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The impact of prefermentative addition of five single-enzyme activities (pectin lyase, polygalacturonase, pectin methyl esterase, xylanase, and arabinase) on the phenolic content, colour characteristics, and volatile composition of grape musts resulting from pellicular maceration of Chardonnay, Arneis, Greco, and Falanghina white varieties was studied with the aim of enhancing aroma composition without negatively affecting colour perception. In addition, standard physicochemical parameters were determined. Pectin lyase, polygalacturonase, and arabinase enzymes reduced the must browning, when compared with untreated control, as reported by lower total polyphenol index, absorbance at 420 nm, and a* colour coordinate for all varieties tested. Regarding the volatile composition determined by solid-phase extraction and GC-MS analysis, variety effect was observed for the enzyme treatments studied. The concentration of free vanillin decreased significantly in these last three varieties using polygalacturonase and arabinase treatments whereas 4-vinylguaiacol increased in pectin lyase-treated samples. Free terpene compounds, such as furan linalool oxide, increased in Chardonnay and Falanghina varieties using polygalacturonase, xylanase, and arabinase for the second variety whereas pectin lyase for the first one. Contrarily, glycosylated terpenes, such us (Z)-8-hydroxylinalool, decreased when using pectin lyase and xylanase for Arneis; however, it also occurred for Falanghina using polygalacturonase treatment. The xylanase activity influenced mostly the volatile composition of the Arneis variety whereas arabinase did for Greco and Falanghina. The differences between enzyme-treated grape musts and control samples were less evident on the Chardonnay variety. Therefore, enzyme activity can affect the volatile composition of grape must differently depending on the target variety. [Display omitted] • Single-activity enzymes tested for pellicular maceration of four white varieties. • Pectinlyase, polygalacturonase and arabinase increased must yield-reducing browning. • All varieties had similar patterns for free volatiles using some enzyme treatments. • The variety effect prevails over enzyme activity mostly for glycosylated volatiles. • Xylanase affected mostly Arneis volatiles while arabinase for Greco and Falanghina. [ABSTRACT FROM AUTHOR]

Biomedical grade UHMWPE double lap joint, welded by a diode laser, has been mechanically characterized by static and dynamic tests. A nanocomposite sheet (UHMWPE filled with low carbon nanoparticles amount) was interposed between two polymeric sheets in order to absorb the laser light, sealing the sheets by means of a melting process. Fatigue test has been performed in the joint with 0.016 wt% of carbon nanofiller for its best mechanical static resistance among those studied. Its fatigue limits resulted to be equal to 22000 cycles. Breaks occurred at the 2nd welded interface, where a poor melting process weakens the entire joint. [ABSTRACT FROM AUTHOR]

Background To analyze the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional approach (IMA) on ventilator-associated pneumonia (VAP) rates in 11 hospitals within 5 cities of Argentina from January 2014-April 2017. Methods A multicenter, prospective, before–after surveillance study was conducted through the use of International Nosocomial Infection Control Consortium Surveillance Online System. During baseline, we performed outcome surveillance of VAP applying the definitions of the Centers for Disease Control andPrevention's National Healthcare Safety Network. During intervention, we implemented the IMA, which included a bundle of infection prevention practice interventions, education, outcome surveillance, process surveillance, feedback on VAP rates and consequences, and performance feedback of process surveillance. Bivariate and multivariate regression analyses were performed using a logistic regression model to estimate the effect of the intervention. Results We recorded 3,940 patients admitted to 14 intensive care units. At baseline, there were 19.9 VAPs per 1,000 mechanical ventilator (MV)-days—with 2,920 MV-days and 58 VAPs, which was reduced during intervention to 9.4 VAPs per 1,000 MV-days—with 9,261 MV-days and 103 VAPs. This accounted for a 52% rate reduction (incidence density rate, 0.48; 95% confidence interval, 0.3-0.7; P .001). Conclusions Implementing the IMA was associated with significant reductions in VAP rates in intensive care units within Argentina. [ABSTRACT FROM AUTHOR]

