Effect of photoreactivation on ultraviolet inactivation of Microcystis aeruginosa

2011 ◽  
Vol 63 (6) ◽  
pp. 1224-1229 ◽  
Author(s):  
H. Sakai ◽  
H. Katayama ◽  
K. Oguma ◽  
S. Ohgaki
Keyword(s):  
Microcystis Aeruginosa ◽  
Treatment Efficiency ◽  
Yellow Light ◽  
Uv Treatment ◽  
Dna Damages ◽  
Sunlight Irradiation ◽  
Light Yellow ◽  
Uv Lamp ◽  
Incubation Method ◽  
Test Cultures

Microcystis aeruginosa forms algal bloom in lakes. They produce toxic compounds such as microcystin. Against such algal problems, the effect of UV treatment was examined. In UV treatment, the effect of photoreactivation should be examined. Photoreactivation is a repair mechanism of genomic DNA damage by sunlight irradiation. UV treatment causes DNA damages on target cyanobacteria, however sunlight can repair some of these DNA damages. To examine the effect of photoreactivation, both white and yellow light incubations were employed. White light allows both photoreactivation and photosynthesis, while yellow light prohibits photoreactivation and only allows photosynthesis. Microcystis aeruginosa NIES 98 strain and PCC 7806 strain were used as the test cultures. Those cultures were exposed to low-pressure (LP) or medium-pressure (MP) ultraviolet (UV) lamp, then incubated under white or yellow light. Yellow light incubation method was effective to examine photoreactivation. It was revealed that almost six times UV fluence was required to inactivate 99% of Microcystis aeruginosa, under photoreactivation condition, compared with non-photoreactivation condition. Inhibition of photoreactivation could greatly enhance UV treatment efficiency against Microcystis aeruginosa. One of the practical suggestions is to conduct UV treatment at night, when photoreactivation by sunlight rarely takes place. Highly efficient inactivation was achieved by avoiding photoreactivation.

Part VI Global Approach of State Aid Law—WTO Law and EU Trade Defence Instruments, 1 WTO Subsidy Laws: The International Regulation of State Aid

2016 ◽  
Author(s):  
Kreuschitz Viktor ◽  
Nehl Hanns Peter
Keyword(s):  
World Trade ◽  
Red Light ◽  
Harmful Effect ◽  
Green Light ◽  
State Aid ◽  
Yellow Light ◽  
International Regulation ◽  
Light Yellow ◽  
Actionable Subsidies

This chapter focuses on the concepts of subsidy control under World Trade Organization (WTO), prohibiting certain types of subsidies that might have a harmful effect on economic activity in other WTO members. A major innovation of the Agreement on Subsidies and Countervailing Measures (SCM Agreement) was the classification of subsidies into three categories, often referred to as ‘red light’, ‘yellow light’, and ‘green light’. ‘Red light’ subsidies are prohibited per se, with no need to actually prove any adverse effect. The ‘yellow light’ or ‘actionable subsidies’ are not prohibited, but may be challenged only if they cause ‘adverse effects’. Under the ‘green light’ category, certain selected types of subsidies were non-actionable even if they were specific and caused one of the harms listed in Articles 5 and 6 of the SCM Agreement.

scholarly journals Seed Morphometry of Native Indonesian Orchids in the Genus Dendrobium

Scientifica ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Sucipto Hariyanto ◽  
Intan Ayu Pratiwi ◽  
Edy Setiti Wida Utami
Keyword(s):  
Pole Position ◽  
Yellow Light ◽  
Seed Shape ◽  
Apical Pole ◽  
Light Yellow ◽  
Air Space ◽  
Yellow Orange ◽  
Basal Pole ◽  
Qualitative Characters ◽  
Seed Morphometry

In this study, seeds of 10 species of epiphytic orchids were examined using light and scanning electron microscope. Quantitative and qualitative characters were analyzed. All the presently investigated seeds showed are transparent with visible embryo and remarkable embryo color variations (such as pale yellow, light yellow, shiny yellow to yellow, orange, and white). The species showed two groups in seed shape (fusiform and filiform), prolate and oval-shaped embryo, positioned at the center of the long axis and near apical pole. Embryo in prolate shaped and near apical pole position was only in D. antennatum. Based on our investigation, there are variations in seed and embryo volume as well as percentage air space in different taxa of orchids. The highest air space percentages were found in D. leporinum. According to the ornamentation of testa cells, 3 types of seeds were discovered in this genus. Additionally, the clear variation in the testa ornamentation pattern includes the species of D. leporinum, where the testa cells were in the medial regular rectangles, but in the apical and basal pole they are polygonal and irregularly oriented; the testa cells of D. antennatum are polygonal and irregularly oriented and those of D. purpureum are longitudinally oriented with regular rectangles.

scholarly journals Low- or Medium-pressure UV Lamp Inactivation of Microcystis aeruginosa

2005 ◽  
Vol 3 (1) ◽  
pp. 55-61
Author(s):  
Hiroshi SAKAI ◽  
Kumiko OGUMA ◽  
Hiroyuki KATAYAMA ◽  
Shinichiro OHGAKI
Keyword(s):  
Microcystis Aeruginosa ◽  
Medium Pressure ◽  
Uv Lamp

Nickel Induced Oxidative Stress and the Responses of SOD Isoenzymes in Microcystis aeruginosa FACHB-905

2011 ◽  
Vol 356-360 ◽  
pp. 119-126
Author(s):  
Li Juan Huang ◽  
Xue Xiu Chang ◽  
Cheng Wu
Keyword(s):  
Oxidative Stress ◽  
Microcystis Aeruginosa ◽  
Culture Medium ◽  
Dianchi Lake ◽  
Sod Activity ◽  
Oxygen Stress ◽  
Long Period ◽  
South West ◽  
Unfavorable Condition ◽  
Test Cultures

