In China, excessive use of nitrogen fertilizers in glasshouses leads to nitrate accumulations in soil and plants, which then limits productivity. Melatonin, an evolutionarily highly conserved molecule, has a wide range of functions in plants. We analyzed the effects of melatonin pretreatment on the growth, mineral nutrition, and nitrogen metabolism in cucumber (Cucumis sativus L. "Jin You No. 1") when seedlings were exposed to nitrate stress. An application of 0.1 mmol/L melatonin significantly improved the growth of plants and reduced their susceptibility to damage due to high nitrate levels (0.6 mol/L) during the ensuing period of stress treatment. Although excess nitrate led to an increase in the concentrations of nitrogen, potassium, and calcium, as well as a decrease in levels of phosphorus and magnesium, exogenous melatonin generally had the opposite effect except for a further rise in calcium concentrations. Pretreatment also significantly reduced the accumulations of nitrate nitrogen and ammonium nitrogen and enhanced the activities of enzymes involved in nitrogen metabolism. Expression of Cs-NR and Cs-GOGAT, two genes that function in that metabolism, was greatly down-regulated when plants were exposed to 0.6 mol/L nitrate, but was up-regulated in plants that had received the 0.1 mmol/L melatonin pretreatment. Our results are the first evidence that melatonin has an important role in modulating the composition of mineral elements and nitrogen metabolism, thereby alleviating the inhibitory effect on growth normally associated with nitrate stress.

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Aims Methadone maintenance treatment has been made available in China in response to the rapid spread of HIV, but high rates of dropout and relapse are problematic. The aim of this study was to apply and test if a contingency management (or motivational incentives) intervention can improve treatment retention and reduce drug use. Design Random assignment to usual care with (n=160) or without (n=159) incentives during a 12-week trial. Incentives participants earned draws for a chance to win prizes on two separate tracks targeting opiate-negative urine sample or consecutive attendance; the number of draws increased with continuous abstinence or attendance. Setting Community-based methadone maintenance clinics in Shanghai and Kunming. Participants The sample was 23.8 % female, mean age was 38, mean years of drug use was 9.4, and 57.8 % had injected drugs in the past 30 days. Measurements Treatment retention and negative drug urine. Findings Relative to the treatment-as-usual (control) group, better retention was observed among the Incentives group in Kunming (44% vs. 75%), but no difference was found in Shanghai (90% vs. 86%). Submission of negative urine samples was more common among the Incentive group than the usual care (74% vs. 68% in Shanghai, 27% vs. 18% in Kunming), as was the longest duration of sustained abstinence (7.7 wks vs. 6.5 in Shanghai, 2.5 vs. 1.6 in Kunming). The average total prize amount was 371 Yuan (or $55) per participant (527 for Shanghai vs. 216 in Kunming). Conclusions Contingency management improves treatment retention and drug abstinence in methadone maintenance treatment clinics in China, although there can be considerable site differences in magnitude of effects.

Pressure/proximity sensing as the essential function of electronic skin (e-skin) has become an emerging technological goal for new-generation electronic devices in a wide variety of application fields, for example, smart electronics, human− machine interaction, and prosthetics. However, the current research lacks pressure/ proximity detection of the stretched e-skin, which ignores the key elastic characteristic of skin and hinders the development of e-skin. Here, the pressure/ proximity detection of the transparent e-skin in the stretching state is demonstrated based on poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS)/ single-walled carbon nanotube (SWCNT). The high transparency of the e-skin realizes the visual imperception for wearable electronic systems. The perfect combination of stretchable SWCNT and highly conductive PEDOT:PSS endows the sensors with high stretchability and high discrimination capability toward strain, providing an effective way to overcome the interference of strain to realize accurate pressure/proximity detection of stretched e-skin at different strains.

OPRM1, which codes for the mu-opioid receptor, is the most frequently studied candidate gene for opioid dependence. Despite numerous allelic association studies, no definitive conclusion has been reached regarding the role of OPRM1 polymorphisms in determining risk for opioid dependence. We attempted to resolve this by conducting a family-based association study and meta-analysis which may be more robust and powerful, respectively, than traditional case-control analyses. First, we genotyped three single nucleotide polymorphisms (SNPs) of OPRM1 in 1208 individuals from 473 Han Chinese families ascertained on the basis of having two or more siblings with DSM-IV-defined opioid dependence. The Val6Ala and Arg111His SNPs were detected, but with low minor allele frequencies (0.002 and 0.001, respectively). The Asn40Asp SNP was more informative (minor allele frequency: 0.419), but no significant evidence was observed for either a dominant (p=0.810) or additive (p=0.406) effect of this polymorphism on risk for opioid dependence. In addition, a meta-analysis of case-control studies of opioid dependence was performed, and found a similar lack of evidence for an association with the Asn40Asp SNP (p=0.859). Although a role of OPRM1 polymorphisms in determining risk for opioid dependence cannot be entirely discounted, a major contribution of the Asn40Asp polymorphism seems unlikely. Further analysis is warranted in samples from specific ancestral groups. In addition, it is critical that other OPRM1 variants, including all haplotype-tagging and amino-acid-coding SNPs, be tested for an influence on risk for opioid dependence, since the Asn40Asp polymorphism is only one of several hundred known mutations in the gene.

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Despite identification of WRKY family genes in numerous plant species, a little is known about WRKY genes in watermelon, one of the most economically important fruit crops around the world. Here, we identified a total of 63 putative WRKY genes in watermelon and classified them into three major groups (I-III) and five subgroups (IIa-IIe) in group II. The structure analysis indicated that ClWRKYs with different WRKY domains or motifs may play different roles by regulating respective target genes. The expressions of ClWRKYs in different tissues indicate that they are involved in various tissue growth and development. Furthermore, the diverse responses of ClWRKYs to drought, salt, or cold stress suggest that they positively or negatively affect plant tolerance to various abiotic stresses. In addition, the altered expression patterns of ClWRKYs in response to phytohormones such as, ABA, SA, MeJA, and ETH, imply the occurrence of complex cross-talks between ClWRKYs and plant hormone signals in regulating plant physiological and biological processes. Taken together, our findings provide valuable clues to further explore the function and regulatory mechanisms of ClWRKY genes in watermelon growth, development, and adaption to environmental stresses.

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