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This paper presents an overview of the ROSSINI project, illustrating its general objectives and how it places itself within the overall field of seismic risk-aware navigation systems. In particular, it describes the use of a sensor array for the integrated risk-aware navigation in industrial plants at risk of NaTech accidents. The integration of structural and environmental risks estimated and measured in different ways is presented as part of an integrated risk identification and evaluation (RIE) module. This module will be used along with a series of logic to combine and map the possible risks spatially within an industrial plant’s layout. It is seen how this information can then be used to not only compute the safest path to safety for a worker located within such a plant but also how mobile communications can be used to aid and guide them in different scenarios. All of this stems from the use of a sensor array network in a relatively novel way within this particular context. The paper discusses the progress to date and presents the ongoing results of a pilot case study application of the system to an industrial plant facility in Italy.

Industrial plants are quite susceptible to NaTech disasters during earthquakes caused by damage to structural and non-structural components and the potential release of toxic materials. To mitigate and manage this risk, the ROSSINI project was initiated and its results are described here for what concerns industrial plant worker safety and their risk-based navigation in emergency situations. The project includes a data acquisition system consisting of a data acquisition board and an array of different sensor technologies, which process the seismic event and other meteorological information before passing them as inputs towards the risk identification and evaluation (RIE) modules. Here, the risks associated with structural and non-structural damage and health risks associated with the release of harmful substances are estimated and combined to form a navigable risk map. This map is used within a purpose-built risk-based navigation application for the safe egress of workers from an industrial plant. To demonstrate the implementation of this system, two case-study industrial plant layouts consisting of buildings, non-structural components, liquid storage tanks, piping systems, and chemical storage vessels, were devised. This paper describes the project’s implementation in these contexts and illustrates the results via several example scenarios.

This study aims to develop a restorative material having such mechanical and adhesive properties that it can be used both as a reconstruction material and as a luting cement. The experimental core build-up composite (CBC) was derived from a self-adhesive cement by the modification of its chemical formula, requiring the use of dedicated dentin and ceramic primers. The adhesive properties to zirconia and dentin were analyzed with a micro-Shear Bond Strength test (mSBS). The mechanical properties were analyzed by a flexural strength test. The results were compared with those obtained for other commercially available cements and core build-up materials, both before and after addition of 2 wt.% fluorographene. The CBC obtained average values in the mSBS of 49.7 ± 4.74 MPa for zirconia and 32.2 ± 4.9 MPa for dentin, as well as values of 110.9 ± 9.3 MPa for flexural strength and 6170.8 ± 703.2 MPa for Young’s modulus. The addition of fluorographene, while increasing the Young’s modulus of the core build-up composite by 10%, did not improve the adhesive capabilities of the primers and cement on either zirconia or dentin. The CBC showed adhesive and mechanical properties adequate both for a restoration material and a luting cement. The addition of 2 wt.% fluorographene was shown to interfere with the polymerization reaction of the material, suggesting the need for further studies.

The collapse of the Polcevera bridge in Italy represents a serious event which seems to be a direct result of cumulated local damages due to the aggressive environment of the construction site. Recently, evidence of corrosion of both ordinary and post-tension steel reinforcements were detected, in addition to concrete carbonation. Such phenomena generally lead to an increase in the deformation of all the elements of the bridge structure, which start to increase in time, leading to a progressive deterioration of the overall system. As a consequence, a proper structural monitoring layout would provide an extremely useful tool, for a correct plan of maintenance for all the elements of the considered infrastructure. In this work, strategies for the definition of structural health monitoring systems for bridges are discussed, from both software and hardware points of view. More specifically, a Cloud computing interface is considered, to make recorded data available for further analyses and post-processing procedures. The presented definition of the monitoring architecture could lead to the proper maintenance of all the structural elements, preventing the unexpected collapse of the structure.

To report in literature the first case of fatal multi-organ embolization of ureteral stones fragments during laser lithotripsy. A tetraplegic 43-year-old woman was admitted to the hospital to undergo laser lithotripsy because of bilateral ureteral stones and right ureteral infected stent. During the removal of the right ureteral stent, the patient developed a sudden severe bradycardia followed by a reduction in the arterial oxygen saturation. In spite of a rapid and intensive medical intervention, the clinical picture did not improve; the woman was therefore transferred to the nearest Emergency Room where she was rescued but a cardiocirculatory arrest occurred. A claim of alleged medical malpractice was brought against the urologists. A complete autopsy was performed 8 days after death. The diagnosis was determined by the microscopic findings: they have unequivocally shown a massive embolization of calculus fragments in the lungs and in the heart. In the light of all these findings, the cause of death was attributable to a disseminated intravascular coagulation due to this unforeseeable embolization of calcified amorphous material. Embolization of calculus fragments represents an important challenge because it is extremely unpredictable. Indeed, a prompt diagnosis of non-thrombotic pulmonary embolism, during the urologic procedure, is extremely difficult because the condition presents with no specific clinical signs: this life-threatening pathology is often underestimated. For this reason, the autopsy and the subsequent histopathological examination are indispensable in order to prove lethal embolization: microscopic findings play a key role in the final diagnosis of death.

