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We study the spectral and transport properties of a Mott insulator driven by a static electric field into a non-equilibrium steady state. For the dissipation, we consider two mechanisms: Wide-band fermion reservoirs and phonons included within the Migdal approximation. The electron correlations are treated via non-equilibrium dynamical mean field theory with an impurity solver suitable for strong correlations. We find that dissipation via phonons is limited to restricted ranges of field values around Wannier-Stark resonances. To cover the full range of field strengths, we allow for a small coupling with fermionic baths, which stabilizes the solution. When considering both dissipation mechanisms, we find that phonons enhance the current for field strengths close to half of the gap while lowering it at the gap resonance as compared to the purely electronic dissipation used by Murakami and Werner [arXiv:1804.08257]. Once phonons are the only dissipation mechanism, the current in the metallic phase is almost one order of magnitude smaller than the typical values obtained by coupling to a fermionic bath. In this case, the transport regime is characterized by an accumulation of charge in the upper Hubbard band described by two effective chemical potentials., Comment: 15 pages, 15 figures, data available at https://repository.tugraz.at/records/fnmzc-8x658

Background and Aims Herpes Zoster reactivation causes inflammatory and hemorrhagic reaction in the posterior roots of spinal nerves and sensitive ganglia. Postherpetic neuralgia (PHN)1 is a neuropathic pain that occurs in 25% of patients older than 502,3. Pharmacological therapy is often uneffective; intrathecal steroid injections and nerve blocks may be tried4. Serratus anterior plane block (SAPB)5 could provide effective analgesia. Methods We treated 2 female patients with PHN, unresponsive to medical therapies, 56 and 74 yo; pain was localized in the antero-lateral area of thorax, limiting free movements of ipsilateral arm. Pain was strong (NRS score 8 and 10), stabbing and burning, exacerbating in absence of stimuli and without relief during the night. We performed an ultrasound-guided SAPB with 0.25%-levobupivacaine 30 ml and dexamethasone 8 mg at 5th intercostal space. Results Both patients had immediate pain relief: NRS was 2–3 after 10 minutes, 0–1 after 2 hours. Benefit was substantially maintained over time: at 48 hours, resumption of pain was mild (NRS 2) in the first patient, moderate (NRS 4–5) in the second; in this patient we decided to perform another injection. NRS finally decreased to 2–3 and there was no need for further injections. At two months there was absence of pain for both. Conclusions Long-lasting SAPB with local anesthetic and steroids could be a safe and effective way to treat resistant PHN, and it should be performed as soon as possible to avoid incipit of chronic pain and improve patient quality of life and outcome. Further studies are necessary to confirm our preliminary data.

Zinc oxide (ZnO) is one of the main functional materials used to realize chemiresistive gas sensors. In addition, ZnO can be grown through many different methods obtaining the widest family of unique morphologies. However, the relationship between the ZnO morphologies and their gas sensing properties needs more detailed investigations, also with the aim to improve the sensor performances. In this work, seven nanoforms (such as leaves, bisphenoids, flowers, needles, etc.) were prepared through simple wet chemical synthesis. Morphological and structural characterizations were performed to figure out their growth mechanisms. Then, the obtained powders were deposited through screen-printing technique to realize thick film gas sensors. The gas sensing behavior was tested toward some traditional target gases and some volatile organic compounds (acetone, acetaldehyde, etc.) and compared with ZnO morphologies. Results showed a direct correlation between the sensors responses and the powders features (morphology and size), which depend on the specific synthesis process. The sensors can be divided in two behavioral classes, following the two main morphology kinds: aggregates of nanocrystals (leaves and bisphenoids), exhibiting best performances versus all tested gases and monocrystal based (stars, needle, long needles, flowers, and prisms).

Thick films of tungsten trioxide (WO3), tin dioxide (SnO2), and tungsten-tin (W-Sn) mixed oxides at different nominal Sn molar fraction (0.1 and 0.3) were prepared. The functional materials were synthesized and characterized by SEM, X-ray diffraction, specific surface area measurements (BET), UV-Vis-NIR and IR spectroscopies. The gas sensing measurements highlighted that the mixed oxides based sensors offer a better response towards NO2 with respect to pure WO3 being almost insensitive to CO.

Background and aims Approximately 21% of patients admitted to trauma centres with chest trauma present MRF.1 Severe pain associated can lead to hypoventilation and respiratory complications in 31% of cases.2 3 Epidural and multimodal analgesia versus opioids are recommended in pain management.2 Opioids present significant side effects. We hypothesized that SABP 4 5 could provide safe and effective analgesia, extended by addiction of dexamethasone to local anaesthetic solution, and reduce respiratory complications, enhancing recovery of a better mechanical lung function. Methods 4 patients (BMI 30±3, age 60±18) admitted to ED for politrauma with lateral and posterior MRF (6±2) and severe pain (NRS>5), impairing maximal inspiration and coughing, were treated with multimodal analgesia+ SAPB (ethics committee approval obtained). We injected 0,25%-levobupivacaine 30 ml and dexamethasone (8 mg) towards the serratus plane on the midaxillary line at 5th rib level with ultrasound guidance. We registered RR, PaO2/FiO2 and NRS at rest (NRSr), during maximal inspiration (NRSi) and coughing (NRSc) before SABP (T0), after 15 minutes (T1) and after 4h (T2). At T0 and T2 we performed diaphragmatic ultrasound (diaphragm thickening ratio%, DTRr and DTRi). Results All patients had benefits: NRSr, NRSi and NRSc strongly decreased at T1; benefits were maintained at T2 (Graph 1). Both DTRr and DTRi improved at T2 (Graph 2). Respiratory rate fell from 32±5 to 18±3 at T1, PaO2/FiO2 remained ≥270; deeper breathing allowed 20% reduction in FiO2. No patient asked for rescue analgesia. Analgesia duration was 43±6h. No patient had respiratory complication requiring mechanical ventilation. Conclusions Both clinical and instrumental patterns suggest that SAPB is safe and provides effective opioid-sparing analgesia in MRF. It improves diaphragm function and could reduce respiratory complications.

