First attempt to quantify microplastics in Mediterranean Sabellaria spinulosa (Annelida, Polychaeta) bioconstructions.

This work focuses on the arenaceous reefs by the polychaete Sabellaria spinulosa and addresses microplastics pollution. The main aim is to assess microplastics amount in a bioconstruction located in the Adriatic coast of Italy (Mediterranean Sea) through a comparative approach: sea-floor sediment and bioconstruction samples were analysed to quantify microplastics absolute abundance in both substrates. A total of 431 MPs were found in the investigated substrates: respectively 85 % fibers and 15 % fragments. Multivariate analysis indicates that MPs within bioconstruction occur in higher abundances and with different morphologies than in sediment samples. The analysis of bioconstruction polished sections allowed for observation of MPs agglutinated in their original position: higher concentration is reported in inter-tube areas. Results suggest that physical characteristics of MPs could play a key-role in bioconstruction inclusion processes and raise questions on effective role of sabellariid bioconstructions as a trap for this pollutant in the littoral environment.

Mixed Zirconium Phosphate Bis-Phosphonomethyl Glycine from Nanocrystalline α-Zirconium Phosphate: A Tailored Suite for Gold Nanoparticles.

A novel synthetic approach was investigated for the preparation of nanoplatelets of mixed zirconium phosphate bis-phosphonomethyl glycine, ZPGly, by the reaction of a gel of nanocrystalline α-type zirconium phosphate with N,N-bis-phosphonomethyl glycine, H3Gly. The syntheses were carried out in the absence of hydrofluoric acid by changing both the reagent relative amounts and temperature. An H3Gly/Zr molar ratio >2 did not significantly improve the degree of crystallinity of the materials, while an increase of temperature from 80 °C to 120 °C improved the crystallinity; the best result was obtained with H3Gly/Zr molar ratio = 2 and with a temperature reaction of 120 °C. The sample consisted of nanoplatelets with the size in the range 20-40 nm, and it was successfully exfoliated by treatment with a solution of methylamine. By treatment of the ZPGly colloidal dispersions with HAuCl4, a color change from white to red-violet was observed, indicating the formation of gold nanoparticles. The size and morphology of the gold particles were affected by the degree of crystallinity and, in turn, by the composition of the ZPGly support. As a matter of fact, large micrometric Au particles with a cubo-octahedral morphology were obtained by using the less crystalline ZPGly_R2-80 sample, while interconnected Au particles, with a size of about 16 nm, were obtained by using ZPGly_R2-120. The samples exhibited an absorption maximum in the visible region due to the surface plasmon resonance of gold nanoparticles.

Hyper Cross-Linked Polymers as Additives for Preventing Aging of PIM-1 Membranes.

Mixed-matrix membranes (MMMs) are membranes that are composed of polymers embedded with inorganic particles. By combining the polymers with the inorganic fillers, improvements can be made to the permeability compared to the pure polymer membranes due to new pathways for gas transport. However, the fillers, such as hyper cross-linked polymers (HCP), can also help to reduce the physical aging of the MMMs composed of a glassy polymer matrix. Here we report the synthesis of two novel HCP fillers, based on the Friedel-Crafts reaction between a tetraphenyl methane monomer and a bromomethyl benzene monomer. According to the temperature and the solvent used during the reaction (dichloromethane (DCM) or dichloroethane (DCE)), two different particle sizes have been obtained, 498 nm with DCM and 120 nm with DCE. The change in the reaction process also induces a change in the surface area and pore volumes. Several MMMs have been developed with PIM-1 as matrix and HCPs as fillers at 3% and 10wt % loading. Their permeation performances have been studied over the course of two years in order to explore physical aging effects over time. Without filler, PIM-1 exhibits the classical aging behavior of polymers of intrinsic microporosity, namely, a progressive decline in gas permeation, up to 90% for CO2 permeability. On the contrary, with HCPs, the physical aging at longer terms in PIM-1 is moderated with a decrease of 60% for CO2 permeability. 13C spin-lattice relaxation times (T1) indicates that this slowdown is related to the interactions between HCPs and PIM-1.

