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Characterization of defects in large 3D printed metals is critical but challenging. This study reports on the X-ray micro-computed tomography (micro-CT) examination of porosities in large-volume 3D-printed and heat-treated titanium (Ti–6Al–4V) alloys, together with their tensile properties and failure mechanisms. Titanium alloy powders were analyzed using scanning electron microscopy (SEM). Laser powder bed fusion (L-PBF) was used to print titanium alloy specimens vertically and horizontally, followed by stress-relieved heat treatment. Micro-CT imaging was performed on printed specimens of 10 × 20 mm3 (diameter × length) to determine their porosities, pore locations and size distributions using an industrial micro-CT system and relevant imaging software. Tensile testing of the processed specimens was conducted to determine their mechanical properties. Optical microscopy and SEM were used to examine the tension-induced failure mechanisms. The results show that porosities, pore sizes and locations were influenced by the build direction, resulting in different mechanical properties. Horizontal printing achieved higher tensile modulus, strength, ductility, resilience and toughness than vertical printing. Heat treatment did not change porosities in horizontally built specimens, but slightly reduced porosities for vertically built ones by 10%. This led to most mechanical properties nearly unchanged for the horizontally printed specimens but remarkably increased yield and tensile strength, and resilience, for the vertically printed ones. All tension-induced fractured surfaces contained pores, possible indicators of failure origins, which should be diminished in advanced processes for higher mechanical reliability.

Digital citizen participation is becoming increasingly important for improving government-citizen relationship, building active citizenship, and optimizing the efficiency of governments. Despite the potential, there are often far-reaching problems concerning the number and composition of participants, which often fall short of the expectations of local governments. Therefore, for e-participation to be successful, citizens must accept and use it. While numerous empirical studies have analyzed influencing factors such as the socio-demographic characteristics of citizens, the influence of the interaction between local governments and citizens within the procedures has been neglected. This article attempts to investigate the extent to which employee responsiveness and information quality influence citizens' acceptance of e-participation. Using an experimental design, the study confirms the influence of both factors.

Obesity confers an independent risk for carcinogenesis. Classically viewed as a genetic disease, owing to the discovery of tumor suppressors and oncogenes, genetic events alone are not sufficient to explain the progression and development of cancers. Tumor development is often associated with metabolic and immunological changes. In particular, obesity is found to significantly increase the mortality rate of liver cancer. As its role is not defined, a fundamental question is whether and how metabolic changes drive the development of cancer. In this review, we will dissect the current literature demonstrating that liver lipid dysfunction is a critical component driving the progression of cancer. We will discuss the involvement of inflammation in lipid dysfunction driven liver cancer development with a focus on the involvement of liver macrophages. We will first discuss the association of steatosis with liver cancer. This will be followed with a literature summary demonstrating the importance of inflammation and particularly macrophages in the progression of liver steatosis and highlighting the evidence that macrophages and macrophage produced inflammatory mediators are critical for liver cancer development. We will then discuss the specific inflammatory mediators and their roles in steatosis driven liver cancer development. Finally, we will summarize the molecular pattern (PAMP and DAMP) as well as lipid particle signals that are involved in the activation, infiltration and reprogramming of liver macrophages. We will also discuss some of the therapies that may interfere with lipid metabolism and also affect liver cancer development.