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391.
Foraminiferal data were obtained from 66 samples of box cores on the southeastern Brazilian upper margin (between 23.8°–25.9°S and 42.8°–46.13°W) to evaluate the benthic foraminiferal fauna distribution and its relation to some selected abiotic parameters. We focused on areas with different primary production regimes on the southern Brazilian margin, which is generally considered as an oligotrophic region. The total density (D), richness (R), mean diversity ([`(H )] \overline{{H^{\prime } }} ), average living depth (ALD X ) and percentages of specimens of different microhabitats (epifauna, shallow infauna, intermediate infauna and deep infauna) were analyzed. The dominant species identified were Uvigerina spp., Globocassidulina subglobosa, Bulimina marginata, Adercotryma wrighti, Islandiella norcrossi, Rhizammina spp. and Brizalina sp.. We also established a set of mathematical functions for analyzing the vertical foraminiferal distribution patterns, providing a quantitative tool that allows correlating the microfaunal density distributions with abiotic factors. In general, the cores that fit with pure exponential decaying functions were related to the oligotrophic conditions prevalent on the Brazilian margin and to the flow of the Brazilian Current (BC). Different foraminiferal responses were identified in cores located in higher productivity zones, such as the northern and the southern region of the study area, where high percentages of infauna were encountered in these cores, and the functions used to fit these profiles differ appreciably from a pure exponential function, as a response of the significant living fauna in deeper layers of the sediment. One of the main factors supporting the different foraminiferal assemblage responses may be related to the differences in primary productivity of the water column and, consequently, in the estimated carbon flux to the sea floor. Nevertheless, also bottom water velocities, substrate type and water depth need to be considered.  相似文献   
392.
This study provides and meta‐analytically examines an organizing framework and theoretical model of work–family conflict. Results, based on 1080 correlations from 178 samples, indicate that work role stressors (job stressors, role conflict, role ambiguity, role overload, time demands), work role involvement (job involvement, work interest/centrality), work social support (organizational support, supervisor support, coworker support), work characteristics (task variety, job autonomy, family friendly organization), and personality (internal locus of control, negative affect/neuroticism) are antecedents of work‐to‐family conflict (WFC); while family role stressors (family stressors, role conflict, role ambiguity, role overload, time demands, parental demands, number of children/dependents), family social support (family support, spousal support), family characteristics (family climate), and personality (internal locus of control, negative affect/neuroticism) are antecedents of family‐to‐work conflict (FWC). In addition to hypothesized results, a revised model based on study findings indicates that work role stressors (job stressors, role conflict, role ambiguity, role overload) and work social support (organizational support, supervisor support, coworker support) are predictors of FWC; while family role stressors (family stressors, role conflict, role ambiguity, role overload), family involvement (family interest/centrality), family social support (family support, spousal support), and family characteristics (family climate) are predictors of WFC. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
393.
394.
The discharge of organic waste from the petrochemical industry into the Mercier lagoons caused major groundwater contamination. The objective of this study was to determine the immunotoxic potential of three groundwater wells at increasing distance from the incinerator dumping site (1.17, 2.74 and 5.40 km). Rainbow Trout were exposed to increasing concentrations of water from three groundwater wells for 14 days. Immunocompetence was characterized by phagocytosis, mitogen-stimulated proliferation of lymphocytes, cell cycle analysis and apoptosis. A significant increase in innate (phagocytosis) and specific immune response (B lymphocyte proliferation) was observed in trout exposed to water collected from the well at 2.74 km. However, phagocytosis activity was suppressed in groups at 1.17 and 5.40 km. The proportion of lymphocytes in S phase was significantly increased in groups at 2.74 and 5.40 kin, while lymphocytes in G0/G1 phase were decreased in all three exposure groups. Additionally, dexamethasone (DEX)-induced apoptosis of lymphocytes was significantly reduced in the group at 2.74 km, which suggests decreased lymphocyte turnover. Furthermore, the ratio of DEX- induced apoptosis/apoptosis was lower in the groups at 2.74 and 5.40 km. In summary, our experiments have shown that exposure to the mixture of organic compounds present in Mercier groundwater modulates phagocytosis and cell proliferation, disrupts the cell cycle and reduces the ratio of DEX- induced apoptosis/apoptosis. It is concluded that groundwater collected in the vicinity of an incinerator containment field could impact immunocompetence in fish.  相似文献   
395.
Sustainable management of landscapes with multiple competing demands such as the Ruaha Landscape is complex due to the diverse preferences and needs of stakeholder groups involved. This study uses conjoint analysis to assess the preferences of representatives from three stakeholder groups—local communities, district government officials, and non-governmental organizations—toward potential solutions of conservation and development tradeoffs facing local communities in the Ruaha Landscape of Tanzania. Results demonstrate that there is little consensus among stakeholders about the best development strategies for the Ruaha region. This analysis suggests a need for incorporating issues deemed important by these various groups into a development strategy that aims to promote conservation of the Ruaha Landscape and improve the livelihood of local communities.  相似文献   
396.
