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141.
Abstract: Ingestion of anthropogenic debris by marine species has been documented extensively; fewer studies have attempted to quantify the sublethal effects caused by debris ingestion. One potential sublethal effect is reduced nutrient gains from diets diluted by consumption of debris. Post-hatchling and juvenile loggerhead sea turtles ( Caretta caretta ) consume substantial quantities of debris. We evaluated the effects of dietary dilution on voluntary intake in post-hatchling loggerheads to assess their ability to compensate for the presence of inert diluents in their diet by increasing dry mass intakes to maintain nutrient gains. Mean daily intakes of dry mass did not increase significantly with dietary dilution, so intakes of energy and nitrogen on a 50% dilution diet were significantly lower than on a 10% dilution diet. Therefore, post-hatchling loggerheads have an extremely limited ability to compensate for dietary dilution and would experience sublethal effects from decreased energy and nitrogen gains on dilute diets. Decreased nutrient intakes have serious conservation implications because of possible decreased growth rates, longer developmental periods at sizes most vulnerable to predation, depleted energy reserves, reduced reproductive output, and decreased survivorship.  相似文献   
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Oceanographic processes play a significant role in shaping the genetic structure of marine populations, but it is less clear whether they affect genetic differentiation of highly mobile vertebrates. We used microsatellite markers and mtDNA control region sequences to investigate the spatial genetic structure of short-beaked common dolphins (Delphinus delphis) in southeastern Australia, a region characterised by complex oceanographic conditions associated with the East Australian Current (EAC). A total of 115 biopsy samples of dolphins were collected from six localities spanning approximately 1,000 km of the New South Wales (NSW) coastline. We found evidence for contrasting genetic diversity and fine-scale genetic structure, characterised by three genetically differentiated populations with varying levels of admixture. Spatial genetic structure was not explained by a model of isolation by distance, instead it coincides with main patterns of oceanographic variation along the EAC. We propose that common dolphins along the EAC may be adapted to three water masses recently characterised in this region.  相似文献   
144.
用溶剂萃取-白土精制法对4种废机油进行了再生研究,萃取过程剂油质量比为3∶1,萃取温度为60℃,减压蒸馏回收溶剂。白土精制过程中白土质量为油质量的10%,精制温度为185℃。精制后4种废机油的密度、凝点、黏度、闪点、酸值等都有不同程度的改善。  相似文献   
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Membrane fouling is a primary concern in membrane bioreactors (MBRs) in wastewater treatment because it strongly affects both system stability and economic feasibility. A mathematical model was developed in this study for membrane fouling in submerged MBR systems for wastewater treatment, in which both reversible and irreversible fouling were quantified. While mixed liquor suspended solids are the major components of the reversible fouling layer, dissolved organic matter is thought to be the key foulant, in particular, responsible for the long-term irreversible fouling of the filtration unit. The model was calibrated (parameter identification) with a set of operational data from a pilot MBR and then verified with other independent operational data from the MBR. The good agreement between theoretical predictions and operational data demonstrates that the outlined modeling concept can be successfully applied to describe membrane fouling in submerged MBR systems.  相似文献   
147.
Loeys-Dietz syndrome is a recently described autosomal dominant disorder with cardinal manifestations in cardiovascular, craniofacial and skeletal systems. Although the disease has some phenotypic overlap with Marfan syndrome, the disease, that is caused by mutations in the transforming growth factor beta-receptor 1 (TGFBR1) or transforming growth factor beta-receptor 2 (TGFBR2) genes, presents many distinctive features and a particularly aggressive cardiovascular course. We describe prenatal identification of an aortic root aneurysm in a fetus of 19 week of gestation as an early marker of Loeys-Dietz syndrome. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT: The distribution of sediment physical characteristics, sediment phosphorus (P) pools, and laboratory‐based rates of P release from the sediments were used to identify regions and dosage for alum treatment in Wind Lake, Wisconsin. Using variations in sediment moisture content, we identified an erosional zone at depths < 1.4 m and an accumulation zone at depths > 2.6 m. Mean concentrations of porewater P, loosely‐bound P, iron‐ and aluminum‐bound P, and mean rates of P release from sediments under anoxic conditions were high in the accumulation zone compared to sediment P characteristics in the erosional zone, indicating focusing of readily mobilized sediment P pools from shallow regions and accumulation to deep regions. We determined that a future alum treatment for control of internal P loading would be most effective at depths > 2.6 in the accumulation zone. The mean rate of anoxic P release from sediments encountered in the accumulation zone (8.3 mg m‐2 d‐1) was used in conjunction with a summer anoxic period of 122 d, and a treatment area of 1.6 km2 to estimate an internal P load of 1,600 kg to be controlled. Our results suggest that an understanding of the distribution of sediment P pools and P fluxes in lakes provides a strategy for estimating alum dosage and application areas.  相似文献   
150.
Combating climate change and protecting the environment is a significant topic amongst political leaders and concerned citizens across the globe. The degree to which individuals perceive green issues as important is connected to their politics, those subscribing to conservative ideologies being less supportive of pro-environmental initiatives and less concerned about climate change than those endsorsing liberal ideologies. Examining political ideology as a uni- and bi-dimensional construct, the present research investigated whether political liberals (vs. conservatives), those higher (vs. lower) in right-wing authoritarianism, and those higher (vs. lower) in social dominance orientation differ in their perceptions of the morality of green behaviours. In Studies 1 (= 200) and 2 (= 150), liberal (vs. conservative) ideologies related to perceiving pro-environmental behaviours as more moral. Further, in Study 2, the relation between ideology and perceptions of green behaviours as moral was explained by positive feelings associated with the self engaging in green behaviours.  相似文献   
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