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1.
Nat Commun ; 15(1): 2166, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461211

RESUMEN

Achieving selective hydrodeoxygenation of α, ß-unsaturated carbonyl groups to alkenes poses a substantial challenge due to the presence of multiple functional groups. In this study, we develop a ZnNC-X catalyst (X represents the calcination temperature) that incorporates both Lewis acidic-basic sites and Zn-Nx sites to address this challenge. Among the catalyst variants, ZnNC-900 catalyst exhibits impressive selectivity for alkenes in the hydrodeoxygenation of α, ß-unsaturated carbonyl compounds, achieving up to 94.8% selectivity. Through comprehensive mechanism investigations and catalyst characterization, we identify the Lewis acidic-basic sites as responsible for the selective hydrogenation of C=O bonds, while the Zn-Nx sites facilitate the subsequent selective hydrodeoxygenation step. Furthermore, ZnNC-900 catalyst displays broad applicability across a diverse range of unsaturated carbonyl compounds. These findings not only offer valuable insights into the design of effective catalysts for controlling alkene selectivity but also extend the scope of sustainable transformations in synthetic chemistry.

2.
J Colloid Interface Sci ; 650(Pt B): 2014-2023, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37531668

RESUMEN

In recent years, electromagnetic pollution has become more and more serious, and there is an urgent need for microwave absorbing materials with superior performance. Prussian blue analogue (PBA) is a metal organic framework material with the advantages of diverse morphology and tunable composition. Therefore, PBA has attracted a lot of attention in the field of microwave absorption. In this work, PBA was coated on the surface of carbon composites by hydrothermal method, and then PPy was compounded on its surface after carbonization treatment to construct hierarchical core-shell CoC@CoFe/C@PPy fibers. The fibers have Co-doped C composites as the core and CoFe/C decorated with PPy as the shell. This unique hierarchical structure and various microwave absorption mechanisms are described in detail. The microwave absorption performance is optimized by adjusting the filling of the sample. The best microwave absorption performances are achieved at 25 wt% filling of CoC@CoFe/C@PPy. At a thickness of just 1.69 mm, CoC@CoFe/C@PPy fiebrs have a minimum reflection loss (RLmin) of -64.32 dB. When the thickness is 1.88 mm, CoC@CoFe/C@PPy achieves a maximum effective absorption bandwidth (EABmax) of 5.38 GHz. The results indicate that the CoC@CoFe/C@PPy composite fibers have a great potential in the field of microwave absorption.

3.
Dalton Trans ; 52(25): 8503-8529, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37312618

RESUMEN

Gas sensors are essential for detecting toxic gases that can harm social life or industrial production. Traditional metal oxide semiconductor (MOS)-based sensors suffer from shortcomings such as high operating temperature and slow response time, which limits their detection capabilities. Thus, there is a need to improve their performance. One useful technique is noble metal functionalization, which can effectively enhance the response/recovery time, sensitivity and selectivity, sensing response, and optimum operating temperature of MOS gas sensors. Among the noble metals, Au NPs are considered a promising material for forming composite sensing materials to achieve better sensing performance. This paper aims to review and discuss the recent research on Au-decorated MOS-based sensors, including Au/n-type MOS-based sensors, Au/p-type MOS-based sensors, Au/MOS/carbon composite materials, and Au/MOS/perovskite composite materials. The sensing mechanism of Au-functionalized MOS-based materials will also be examined.

4.
Nat Commun ; 13(1): 2320, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35484152

RESUMEN

Designing heterogeneous solid surface frustrated Lewis pair (ssFLP) catalyst for hydrogenation is a new challenge in catalysis and no research has been reported on the construction of ssFLP on boehmite (AlOOH) surfaces up to now as far as we know. Herein, AlOOH with a layer structure is prepared and it is found that the Lewis basic OHv site (one H removed from OH) and an adjacent Lewis acidic unsaturated Al site (Al3+unsatur.) proximal to a surface OHv (OH vacancy) on AlOOH layers could form the ssFLP. The layered structure of AlOOH and its abundant OH defects over the surface result in a high concentration of OHv/Al3+unsatur. FLPs, which are conducive to highly efficient hydrogen activation for hydrogenation of olefins and alkynes with low H-H bond dissociates activation energy of 0.16 eV under mild conditions (T = 80°C and P(H2) = 2.0 MPa). This work develops a new kind of hydrogenation catalyst and provides a new perspective for creating solid surface FLP.

