A universal but simple procedure for identifying the α, β and γ phases in PVDF using FTIR is proposed and validated. An integrated quantification methodology for individual β and γ phase in mixed systems is also proposed.

Oxidative stress and inflammation are well-documented pathological factors in alcoholic liver disease (ALD). Artichoke (Cynara scolymus L.) is a healthy food and folk medicine with anti-oxidative and anti-inflammatory properties. This study aimed to evaluate the preventive effects of ethanolic extract from artichoke against acute alcohol-induced liver injury in mice. Male Institute of Cancer Research mice were treated with an ethanolic extract of artichoke (0.4, 0.8, and 1.6 g/kg body weight) by gavage once daily. Up to 40% alcohol (12 mL/kg body weight) was administered orally 1 h after artichoke treatment. All mice were fed for 10 consecutive days. Results showed that artichoke extract significantly prevented elevated levels of aspartate aminotransferase, alanine aminotransferase, triglyceride, total cholesterol, and malondialdehyde. Meanwhile, the decreased levels of superoxide dismutase and glutathione were elevated by artichoke administration. Histopathological examination showed that artichoke attenuated degeneration, inflammatory infiltration and necrosis of hepatocytes. Immunohistochemical analysis revealed that expression levels of toll-like receptor (TLR) 4 and nuclear factor-kappa B (NF-κB) in liver tissues were significantly suppressed by artichoke treatment. Results obtained demonstrated that artichoke extract exhibited significant preventive protective effect against acute alcohol-induced liver injury. This finding is mainly attributed to its ability to attenuate oxidative stress and suppress the TLR4/NF-κB inflammatory pathway. To the best of our knowledge, the underlying mechanisms of artichoke on acute ALD have been rarely reported.

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Effective transformation from paraelectric to a high fraction of ferroelectric phase is crucial to produce piezoelectric materials with a high piezoelectric constant for broad applications. In polyvinylidene fluoride (PVDF) thin films, both mechanical stretching and electric poling processes have been found to be critical in the a / b phase transformation. However, in PVDF fibers fabricated by the electrospinning process, the roles of mechanical stretching and electric poling have not been well explored. Here, the properties of PVDF fibers from electrospinning and forcespinning, a mechanical spinning process without electric poling, have been characterized and analyzed by FTIR and XRD spectroscopic techniques. The results show that pure mechanical stretching in the forcespun fibers can result in a high fraction of the all-trans b-phase, at 95%. Electrospun fibers from the same material system, on the other hand, can also reach a high fraction of b-phase, at approximately 99%. These results preliminarily demonstrate that mechanical stretching is the main reason for b-phase induction in PVDF fibers. Further experiments performed in this work show that higher wt% of PVDF, lower polymer solution supply rate, and more uniformly mixed solvent systems facilitate achieving a higher level of ferroelectric b-phase in electrospun PVDF fibers.

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