Marble hydrophobicity tuned by Si-based coatings

Hydrophobic polymers applied on stone materials increase their durability against undesired weathering processes [1]. The achievement of a certain degree of surface hydrophobicity (reducing the water permeation) constitutes one of the main research focuses [2]. Herein, two commercial Si-based resins (e.g. Alpha\uaeSI30 and Bluesil\uaeBP9710), directly applied on Carrara marble substrates and a silanization process, by using trichloromethylsilane (TCMS), were adopted. Contact angle measurements were carried out to evaluate the hydrophobic features. Hence, since only in the case of TCMS a good hydrophobicity was achieved (\uf071 around 150\ub0), two commercial polysiloxane-based additives (e.g. TegoPhobe 1500N and TegoPhobe 1650) were added respectively to Alpha\uaeSI30 and Bluesil\uaeBP9710, according to their chemical compatibility. These auxiliary substances allowed to decrease the wettability features of marble. Furthermore, since all the investigated coatings could be used as stone materials protective agents, water capillary absorption and vapor permeability tests were performed. Also, in this case, TCMS revealed to be the most performing one among the adopted silane-based resins, thanks to the drastic reduction of absorbed water and the decrease of vapor permeability within the threshold value of 50%. Finally, the coatings stability was evaluated by accelerated ageing tests. References [1] Cappelletti G., Fermo P., Pino F., Pargoletti E., Pecchioni E., Fratini F., Ruffolo S.A., La Russa M.F., On the role of hydrophobic Si-based protective coatings in limiting mortar deterioration, Environ Sci Pollut Res, 22 (2015) 17733\u201317743. [2] Cappelletti G., Fermo P., Camiloni M., Smart hybrid coatings for natural stones conservation, Progress in Organic Coatings 78 (2015) 511\u2013516

Artificial neural networks for 3D cell shape recognition from confocal images

We present a dual-stage neural network architecture for analyzing fine shape details from microscopy recordings in 3D. The system, tested on red blood cells, uses training data from both healthy donors and patients with a congenital blood disease. Characteristic shape features are revealed from the spherical harmonics spectrum of each cell and are automatically processed to create a reproducible and unbiased shape recognition and classification for diagnostic and theragnostic use.Comment: 17 pages, 8 figure

The hydrophobicity modulation of glass and marble materials by different Si-based coatings

Hydrophobic polymers applied on hydroxylated surfaces increase their durability against undesired weathering processes. The achievement of a certain degree of surface hydrophobicity (reducing the water permeation) constitutes one of the main research focuses. Herein, two commercial Si-based resins (e.g. Alpha\uaeSI30 and Bluesil\uaeBP9710), directly applied on both glass and Carrara marble substrates, and a silanization process by using trichloromethylsilane (TCMS) were adopted. Contact angle measurements together with hysteresis determination and Surface Free Energy (SFE) were carried out to evaluate the hydrophobic features. Hence, since only in the case of TCMS a good hydrophobicity was achieved (\uf071 around 150\ub0), two commercial polysiloxane-based additives (e.g. TegoPhobe 1500N and TegoPhobe 1650) were added respectively to Alpha\uaeSI30 and Bluesil\uaeBP9710, according to their chemical compatibility. These auxiliary substances allowed to decrease the wettability features of either glass or marble. Furthermore, since all the investigated coatings could be used as stone materials protective agents, water capillary absorption and vapor permeability tests were performed. Also in this case, TCMS revealed to be the most performing one among the adopted silane-based resins, thanks to the drastic reduction of absorbed water and the decrease of vapor permeability within the threshold value of 50%. Finally, the coatings stability was evaluated by accelerated ageing tests

