The role of left and right hemispheres in the comprehension of idiomatic language: an electrical neuroimaging study

Background  

The specific role of the two cerebral hemispheres in processing idiomatic language is highly debated. While some studies show the involvement of the left inferior frontal gyrus (LIFG), other data support the crucial role of right-hemispheric regions, and particularly of the middle/superior temporal area. Time-course and neural bases of literal vs. idiomatic language processing were compared. Fifteen volunteers silently read 360 idiomatic and literal Italian sentences and decided whether they were semantically related or unrelated to a following target word, while their EEGs were recorded from 128 electrodes. Word length, abstractness and frequency of use, sentence comprehensibility, familiarity and cloze probability were matched across classes.     

Novel copolyesters based on poly(alkylene dicarboxylate)s: 2. Thermal behavior and biodegradation of fully aliphatic random copolymers containing 1,4-cyclohexylene rings

Aliphatic poly(butylene 1,12-dodecanedioate) is an interesting biodegradable polyester characterized by high thermal stability and high crystallinity, but low melting temperature. In order to improve the performances of this polymer some novel fully aliphatic random copolyesters have been prepared starting from 1,4-butanediol and different molar ratio of 1,12-dodecanedioc acid and 1,4-cyclohexanedicarboxylic acid. The copolymers have a notable resistance to thermal degradation, thermal properties which vary as a function of the composition, and maintain the mechanical characteristics of the poly(alkylene dicarboxylate). In particular, the copolymer containing the 70 mol% of 1,4-cyclohexanedicarboxylate units improves the thermal properties of the poly(butylene 1,12-dodecanedioate) and presents a very high biodegradation rate, higher than those of the two parent homopolymers. This behavior has been correlated to the low level of crystallinity of the sample and to the composition of the amorphous phase. Therefore, these novel fully aliphatic copolymers represent an interesting new class of copolyesters which can balance good physical properties and high biodegradability.     

Diastereomeric half-sandwich Ru(II) cationic complexes containing amino amide ligands. Synthesis, solution properties, crystal structure and catalytic activity in transfer hydrogenation of acetophenone

The cationic complexes [(η⁶-arene)Ru(N,O-amino amide)X]Y (arene = p-cymene or indane; N,O-amino amide = (l)-proline amide or (l)-phenylalanine amide; X = Cl or I; Y = Cl, I or PF₆) have been synthesised and fully characterized by spectroscopic and analytical methods. In several cases (1a, 3a, 4a, 4b, 5) the metal configuration has been definitively established by X-ray analysis on single crystal. The lability of the metal center in solution has been studied by ¹H NMR and CD techniques. The highest configurational stability has been found in the complexes of the type [(η⁶-indane)Ru(N,O-proline amide)Cl]Y (4a,b). The complexes 1b, 2a-b, 3b, 4b and 5 are good precatalysts for the transfer hydrogenation of acetophenone in basic i-PrOH, with ee up to 76% at 30 °C. An ESI(+)-MS study of pre-catalytic solutions has provided useful information on the catalytic mechanism.     

Theoretical conformational study of six-membered cyclic allyl epoxides

Accurate “ab initio” calculations (MP2 method) were performed to outline the conformational profile of a number of six-membered cyclic allyl epoxides differing either in the nature of the cycle fragment (Y) bound to the unsaturation, or in the substitution at the endocyclic carbon bound to the epoxy ring and bridging the epoxy ring with the Y fragment. In particular, we calculated structures 4 (Y=CH₂), 5 (Y=O), 6 (Y=NH), 7 (Y=S), 8 (Y=CF₂), 9 (Y=NH₂ ⁺), 10 (Y=CO), 11 (Y=BH) and 12 (Y=NCOOH), where the fragment of the endocyclic carbon bridging “Y” and the epoxy fragment is either non-substituted (4a – 12a) or bears a methyl side chain trans (4b–12b) or cis (4c–12c) to the epoxidic oxygen. Saturated analogs (Y=O and Y=CH₂) were also computed to test the method and to evaluate the conformational profile in the absence of the unsaturation. Minimum energy conformations were found which differ in the relative position of the Y group and the epoxy oxygen, with respect to a plane containing the epoxy ring carbons and the adjacent saturated endocyclic carbon: they may be on the same side (conformer A) or on opposite sides (conformer B). Conformers A are generally more stable. The conjugation effect of Y with the double bond lowers the barrier between the two conformers to the extent that in a few cases only conformer A is associated with a minimum of energy. On the basis of the elongation of the allylic oxirane C–O bond, we postulated the order of reactivity of epoxides 4–12 in the oxirane ring-opening process, and a mechanism based on the more reactive conformer A. A comparison was also made between MP2 and DFT calculation methods.     

Estimation of dynamic strains in finite end-constrained pipes in seismic areas

The work presents an analysis of the dynamical response of a buried pipe under seismic excitation. The pipe is assumed to be of finite length and the Winkler model to schematize soil-structure interaction is considered. With reference to the boundary conditions of end-constrained pipe the axial motions are discussed. Careful numerical integrations are performed in order to prevent undesirable oscillations close to the discontinuities. The main result emphasized by the numerical analysis is that end-constrained finite length pipelines are subject to strains greater than infinite length pipes, or free-end finite length pipes.     

Time-division multiplexing of the orbital angular momentum of light

We present an optical setup for generating a sequence of light pulses in which the orbital angular momentum (OAM) degree of freedom is correlated with the temporal one. The setup is based on a single q plate within a ring optical resonator. By this approach, we demonstrate the generation of a train of pulses carrying increasing values of OAM, or, alternatively, of a controlled temporal sequence of pulses having prescribed OAM superposition states. Finally, we exhibit an "OAM-to-time conversion" apparatus that divides different input OAM states into different time bins. The latter application provides a simple approach to digital spiral spectroscopy of pulsed light.