Background and aims Infection can seriously complicate surgical treatment of fractures (up to 30%)1; if significant tissue damage is involved, compromised vasculature impairs access of host defences and antibiotics to affected areas, leading to permanent functional loss. O3 is a gas that can be administered iv after melting with saline solution (10–80 mcg/mL); combination with biological water leads to formation of reactive oxygen and lipid oxidation products, thus activating biochemical pathways that increase: erythrocytes’ ATP and 2,3-DPG, NO release, platelets and neutrophil-phagocytic activity, antioxidant enzymes upregulation, staminal cells migration/differentiation at injured sites and re-endothelization.2 3 LRA allows post-operative pain control and vasodilation, improving microcirculation4 and antibiotic delivery to the infection site. Methods A 45-year-old woman (BMI 40) with severe femur nail infection, submitted to multiple surgical debridements and antibiotic therapies with poor effects during 3 weeks, was finally scheduled for hip disarticulation. as a last chance, lumbar epidural catheter was placed to optimize pain control and O3 was started (35 mcg/ml, 500 ml/day during 15 days) through CV access. No complication happened. Circulating endothelial progenitors cells (CEPs) were evaluated using monoclonal-antibodies labeled towards CD106+45- and CD90+45; blood samples were obtained at days 0, 7, and 15 after starting O3. Results At day 15 patient was free from infection: no clinical signs, wound healing (figure 1), negative cultural exams. Simultaneously increased levels of CEPs released from bone-marrow in response to flogosis fell, probably showing complete endothelial repair (figure 2). Conclusions Synergy between LRA and O3 in microvasculature recruitment is a challenge to heal severe infections after surgical treatment of fractures; CEPs levels could correlate with response to therapy.

Silks have been widely used as biomaterials due to their biocompatibility, biodegradability, and excellent mechanical properties. In the present work, native spider silk was used as organic template for controlled nucleation of hydroxyapatite (HA) nano-coating that can act as biomimetic interface. Different bio-inspired neutralization methods and process parameters were evaluated to optimize the silk functionalization. The morphology and chemical composition were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analysis and mechanical properties were studied through tensile tests. Results showed that the optimized protocol enabled a controlled and homogeneous nucleation of apatite nano-crystals while maintaining silk mechanical performances after mineralization. This study reports the optimization of a simple and effective bio-inspired nucleation process for precise nucleation of HA onto spider silk templates, suitable to develop high-performance hybrid interfaces for bone tissue engineering. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48739.

The comprehension of atmospheric pollution levels worldwide is a crucial issue for assessing the health consequences from human exposure to polluted air, and for identifying emission reductions that will be effective for minimizing the potential risks. Advanced interconnected sensors are required that could monitor on real-time toxic gaseous concentration. The success of these instruments depends on the reliability of these devices to quantify and disseminate the pollution levels to nearby citizens. Metal-oxide semiconductors are widely used as functional materials for gas sensing because of their chemo-resistive effect when interacting with gases. Mixed oxides are usually considered for the superior performances shown with respect to the single oxides. In this work, tungsten-tin mixed oxides with different Sn molar fraction (0.0013, 0.12, 0.33 and 0.39 named WS-1, WS-2, WS-3 and WS-4) were synthesized by sol-gel co-precipitation. The powders were characterized by ICP-OES analysis, specific surface area measurements, electron microscopy, X-ray diffraction, UV-Vis-NIR and FT-IR spectroscopies. The powders were also deposited through screen-printing technology, obtaining thick film gas sensors, on which measurements of conductance as a function of temperature, surface potential barrier and dynamical responses in the presence of oxidizing or reducing gases were carried out. Based on the studied properties, the mixed oxides can be divided into two groups: the WO3-like samples (WS-1, WS-2, WS-3) and the SnO2-like sample (WS-4). All samples present pure crystalline structures: this is a new result for the WO3-like samples. There is no literature data reporting about the introduction of so high Sn content in a WO3 structure. The combination of spectroscopic and electrical characterizations allowed the definition of an interpretative model that correlates the deepness of defect levels in the band gap of these materials to the values of the surface potential barrier in air and, as a consequence, to the electrical responses to oxidizing and reducing gases. (C) 2019 Elsevier B.V. All rights reserved.

This study concerns eight samples of ZnO powders, which can be classified in three categories: 3D-structure samples (ellipsoids, flowers), 2D-structure samples (commercial sample, nanosheets), 1D-structure samples (nanorods; short, long and irregular needles). Apart for the commercial sample, the others were synthesized through wet chemistry processes. The morphological and structural features of the ZnO powders were investigated with the purpose to understand how the friction behaviour is affected by the materials intrinsic properties. The tribological analysis was performed using a pin on disc tribometer, studying the influence of the material properties by a multivariate statistical approach. Results show that the abrasive nature of ZnO nanoforms is correlated with the crystallite dimensions. Spherical particles cause a higher damage on surfaces at the interface, with a consequent major change in the roughness. In the case of 1D-structure samples, the friction coefficient is directly proportional to the aspect ratio of the particles.

