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1.
Small ; : e2310028, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651514

RESUMO

In this study, two novel donor-acceptor (D-A) copolymers are designed and synthesized, DTBT-2T and DTBT-2T2F with 2,2'-bithiophene or 3,3'-difluoro-2,2'-bithiophene as the donor unit and dithienobenzothiadiazole as the acceptor unit, and used them as donor materials in non-fullerene organic solar cells (OSCs). Due to enhanced planarity of polymer chains resulted by the intramolecular F···S noncovalent interactions, the incorporation of 3,3'-difluoro-2,2'-bithiophene unit instead of 2,2'-bithiophene into the polymers can enhance their molecular packing, crystallinity and hole mobility. The DTBT-2T:L8-BO based binary OSCs deliver a power conversion efficiency (PCE) of only 9.71% with a Voc of 0.78 V, a Jsc of 20.69 mA cm-2 , and an FF of 59.67%. Moreover, the introduction of fluoro atoms can lower the highest occupied molecular orbital levels. As a result, DTBT-2T2F:L8-BO based single-junction binary OSCs exhibited less recombination loss, more balanced charge mobility, and more favorable morphology, resulting in an impressive PCE of 17.03% with a higher Voc of 0.89 V, a Jsc of 25.40 mA cm-2, and an FF of 75.74%. These results indicate that 3,3'-difluoro-2,2'-bithiophene unit can be used as an effective building block to synthesize high performance polymer donor materials. This work greatly expands the selection range of donor units for constructing high-performance polymers.

2.
Vascular ; : 17085381241254426, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753492

RESUMO

OBJECTIVE: To investigate the safety and efficacy of endovascular treatment for totally occlusive lesions of the subclavian artery (SCA). METHODS: A retrospective study was performed on 57 patients treated with angioplasty and stenting, including 42 males and 15 females, with an average age of 61.8 years (range: 49 to 81 years). Efficacy, safety, and complications were evaluated. RESULTS: Procedural success was achieved for 47/57 patients and symptoms were relieved. Rat-tail occlusion is the most common type, and all cases were successfully recanalized. Plain type occlusion is less common with a recanalization rate of 55.6%. Hilly and plain occlusions are the main types of stent implantation failure. Through univariate analysis and trend matching analysis, the type of SCA occlusion and surgical approach had statistical significance on the success rate of surgery. The mean follow-up time was 34.6 ± 16.2 months. The cumulative stent patency rates at 1, 3, and 5 years were 95.5%, 86.4%, and 77.3% in the calcified plaque group and 92.0%, 76.0%, and 68.0% in the non-calcified plaque group, respectively. The 3-year and 5-year patency rates in the calcified plaque group were higher than those in the non-calcified plaque group (p < .05). CONCLUSION: Different occlusion types and surgical approaches can affect the surgical success rate. The combined femoral and brachial approach can improve the rate of recanalization of SCA occlusions. The patency rates at 3 and 5 years in the calcified plaque group were higher than those in the non-calcified plaque group.

3.
BMC Microbiol ; 23(1): 39, 2023 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-36765272

RESUMO

Probiotics are defined as live microbial food elements that are beneficial to human health. Lacticaseibacillus casei T1 was considered to have potential as a bioactive ingredient in functional foods, which was isolated from kurut. Previous research by our group proved that L. casei T1 could prevent inflammatory responses caused by Helicobacter pylori. This study aimed to investigate whether treatment with L. casei T1 resulted in a suppressive effect on H. pylori-induced oxidative stress and inflammatory responses. The results showed that treatment with L. casei T1 could relieve H. pylori-induced overexpression of inflammatory cytokines in GES-1 cells. Experiments in animals suggested that taking long-term L. casei T1 could reduce oxidative stress and inflammatory cytokines and improve H. pylori-induced gastric mucosal damage. Furthermore, taking L. casei T1 could increase the relative abundance of beneficial intestinal bacterium (Lachnospiraceae and Odoribacter) of H. pylori-infected mice and help in maintaining the balance of intestinal microflora.Collectively, L. casei T1 had certain degrees of therapeutic effect against H. pylori. In the future, it combined with antibiotics for H. pylori eradication deserves further study.


