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931.
932.
Hyung Chul Kim Timothy J. Wallington Sherry A. Mueller Bert Bras Tina Guldberg Francisco Tejada 《Journal of Industrial Ecology》2016,20(5):1122-1133
Literature data for vehicle life cycle water consumption are limited and contradictory; there are no published estimates of vehicle life cycle water withdrawal. To place future discussions of sustainable mobility on a firmer technical basis, we report the results of a cradle‐to‐grave assessment of water withdrawal and water consumption for the gasoline internal combustion engine vehicle (ICEV) and battery electric vehicle (BEV) variants of the 2012 Ford Focus. U.S. average life cycle water withdrawal and consumption of 531 and 131 cubic meters (m3), respectively, for a lifetime driving distance of 160,000 miles are estimated for the Focus ICEV using E10 gasoline. Employing our upper bound of water use in oil refinery operations and corn and ethanol production increases the life cycle withdrawal and consumption to 1,570 and 761 m3, respectively. The U.S. average life cycle water withdrawal for the Focus BEV is 3,770 m3 (7 times that for the ICEV, reflecting the large volume of cooling water required during electricity generation), whereas the water consumption is 170 m3 (comparable to that for the ICEV). Vehicle use is the most significant phase of the life cycle with fuel production, accounting for 49% of water withdrawal and 82% of water consumption for the ICEV. For the BEV, fuel (electricity) production accounts for 92% of life cycle water withdrawal and 85% of consumption. The results highlight the importance of renewable and sustainable fuels and increased vehicle energy efficiency in providing sustainable mobility. 相似文献
933.
Light exposure leads to reorganization of microglomeruli in the mushroom bodies and influences juvenile hormone levels in the honeybee
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Christina Scholl Ying Wang Markus Krischke Martin J. Mueller Gro V. Amdam Wolfgang Rössler 《Developmental neurobiology》2014,74(11):1141-1153
Honeybees show a remarkable behavioral plasticity at the transition from nursing inside the hive to foraging for nectar and/or pollen outside. This plasticity is important for age‐related division of labor in honeybee colonies. The behavioral transition is associated with significant volume and synaptic changes in the mushroom bodies (MBs), brain centers for sensory integration, learning, and memory. We tested whether precocious sensory exposure to light leads to changes in the density of synaptic complexes [microglomeruli (MG)] in the MBs. The results show that exposure to light pulses over 3 days induces a significant decrease in the MG density in visual subregions (collar) of the MB. Earlier studies had shown that foragers have increased levels of juvenile hormone (JH) co‐occurring with a decrease of vitellogenin (Vg). Previous work further established that RNAi‐mediated knockdown of vg and ultraspiracle (usp) induced an upregulation of JH levels, which can lead to precocious foraging. By disturbing both Vg and JH pathways using gene knockdown of vg and usp, we tested whether the changes in the hormonal system directly affect MG densities. Our study shows that MG numbers remained unchanged when Vg and JH pathways were perturbed, suggesting no direct hormonal influences on MG densities. However, mass spectrometry detection of JH revealed that precocious light exposure triggered an increase in JH levels in the hemolymph (HL) of young bees. This suggests a dual effect following light exposure via direct effects on MG reorganization in the MB calyx and a possible positive feedback on HL JH levels. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 74: 1141–1153, 2014 相似文献
934.
Randall TA Dwyer RA Huitema E Beyer K Cvitanich C Kelkar H Fong AM Gates K Roberts S Yatzkan E Gaffney T Law M Testa A Torto-Alalibo T Zhang M Zheng L Mueller E Windass J Binder A Birch PR Gisi U Govers F Gow NA Mauch F van West P Waugh ME Yu J Boller T Kamoun S Lam ST Judelson HS 《Molecular plant-microbe interactions : MPMI》2005,18(3):229-243
935.
