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1.
ACS Appl Mater Interfaces ; 15(38): 44827-44838, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37713509

RESUMEN

Developing bifunctional electrocatalysts with low-content noble metals and high activity and stability is crucial for water splitting. Herein, we reported a novel Ru doped FeP4/Fe2PO5 heterogeneous interface catalyst (Ru@FeP4/Fe2PO5) for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) by heat treatment coupling electrodeposition strategy. Experiments disclosed that Ru@FeP4/Fe2PO5 proclaimed excellent catalytic activity for the OER (249 mV@100 mA cm-2) and HER (49 mV@10 mA cm-2) in a 1 M KOH environment. More importantly, the mass activity and turnover frequency of Ru@FeP4/Fe2PO5 were 117 and 108 times higher than that of commercial RuO2 at an overpotential of 300 mV during the OER, respectively. In addition, the assembled Ru@FeP4/Fe2PO5 || Ru@FeP4/Fe2PO5 system could retain superior durability in a two-electrode system for 134 h at 300 mA cm-2. Further mechanism studies revealed that Ru atoms in Ru@FeP4/Fe2PO5 act in a key role for the excellent activity during water splitting because the electronic structure of Ru sites could be optimized by the interaction between Ru and Fe atoms at the interface to strengthen the adsorption of reaction intermediates. Besides, the introduction of Ru atoms could also enhance the charge transfer, which effectually accelerates the reaction kinetics. The strategy of anchoring Ru atom on novel heterostructure provides a promising path to boost the overall activity of electrocatalysts for water splitting.

2.
Polymers (Basel) ; 15(15)2023 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-37571210

RESUMEN

Anthocyanins (ANs) have strong antioxidant activities and can inhibit chronic diseases, but the instability of ANs limits their applications. The conservation of preheating whey protein concentrate (WPC) on the stability of purple sweet potato ANs was investigated. The retention of ANs in WPC-ANs was 85.88% after storage at 25 °C for 5 h. WPC-ANs had higher retention of ANs in heating treatment. The retention rates of ANs in WPC-ANs exposed to light and UV lamps for 6 h were 78.72% and 85.76%, respectively. When the concentration of H2O2 was 0.50%, the retention rate of ANs in the complexes was 62.04%. WPC-ANs' stability and antioxidant activity were improved in simulated digestive juice. The WPC-ANs connection was static quenching, and the binding force between them was a hydrophobic interaction at one binding site, according to the fluorescence quenching spectroscopy. UV-visible absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR) analysis further indicated that the secondary structure and microenvironment of amino acid residues in WPC can be impacted by the preheating temperature and preheating times of WPC. In conclusion, preheating WPC can successfully preserve the stability of purple sweet potato ANs by binding to them through a non-covalent interaction.

3.
Comput Biol Med ; 159: 106898, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37062253

RESUMEN

Based on the generalized Darcy model, here we develop a linear one-dimensional (1D) composite model to predict the effects of the inserted balloon under REBOA operations on the dynamic characteristics of blood flow in flexible arterial networks. We first consider the effect of the decrease of cardiac output under different degrees of blood loss through employing the fourth-order lumped parameter model of cardiovascular system. Then, the effect of the inserted balloon is included by developing the relation between flow resistance and occlusion ratio with the neural network approach. Finally, the accuracy of the developed 1D composite model for REBOA operations, which can be solved analytically in the frequency domain, is verified by comparing to computational fluid dynamics (CFD) simulations. It is demonstrated that the 1D model is able to reproduce main features of the systemic circulation under balloon occlusion of the aorta during REBOA surgery. The 1D composite model could substantially reduce the computational time, which makes it possible to give the instant prediction of the working parameters during RABOA operations.


Asunto(s)
Oclusión con Balón , Procedimientos Endovasculares , Humanos , Resucitación/métodos , Hemodinámica/fisiología , Hemorragia , Aorta/cirugía , Flujo Pulsátil , Oclusión con Balón/métodos , Procedimientos Endovasculares/métodos
4.
Am J Transl Res ; 15(1): 138-150, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36777859