Assuntos
Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Lacticaseibacillus casei , Probióticos , Camundongos , Humanos , Animais , Lacticaseibacillus , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/prevenção & controle , Infecções por Helicobacter/microbiologia , Citocinas , Probióticos/farmacologia , Probióticos/uso terapêutico , Inflamação
4.
Pak J Pharm Sci ; 34(2): 493-498, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34275821

RESUMO

P. petiolosa as a typical Chinese herbal medicine has been generally utilized as Chinese native medicine formulation for treatment of chronic bronchitis, bronchial asthma and pneumoconiosis. The objective of this study was to evaluate the anti-inflammatory and antibacterial activities of P. petiolosa ethyl acetate extract (PPEAE) against S. aureusin mice. In our study, mice were infected pneumonia by S. aureus, colonization of S. aureus in lung tissue was calculated and the number of white blood cells (WBC) in blood was measured. Meanwhile, the hematoxylin-eosin staining (H&E) was observed and the Real-time PCR was employed to determine the relative mRNA expression. The results showed that, after treated with PPEAE the wet/dry (W/D) weight ratio and the number of WBC decreased dramatically, the number of S. aureus was significantly reduced. Furthermore, H&E staining showed that PPEAE obviously relieved the inflammation of infected mice and real-time PCR results indicated that PPEAE significantly down regulated the inflammatory iNOS, TNF-α and up regulated the anti-inflammatory HO-1 mRNA. In summary, our study revealed that application of crude product PPEAE had prominent antibacterial activity against S. aureus. PPEAE significantly reduced the biomass of S. aureus and effectively relieved the inflammation of S. aureus-induced pneumonia.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Pulmão/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pneumonia Estafilocócica/genética , Polypodiaceae , Staphylococcus aureus/efeitos dos fármacos , Animais , Heme Oxigenase-1/efeitos dos fármacos , Heme Oxigenase-1/genética , Inflamação/genética , Inflamação/metabolismo , Pulmão/metabolismo , Pulmão/microbiologia , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/genética , Camundongos , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/genética , Pneumonia Estafilocócica/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética
5.
Biochem Biophys Res Commun ; 524(1): 36-42, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-31980170

RESUMO

Gastric epithelial cells (GES-1) stimulated by Helicobacter pylori (H. pylori) would affect the expression of related genes and induce the immune response of the cells. Abnormal methylation of DNA was one of the main causes. The aim of this study was to investigate phosphoinositol-3-kinase adaptor protein 1(PIK3AP1), which was screened from the chip data as an immune gene candidate to against the inflammatory response of cells caused by H. pylori infection. PIK3AP1 plays a key role in PI3K/AKT signaling pathway. The gene chip analysis and experimental results confirmed that PIK3AP1 expression was downregulated and PIK3AP1 promoter was hypermethylated after H. pylori stimulation in GES-1 cells. Meanwhile, the expression level of PIK3AP1 was significantly upregulated after 5-aza-dc treatment, and its expression was higher after 5-aza-dc and H. pylori co-treatment than that of H. pylori treatment but lower than that of 5-aza-dc treatment. Therefore, hypermethylation was the main reason for the down-regulation of PIK3AP1 after H. pylori stimulation. In addition, the intervention of PIK3AP1 inhibited the expression of downstream gene AKT, and suppressing the expression of the immunoinflammatory gene IL-6 in GES-1 cells. Furthermore, the intervention of PIK3AP1 would promote cell proliferation. In summary, hypermethylation of the PIK3AP1 promoter was accompanied by reduction of the expression level of PIK3AP1 in GES-1 cells by H. pylori stimulation. The expression of PIK3AP1, AKT, and IL-6 genes was positively correlated, Meanwhile, the PIK3AP1 can affect the proliferation of GES-1 cells. These results would be helpful to understand the innate immune response function of PIK3AP1 to pathogenic bacterial infection in the stomach.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Decitabina/química , Células Epiteliais/metabolismo , Mucosa Gástrica/citologia , Infecções por Helicobacter/metabolismo , Helicobacter pylori/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proliferação de Células , Metilação de DNA , Decitabina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
6.
Mol Cell Biochem ; 465(1-2): 1-11, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31792649

