Search results for "Earing"

ChemInform Abstract: A Theoretical Study of the Selectivity for the Domino [5 + 2]/[4 + 2] Cycloadditions of γ-Pyrones Bearing Tethered Alkenes with …

2010

Abstract Selectivity of the domino [5+2]/[4+2] cycloaddition reactions of a β-silyloxy-γ-pyrone bearing a tethered alkene with two substituted 1,3-butadienes have been theoretically studied at the B3LYP/6-31G∗//AM1 and B3LYP/6-31G∗ computational levels. Analysis of these results allow explaining the regio, stereo and chemoselectivity observed experimentally at these domino reactions. Selectivity outcome is reproduced by these calculations.

SUL METABOLISMO DEGLI ORGANI DI RATTO PORTATORE DI SARCOMA DA BENZOPIRENE

1955

Free aminoacids were estimated in benzopyrene sarcoma of rats and in some organs of the tumour-bearing rats (brain, heart, muscle, lung, liver, spleen, kidney). In the tumour the content changes according to the growth stage; in the advanced tumour a strong increase of serine-glycine, glutammic acid and treonine is observed. In the organs the free amino acid contents are diminished in the first stages of the tumour growth, while in the advanced stages there is a tendency to an increase with different values according to the organs. The oxidation process in the organ homogenate (with or without substrate addition) varies according to the stage of the tumour growth, more evidently in the org…

[3+2] Cycloaddition Reaction of C -Phenyl-N -methyl Nitrone to Acyclic-Olefin-Bearing Electron-Donating Substituent: A Molecular Electron Density The…

2018

Dipolar Relaxation in Functionalized Poly-p-phenylenes Bearing Ultrastrong Dipoles Perpendicular to the Backbone

2018

Local polymer dynamics are studied in polymers bearing dipoles rigidly attached to the backbone. The compounds are based on cyano-substituted dihydrobenzimidazoles bearing ultrastrong dipole moments (∼12 D per repeat unit) incorporated in a poly-p-phenylene backbone, giving rise to polymers with rigid dipoles perpendicular to the chain. They belong to type B polymers according to the Stockmayer classification. They are ideal model systems for studying rotational isomers in the gas phase and the self-assembly and local dynamics in the solid state. Gas phase calculations (DFT) provided the dipole moments, the energetic barriers, and the backbone conformation as a function of the dipole streng…

Transient birefringence of polymer melts in intermittent shear flow: Model analysis of the non-linear viscoelastic behaviour

1977

A non-linear viscoelastic model has been used to interpret transient flow birefringence in changing shear flow for a polymer melt. It is shown how the new model is consistent with the basic hypothesis of the linear stress-optical law. Stress growth in shear flow and relaxation after different amounts of shearing are compared with the predictions of the non-linear model. A good agreement between experimental data and theoretical predictions is found.

Steel Fibres: Effective Way to Prevent Failure of the Concrete Bonded with FRP Sheets

2016

Although the efficiency of steel fibres for improving mechanical properties (cracking resistance and failure toughness) of the concrete has been broadly discussed in the literature, the number of studies dedicated to the fibre effect on structural behaviour of the externally bonded elements is limited. This experimental study investigates the influence of steel fibres on the failure character of concrete elements strengthened with external carbon fibre reinforced polymer sheets. The elements were subjected to different loading conditions. The test data of four ties and eight beams are presented. Different materials were used for the internal bar reinforcement: in addition to the conventiona…

ChemInform Abstract: Organocatalytic Enantioselective Synthesis of Pyrazoles Bearing a Quaternary Stereocenter.

2016

An efficient one-pot asymmetric synthesis of pyrazoles bearing a chiral quaternary stereocenter has been developed. Quinine-derived thiourea catalyzed the enantioselective addition of pyrazolones to isatin-derived ketimines, providing the corresponding acetylated pyrazoles after in situ treatment with Ac2 O/Et3 N. The corresponding pyrazoles were afforded in high yields and excellent enantioselectivities.

Playing games in the cultural transformations in the second half of the twentieth century

2013

Audiological Findings in Children With Mucopolysaccharidoses Type I–IV

2017

Abstract Objective The aim of our study is to reflect hearing impairment of 23 children diagnosed with mucopolysaccharidosis (MPS) type I, II, III and IV. Methods Retrospective study of the clinical, audiological and treatment (medical vs surgical) findings of 23 children diagnosed with MPS type I, II, III and IV followed at a Tertiary Referral Hospital between 1997 and 2015. Results Six cases of MPS I, 8 of MPS II, 4 of MPS III and 5 of MPS IV were reviewed. 71.2% of patients had secretory otitis media (SOM) and 54% of patients had some type of hearing loss (HL). The behaviour of hearing loss was variable in each of the subgroups of MPS, finding greater involvement and variability in types…

Trentino iedzīvotāju radzenes centrālās daļas endotēlijs

2017

Bakalaura darbs uzrakstīts angļu valodā uz 30 lappusēm. Tas satur 18 attēlus, 8 tabulas un atsauces uz 23 literatūras avotiem. Pētījuma mērķis bija novērtēt tādu faktoru kā smēķēšana un kontaktlēcu lietošana ietekme uz radzenes endotēlija fizioloģiju. Metode: 45 pacientiem (vecumā no 29 līdz 58 gadiem) veikta aptauja par smēķēšanas ieradumiem un kontaktlēcu lietošanu. Ikvienam tika novērtēts endotēlijs, trīs reizes mērot ar Takagi 700GL spraugas lampu un EndoKer programmu. Rezultāti: Darbā netika atrasta nozīmīga korelācija starp dzimumu un vecuma grupām attiecībā uz kādu no ietekmes faktoriem. Kā arī nebija nozīmīga atšķirība starp smēķētājiem, kontaktlēcu lietotājiem un normālo populāciju…