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291.
Pesticides are chemicals used in agriculture but are known to produce adverse effects on humans. In this study, blood activities of superoxide dismutase (SOD), catalase (CAT), aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyl transaminase, lactate dehydrogenase (LDH), and levels of malondialdhyde (MDA) were determined in 44 greenhouse workers (24 tomato workers, 20 clove workers) and in tomato (24 samples) and clove (20 samples) products. At the end of this study, blood MDA levels and activities of ALT, AST, and LDH levels in greenhouse workers were significantly increased while SOD and CAT activity levels fell significantly. Pesticide residues were not found in agricultural worker blood. Malathion residues (average 0.8?ppm) were detected in tomatoes (8 samples) in these greenhouses. Data suggest that the health of the greenhouse workers may be adversely affected by pesticides.  相似文献   
292.
Accumulation of metals by aquatic organisms is mostly affected by other biological components in environments. In this study, cadmium (Cd) accumulation in green algae, Cladophora glomerata (L.) Kutz., exposed to 0.1 and 1.0 mg L?1 of Cd for 15 and 30 days was examined in laboratory conditions in the presence of Nile tilapia Oreochromis niloticus (L.). The green algae C. glomerata accumulated Cd concentrations as 690 ± 70 and 3430 ± 470 mg kg?1 on day 15, and 1130 ± 180 and 6830 ± 1540 mg kg?1 on day 30. There were significant increases (p < 0.05) in metal accumulation by green algae as the exposure time and metal concentration increased. The results also indicated that the presence of Nile tilapia in the medium led to a significant Cd accumulation in the green algae compared to control (p < 0.05).  相似文献   
293.
This study examines the possibility of designating and implementing a citywide public space network, constituted of randomly dispersed and not interrelated public spaces and greenways across the city of Mu?la. Although Mu?la is a major coastal province, with worldwide tourism districts, the city centre falls behind other settlements in terms of quality of social life, physical layout, economic investment and tourism revenue. In 2001, the local government commissioned the Department of Landscape Architecture of Ege University to prepare a comprehensive master plan towards achieving a corporate public space network, as well as development strategies to ameliorate the previous failures. The master plan developed a blueprint for the citywide network and addressed each existing or potential public space and greenway as integrated components of the network. The process involved short-, medium- and long-term action from the local government to achieve the physical layout and efficiently implement phases of the network. As a guide for other small or medium urban settlements in Turkey, a model proposal was derived from the study to address formulation, implementation, and management of the network in order to create a sustainable urban development.  相似文献   
294.
The risk associated with a given hazard (natural or technological) generally results from the interaction between the hazard potential and the vulnerability. This paper is centred on the assessment of the vulnerability variable. A quantitative vulnerability assessment and mapping methodology is proposed, with two main specificities: (1) it is hazard- and spatially-centred (respectively, oil spills and coastal areas) and; (2) the spatial segregation level used is the municipality. Due to the geographic context of the Portuguese mainland coast, the proposed methodology was applied in an attempt to illustrate the spatial distribution and the degree of the vulnerability associated to oil spills for mainland Portugal coastal municipalities. A final map is presented together with other informative elements. Analysis and discussion of the results allows for the understanding that: (1) there is a very heterogeneous and differential distribution of the degree of vulnerability to oil spills along the Portuguese coastline; (2) the application of specific hazard-centred and spatially-centred vulnerability assessment methodologies, comprising multi-dimensional indicators (e.g., geographic, ecological, demographic, social and economic), produces more robust and realistic results, highlighted by a thorough and spatially detailed analysis; and (3) future research is required on vulnerability assessment in Portugal; along side, hazard potential assessment methodologies must also be developed in order to create a final risk profile, which can be an extremely useful tool in spatial planning and management.  相似文献   
295.
In the framework of a research project entitled ??BRISA??BReaking waves and Induced SAnd transport??, a methodology was devised to characterize the waves joining together in-situ measurements and numerical wave propagation models. With this goal in mind, a number of in-situ measurements were made, for selected positions in front of Praia de Faro (South Portugal), during four days (25th to 28th March, 2009) by using different types of equipments (e.g., resistive wave gauges, pressure sensors, currentmeters and a new prototype pore pressure sensor using optical fibre). Wave records were obtained simultaneously offshore (at a water depth of 11.7?m below mean sea level, MSL) and at the surf and swash zones. The data processing and analysis were made by applying classical time domain techniques. Numerical simulations of the wave propagation between offshore and inshore for the measurement period were performed with two numerical models, a 1D model based on linear theory and a nonlinear Boussinesq-type model, COULWAVE, both forced by the measured offshore wave conditions of 27th March 2009. Comparisons between numerical results and field data for the pressure sensors placed in the surf and swash zones were made and discussed. This approach enables to evaluate the performance of those models to simulate those specific conditions, but also to validate the models by gaining confidence on their use in other conditions.  相似文献   
296.
