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The possibility to use light in the visible spectrum to induce near-infrared luminescence in some materials, particularly Egyptian blue and related pigments, offers a significant advantage in terms of their detection. Since 2008, this property has been exploited to reveal the presence of those pigments even in tiny amounts on ancient and decayed surfaces, using a technical-photography method. This paper presents a new type of imaging device that enables real-time, easy, and inexpensive identification and mapping of Egyptian blue and related materials. The potential of the new tool is demonstrated by its effectiveness in detecting Egyptian blue within some prestigious sites: (a) Egyptian findings at Museo Egizio, Turin; (b) underground Roman frescoes at Domus Aurea, Rome; and (c) Renaissance frescoes by Raphael, Triumph of Galateaand Loggia of Cupid and Psyche,at Villa Farnesina, Rome. The device is based on night vision technology and allows an unprecedented fast, versatile, and user-friendly approach. It is employable by professionals including archeologists, conservators, and conservation scientists, as well as by untrained individuals such as students or tourists at museums and sites. The overall aim is not to replace existing photographic techniques but to develop a tool that enables rapid preliminary recognition, useful for planning the work to be carried out with conventional methods. The ability to immediately track Egyptian blue and related pigments, through real-time vision, photos, and videos, also provides a new kind of immersive experience (Blue Vision) and can foster the modern use of these materials in innovative applications and future technologies.

Within the frame of a collaboration among the Accademia Nazionale dei Lincei, XGLab-Bruker and ENEA, some of the Renaissance wall paintings decorating Villa Farnesina interiors have been investigated by macro-X-ray fluorescence (MAXRF). In this paper is presented and discussed a case study concerning some sketches discovered about 50 years ago during the detachment of painted curtains. Results have brought to light a palimpsest whose discussion calls into question the attribution proposed when it has been discovered.

An acquisition campaign of macro-X-ray fluorescence scanning measurements on the vault of the Loggia of Cupid and Psyche, frescoed by Raphael and his workshop in the Villa Farnesina (Rome), supplied the occasion of testing the potentialities for such diagnostic tool/technique in studying wall paintings in situ. In this paper, the methodological approach is considered in depth, to highlight significant problematics deriving from nature of materials, painting technique and spatial peculiarities of this kind of artwork, as well as from the treatment and decoding of raw data. Data obtained through a single-spot XRF campaign, carried out during the past restorations of the Loggia, have been considered for comparisons.

We studied the function, development and aging of the adult nervous system in the colonial tunicate Botryllus schlosseri. Adults, termed zooids, are filter-feeding individuals. Sister zooids group together to form modules, and modules, in turn, are linked by a shared vascular network to form a well-integrated colony. Zooids undergo a weekly cycle of regression and renewal during which mature zooids are replaced by developing buds. The zooid brain matures and degenerates on this 7-day cycle. We used focal extracellular recording and video imaging to explore brain activity in the context of development and degeneration and to examine the contributions of the nervous system and vascular network to behavior. Recordings from the brain revealed complex firing patterns arising both spontaneously and in response to stimulation. Neural activity increases as the brain matures and declines thereafter. Motor behavior follows the identical time course. The behavior of each zooid is guided predominantly by its individual brain, but sister zooids can also exhibit synchronous motor behavior. The vascular network also generates action potentials that are largely independent of neural activity. In addition, the entire vascular network undergoes slow rhythmic contractions that appear to arise from processes endogenous to vascular epithelial cells. We found that neurons in the brain and cells of the vascular network both express multiple genes for voltage-gated Na+ and Ca2+ ion channels homologous (based on sequence) to mammalian ion channel genes.

Using the MOLAB®non-invasive analytical mobile laboratory, we studied a finely illuminated sixteenth-century Persian manuscript at the Fitzwilliam Museum, Cambridge, UK, in collaboration with its Department of Manuscripts and Printed Books. Three miniatures belonging to the manuscript, but ascribable to different periods, were analyzed in order to identify similarities and differences in the painting materials and techniques used by Safavid artists over a period of 150 years. The use of multiple analytical techniques indicated a common palette characterizing the three decorative schemes, along with some differences mainly regarding the pigment mixture used to obtain brown hues in the first scheme, as well as the presence of different mixtures in green and dark purple areas in the third scheme.

The development of diagnostic tools to assess restenosis risk after stent deployment may enable the intervention to be tailored to the individual patient, for example, by targeting the use of drug-eluting stent to high-risk patients, with the goal of improving safety and reducing costs. The CCNB1gene (encoding cyclin B1) positively regulates cell proliferation, a key component of in-stent restenosis. Therefore, we hypothesized that single-nucleotide polymorphisms in CCNB1may serve as useful tools in risk stratification for in-stent restenosis.