Durable Modified Polyacrylic Coatings for Cultural Heritage Protection

INTRODUCTION Deterioration phenomena of ancient and modern stone cultural heritage are natural and unrestrainable decay processes mainly arising from water adsorption and percolation into stone building materials1. Once water attacks and penetrates stone surfaces, several chemical, physical and biological degradation processes can occur altering significantly, and in some cases even irreversibly, the properties of stone materials. The application of hydrophobic coatings to stone surfaces is mandatory to protect stone artefacts from the deleterious effects occurring in the case of water exposition. The protective agent must possess several features, i.e. high compatibility with the substrate, high durability, transparency, easiness of application and removal, water-repellency, capability to avoid the attack of organic and inorganic contaminants; moreover, it should be permeable to water vapor. The aim of the present work was to synthesize new polymer coatings as stone protective with satisfactory water repellent properties and improved durability, thanks to the combined use of fluorinated and long alkyl chain monomers and without the use of any photo stabilizers agents. EXPERIMENTAL/THEORETICAL STUDY New types of polymer protectives were prepared via free radical polymerization between either 1H,1H,2H,2H-Perfluoro-octyl-methacrylate (POMA) or commercial stearyl methacrylate (STEA, Sigma Aldrich) and methacrylic monomers (methyl, MMA, and n-butyl, nBuMA, methacrylates)2,3. Specifically, POMA was synthesized via esterification reaction using methacryloyl chloride and 1H,1H,2H,2H-Perfluoro-1-octanol. RESULTS AND DISCUSSION The properties of the home-made hydrophobizing polymers in terms of macromolecular structure, molecular weights, thermal features and water repellency were determined. Furthermore, the long-term behavior of these polymeric protective agents was estimated by means of accelerated aging tests exploiting UV radiations (in according to UNI 10925:2001 standard method for 100h, 315-400 nm for UVA rays and 280-315 nm for UVB ones). Their behavior over time was checked via Size Exclusion Chromatography (SEC) by evaluating Mn and D data of aged polymeric samples (Table 1) and by Fourier Transform Infrared (FT-IR) spectroscopy. By evaluating Mn and D data reported in Table 1, all the synthesized polymers seem to be unaffected by UV aging. Thus, the present stable resins were applied on both natural (Botticino marble) and artificial (mortar) stone substrates and their wetting properties together with their absorption by capillarity and water vapour permeability were successfully assessed and compared. All the covered substrates show an increase of water contact angle of around 50\ub0 and a decrease in water absorption and permeation of about 50% and 20%, respectively. Lastly, in order to evaluate the stability of the applied coatings towards degradation induced by solar radiation and interaction with the atmospheric pollution, exposure to a typical polluted urban environment for some months have been carried out. For this purpose, the following analyses have been performed: contact angle measurements, SEM-EDS (Scanning Electron Microscopy with X-ray microanalysis), IC (Ion Chromatography), and colorimetric tests by CIELab elaboration. CONCLUSION The use of polymeric protectives is very advantageous in fields when the hydrophobic properties and high chemical stability are required. Within this context, the use of polymer resins bearing methacrylic and fluorinated monomers along the polymeric chain can be a way to create tailor-made water repellent materials with enhanced durability, without the addition of any stabilizing agent

Advanced mortar coatings for cultural heritage protection : Durability towards prolonged UV and outdoor exposure

In the present work, two kinds of hybrid polymeric\u2013inorganic coatings containing TiO2 or SiO2 particles and prepared starting from two commercial resins (Alpha\uaeSI30 and Bluesil\uaeBP9710) were developed and applied to two kinds of mortars (an air-hardening calcic lime mortar [ALM] and a natural hydraulic lime mortar [HLM]) to achieve better performances in terms of water repellence and consequently damage resistance. The two pure commercial resins were also applied for comparison purposes. Properties of the coated materials and their performance were studied using different techniques such as contact angle measurements, capillary absorption test, mercury intrusion porosimetry, surface free energy, colorimetric measurements and water vapour permeability tests. Tests were also performed to determine the weathering effects on both the commercial and the hybrid coatings in order to study their durability. Thus, exposures to UV radiation, to UV radiation/condensed water cycles and to a real polluted atmospheric environment have been performed. The effectiveness of the hybrid SiO2 based coating was demonstrated, especially in the case of the HLM mortar

An indoor air quality study at the Ambrosiana Art Gallery (Milan)

Indoor air quality in historical buildings and museums is receiving increasing concern nowadays among the scientific community. Many sources of pollutants, both gases and particles, are responsible for the accelerated decay of the works of art. Knowing the levels of indoor pollutants is of critical importance to apply conservation and preservation strategies of cultural heritage [1, 2]. Air quality at the Ambrosiana Art Gallery in Milan has been monitored (in the two periods October-November 2017 and March 2018) inside the room where the preparatory cardboard of the School of Athens (1509-1511), one of most important masterpieces by Raffaello Sanzio, is stored. The cardboard is currently undergoing restoration and will be exposed in a new showcase that will be realized according to the specific environmental and microclimatic conditions of the room. The objective of this study was to monitor the concentration and chemical composition of the aerosol particulate matter (PM) up to the nano fraction, which represents the most dangerous fraction for the works of art surfaces. The monitoring campaigns have been carried out in parallel in the Raffaello room (at present not accessible to visitors) and in a nearby room open to visitors. The set of instuments employed included: a TSP sampler (total suspended particles) (Tecora, Pollution Check, Bravo M2); a DustMonit (Contec) analyzer that measures the concentration of dust up to PM1 and provides 13 granulometric classes (up to 300 nm); a NanoScan Nanoparticle sizer 3910 (TSI) instrument that measures particles concentration up to 10 nm; two instruments for the determination of black carbon (BC) in continuous and in particular a SILIIS instrument (Sphere-Integrated Laser Induced Incandescence Spectroscopy) and a micro aethalometer (AE51 Magee Scientific). Quartz fiber filters have been employed to collect TSP samples to be submitted to chemical analysis. The filters have been fully chemically characterized: main ionic constituents and the carbonaceous fraction (i.e organic carbon, OC and elemental carbon, EC) have been analyzed by IC (ion chromatography) and TOT (thermal optical transmittance) respectively. A particles morphological characterization has been carried out on PM collected on polycarbonate filters by means of SEM-EDX (scanning electron microscopy coupled with energy dispersive X-ray spectroscopy). Outdoor PM concentrations, obtained for the two seasons (autumn 2017 and spring 2018) from ARPA monitoring stations placed in the city center, have been correlated with indoor data

