scholarly journals Analytical Study for Chlorpyrifos Breakdown Derivatives Qualification After Silver Vanadate (Agvo3) Nanoparticles Fragmentation Reaction

2021 ◽  
Author(s):  
Islam R. Ghoniem ◽  
Ashraf M. Elmarsafy ◽  
Mohamed A. Amer ◽  
Hassan A. El- Gammal ◽  
Mohamed M. Abo Aly ◽  
...  
Keyword(s):  
Environmental Remediation ◽  
Uv Light ◽  
Aquatic Organisms ◽  
Population Increase ◽  
Weather Factors ◽  
Silver Vanadate ◽  
Short Period ◽  
Q Exactive ◽  
High Concentrations ◽  
Cost Of Time

Abstract The use of pesticides in agriculture has become one of the basic necessities to meet the world's food requirements as a result of the continuous population increase. But sometimes the use of some of these pesticides in large quantities and in high concentrations poses a great danger to the environment and then to humans. Through weather factors, pesticides are transferred to the water and then harm aquatic organisms, which leads to a direct impact and harm to the fish wealth. Monitoring these compounds in the environment requires a large cost of time and money to ensure food safety. Therefore, a new method was used in this study in an attempt to get rid of these compounds in water. The silver vanadate nanoparticles (AgVO3) were synthesized using a novel method in an attempt to eliminate different groups of pesticides that had been detected in Egyptian agricultural crops and water. The effect of 0.1 g of AgVO3 nanoparticles were found on three compounds: chlorpyrifos, dimethoate and malathion. Where a concentration of these compounds, which is 0.5 mg / kg, was used and it was estimated using Exion HPLC coupled with Sciex Qtrap API 6500 + LC-MS/MS System. After 15 minutes of treatment with 0.1 g of AgVO3 nanoparticles, these compounds were undetectable on the device's chromatogram, which is regarded a short period in Affecting these compounds and changing their nature in an attempt to get rid of them. Determination of chlorpyrifos breakdown products by using mass scan of Qtrap API 6500 + LC-MS/MS System and Thermo Scientific Q Exactive Focus Orbitrap LC-MS/MS System was investigated. Supported AgVO3 NPs, according to the study, could be used in long-term environmental remediation because they can be used in aqueous solutions at room temperature without the need for additional stimulus such as UV light.

scholarly journals Development of Daphnia magna under exposure to the xenobiotic octylphenol

2014 ◽  
Vol 6 (2) ◽  
pp. 155-158
Author(s):  
Thanh Son Dao ◽  
Thi My Chi Vo ◽  
Hong Lan Chi Do ◽  
Phuoc Dan Nguyen
Keyword(s):  
Developing Country ◽  
Daphnia Magna ◽  
Aquatic Organisms ◽  
Environmental Concerns ◽  
Human Beings ◽  
Ecological Health ◽  
Potential Toxicity ◽  
Chronic Effects ◽  
High Concentrations ◽  
Significant Mortality

