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1.
Langmuir ; 39(43): 15401-15408, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37857566

RESUMO

Despite intensive investigations on the droplet receding contact angle on superhydrophobic surfaces, i.e., a key parameter characterizing surface wettability and adhesion, the quantitative correlation between the surface structure mechanical properties (softness) and the droplet receding contact angles remains vague. By systematically varying the geometric dimensions and mechanical properties of soft pillar arrays, we find that the droplet receding contact angles decrease with the decrease in the pillar spring constant. Most surprisingly, the densely packed pillar arrays may result in larger receding contact angles than those on sparsely packed pillars, opposing the understanding of rigid pillar arrays, where the receding contact angles increase with a decrease in the packing density of pillars. This is attributed to the collective effects of capillarity and elasticity, where the energy consumed by the sliding contact line, the energy stored in the distorted liquid-vapor interface, and the energy stored in the deflected pillar contribute to the droplet depinning characteristics. We develop an analytical model to predict the droplet receding contact angles on soft superhydrophobic pillar arrays with knowledge of the material intrinsic receding contact angle, the pillar geometry, and the pillar mechanical properties. The predictions are corroborated by the experimental data measured in this and prior studies.

2.
J Comput Assist Tomogr ; 47(4): 671-676, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37365699

RESUMO

OBJECTIVE: To investigate whether truncal-type occlusion based on multiphase computed tomographic angiography (mpCTA) was more effective for predicting intracranial atherosclerotic stenosis-related occlusion (ICAS-O) than occlusion type based on single-phase computed tomographic angiography (spCTA) in patients with acute ischemic stroke with large-vessel occlusion (AIS-LVO) in the middle cerebral artery (MCA). METHODS: Data were retrospectively collected from 72 patients with AIS-LVO in the MCA between January 2018 and December 2019. The occlusion types included truncal-type and branching-site occlusions. The association between ICAS-O and occlusion type based on the 2 computed tomographic angiography patterns was analyzed, and receiver operating characteristic curves were plotted for assessment. The areas under the curve were compared to determine the difference between the predictive powers of truncal-type occlusion based on mpCTA and spCTA. RESULTS: Among the 72 patients, 16 were classified as having ICAS-O and 56 as having embolisms. In univariate analysis, truncal-type occlusion was significantly associated with ICAS-O ( P < 0.001 for mpCTA and P = 0.001 for spCTA). After multivariable analysis, truncal-type occlusion based on both mpCTA and spCTA remained independently associated with ICAS-O ( P = 0.002 for mpCTA and P = 0.029 for spCTA). The areas under the curve were 0.821 for mpCTA and 0.683 for spCTA; this difference was statistically significant ( P = 0.024). CONCLUSIONS: In patients with AIS-LVO in the MCA, truncal-type occlusion based on mpCTA enables more accurate detection of ICAS-O than that based on spCTA.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Estudos Retrospectivos , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/complicações , Angiografia Cerebral/métodos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem
3.
Sensors (Basel) ; 22(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36236755

RESUMO

The multi-path ultrasonic flowmeter is widely used in engineering practice, and the flow algorithm is important for its accuracy. The least-squares estimation method is simple and efficient and has good engineering application value. In practical applications, noises are inevitably introduced to the measurement process because of the flowmeter itself or flow-field interference. The results of classical least squares will deviate from reality because it lacks robustness. In this regard, two flow algorithms of multi-path ultrasonic flowmeter are proposed based on least-squares and random-sampling consensus algorithms, which are widely used in the image field. The two algorithms can resist gross errors effectively by avoiding the interference of external points in the sampling points. To verify the effectiveness of the proposed algorithms, we take the double-bend flow field, which is a typical damaged flow field in engineering, as the research object, and then we compare the four algorithms. It can be seen that the two flow algorithms have higher accuracy and better robustness in the presence of interference noise.

4.
Clin Neurol Neurosurg ; 220: 107365, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35868203

RESUMO

OBJECTIVE: This is a single-center retrospective analysis of the clinical data of 516 patients with acute ischemic stroke who underwent intravenous thrombolysis. This study was conducted to compare the therapeutic efficacy of smokers and non-smokers. METHODS: Univariate analysis was used to analyze and compare the clinical data of smokers and non-smokers. Multivariate analysis was used to assess risk factors affecting the 90-day modified Rankin Scale (mRS) score. RESULTS: Among the 516 patients, 235 (45.5 %) were smokers. Univariate analysis showed that smokers have a better 90-day prognosis and a lower 90-day mRS score than non-smokers. Multivariate logistic regression analysis showed that smoking is not a protective factor affecting prognosis, while baseline National Institutes of Health Stroke Scale (NIHSS) score was an independent risk factor affecting the 90-day functional outcome. Subgroup analysis did not determine a relationship between the 90-day mRS score and the smoking intensity and duration. CONCLUSION: Smoking was not associated with a good 90-day prognosis after intravenous thrombolysis (IVT) treatment. The good clinical outcome of smokers in univariate analysis was bound up with their baseline characteristics. Baseline NIHSS score was the independent risk factor that affected the 90-day outcome of AIS patients undergoing IVT.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Humanos , AVC Isquêmico/tratamento farmacológico , Prognóstico , Estudos Retrospectivos , Fumar/efeitos adversos , Fumar/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
5.
Folia Neuropathol ; 58(1): 30-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32337955