Multiple Sclerosis in the Mount Etna Region: Possible Role of Volcanogenic Trace Elements

Background: Trace elements have been hypothesised to be involved in the pathogenesis of Multiple Sclerosis and volcanic degassing is the major natural sources of trace elements. Both incidence of Multiple Sclerosis in Catania and volcanic activity of Mount Etna have been significantly increased during the last 30 years. Due to prevailing trade winds direction, volcanic gases from Etna summit craters are mostly blown towards the eastern and southern sectors of the volcano. Objective: To evaluate the possible association between Multiple Sclerosis and exposure to volcanogenic trace elements. Methods: We evaluated prevalence and incidence of Multiple Sclerosis in four communities (47,234 inhabitants) located in the eastern flank and in two communities (52,210 inhabitants) located in the western flank of Mount Etna, respectively the most and least exposed area to crater gas emissions. Results: A higher prevalence was found in the population of the eastern flank compared to the population of the western one (137.6/100,000 versus 94.3/100,000; p-value 0.04). We found a borderline significantly higher incidence risk during the incidence study period (1980–2009) in the population of the eastern flank 4.6/100,000 (95% CI 3.1–5.9), compared with the western population 3.2/100,000 (95% CI 2.4–4.2) with a RR of 1.41 (95% CI 0.97–2.05; p-value 0.06). Incidence risks have increased over the time in both populations reaching a peak of 6.4/100,000 in the eastern flank and of 4.4/100.000 in the western flank during 2000–2009. Conclusion: We found a higher prevalence and incidence of Multiple Sclerosis among populations living in the eastern flank of Mount Etna. According to our data a possible role of TE cannot be ruled out as possible co-factor in the MS pathogenesis. However larger epidemiological study are needed to confirm this hypothesis.Publishede742596A. Monitoraggio ambientale, sicurezza e territorioJCR Journalope

Biological and molecular characterization of PNH-like lymphocytes emerging after Campath-1H therapy

Campath-1H, an anti-CD52 monoclonal antibody, is therapeutically active in lymphoproliferative and autoimmune diseases. After Campath-1H therapy, lymphocytes with a paroxysmal nocturnal haemoglobinuria (PNH) phenotype have been reported to emerge. We characterized a PNH-like lymphocyte population emerging after Campath-1H therapy, in a patient with fludarabine refractory B-cell chronic lymphocytic leukaemia (B-CLL). We demonstrated a reduction in PIG-A mRNA levels compared with controls, and of all cytokines tested [interleukin (IL)-4, IL-13, IL-2, interferon(IFN)-gamma, IL-6, IL-10, and tumour necrosis factor (TNF)-alpha], except transforming growth factor (TGF)-beta. Given the inhibitory activity of TGF-beta, its elevated levels may contribute to the selective pressure of Campath-1H, leading to the emergence of PNH-like lymphocyte

Plasma mitomycin C concentrations determined by HPLC coupled to solid-phase extraction

The aim of this study was to set up a method for quantification of plasma mitomycin C (MMC) concentrations during intravesical chemotherapy delivered in the presence of local bladder hyperthermia (HT). In comparison with existing methods, this assay, characterized by relative simplicity and efficiency, resulted in the facilitation of performance with nondedicated instrumentation or nonspecialized staff. Purification from plasma matrix was carried out by solid-phase extraction under vaccuum. The purified drug was then collected directly into the vials of the HPLC autosampler. Chromatographic analysis was performed on a reversed-phase C18 column with water:acetonitrile (85:15 by vol) as the mobile phase and the UV detector set at 365 nm. The use of porfiromycin as internal standard provided a method with good within-day precision (CV 6.0% at 5 micrograms/L, n = 6), linearity (0.5-50 micrograms/L), and specificity. The lower limit of detection (< or = 0.5 microgram/L) proved to be suitable for plasma pharmacokinetics monitoring in two tested patients treated with MMC + HT for superficial bladder cancer

Towards Novel Fluorinated Methacrylic Coatings for Cultural Heritage: A Combined Polymers and Surfaces Chemistry Study

In this work, new co- and ter-polymers of methyl methacrylate (MMA), ethyl methacrylate (EMA), and N-butyl methacrylate (nBuMA), containing just 1% mol 7 mol 121 of a fluorinated co-monomer, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-octyl methacrylate (POMA), were synthesized. After an UV accelerated aging test, the photo-chemical stability of the polymers prepared was determined by 1H NMR and FT-IR spectroscopy, size exclusion chromatography, differential scanning calorimetry and wettability measurements. The polymers were applied to Botticino tiles to achieve better performances in terms of water repellency and consequently deterioration resistance. One-year prolonged exposure to a real environment was conducted and the properties of the coated materials and their performances were studied using different surface techniques such as water contact angle (WCA) and colorimetric measurements (CIELaB), capillary absorption, permeability (RVP) tests and soluble salts determination. The effectiveness of the fluorinated methacrylic coatings was clearly demonstrated; among all the resins, the co-polymer MMA_POMA seems to be the most performing one. Furthermore, both the UV photo-chemical resistance and the easiness of removal was successfully studied