210 research outputs found

    Valutazione delle lesioni nell\u2019impatto ciclista adolescente -veicolo con simulazione multibody

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    Le situazioni di impatto e la dinamica di ciclista e pedone sono le informazioni fondamentali per lo sviluppo di soluzioni efficaci per migliorare la protezione del pedone e del ciclista in caso di urto con autovetture. La casistica degli incidenti a Palermo, negli ultimi anni, avvenuti su strade urbane (84%) che coinvolgono adolescenti (6,4%), mostra che i ciclisti hanno in genere una posizione di impatto superiore rispetto al pedone, con una quota maggiore di lesioni per urti nella zona del parabrezza. In questo lavoro \ue8 eseguita la simulazione dinamica per lo studio delle lesioni alla testa e al torace dell\u2019adolescente, tra una bicicletta generica e un modello di auto che presenta caratteristiche vantaggiose per la sicurezza del pedone o del ciclista. Il software SimWise (Visual Nastran) \ue8 stato usato per la simulazione multibody dell\u2019impatto; il modello antropomorfo, l'auto e le biciclette sono quelli utilizzati in lavori precedenti. L'attenzione \ue8 su un ciclista adolescente, perch\ue9 i relativi dati di lesione si trovano in letteratura con difficolt\ue0. I dodici test d\u2019impatto completo (auto contro ciclista) hanno come parametri principali: velocit\ue0 del veicolo (20, 30, 40 e 50 km/h), con tre diverse posizioni del ciclista rispetto al veicolo: frontale, laterale e posteriore. La posizione di impatto della testa (sopra il cofano, nel parabrezza), determinato dalla prova di crash, mostra che la protezione del ciclista dovrebbe essere migliorata nella zona pi\uf9 alta del parabrezza, rispetto a quelle pedonali. La ferita alla testa viene analizzata utilizzando il parametro HIC e la ferita al torace \ue8 analizzata secondo il criterio dei 3 ms; viene calcolata la probabilit\ue0 AIS 4 +, concludendo che la lesione alla testa \ue8 pi\uf9 pericolosa in caso di pedone adolescente, mentre la ferita della cassa toracica \ue8 pi\uf9 pericolosa nel caso di ciclista adolescente. Inoltre il ciclista adolescente ha una maggiore possibilit\ue0 di sopravvivenza rispetto al ciclista adulto. Incidentologia e simulazioni mostrano che il parabrezza \ue8 una posizione di impatto frequente per testa e torace

    Over and beyond the Primate baubellum Surface: A “Jewel Bone” Shielded in Museums

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    Computed Tomography (CT), mostly used in the medical field, has also recently been involved in Cultural Heritage studies, thanks to its efficiency and total non-invasiveness. Due to the large variety of sizes and compositions typical of Cultural Heritage objects, different X-ray sources, detectors, and setups are necessary to meet the different needs of various case studies. Here, we focus on the use of micro-CT to explore the morphology and shape of a small, neglected bone found inside the clitoris of non-human primates (the baubellum), which we obtained by accessing two prestigious primatological collections of the American Museum of Natural History (New York, NY, USA) and the National Museum of Natural History (Washington, DC, USA). Overcoming methodological limits imposed by the absence of homologous landmarks, we combined the use of the non-invasive 3D micro-CT and a recently released landmark-free shape analysis (the alpha-shape technique) to objectively describe and quantify the shape complexity of scanned primate baubella. Micro-CT provided high-resolution results, overcoming constraints linked to museum policy about non-disruptive sampling and preserving samples for future research. Finally, it proved appropriate as post-mortem sampling had no impact on protected wild primate populations

    The Transverse Crack Tension test revisited: An experimental and numerical study

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    Several problems arise when measuring the mode II interlaminar fracture toughness using a Transverse Crack Tension specimen; in particular, the fracture toughness depends on the geometry of the specimen and cannot be considered a material parameter. A preliminary experimental campaign was conducted on TCTs of different sizes but no fracture toughness was measured because the TCTs failed in an unacceptable way, invalidating the tests. A comprehensive numerical and experimental investigation is conducted to identify the main causes of this behaviour and a modification of the geometry of the specimen is proposed. It is believed that the obtained results represent a significant contribution in the understanding of the TCT test as a mode II characterization procedure and, at the same time, provide new guidelines to characterize the mode II crack propagation under tensile loads

    Interception of vertically approaching objects: temporal recruitment of the internal model of gravity and contribution of optical information

