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101.
In India, rain water and atmospheric aerosols are observed to bealkaline in nature due to the influence of soil-derivedparticles which are rich in components like Ca and Mg. Thesecomponents increase the neutralization potential of rain waterand have a greater influence at rural site compared to urbansite. However, if there are continuous rains, the concentrationof crustal components becomes lower resulting in lower pH ofrain water. Unlike the characteristics of rain water oncontinent, the pH of rain water has been observed to be acidicin all the events over the Indian Ocean during Pre-campaigns ofIndian Ocean Experiment (INDOEX). The possible reason for acidicrains over Indian Ocean could be the anthropogenic contributionfrom continent transported by NE winds coming towards the oceanduring this period.  相似文献   
102.
A total of 20 soil samples were collected from mining and non-mining areas of coal field regions of Dhanbad, India. These samples were grown on different types of selective media and a total of 141 isolates, each having plant growth-promoting (PGP) characteristics were obtained. The isolates were further tested for PGP traits (phosphate solubilisation, production of indole acetic acid, hydrogen cyanide, ammonia and siderophores) and a biochemical analysis was done to determine the prevalent species of the region. All the strains selected showed at least two PGP characteristics, which indicated that they can be used as plant growth promoters. Bacillus and Pseudomonas species were prevalent in both mining and non-mining areas, whereas Rhizobium, Azospirillum and Azotobacter were found mostly in the non-mining area. A total of 48 Bacillus, 29 Pseudomonas, 4 Rhizobium, 11 Azospirillum and 10 Azotobacter species were obtained from the two selected regions. The soil samples from the mining region were poor in nutrient content and thus relatively lower numbers of PGP isolates were attained.  相似文献   
103.
The key parameters for designing a horizontal source (horizontal trenches, infiltration ponds, infiltration galleries or blankets) for steady state are the rate liquids can be added to the source, the lateral and vertical extents of the zone of impact of the source, and the liquids volume needed to wet the waste within the zone of impact at steady state. This paper presents charts that a designer can use to estimate these key parameters as functions of source dimensions, injection pressure, and municipal solid waste properties (porosity, hydraulic conductivity, and anisotropy) for designing a new or analyzing an existing horizontal source system for liquids addition to landfilled waste. SEEP/W was used to model liquids flow from a horizontal source in a range of conditions practically encountered for such systems. The governing equation (Richard’s equation) and the boundary conditions were analyzed to formulate dimensionless variables by normalizing the design parameters (flow rate, injection pressure, the lateral zone of impact, injection pressure, and the added liquids volume) with the waste properties and source dimensions. The simulation results were transformed to the respective dimensionless forms and presented in design charts to estimate the key design parameters as functions of the source dimensions, waste properties, and injection pressure. The presentation of the modeling results in the dimensionless form facilitates their use beyond the conditions modeled. A solved example is presented to demonstrate the use of the design charts. The approach presented in the paper should be considered as approximate and designers should use their judgement and experience when using these charts for designing a horizontal liquids addition system for a specific site.  相似文献   
104.
Environmental Science and Pollution Research - Exposures to cadmium and lead can cause oxidative stress, leading to tissue damage resulting in kidney and cardiovascular diseases. The antiaging...  相似文献   
105.
Twin–twin transfusion syndrome (TTTS) is attributed to trans-anastomotic transfusion between twins. Anastomoses are ubiquitous in monochorionic (MC) placentae, yet TTTS develops in only 15%. Although ex vivo and in vivo studies fail to identify a unique anastomotic signature, TTTS placentae are typically associated with an imbalance in unidirectional arteriovenous anastomoses with absent bidirectional anastomoses. Doppler detection of an artery-artery anastomosis reduces the chance of TTTS, whereas, in those that develop the disease, it improves stage-independent survival. Selective laser is often curative, but an increasingly recognized risk of persistent or reverse TTTS may be attributable to atypical arteriovenous anastomoses not identifiable from the chorionic plate. Simple dysvolaemia fails to explain several phenotypic features, including haematological concordancy, recipient hypertension, and reversibly absent end diastolic flow in the donor. The renin-angiotensin system is upregulated in the donor and downregulated in the recipient's kidneys, while paradoxically raised renin levels in the recipient may contribute to raised afterload along with endothelin. Although research is limited in humans by therapy and the lack of a suitable experimental model, further studies of placental and vascular pathophysiology may not only refine current treatment modalities but may also, in addition, suggest further avenues for downstream management such as genetic predisposition testing or pharmacological intervention. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
106.
