Visually Definite Responses of Freshwater Organisms as Express Indicators of Water Medium Toxicity

2005 ◽  
Vol 41 (6) ◽  
pp. 85-98
Author(s):  
L. P. Braginskiy ◽  
A. A. Ignatyuk
Keyword(s):  
Water Medium ◽  
Freshwater Organisms ◽  
Medium Toxicity

Lead-Free Metal Halide Perovskite Nanocrystals for Photocatalysis in Water

2019 ◽  
Author(s):  
Subhajit Bhattacharjee ◽  
Sonu Pratap Chaudhary ◽  
Sayan Bhattacharyya
Keyword(s):  
Charge Carrier ◽  
Wide Spectrum ◽  
Real Life ◽  
Metal Halide ◽  
Lead Free ◽  
Water Medium ◽  
Type I ◽  
Type Ii ◽  
Perovskite Layer ◽  
Halide Perovskites

<p>Metal halide perovskites with high absorption coefficient, direct generation of free charge carriers, excellent ambipolar charge carrier transport properties, point-defect tolerance, compositional versatility and solution processability are potentially transforming the photovoltaics and optoelectronics industries. However their limited ambient stability, particularly those of iodide perovskites, obscures their use as photocatalysts especially in aqueous medium. In an unprecedented approach we have exploited the photo-absorption property of the less toxic lead-free Cs<sub>3</sub>Bi<sub>2</sub>X<sub>9 </sub>(X = Br, I) nanocrystals (NCs) to catalyse the degradation of water pollutant organic dye, methylene blue (MB) in presence of visible light at room temperature. After providing a proof-of-concept with bromide perovskites in isopropanol, the perovskites are employed as photocatalysts in water medium by designing perovskite/Ag<sub>2</sub>S and perovskite/TiO<sub>2 </sub>composite systems, with Type I (or quasi Type II) and Type II alignments, respectively. Ag<sub>2</sub>S and TiO<sub>2</sub> coatings decelerate penetration of water into the perovskite layer while facilitating charge carrier extraction. With a minimal NC loading, Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>/Ag<sub>2</sub>S degrades ~90% MB within an hour. Our approach has the potential to unravel the photocatalytic properties of metal halide perovskites for a wide spectrum of real-life applications. </p>

Asymmetric Hydrogenation of Benzalacetone Catalyzed by RuCl2 (TPPTS) 2-(S,S)-DPENDS in Water Medium

2010 ◽  
Vol 31 (3) ◽  
pp. 273-277
Author(s):  
Jinbo WANG ◽  
Ruixiang QIN ◽  
Wei XIONG ◽  
Yun JIA ◽  
Derong LIU ◽  
...  
Keyword(s):  
Asymmetric Hydrogenation ◽  
Water Medium

The Biology of Lakes and Ponds

2017 ◽  
Author(s):  
Christer Brönmark ◽  
Lars-Anders Hansson
Keyword(s):  
Evolutionary Ecology ◽  
Global Climate ◽  
Biodiversity Loss ◽  
Environmental Threats ◽  
Freshwater Organisms ◽  
Abiotic Constraints ◽  
Abiotic And Biotic Factors ◽  
The Individual ◽  
Degraded Ecosystems ◽  
Behavioural Adaptations

The Biology of Lakes and Ponds focuses on the interactions between the abiotic frame, such as turbulence, temperature, pH and nutrients, and the organisms, including interactions with and among organisms at the individual, population and community level. The book fills this niche between traditional limnology and evolutionary ecology by focusing on physiological, morphological and behavioural adaptations among organisms to abiotic and biotic factors and how interactions between biotic processes and abiotic constraints determine the structure and dynamics of lake and pond systems. In addition, the book describes and analyses the causes and consequences of human activities on freshwater organisms and ecosystems and covers longstanding environmental threats, such as eutrophication and acidification, as well as novel threats, such as biodiversity loss, use of everyday chemicals and global climate change. However, also signs of improvement and the possibilities to restore degraded ecosystems are discussed and provide hope for future generations.

Acute toxicity of piggery effluent and veterinary pharmaceutical cocktail on freshwater organisms

2021 ◽  
Vol 193 (5) ◽  
Author(s):  
Angela C. Udebuani ◽  
Omoniyi Pereao ◽  
Michael O. Akharame ◽  
Olalekan S. Fatoki ◽  
Beatrice O. Opeolu
Keyword(s):  
Acute Toxicity ◽  
Freshwater Organisms ◽  
Veterinary Pharmaceutical

scholarly journals Synonymous single nucleotide polymorphism in arsenic (+3) methyltransferase of the Western mosquitofish (Gambusia affinis) and its gene expression among field populations

Ecotoxicology ◽  
2021 ◽  
Author(s):  
Daesik Park ◽  
Catherine R. Propper ◽  
Guangning Wang ◽  
Matthew C. Salanga
Keyword(s):  
Gene Expression ◽  
Sequence Variation ◽  
Allelic Variation ◽  
Arsenic Concentration ◽  
Gambusia Affinis ◽  
Contamination Level ◽  
Water Medium ◽  
Single Nucleotide ◽  
Wide Range ◽  
High Arsenic

AbstractNaturally occurring arsenic is toxic at extremely low concentrations, yet some species persist even in high arsenic environments. We wanted to test if these species show evidence of evolution associated with arsenic exposure. To do this, we compared allelic variation across 872 coding nucleotides of arsenic (+3) methyltransferase (as3mt) and whole fish as3mt gene expression from three field populations of Gambusia affinis, from water sources containing low (1.9 ppb), medium-low (3.3 ppb), and high (15.7 ppb) levels of arsenic. The high arsenic site exceeds the US EPA’s Maximum Contamination Level for drinking water. Medium-low and high populations exhibited homozygosity, and no sequence variation across all animals sampled. Eleven of 24 fish examined (45.8%) in the low arsenic population harbored synonymous single nucleotide polymorphisms (SNPs) in exons 4 and/or 10. SNP presence in the low arsenic population was not associated with differences in as3mt transcript levels compared to fish from the medium-low site, where SNPs were noted; however, as3mt expression in fish from the high arsenic concentration site was significantly lower than the other two sites. Low sequence variation in fish populations from sites with medium-low and high arsenic concentrations suggests greater selective pressure on this allele, while higher variation in the low population suggests a relaxed selection. Our results suggest gene regulation associated with arsenic detoxification may play a more crucial role in influencing responses to arsenic than polymorphic gene sequence. Understanding microevolutionary processes to various contaminants require the evaluation of multiple populations across a wide range of pollution exposures.

Sign in / Sign up

Export Citation Format

Share Document