Time-resolved broadband Raman spectroscopies; A unified six-wave-mixing representation

Excited-state vibrational dynamics in molecules can be studied by an electronically off-resonant Raman process induced by a probe pulse with variable delay with respect to an actinic pulse. We establish the connection between several variants of the technique that involve either spontaneous or stimulated Raman detection and different pulse configurations. By using loop diagrams in the frequency domain we show that all signals can be described as six wave mixing which depend on the same four point molecular correlation functions involving two transition dipoles and two polarizabilities and accompanied by a different gating. Simulations for the stochastic two-state-jump model illustrate the origin of the absorptive and dispersive features observed experimentally

Broadband infrared and Raman probes of excited-state vibrational molecular dynamics; Simulation protocols based on loop diagram

Vibrational motions in electronically excited states can be observed by either time and frequency resolved infrared absorption or by off resonant stimulated Raman techniques. Multipoint correlation function expressions are derived for both signals. Three representations for the signal which suggest different simulation protocols are developed. These are based on the forward and the backward propagation of the wavefunction, sum over state expansion using an effective vibration Hamiltonian and a semiclassical treatment of a bath. We show that the effective temporal ($\Delta t$) and spectral ($\Delta\omega$) resolution of the techniques is not controlled solely by experimental knobs but also depends on the system dynamics being probed. The Fourier uncertainty $\Delta\omega\Delta t>1$ is never violated

Kirkwood-Buff integration: A promising route to entropic properties?

Kirkwood-Buff integration (KBI) is implemented into the massively-parallel molecular simulation tool ms2 and assessed by molecular dynamics simulations of binary liquid mixtures. The formalism of Krüger et al. (P. Krüger et al., J. Phys. Chem. Lett. 4: 235–238, 2013) that adopts NVT ensemble data to the μVT ensemble is employed throughout. Taking advantage of its linear scaling with inverse system size, the extrapolation to the thermodynamic limit is analyzed. KBI are calculated with standard radial distribution functions (RDF) and two corrected RDF forms. Simulations in the NVT ensemble are carried out in the entire composition range for four Lennard-Jones mixtures, studying system size dependence by varying N = 4000, 8000 and 16000 molecules. Moreover, four mixtures of “real” components are considered with N = 4000. Thermodynamic factor, partial molar volumes and isothermal compressibility are calculated from KBI and compared with benchmark data from NpT ensemble simulations. The assessment shows that the formalism of Krüger et al. greatly improves KBI and that extrapolation is important, particularly for smaller systems.BMBF, 01IH16008E, Verbundprojekt: TaLPas - Task-basierte Lastverteilung und Auto-Tuning in der Partikelsimulatio

Newborn screening for inborn errors of metabolism and endocrinopathies: an update

Newborn screening for inborn errors of metabolism and endocrinopathies has expanded during the last two decades, mainly owing to the introduction of new technologies such as tandem mass spectrometry and DNA analysis. However, every expansion of the screening panel requires critical review, discussion, and pilot studies. Different legal regulations and ethical concerns may lead to different decisions. Without claiming to be comprehensive, this review tries to give an overview of newborn screening, including its main problems and target disease

Documents musicaux à la Médiathèque de l\u27Ircam

La numérisation des fonds de l\u27Ircam * s\u27est accompagnée de la fédération des sources et des ressources. Les choix stratégiques ont entraîné l\u27évolution du dispositif dont Michel Fingerhut nous invite à scruter les mutations

Depression and PTSD Co-Morbidity: What are We Missing?

Background: Posttraumatic stress disorder (PTSD) and depression comorbidity is highly common. Many hypotheses concerning this relation have been raised but the pertinent issues, including the wide clinical picture of this comorbidity, are still not clear. The current study aims to bridge these gaps. Method: We assessed PTSD, depression and comorbid indicators including dissociation, somatization, self- destructive behavior and suicidality among Israeli Yom Kippur war veterans at three time points (N = 349, 287, 301). Results: Dissociation, somatization, self-destructive behavior and suicidality were predicted separately by group (PTSD, depression and comorbidity) and time of measurement using ANOVA and Chi squared analyses. The ‘comorbidity’ group expressed significantly higher dissociation, somatization, self-destructive behavior and suicidality, revealing high vulnerability of this group. Somatization presented a curvilinear-like development, increasing between T1 and T2 and slightly declining at T3, especially among the ‘comorbidity’ group. Suicidality showed a constant increase along the three measurements, especially among the comorbidity group. Conclusions: A PTSD/depression comorbidity is both highly prevalent and long lasting and is often expressed concurrently with other related symptomatology, which causes further suffering and makes it more complicated for treatment. Implications for policy makers are briefly discussed