The double-crested cormorant (Phalacrocorax auritus) colony at Little Galloo Island, Lake Ontario has been a Great Lakes focal point of controversy regarding cormorant–fish interactions for over two decades. We examined cormorant diet and fish consumption at the colony from 1992 to 2013. During this time period, two events, management actions and round goby (Neogobius melanostomus) invasion, occurred that affected the number of fish consumed by cormorants and their diet composition. The purpose of this study was to evaluate the effects of round goby on the feeding ecology of cormorants and evaluate the efficacy of management actions on meeting cormorant population targets at the colony. Round goby first appeared in the diet in 2004 (0.8%) and within one year were the primary prey (29.3%). The presence of round goby in the diet of cormorants: (1) eliminated seasonal variability in diet composition, (2) reversed seasonal trends in the number of fish consumed daily, (3) increased daily fish consumption, and (4) significantly reduced the consumption of other species including yellow perch and smallmouth bass. Management actions, such as egg oiling and culling, were also effective in reducing nesting activity and the number of cormorant feeding days at the Little Galloo Island colony. There is evidence that the combination of management actions and round goby may have allowed some population recovery of yellow perch and smallmouth bass in eastern Lake Ontario.

The number of double-crested cormorants (Phalacrocorax auritus) in the upper St. Lawrence River has increased markedly since the early 1990s. In 1999, a binational study was initiated to examine the annual diet composition and fish consumption of cormorants at colonies in the upper river. Since 1999, 14,032 cormorant pellets, collected from May through September each year, have been examined from St. Lawrence River colonies to estimate fish consumption and determine temporal and spatial variation in diet. Seasonal variation in diet composition within a colony was low. Prior to 2006 yellow perch was the primary fish consumed by cormorants in the upper St. Lawrence River. Round goby were first observed in cormorant diets in 2003 and by 2006 were the main fish consumed at two of the three colonies. The time interval it took from the first appearance of round goby in the diet at a colony to when goby were the dominant prey species varied by island, ranging from two to five years. Daily fish consumption at each cormorant colony increased significantly from the pre-round goby to post-round goby period. The mean annual biomass of yellow perch consumed decreased significantly during the post-round goby period at the three colonies. Reduced consumption of yellow perch by cormorants may alleviate suspected localized impacts on perch near some of the larger river colonies.

Tungsten-tin mixed oxides at increasing Sn molar fraction (0.1, 0.3 and 0.5) were synthesized by solgel co-precipitation route. The prepared powders were characterized by electron microscopy (SEM and TEM), X-ray diffraction, specific surface area measurements (BET), UV-Vis-NIR and IR spectroscopies. It turned out that the mixed materials W-Sn(0.1) and W-Sn(0.3) form a solid solution with WO3 crystal structure without phase segregation, achieving the goal to reduce the WO3 grain growth with temperature. The prepared powders were deposited to produce gas sensors in form of thick films through screen-printing technology. The gas sensing measurements highlighted that the mixed oxide sensors offer a better response with respect to pure WO3, at the same time maintaining the characteristics of almost complete insensitivity to carbon monoxide and benzene.

Thick films of zinc oxide (ZnO) in form of nanospheres or hexagonal prisms and of tungsten-tin (W-Sn) mixed oxides at nominal Sn molar fraction (0.1, 0.3 and 0.5) were prepared. The functional materials were synthesized and characterized by SEM and TEM, X-ray diffraction, specific surface area measurements, UV-Vis-NIR and IR spectroscopies. The gas sensing measurements highlighted that ZnO is more performant in form of nanoprisms, while W-Sn sensors offer a better response towards NOx and ozone with respect to pure WO3.

New sensors for detecting gases at low concentration were successfully developed. Two metal oxide materials, zinc oxide and titanium dioxide, usually employed both in gas sensing as well as in photocatalytic application, were synthesized both through a traditional sol-gel method and an electrospinning technique. The corresponding thick films were considered with respect to the target gases (acetone for ZnO and carbon monoxide for TiO2) for comparing their functional properties.

This work was aimed at evaluating the efficiency of carbonate substitution in carbonated hydroxyapatites appropriately synthesized by a modified version of old hydrothermal methods, to obtain an increase of carbonate inside the lattice. The efficiency of carbonate substitution (linearly increasing until about 10% in weight) was determined by carbon elemental analysis, IR spectroscopy and thermal analysis and the results obtained were compared. For a structural characterization, the samples were analyzed by XRD and vibrational spectroscopy, which evidenced that at increasing carbonate content, the apatitic structure becomes progressively more amorphous. XRD and IR spectroscopy revealed that the samples were prevalently constituted of B-type carbonated hydroxyapatites. The Raman full width at half-maximum of the 962 cm −1 band (FWHM 962 ) and the I 1072 /I 962 intensity ratio can be good quantitative indexes of the carbonate content, as well as the IR E 1420 /E 565 extinction ratio. In thermogravimetric analysis (TG), the weight loss in the 400–1200 °C range was almost entirely attributed to carbonate decomposition. Both TG and IR results overestimated for most samples the carbonate content in comparison with elemental analysis, which is the most precise analytical method between those examined.

