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Behavioural evidence, summarized in this narrative review, supports a developmental model of locomotor control based on increasing neural integration of spatial reference frames. Two consistent adult locomotor behaviours are head stabilization and head anticipation: the head is stabilized to gravity and leads walking direction. This cephalocaudal orienting organization aligns gaze and vestibula with a reference frame centred on the upcoming walking direction, allowing anticipatory control on body kinematics, but is not fully developed until adolescence. Walking trajectories and those of hand movements share many aspects, including power laws coupling velocity to curvature, and minimized spatial variability. In fact, the adult brain can code trajectory geometry in an allocentric reference frame, irrespective of the end effector, regulating body kinematics thereafter. Locomotor trajectory formation, like head anticipation, matures in early adolescence, indicating common neurocomputational substrates. These late-developing control mechanisms can be distinguished from biomechanical problems in children with cerebral palsy (CP). Children's performance on a novel navigation test, the Magic Carpet, indicates that typical navigation development consists of the increasing integration of egocentric and allocentric reference frames. In CP, right-brain impairment seems to reduce navigation performance due to a maladaptive left-brain sequential egocentric strategy. Spatial integration should be considered more in rehabilitation.

In this work the influence of poly(N-vinyl pyrrolidone) (PVP) concentration in water on the organization and dynamics of the corresponding macro-/nanogel networks has been systematically investigated. Irradiation has been performed at the same irradiation dose (within the sterilization dose range) and dose rate. In the selected irradiation conditions, the transition between macroscopic gelation and micro-/nanogels formation is observed just below the critical overlap concentration (∼1 wt%), whereas the net prevalence of intra-molecular over inter-molecular crosslinking occurs at a lower polymer concentration (below 0.25 wt%). Dynamic–mechanical spectroscopy has been applied as a classical methodology to estimate the network mesh size for macrogels in their swollen state, while 13C NMR spin–lattice relaxation spectroscopy has been applied on both the macrogel and nanogel freeze dried residues to withdraw interesting information of the network spatial organization in the passage of scale from macro to nano.

Radiation curing of an epoxy resin based blend is carried out in order to produce polymer matrices for high-performance composites. A suitable choice of both curing process and formulation parameters allows to irradiate at about 60°C. Moreover hydrothermal ageing is performed on cured materials and their properties have been evaluated

In this work Mode I fracture toughness behavior of Electron Beam cured unidirectional CFRP laminates is investigated by means of standardized Double Cantilever Beam (DCB) tests. A matrix system, comprising a DGEBA epoxy monomer and a typical initiator of cationic polymerization, was used and panel samples assembled by hand lay-up. Curing was achieved by 20 to 40 minutes irradiation on a pulsed 10 MeV Electron Beam accelerator. One batch of resin was also mixed with 10 phr of a PES thermoplastic monomer in order to enhance the matrix toughness. The influence of fibre-matrix adhesion, matrix toughening and matrix crosslinking density on the mode I delamination behavior have been investigated by correlating the results of DCB and Dynamic Mechanical Thermal Analysis (DMTA) tests.