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    introduction: recent views posit that precise control of the interceptive timing can be achieved by combining on-line processing of visual information with predictions based on prior experience. Indeed, for interception of free-falling objects under gravity's effects, experimental evidence shows that time-to-contact predictions can be derived from an internal gravity representation in the vestibular cortex. however, whether the internal gravity model is fully engaged at the target motion outset or reinforced by visual motion processing at later stages of motion is not yet clear. moreover, there is no conclusive evidence about the relative contribution of internalized gravity and optical information in determining the time-to-contact estimates.methods: we sought to gain insight on this issue by asking 32 participants to intercept free falling objects approaching directly from above in virtual reality. object motion had durations comprised between 800 and 1100 ms and it could be either congruent with gravity (1 g accelerated motion) or not (constant velocity or -1 g decelerated motion). we analyzed accuracy and precision of the interceptive responses, and fitted them to bayesian regression models, which included predictors related to the recruitment of a priori gravity information at different times during the target motion, as well as based on available optical information.results: consistent with the use of internalized gravity information, interception accuracy and precision were significantly higher with 1 g motion. moreover, bayesian regression indicated that interceptive responses were predicted very closely by assuming engagement of the gravity prior 450 ms after the motion onset, and that adding a predictor related to on-line processing of optical information improved only slightly the model predictive power. discussion: thus, engagement of a priori gravity information depended critically on the processing of the first 450 ms of visual motion information, exerting a predominant influence on the interceptive timing, compared to continuously available optical information. finally, these results may support a parallel processing scheme for the control of interceptive timing

    The activity of intravesical hyaluronic acid and chondroitin sulfate administration on urothelial gene expression. Preliminary results on the epidermal growth factor receptor and fibronectin gene expression evaluated in bladder washings of patients affected by non muscle-invasive bladder cancer

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    Introduction & Objectives Hyaluronic acid (HA) and chondroitin sulfate (CS) are two major constituents of the bladder glycosaminoglycan layer. Recent data show that Fibronectin (FN) and Epidermal Growth Factor Receptor (EGFR) gene expression can be measured in bladder washings and could represent potential biomarkers of urothelial damage and tumor aggressiveness, respectively (1,2). The aim of our study was to investigate the interference of a single intravesical instillation of HA-CS solution on the expression of FN and EGFR genes in patients affected by non-muscle-invasive bladder cancer (NMIBC). Material & Methods A prospective double-blinded study included patients undergoing adjuvant intravesical therapy for NMIBC and age matched healthy controls. For EGFR evaluation, a single HA-CS solution was administered intravesically 14 days after transurethral resection of high risk NMIBC, before the start of the adjuvant therapy. For FN evaluation, a single HA-CS instillation was administered to patients showing local toxicity secondary to intravesical adjuvant therapy. Samples of bladder washings were collected before and one week after the HA-CS instillation, obtaining a cellular pellet stored at -80 °C. Cellular RNA was isolated by a miRNeasy Mini Kit (Qiagen¼) and cDNA, obtained using a “High Capacity cDNA Reverse Transcription Kit” (Life Technologies¼) was used to perform a gene expression analysis by a Real Time PCR. EGFR and FN gene expression values were expressed in FOLDs of change compared to healthy controls (FN and EGFR=1). Results Thirty-eight patients and 5 controls entered the study. Seventeen and 21 patients were evaluated for FN and EGFR respectively. In 21 patients with high risk NMIBC, the median EGFR expression decreased from 2.4 folds (range: 0.1-39.0) to 1.0 fold (range: 0.05-36.8) showing a statistically significant decrease of 58.3% (p<0.02). In patients showing clinically relevant toxicity secondary to intravesical adjuvant therapy (BCG in 9 and Epirubicin in 8 patients) the median FN expression value dropped from 1.8 folds (range: 0.07-8.1) to 0.9 fold (range: 0.1-7.5) after HA-CS administration with a statistically significant decrease of 50% (p<0.05). Conclusions FN gene expression in bladder washings appears related to the intensity of the urothelial damage, reaching higher expression levels in case of severe toxicity induced by intravesical adjuvant therapy (2). In our experience the FN gene expression significantly decreases a week after the administration of HA-CS solution with contemporary symptomatic relief. Moreover the urothelial EGFR gene expression resulted significantly lowered one week after the HA-CS intravesical administration. The reduced availability of its receptor could limit the proliferative activity of EGF on the urothelium promoting recurrence and progression. Acknowledgements: GSTU Foundation References: 1. Serretta V, et al. Feasibility of EGFR evaluation in bladder washings of patients affected by non muscle-invasive bladder cancer. J Urol, 2016. 195 (4S): e327. 2. Alonge V, et al. Correlation between Fibronectin gene expression and local toxicity induced by adjuvant intravesical therapy. J Urol, 2015. 193 (4S): e53

    Diagnostic accuracy of fecal calprotectin assay in distinguishing organic causes of chronic diarrhea from irritable bowel syndrome: a prospective study in adults and children

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    Fecal calprotectin (FC) has been proposed as a marker of inflammatory bowel disease (IBD), but few studies have evaluated its usefulness in patients with chronic diarrhea of various causes. We evaluated the diagnostic accuracy of a FC assay in identifying "organic" causes of chronic diarrhea in consecutive adults and children

    The effect of through-thickness compressive stress on mode II interlaminar fracture toughness