Geopolymers can be regarded as the amorphous counterpart or precursor of crystalline zeolites. Indeed, the final geopolymer structure consists of an amorphous network of SiO4 and AlO4- tetrahedral units connected by oxygens and charge-balanced by hydrated alkali cations, while zeolites are crystalline hydrated aluminosilicates with 3-dimensional structures. The negatively charged aluminosilicate lattices, due to Al in IV fold coordination, need to be balanced by extra-framework cations (generally Na+, K+ and Ca2+), endowing both the materials with ion exchange properties. Geopolymer-zeolite composites were produced mixing different geopolymer metakaolinbased matrices with a synthetic commercial zeolite. A potassium or sodium silicate activating solution was used for the geopolymerization process and the commercial zeolite Na13X was used as filler. The microstructure of a metakaolin-based geopolymer consists of nano-particulates separated by micro- and mesopores [1,2] therefore, the main goal of the study was to combine this porosity with the peculiar and defined microporosity of zeolite. Since zeolite is partially reactive in alkaline medium [3], the production process and the synthesis parameters were investigated to limit the reaction of the zeolite. Moreover, the requirement of supporting or shaping powdery zeolites is important for industrial applications and often add complexity and cost to the final product, hence the geopolymer binder results extremely useful to consolidate the zeolite powder. The production of these geopolymer-zeolite composites result in the formation of 3-dimensionally interconnected structures with highly accessible and distributed open pores, particularly suitable for catalysts, filters and sorbents. The selected composites were deeply characterized in term of microstructure, mineralogical composition, porosity and specific surface area, together with the ability to adsorb CO2, in order to highlight one of the possible functional properties of the new material, since zeolites, and in particular zeolite X are largely used for the CO2 gas adsorption [4].

Geopolymers are produced by reacting an aluminosilicate powder (metakaolins, blast furnace slags, fly ashes, pozzolana etc.) with an aqueous alkali hydroxide and/or alkali silicate solution [1], through an environmental friendly low temperature process. Furthermore, geopolymers can be regarded as the amorphous counterpart or precursor of crystalline zeolites [1]. Indeed, the final geopolymer structure consists of an amorphous network of SiO4 and AlO4- tetrahedral units connected by oxygens and charge-balanced by hydrated alkali cations, while zeolites are crystalline hydrated aluminosilicates with 3-dimensional structures. Both the materials have ion exchange properties, due to the presence of extra-framework cations (generally Na+, K+ and Ca2+) that balance the negatively charged aluminosilicate lattices caused by Al in IV fold coordination. Zeolites are extensively used as ion-exchangers, catalysts, molecular sieves and adsorbents thanks to the possibility to encapsulate a wide range of molecules in their structures formed by channels. Geopolymers, thanks to the mentioned similarities with zeolites, can be extended to a range of potential applications, similar to those of zeolites. This study reports the production and characterization of novel geopolymer-zeolite materials obtained adding a commercial synthetic zeolite X as filler to a metakaolin-based geopolymer matrix. Since the microstructure of a metakaolin-based geopolymer consists of nano-particulates separated by micro- and mesopores [1,2], the main goal was to combine the defined microporosity of zeolite with the mesoporosity of the geopolymer matrix, together with the possibility to consolidate the zeolite powder. In fact, the shaping of zeolite powders is important for industrial applications and often increases the complexity and the cost of the final product. The presence of a geopolymer binder results extremely useful to consolidate and form the zeolites also in complex and large shapes. 3-dimensionally structures with interconnected, distributed and highly accessible open pores were obtained and, because of zeolites, and in particular zeolite X, are largely used for the CO2 gas adsorption [3], the produced composites were tested in term of CO2 uptake, to highlight possible uses of the composites in adsorption or gas separation applications.

Six different ZnO nanomorphologies were synthesized trough wet chemical routes starting from a water solution of zinc nitrate hexahydrate, obtaining two types of morphologies: bidimensional nanocrystals and nanoparticles aggregates. Powders and films characterizations have been carried out by means of TG–DTA, SEM, and X-ray diffraction analysis. Finally, electrical measurements were performed with the aim to compare conductive properties of the thick films, surface barrier heights and gas sensing features, mainly versus acetone and other VOCs related to the breath gas analysis. Among the different morphologies tested, it turned out that the samples constituted by nanoparticle aggregates exhibited the best performances versus all gases, but especially toward acetone at sub-ppm level.

Geopolymer-zeolite composites were produced mixing different geopolymer matrices with a synthetic commercial zeolite. Metakaolin was selected as the main precursor for the geopolymer matrix, because it is the ideal material for the production of geopolymers due to the high reactivity and purity, compared to other starting raw materials as fly ashes and natural clays. A potassium or sodium silicate activating solution was used for the geopolymerization process and the commercial zeolite Na13X was used as filler. The microstructure of a metakaolin-based geopolymer consists of nano-particulates separated by micro- and mesopores [1,2]. Moreover, geopolymers can be regarded as the amorphous counterpart or precursor of crystalline zeolites. Indeed, the final geopolymer structure consists of an amorphous network of SiO4 and AlO4- tetrahedral units connected by oxygens and charge-balanced by hydrated alkali cations, while zeolites are crystalline hydrated aluminosilicates with 3-dimensional structures. The substitution of Al3+ for Si4+ results in negatively charged aluminosilicate lattice for both the materials, that needs to be balanced by extra-framework cations (generally Na+, K+ and Ca2+), resulting movable and exchangeable by other metal ions. Since zeolite is partially reactive in alkaline medium [3], the production process and the synthesis parameters were investigated to limit the reaction of the zeolite. In fact, the main goal of the study was to combine the peculiar and defined microporosity of zeolite with the meso- and macroporosity of the geopolymer matrix, together with the possibility to consolidate the zeolite powder. Actually, the requirement of supporting or shaping powdery zeolites is important for industrial applications and often the manufacturing and assembling of supports and zeolites add complexity and cost to the final product. Because of the high accessibility of pores, these porous composites with 3-dimensionally interconnected and distributed open pores, may be used as catalyst, filters and sorbents, furthermore, zeolites, and in particular zeolite X are largely used for the CO2 gas adsorption [4]. The selected composites were deeply characterized in term of microstructure, mineralogical composition, porosity and specific surface area, together with the ability to adsorb CO2, in order to highlight one of the possible functional properties of the new material.

