203 research outputs found

    Mobile Sound Recognition for the Deaf and Hard of Hearing

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    Human perception of surrounding events is strongly dependent on audio cues. Thus, acoustic insulation can seriously impact situational awareness. We present an exploratory study in the domain of assistive computing, eliciting requirements and presenting solutions to problems found in the development of an environmental sound recognition system, which aims to assist deaf and hard of hearing people in the perception of sounds. To take advantage of smartphones computational ubiquity, we propose a system that executes all processing on the device itself, from audio features extraction to recognition and visual presentation of results. Our application also presents the confidence level of the classification to the user. A test of the system conducted with deaf users provided important and inspiring feedback from participants.Comment: 25 pages, 8 figure

    A gain-scheduled PID controller for propofol dosing in anesthesia

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    6siA gain-scheduled proportional-integral-derivative controller is proposed for the closed-loop dosing of propofol in anesthesia (with the bispectral index as a controlled variable). In particular, it is shown that a different tuning of the parameters should be used during the infusion and maintenance phases. Further, the role of the noise filter is investigated.nonenonePadula, F.; Ionescu, C.; Latronico, N.; Paltenghi, M.; Visioli, A.; Vivacqua, G.Padula, Fabrizio; Ionescu, C.; Latronico, Nicola; Paltenghi, M.; Visioli, Antonio; Vivacqua, Giuli

    Extensive solitary lymphatic malformation of the liver in a child: a case report and literature review

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    Intrabdominal lymphatic malformations are rare benign congenital vascular anomalies that account for less than 5% of benign masses in childhood, with an extremely variable clinical presentation. For this reason, although their radiological appearance is usually typical, diagnosis can be challenging and not always immediate. This report describes a unique case of extensive solitary hepatic lymphatic malformation in a 10-year-old boy with both extra- and intraparenchymal development with no associated symptoms. A literature review of reported cases of solitary hepatic lymphatic malformation is also included

    Bergen metrics: composite error metrics for assessing performance of climate models using EURO-CORDEX simulations

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    Error metrics are useful for evaluating model performance and have been used extensively in climate change studies. Despite the abundance of error metrics in the literature, most studies use only one or two metrics. Since each metric evaluates a specific aspect of the relationship between the reference data and model data, restricting the comparison to just one or two metrics limits the range of insights derived from the analysis. This study proposes a new framework and composite error metrics called Bergen metrics to summarize the overall performance of climate models and to ease interpretation of results from multiple error metrics. The framework of Bergen metrics are based on the p norm, and the first norm is selected to evaluate the climate models. The framework includes the application of a non-parametric clustering technique to multiple error metrics to reduce the number of error metrics with minimum information loss. An example of Bergen metrics is provided through its application to the large ensemble of regional climate simulations available from the EURO-CORDEX initiative. This study calculates 38 different error metrics to assess the performance of 89 regional climate simulations of precipitation and temperature over Europe. The non-parametric clustering technique is applied to these 38 metrics to reduce the number of metrics to be used in Bergen metrics for eight different sub-regions in Europe. These provide useful information about the performance of the error metrics in different regions. Results show it is possible to observe contradictory behaviour among error metrics when examining a single model. Therefore, the study also underscores the significance of employing multiple error metrics depending on the specific use case to achieve a thorough understanding of the model behaviour.</p

    Analysis of screw feeding of faceted particles by discrete element method

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    Reliable and consistent powder flow in screw feeders is of great interest to a wide range of industries, particularly for continuous manufacturing of pharmaceutical powders. However, analysis of flow of cohesive powders with sharp corners and edges, as commonly found in the case of crystalline solids, presents a great challenge due to complexity of shape and its influence on flow. In the present work, the influence of particle shape and cohesion on phenomena such as cohesive arching in hoppers and screw feeder pitches is analysed by numerical simulations using the Discrete Element Method, and their impact on the outlet mass flow rate is evaluated. Faceted and spherical particles with different cohesion levels are generated and allowed to settle in a hopper on top of a screw feeder. The screw is then rotated, thus feeding the particles through the barrel. Particle interactions are analysed numerically for the hopper region, a predominantly slow-flow regime, and for the pitches of the screw feeder, where a speed-dependent regime prevails. Paracetamol crystal shape is taken as a model faceted shape. Its parameters such as the coefficients of restitution and friction, needed for the simulations, are calibrated by experimental work. Transient arching occurs as the level of cohesion is increased. The frequency of formation and collapse of arches within the hopper region increases, and eventually, permanent arching is observed. Analysis of stress and strain rate in the screw barrel region shows that the shear stress is a weak function of the shear rate with a power index of around 0.3, which is independent of particle shape. The flow rate is influenced considerably by particle shape, whilst increased cohesion causes an increase in void fraction and affects transient arching

    The emerging role of ferroptosis in liver cancers

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    : Liver cancer represents a global health challenge with worldwide growth. Hepatocellular carcinoma (HCC) is the most common type of liver cancer. Indeed, approximately 90% of HCC cases have a low survival rate. Moreover, cholangiocarcinoma (CC) is another malignant solid tumor originating from cholangiocytes, the epithelial cells of the biliary system. It is the second-most common primary liver tumor, with an increasing course in morbidity and mortality. Tumor cells always show high metabolic levels, antioxidant modifications, and an increased iron uptake to maintain unlimited growth. In recent years, alterations in iron metabolism have been shown to play an important role in the pathogenesis of HCC. Several findings show that a diet rich in iron can enhance HCC risk. Hence, elevated iron concentration inside the cell may promote the development of HCC. Growing evidence sustains that activating ferroptosis may potentially block the proliferation of HCC cells. Even in CC, it has been shown that ferroptosis plays a crucial role in the treatment of tumors. Several data confirmed the inhibitory effect in cell growth of photodynamic therapy (PDT) that can induce reactive oxygen species (ROS) in CC, leading to an increase in malondialdehyde (MDA) and a decrease in intracellular glutathione (GSH). MDA and GSH depletion/modulation are crucial in inducing ferroptosis, suggesting that PDT may have the potential to induce this kind of cell death through these ways. A selective induction of programmed cell death in cancer cells is one of the main treatments for malignant tumors; thus, ferroptosis may represent a novel therapeutic strategy against HCC and CC

    DEM analysis of the effect of particle shape, cohesion and strain rate on powder rheometry

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    Discrete Element Method (DEM) is used to simulate the flow of particles addressing the influence of shear strain rate, particle shape and cohesion on the flow characteristics. For this purpose, the dynamics of particle motion in the Freeman Technology FT4 rheometer is analysed. The simulations are first validated by comparison with experiments with cohesive particles, i.e. silanised glass beads, from the literature. Particles with faceted shapes, sharp corners and edges are then simulated and found to require significantly higher energy to flow compared to spherical particles. The presence of truncated vertices, typical of active pharmaceutical ingredients, influences the flow behaviour drastically. The results of this analysis therefore reveal the importance of considering the actual particle shape in DEM simulations when faceted particles are considered. Finally, a rheological model describing the relationship between the dimensionless shear stress and the inertial number for several particle shapes, cohesion values and blade tip speeds is proposed. The outcome of this study may lead to a unified rheological description of powder flow, which incorporates the effect of cohesion, shape and shear strain rate
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