RESUMEN

BACKGROUND: MicroRNAs (miRNAs) play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, the molecular mechanisms underlying the function of miRNAs remain to be fully understood. This study aimed to explore the profile of serum exosome-derived miRNAs in the rat model of COPD. METHODS: We established the COPD rat model by cigarette smoke exposure (CSE). The pulmonary function and morphological changes were analyzed. Serum exosomes were examined by transmission electron microscopy (TEM) and western blotting. The differentially expressed miRNAs between COPD and healthy rats were screened from exosome-derived small RNA library using bioinformatics analysis and experimentally verified in rat lung tissues by quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: The pulmonary function indexes in COPD rats were significantly decreased compared to control rats. The typical pathological manifestations of emphysema were observed in COPD rats. Marker proteins (CD9, CD63, and TSG101) and characteristic morphology features were detected in serum exosomes. Fifteen differentially expressed miRNAs were identified in the small RNA library. In addition, we confirmed that the expression of miR-185-5p and miR-182-5p was significantly down-regulated in the lung tissues of COPD rats compared to control rats. CONCLUSION: The expression of miR-185-5p and miR-182-5p was down-regulated in serum-derived exosomes and lung tissues of COPD rats, indicating that these two miRNAs might be involved in the development of COPD and might serve as potential biomarkers for the diagnosis of COPD.

5.
J Colloid Interface Sci ; 629(Pt A): 53-62, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36049329

RESUMEN

Regulating catalyst composition is one of the efficient approaches to boost intrinsic activity of electrocatalysts for water splitting. Herein, four different hollow porous platinum-copper (PtCu) nanotubes (NTs) with controllable compositions were precisely fabricated by a facile wet-chemistry method. Importantly, Pt5Cu2 NTs display the best hydrogen evolution reaction (HER) performance in all pH conditions compared to other samples, which just require overpotentials of 34 ± 2, 32 ± 2, and 284 ± 2 mV at 10 mA cm-2 in basic, acidic, and neutral solutions, respectively. Moreover, Pt5Cu2 NTs also exhibit outstanding stability and corrosion resistance in all pH ranges. Then, mechanism analysis reveals that the electronic structure of Pt sites is regulated by changing the ratio of Pt and Cu, which directly optimizes the binding energy of reaction intermediates and promotes electron transfer during the HER process. In addition, a porous nanotube structure with countless nanoparticles on the surface provides a large number of active sites, enhancing the adsorption/desorption of reactants. This work emphasizes the importance of catalyst composition and provides a highly active potential HER catalyst for practical hydrogen production.

6.
Front Cell Infect Microbiol ; 12: 977591, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36275015

RESUMEN

Background: Timely identification of causative pathogens is important for the diagnosis and treatment of pulmonary infections. Metagenomic next-generation sequencing (mNGS), a novel approach to pathogen detection, can directly sequence nucleic acids of specimens, providing a wide range of microbial profile. The purpose of this study was to evaluate the diagnostic performance of mNGS in the bronchoalveolar lavage fluid (BALF) of patients with suspected pulmonary infection. Methods: From April 2019 to September 2021, 502 patients with suspected pneumonia, who underwent both mNGS of BALF and conventional microbiological tests (CMTs), were classified into different groups based on comorbidities. The diagnostic performances of mNGS and CMTs were compared. Comprehensive clinical analysis was used as the reference standard. Results: The diagnostic accuracy and sensitivity of mNGS were 74.9% (95% confidence interval [CI], 71.7-78.7%) and 72.5% (95% CI, 68.2-76.8%) respectively, outperformed those of CMTs (36.9% diagnostic accuracy, 25.4% sensitivity). For most pathogens, the detection rate of mNGS was higher than that of CMTs. Polymicrobial infections most often occurred in immunocompromised patients (22.1%). Only 2.3% patients without underlying diseases developed polymicrobial infections. Additionally, the spectrums of pathogens also varied among the different groups. We found the positive predictive values (PPV) to be dependent upon both the pathogen of interest as well as the immunologic status of the patient (e.g., the PPV of Mycobacterium tuberculosis was 94.9% while the PPV of Pneumocystis jirovecii in immunocompetent individuals was 12.8%). This information can help physicians interpret mNGS results. Conclusion: mNGS of BALF can greatly enhance the accuracy and detection rate of pathogens in patients with pulmonary infections. Moreover, the comorbidities and types of pathogens should be taken consideration when interpreting the results of mNGS.