The New York State Department of Environmental Conservation initiated a Double-crested Cormorant (Phalacrocorax auritus) control program in the eastern basin of Lake Ontario to mitigate cormorant impacts in 1999. Key objectives included improving the quality of Smallmouth Bass (Micropterus dolomieu) and other fisheries, restoring the structure and function of the warmwater fish community and reducing cormorant impacts to nesting habitats of other colonial waterbird species. In eight years of intensive control, cormorant numbers declined, with a corresponding reduction in estimated fish consumption. Diversity and numbers of co-occurring waterbirds either increased or have not been shown to be negatively impacted by management. Woody vegetation favorable to Black-crowned Night-Herons (Nycticorax nycticorax) has been maintained. A ca. 2.5-fold increase in the abundance of Smallmouth Bass abundance in assessment nets over the last seven years is a sign of improved recruitment to the fishery. Since t...

A two-year satellite telemetry study was initiated in May 2000 at a Double-crested Cormorant (Phalacrocorax auritus) breeding colony on Little Galloo Island (LGI) in eastern Lake Ontario, New York, USA, which is managed by egg-oiling. The objective was to describe cormorant (N = 26/year) movements, specifically during the period of reproductive management by egg-oiling and seasonally (breeding, migration and wintering). Egg-oiling at two-week intervals resulted in a hatch success on LGI of 5.7% for 2000 and 2001, combined. The majority (97%) of core use areas of marked cormorants contained LGI throughout three egg-oiling treatments (six weeks), and 71% still contained LGI by the end of the final (fourth) treatment (eight weeks). Of cormorants that moved during or after control activities, three remained in the vicinity of active breeding colonies for over three months. Cormorants initiated fall migration over a 16-week period ranging from 12 July to 29 October, with a mean departure date of 6 Se...

Alumina–zirconia composites with submicrometric grain size were surface modified with the purpose to induce bioactivity using several chemical treatments. Among them, a quick attack by phosphoric acid induced on Zirconia Toughned Alumina (80–20 wt%) the formation of apatite-like calcium phosphate phases after immersion in simulated body fluid, indicating bioactivity induction. Such a treatment does not reduce the strength, hardness and ageing properties of this ceramic material, making it a suitable method for biomedical applications. Surface properties, topography and microstructure of oxide ceramics are also discussed.

Calcium-aluminium-phosphate cements (CAPCs) for biomedical applications, mainly intended for applications in the dental field as non-resorbable fillers, were obtained by reacting Ca-aluminates compounds, i.e. CaO·Al(2)O(3) (CA) and CaO·2 Al(2)O(3) (CA(2)), with Al(H(2)PO(4))(3) aqueous solution. Hydroxyapatite was also introduced as a bioactive dispersed phase. Suitable elements like Sr and La were used to increase the radiopacity of the set yielded pastes towards X-ray wavelength used in clinical diagnostic radiographic equipments. La and Sr doped Ca-aluminates powders have been synthesized by solid state reaction at 1,400°C from a mixture of CaCO(3), Al(2)O(3), La(2)O(3) and SrCO(3). The characteristics of the obtained powders were analyzed and related to the starting compositions and synthesis procedures. The microstructure, setting time, radiopacity and compressive strength of the CAPCs have been investigated and discussed.

This work deals with the production of zirconium diboride (ZrB2)-based ultra-high-temperature ceramic porous bodies using different forming techniques with the aim to obtain a reduction in weight of the final components, to balance the high specific mass of ZrB2, useful especially in aerospace applications. A feasibility study for the production of ZrB2-based porous bodies from sponges and foams was carried out. A ZrB2 composition, containing silicon carbide as the secondary phase and silicon nitride (Si3N4) as a sintering aid, has been chosen with the aim to obtain lightweight devices by the replica method through slip casting of ceramic suspensions. Moreover, ZrB2 macroporous materials have been successfully produced using Si3N4 as a sintering aid and ovalbumin as a foaming agent. Sintering was performed at 2150°C with a dwell time of 120 min after a suitable process to pyrolize the organic templates and additives.

Dense and ultrafine alumina–zirconia composites (Al2O3–16 wt%ZrO2 and ZrO2–20 wt%Al2O3) are developed and characterized for load bearing prosthetic applications. The improvement of the ceramic/bone interface, namely of the ceramic bioactivity, is performed by a glass coating on the surface of the composites. A new composition is used to produce the glass powder, by melting at 1550 °C the mixture of oxide raw materials. The processing to obtain a homogeneous and adherent coating on the ceramic substrates is investigated: the optimal temperature for the glazing treatment is 1200 °C. The microstructure of the coating and of the ceramic/coating interface, the adhesion and some mechanical properties of the prepared glass and of the coating are analyzed. Besides, the in vitro bioactive responses, by incubation of osteoblast-like cells on the coated samples, are evaluated: positive results are confirmed after 24 h and 72 h.

