Search results for "Nitrogen"
showing 10 items of 1200 documents
Biostimulant Potential of Humic Acids Extracted From an Amendment Obtained via Combination of Olive Mill Wastewaters (OMW) and a Pre-treated Organic …
2018
Olive mill wastewaters (OMW) detain contain significant levels of phenolic compounds with antimicrobial/phytotoxic activity and high amounts of undecomposed organic matter that may a high pollutant load that exerts negative effects on soil biology because of significant levels in phenolic compounds with antimicrobial/phytotoxic activity and limited biodegradability, and high amounts of undecomposed organic matter. Among OMW detoxification techniques, those focusing on oxidative degradation of phenolic compounds are relevant those focusing on oxidative degradation of phenolic compounds to reduce their toxicity. The composting (bio-oxidation) process in particular, exploits exothermic oxidati…
Osmotic and cryoprotective effects of a mixture of DMSO and ethylene glycol on rabbit morulae.
1993
Abstract Comparisons were made of the osmotic and cryoprotective effects on rabbit embryos preserved by vitrification with 2 solutions and by conventional freezing. Embryos obtained from rabbits killed 70 to 72 h after mating were used in the study (n = 948). Initially, toxicity of the 3 cryoprotectants was studied in fresh (unfrozen) embryos (n = 135). Subsequently, embryos placed in ethylene glycol (EG, 40% v/v; n = 88) and ethylene glycol with dimethyl sulfoxide (EG+DMSO, 20% v/v each, respectively; n = 344) were loaded into straws and plunged directly into liquid nitrogen. Embryos placed in 1.5 M DMSO and 20% heat inactivated rabbit serum were subjected to conventional freezing in a pro…
Computational investigations of 18-electron triatomic sulfur–nitrogen anions
2018
MRCI-SD/def2-QZVP and PBE0/def2-QZVP calculations have been employed for the analysis of geometries, stabilities, and bonding of isomers of the 18-electron anions N2S2−, NS2−, and NSO−. Isomers of the isoelectronic neutral molecules SO2, S2O, S3, and O3 are included for comparison. The sulfur-centered acyclic NSN2−, NSS−, and NSO− anions are the most stable isomers of their respective molecular compositions. However, the nitrogen-centered isomers SNS− and SNO− lie close enough in energy to their more stable counterparts to allow their occurrence. The experimental structural information, where available, is in good agreement with the optimized bond parameters. The bonding in all investigate…
Alpha-lipoic acid: molecular mechanisms and therapeutic potential in diabetes.
2015
International audience; Diabetes is a chronic metabolic disease with a high prevalence worldwide. Diabetes and insulin resistance are associated with the development of cardiovascular and nervous diseases. The development of these disorders reflects complex pathological processes in which the oxidative stress caused by reactive oxygen species (ROS) and reactive nitrogen species (RNS) plays a pivotal role. It is widely accepted that diabetes impairs endothelial nitric oxide synthase (eNOS) activity and increases the production of ROS, thus resulting in diminished NO bioavailability and increased oxidative stress. Alpha-lipoic acid (LA) possesses beneficial effects both in the prevention and …
One pot-like regiospecific access to 1-aryl-1H-pyrazol-3(2H)-one derivatives and evaluation of the anticancer activity
2022
A set of variously substituted 1-arylpyrazol-3-one derivatives, including the di-ortho-aryl substituted ones, was synthesized as new potential anticancer compounds. To fulfill this aim, herein a regiospecific synthesis was proposed utilizing a new revisited one pot procedure, starting from commercial anilines and easily accessible 2,5-dimethyl-furan-3-one. In the course of the sequential ordered steps, in some cases, a nitro group displacement by chlorine took place to a minor extent. The in vitro screening against the full panel of ~60 human cancer cell lines (NCI) showed a moderate, but promising selective antiproliferative activity against the UO31 renal tumor cell line, only in compound…
A review of the importance of mineral nitrogen cycling in the plant-soil-microbe system of permafrost-affected soils : changing the paradigm
2022
The paradigm that permafrost-affected soils show restricted mineral nitrogen (N) cycling in favor of organic N compounds is based on the observation that net N mineralization rates in these cold climates are negligible. However, we find here that this perception is wrong. By synthesizing published data on N cycling in the plant-soil-microbe system of permafrost ecosystems we show that gross ammonification and nitrification rates in active layers were of similar magnitude and showed a similar dependence on soil organic carbon (C) and total N concentrations as observed in temperate and tropical systems. Moreover, high protein depolymerization rates and only marginal effects of C:N stoichiomet…
Mycorrhizal symbiosis changes host nitrogen source use
2021
Abstract Purpose The ecological importance of arbuscular mycorrhizal fungi (AMF) in plant acquisition of inorganic and organic sources of nitrogen (N) is not clear. To improve understanding of the plant N nutrition ecology, we tested the effect of intraspecific competition and AMF in plant N source use in growth and N acquisition. Methods Solidago virgaurea was grown in microcosms in a fully factorial experiment under greenhouse conditions. The factors tested were intraspecific competition between seedlings and adult plants (yes, no), N source (NH4, glycine) and AMF (inoculated with Glomus hoi, not inoculated). Results When grown separately, non-mycorrhizal seedling growth was highest when …
Mise en place d’outils et de bio-indicateurs pertinents de la qualité des sols (Chapitre 9)
2017
Mise en place d’outils et de bio-indicateurs pertinents de la qualité des sols (Chapitre 9)
Analysis and modeling of the role of nitrogen competition in weed control
2020
This project challenges the question of reducing herbicide use, considering that a concomitant reduction of nitrogen fertiliser use and a better choice of the sown species/varieties can help to design more sustainable cropping systems. Combining plant ecophysiology, ecology, agronomy and modelling, this project aims at analysing to which extent optimizing nitrogen fertilisation and crop species/cultivar choice can provide new ways to promote biological weed regulation via plant-plant competition, thereby reducing herbicide use. This project will use an original approach consisting in feeding and then using a mechanistic model, FLORSYS, predicting cropweed community assembly as a function of…
Berseem-annual ryegrass intercropping: effect of plant arrangement and seeding ratio on N2 fixation and yield
2005
Various agronomic factors can affect the productivity and the efficiency of legume-grass intercropping systems. This research was carried out in a Mediterranean semi-arid environment (37°30’N; 13°31’E; 178 m a.s.l.) with the aim to study on berseem clover- annual ryegrass mixture (Trifolium alexandrinum L. – Lolium multiflorum Lam subsp. wersterwoldicum) the effects of different plant arrangement (sowing of the two components in alternate rows or in the same row) and seeding ratios (100:0; 75:25; 50:50; 25:75; 0:100) on forage yield, nitrogen content and nitrogen fixation. The experimental design was a split-plot with four replications. The 15N isotope dilution technique was used to estimat…