Different tissues are used for stable isotope analysis in cetacean investigations. However, variation in the isotopic composition of tissues with different turnover rates has been reported for cetaceans. To better understand stable carbon and nitrogen isotopes (δ13C and δ15N) in skin compared to other tissues, this study assessed the isotopic variation among the liver, muscle, and skin of Guiana dolphins (Sotalia guianensis), as well as the influence of sex on these variations. No differences were found in δ13C among male tissues, but females showed lower values in the liver compared to muscle and skin. Differences in δ15N were observed among all tissues, with different variation patterns for males and females. Four females were distinguished from males and other females by their 13C depletion in all tissues and δ15N variation pattern. We conclude that skin and muscle may be equivalent in δ13C values for Guiana dolphins. The multiple-tissue analysis brings new insights into their feeding ecology and provides background for stable isotope analysis using non-destructive sampling techniques in small cetaceans. • Skin and muscle showed similar δ13C and δ15N values. • Males and females had different δ15N variation patterns among tissues. • Lower δ13C values were observed in female livers. • 13C depletion in all tissues of four females indicated different feeding strategy. • A different δ15N variation pattern among tissues was found in 13C-depleted females. [ABSTRACT FROM AUTHOR]

Ultrasonic Synthetic Aperture Focus (SAF) techniques are commonly used to image structural defects. In this paper, a variation of SAF based on ideas borrowed from Matched Field Processing (MFP) is evaluated to reduce artifacts and sidelobes of the resulting images. In particular, instead of considering the full RF ultrasonic waveforms for the SAF time backpropagation, only selected features from the waveforms are utilized to form a “data vector” and a “replica” (expected) vector of MFP. These vectors are adaptive for the pair of transmitter-receiver and the focus point. The image is created as a matched filter between these two vectors. Experimental results are shown for an isotropic and homogenous metallic plate with simulated defects, probed by six piezoelectric patches used as receivers or transmitters. [ABSTRACT FROM AUTHOR]

Light is perceived and transduced by fungi, where it modulates processes as diverse as growth and morphogenesis, sexual development and secondary metabolism. A special case in point is that of fungi with a subterranean, light-shielded habitat such as Tuber spp. Using as reference the genome sequence of the black truffle Tuber melanosporum , we used bioinformatic prediction tools and expression data to gain insight on the photoreceptor systems of this hypogeous ectomycorrhizal fungus. These include a chromophore-less opsin, a putative red-light-sensing phytochrome not expressed at detectable levels in any of the examined lifecycle stages, and a nearly canonical two-component (WC-1/WC-2) photoreceptor system similar to the Neurospora white collar complex (WCC). Multiple evidence, including expression at relatively high levels in all lifecycle stages except for fruiting-bodies and the results of heterologous functional complementation experiments conducted in Neurospora , suggests that the Tuber WCC is likely functional and capable of responding to blue-light. The other putative T. melanosporum photoreceptor components, especially the chromophore-less opsin and the likely non-functional phytochrome, may instead represent signatures of adaptation to a hypogeous (light-shielded) lifestyle. [ABSTRACT FROM AUTHOR]

Abstract: Vibrothermography is a sensitive, very fast, and full-field NDE imaging technique that uses ultrasound-generated heat as defect detection mechanism. Recent studies have shown that localized heating in cracked metallic beams is primarily generated by frictional rubbing on crack faces and local plastic deformations past the crack tip. As defects without contact surfaces (like air porosity in castings or delaminations in composites) are considered, these mechanisms are no longer effective in explaining heat generation. Hence, vibration damping and viscoelastic effects are expected to play a key role in this case. This study aimed to investigate the fundamental physics governing the damping-related viscoelastic heat generation and thermal diffusion processes in vibrothermography. The relationship among vibrational mode shape, ultrasound excitation frequency and energy dissipation in defective areas has been probed by means of concurrent measurements of the vibration and heating responses at specific flexural resonances. Experimental tests were carried out on a AISI 304 steel beam in which an array of synthetic defects, consisting of 27 flat-bottom holes filled with a viscous material, had been manufactured. A clear correlation was found between the heating rate and the vibration mode shape when the beam is vibrating at one of its resonant frequency. Moreover, by defining the vibration-induced heating ratio (VHR) as the ratio between the temperature rise slope and the vibration velocity amplitude, it was observed that this ratio is independent from the resonant frequency. [Copyright &y& Elsevier]

