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101.
The redevelopment of brownfields and the creation of green space in cities are two initiatives that are gaining support in the US, for they are perceived to be important elements for fostering urban revitalization and more sustainable development. Although these initiatives have evolved separately, the two have started to converge as governments, local communities and other stakeholders begin to consider brownfields as potential locations for green space. A barrier to this convergence, however, has been the focus of brownfield efforts on redevelopment that garners direct economic benefits, as well as the lack of information regarding the benefits that brownfield to green space projects can bring about.

This paper examines the utilization and quality of life impacts of three brownfield to green space projects from the perspective of those using them and the affected communities. The perceptions of respondents (combined N = 479) were assessed via three separate surveys, sharing common questions, which obtained written responses at the point of distribution or elicited mailed responses. The results indicate that these projects quickly achieve regular use and that users partake in a vast array of active and passive recreational activities. The projects also contribute in many ways to personal and community quality of life, particularly in terms of enhancing scenic beauty and neighbourhood appeal, improving access to trails, recreation space, and nature, boosting community pride, removing blight, improving physical fitness and raising property values. In all, 90% of those surveyed felt that green space was a good use for brownfields.  相似文献   
102.
In the search for larvicidal compounds against Aedes aegypti L. (Diptera: Culicidae), a collection of monoterpenes were selected and evaluated. R- and S-limonene exhibited the highest larvicidal potency (LC50 = 27 and 30 ppm, respectively), followed by γ-terpinene (LC50 = 56 ppm) and RS-carvone (LC50 = 118 ppm). Structural characteristics which may contribute to the understanding of the larvicidal activity of monoterpenes were empirically identified. The presence of heteroatoms in the basic hydrocarbon structure decreases larvicidal potency. Conjugated and exo double bonds appear to increase larvicidal potency. Replacement of double bonds by more reactive epoxides decreases the larvicidal potency. The presence of hydroxyls in the cyclic structure resulted in decreased potency, probably due to increased polarity indicanting that lipophilicity seems to play an important role in increasing the larvicidal potency in this set of compounds.  相似文献   
103.
Protecting the health of children and the environment is an essential objective for the health policies of any modern society, being also crucial for a sustainable development, according to the World Health Organization. Evaluating the risk of developing childhood asthma is one of the four priority issues identified by the European Commission, according to the European Union Environment and Health Action Plan.Accordingly, this review aimed to update information concerning the effects of exposure to ozone on childhood asthma, thus helping in the development of strategies for further research. Studies have been demonstrating strong associations between the exposure to ozone and asthma. However, the complexity of exposure patterns, the changes in the vulnerability of children at various stages of development, and the practical limitations of research, lead to a still incomplete understanding of the ozone impact on the health of children. Difficulties on the interpretation of epidemiological studies to evaluate chronic effects are mainly due to an absence of studies designed specifically to address this question and to inherent limitations in characterizing exposure. The more rigorous studies provided new evidences for chronic effects of ozone on small airway function and possibly on asthma, but substantial uncertainties remain.  相似文献   
104.
An important population of the critically endangered pearl mussel Margaritifera margaritifera (Linnaeus, 1758) was surveyed at the edge of its southern distribution (River Paiva, Portugal). Although an earlier study suggested that this population had a very low number of individuals (<500), a narrow distribution, and was mainly comprised by old specimens our data contradict these findings. Our assessment estimated a population with probably more than 5,000 individuals distributed across 80 km of the river length. From the 32 sites surveyed, 19 contained M. margaritifera with higher abundances verified in the middle and upper parts of the river (a maximum of 78 ind. per 100 m of river stretch was recorded). The pearl mussels showed a clear preference for areas near the banks, in shallow water, sandier and gravel sediments, and a high degree of riparian vegetation cover. The population structure was skewed with a very high percentage of large (and old) animals but 3.7 % of the individuals collected were juveniles (<60 mm in length); therefore, this population can be considered functional. Environmental characterization indicated that this river is still in excellent or good condition although some areas showed deterioration due to discharge of domestic effluents. The main conservation requirements of M. margaritifera in the River Paiva include maintaining the water quality (and if possible stopping the discharge of domestic effluents), increasing riparian vegetation cover, removing several weirs to increase connectivity, and increasing trout density.  相似文献   
105.
In Brazil, artisanal and small-scale gold mining (ASGM) produces in the range of 6 tonnes of gold (Au) per annum, and employs approximately 200,000 people. Most of this mining activity is in the Amazon region, where miners have been extracting gold for more than 40 years. In the Tapajos River Basin, assessments indicate that around 99% of miners operate without the environmental and mining permits required by law. This is a result of a combination of unrealistic or lack of proper policies and regulations, lack of political will, lack of infra-structure to enforce the existing regulations and lack of incentives to miners to comply with legal requirements.In this article, we analyze a group of 20 laws, decrees and resolutions in Brazil, focusing on how idiosyncrasies in these regulations reveal gaps between policy and reality in ASGM areas. Artisanal miners operate in vast and remote areas and the government lacks the resources (personnel, vehicles, information and materials) to enforce the laws. Our analysis emphasizes the need for creating new government commitments and identifying priority areas where government agents can focus their efforts.There is no single solution for the environmental, health, technical and socio-economic problems associated with ASGM. However, a realistic approach should consider improving the level of education of miners, creating government programs to provide technical assistance in the field, simplifying administrative procedures and ensuring adequate measures for enforcement.  相似文献   
106.
