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1.
J Org Chem ; 87(16): 10698-10709, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35930467

RESUMO

Employing a low loading of the terminal oxidant, a remote directing group-enabled radical relay strategy for benzylic direct C(sp3)-H alkoxylation with alcohols at room temperature is developed. Satisfactory site-selectivity, chemoselectivity, and reaction scope are achieved under simple and mild conditions, and no ligand or additive is required. Mechanistic studies, ready conversions of the directing group, and other benzylic functionalizations currently under development in our laboratory further indicate the promising potentials of this remote directing group-enabled radical relay strategy.


Assuntos
Etanol , Benzeno/química , Catálise , Temperatura
2.
Ultrason Sonochem ; 108: 106964, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38943849

RESUMO

Hydrodynamic cavitation (HC) has emerged as a promising technology for water disinfection. Interestingly, when subjected to specific cavitation pressures, jet pump cavitation reactors (JPCRs) exhibit effective water treatment capabilities. This study investigated the cavitation flow and vorticty transport in a JPCR with various area ratios by utilizing computational fluid dynamics. The results reveal that cavitation is more likely to occur within the JPCR as the area ratio becomes smaller. While as the area ratio decreases, the limit flow ratio also decreases, leading to a reduced operational range for the JPCR. During the cavitation inception stage, only a few bubbles with limited travel distances are generated at the throat inlet. A stable cavitation layer developed between the throat and downstream wall during the limited cavitation stage. In this phase, the primary flow carried the bubbles towards the outlet. In addition, it was found that the vortex stretching, compression expansion, and baroclinic torque terms primarily influence the vorticity transport equation in this context. This work may provide a reference value to the design of JPCRs for water treatment.

3.
Zhen Ci Yan Jiu ; 49(4): 376-383, 2024 Apr 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38649205

RESUMO

OBJECTIVES: To observe the effects of moxibustion on blood lipid metabolism, pathological morphology of thoracic aorta, and the expression of silent information regulator 1 (SIRT1) and forkhead box transcription factor O3a (FOXO3a) in ApoE-/- atherosclerosis (AS) mice, so as to explore the potential mechanism of moxibustion in preventing and treating AS. METHODS: Ten C57BL/6J mice were fed a normal diet as the control group, and 30 ApoE-/- mice were fed a high-fat diet to establish the AS model, which were randomly divided into the model group, simvastatin group, and moxibustion group, with 10 mice in each group. From the first day of modeling, mice in the moxibustion group received mild moxibustion treatment at "Shenque"(CV8), "Yinlingquan"(SP9), bilateral "Neiguan"(PC6) and "Xuehai"(SP10) for 30 min per time;the mice in the simvastatin group were given simvastatin orally (2.5 mg·kg-1·d-1), with both treatments given once daily, 5 times a week, with a total intervention period of 12 weeks. The body weight and general condition of the mice were observed and recorded during the intervention period. After the intervention, the contents of serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured using an automated biochemistry analyzer. Hematoxylin eosin (HE) staining was used to observe the pathological morphology of the thoracic aorta. ELISA was used to measure the contents of serum oxidized low-density lipoprotein (ox-LDL) and superoxide dismutase (SOD) activity. Western blot and real-time fluorescent quantitative PCR analysis were used to detect the expression levels of SIRT1 and FOXO3a protein and mRNA in the thoracic aorta. RESULTS: Compared with the control group, body weight at the 8th and 12th week, serum TC, TG, LDL-C, and ox-LDL contents of the model group mice were significantly increased(P<0.05, P<0.01), while the HDL-C contents, SOD activity, and the expression levels of SIRT1 protein and mRNA in the thoracic aorta were significantly decreased(P<0.05, P<0.01). HE staining showed thickening of the aortic intima, endothelial cell degeneration, swelling, and shedding. Compared with the model group, body weight at the 8th and 12th week, serum TC, TG, LDL-C, and ox-LDL contents of mice in the simvastatin group and moxibustion group were significantly decreased(P<0.01), while the serum SOD activity, expression levels of SIRT1 protein and mRNA in the thoracic aorta were significantly increased(P<0.01). The HDL-C contents were significantly increased in the simvastatin group(P<0.05). The thoracic aortic structure was more intact in both groups, with a more regular lumen and orderly arrangement of the elastic membrane in the media, and a slight amount of endothelial cell degeneration and swelling in the intima. There was no significant difference in the evaluated indexes between the moxibustion group and the simvastatin group and the pathological changes in the thoracic aorta were similar between the two groups. CONCLUSIONS: Moxibustion can reduce the body weight of AS model mice, regulate lipid levels, repair vascular intima, and alleviate endothelial damage. Its mechanism of action may be related to the regulation of the SIRT1/FOXO3a signaling pathway to improve oxidative damage.


