Search results for "Effects"

Different scenarios of electric mobility: Current situation and possible future developments of fuel cell vehicles in Italy

2020

The diffusion of electric vehicles in Italy has started but some complications weight its spread. At present, hybrid technology is the most followed by users, due particularly to socioeconomic factors such as cost of investment and range anxiety. After a deep discussion of the Italian scenario, the aim of the paper is to recognize whether fuel cell technology may be an enabling solution to overcome pollution problems and respect for the environment. The opportunity to use fuel cells to store electric energy is quite fascinating&mdash

Previous Training in the Water Maze

1999

It has been shown that acquisition rates in the water maze vary across strains of mice, although the differential effects of previous experience in this spatial task have been scarcely evaluated. The aim of the present study was to evaluate the effects of training in the water maze at an early age (2 months) in two strains of mice (NMRI and C57BL) using a longitudinal study. Mice with or without previous training were tested when they were 6 months, and retested when 10 months old. The results showed that trained NMRI mice performed better than all the other groups, both at test and retest, indicating that previous training had more beneficial effects in NMRI than in C57BL mice. These resul…

1,3-Dipolar cycloadditions of electrophilically activated benzonitrile N-oxides. Polar cycloaddition versus oxime formation.

2006

The reactions of electrophilically activated benzonitrile N-oxides (BNOs) toward 3-methylenephthalimidines (MPIs) have been studied using density functional theory (DFT) at the B3LYP/6-31G* level. For these reactions, two different channels allowing the formation of the [3 + 2] cycloadducts and two isomeric (E)- and (Z)-oximes have been characterized. The 1,3-dipolar cycloadditions take place along concerted but highly asynchronous transition states, while formation of the oximes is achieved through a stepwise mechanism involving zwitterionic intermediates. Both reactions are initiated by the nucleophilic attack of the methylene carbon of the MPIs to the carbon atom of the electrophilically…

How far the substituent effects in disubstituted cyclohexa-1,3-diene derivatives differ from those in bicyclo[2.2.2]octane and benzene?

2018

Substituents effects in cyclic diene derivatives are studied using quantum chemical modeling and compared to the corresponding effects in aromatic (benzene) and fully saturated (bicyclo[2.2.2]octane) compounds. In particular, electronic properties of the fixed group Y in a series of 3- and 4-X-substituted cyclohexa-1,3-diene-Y derivatives (where Y = NO2, COOH, COO− OH, O−, NH2, and X = NMe2, NH2, OH, OMe, Me, H, F, Cl, CF3, CN, CHO, COMe, CONH2, COOH, NO2, NO) are examined using the B3LYP/6-311++G(d,p) method. For this purpose, quantum chemistry models of the substituent effect: cSAR (charge of the substituent active region) and SESE (substituent effect stabilization energy) as well as trad…

High variability of edge effects on forest vegetation diversity

2012

National audience; The influence of edges on vegetation diversity in forest fragments is an important issue for biodiversity conservation because of the large part of temperate woodlands concerned. In numerous empirical studies, a general pattern has been identified; it is described as two zones: the edge where plant distribution is linked to the distance from the forest border, the core area where the variability of vegetation is not linked to this distance. We present results of a study aiming at measuring the edge effects on vegetation in forest fragments in south-western France and at identifying potential factors of their variability. Vegetation was sampled in 28 transects constituted …

Biogenic amines in fermented foods

2010

Food-fermenting lactic acid bacteria (LAB) are generally considered to be non-toxic and non-pathogenic. Some species of LAB, however, can produce biogenic amines (BAs). BAs are organic, basic, nitrogenous compounds, mainly formed through decarboxylation of amino acids. BAs are present in a wide range of foods, including dairy products, and can occasionally accumulate in high concentrations. The consumption of food containing large amounts of these amines can have toxicological consequences. Although there is no specific legislation regarding BA content in many fermented products, it is generally assumed that they should not be allowed to accumulate. The ability of microorganisms to decarbox…

Prenatal cocaine exposure alters spontaneous and cocaine-induced motor and social behaviors.

2005

The abuse of cocaine in pregnant women could affect emotional behaviors in their descendents. The aim of this work was to evaluate the effects of prenatal cocaine exposure on spontaneous and cocaine-induced motor and social behaviors in mice. Three kinds of prenatal treatment were used: non-treated animals; mice treated daily with physiological saline during the last week of pregnancy; and finally, those treated with cocaine (25 mg/kg) during the same period. Behavioral studies took place on adult males, which were housed in two different conditions: grouped (non-aggressive), or isolated (aggressive). Cocaine-pretreated animals exhibited slight differences in spontaneous motor activity, but…

Long-term effects on offspring of early exposure to biological and external factors

2000

Sterically crowded triazenides as novel ancillary ligands in copper chemistry

2011

Abstract We have synthesized copper salts MN3RR′ derived from the biphenyl- or m-terphenyl-substituted triazenes Tph2N3H (1a) and Dmp(Tph)N3H (1b) (Dmp = 2,6-Mes2C6H3 with Mes = 2,4,6-Me3C6H2; Tph = 2-TripC6H4 with Trip = 2,4,6-i-Pr3C6H2). The homoleptic copper triazenide [CuN3Tph2] (2a) was obtained in high yield from the metallation of 1a with mesityl copper in n-heptane, while the complex [CuN3(Dmp)Tph] (2b) was generated by the same method in situ only. Reaction of 2a with triphenylphosphane gave the 2:1 adduct [CuN3Tph2(PPh3)2] (3a), regardless of the used complex/donor ratio, while reaction of 2a or 2b with a stochiometric amount of t-butylisonitrile afforded the 1:1 adducts [Tph2N3Cu…

A CASCADE of effects of bisphenol A

2009

International audience