47 research outputs found

    X-Ray Photon Correlation Spectroscopy Reveals Intermittent Aging Dynamics in a Metallic Glass

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    We use coherent X-rays to probe the aging dynamics of a metallic glass directly on the atomic level. Contrary to the common assumption of a steady slowing down of the dynamics usually observed in macroscopic studies, we show that the structural relaxation processes underlying aging in this metallic glass are intermittent and highly heterogeneous at the atomic scale. Moreover, physical aging is triggered by cooperative atomic rearrangements, driven by the relaxation of internal stresses. The rich diversity of this behavior reflects a complex energy landscape, giving rise to a unique type of glassy-state dynamics.Comment: 5 pages, 4 figure

    Linguistic skills in bilingual children with developmental language disorders: A pilot study

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    The current pilot study compared the linguistic characteristics of a cohort of simultaneous bilingual children (Italian, L1; German L2) with developmental language disorders (DLDs) and those of bilingual peers with typical language development (TLD). Importantly, the two groups were balanced for a number of environmental variables (e.g., age of first exposure to the L2, acquisition contexts, degree of exposure to both languages) known to affect linguistic development in both TLD and DLDs. The analyses included the assessment of the participants\u2019 phonological short-term memory. Their lexical, grammatical and narrative abilities were analyzed in both languages by administering the Italian and German equivalent forms of the Battery for the assessment of language in children aged 4 to 12 \u2013 BVL_4-12 (Marini et al., 2015). The children with DLDs had reduced phonological short-term memory and lexical skills that, in turn, contributed to the reduced levels of local coherence and informativeness of their narratives. Such difficulties were found at similar levels in their two languages. These results suggest that reduced phonological short-term memory and lexical selection skills may reflect a core symptom in both mono- and bilingual children with developmental language disorders

    Microscopic evidence of the connection between liquid-liquid transition and dynamical crossover in an ultraviscous metallic glass former

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    Liquid-liquid transitions are interesting to many researchers since they occur in systems as diverse as monoatomic liquids, multicomponent oxides, and metallic glass formers. In some cases, the crossover is accompanied by changes in the dynamical properties. By combining state-of-the-art synchrotron techniques, we followed the structure and atomic motion during quasistatic cooling of the Au49Cu26.9Si16.3Ag5.5Pd2.3 metallic glass former from the low-temperature supercooled liquid. With this thermal protocol, we were able to lower the glass transition temperature far enough to reveal a liquid-liquid crossover between two amorphous structures corresponding to two ultraviscous liquids with different kinetic behavior. This transition is in competition with vitrification, which occurs at conventional cooling rates, and is accompanied by structural changes not affecting the average density. Our results provide a direct connection between polyamorphism and dynamical crossover, and an alternative case to add to the highly debated topic on the low-temperature divergence of the dynamics in supercooled liquids.Peer ReviewedPostprint (published version

    Disentangling structural and kinetic components of the {\alpha}-relaxation in supercooled metallic liquids

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    The particle motion associated to the {\alpha}-relaxation in supercooled liquids is still challenging scientists due to its difficulty to be probed experimentally. By combining synchrotron techniques, we found the existence of microscopic structure-dynamics relationships in Pt42.5Cu27Ni9.5P21 and Pd42.5Cu27Ni9.5P21 liquids which allows us to disentangle structural and kinetic contributions to the {\alpha}-process. While the two alloys show similar kinetic fragilities, their structural fragilities differ and correlate with the temperature dependence of the stretching parameter describing the decay of the density fluctuations. This implies that the evolution of dynamical heterogeneities in supercooled alloys is determined by the rigidity of the melt structure. We find also that the atomic motion not only reflects the topological order but also the chemical short-range order, which can lead to a surprising slowdown of the {\alpha}-process at the mesoscopic length scale. These results will contribute to the comprehension of the glass transition, which is still missing

    Disentangling structural and kinetic components of the α-relaxation in supercooled metallic liquids

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    The particle motion associated to the α-relaxation in supercooled liquids is still challenging scientists due to its difficulty to be probed experimentally. By combining synchrotron techniques, we report the existence of microscopic structure-dynamics relationships in Pt42.5Cu27Ni9.5P21 and Pd42.5Cu27Ni9.5P21 liquids which allows us to disentangle structural and kinetic contributions to the α-process. While the two alloys show similar kinetic fragilities, their structural fragilities differ and correlate with the temperature dependence of the stretching parameter describing the decay of the density fluctuations. This implies that the evolution of dynamical heterogeneities in supercooled alloys is determined by the rigidity of the melt structure. We find also that the atomic motion not only reflects the topological order but also the chemical short-range order, which can lead to a surprising slowdown of the αprocess at the mesoscopic length scale. These results will contribute to the comprehension of the glass transition, which is still missing

    Linguistic Skills in Bilingual Children With Developmental Language Disorders: A Pilot Study

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    The current pilot study compared the linguistic characteristics of a cohort of simultaneous bilingual children (Italian, L1; German L2) with developmental language disorders (DLDs) and those of bilingual peers with typical language development (TLD). Importantly, the two groups were balanced for a number of environmental variables (e.g., age of first exposure to the L2, acquisition contexts, degree of exposure to both languages) known to affect linguistic development in both TLD and DLDs. The analyses included the assessment of the participants’ phonological short-term memory. Their lexical, grammatical and narrative abilities were analyzed in both languages by administering the Italian and German equivalent forms of the Battery for the assessment of language in children aged 4 to 12 – BVL_4-12 (Marini et al., 2015). The children with DLDs had reduced phonological short-term memory and lexical skills that, in turn, contributed to the reduced levels of local coherence and informativeness of their narratives. Such difficulties were found at similar levels in their two languages. These results suggest that reduced phonological short-term memory and lexical selection skills may reflect a core symptom in both mono- and bilingual children with developmental language disorders