Assuntos
Apolipoproteínas E , Aterosclerose , Proteína Forkhead Box O3 , Moxibustão , Sirtuína 1 , Animais , Humanos , Masculino , Camundongos , Pontos de Acupuntura , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/metabolismo , Aterosclerose/genética , Aterosclerose/terapia , Proteína Forkhead Box O3/metabolismo , Proteína Forkhead Box O3/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Sirtuína 1/metabolismo , Sirtuína 1/genética , Triglicerídeos/sangue , Triglicerídeos/metabolismo
4.
Org Lett ; 25(12): 2012-2017, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36944029

RESUMO

Employing N-fluorobenzenesulfonimide (NFSI) as a nitrogen-centered radical (NCR) precursor, an intermolecular C(sp2)-N coupling on heteroarenes or substituted benzenes with remote activated aniline derivatives via copper catalyzed N-N radical relay strategy at room temperature is developed. Good to excellent yields are acquired, and no ligand or additive is required. Reaction scope investigation and preliminary mechanistic studies demonstrate that the remote activating strategy and delicate control on the reactivities of active NCR species are essential to guarantee satisfactory chemo- and site-selectivity.

5.
Ultrason Sonochem ; 99: 106544, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37544171

RESUMO

Hydrodynamic cavitation (HC) is widely considered a promising process intensification technology. The novel advanced rotational hydrodynamic cavitation reactors (ARHCRs), with considerably higher performance compared with traditional devices, have gained increasing attention of academic and industrial communities. The cavitation generation unit (CGU), located on the rotor and/or stator of an ARHCR, is utilized to generate cavitation and consequently, its geometrical structure is vital for the performance. The present work studied, for the first time, the effect of the arrangement of CGU on the performance of a representative ARHCR by employing computational fluid dynamics based on the "simplified flow field" strategy. The effect of CGU arrangement, which was neglected in the past, was evaluated: radial offset distance (c), intersection angle (ω), number of rows (N), circumferential offset angle (γ), and radial spacing (r). The results indicate that the CGU, with an arrangement of a low ω and moderate c, N, γ, and r, performed the highest cavitation efficiency. The corresponding reasons were analyzed by combining the flow field and cavitation pattern. Moreover, the results also exposed a weakness of the "simplified flow field" strategy which may induce the unfavorable "sidewall effect" and cause false high-pressure region. The findings of this work may provide a reference value to the design of ARHCRs.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 271: 120856, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35042043

RESUMO

The taste of different flavor liquor is multifarious, but the same brand liquor with different quality is truth. The essence of supramolecular ethanol-water clusters and their intrinsic structural differences in three kinds of Fenjiu are studied by two-dimensional correlation spectra (2D-COS) of fluorescence and Raman. The 2D-COS of fluorescence reveals the prominent emission peaks of three Fenjiu are apparently different. The central fluorescence peak of Fenjiu (a) is located at 330 nm, corresponding to the cluster of (H2O)m(EtOH)n. In Fenjiu (b), the emission peak appears near 310 nm, while those of Fenjiu (c) appear mainly near 310 and 373 nm, corresponding to the clusters of (H2O)(EtOH)n and (H2O)m(EtOH), respectively. Based on 2D-COS of Raman, the peak of Fenjiu (b) at 3440 cm-1 changes initially, indicating its disorder degree is getting higher with continuous dilution with water. However, along with the dilution of Fenjiu (a) and Fenjiu (c), the peak located near 3200 cm-1 changes in priority, indicating that the degree of association between ethanol and water is high, and the clusters formed there are stable. Therefore, this work provides the combined methods to distinguish different supramolecular sets in Fenjiu, applying liquor differentiation in the future.


