916 research outputs found

    EFFICIENT SIMULATION TOOL TO CHARACTERIZE THE RADAR CROSS SECTION OF A PEDESTRIAN IN NEAR FIELD

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    none4A simulation tool to characterize the radar cross section of a pedestrian in near field is presented in the paper. The tool has been developed in order to predict and optimize the performance of the short-range radar systems employed in autonomous vehicle operations. It is based on an analytical model which joins the modeling of the human body with the theory of the physical optics. Our studies first focused on the implementation of the electromagnetic code where the human body, the radiation properties of the antenna and the scenario to be analyzed have been analytically expressed. Then, the proposed model has been validated in terms of accuracy comparing simulated and experimental data regarding the radar cross section of a metal sphere and of an adult, in the frequency range 23-28 GHz. In the end, an evaluation of the performance in terms of required computer memory and execution time has been carried out, comparing the proposed simulation tool with other numerical computational methods.openManfredi, Giovanni; Russo, Paola; De Leo, Alfredo; Cerri, GrazianoManfredi, Giovanni; Russo, Paola; De Leo, Alfredo; Cerri, Grazian

    Wireless Sensing for the Respiratory Activity of Human Beings: Measurements and Wide-band Numerical Analysis

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    An electromagnetic sensing system for the measurement of the respiratory activity is presented. The aims are to demonstrate the feasibility of the proposed approach and in particular to evaluate the effect on the measured signal of the distance between the subject and the sensing apparatus. Moreover, an electromagnetic model of the system, including the monitored subject, is proposed as a tool to solve the problem of selecting working parameters for system design. The sensing system is based on the measurement of the phase variation of the reflection coefficient caused by the respiratory activity. The phase signal compared with the thorax displacement measured by a reference instrument shows a high correlation () for different subject postures (sitting, standing, and lying) and a reduction of the signal amplitude with the distance  dB/cm is reported. The numerical simulations performed on a wide-band highlight the frequencies where the method exhibits the highest sensitivity to thorax movements. The sensitivity can be further improved by reducing the antenna beamwidth. Despite the signal amplitude reduction, the proposed system makes it possible to correctly operate at distances up to 2.5 m

    Statistical techniques applied to the automatic diagnosis of dermoscopic images

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    An image based system implementing a well‐known diagnostic method is disclosed for the automatic detection of melanomas as support to clinicians. The software procedure is able to recognize automatically the skin lesion within the digital image, measure morphological and chromatic parameters, carry out a suitable classification for the detection of structural dermoscopic criteria provided by the 7‐Point Check. Original contribution is referred to advanced statistical techniques, which are introduced at different stages of the image processing, including the border detection, the extraction of low‐level features and scoring of high order features (namely dermoscopic criteria). The proposed approach is experimentally tested with reference to a large image set of pigmented lesions

    Second Harmonic Generation Enabled by Longitudinal Electric Field Components in Photonic Wire Waveguides

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    We investigate type I second harmonic generation in III-V semiconductor wire waveguides aligned with a crystallographic axis. In this direction, because of the single nonzero tensor element of III-V semiconductors, only frequency conversion by mixing with the longitudinal components of the optical fields is allowed. We experimentally study the impact of the propagation direction on the conversion efficiency and confirm the role played by the longitudinal components through the excitation of an antisymmetric second harmonic higher order mode

    Development of a Novel Medical Device for Mucositis and Peri-Implantitis Treatment

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    In spite of all the developments in dental implantology techniques, peri-implant diseases are frequent (prevalence up to 80% and 56% of subjects for mucositis and peri-implantitis, respectively) and there is an urgency for an effective treatment strategy. This paper presents an innovative electromedical device for the electromagnetic treatment of mucositis and peri-implantitis diseases. This device is also equipped with a measurement part for bioimpedance, which reflects the health conditions of a tissue, thus allowing clinicians to objectively detect impaired areas and to monitor the severity of the disease, evaluate the treatment efficacy, and adjust it accordingly. The design of the device was realized considering literature data, clinical evidence, numerical simulation results, and electromagnetic compatibility (EMC) pre-compliance tests, involving both clinicians and engineers, to better understand all the needs and translate them into design requirements. The reported system is being tested in more than 50 dental offices since 2019, providing efficient treatments for mucositis and peri-implantitis, with success rates of approximately 98% and 80%, respectively

    QUADRUPLE RESCUE THERAPY AFTER FIRST AND SECOND LINE FAILURE FOR HELICOBACTER PYLORI TREATMENT: COMPARISON BETWEEN TWO TETRACYCLINE-BASED REGIMENS