Abstract: In this paper some preliminary results about the sensing properties of a single-mode silica fiber Bragg grating (FBG) coated with a poly(methyl methacrylate) (PMMA) thin layer are reported. The PMMA coating on the fiber grating was deposited by using a micro-pipette bulb as mechanical vessel filled with polymer solutions in acetone. For ethanol sensing tests, the FBG sensor was placed in a measurement chamber equipped with a controlled gas system, then the output response was acquired using an optical spectrum analyzer which also provided laser illumination. Absorption of ethanol from the gas phase onto the PMMA layer causes swelling which can be recorded as an extension/compression of the fiber grating. As a consequence of this transduction effect, the peak shift response can be related to the ethanol concentration. Based on this simple principle, detection of low alcohol concentrations can be easily obtained. [Copyright &y& Elsevier]

Abstract: A combined method for the simultaneous measurement of the clamping pressure distribution and endplates deformation in polymer electrolyte fuel cells (PEFC) is presented. The proposed approach, which allows overcoming some important limitations associated with the use of conventional pre-scaled pressure films, is used to investigate the correlation between the actual pressure distribution on the membrane electrode assembly (MEA), the endplate out-of-plane deformation and the applied clamping torque, for two single fuel cells assembled with either copper or aluminium/copper endplates. Results proved that, in point-load design PEFCs, both pressure magnitude and distribution are affected by endplates deformation and thickness mismatching between the sealing gasket and the MEA. Moreover, while the average pressure on the MEA displays a slight increase (+25%) as the clamping torque is raised from 5 to 10Nm, it increases monotonically on the sealing gasket, with local peaks that exceed the saturation level of the sensor array (20.7MPa). A dimensionless uniformity index has been introduced to assess the uniformity of the pressure distribution, allowing an easy comparison of different fuel cell assembly configurations. The proposed methodology might assist the design of next-generation fuel cells or could be used as a powerful validation tool for detailed finite element models. It can also be applied to study other kind of fuel cells and batteries as well. [Copyright &y& Elsevier]

Abstract: The present study addresses the question of evaluating, by combining both experimental and numerical methods, the stress/strain distribution within a standardized composite femur implanted with an anterograde intramedullary nail. A transverse diaphyseal fracture has been introduced in order to evaluate the implant response in the early postoperative clinical stage. By comparing these experimental data with those obtained in the fully healed stage, in which the bone continuity had been recovered, it was possible to get information on load sharing between the bone and the intramedullary nail, location of high strain concentrations, bone relative motion at the fracture site, and stiffness reduction caused by bone discontinuity. Experimental data were correlated with those predicted by a validated 3D finite element model of the complete implant/femur assembly to investigate the full field stress distribution either in the cortical bone, in the nail or in the locking screws. The obtained results suggest that full weight bearing in the immediate post-operating stage should not be allowed since high stress levels are generated in the outer shell of the cortical bone either around the proximal screw hole or the upper locking screw hole. Long-term implant reliability should be guaranteed instead, since after fracture consolidation equivalent von Mises stresses never exceed critical levels neither in the bone nor in the implant. [Copyright &y& Elsevier]

Background: To evaluate the activity and safety of nonpegylated liposomal doxorubicin (Myocet™) when substituted for doxorubicin in the R-CHOP regimen (R-COMP). [ABSTRACT FROM PUBLISHER]

Abstract: Static and dynamic three-point bending tests were carried out in order to investigate the structural response (collapse modes, energy dissipation, strain rate sensitivity) of two different typologies of aluminium foam sandwich (AFS) panels, consisting of a closed-cell aluminium foam core with either two integral (Schunk) or two glued (Alulight) faces. Impact measurements were performed by a bi-pendulum testing machine designed by the authors. It was found that different collapse modes can be obtained for samples with identical nominal dimensions, depending on the support span distance and on the own AFS properties. Simplified theoretical collapse models were introduced to explain the observed experimental behaviour, showing good agreement between predicted and experimental limit loads. As far as energy dissipation is concerned, no strain rate sensitivity was found for initial impact velocity up to about 1.2m/s. [Copyright &y& Elsevier]