Objectives: To develop a novel nomogram to identify candidates for active surveillance (AS) that combines clinical, biopsy and multiparametric magnetic resonance imaging (mpMRI) findings; and to compare its predictive accuracy to, respectively: (i) Prostate Cancer Research International: Active Surveillance (PRIAS) criteria, (ii) Johns Hopkins (JH) criteria, (iii) European Association of Urology (EAU) low-risk classification, and (iv) EAU low-risk or low-volume with International Society of Urological Pathology (ISUP) Grade Group (GG) 2 classification. Patients and Methods: We selected 1837 patients with ISUP GG1 or GG2 prostate cancer (PCa), treated with radical prostatectomy (RP) between 2012 and 2018. The outcome of interest was the presence of unfavourable disease (i.e., clinically significant PCa [csPCa]) at RP, defined as: ISUP GG (Formula presented.) 3 and/or pathological T stage (pT) ≥3a and/or pathological N stage (pN) 1. First, logistic regression models including PRIAS, JH, EAU low-risk, and EAU low-risk or low-volume ISUP GG2 binary classifications (not eligible vs eligible) were used. Second, a multivariable logistic regression model including age, prostate-specific antigen density (PSA-D), ISUP GG, and the percentage of positive cores (Model 1) was fitted. Third, Prostate Imaging-Reporting and Data System (PI-RADS) score (Model 2), extracapsular extension (ECE) score (Model 3) and PI-RADS + ECE score (Model 4) were added to Model 1. Only variables associated with higher csPCa rates in Model 4 were retained in the final simplified Model 5. The area under the receiver operating characteristic curve (AUC), calibration plots and decision curve analyses were used. Results: Of the 1837 patients, 775 (42.2%) had csPCa at RP. Overall, 837 (47.5%), 986 (53.7%), 348 (18.9%), and 209 (11.4%) patients were eligible for AS according to, respectively, the EAU low-risk, EAU low-risk or low-volume ISUP GG2, PRIAS, and JH criteria. The proportion of csPCa amongst the EAU low-risk, EAU low-risk or low-volume ISUP GG2, PRIAS and JH candidates was, respectively 28.5%, 29.3%, 25.6% and 17.2%. Model 4 and Model 5 (in which only PSA-D, ISUP GG, PI-RADS and ECE score were retained) had a greater AUC (0.84), compared to the four proposed AS criteria (all P&nbsp

Electrospun mats have been applied as toughening interlayers in high performance carbon fiber epoxy composites. While the toughening mechanism exerted by the mat at the interface is the subject of several recent studies, no investigations are reported on the aging behaviour of laminates comprising these nanostructured elements. This work investigates the influence of the combined effect of water and temperature (90 °C) on laminates with Nylon 6,6 electrospun membranes placed either at the middle plane only or at each interlayer. The water-uptake behaviour is modelled by a two-stage diffusion model and compared with the behaviour of the neat resin and of the laminate without mats. Interestingly, a lower water uptake is observed for the laminates with mat-modified interfaces and this is possibly due to a significantly reduced porosity. The effect of hydrothermal aging on the thermal (Tg) and mechanical properties (transverse flexural modulus and interlaminar shear strength) of the various laminates is also investigated.

To understand the multiparametric magnetic resonance imaging (mpMRI) interreader agreement between radiologists of peripheral and academic centers and the possibility to avoid prostate biopsies according to magnetic resonance imaging second opinion.This prospective observational study enrolled 266 patients submitted to mpMRI at nonacademic centers for cancer detection or at active surveillance begin. Images obtained were reviewed by 2 unblinded radiologists with 8 and 5 years' experience on mpMRI, respectively. We recorded Prostate Imaging Reporting and Data System (PI-RADS) v2 categories and management strategy changes after mpMRI rereadings. Interreader agreement was assessed by the Cohen kappa. For mpMRI second opinion, positive predictive value and negative predictive value were calculated.In the original readings, no lesions (ie, PI-RADS 2) were observed in 17 cases (6.5%). Reported index lesion (IL) PI-RADS category was 2 in 23 (8.5%), 3 in 85 (32%), 4 in 98 (37%), and 5 in 13 (5%) men, respectively. It is noteworthy that in 30 examinations (11%), an IL was recognized by radiologists, but a suspicious score was not assigned. According to first reading of mpMRI, initial clinical strategy included performing a targeted (226; 85%) or a systematic biopsy (8; 3%), scheduling the patient to an active surveillance program without repeat biopsy (10; 4%), or monitoring prostate-specific antigen without prostate sampling (22; 8%). The mpMRI rereads did not change IL PI-RADS category in 91 cases (38.5%), although in 20 (8.5%) and 125 (53%) IL PI-RADS was upgraded or downgraded, respectively (κ = 0.23). The clinical management changed in 113 patients (48%) (κ = 0.2). Overall, 102 targeted biopsies (51%) were avoided and 72 men (34.5%) were not submitted to biopsy after mpMRI second opinion. Positive predictive value and negative predictive value of the mpMRI rereading were 58% and 91%, respectively. Major limitations of the study are limited-time follow-up and the lack of a standard of reference for some men, who were not submitted to biopsy according to mpMRI second opinion.There is an important level of discordance between mpMRI reports. According to imaging second opinion, roughly half of targeted biopsies could be avoidable and 34.5% of men could skipped prostate sampling. Prospective randomized trials are needed to confirm our findings.

