to be determined clinically. This case also provides new clinical data for subsequent genetic studies of the disease.


Assuntos
Hiperinsulinismo , Hipoglicemia , Humanos , Glucoquinase/genética , Hipoglicemia/genética , Mutação , Testes Genéticos , Hiperinsulinismo/genética
10.
Rev Sci Instrum ; 93(10): 105002, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319357

RESUMO

Multi-degrees of freedom piezo-driven precision positioning platforms with large working strokes are demanded in many research fields. Although many multi-degrees of freedom piezo-driven positioning platforms have been proposed, few of them can achieve both large working stroke and high speed, which hinders their applications. In this study, a two-degrees of freedom piezo-driven positioning platform was proposed by stacking two identical stick-slip piezoelectric actuators. To simplify the practical implementation of a large working stroke, the actuator employed a special structure, in which the compliant mechanism and the slider were connected together as a mover and the guide rail was fixed as a stator. The working stroke of the actuator can be increased easily by increasing only the length of the guide rail without changing the output performances. By designing a lever-type compliant mechanism (LCM) on the side surface of the slider, a large loading space was obtained. Theoretical calculation and finite element analysis of the LCM were performed in detail. As the structures of these two stick-slip piezoelectric actuators are the same, only the output performances of the upper actuator (x direction) were tested as an example. Experimental results indicated that the upper actuator had a stable bi-direction motion with a working stroke being over 20 cm. The maximum speeds along the positive x and negative x directions reached 17.864 and 18.73 mm/s, and the resolutions were 100 and 230 nm, respectively. Furthermore, the vertical loading capacity was larger than 60 N.

11.
Pathogens ; 11(11)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36422630

RESUMO

Echovirus, a member of the Enterovirus B (EV-B) family, has led to numerous outbreaks and pandemics, causing a broad spectrum of diseases. Based on the national hand, foot, and mouth disease (HFMD) surveillance system, seven strains of echovirus 33 (E33) were isolated from Mainland of China between 2010 and 2018. The whole genomes of these strains were isolated and sequenced, and phylogenetic trees were constructed based on the gene sequences in different regions of the EV-B prototype strains. It was found that E33 may be recombined in the P2 and P3 regions. Five genotypes (A-E) were defined based on the entire VP1 region of E33, of which the C gene subtype was the dominant gene subtype at present. Recombinant analysis showed that genotype C strains likely recombined with EV-B80, EV-B85, E13, and CVA9 in the P2 and P3 regions, while genotype E had the possibility of recombination with CVB3, E3, E6, and E4. Results of Bayesian analysis indicated that E33 may have appeared around 1955 (95% confidence interval: 1945-1959), with a high evolutionary rate of 1.11 × 10-2 substitution/site/year (95% highest posterior density (HPD): 8.17 × 10-3 to 1.4 × 10-2 substitution/site/year). According to spatial transmission route analysis, two significant transmission routes were identified: from Australia to India and from Oman to Thailand, which the E33 strain in Mainland of China likely introduced from Mexico and India. In conclusion, our study fills the gaps in the evolutionary analysis of E33 and can provide important data for enterovirus surveillance.

12.
Front Oncol ; 12: 1007305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419874

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignant liver tumors. A homotypic cell-in-cell structure (hoCIC) refers to one or more cells internalized into the same type as their neighbors, which predominantly occurs in multiple tumors. The objective of this study was to investigate the prognostic value of hoCICs in HCC and its relationship with other clinicopathological features. By immunostaining analysis of a panel of HCC tissues, we found that hoCICs were prevalent in tumor tissues (54/90) but not in para-tumor tissues (17/90). The presence of hoCICs in tumor tissues was closely associated with E-cadherin expression. The presence of CICs was identified as significantly associated with poor survival rates of patients with HCC, comparable to traditional clinicopathological parameters, such as histological grade [hazard ratio (HR) = 0.734, p = 0.320]. Multivariate Cox regression analysis further confirmed that CICs were an independent risk factor for poor survival (HR = 1.902, p = 0.047). In addition, hoCICs were the predominant contributor in a nomogram model constructed for survival prediction at 1, 3, and 5 years [the areas under the curve (AUCs) were 0.760, 0.733, and 0.794, respectively]. Stratification analysis indicated that hoCICs tend to selectively affect patients with high-grade disease (HR = 2.477, p = 0.009) and at the early TNM stage (HR = 2.351, p = 0.05). Thus, hoCICs predict poor survival of patients with HCC, particularly those with higher grades and at an early stage.