More Efficient Prussian Blue Nanoparticles for an Improved Caesium Decontamination from Aqueous Solutions and Biological Fluids.

Any release of radioactive cesium-137, due to unintentional accidents in nuclear plants, represents a dangerous threat for human health and the environment. Prussian blue has been widely studied and used as an antidote for humans exposed to acute internal contamination by Cs-137, due to its ability to act as a selective adsorption agent and to its negligible toxicity. In the present work, the synthesis protocol has been revisited avoiding the use of organic solvents to obtain Prussian blue nanoparticles with morphological and textural properties, which positively influence its Cs+ binding capacity compared to a commercially available Prussian blue sample. The reduction of the particle size and the increase in the specific surface area and pore volume values compared to the commercial Prussian blue reference led to a more rapid uptake of caesium in simulated enteric fluid solution (+35% after 1 h of contact). Then, after 24 h of contact, both solids were able to remove >98% of the initial Cs+ content. The Prussian blue nanoparticles showed a weak inhibition of the bacterial luminescence in the aqueous phase and no chronic detrimental toxic effects.

Toluene Adsorption by Mesoporous Silicas with Different Textural Properties: A Model Study for VOCs Retention and Water Remediation.

In this work, different mesoporous silicas were studied as potential sorbents for toluene, selected as a model molecule of aromatic organic fuel-based pollutants. Three siliceous materials with different textural and surface properties (i.e., fumed silica and mesoporous Santa Barbara Amorphous (SBA)-15 and Mobil Composition of matter (MCM)-41 materials) were considered and the effect of their physico-chemical properties on the toluene adsorption process was studied. In particular, FT-IR spectroscopy was used to qualitatively study the interactions between the toluene molecule and the surface of silicas, while volumetric adsorption analysis allowed the quantitative determination of the toluene adsorption capacity. The combined use of these techniques revealed that textural properties of the sorbents, primarily porosity, are the driving forces that control the adsorption process. Considering that, under real conditions of usage, the sorbents are soaked in water, their hydrothermal stability was also investigated and toluene adsorption by both the gas and aqueous phase on hydrothermally pre-treated samples was studied. The presence of ordered porosity, together with the different pore size distribution and the amount of silanol groups, strongly affected the adsorption process. In toluene adsorption from water, SBA-15 performed better than MCM-41.

Non-Porous versus Mesoporous Siliceous Materials for CO2 Capture.

In this study, the adsorption properties of a Stöber silica-based material towards CO2 were evaluated for the first time. The use of Stöber silica as support is interesting for real technological applications mainly due to economic factors. Furthermore, a direct comparison between the non porous Stöber sample with an ordered porous material (based on MCM-41 silica) allowed to evaluate the effect of the porosity on the CO2 adsorption properties. In order to make silica materials reactive towards CO2, they were functionalized by introducing amino groups via grafting of 3-[2-(2-aminoethyl)aminoethyl]aminopropyltrimethoxysilane. After a qualitative study of the CO2 adsorption, the quantitative determination of CO2 adsorption capacity at 35 °C revealed that the mesoporous material is more efficient compared to the Stöber-based one (adsorption capacity values of 0.49 and 0.58 mol/kg for Stöber-based and mesoporous samples). However, since the difference in the adsorption capacity is only about 15 % and the Stöber-based sample is considerably cheaper, the non-porous sample should be considered as a favourable adsorbent material for CO2 capture applications.

On the adsorption of toluene on amorphous mesoporous silicas with tunable sorption characteristics.