5.
Am J Nephrol ; 53(2-3): 129-138, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35272286

RESUMEN

INTRODUCTION: Anti-phospholipase A2 receptor antibody (PLA2R-Ab) is highly specific for primary membranous nephropathy (PMN). Here, we compare the diagnostic value of different circulating PLA2R-Ab cutoff titers in multicenter cohorts, with particular focus on determining the optimal cutoff value for Chinese patients. METHODS: In total, 288 patients with PMN and 301 with other nephropathies were recruited retrospectively from five hospitals in China between September 2011 and October 2018. PLA2R-Ab in serum obtained at renal biopsy was determined by enzyme-linked immunosorbent assay. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) curve of PLA2R-Ab in diagnosing PMN were assessed. Diagnostic efficiency was evaluated by internal validation. RESULTS: The sensitivity, specificity, PPV, NPV, and Youden index for PMN diagnosis were 71%, 90%, 88%, 75%, and 0.61 at the cutoff of 3.8 RU/mL; 74%, 86%, 84%, 76%, and 0.60 at 2.7 RU/mL; 68%, 92%, 90%, 73%, and 0.60 at 5.2 RU/mL; 64%, 95%, 93%, 72%, and 0.59 at 9.0 RU/mL; 57%, 96%, 94%, 68%, and 0.54 at 14.0 RU/mL; 51%, 97%, 95%, 66%, and 0.49 at 20.0 RU/mL; 47%, 98%, 96%, 64%, and 0.45 at 40.0 RU/mL, respectively. The area under the ROC curve was 0.83. CONCLUSION: By comprehensively considering specificity and sensitivity, we show that 3.8 RU/mL is the optimal cutoff of PLA2R-Ab in Chinese PMN patients, with a sensitivity of 71% and a specificity of 90%. The cutoff values were 5.2 RU/mL and 9.0 RU/mL when the diagnostic specificity was increased to 92% and 95%, respectively.


Asunto(s)
Glomerulonefritis Membranosa , Autoanticuerpos , Ensayo de Inmunoadsorción Enzimática , Humanos , Curva ROC , Receptores de Fosfolipasa A2 , Estudios Retrospectivos
6.
Accid Anal Prev ; 144: 105613, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32544671

RESUMEN

Bicycle wrong way riding (WWR) is a dangerous and often neglected behavior that engenders threats to traffic safety. Owing to the lack of exposure data, the detection of WWR and its relationship with the built environment (BE) factors remain unclear. Accordingly, this study fills the research gaps by proposing a WWR detection framework based on bike-sharing trajectories collected from Chengdu, China. Moreover, this study adopts Negative Binomial-based Additive Decision Tree to investigate the impacts of built environment on WWR frequencies. Results reveal that (1) WWR distribution is unaffected by different periods in a day; (2) road length is more influential than road level and road direction in WWR occurrence; (3) company, bus stop, subway station, residence, and catering facility are primary contributors affecting WWR behavior during peak hours, whereas education becomes an emerging influential variable during nonpeak hours; and most importantly, (4) these variables clearly present non-linear effects on the WWR frequencies. Therefore, geographically differentiated policies should be adopted for bicycle safety improvement.


Asunto(s)
Ciclismo/estadística & datos numéricos , Entorno Construido/estadística & datos numéricos , Accidentes de Tránsito/prevención & control , Ciclismo/psicología , Entorno Construido/normas , China , Femenino , Humanos , Masculino
7.
Int J Biol Macromol ; 132: 954-962, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30974135

RESUMEN

A high-performance superabsorbent hydrogel have been successfully fabricated by using waste hemicelluloses lye. Not any extra base was added into the synthesis system for achieving hydrophilic polymer composite. In addition, polyvinyl alcohol (PVA) was added the reaction system to entrap within the hemicelluloses-g-AA/bentonite matrix and form a semi-interpenetrating polymer networks (semi-IPN) for enhancing the swelling properties of the as-prepared polymer composite. SEM, FTIR, and TG were employed to characterize the morphologies, structure, and thermal stability of as-synthesized hydrogel composite. Moreover, liquid absorbency in distilled water and saline solutions, water absorption rate, water retainability, and water reusability of hemicelluloses-g-AA/bentonite (HAB) and hemicelluloses-g-AA/bentonite-PVA (HAB-PVA) hydrogels were also investigated systematically. The adsorption kinetics and isotherms of the composites were studied, and the synergy effect of PVA and bentonite were also proposed. This method provides a new avenue to design the new structure of superabsorbent hydrogel and treat the waste lye in green and sustainable chemical engineering processes.