The nature of work has changed dramatically due to globalisation, migration, technological advances and the emergence of the knowledge-based economy. These changes have been accompanied by the increased prevalence of new and emerging types of risk to workers’ health and safety, such as psychosocial risks. This paper reviews the key regulatory and voluntary standards on occupational health and safety of relevance to the management of psychosocial risks in the workplace that are applicable to the European Union member states. The review indicates that regulatory standards set the minimum level of protection for workers and voluntary standards may further enable organisations to go beyond their legal obligations. However, the review also highlights that the terms ‘stress’ and ‘psychosocial risks’ are not mentioned explicitly in most pieces of legislation leading to lack of clarity on the terminology used. While voluntary standards seek to address this, very few provide specific guidance on the process of psychosocial risk management to enable organisations to manage psychosocial risks successfully. On the basis of the review, the case for the development of a voluntary standard for psychosocial risk management is presented. The paper further discusses the recent development of such a standard and its implications at the European level.  相似文献   
107.
The potential of in-situ monitoring of cytotoxic effects of chromium through root-tip assay was studied in a sugarcane cultivar CoLk 8102 (Saccharum spp. hybrid). Sugarcane setts supplied with graded concentrations of chromium (VI), exhibited a reduction of 85.92 and 95.10 % in mean root length at 40 and 80 ppm Cr dosages along with 61.25 and 82.50% reduction in mean root number/node respectively. Mitotic index of root tip cells of treated setts declined and the frequency of aberrant mitotic phases increased pari passu to the increasing chromium concentration. To compare and quantify the effect of graded chromium dosages on frequency of chromosome aberrations vis-à-vis inhibition of mitotic activity, a 'Decretion factor' (D.F.) has been used for the first time. The value of DF increased with the increase in the chromium dosages. The increase in chromosome aberration frequency was low at low chromium dosages (1 or 2 ppm), but the high Cr dosages (40 and 80 ppm), induced sharp reduction in mitotic efficiency of root system along with anomalies in the process of cell division and induced chromosome aberrations in sugarcane root meristem, which in turn affected the over all plant growth.  相似文献   
108.
Environmental Science and Pollution Research - This study was carried out to investigate how serum cotinine and hydroxycotinine concentrations compare and vary by age, gender, race/ethnicity,...  相似文献   
109.
Environmental Science and Pollution Research - The “environment” has become one of the important and debatable topics of the world and policymakers identifying the new predictors of CO2...  相似文献   
110.
This study models and assesses the significance of risks to health potentially posed to individuals exposed to volatile organic compounds (VOCs) due to being occupationally engaged in cleaning petroleum storage tanks. Exposure processes include hydrocarbon vapor inhalation, ingestion via hand-to-mouth contact, and dermal exposure. Under confined space entry regulations, tank cleaners must wear protective clothing and a breathing apparatus. However, such regulations are recent and sometimes violated. Several factors were found to influence exposure of unprotected individuals cleaning tanks. One factor is climate. This paper reports on a study of tanks in south Texas, which is sunny and hot during most of the year. Solar irradiation of metal surfaces may elevate internal temperatures above ambient air temperatures. Vaporization then elevates airborne hydrocarbon concentrations, and ventilation reduces them, producing a dynamic equilibrium. Human entry, however, disturbs this equilibrium by agitating petroleum residuals. Based upon the above considerations, we have modeled petroleum fuel storage tank dynamics in a case study. We considered three cases: manways closed, manways open, and manways actively ventilated. For CASE I, the concentration of each pollutant in the vapor phase was calculated using Raoult's Law. CASE II and CASE III applied Raoult's Law and also evaluated a mass balance via a mass transfer coefficient derived using the Reynolds Number and the Schmidt Number. Based upon empirical data, the velocity of the air within the tank was assumed to be 1.6 mph. Outputs of the case study included the steady-state concentration of each constituent and time required to reach it. Health risk assessment was conducted to quantify non-cancer risks posed by individual substances (the hazard quotient, HQ) and by simultaneous and/or sequential exposure to multiple substances (the hazard index, HI). During hot months, gross exceedances of acceptability criteria for acute and chronic exposures to mixed solvent vapors occurred. The HI exceeded the acceptability criterion by more than three orders of magnitude. The HI for chronic occupational neurological risks exceeded the acceptability criterion by more than two orders of magnitude. This result is consistent with observed neurological deficits among tank cleaners, such as depression of performance on memory tests among crew members who had worked during hot months. Finally, in such instances, eight-hour time-weighted average mixed-solvent vapor concentrations can exceed half of lethal levels, suggesting that tank cleaners can potentially approach lethal exposure routinely during hot seasons.  相似文献   
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