429 results on '"Privitera, V"'
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402. Innovative Polymeric Hybrid Nanocomposites for Application in Photocatalysis.
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Cantarella M, Impellizzeri G, Di Mauro A, Privitera V, and Carroccio SC
- Abstract
The immobilization of inorganic nanomaterials on polymeric substrates has been drawing a lot of attention in recent years owing to the extraordinary properties of the as-obtained materials. The hybrid materials, indeed, combine the benefits of the plastic matter such as flexibility, low-cost, mechanical stability and high durability, with them deriving from their inorganic counterparts. In particular, if the inorganic fillers are nanostructured photocatalysts, the originated hybrid systems will be able to utilize the energy delivered by light, catalysing chemical reactions in a sustainable pathway. Most importantly, since the nanofillers can be ad-hoc anchored to the macromolecular structure, their release in the environment will be prevented, thus overcoming one of the main restrictions that impedes their applications on a large scale. In this review, several typologies of hybrid photocatalytic nanomaterials, obtained by using both organic and inorganic semiconductors and realized with different synthetic protocols, were reported and discussed. In the first part of the manuscript, nanocomposites realized by simply blending the TiO
2 or ZnO nanomaterials in thermoplastic polymeric matrices are illustrated. Subsequently, the atomic layer deposition (ALD) technique is presented as an excellent method to formulate polymeric nanocomposites. Successively, some examples of polyporphyrins hybrid systems containing graphene, acting as photocatalysts under visible light irradiation, are discussed. Lastly, photocatalytic polymeric nanosponges, with extraordinary adsorption properties, are shown. All the described materials were deeply characterized and their photocatalytic abilities were evaluated by the degradation of several organic water pollutants such as dyes, phenol, pesticides, drugs, and personal care products. The antibacterial performance was also evaluated for selected systems. The relevance of the obtained results is widely overviewed, opening the route for the application of such multifunctional photocatalytic hybrid materials in wastewater remediation.- Published
- 2021
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403. Suitability of Different Titanium Dioxide Nanotube Morphologies for Photocatalytic Water Treatment.
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Farrugia C, Di Mauro A, Lia F, Zammit E, Rizzo A, Privitera V, Impellizzeri G, Buccheri MA, Rappazzo G, Grech M, Refalo P, and Abela S
- Abstract
Photocatalysis has long been touted as one of the most promising technologies for environmental remediation. The ability of photocatalysts to degrade a host of different pollutants, especially recalcitrant molecules, is certainly appealing. Titanium dioxide (TiO
2 ) has been used extensively for this purpose. Anodic oxidation allows for the synthesis of a highly ordered nanotubular structure with a high degree of tunability. In this study, a series of TiO2 arrays were synthesised using different electrolytes and different potentials. Mixed anatase-rutile photocatalysts with excellent wettability were achieved with all the experimental iterations. Under UVA light, all the materials showed significant photoactivity towards different organic pollutants. The nanotubes synthesised in the ethylene glycol-based electrolyte exhibited the best performance, with near complete degradation of all the pollutants. The antibacterial activity of this same material was similarly high, with extremely low bacterial survival rates. Increasing the voltage resulted in wider and longer nanotubes, characteristics which increase the level of photocatalytic activity. The ease of synthesis coupled with the excellent activity makes this a viable material that can be used in flat-plate reactors and that is suitable for photocatalytic water treatment.- Published
- 2021
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404. Acquired factor XIII deficiency in patients under therapeutic plasma exchange: A poorly explored etiology.
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Chuliber FA, Penchasky D, Santoro DM, Viñuales S, Otero V, Villagra Iturre M, Privitera V, Mezzarobba D, Burgos Pratx L, López MS, Barrera L, Schutz N, Arbelbide J, and Martinuzzo M
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- Adult, Factor XIII analysis, Humans, Male, Middle Aged, Retrospective Studies, Young Adult, Factor XIII Deficiency etiology, Plasma Exchange adverse effects
- Abstract
Introduction: Factor XIII (FXIII) deficiency may cause bleeding under certain clinical circumstances. Therapeutic plasma exchange (TPE) may lead to a transient deficiency., Objectives: To describe the clinical evolution of patients with acquired FXIII deficiency secondary to TPE., Methods: We respectively studied a cohort of consecutive patients from 2014 to 2019 who were treated with TPE with FXIII levels <50%. The FXIII was measured after the start of the TPE course, on days between the TPE sessions, due to suspected acquired deficiency. All TPE were performed using continuous flow cell separator. In all cases, the initial replacement fluid applied was albumin. Apheresis procedures were held at 24to 48 hours intervals., Results: Eighteen patients were included, 13 of them were recipients of kidney transplants. The main TPE prescription was humoral rejection. Median FXIII at diagnosis (measured on days between sessions of the TPE course) was 19%(IQR17-25). The median of apheresis procedures before measurement of FXIII was 3(IQR2-4). Among the total cohort, 10 patients suffered hemorrhages. None of the patients without history of kidney transplants had bleeding (n = 5), however, 10/13 with kidney transplants did. Five kidney transplant patients received therapy with FXIII concentrate because of life-threatening bleeding. In all cases, the bleeding stopped within the first 24 hours. All patients had their FXIII levels measured again after finishing the TPE course, with normal results., Conclusions: TPE is an under-diagnosed cause of acquired FXIII deficiency since routine coagulation tests remain unaltered. It might cause major bleeding, particularly in patients with a recent history of surgery like kidney transplants., (© 2020 Wiley Periodicals LLC.)
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- 2021
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405. Low Incidence of Symptomatic Thrombotic Events in Adult Patients Hospitalized with Coronavirus 19: A Retrospective Cohort Study.