Objective: The simple observation of breathing rate (BR) remains the first and often the most sensitive marker of acute respiratory dysfunction. In fact, there are evidences that drastic changes in BR are a predictive indicator of adverse events (i.e. cardiac arrest). The aim of this study is to develop a camera-based technology that may provide near-continuously estimation of BR considering the effect of respiration on videoPPG (vPPG). Approach: The technology has been tested in two different experimental settings, including controlled BR and more challenging scenarios with spontaneous breathing pattern. Video data were processed offline to derive the vPPG signal. The method derives respiration from beat-to-beat PPG rate and morphology changes in amplitude and width driven by the physiological relationships between vPPG and respiration. Moreover, respiratory-induced head movements were used as additional source of information for the vPPG system. A combination of these methods has been exploited to estimate the respiratory rate every 10 second. Main Results: According to the results, respiratory frequencies in the central range (0.2-0.4 Hz) may be estimated using vPPG system with low relative error, eR < 2 % and interquartile range of order IQR < 5 %. However, the vPPG system showed a drop in performance at respiratory range boundaries, around 0.1 Hz and 0.5 Hz. Significance: This camera-based technology can be used as ubiquitous BR monitoring system. However, vPPG-based systems should consider the effect of the BR in the estimation, mainly in applications where respiratory rate is out of the range 0.2-0.4 Hz.

Purpose Quantitative and qualitative changes of skeletal muscle are typical and early findings in trauma patients, being possibly associated with functional impairment. Early assessment of muscle changes—as evaluated by muscle ultrasonography—could yield important information about patient’s outcome. Methods In this prospective observational study, we used ultrasonography to evaluate the morphological changes of rectus femoris (RF) and anterior tibialis (AT) muscles in a group of young, previously healthy trauma patients on enteral feeding. Results We studied 38 severely injured patients (median Injury Severity Score = 34; median age = 40 y.o.) over the course of the ICU stay up to 3 weeks after trauma. We found a progressive loss of muscle mass from day 0 to day 20, that was more relevant for the RF (45%) than for the AT (22%); this was accompanied by an increase in echogenicity (up to 2.5 by the Heckmatt Scale, where normal echogenicity = 1), which is an indicator of myofibers depletion. Conclusions Ultrasound evaluation of skeletal muscles is inexpensive, noninvasive, simple and easily repeatable. By this method, we were able to quantify the morphological changes of skeletal muscle in trauma patients. Further studies may rely on this technicque to evaluate the impact of different therapeutic strategies on muscle wasting.

An experimental setup exploiting grating-coupled surface plasmon resonance (GCSPR) technique based on polarization modulation in conical mounting is presented for the first time. A metallic grating is azimuthally rotated in order to support excitation of surface plasmon polaritons (SPPs) with enhanced sensitivity. In correspondence of SPP resonance, a polarization scan of the incident light is performed and reflectivity is collected. Output signal exhibits harmonic dependence on polarization and the phase term is exploited as a parameter for sensing analysis. Since the sensing configuration is kept fixed during the analysis and the only degree of freedom is represented by the incident polarization, the mechanical complexity of this SPR system is significantly reduced with respect to other configurations. Moreover the setup assures competitive performance in refractive index sensitivity and resolution. The assembled prototype is tested for fluid analysis with an embedded glass/PDMS microfluidic cell fabricated by soft-lithography procedure. A model biorecognition assay based on avidin/biotin reaction was considered in order to test the detection performance of the presented setup. (C) 2013 Elsevier B.V. All rights reserved.

Azimuthally controlled grating-coupling surface plasmon resonance (φ ≠ 0° GC-SPR) is known to exhibit refractive index sensitivity (SRI) up to one order of magnitude higher with respect to classic φ = 0° GC-SPR. Here, grated gold surfaces (period of 500 nm and amplitude of 40 nm) were covered with different amounts of thiol-poly(ethylene oxide) (PEO, Mw 5 kDa) through a 24 h functionalization process using polymer solutions at increasing concentration (from 500 nM to 2.5 mM). The GC-SPR output signal generated by each PEO layer was measured in both null and rotated configuration. The number of PEO molecules adsorbed onto each surface (cm−2) and the corresponding molecular surface densities (σ [ng/cm2]) were calculated from the angle shifts collected after PEO film formation, by combining the model shown by Jung and the theory of PEO layer formation. In the end, we obtained a calibration curve that correlates the amount of PEO tethered onto the surface with the SPR measurement output signal, that will be useful for future reference. At the PEO surface saturation condition (PEO σ = 592 ng/cm2, obtained using PEO concentration ≥2 mM), a SRI of 603°/RIU was reached (φ = 45°), which is ≈10-fold higher than what obtained through the classic GC-SPR (φ = 0°). This enhanced instrumental sensitivity allowed detecting tiny amounts of molecules adsorbed onto the surface (3.1 ng vs 59.7 ng of classic φ = 0° GC-SPR), a property that is extremely valuable for the application of SPR sensing to quantitative determinations.