The laboratory experiment was conducted to investigated the effect of nickel over a concentration gradient of 0.1~1.00 mg/L on biomass ( indicated by absorbance of cell culture at 663nm wavelength ), superoxide anion (O2•ˉ), malondialdehyde (MDA), and superoxide dismutase (SOD) in the cyanobacterium Microcystis aeruginosa FACHB 905 isolated from Dianchi Lake, south west of China . The results showed: (1) M. aeruginosa could live normally in Ni (II)-absence culture medium，but 0.3 mg/L Ni(II) was the fittest concentration for test M. aeruginosa, in which biomass and SOD activity were highest among all test cultures; (2) Ni(II) induced O2•ˉ and MDA in M. aeruginosa cells under the experimental condition, showing that Ni(II) could influence on M. aeruginosa by inducing oxidative stress; (3) Fe-SOD and Mn-SOD were found in M. aeruginosa and both of them were induced by lower Ni(II) but inhibited by higher concentration. The multiformity of SOD isoenzymes enhance the resistance of M. aeruginosa to oxygen stress induced by unfavorable condition, which explained that M. aeruginosa is the preponderant species in badly polluted Dianchi Lake water for long period.

Beta-blockers in patients with advanced cirrhosis: Red light, green light, yellow light…

2017 ◽  
Vol 23 (6) ◽  
pp. 725-726 ◽  
Author(s):  
Thoetchai Bee Peeraphatdit ◽  
Patrick S. Kamath ◽  
Vijay H. Shah
Keyword(s):  
Beta Blockers ◽  
Red Light ◽  
Green Light ◽  
Yellow Light ◽  
Light Yellow ◽  
Advanced Cirrhosis ◽  
Light Green

Inheritance of seed coat color of Ethiopian mustard (Brassica carinata A. Braun)

2010 ◽  
Vol 90 (3) ◽  
pp. 279-281 ◽  
Author(s):  
M Rahman ◽  
M Tahir
Keyword(s):  
Seed Coat ◽  
Coat Color ◽  
Brassica Carinata ◽  
Seed Coat Color ◽  
Yellow Light ◽  
Ethiopian Mustard ◽  
Light Yellow ◽  
Inheritance Model ◽  
Pure Lines ◽  
Color Gene

The inheritance of seed coat color was investigated in Brassica carinata in F1, F2, F3 and backcross progenies of crosses between brown- and yellow-seeded pure lines. Seed coat color in B. carinata was not influenced by xenia effect. Segregation pattern followed a mono-genic incomplete dominance inheritance model The occurrence of yellow/light yellow-brown seed trait in B. carinata may be due to an interaction between brown seed coat color gene and dominant repressor (Rp) genes. Key words: Brassica carinata, inheritance, seed coat color, dominant repressor

scholarly journals Photo-Oxidation of Ammonia to Molecular Nitrogen in Water under UV, Vis and Sunlight Irradiation

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 975
Author(s):  
Francesco Conte ◽  
Veronica Pellegatta ◽  
Antonio Tripodi ◽  
Gianguido Ramis ◽  
Ilenia Rossetti
Keyword(s):  
Molecular Nitrogen ◽  
Critical Issue ◽  
The Other ◽  
Light Sources ◽  
Reaction Conditions ◽  
Sunlight Irradiation ◽  
Natural Sunlight ◽  
Photo Oxidation ◽  
Uv Led ◽  
Uv Lamp

Titanium dioxide-based photocatalysts have been used to perform the photo-oxidation of ammonium/ammonia to molecular nitrogen. Different light sources were employed, i.e., UV, LED visible light and natural sunlight, and their performance was compared in order to understand which setup was the most efficient. It was found that under selected conditions, the LED lamp, in combination with silver-promoted TiO2, was able to push the conversion of ammonium toward 48% after 4 h of reaction time. On the other hand, with a more powerful UV lamp, lower conversion was achieved, ca. 40%. Natural sunlight under the same conditions attained more than 38% conversion, but the fluctuation of the reaction conditions remain a very critical issue for the real exploitation of sunlight in water treatment.

scholarly journals In vitro and in vivo efficacies of artesunate in the treatment of cystic echinococcosis

2019 ◽  
Author(s):  
LM Wen ◽  
GD Lv ◽  
J Zhao ◽  
S Lu ◽  
YH Gong ◽  
...  
Keyword(s):  
Cystic Echinococcosis ◽  
Oxygen Species ◽  
Model Group ◽  
Treatment Efficiency ◽  
Dna Damages ◽  
Transmission Electron ◽  
Tnf Α ◽  
High Doses

Abstract Background: In this study, we aim to investigate the efficiency of artesunate (AS) in treating cystic echinococcosis (CE). Methods: Eosin staining and transmission electron microscope (TEM) were utilized for the evaluation of treatment efficiency. DHR123 method and comet assay were utilized to detect reactive oxygen species (ROS) content and DNA damages. Results: Both in vivo and in vitro experiments showed that AS showed significantly higher anti-parasitic effects on CE compared to albendazole (ABZ), especially under in vitro conditions. AS could elevate the ROS level in the protoscoleces (PSCs), which resulted in obvious DNA damages. AS could significant improve the liver function in infected mice compared with the model group (P < 0.05). Moderate and high doses of AS could decrease the TNF-α content compared with the model group (P < 0.05). The content of H2O2 in hydatid fluid treated by AS showed significant decrease compared with the model group (P < 0.01), while the T-SOD level showed significant elevation compared with model group (P < 0.01). Conclusions: In this study, we confirmed that the effects of AS on PSCs may be related to the DNA damages induced by oxidative stress, which provided solid information for the research and development of drugs for hydatid disease.

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