In Part I, the processing, microstructure and mechanical properties of three silicon nitride-based ceramics were examined and their non-toxicity was demonstrated. In this Part II, some features critical to biomedical applications were investigated: (i) the wetting behaviour against aqueous media, including physiological solutions; (ii) the chemical stability in water and in physiological solutions; and (iii) the wear resistance, measured under experimental procedures that simulate the conditions typical of the hip joint prosthesis. The results confirmed that silicon nitride may serve as a biomaterial for bone substitution in load bearing prosthesis.

Eight biomedical glasses and three commercial glasses, as finely divided powders, were tested as initiators for the ring-opening polymerization of ϵ-caprolactone in bulk and in vacuo at 185°C. All the glass powders were able to initiate the polymerization, along with Pyrex, which was totally inert toward the monomer as the inner surface of a phial. The obtained polymers were examined with Fourier infrared transform spectroscopy and atomic force microscopy. The molecular weights were measured by viscometry in CHCl3. The presence of a fraction of the polymer firmly linked to the glass was quantitatively checked by the determination of the weight loss from the residues of the extraction with CHCl3 after calcination in a kiln at 945°C. The molecular weights and weight losses per unit surface were elaborated mathematically so that a possible correlation between these properties and the atomic compositions of the glasses could be better investigated. Two possible initiation mechanisms, induced by the hydroxyls present on the glass surface, were proposed: one for free poly(ϵ-caprolactone) and one for poly(ϵ-caprolactone) linked to the glass. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1579–1586, 2003

In elderly and osteoporotic patients an age-related loss of osteoinductivity could be the biological cause of implant failure regardless of the high quality of the implanted device. yttria stabilized tetragonal zirconia (YSTZ), either coated with the bioactive glass named RKKP bioglaze® (RKKP) or uncoated, was implanted in the distal femurs of sham-operated and ovariectomized female rats. Animals were sacrificed at 30 and 60 days. Histomorphometry and microhardness tests were performed to assess osteointegration rate as well as bone quality around the implants. Significant decreases (p < 0.0005) in trabecular bone volume, BV/TV (41%), trabecular bone surface BS/TV (33%), trabecular thickness Tb.Th (20%), and trabecular number Tb.N (32%), together with a significant increase in trabecular separation Tb.Sp (184%), were found for the osteopenic rats compared with the sham-operated rats. At both experimental times the RKKP coating ensured a better osteointegration rate with higher AI values than the uncoated YSTZ, even when osteopenic rats were used (48% at 30 days and 12% at 60 days). No differences were observed at the bone-biomaterial interfaces for either material when comparing sham-operated with osteopenic rats. The present results demonstrate that the RKKP bioactive glass used as a coating ensures a high osteointegration rate even in osteoporotic bone, which is already visible from postoperative day 30 and is still apparent on day 60. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 264–272, 2004

The production and the properties of lightweight composite panels, with expanded vermiculite as lightweight aggregate and geopolymer as binder, were investigated. Different compositions of the geopolymer binders (metakaolin or alumina-based) and two sizes of expanded vermiculite were tested. The produced composites were subjected to microstructural analyses, as well as to thermal and mechanical tests. Densities ranged between 700 and 900 kg/m3, while the average strength and thermal conductivity were about 2 MPa and 0.2 W/mK, respectively. Results show that lightweight composites can be produced with satisfactory density and mechanical and thermal properties compared with other materials used in building sector, such as plasterboard or cellular concrete. Keywords: Lightweight inorganic composites, Geopolymer, Expanded vermiculite, Thermal properties, Thermal conductivity

The biocompatibility and osseointegration of zir- conia (ZrO2), either coated with RKKP bioglaze or un- coated, were evaluated in vitro and in vivo. The in vitro test was performed in human osteoblasts, whereas maximal sen- sitization was performed in 23 Dunkin Hurtley guinea pigs. RKKP bioglaze-coated and uncoated (controls) ZrO2 cylin- ders were implanted in the distal femoral epiphyses of 14 Sprague-Dawley rats under general anesthesia, and animals were sacrificed at 30 and 60 days. Lactate dehydrogenase, alkaline phosphatase, and Thiazolyl Blue (MTT) were tested in vitro. A graded score was used for evaluating the results of the sensitization test. Histomorphometry and microhard- ness testing were performed to quantify the osseointegration rate, as well as bone quality around the implants. Neither in vitro cytotoxicity nor sensitization were observed. Histomor- phometry demonstrated that at 30 days, the affinity index was significantly higher in coated implants than in uncoated ones (p < 0.05); at 60 days, the behavior of coated implants was better than that of uncoated ones, but differences were not significant. Significant increases in bone microhardness were found at 1000 m from the interface area for both uncoated (p < 0.0005) and RKKP bioglaze-coated (p < 0.0005) ZrO2, and also within 200 m from the interface (p = 0.014) but only for coated ZrO2. These results suggest that RKKP bioglaze-coated ZrO2 permits biocompatible devices with improved osseointegration properties to be manufac- tured. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 282-289, 2002

Two bioactive silica-phosphate glasses, AP40 and RKKP, were compared in their behaviour in simulated biological environment. Their chemical composition is practically identical, except that RKKP contains small amounts of amphoteric network-former oxides Ta2O5 and La2O3 (composition in wt% for AP40: beta-Ca3(PO4)2 24.50, SiO2 44.30, CaO 18.60, Na2O 4.60, K2O 0.19, MgO 2.82, CaF2 4.99; RKKP: beta-Ca3(PO4)2 24.23, SiO2 43.82, CaO 18.40, Na2O 4.55, K2O 0.19, MgO 2.79, CaF2 4.94, Ta2O5 0.99, La2O3 0.09). Previous investigations showed a better performance in osteopenic bone for RKKP. To gain more insight into these differences in biological behaviour, the in vitro bioactivity of the glasses was studied by treatment with a continuously replenished Hanks' Balanced Salt Solution (HBSS). The glasses were examined before and after HBSS treatment for 20 and 40 days by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray Energy Dispersion (EDX), Raman and IR vibrational spectroscopies. Some slight but notable differences between the two glasses were observed after HBSS treatment. IR and EDX analyses showed that deposits formed on both glasses were composed of a calcium deficient carbonate-apatite; however, the layer formed on RKKP glass was found to be slightly more calcium deficient and thinner. EDX analysis evidenced the presence of a small percentage of F- ions only in the layers formed on the RKKP samples. The differences disclosed, although slight, can contribute to the understanding of the different biological behaviour previously observed.

