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Liver is very sensitive to environmental contaminants such as pesticides, it being the first target of toxicity of a substance. The objective of this study was to investigate the possible effects of the insecticide imidacloprid (IMI) on the liver of Oreochromis niloticus according concentrations used for growing sugarcane. A semi-quantitative analysis of histopathological alterations of IMI on liver was performed by light microscopy and cellular labeling of heat shock proteins (HSP70) by immunohistochemistry. The most common changes in liver at all concentrations of IMI were hydropic degeneration, pyknotic nuclei, and loss of cell limits. Steatosis and increased levels of HSP70 were detected in hepatocytes with the highest concentration of IMI. In conclusion, the tested concentrations of IMI induced histopathological changes in the liver of O. niloticus and active defence mechanisms to maintain the morphophysiological integrity of the liver. This insecticide has a toxicity potential for these fish, which is a non-target organism of its action.  相似文献   
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Abstract

Fu monisin B1 (FB1) is a mycotoxin commonly found in maize and maize-based products. Ingestion of FB1-contaminated causes a myriad of dose- and species-dependent toxic effects to human and animal health. In the present study we evaluated the effects of FB1 (8?mg/kg, i.p. for 4?days) on body weight and oxidative stress parameters in the liver, kidney and lung of C57BL/6 male mice. No changes in the organ-to-body weight ratio, organ-to-adrenal gland weight ratio or organ-to-brain weight ratio were found. On the other hand, FB1 exposure increased NPSH levels in liver and lungs whereas decreased FRAP content in liver and kidneys. Levels of TBARS, ascorbic acid and NOx content were not altered by FB1. In summary, four days of FB1 exposure are sufficient to disrupt antioxidant defenses in liver, kidneys and lungs of C57BL/6 male mice without concomitant changes in organs weight.  相似文献   
255.
One of the objectives of the new State of Croatia, as a Mediterranean country oriented towards tourism, is safety of its air traffic. The frequency of use of Zagreb airport is currently 688 flights, or about 20000 passengers a week. In 1996, research was carried out at the airport concerning air traffic safety with respect to the presence of birds on the airfield. Biological methods, in which birds were chased away by means of trained birds of prey, were used. For the Zagreb airport experiment nine birds involving three different species: Falco peregrinus, Accipiter gentilis and Falco cherrug were utilised. The results showed that the air traffic safety on Zagreb airport with regard to possible bird-plane strikes improved.Other bird clearing methods, applied over the 1987–1996 period also reduced bird-plane interferences but were noted to be less effective. With the biological, bird of prey method, 100% temporary clearance was achieved. Habitat modification, which involved removal from the airport vicinity of all factors attractive to the birds, only removed 20–30% of the birds, but this was of a more permanent nature. Use of fire-arms achieved a 80–90% temporary bird clearance. A combination of all three methods would appear to be most effective and measures for further monitoring for safe air traffic movement at Zagreb airport are proposed.  相似文献   
256.

New finds of bones of the Egyptian Mongoose (Herpestes ichneumon), one from Portugal and one from Spain, were directly 14C dated to the first century AD. While the Portuguese specimen was found without connection to the Chalcolithic occupation of the Pedra Furada cave where it was recovered, the Spanish find, collected in the city of Mérida, comes from a ritual pit that also contained three human and 40 dog burials. The finds reported here show that the Egyptian mongoose, contrary to the traditional and predominant view, did not first arrive in the Iberian Peninsula during the Muslim occupation of Iberia. Instead, our findings are consistent with the hypothesis that the species was first introduced by the Romans, or at least sometime during the Roman occupation of Hispania. Therefore, radiocarbon dating of new archaeological finds of bones of the Egyptian Mongoose (Herpestes ichneumon) in the Iberian Peninsula push back the confirmed presence of the species in the region by approximately eight centuries, as the previously oldest dated record is from the ninth century. With these new dates, there are now a total of four 14C dated specimens of Egyptian mongooses from the Iberian Peninsula, and all of these dates fall within the last 2000 years. This offers support for the hypothesis that the presence of the species in Iberia is due to historical introductions and is at odds with a scenario of natural sweepstake dispersal across the Straits of Gibraltar in the Late Pleistocene (126,000–11,700 years ago), recently proposed based on genetic data.

