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Chemical Factors
Published in Michael J. Kennish, Ecology of Estuaries Physical and Chemical Aspects, 2019
Inorganic nitrogen compounds are also transported out of estuaries to the nearshore ocean or released to the atmosphere. Much nitrogen exits some estuaries with the export of organic detritus.10 In general, the nearshore ocean receives more nitrogen from estuaries than it supplies to them. However, vertical and horizontal advection of nutrient-rich deep-ocean water onto continental shelves may dominate nutrient flux processes.216 In Onslow Bay, N.C., for example, Atkinson et al.217 identified upwelled Gulf Stream water as the major source of nitrogen and other nutrients, and river water represented a minor or insignificant source.
General Survey of Geomedicine
Published in Jul Låg, Geomedicine, 2017
Polluted precipitation usually contains nitrogen compounds. The vegetation will often react positively to this addition of matter. However, partial addition of nutrients, as a rule, leads to other necessary elements in the soil being exhausted. Many experiments have shown interesting mutual effects between various nutrients. A large part of the nitrogen compounds in pollution gases are formed during the burning processes.
Inorganic Chemical Pollutants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
The second major pollutants are the nitrous oxides. The most common of these are NO2, N2O, and NO. Many nitrogen compounds are known to harm the chemically sensitive and chronic degenerative disease patients and some may help them, especially NO. A few of the most common that can easily contribute to the total body pollutant load and thus increase chemical sensitivity are discussed in the following pages. Some of these compounds have been seen to induce chemical sensitivity. Most are detoxified by similar detoxification mechanisms; thus, their effects on the chemically sensitive may be cumulative.
How changing environments alter the microbial composition and ecological response in marine biofilms: a mini review
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Marine nitrogen deposition involves the atmospheric input of reactive nitrogen into the marine environment. The process by which reactive nitrogen is transferred from the atmosphere to the ocean affects the pH, nutrient status and biofilm formation of the marine environment. Nitrogen is the most important element that tends to alter primary productivity of marine environment due to its crucial role in marine biogeochemistry and its interrelation with other biogeochemical cycles such as carbon cycle. In marine environment, nitrogen ranges in form from NH4 and NO3 which are in reduce form and fully oxidized form, respectively. This is the reason why nitrogen could act as both electron donor and acceptor in marine environment. The alteration of marine environment caused by GHGE tends to have negative effect on marine biota. It is thereby important to study the role of marine biofilm in marine nitrogen deposition. The marine nitrogen deposition process involves different microbial transformations, and enzymes are found in the organism forming marine biofilm. These processes of transformation of nitrogen compounds in the marine environment tend to have important effects on the stability of nitrogen in marine environment. The present study reports processes involved in marine nitrogen deposition and the role of marine biofilm in the process of nitrogen transformation and deposition. The present study is based on marine-fixed nitrogen, marine-retained nitrogen and marine loss nitrogen.
In silico QSAR modeling to predict the safe use of antibiotics during pregnancy
Published in Drug and Chemical Toxicology, 2023
Feyza Kelleci Çelik, Gül Karaduman
In our study, the aliphatic nitrogen structure appeared as a structural alert. Jiang et al. argue the existence of a double bond adjacent to nitrogen poses a risk of teratogenicity (Jiang et al. 2019). It determined that nitrogen-containing aliphatic, aromatic, or sometimes both, were found in C group molecular structures. Among these structures, which are proved to carry a risk in terms of toxicology, structures carrying two different types of aliphatic nitrogen groups were selected among our descriptive data in the model in which we achieved the highest success. These two significant descriptive data were dCjgOkd_anitrogen__aliphatic_attachb and dNe_aaliphatic_attachb. The descriptors under the Molecular Fragments heading of the Molecular Descriptors Guide are descriptors with nitrogen-containing aliphatic bonds in their structures (https://www.epa.gov/). Many amine groups stimulate respiration, hypertensive response, and heart rate. Aliphatic and aromatic nitrogen compounds were reported as a risky group in carcinogenicity studies, acute toxicity studies, sub-chronic toxicity studies, and chronic toxicity studies, especially in reproductive and developmental toxicity studies (Kennedy and Dabt 2012).
A multidisciplinary approach to the comparison of three contrasting treatments on both lampenflora community and underlying rock surface
Published in Biofouling, 2023
Rosangela Addesso, Daniela Baldantoni, Beatriz Cubero, José Maria De La Rosa, José Antonio González Pérez, Igor Tiago, Ana Teresa Caldeira, Jo De Waele, Ana Z. Miller
A total of 59 different organic compounds were detected from the pyro-chromatograms of the samples and their relative abundances were calculated from the peak areas. The compounds were categorized into 5 main product groups with a similar nature or known origin: Alkyl compounds (ALK); aromatic compounds (ARO), polysaccharide-derived (PS), nitrogen compounds (N), and contaminants (CONT) (Figure 6, Table S2). All the pyro-chromatograms from the vermiculated surfaces were dominated by polysaccharide-derived substances and alkyl structures. Furthermore, no changes in chemical composition were observed after both H2O2 and NaClO treatments. In contrast, clear differences were found for the bare surfaces. Samples treated with H2O2 showed the presence of a series of n-alkane/alkene doublets, which were not present in the control samples. On the contrary, the application of NaClO resulted in the practically total absence of organic molecules, except for the persistence of a few ALK molecules and several small peaks corresponding to ARO compounds. It is remarkable that the NaClO treatment caused the total elimination of PS, which were dominant compounds in all other treatments.