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Vallone MG, Vazquez C, Chuliber FA, Privitera V, Ferraris A, Cantarella RF, Indo MF, Sanchez Thomas DM, Peuchot VA, and Vazquez FJ
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- Aged, Aged, 80 and over, Argentina epidemiology, Arterial Occlusive Diseases blood, Arterial Occlusive Diseases diagnosis, COVID-19 blood, COVID-19 diagnosis, Female, Humans, Incidence, Ischemic Stroke blood, Ischemic Stroke diagnosis, Ischemic Stroke epidemiology, Male, Middle Aged, Patient Admission, Pulmonary Embolism blood, Pulmonary Embolism diagnosis, Retrospective Studies, Thromboembolism blood, Thromboembolism diagnosis, Time Factors, Venous Thrombosis blood, Venous Thrombosis diagnosis, Arterial Occlusive Diseases epidemiology, COVID-19 epidemiology, Pulmonary Embolism epidemiology, Thromboembolism epidemiology, Venous Thrombosis epidemiology
- Abstract
Background: Since the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) pandemic, there have been many reports of increased incidence of venous thromboembolism and arterial events as a complication., Objective: To determine the incidence of symptomatic thrombotic events (TEs) in patients hospitalized for SARS-CoV2 disease (coronavirus 19 [Covid-19])., Methods: A retrospective single-center cohort study with adult patients with a positive reverse transcriptase-polymerase chain reaction (rt-PCR) for SARS-CoV2, included from the date of diagnosis of Covid-19 and followed for 90 days or until death., Results: A total of 1621 patients were included in this study. The median age was 73 years (interquartile range
25th-75th [IQR] 53-87 years) and 57% (913) were female. Overall mortality was 21.6% (348). The overall incidence of symptomatic TEs within 90 days of diagnosis was 1.8% (30 of 1621) occurring in 28 patients, including an incidence of pulmonary embolism of 0.9% (15, 95% confidence interval [CI] 0.60%-1.6%), deep venous thrombosis of 0.61% (10, 95% CI 0.2%-1%), ischemic stroke of 0.25% (4, 95% CI 0.09%-0.65%), and ischemic arterial events of 0.06% (1, 95% CI 0.008%-0.43%). No acute coronary syndrome events were recorded. The incidence of symptomatic TEs was significantly lower in the general ward than in intensive care units (1.2% vs 5.7%; p < .001). The median time since positive rt-PCR for SARS-CoV2 to symptomatic TE was 22.5 days (IQR 19-43 days). There was no significant difference in the proportion of patients receiving (53.6%) and not receiving thromboprophylaxis (66.5%) and the development of TEs., Conclusion: The overall incidence of symptomatic TEs among these patients was lower than the incidence previously reported.- Published
- 2021
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406. Nonimmune-acquired factor XIII deficiency: a cause of high volume and delayed postoperative hemorrhage.
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Chuliber FA, Schutz NP, Viñuales ES, Penchasky DL, Otero V, Villagra Iturre MJ, López MS, Mezzarobba D, Barrera LH, Privitera V, Arbelbide JA, and Martinuzzo ME
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- Adult, Aged, Blood Coagulation, Blood Coagulation Tests, Erythrocyte Transfusion, Factor XIII Deficiency blood, Factor XIII Deficiency therapy, Female, Humans, Male, Middle Aged, Postoperative Hemorrhage blood, Postoperative Hemorrhage therapy, Retrospective Studies, Factor XIII Deficiency complications, Postoperative Hemorrhage etiology
- Abstract
: Factor XIII (FXIII) levels may decrease because of surgical consumption. Acquired FXIII deficiency could be a cause of postoperative hemorrhage usually underdiagnosed in clinical practice. To determine the diagnosis confirmation rate of acquired FXIII deficiency in postsurgical patients with clinical suspicion and to compare the characteristics and evolution of patients with or without FXIII deficiency. We performed a retrospective cohort study, which included 49 inpatients who were attended at our university hospital from 2014 to 2018 with suspicion of acquired FXIII deficiency because of disproportionate postoperative hemorrhage. FXIIIA levels less than 50% was considered a deficiency. Persistence of bleeding for more than 48 h, drop in hematocrit points, red blood cells transfused units, hemoglobin levels 12-36 h after bleeding, and time elapsed from the procedure to the bleeding were assessed as outcome variables. Logistic regression was employed for both univariate and multivariate analyses. Of the 49 patients included, 27(55%) had FXIII deficiency, with a median level of 34% [interquartile range (IQR) 19-42]. Abdominal surgery was the most common [n = 21 (43%)]. All patients had routine coagulation tests within the hemostatic range. FXIII deficiency was associated with a drop of more than 4 points in hematocrit [OR 59.69 (95% CI 4.71-755.30)], red blood transfused units >2 [OR 45.38 (95% CI 3.48-590.65)], and delayed bleeding >36 h after surgery [OR 100.90 (95% CI 3.78-2695.40)]. Plasma-derived FXIII concentrate was administered to eight patients with life-threatening bleeding with resolution within 24 h. Only one deficient patient died from bleeding. FXIII levels were measured 15 days after diagnosis or more in 20 out of 27 deficient patients, with normal results. Acquired FXIII deficiency may be a frequent underdiagnosed entity that should be considered when high-volume and delayed postoperative hemorrhage is present in patients with hemostatic routine coagulation test results.
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- 2020
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407. Laser-Based Synthesis of Au Nanoparticles for Optical Sensing of Glyphosate: A Preliminary Study.
