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61.
62.
Understanding the spatiotemporal relationships between land use/cover changes (LUCC) and groundwater resources is necessary for effective and efficient land use management. In this paper, geographically weighted regression (GWR) and ordinary least squares (OLS) models have been expanded to analyze varying spatial relationships between groundwater quantity changes and LUCC for three periods: 1987–2000, 2000–2010, and 1987–2010 in the Khanmirza Plain of southwestern Iran. For this purpose, TM images were used to generate LUCC (rainfed, irrigated, meadow, and bare lands). Groundwater quantity variables, including groundwater level changes (GLC) and groundwater withdrawal differences (GWD), were gathered from piezometric and agricultural wells data. The analysis of spatial autocorrelation (Moran’s I and local indicators of spatial association ) demonstrated that GWR has a better ability to model spatially varying data with very minimal clustering of residuals. The results R 2 and corrected Akaike’s Information Criterion parameters revealed that the GWR has the lowest similarity in space and time in neighboring situations and it has the high ability to explain more variance in the LUCC as a function of the groundwater quantity changes. All results of the distribution of local R 2 values from GWR confirm our assertion that there is a spatiotemporal relationship between types of land use and each of groundwater quantity variables within the region. According to the t test results from GWR, there are significant differences between the GLC and GWD and the land use types in different places of region in each of the three time series. The GWR results can help decision-makers to make appropriate decisions for future planning.  相似文献   
63.
Total particulate carbon (TPC), which includes both elemental carbon and particulate organic carbon, total suspended particulate matter (TSP) and dissolved organic carbon (DOC) were measured in 53 cloud water samples collected using a passive 'Harp-wire' cloud collector at weekly intervals at a hill-top site in southern Scotland (Dunslair Heights, 602 m above sea level) between December 1990 and April 1992. The concentrations of TPC, TSP and DOC were in the range 0.03-6.9 mg 1(-1) (median 1.05 mg l(-1)), 2.6-51.6 mg l(-1) (median 13.6 mg l(-1)) and 0.-14 mg l(-1) (median 3.6 mg l(-1)), respectively. The concentrations of TPC, TSP and DOC were greatest in winter (December-February), up to 6.9, 42 and 4.6 mg l(-1) respectively in 1990-1991 and up to 6.0, 51 and 14 mg l(-1), respectively, in 1991-1992. Particulate carbon in cloud water samples comprised 1-47% of the TSP. Concentrations of major anions (Cl(-), NO(-)(3), SO(2-)(4)) and pH were measured on the same water samples. Estimates of cloud liquid water content from January to April 1992 were derived from measured wind speeds and volumes of water collected. These estimates suggested that the air contained up to 1.2 microg TPC m(-3), 16 microg TSP m(-3) and 2.3 microg DOC m(-3), which are typical of concentrations to be expected in rural air. There was no correlation between concentrations of DOC in cloud water and either TPC or TSP, indicating that the sources and partitioning of DOC and TPC in the atmosphere are different. The largest concentrations of TPC coincided with the largest concentrations of non-marine sulphate, and although there was a significant linear correlation between the two sets of data, the log-transformed data were not correlated. Concentrations of TPC were significantly correlated with concentrations of other particulate matter (TSP-TPC), suggesting that similar sources and/or partitioning processes were involved in determining concentrations in cloud. Concentrations of DOC in cloud were significantly correlated (p < 0.02) with concentrations of nitrate, suggesting that sources of DOC were related to the emission and chemistry of nitrogen oxides. The very large concentrations of particulate carbon, especially in winter, indicate that carbon-catalysed oxidation of sulphur dioxide by molecular oxygen in cloud water may be a significant pathway when concentrations of hydrogen peroxide are small.  相似文献   
64.
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   
65.
66.