The development of novel adsorbents for the purification of natural gas from aromatic hydrocarbons and the optimization of adsorption processes represent some of the most crucial environmental challenges. In this work, two amorphous mesoporous silica (AMS) samples with different sorption characteristics were prepared by modifying the synthesis method of amorphous mesoporous silica-aluminas, and tested as adsorbents of aromatic molecules for the purification of natural gas. The physico-chemical properties of the obtained materials were finely characterized by means of different experimental techniques (including FTIR and solid-state NMR) with the aim of determining their sorption and surface features. The adsorption capacity of the produced solids towards toluene, chosen as the reference of aromatic molecules, was determined by using FTIR, solid-state NMR spectroscopy and microgravimetric analysis. Finally, in view of applications under more realistic conditions, the adsorption properties of the AMS materials were also investigated after prolonged treatments in water.

A Porous Carbon with Excellent Gas Storage Properties from Waste Polystyrene.

In this paper, we describe the synthesis and gas adsorption properties of a porous carbonaceous material, obtained from commercial expanded polystyrene. The first step consists of the Friedel-Craft reaction of the dissolved polystyrene chains with a bridging agent to form a highly-crosslinked polymer, with permanent porosity of 0.7 cm 3 /g; then, this polymer is treated with potassium hydroxide at a high temperature to produce a carbon material with a porous volume larger than 1.4 cm 3 / g and a distribution of ultramicro-, micro-, and mesopores. After characterization of the porous carbon and determination of the bulk density, the methane uptake was measured using a volumetric apparatus to pressures up to 30 bar. The equilibrium adsorption isotherm obtained is among the highest ever reported for this kind of material. The interest of this product lies both in its excellent performance and in the virtually costless starting material.

On the Gas Storage Properties of 3D Porous Carbons Derived from Hyper-Crosslinked Polymers.

The preparation of porous carbons by post-synthesis treatment of hypercrosslinked polymers is described, with a careful physico-chemical characterization, to obtain new materials for gas storage and separation. Different procedures, based on chemical and thermal activations, are considered; they include thermal treatment at 380 °C, and chemical activation with KOH followed by thermal treatment at 750 or 800 °C; the resulting materials are carefully characterized in their structural and textural properties. The thermal treatment at temperature below decomposition (380 °C) maintains the polymer structure, removing the side-products of the polymerization entrapped in the pores and improving the textural properties. On the other hand, the carbonization leads to a different material, enhancing both surface area and total pore volume-the textural properties of the final porous carbons are affected by the activation procedure and by the starting polymer. Different chemical activation methods and temperatures lead to different carbons with BET surface area ranging between 2318 and 2975 m²/g and pore volume up to 1.30 cc/g. The wise choice of the carbonization treatment allows the final textural properties to be finely tuned by increasing either the narrow pore fraction or the micro- and mesoporous volume. High pressure gas adsorption measurements of methane, hydrogen, and carbon dioxide of the most promising material are investigated, and the storage capacity for methane is measured and discussed.

Combined solid-state NMR, FT-IR and computational studies on layered and porous materials.

Understanding the structure-property relationship of solids is of utmost relevance for efficient chemical processes and technological applications in industries. This contribution reviews the concept of coupling three well-known characterization techniques (solid-state NMR, FT-IR and computational methods) for the study of solid state materials which possess 2D and 3D architectures and discusses the way it will benefit the scientific communities. It highlights the most fundamental and applied aspects of the proactive combined approach strategies to gather information at a molecular level. The integrated approach involving multiple spectroscopic and computational methods allows achieving an in-depth understanding of the surface, interfacial and confined space processes that are beneficial for the establishment of structure-property relationships. The role of ssNMR/FT-IR spectroscopic properties of probe molecules in monitoring the strength and distribution of catalytic active sites and their accessibility at the porous/layered surface is discussed. Both experimental and theoretical aspects will be considered by reporting relevant examples. This review also identifies and discusses the progress, challenges and future prospects in the field of synthesis and applications of layered and porous solids.

Experimental Determination of the Molar Absorption Coefficient of n-Hexane Adsorbed on High-Silica Zeolites.

