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81.
Several reports have indicated that low level of polychlorinated biphenyl (PCB) exposure can adversely affect a multitude of physiological disorders and diseases in in vitro, in vivo, and as reported in epidemiological studies. This investigation is focused on the possible contribution of two most prevalent PCB congeners in vitro in developing toxicities. We used PCBs 138 and 153 at the human equivalence level as model agents to test their specificity in developing toxicities. We chose a global approach using oligonucleotide microarray technology to investigate modulated gene expression for biological effects, upon exposure of PCBs, followed by Ingenuity Pathway Analysis (IPA), to understand the underlying consequence in developing disease and disorders. We performed in vitro studies with human peripheral blood mononuclear cells (PBMC), where PBMC cells were exposed to respective PCBs for 48 h. Overall, our observation on gene expression indicated that PCB produces a unique signature affecting different pathways, specific for each congener. While analyzing these data through IPA, the prominent and interesting disease and disorders were neurological disease, cancer, cardiovascular disease, respiratory disease, as well as endocrine system disorders, genetic disorders, and reproductive system disease. They showed strong resemblances with in vitro, in vivo, and in the epidemiological studies. A distinct difference was observed in renal and urological diseases, organisimal injury and abnormalities, dental disease, ophthalmic disease, and psychological disorders, which are only revealed by PCB 138 exposure, but not in PCB 153. The present study emphasizes the challenges of global gene expression in vitro and was correlated with the results of exposed human population. The microarray results give a molecular mechanistic insight and functional effects, following PCB exposure. The extent of changes in genes related to several possible mode(s) of action highlights the changes in cellular functions and signaling pathways that play major roles. In addition to understanding the pathways related to mode of action for chemicals, these data could lead to the identification of genomic signatures that could be used for screening of chemicals for their potential to cause disease and developmental disorders.  相似文献   
82.
Mesua ferrea L. seed oil (MFLSO) modified polyurethanes blends with epoxy and melamine formaldehyde (MF) resins have been studied for biodegradation with two techniques, namely microbial degradation (broth culture technique) and natural soil burial degradation. In the former technique, rate of increase in bacterial growth in polymer matrix was monitored for 12 days via a visible spectrophotometer at the wavelength of 600 nm using McFarland turbidity as the standard. The soil burial method was performed using three different soils under ambient conditions over a period of 6 months to correlate with natural degradation. Microorganism attack after the soil burial biodegradation of 180 days was realized by the measurement of loss of weight and mechanical properties. Biodegradation of the films was also evidenced by SEM, TGA and FTIR spectroscopic studies. The loss in intensity of the bands at ca. 1735 cm−1 and ca. 1050 cm−1 for ester linkages indicates biodegradation of the blends through degradation of ester group. Both microbial and soil burial studies showed polyurethane/epoxy blends to be more biodegradable than polyurethane/MF blends. Further almost one step degradation in TG analysis suggests degradation for both the blends to occur by breakage of ester links. The biodegradation of the blends were further confirmed by SEM analyses. The study reveals that the modified MFLSO based polyurethane blends deserve the potential to be applicable as “green binders” for polymer composite and surface coating applications.  相似文献   
83.
This paper reviews current biosolids management options, and identifies incineration as a promising technology. Incineration is attractive both for volume reduction and energy recovery. Reported emissions from the incineration of biosolids were compared to various regulations to identify the challenges and future direction of biosolids incineration research. Most of the gaseous and metal emissions were lower than existing regulations, or could be met by existing technologies. This paper also presents the results of an experimental study to investigate the potential use of biosolids for co-incineration with wood pellets in a conventional wood pellet stove. Pilot scale combustion tests revealed that co-incineration of 10% biosolids with 90% premium grade wood pellets resulted in successful combustion without any significant degradation of efficiency and emissions.  相似文献   
84.
This study was undertaken to evaluate the biosorption potential of a natural, low-cost biosorbent, Rambai leaves (Baccaurea motleyana), to remove trace amounts of Hg(II) from aqueous solutions. It was found that the amount of Hg(II) biosorption by Rambai leaves increased with initial metal ion concentration, contact time, and solution pH but decreased as the amount of biosorbent increased. The maximum biosorption capacity was 121.95 mg/g for an initial concentration range of 5 to 120 ppb. Overall, kinetic studies showed that the Hg(II) biosorption process followed pseudo-second-order kinetics based on pseudo-first-order and intraparticle diffusion models. Isotherm data revealed that the biosorption process followed both Freundlich and Langmuir isotherms. The value of separation factor, R(L), from the Langmuir equation and rate of biosorption, n, from the Freundlich model also indicated favorable adsorption.  相似文献   
85.
Louisiana (LA) ranks fifth in the United States in cancer mortality rate. LA's infamous “cancer alley” is a well evidenced region near the southeast part of the Mississippi river surrounding the petrochemical hub of the state. LA has also experienced a high COVID-19 death rate and incidences compared to other states during the recent pandemic. In this study we analyzed publicly available datasets related to health and socio-economic parameters in LA to determine the factors triggering high incidences and deaths caused by COVID-19. Correlation analysis was performed to find the impact of different parameters on the outcome of COVID-19. Our analysis showed higher COVID-19 incidences in the parishes which are in and around the “cancer alley” with a correlation of r = 0.9. Interestingly, results also indicated a strong correlation (r = 0.9) between the death rates caused by asbestos toxicity to COVID-19 caused death rate. Furthermore, we found that office-administration related employment has a positive correlation to COVID-19 incidences in the “cancer alley.” However, we also found both white and black races are equally affected by the COVID-19 pandemic in the “cancer alley” region. In conclusion, our analysis strongly suggests that inhabiting “cancer alley” could significantly enhance the chances of getting affected by SARS-CoV-2 virus compared to other regions in LA.  相似文献   
86.