Responsive hydrogels filling the interstitial spaces of photonic crystals can form mesoscopically structured materials, which exhibit reversible shifts in the Bragg diffracted light as a response of environmental changes. These materials can be used to generate chemical or biochemical sensors. The present work reports on the synthesis and characterization of ethanol responsive hydrogels that can be used in the design of novel breathalyzers. The dynamic mechanical behavior of the macroscopic hydrogels and their swelling features in the presence of different liquids or vapors have been investigated to orientate the choice of the best responsive material and curing process. The swelling behavior of a selected hydrogel embedding the photonic crystal made of polystyrene nanoparticles as function of the concentration of ethanol vapor was studied through UV–Vis optical transmission spectroscopy and compared to the behavior of the macrogel analogue.

Poly(N-vinylpyrrolidone)-grafted-acrylic acid biocompatible nanogels (NGs) were prepared using an exiting industrial-type electron accelerator and setups, starting from semi-dilute aqueous solutions of a commercial PVP and the acrylic acid monomer. As a result, NGs with tunable size and structure can be obtained quantitatively. Sterility was also imparted at the integrated dose absorbed. The chemical structure of the NGs produced was confirmed through Fourier Transformer Infrared Spectroscopy (FT-IR). The molecular and physico-chemical properties of NGs, such as the hydrodynamic dimensions and surface charge densities, for various polymer and monomer concentrations in the irradiated solutions, are discussed here.

Objective The aim of the present study was to evaluate the impact of a multidisciplinary approach in patients' selection with advanced ovarian cancer (AOC) for different therapeutic strategies. Methods Patients referred at our institution between 2009 and 2012 for AOC were included. Primary multidisciplinary evaluation was performed in all patients. Different strategies included: 1. patients referred to primary neoadjuvant chemotherapy (NACT) and interval surgery (IDS) (group A); 2. patients considered for surgical exploration. After surgical exploration, patients were either considered for primary debulking (PDS; group B), or NACT (group C). Results A total of 363 patients were included. Of 38 patients (10.5%) in group A, 24 (63%) had sovradiaphragmatic/multiple liver metastases; 14 (37%) were excluded for PDS for anestehesiologic/medical reasons. Of 325 (89.5%) considered for surgical exploration, 295 (91%; group B) had primary surgery with debulking intent (N: 277) and were cytoreduced to no macroscopic disease (R0: N:200; 68%) o minimal RD

The work describes the preparation and physical-mechanical characterization of unidirectional CFRP panels manufactured by an electron beam curing technique. Delamination fracture toughness in Mode I and II is investigated in order to evaluate the influence of fiber–matrix adhesion strength, matrix toughness and matrix crosslinking density as determined by the radiation curing process. A matrix system comprising a DGEBA epoxy monomer and an initiator of cationic polymerization have been used, with one batch of resin mixed with a PES monomer in order to enhance matrix toughness. Curing was achieved with a pulsed 10 MeV Electron Beam accelerator. Thermally cured composite systems have also been manufactured and tested for comparison. Results from double cantilever beam and end notched flexure delamination tests have been analyzed and correlated with results from short beam shear, dynamic mechanical thermal analysis tests and SEM micrographs of delaminated surfaces. POLYM. COMPOS., 35:1529–1542, 2014. © 2013 Society of Plastics Engineers

In this paper the network structure of e-beam cured DGEBF based epoxy resins is investigated. Two epoxy systems, having different reactivity and cured in different process conditions, were analyzed through solid state NMR spectroscopy. The analysis shows that the more reactive system has higher cross-linking density and higher uniformity of network distribution. Similar information were obtained, in a previous work, on the same systems through dynamic mechanical thermal analysis. It is worth noting that unlike DMTA tests, which interfere with the molecular structure of the analyzed material, due to the heating during the analysis itself, more reliable information, without any artefact, are obtained by solid state NMR, carried out at constant room temperature.

