Identification of rhizobial strains nodulating Egyptian grain legumes

The presence of apothecia in mixed species (vegetatively reproducing lichens, occasionally producing ascomata) has been interpreted as a mechanism to increase genetic variability in mostly clonal populations. However, spore viability from these apothecia has not been studied. We asked whether ascospores of the mixed species Physconia grisea are viable and thereby contribute to increasing the genetic diversity within populations of this species. An ontogenetic study of spores in cultures of P. grisea and a related sexual species (P. distorta), showed that although mature apothecia from both species produced and discharged meiospores capable of germination, spores from P. grisea were only rarely (0.43 %) able to continue development whereas those from P. distorta germinated and developed successfully. The strongly reduced viability of P. grisea spores suggested that they do not have a strong reproductive function, at least in the two local populations analyzed. Additionally, we show that the segregation of Physconia grisea ssp. lilacina does not have molecular support. [Int Microbiol 2013; 16(3):145-155]Keywords: Physconia spp. · apothecia · sexual reproduction · germination · ontogenetic development · mixed specie

Corrosion inhibition effect of the synthetized 2-butyl-3-({4-[2-(2H-1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1,3-diazaspiro[4.4]non-1-en-4-one drug on CS in 1 M HCl electrolyte: electrochemical, spectroscopic and theoretical investigations

The synthesized IRBESARTAN drug, namely, 2-butyl-3-({4-[2-(2H-1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1,3-diazaspiro[4.4]non-1-en-4-one (IRBESARTAN) was prepared and characterized using NMR spectroscopy. The obtained product was evaluated by electrochemical and spectroscopic measurements as an anticorrosion for carbon steel (CS) in 1.0 M HCl electrolyte. It is obtained that the IRBESARTAN reacts as a good and mixed-type inhibitor, where its performance rises with its concentration and immersion time, which offered inhibition efficiency up to 94.02 % according to EIS measurements. In addition, the temperature influence on the CS dissolution rate was considered without and with IRBESARTAN at the optimum concentration. It is indicated that it is performant at high temperature. Additionally, the thermodynamic and activation data discovered that the IRBESARTAN particles adsorption on the CS area is an endothermic procedure. Indeed, its action obeys to the Langmuir model, relating both physical and chemical actions. The scanning electron microscopy (SEM) analysis demonstrated the construction of a defensive deposit, confirming the electrochemical findings. Finally, the DFT calculations and MD simulation explain the mode of the IRBESARTAN adsorption, and confirm the obtained experimental results

Theoretical and experimental studies of new synthetic quinoxaline derivatives as corrosion inhibitors for mild steel in a 1.0 M HCl environment

The study involved the synthesis and characterization of two hydrazinylidene-based quinoxaline derivatives, namely (2E,3E)-2,3-dihydrazono-6,7-dimethyl-1,2,3,4-tetrahydroquinoxaline (QN-CH3) and (2E,3E)-6-chloro-2,3-dihydrazono-1,2,3,4-tetrahydroquinoxaline (QN-Cl). These derivatives were tested for their effectiveness as inhibitors for mild steel in a 1.0 M hydrochloric acid solution at 363 K using various methods such as electrochemical tests, surface analysis techniques like scanning electron microscopy (SEM), as well as density functional theory (DFT) and molecular dynamics (MD) simulation. It was observed from the current-potential (I-E) curves that both QN-CH3 and QN-Cl acted as cathodic-type inhibitors, with their inhibition efficiencies increasing with concentration. At a concentration of 10-3 M, the inhibition efficiencies reached a maximum of 89.07% for QN-CH3 and 87.64% for QN-Cl. Electrochemical impedance spectroscopy (EIS) tests pointed towards the corrosion process being controlled by charge transfer. The superior performance of QN-CH3 compared to QN-Cl was attributed to the nature of its molecular structure. Furthermore, it was found that the hydrazinylidene-based quinoxaline derivatives adhered to the mild steel surface according to the Langmuir isotherm and maintained their anticorrosion performance at high temperatures, as confirmed by SEM analysis. DFT calculations and MD simulations provided further insight into the corrosion inhibition mechanism

Revealing a brain network endophenotype in families with idiopathic generalised epilepsy

Idiopathic generalised epilepsy (IGE) has a genetic basis. The mechanism of seizure expression is not fully known, but is assumed to involve large-scale brain networks. We hypothesised that abnormal brain network properties would be detected using EEG in patients with IGE, and would be manifest as a familial endophenotype in their unaffected first-degree relatives. We studied 117 participants: 35 patients with IGE, 42 unaffected first-degree relatives, and 40 normal controls, using scalp EEG. Graph theory was used to describe brain network topology in five frequency bands for each subject. Frequency bands were chosen based on a published Spectral Factor Analysis study which demonstrated these bands to be optimally robust and independent. Groups were compared, using Bonferroni correction to account for nonindependent measures and multiple groups. Degree distribution variance was greater in patients and relatives than controls in the 6-9 Hz band (p = 0.0005, p = 0.0009 respectively). Mean degree was greater in patients than healthy controls in the 6-9 Hz band (p = 0.0064). Clustering coefficient was higher in patients and relatives than controls in the 6-9 Hz band (p = 0.0025, p = 0.0013). Characteristic path length did not differ between groups. No differences were found between patients and unaffected relatives. These findings suggest brain network topology differs between patients with IGE and normal controls, and that some of these network measures show similar deviations in patients and in unaffected relatives who do not have epilepsy. This suggests brain network topology may be an inherited endophenotype of IGE, present in unaffected relatives who do not have epilepsy, as well as in affected patients. We propose that abnormal brain network topology may be an endophenotype of IGE, though not in itself sufficient to cause epilepsy

