Shaping and Structuring Supramolecular Gels

Supramolecular gels assemble via non-covalent interactions between low-molecular-weight gelators (LMWGs). The gels form a solid-like nanoscale network spanning a liquid-like continuous phase, translating molecular-scale information into materials performance. However, gels based on LMWGs are often difficult to manipulate, easily destroyed and have poor rheological performance. The recurring image of newly-discovered supramolecular gels is that of an inverted vial showing that the gel can support its own weight against gravity. Such images reflect the limitation that these gels simply fill the vessel in which they are made, with limited ability to be shaped. This property prevents supramolecular gels from having the same impact as polymer gels, despite greater synthetic tunability, reversibility and bio/environmental compatibility. In this Review, we evaluate strategies for imposing different shapes onto supramolecular gels and for patterning structures within them. We review fabrication methods including moulding, self-healing, 3D printing, photopatterning, diffusion and surface-mediated patterning. We discuss gelator chemistries amenable to each method, highlighting how a multi-component approach can aid shaping and structuring. Supramolecular gels with defined shapes, or patterned structures with precisely-controlled compositions, have the potential to intervene in applications such as tissue engineering and nanoscale electronics, as well as opening-up new technologies

A review on electric vehicles and their interaction with smart grids: the case of Brazil

This work provides a comprehensive literature review to evaluate the expected impacts of the introduction of electric vehicles into the power electric system with smart grid, examining the case of Brazil. Previous studies point out to different impact levels with the introduction of electric vehicles in the country’s electric grid, varying from small impacts for substitution of 10 % of the fleet, to potential difficulties if more than 20 % of the fleet is replaced. Electric vehicles offer significant advantages over their internal combustion engine powered vehicles counterparts, including the higher efficiency and performance of the electric motor, reduced pollution emissions during operation, and decreased noise levels. The current disadvantages lie mainly with the higher vehicle and battery costs, relatively long battery-charging period required, limited battery lifetime, and the need to increase market availability. Brazil’s electricity generation capacity is primarily based on clean and renewable energy (hydropower, wind, biomass), providing the preferred approach to charge electric vehicles with minimal carbon and other pollutant emissions. With the introduction of smart grids in the country’s electricity distribution structure, electric vehicles also provide a pathway (with renewable energy options) toward cleaner electricity, leveling the power demand cycle, and lowering the need to add costly central station generation by integrating them into the grid itself during periods when they are not used for transportation. However, careful studies must be conducted mainly due to the need to increase electric power generation to meet existing and imminent demands

Subcellular Localization of APE1/Ref-1 in Human Hepatocellular Carcinoma: Possible Prognostic Significance

APE1/Ref-1, normally localized in the nucleus, is a regulator of the cellular response to oxidative stress. Cytoplasmic localization has been observed in several tumors and correlates with a poor prognosis. Because no data are available on liver tumors, we investigated APE1/Ref-1 subcellular localization and its correlation with survival in 47 consecutive patients undergoing hepatocellular carcinoma (HCC) resection. APE1/Ref-1 expression was determined by immunohistochemistry in HCC and surrounding liver cirrhosis (SLC) and compared with normal liver tissue. Survival probability was evaluated using Kaplan-Meier curves (log-rank test) and Cox regression. Cytoplasmic expression of APE1/Ref-1 was significantly higher in HCC than in SLC (P = 0.00001); normal liver showed only nuclear reactivity. Patients with poorly differentiated HCC showed a cytoplasmic expression three times higher than those with well-differentiated HCC (P = 0.03). Cytoplasmic localization was associated with a median survival time shorter than those with negative cytoplasmic reactivity (0.44 compared with 1.64 years, P = 0.003), and multivariable analysis confirmed that cytoplasmic APE1/Ref-1 localization is a predictor of survival. Cytoplasmic expression of APE1/Ref-1 is increased in HCC and is associated with a lower degree of differentiation and a shorter survival time, pointing to the use of the cytoplasmic localization of APE1/Ref-1 as a prognostic marker for HCC