In this paper two systems, polyethylene (LDPE) and polyethylene/commercial organo-modified montmorillonite (LDPE/OMMT) nanocomposite, were subjected to e-beam irradiation at different doses and both the molecular modifications and mechanical properties have been investigated through solubility, FT-IR, calorimetric and tensile tests. Moreover, in some of the irradiated systems photo-oxidation aging was performed and its effects were studied. The results show an enhancement with irradiation of the positive effect of the nano-filler loading, related to the increase of the mechanical properties, due to the increase of the nano-filler polymer interaction. Nevertheless calorimetric and FT-IR data indicate that the well known reduction of LDPE/OMMT nanocomposite resistance to photo-oxidation ageing, with respect to LDPE, is amplified by ionizing radiation.

A model epoxy resin/anhydride system, modified with a polyethersulfone (PES) engineering thermoplastic toughening agent, has been studied under hydrothermal ageing in order to investigate the modification of the thermal, morphological and mechanical behaviour through dynamical mechanical thermal analysis, SEM microscopy and fracture toughness test respectively. Two different concentrations of the toughening agent were used in the blends and two ageing conditions have been considered, consisting of the immersion of the samples in distilled water at constant temperature of 70 °C for 1 week and for 1 month. Dynamical mechanical thermal analysis results on hydrothermally aged materials indicated the occurrence of progressive segregation effects with the formation of regions with different cross-linking degrees. Fracture toughness tests showed an increase of the K IC value with the increase of the toughening agent concentration, revealing both a dramatic decrease of the same parameter after 1 week ageing for all the materials and the tendency to reach an almost constant value after 1 month ageing for all the formulations, with a slight increase with respect to 1 week ageing. These results have been interpreted on the basis of the SEM analysis, showing the presence of a well defined micrometric PES particles distribution in the epoxy/anhydride matrix, and discussed in the light of different water absorption mechanisms at short and long ageing times.

The hydrothermal ageing of epoxy–thermoplastic blends, used as matrices for carbon fibre composites, cured by electron beam, has been studied. Two different thermoplastic percentages have been adopted. A suitable choice of both curing process and formulation parameters allows to carry out irradiation at mild temperature with several advantages, coming from a “non thermal” process, for both the final properties of the materials and the environment. Nevertheless the occurring of vitrification phenomena needs the use of a short thermal treatment after irradiation on the already solid materials, in order to complete the cure reactions. Radiation cured epoxy based matrices have been subjected to a thermal and moisture absorption ageing treatment and its influence on the thermal and mechanical properties has been investigated through dynamic mechanical thermal analysis and fracture toughness tests. The results have been interpreted on the basis of the different curing degree reached by the investigated systems and in the light of their morphological structures. Plasticization, thermal curing and degradation reactions occur in different extent depending on the kind of the material. In particular, for fracture properties, a better resistance to ageing is shown by the system at higher thermoplastic concentration.

