2,441 research outputs found

    Efficient Analysis for the Design Refinement of Large Multilayered Printed Reflectarrays

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    In this paper, we present an efficient numerical technique for the analysis of a reflectarray and its design refinement by the characterization of the “actual” influence of each radiating element when embedded in the antenna structure. The method makes use of the MLayAIM, a fast full-wave formulation suitable for the analysis of electrically large multilayered printed arrays which have one or more planar metallizations and vertical conductors. The low numerical complexity of the analysis method allows the development of a recursive procedure that, starting from the equivalent currents relevant to each cell of the reflectarray when this is immersed in the actual antenna layout, calculates the real phase-shift introduced by each radiating element and corrects its dimensions to better fit the antenna requirements

    The Facial Unreasonableness Theory: Filling the Void Between Per Se and Rule of Reason

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    Attenuating surface gravity waves with mechanical metamaterials

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    4noMetamaterials and photonic/phononic crystals have been successfully developed in recent years to achieve advanced wave manipulation and control, both in electromagnetism and mechanics. However, the underlying concepts are yet to be fully applied to the field of fluid dynamics and water waves. Here, we present an example of the interaction of surface gravity waves with a mechanical metamaterial, i.e., periodic underwater oscillating resonators. In particular, we study a device composed of an array of periodic submerged harmonic oscillators whose objective is to absorb wave energy and dissipate it inside the fluid in the form of heat. The study is performed using a state-of-the-art direct numerical simulation of the Navier-Stokes equation in its two-dimensional form with free boundary and moving bodies. We use a volume of fluid interface technique for tracking the surface and an immersed boundary method for the fluid-structure interaction. We first study the interaction of a monochromatic wave with a single oscillator and then add up to four resonators coupled only fluid-mechanically. We study the efficiency of the device in terms of the total energy dissipation and find that by adding resonators, the dissipation increases in a nontrivial way. As expected, a large energy attenuation is achieved when the wave and resonators are characterized by similar frequencies. As the number of resonators is increased, the range of attenuated frequencies also increases. The concept and results presented herein are of relevance for coastal protection applications.openpartially_openembargoed_20220426De Vita F.; De Lillo F.; Bosia F.; Onorato M.De Vita, F.; De Lillo, F.; Bosia, F.; Onorato, M

    Healthcare and economic burden of ANCA-associated vasculitis in Italy: an integrated analysis from clinical and administrative databases

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    ANCA-associated vasculitides (AAV) comprise a group of systemic vasculitides characterized by inflammation of small-sized blood vessels leading to multi-organ involvement. The worldwide annual incidence of AAV ranges from 1.2 to 3.3 cases per 100 000 individuals with a prevalence of 4.6\u201342.1 cases per 100 000 individuals. The prevalence of AAV is geographically heterogeneous; therefore, regional epidemiological studies can be more informative to improve health care systems. Even though clinicians are aware that the healthcare burden and the risk of hospitalization of AAV appear high, data on hospitalization and cost of illness due to AAV are still scarce or even lacking. This study aims to characterize the economic burden of AAV in Friuli Venezia Giulia (FVG), Italy. Thus, a retrospective study was conducted through the integration of many administrative health databases of the FVG as the source of information. From data integration, we estimated that more than two-thirds of AAV patients showed at least one hospitalization in their medical history, most frequently caused by the disease itself or superimposed infections. Around 10% of patients developed end-stage renal disease. In an 8-year follow-up, the overall healthcare cost was \u20ac 1,215,078, corresponding to \u20ac 6,168 patient-year. ANCA-positive patients showed much higher costs than ANCA-negative patients did. Overall, AAV are rare diseases, but imply very high healthcare costs. Early diagnosis and optimal treatment probably still remain unmet needs for AAV

    Maintenance bevacizumab beyond first-line paclitaxel plus bevacizumab in patients with Her2-negative hormone receptor-positive metastatic breast cancer. Efficacy in combination with hormonal therapy

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    Background: Data on efficacy of bevacizumab (B) beyond first-line taxane -including regimen (BT) as first-line treatment are lacking. Although preclinical results that anti-angiogenic agents combined with hormonal therapy (HT) could be active, no clinical data exist about combination of maintenance Bevacizumab (mBev) with HT.Methods: Thirty-five patients who experienced a response after first-line BT, were given mBev at the dose of 15 mg/kg every 3 weeks. Among 30 pts with hormonal receptor-positive metastatic breast cancer (MBC), 20 (66.6%) received HT with mBev (mHTBev). Objective of the study was the outcome and safety of mBev and in two groups of patients receiving HT or not.Results: Complete response and partial response was achieved/maintained in 4 (11.4%) and 13 (37.1%) patients, respectively (overall response rate: 48.5%). Clinical benefit was obtained on 23 patients (65.7%). Median of mBev PFS and clinical benefit were 6.8 months (95% CI: 0.8-12.7) and 17.1 months (95% CI :12.2-21.9), respectively. Median PFS of patients who received mHTBev was longer than mBev without HT (13 months and 4.1 months, respectively, p = 0.05). The most common severe toxicities were proteinuria (11.4%) and hypertension (8.5%). No additional toxicity was observed with HTBev.Conclusion: Maintenance bevacizumab with or without anti-hormonal therapy in patients with hormone receptor positive breast cancer is tolerable and associated with long-term clinical outcome; these results encourage the strategy of prolonging bevacizumab until progression in combination with anti-hormonal agents

    Seasonal and event-based hydrological and slope stability modeling of pyroclastic fall deposits covering slopes in Campania (Southern Italy)