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Sortino AL, Censabella M, Munzi G, Boninelli S, Privitera V, and Ruffino F
- Abstract
Nowadays, gold nanoparticles Au nanoparticles (AuNPs) capture great interest due to their chemical stability, optical properties and biocompatibility. The success of technologies based on the use of AuNPs implies the development of simple synthesis methods allowing, also, the fine control over their properties (shape, sizes, structure). Here, we present the AuNPs fabrication by nanosecond pulsed laser ablation in citrate-solution, that has the advantage of being a simple, economic and eco-sustainable method to fabricate colloidal solutions of NPs. We characterized the stability and the absorbance of the solutions by Ultraviolet-Visible (UV-Vis) spectroscopy and the morphology of the AuNPs by Transmission Electron Microscopy. In addition, we used the AuNPs solutions as colorimetric sensor to detect the amount of glyphosate in liquid. Indeed, glyphosate is one of the most widely used herbicides which intensive use represents a risk to human health. The glyphosate presence in the colloidal AuNPs solutions determines the aggregation of the AuNPs causing the change in the color of the solution. The variation of the optical properties of the colloidal solutions versus the concentration of glyphosate is studied.
- Published
- 2020
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408. Ag/ZnO/PMMA Nanocomposites for Efficient Water Reuse.
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Di Mauro A, Farrugia C, Abela S, Refalo P, Grech M, Falqui L, Nicotra G, Sfuncia G, Mio A, Buccheri MA, Rappazzo G, Brundo MV, Scalisi EM, Pecoraro R, Iaria C, Privitera V, and Impellizzeri G
- Abstract
This work attempts to produce photocatalytic surfaces for large-scale applications by depositing nanostructured coatings on polymeric substrates. ZnO/poly(methyl methacrylate) (PMMA) composites were prepared by low-temperature atomic layer deposition (ALD) of ZnO on PMMA substrates. In addition, to increase the photocatalytic and antibacterial activities of ZnO films, Ag nanoparticles were added on ZnO surfaces using plasma-enhanced ALD. The morphology, crystallinity, and chemical composition of the specimens were meticulously examined by scanning and transmission electron microscopies, energy-dispersive X-ray spectroscopy, and X-ray diffraction analyses. The noteworthy photocatalytic activity of the nanocomposites was proved by the degradation of the following organic pollutants in aqueous solution: methylene blue, paracetamol, and sodium lauryl sulfate. The antibacterial properties of the samples were tested using Escherichia coli as a model organism. Moreover, the possible toxic effects of the specimens were checked by biological tests. The present results unambiguously indicate the Ag/ZnO/PMMA nanocomposite as a powerful tool for an advanced wastewater treatment technology.
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- 2020
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409. Intraluminal Brachytherapy in Unresectable Extrahepatic Biliary Duct Cancer: An Italian Pooled Analysis.
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Autorino R, Bisiello S, Pappalardi B, Privitera V, Buwenge M, Piccolo F, Masciocchi C, Tagliaferri L, Macchia G, Curti CD, Luppatteli M, Cerrotta A, Morganti AG, Valentini V, and Mattiucci G
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- Adult, Aged, Aged, 80 and over, Bile Duct Neoplasms diagnostic imaging, Bile Duct Neoplasms mortality, Cholangiocarcinoma mortality, Cholangiocarcinoma pathology, Cholangiocarcinoma radiotherapy, Female, Humans, Italy, Magnetic Resonance Imaging, Male, Middle Aged, Neoplasm Staging, Radiotherapy Dosage, Retrospective Studies, Tomography, X-Ray Computed, Treatment Outcome, Bile Duct Neoplasms pathology, Bile Duct Neoplasms radiotherapy, Bile Ducts, Extrahepatic pathology, Brachytherapy methods
- Abstract
Background/aim: To evaluate the outcome of patients with unresectable extrahepatic cholangiocarcinoma (CC) treated with external-beam radiotherapy (EBRT) and concurrent chemotherapy (CT) with or without intraluminal brachytherapy (ILBT) boost or with definitive ILBT., Patients and Methods: A pooled analysis of patients with non-metastatic unresectable CC was performed. They were treated in three different institution with EBRT plus CT with or without an ILBT boost. Some patients received only ILBT with curative dose., Results: Seventy-three patients were included in the analysis. Thirty-nine patients (53%) received EBRT treatment with ILBT boost (18 patients with CT during EBRT), while 28 patients (38%) were treated with EBRT (CT in 26 patients) and 6 patients (8.2%) with definitive ILBT (2 patients with CT). CT was administered including either the use of gemcitabine or 5-fluorouracil. With a median follow-up of 16 month (range=1-94 months), median overall survival (OS) was 16 months. Overall median LC was 16 months and patients who underwent ILBT had a better local control (LC) (p=0.018)., Conclusion: The role of ILBT in unresectable CC is not yet supported by robust evidence in the literature. However, within this limit, preliminary results seem to suggest an improved local control in patients treated with ILBT, almost comparable to the ones of standard chemo-radiotherapy (CRT)., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)
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- 2020
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410. The prognostic role of FDG PET/CT before combined radio-chemotherapy in anal cancer patients.
