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1.
ACS Nano ; 17(11): 10976-10986, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37222703

RESUMO

Photocatalytic CO2 conversion to fuels is a promising strategy for achieving global carbon neutrality. However, infrared light, which accounts for ∼50% of the full sunlight spectrum, has not yet been effectively utilized via photocatalysis. Here, we present an approach to directly power photocatalytic CO2 reduction using near-infrared light. This near-infrared light-responsive process occurs on an in situ generated Co3O4/Cu2O photocatalyst with a nanobranch structure. Photoassisted Kelvin probe force microscopy and relative photocatalytic measurements demonstrate the increase of surface photovoltage after illumination by near-infrared light. We also find that Cu(I) on this in situ generated Co3O4/Cu2O could facilitate the formation of a *CHO intermediate, thus enabling a high-performance CH4 production with a yield of 6.5 µmol/h and a selectivity of 99%. Moreover, we perform a practically oriented direct solar-driven photocatalytic CO2 reduction under concentrated sunlight and achieve a fuel yield of 12.5 µmol/h.

2.
Ann Surg ; 277(3): e689-e698, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34225294

RESUMO

OBJECTIVE: To investigate postoperative functional connectivity (FC) alterations across impaired cognitive domains and their causal relationships with systemic inflammation. BACKGROUND: Postoperative cognitive dysfunction commonly occurs after cardiac surgery, and both systemic and neuroinflammation may trigger its development. Whether FC alterations underlying deficits in specific cognitive domains after cardiac surgery are affected by inflammation remains unclear. METHODS: Seventeen patients, who underwent cardiac valve replacement, completed a neuropsychological test battery and brain MRI scan before surgery and on days 7 and 30 after surgery compared to age-matched healthy controls. Blood samples were taken for tumor necrosis factor-a and interleukin-6 measurements. Seed-to-voxel FC of the left dorsolateral prefrontal cortex (DLPFC) was examined. Bivariate correlation and linear regression models were used to determine the relationships among cognitive function, FC alterations, and cytokines. RESULTS: Executive function was significantly impaired after cardiac surgery. At day 7 follow-up, the surgical patients, compared to the controls, demonstrated significantly decreased DLPFC FC with the superior parietal lobe and attenuated negative connectivity in the default mode network, including the angular gyrus and posterior cingulate cortex. The left DLPFC enhanced the connectivity in the right DLPFC and posterior cingulate cortex, all of which were related to the increased tumor necrosis factor-a and decreased executive function up to day 7 after cardiac surgery. CONCLUSIONS: The decreased FC of executive control network and its anticorrelation with the default mode network may contribute to executive function deficits after cardiac surgery. Systemic inflammation may trigger these transient FC changes and executive function impairments.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Função Executiva , Humanos , Encéfalo , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Inflamação/etiologia , Fatores de Necrose Tumoral , Imageamento por Ressonância Magnética
3.
Skin Res Technol ; 28(2): 254-264, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34751480

RESUMO

BACKGROUND: Humans can recognize the physical properties of objects by touching them, even when vision is unavailable. Tactile perception is important for humans in interacting with the environment. The triangular ridged textures are usually added to surface to improve the grip reliability of products, but the sharp edge of triangular ridge induces sharp and uncomfortable feeling. MATERIALS AND METHODS: To study the effect of the edge shape of triangular ridged texture on brain activity, functional magnetic resonance imaging technique was used to obtain the blood oxygen level-dependent (BOLD) signal of subjects during the touching of textured surfaces. Samples with sharp, round, and flat shape ridged textures were chosen as the tactile stimulus. RESULTS: The contralateral postcentral gyrus, the precentral gyrus, the inferior parietal lobule, and the supramarginal gyrus, corresponding with the functional regions of the primary somatosensory cortex (SI), the secondary somatosensory cortex (SII), and the primary motor cortex (MI) were related to the perception of three shape ridged textures. The main brain activation located in the postcentral gyrus and the SI. The tactile information of three shape ridged textures was received by Brodmann area (BA) 3 of the SI, and then inputted to BA 2 of the SI, the further tactile discrimination of shape of ridged textures was involved in BA40 of the SII. The intensity, the areas, and the percent signal change (PSC) of brain activation that were evoked by different shape ridged textures were related to the geometric structures of the ridged textures. The more complex the geometric structures of texture are, the larger the intensity, the area, and the PSC in brain activation are. The negative BOLD responses of the ipsilateral sensory cortex that were evoked by the flat ridged texture indicated the ipsilateral neuronal inhibition within the sensory systems. The bilateral precuneus, the superior parietal gyrus, and the inferior parietal gyrus, corresponding with the functional areas of the SII (BA40) and the SSA(BA7), were involved in the tactile discriminate of the differences in shapes of ridged textures. The differences in brain activation were related to the differences in geometric structures of the ridged texture. The larger the differences in geometric structure of texture are, the larger the differences in brain activation are. This study revealed the activated location of brain related to the tactile stimulation of different edge shape of ridged textures and the relationship between the geometric structures of ridged texture and brain activities. This research contributes to optimize surface tactile characteristics on products, especially effective surface textures design for good grip.