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    Background & Aims: Antibiotic resistance is the main reason for failure of Helicobacter pylori (H. pylori) treatment. Currently, guidelines recommend a treatment guided by antimicrobial susceptibility testing after two failures. However, microbial culture is not feasible everywhere, and the limited number of effective antibiotics against the bacterium narrows the options; thus a rescue therapy combining antibiotics with a low resistance may be fitting. Methods: Patients who have failed a first-line treatment (either prolonged triple or sequential regimens) and, successively, a levofoxacin-based triple therapy were considered for the study. Subjects underwent urea breath test (UBT), stool antigen test (ST) and endoscopy/histology to confirm the diagnosis. Cytopenia and impaired liver and kidney function were exclusion criteria. Fify-four subjects were randomized 1:1 to two regimens: RMB abeprazole/Rifabutin/Minocycline/Bismuth sub-citrate or MTB Rabeprazole/Tinidazole/ Minocycline/Bismuth sub-citrate both for 10 days. Te results were checked 6 weeks afer the end of therapy with ST/UBT plus endoscopy when indicated. Results: RMB eradicated the bacterium in 21 patients. Two subjects dropped out. Te eradication rate was 77.7% (CI 62.0-93.4%) at intention-to-treat and 84.0% (CI 69.6-98.4%) at per-protocol analysis. MTB was successful in 14 patients (51.9%, CI 33.1-70.7%). No patient withdrew from the treatment for adverse events. Drug-related side effects were reported only in 3 subjects, but in all cases the treatment was carried on. Conclusions: Te association minocycline/rifabutin seems to have a synergic effect and a good therapeutic outcome in patients who have failed at least two previous regimens, although a trial on a large population is needed

    Efficient Type II Second Harmonic Generation in an Indium Gallium Phosphide on insulator wire waveguide aligned with a crystallographic axis

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    We theoretically and experimentally investigate type II second harmonic generation in III-V-on-insulator wire waveguides. We show that the propagation direction plays a crucial role and that longitudinal field components can be leveraged for robust and efficient conversion. We predict that the maximum theoretical conversion is larger than that of type I second harmonic generation for similar waveguide dimensions and reach an experimental conversion efficiency of 12 %/W, limited by the propagation loss

    In vivo Overexpression of Electrogenic Sodium/Bicarbonate Cotransporter (NBCe1) by AAV9 Modifies the Cardiac Action Potential and the QT Interval in Mice

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    Cardiac cells depend on specific sarcolemmal ion transporters to assure the correct intracellular pH regulation. The sodium/bicarbonate cotransporter (NBC) is one of the major alkalinizing mechanisms. In the heart two different NBC isoforms have been described: the electroneutral NBCn1 (1Na+:1 (Formula presented.)) and the electrogenic NBCe1 (1Na+:2 (Formula presented.)). NBCe1 generates an anionic repolarizing current that modulates the action potential duration (APD). In addition to regulating the pH, the NBC is a source of sodium influx. It has been postulated that NBC could play a role in the development of hypertrophy. The aim of this research was to study the contribution of NBCe1 in heart electrophysiology and in the development of heart hypertrophy in an in vivo mouse model with overexpression of NBCe1. Heart NBCe1 overexpression was achieved by a recombinant cardiotropic adeno-associated virus (AAV9) and was evidenced by western-blot and qPCR. AAV9-mCherry was used as a transduction control. NBCe1 overexpression fails to increase heart growth. Patch clamp and electrocardiogram were performed. We observed a reduction on both, ventricular myocytes APD and electrocardiogram QT interval corrected by cardiac rate, emphasizing for the first time NBCe1 relevance for the electrical activity of the heart.Fil: Di Mattia, Romina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Diaz Zegarra, Leandro Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Valverde, Carlos Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Blanco, Paula Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Centro de Fisiología Reproductiva y Métodos Complementarios de Diagnóstico; ArgentinaFil: Jaquenod de Giusti, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Portiansky, Enrique Leo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Cátedra de Patología General Veterinaria; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Aiello, Ernesto Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Orlowski, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; Argentin

    BRS 277: Wheat cultivar

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    The wheat cultivar ‘BRS 277’ was developed by Embrapa (Empresa Brasileira de Pesquisa Agropecuária),resulting from a cross between OR1 and Coker 97-33. The plant height of ‘BRS 277’ is short, frost resistance in the vegetativestage is good and resistance to leaf rust moderate
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