RESUMO

Long noncoding ribonucleic acids (lncRNAs) are critical regulators in various biological processes. In the present study, we aimed to explore whether miR140-3p was involved in the underlying molecular mechanisms of small nucleolar RNA host gene 1 (SNHG1) in myocardial ischemia/reperfusion (I/R) injury. A mouse model of I/R injury and hypoxia-reoxygenation (H/R)-stimulated human umbilical vein endothelial cells (HUVECs) was used in this study. Cell proliferation was detected by MTT. The mRNA and protein levels of vascular endothelial growth factor (VEGF), VE-cadherin, and MMP2 were detected by RT-PCR and western blot, respectively. The angiogenesis was assessed by tube formation assay. Cell migration was assessed using wound-healing assay. Results showed that SNHG1 expression was increased in the cardiac microvasculature of a mouse model of I/R injury and in H/R-stimulated HUVECs. H/R stimulation significantly reduced cell proliferation, tube formation, and cell migration, but increased expression of VEGF, VE-cadherin, and MMP2. SNHG1 upregulation under H/R increased HUVECs proliferation, tube formation, and cell migration, and upregulated expression of VEGF, VE-cadherin, and MMP2, compared with the H/R group. SNHG1 knockdown exhibited the opposite effect. SNHG1 functioned as a competing endogenous RNA (ceRNA) of miR-140-3p. HIF-1α was identified as a target of miR-140-3p. SNHG1 upregulation enhanced cell proliferation, tube formation, and expression of VEGF, VE-cadherin, and MMP2 through HIF-1α/VEGF signaling. This process could be offset by miR-140-3p mimic or VEGF inhibitor. Our results reveal a novel protective function of SNHG1 that furthers understanding of cardiac I/R injury and provides experimental evidence for future therapy.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Camundongos , Traumatismo por Reperfusão Miocárdica/patologia , Neovascularização Fisiológica
7.
Angew Chem Int Ed Engl ; 59(2): 752-757, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31644834

RESUMO

The first example of a two-state (neutral and reduced), stable electron-accepting material and its radical anion is presented. FV-PDI, generated from cyclocarbonylation and then a carbonyl coupling reaction, shows a largely degenerate LUMO of -4.38 eV based on the delocalization of π-electrons across the whole molecular skeleton through a fulvalene bridge. The stability and electron affinity allow spontaneous electron transfer to afford a stable radical anion. Spectroscopic characterization and structural elucidation showed that the radical anion [FV-PDI].- has remarkable stability and near-infrared absorptions extending to 1200 nm. Single-crystal X-ray diffraction analyses revealed significant changes in the molecular shape and packing arrangement of the formed radical anion. The central C-C bond linking the two PDI halves is lengthened from approximately 1.33 to 1.43 Å, and the alternating arrangement of positively and negatively charged units favor the stable charge-transfer complex.