The possibility of obtaining a good bioactive coating on biomedical devices made with zirconia ceramic was considered. Yttria partially stabilized zirconia was used to produce suitable substrates. The obtained adhesion was good (66±13 MPa) and encouraging for biomedical applications. Small microcrystals formed inside and on the surface of the glass layer. These microcrystals transformed the glass into a glass-ceramic. An accurate investigation of the nature of this microcrystal formation was carried out to verify its compatibility with the planned biomedical applications. © 1998 Chapman & Hall

This work was aimed at evaluating the efficiency of carbonate substitution in carbonated hydroxyapatites appropriately synthesized by a modified version of old hydrothermal methods, to obtain an increase of carbonate inside the lattice. The efficiency of carbonate substitution (linearly increasing until about 10% in weight) was determined by carbon elemental analysis, IR spectroscopy and thermal analysis and the results obtained were compared. For a structural characterization, the samples were analyzed by XRD and vibrational spectroscopy, which evidenced that at increasing carbonate content, the apatitic structure becomes progressively more amorphous. XRD and IR spectroscopy revealed that the samples were prevalently constituted of B-type carbonated hydroxyapatites. The Raman full width at half-maximum of the 962 cm−1 band (FWHM962) and the I1072/I962 intensity ratio can be good quantitative indexes of the carbonate content, as well as the IR E1420/E565 extinction ratio. In thermogravimetric analysis (TG), the weight loss in the 400–1200 °C range was almost entirely attributed to carbonate decomposition. Both TG and IR results overestimated for most samples the carbonate content in comparison with elemental analysis, which is the most precise analytical method between those examined.

Research directed to innovative solutions for the national electric system are carried out in many CNR Institutes. In this project, many CNR research groups collaborated to develop a small cogeneration system, environmentally and economically sustainable, which could be integrated into the National grid. For the CHP cogenerator, we have opted for the internal combustion engine that is one solution with highest possibilities of success, thanks to the maturity and reliability of these systems. A prototype engine (15-25 kWe) has been designed deriving from an automotive engine of the latest generation, fuelled by very robust but low cost industrial natural gas. The CHP generator has been improved with unconventional technology and plant solutions that allow increasing the life service, heat and electrical performance, reducing noise and size. More in detail, the studies have been devoted to the w ear reduction through the development of special nanolubricants and of protective hard coatings; to the heat recover by means of innovative metallic foam heat exchangers; to improve the heat and acoustic insulation by means of low-cost geopolymers. The work is funded by the Project MATEC in the framework of a Research Program for the National Electric System.

Different methods of direct and indirect foaming were applied to produce porous ceramics based on ZrB2 and/or SiC. Clot forming was used to produce highly porous ZrB2 ceramics by exploiting the foaming property of ovalbumin and its ability to thicken after heating around 80°C. SiC foams were developed by in situ foam formation in alkaline environment using a low temperature process such as a chemical consolidation. An alkali aluminosilicates binder was used. The foaming agent was metallic silicon iimpurity in SiC powder. Replica method was used to produce ZrB2- SiC porous composite. Polyurethane templates generated empty ceramic struts that decrease mechanical performances. Foams from PU showed very low compressive strength: 0.7 MPa with porosity >=85 vol% and 0.3 MPa with porosity >=88 vol%. Thank to hydrophilic surfaces, cellulose or natural sea sponges were permeated by the suspension, yielding open cells with dense wall structure after sintering, thus increasing mechanical strength up to 4.8 MPa. Finally, the possibility to shape into graded porous structures by freeze casting was investigated on ZrB2 and ZrB2-SiC composites. The total porosity was about 63-64 vol % and hierarchical architectures with anisotropic porosity were realized, which showed porosity formed by mainly unidirectional channels separated by ceramic plates. The compressive strength was improved compared to sponge-templated foams.

Lymphoma was one of the first cancers curable by radiotherapy and/or chemotherapy. However the increased risk of second malignancies in lymphoma survivors appeared to be the price of success of modern treatment modalities. In particular, breast cancer has been a major concern among women irradiated for lymphoma at a young age. There are several reports of breast cancer after Hodgkin's lymphoma, but few after non-Hodgkin's lymphoma. Owing to the particularity of this condition and the difficulties in its diagnosis and treatment, we wish to report the case of ductal infiltrant carcinoma of the breast in a young woman survived to a non-Hodgkin's lymphoma. Women who are survivors of pediatric lymphoma have a significantly increased risk of subsequent breast cancer compared with the general population and are at a high risk of developing bilateral disease within a short interval. Several studies have shown that the relative risk for secondary breast cancer becomes significantly increased between 5 and 9 years and rises dramatically between 15 and 19 years after lymphoma treatment. Screening programs to detect breast cancer should be initiated early after Hodgkin's and non-Hodgkin's lymphomas. Screening have to include breast self examinations every month, clinical breast examinations every 6 months, and mammography every 2-3 years. The patients should start breast self-examination at puberty. In these high-risk patients, "aggressive" biopsy is appropriate for suspicious lesions.