Nanosphere lithography coupled with reactive ion etching has been used to synthesize hexagonal ordered arrays of Au-Ag bimetallic semi-nanoshells to be used as plasmonic biosensors. The degree of lateral interaction between adjacent semi-nanoshells can be controlled by tailoring the reactive ion etching time in order to boost the global plasmonic properties through the formation of near-field hot-spots, which in turn can improve the sensitivity of the biosensors. To test the efficiency of the proposed system as a biosensor, we used an established protocol for the detection of biomolecules (local sensitivity), based on the receptor-ligand approach and using the biotin-streptavidin model system. We also tested the sensitivity to a homogeneous change in the refractive index of the buffer over the sensor (bulk sensitivity). Comparing the obtained results to those of an array of nanoprisms, chosen as a benchmark, significantly higher performances both in local and bulk sensitivities have been found, in agreement with electrodynamics simulations based on finite-element methods.

The Avidin-Nucleic-Acids-Nano-Assembly (ANANAS) is a kind of soft poly avidin nanoparticle originating from the high affinity interaction between avidin and the nucleic acids. In this work we investigated the possibility of transforming ANANAS cores into stoichiometrically controlled multifunctional nanoparticles through a "one-pot" procedure, and we measured in a quantitative way their ability to work as reagents for enhanced immunodiagnostic detection. Initially, we measured the ANANAS loading capability for biotinylated proteins of different nature. About 200 molecules of biotin-horseradish-peroxidase (40KDa b-HRP) and 60 molecules of biotin-immunoglobulin-G (150KDa b-IgG) could be accommodated onto each nanoparticle, showing that steric limitations dictate the number of loadable entities. Stoichiometrically controlled functional assemblies were generated by mixing core particles with subsaturating amounts of b-HRP and b-IgG. When applied as detection reagents in an Enzyme-Linked-ImmunoSorbed-Assay (ELISA), these assemblies were up to two-orders of magnitude more sensitive than commercial HRP-based reagents. Assemblies of different composition displayed different efficacy, indicating that the system functionality can be fine-tuned. Within-assay variability (CV%), measured to assess if the assembly procedure is reproducible, was within 10%. Stability experiments demonstrated that the functionalyzed assemblies are stable in solution for more than one week. In principle, any biotinylated function can be loaded onto the core particle, whose high loading capacity and tunability may open the way toward further application in biomedicine.

The synthesis and characterization of imprinted polymer composite membranes and use of the membranes for depleting riboflavine from beer are hereby reported. The membranes were prepared by phase inversion of a suspension of imprinted polymer particles, which had previously been shown to exhibit selective recognition of vitamin B2 in aqueous media in a solution of poly-methylmethacrylate and polyethylenglycol in acetone. Membranes with different loads of imprinted particles were prepared and characterized by scanning electron microscopy, Fourier-transform infrared chemical imaging and permeability measurements. Subsequently they were tested in both static and dynamic partitioning experiments concerning their ability to bind riboflavine versus other competing solutes such as lumichrome and uridine. The membranes exhibited a pronounced selectivity for riboflavine and were capable of partially depleting nearly 80% of the vitamin from beer. Meanwhile, a membrane prepared identically using nonimprinted particles resulted in a maximum removal of nearly 50%, however, with low selectivity. PRACTICAL APPLICATIONS Membranes incorporating molecularly imprinted polymer particles is a new tool for food processing allowing the traceless removal of preselected substances, e.g., flavors, spoilage agents or impurities. As suggested by the results presented in this contribution, such membranes could potentially find use in the brewing industry for selective depletion of riboflavine thus leading to enhanced beer stability.

The bioartificial chitosan–poly(vinyl alcohol) blends were toughened by means of a dehydrothermal treatment (DHT), to facilitate the formation of hydrogen bonds between the macromolecules. The materials were characterized by stress–strain test, contact angle measurement, spotlight Fourier transform infrared spectroscopy and chemical imaging, weight loss in water, swelling in water vapor saturated atmosphere, Alamar blue test to evaluate the indirect cytotoxicity, and the diffusive permeation, through membranes made with the blends, of D(+)glucose, vitamin B12, and bovine serum albumin. The results were compared with those of the blends crosslinked by glutaraldehyde (GTA). The Young's modulus ranges between 10.56 and 16.12 MPa, and it is higher for the blends subjected to DHT than for those crosslinked by GTA, a fact explainable by the elasticity of the latter, due to the flexible bridges connecting the different chains. The contact angles indicate a scarce wettability, and then a scarce hydrophilicity, which is confirmed by the chemical imaging of the surfaces, made in the total reflection (microATR) mode, of the films toughened by DHT: the ν(OH) band in the 4000–3000 cm-1 is nearly absent in all the regions of the maps. Moreover, the correlation maps indicate a homogeneous distribution of the two components within the blends. The weight loss in water is generally less than 15%, and increases with the content of the ionizable macromolecule chitosan in the blends, a trend shown also by the swelling after exposure to water vapors. Alamar blue test shows that none of the eluates, after being in contact with the materials up to seven days, appears cytotoxic toward murine fibroblasts. As concerning the diffusive permeation, it appears good for D(+)glucose, quite good for vitamin B12, and scarce for bovine serum albumin. In conclusion, the chitosan–poly(vinyl alcohol) blends studied appear to be suitable for their use as biomaterials.