8.
Pak J Pharm Sci ; 33(5): 2047-2052, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33824112

RESUMO

P. petiolosa as a typical Chinese herbal medicine has been generally utilized as Chinese native medicine formulation for treatment of chronic bronchitis, bronchial asthma and pneumoconiosis. The objective of this study was to evaluate the anti-inflammatory and antibacterial activities of P. petiolosa ethyl acetate extract (PPEAE) against S. aureus in mice. The air-dried leaves were extracted with ethyl acetate, mice were infected pneumonia by S. aureus. Colonization of S. aureus in lung tissue was calculated by plate colony count. The number of white blood cells (WBC) in blood was measured by blood cell automatic analyzer. The histopathological analysis of hematoxylin-eosin staining (H&E) of lung tissue was observed under microscope. Real-time PCR assay was employed to determine the relative mRNA expression of HO-1, iNOS and TNF-α. The results showed that, compared with control, after treated with PPEAE the wet/dry (W/D) weight ratio of mice lung tissue (decreased from 5.371 to 4.9) and the number of white blood cells (WBC) (decreased by 3.13×109/mL) decreased dramatically. The number of S. aureus was significantly reduced (from 1.93×105 CFU/mL to 26×103 CFU/mL) in lung tissue after treated with PPEAE. Furthermore, H&E staining showed that PPEAE obviously relieved the inflammation of lung tissue of infected mice. Meanwhile, real-time PCR results indicated that PPEAE down regulated the expression of inflammatory iNOS, TNF-α mRNA and up regulated the expression of anti-inflammatory HO-1 mRNA. In summary, this study revealed that application of crude product PPEAE had prominent antibacterial activity against S. aureus. PPEAE significantly reduced the biomass of S. aureus in lung tissue and effectively relieved the inflammation of S. aureus-induced pneumonia.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Pulmão/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pneumonia Estafilocócica/tratamento farmacológico , Polypodiaceae , Staphylococcus aureus/efeitos dos fármacos , Acetatos/química , Animais , Antibacterianos/isolamento & purificação , Anti-Inflamatórios/isolamento & purificação , Carga Bacteriana , Modelos Animais de Doenças , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Mediadores da Inflamação/metabolismo , Pulmão/metabolismo , Pulmão/microbiologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Pneumonia Estafilocócica/metabolismo , Pneumonia Estafilocócica/microbiologia , Polypodiaceae/química , Solventes/química , Staphylococcus aureus/crescimento & desenvolvimento , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Angew Chem Int Ed Engl ; 56(10): 2694-2698, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28128532

RESUMO

A star-shaped electron acceptor based on porphyrin as a core and perylene bisimide as end groups was constructed for application in non-fullerene organic solar cells. The new conjugated molecule exhibits aligned energy levels, good electron mobility, and complementary absorption with a donor polymer. These advantages facilitate a high power conversion efficiency of 7.4 % in non-fullerene solar cells, which represents the highest photovoltaic performance based on porphyrin derivatives as the acceptor.

10.
Int J Biol Macromol ; 236: 123879, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36870660

RESUMO

In the present study, a cascade dual catalytic system was used for the co-pyrolysis of lignin with spent bleaching clay (SBC) to efficiently produce mono-aromatic hydrocarbon (MAHs). The cascade dual catalytic system is composed of calcined SBC (CSBC) and HZSM-5. In this system, SBC not only acts as a hydrogen donor and catalyst in the co-pyrolysis process, but is also used as a primary catalyst in the cascade dual catalytic system after recycling the pyrolysis residues. The effects of different influencing factors (i.e., temperature, CSBC-to-HZSM-5 ratio, and raw materials-to-catalyst ratio) on the system were explored. It was observed that, when the temperature was 550 °C, the CSBC-to-HZSM-5 ratio was 1:1, and when the raw materials-to-catalyst ratio was 1:2, the highest bio-oil yield was 21.35 wt%. The relative MAHs content in bio-oil was 73.34 %, whereas the relative polycyclic aromatic hydrocarbons (PAHs) content was 23.01 %. Meanwhile, the introduction of CSBC inhibited the generation of graphite-like coke as indicated by HZSM-5. This study realizes the full resource utilization of spent bleaching clay and reveals the environmental hazards caused by spent bleaching clay and lignin waste.


Assuntos
Hidrocarbonetos Aromáticos , Lignina , Lignina/química , Argila , Pirólise , Temperatura Alta , Polifenóis/química , Ácido Hipocloroso , Hidrocarbonetos Aromáticos/química , Catálise , Biocombustíveis
11.
Environ Sci Pollut Res Int ; 30(2): 4853-4865, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35974282