Xenobiotics are of human and environmental concerns due to their potential toxicity. Octylphenol is one of the very common and daily used xenobiotics in door and out door activities of human beings. Toxicity of octylphenol to aquatic organisms, especially to zooplankton (e.g. Daphnia magna) was investigated but not fully understood. In this study we evaluated the chronic effects of octylphenol at the concentrations of 5, 50 and 500 µg L-1 on Daphnia magna over a period of 14 days. The results showed that low concentration of octylphenol (5 µg L-1) stimulated the maturation while high concentrations of the chemical (50 and 500 µg L-1) caused a significant mortality to the Daphnia. Besides, all the tested concentrations of octylphenol had serious impacts on fecundity and growth of the animals. Investigations on the presence, distribution, fate and toxicity of xonobiotics including octylphenol in the developing country environment are suggested for human, environmental and ecological health protection. Những hợp chất tổng hợp đang là mối quan ngại cho con người và môi trường vì khả năng gây độc của chúng. Octylphenol là một trong những hợp chất tổng hợp được sử dụng phổ biến và thường xuyên trong những hoạt động của con người trong nhà và ngoài trời. Độc tính của octylphenol đối với thủy sinh vật, đặc biệt đối với động vật phù du (vd. Daphnia magna) mặc dù đã được nghiên cứu nhưng vẫn chưa được hiểu biết đầy đủ. Trong nghiên cứu này, chúng tôi đánh giá ảnh hưởng mãn tính của octylphenol ở các nồng độ 5, 50 và 500 µg/lít lên Daphnia magna trong thời gian 14 ngày. Kết quả cho thấy ở nồng độ octylphenol thấp (5 µg/lít) kích thích sự thành thục của sinh vật trong khi ở nồng độ cao hơn (50 và 500 µg/lít) gây chết đáng kể Daphnia. Bên cạnh đó, tất cả các nồng độ ocytlphenol dùng trong thí nghiệm gây ảnh hưởng nghiêm trọng lên sức sinh sản và sinh trưởng của sinh vật. Nghiên cứu về sự hiện diện, phân bố, phát tán và độc tính của những chất tổng hợp bao gồm octylphenol ở các nước đang phát triển nên được tiến hành vì mục tiêu bảo vệ sức khỏe con người, môi trường và hệ sinh thái.

scholarly journals Photocatalytic activity of Ag/Ni bi-metallic nanoparticles on textile dye removal

2019 ◽  
Vol 8 (1) ◽  
pp. 895-900 ◽  
Author(s):  
Santhanam Mohan ◽  
Manickam Vishnu Devan
Keyword(s):  
Metallic Nanoparticles ◽  
Dye Degradation ◽  
Uv Light ◽  
Wide Band ◽  
Zingiber Officinale ◽  
Band Gap Energy ◽  
Nano Particles ◽  
Textile Dye ◽  
Green Approach ◽  
Short Period

Abstract The photocatalysis of Ag/Ni bi-metallic nano-particles on safranin O dye degradation was evaluated by UV light irradiations. Ag/Ni bi-metallic nanoparticles were synthesized by the green approach using Zingiber officinale root (Zinger) extract. The average particles size of Ag/Ni bi-metallic nanoparticles was found to be 70-88 nm from SEM image and from XRD patterns it was confirmed that the existence of Ag/Ni bi-metallic nano-particles. 8 mg of Ag/Ni bi-metallic nanoparticles present in 40 mL of 10 ppm dye, degraded completely in presence of UV light irradiations within 30 min time durations. The effect of dye degradation within a short period of time (30 min) was due to wide band gap energy and photochemical redox reactions.

scholarly journals Plague and the Regulation of Numbers in Wild Mammals.

1925 ◽  
Vol 24 (2) ◽  
pp. 138-163 ◽  
Author(s):  
C. S. Elton
Keyword(s):  
North America ◽  
Practical Importance ◽  
Sunspot Cycle ◽  
Population Increase ◽  
Eastern Asia ◽  
Climatic Fluctuations ◽  
Short Account ◽  
Wild Mammals ◽  
Short Period ◽  
Rats And Mice

