Unveiling the non-polar [3+2] cycloaddition reactions of cyclic nitrones with strained alkylidene cyclopropanes within a molecular electron density theory study.

The role of cyclopropane substitution on the ethylene in [3+2] cycloaddition (32CA) reactions of cyclic nitrones has been studied within Molecular Electron Density Theory (MEDT) at the B97X-D/6-311G(d,p) computational level. Electron Localization Function (ELF) analysis of the ethylenes shows that the presence the cyclopropane only slightly increases the electron density in the C-C bonding region. Analysis of the Conceptual DFT reactivity indices indicates that the presence of the cyclopropane does not produce any remarkable change in the reactivity of these strained ethylenes.

Understanding the different reactivity of ()- and ()-β-nitrostyrenes in [3+2] cycloaddition reactions. An MEDT study.

The experimental reactivity of isomeric ()- and ()-β-nitrostyrenes participating in [3+2] cycloaddition (32CA) reactions has been analysed on the basis of molecular electron density theory (MEDT) at the HF/6-311G(d,p), B3LYP/6-311G(d,p) and B97X-D/6-311G(d,p) computational levels. It was found that the polar 32CA reactions with 5,5-dimethylpyrroline--oxide proceed a one-step mechanism, characterised by the attack of the nucleophilic oxygen centre of the nitrone on the electrophilically activated β-position of these nitrostyrenes. This behaviour is completely understood by means of the analysis of the conceptual DFT reactivity indices.

Use of digital displays and ocular surface alterations: A review.

Digital display use has been accepted to be implicated as a contributing factor for dry eye disease (DED). Abnormal blinking during computer operation, including a reduced blink rate and an incomplete eyelid closure, increased palpebral fissure as consequence of high visualization angles, and meibomian gland dysfunction associated to long-term display use, are behind the increased prevalence of dry eye signs and symptoms found in digital display users. Previous research reveals significant reductions in tear volume and stability, alterations in tear film composition, including increased osmolarity, inflammatory cytokines, oxidative stress markers and reduced mucin secretion, eyelid abnormalities and ocular surface damage, encompassing corneal and conjunctival staining and bulbar redness, as a direct consequence of digital display use.

Unraveling the kinetics and molecular mechanism of gas phase pyrolysis of cubane to [8]annulene.

The kinetic and electron density flows are studied theoretically for the gas phase pyrolysis of cubane its cage opening to reach bicyclooctatriene and then thermal rearrangement of bicyclooctatriene to produce [8]annulene which is the experimentally observed major product. The observed kinetic data at the MN15-L/maug-cc-pVTZ level of theory were in good agreement with the experimental results as compared to the CBS-QB3 method. The cage opening and the thermal rearrangement steps at the experimentally employed temperature of 520 K were exergonic and exothermic.

A molecular electron density theory study of the participation of tetrazines in aza-Diels-Alder reactions.

The reactions of eight tetrazines of increased electrophilic character with nucleophilic tetramethyl ethylene (TME) and with electrophilic tetracyanoethylene (TCE) have been studied using Molecular Electron Density Theory. These reactions are domino processes comprising an aza-Diels-Alder (ADA) reaction followed by an extrusion of molecular nitrogen, yielding a dihydropyridazine. Analysis of the conceptual DFT (CDFT) indices showed an increase of the electrophilicity and a decrease of the nucleophilicity of tetrazines with an increase of the electron-withdrawing character of the substituent.

A molecular electron density theory study of the mechanism, chemo- and stereoselectivity of the epoxidation reaction of -carvone with peracetic acid.

The epoxidation reaction of -carvone 8 with peracetic acid 9 has been studied within the molecular electron density theory at the B3LYP/6-311(d,p) computational level. The chemo- and stereoisomeric reaction paths involving the two C-C double bonds of -carvone 8 have been studied. DFT calculations account for the high chemoselectivity involving the C-C double bond of the isopropenyl group and the low diastereoselectivity, in complete agreement with the experimental outcomes.