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Leccisotti L, Manfrida S, Barone R, Ripani D, Tagliaferri L, Masiello V, Privitera V, Gambacorta MA, Rufini V, Valentini V, and Giordano A
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- Female, Follow-Up Studies, Humans, Male, Middle Aged, Prognosis, Retrospective Studies, Anus Neoplasms diagnostic imaging, Anus Neoplasms therapy, Chemoradiotherapy, Fluorodeoxyglucose F18, Positron Emission Tomography Computed Tomography
- Abstract
Objective: We assessed the prognostic value of several FDG PET/CT parameters, measured within the primary tumor and the involved lymph nodes, before definitive radio-chemotherapy (RCT) in anal cancer patients., Methods: Anal cancer patients with positive baseline FDG PET/CT who underwent definitive RCT from May 2011 to February 2018 were retrospectively assessed. Primary tumour (T)-SUVmax, T-SUVpeak, T-SUVmean, T-MTV, T-TLG, whole-body (WB) MTV, and WB-TLG were measured. Kaplan-Meier curves, Cox-regression analysis, and logistic regression machine-learning technique were used to test for associations between clinical data, metabolic parameters, and outcomes as overall survival (OS), disease-specific survival (DSS), metastatic-free survival (MFS), disease-free survival (DFS), local relapse-free survival (LRFS), and colostomy-free survival (CFS)., Results: Fifty-nine patients were included in the study. Median follow-up was 28 months. Higher pre-treatment WB-MTV, T-TLG, and WB-TLG were associated with worse OS (p = 0.025, 0.021, and 0.02, respectively). PET parameters resulted also statistically significant for DSS, DFS, and CFS (p = 0.032, 0.043, 9 × 10
-4 for WB-TLG). Cox analysis showed that PET parameters are significant predictors of OS, DSS, DFS, CFS, and LRFS. On multivariate analysis, age, stage, T-SUVpeak, WB-MTV, and T-TLG resulted significantly related to OS. A further stratification for patients with advanced stage (cT3-4 any N or any cT, N + ) showed that MTV and TLG, measured within the primary tumor and the involved nodes, are significantly higher in patients with a worse prognosis. In this subgroup, cut-off values of T- and WB-TLG as well as T- and WB-MTV showed a statistically significant correlation with clinical outcomes., Conclusions: Pre-treatment metabolic parameters measured within the primary tumor and the involved nodes may represent additional new biomarkers for estimating prognosis in anal cancer patients, especially in advanced stage patients.- Published
- 2020
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411. Hybrid nickel-free graphene/porphyrin rings for photodegradation of emerging pollutants in water.
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Ussia M, Urso M, Miritello M, Bruno E, Curcuruto G, Vitalini D, Condorelli GG, Cantarella M, Privitera V, and Carroccio SC
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A novel hybrid photoactive material based on graphene foam (G) coupled with porphyrin-based polymers (Porph rings) was formulated by using a time-saving procedure to remove nickel from the final device. Specifically, Porph rings were spin coated onto the G platform with the double function of a visible-light photocatalyst and protective agent during nickel etching. The characterization of G-Porph rings was assessed by Scanning Electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL). The novel material showed photocatalytic ability in degrading different classes of pollutants such as the herbicide 2,4 dichlorophenoxyacetic acid (2,4-D), polyethylene glycol (PEG) as an ingredient of care and health products, and also the methylene blue (MB) dye. UV-Vis spectroscopy, total organic carbon (TOC) and soft mass spectrometry techniques were used to monitor the photocatalytic process. The best performance in terms of photocatalytic efficiency was exhibited versus PEG and MB degradation. Furthermore, to determine the individual contribution of Reactive Oxygen Species (ROS) produced, free radical and hole scavenging tests were also carried out. Finally, a detailed map of the photocatalytic degradation mechanisms was proposed, reporting also the calculation of Porph rings' Highest Occupied Molecular Orbital (HOMO) and Lowest Occupied Molecular Orbital (LUMO) energy level values., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2019
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412. Investigating microbial indicators of anthropogenic marine pollution by 16S and 18S High-Throughput Sequencing (HTS) library analysis.
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Buccheri MA, Salvo E, Coci M, Quero GM, Zoccarato L, Privitera V, and Rappazzo G
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- Aquatic Organisms classification, Biodiversity, Environmental Monitoring, Feces microbiology, Gene Library, Italy, Microbiota, Phylogeny, Aquatic Organisms genetics, High-Throughput Nucleotide Sequencing, RNA, Ribosomal, 16S genetics, RNA, Ribosomal, 18S genetics, Seawater microbiology, Water Microbiology, Water Pollution
- Abstract
High-Throughput Sequencing technologies are providing unprecedented inventories of microbial communities in aquatic samples, offering an invaluable tool to estimate the impact of anthropogenic pressure on marine communities. In this case study, the Mediterranean touristic site of Aci Castello (Italy) was investigated by High-Throughput Sequencing of 16S and 18S rRNA genes. The sampling area falls within a Marine Protected Area and, notwithstanding, features an untreated urban wastewater discharge. Seawater samples were collected close to the wastewater output (COL) and at a second station about 400 m further off (PAN), before and after a summer increase in population. Prokaryotic communities clustered according to stations, rather than to seasons. While PAN showed a typical, not impacted, marine microbial composition, COL was consistently enriched in Epsilonproteobacteria and Firmicutes. Protist communities showed a peculiar clustering, as COL at springtime stood alone and was dominated by Ciliophora, while the other samples were enriched in Dinophyta. Analysis of alternative, detectable by High-Throughput Sequencing, microbial indicators, including both faecal- and sewage-associated, allowed uncovering the different sources of pollution in coastal and anthropogenically impacted marine ecosystems, underpinning the relevance of High-Throughput Sequencing-based screening as rapid and precise method for water quality management., (© FEMS 2019.)
- Published
- 2019
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413. Mechanical milling: a sustainable route to induce structural transformations in MoS 2 for applications in the treatment of contaminated water.
