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131.
Microbial quality and physical–chemical properties of recreational spas were surveyed to investigate the health aspect of the spas’ water. A total of 195 samples were collected from pools and springs of the spas in five sites from Ardebil Province of Iran. The effects of an independent factor defined as ‘condition’ and its component sub-factors (i.e., sampling point, location, and sampling date) on microbial quality and physical–chemical properties of the spas were studied by applying path analysis. The influence of physical–chemical properties on microbial quality was also considered. The percentage of samples exceeding the ISIRI (Swimming pool water microbiological specifications (vol 9412), Institute of Standards and Industrial Research of Iran, Tehran, 2007) limits for Staphylococcus (spp.) was up to 55.8 in the springs and 87.8 in the pools, 58.1 and 99.2 for HPC, 90.7 and 97.8 for total coliform and fecal coliform, and 9.3 and 34.4 for Pseudomonas aeruginosa, respectively. There were significant differences between the pools and springs for both physical–chemical properties and microbial quality. From the path analysis, sampling point was the most effective sub-factor of ‘condition’ on both the physical–chemical properties and microbial quality. Among the physical–chemical properties, water color had the most enhancing or additive influence on microbial pollution, while EC indicated a reducing or subtractive effect.  相似文献   
132.
A new series of 3-phenoxyazetidin-2-ones (β-lactams) were designed and synthesized for the evaluation as selective cyclooxygenase-2 (COX-2) inhibitors. In this study, the effects of a synthetic of β-lactam-structured COX-2 inhibitor with 4-(4-(methylsulfonyl)phenyl)-3-phenoxy-1-phenylazetidin-2-one on cell viability of cancerous lymphoblast isolated from patients diagnosed with acute lymphocytic leukemia (ALL) and normal lymphocytes collected from healthy donors were investigated. The viability % of cancer lymphoblast and normal lymphocyte treated 4-(4-(methylsulfonyl)phenyl)-3-phenoxy-1-phenylazetidin-2-one were tested with MTT assay. Apoptosis and necrosis were measured by double stains of annexin V and propidium iodide, and caspase-3 as a final mediator in apoptotic death measured by colorimetric assay. Mitochondria were isolated from both cancerous lymphoblast and normal lymphocytes to measure parameters of mitochondrial damage such as reactive oxygen species (ROS) formation, mitochondrial membrane potential decrease, swelling, and cytochrome c release following the administration of azithidine-2-one derivative, 4-(4-(methylsulfonyl)phenyl)-3-phenoxy-1-phenylazetidin-2-one. Our results showed that 4-(4-(methylsulfonyl)phenyl)-3-phenoxy-1-phenylazetidin-2-one inhibited proliferation of cancerous lymphoblast in a concentration-dependent manner by inducing apoptosis but not in normal lymphocytes. Treatment with azithidine-2-one derivative produced a rapid loss of mitochondrial transmembrane potential, stimulation of release of ROS and mitochondrial cytochrome c into cytosol, and subsequent induction of procaspase-9 processing. Data suggest that 4-(4-(methylsulfonyl)phenyl)-3-phenoxy-1-phenylazetidin-2-one-induced ROS production led to mitochondria-mediated death signaling that resulted in apoptosis in cancerous lymphoblast cells. The induction of apoptosis by azithidine-2-one compounds, such as 4-(4-(methylsulfonyl)phenyl)-3-phenoxy-1-phenylazetidin-2-one, may provide a mechanism for its cancer chemopreventive action in acute lymphocytic leukemia cells.  相似文献   
133.
Journal of Material Cycles and Waste Management - Many dumping sites all over the world release leachate into the environment. The primary goal of this study was to convert raw municipal...  相似文献   
134.
Water affordability is determined by the percentage of income households that must allocate to municipal water services, while factoring in essential or basic needs water use. With the rise in water prices reported in most areas of the country along with somewhat stagnant income growth—a combination that suggests ceteris paribus—more of a household's disposable income is being spent on water services. This paper adds to the discussion in three ways. First, given the lack of a consistent definition for “affordability” and the subjective connotation associated with such a term, we develop and compare five different water expenditure ratios, including two different measures of water for essential needs, as well as measures for indoor, efficient, and actual water use. Second, because of the granularity of our data, we illustrate how such “affordability” measures can vary significantly within a water district and thus highlight how using district- or county-level income measures can mask the degree to which affordability is an issue for households living in low-income block groups. Our results indicate that the choice of income measure and type of water service use can influence affordability measures substantially.  相似文献   
135.
The present study inspects the relationships between the carbon dioxide (CO2) emissions, real GDP, renewable and non-renewable energy consumption, as well as the service growth for top ten countries (TTC) in service activities. The empirical modeling used in the study involves the procedures of cointegration and tests of Granger causality to inspect the dynamic interaction between the variables during the period from 1980 to 2018. The results of the present study suggest that the variables are cross-sectionally dependent. In addition, the variables appear to be cointegrated based on several tests. The long-run outcomes revealed an inversed U-shaped form between emissions-GDP proving the validity of the environmental Kuznets curve assumption. The fully modified ordinary least squares and dynamic OLS estimates show that the non-renewable energy and economic growth contribute to the increase of CO2 emissions, while service value-added leads to decrease emissions. Furthermore, the renewable energy coefficient comes through as negative but insignificant for the selected panel. The TTC in service should stimulate the usage of renewable energy in various service events for following the path of sustainable development. Devising the investment plans associated with the use of renewable energies is quite essential for the advancement of the service sector leading to mitigating emissions portion.  相似文献   
136.
Journal of Polymers and the Environment - As a promising biodegradable polymer, cellulose triacetate (CTA) was synthesized and plasticized with ionic liquids to produce flexible biocomposite films...  相似文献   
137.
Environmental Chemistry Letters - Rising health issues of Worldwide pollution by fossil fuel products are Fostering the development of safer materials such as biopolymers in many sectors such as...  相似文献   
138.
Environmental Science and Pollution Research - Water contamination due to release of dye containing effluents is one of the environmental problems of serious concern today. The present study...  相似文献   
139.
Environmental Science and Pollution Research - The analysis and probabilistic health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in cereal products were done by using magnetic...  相似文献   
140.
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