14.
Front Oncol ; 12: 871786, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330486

RESUMO

Background: Immunotherapy plays an important role in the treatment of triple-negative breast cancer (TNBC). This study aimed to identify immune-related genes that are associated with the prognosis of patients with TNBC as possible targets of immunotherapy, alongside their related tumor-infiltrating lymphocytes (TILs). Methods: The clinical data and gene expression profiles of patients with breast cancer were extracted from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases and divided into training (n = 1,053) and verification (n = 508) groups. CIBERSORT was used to predict the differences in immune cell infiltration in patient subsets that were stratified according to risk. Gene Ontology (GO) enrichment analysis was used to identify pathways associated with immune-related genes in patient subsets that were stratified according to risk. The clinical data and insulin-like growth factor 2 receptor (IGF2R) expression profiles of patients with breast cancer were extracted from METABRIC. The expression of IGF2R and TILs were evaluated in a cohort containing 282 untreated patients with TNBC. The correlations of IGF2R expression, TILs, and clinicopathological parameters with patient prognosis were analyzed in the whole cohort. Results: The prognostic model, which was composed of 26 immune-related gene pairs, significantly distinguished between high- and low-risk patients. Univariate and multivariate analyses indicated that the model was an independent prognostic factor for breast cancer. Among the identified genes, the expression of IGF2R significantly distinguished between high- and low-risk patients in TCGA (P = 0.008) and in METABRIC patients (P < 0.001). The expression of IGF2R was significantly associated with clinical risk factors such as TNBC, estrogen receptor (ER)-negative expression, human epidermal growth factor receptor 2 (HER2)-positive expression, and age ≤60 years old in METABRIC patients. In addition, the patients with IGF2R-positive expression had lower disease-free survival (DFS) rates than those with IGF2R-negative expression in the TNBC cohort (67.8% vs. 78.5%, P = 0.023). IGF2R expression also was significantly negatively correlated with TILs, particularly with CD8+ TILs and CD19+ TILs in the cohort of patients with TNBC. Conclusion: IGF2R can be used as an indicator of a poor prognosis in patients with TNBC and as a potential target and research direction for TNBC immunotherapy in the future.

15.
Front Microbiol ; 13: 967746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212829

RESUMO

Soil microbial organisms are conducive to SOC sequestration. However, little attention has been given to the contributions of living MBC and microbial necromass carbon to the SOC pool under biochar and straw amendments. The aims of the study were to explore (1) the effects of maize straw and biochar on MBC, POC, MAOC, DOC and microbial necromass carbon; (2) the contribution of MBC and microbial necromass carbon to the SOC pool; and (3) the relationships among the soil microbial community structure, microbial necromass carbon and other SOC fractions under maize straw and biochar application for nine consecutive years. Three treatments were studied: CK (applied chemical fertilizer only), BC (biochar applied annually at a rate of 2.625 t ha-1 combined with chemical fertilizer), and SR (straw applied annually at a rate of 7.5 t ha-1). Both biochar and straw increased the SOC contents after nine successive maize plant seasons; the DOC and MAOC contents were also increased by biochar and straw amendments. Biochar had advantages in increasing POC contents compared to straw. Biochar and straw increased MBC contents by 48.54% and 60.83% compared to CK, respectively. Straw significantly increased the Galn, GluN, MurA, ManN and total amino contents (P < 0.05); however, biochar significantly increased the Galn and GluN contents (P < 0.05) but had no impact on the MurA contents and decreased the ManN contents. Biochar mainly increased the fungal-derived necromass carbon contents but had no effect on the bacterial-derived necromass carbon, and straw increased both the bacterial- and fungal-derived necromass carbon contents. Straw had no influence on the ratios of microbial necromass carbon accounting for SOC and MAOC, but biochar decreased the ratios in the current study. Similarly, biochar mainly increased the fungal PLFA and total PLFA contents compared to CK, but straw increased bacterial PLFAs, fungal PLFAs and Actinomycetes PLFAs. Maize yield were increased by 7.44 and 9.16% by biochar and straw application, respectively. These results indicate that biochar stimulates fungal activities and turnover to contribute to the stable soil carbon pool and that biochar also improves POC contents to improve the soil organic carbon sink.

16.
J Oncol ; 2022: 7742035, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213840

RESUMO

Objective: To construct a nomogram-based prediction model for the clinical prognosis of patients with stage II and III colon cancer who underwent Xelox chemotherapy after laparoscopic radical resection based on large data sets. Methods: A total of 7,832 patients with colorectal cancer who received postoperative Xelox-based chemotherapy were screened from the Surveillance, Epidemiology, and End Results database (USA) as the training data set. In addition, 348 domestic patients were screened as the validation data set. Multivariate Cox regression analysis was performed to identify variables for inclusion in the nomogram-based prediction model. The predictive accuracy of the model was assessed using C-index and calibration curve. Results: Age, cell differentiation, nerve invasion, T and N stages of tumours, number of dissected lymph nodes, and carcinoembryonic antigen (CEA) level were found to influence the efficacy of postoperative chemotherapy. The nomogram-based prediction model was successfully constructed. The C-index of both the training set and validation set were higher than those of the 7th edition of TNM staging system published by the American Joint Commission on Cancer (C - index of training data set = 0.728, C - index of validation data set = 0.734). The prediction results of the model in the calibration curve showed a good fit with the actual situation. Conclusion: We successfully constructed a nomogram-based model to predict the clinical prognosis of patients with colorectal cancer receiving postoperative Xelox-based chemotherapy after laparoscopic radical resection, which showed good clinical application value for predicting the efficacy of postoperative Xelox-based chemotherapy in patients with colorectal cancer.