1. A short account is given of the occurrence of plague epidemics in wild mammals other than “domestic” rats and mice. Enough is now known to show that such epidemics are often of great practical importance.2. The method by which most rodents regulate their numbers is as follows: increase in numbers over several years up to a point at which an epidemic of some sort occurs, which kills off a large proportion of the population. Increase then takes place again, and is followed by another epidemic, and so on indefinitely.3. These periodic fluctuations are probably controlled by widespread climatic fluctuations, the best evidence for this being that in certain cases the former run synchronously in widely separated countries.4. There appears to be a dominant short period in fluctuation of three to four years, and a larger movement of period ten to eleven years, both in North America and Europe. The fact that the 11-year sunspot cycle roughly corresponds with the larger movement is significant.5. The data available from Eastern Asia suggest that there too, small mammals fluctuate periodically in numbers, and with similar periods to those of North America and Europe. There is also some evidence that the maxima of the 10–11-year fluctuations coincide in Eastern Asia and in North America, just as those of the 3–4-year period coincide in Northern Canada, Greenland and Norway.6. Evidence is given that the plague marmot (Arctomys bobac), and other rodents carrying plague, are liable to these fluctuations. If this proves to be true, it may be possible, when fuller data are available, to forecast with some accuracy the years of epidemics among these animals, and if this can be done we shall have some means of gauging the likelihood of the occurrence of plague outbreaks in the human population of those regions.7. The available data are admittedly fragmentary, but it is probable that between the years 1931 and 1934 epidemics among A. bobac in Transbaikalia and Mongolia will be severe, and that these events will lead to an increase of plague mortality in man.

scholarly journals Effect of Cadmium and Nickel Exposure on Early Development in Zebrafish (Danio rerio) Embryos

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3005
Author(s):  
Seyed Javid Aldavood ◽  
Louise C. Abbott ◽  
Zachary R. Evans ◽  
Daniel J. Griffin ◽  
MaKenzie D. Lee ◽  
...  
Keyword(s):  
Danio Rerio ◽  
Aquatic Organisms ◽  
Total Body Length ◽  
Hatching Rate ◽  
Spontaneous Movement ◽  
Low Concentrations ◽  
Combined Exposures ◽  
Low Exposure ◽  
High Concentrations ◽  
Danio Rerio Embryos

Exposure to even low concentrations of heavy metals can be toxic to aquatic organisms, especially during embryonic development. Thus, this study aimed to investigate the toxicity of nickel and cadmium in zebrafish (Danio rerio) embryos exposed to environmentally relevant concentrations of each metal alone or in combination from 4 h through to 72 h postfertilization. Neither metal altered survival, but individual and combined exposures decreased hatching rate. Whereas cadmium did not affect total body length, trunk area, eye diameter, or eye area, nickel alone and in combination with cadmium decreased each morphological parameter. Yolk sac area, an index of metabolic rate, was not affected by nickel, but was larger in embryos exposed to high cadmium concentrations or nickel and cadmium combined at high concentrations. Nickel decreased spontaneous movement, whereas cadmium alone or nickel and cadmium combined had no effect. Neither metal altered elicited movement, but nickel and cadmium combined decreased elicited movement. Myosin protein expression in skeletal muscle was not altered by cadmium exposure. However, exposure to nickel at low concentrations and combined exposure to nickel and cadmium decreased myosin expression. Overall, nickel was more toxic than cadmium. In conclusion, we observed that combined exposures had a greater effect on movement than gross morphology, and no significant additive or synergistic interactions were present. These results imply that nickel and cadmium are toxic to developing embryos, even at very low exposure concentrations, and that these metals act via different mechanisms.

scholarly journals Cytotoxicity and UV Light Absorption in Biopolymeric Membranes from Native Vegetation of Mexico

2020 ◽  
Vol 10 (14) ◽  
pp. 4995
Author(s):  
Mayela Alhelí García de Alva Magos ◽  
Jesús Santa-Olalla Tapia ◽  
Miguel Ángel Ramos López ◽  
Jessica Molina Maturano ◽  
Antonio Ruperto Jiménez Aparicio ◽  
...  
Keyword(s):  
Light Absorption ◽  
Uv Light ◽  
Image Texture ◽  
Native Vegetation ◽  
Aloe Barbadensis ◽  
Image Texture Analysis ◽  
Short Period ◽  
Ft Ir ◽  
Large Fiber