Determination of the molar absorption coefficients of the CH3 bending mode at ν˜ =1380 cm-1 (ϵ1380 ) of n-hexane adsorbed from the gas phase on two different dealuminated zeolites is derived by a combination of IR spectroscopy and microgravimetric analysis. High-silica zeolite Y (HSZ-Y) and zeolite ZSM-5 (with SiO2 /Al2 O3 ratios of 200 and 280, respectively) with different textural and surface features are selected to evaluate the effect of the pore structure and architecture on the value of ϵ1380 of the adsorbed n-hexane. Experimental data indicate that the molecule experiences a different adsorption environment inside zeolites; thus resulting in a significant change of the dipole moment and very different ϵ1380 values: (0.278±0.018) cm µmol-1 for HSZ-Y and (0.491±0.032) cm µmol-1 for ZSM-5. Experimental data are also supported by computational modeling, which confirms the effect of different matrices on the IR absorption intensity. This study reveals that the use of probe molecules for quantitative measurements of surface sites has to be judiciously adopted, especially if adsorption occurs in the restricted spaces of microporous materials.

Mesoporous Silica Scaffolds as Precursor to Drive the Formation of Hierarchical SAPO-34 with Tunable Acid Properties.

Using a distinctive bottom-up approach, a hierarchical silicoaluminophosphate, SAPO-34, has been synthesized using cetyl trimethylammonium bromide (CTAB) encapsulated within ordered mesoporous silica (MCM-41) that serves as both the silicon source and mesoporogen. The structural and textural properties of the hierarchical SAPO-34 were contrasted against its microporous analogue, and the nature, strength, and accessibility of the Brønsted acid sites were studied using a range of physicochemical characterization tools; notably probe-based FTIR and solid-state magic angle spinning (SS MAS) NMR spectroscopies. Whilst CO was used to study the acid properties of hierarchical SAPO-34, bulkier molecular probes (including pyridine, 2,4,6-trimethylpyridine and 2,6-di-tert-butylpyridine) allowed particular insight into the enhanced accessibility of the acid sites. The activity of the hierarchical SAPO-34 catalyst was evaluated in the industrially-relevant, acid-catalyzed Beckmann rearrangement of cyclohexanone oxime to ϵ-caprolactam, under vapor-phase conditions. These catalytic investigations revealed a significant enhancement in the yield of ϵ-caprolactam using our hierarchical SAPO-34 catalyst compared to SAPO-34, MCM-41, or a mechanical mixture of these two phases. The results highlight the merits of our design strategy for facilitating enhanced mass transfer, whilst retaining favorable acid site characteristics.

Method for Noninvasive Analysis of Proteins and Small Molecules from Ancient Objects.

Proteins and small molecules from ancient objects and cultural heritage can provide key information and contribute to study the context of objects and artists. However, all present-day protocols and strategies for the analysis of ancient samples are often invasive and require microsampling. Here, we present a new method for the noninvasive analysis of proteins and small molecules: the technique uses a special ethyl-vinyl acetate film functionalized with strong cation/anion exchange and C8 resins, for interacting with both proteins and small molecules present on the surface of the objects, followed by LC-MS/MS analysis. The new method was fully validated for the determination of both proteins and small molecules on several types of supports, showing excellent analytical performances such as, for example, R2 of the calibration curve of 0.98 and 0.99 for proteins and small molecules, low but very repeatable recoveries, particularly adequate for investigations on precious ancient samples that must not be altered by the analytical procedure. ESEM images and LED multispectral imaging confirmed that no damages or alterations occurred onto the support surfaces and no residues were left from the extractive film. Finally, the new method was applied for the characterization of the binders of a historical fresco of the XVI century from the Flemish painter Paul Brill and of a recently discovered fresco from Isidoro Bianchi (XVII century). Moreover the method was employed for the identification of the colorant used by Pietro Gallo (XIV century) on a wood panel. The method here reported can be easily applied to any other research on ancient precious objects and cultural heritage, since it does not require microsampling and the proteins/small molecules extraction can be performed directly in situ, leaving the object unchanged and intact.

