Background and Aim:  A number of studies have shown that hepatitis virus infections may be associated with cholangiocarcinoma (CC). However, the relationship between hepatitis B virus (HBV) infection and CC, especially intrahepatic cholangiocarcinoma (ICC), is still controversial. Methods:  Relevant studies were identified by searching PUBMED, EMBASE and Web of Science Datebases up to September 2011. Pooled risk estimates were calculated using a random‐effects model. Potential sources of heterogeneity were performed by subgroup analyses. A total of 18 papers were included in this meta‐analysis. Results:  The pooled risk estimate of all studies showed a statistically significant increased risk of CC among individuals with HBV infection (rate ratio [RR]: 2.66; 95% confidence interval [CI]: 1.97, 3.60). Compared with those without HBV infection, persons with HBV infection had an increased risk of intra‐CC (ICC) (RR: 3.42; 95% CI: 2.46, 43.74), extrahepatic CC (OR: 1.46; 95% CI: 0.98, 2.17), and CC (OR: 2.03; 95% CI: 1.15, 3.56). In a subgroup analysis of HBV infection and risk of ICC, the pooled risk estimate of studies in Asians (RR: 3.63; 95% CI: 2.56, 5.13) was higher than that in non‐Asians (RR: 1.93; 95% CI: 0.78, 4.76). A Begg funnel plot and Egger test revealed no evidence for publication bias. Conclusions:  This meta‐analysis shows that HBV is associated with increased risk of CC, especially for ICC. Further investigation is needed to focus on the mechanism by which HBV may be involved in the pathogenesis of CC.

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The Knudsen pump (KP) is a kind of micro-pump that can form thermally induced flows induced by temperature fields in rarefied gas environments. It has the advantages of having no moving parts, simple structure, easy construction and extension, a wide range of energy sources, and low energy consumption. With the development of Micro/Nano Electro Mechanical Systems (MEMS/NEMS), extensive studies have been conducted on KPs, and the applications of KPs have widened. In order to obtain efficient flow fields in KPs, it is necessary to adopt modern computational methods for simulation and analysis. In many circumstances, the simulation and experimental results have good agreement. However, there seems to be no comprehensive review on KPs at present. In this paper, KPs are first defined and classified according to the flow mechanisms of the thermally induced flows. Then, the three aspects of configurations, performance, and applications of KPs in the current state of research are reviewed and analyzed. Finally, the current problems of KP are discussed, and some suggestions are provided for future research and applications.

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Aiming at improving the food quality during microwave process, this article mainly focused on the numerical simulation of shape effect, which was evaluated by microwave power absorption capability and temperature distribution uniformity in a single sample heated in a domestic microwave oven. This article only took the electromagnetic field and heat conduction in solid into consideration. The Maxwell equations were used to calculate the distribution of microwave electromagnetic field distribution in the microwave cavity and samples; then the electromagnetic energy was coupled as the heat source in the heat conduction process in samples. Quantitatively, the power absorption capability and temperature distribution uniformity were, respectively, described by power absorption efficiency (PAE) and the statistical variation of coefficient (COV). In addition, we defined the comprehensive evaluation coefficient (CEC) to describe the usability of a specific sample. In accordance with volume or the wave numbers and penetration numbers in the radial and axial directions of samples, they can be classified into different groups. And according to the PAE, COV, and CEC value and the specific need of microwave process, an optimal sample shape and orientation could be decided.