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1.
Sensors (Basel) ; 23(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37765798

RESUMO

This research presents a dual-pronged bibliometric and systematic review of the integration of phase change materials (PCM) in asphalt pavements to counteract the urban heat island (UHI) effect. The bibliometric approach discerns the evolution of PCM-inclusion asphalt research, highlighting a marked rise in the number of publications between 2019 and 2022. Notably, Chang'an University in China has emerged as a leading contributor. The systematic review addresses key questions like optimal PCM types for UHI effect mitigation, strategies for PCM leakage prevention in asphalt, and effects on mechanical properties. The findings identify polyethylene glycols (PEGs), especially PEG2000 and PEG4000, as prevailing PCM due to their wide phase-change temperature range and significant enthalpy during phase transitions. While including PCM can modify asphalt's mechanical attributes, such mixtures typically stay within performance norms. This review emphasises the potential of PCM in urban heat management and the need for further research to achieve optimal thermal and mechanical balance.

2.
J Mech Behav Biomed Mater ; 84: 225-234, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29803137

RESUMO

OBJECTIVES: The aim of this study was to evaluate the influence of a surface conditioning technique using laser ablation and acid etching on PEEK substrate on its bonding strength to a resin cement. MATERIALS AND METHODS: Cylindrical specimens of unfilled PEEK, 30% glass fiber reinforced PEEK and 30% carbon fiber reinforced PEEK were separated in four groups according to the following surface treatments: acid etching with H2SO4, laser ablation with 200 µm holes spaced 400 µm apart (D2E4), laser ablation with 200 µm holes spaced 600 µm apart (D2E6), and laser ablation (D2E4) followed by acid etching. A dual-curing resin cement (Allcem CORE) was then applied to the PEEK surface. Specimens were aged in distilled water at 37 °C for 24 h. Shear bond strength tests were performed to the fracture of the samples. Two-way ANOVA statistical analysis was performed with a significance level of 0.05. Scanning electron microscopy analysis was performed to analyse the conditioned and fracture surfaces. RESULTS: SEM images of the test interfaces showed that the resin cement could not flow in the holes designed by the laser ablation on the PEEK surface. The shear bond strength of PEEK to resin cement was not improved by the surface modification of the PEEK. Also, there was a statistically significant decrease in shear bond strength for unfilled PEEK specimens. On carbon or glass reinforced PEEK, the change was not significant. SEM images of the fracture surfaces revealed that the failure mode was mainly adhesive. CONCLUSIONS: Although laser ablation promoted the PEEK surface modification by the formation of retentive holes, the test resin cement could not thoroughly flow on the rough modified surfaces to establish an effective mechanical interlocking. That negatively affected the shear bonding strength of PEEK to the resin cement. Further studies should be carried out to increase the bonding between PEEK and resin cements.


Assuntos
Lasers , Cimentos de Resina/química , Resistência ao Cisalhamento , Benzofenonas , Carbono/química , Vidro/química , Cetonas , Polietilenoglicóis , Polímeros , Propriedades de Superfície
3.
J Pharmacol Exp Ther ; 358(2): 315-23, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27194479

RESUMO

Rheumatoid arthritis is an inflammatory autoimmune condition, and tumor necrosis factor-α (TNF-α) plays an important role in its pathophysiology. In vitro, (E)-N'-(3,4-dimethoxybenzylidene)-N-methylbenzohydrazide (LASSBio-1359) has exhibited anti-TNF-α properties, and in vivo these effects are mediated via activation of adenosine receptor. This work investigates the antinociceptive action of LASSBio-1359 in murine models of acute and chronic inflammatory pain. Male mice received an intraperitoneal injection of LASSBio-1359 and then were evaluated in formalin- and carrageenan-induced paw edema assays. Complete Freund's adjuvant (CFA) was used to induce a mouse model of monoarthritis. These mice were treated with LASSBio-1359 by oral gavage to evaluate thermal and mechanical hyperalgesia. TNF-α and inducible nitric oxide synthase (iNOS) expression as well as histologic features were analyzed. The time of reactivity to formalin in the neurogenic phase was reduced from 56.3 ± 6.0 seconds to 32.7 ± 2.2 seconds and 23.8 ± 2.6 seconds after treatment with LASSBio-1359 at doses of 10 mg/kg and 20 mg/kg, respectively. A reversal of the antinociceptive action of LASSBio-1359 was observed in the inflammatory phase after treatment with ZM 241385 [4-(2-[7-amino-2-(2-furly)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl)phenol], an adenosine A2A antagonist. Carrageenan-induced thermal and mechanical hyperalgesia were reduced after treatment with LASSBio-1359. Similarly, CFA-induced thermal and mechanical hyperalgesia were reduced after treatment with LASSBio-1359 (25 and 50 mg/kg). Levels of TNF-α and iNOS expression increased in the monoarthritis model and were normalized in animals treated with LASSBio-1359, which was also associated with beneficial effects in the histologic analysis. These results suggest that LASSBio-1359 represents an alternative treatment of monoarthritis.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Benzamidas/farmacologia , Hidrazonas/farmacologia , Dor/tratamento farmacológico , Agonistas do Receptor Purinérgico P1/farmacologia , Receptores Purinérgicos P1/metabolismo , Doença Aguda , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Artrite Reumatoide/complicações , Benzamidas/uso terapêutico , Doença Crônica , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hidrazonas/uso terapêutico , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Hiperalgesia/metabolismo , Inflamação/complicações , Masculino , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Dor/etiologia , Dor/metabolismo , Agonistas do Receptor Purinérgico P1/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
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