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991.
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Margaret Byrne Carole P. Elliott Colin J. Yates David J. Coates 《Conservation Genetics》2008,9(1):97-105
Pollen dispersal was investigated in five remnant populations of Eucalyptus wandoo, a dominant insect-pollinated tree in the fragmented agricultural region of southern Western Australia. Paternity analysis
using six microsatellite loci identified a pollen source for 45% of seedlings, and the remainder were assumed to have arisen
from pollen sources outside the stands. Outcrossing was variable, ranging from 52 to 89%, and long distance pollen dispersal
was observed in all populations with up to 65% of pollen sourced from outside the populations over distances of at least 1 km.
Modelling dispersal functions for pollination events within the two larger populations showed little difference between the
four two-parameter models tested and indicated a fat-tailed dispersal curve. Similarity of direct and indirect historical
estimates of gene flow indicates maintenance of gene flow at levels experienced prior to fragmentation. The study revealed
extensive long distance pollen dispersal in remnant patches of trees within a fragmented agricultural landscape in the southern
temperate region and highlighted the role of remnant patches in maintaining genetic connectivity at the landscape scale. 相似文献
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Rebecca C. Brown Stanley Barone Jr. Carole A. Kimmel 《Birth defects research. Part B, Developmental and reproductive toxicology》2008,83(6):511-521
This overview paper provides the historical context for the incorporation of lifestage‐specific concerns in human health risk assessment, briefly explains the process employed in a lifestage framework for risk assessment, and discusses the scientific rationale for how utilizing lifestage data will strengthen the overall risk assessment process. This risk assessment approach will add value by: (1) providing a more complete evaluation of the potential for vulnerability at different lifestages, including a focus on the underlying biological events and incorporation of mode of action information related to different critical developmental periods; (2) evaluating the potential for toxicity during all lifestages after early lifestage exposure; (3) reviewing the importance of integrating exposure information and adverse health effects across lifestages; and (4) serving as a basis to extend some aspects of the children's health risk assessment framework to all lifestages. Birth Defects Res (Part B), 2008. © 2008 Wiley‐Liss, Inc. 相似文献
996.
Fyferling M Uribelarrea JL Goma G Molina-Jouve C 《Bioprocess and biosystems engineering》2008,31(6):595-604
Oxygen transfer performances in intensive microbial cultures are compared with those occuring in coalescing and non-coalescing mineral media. E. coli fed-batch cultures are carried out in a 22 L bioreactor. Biomass concentrations of 80 g(DW) L(-1) are reached, with oxygen consumption rates of up to 0.6 mol L(-1) h(-1). To achieve these high transfer performances, dissipated power e reaches 35 kW m(-3). The hold-up in the culture broth and in the corresponding supernatant matches the non-coalescing mineral medium. Oxygen transfer coefficients, K (L) a in mineral media, and K (T) in the culture broth, are compared. K (T), calculated online from a gas balance method, excesses 1 s(-1). Yet, for given values of e, K (T) is 4-8 times lower than K (L) a determined in the non-coalescing mineral medium. The cell activity modifies the chemical medium properties and reduces the oxygen transfer conductance, as in a non-coalescing ionic medium containing surfactant. 相似文献
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Lim J Sanders RA Yeager RL Millsap DS Watkins JB Eells JT Henshel DS 《Journal of biochemical and molecular toxicology》2008,22(4):230-239
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a potent developmental teratogen inducing oxidative stress and sublethal changes in multiple organs, provokes developmental renal injuries. In this study, we investigated TCDD-induced biochemical changes and the therapeutic efficacy of photobiomodulation (670 nm; 4 J/cm(2)) on oxidative stress in chicken kidneys during development. Eggs were injected once prior to incubation with TCDD (2 pg/g or 200 pg/g) or sunflower oil vehicle control. Half of the eggs in each dose group were then treated with red light once per day through embryonic day 20 (E20). Upon hatching at E21, the kidneys were collected and assayed for glutathione peroxidase, glutathione reductase, catalase, superoxide dimutase, and glutathione-S-transferase activities, as well as reduced glutathione and ATP levels, and lipid peroxidation. TCDD exposure alone suppressed the activity of the antioxidant enzymes, increased lipid peroxidation, and depleted available ATP. The biochemical indicators of oxidative and energy stress in the kidney were reversed by daily phototherapy, restoring ATP and glutathione contents and increasing antioxidant enzyme activities to control levels. Photobiomodulation also normalized the level of lipid peroxidation increased by TCDD exposure. The results of this study suggest that 670 nm photobiomodulation may be useful as a noninvasive treatment for renal injury resulting from chemically induced cellular oxidative and energy stress. 相似文献
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Carole A Estabrooks Linda Derksen Connie Winther John N Lavis Shannon D Scott Lars Wallin Joanne Profetto-McGrath 《Implementation science : IS》2008,3(1):1-22