Asunto(s)
Absorción Fisicoquímica , Hidrogeles/química , Hidrogeles/síntesis química , Lejía/química , Polisacáridos/química , Residuos/análisis , Bentonita/química , Técnicas de Química Sintética , Concentración de Iones de Hidrógeno , Alcohol Polivinílico/química , Agua/química
8.
J Cell Biochem ; 120(2): 1444-1456, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30414207

RESUMEN

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with unknown etiology. Nowadays, several long noncoding RNAs (lncRNAs) have been reported as molecular alterations involved in SLE. This study aimed to reveal the function of TNF-related and HNRNPL-related immunoregulatory lncRNA (THRIL) in SLE. Human epithelial HK-2 cells were exposed to lipopolysaccharide (LPS) to mimic an in vitro SLE model. Then, the functions of THRIL, miR-34a, and monocyte chemoattractant protein-1 (MCP-1), as well as their correlations were detected. LncRNA THRIL was highly expressed in the LPS-stimulated cells, and THRIL overexpression aggravated LPS-induced cell damage as cell viability was decreased, and apoptosis and the release of proinflammatory cytokines were increased. THRIL worked as a sponge of microRNA-34a (miR-34a) and it could directly target MCP-1. Furthermore, MCP-1-activated JNK and Wnt/ß-catenin signaling pathways. In conclusion, this study suggested that lncRNA THRIL might be a key regulator participating in LPS-induced injury in HK-2 cells. THRIL overexpression aggravated LPS-induced injury possibly via sponging miR-34a, and thus preventing MCP-1 from degradation by miR-34a. The THRIL/miR-34a/MCP-1 axis might play critical roles in SLE.

9.
Langmuir ; 34(12): 3642-3653, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29478318

RESUMEN

Gold nanoparticles confined into the walls of periodic mesoporous organosilicas (PMOs) with controllable morphology have been successfully fabricated through a one-pot method by using different CO2 pressures. The synthesis can be easily conducted in a mixed aqueous solution by using HAuCl4 as gold source and bis[3-(triethoxysilyl)propyl] tetrasulfide and tetramethoxysilane as the organosilica precursor. P123 and compressed CO2 served as the template and catalytic/regulative agent, respectively. Transmission electron microscopy, N2 adsorption, and X-ray diffraction were employed to characterize the structure of the obtained composite materials. To further investigate the formation mechanism, a series of ordered PMOs with one-dimensional nanotube, two-dimensional hexagonal, vesicle-like, and cellular foam structures were obtained by using different CO2 pressures without the gold source. The mechanism for mesostructure evolution of PMOs with different CO2 pressures was proposed and discussed in detail. The catalytic performance of Au-based PMOs was evaluated for the reduction of 4-nitrophenol (4-NP). These obtained composites with different mesostructures not only exhibit excellent catalytic activity, high conversion rate, and remarkable thermal stability, but they also exhibit morphology-dependent reaction properties in the reduction of 4-NP. The possible reaction pathway of the reactants to embedded Au active sites was proposed and schemed.

10.
Nephrology (Carlton) ; 23(11): 997-1006, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28869321

RESUMEN

AIM: The purpose was to screen potential targets of IFN-K-immunosuppressive therapy, which was used to offer effective information and resources for molecular targeted therapy. METHODS: The gene expression profile of GSE72747 was used to screen out significant differently expressed genes (DEGs). Series Test of Cluster (STC) analysis for DEGs was performed. For all DEGs, the Database for Annotation, Visualization, and Integrated Discovery was performed for Gene Ontology (GO) enrichment analysis. Pathway enrichment analysis of DEGs was performed based on Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Pathway was constructed based on the interactions in the KEGG database. The coexpression network and gene signal expression networks were constructed and analyzed. RESULTS: A total of 2193 DEGs were screened and eight significant profiles were identified. Significant GO terms included small molecule metabolic process, translation and apoptotic process. Metabolic pathways and Alzheimer's disease were significant KEGG pathways. Pathway relationship network of DEGs was constructed. MAPK signalling pathway, apoptosis and pathways in cancer were hub nodes. Gene co-expression network analysis was performed. VCP-interacting membrane protein and NADH dehydrogenase (ubiquinone) 1, alpha/beta subcomplex, 1, 8 kDa were the hub nodes. Gene signal network was constructed with 162 nodes and 254 edges. Hub nodes were phospholipase C, beta 2. CONCLUSION: Screened DEGs including VIMP, NDUFAB1, SEC61G, PSMC2 might be potential targets for lupus nephritis treatment by involving in different functions and pathways, such as metabolic process and immune process.


