Piezo-catalysis was first used to degrade a nondye pollutant, 4-chlorophenol (4-CP). In this process, hydrothermally synthesized tetragonal BaTiO nano/micrometer-sized particles were used as the piezo-catalyst, and the ultrasonic irradiation with low frequency was selected as the vibration energy to cause the deformation of tetragonal BaTiO. It was found that the piezoelectric potential from the deformation could not only successfully degrade 4-chlorophenol but also effectively dechlorinate it at the same time, and five kinds of dechlorinated intermediates, hydroquinone, benzoquinone, phenol, cyclohexanone, and cyclohexanol, were determined. This is the first sample of piezo-dechlorination. Although various active species, including h, e, •H, •OH, •O, O, and HO, were generated in the piezoelectric process, it was confirmed by ESR, scavenger studies, and LC-MS that the degradation and dechlorination were mainly attributed to •OH radicals. These •OH radicals were chiefly derived from the electron reduction of O, partly from the hole oxidation of HO. These results indicated that the piezo-catalysis was an emerging and effective advanced oxidation technology for degradation and dechlorination of organic pollutants.

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1. Hydrogen sulphide (H(2)S) is a well-known cytotoxic gas. Recently, H(2)S has been shown to protect neurons against oxidative stress caused by glutamate, peroxynitrite and HOCl. Considerably lower H(2)S levels have been reported in the brain of Alzheimer's disease (AD) patients with accumulation of beta-amyloid (A beta). 2. The aim of present study was to explore the cytoprotection by H(2)S against A beta(25-35)-induced apoptosis and the molecular mechanisms underlying this effect in PC12 cells. 3. Our findings indicated that A beta(25-35) significantly reduced cell viability and induced apoptosis of PC12 cells, along with dissipation of the mitochondrial membrane potential (MMP) and overproduction of reactive oxygen species (ROS). 4. Sodium hydrosulphide (NaHS), an H(2)S donor, protected PC12 cells against A beta(25-35)-induced cytotoxicity and apoptosis not only by reducing the loss of MMP, but also by attenuating the increase in intracellular ROS. 5. The results of the present study suggest that the cytoprotection by H(2)S is related to the preservation of MMP and attenuation of A beta(25-35)-induced intracellular ROS generation. These findings could significantly advance therapeutic approaches to the neurodegenerative diseases that are associated with oxidative stress, such as AD.

Exogenous application of silicon (Si) in the form of sodium metasilicate reduced disease development caused by Penicillium expansum and Monilinia fructicola in sweet cherry fruit at 20 degrees C. The inhibition of fruit decay was correlated closely with Si concentrations. Silicon at concentrations of 1%, in combination with the biocontrol agent Cryptococcus laurentii at 1 x 10(7) cells per ml, provided synergistic effects against both diseases. Population dynamics of C. laurentii were stimulated by Si 48 h after the yeast treatment in the wounds of sweet cherry fruit. Silicon strongly inhibited spore germination and germ tube elongation of P. expansum and M. fructicola in vitro. Based on results with scanning electron microscopy, growth of both pathogens was significantly inhibited by Si in the wounds of sweet cherry fruit. Compared with the wounded water control, Si treatment induced a significant increase in the activities of phenylalanine ammonia-lyase, polyphenoloxidase, and peroxidase in sweet cherry fruit but did not increase the levels of lignin. Application of Si activated a cytochemical reaction and caused tissue browning near the site of wounding. Based on our studies, the improvement in biocontrol efficacy of antagonistic yeast when combined with Si may be associated with the increased population density of antagonistic yeast by Si, the direct fungitoxicity property of Si to the pathogens, and the elicitation of biochemical defense responses in fruit.

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We report on the dependence of the properties on the morphologies of sulfonated polymers 3a and 3b (η inh ) 0.65-1.18) with segments containing clusters of 6 and 12 sulfonic acid groups, respectively. The larger sulfonated clusters in polymers 3b resulted in higher proton conductivity and much better cell performance than polymers 3a. The highest power density of a fuel cell using 3a-1 (IEC ) 1.16 mequiv/g) and Nafion 117 was 0.23 and 0.21 W/cm 2 , respectively, at the effective work potential of 0.5 V, whereas that of 3b-1 (IEC ) 1.16 mequiv/g) was 0.29 W/cm 2 at even higher effective work potential of 0.6 V. The morphological structure of 3a-1 and 3b-1 was investigated by transmission electron microscopy (TEM) and compared with that of Nafion. TEM images of 3a-1 and 3b-1 revealed a phase separation similar to that of Nafion, which may explain their higher proton conductivities compared to those of randomly sulfonated copolymers.