Assuntos
Etanol , Água , Bebidas Alcoólicas/análise , Etanol/química , Espectrometria de Fluorescência , Água/química
7.
Genes (Basel) ; 13(10)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36292654

RESUMO

Cancer prognosis analysis is of essential interest in clinical practice. In order to explore the prognostic power of computational histopathology and genomics, this paper constructs a multi-modality prognostic model for survival prediction. We collected 346 patients diagnosed with hepatocellular carcinoma (HCC) from The Cancer Genome Atlas (TCGA), each patient has 1-3 whole slide images (WSIs) and an mRNA expression file. WSIs were processed by a multi-instance deep learning model to obtain the patient-level survival risk scores; mRNA expression data were processed by weighted gene co-expression network analysis (WGCNA), and the top hub genes of each module were extracted as risk factors. Information from two modalities was integrated by Cox proportional hazard model to predict patient outcomes. The overall survival predictions of the multi-modality model (Concordance index (C-index): 0.746, 95% confidence interval (CI): ±0.077) outperformed these based on histopathology risk score or hub genes, respectively. Furthermore, in the prediction of 1-year and 3-year survival, the area under curve of the model achieved 0.816 and 0.810. In conclusion, this paper provides an effective workflow for multi-modality prognosis of HCC, the integration of histopathology and genomic information has the potential to assist clinical prognosis management.


Assuntos
Carcinoma Hepatocelular , Aprendizado Profundo , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Prognóstico , Genômica/métodos , RNA Mensageiro/genética
8.
Front Nutr ; 9: 910589, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757265

RESUMO

A fluid food conveying pump is used to convey edible or nutritional fluids and semi-fluids (containing suspended soft and hard particles and with different viscosities), such as water, glycerin, yogurt, and juice concentrate. Since different fluid food have different viscosities, the internal flow characteristics and conveying performance of food conveying pump are greatly affected by viscosity. To obtain the influence law of fluid food viscosity on the internal flow characteristics of the pump, the internal flow characteristics of food conveying pump when conveying food of 4 different viscosities (water, glycerin, 67.2 °Bx wild jujube juice, and 71.0 °Bx haw juice) were compared and observed in this study. The results showed that, with the increase in food viscosity, the overall flow loss in the pump, the entropy generation, and the proportion of total entropy generation in the pump chamber increase, but the conveying performance of the food conveying pump gets worse; however, the pressure pulsation intensity caused by static and dynamic interferences decreases with the increase in viscosity.

9.
Front Nutr ; 9: 884835, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634413

RESUMO

In the field of food processing, the processing of liquid foods has always played an important role. Liquid foods have high requirements for the processing environment and equipment. As the core equipment in liquid foods processing, food transport pumps are widely used in liquid foods production, processing and transportation. Most liquid foods are non-Newtonian and vulnerable to vibration, noise, and temperature rise produced by rotary motions of food transport pumps in operation, which can finally affect foods safety. Therefore, this review summarizes the impact of mechanical vibration, noise, and temperature rise on liquid food products, with the aim of ensuring food safety while designing a cleaner, safer and more reliable food transport pumps in the future.

10.
RSC Adv ; 11(31): 18966-18973, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35478631

RESUMO

Employing sulfonyl azide as a nitrogen donor, a visible-light-enabled aerobic dealkylative imidation of tertiary and secondary amines involving C(sp3)-C(sp3) bond cleavage with moderate to excellent yields at room temperature is described. It has been demonstrated that this imidation could take place spontaneously upon visible-light irradiation, and could be facilitated considerably by a ruthenium photocatalyst and oxygen. An alternative mechanism to the previous aerobic photoredox pathway has also been proposed.

