60 research outputs found
Innovative Method and Apparatus for Deep Cleaning of Soluble Salts from Mortars and Lithic Materials
Abstract A new method improves the quality and durability of decontamination by soluble salts, compared with conventional application of wraps. The salts inside the porous material are brought in solution by soaking with distilled water, then aspired by a suction nozzle applied to the sample surface, allowing the solution to move towards the surface. Finally, the method tested on plaster samples with different suction flows is effective in the cleaning. As every surface to be cleaned could be affected by different extent of deterioration, specific flows of suctions were investigated
Photocatalytic Fe-doped n-TiO2: From synthesis to utilization of in vitro cell models for screening human and environmental nanosafety
The utilization of different types nanomaterials (NMs) in environmental remediation and wastewater treatment requires information on the potential harmful effects on human and environmental health. In this light, the utilization of human cell models together with cells from lower organisms, representative of different environmental compartments, could represent a valuable tool for the in vitro screening of the potential toxicity of different NMs used in nanoremediation. Among NMs, n-TiO2, because of its peculiar optical and chemical properties, is widely applied for photosensitized UV oxidation of organic pollutants. Moreover, development in design of metal- and non metal- doped TiO2 with extended photocatalytic activity in the visible region represents the subject of ongoing research. In this work, the cytotoxic effects of three different types of recently synthetized Fe-doped n-TiO2 were compared in two cell models widely utilized for screening cellular toxicity of NMs in humans and aquatic organisms, human vascular endothelial cells (HECV) and immune cells (hemocytes) of the marine invertebrate, the mussel Mytilus spp, respectively. Parallel studies were carried out using N-doped n-TiO2. The results indicate both distinct and common behavior (agglomeration state) in different media (human cell culture medium and mussel hemolymph serum) and biological effects (cytotoxicity, nitric oxide production) of different types of doped- n-TiO2 in different cell models. Although in vitro studies represent a first step in the toxicological assessment of NMs, studies comparing their effects on human and aquatic invertebrate cells that take into account the effects of different exposure media represent an useful tool for evaluating potential cytotoxicity of those NMs, like TiO2-based photocatalytic NMs, widely applied in environmental remediation, and whose potential risks are poorly understood
Solid-phase extraction of vanadium(V) from teainfusions and wines on immobilized nanometer titanium dioxide followed by ICP-OES analysis
Nanosized titanium dioxide immobilized on silica gel was synthesized and used as fixedbed
phase for V(V) pre-concentration, followed by inductively coupled plasma optical emission
spectroscopy (ICP-OES) analysis. Three different sorbents were prepared by sol\u2013gel method starting
from a mixture of titanium isopropoxide, 2-propanol and water, and characterized by X-ray
powder diffraction (XRPD), scanning electron microscopy (SEM) and BET analysis. V(V), the
most stable and toxic oxidation state of the element, present in water and beverages samples,
was selectively sorbed, pre-concentrated, quantitatively eluted by 0.1 M HCl and analyzed by
ICP-OES. The effectiveness of the procedure was first assessed on tap water enriched with 1 lg L1
of V(V) obtaining recoveries up to 92% (n= 4). The pre-concentration step was then optimized for
complex matrices such as tea infusions and red and white wines. The reliability of the procedure was
assessed on the same beverages samples spiked with 20\u2013250 lg L1. Quantitative recoveries (82\u2013
95%, n= 4) were assured avoiding any sample pre-treatment, generally essential in such complex
matrices, obtaining good precision (RSD< 12%, n= 3). The method was then applied to the
determination of V(V) in commercial tea infusions and wines
Enhancement of TiO2 NPs Activity by Fe3O4 Nano-Seeds for Removal of Organic Pollutants in Water
The enhancement of the photocatalytic activity of TiO2 nanoparticles (NPs), synthesized
in the presence of a very small amount of magnetite (Fe3O4) nanoparticles, is here presented
and discussed. From X-ray diffraction (XRD) and differential scanning calorimetry (DSC)
analyses, the crystallinity of TiO2 nanoparticles (NPs) seems to be affected by Fe3O4, acting as
nano-seeds to improve the tetragonal TiO2 anatase structure with respect to the amorphous one.