Environmental Chemistry Letters - In the context of climate change and the circular economy, there is an urgent need to develop biofuels and value-added chemicals from lignocellulosic waste such as...  相似文献   
87.
Abstact The real time monitoring of some organophosphorus based pesticides is of great concern to environmentalists because the widespread use of pesticides is causing severe health hazards to all living beings and also hampering our ecological balance. The traditional methods of measurement of pesticide residues are time consuming, need sample pre-treatment, and lack desired specificity and accuracy. We have developed an amperometric biosensor for indirect measurement of the pesticide concentration precisely in ppb level. The method is based on the action of two enzymes namely acetylcholine esterase and choline oxidase which are uniquely immobilized in a polymeric porous network directly on the working electrode of a screen-printed sensor. Polyacrylamide matrix has been prepared by copolymerisation of acrylamide andN,N′-methylenebisacrylamide using Potassium peroxodisulphate (K2S2O8) as initiator. A linear relationship was obtained between the range of 0 to 10 ppb.  相似文献   
88.
A comprehensive attempt has been made to evaluate the diurnal and spatial pattern of CO2 exchange between the atmosphere and water along the estuarine track of Indian Sundarbans during the two summer months, April and May, 2011. Rigorous field observations were carried out which included the hourly measurements of total alkalinity, pH, fugacity of CO2 in ambient air and water surface, dissolved oxygen, and chlorophyll a. The estuarine water was found rich in total alkalinity and was oversaturated with CO2 throughout the diurnal cycle in the two stations situated at the inner and middle estuary, respectively, whereas an entirely reverse situation was observed in the outer fringes. The fugacity of CO2 in water ranged from 152 to 657 μatm during the study period. The percentage of over-saturation in inner and middle estuary varied from 103 to 168 and 103 to 176 %, respectively, whereas the degree of under-saturation in the outer estuary lied between 40 and 99 %. Chlorophyll a concentrations were found higher in the outer estuary (12.3?±?2.2 mg?m?3) compared to the middle (6.4?±?0.6 mg?m?3) and inner parts (1.6?±?0.2 mg?m?3), followed by a similar decreasing pattern in nutrient availability from the outer to inner estuary. The sampling stations situated at the inner and middle estuary acted as a net source of 29.69 and 23.62 mg?CO2?m?2 day?1, respectively, whereas the outer station behaved as a net sink of ?33.37 mg?CO2 m?2 day?1. The study of primary production and community respiration further supports the heterotrophic nature of the estuary in the inner region while the outer periphery was marked by dominant autotrophic character. These contrasting results are in parity with the source characters of many inner estuaries and sinking characters of the outer estuaries situated at the distal continental shelf areas.  相似文献   
89.
This study focuses on mercury (Hg) bioaccumulation in Indian cat fish, Wallagoo attu and Mystus aor, from different rivers. Methyl mercury (MeHg) concentrations were determined in muscle tissue of two different parts, ventral and dorsal part, of each species and the levels of organic mercury were co-related with lipid content of each part. The MeHg concentrations increased in a linear fashion with both weight and age for these river species. The average concentration of MeHg was found to be 0.93?±?0.60 and 1.26?±?0.62 μg Hg g?1 (expressed in wet weight basis) for ventral and dorsal parts, respectively in W. attu and this was above the 0.25 μg Hg g?1 of wet weight, the limit set by the Prevention of Food Adulteration Act for the maximum level for consumption of fish exposed to mercury pollution. In M. Aor the concentration of MeHg was not above the standard limit but threatening, it was 0.22?±?0.07 and 0.23?±?0.08 μg Hg g?1 (expressed in wet weight basis) in dorsal and ventral parts, respectively.  相似文献   
90.
Michigan water quality standards for public bathing beaches require local health departments to collect and analyze a minimum of three water samples for Escherichia coli during each sampling event. The geometric mean number of E. coli colonies is then compared to the 300 colonies per 100 ml standard to determine compliance. This article compares the results of the currently mandated procedure to a composite sampling method, whereby the three samples are mixed in equal volumes and analyzed once. This effectively replaces the geometric mean of the individual sample results with an arithmetic mean. Although arithmetic means are more affected by outliers, this sensitivity to high concentrations is more health conservative than the geometric mean. During the 2007 sampling season, nine bathing beaches were monitored once each week. Three individual point samples and a composite sample were analyzed for each sampling event. No statistically significant differences in bacteria concentrations were found between composite sample analysis and the arithmetic mean of individual point sample analyses. No violations were detected in the 2007 sampling season, so using historical data, a retrospective analysis was performed on samples gathered at nine bathing beaches in Kalamazoo County, Michigan during the years 2001–2007. The arithmetic mean of the three samples taken at each site served as a surrogate composite sample. The benefits of compositing the three samples were investigated assuming a 2/3 reduction in analytical costs. In the traditional sampling method, three individual samples were obtained and analyzed once in every 3-week period during the summer season, whereas compositing was simulated by taking the arithmetic mean of each week’s results. The results of this retrospective cost analysis indicates that ten to 14 violations would have been missed using the less frequent traditional sampling and analysis methodology. Composite sampling is a cost-saving alternative to traditional sampling techniques that can be more protective of public health, particularly when the savings are applied to increased numbers of samples in time or space.  相似文献   
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