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We present an accurate simulation of the Raman spectrum of the carbon dioxide molecule in the 1150–1500 cm−1 spectral range, comparing the results obtained using the three polyad schemes found in the literature of this molecule. The description of the molecule with the algebraic U1(2)×U(3)×U2(2) local model encompasses both stretching and bending degrees of freedom. A detailed analysis of the Hamiltonian interactions for the three polyad schemes provides fittings with root mean square deviations in the range 0.14–0.20 cm−1, involving 19 parameters taking into account the 178 experimental term energies found in the literature. Using a limited subset of 9 experimental transition moments, we optimize 5 partial derivatives of the mean polarizability and simulate the Raman spectrum of CO2 for the three polyad schemes. Comparing the calculated results with the experimental spectrum, we obtain an overall good agreement for the three polyads. However, an inspection in detail of the spectrum seems to show a slight preference for polyad P212 albeit not due to the interaction characterizing the polyad but due to anharmonic effects and energy distribution. Finally, we assess the effect of the Fermi resonance over CO2 Raman line intensities. [ABSTRACT FROM AUTHOR]

Abstract: Several parameters related to the timing, grip force and load force involved in a precision grasping task were studied in patients with Parkinson’s disease (PD) at different moments of medication and healthy controls, using a sensorized anthropomorphic device which was totally adapted to the human hand. The aim of this work was to carry out an accurate study of the reach-load-grip-hold-place-release subtasks to identify any physical motor impairment, its relation to medication and Parkinsonian strategies. Twenty seven patients in ON and OFF-like medication moments, and twenty seven age-matched controls took part in the experiment, which consisted of using the index finger and the thumb to perform a precision motor task involving different experimental objects. Visual cues were used as distracting elements. Results showed several motor parameters impaired in OFF-like medication moment but attenuated in ON state, suggesting a medication effect on the performance of the task. [Copyright &y& Elsevier]