Photocatalytic activity data, i.e., the degradation of methylene blue and the Ofloxacin fluoroquinolone
emerging pollutant, give evidence that the increased crystalline structure of the NPs, even if correlated
to a reduced surface to mass ratio (with respect to commercial TiO2 NPs), enhances the performance of
this type of catalyst. The achievement of a relatively well-defined crystal structure at low temperatures
(Tmax = 150 \u25e6C), preventing the sintering of the TiO2 NPs and, thus, preserving the high density of
active sites, seems to be the keystone to understand the obtained results
Effects of ventilator settings, nebulizer and exhalation port position on albuterol delivery during non-invasive ventilation: an in-vitro study.
BACKGROUND:Few studies have investigated the factors affecting aerosol delivery during non-invasive ventilation (NIV). Our aim was to investigate, using a bench-top model, the effect of different ventilator settings and positions of the exhalation port and nebulizer on the amount of albuterol delivered to a lung simulator.
METHODS:
A lung model simulating spontaneous breathing was connected to a single-limb NIV ventilator, set in bi-level positive airway pressure (BIPAP) with inspiratory/expiratory pressures of 10/5, 15/10, 15/5, and 20/10 cmH2O, or continuous positive airway pressure (CPAP) of 5 and 10 cmH2O. Three delivery circuits were tested: a vented mask with the nebulizer directly connected to the mask, and an unvented mask with a leak port placed before and after the nebulizer. Albuterol was collected on a filter placed after the mask and then the delivered amount was measured with infrared spectrophotometry.
RESULTS:
Albuterol delivery during NIV varied between 6.7\u2009\ub1\u20090.4% to 37.0\u2009\ub1\u20094.3% of the nominal dose. The amount delivered in CPAP and BIPAP modes was similar (22.1\u2009\ub1\u200910.1 vs. 24.0\u2009\ub1\u200910.0%, p\u2009=\u20090.070). CPAP level did not affect delivery (p\u2009=\u20090.056); in BIPAP with 15/5 cmH2O pressure the delivery was higher compared to 10/5 cmH2O (p\u2009=\u20090.033) and 20/10 cmH2O (p\u2009=\u20090.014). Leak port position had a major effect on delivery in both CPAP and BIPAP, the best performances were obtained with the unvented mask, and the nebulizer placed between the leak port and the mask (p\u2009<\u20090.001).
CONCLUSIONS:
In this model, albuterol delivery was marginally affected by ventilatory settings in NIV, while position of the leak port had a major effect. Nebulizers should be placed between an unvented mask and the leak port in order to maximize aerosol delivery
Interactions of cationic polystyrene nanoparticles with marine bivalve hemocytes in a physiological environment: Role of soluble hemolymph proteins
none12The bivalve Mytilus galloprovincialis has proven as a suitable model invertebrate for evaluating the potential impact of nanoparticles (NPs) in the marine environment. In particular, in mussels, the immune system represents a sensitive target for different types of NPs. In environmental conditions, both NP intrinsic properties and those of the receiving medium will affect particle behavior and consequent bioavailability/uptake/toxicity. However, the evaluation of the biological effects of NPs requires additional understanding of how, once within the organism, NPs interact at the molecular level with cells in a physiological environment. In mammalian systems, different NPs associate with serum soluble components, organized into a "protein corona", which affects particle interactions with target cells. However, no information is available so far on the interactions of NPs with biological fluids of aquatic organisms. In this work, the influence of hemolymph serum (HS) on the in vitro effects of amino modified polystyrene NPs (PS-NH2) on Mytilus hemocytes was investigated. Hemocytes were incubated with PS-NH2 suspensions in HS (1, 5 and 50µg/mL) and the results were compared with those obtained in ASW medium. Cell functional parameters (lysosomal membrane stability, oxyradical production, phagocytosis) were evaluated, and morphological changes were investigated by TEM. The