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    The pyroclastic fall deposits mantling mountain slopes in the Campania region (Southern Italy) represent one of the most studied geomorphological frameworks of the world regarding rainfall-induced debris flows threating urban areas. The proposed study focused on advancing knowledge about the hydrological response of pyroclastic fall coverings from the seasonal to event-based time scales, leading to the initiation of slope instability. The study was based on two consequential tasks. The first was the analysis of a six-year monitoring of soil pressure head carried out in a sample area of the Sarno Mountains, located above a debris flow initiation zone. The second was based on coupled hydrological and slope stability modeling performed on the physical models of slopes, which were reconstructed by empirical correlations between the slope angle, total thickness, and stratigraphic settings of pyroclastic fall deposits mantling slopes. The results obtained were: (a) The understanding of a soil pressure head regime of the volcaniclastic soil mantle, always ranging in unsaturated conditions and characterized by a strong seasonal variability depending on precipitation patterns and the life cycle of deciduous chestnut forest; and (b) the reconstruction through a deterministic approach of seasonal intensity-duration rainfall thresholds related to different morphological conditions

    Enabling QM-accurate simulation of dislocation motion in γ−Ni and α−Fe using a hybrid multiscale approach

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    We present an extension of the ‘learn on the fly’ method to the study of the motion of dislocations in metallic systems, developed with the aim of producing information-efficient force models that can be systematically validated against reference QM calculations. Nye tensor analysis is used to dynamically track the quantum region centered at the core of a dislocation, thus enabling quantum mechanics/molecular mechanics simulations. The technique is used to study the motion of screw dislocations in Ni-Al systems, relevant to plastic deformation in Ni-based alloys, at a variety of temperature/strain conditions. These simulations reveal only a moderate spacing ( ∌ 5 Å ) between Shockley partial dislocations, at variance with the predictions of traditional molecular dynamics (MD) simulation using interatomic potentials, which yields a much larger spacing in the high stress regime. The discrepancy can be rationalized in terms of the elastic properties of an hcp crystal, which influence the behavior of the stacking fault region between Shockley partial dislocations. The transferability of this technique to more challenging systems is addressed, focusing on the expected accuracy of such calculations. The bcc α − Fe phase is a prime example, as its magnetic properties at the open surfaces make it particularly challenging for embedding-based QM/MM techniques. Our tests reveal that high accuracy can still be obtained at the core of a dislocation, albeit at a significant computational cost for fully converged results. However, we find this cost can be reduced by using a machine learning approach to progressively reduce the rate of expensive QM calculations required during the dynamical simulations, as the size of the QM database increases

    Salicylic acid for the treatment of melasma: new acquisitions for monitoring the clinical improvement.

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    OBJECTIVE: The Melasma Area and Severity Index (MASI) and the Melasma Severity Score (MSS) are calculated on the basis of only a subjective clinical assessment. This raises the need to have an objective score, uniform in the evaluation by different clinicians. The purpose of this study was to establish if the images by Canfield Reveal Imager can be correlated to MASI score to better evaluate the clinical efficacy of salicylic acid 33% peeling in the treatment of melasma respect to the clinical observation. METHODS: The study was a voluntary observational study. Twenty female patients affected with melasma, aged between 30 and 60 years, were included in the study. Treatment with salicylic acid 33% was performed once a month, for a total of four times. The dermatologist (Doc A) examined each patient's melasma areas using MASI score, at the face-to-face observation and at Reveal images evaluation during the first (T0) and the end point time (T4). Digital photographs were also evaluated by another experienced dermatologist (Doc B), who has never seen clinically the patients before and who evaluated MASI score by Reveal images at time T0 and T4. RESULTS: Student's t-test and linear regression test were performed, showing statistically significant values comparing MASI score obtained by digital photo and MASI score obtained clinically. CONCLUSION: The monitoring of the improvement by Reveal images can optimize the treatment approach and the efficacy of same dermocosmetics procedures can be revised following standard criteria

    Fast analysis of large finite arrays with a combined multiresolution-SM/AIM approach

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    We present a synthesis of the sparse matrix/adaptive integral method (SM/AIM) and the multiresolution (MR) approach for the analysis of electrically large finite arrays, with planar or 3-D radiating elements; the two methods were separately introduced previously. The use of the MR has the effect of a preconditioner and speeds up the convergence rate of the SM/AIM of almost two orders of magnitude, with a total reduction of the numerical complexity with respect to the standard MoM of almost three orders of magnitude

    Polyphenol oxidase genes as integral part of the evolutionary history of domesticated tetraploid wheat.

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    Abstract Studying and understanding the genetic basis of polyphenol oxidases (PPO)-related traits plays a crucial role in genetic improvement of crops. A tetraploid wheat collection ( T. turgidum ssp., TWC) was analyzed using the 90K wheat SNP iSelect assay and phenotyped for PPO activity. A total of 21,347 polymorphic SNPs were used to perform genome-wide association analysis (GWA) in TWC and durum wheat sub-groups, detecting 23 and 85 marker-trait associations (MTA). In addition, candidate genes responsible for PPO activity were predicted. Based on the 23 MTAs detected in TWC, two haplotypes associated with low and high PPO activity were identified. Four SNPs were developed and validated providing one reliable marker (IWB75732) for marker assisted selection. The 23 MTAs were used to evaluate the genetic divergence ( FST > 0.25) between the T. turgidum subspecies , providing new information important for understanding the domestication process of Triticum turgidum ssp. and in particular of ssp. carthlicum
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