RESUMO

Recycling organic waste and converting them into renewable energy are a promising route for environment protection and effective biochemical reactions suitable for industrial hydrogen synthesis. This study targeted to isolate a pure anaerobic culture with potential to hydrolyze different biomass and production of biohydrogen. For this, a sample of full-scale anaerobic digester, fed with a multicomponent solid, was inoculated on Reinforced Clostridial Medium (RCM) in strict anaerobic conditions. An anaerobic Clostridium butyricum CBT-1 strain was isolated, identified from morphological and 16S rRNA sequence. The CBT-1 culture expressed amylase, cellulase and peroxidases activities. The strain exhibited visual decolorization of both Azure B and crystal violet dyes. In batch fermentation experiment, the CBT-1 produced highest of 3.06, 2.67 and 2.46 mol/mol H2 yield from glucose, starch and cellulose respectively, whereas, the CBT-1 showed low 0.43 mol H2/mol of substrate from untreated rice straw due to lignin in compact structure and comparatively high H2 yield of 1.91 and 2.01 mol H2/mol of substrate rice straw hydrolysate and kitchen food waste (KFWS) respectively. The cumulative volumetric yield of H2 was 358.15, 300.8 and 294.5NmL/gSub from glucose, starch and cellulose respectively. Similarly, the cumulative H2 volume was 76.7, 184.4, 237.2 NmL/gVS from untreated rice straw, rice straw hydrolysate and kitchen food waste. This study emphasizes the prospects to find similar robust anaerobic culture for hydrolyzing complex biomass. Such strains could be used as standard co-inoculum for biohydrogen obtaining and as the biocatalyst for commercial scale applications.


Assuntos
Clostridium butyricum , Eliminação de Resíduos , Clostridium butyricum/genética , Clostridium butyricum/metabolismo , Anaerobiose , Alimentos , RNA Ribossômico 16S/genética , Reatores Biológicos , Fermentação , Celulose , Amido , Hidrogênio
12.
Foods ; 12(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37372591

RESUMO

This study was conducted to increase the enzymatic activity of Bacillus licheniformis XS-4, which was isolated from the traditional fermented mash of Xianshi soy sauce. The mutation was induced by atmospheric and room-temperature plasma (ARTP), and a mutant strain, mut80, was obtained. mut80 exhibited significant increases in protease and amylase activity by 90.54% and 143.10%, respectively, and the enhanced enzymatic activities were stably maintained after 20 consecutive incubations. Re-sequencing analysis of mut80 revealed that the mutation sites were located in 1518447(AT-T) and 4253106(G-A) in its genome, which was involved in the metabolic pathways of amino acids. The expression of the protease synthetic gene (aprX) increased 1.54 times, while that of the amylase gene (amyA) increased 11.26 times, as confirmed via RT-qPCR. Using ARTP mutagenesis, the present study proposes a highly efficient microbial resource with enhanced protease and amylase activity provided by B. licheniformis, which can potentially be used to improve the efficiency of traditional soy sauce fermentation.

13.
ACS Appl Mater Interfaces ; 15(3): 4275-4283, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36645327

RESUMO

Solving the contradiction between good solubility and dense packing is a challenge in designing high-performance nonfullerene acceptors. Herein, two simple nonfused ring electron acceptors (o-AT-2Cl and m-AT-2Cl) carrying ortho- or meta-substituted hexyloxy side chains can be facilely synthesized in only three steps. The two ortho-substituted phenyl side chains in o-AT-2Cl cannot freely rotate due to a big steric hindrance, which endows the acceptor with good solubility. Moreover, o-AT-2Cl displays a more ordered packing than m-AT-2Cl as revealed by the absorption measurement. When blended with polymer donor D18 for the fabrication of organic solar cells (OSCs), o-AT-2Cl-based devices exhibit a favorable morphology, more efficient exciton dissociation, and better charge transport. Consequently, the optimal OSCs based on D18:o-AT-2Cl exhibit a power conversion efficiency (PCE) of 12.8%, which is significantly higher than the moderate PCE (7.66%) for D18:m-AT-2Cl-based devices. Remarkably, o-AT-2Cl shows a higher figure-of-merit value compared with classic high-efficiency fused ring electron acceptors. As a result, our research succeeds in obtaining nonfused ring acceptors with cost-effective photovoltaic performance and provides a valuable experience for simultaneously improving solubility as well as ensuring ordered packing of acceptors through regulating the steric hindrance via changing the position of substituents.