Polymeric scaffolds, in the form of porous membranes, modified to favour cell adhesion and proliferation on their surface, were prepared using an innovative technique of functionalization, based on molecularly imprinting technology. A series of membranes based on poly-ε-caprolactone were obtained through phase inversion using different solvents and non-solvents. Diffusion tests showed that prepared membranes exhibited a good permeability towards important nutrients such as folic acid and glucose. The ability of membranes, modified with imprinted nanoparticles, to facilitate cell adhesion and proliferation was evaluated by cell culture method using murine fibroblast cell line. SEM analysis at 72 h after seeding revealed an improved cell distribution on the surface of the membranes functionalized by deposition of molecularly imprinted nanoparticles.

In the present work the synthesis and the chemical and thermal characterization of poly(methyl methacrylate-co-butyl methacrylate) copolymer, in three different macromolecular compositions, are reported. The aim of the present work was the identification of a standard method to obtain copolymers with controlled macromolecular composition, molecular weights and particle size distribution, together with the identification of the effect of the macromolecular composition on the material properties. A monomer-starved seeded semi-batch emulsion reaction was carried out and optimized, monitoring the kinetic of the copolymerization through the evaluation of residual monomer amounts. Then, an evaluation of the macromolecular composition was performed by Fourier transform infrared spectroscopy analysis. Molecular weight, molecular weight distribution, latex characteristics and thermal behaviour were also investigated.

Bioartificial biodegradable materials were prepared mixing chitosan (CHI) and poly(vinyl alcohol) (PVA), then manufactured as films, and finally cross-linked with glutaraldehyde (GTA), both in the absence and in the presence of the edible hexa-alcohol sorbitol (SOR), as a plasticizer. The release of the components into water was tested by high performance liquid chromatography (HPLC); no release of CHI and scarce release of PVA were found. The water uptake was tested by measuring the swelling of the materials, after incubating them for 20 h in an atmosphere saturated with water vapor at 37°C. The swelling percentage increases with increasing CHI content in the blends, although it is the less hydrophilic polymer. This behavior was attributed to the difficulty of water to diffuse through the crystalline PVA structure, which is partially altered in the blends. The addition of SOR enhances the water sorption, as expected. The biodegradability of the materials was tested using the specific enzyme chitosanase, and was found to depend on the blend composition, as well as to be enhanced by the addition of SOR. The initial degradation rates were calculated; the maximum rates were found when the CHI to PVA ratio was 80:20 for all systems. The results of the enzymatic degradation generally agree with those of the swelling. The cross-linked blends were also tested as drug-delivery systems. The drugs chosen were the vitamin L-ascorbic acid (AsA) and the anti-cancer drug paclitaxel (PTX). The effective diffusion coefficients, D eff , were evaluated for the release of both the drugs from each material. Those of AsA are greater, of many powers of ten, than those of PTX, owing mainly to the hydrophilic nature of the first drug and to the hydrophobic of the second one. In conclusion, these materials seem available for biomedical use.

The preparation of novel polymeric systems through Molecular Imprinting Technology (MIT) for potential application in extracorporeal blood purification is described. Membranes based on poly(ethylene‐co‐vinyl alcohol) material, produced through a phase inversion method, were modified introducing in their structure specific binding sites for lipid and/or protein molecules. Membranes prepared are intended to selectively remove low density lipoproteins and cholesterol (LDL) from the plasma, by using interactions at a molecular level, between the molecularly imprinted membrane and specific target molecules, created during the preparation procedure. The binding performances of membranes and their potentiality as adsorbents for two different model target compounds, a phospholipid (phosphotidylcholine, PC) and a protein (α‐amylase enzyme) were investigated, showing improved adsorption capacity with respect to unmodified control membranes. In addition, molecularly imprinted poly(ethylene‐co‐vinyl alcohol)...

Modulation of inflammatory and immune response to critical illness has been the goal of much research in the last decade and a variety of drugs and nutrients (so called "immunonutrients") have been tested in experimental models with promising results. Though, in the clinical setting of intensive care, their efficacy have been inconsistently proven, most likely because the effects of each drug may vary in relation to the timing, the dose, the route of administration, the interaction with other nutrients, the severity of illness and many other factors. Though the early studies of the beginning of this century (2000-2009) have shown some clinical benefits, recent multicenter trials (2011-2015) have failed to prove a consistent benefit of immunonutrition in terms of mortality or other clinical endpoints. Reviewing the latest evidence-based documents on this subject (multicenter trials, systematic reviews, meta-analyses and international guidelines), there is no convincing evidence that immunonutrients may be beneficial in the critically ill. Considering that these substances invariably increase the costs of health care and may be unsafe or even harmful in some subgroups, particularly in septic patients, we conclude that routine administration of immune-nutrients (glutamine, arginine, omega-3 fatty acids, selenium, etc.) cannot be currently recommended in the critically ill.

Membranes with molecular recognition properties were obtained by coagulation in the presence of compounds of biotechnological interest or by modification of non-imprinted membranes with the introduction of imprinted nanoparticles obtained by polymerisation of a monomer(s) in the presence of a stamp molecule (template). The functional binding performances in aqueous medium towards template molecules (uric acid, theophylline, caffeine or proteins) were investigated. Membranes of acrylonitrile-acrylic acid copolymer imprinted with uric acid showed satisfactory recognition capacity and selectivity towards the template (rebinding of uric acid resulted 2.4 times higher than that of theophylline). Porous supports of ethylene-co-vinyl alcohol-dextran blends were obtained using α-amylase as template and selective properties were confirmed by a rebinding of the stamp molecule 1.96 times higher than that of albumin. In some cases, recognition properties of methylmethacrylate-co-acrylic acid membranes were enhanced by loading on the surface, or inside the membrane, imprinted cross-linked methylmethacrylate-methacrylic acid nanospheres. The different membranes realised are promising solutions for filtration or adsorption applications in biomedical field or for other biotechnological uses where biomimetic behaviour in water media is requested.

