510 research outputs found

    A wireless method to obtain the impedance from scattering parameters

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    The coaxial wire method is a common and appreciated choice to assess the beam coupling impedance (BCI) of an accelerator element. Nevertheless, the results obtained from wire measurements could be inaccurate due to the presence of the stretched conductive. The aim of this work is to establish a solid technique to obtain the BCI from electromagnetic simulations, without modifications of the device under test. In this framework, we identified a new relation to get the resistive wall beam coupling impedance of a circular chamber directly from the scattering parameters. Furthermore, a possible generalization of the method to arbitrary cross section geometries has been studied and validated with numerical simulations

    Protective effects of exosomes derived from lyophilized porcine liver against acetaminophen damage on HepG2 cells

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    Background: Recently, extracellular vesicles have come to the fore following their emerging role in cell communication, thanks to their ability to reach cells into the human body without dissipating their cargo, transferring biological active molecules, such as proteins, nucleic acids, lipids, etc. They appear as a promising tool in medicine, because of their capability to modulate cellular response in recipient cells. Moreover, a considerable number of publications suggests that exosome uptake is selective but not specific, and it can cross species and cell-type boundaries. This study aims to explore the potential role of porcine liver derived extracellular vesicles, exosomes in particular, to protect human cells from acute damage induced by acetaminophen. Methods: Extracellular vesicles were isolated from porcine lyophilized liver using polymer-based precipitation and a further enrichment was performed using affinity beads. The effects of obtained fractions, total extracellular vesicles and enriched extracellular vesicles, were assessed on human liver derived HepG2 cells. Cell growth and survival were tested, with MTT and area coverage analysis designed by us, as well as protein expression, with immunofluorescence and Western blot. Oxidative stress in live cells was also measured with fluorogenic probes. Results: After proving that porcine extracellular vesicles did not have a toxic effect on HepG2, quite the contrary total extracellular vesicle fraction improved cell growth, we investigated their protective capability with a preconditioning strategy in APAP-induced damage. EVs displayed not only the ability to strongly modulate cell survival responses, but they also were able to boost cell cycle progression. Conclusions: Extracellular vesicles derived from farm animal food derivatives are able to modulate human hepatic cell metabolism, also improving cell survival in a damaged context

    Intracrine endorphinergic systems in modulation of myocardial differentiation

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    A wide variety of peptides not only interact with the cell surface, but govern complex signaling from inside the cell. This has been referred to as an "intracrine" action, and the orchestrating molecules as "intracrines". Here, we review the intracrine action of dynorphin B, a bioactive end-product of the prodynorphin gene, on nuclear opioid receptors and nuclear protein kinase C signaling to stimulate the transcription of a gene program of cardiogenesis. The ability of intracrine dynorphin B to prime the transcription of its own coding gene in isolated nuclei is discussed as a feed-forward loop of gene expression amplification and synchronization. We describe the role of hyaluronan mixed esters of butyric and retinoic acids as synthetic intracrines, controlling prodynorphin gene expression, cardiogenesis, and cardiac repair. We also discuss the increase in prodynorphin gene transcription and intracellular dynorphin B afforded by electromagnetic fields in stem cells, as a mechanism of cardiogenic signaling and enhancement in the yield of stem cell-derived cardiomyocytes. We underline the possibility of using the diffusive features of physical energies to modulate intracrinergic systems without the needs of viral vector-mediated gene transfer technologies, and prompt the exploration of this hypothesis in the near future

    Epiphytic lichens of the sacred natural site "Bosco di Sant'Antonio" (Majella National Park - Abruzzo)

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    Sacred Natural Sites are relevant for biodiversity conservation, as in the case of forest sites that, across centuries, developed old growth structures and are now crucial for the conservation of epiphytic lichens and other specialized forest organisms. In this study, we investigated the epiphytic lichen flora of a small forest patch included in the Majella National Park (Abruzzo), whose old growth features and naturalness reflect its long lasting spiritual role that perfectly fits with the concept of Sacred Natural Site. Results revealed that the "Bosco di Sant'Antonio" hosts a rich and interesting epiphytic lichen flora, thus indicating the potential of this Sacred Natural Site for lichen conservation. Fifty-six species were found including two species newly recorded in Abruzzo, two red-listed species, and the sensitive species Lobaria pulmonaria. This study corroborates the hypothesis that sacred forest sites are relevant for the conservation of specialized epiphytic lichens. In particular, in the Italian forest landscape where old-growth stands are practically absent, sacred forest sites may provide unique old-growth structures and buffer anthropogenic disturbance

    How Prefrail Older People Living Alone Perceive Information and Communications Technology and What They Would Ask a Robot for : Qualitative Study