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Cantarella M, Gorrasi G, Di Mauro A, Scuderi M, Nicotra G, Fiorenza R, Scirè S, Scalisi ME, Brundo MV, Privitera V, and Impellizzeri G
- Abstract
Two-dimensional (2D) nanomaterials have received much attention in recent years, because of their unusual properties associated with their ultra-thin thickness and 2D morphology. Besides graphene, a new 2D material, molybdenum disulfide (MoS
2 ), has attracted immense interest in various applications. On the other hand, ball-milling process provides an original strategy to modify materials at the nanometer scale. This methodology represents a smart solution for the fabrication of MoS2 nanopowders extremely-efficient in adsorbing water contaminants in aqueous solution. This work reports a comprehensive morphological, structural, and physicochemical investigation of MoS2 nanopowders treated with dry ball-milling. The adsorption performances of the produced nanopowders were tested using methylene blue (MB) dye and phenol in aqueous solution. The adsorption capacity as a function of ball-milling time was deeply studied and explained. Importantly, the ball-milled MoS2 nanopowders can be easily and efficiently regenerated without compromising their adsorption capacity, so to be reusable for dye adsorption. The eventual toxic effects of the prepared materials on microcrustacean Artemia salina were also studied. The present results demonstrate that ball-milling of MoS2 offers a valid method for large-scale production of extremely efficient adsorbent for the decontamination of wastewaters from several pollutants.- Published
- 2019
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414. Surface modification by vanadium pentoxide turns oxide nanocrystals into powerful adsorbents of methylene blue.
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Di Mauro A, Landström A, Concina I, Impellizzeri G, Privitera V, and Epifani M
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Hypothesis: If nanocrystals of such semiconductor as SnO
2 and TiO2 , which are not known as powerful adsorbents, have their surface modified by layer of V2 O5 , how will the adsorption properties be affected? Answering this question would provide a new set of surface properties to be designed by surface engineering of oxide nanocrystals., Experiments: SnO2 and TiO2 colloidal nanocrystals were prepared by coupling sol-gel and solvothermal synthesis. By co-processing with V chloroalkoxide and subsequent heat-treatment at 400-500 °C, surface deposition of V2 O5 layers was obtained. The methylene blue adsorption onto the prepared materials was tested and compared with the pure oxide supports. Cycling of the materials and analysis of the adsorption process was also investigated., Findings: The V-modified nanocrystals extracted ∼80% methylene blue from 1.5 × 10-5 M aqueous solution after 15 min only, contrarily to pure materials, which took up only 30% of the dye even after 120 min. Comparison with pure commercial V2 O5 showed that the peculiar adsorption properties were imparted by the surface deposition of the V2 O5 -like layers. This report demonstrates that new classes of adsorbing materials can be conceived by suitably coupling different metal oxides., (Copyright © 2018 Elsevier Inc. All rights reserved.)- Published
- 2019
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415. ZnO-pHEMA Nanocomposites: An Ecofriendly and Reusable Material for Water Remediation.
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Ussia M, Di Mauro A, Mecca T, Cunsolo F, Nicotra G, Spinella C, Cerruti P, Impellizzeri G, Privitera V, and Carroccio SC
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The design of new hybrid nanocomposites based on poly(2-hydroxyethylmethacrylate) (pHEMA) graphene oxide (GO) cryosponges, wherein ZnO nanolayers have been deposited to induce photocatalytic properties, is reported here. Atomic layer deposition at low temperature is specifically selected as the deposition technique to stably anchor ZnO molecules to the pendant polymer OH groups. Furthermore, to boost the pHEMA cryogel adsorption capability versus organic dyes, GO is added during the synthetic procedure. The morphology, the crystallinity, and the chemical composition of the samples are deeply investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction analyses, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Swelling properties, mechanical performance, and adsorption kinetics models of the hybrid materials are also evaluated. Finally, the adsorption and photocatalytic performance are tested and compared for all of the samples using methylene blue as a dye. Particularly, the adsorption efficiency of ZnO/pHEMA and ZnO/pHEMA-GO nanocomposites, as well as their in situ regeneration via photocatalysis, renders such devices very appealing for advanced wastewater treatment technology.
- Published
- 2018
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416. Freestanding photocatalytic materials based on 3D graphene and polyporphyrins.
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Ussia M, Bruno E, Spina E, Vitalini D, Pellegrino G, Ruffino F, Privitera V, and Carroccio SC
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A new concept in the formulation of hybrid nanostructured materials combining high quality graphene 3D supported by Nickel foam and polyporphyrins for visible light photocatalytic application is here reported. Our innovative approach involves the development of a freestanding device able to: i) offer a high surface area to bind the photosensitizers by π-π interactions, and ii) enhance stability and photocatalytic efficiency by using cyclic porphyrin polymers. For these purposes, homo- and co-polymerization reactions by using different porphyrin (free or zinc complexed) monomers were performed. The microscopic structures and morphology of graphene polymer nanocomposites were investigated by using Scanning Electron Microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Atomic Force Microscopy (AFM). Finally, photocatalytic activity under visible light irradiation of the obtained nanocomposites was tested, by using methylene blue (MB) as organic pollutant. The obtained data suggested that hindered cyclic polymeric structures stacked on graphene surface by non-covalent interactions, restrict the formation of non photoactive aggregates and, as a consequence, induce an enhancement of photocatalytic activity. Remarkably, our systems show a degradation efficiency in the visible-light range much higher than other similar devices containing nanoporphyrin units reported in literature.
- Published
- 2018
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417. Laser irradiation in water for the novel, scalable synthesis of black TiO x photocatalyst for environmental remediation.