We investigated the influence of various physicochemical parameters on the morphology and time-porosity formation of membranes composed of ethylene-vinyl alcohol, starch, and alpha-amylase. In particular, we determined that (1) it is possible to obtain a membrane with desired porosity by phase inversion in an appropriate water-ethanol mixture and (2) the enzymatic bioerosion is controlled by the amount of alpha-amylase present in the blend. Although no experiments involving drugs were carried out, the delivery properties of the film were determined by measuring the Darcy permeability, the effective diffusivity, and the mean reaction rate of the membranes, relating them to the modality of membrane preparation, the amount of enzyme present within the membrane, and the incubation time of the samples in a buffer solution. Simple theoretical models of the delivery properties of the membranes were developed, leading to predictions that were in good agreement with the experimental results.

Molecularly imprinted membranes imprinted for a large-molecular-weight protein were realised using a blend of natural and synthetic polymers. Bioartificial membranes of synthetic (poly(ethylene-co-vinyl alcohol)-EVAL, Clarene) and biological (Dextran) polymers, molecularly imprinted with alpha-amylase as the template, were prepared and investigated. Dimethyl sulfoxide (DMSO) solutions of the alpha-amylase template, Clarene and Dextran were mixed under stirring in the desired proportions and dipped in DMSO (solvent)/water (non solvent) mixture, to obtain the phase separation. The release of Clarene, Dextran and alpha-amylase in the inversion baths was quantified by spectrophotometric methods and final composition of membranes was established. To study the interactions between the polymer components and between polymeric materials and the template, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were carried out. Results indicated that stable and continuous bioartificial membranes of Clarene and Dextran can be obtained, whereby calorimetric analysis suggested the presence of high interaction between alpha-amylase and the Clarene component.

Cross-linked poly(methylmethacrylate-co-methacrylic acid) nanospheres were imprinted with theophylline through template radical polymerisation in diluted acetonitrile solution. This study will focus on the effect of functional monomer nature used (methylmethacrylate and/or methacrylic acid) in the recognition and in the release of template in order to develop a material with combined properties of drug delivery and rebinding for clinical applications. After template extraction the nanospheres showed satisfactory recognition properties (up to 1 mg template/g of polymer). Moreover polymers prepared selectively removed theophylline with a theophylline rebinding of 5.1 times higher than that of caffeine, a compound of similar structure. Drug release properties were also satisfactory (up to 95% of loaded theophylline in 7 days).

Loss of mass and function of skeletal muscle during critical illness is associated with poor clinical outcome, reduced ventilator-free days, increased length of ICU stay, increased mortality, high costs of health care, and delay of rehabilitation [1]. The magnitude of muscle impairment correlates with the severity of the illness, the entity of the inflammation, and the appropriateness of nutritional support [2, 3]. Recent papers have advocated the use of ultrasound evaluation of skeletal muscle [2, 4, 5] to get information about its thickness and structural changes, which can be related to the degree of myopathy and to the final functional outcome [5]. We are investigating the morphological changes of skeletal muscle in trauma patients during their stay in our ICU, by ultrasound evaluation of the rectus femuris (RF) and anterior tibialis (AT) muscles (transverse scan 15 cm above the patella and 5 cm below the fibular head, respectively), on day 0 (within 24 h after admission to ICU) and on day 21. We adopted a 5–7 MHz linear transducer and a well-defined setting for all patients (overall gain 67 %; time gain compensation in neutral position; focal zone set in the middle of the muscle). Muscle echogenicity is rated according to Heckmatt’s scale [6], which is a semiquantitative, four-rank score, the higher rank (D) corresponding to reduced visualization of bone surface and thus to a more severe degree of muscle fibrosis. In this preliminary study, we evaluated six severe trauma patients: three women/three men; age range 44–61 years; body mass index ranging from 23.1 to 28.2; injury severity score 29–52; all but one had brain injury, with Glasgow Coma Scale at admission ranging from 3 to 11; ICU stay was 25–52 days and survival was 100 %. In all patients, we found a progressive decrease in the muscle mass and a progressive increase of echogenicity, suggesting not only protein depletion but degenerative changes: during the ICU stay, the

This study describes the formulation optimization and body-cell distribution and clearance in mice of a dually fluorescent biodegradable poly avidin nanoassembly based on the novel Avidin-Nucleic-Acid-Nano-ASsembly (ANANAS) platform as a potential advancement of classic avidin/biotin-based targeted delivery. The nanoformulation circulates freely in the bloodstream; it is slowly captured by filter organs; it is efficiently cleared within 24-48 h, and it is poorly immunogenic. The system displays more favorable properties than its parent monomeric avidin and it is a promising tool for diagnostic purposes for future translational aims, for which free circulation in the bloodstream, safety, multifunctionality and high composition definition are all necessary requirements. In addition, the assembly shows a time-dependent cell penetration capability, suggesting it may also function as a NP-dependent drug delivery tool. The ease of preparation together with the possibility to fine-tune the surface composition makes it also an ideal candidate to understand if and how nanoparticle composition affects its localization.

