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991.
Maciej A. Pszczolkowski Kevin Durden Juleah Marquis Sonny B. Ramaswamy John J. Brown 《Die Naturwissenschaften》2009,96(5):621-624
Neonate larvae of codling moth, Cydia pomonella (L.), modify their behavior in the presence of saccharin, monosodium glutamate (MSG), or L(+)-2-amino-4-phosphonobutyric
acid (L-AP4) by commencing their feeding earlier. Previously published pharmacological analysis demonstrated that phagostimulatory
effects of MSG and L-AP4 (which elicit umami taste sensation in humans) are reversed by adenylate cyclase activator and phosphodiesterase
inhibitor. In this study, by measuring the time needed to start ingestion of foliage treated with mixtures of phagostimulants
and signal transduction modulators, we show that phagostimulatory effects of l-aspartate (the third hallmark umami substance) are also abolished by both adenylate cyclase activator and phosphodiesterase
inhibitor, but not by phospholipase C inhibitor. However, stimulatory effects of hemicalcium saccharin were affected only
by phospholipase C inhibitor. The results suggest that codling moth neonates use different transduction pathways for perception
of hemicalcium saccharin and umami. 相似文献
992.
Monika Djerf-Pierre John Cokley Louise J. Kuchel 《Environmental Communication: A Journal of Nature and Culture》2016,10(5):634-655
Australia and Sweden display very different institutional settings and contexts for the production of environmental journalism. This empirical study examined how two major quality newspapers in Sweden and Australia have framed renewable energy as an environmental, political, scientific, economic and civil society issue. A deductive, quantitative methodological approach was used to identify dominant frames and actors in articles in The Australian (Australia) and Dagens Nyheter (Sweden) between October 2010 and June 2011 2010/2011. The findings suggest that the attention given to different types of renewable energy in the two newspapers and how issues were framed was contingent on the domestication of the discussion of renewable energy in the two countries. Reporting on renewable energy in both newspapers was characterized by a focus on “elite” actors and economic frames, the absence of civil society frames and negative (The Australian) or ambiguous (Dagens Nyheter) environmental frames. The study extends our understanding of the contextual conditions that enable and limit journalists when reporting environmental issues. 相似文献
993.
This study examined the factors associated with financial support in old age from three primary mechanisms-personal savings,family support,and social insurance-to explore the implications for the future development of China’s rural social welfare system.Cross-sectional surveys of 1392 young and middle-aged rural residents were conducted in July and August2012.The results showed that while social insurance was increasingly acceptable,personal savings and family support still had fundamental value.Combining the three mechanisms,the rural old-age welfare system presented nontraditional features.China’s new rural endowment insurance is discussed as a means to address the need for financial support among the rural aging population. 相似文献
994.
Jakob Abermann Birger Hansen Magnus Lund Stefan Wacker Mojtaba Karami John Cappelen 《Ambio》2017,46(1):3-11
We investigated air temperature and pressure gradients and their trends for the period 1996–2014 in Greenland and compared these to other periods since 1958. Both latitudinal temperature and pressure gradients were strongest during winter. An overall temperature increase up to 0.15 °C year?1 was observed for 1996–2014. The strongest warming happened during February at the West coast (up to 0.6 °C year?1), weaker but consistent and significant warming occurred during summer months (up to 0.3 °C year?1) both in West and East Greenland. Pressure trends on a monthly basis were mainly negative, but largely statistically non-significant. Compared with other time windows in the past six decades, the period 1996–2014 yielded an above-average warming trend. Northeast Greenland and the area around Zackenberg follow the general pattern but are on the lower boundary of observed significant trends in Greenland. We conclude that temperature-driven ecosystem changes as observed in Zackenberg may well be exceeded in other areas of Greenland. 相似文献
995.
