Aiding the conservation of two wooden Buddhist sculptures with 3D imaging and spectroscopic techniques

The conservation of Buddhist sculptures that were transferred to Europe at some point during their lifetime raises numerous questions: while these objects historically served a religious, devotional purpose, many of them currently belong to museums or private collections, where they are detached from their original context and often adapted to western taste. A scientific study was carried out to address questions from Museo d'Arte Orientale of Turin curators in terms of whether these artifacts might be forgeries or replicas, and how they may have transformed over time. Several analytical techniques were used for materials identification and to study the production technique, ultimately aiming to discriminate the original materials from those added within later interventions

Reversible Disruption of Pre-Pulse Inhibition in Hypomorphic-Inducible and Reversible CB1-/- Mice

Although several genes are implicated in the pathogenesis of schizophrenia, in animal models for such a severe mental illness only some aspects of the pathology can be represented (endophenotypes). Genetically modified mice are currently being used to obtain or characterize such endophenotypes. Since its cloning and characterization CB1 receptor has increasingly become of significant physiological, pharmacological and clinical interest. Recently, its involvement in schizophrenia has been reported. Among the different approaches employed, gene targeting permits to study the multiple roles of the endocannabinoid system using knockout (-/-) mice represent a powerful model but with some limitations due to compensation. To overcome such a limitation, we have generated an inducible and reversible tet-off dependent tissue-specific CB1-/- mice where the CB1R is re-expressed exclusively in the forebrain at a hypomorphic level due to a mutation (IRh-CB1-/-) only in absence of doxycycline (Dox). In such mice, under Dox+ or vehicle, as well as in wild-type (WT) and CB1-/-, two endophenotypes motor activity (increased in animal models of schizophrenia) and pre-pulse inhibition (PPI) of startle reflex (disrupted in schizophrenia) were analyzed. Both CB1-/- and IRh-CB1-/- showed increased motor activity when compared to WT animals. The PPI response, unaltered in WT and CB1-/- animals, was on the contrary highly and significantly disrupted only in Dox+ IRh-CB1-/- mice. Such a response was easily reverted after either withdrawal from Dox or haloperidol treatment. This is the first Inducible and Reversible CB1-/- mice model to be described in the literature. It is noteworthy that the PPI disruption is not present either in classical full CB1-/- mice or following acute administration of rimonabant. Such a hypomorphic model may provide a new tool for additional in vivo and in vitro studies of the physiological and pathological roles of cannabinoid system in schizophrenia and in other psychiatric disorders

The Pictorial Treatment of the 18th Century Painted Lambriggio in the Alcova Room of Palazzo Chiablese: Methodological Approach, Technical Solutions and Retouching

[EN] This paper illustrates the results of the diagnostic campaign, the problems that emerged and the choices made during the 2019 intervention in the Alcova room of Palazzo Chiablese, paying particular attention to the phase of aesthetic restitution of the polychrome wooden lambriggio with panels dated to the second half of the 18th century. The radical changes in the intended use of the environment during the 19th century, associated with the destruction that occurred during WW2, left indelible wounds on the painted artefacts. In particular, the panels have undergone repeated treatments such as to conceal, in some cases, the 18th century paintings, creating a strong visual discontinuity. The pictorial activity included diversified technical solutions, modulated according to the specific problems encountered: small retouching alternated with extensive reconstructions based on historical photographic documentation and on direct comparison with the decorative elements of the most preserved panels. In compliance with the conservative history of the artefacts an overall recovery project was developed aimed at the search for a new aesthetic unit capable of coherently communicating with the remaining fixed furniture and mobile environment. Gatti, A.; Russo, D.; Capezio, R.; Piccirillo, A.; Caldera, M.; Manchinu, P. (2023). The Pictorial Treatment of the 18th Century Painted Lambriggio in the Alcova Room of Palazzo Chiablese: Methodological Approach, Technical Solutions and Retouching. En 6th International Meeting on Retouching of Cultural Heritage, RECH6. Editorial Universitat Politècnica de València. 35-44. https://doi.org/10.4995/RECH6.2021.13479354

The northern-Italy Renaissance in a panel by Defendente Ferrari: A complete study with a multi-analytical investigation

Defendente Ferrari, one of the most important painters of the Piedmontese Renaissance, was extremely active in the early 16th century. His Madonna with Child and two Saints (1505–1510 ca.), which was originally located in the Collegiate Church of Carmagnola (Turin province, Italy) now in the collections of Palazzo Madama - Museo Civico d'Arte Antica in Turin, was recently analyzed and restored at the Centro Conservazione e Restauro La Venaria Reale, as part of a study and conservation project focused on the artist and his circle. This study presents an interdisciplinary and multi-analytical archaeometric approach resulting from the collaboration of several universities and research centers. The adopted protocol allowed for clarifying some peculiarities of the artist's painting technique, such as the use of the dotted - a technique applied to render the nuances, volume, and flesh tones of the figures - and that of thin black cross-hatched strokes, drawn to shape the clothes and to define the related volumes and folds. Moreover, specific degradation processes were studied, which apparently occur also in other contemporary artworks with similar features. Of particular interest is the alteration of the blue color of the Virgin's garment, made of azurite and presently strongly blackened. SWIR reflectography performed with a high-resolution InGaAs scanner prototype allowed for imaging both the detailed underdrawing and the careful hatching used to highlight the shadows. The combined application of optical microscopy, SEM-EDS, µ-Raman, FT-IR spectroscopy, and GC–MS has been fundamental for analyzing some specific pigments, binders, and varnishes, as well as for inferring the cause for Virgin's garment blackening. A complete mapping of the pigments was provided through the combination of FORS (350–2000 nm), portable µ-Raman, MA-XRF, and Hypercolorimetric Multispectral Imaging. The latter also allowed for observing the distribution of what is supposed to be either the original or the ancient organic finishing layer, which was maintained during the conservation treatment. This research has brought to an in-depth knowledge of the artist's painting technique and helped the adoption of the best choices for an effective and minimal-invasive restoration intervention15n

Startle response and percentage of PPI in IR-hCB1^-/-, CB1^-/- and WT mice: effect of Dox treatment.

<p>The startle amplitude (panel A) and % of PPI (panel B) are the mean±S.E.M. of WT (n = 13), CB1^-/- (n = 13), IR-hCB1^-/- (n = 15) and IR-hCB1^-/- Dox (n = 14) mice. For PPI the data are expressed as the average PPI response over the 3 prepulse intensities (see supplemental files for the figure illustrating PPI by prepulse intensity). ***P<0.0001 IR-hCB1^-/- Dox vs all other groups (Newman-Keuls Multiple Comparison test).</p

CB₁ receptor immunoreactivity in the hippocampal formation.

<p>Representative low-magnification (4 x) showing CB1-IR throughout the hippocampus of WT (A) and IR-hCB1^-/- (B) mice. Higher-magnification (20 x) of the CG3 displays a dense network of CB1 immunoreactive fibers in WT mice (C) almost undetectable in IR-hCB1^-/- animals (D). Enlarged images (60x), of CG3 area showing CB1R staining (green) in throughout the neuronal processes from WT (E) and transgenic mice (F). Nuclear staining of DNA with DAPI (blue) revealed that, contrary to the WT, in IR-hCB1^-/- the CB1-IR diffuses into cytoplasm and almost lacks in neuronal membranes and fibers.</p