We report the design of an integrated platform for on-chip electrical transduction of the surface plasmon resonance supported by a nanostructured metal grating. The latter is fabricated on the active area of a GaAs/AlGaAs photo-HEMT and simultaneously works as the electronic gate of the device. The gold plasmonic crystal has a V-groove profile and has been designed by numerical optical simulations. By showing that the numerical models accurately reproduce the phototransistors experimental response, we demonstrate that the proposed architecture is suitable for the development of a new class of compact and scalable SPR sensors.

A novel compact architecture implementi ng grating-coupled surface plasmon resonance (GCSPR ) based on polarization modulation in conical mounting is presented. In this system a plasmonic grating is azimuthally rotated in order to support the excitation of high-sensitivity surface plasmon polaritons (SPPs). At SPP resonance, a scan of the incident polarization is performed before and after the binding event and the phase term of the output trend is exploited as sensing parameter. The mechanical complexity of the SPR system is significantly reduced and a resolution down to 10 -7 refractive index units is assured. In this work a numerical study of the polarization-based grating-coupled SPR technique is performed and analyzed with Chandezon’s method. Therefore an experimental test on an assembled prototype is presented and applied to the detection of binding events on the grating surface (avidin/biotin reaction, DNA/PNA probes). Keywords: surface plasmon resonance, metallic gratings, conical mounting, polarization modulation, sensing, biotin/avidin, PNA, DNA

Grating Coupled-Surface Plasmon reflectivity measurements carried out under azimuth and polarization control (GC-SPR phi not equal 0 degrees)were used to optimize the process of gold surface dressing with poly(ethyleneoxide) (PEO) derivatives of different molecular weight, with the final goal to maximize the discrimination between specific and non-specific binding events occurring at the surface. The kinetics of surface deposition of thiol-ending PEOs (0.3, 2 and 5 kDa), introduced as antifouling layers, was monitored. Non-specific binding events upon immersion of the surfaces into buffers containing either 0.1% bovine serum albumin or 1% Goat Serum, were evaluated as a function of polymer size and density. A biorecognition event between avidin and biotin was then monitored in both buffers at selected low and high polymer surface densities and the contribution of analyte and fouling elements to the signal was precisely quantified. The 0.3 kDa PEO film was unable to protect the surface from non-specific interactions at anytested density. On the other hand, the 2 and 5 kDa polymers at their highest surface densities guaranteed full protection from non-specific interactions from both buffers. These densities were reached upon a long deposition time (24-30 h). The results pave the way toward the application of this platform for the detection of low concentration and small dimension analytes, for which both non-fouling and high instrumental sensitivity are fundamental requirements. (C) 2013 Elsevier B. V. All rights reserved.

An experimental prototype exploiting Grating-Coupled Surface Plasmon Resonance (GCSPR) based on polarization modulation has been assembled and tested for sensing purposes. The plasmonic gratings are azimuthally rotated in order to exploit the symmetry breaking for the excitation of highly sensitive Surface Plasmon Polaritons in conical mounting. By exploiting the optimal-polarization shift, a scan of the incident polarization is performed and reflectivity data are collected. The output signal exhibits a harmonic dependence on polarization and the phase term is considered as a parameter for sensing. Since the optical configuration is fixed during the analysis and the only degree of freedom is represented by the incident polarization, this setup provides a more compact and simplified architecture with respect to other. commercial SPR techniques, however assuring at the same time competitive performances in refractive index sensitivity and resolution. The employed metallic gratings are fabricated by interferential lithography and replicated onto resin substrates by soft-lithography techniques, thus thermally evaporated. (C) 2013 Elsevier B.V. All rights reserved.

In combination with standard transducers and data acquisition systems, computer vision can be adopted in order to perform the analysis of the behaviour of structures during dynamic tests such as earthquake simulations on shake tables. The paper describes the design and implementation of a machine vision system aimed at providing bi-dimensional position measurement of reflective markers directly placed on test specimens. The developed solution is composed of a scalable set of acquisition units, each consisting of a high definition digital camera and a personal computer. A sequence of images is acquired by the cameras and the position of the markers in the scene is estimated by means of a software application running on the computers. Each unit can perform measurements in a single plane which is defined in a previous calibration phase. The method has many advantages over the most commonly used acquisition devices such as accelerometers and potentiometers: first, the absence of contact between the acquisition device and the tested structure, which allows the non-invasive deployment of an arbitrary number of measurement targets, which is even more important in destructive tests, for preventing the loss of expensive transducers; second, the direct calculation of the position of an object in length units, without the need of post processing like integration and conversion, as required when using accelerometers in shake table tests. Besides, in the selected plane, thanks to the adoption of infrared illumination and filters to reduce environmental lighting interferences, each unit can follow the movements of a large number of markers (up to 50 for each camera in the performed tests) with a precision of around 0.05 mm. On the other hand, the method is by itself unable to overcome problems deriving from the three-dimensional movement of the selected markers. The paper also explains the different approaches and the corresponding results obtained while solving this issue.