Steffen Fritz Linda See Ian McCallum Liangzhi You Andriy Bun Elena Moltchanova Martina Duerauer Fransizka Albrecht Christian Schill Christoph Perger Petr Havlik Aline Mosnier Philip Thornton Ulrike Wood‐Sichra Mario Herrero Inbal Becker‐Reshef Chris Justice Matthew Hansen Peng Gong Sheta Abdel Aziz Anna Cipriani Renato Cumani Giuliano Cecchi Giulia Conchedda Stefanus Ferreira Adriana Gomez Myriam Haffani Francois Kayitakire Jaiteh Malanding Rick Mueller Terence Newby Andre Nonguierma Adeaga Olusegun Simone Ortner D. Ram Rajak Jansle Rocha Dmitry Schepaschenko Maria Schepaschenko Alexey Terekhov Alex Tiangwa Christelle Vancutsem Elodie Vintrou Wu Wenbin Marijn van der Velde Antonia Dunwoody Florian Kraxner Michael Obersteiner 《Global Change Biology》2015,21(5):1980-1992
A new 1 km global IIASA‐IFPRI cropland percentage map for the baseline year 2005 has been developed which integrates a number of individual cropland maps at global to regional to national scales. The individual map products include existing global land cover maps such as GlobCover 2005 and MODIS v.5, regional maps such as AFRICOVER and national maps from mapping agencies and other organizations. The different products are ranked at the national level using crowdsourced data from Geo‐Wiki to create a map that reflects the likelihood of cropland. Calibration with national and subnational crop statistics was then undertaken to distribute the cropland within each country and subnational unit. The new IIASA‐IFPRI cropland product has been validated using very high‐resolution satellite imagery via Geo‐Wiki and has an overall accuracy of 82.4%. It has also been compared with the EarthStat cropland product and shows a lower root mean square error on an independent data set collected from Geo‐Wiki. The first ever global field size map was produced at the same resolution as the IIASA‐IFPRI cropland map based on interpolation of field size data collected via a Geo‐Wiki crowdsourcing campaign. A validation exercise of the global field size map revealed satisfactory agreement with control data, particularly given the relatively modest size of the field size data set used to create the map. Both are critical inputs to global agricultural monitoring in the frame of GEOGLAM and will serve the global land modelling and integrated assessment community, in particular for improving land use models that require baseline cropland information. These products are freely available for downloading from the http://cropland.geo-wiki.org website. 相似文献
936.
AN9, a petunia glutathione S-transferase required for anthocyanin sequestration, is a flavonoid-binding protein 总被引:18,自引:0,他引:18
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AN9 is a glutathione S-transferase from petunia (Petunia hybrida) required for efficient anthocyanin export from the site of synthesis in the cytoplasm into permanent storage in the vacuole. For many xenobiotics it is well established that a covalent glutathione (GSH) tag mediates recognition of molecules destined for vacuolar sequestration by a tonoplast-localized ATP-binding cassette pump. Here we inquired whether AN9 catalyzes the formation of GSH conjugates with flavonoid substrates. Using high-performance liquid chromatography analysis of reaction mixtures containing enzyme, GSH, and flavonoids, including anthocyanins, we could detect neither conjugates nor a decrease in the free thiol concentration. These results suggest that no conjugate is formed in vitro. However, AN9 was shown to bind flavonoids using three assays: inhibition of the glutathione S-transferase activity of AN9 toward the common substrate 1-chloro 2,4-dinitrobenzene, equilibrium dialysis, and tryptophan quenching. We conclude that AN9 is a flavonoid-binding protein, and propose that in vivo it serves as a cytoplasmic flavonoid carrier protein. 相似文献
937.
938.
939.
T2Rs function as bitter taste receptors 总被引:49,自引:0,他引:49
Bitter taste perception provides animals with critical protection against ingestion of poisonous compounds. In the accompanying paper, we report the characterization of a large family of putative mammalian taste receptors (T2Rs). Here we use a heterologous expression system to show that specific T2Rs function as bitter taste receptors. A mouse T2R (mT2R-5) responds to the bitter tastant cycloheximide, and a human and a mouse receptor (hT2R-4 and mT2R-8) responded to denatonium and 6-n-propyl-2-thiouracil. Mice strains deficient in their ability to detect cycloheximide have amino acid substitutions in the mT2R-5 gene; these changes render the receptor significantly less responsive to cycloheximide. We also expressed mT2R-5 in insect cells and demonstrate specific tastant-dependent activation of gustducin, a G protein implicated in bitter signaling. Since a single taste receptor cell expresses a large repertoire of T2Rs, these findings provide a plausible explanation for the uniform bitter taste that is evoked by many structurally unrelated toxic compounds. 相似文献
940.
Fujita Y Taniguchi J Uchikawa M Endo M Hata K Kubo T Mueller BK Yamashita T 《Cell death and differentiation》2008,15(10):1593-1608
The repulsive guidance molecule (RGM) is a membrane-bound protein that has diverse functions in the developing central nervous system. Identification of neogenin as a receptor for RGM provided evidence of its cell death-inducing activity in the absence of RGM. Here, we show that the serine/threonine kinase death-associated protein kinase (DAPK) is involved in the signal transduction of neogenin. Neogenin interacts with DAPK and reduces DAPK autophosphorylation on Ser308 in vitro. Neogenin-induced cell death is abolished in the presence of RGM or by blocking DAPK. Although neogenin overexpression or RGM downregulation in the chick neural tube in vivo induces apoptosis, coexpression of the dominant-negative mutant or small-interference RNA of DAPK attenuates this proapoptotic activity. Thus, RGM/neogenin regulates cell fate by controlling the DAPK activity. 相似文献