Effect of zirconium nitride physical vapor deposition coating on preosteoblast cell adhesion and proliferation onto titanium screws.

STATEMENT OF PROBLEM: Titanium has long been used to produce dental implants. Problems related to its manufacturing, casting, welding, and ceramic application for dental prostheses still limit its use, which highlights the need for technologic improvements. The aim of this in vitro study was to evaluate the biologic performance of titanium dental implants coated with zirconium nitride in a murine preosteoblast cellular model. PURPOSE: The purpose of this study was to evaluate the chemical and morphologic characteristics of titanium implants coated with zirconium nitride by means of physical vapor deposition. MATERIAL AND METHODS: Chemical and morphologic characterizations were performed by scanning electron microscopy and energy dispersive x-ray spectroscopy, and the bioactivity of the implants was evaluated by cell-counting experiments. RESULTS: Scanning electron microscopy and energy dispersive x-ray spectroscopy analysis found that physical vapor deposition was effective in covering titanium surfaces with zirconium nitride. Murine MC-3T3 preosteoblasts were seeded onto titanium-coated and zirconium nitride-coated screws to evaluate their adhesion and proliferation. These experiments found a significantly higher number of cells adhering and spreading onto zirconium nitride-coated surfaces (P<.05) after 24 hours; after 7 days, both titanium and zirconium nitride surfaces were completely covered with MC-3T3 cells. CONCLUSIONS: Analysis of these data indicates that the proposed zirconium nitride coating of titanium implants could make the surface of the titanium more bioactive than uncoated titanium surfaces.

Ultrastructural analysis of nanoparticles and ions released in periprosthetic membranes.

PURPOSE: The distribution and relationship of hydroxyapatite debris, nanometric organic and metal wear particles and metal ions on periimplant interface membranes following aseptic and septic arthroplastic loosening were investigated. METHODS: Scanning electron microscopy and X-ray spectroscopic analysis were used to analyze debris and ion distribution. RESULTS: Hydroxyapatite debris appeared with different morphology in a particular distribution among several membranes. These differences may reflect the occurrence of different friction forces taking place between prosthesis and bone interface in the several types of prostheses studied. Metal wear particles were detected in greater numbers in membranes from noncemented prostheses compared with those from cemented ones. In contrast, more organic particles were present in membrane from cemented prosthesis. No differences were observed between aseptic and septic membranes. CONCLUSION: Our findings support the need to evaluate the occurrence of friction forces that periprosthetic bone debris production may induce to exacerbate cellular reactivity. Furthermore, cellular engulfment of debris and the high level of different ions released indicate the occurrence of a toxic environment that may induce failure of any reparative pathways.

Colonoscopic surveillance of first-degree relatives of colorectal cancer patients in a faecal occult blood screening programme.

BACKGROUND: In some Italian areas, colonoscopic surveillance of first-degree relatives (FDRs) of colorectal cancer (CRC) patients is provided as a part of local population-based faecal occult blood test (FOBT) screening programmes. The objective of the present study was to assess the feasibility and early results of this surveillance model. METHODS: Data from district screening centres were used to evaluate the process of identification and selection of eligible FDRs (residence in the Emilia-Romagna Region, age 40-75 years, no recent colonoscopy) of screen-detected CRC patients and the detected prevalence of disease. The probability for an FDR to undergo colonoscopy and to be diagnosed with CRC and advanced adenoma was estimated using the Kaplan-Meier method. The sex- and age-standardised ratio of detected prevalence to that expected based on results from a colonoscopy screening study of the Italian general population was estimated. RESULTS: Between 2005 and 2011, 9319 FDRs of 2437 screen-detected CRC patients (3.8 per patient) were identified and contacted. Their likelihood of being eligible for, and accepting, colonoscopy was 0.11 (95% confidence interval: 0.11-0.12). Among the 926 subjects undergoing colonoscopy, the prevalence of previous negative screening FOBT was 63%. Eleven CRCs (1.2%) and 100 advanced adenomas (10.8%) were detected. The standardised ratio of detected prevalence to that expected was 0.91 (95% confidence interval: 0.19-2.66) for CRC and 1.48 (1.04-2.05) for advanced adenoma. CONCLUSIONS: The procedure of selection of FDRs was extremely ineffective. Due to previous negative screening tests, the prevalence of disease was less than expected. A population-based FOBT screening programme is a highly unsuitable setting for the provision of surveillance to FDRs of CRC patients.