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Zimbone M, Cacciato G, Boutinguiza M, Privitera V, and Grimaldi MG
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Since 1970, TiO
2 photocatalysis has been considered a possible alternative for sustainable water treatment. This is due to its material stability, abundance, nontoxicity and high activity. Unfortunately, its wide band gap (≈3.2 eV) in the UV portion of the spectrum makes it inefficient under solar illumination. Recently, so-called "black TiO2 " has been proposed as a candidate to overcome this issue. However, typical synthesis routes require high hydrogen pressure and long annealing treatments. In this work, we present an industrially scalable synthesis of TiO2 -based material based on laser irradiation. The resulting black TiOx shows a high activity and adsorbs visible radiation, overcoming the main concerns related to the use of TiO2 under solar irradiation. We employed a commercial high repetition rate green laser in order to synthesize a black TiOx layer and we demonstrate the scalability of the present methodology. The photocatalyst is composed of a nanostructured titanate film (TiOx ) synthetized on a titanium foil, directly back-contacted to a layer of Pt nanoparticles (PtNps) deposited on the rear side of the same foil. The result is a monolithic photochemical diode with a stacked, layered structure (TiOx /Ti/PtNps). The resulting high photo-efficiency is ascribed to both the scavenging of electrons by Pt nanoparticles and the presence of trap surface states for holes in an amorphous hydrogenated TiOx layer.- Published
- 2017
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418. Optical and photocatalytic properties of TiO 2 nanoplumes.
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Scuderi V, Zimbone M, Miritello M, Nicotra G, Impellizzeri G, and Privitera V
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Here we report the photocatalytic efficiency of hydrogenated TiO
2 nanoplumes studied by measuring dye degradation in water. Nanoplumes were synthesized by peroxide etching of Ti films with different thicknesses. Structural characterization was carried out by scanning electron microscopy and transmission electron microscopy. We investigated in detail the optical properties of the synthesized material and related them to the efficiency of UV photodegradation of methylene blue dye. The obtained results show that TiO2 nanoplumes act as an effective antireflective layer increasing the UV photocatalytic yield of the film.- Published
- 2017
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419. Novel synthesis of ZnO/PMMA nanocomposites for photocatalytic applications.
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Di Mauro A, Cantarella M, Nicotra G, Pellegrino G, Gulino A, Brundo MV, Privitera V, and Impellizzeri G
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The incorporation of nanostructured photocatalysts in polymers is a strategic way to obtain novel water purification systems. This approach takes the advantages of: (1) the presence of nanostructured photocatalyst; (2) the flexibility of polymer; (3) the immobilization of photocatalyst, that avoids the recovery of the nanoparticles after the water treatment. Here we present ZnO-polymer nanocomposites with high photocatalytic performance and stability. Poly (methyl methacrylate) (PMMA) powders were coated with a thin layer of ZnO (80 nm thick) by atomic layer deposition at low temperature (80 °C). Then the method of sonication and solution casting was performed so to obtain the ZnO/PMMA nanocomposites. A complete morphological, structural, and chemical characterization was made by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses. The remarkable photocatalytic efficiency of the nanocomposites was demonstrated by the degradation of methylene blue (MB) dye and phenol in aqueous solution under UV light irradiation. The composites also resulted reusable and stable, since they maintained an unmodified photo-activity after several MB discoloration runs. Thus, these results demonstrate that the proposed ZnO/PMMA nanocomposite is a promising candidate for photocatalytic applications and, in particular, for novel water treatment.
- Published
- 2017
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420. Modification of graphene oxide by laser irradiation: a new route to enhance antibacterial activity.
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Buccheri MA, D'Angelo D, Scalese S, Spanò SF, Filice S, Fazio E, Compagnini G, Zimbone M, Brundo MV, Pecoraro R, Alba A, Sinatra F, Rappazzo G, and Privitera V
- Subjects
- Animals, Anti-Bacterial Agents, Escherichia coli, Oxides, Spectrum Analysis, Raman, Graphite chemistry
- Abstract
The antibacterial activity and possible toxicity of graphene oxide and laser-irradiated graphene oxide (iGO) were investigated. Antibacterial activity was tested on Escherichia coli and shown to be higher for GO irradiated for at least three hours, which seems to be correlated to the resulting morphology of laser-treated GO and independent of the kind and amount of oxygen functionalities. X-ray photoelectron spectroscopy, Raman spectroscopy, dynamic light scattering and scanning electron microscopy (SEM) show a reduction of the GO flakes size after visible laser irradiation, preserving considerable oxygen content and degree of hydrophilicity. SEM images of the bacteria after the exposure to the iGO flakes confirm membrane damage after interaction with the laser-modified morphology of GO. In addition, a fish embryo toxicity test on zebrafish displayed that neither mortality nor sublethal effects were caused by the different iGO solutions, even when the concentration was increased up to four times higher than the one effective in reducing the bacteria survival. The antibacterial properties and the absence of toxicity make the visible laser irradiation of GO a promising option for water purification applications.
