Long-term seasonal and temporal changes of hydrogen peroxide from cyanobacterial blooms in fresh waters

2021 ◽  
Vol 298 ◽  
pp. 113515
Author(s):  
Hyojik Yoon ◽  
Hyun-Chul Kim ◽  
Sungpyo Kim
TAPPI Journal ◽  
2016 ◽  
Vol 15 (9) ◽  
pp. 581-586 ◽  
Author(s):  
RICARDO B. SANTOS ◽  
PETER W. HART ◽  
DOUGLAS C. PRYKE ◽  
JOHN VANDERHEIDE

The WestRock mill in Covington, VA, USA, initiated a long term diagnostic and optimization program for all three of its bleaching lines. Benchmarking studies were used to help identify optimization opportunities. Capital expenditures for mixing improvement, filtrate changes, equipment repair, other equipment changes, and species changes were outside the scope of this work. This focus of this paper is the B line, producing southern hardwood pulp in a D(EP)DD sequence at 88% GE brightness. The benchmarking study and optimization work identified the following opportunities for improved performance: nonoptimal addition of caustic and hydrogen peroxide to the (EP) stage, carryover of D0 filtrate to the (EP) stage, and carryover of (EP) filtrate to the D1 stage. As a result of actions the mill undertook to address these opportunities, D0 kappa factor decreased about 5%, sodium hydroxide consumption in the (EP) stage decreased about 35%, chlorine dioxide consumption in the D1 stage decreased about 25%, and overall bleaching cost decreased about 15%.


2020 ◽  
Author(s):  
Erin Alexander ◽  
◽  
Katelyn Weeks ◽  
Randall Debes ◽  
Lindsey Howe ◽  
...  

2014 ◽  
Vol 11 (11) ◽  
pp. 1010-1017 ◽  
Author(s):  
Seoul Hee Nam ◽  
Hyun Wook Lee ◽  
Jin Woo Hong ◽  
Hae June Lee ◽  
Gyoo Cheon Kim

2005 ◽  
Vol 18 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Fernando De Benedetto ◽  
Antonio Aceto ◽  
Beatrice Dragani ◽  
Antonella Spacone ◽  
Stefano Formisano ◽  
...  
Keyword(s):  

Geoderma ◽  
2000 ◽  
Vol 94 (1) ◽  
pp. 43-58 ◽  
Author(s):  
T Chevallier ◽  
M Voltz ◽  
E Blanchart ◽  
J.L Chotte ◽  
V Eschenbrenner ◽  
...  

2021 ◽  
Vol 9 (7) ◽  
pp. 1495
Author(s):  
Tim Piel ◽  
Giovanni Sandrini ◽  
Gerard Muyzer ◽  
Corina P. D. Brussaard ◽  
Pieter C. Slot ◽  
...  

Applying low concentrations of hydrogen peroxide (H2O2) to lakes is an emerging method to mitigate harmful cyanobacterial blooms. While cyanobacteria are very sensitive to H2O2, little is known about the impacts of these H2O2 treatments on other members of the microbial community. In this study, we investigated changes in microbial community composition during two lake treatments with low H2O2 concentrations (target: 2.5 mg L−1) and in two series of controlled lake incubations. The results show that the H2O2 treatments effectively suppressed the dominant cyanobacteria Aphanizomenon klebahnii, Dolichospermum sp. and, to a lesser extent, Planktothrix agardhii. Microbial community analysis revealed that several Proteobacteria (e.g., Alteromonadales, Pseudomonadales, Rhodobacterales) profited from the treatments, whereas some bacterial taxa declined (e.g., Verrucomicrobia). In particular, the taxa known to be resistant to oxidative stress (e.g., Rheinheimera) strongly increased in relative abundance during the first 24 h after H2O2 addition, but subsequently declined again. Alpha and beta diversity showed a temporary decline but recovered within a few days, demonstrating resilience of the microbial community. The predicted functionality of the microbial community revealed a temporary increase of anti-ROS defenses and glycoside hydrolases but otherwise remained stable throughout the treatments. We conclude that the use of low concentrations of H2O2 to suppress cyanobacterial blooms provides a short-term pulse disturbance but is not detrimental to lake microbial communities and their ecosystem functioning.


2000 ◽  
Vol 34 (8) ◽  
pp. 1521-1528 ◽  
Author(s):  
Trevor P. Rodgers-Gray ◽  
Susan Jobling ◽  
Steven Morris ◽  
Carole Kelly ◽  
Sonia Kirby ◽  
...  

1995 ◽  
Vol 108 (5) ◽  
pp. 1977-1990 ◽  
Author(s):  
J.C. Adams

The organisation of the actin cytoskeleton was examined in H9c2 and human intestinal smooth muscle cells adherent on fibronectin or thrombospondin-1. Whereas cells adherent on fibronectin adopted a polygonal shape and rapidly assembled prominent stress fibres and focal contacts, cells adherent on thrombospondin-1 assumed a more irregular morphology with large lamellae containing radial actin microspikes. Focal contacts were not detected in cells adherent on thrombospondin-1, as determined by indirect immunofluorescence staining for vinculin and other focal contact components. Instead, the radial microspikes stained positively for the actin-bundling protein, 55 kDa/fascin, and myosins. In cells adherent on fibronectin, 55 kDa/fascin immunoreactivity was diffuse and tended to be concentrated in the perinuclear region. In long-term adherent cells cultured in serum-containing medium, 55 kDa/fascin was detected in membrane ruffles, in stress fibres and in the perinuclear region. The microspikes formed within 40 minutes of plating cells on thrombospondin-1 and remained present when cells were treated with sodium orthovandate and hydrogen peroxide to increase intracellular phosphotyrosine levels. Indeed, although vanadate-treated cells tended to retract, the microspikes became more prominent and showed an increased intensity of staining for fascin. Under these conditions, a proportion of the microspikes did not appear to be in contact with the substratum: these spikes stained weakly for focal adhesion kinase, talin and vinculin. Cells treated with genistein also spread and formed fascin-containing microspikes which tended to be more slender than those of control cells. In contrast, cells adherent on fibronectin displayed a complex rearrangement of the actin cytoskeleton and a transient enrichment of 55 kDa/fascin-containing structures at the cell surface when treated with sodium orthovanadate and hydrogen peroxide. These observations indicate that cell interactions with fibronectin or thrombospondin-1 send distinct organisational signals to the actin cytoskeleton and may offer a mechanistic framework for further investigations of the anti-adhesive properties of thrombospondin-1.


Sign in / Sign up

Export Citation Format

Share Document