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257.
In this paper, we compare the populations of the Lusitanian toadfish Halobatrachus didactylus along the Portuguese shore, using a putative fragment of the mitochondrial control region and the first intron of the S7 ribosomal protein gene. This demersal species ranges from the tropical West African coast to the Iberian Peninsula and the Mediterranean, having its northern limit in the Tagus River. For the putative control region, a single haplotype occurs in all fish from Tagus and Sado (the location immediately to the south) with a clear increase in diversity to the South, peaking at Algarve (south Portugal). The data seem to point to a very recent Holocenic colonization of Tagus and Sado from the South (possibly Algarve). We suggest that even small oscillations in sea surface temperature (SST) may cause local extinctions and subsequent recolonizations in populations of thermophilic fish that are at the cold limit of their distributions.  相似文献   
258.
This work studies the introduction of cleaner production (CP) in the tank farm of the Pancevo Oil Refinery. From 2003 to 2008, substantial investments in storage technology and equipment were made in order to minimize the emissions of volatile organic compounds (VOCs). This article analyzes the effects of the CP activities using a model of tank farm emissions before and after reconstruction. US EPA TANKS software was used in order to develop a comprehensive model of the tank farm emissions. The year 2006 was accepted as representative for the analyses and related technical and production data as well as meteorological information were employed in the development of the model. The results show that the total VOC emissions were 37.6% lower after reconstruction and that the emissions of the major pollutant benzene were decreased by 62.7%. The effects of the CP activities were analyzed through the reduction of ecological damage, elements related to the operating costs, liability issues and the company's image. Future tank farm reconstruction activities in the Oil Refinery, Pancevo were proposed and their environmental effects predicted. An indicator of the expected decrease in VOC pollution was developed and quantified, with the aim of its use for quick calculations in similar cases.  相似文献   
259.
The number and diversity of civil society or third sector sustainability organisations (TSSOs) have increased in recent decades. TSSOs play a prominent role in local approaches to sustainability. However, the contributions made by TSSOs are not fully understood, beyond a limited suite of quantifiable outputs and impacts. In this qualitative study, we examine how four TSSOs from two Australian regions, Tasmania and Queensland's Sunshine Coast, contribute to social transformation beyond discrete outputs. We examine the operation, ethos, scope and influence of these organisations over time. In so doing, we identify three common ways in which these organisations facilitate social change: by (i) enhancing social connectivity through boundary work; (ii) mobilising participatory citizenship and (iii) contributing to social learning. We conclude that TSSOs contribute significantly to the systemic social conditions that enable change for sustainability and the development of community resilience and well-being, but do so in ways undervalued by existing metrics, formal evaluation processes and funding models. Clearer recognition of, and strategic emphasis on, these qualitative contributions to social transformation is vital in ensuring that TSSOs remain viable and effective over the long term.  相似文献   
260.

A southern Italian area that is characterized by large outcrops of rocks that are rich in titanium oxide (TiO2) phases were investigated to determine the mineralogical risk induced by the natural dispersion of TiO2 minerals. Rock, sediment and surface water samples were collected to determine the physicochemical and mineralogical factors (i.e., size distribution, morphology and alteration) indicative of potential TiO2 toxicity. X-ray diffraction data suggested that titanium oxides were present as rutile and anatase. Scanning electron microscopy images showed elongated TiO2 morphologies; fibres were found as either isolated or embedded/enclosed in flake-like phyllosilicates. The concentration of fibres in stream water ranged from 1.7 to 4.6 million fibres per litre. The highest fibre amounts in the sediments were in the <8-µm fraction, while single fibres were primarily concentrated in the <2-µm fraction. The results indicate that titanium oxide minerals represent a natural source of environmental risk and that the geomineralogical characterization of rich TiO2 areas is indispensable for understanding their geoavailability, dispersion and distribution.

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