- Published
- 2016
- Full Text
- View/download PDF
421. Toxicity Evaluation of New Engineered Nanomaterials in Zebrafish.
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Brundo MV, Pecoraro R, Marino F, Salvaggio A, Tibullo D, Saccone S, Bramanti V, Buccheri MA, Impellizzeri G, Scuderi V, Zimbone M, and Privitera V
- Abstract
The effect of the nanoparticles on the marine organisms, depends on their size, chemical composition, surface structure, solubility and shape. In order to take advantage from their activity, preserving the surrounding environment from a possible pollution, we are trying to trap the nanoparticles into new nanomaterials. The nanomaterials tested were synthesized proposing a ground-breaking approach by an upside-down vision of the Au/TiO2 nano-system to avoid the release of nanoparticles. The system was synthesized by wrapping Au nanoparticles with a thin layer of TiO2. The non-toxicity of the nano-system was established by testing the effect of the material on zebrafish larvae. Danio rerio o zebrafish was considered an excellent model for the environmental biomonitoring of aquatic environments and the Zebrafish Embryo Toxicity Test (ZFET) is considered an alternative method of animal test. For this reason zebrafish larvae were exposed to different concentrations of nanoparticles of TiO2 and Au and new nanomaterials. As biomarkers of exposure, we evaluated the expression of metallothioneins by immunohistochemistry analysis and western blotting analysis also. The results obtained by toxicity test showed that neither mortality as well as sublethal effects were induced by the different nanomaterials and nanoparticles tested. Only zebrafish larvae exposed to free Au nanoparticles showed a different response to anti-MT antibody. In fact, the immunolocalization analysis highlighted an increase of the metallothioneins synthesis.
- Published
- 2016
- Full Text
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422. Correction: Enhancing carrier generation in TiO2 by a synergistic effect between plasmon resonance in Ag nanoparticles and optical interference.
- Author
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Cacciato G, Bayle M, Pugliara A, Bonafos C, Zimbone M, Privitera V, Grimaldi MG, and Carles R
- Abstract
Correction for 'Enhancing carrier generation in TiO2 by a synergistic effect between plasmon resonance in Ag nanoparticles and optical interference' by Giuseppe Cacciato et al., Nanoscale, 2015, 7, 13468-13476.
- Published
- 2015
- Full Text
- View/download PDF
423. Enhancing carrier generation in TiO2 by a synergistic effect between plasmon resonance in Ag nanoparticles and optical interference.
- Author
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Cacciato G, Bayle M, Pugliara A, Bonafos C, Zimbone M, Privitera V, Grimaldi MG, and Carles R
- Abstract
Silver nanoparticles have been embedded at a few nanometer distance from the free surface of titania/silica multilayers using low energy ion beam synthesis. Transmission electron microscopy shows the presence of 3 nm-sized crystalline particles. Reflectance spectroscopy on these composite substrates shows an increase of the light capture efficiency in the visible range. This behaviour is interpreted as a synergistic effect between plasmon polariton resonance and Fabry-Perot interferences. Plasmon-resonant Raman spectroscopy is deeply used to analyze, on one hand confinement of vibrations and electronic excitations in Ag NPs, and on the other hand coupling of polar TiO2 phonons with injected photo-generated carriers. It is shown how these new Ag/TiO2 nanocomposite films appear as very promising to enhance the efficiency and enlarge the spectral sensitivity of plasmo-electronics devices.
- Published
- 2015
- Full Text
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424. An enhanced photocatalytic response of nanometric TiO2 wrapping of Au nanoparticles for eco-friendly water applications.
- Author
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Scuderi V, Impellizzeri G, Romano L, Scuderi M, Brundo MV, Bergum K, Zimbone M, Sanz R, Buccheri MA, Simone F, Nicotra G, Svensson BG, Grimaldi MG, and Privitera V
- Subjects
- Adsorption, Catalysis, Coated Materials, Biocompatible chemical synthesis, Gold radiation effects, Light, Materials Testing, Metal Nanoparticles radiation effects, Methylene Blue chemistry, Methylene Blue radiation effects, Particle Size, Photochemistry methods, Surface Properties, Titanium radiation effects, Water Pollutants, Chemical chemistry, Water Pollutants, Chemical radiation effects, Gold chemistry, Metal Nanoparticles chemistry, Methylene Blue isolation & purification, Titanium chemistry, Water Pollutants, Chemical isolation & purification, Water Purification methods
- Abstract
We propose a ground-breaking approach by an upside-down vision of the Au/TiO2 nano-system in order to obtain an enhanced photocatalytic response. The system was synthesized by wrapping Au nanoparticles (∼8 nm mean diameter) with a thin layer of TiO2 (∼4 nm thick). The novel idea of embedding Au nanoparticles with titanium dioxide takes advantage of the presence of metal nanoparticles, in terms of electron trapping, without losing any of the TiO2 exposed surface, so as to favor the photocatalytic performance of titanium dioxide. A complete structural characterization was made by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The remarkable photocatalytic performance together with the stability of the nano-system was demonstrated by degradation of the methylene blue dye in water. The non-toxicity of the nano-system was established by testing the effect of the material on the reproductive cycle of Mytilus galloprovincialis in an aquatic environment. The originally synthesized material was also compared to conventional TiO2 with Au nanoparticles on top. The latter system showed a dispersion of Au nanoparticles in the liquid environment, due to their instability in the aqueous solution that clearly represents an environmental contamination issue. Thus, the results show that nanometric TiO2 wrapping of Au nanoparticles has great potential in eco-friendly water/wastewater purification.
- Published
- 2014
- Full Text
- View/download PDF
425. TiO2-coated nanostructures for dye photo-degradation in water.
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Scuderi V, Impellizzeri G, Romano L, Scuderi M, Nicotra G, Bergum K, Irrera A, Svensson BG, and Privitera V
- Abstract
The photocatalytic efficiency of a thin-film TiO2-coated nanostructured template is studied by dye degradation in water. The nanostructured template was synthesized by metal-assisted wet etching of Si and used as substrate for the deposition of a thin film of TiO2 (10 nm thick) by atomic layer deposition. A complete structural characterization was made by scanning and transmission electron microscopies. The significant photocatalytic performance was evaluated by the degradation of two dyes in water: methylene blue and methyl orange. The relevance of the reported results is discussed, opening the route toward the application of the synthesized nanostructured TiO2 for water purification.