John Cosgrove Frank Doyle John Littlewood Paul Wilgeroth 《International Journal of Sustainable Engineering》2017,10(4-5):233-240
AbstractEnergy management in small to medium enterprises (SMEs) remains undeveloped due to competing priorities and a lack of specialist knowledge. However considerable savings can be demonstrated where companies take the time to investigate their energy use. Savings of over 20% can be achieved through changes to operational and behavioural practice. Additional benefits, such as improved production tracking and improved maintenance, can been seen which add to the value in undertaking an energy monitoring and targeting (M&T) plan. The method described involves the application of a series of ‘virtuous’ cycles of engagement and energy savings that can be applied from the highest factory level right down to a specific machine. The analysis of overall energy use from utility bills and the visualisation of typical machine power profiles aid in understanding the drivers of energy consumption and in engaging management in energy efficiency. The monitoring of specific machines in production highlights the significant consumption of electricity during non-productive times. The development of energy performance indicators is described for product variations which can be useful in tendering for business and selecting optimum production pathways. The approach is illustrated with data from a case study of a precision engineering SME based in Limerick, Ireland. 相似文献
996.
997.
Chow JC Watson JG Lowenthal DH Magliano KL 《Journal of the Air & Waste Management Association (1995)》2005,55(8):1158-1168
Evaporative loss of particulate matter (with aerodynamic diameter < 2.5 microm, [PM2.5]) ammonium nitrate from quartz-fiber filters during aerosol sampling was evaluated from December 3, 1999, through February 3, 2001, at two urban (Fresno and Bakersfield) and three nonurban (Bethel Island, Sierra Nevada Foothills, and Angiola) sites in central California. Compared with total particulate nitrate, evaporative nitrate losses ranged from < 10% during cold months to > 80% during warm months. In agreement with theory, evaporative loss from quartz-fiber filters in nitric acid denuded samplers is controlled by the ambient nitric acid-to-particulate nitrate ratio, which is determined mainly by ambient temperature. Accurate estimation of nitrate volatilization requires a detailed thermodynamic model and comprehensive chemical measurements. For the 14-month average of PM2.5 acquired on Teflon-membrane filters, measured PM2.5 mass was 8-16% lower than actual PM2.5 mass owing to nitrate volatilization. For 24-hr samples, measured PM2.5 was as much as 32-44% lower than actual PM2.5 at three California Central Valley locations. 相似文献
998.
The majority of oestrogenic material excreted from humans and wildlife, and therefore released into sewers, is in a conjugated form. However, the finding of “free” oestrogens in sewage effluent suggests that these metabolites are somehow converted back into an active form, before or during passage through a sewage treatment process. When male fathead minnows (Pimephales promelas) were continuously exposed to oestradiol-3-glucuronide, in a continuous-flow system, it demonstrated no inherent oestrogenic activity. However, when fish were exposed to effluent generated from laboratory simulations of sewage treatment processes, to which had been added oestradiol-3-glucuronide, oestrogenic activity was observed, suggesting microbial activity was capable of degrading the steroid metabolite into a more potent oestrogen. Oestrogenic potency was determined by measuring changes in plasma vitellogenin (egg yolk precursor) concentrations and gonadosomatic index. The results suggest that inactive metabolites of steroids are very readily biotransformed into biologically active oestrogens. 相似文献
999.
Olchawa E Bzowska M Stürzenbaum SR Morgan AJ Plytycz B 《Environmental pollution (Barking, Essex : 1987)》2006,142(2):373-381
Three-day dermal exposure of Dendrobaena veneta to metal ions differentially disrupts the immunocompetence/pathogen balance. Zn does not accumulate in the earthworm body, Cu accumulation is temperature-independent while Cd accumulation is stronger at 22 degrees C than at 10 degrees C. During in vitro incubation with metal ions at 22 degrees C, growth of coelom-derived bacteria is enhanced by Zn, but significantly or almost completely inhibited by Cu or Cd. In contrast, under in vivo conditions at 22 degrees C, bacterial load is decreased only after Cd exposure, but increased after Zn and Cu exposures. At 10 degrees C bacteria growth is almost completely inhibited in all groups except Cu-treated animals. Coelomocyte number is unaffected in animals exposed to Zn, but significantly decreased after exposure to Cd (at 22 degrees C) and Cu (at 22 degrees C and 10 degrees C) with concomitant changes of amoebocyte-to-eleocyte ratio in favour of amoebocytes. Metal exposure up-regulates expression of metallothioneins in coelomocytes, mainly amoebocytes. 相似文献
1000.