47 research outputs found

    Evaluation of green solvents’ applicability for chromatic reintegration of polychrome artworks

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    Organic solvents are commonly used in restoration treatments, including chromatic reintegration on polychrome artworks. They are often toxic, and their vapors have a high impact on the environment and restorers, possibly causing pathological conditions. Therefore, this study aims at defining a new green solvent that can be used for chromatic reintegration, maintaining the volatility and the desired physical–chemical properties. The dispersion forces value (Fd) of ethyl lactate was taken as reference for a comparison with the proposed solvents, since it was found to be the most used solvent for the dilution of Maimeri Restoration Colors (MRC) and Gamblin Conservation Colors (GCC). Based on the Teas fractional parameters, six solutions based on acetals and ethanol have been proposed and tested. They were mixed with both MRC and GCC, and applied on prepared canvases. The difference between the backgrounds made with reference solvent and the one made with the proposed alternatives was evaluated through spectrocolorimetric measurements. Fourier-transform infrared spectroscopy in the attenuated total reflectance mode (FTIR-ATR) was performed on the applied layers to evaluate the presence of residual solvent inside them, while the volatility of the solvents was assessed by performing gravimetric analysis. The study showed that acetals, acetals’ blends, and acetals–ethanol mixtures represent suitable alternatives for the dilution of Gamblin Conservation Color and Maimeri Restoration Colors

    Public Shelter Admission Rates in Philadelphia and New York City: The Implications of Turnover for Sheltered Population Counts

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    Previous estimates of the size and composition of the U.S. homeless population have been based on cross-sectional survey methodologies. National enumeration efforts have yielded point-prevalence estimates ranging from 0.11 to 0.25 percent of the population. This study reports data from shelter databases in Philadelphia and New York City that record identifiers for all persons admitted and so make possible unduplicated counts of users. Unduplicated counts of shelter users yield annual rates for 1992 of about 1 percent for both cities and rates near 3 percent over three years in Philadelphia (1990–92) and over five years (1988–92) in New York City. The annual rates are three times greater than rates documented by point-prevalence studies. Shelter bed turnover rates are reported, as are average monthly first admission and readmission counts over a two-year period. Implications for future research and public policy are discussed

    Analytical Investigations of XIX–XX century paints. The study of two vehicles from the Museum for Communications of Frankfurt

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    Over the centuries, humans have developed different systems to protect surfaces from the influence of environmental factors. Protective paints are the most used ones. They have undergone considerable development over the years, especially at the turn of the 19th and 20th centuries. Indeed, between the two centuries, new binders and pigments have been introduced in the constituent materials of paints. The years in which these compounds have been introduced and spread in the paint market allow them to be defined as markers for the dating of paints and painted artifacts. The present work is focused on the study of the paints of two vehicles of the Frankfurt Museum of Communication, i.e., a carriage and a cart, that was designed for the German Postal and Telecommunications Service roughly between 1880 and 1920. The characterization of the paints was performed through in situ non-invasive techniques, i.e., portable optical microscopy and multispectral imaging, and laboratory non-destructive techniques, i.e., FT-IR ATR spectroscopy and SEM-EDS. The analytical investigation and the comparison with the data reported in the literature allowed us to determine the historicity of the paints, which are all dated before the 1950s

    A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors

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    A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 Ă— 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma.</p

    A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors

    Get PDF
    A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 Ă— 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma.</p

    Multicentre harmonisation of a six-colour flow cytometry panel for naĂŻve/memory T cell immunomonitoring

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    Background. Personalised medicine in oncology needs standardised immunological assays. Flow cytometry (FCM) methods represent an essential tool for immunomonitoring, and their harmonisation is crucial to obtain comparable data in multicentre clinical trials. The objective of this study was to design a harmonisation workflow able to address the most effective issues contributing to intra- and interoperator variabilities in a multicentre project. Methods. The Italian National Institute of Health (Istituto Superiore di Sanita, ISS) managed a multiparametric flow cytometric panel harmonisation among thirteen operators belonging to five clinical and research centres of Lazio region (Italy). The panel was based on a backbone mixture of dried antibodies (anti-CD3, anti-CD4, anti-CD8, anti-CD45RA, and anti-CCR7) to detect naive/memory T cells, recognised as potential prognostic/predictive immunological biomarkers in cancer immunotherapies. The coordinating centre distributed frozen peripheral blood mononuclear cells (PBMCs) and fresh whole blood (WB) samples from healthy donors, reagents, and Standard Operating Procedures (SOPs) to participants who performed experiments by their own equipment, in order to mimic a real-life scenario. Operators returned raw and locally analysed data to ISS for central analysis and statistical elaboration. Results. Harmonised and reproducible results were obtained by sharing experimental set-up and procedures along with centralising data analysis, leading to a reduction of cross-centre variability for naive/memory subset frequencies particularly in the whole blood setting. Conclusion. Our experimental and analytical working process proved to be suitable for the harmonisation of FCM assays in a multicentre setting, where high-quality data are required to evaluate potential immunological markers, which may contribute to select better therapeutic options

    Guidelines for the use and interpretation of diagnostic methods in adult food allergy

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    Food allergy has an increasing prevalence in the general population and in Italy concerns 8 % of people with allergies. The spectrum of its clinical manifestations ranges from mild symptoms up to potentially fatal anaphylactic shock. A number of patients can be diagnosed easily by the use of first- and second-level procedures (history, skin tests and allergen specific IgE). Patients with complex presentation, such as multiple sensitizations and pollen-food syndromes, frequently require a third-level approach including molecular diagnostics, which enables the design of a component-resolved sensitization profile for each patient. The use of such techniques involves specialists' and experts' skills on the issue to appropriately meet the diagnostic and therapeutic needs of patients. Particularly, educational programs for allergists on the use and interpretation of molecular diagnostics are needed

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    Interconversion of the thiazine and thiazolidine system of β -lactam antibiotics. Electrochemical cleavage of Kamiya's disulfide promoted by bromide ion

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    A new transformation of Kamiya's disulphide (1) into the bromopenam derivative (4) has been carried out by electrolyzing the disulphide (1) in protic solvents in the presence of Me4NBr. The transformation occurs through an intermediate episulphonium-bromide ion pair in which the bromide appears to tightly linked to the sulphu
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