We designed and experimentally realized the prototype for a bio-recognition device based on Grating Coupled Surface Plasmon Resonance (GCSPR) which can find a wide range of applications for detection of chemical and biological species. A sinusoidal grating (period of 500 nm and peak-to-valley height of 40 nm) was realized by Laser Interference Lithography (LIL) and replicated onto a polymeric resin film. After substrate coating with a Cr/Au film a thio-mPEO (Mw 5000) layer with a medium thickness of 4 nm was deposited onto the plasmonic surface. The SPR detection system allowed to detect the biological layer with a refractive index sensitivity of 995.2°/RIU. Our solution has been demonstrated to be a very sensitive platform for the development of a complete GCSPR biosensor.

Corrugated gratings coated with thin films of noble metals have been recognized to be useful substrates for bio-detection by means of the excitation of surface plasmon polaritons (SPP). These substrates show superior performances in terms both of detection limit and of simplicity of detection configuration compared to the classical Kretschmann SPP. A 1D sinusoidal corrugation of the metal-air interface has been fabricated by means of laser interference lithography and metal evaporation. In this paper we report progress in the optimization of the sinusoidal grating surface profile. The quality of the fabricated samples has been proved by the good agreement between experimental and simulated results. (C) 2011 Elsevier B.V. All rights reserved.

Every application of a Wireless Sensor Network (WSN) requires the data collected from sensor nodes to be reachable from the outside, in order to allow its processing and to obtain information from the monitored phenomena. Environmental protection and agriculture are examples of areas most likely to benefit from the deployment of WSNs. Devices equipped with temperature, humidity and light sensors could play a role in preserving the environment by providing early alerts and useful status information in real-time. Since such networks usually provide a huge amount of raw data, an easy way to organize, store and retrieve useful information is also needed. In this work we present REnvDB (RESTful Environmental DataBase), a novel database for Wireless Sensor Networks specifically designed for pervasive monitoring applications. The data model of the database is flexible enough to fulfill the requirements of most of the typical environmental monitoring systems. We also provided the database a RESTful interface, which can be used to expose the data collected by heterogeneous WSNs using the standard protocols of the World Wide Web. Thanks to its modular design and the use of metadata, the behavior of our RESTful interface can also be easily extended or modified according to the requirements and constraints of a specific context. Finally, the entire system has been implemented and tested in a real environment as part of a bigger project for the monitoring of an intensive agricultural field.

In this work, the characterization of a biodegradable bilayer system, used as controlled and combined drug delivery platform, is reported. For this aim, a bilayer system, composed of poly(lactic-co-glycolic acid) and poly(3-hydroxybutyric-co-3-hydroxyvaleric acid), was investigated under physicochemical and functional aspects by evaluating polymer/polymer and polymer/stent material interactions, the kinetic of in vitro degradation, and drug release properties, comparing results with the monolayer reference systems. Obtained results showed that the bilayer system allowed increasing the total amount of eluted Tacrolimus and Paclitaxel drugs with respect to the monolayer systems in the considered testing period and conditions. This evidence was associated to a faster degradation of the tested copolymers in the bilayered configuration, excluding a synergic effect of two drugs on delivery performance. In addition, a macromolecular relaxation process was identified to govern the PLX release from poly(lactic-co-glycolic acid), whereas a pure Fickian diffusion occurred in the delivery of Tacrolimus from poly(3-hydroxybutyric-co-3-hydroxyvaleric acid). © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010

Two different molecularly imprinted polymers (MIP1 and MIP2) in the form of submicron-particles were obtained by radical polymerization, using acetonitrile as a solvent, methacrylic acid (MAA) as a functional monomer, a cross-linking agent (trimethylolpropane trimethacrylate (TRIM) for MIP1 and pentaerythritol triacrylate (PETRA) for MIP2) and phenylalanine aminoacid (Phe) as a template molecule. The extraction of Phe template from polymer submicron-particles by washing steps allowed the formation of free recognition sites for the selective rebinding of template molecule. Rebinding ability was evaluated in acetonitrile and in phosphate buffered saline by chromatographic methods and compared to that of corresponding control polymers. As MIP1 showed a superior specificity towards Phe rebinding as compared to MIP2, it was selected as a component of a poly( l -lactic acid) (PLLA) based model sensor-scaffold. Impedance measurements, carried out on PLLA films loaded with as-produced, extracted or rebound MIP1 submicron-particles demonstrated the possibility to build a scaffold capable of sensing the amount of rebound template. In the future, devices incorporating MIP submicron-particles able to rebind extracellular matrix or transmembrane proteins will be respectively used as structures promoting cell adhesion and proliferation and sensor-films monitoring cell colonization.

Drug delivery systems based on synthetic polymers are widely employed in the treatment of several pathologies. In particular, the use of implantable devices able to release one or more active principles in a topic site with a controlled delivery kinetic represents an important improvement in this field. However, the release kinetic, that could be affected by different parameters, like polymer composition or chemical nature and initial drug loading, represents one of the problems related to the implantation of delivery systems. In this study, acrylic membranes with different macromolecular composition were prepared and studied analyzing delivery kinetic properties. Drug delivery systems were prepared using as matrix the copolymer poly(methylmethacrylate-co-butylmethacrylate) in three different compositions and folic acid (less hydrophobic) or Paclitaxel (more hydrophobic) as drugs, to evaluate the effect of macromolecular composition and hydrophilicity degree on the release properties. In addition, the effect of the initial drug loading was considered, loading drug delivery systems with four different initial drug percentages. Results showed a direct dependence of kinetics from macromolecular composition, hydrophilicity degree of solutes, and initial drug loading, allowing one to conclude that it is possible to design and to develop drug delivery systems starting from poly(methylmethacrylate-co-butylmethacrylate) matrices with specific properties by varying these three parameters.

