Raman analysis of multilayer automotive paints in forensic science: measurement variability and depth profile?

The aim of this work is to study the influence of several analytical parameters on the variability of Raman spectra of paint samples. In the present study, microtome thin section and direct (no preparation) analysis are considered as sample preparation. In order to evaluate their influence on the measures, an experimental design such as 'fractional full factorial' with seven factors (including the sampling process) is applied, for a total of 32 experiments representing 160 measures. Once the influence of sample preparation highlighted, a depth profile of a paint sample is carried out by changing the focusing plane in order to measure the colored layer under a clearcoat. This is undertaken in order to avoid sample preparation such a microtome sectioning. Finally, chemometric treatments such as principal component analysis are applied to the resulting spectra. The findings of this study indicate the importance of sample preparation, or more specifically, the surface roughness, on the variability of the measurements on a same sample. Moreover, the depth profile experiment highlights the influence of the refractive index of the upper layer (clearcoat) when measuring through a transparent layer.

An Empirical Investigation of Defense Interpretation Depth, Defensive Functioning, and Alliance Strength in Psychodynamic Psychotherapy.

The present study examined the relationship between depth of defense interpretations by therapists, and patient defensive functioning, on the therapeutic alliance in a sample of 36 patients undergoing short-term dynamic psychotherapy. Defense interpretation depth was defined as the degree to which therapist interpretations contained information regarding the motivation for patient defenses and historical origins of the defensive processes (Greensen, 1967). Mean depth of interpretation was compared between sessions that were identified beforehand as either high-alliance or low-alliance sessions using the Helping Alliance Questionnaire (HAq-II: Luborsky et al., 1996). Results indicated that defensive functioning was correlated to defense interpretation depth in low-alliance sessions. Moreover, mean depth of interpretation was also higher in low-alliance sessions, pointing to the possible "destabilizing" effects that these interpretations may have on both defensive functioning and the therapeutic alliance. These results are discussed within the context of previous studies of therapeutic technique in dynamic psychotherapy.