Portugal is strongly vulnerable to sea hazards due to intense vessel traffic and sea conditions. The southwest region off the Iberian Peninsula lies in the main route from the Mediterranean and Southern Hemisphere to the Northern Europe, causing a ship concentration in a narrow band off Cape S?o Vicente. Tankers represent a significant part of the vessel traffic and the occurrence of oil spills cannot be disregarded. Cape S?o Vicente region is part of a Natural Park with 110 Km of coastline, integrated in the European Natura 2000 network and its socio-economic context is closely related with sea resources exploitation, particularly fishing and tourism. Recognizing the importance of accurate information systems for the decision making process in an oil spill situation, this work presents the development of an integrated tool to support the process in the Algarve coast. The system relies in a regional operational mathematical model based on the MOHID modelling system. The system core is composed by three models (3D hydrodynamics, wave and Lagrangian transport) all linked in the same system and exchanging information in real time. Oil advection and weathering processes are coupled to the Lagragian transport model. The overall operational system includes external operational data products as inputs, to ensure a successful validation of the results. The system is linked to stakeholders and response authorities using a geographic referenced database based on Mapserver technology that will include relevant information for oil spill management.  相似文献   
297.
In this study, indoor and outdoor radon (222Rn) surveys were carried out in the summer and winter seasons in homes of one hundred lung cancer patients in the year 2013–2014. The aim was to investigate the relationship between radon and cancer patients. Lung cancer patients completed a questionnaire concerning their living environment, various physical parameters and living habits. Pearson correlation and t tests revealed no meaningful results between radon concentrations, on one hand, and environmental and personal living habits, on the other hand. Consequently, the BEIR VI model was adapted and 222Rn exposure was estimated to be responsible for about 12% of the lung cancer incidences in the winter season and around 5% in the summer season in the Rize Province. However, due to the limited number of data and numerous parameters that could lead to lung cancer, the estimations done with the model should be taken very lightly. The annual effective doses due to inhalation of indoor and outdoor 222Rn were estimated to be, respectively, 1.43 and 0.94 mSv y?1. The indoor and outdoor annual effective doses were, respectively, close and below the world annual effective dose (1.3 mSv y?1). At the district level, the indoor annual effective dose equivalent in the ?yidere district was 4.52 mSv y?1, which was 3.5 times greater than the world average. The number of patients in the majority of the houses in this district was more than one.  相似文献   
298.
Lagoons are defined as wetlands separated from the sea coasts on which they are located and sit between continental and marine aquatic ecosystems. Çakalburnu Lagoon is a coastal wetland on the southern side of the Bay of ?zmir. Microorganisms, which are quite sensitive to changes occurring in environmental factors, are commonly used to determine the impact of environmental effects on the functioning of the ecosystem. In this study, variations in the abundance and biomass of picoplankton (Synechococcus spp. and bacteria) and the abundance of viruses, which identify the ecological productivity of the food chain, were seasonally examined by epifluorescence microscopy. Moreover, the microbial abundance and biomass relation over time between the physical and chemical parameters was evaluated. According to our results, the maximum abundance of Synechococcus spp. and viruses was 6.7?×?104 cell/ml and 9.9?×?108?cell/ml in the summer, respectively. Otherwise, the highest level of bacteria was measured at 3.6?×?107 cell/ml in the spring. Based on the principal component analysis and Pearson correlation analysis results, we concluded that total suspended solids, Chl-a, particulate organic carbon and particulate organic nitrogen were the major parameters influencing the observed variability of the lagoon system. Overall, to protect and improve the ecological and microbiological quality of aquatic systems such as lagoons, the necessary monitoring and measurement studies should be conducted in these sensitive areas.  相似文献   
299.
Lake Van is the largest lake in Turkey. The lake limits lifespan due to its high pH and brackish water. For this reason, only a single species of fish (Van Fish) is living in the lake that has been adapted to these conditions. In the present study, we investigated the total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA) level and DNA damage effect of bisphenol A (BPA) (10?7, 10?6 and 10?5?M) on primary gill cell culture of Van Fish for 24 and 48?h of incubation periods. TAS levels were not changed when compared to those of the control group, but TOS levels were decreased in both 24 and 48?h. The MDA level increased only at the highest concentration (10?5) at the end of 12 and 24?h (p?.05). DNA damage increased only at the 10?5?M concentration after 48?h. At the end of the experiment, BPA exposure caused lipid peroxidation and genotoxic effect. These results indicate that high levels of BPA exposure induced oxidative stress and DNA damage by time- and concentration-dependent fashion in the gill cell culture of Van Fish. Gill cell culture is a useful model for the rapid identification of the harmful effects of chemicals in the aquatic environment.  相似文献   
300.
Arsenic is a toxic metalloid of global concern. It usually originates geogenically but can be intensified by human activities such as applications of pesticides and wood preservatives, mining and smelting operations, and coal combustion. Arsenic-contaminated food is a widespread problem worldwide. Data derived from population-based studies, clinical case series, and case reports relating to ingestion of inorganic arsenic in drinking water, medications, or contaminated food or beverages show the capacity of arsenate and arsenite to adversely affect multiple organ systems. Chronic arsenic poisoning can cause serious health effects including cancers, melanosis (hyperpigmentation or dark spots, and hypopigmentation or white spots), hyperkeratosis (hardened skin), restrictive lung disease, peripheral vascular disease (blackfoot disease), gangrene, diabetes mellitus, hypertension, and ischemic heart disease.  相似文献   
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