activation state of the signalling components involved in Mytilus immune response (p38 MAPK and PKC) was determined. The results show that in the presence of HS, PS-NH2 increased cellular damage and ROS production with respect to ASW medium. The effects were apparently mediated by disregulation of p38 MAPK signalling. The formation of a PS-NH2-protein corona in HS was investigated by centrifugation, and 1D- gel electrophoresis and nano-HPLC-ESI-MS/MS. The results identified the Putative C1q domain containing protein (MgC1q6) as the only component of the PS-NH2 hard protein corona in Mytilus hemolymph. These data represent the first evidence for the formation of a NP bio-corona in aquatic organisms and underline the importance of the recognizable biological identity of NPs in physiological exposure medium when testing their potential impact environmental model organisms. Although the results obtained in vitro do not entirely reflect a realistic exposure scenario and the more complex formation of a bio-corona that is likely to occur in vivo, these data will contribute to a better understanding of the effects of NPs in marine invertebrates.openCanesi, Laura; Ciacci, Caterina; Fabbri, Rita; Balbi, Teresa; Salis, Annalisa; Damonte, Gianluca; Cortese, Katia; Caratto, Valentina; Monopoli, Marco P; Dawson, Kenneth; Bergami, Elisa; Corsi, IlariaCanesi, Laura; Ciacci, Caterina; Fabbri, Rita; Balbi, Teresa; Salis, Annalisa; Damonte, Gianluca; Cortese, Katia; Caratto, Valentina; Monopoli, Marco P; Dawson, Kenneth; Bergami, Elisa; Corsi, Ilari
Antibacterial activity of standard and N-doped titanium dioxide-coated endotracheal tubes: an in vitro study
Objective: The aim of this study was to assess the antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa of two nanoparticle endotracheal tube coatings with visible light-induced photocatalysis. Methods: Two types of titanium dioxide nanoparticles were tested: standard anatase (TiO2) and N-doped TiO2 (N-TiO2). Nanoparticles were placed on the internal surface of a segment of commercial endotracheal tubes, which were loaded on a cellulose acetate filter; control endotracheal tubes were left without a nanoparticle coating. A bacterial inoculum of 150 colony forming units was placed in the endotracheal tubes and then exposed to a fluorescent light source (3700 lux, 300-700 nm wavelength) for 5, 10, 20, 40, 60 and 80 minutes. Colony forming units were counted after 24 hours of incubation at 37\ub0C. Bacterial inactivation was calculated as the percentage reduction of bacterial growth compared to endotracheal tubes not exposed to light. Results: In the absence of light, no relevant antibacterial activity was shown against neither strain. For P. aeruginosa, both coatings had a higher bacterial inactivation than controls at any time point (p < 0.001), and no difference was observed between TiO2 and N-TiO2. For S. aureus, inactivation was higher than for controls starting at 5 minutes for N-TiO2 (p = 0.018) and 10 minutes for TiO2 (p = 0.014); inactivation with N-TiO2 was higher than that with TiO2 at 20 minutes (p < 0.001), 40 minutes (p < 0.001) and 60 minutes (p < 0.001). Conclusions: Nanosized commercial and N-doped TiO2 inhibit bacterial growth under visible fluorescent light. N-TiO2 has higher antibacterial activity against S. aureus compared to TiO2
Self-Sustained Combustion Synthesis and Asbestos-Bearing Waste: Scaling Up From Laboratory Towards Pre-Industrial Size Plant
open3noopenLaura, Gaggero; Maurizio, Ferretti; Valentina, CarattoGaggero, Laura; Ferretti, Maurizio; Caratto, Valentin
Method of applying nanometric titanium dioxide onto a glassy support for environmental use
Surgery of ulcerative colitis. emergent or urgent operation for acute severe colitis. Surgical options.
More extensive and definitive procedures for ASC (IPAA) are technically feasible but proctectomy is rarely required for symptomatic relief at the moment of an emergent surgery. Furthermore these patients are in most cases nutritionally depleted and on high-dose steroids which increases the risk for an anastomotic complication
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