The ability of free and polysulphone immobilized biomass of Arthrobacter sp. to remove Cu2+ ions from aqueous solution was studied in batch and continuous systems. The Langmuir and Freundlich isotherm models were applied to the data. The Langmuir isotherm model was found to fit the sorption data indicating that sorption was monolayer and uptake capacity (Qo) was 175.87 and 158.7 mg/g for free and immobilized biomass respectively at pH 5.0 and 30 °C temperature, which was also confirmed by a high correlation coefficient, a low RMSE and a low Chi-square value. A kinetic study was carried out with pseudo-first-order reaction and pseudo-second-order reaction equations and it was found that the Cu2+ uptake process followed the pseudo-second-order rate expression. The diffusivity of Cu2+ on immobilized beads increased (0.402 × 10−4 to 0.435 × 10−4 cm2/s) with increasing concentration from 50 to 150 mg/L. The maximum percentage Cu2+ removal (89.56%) and uptake (32.64 mg/g) were found at 3.5 mL/min and 20 cm bed height. In addition to this the Bed Depth Service Time (BDST) model was in good agreement with the experimental data with a high correlation coefficient (>0.995). Furthermore, sorption and desorption studies were also carried out which showed that polysulphone immobilized biomass could be reused for up to six sorption–desorption cycles.  相似文献   
67.
68.
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   
69.
This paper presents a case study of land-use/land-cover (LULC) changes from 1975 to 2014 in the central highlands of Ethiopia and traces out its impact on socioeconomic conditions of the local community in the study area. We used four time series Landsat satellite images, that is, Landsat MSS (1975), Landsat Thematic Mapper (1986), Enhanced Thematic Mapper (2000), and Landsat 8 OLI scenes (2014), to investigate the changes in LULC. In addition, individual interviews with 51 randomly selected households, discussions with focus group and key informants, and field observations were also incorporated for the study. The image classification indicated four categories of LULC classes: Natural forest, eucalyptus plantations, cropland/settlements, and grasslands. Between 1975 and 2014, cropland/settlements and eucalyptus plantations considerably increased, whereas grassland cover drastically decreased. According to the results, the area under cropland/settlements and eucalyptus plantations increased by 62 and 335%, respectively, with 74% concomitant decrease in the area of grasslands in the same period. Survey results showed that deterioration of soil fertility (41.2%) followed by shortage of land (35.3%) is the major constraint for crop production for poor farmers in the study area. However, better-off farmers ranked deterioration of soil fertility (64.7%) followed by lack of credit (17.6%) as priority constraints for crop production. Interviews mainly focused on selected women group revealed that the expansion of eucalyptus in the area greatly curbed the burdens of collecting fuel woods from long distances in the past. The availability of too many religious holidays (on average 16 days/month) directly or indirectly contributes to the current seasonal food shortages of the community. Generally, our results show that the community in the study area is beset with a host of social, economic, and institutional challenges. As a result, majority of the farming households are destitute, unable to make a livelihood from their small plot of land and live in absolute poverty. Therefore, in light of these finding, it is imperative that timely interventions by government and other development stakeholders are needed to come to grips with problems of soil fertility, land-use change, and food insecurity in the study area.  相似文献   
70.
Sweet sorghum is adapted to the hot and dry climatic conditions and its tolerance to slat is moderately. It can be used for different products such as food, feed, fiber and fuel. This study was carried out to evaluate the effects, three nitrogen treatments, and three harvesting stages on the aconitic acid, fiber and invert sugar of three sweet sorghum cultivars in the experimental station and the results showed that the effects were significant. Among nitrogen treatments, application of 100 kg ha(-1) urea at planting and 200 kg ha(-1) urea at 4 leaf stage had the highest aconitic acid (0.26%) and invert sugar (3.44%). Among sweet sorghum cultivars, IS2325 and Vespa had the highest aconitic acid (0.26%) and invert sugar (3.86%), respectively Plant harvested at 4 leaf stage had the highest aconitic acid (0.26%) and the highest invert sugar (3.85%). Rio had higher fiber content than Vespa and IS2325 and all cultivars had the highest fiber content before chilling harvesting stage. In general, since high invert sugar and high aconitic acid interfere crystallization of sugar so, it is suggested that to plant Vespa, apply urea 100 kg ha(-1) urea at planting, 100 kg ha' urea at 4 leaf stage and 100 kg ha(-1) urea at booting and harvested before chilling that had lowest aconitic acid and invert sugar. Thereby, it is recommended to plant Vespa, apply urea 100 kg ha(-1) urea at planting, 100 kg ha(-1) urea at 4 leaf stage and 100 kg ha(-1) urea at booting and harvested at 4 leaf stage that had the highest aconitic acid.  相似文献   
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