Asunto(s)
Coinfección , Ácidos Nucleicos , Neumonía , Humanos , Estudios Retrospectivos , Coinfección/microbiología , Sensibilidad y Especificidad , Metagenómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neumonía/diagnóstico , Neumonía/microbiología
7.
ACS Appl Mater Interfaces ; 12(8): 9600-9608, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32027803

RESUMEN

Developing highly active and durable electrocatalysts with low levels of Pt content toward some crucial reactions including oxygen reduction reaction, hydrogen evolution reaction, and methanol oxidation reaction in an acidic electrolyte environment are desirable but still an open challenge for clean and efficient energy conversion. Herein, we present a facile route to synthesize low Pt-content ternary PtNiCu nanostructures with hollow interior and accessible surfaces (H-PtNiCu-AAT NPs) as enhanced multifunctional electrocatalysts. The galvanic replacement reaction and atomic diffusion between in situ preformed CuNi nanocrystals and Pt species should be responsible for the formation of hollow PtNiCu NPs. Continuous activation by acid picking and annealing treatments were performed to leach out the excessive Cu and Ni on the surfaces and to enrich Pt-content on the surface. H-PtNiCu-AAT NPs exhibit excellent activity and durability toward HER, ORR, and MOR due to the rational integration of multiple structural advantages. Strikingly, the mass activity and specific activity of H-PtNiCu-AAT NPs (0.977 A mgPt-1 and 1.458 mA cm-2) is 7.1 and 6.9 times higher than that of commercial Pt/C (0.138 A mgPt-1 and 0.212 mA cm-2) toward ORR at 0.9 V (vs RHE), respectively. This present work provides an efficient strategy for the design of low Pt-content trimetallic electrocatalysts with excellent activity and durability.

8.
Chaos ; 29(9): 093122, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31575120

RESUMEN

We present a method to learn mean residence time and escape probability from data modeled by stochastic differential equations. This method is a combination of machine learning from data (to extract stochastic differential equations as models) and stochastic dynamics (to quantify dynamical behaviors with deterministic tools). The goal is to learn and understand stochastic dynamics based on data. This method is applicable to sample path data collected from complex systems, as long as these systems can be modeled as stochastic differential equations.

9.
PLoS One ; 14(2): e0213243, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30811504

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0194915.].

10.
PLoS One ; 13(4): e0194915, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29634779

RESUMEN

This study aimed to locate the contributing factors of Catastrophic Health Expenditure (CHE), evaluate their impacts, and try to propose strategies for reducing the possibilities of CHE in the context of China's current public health insurance system. The financial data of all hospitalization cases from a sample hospital in 2013 were gathered and used to determine the pattern of household medical costs. A simulation model was constructed based on China's current public health insurance system to evaluate the financial burden for medical service on Chinese patients, as well as to calculate the possibilities of CHE. Then, by adjusting several parameters, suggestions were made for China's health insurance system in order to reduce CHE. It's found with China's current public health insurance system, the financial aid that a patient may receive depends on whether he is from an urban or rural area and whether he is employed. Due to the different insurance policies and the wide income gap between urban and rural areas, rural residents are much more financially vulnerable during health crisis. The possibility of CHE can be more than 50% for low-income rural families. The CHE ratio can be dramatically lowered by applying different policies for different household income groups. It's concluded the financial burden for medical services of Chinese patients is quite large currently, especially for those from rural areas. By referencing different healthcare policies in the world, applying different health insurance policies for different income groups can dramatically reduce the possibility of CHE in China.


Asunto(s)
Costos de la Atención en Salud , Seguro de Salud/economía , Programas Nacionales de Salud/economía , China , Simulación por Computador , Toma de Decisiones , Economía Hospitalaria , Teoría del Juego , Reforma de la Atención de Salud , Investigación sobre Servicios de Salud , Hospitalización/economía , Humanos , Pobreza , Salud Pública , Población Rural , Teoría de Sistemas , Población Urbana
11.
J Colloid Interface Sci ; 507: 429-436, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28806662

RESUMEN

The development of highly efficient and non-noble catalysts for both the reduction of 4-nitrophenol (4-NP) and NaBH4 hydrolysis is extraordinary attractive but it remains a tremendous challenge. In this work, self-assembled porous Co2P nanowires (NWs) have been successfully prepared via the low-temperature hydrothermal method and the comprehensive experiments validate that the sample is a high efficient bifunctional catalyst for both the reduction of 4-nitrophenol and sodium borohydride hydrolysis. Specifically, the as-prepared porous Co2P NWs exhibit more excellent catalytic performance (knor=743s-1g-1) than that of other reported catalysts towards reduction of 4-nitrophenol. The catalytic activity of sodium borohydride hydrolysis is also investigated and the Co2P NWs show superior hydrogen generation rate (4028mLmin-1g-1) at 30°C for sodium borohydride hydrolysis. Our results indicate that porous Co2P nanowires possess a potential application on both the sodium borohydride hydrolysis and reduction of 4-nitrophenol.