The aim of the present work is the modification of a hydrophobic polymeric macromolecule, polymethylmethacrylate, by introducing hydrophilic moieties of 2-hydroxyethyl methacrylate within the polymer chain. Synthesis, characterization, and drug delivery control capabilities exerted on a highly hydrophobic drug (Paclitaxel) are illustrated. In particular, the dependency of the drug delivery kinetic on the fraction of hydrophilic units inserted in the copolymer chain was studied. Results showed that it is possible to have an increase of the kinetic delivery introducing hydrophilic units. In addition, a double control, diffusive and due to the relaxation of the molecules, on drug delivery was obtained.

The aim of the present work is the synthesis and characterization of polymer materials showing good adhesion, drug loading, and delivery properties, for potential cardiovascular application. In particular, poly(methylmethacrylate-co-acrylic acid) copolymers are prepared in different compositions by a radical polymerization and investigated as potential materials to coat metallic stents and to carry out a local drug release. Films obtained by dissolving the copolymer in an appropriate organic solvent (also loaded with an anti-restenosis drug, such as tacrolimus) are investigated: physicochemical properties, adhesiveness to metallic stent material, and kinetics of drug release in physiological environment are studied.

Davide Silvestri*, Maria Laura Coluccio**, Niccoletta Barbani, Gianluca Ciardelli, Caterina Cristallini, Carla Pegoraro, Paolo Giusti Department of Chemical Engineering, University of Pisa, via Diotisalvi 2, 56126 Pisa, Italy email: dav.silvestri@ing.unipi.it Department of Mechanics, Politecnico of Turin, c.so Duca degli Abruzzi 24, 10129 Turin, Italy Department of Chemical Engineering, CNR Institute for Composite and Biocompatible Materials, Pisa, Italy

The preparation of an enzymatic controlled drug release system from blends of PVA/starch/alphaA, in the form of films, is described. It was shown that alphaA hydrolyses the starch within these films, resulting in a time-dependent change of the porosity in the matrix. Films were characterized by calorimetric analysis to study the interactions between the enzyme and the polymeric constituents at the molecular level. The presence of alphaA, in fact, influenced the PVA crystallization in the blends. Release tests and permeability experiments were carried out to evaluate the transport properties of the films. An increase in porosity and permeability was observed by increasing alphaA content (16-28 wt.-%). Films loaded with theophylline and caffeine were also prepared to analyze drug release properties of the matrix. Drug release kinetics were coherent with the measured changes in porosity: at higher alphaA concentrations the amount of released drug increased under the influence of diffusion and erosion processes. The results obtained are promising for the realization of drug delivery devices for a rapid release or for the release of poorly soluble drugs which usually remain entrapped in the matrix.SEM images of a PVA/starch/alphaA film before (A) and after (B) the erosion.

The preparation of innovative polymeric systems using molecular imprinting technology for application in extracorporeal blood purification is described. Membranes based on a methylmethacrylate-co-acrylic acid copolymer, produced through the phase inversion method, were modified introducing into their structure specific binding sites for cholesterol molecule by adding molecularly imprinted nanoparticles in the membrane matrix. Membranes prepared are intended to selectively remove cholesterol from the blood by using interactions at a molecular level, between the membrane/nanoparticles devices and the template, created during the preparation of polymers. Three polymeric systems in form of nanoparticles were prepared differing in the polymerisation solvent (a mixture of acetonitrile and ethanol (1:1) or pure ethanol), and the molar ratio between the functional monomer and the cross-linker (2.3:1 and 1:1). Two out of three of the prepared polymers showed a very good template rebinding capacity both in phosphate buffer solution (pH 6.9) and in ethanol. In particular the nanoparticles rebound 115.4 mg cholesterol/g polymer in buffer solution, and 57 mg cholesterol/g polymer in ethanol. The deposition of the nanoparticles on the surface of the phase inversion membranes produced devices with interesting rebinding performances towards cholesterol in buffer solution: a specific recognition of 14.09 mg cholesterol/g system (membrane and nanoparticles) was detected, indicating maintained binding capacity of supported particles as well.

Bioartificial polymeric materials based on blends of dextran and poly(vinyl alcohol-co-acrylic acid) P(VA-co-AA) were prepared in the form of films and characterised to evaluate the miscibility of the natural component with the synthetic one. The idea of this work was to compatibilise PVA and dextran by introducing carboxylic groups along the PVA chains. The copolymer was synthesised and characterised in our laboratories. The results evidenced that the copolymer had an appropriate molecular weight and the content of PAA in the copolymer was 45% (weight). Then, films with different composition ratios were prepared by solution casting and analysed by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), chemical imaging analysis and mechanical tests. The results obtained indicated that the introduction of carboxylic groups along the PVA chains had a positive effect on the miscibility degree of the synthetic component with the biological one.