Journal of Material Cycles and Waste Management - Fruit production worldwide is over 675 million tons per year. Brazil is responsible for the production of 43.6 million tons of fruits per year,...  相似文献   
397.
Higher termites of the subfamily Macrotermitinae (fungus-growing termites) are known to build fungus gardens where a symbiotic fungus (Termitomyces sp.) is cultivated. The fungus grows on a substrate called fungus comb, a structure built with the termites’ own faeces. Here we present the first fossil fungus combs ever found in the world. They were extracted from 7-million-year-old continental sandstone (Chad basin). Fossilized fungus combs have an ovoid morphology with a more or less flattened concave base and a characteristic general alveolar aspect. Under lens, they display a typical millimetre-scale pelletal structure. The latter, as well as the general shape and alveolar aspect, are similar to the morphology of fungus combs from extant fungus-growing termites.  相似文献   
398.
A contaminated soil was collected in a field adjacent to a derelict As((III)) smelter in Reppel (Bocholt, Belgium). A single soil treatment (% by soil weight) based on either iron grit (SS, 1%), beringite (B, 5%), or iron grit (1%) + beringite (5%) (BSS) was applied. Untreated and treated Reppel soils and a control soil were placed in lysimeters inside a greenhouse and cropped annually. The efficiency of soil treatments in decreasing As and metals in exposure sources and restoring soil functions was assessed 6 years after the treatments commenced. Decreases in extractable Cd, Mn, Zn and As occurred in the BSS soil. Only BSS treatment reduced both As and metal concentrations in leachates. BSS treatment produced best growth of lettuce and cabbage, the highest shoot and pod yields for dwarf bean, the lowest As, Cd and Zn concentrations in plant tissues, and partly restored Rhizobium nodulation on bean roots. The epigeic earthworm (Dendrobaena octaedra) could only survive in the BSS soil. Depurated living worms from the BSS soil had Cd concentration similar to those in control worms, but higher As, Ca, Fe, and Zn concentrations. Based on physiologically based extraction test (PBET), As bioaccessibility was reduced from 12% (untreated soil) to 7.4% (BSS) and 3% (SS), but only the SS treatment decreased the bioaccessibility of Cd (-30%) and Pb (-35%). The range of chemical and biological indicators suggested that BSS amendment was the most effective treatment for restoration of normal soil functions 6 years after initial treatment of the Reppel soil.  相似文献   
399.
Jaouani A  Tabka MG  Penninckx MJ 《Chemosphere》2006,62(9):1421-1430
In order to decolourise olive oil mill wastewaters (OOMW) efficiently, production and differential induction of ligninolytic enzymes by the white rot Coriolopsis polyzona, were studied by varying growth media composition and/or inducer addition. Among various possible inducers, veratryl alcohol appeared to be the most efficient to enhance specific productions of lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase by a factor of 18.5, 20.8 and 55, respectively. Ligninolytic enzymes were better produced in glucose based medium with a low nitrogen level (2.2 mM) under O2 atmosphere. The addition of 5 mM veratryl alcohol resulted in a maximal production of LiP, whereas maximal MnP and laccase were obtained at 10 mM. LiP production was totally repressed in presence of 100 microM Mn2+. The extrapolation of these conditions on OOMW based media was carried out at different effluent dilutions and the possible role of the different ligninolytic enzymes in OOMW decolourisation was studied. A better effluent decolourisation was obtained under LiP induction condition (5 mM veratryl alcohol) than when LiP was repressed (100 microM Mn2+). Furthermore, high levels of laccase had a detrimental effect on OOMW decolourisation concomitant to the formation of soluble polymeric aromatic compounds.  相似文献   
400.
The Ouémé River is one of the most important rivers in the Republic of Bénin. It is 510 km long and its catchment drains 75% of the country. In this study, organochlorine and organophosphorous pesticide residues were measured in more than 35 sediment samples collected on nine locations along the Ouémé River from upstream to downstream. Except for one location, Tanéka-Koko, all areas were contaminated by more than 20 pesticides. Organochlorine pesticides identified in sediment samples included pp'-DDE, op'-DDD, pp'-DDD, op'-DDT, pp'-DDT, alpha-endosulfan, beta-endosulfan, endosulfan sulphate, alpha-HCH, beta-HCH, lindane, aldrin, dieldrin, endrin, telodrin, isodrin, cis- and trans-heptachlorepoxide, hexachlorbutadiene, hexachlorobenzene and octachlorostyrene. The organophosphorous pesticide chlorpyrifos, used in a new formulation to protect cotton, was also identified. In some areas, the concentrations of organochlorine pesticides in the sediment of the Ouémé River exceeded environmental quality standards and are reason for concern.  相似文献   
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