12.
ACS Appl Mater Interfaces ; 9(23): 19843-19851, 2017 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-28537715

RESUMEN

The design and development of low-cost Pt-free, high-active, and durable noble-metal-free electrocatalysts for methanol electrooxidation is highly desirable but remains a challenge. Herein, unique Cu/NiCu nanowires (NWs) integrating alloy, core-shell, and one-dimensional structures are prepared by a facile one-pot strategy. It is found that the Ni-Cu surface alloying structure can effectively change the charge distribution of the atomic configuration, the core-shell structure can be optimized with the usage of Ni and Cu, and the one-dimensional structure can effectively enhance the charge transfer between the electrode surface and the active sites, making the prepared NWs promising electrocatalysts. Detailed catalytic investigations showed that the obtained Cu/NiCu NWs exhibit an enhanced electrocatalytic performance for methanol oxidation reaction (MOR). The optimized Cu/NiCu NWs in this work show a mass current density of 867.1 mA mgmetal-1 at 1.55 V (vs. RHE) for MOR, which is far higher than those of Ni-based previously reported electrocatalysts. This work opens up a new pathway for the design and engineering of noble-metal-free alloy electrocatalysts with enhanced activity and durability.

13.
Int J Telemed Appl ; 2017: 1503298, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28293258

RESUMEN

Reform of drug procurement is being extensively implemented and expanded in China, especially in today's big data environment. However, the pattern of supply mode innovation lags behind procurement improvement. Problems in financial strain and supply break frequently occur, which affect the stability of drug supply. Drug Pooling System is proposed and applied in a few pilot cities to resolve these problems. From the perspective of supply chain, this study analyzes the process of setting important parameters and sets out the tasks of involved parties in a pooling system according to the issues identified in the pilot run. The approach is based on big data analysis and simulation using system dynamic theory and modeling of Vensim software to optimize system performance. This study proposes a theoretical framework to resolve problems and attempts to provide a valuable reference for future application of pooling systems.

14.
Nanotechnology ; 27(49): 495403, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27827341

RESUMEN

In order to combine the advantages of both 0D and 1D nanostructured materials into a single catalyst, density functional theory (DFT) calculations have been used to study the PdCu alloy NP-decorated Cu nanotubes (PdCu@CuNTs). These present a significant improvement of the electrocatalytic activity of formic acid oxidation (FAO). Motivated by our theoretical work, we adopted the seed-mediated growth method to successfully synthesize the nanostructured PdCu@CuNTs. The new catalysts triple the catalytic activity for FAO, compared with commercial Pd/C. In summary, our work provides a new strategy for the DFT prediction and experimental synthesis of novel metal NP-decorated 1D nanostructures as electrocatalysts for fuel cells.

15.
Microbiol Res ; 166(3): 155-60, 2011 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-20630726

RESUMEN

Strain BJ-L was isolated from the a water sample taken from Xiao Yue River in Beijing and identified as Acinetobacter sp. BJ-L based on the study of its morphology, physiology, biochemistry and 16S rRNA gene sequence. A new antimicrobial substance was produced after the strain was incubated in potato extract medium at 15°C for 72 h. The antimicrobial substance was sequentially purified by reduced pressure condensation, EtOAc extract, and silica gel column chromatography. The structure of the antimicrobial substance was elucidated as succinamide conjugate diacid (SCD) by spectroscopic data interpretation. Structure analysis indicated that SCD is a novel compound and that it could inhibit the growth of some tested bacterial strains with the MIC of 2mg/ml, such as Staphylococcus aureus, Bacillus subtilis, Enterobacter aerogenes and Escherichia coli. Moreover, no obvious toxicity has been found on cultured HUVEC cells with different concentrations of SCD at 5, 10, 15, and 20mg/ml.


Asunto(s)
Acinetobacter/enzimología , Amidas , Antibacterianos , Succinimidas , Acinetobacter/clasificación , Acinetobacter/genética , Acinetobacter/aislamiento & purificación , Amidas/química , Amidas/aislamiento & purificación , Amidas/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Células Cultivadas , ADN Ribosómico/genética , Células Endoteliales/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , ARN Ribosómico 16S/genética , Succinato Deshidrogenasa/metabolismo , Succinatos , Succinimidas/química , Succinimidas/aislamiento & purificación , Succinimidas/farmacología
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