Electrochemical monitoring of ROS influence on seedlings and germination response to salinity stress of three species of the tribe Inuleae.

Solid-state electrochemical methods have been applied to the establishment of patterns of plant growth and response to saline stress using seedlings of L., (L.) Greuter ( (L.

DFT exploration of [3 + 2] cycloaddition reaction of 1-phosphorinium-3-olate and 1-methylphosphorinium-3-olate with methyl methacrylate.

A Molecular Electron Density Theory (MEDT) study of the regio- and stereoselectivity of the [3 + 2] cycloaddition (32CA) reaction of 1-phosphorinium-3-olate and 1-methylphosphorinium-3-olate with methyl methacrylate was carried out using the B3LYP/6-31G(d) method. In order to test the method dependence for the most favorable reaction path leading to the 1-substituted 6- cycloadduct (CA) various functionals using higher basis sets were taken into consideration in the gas phase. An analysis of the energetic parameters indicates that the reaction path leading to 6- CA are kinetically as well as thermodynamically favored in the gas phase, THF and ethanol.

Comprehensive identification of Vibrio vulnificus genes required for growth in human serum.

Vibrio vulnificus can be a highly invasive pathogen capable of spreading from an infection site to the bloodstream, causing sepsis and death. To survive and proliferate in blood, the pathogen requires mechanisms to overcome the innate immune defenses and metabolic limitations of this host niche. We created a high-density transposon mutant library in YJ016, a strain representative of the most virulent V.

In-Depth Proteomic Characterization of Classical and Non-Classical Monocyte Subsets.

Monocytes are bone marrow-derived leukocytes that are part of the innate immune system. Monocytes are divided into three subsets: classical, intermediate and non-classical, which can be differentiated by their expression of some surface antigens, mainly CD14 and CD16. These cells are key players in the inflammation process underlying the mechanism of many diseases.

In situ colorimetric quantification of silver cations in the presence of silver nanoparticles.

Silver ions (Ag(+)) can be quantified in situ in the presence of AgNPs by using a colorimetric sensing probe (3,3',5,5'-tetramethylbenzidine). Interestingly, it also enables detection of the Ag(+) adsorbed on the AgNP surface. This is relevant to design new methods to make AgNPs while ensuring the total reduction of Ag(+).

Inductively coupled plasma optical emission spectroscopy determination of trace element composition of argan oil.

A methodology based on inductively coupled plasma optical emission spectroscopy (ICP-OES) after microwave assisted acid digestion has been developed to determine the trace element content of Moroccan argan oil. Limit of detection values equal or lower than few mg/kg were obtained for all elements under study. To assure the accuracy of the whole procedure, recovery studies were carried out on argan oil samples spiked at different concentration levels from 10 to 200 µg/L.

Effect of ivermectin on the liver of gilthead sea bream Sparus aurata: a proteomic approach.

Gilthead sea bream Sparus aurata is the most commercialized Mediterranean aquacultured fish species. Ivermectin has recently (experimentally) started to be used to control ectoparasitic infestations in Mediterranean cultured marine fish. The potential hepatotoxicity of ivermectin was investigated in gilthead sea bream juveniles (35g) following oral administration at the recommended dose of 0.

Long-term performance of peat biofilters treating ethyl acetate, toluene, and its mixture in air.

Three laboratory-scale peat biofilters were operated at 90 s empty bed residence time (EBRT) for over a year. Biodegradation of ethyl acetate, toluene, or a 1:1 mixture were investigated. In first stage, inlet concentration was progressively increased from 0.

Specific roles of 5' RNA secondary structures in stabilizing transcripts in chloroplasts.

RNA secondary structures, e.g. stem-loops that are often found at the 5' and 3' ends of mRNAs, are in many cases known to be crucial for transcript stability but their role in prolonging the lifetime of transcripts remains elusive.