Abstract: This study aims to evaluate experimentally the behaviour after fracture consolidation of two intramedullary Gamma nail implants, having one (G1) or two (G2) distal screws, respectively. Nails have been implanted into standardized synthetic femora, instrumented with strain gauges. Strains measurements, supported by finite element numerical modelling, showed that the G2 implant, although ensuring higher flexional and torsional stiffness, can lead to localized contacts that occur between the tip of the nail and the femoral endosteum. This might be one of the reasons of the complications associated with pain in the mid-portion of the thigh after implantation which has been reported in several clinical studies when Gamma nails with two distal screws are used. [Copyright &y& Elsevier]

Abstract: In this paper the structural performance of aluminium alloy foams have been investigated under both static and dynamic compression loads. Three foam typologies (M-PORE, CYMAT, SCHUNK) in a wide range of density (from 0.14 to 0.75g/cm3), made by means of different process-routes (melt gas injection, powder metallurgy, investment casting) have been analysed. Foams microstructural characterization has been carried out through morphometric measurements by means of Scanning Electron Microscopy (SEM) and Computed Tomography (CT) and subsequent digital image processing in order to determine average cells size and cell distributions on different section planes. The experimental study aims to assess the strain rate sensitivity and energy absorption capability of commercially available metal foams and to point out the correlation between the mechanical behaviour and the physical and geometrical properties of the foam. It has been found that the specific energy dissipation of foams with similar density can be quite different: for the same volume of foam, average values of 1770, 1780 and 5590J/kg at 50% nominal compression have been measured on M-PORE (0.19g/cm3), CYMAT (0.28g/cm3) and SCHUNK (0.28g/cm3) foams, respectively. Impact tests showed that the dependence of the plateau stress on strain rate could be considered negligible for M-PORE and CYMAT foams while it is quite remarkable for SCHUNK foams. Moreover, it was found that the peak stress of CYMAT foams has a quite large sensitivity on the loading rate. [Copyright &y& Elsevier]

[Display omitted] • Isotopic niche partitioning was first assessed in a tropical cetacean community. • Rough-toothed dolphin has the most segregated and wide isotopic niche area. • Species presenting site fidelity have a high probability (>60%) of niche overlap. • Atlantic spotted and Guiana dolphins showed a wide δ15N and δ13C range, respectively. • The narrowest and most overlapped franciscanas' isotopic niche was first reported. Species in sympatry can coexist due to some degree of niche partitioning. Four cetacean species, Guiana (Sotalia guianensis), franciscana (Pontoporia blainvillei), Atlantic spotted (Stenella frontalis), and rough-toothed dolphins (Steno bredanensis), frequently occur in Ilha Grande Bay (RJ), with three of them presenting residence pattern. This tropical bay is considered a biodiversity hotspot and preserved by marine protected areas, though located in a highly developed region of the Southwestern Atlantic Ocean. To verify niche partitioning and segregation in these species and to explore the trophic structure of this cetacean community, their isotopic niches were investigated through carbon (δ13C) and nitrogen (δ15N) stable isotopes in the muscle of specimens stranded in the region between 2012 and 2022. The rough-toothed dolphin had the largest niche area and high segregation. On the other hand, there was a high niche overlap between the species that have site fidelity patterns in the bay. The Atlantic spotted dolphin had the highest values for almost all the Layman metrics, a large niche area, and trophic diversity; the Guiana dolphin explored a diverse variety of resources, and the franciscana dolphin presented the narrowest and most overlapped niche and the lowest niche diversification. This is the first study to access the trophic ecology of this cetacean community. Our results indicate that the region is an important foraging area for three of the studied species, with a high diversity and availability of resources that might enable the high niche overlap observed for resident species. The findings for the threatened and small franciscana population in this recently discovered habitat bring concern. Therefore, the area deserves conservation attention to prevent anthropogenic stressors from interfering in the relationship balance between these sympatric predators. [ABSTRACT FROM AUTHOR]