RESUMO

This investigation evaluated the neuroprotective effect of melodinhenine B in a cerebral ischemia/reperfusion (I/R)-induced neuronal injury rat model. The effect of melodinhenine B was determined by evaluating the neurological deficit score, cerebral infarcted area, and blood-brain barrier (BBB) permeability. Moreover, the level of inflammatory cytokines and expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κß), interleukin-1ß (IL-1ß), NLRP3, zonula occludens-1 (ZO-1), and occluding proteins were estimated by Western blotting. Histopathological changes and immunohistochemical analysis were performed to estimate the effect of melodinhenine B on neuronal injury. The neurological deficit score, percentage of infarcted area, and BBB permeability were improved in the melodinhenine B-treated group of rats. Treatment with melodinhenine B attenuated the altered expression of NF-κß, IL-1ß, NLRP3, ZO-1, and occluding proteins in the brain tissue of I/R-induced neuronal injury rats. The inflammatory cytokine levels were reduced in the melodinhenine B-treated group. Histopathologically, melodinhenine B reversed the pathological changes in the brain tissues of I/R-induced neuronal injury rats. In conclusion, melodinhenine B protects against neuronal injury in cerebral ischemia-reperfusion injury rats by regulating the inflammasomes.


Assuntos
Isquemia Encefálica/patologia , Encéfalo/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/biossíntese , Traumatismo por Reperfusão/patologia , Animais , Anti-Inflamatórios/farmacologia , Encéfalo/patologia , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos
6.
Chem Commun (Camb) ; 56(7): 1022-1025, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31867592

RESUMO

A series of unsupported and supported vanadium phosphorus oxide catalysts were prepared by employing a new strategy, which significantly reduced the complexity of catalyst preparation. The greatly simplified catalyst fabrication benefits a greener and lower-cost process for practical applications. The currently fabricated systems showed ca. 90% target product(s) selectivity with a promising yield as well as catalyst durability.

7.
Sci Rep ; 9(1): 16988, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740731

RESUMO

A new type of supported vanadium phosphorus oxide (VPO) with self-phase regulation was simply fabricated (organic solvent free) for the first time by depositing the specific VPO precursor NH4(VO2)HPO4 onto the Siliceous Mesostructured Cellular Foams (MCF) with controlled activation. The resulting materials were found to be highly efficient and selective for sustainable acrylic acid (AA) plus methyl acrylate (MA) production via a condensation route between acetic acid (HAc) and formaldehyde (HCHO). A (AA + MA) yield of 83.7% (HCHO input-based) or a (AA + MA) selectivity of 81.7% (converted HAc-based) are achievable at 360 °C. The systematic characterizations and evaluations demonstrate a unique surface regulation occurring between the MCF and the NH4(VO2)HPO4 precursor. NH3 release upon activation of NH4(VO2)HPO4 precursor together with adsorption of NH3 by MCF automatically induces partial reduction of V5+ whose content is fine-tunable by the VPO loading. Such a functionalization simultaneously modifies phase constitution and surface acidity/basicity of catalyst, hence readily controls catalytic performance.

8.
Materials (Basel) ; 10(7)2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-28773178

RESUMO

In this study, the antimicrobial property and food package capability of polymethylpentene (PMP) substrate with silicon oxdie (SiOx) and organic silicon (SiCxHy) stacked layers deposited by an inductively coupled plasma chemical vapor deposition system were investigated. The experimental results show that the stacked pair number of SiOx/SiCxHy on PMP is limited to three pairs, beyond which the films will crack and cause package failure. The three-pair SiOx/SiCxHy on PMP shows a low water vapor transmission rate of 0.57 g/m²/day and a high water contact angle of 102°. Three-pair thin-film coated PMP demonstrates no microbe adhesion and exhibits antibacterial properties within 24 h. Food shelf life testing performed at 28 °C and 80% humidity reports that the three-pair thin-film coated PMP can enhance the food shelf-life to 120 h. The results indicate that the silicon-based thin film may be a promising material for antibacterial food packaging applications to extend the shelf-life of food products.

9.
Materials (Basel) ; 9(11)2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-28774074

RESUMO

A Ge67Cu33 (16 nm) layer and a Ge (3 nm)/Ge67Cu33 (16 nm) bilayer were grown by sputtering at room temperature and used as the recording films for write-once blue laser media. In comparison to the crystallization temperature of Ge in a GeCu film (380.7 °C-405.1 °C), the crystallization temperature of Ge in a Ge/GeCu bilayer could be further decreased to 333.7 °C-382.8 °C. The activation energies of Ge crystallization were 3.51 eV ± 0.05 eV and 1.50 eV ± 0.04 eV for the GeCu and the Ge/GeCu films, respectively, indicating that the Ge/GeCu bilayer possesses a higher feasibility in high-speed optical recording applications. Moreover, the lower activation energy would lead to a larger grain size of Ge crystallization in the Ge/GeCu bilayer after the annealing process. Between the as-deposited and the annealed states, the optical contrasts (@ 405 nm) of the GeCu and the Ge/GeCu films were 26.0% and 47.5%, respectively. This reveals that the Ge/GeCu bilayer is more suitable for the recording film of a write-once blu-ray disc (BD-R) in comparison with the GeCu film. Based on the dynamic tests performed for 2× and 4× recording speeds, the optimum jitter values of the BD-R with the Ge/GeCu recording film were 7.4% at 6.3 mW and 7.6% at 8.6 mW, respectively.

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