Asunto(s)
Inmunosupresores/uso terapéutico , Interferón Tipo I/uso terapéutico , Nefritis Lúpica/tratamiento farmacológico , Adulto , Análisis por Conglomerados , Femenino , Ontología de Genes , Humanos , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Selenoproteínas/genética
11.
Sensors (Basel) ; 17(10)2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28934164

RESUMEN

Issues of missing data have become increasingly serious with the rapid increase in usage of traffic sensors. Analyses of the Beijing ring expressway have showed that up to 50% of microwave sensors pose missing values. The imputation of missing traffic data must be urgently solved although a precise solution that cannot be easily achieved due to the significant number of missing portions. In this study, copula-based models are proposed for the spatial interpolation of traffic flow from remote traffic microwave sensors. Most existing interpolation methods only rely on covariance functions to depict spatial correlation and are unsuitable for coping with anomalies due to Gaussian consumption. Copula theory overcomes this issue and provides a connection between the correlation function and the marginal distribution function of traffic flow. To validate copula-based models, a comparison with three kriging methods is conducted. Results indicate that copula-based models outperform kriging methods, especially on roads with irregular traffic patterns. Copula-based models demonstrate significant potential to impute missing data in large-scale transportation networks.

12.
Soft Matter ; 13(34): 5704-5713, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28748980

RESUMEN

A systematic study on the structural properties and component information of periodic mesoporous organosilicas synthesized by using different nonionic surfactants as templates with compressed CO2 was carried out. Triblock copolymers (F127, F108, and P123), oligomeric alkyl poly(ethylene oxide) (Brij-58 and Brij-76), and alkyl-phenol poly(ethylene oxide) (TX-100) have been employed as templates and BTEB as a bridged organosilica precursor to synthesize PMO materials at 5.90 MPa. The structure and morphology of the obtained materials were investigated by means of transmission electron microscopy (TEM), nitrogen sorption isotherms, solid Si and C NMR, and FTIR. Efforts have also been made to compare the differences in structural and morphological properties among these samples synthesized under similar conditions. We also investigate the synthesis of PMOs using F127 as the template at different CO2 pressures. It was found that the interaction between different organic silica precursors and surfactants with a variety of hydrophilic and hydrophobic chains is the key factor for the disorder degree of mesostructures. On this basis, the possible mechanism of formation of PMOs synthesized using a nonionic surfactant (triblock copolymer) as the template with compressed CO2 is illustrated and discussed.

13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(5): 821-5, 2009 Sep.
Artículo en Chino | MEDLINE | ID: mdl-19950591

RESUMEN

OBJECTIVE: To investigate the effects of Artesunate on expression of MCP-1 and MCP-1 mRNA in renal tissue of the rat experimental IgA nephropathy model. METHODS: 40 rats were divided randomly into 4 groups with 10 rats in normal control group while the other 30 in model control group, low dose Artesunate group and high dose Artesunate group after the establishment of IgA nephropathy model. MCP-1 and MCP-1 mRNA in renal tissue were tested by immunohistochemical and RT-PCR methods. RESULTS: The expression of MCP-1 mRNA in model control group was significantly increased (0.4726+/-0.086 vs 0.1445+/-0.095, P<0.05, compared with normal control group), which was suppressed in low dose Artesunate group (0.2844+/-0.065) and high dose Artesunate group (0.2184+/-0.058) (both P<0.05, compared with model control group). In addition, hemouria, proteinuria and pathological changes in renal tissue were improved in the Artesunate groups. CONCLUSION: Artesunate shows the ability of downregulating the expression of MCP-1 in renal tissue, which may explain one of the mechanisms of Artesunate effectiveness in clinical treatment of IgA nephropathy.


Asunto(s)
Artemisininas/farmacología , Quimiocina CCL2/metabolismo , Glomerulonefritis por IGA/metabolismo , Riñón/metabolismo , Animales , Artesunato , Quimiocina CCL2/genética , Regulación hacia Abajo/efectos de los fármacos , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
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