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    The effect of through-thickness compressive stress on mode II interlaminar fracture toughness is investigated experimentally and replicated numerically. The modified Transverse Crack Tensile specimen recently proposed by the authors is used, together with an experimental device designed to apply a constant transverse compressive stress on the surface of the specimen. Experiments are conducted using IM7/8552 specimens for different compressive stresses, ranging from 0 to 100 MPa, covering all the practical applications commonly encountered in the aeronautical industry (e.g., tightened filled holes or bolted joints). It is shown that mode II interlaminar fracture toughness increases with the applied compressive through-thickness stress. Finally, experiments are replicated using appropriate numerical models based on cohesive elements that take into account frictional effects. A good agreement between numerical predictions and experiments is found.Applied Mechanic

    Economic and environmental assessment of seed and rhizome propagated Miscanthus in the UK

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    Growth in planted areas of Miscanthus for biomass in Europe has stagnated since 2010 due to technical challenges, economic barriers and environmental concerns. These limitations need to be overcome before biomass production from Miscanthus can expand to several million hectares. In this paper we consider the economic and environmental effects of introducing seed based hybrids as an alternative to clonal M. x giganteus (Mxg). The impact of seed based propagation and novel agronomy was compared with current Mxg cultivation and used in ten commercially relevant, field scale experiments planted between 2012 and 2014 in the UK, Germany and Ukraine. Economic and greenhouse gas (GHG) emissions costs were quantified for the following production chain: propagation, establishment, harvest, transportation, storage and fuel preparation (excluding soil carbon changes). The production and utilisation efficiency of seed and rhizome propagation were compared. Results show that new hybrid seed propagation significantly reduces establishment cost to below ?900 ha-1. Calculated GHG emission costs for the seeds established via plugs, though relatively small, was higher than rhizomes because fossil fuels were assumed to heat glasshouses for raising seedling plugs (5.3 and 1.5 kg CO2 eq. C Mg (dry matter (DM))-1), respectively. Plastic mulch film reduced establishment time, improving crop economics. The breakeven yield was calculated to be 6 Mg DM ha-1 y-1, which is about half average UK yield for Mxg; with newer seeded hybrids reaching 16 Mg DM ha-1 in second year UK trials. These combined improvements will significantly increase crop profitability. The trade-offs between costs of production for the preparation of different feedstock formats show that bales are the best option for direct firing with the lowest transport costs (?0.04 Mg -1 km-1) and easy on-farm storage. However if pelleted fuel is required then chip harvesting is more economic. We show how current seed based propagation methods can increase the rate at which Miscanthus can be scaled up; ~x100 those of current rhizome propagation. These rapid ramp rates for biomass production are required to deliver a scalable and economic Miscanthus biomass fuel whose GHG emissions are ~1/20th those of natural gas per unit of heatpublishersversionPeer reviewe

    Breeding progress and preparedness for mass‐scale deployment of perennial lignocellulosic biomass crops switchgrass, miscanthus, willow and poplar

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    UK: The UK‐led miscanthus research and breeding was mainly supported by the Biotechnology and Biological Sciences Research Council (BBSRC), Department for Environment, Food and Rural Affairs (Defra), the BBSRC CSP strategic funding grant BB/CSP1730/1, Innovate UK/BBSRC “MUST” BB/N016149/1, CERES Inc. and Terravesta Ltd. through the GIANT‐LINK project (LK0863). Genomic selection and genomewide association study activities were supported by BBSRC grant BB/K01711X/1, the BBSRC strategic programme grant on Energy Grasses & Bio‐refining BBS/E/W/10963A01. The UK‐led willow R&D work reported here was supported by BBSRC (BBS/E/C/00005199, BBS/E/C/00005201, BB/G016216/1, BB/E006833/1, BB/G00580X/1 and BBS/E/C/000I0410), Defra (NF0424) and the Department of Trade and Industry (DTI) (B/W6/00599/00/00). IT: The Brain Gain Program (Rientro dei cervelli) of the Italian Ministry of Education, University, and Research supports Antoine Harfouche. US: Contributions by Gerald Tuskan to this manuscript were supported by the Center for Bioenergy Innovation, a US Department of Energy Bioenergy Research Center supported by the Office of Biological and Environmental Research in the DOE Office of Science, under contract number DE‐AC05‐00OR22725. Willow breeding efforts at Cornell University have been supported by grants from the US Department of Agriculture National Institute of Food and Agriculture. Contributions by the University of Illinois were supported primarily by the DOE Office of Science; Office of Biological and Environmental Research (BER); grant nos. DE‐SC0006634, DE‐SC0012379 and DE‐SC0018420 (Center for Advanced Bioenergy and Bioproducts Innovation); and the Energy Biosciences Institute. EU: We would like to further acknowledge contributions from the EU projects “OPTIMISC” FP7‐289159 on miscanthus and “WATBIO” FP7‐311929 on poplar and miscanthus as well as “GRACE” H2020‐EU.3.2.6. Bio‐based Industries Joint Technology Initiative (BBI‐JTI) Project ID 745012 on miscanthus.Peer reviewedPostprintPublisher PD
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