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    Background: In the last decade, the family system has changed significantly. Although in the past, older people used to live with their children, nowadays, they cannot always depend on assistance of their relatives. Many older people wish to remain as independent as possible while remaining in their homes, even when living alone. To do so, there are many tasks that they must perform to maintain their independence in everyday life, and above all, their well-being. Information and communications technology (ICT), particularly robotics and domotics, could play a pivotal role in aging, especially in contemporary society, where relatives are not always able to accurately and constantly assist the older person. Objective: The aim of this study was to understand the needs, preferences, and views on ICT of some prefrail older people who live alone. In particular, we wanted to explore their attitude toward a hypothetical caregiver robot and the functions they would ask for. Methods: We designed a qualitative study based on an interpretative phenomenological approach. A total of 50 potential participants were purposively recruited in a big town in Northern Italy and were administered the Fried scale (to assess the participants\u2019 frailty) and the Mini-Mental State Examination (to evaluate the older person\u2019s capacity to comprehend the interview questions). In total, 25 prefrail older people who lived alone participated in an individual semistructured interview, lasting approximately 45 min each. Overall, 3 researchers independently analyzed the interviews transcripts, identifying meaning units, which were later grouped in clustering of themes, and finally in emergent themes. Constant triangulation among researchers and their reflective attitude assured trustiness. Results: From this study, it emerged that a number of interviewees who were currently using ICT (ie, smartphones) did not own a computer in the past, or did not receive higher education, or were not all young older people (aged 65-74 years). Furthermore, we found that among the older people who described their relationship with ICT as negative, many used it in everyday life. Referring to robotics, the interviewees appeared quite open-minded. In particular, robots were considered suitable for housekeeping, for monitoring older people\u2019s health and accidental falls, and for entertainment. Conclusions: Older people\u2019s use and attitudes toward ICT does not always seem to be related to previous experiences with technological devices, higher education, or lower age. Furthermore, many participants in this study were able to use ICT, even if they did not always acknowledge it. Moreover, many interviewees appeared to be open-minded toward technological devices, even toward robots. Therefore, proposing new advanced technology to a group of prefrail people, who are self-sufficient and can live alone at home, seems to be feasible

    Coupling Impedance of the CERN SPS beam position monitors

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    A detailed knowledge of the beam coupling impedance of the CERN Super Proton Synchrotron (SPS) is required in order to operate this machine with a higher intensity for the foreseen Large Hadron Collider (LHC) luminosity upgrade. A large number of Beam Position Monitors (BPMs) is currently installed in the SPS, and this is why their contribution to the SPS impedance has to be assessed. This paper focuses on electromagnetic (EM) simulations and bench measurements of the longitudinal and transverse impedance generated by the horizontal and vertical BPMs installed in the SPS machine

    Experimenting clinical pathways in general practice: a focus group investigation with Italian General Practitioners

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    Background. Clinical governance is considered crucial in primary care. Since 2005, clinical pathways have been experimentally implemented at the Local Health Authority of Monza Brianza (ASLMB), Italy, to develop general practitioners\u2019 (GPs) care of patients affected by some chronic diseases. The experimentation was aimed at introducing clinical governance in primary care, increasing GPs\u2019 involvement in the care of their patients, and improving both patients\u2019 and professionals\u2019 satisfaction. In the period 2005-2006, 12% of the 763 employed GPs in the ASLMB were involved in the experiment, while this percentage increased to 15-20% in 2007-2008. Design and Methods. Twenty-four GPs were purposively sampled, randomly divided into two groups and asked to participate in focus groups (FGs) held in 2008, aimed at evaluating their perception of the experiment. The FGs were audio-recorded, dialogues were typed out and undergone to a thematic analysis, according to the Interpretative Phenomenological Approach. Results. Four major themes emerged: i) clinical pathways can result in GPs working in a more efficient and effective fashion; ii) they can assure higher levels of both patient and professional satisfaction, since they sustain a caring approach and strengthen the GPs\u2019 role; iii) nevertheless, clinical pathways increase the bureaucratic workload and problems can arise in relationships among GPs and the LHA; iv) the implementation of clinical pathways can be improved, especially by reducing bureaucracy and by assuring their continuity. Conclusions. Managerial aspects should be considered with care in order to experimentally introduce clinical pathways in general practice, and continuity of the experimentation should be guaranteed to improve GPs\u2019 adherence and commitment

    eXeRCISeS FOR PAReTIC UPPeR LIMb AFTeR STROKe: A COMbINeD VIRTUAL-ReALITY AND TeLeMeDICINe APPROACH

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    Objective: Telerehabilitation enables a remotely controlled programme to be used to treat motor deficits in post-stroke patients. The effects of this telerehabilitation approach were compared with traditional motor rehabilitation methods. Design: Randomized single-blind controlled trial. Patients: A total of 36 patients with mild arm motor impairments due to ischaemic stroke in the region of the middle cerebral artery. Methods: The experimental treatment was a virtual realitybased system delivered via the Internet, which provided motor tasks to the patients from a remote rehabilitation facility. The control group underwent traditional physical therapy for the upper limb. Both treatments were of 4 weeks duration. All patients were assessed one month prior to therapy, at the commencement and termination of therapies and one month post-therapy, with the Fugl-Meyer Upper Extremity, the ABILHAND and the Ashworth scales. Results: Both rehabilitative therapies significantly improved all outcome scores after treatment, but only the Fugl-Meyer Upper Extremity scale showed differences in the comparison between groups. Conclusion: Both strategies were effective, but the experimental approach induced better outcomes in motor performance. These results may favour early discharge from hospital sustained by a telerehabilitation programme, with potential beneficial effects on the use of available resources

    Hybrid photonic-bandgap accelerating cavities

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    In a recent investigation, we studied two-dimensional point-defected photonic bandgap cavities composed of dielectric rods arranged according to various representative periodic and aperiodic lattices, with special emphasis on possible applications to particle acceleration (along the longitudinal axis). In this paper, we present a new study aimed at highlighting the possible advantages of using hybrid structures based on the above dielectric configurations, but featuring metallic rods in the outermost regions, for the design of extremely-high quality factor, bandgap-based, accelerating resonators. In this framework, we consider diverse configurations, with different (periodic and aperiodic) lattice geometries, sizes, and dielectric/metal fractions. Moreover, we also explore possible improvements attainable via the use of superconducting plates to confine the electromagnetic field in the longitudinal direction. Results from our comparative studies, based on numerical full-wave simulations backed by experimental validations (at room and cryogenic temperatures) in the microwave region, identify the candidate parametric configurations capable of yielding the highest quality factor.Comment: 13 pages, 5 figures, 3 tables. One figure and one reference added; minor changes in the tex
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