The silicon active sites driven by oxygen vacancies in iron silicate for activating peroxymonosulfate.

Most metal sites and some non-metallic sites such as carbon and nitrogen are usually considered to be traditional active sites during peroxymonosulfate (PMS) activation. However, as an important non-metallic element, the actual role of silicon (Si) in PMS activation still remains unclear. In this work, taking iron silicate (FeSi) as an example, the role of the Si region in PMS activation was clearly revealed. The experiments and density functional theory (DFT) calculation results showed that besides the traditional Fe sites, the Si also played a non-negligible role during PMS activation. In FeSi containing oxygen vacancies (Ovac), Fe-Si was the active site instead of Fe-Fe. The Bard charge results implied that the presence of Ovac tuned the electronic properties of FeSi, making the Si participate in PMS activation. This work deepened understanding of the role of Si in silicates for PMS activation and provided a theoretical basis for the development of excellent Si-based catalysts.

Retracted: Long-term copper toxicity in apple trees (Malus pumila Mill) and bioaccumulation in fruits.

The following article from Environmental Toxicology, 'Long-term Copper Toxicity in Apple Trees (Malus pumila Mill) and Bioaccumulation in Fruits' by Bai-Ye Sun, Shi- Hong Kan, Yan-Zong Zhang, Jun Wu, Shi-Huai Deng, Chun-Sheng Liu and Gang Yang, published online on January 15, 2010 in Wiley InterScience (www.interscience.wiley.com; DOI: 10.1002/tox.20565), has been retracted by agreement between the authors, the journal Editor in Chief, Dr. Paul Tchounwou, and Wiley Periodicals, Inc. The retraction has been agreed at the request of the authors due to overlap with 'Copper Toxicity and Bioaccumulation in Chinese Cabbage (Brassica pekinensis Rupr.)' by Zhi-Ting Xiong and Hai Wang, published in Environmental Toxicology, Volume 20, pages 188-194, 2005.

Clinical relevance of using autofluorescence bronchoscopy and white light bronchoscopy in different types of airway lesions.

OBJECTIVES: The aim of this study was to evaluate the sensitivity and specificity of autofluorescence bronchoscopy (AFB) according to the macroscopic appearance of airway lesions under white light bronchoscopy (WLB). MATERIALS AND METHODS: The bronchoscopic findings of 708 patients, who were pathologically and clinically diagnosed with airway lesions and underwent both WLB and AFB, were analyzed. RESULTS: We recruited 708 patients for this study, of which 336 (47.5%) had benign lesions; 300 and 254 benign lesions were detected by AFB (specificity, 89.3%) and WLB (specificity, 75.6%), respectively. In 372 (52.5%) patients with bronchiogenic carcinoma, 356 and 235 lesions were identified by AFB (sensitivity, 95.7%) and WLB (sensitivity, 63.2%), respectively. The sensitivity and specificity of AFB for diagnosing lung cancer were higher than those of WLB (P < 0.05). Moreover, AFB showed high sensitivity for detecting lung cancer in cases in which WLB revealed hyperplasia, infiltration, and stenosis (P < 0.05). CONCLUSIONS: AFB combined with WLB could effectively improve the diagnosis of airway lesions.

Certain antioxidant enzymes and lipid peroxidation of radish (Raphanus sativus L.) as early warning biomarkers of soil copper exposure.

Copper (Cu) is a major heavy metal contaminant with various anthropogenic and natural sources. Recently, using biomarkers to monitor the effects of pollutants has attracted increased interest. Pot culture experiments using radish (Raphanus sativus L.) was performed to investigate Cu phytotoxic effects on antioxidant enzymes and other early warning biomarkers of soil Cu exposure. Under low dose Cu stress (lower than the EC10, Cu concentration reducing root length by 10%), activity and isozyme expression of superoxide dismutase (SOD), catalase (CAT), and peroxidases (POD) increased significantly; no significant variations in chlorophyll, carotenoid, and malondialdehyde (MDA) content in leaves and toxic symptoms were observed. Under a slightly higher Cu stress (close to the EC10), activity and isozyme expression of SOD and MDA content were enhanced significantly; those of CAT and POD decreased due to an inverted U-shape dose response. Chlorophyll content remained unchanged. Thus, antioxidant enzymes and MDA content are more sensitive to Cu stress, showing significant variations ahead of chlorophyll and toxic symptoms under Cu stress (lower than about 200 mg kg(-1) soil). Thus, the joint monitoring of antioxidant enzymes and MDA content of R. sativus can be used as biomarkers of soil Cu contamination.