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51.
Excessive air pollution may adversely affect plant growth and development. The overall objective of this research was to elucidate some microscopic effects of diesel exhaust particles (DEP) on the formation, development, and structure of pollen grains and its proteins in Phaseolus vulgaris L. Bean plants were grown in experimental pots and treated with different concentrations of the water-soluble fraction of DEP. Flowers and young buds were removed, fixed in FAA70 (formalin?:?acetic acid?:?ethanol, 2?:?1?:?17), and subjected to developmental studies. Our results show that DEP cause some abnormalities during pollen development. Pollen grains in normal plants are spherical in equatorial view and triangular in polar view; in DEP-treated plants, they were changed into irregular shapes in equatorial view and asteroidal in polar view. Delay in degeneration of the tapetum layer of the anther, and formation of giant, irregular, and non-fertile pollen grains are other results of DEP treatment. Gel electrophoretic studies revealed that a new protein with a molecular mass of 80?kD was formed in the DEP-treated group. Some pollen proteins may act as allergens, considering the fact that pollen allergy frequency is increased in polluted areas; the possibility arises that DEP could be an effective agent entail formation of detoxifying proteins which, on the other hand, can also act as allergens. 相似文献
52.
Seyed Majid Mousavi Babak Motesharezadeh Hossein Mirseyed Hosseini Hoseinali Alikhani Ali Asghar Zolfaghari 《Environmental geochemistry and health》2018,40(4):1221-1235
Many studies have conducted to determine the best management practice to reduce the mobility and phytoavailability of the trace metals in contaminated soils. In this study, geochemical speciation and phytoavailability of Zn for sunflower were studied after application of nanoparticles (SiO2 and zeolite, with an application rate of 200 mg kg?1) and bacteria [Bacillus safensis FO-036b(T) and Pseudomonas fluorescens p.f.169] to a calcareous heavily contaminated soil. Results showed that the biotic and abiotic treatments significantly reduced the Zn concentration in the aboveground to non-toxicity levels compared to the control treatment, and the nanoparticle treatments were more effective than the bacteria and control treatments. The concentration of CaCl2-extractable Zn in the treated soils was significantly lower than those of the control treatment. The results of sequential extraction showed that the maximum portion of total Zn belonged to the fraction associated with iron and manganese oxides. On the contrary, the minimum percent belonged to the exchangeable and water-soluble Zn (F1). From the environmental point of view, the fraction associated with iron and manganese oxides is less bioavailable than the F1 and carbonated fractions. On the basis of plant growth promotion, simultaneous application of the biotic and abiotic treatments significantly increased the aboveground dry biomass yield and also significantly reduced the CaCl2-extractable form, uptake by aboveground and translocation factor of Zn compared to the control treatment. Therefore, it might be suggested as an efficient strategy to promote the plant growth and reduce the mobile and available forms of toxic metals in calcareous heavily contaminated soils. 相似文献
53.
R.M. Nisbet E.B. Muller A.J. Brooks P. Hosseini 《Environmental Modeling and Assessment》1997,2(1-2):7-12
Even when present at sub‐lethal levels, toxic compounds have an effect on the dynamics of a population, expressed through altered growth and reproduction rates. We explore some of the potential effects of toxicants on populations, using a simple model that considers a generic toxicant and populations of two species, a primary producer, and a consumer living under food‐limited conditions. The toxicant is assumed to affect the consumers only, and it may enter them either directly from the environment or via their food, the latter opening the possibility of biomagnification. The initial response of the consumer to introduction of a toxicant is invariably a decline in its fecundity and density. However, in the longer term, the equilibrium densities of both producer and consumer may increase or decrease, depending on parameter values and ambient toxicant levels. The surprising case of an increased equilibrium in response to the toxicant occurs if, in the absence of toxicant, the consumers held the producers at a very low level, analogous to ‘overfishing’ in fishery studies. If the toxicant enters the consumer via food, multiple, non‐trivial equilibria are possible. The complex, but interpretable, dynamics exhibited by these simple models will be used to guide studies with more realistic models, for whose development this study forms a prelude. 相似文献
54.
Ghoochani Samaneh Hashemi Heshmati Abbas Hosseini Hasan Ali Darroudi Majid 《Environmental science and pollution research international》2022,29(23):34406-34418
Environmental Science and Pollution Research - In this study for the very first time, zinc tetraphenylporphyrin (ZnTPP) was loaded into MIL-101 (Zn[TPP]@MIL-101) to perform an adsorptive and... 相似文献
55.
In this paper we quantify the rate of spread of the newly emerged pathogen Mycoplasma gallisepticum of the House Finch, Carpodacus mexicanus, in its introduced range. We compare and contrast the rapid, yet decelerating, rate of spread of the pathogen with the slower, yet accelerating rate of spread of the introduced host. Comparing the rate of spread of this pathogen to pathogens in terrestrial mammalian hosts, we see that elevation and factors relating to host abundance restrict disease spread, rather than finding any major effects of discrete barriers or anthropogenic movement. We examine the role of seasonality in the rate of spread, finding that the rate and direction of disease spread relates more to seasonality in host movement than to seasonality in disease prevalence. We conclude that asymptomatic carriers are major transmitters of Mycoplasma gallisepticum into novel locations, a finding which may also be true for many other diseases, such as West Nile Virus and avian influenza. 相似文献
56.
Characterization of Alginate Hydrogel Beads Loaded with Thyme and Clove Essential Oils Nanoemulsions
Mostaghimi Mahsa Majdinasab Marjan Hosseini Seyed Mohammad Hashem 《Journal of Polymers and the Environment》2022,30(4):1647-1661
Journal of Polymers and the Environment - The present study aimed to evaluate the characteristics of alginate beads filled with thyme and clove essential oils nanoemulsions (EONs). The droplet size... 相似文献
57.
Hosseini A. Brown J. E. Avila R. Beresford N. A. Oughton D. 《Environmental Modeling and Assessment》2022,27(2):311-326
Environmental Modeling & Assessment - In Europe, the two main nuclear accident response decision support systems in use are ARGOS and JRODOS, both of which make use of the FDMT (Food Chain and... 相似文献
58.
Ghozat Ali Sharafati Ahmad Hosseini Seyed Abbas 《Environmental science and pollution research international》2022,29(24):36115-36132
Environmental Science and Pollution Research - In the present study, the spatiotemporal evaluation of the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) satellite precipitation... 相似文献
59.
Hosseini Beinabaj Seyyed Mahdi Bazargan Alireza Sanei Emad 《Journal of Material Cycles and Waste Management》2023,25(5):2835-2844
Journal of Material Cycles and Waste Management - The hydrolysis of organic waste in anaerobic digestion is slow and time-consuming. Pretreatment of the waste can potentially improve hydrolysis and... 相似文献