11.
Ultrason Sonochem ; 70: 105311, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32871384

RESUMO

Hydrodynamic cavitation (HC) has emerged as one of the most potential technologies for industrial-scale water treatment. The advanced rotational hydrodynamic cavitation reactors (ARHCRs) that appeared recently have shown their high effectiveness and economical efficiency compared with conventional devices. For the interaction-type ARHCRs where cavitation is generated from the interaction between the cavitation generation units (CGUs) located on the rotor and the stator, their flow field, cavitation generation mechanism, and interaction process are still not well defined. The present study experimentally and numerically investigated the cavitation flow characteristics in a representative interaction-type ARHCR which has been proposed in the past. The cavitation generation mechanism and development process, which was categorized into "coinciding", "leaving", and "approaching" stages, were analyzed explicitly with experimental flow visualization and computational fluid dynamics (CFD) simulations. The changes in the cavitation pattern, area ratio, and sheet cavitation length showed high periodicity with a period of 0.5 ms/cycle at a rotational speed of 3,600 rpm in the flow visualization. The experimental and CFD results indicated that sheet cavitation can be generated on the downstream sides of both the moving and the static CGUs. The sheet cavitation was induced and continuously enlarged in the "leaving" and "approaching" stages and was crushed after the moving CGUs coincided with the static CGUs. In addition, vortex cavitation was formed in the vortex center of each CGU due to high-speed rotating fluid motion. The shape and size of the vortex cavitation were determined by the compression effect produced by the interaction. The findings of this work are important for the fundamental understanding, design, and application of the ARHCRs in water treatment.

12.
Front Chem ; 8: 600594, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33282843

RESUMO

Environmental pollution as a result of urban and industrial wastewater has become an increasingly prominent issue. Rivers, lakes, and oceans that have become eutrophicated or polluted by suspended solids and hazardous substances in wastewater have endangered the environment. A root cause of this is the discharge of untreated urban and industrial wastewater into the ecosystem. As a solution to the pollution, wastewater treatment facilities have seen increasingly rapid development. Sewage pumps are designed to transport urban and industrial wastewater containing solid particles or hazardous substances to water treatment centers for purification and treatment. Sewage pumps are of great importance in the entire wastewater treatment system. Sewage in the environment where sewage pumps work usually contains sands, suspended particles, and plenty of saline ions. Flow passage components and sealing elements of the pump become vulnerable to abrasion and chemical corrosion, which further challenges operational stability of the pump. Research has remained focused on how to improve reliability of sewage pumps under severe conditions. Because of advances in materials science, the application of an increasing number of new materials has been witnessed, such as carbon-based composite materials and carbon nanomaterials, thanks to their fine self-lubrication performance, heat resistance, thermal and electrical conductivity, chemical stability, heat and seismic resistance, as well as plasticity. These properties contribute to enormous potential that new carbon-based composite materials and carbon nanomaterials have to offer in terms of corrosion resistance. This paper outlines application scenarios, research progress, and the prospect of new materials in sewage pumps.

13.
ACS Appl Mater Interfaces ; 11(1): 269-277, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30525427

RESUMO

The porous microstructure of scaffolds is an essential consideration for tissue engineering, which plays an important role for cell adhesion, migration, and proliferation. It is crucial to choose optimum pore sizes of scaffolds for the treatment of various damaged tissues. Therefore, the proper porosity is the significant factor that should be considered when designing tissue scaffolds. Herein, we develop an improved emulsion template method to fabricate gelatin-based scaffolds with controllable pore structure. Gelatin droplets were first prepared by emulsification and then solidified by genipin to prepare gelatin microspheres. The microspheres were used as a template for the fabrication of porous scaffolds, which were gathered and tightened together by dialdehyde amylose. The results showed that emulsification can produce gelatin microspheres with narrow size distribution. The size of gelatin microspheres was easily controlled by adjusting the concentration of gelatin and the speed of mechanical agitation. The gelatin-based scaffolds presented macroporous and interconnected structure. It is interesting that the pore size of scaffolds was directly related to the size of gelatin microspheres, displaying the same trend of change in size. It indicated that the gelatin microspheres can be used as the proper template to fabricate gelatin-based scaffold with a desired pore structure. In addition, the gelatin-based scaffolds possessed good blood compatibility and cytocompatibility. Overall, the gelatin-based scaffolds exhibited great potential in tissue engineering.


Assuntos
Gelatina/química , Teste de Materiais , Microesferas , Alicerces Teciduais/química , Animais , Adesão Celular , Linhagem Celular , Humanos , Camundongos , Porosidade , Coelhos , Engenharia Tecidual
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