Sustainable processing from native vegetation such as agave, nopal and aloe, is mainly centered on the components of lignin, cellulose, and hemicellulose, defined generally as lignocellulosic. Cytotoxicity of lignocellulosic biopolymer membranes (LBMs) of mucilages of Opuntia ficus-indica, Aloe barbadensis Miller, fructans, and residual Agave tequilana Weber fibers at different concentrations (30, 50 and 70%), was evaluated in contact with human fibroblast cells (ATCC® PCS-201-010), cultured in vitro. Long and short LMBs were formed from the fibrous material. The interaction showed mild cytotoxicity according to ISO 10993-5: 2009. Cytotoxic activity demonstrated in the presence of fibroblasts implied a maximum cytotoxicity of close to 46% and a minimum of 7% in LBMs. UV light absorption results of the large fiber LMBs showed the highest prevention of passage of light, having a protective effect mechanism of delaying the response of hypersensitivity as a result of exposure to UV radiation. The morphology and structure were characterized using SEM, FT-IR, and image texture analysis. According to the LBMs reactivity measured, the feasible uses of these membranes can be suggested as materials for biomedical applications over a short period of time, with feasibility as a support to provide some beneficial solutions.

scholarly journals Rapid Biodegradation of the Organophosphorus Insecticide Chlorpyrifos by Cupriavidus nantongensis X1T

2019 ◽  
Vol 16 (23) ◽  
pp. 4593 ◽  
Author(s):  
Shi ◽  
Fang ◽  
Qin ◽  
Chen ◽  
Wu ◽  
...  
Keyword(s):  
Tricarboxylic Acid Cycle ◽  
Aquatic Organisms ◽  
Organophosphorus Hydrolase ◽  
Organophosphorus Insecticides ◽  
Ph Values ◽  
Qpcr Analysis ◽  
Wide Range ◽  
Degradation Activity ◽  
High Concentrations

Chlorpyrifos was one of the most widely used organophosphorus insecticides and the neurotoxicity and genotoxicity of chlorpyrifos to mammals, aquatic organisms and other non-target organisms have caused much public concern. Cupriavidus nantongensis X1T, a type of strain of the genus Cupriavidus, is capable of efficiently degrading 200 mg/L of chlorpyrifos within 48 h. This is ~100 fold faster than Enterobacter B-14, a well-studied chlorpyrifos-degrading bacterial strain. Strain X1T can tolerate high concentrations (500 mg/L) of chlorpyrifos over a wide range of temperatures (30–42 °C) and pH values (5–9). RT-qPCR analysis showed that the organophosphorus hydrolase (OpdB) in strain X1T was an inducible enzyme, and the crude enzyme isolated in vitro could still maintain 75% degradation activity. Strain X1T can simultaneously degrade chlorpyrifos and its main hydrolysate 3,5,6-trichloro-2-pyridinol. TCP could be further metabolized through stepwise oxidative dechlorination and further opening of the benzene ring to be completely degraded by the tricarboxylic acid cycle. The results provide a potential means for the remediation of chlorpyrifos- contaminated soil and water.

NH4Cl affects the expression of Wnt/β-catenin pathway in hepatocytes

2018 ◽  
Vol 96 (3) ◽  
pp. 281-286
Author(s):  
Lu Bai ◽  
Jingjing Li ◽  
Xiaorui Liu ◽  
Shasha Li ◽  
Fulei Li ◽  
...  
Keyword(s):  
Protein Expression ◽  
Control Group ◽  
Cyclin D ◽  
Chang Liver Cell ◽  
Expression Levels ◽  
Low Concentrations ◽  
Short Period ◽  
Mrna And Protein Expression ◽  
High Concentrations ◽  
Chang Liver