14.
Environ Sci Pollut Res Int ; 30(24): 64904-64931, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37097560

RESUMO

The main intention in the modern era is to make life and activities on earth more comfortable by adding necessary products through biological machinery. Millions of tons of biological raw materials and lignocellulosic biomass are wasted by burning each year without providing benefits to living organisms. Instead of being the cause of disturbing the natural environment by increasing global warming and pollutants worldwide, now, it is the need of the hour to develop an advanced strategy to utilize these biological raw materials to produce renewable energy resources to meet the energy crisis. The review presents the idea of multiple enzymes in one step to hydrolyze complex biomaterials into useful products. The paper discusses how multiple enzymes are arranged in a cascade for complete hydrolysis of raw material in one-pot to prevent multistep, time consuming, and expensive methods. Furthermore, there was the immobilization of multiple enzymes in a cascade system with in vitro and in vivo conditions for reusability of enzymes. The role of genetic engineering, metabolic engineering, and random mutation techniques is described for the development of multiple enzyme cascades. Techniques that are involved in the improvement of native strain to recombinant strain for the enhancement of hydrolytic capacity were used. The preparative steps, before enzymatic hydrolysis like acid, and base treatment methods are more effective for improving the hydrolysis of biomass by multiple enzymes in a one-pot system. Finally, the applications of one-pot multienzyme complexes in biofuel production from lignocellulosic biomass, biosensor production, medicine, food industry, and the conversion of biopolymers into useful products are described.


Assuntos
Engenharia Genética , Lignina , Lignina/metabolismo , Biocombustíveis , Biomassa , Hidrólise
15.
Micromachines (Basel) ; 13(6)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35744564

RESUMO

The ankle is a crucial joint that supports the human body weight. An ankle sprain will adversely affect the patient's daily life, so it is of great significance to ensure its strength. To help patients with ankle dysfunction to carry out effective rehabilitation training, the bone structure and motion mechanism of the ankle were analyzed in this paper. Referring to the configuration of the lower-mobility parallel mechanism, a 3-RRS (R and S denote revolute and spherical joint respectively) parallel ankle rehabilitation robot (PARR) was proposed. The robot can realize both single and compound ankle rehabilitation training. The structure of the robot was introduced, and the kinematics model was established. The freedom of movement of the robot was analyzed using the screw theory, and the robot kinematics were analyzed using spherical analytics theory. A circular composite rehabilitation trajectory was planned, and the accuracy of the kinematics model was verified by virtual prototype simulation. The Multibody simulation results show that the trajectory of the target point is basically the same as the expected trajectory. The maximum trajectory error is about 2.5 mm in the simulation process, which is within the controllable range. The experimental results of the virtual prototype simulation show that the maximum angular deflection error of the three motors is 2° when running a circular trajectory, which meets the experimental requirements. Finally, a control strategy for passive rehabilitation training was designed, and the effectiveness of this control strategy was verified by a prototype experiment.

16.
J Phys Chem Lett ; 13(25): 5860-5866, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35727229

RESUMO

Most high-performance non-fullerene acceptors are of the acceptor-donor-acceptor (A-D-A)-type structure. Under photoexcitation, the intramolecular charge transfer effect on the A-D-A framework results in a large dipole moment change, facilitating the efficient generation of charge carriers. Achieving more efficient intramolecular charge transfer by adjusting the molecular structure is one of the current research ideas. Recently, we found that the power conversion efficiency can be improved from 4.41 to 13.13% by tuning the planarity of the non-fused ring electron acceptor backbone through steric hindrance of lateral substituents. We found that the planar backbone can effectively improve the intramolecular charge transfer, which has a great influence on the power conversion efficiency of the device. Our results demonstrate that charge transfer dynamics can be controlled by optimizing steric hindrance, which plays a crucial role in the photovoltaic performance of organic solar cells.

