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131.

Human urine (HU) is a biogenic fertilizer which has raised immense interest owing to its capacity of combining sanitation and nutrient recovery. In search of an alternative organic fertilizer for fish culture, the nutrient potential of HU was evaluated. Fries of Indian carps and larvae of freshwater prawn were reared for 120 days under six conditions: (a) aerated and (b) non-aerated fresh HU (0.01%), (c) cattle manure (CM; 1.8 kg tank−1), mixed treatment with CM and HU under (d) iso-phosphorus and (e) iso-nitrogenous condition and (f) control. Monitoring of water quality and biological parameters revealed that total fish yield was the highest in CM (621.5 g tank−1) followed by mixed treatments under iso-nitrogenous (428 g tank−1) and iso-phosphorus (333 g tank−1) conditions, aerated HU (321 g tank−1) and HU (319 g tank−1). The gross primary productivity (GPP) in HU was satisfactory (601.8 mg C m−2 h−1) and superior to all but CM treatment. The abundance of heterotrophic bacteria (HB) was highest in CM and lowest in HU. Both GPP and HB population were correlated positively with fish yield per tank. Although pH in all treatments remained high (pH 8.4–8.9), no ammonia toxicity was observed. No E. coli infestation in any fish muscle was encountered. The concentrations of cadmium and lead in fish muscle were within respective safe level. The study established that high fertilizer potential of HU could be exploited as an alternative organic fertilizer or as a candidate to be blended with cattle manure.

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132.
Process industries have made quite a bit of progress in process safety since the tragic night of December 2, 1984 in Bhopal. Nonetheless, incidents continue to occur on a regular basis due to insufficient understanding of the urgency to identify best practices and drive for process safety improvements in the organization. This paper addresses some of the critical challenges in implementing effective safety programs: (a) failure to learn from past incidents and to capture those lessons into process design, procedures, training, maintenance, and other programs, (b) insufficient attention to leading indicators, and (c) an increase in complexity of process operations and lack of communication. In the presence of these challenges, there is a great need to develop better solutions by utilizing good science based approaches and best practice studies. Potential research areas include, but are not limited to, incident database analysis, reactive chemicals, inherently safer design, combustible dust explosion, facility siting, and the flammability of fuel mixtures and aerosols. In addition, an example was presented on LNG industry safety to illustrate that science-based research is needed to ensure the safe operation and to avoid or mitigate unintended consequences.  相似文献   
133.
The paper deals with bacterial and fungal populations and other pollutants in the indoors of slums, middle class, and upper class dwellings. Both allergenic and nonallergenic organisms have been observed to be higher in slums than in other dwellings. Further, females were more susceptible to various kinds of allergies than males.  相似文献   
134.
Data from two cross-sectional surveys totaling over 2000 farmers in Pakistan are analyzed with regression techniques to estimate the value productivity of irrigation water and related resources. Returns to irrigation water vary by province, but in general are found to be high relative to estimated costs of obtaining water. Salinity of water supplies is an important productivity depressant. The results will be useful in determining the economic feasibility of various means for augmenting supplies and for improving delivery and application efficiencies.  相似文献   
135.
Switchgrass(Panicum virgatum L.) is a perennial C_4 grass native to North America and successfully adapted to diverse environmental conditions. It offers the potential to reduce soil surface carbon dioxide(CO_2) fluxes and mitigate climate change. However, information on how these CO_2 fluxes respond to changing climate is still lacking. In this study, CO_2 fluxes were monitored continuously from 2011 through 2014 using high frequency measurements from Switchgrass land seeded in 2008 on an experimental site that has been previously used for soybean(Glycine max L.) in South Dakota, USA. DAYCENT, a process-based model, was used to simulate CO_2 fluxes. An improved methodology CPTE[Combining Parameter estimation(PEST) with "Trial and Error" method] was used to calibrate DAYCENT. The calibrated DAYCENT model was used for simulating future CO_2 emissions based on different climate change scenarios. This study showed that:(i) the measured soil CO_2 fluxes from Switchgrass land were higher for 2012 which was a drought year, and these fluxes when simulated using DAYCENT for long-term(2015–2070) provided a pattern of polynomial curve;(ii) the simulated CO_2 fluxes provided different patterns with temperature and precipitation changes in a long-term,(iii) the future CO_2 fluxes from Switchgrass land under different changing climate scenarios were not significantly different, therefore, it can be concluded that Switchgrass grown for longer durations could reduce changes in CO_2 fluxes from soil as a result of temperature and precipitation changes to some extent.  相似文献   
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137.