We intended to explore whether NH4Cl influences the viability and regulates the expression of Wnt/β-catenin pathway in hepatocytes. The Chang liver cell line was used and cultured with different concentrations of NH4Cl (2.5, 5, 10, 20, 40, and 50 mmol/L) for 12, 24, and 48 h. The viability of hepatocytes was detected by MTT assay. The mRNA and protein expression level was analyzed with qRT–PCR and Western blotting, respectively. NH4Cl concentration significantly affects the viability of hepatocytes. With the increase of NH4Cl concentration, the viability of hepatocytes was decreased, accordingly. The mRNA and protein expression of Wnt1, β-catenin, and cyclin D was significantly increased after treatment with low concentrations of NH4Cl as compared with the control group, whereas their expression levels were decreased after treatment with high concentrations of NH4Cl. The mRNA and protein expression of Wnt1, β-catenin, and cyclin D was also significantly increased after treatment with NH4Cl for a short period as compared with the control group, whereas their expression levels were decreased after treatment with NH4Cl for a long period. In addition, we found NH4Cl treatment significantly reversed the results after RNA silencing of Wnt1 in hepatocytes. NH4Cl influences the viability of hepatocytes and affects the expression of Wnt/β-catenin pathway in hepatocytes.

Band-Gap Engineering Based on Ti@ZnO Nanocolloids: Tunable Optical Properties

2014 ◽  
Vol 617 ◽  
pp. 161-165
Author(s):  
Chrystelle Neaime ◽  
Fabien Grasset ◽  
Tangi Aubert
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Uv Light ◽  
Sol Gel ◽  
Wide Band ◽  
Colloidal Solutions ◽  
Light Emitters ◽  
Wide Range ◽  
High Concentrations ◽  
Acoustic Wave Devices

One of the largest application areas of sol-gel chemistry is thin-film preparation. Using this approach, we started to synthesize M@ZnO colloidal solutions for the preparation of functional thin films. ZnO is a wide band-gap (3.37 eV) semiconductor with large exciton binding energy. In the bulk or in nanosized form, it could be used in a wide range of applications such as UV light emitters, spin functional devices, gas sensors, transparent electronics or surface acoustic wave devices. Since recently, the preparation of innovative functional M@ZnO materials by doping or functionalizing nanocolloids constitutes a new challenge. Using high concentrations of the different Ti@ZnO nanocolloids, we were able to prepare various functional colloidal solutions with tunable emission and thin films, such as red-luminescent Eu3+@ZnTiO3 or versatile ZnTiON colored nanomaterials.

scholarly journals Assessment of TiO2 photoactivity on the lead removal: kinetic and mechanistic processing

2017 ◽  
Vol 75 (11) ◽  
pp. 2508-2519 ◽  
Author(s):  
Anca Peter ◽  
Anca Mihaly-Cozmuta ◽  
Camelia Nicula ◽  
Leonard Mihaly-Cozmuta
Keyword(s):  
Citric Acid ◽  
Uv Light ◽  
Removal Rate ◽  
Catalyst Particle ◽  
Positive Influence ◽  
Lead Removal ◽  
Starting Solution ◽  
Pseudo Second Order ◽  
High Concentrations ◽  
The Impact

Removal of lead ions from aqueous solutions, in the presence and in absence of commercial TiO2, under UV-light was studied. The influence of catalyst mass, concentration of Pb(II) ions and of citric acid in the starting solution as well as the impact of illumination conditions on the removal rate were also investigated. The results were fitted on the pseudo-first order, pseudo-second order and Elovich kinetic models, Weber-Morris intraparticle and liquid film diffusion models, in order to establish the photoreduction mechanism. The Pb removal rate increased in time by a combined linear-exponential mechanism. The catalyst had a positive influence on the removal rate at the start of the photoreduction. At a low concentration of Pb(II) ions (20 mg/L), the amount of photoreduced Pb(II) ions was proportional to the concentration of the citric acid solution, but at high concentrations (240 mg/L), the correlation was inversely proportional. The rate limiting steps in the removal of lead were both the photoreduction on the TiO2 surface and the diffusion through the film surrounding the catalyst particle. The lead removal was significantly influenced by the mobility and by the concentration of the species in solution.

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