17.
Micromachines (Basel) ; 13(2)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35208377

RESUMO

This paper studies the stiffness of the parallel cable-driven upper limb rehabilitation robot (PCUR). Firstly, it was derived that the static stiffness expression of the PCUR was composed of platform pose stiffness KT and cable pose stiffness KS. It indicated that the static stiffness of the PCUR was related to the cable tension, the arrangement of the cable, and the cable stiffness. Secondly, a simulation model in MATLAB/Simscape Multibody was built. Cable tension was applied to make the moving platform in a static equilibrium state. The stiffness of the PCUR and the external force on the moving platform were changed, and the motion characteristics of the moving platform were obtained. Finally, the position changes of the moving platform under different external forces were analyzed, and the motion laws of the moving platform under different stiffnesses were summarized.

18.
RSC Adv ; 12(37): 24014-24025, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36093231

RESUMO

Fe-based oxygen carriers (OCs) are widely used in chemical looping steam reforming (CLSR) due to excellent resistance to carbon buildup, low toxicity, and high activity. In this study, a type of nano NiO-Fe2O3/Al2O3 Fe-based OC that can easily be reduced by fuels and re-oxidized by air was developed for use in glycerol CLSR. It was synthesized by co-precipitation and impregnation. Based on the quadratic regression orthogonal model, a quadratic polynomial function was established to investigate the effects of temperature (T), water/carbon ratio (S/C), and loading (M) on hydrogen content (HL) and hydrogen selectivity (S). The OCs were characterized by XRD, XPS, SEM/EDX-mapping, TEM, and H2-TPR to determine their physicochemical properties. XPS shows the Fe phase highly interacted with the Al2O3 supporting matrix by forming Fe aluminates in NiO-Fe2O3/Al2O3. The S (85.33%) and HL (78.41%) were obtained under the optimal conditions T = 600 °C, S/C = 1.0 mol mol-1 and M = 0. A hydrogen content fluctuation within 4% was obtained under T = 700 °C, S/C = 1.0 mol mol-1, and M = 2.5%, which means the cycle stability is perfect because of the addition of Ni. This study provides a basis for the development of efficient oxygen carriers in the CLSR system.

19.
ACS Appl Mater Interfaces ; 14(25): 28807-28815, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35696637

RESUMO

Two nonfused ring electron acceptors (NFREAs), BTh-OC8-2F and DTh-OC8-2F, with different molecular shapes are designed and synthesized. Both acceptors can form planar molecular shapes by the assistance of S···O intramolecular interactions. Differently, BTh-OC8-2F, with a linear molecular backbone and two trans-arranged side chains at the core unit, exhibits much stronger crystallinity than DTh-OC8-2, with a C-shape molecular shape and two cis-arranged steric side chains at the core unit. Thus, the DTh-OC8-2F based blend film displays a better nanoscale phase separation, more suppressed charge recombination, more efficient exciton dissociation, and lower nonradiative energy loss. Organic solar cells based on DTh-OC8-2F can deliver a power conversion efficiency of 14.13%, which is much higher than BTh-OC8-2F based ones (11.95%) and is also one of the highest values reported for organic solar cells based on NFREAs.

20.
ACS Appl Mater Interfaces ; 14(18): 21287-21294, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35484865

RESUMO

Three nonfused ring electron acceptors, Hexyl-0F, Isopropyl-0F, and Isopropyl-2F, are designed and synthesized. Unlike Hexyl-0F, Isopropyl-0F with two sterically hindered 2,4,6-triisopropyl-phenyl groups is highly soluble, which provides a good opportunity for solution processability. Compared with Isopropyl-0F, Isopropyl-2F with fluorinated end-groups exhibits red-shifted absorption. Due to these synergistic adjustment, Isopropyl-2F-based devices displayed a high power conversion efficiency of 12.55%, higher than that of Isopropyl-0F (9.49%). The result demonstrates that the introduction of large steric substituents in the π-bridge units and electron-withdrawing end-groups plays a positive role in the construction of high-efficiency nonfused ring electron acceptors.

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