Beneficial effects of dynamic groundwater flow and redox conditions on Natural Attenuation of mono-, poly-, and NSO-heterocyclic hydrocarbons

Natural attenuation of BTEX and characteristics of the water in the study are researched in this paper. The study not only obtain the attenuation rules of BTEX over time, but also the rules of the redox materials of the contaminated groundwater over time. From the study, we reach conclusion that the redox conditions is changed with the increasing pollution of BTEX and the oxidation condition changes into reducing condition. With the changing of the redox condition, there take place a variety of redox reactions. The materials of oxidation, such as O2, NO3-, Fe3+and SO42-, are transformed into reduction materials, such as NO2-, Fe2+, S2- and so on. In this process, the components of BTEX are degradated by micro-organisms which using the oxidation materials as electron acceptors.

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Detailed study of the natural groundwater flow at the natural attenuation forecast test site by well logging

9th EAGE/EEGS Meeting ◽

10.3997/2214-4609.201414623 ◽

2003 ◽

Author(s):

M. Pitrák ◽

M. Kobr

Keyword(s):

Groundwater Flow ◽

Natural Attenuation ◽

Test Site ◽

Well Logging

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Modeling Natural Attenuation of Chlorinated Ethenes Under Spatially Varying Redox Conditions

Biodegradation ◽

10.1023/b:biod.0000044680.39094.cc ◽

2004 ◽

Vol 15 (6) ◽

pp. 435-451 ◽

Cited By ~ 19

Author(s):

Mark A. Widdowson

Keyword(s):

Natural Attenuation ◽

Redox Conditions ◽

Chlorinated Ethenes ◽

Spatially Varying

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Isotopic Fractionation of U in Rocks Reflecting Redox Conditions around a Groundwater Flow Route

MRS Proceedings ◽

10.1557/proc-663-961 ◽

2000 ◽

Vol 663 ◽

Cited By ~ 5

Author(s):

Juhani Suksi ◽

Kari Rasilainen

Keyword(s):

Low Temperature ◽

Groundwater Flow ◽

Isotope Fractionation ◽

Isotopic Fractionation ◽

Redox Conditions ◽

Uranium Series ◽

Chemical Release ◽

Activity Ratios ◽

Selective Chemical

Abstract; Low 234U/238U activity ratios observed in rock and mineral samples were scrutinized. U isotope fractionation leading to 234U depletion (234U/238U<1) in rocks appears to be linked to changes in redox conditions. The fractionation takes place as selective chemical release dominates over direct physical μ recoil. This preferential 234U release depends on the valence contrast between the U isotopes, 238U occurring in +4 form and ingrown 234U, due to oxidizing microenvironment, in +6 form. Observed U isotopic fractionation combined with other uranium series disequilibrium measurements provides a tool for locating redox fronts formed as a result low temperature rock-groundwater interaction.

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Nuclear receptors in disease: the oestrogen receptors

Essays in Biochemistry ◽

10.1042/bse0400157 ◽

2004 ◽

Vol 40 ◽

pp. 157-167 ◽

Cited By ~ 18

Author(s):

Maria Nilsson ◽

Karin Dahlman-Wright ◽

Jan-Åke Gustafsson

Keyword(s):

Nuclear Receptors ◽

Target Genes ◽

Receptor Subtype ◽

Target Tissue ◽

Oestrogen Receptors ◽

Nucleotide Polymorphisms ◽

Cell Type ◽

Single Nucleotide ◽

Beneficial Effects ◽

The Family

For several decades, it has been known that oestrogens are essential for human health. The discovery that there are two oestrogen receptors (ERs), ERalpha and ERbeta, has facilitated our understanding of how the hormone exerts its physiological effects. The ERs belong to the family of ligand-activated nuclear receptors, which act by modulating the expression of target genes. Studies of ER-knockout (ERKO) mice have been instrumental in defining the relevance of a given receptor subtype in a certain tissue. Phenotypes displayed by ERKO mice suggest diseases in which dysfunctional ERs might be involved in aetiology and pathology. Association between single-nucleotide polymorphisms (SNPs) in ER genes and disease have been demonstrated in several cases. Selective ER modulators (SERMs), which are selective with regard to their effects in a certain cell type, already exist. Since oestrogen has effects in many tissues, the goal with a SERM is to provide beneficial effects in one target tissue while avoiding side effects in others. Refined SERMs will, in the future, provide improved therapeutic strategies for existing and novel indications.

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ACE2 as therapeutic agent

Clinical Science ◽

10.1042/cs20200570 ◽

2020 ◽

Vol 134 (19) ◽

pp. 2581-2595

Author(s):

Qiuhong Li ◽

Maria B. Grant ◽

Elaine M. Richards ◽

Mohan K. Raizada

Keyword(s):

Therapeutic Agent ◽

Renin Angiotensin System ◽

Peptide Hormone ◽

Experimental Models ◽

Electrolyte Balance ◽

Ang Ii ◽

Angiotensin Converting Enzyme 2 ◽

Beneficial Effects ◽

Overwhelming Evidence ◽

Future Challenges

Abstract The angiotensin-converting enzyme 2 (ACE2) has emerged as a critical regulator of the renin–angiotensin system (RAS), which plays important roles in cardiovascular homeostasis by regulating vascular tone, fluid and electrolyte balance. ACE2 functions as a carboxymonopeptidase hydrolyzing the cleavage of a single C-terminal residue from Angiotensin-II (Ang-II), the key peptide hormone of RAS, to form Angiotensin-(1-7) (Ang-(1-7)), which binds to the G-protein–coupled Mas receptor and activates signaling pathways that counteract the pathways activated by Ang-II. ACE2 is expressed in a variety of tissues and overwhelming evidence substantiates the beneficial effects of enhancing ACE2/Ang-(1-7)/Mas axis under many pathological conditions in these tissues in experimental models. This review will provide a succinct overview on current strategies to enhance ACE2 as therapeutic agent, and discuss limitations and future challenges. ACE2 also has other functions, such as acting as a co-factor for amino acid transport and being exploited by the severe acute respiratory syndrome coronaviruses (SARS-CoVs) as cellular entry receptor, the implications of these functions in development of ACE2-based therapeutics will also be discussed.

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