The interactions of Type I acid soluble collagen (Col) with both carbonate-free hydroxyapatite (HA(1100)) and carbonate-rich one (CHA) were investigated. The aim was to ascertain whether the increase of bone CO(3) (2-) with ageing could relate to the disease known as osteoporosis. HA(1100)-Col and CHA-Col composites with various ratios were prepared and examined. Scanning electron microscopy and differential scanning calorimetry showed a stronger adhesion of the Col matrix to the granules of HA(1100) than to those of CHA. FT-IR spectroscopy showed that with HA(1100) both multiple hydrogen bonds of Col peptide -NH groups with HA PO(4) (3-), and electrochemical interactions between Col peptide -C=O groups and HA Ca(2+) were present. In the presence of CO(3) (2-), the interactions between -NH and phosphate were diminished, and Ca(2+) interacted more strongly with CO(3) (2-) than with peptide -C=O, so causing a separation between the two components of the bone extra-cellular matrix. The results obtained strengthen the hypothesis that the substitution of PO(4) (3-) ions by CO(3) (2-) ions in the HA lattice might be a significant component of osteoporosis, although further investigation is needed.

Although in several EU Member States many public interventions have been running for the prevention and/or management of obesity and other nutrition-related health conditions, few have yet been formally evaluated. The multidisciplinary team of the EATWELL project will gather benchmark data on healthy eating interventions in EU Member States and review existing information on the effectiveness of interventions using a three-stage procedure (i) Assessment of the intervention's impact on consumer attitudes, consumer behaviour and diets; (ii) The impact of the change in diets on obesity and health and (iii) The value attached by society to these changes, measured in life years gained, cost savings and quality-adjusted life years. Where evaluations have been inadequate, EATWELL will gather secondary data and analyse them with a multidisciplinary approach incorporating models from the psychology and economics disciplines. Particular attention will be paid to lessons that can be learned from private sector that are transferable to the healthy eating campaigns in the public sector. Through consumer surveys and workshops with other stakeholders, EATWELL will assess the acceptability of the range of potential interventions. Armed with scientific quantitative evaluations of policy interventions and their acceptability to stakeholders, EATWELL expects to recommend more appropriate interventions for Member States and the EU, providing a one-stop guide to methods and measures in interventions evaluation, and outline data collection priorities for the future.

patients with body dysmorphic disorder often go to the plastic surgeon to correct what they consider a physical deformity or defect, although their appearance falls within normal aesthetic standards. The aim of our study was to evaluate the real need for aesthetic treatments in such patients.we included patients who practised an intense sport activity and believed they had body deformities ascribable to their sport activity. We evaluated whether the deformities described by the patients were real or exaggerated. The patients who did have a deformity underwent surgery to correct it; their level of satisfaction was evaluated at a 6-month follow-up examination. The patients with subjective deformities underwent a psychiatric examination.we enrolled 51 patients who practised an intense sport activity and reported body deformities. Forty-one of these patients were found to have a body deformity upon examination and underwent surgery. Surgery was considered to be unnecessary in the remaining 10 patients. Thirty-two of the 41 patients who did undergo were highly satisfied with the outcome.the plastic surgeon often sees patients with minor body deformities that do not require treatment but are a major cause of psychological disorders. A thorough psychiatric examination is necessary in such patients to rule out psychiatric diseases. The plastic surgeon should make every effort to identify patients with subjective body dysmorphic disorder to avoid the negative consequences due to the patient's insatisfaction for the outcome of surgery.

Purpose To compare articulation and speech rates of school-aged children who do and do not stutter across sentence priming, structured conversation, and narration tasks and to determine factors that predict children's speech and articulation rates. Method 34 children who stutter (CWS) and 34 age- and gender-matched children who do not stutter (CWNS) were divided into younger (M age = 6;10) and older (M age = 9;6) subgroups. Speech samples were elicited using the Modeled Sentences, Structured Conversation, and Narration tasks from an experimental version of the Test of Childhood Stuttering ( Gillam, Logan, & Pearson, 2009 ). Speech rates (based on both fluent and disfluent utterances), articulation rates (based on only fluent utterances), disfluency frequency, and utterance length were compared across groups and tasks. Results CWNS had faster speech rates than CWS. Older children had faster speech rates than younger children during Modeled Sentences, and their Modeled Sentences speech rates were faster than their Structured Conversation and Narration speech rates. Disfluency frequency predicted speech rate better than age or utterance length for CWS and CWNS. Speech rate was negatively correlated with stuttering severity for CWS. Articulation rates for CWNS and CWS were not significantly different; however, older children had faster articulation rates than younger children, and articulation rates for both age groups were fastest during Modeled Sentences. Conclusions Results provide age-based reference data for the speech and articulation rates of school-aged CWS and CWNS on three TOCS tasks and offer insight into the relative contributions of age, disfluency frequency, and utterance length to children's rate performance. Learning outcomes After reading this paper readers should be able to: (1) summarize the main findings from past studies of children's speech rate and articulation rate; (2) describe how school-aged children who stutter compare to age-matched children who do not stutter with regard to speech rate and articulation rate; (3) explain the extent to which age, speaking task, disfluency frequency, and utterance length affect children's rate performance; (4) discuss the advantages and disadvantages of various approaches to rate measurement.