Polymerization of an acrylate derivative of bisphenol-A by ionizing radiation in the presence of an organically modified montmorillonite was carried out in order to produce a flame-retardant composite. The measurement of the thermal effect during irradiation indicates that radiation curing of pure resin and resin-clay mixtures occurred in both cases. Moreover, differential scanning calorimetry and dynamic mechanical thermal analysis showed that a curing completion can be obtained by thermal curing after irradiation with a significant increase of the glass transition temperature. The morphology was investigated by X-ray diffraction and transmission electron microscopy. These have indicated that gamma irradiation leads to the formation of a microcomposite structure after radiation curing. The flame resistant characteristics were studied by means of thermal gravimetric analysis under nitrogen and air and by cone calorimeter tests. In particular, thermal gravimetric analysis in air showed that the presence of the dispersed clay in the polymer matrix increases the oxidation temperature. This is attributed to the formation of a more stable char, due to a protective skin of clay aggregates that builds up on the surface of the volatilizing polymer matrix during thermal degradation which protects the charred polymer from reactions with oxygen. Finally, the cone calorimeter tests show a reduction of heat release of the clay-polymer composite with respect to the neat resin. The contribution of the clay in reducing the rate of heat release is attributed to the dispersion of the filler that allows build-up of an inorganic surface layer at a rate which is sufficient for effectively compete with the feeding of the flame with combustible pyrolysis products. © 2006 Wiley Periodicals, Inc. Adv Polym Techn 25: 109–120, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20063

In this work two epoxy resin model systems, whose monomers are typically used in structural composites, were thermally cured in different cure conditions in order to obtain different cross-linking densities. Their molecular structures were investigated through solid state NMR spectroscopy in order to correlate them to the cure process conditions used and the results were discussed in the light of the dynamical mechanical thermal analysis (DMTA) performed.

Nanogels (NGs), or small particles formed by physically or chemically crosslinked polymer networks, represent a niche in the development of “smart” nanoparticles for drug delivery and diagnostics. Yet, they offerunique advantages over other systems, including a large and flexible surface for multivalent bio-conjugation; an internal 3D aqueous environment for incorporation and protection of (bio)molecular drugs; the possibility to entrap light-activemolecules, metal or mineral nanoparticles for imaging or phototherapeutic purposes; stimuli-responsiveness to achieve temporal and/or site control of the release function and biocompatibility. The availability of inexpensive, robust and versatile synthetic methodologies is at the basis of the development of effective nanogel-based theragnostic devices. In particular, we have established that nanogels can be produced with high yields and through-puts by pulsede-beam irradiation of dilute aqueous solutions of water-soluble biocompatible polymers e.g. poly(N-vinyl pyrrolidone), and functional acrylic monomers, such as acrylic acid or (3-aminopropyl) methacrylamide hydrochloride, using industrial electron accelerators and set-ups (see Figure 1). [1-4] Nanogels are the result of chemical follow-up reactions initiated by a continuous series of electron pulse-generated hydroxyl radicals in de-aerated water. A number of radical sites are generated on the polymer chains,which may have a different fate depending onthe system composition and irradiation conditions.Intra-molecular and inter-molecular radical recombination as well as disproportionation, chain scission and monomer or short polymer segments grafting may occur up to different extent. As a result, crosslinked-core nanoparticles with multi-armed surfaces can be generated, with controlled size, crosslinking density, surface electric charge density, number and nature of functional groups.No recourse to organic solvents, toxic initiators or catalysts and surfactants is made, therefore expensive or time-consuming purification procedures are not required. Simultaneous sterilization can be achieved depending on the irradiation doses. Long-term colloidal stability in the formof aqueous dispersions and redispersability from the freeze-dried form are advantageous properties especially in the view of a pharmaceutical use. Nanogels have been decorated with fluorescent probes, peptides, antibodies or oligonucleotides and/or conjugated to both molecular and macromolecular model drugs to demonstrate their amenability to be transformed into bio-hybrid, smart drug nanocarriers. All the base nanogels have been proved to benot cytotoxic or genotoxic at the cellular level. Indeed, they showed a good affinity for cells, as they rapidly and quantitatively bypass the cellularcompartments, to accumulate in specific cell portions for the first hours, to bethen completely released from the cells after 24 h.[5] In particular, active targeting features toward specific cell types and smart delivery functions of model chemotherapeutics of purposely designed bio-hybrid nanogels will be presented.