    Surgeons' perspectives on artificial intelligence to support clinical decision-making in trauma and emergency contexts: results from an international survey

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    Background Artificial intelligence (AI) is gaining traction in medicine and surgery. AI-based applications can offer tools to examine high-volume data to inform predictive analytics that supports complex decision-making processes. Time-sensitive trauma and emergency contexts are often challenging. The study aims to investigate trauma and emergency surgeons’ knowledge and perception of using AI-based tools in clinical decision-making processes. Methods An online survey grounded on literature regarding AI-enabled surgical decision-making aids was created by a multidisciplinary committee and endorsed by the World Society of Emergency Surgery (WSES). The survey was advertised to 917 WSES members through the society’s website and Twitter profile. Results 650 surgeons from 71 countries in five continents participated in the survey. Results depict the presence of technology enthusiasts and skeptics and surgeons' preference toward more classical decision-making aids like clinical guidelines, traditional training, and the support of their multidisciplinary colleagues. A lack of knowledge about several AI-related aspects emerges and is associated with mistrust. Discussion The trauma and emergency surgical community is divided into those who firmly believe in the potential of AI and those who do not understand or trust AI-enabled surgical decision-making aids. Academic societies and surgical training programs should promote a foundational, working knowledge of clinical AI

    Dolphin-WET—Development of a Welfare Evaluation Tool for Bottlenose Dolphins (Tursiops truncatus) under Human Care

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    Ensuring high standards of animal welfare is not only an ethical duty for zoos and aquariums, but it is also essential to achieve their conservation, education, and research goals. While for some species, animal welfare assessment frameworks are already in place, little has been done for marine animals under human care. Responding to this demand, the welfare committee of the European Association for Aquatic Mammals (EAAM) set up a group of experts on welfare science, cetacean biology, and zoo animal medicine across Europe. Their objective was to develop a comprehensive tool to evaluate the welfare of bottlenose dolphins (Tursiops truncatus), named Dolphin-WET. The tool encompasses 49 indicators that were either validated through peer review or management-based expertise. The first of its kind, the Dolphin-WET is a species-specific welfare assessment tool that provides a holistic approach to evaluating dolphin welfare. Inspired by Mellor’s Five Domains Model and the Welfare Quality®, its hierarchical structure allows for detailed assessments from overall welfare down to specific indicators. Through combining 37 animal-based and 12 resource-based indicators that are evaluated based on a two- or three-level scoring, the protocol offers a detailed evaluation of individual dolphins. This approach allows for regular internal monitoring and targeted welfare management, enabling caretakers to address specific welfare concerns effectively

    Molecular epidemiology of a hepatitis C virus epidemic in a haemodialysis unit: outbreak investigation and infection outcome

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    <p>Abstract</p> <p>Background</p> <p>HCV is a leading cause of liver chronic diseases all over the world. In developed countries the highest prevalence of infection is reported among intravenous drug users and haemodialysis (HD) patients. The present report is to identify the pathway of HCV transmission during an outbreak of HCV infection in a privately run haemodialysis (HD) unit in Italy in 2005.</p> <p>Methods</p> <p>Dynamics of the outbreak and infection clinical outcomes were defined through an ambi-directional cohort study. Molecular epidemiology techniques were used to define the relationships between the viral variants infecting the patients and confirm the outbreak. Risk analysis and auditing procedures were carried out to define the transmission pathway(s).</p> <p>Results</p> <p>Of the 50 patients treated in the HD unit 5 were already anti-HCV positive and 13 became positive during the study period (AR = 28.9%). Phylogenic analysis identified that, all the molecularly characterized incident cases (10 out of 13), were infected with the same viral variant of one of the prevalent cases. The multivariate analysis and the auditing procedure disclosed a single event of multi-dose vials heparin contamination as the cause of transmission of the infection in 11 out of the 13 incident cases; 2 additional incident cases occurred possibly as a result of inappropriate risk management.</p> <p>Discussion</p> <p>More than 30% of all HCV infections in developed countries results from poor application of standard precautions during percutaneous procedures. Comprehensive strategy which included: educational programmes, periodical auditing on standard precaution, use of single-dose vials whenever possible, prospective surveillance for blood-borne infections (including a system of prompt notification) and risk assessment/management dedicated staff are the cornerstone to contain and prevent outbreaks in HD</p> <p>Conclusions</p> <p>The outbreak described should serve as a reminder to HD providers that patients undergoing dialysis are at risk for HCV infection and that HCV may be easily transmitted whenever standard precautions are not strictly applied.</p

    ARIA 2016 : Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle

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    The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma and rhinitis and (3) to develop guidelines with all stakeholders that could be used globally for all countries and populations. ARIA-disseminated and implemented in over 70 countries globally-is now focusing on the implementation of emerging technologies for individualized and predictive medicine. MASK [MACVIA (Contre les Maladies Chroniques pour un Vieillissement Actif)-ARIA Sentinel NetworK] uses mobile technology to develop care pathways for the management of rhinitis and asthma by a multi-disciplinary group and by patients themselves. An app (Android and iOS) is available in 20 countries and 15 languages. It uses a visual analogue scale to assess symptom control and work productivity as well as a clinical decision support system. It is associated with an inter-operable tablet for physicians and other health care professionals. The scaling up strategy uses the recommendations of the European Innovation Partnership on Active and Healthy Ageing. The aim of the novel ARIA approach is to provide an active and healthy life to rhinitis sufferers, whatever their age, sex or socio-economic status, in order to reduce health and social inequalities incurred by the disease.Peer reviewe
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