17.
Angew Chem Int Ed Engl ; : e202213296, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280592

RESUMO

Not only high efficiency but also high selectivity of the electrocatalysts is crucial for high-performance, low-cost, and sustainable energy storage applications. Herein, we systematically investigate the edge effect of carbon-supported single-atom catalysts (SACs) on oxygen reduction reaction (ORR) pathways (two-electron (2 e- ) or four-electron (4 e- )) and conclude that the 2 e- -ORR proceeding over the edge-hosted atomic Co-N4 sites is more favorable than the basal-plane-hosted ones. As such, we have successfully synthesized and tuned Co-SACs with different edge-to-bulk ratios. The as-prepared edge-rich Co-N/HPC catalyst exhibits excellent 2 e- -ORR performance with a remarkable selectivity of ≈95 % in a wide potential range. Furthermore, we also find that oxygen functional groups could saturate the graphitic carbon edges under the ORR operation and further promote electrocatalytic performance. These findings on the structure-property relationship in SACs offer a promising direction for large-scale and low-cost electrochemical H2 O2 production via the 2 e- -ORR.

18.
ACS Appl Mater Interfaces ; 14(42): 47882-47891, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36239388

RESUMO

Superatom-based superionic conductors are of current interest due to their promising applications in solid-state electrolytes for rechargeable batteries. However, much less attention has been paid to their thermal properties, which are vital for safety and performance. Motivated by the recent synthesis of superatom-based superionic conductor Na3OBH4 consisting of superhalogen cluster BH4, we systematically investigate its lattice dynamics and thermal conductivity using the density functional theory combined with a self-consistent phonon approach. We reveal the bonding hierarchy features by studying the electron localization function and potential energy surface and further unveil the rattling effect of the BH4 superatom, which introduces strong quartic anharmonicity and induces soft phonon modes in low temperatures by assisting Na displacements, thus calling for the necessity of quartic renormalization and four-phonon scattering in calculating the lattice thermal conductivity. We find that the contribution of four-phonon processes to the lattice thermal conductivity increases from 13 to 32% when the temperature rises from 200 to 400 K. At room temperature (300 K), the phonon scattering phase space is enlarged by 133% due to the four-phonon interactions, and the lattice thermal conductivity is evaluated to be 5.34 W/mK, reduced by 24% as compared with a value of 6.99 W/mK involving three-phonon scattering only. These findings provide a better understanding of the lattice stability and thermal transport properties of superionic conductor Na3OBH4, shedding light on the role of strong quartic anharmonicity played in superatom-based materials.

19.
Hum Vaccin Immunother ; : 2132802, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36287462

RESUMO

This study aimed to develop a consensus framework for economic evaluations of vaccines as a national guideline in China. Some unique and important aspects were particularly emphasized. Nineteen Chinese experts in the field of health economics and immunization decision-making were nominated to select and discuss relevant aspects of vaccine economic evaluations in China. A workshop attended by external experts was held to summarize unique and important aspects and formulate consensus recommendations. There were ten unique and/or important aspects identified for economic evaluations of vaccines in China, including study perspectives, comparator strategies, analysis types, model choices, costing approaches, utility measures, discounting, uncertainty, equity, and evaluation purposes. Background information and expert recommendations were provided for each aspect. Economic evaluations of vaccines should play an important role in China's immunization policy-making. This guideline can help improve the quality of economic evaluations as a good practice consensus.

20.
Front Psychol ; 13: 873770, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312180

RESUMO

Objectives: More and more countries have decided to cancel most or even all COVD-19 restrictions. However, it is unclear how ending of restrictions will affect primary care providers' job satisfaction and organizational commitment. Our objectives are to explore the current status and possible change in primary care providers' job satisfaction and organizational commitment after massive restriction policies ended in China. Methods: This was a mixed-method study that utilized structured questionnaires and semi-structured qualitative individual interviews. The 20-item Minnesota Satisfaction Questionnaire (MSQ) and 25-item organizational commitment survey were adopted to assess job satisfaction and organization commitment. Descriptive statistics and mediation models, as well as inductive thematic analysis, were used to analyze quantitative and qualitative data. Results: A total of 18 interviews and 435 valid survey responses were included in our analysis. The average scores for job satisfaction and organizational commitment were 80.6 and 90.8. The thematic analysis revealed one major theme: ethical and moral responsibility to provide care as primary care providers, on which we established a mediation model. The mediation analysis revealed that normative commitment could positively affect the other four dimensions of organizational commitment and job satisfaction. The direct effect of affective commitment on job satisfaction was significant (LLCI = 0.11, ULCI = 0.31), and the mediators were identified to have a partial mediating effect instead of a total mediating effect. Conclusion: After COVID-19 restrictions end, the job satisfaction and organizational commitment of primary care providers will return to levels before the pandemic and during this estimated process, a brief rise in resignation is predictable. The normative commitment positively affects the other four dimensions of organizational commitment and job satisfaction for primary care providers, which suggests a possible way to motivate primary care providers when restrictions end.

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