Oxygen and pressure changes measured in situ during flooding in roots of the Grey Mangrove Avicennia marina (Forssk.) Vierh.

AbstractTo assess trace element concentrations (Zn, Cu, Pb, Cr, Cd and Ni) in the mangrove swamps along the Saudi coast of the Arabian Gulf, thirteen samples of surface sediment and leaves of grey mangrove, Avicennia marina were collected and analyzed. The detected trace element contents (μg g-1) in surface sediments were in the following descending order according to their mean values; Cr (49.18) > Zn (48.48) > Cu (43.06) > Pb (26.61) > Ni (22.88) > Cd (3.21). The results showed that the average concentrations of Cd and Pb exceeded their world average concentration of shale. The geo-accumulation, potential ecological risk and toxicity response indices demonstrated that trace elements have posed a considerable ecological risk, especially Cd. The inter-relationships between physico-chemical characters and trace elements suggests that grained particles of mud represent a noteworthy character in the distribution of trace elements compared to organic materials. Moreover, the results revealed that Zn was clearly bioaccumulated in leaf tissues A. marina. Dredging, landfilling, sewage effluents and oil pollution can be the paramount sources of pollution in the area under investigation.

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Accumulation of trace metals in grey mangrove Avicennia marina fine nutritive roots: The role of rhizosphere processes

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2013.11.024 ◽

2014 ◽

Vol 79 (1-2) ◽

pp. 284-292 ◽

Cited By ~ 43

Author(s):

Punarbasu Chaudhuri ◽

Bibhash Nath ◽

Gavin Birch

Keyword(s):

Trace Metals ◽

Avicennia Marina ◽

Grey Mangrove ◽

Rhizosphere Processes

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Using earth-tide induced water pressure changes to measure in situ permeability: A comparison with long-term pumping tests

Water Resources Research ◽

10.1002/2015wr017346 ◽

2016 ◽

Vol 52 (4) ◽

pp. 3113-3126 ◽

Cited By ~ 38

Author(s):

Vincent Allègre ◽

Emily E. Brodsky ◽

Lian Xue ◽

Stephanie M. Nale ◽

Beth L. Parker ◽

...

Keyword(s):

Water Pressure ◽

Earth Tide ◽

Pumping Tests ◽

In Situ Permeability ◽

Pressure Changes

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Evaluation of Binding and Abrasion Properties of Grey Mangrove (Avicennia marina) Leaf Extract Against Escherichia coli K12 DNA

Anti-Infective Agents ◽

10.2174/2211352519666210528155419 ◽

2021 ◽

Vol 19 ◽

Author(s):

Praveen Tudu ◽

Shouvik Mahanty ◽

Sushmitha Sriramulu ◽

Punarbasu Chaudhuri ◽

Surajit Pathak

Keyword(s):

Escherichia Coli ◽

Comet Assay ◽

Ethyl Acetate ◽

Ames Test ◽

Leaf Extract ◽

Antimicrobial Properties ◽

Avicennia Marina ◽

Drug Candidate ◽

Escherichia Coli K12 ◽

Grey Mangrove

Background: Mangroves are globally known for their ecological importance and are found to be extensively used in traditional medicine. Avicennia marina, commonly known as grey mangroves exhibit strong antimicrobial properties and are also considered being a promising drug candidate in neutralizing pathogens. Objective: In our present study, the leaf extract from Avicennia marina was isolated using organic solvents of ascensive polarity to evaluate binding and abrasive properties in Escherichia coli K12 DNA. Methods: Samples of the pulverized leaves were used for sequential extraction using ethyl acetate, chloroform and acetone. The minimum inhibitory concentration of isolates from ethyl acetate, chloroform and acetone were quantified to be 0.125gL-1, 0.0625gL-1 and 0.125gL-1, respectively. These values were further utilized to calculate the binding constant between Escherichia coli DNA and isolates. In addition, mutagenicity of the isolates was assessed using Ames test in which the Escherichia coli K12 (strain AB1157) bacteria was cultured in minimal glucose media supplemented with isolates for assessing their DNA modifying ability. Further, DNA abrasion potential was assessed for all the isolates using Comet assay. Results: Results of Ames test showed that the isolates have DNA modifying ability, whereas the Comet assay demonstrated that isolates do not exhibit DNA degrading potential. Conclusion: In conclusion, the mechanism by which the isolates degrade the bacterial cell must be contrary to its DNA degrading potential. Experiments paved the way for further quantification and examination using bioinformatics tools to find the best drug candidate and to run clinical trials

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Remote effects of pressure changes in arterioles

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1995.268.3.h1379 ◽

1995 ◽

Vol 268 (3) ◽

pp. H1379-H1382 ◽

Cited By ~ 10

Author(s):

R. J. Rivers

Keyword(s):

Cheek Pouch ◽

Pressure Flow ◽

Isolated Segment ◽

Myogenic Responses ◽

Pressure Changes ◽

Remote Response

Blood is distributed to match the demands of the tissue in accordance with the local effectors of pressure, flow, nerves, and metabolites. Influences of these effectors are integrated and communicated to larger vessels to create a coordinated upstream response that allows for the blood required to meet the metabolic demands of the tissue. Each effector's contribution to the communicated response is unknown. In the present study in situ segments of arteriole, within the cheek pouch of the anesthetized hamster, were isolated from the pressure and flow of the surrounding vasculature while maintaining electrotonic continuity. Pressure was transiently increased or decreased (-70 to +120 cmH2O) for 60 s. These pressure changes within the isolated segment caused myogenic responses within the isolated segment as well as changes in diameter at remote arteriolar locations (ranging from -8 to 5 microns) that were outside the isolated segment and insulated from the changes in pressure. The size of the remote response correlated significantly with the change in pressure inside the isolated segment. This demonstrates that the effects of pressure changes in arterioles are communicated to neighboring portions of the vasculature.

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Influences of oxygen impurity contained in nitrogen gas on the reactions of chromium with nitrogen

Journal of Materials Research ◽

10.1557/jmr.2005.0341 ◽

2005 ◽

Vol 20 (10) ◽

pp. 2745-2753 ◽

Cited By ~ 3

Author(s):

Yung-Shou Ho ◽

Fong-Shung Huang ◽

Fu-Hsing Lu

Keyword(s):

Oxygen Partial Pressure ◽

Partial Pressure ◽

Oxygen Impurity ◽

Nitrogen Gas ◽

Available Nitrogen ◽

Increasing Temperature ◽

Pressure Changes ◽

Annealing Experiments ◽

Simultaneous Dissolution

In this research, the influences of the oxygen impurity contained in the commercially available nitrogen gas on the reactions of chromium pellets with nitrogen were investigated in the temperature range 600–1350 °C. A small amount of oxygen competed with the majority N2 to react with chromium in the annealing process. Analyzing the in situ oxygen partial pressure changes during annealing proved that the dissolution of oxygen in Cr and/or resultant CrxN (CrN or Cr2N) was exothermic and the solubility decreased with increasing temperature. It was found that the oxygen partial pressure decreased drastically to about 10−22 atm when specimens were annealed at 600 °C compared to a mere 10−5 atm for a blank test, while its value increased with temperature. The oxidation involved simultaneous dissolution of oxygen in specimens and formation of oxide scale. Moreover, comparing the aforementioned results with those obtained from additional annealing experiments preformed in argon gas showed that the formation of Cr2O3 might stem mainly from oxidation of the resultant nitrides instead of the metallic chromium.

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