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We recently demonstrated common oxidants simply coupled with ZVI to continuously drive the accelerated Fe 0 corrosion and hence achieve fast and very efficient removal of heavy metals and metalloids from groundwater. In this study, we aimed first to answer a basic question of the oxidant dosage theoretically required to sequester a certain amount of selenite. The specific ratio of oxidant dosage to Se(IV) removal, which reflected the theoretically minimal oxidant dosage required to sequester one mole of Se(IV), was almost independent of the initial Se(IV) concentration but significantly affected by the difference in oxidant species. To sequester one mole of Se(IV), the minimum dosage of the required oxidant was calculated to be 3.94–4.09 for NaClO, 3.90–4.33 for H 2 O 2 , and 3.29–3.54 for KMnO 4 , respectively. Simultaneous aeration increased the removal efficiency of Se(IV) and substantially reduced the required dosage of oxidants. To form a strong contrast with very limited Se(IV) removal by ZVI alone, the coupling of NaClO and H 2 O 2 into the ZVI system remarkably enhanced the performance of Se(IV) removal during the long term fixed-bed experiments with a real groundwater background. The ZVI columns coupled by NaClO and H 2 O 2 steadily treated 10,000 volumes (BV) of real groundwater. X-ray adsorption near edge structure (XANES) demonstrated that more than 85% of the selenium was reduced to Se 0 and Se 2− , with Se 0 as the dominant selenium species sequestered in the solid phase. Synchrotron-based scanning transmission soft X-ray microscopy (STXM) explicitly revealed the ubiquitous spatial distribution of selenium in the corrosion products and hence demonstrated a high accessibility of these corrosion products to selenite. [ABSTRACT FROM AUTHOR]

Multi-drug-resistant Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis were isolated from the tissue samples of a giant panda. The E. coli strain SH-YH-DH that we isolated carried a self-transferable plasmid associated with multi-drug-resistant genes ( blaCTX-M-55, blaTEM-1, sul1, floR, strB, aac(6′)-Ib, and tetA/R). This strain exhibited phenotypic resistance to gentamicin, cefotaxime, ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, and tetracycline. We report the participation of multi-drug-resistant E. coli in a extraintestinal polyinfection in giant pandas and that further research is warranted to pay attention to the threat of multi-drug-resistant bacteria in the panda population. [ABSTRACT FROM AUTHOR]

Teachers' conceptions of assessment are a significant indicator of teacher assessment literacy. This study contextualized pre-service teachers' conceptions of assessment in Chinese second language education. An exploratory factor analysis generated eight first-order factors and the following confirmatory factor analysis found a hierarchical model, reflecting a noticeable influence of prior learning experiences and official assessment regimes on conceptions. A follow-up latent profile analysis showed three profiles. Improvement-oriented was the most prevalent profile, but more than 40% of the participants were categorized as negative. The study substantiated the need to develop an integrative and balanced understanding of assessment in teacher education to prepare pre-service teachers for teaching in international contexts. [ABSTRACT FROM AUTHOR]

Purpose: To compare the accuracy of a Kinect-Optical navigation system with an electromagnetic (EM) navigation system for percutaneous liver needle intervention. Materials and methods: Five beagles with nine artificial tumors were used for validation. The Veran IG4 EM navigation system and a custom-made Kinect-Optical navigation system were used. Needle insertions into each tumor were conducted with these two guidance methods. The target positioning error (TPE) and the time cost of the puncture procedures were evaluated. Results: A total of 18 needle insertions were performed to evaluate the navigation accuracy of the two guidance approaches. The targeting error was 6.78 ± 3.22 mm and 8.72 ± 3.5 mm for the Kinect-Optical navigation system and the EM navigation system, respectively. There is no statistically significant difference in the TPE between the Kinect-Optical navigation system and the EM navigation system ( p = 0.229). The processing time with the Kinect-Optical system (10 min) is similar to that of the Veran IG4 system (12 min). Conclusions: The accuracy of the Kinect-Optical navigation system is comparable to that of the EM navigation system. [ABSTRACT FROM AUTHOR]

ABSTRACT Background and objective Statins have been widely used in inflammatory diseases including asthma, because of their anti-inflammatory and immunomodulatory properties. It has been shown that simvastatin induces autophagy and cell death in some circumstances. However, the possible cross-talk between simvastatin and autophagic processes in lung disease is largely unknown. Thus, we investigated the impact of simvastatin on airway inflammation and airway remodelling and the possible relationship of these processes to a simvastatin-induced autophagic pathway in mouse models of asthma. Methods Ovalbumin ( OVA)-sensitized and challenged mice were treated with simvastatin and sacrificed. The autophagy-related proteins Atg5, LC3B and Beclin1 were quantified, as well as the autophagy flux in bronchial smooth muscle cells ( BSMCs). The relationship between airway inflammation and the autophagic process was investigated. Results We show that simvastatin treatment mediates activation of autophagy in BSMCs, which is correlated with airway inflammation and airway remodelling in mouse models of asthma. Simvastatin increases autophagy-related protein Atg5, LC3B and Beclin1 expression and autophagosome formation in lung tissue. Simvastatin-induced autophagy is associated with increased interferon-gamma ( IFN-γ) and decreased IL-4, IL-5 and IL-13 cytokines production in BSMCs, as well as reversed extracellular matrix ( ECM) deposition. In contrast, autophagy inhibitor 3-methyladenine (3- MA) eliminates the therapeutic effect of simvastatin. Conclusion These findings demonstrate that simvastatin inhibits airway inflammation and airway remodelling through an activated autophagic process in BSMCs. We propose a crucial function of autophagy in statin-based therapeutic approaches in asthma. [ABSTRACT FROM AUTHOR]