Assuntos
Percepção do Tato , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Dedos/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Estimulação Física/métodos , Reprodutibilidade dos Testes , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Percepção do Tato/fisiologia
4.
Front Neurosci ; 15: 676837, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248483

RESUMO

The triangular ridged surface can improve the grip reliability of products, but the sharp edge of triangular ridge induces sharp and uncomfortable feeling. To study the effect of edge shape (sharp, round, and flat shape) of triangular ridges on brain activity during touching, electroencephalograph (EEG) signals during tactile perception were evaluated using event-related potentials (ERP) and non-linear analysis methods. The results showed that the early component of P100 and P200, and the late component of P300 were successfully induced during perceiving the ridged texture. The edge shape features affect the electrical activity of brain during the tactile perceptions. The sharp shape feature evoked fast P100 latency and high P100 amplitude. The flat texture with complex (sharp and flat) shape feature evoked fast P200 latency, high P200 amplitude and RQA parameters. Both of the sharp shape and complex shape feature tended to evoke high peak amplitude of P300. The large-scale structures of recurrence plots (RPs) and recurrence quantification analysis (RQA) parameters can visually and quantitatively characterize the evolution regulation of the dynamic behavior of EEG system along with the tactile process. This study proved that RPs and RQA were protential methods for the feature extraction and state recognition of EEG during tactile perception of textured surface. This research contributes to optimize surface tactile characteristics on products, especially effective surface textures design for good grip.

5.
J Adv Res ; 21: 129-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32071781

RESUMO

The formation of tactile perception is related to skin receptors and the cerebral cortex. In order to systematically study the tactile perception from finger friction to the brain response, a 32-channel Brain Products system and two tri-axial force sensors were used to obtain electroencephalograph (EEG) and friction signals during fingers exploring grating surfaces. A finite element finger model was established to analyze the stress changes of the skin receptors during tactile perception. Samples with different grating widths and spaces were chosen. The results indicated that different gratings induced different stress concentrations within skin that stimulated Meissner and Merkel receptors. Skin friction was affected by gratings during the tactile perception. It was also found that P300 evoked by gratings was related with the skin deformation, contact area, friction force, and stress around cutaneous mechanoreceptors. The wider grating width generated larger skin deformation, friction force, and stress, which induced stronger tactile stimulation. The smaller grating spacing generated higher vibration frequency, inducing stronger tactile stimulation. The latency of the P300 peak was related to the difference between the textured target stimulus and the smooth non-target stimulus. This study proofed that there was a relationship between the activation in brain regions, surface friction, and contact conditions of skin during the tactile perception. It contributes to understanding the formation process and cognitive mechanism of tactile perception of different surface textures.

6.
J Environ Manage ; 239: 306-315, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913481

RESUMO

Soot is an important toxic pollutant generated during high-temperature incineration of solid waste (i.e., biomass and plastic waste) under air-lean conditions, and has a great impact on flame radiation. The main objective of this work is to study the synergistic effect of biomass and polyurethane co-pyrolysis on soot formation at high temperatures (1100-1250 °C). The effects of temperature, biomass species, and co-pyrolysis ratio on the yield, morphology, composition and reactivity of soot particles are studied. Results show that under controlled co-pyrolysis conditions, the measured soot yield from co-pyrolysis of biomass and polyurethane is lower than the theoretical value by weight average, while the particle size distribution tends to concentrate on a smaller diameter range. The degree of synergistic effect increases with the increasing biomass ratio (0-50 wt%) and decreasing pyrolysis temperature. Wood in co-pyrolysis presents a stronger synergistic effect on soot yields than straw co-pyrolysis does. Degree of synergistic effect on soot oxidation reactivity depends much on the biomass addition ratio but less on pyrolysis temperature. At 10 wt% straw addition ratio, co-pyrolysis exerts a negative synergistic effect on soot oxidation reactivity, while the synergistic effect turns significantly positive when the straw addition ratio increases to 50 wt%.


Assuntos
Biomassa , Poliuretanos/química , Fuligem/química , Temperatura Alta , Pirólise , Madeira
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