This study aimed to test the susceptibility of Escherichia coli strains isolated from the water, bottom sediments and individuals cultivated in shrimp farm ponds, to antibiotics belonging to different families, namely B-Lactams: Imipenem (IPM; 10 μ g), Ampicillin (AMP; 10 μ g), Cephalothin (CEP; 30 μ g), Cefoxitin (FOX; 30 μ g), Ceftriaxone (CRO; 30 μ g); Tetracycline: Tetracycline (TCY; 30 μ g); Aminoglycosides: Gentamicin (GEN; 10 μ g), Amikacin (AMK; 30 μ g); Chloramphenicol: Chloramphenicol (CHO; 30 μ g); Fluoroquinolones: Ciprofloxacin (CIP; 5 μ g); Nitrofurans: Nitrofurantoin (NIT; 300 μ g); Sulfonamides: Trimethoprim-Sulfamethoxazole (SXT; 30 μ g); Quilononas: Nalidixic Acid (NAL; 30 μ g). In the laboratory, the method of dissemination (Test Kirby-Bauer) was performed in order to fulfill the antibiogram tests. The results showed high indices of resistance to Imipenem, Cephalothin and Ampicillin. Chloramphenicol, Nitrofurantoin, Cefoxitin, Ceftiaxone and Ciprofloxacin have displayed the highest index of sensitive strains. The antibiotic resistance index (ARI) and the multiple resistance index (MAR) varied within the ranges of 0.068–0.077 and 0.15–0.39, respectively. More than 90.5% of strains of Escherichia coli showed a variety of resistance profiles to the tested antibiotics. The high indices of resistance may be a consequence of indiscriminate use of antibiotics, but also the transfer of resistance through mobile genetic elements found in shrimp farms.  相似文献   
107.
We report the application of a solid lanthanum–ceria–zinc catalyst in the catalytic regeneration of diesel particulate filters(DPF) in diesel engines.We synthesized a CeO_2–ZnO–La_2O_3(Ce–Zn–La) mixed oxide by a lactic acid-mediated sol–gel method,which efficiently coated cordierite substrates for soot capture and combustion.We studied the effects of La loading on the physicochemical and catalytic properties of Ce–Zn mixed oxide during lowtemperature soot combustion processes.We characterized the synthesized catalysts by X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),N2 adsorption,Raman spectroscopy,oxygen storage capacity(OSC),and scanning and transmission electron microscopy(SEM and TEM).Thermogravimetric and differential thermal analysis(TGA/DTA)confirmed that the catalysts effectively reduced the soot oxidation temperature.The ternary Ce–Zn–La mixed oxide catalyst with Ce/Zn/La atomic ratio of 2:1:0.5 had the highest catalytic activity and promoted soot oxidation at temperatures below 390°C.This indicated that the large number of oxygen vacancies in the catalyst structure generated oxygen species at low temperatures.Raman spectroscopy measurements revealed the presence of oxygen vacancies and lattice defects in Ce–Zn–La samples,which were key parameters concerning the stability and redox properties of the prepared catalysts.  相似文献   
108.
Salt marsh plants can sequestrate and inherently tolerate high metal concentrations found in salt marsh sediments. This work intended to understand the Halimione portulacoides (L.) Aellen strategies to prevent metal toxicity, by investigating the metal location in different plant organs and in the cell. A sequential extraction was performed on leaves, stems and roots of H. portulacoides in order to determine and compare the metal (Zn, Pb, Co, Cd, Ni and Cu) concentration in several fractions of the plant material (ethanolic, aqueous, proteic, pectic, polissacaridic, lenhinic and cellulosic). This study shows that all plant organs of H. portulacoides mostly retain metals in the cell wall (65% is the average for all studied metals stored in the root cell wall, 55% in the stems and 53% in the leaves), and the metal content in the intracellular compartment is much lower (21% in roots, 25% in stems and 32% in leaves). High levels of heavy metal in the sedimentary environment do not cause toxicity to H. portulacoides, because H. portulacoides immobilizes them in different cell compartments (cell wall+proteic fraction+intracellular) outside key metabolic sites.  相似文献   
109.
Large dam construction in water deficient areas is a management decision often controversial. Besides providing water storage, economical benefits, and a source of renewable energy, the construction and flooding caused by large dams cause disruptions in natural systems. We monitored the pre- and post-Alqueva dam impacts on the threatened carnivore species (polecat, otter, wildcat and Iberian lynx) populations in SE Portugal, and assessed which factors mostly contribute to post-dam distribution. Major short term impacts of large dams are: (1) increase in accessibility and human presence; (2) movement of heavy machinery and dam-workers; (3) deforestation with habitat loss and fragmentation; (4) change from lotic to lentic system; (5) lower prey availability and harsher capture; and (6) changes in land use adjacent to the reservoir. Thus, the response to those impacts can be predicted as a decline of polecat, wildcat and lynx distribution ranges, and a recovery of the otter from the severe short term impacts. Our results corroborate this hypothesis for all the species, especially during deforestation/early flooding. Otter's distribution range increased in the phase of greater impact, with a subsequent decrease with flooding. Our results suggest carnivores used "escape" areas with favourable habitat and prey conditions, however, the areas with higher probability of species presence decreased by two fold showing a drastic range reduction. To ensure populations' survival of these charismatic threatened carnivore populations of Mediterranean landscapes of south-east Portugal, we propose continuing the monitoring program and the development of a conservation program for the subsisting areas of optimal and suboptimal habitats.  相似文献   
110.
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