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- 2014
- Full Text
- View/download PDF
426. Nanoporous Ge electrode as a template for nano-sized ( <5 nm) Au aggregates.
- Author
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Impellizzeri G, Romano L, Fraboni B, Scavetta E, Ruffino F, Bongiorno C, Privitera V, and Grimaldi MG
- Abstract
In this paper we present the extremely peculiar electrical properties of nanoporous Ge. A full and accurate electrical characterization showed an unexpected and extremely high concentration of positive carriers. Electrochemical analyses showed that nanoporous Ge has improved charge transfer properties with respect to bulk Ge. The electrode behavior, together with the large surface-to-volume ratio, make nanoporous Ge an efficient nanostructured template for the realization of other porous materials by electrodeposition. The pores were efficiently decorated by Au nanoparticles of diameter as low as 1-5 nm, prepared by electrochemical deposition. These new results demonstrate the potential and efficient use of nanoporous Ge as a nanostructured template for nano-sized Au aggregates, opening the way for the realization of innovative sensor devices.
- Published
- 2012
- Full Text
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427. Bilateral total hip arthroplasty in subjects with multiple epiphyseal dysplasia.
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Pavone V, Costarella L, Privitera V, and Sessa G
- Subjects
- Activities of Daily Living, Adult, Arthroplasty, Replacement, Hip instrumentation, Cohort Studies, Female, Follow-Up Studies, Hip Joint diagnostic imaging, Humans, Male, Quality of Life, Radiography, Retrospective Studies, Treatment Outcome, Arthroplasty, Replacement, Hip methods, Hip Joint surgery, Osteochondrodysplasias surgery
- Abstract
Multiple epiphyseal dysplasia (MED) is a rare autosomal dominant skeletal dysplasia caused by abnormalities in the gene(s) coding for type IX collagen and cartilage oligomeric matrix protein. Clinically, the disease is characterized by abnormalities in the epiphyseal cartilage of multiple joints. Orthopedic manifestations include pain and restricted mobility. The disorder, which has a predilection for the femoral head and acetabulum, usually presents from the third to the fourth decade with secondary hip osteoarthritis. We report on 7 subjects affected by multiple epiphyseal dysplasia, which presented hip osteoarthritis in their third decade of life and underwent staged bilateral total hip arthroplasty. All patients experienced pain relief and improved quality of life after surgical treatment.
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- 2009
- Full Text
- View/download PDF
428. Laparoscopic splenectomy reduces the need for platelet transfusion in patients with idiopathic thrombocytopenic purpura.
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Vecchio R, Cacciola E, Lipari G, Privitera V, Polino C, and Cacciola R
- Subjects
- Adult, Female, Humans, Laparoscopy, Male, Retrospective Studies, Platelet Transfusion, Purpura, Thrombocytopenic, Idiopathic surgery, Splenectomy methods
- Abstract
Objectives: Laparoscopic splenectomy has been increasingly used in patients with idiopathic thrombocytopenic purpura. Because it is associated with minimal abdominal trauma, platelet consumption could be reduced with the laparoscopic approach. The aim of this study was to analyze intraoperative bleeding and the need for apheresis platelets, comparing laparoscopic with open splenectomy., Methods: Records of 40 patients who underwent splenectomy (20 through laparoscopy and 20 through open surgery) for idiopathic thrombocytopenic purpura were retrospectively reviewed. Intraoperative bleeding and need of perioperative apheresis platelets were evaluated in both groups. Statistical evaluation was conducted using the Mann-Whitney rank test, and differences were considered significant at P<0.01., Results: The mean amount of intraoperative bleeding was less in the laparoscopic group (P<0.01). Apheresis platelets were necessary in all patients in the open group (2 units transfused in 55% and 1 unit in 45% of cases) and only in 30% of cases in the laparoscopic group (1 unit transfused in each case)., Conclusions: Laparoscopic splenectomy is a safe procedure also in patients at high risk for bleeding diathesis. In idiopathic thrombocytopenic purpura, laparoscopic splenectomy should be the gold-standard surgical treatment. Need of platelet transfusion is probably reduced when laparoscopic splenectomy is compared with open surgery in these patients.
- Published
- 2005
429. [Diagnostic value of pan-cavography in obstructed central venous return of intrinsic causes].
- Author
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Cotroneo GB, Salmeri L, Cavallaro V, Minutolo V, Turco F, Mondati E, Privitera V, and Fichera R
- Subjects
- Diagnosis, Differential, Female, Heart Diseases diagnosis, Humans, Middle Aged, Phlebography, Radiography, Thoracic, Thrombosis etiology, Tomography, X-Ray Computed, Vena Cava, Inferior diagnostic imaging, Thrombosis diagnostic imaging, Vena Cava, Superior diagnostic imaging
- Abstract
The authors, after having analyzed the clinical patterns and the causes producing cava syndrome, propose a sequential diagnostic approach to it, whose course makes use of radiological procedures more or less invasive, and of endoscopic and histobioptic techniques. Among radiological investigations pan-cavography has allowed the authors to formulate the diagnosis of limited venous return because of intrinsic causes, conferring so an aetiological connotation and a physiopathological correlation indispensable for a correct and rapid therapy of the uncommon "intrinsic cava syndrome" of two patients, suffering respectively from "idiopathic thrombosis of superior vena cava, concerning also the beginning of inferior vena cava" and from "Fiedler cardiomyopathy".
- Published
- 1982
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