This study explores the relationship between daylight exposure in urban residential units and the mood/happiness of nonworking female residents (housewives) in Isfahan, Iran. A growing body of evidence points to the physiological and psychological benefits of daylight, yet few studies have focused on the relationship between residential daylight and women's mental health. A cross‐sectional study was conducted using two‐stage random cluster sampling of nonworking female occupants of buildings in four residential districts. Mood/happiness was determined using the Oxford Happiness Inventory and the Fordyce Happiness Inventory. Spearman's rank correlation analysis was used to determine the relationship between the variables. A significant relationship was found between residents’ happiness and the amount of daylight in their residential units (Oxford Inventory, r = 0.68, P < 0.05; Fordyce Inventory, = 0.53, P < 0.05). The findings suggest that features of physical residential environments, such as daylight, may be linked to the happiness of housewives. Persons belonging to various demographic groups who spend the majority of their time indoors (e.g., housewives, children, elderly individuals, and people with disabilities) are most dependent on architecture and environmental design for their well‐being, and therefore, are most affected by design decisions.  相似文献   
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139.
Cesium and mercury are two mono-valent elements which can be found in toxic industrial, medical, and nuclear wastes. Their presence in the environment has deleterious effects on the ecosystem, living organisms including humans. Due to the chemical nature of these metals, bioremediation by conventional methods is more difficult to achieve compared to other metals. In this study, we used three biosorbents (oak powder, gall nut, and bacterial exopolymer) for the bioremediation of Hg and Cs. Bio-polymer was produced in the GMS mineral broth. Synthetic wastes of Hg(NO3)2 and isotope Cs-133 as the single-metal solutions were used. The biorefining process was carried out in glass columns, made of Pyrex, with dimensions 20?×?7/2?cm2 with a V-shaped bottom. The samples were analyzed using atomic absorption. The experimental results showed that eliminated metal percent by oak powder, gall nut, and bacterial exopolymer were, respectively, of 94.8%, 96%, and 13.8% for Hg and 7.8%, 4.4%, and 69.4% for Cs. The tests revealed that Ca++, when used as flocculant, played a key role in both biosorption and bio-precipitation rates. Consequently, it was concluded that the investigated biosorbents could be use as an integrated biosorption system for the refinement of mixed wastes.  相似文献   
140.
Breast cancer is the most common cancer in women. Therefore, there is an urgent need to identify and develop therapeutic strategies against this deadly disease. This study is the first to investigate the cytotoxic and apoptotic effects of Scrophularia oxysepala in MCF-7 human breast cancer cells. Dichloromethane, methanol and n-hexane extracts of Scrophularia oxysepala were examined. The 3-(4,5-dimethylethiazol-2-yl)-2,5-diphenyltetrazolium (MTT) reduction and trypan-blue exclusion assays were performed in MCF-7 cells as well as control cell line MCF10A to analyze the cytotoxic activity of the plant. Furthermore, the apoptosis-inducing action of extracts of the plant was evaluated using cell death detection ELISA, the terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL) assay, Western blotting and real-time polymerase chain reaction (PCR). The results showed that dichloromethane and methanol extracts significantly inhibited cell growth and viability without inducing damage to MCF10A cells. Cell death detection ELISA, morphological changes of cells in TUNEL assay, Western blot detection of poly (ADP-ribose) polymerase (PARP) cleavage and increase in the mRNA expression levels of p-53, caspase-3 and c-myc showed that the induction of apoptosis was the main mechanism of cell death. Our results strongly suggest that this plant may contain potential bioactive compound(s) for the treatment of breast cancer.  相似文献   
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