Eco-Friendly Tri-Sodium Citrate as Corrosion Inhibitor for Mild Steel in Synthetic Cooling Water System

The influence of an ecofriendly tri-sodium citrate (TSC) on the inhibition of mild steel corrosion in synthetic cooling water was studied by using potentiodynamic polarization (PP), and electrochemical impedance spectroscopy (EIS) measurements. The state of mild steel surface was characterized by scanning microscopy electron (SEM) analysis. It is found that TSC acts as an anodic type inhibitor where its inhibition increases with concentration to reach a maximum of 89 % at 10-3 M. Indeed, the EIS plots revealed that TSC increases the polarization resistance of mild steel confirming the current-potential measurement and indicated that the inhibition efficiency of TSC increase with immersion time until 24 h of immersion. SEM investigation demonstrated that the inhibition of mild steel in corrosive/TSC solution was realized by the TSC molecules adsorption onto mild steel to prevent the dissolution process by blocking the active sites on its surface. Thus, it is shown that the TSC obey to the Langmuir isotherm and it is adsorbed via both physical and chemical adsorption which can explain by potential of zero charge (PZC) technique

Optical emissions of products sputtered from Fe, Fe

Powder iron has been bombarded by a 5 keV Kr+ ions in a vacuum better than 10-7 torr and under few 10-6 torr ultra pure oxygen partial pressure. The optical spectra of the sputtered particles were recorded between 340.0 nm and 410.0 nm. These spectra exhibit discrete lines, which are attributed to neutral excited atoms of iron. Two iron oxides, namely hematite (Fe2O$_{3})$ and magnetite (Fe3O$_{4})$, in powder form, were studied under the same experimental conditions and identical lines were observed in the obtained spectra. The absolute intensities of the spectral lines in all spectra were measured and the differences in the recorded yield photons were discussed in term of electron-transfer processes between the excited sputtered atom and the bombarded surface. In accordance with the proposed interpretation, we suggest values for the energy gaps and electronic affinities for the studied oxides and for the oxide layer that might be formed by the adsorption of oxygen atoms

Micro-spectrometer for NMR: analysis of small quantities in vitro

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Anthropogenic nitrate contamination impacts nitrous oxide emissions and microbial communities in the Marchica Lagoon (Morocco)

Lagoon systems are often confined, and their waters are poorly renewed, which makes them vulnerable to pollutants’ accumulation. Here, the impact of different sources of anthropogenic contamination (domestic, urban, industrial, and agricultural) on the nitrate (NO) content, emission of the greenhouse gas nitrous oxide (NO), abundance of total bacterial archaeal, nitrifying, and denitrifying communities, and diversity and composition of bacterial communities in the sediments of the RAMSAR-protected Marchica lagoon (Nador, Morocco) was investigated. Six lake sites differing in NO concentration were selected. Wastewater coming from industrial activities results in the greatest concentration of NO in sediments and emissions of NO. Increased carbon to nitrogen content in sites near domestic activities resulted in an increase in the abundance of total bacterial and archaeal communities, as well as nitrification and denitrification genes, but low NO emissions due to a greater presence of microorganisms involved in NO production over those able to reduce NO. Significant differences in bacterial community composition between sites were observed, with the NO content being the main driver of these changes. Increased NO content in the sampling sites significantly reduced bacterial diversity. Bacterial genera involved in the degradation of organic and inorganic pollutants and nitrous oxide reduction, such as Robiginitalea, Symbiobacterium, Bacillus, Fusibacter, Neptunomonas, Colwellia, and Alteromonas, were the most abundant in the lagoon. The results suggest that the type of anthropogenic contamination directly impacts the nitrate content in the sediments of the Marchica lagoon, which determines variations in nitrous oxide emissions, nitrogen-cycling gene abundances, and bacterial diversity

Triptolide reduces cyst formation in a neonatal to adult transition Pkd1 model of ADPKD

Background. Autosomal dominant polycystic kidney disease (ADPKD), a major cause of end-stage renal failure, results from genetic mutation of either polycystin-1 (Pkd1) or polycystin-2 (Pkd2). In order to develop novel therapies to treat the advancement of disease progression, numerous rodent models of different genetic backgrounds are available to study cyst development