Theoretical prediction of high pressure methane adsorption in porous aromatic frameworks (PAFs).

The adsorption isotherms of methane in four micro- and mesoporous materials, based on the diamond structure with (poly)phenyl chains inserted in all the C-C bonds, have been simulated with Grand Canonical Monte Carlo technique. The pressure range was extended above 250 bar and the isotherms were computed at 298, 313, and 353 K, to explore the potentiality of these materials for automotive applications, increasing the capacity of high-pressure tanks or storing a comparable amount of gas at much lower pressure. The force field employed in the simulations was optimized to fit the correct behavior of the free gas in all the pressure range and to reproduce the methane-phenyl interactions computed at high quantum mechanical level (post Hartree-Fock). All the examined materials showed a high affinity for methane, ensuring a larger storage of gas than simple compression in all the conditions: two samples exceeded the target proposed by U.S. Department of Energy for methane storage in low-pressure fuel tanks (180 cm(3) (STP)/cm(3) at 35 bar and room temperature).

One-pot synthesis and physicochemical properties of an organo-modified saponite clay.

An organo-saponite clay containing intercalated cetyltrimethylammonium (CTA(+)) cations was synthesized by an efficient one-step hydrothermal method and was compared with a CTA-exchanged saponite prepared by a classical postsynthesis intercalation route. In both hybrid samples, surfactant loading up to 10% was achieved. A comparative investigation of the physicochemical properties of both solids was carried out by a multidisciplinary approach, by using a combination of spectroscopic, structural, and thermal characterization tools. Powder X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) data indicated that the one-pot-prepared solid showed that the presence of CTA(+) molecules in the synthesis gel did not affect the clay structure. In addition, thermal analysis suggested that the inorganic layers play an active role in stabilizing and protecting the surfactant molecules by increasing their thermal stability. A different arrangement of intercalated CTA(+) ions in the two hybrid clays was observed by solid state NMR in combination with Fourier transform infrared (FTIR) spectroscopy and assigned to a different all-trans/gauche conformation ratio of the surfactant depending on the synthetic method used to prepare the two final materials. The surfactant organization is also influenced by the lamellae charge density, which is different in the two organo-modified materials as found by (27)Al and (29)Si MAS NMR experiments.

Organic-inorganic hybrid saponites obtained by intercalation of titano-silsesquioxane.

The synthesis and characterization of two bifunctional composite materials based on synthetic saponite clays is here presented. These materials were prepared by intercalation of a Ti-containing aminopropylisobutyl polyhedral oligomeric silsesquioxane (Ti-NH(2) POSS) in synthetic saponite samples containing interlayer sodium (Na-SAP) or protons (H-SAP). Hybrid organic-inorganic materials, Ti-NHM-1 and Ti-NHM-2, were obtained upon ion exchange. Structural, spectroscopic, and thermal properties of both hybrid materials were investigated in detail along with their catalytic activity in cyclohexene oxidation.

[Continuing medical education and the Social Balance Sheet]. / Quale formazione in Sanità? Un confronto basato sulle evidenze. Educazione continua e Bilancio Sociale.

The social balance sheet is an instrument used to obtain a clear and transparent account, that helps to develop an analysis of the budget from the point of view of the stakeholders; this is not all that is required by law, but it takes into account the ability of the health institutions to obtain a collaboration with the neighboring environment and with the social issues that enter into the relationship. This could be a valuable tool also for educational purposes; it is an useful task to be performed by the health workers, and an opportunity to redefine the information needs through the analysis of the results achieved.