A combined experimental and computational study is carried out to understand the nature of the interfaces between dye-sensitized TiO2and cobalt-based electrolyte in the presence of a prototype coabsorbent, chenodeoxycholic acid (CDCA), employed in dye-sensitized solar cells (DSCs). It was recently reported that including CDCA both in the dye and in the electrolyte solutions substantially improved the performance of DSCs based on a Fc/Fc+electrolyte (Daeneke et al. Nat. Chem.2011, 3, 1755) . Here, we evaluate the individual and combined effect of CDCA as a surface coadsorbent and as an additive in DSCs based on a Co(II)/Co(III) electrolyte, in combination with two prototypical Ru(II) dyes, N719 and Z907. For both dyes, the concomitant use of CDCA in the dye bath and in the electrolyte solution leads to a significant improvement, by about a factor of 2, of the DSCs photovoltaic performances, allowing us to reach 5.3% efficiency with Z907. FT-IR analyses conducted on the solid and TiO2-adsorbed CDCA highlight the presence of surface-adsorbed interacting CDCA molecules, possibly creating a bulky insulating network on the TiO2surface. Computational analyses have been carried out to gain insight into the nature of the supramolecular aggregates occurring for CDCA on the TiO2surface.

It is well known that among hypertensive patients, an increased left ventricular mass (LVM) is a powerful predictor of cardiovascular morbidity and mortality. However, the mechanisms underlying LVM in hypertension are not completely understood, as the absolute value of blood pressure and other risk factors associated do not predict alone a definite LVM progression. Recently, the 9p21 chromosomal region has been consistently associated with coronary heart disease.

3,4-Dichloro-2(5H)-furanone, which has been prepared efficiently from mucochloric acid, has been transformed selectively into 4-aryl-3-chloro-2(5H)-furanones either by Suzuki- or Stille-type reactions. These monochloro derivatives have been used as precursors either to (Z)-4-aryl-5-[1-(aryl)methylidene]-3-chloro-2(5H)-furanones, including naturally occurring rubrolide M, or to unsymmetrical 3,4-diaryl-2(5H)-furanones. Some 2(5H)-furanone derivatives so prepared have been found to exhibit significant cytotoxic activity in vitro against the NCI three-cell-line panel, but limited cytotoxicity against the NCI human tumor 60 cell-line panel. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Colonial tunicates are the only chordate that possess two distinct developmental pathways to produce an adult body: either sexually through embryogenesis or asexually through a stem cell-mediated renewal termed blastogenesis. Using the colonial tunicate Botryllus schlosseri, we combine transcriptomics and microscopy to build an atlas of the molecular and morphological signatures at each developmental stage for both pathways. The general molecular profiles of these processes are largely distinct. However, the relative timing of organogenesis and ordering of tissue-specific gene expression are conserved. By comparing the developmental pathways of B. schlosseriwith other chordates, we identify hundreds of putative transcription factors with conserved temporal expression. Our findings demonstrate that convergent morphology need not imply convergent molecular mechanisms but that it showcases the importance that tissue-specific stem cells and transcription factors play in producing the same mature body through different pathways.

Supplemental Digital Content is available in the text.

In this paper a new compact and portable instrument for combined reflectance, time-resolved and steady-state fluorescence is presented. All the optical parts of the apparatus, carefully described in the text, were chosen after an extensive market survey in order to obtain the best performances coupled with the smallest dimensions. This instrument through the use of a dedicated multiple fiber optic probe, allows the complete photophysical behaviors of investigated materials to be collected from the same point of the analyzed surface. In this way, the resultant instrumental setup is a portable device, usable in situfor non destructive and non invasive diagnostic purposes in the field of cultural heritage. Preliminary results concerning organic dyes characterization, which is the main application of luminescence-based diagnostic techniques in artworks, are presented and compared with those previously obtained using separate devices. Concerning reflectance data, improvements in the deep detectable UV spectral range have been achieved switching from the integrating sphere of the old instrument to bifurcated optical fibers used as probe in the new one. Special attention was devoted to test the instrument capability in order to obtain the true emission spectrum, corrected for the selfabsorption effect, for which good results were found. This particular experimental procedure is strongly recommended, by a diagnostic point of view, to avoid distortions in the instrumental responses, namely the spectral shape and emission maximum wavelength of a fluorophore as function of the color saturation.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.