Occurrence and contribution of alkyl methoxypyrazines in wine tainted by Harmonia axyridis and Coccinella septempunctata

BACKGROUND: Ladybug taint (LBT) is a wine fault caused by the inadvertent incorporation of ladybeetles to the wine during the winemaking process. Harmonia axyridis, also known as the multicolored Asian lady‐beetle (MALB), was the only species considered responsible for causing the taint. A second species, Coccinella septempunctata (7 Spot), has recently also been implicated. The main objectives of this study were to identify and quantify the compounds associated with ladybug taint of white and red wine from these two Coccinellidae species (Harmonia axyridis and Coccinella septempunctata), and determine the most odor‐active compounds in LBT‐affected wines. RESULTS: Results show that Coccinellidae can contribute dimethyl, isopropyl, secbutyl and isobutyl methoxypyrazine to wine when they are processed with grapes, and that the methoxypyrazine composition varies between MALB and 7 Spot. Isopropyl methoxypyrazine is the major contributor to LBT in wines produced with these ladybeetle species, although secbutyl and isobutyl methoxypyrazine may contribute in MALB‐ and 7 Spot‐affected wines, respectively. Finally, dimethyl methoxypyrazine is reported for the first time in wines not affected by Coccinellidae; the global significance and prevalence of this compound in wine remains to be determined. CONCLUSION: Both Harmonia axyridis and Coccinella septempunctata can contribute alkyl methoxypyrazines, and particularly isopropyl methoxypyrazine, to wine at concentrations that can have a negative impact on wine quality. These findings will allow grape growers and winemakers to be more aware of the risks posed by 7 Spot beetles, and to take the appropriate preventative and remedial actions. Furthermore, this is the first time dimethyl methoxypyrazine is reported in wine, either as an endogenous or Coccinellidae‐derived odorant. © 2012 Society of Chemical Industry     

G proteins in carotid body chemoreception

This study explored the efficacy of hepatic arterial therapy, comparing both injection and infusion of 5-fluorouracil (5-FU) in prolonging the survival of 92 patients with recurrent unresectable hepatic metastasis from colorectal cancer. With respect to pretreatment carcinoembryonic antigen doubling time (CEA-DT), 56 patients were treated with intra-arterial injection, and 36 with intra-arterial infusion. In 21 patients with a CEA-DT of less than 40 days, the cumulative survival of patients treated with arterial injection was significantly longer than that of patients treated with arterial infusion. In 45 patients with a CEA-DT of 40-80 days, the survival curves of patients did not differ from each other. Of the remaining 26 patients with a CEA-DT of more than 80 days, those treated using arterial infusion had an excellent prognosis, in contrast to those treated using arterial injection, with statistical significance. CEA-DT may be useful when choosing a chemotherapy regimen, and may help to accurately establish the prognosis of patients with unresectable hepatic metastasis from colorectal cancer.     

机器翻译系统及翻译工具的开发和使用

本文综述了当前计算机翻译软件的需求和应用情况,着重讨论了如何设计翻译系统使其质量能达到可出版水平, 其中包括开发受限语言翻译系统, 翻译工作站, 及软件本地化。同时本文还涉及到如何开发非传统概念的翻译软件,特别是针对Web页面和其它应用在Internet上各类信息的翻译软件。本文还讨论了机器翻译未来的需要以及正在开发的一些系统。文中最后一部分比较了一下通过人译、机译,机助人译的方式达到的几种最合适的翻译方法。