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The objective of this work is to propose a standard classification of seismic signals generated by gravitational processes and detected at close distances ( km). We review the studies where seismic instruments have been installed on unstable slopes and discuss the choice of the seismic instruments and the network geometries. Seismic observations acquired at 13 unstable slopes are analyzed in order to construct the proposed typology. The selected slopes are affected by various landslide types (slide, fall, topple and flow) triggered in various material (from unconsolidated soils to consolidated rocks). We investigate high-frequency bands (>1 Hz) where most of the seismic energy is recorded at the 1 km sensor to source distances. Several signal properties (duration, spectral content and spectrogram shape) are used to describe the sources. We observe that similar gravitational processes generate similar signals at different slopes. Three main classes can be differentiated mainly from the length of the signals, the number of peaks and the duration of the autocorrelation. The classes are the “slopequake” class, which corresponds to sources potentially occurring within the landslide body; the “rockfall” class, which corresponds to signals generated by rock block impacts; and the “granular flow” class, which corresponds to signals generated by wet or dry debris/rock flows. Subclasses are further proposed to differentiate specific signal properties (frequency content, resonance, precursory signal). The signal properties of each class and subclass are described and several signals of the same class recorded at different slopes are presented. Their potential origins are discussed. The typology aims to serve as a standard for further comparisons of the endogenous microseismicity recorded on landslides.

We describe in this paper different improvements that were brought to the installation of seismic broadband stations deployed by the Observatoire de Grenoble (OSUG) in the northern French Alps. This work was realized in the frame of a French-Italian ALCOTRA project (RISE), aimed at modernizing the broadband seismic networks across our common border. We had the opportunity with this project to improve some of our seismic recording sites, both in term of sensor installation quality, and in term of reliability. We detail in particular the thermal and barometric protection system that we designed and show its effect on the reduction of long period noise above 20 s.

In this article we propose a new design methodology allowing us to control both amplitude and phase of electromagnetic waves from a cylindrical incident wave. This results in isotropic materials and does not resort to transformation optics or its quasi-conformal approximations. Our method leads to two-dimensional isotropic, inhomogeneous material profiles of permittivity and permeability, to which a general class of scattering-free wave solutions arise. Our design is based on the separation of the complex wave solution into amplitude and phase. We give two types of examples to validate our methodology.

In this paper, we compare different techniques to manufacture high-performance miniature disks of Terfenol-D aiming at self-powered IoT sensors. To reach large in-plane magnetostriction while maintaining low driving field, microstructure engineering is essential. This work covers monocrystalline, polycrystalline and hot-pressed powder materials whose performances are analyzed. A “performance phase diagram per technique” is reported at the end.

Les nouvelles possibilités d'intégration de capteurs sur des matériels de récolte ouvrent la voie de mesures de qualité intraparcellaires en temps réel. Comment valider les mesures ainsi réalisées ? Pour répondre à cette question, nous avons mis au point un dispositif de prélèvement d'échantillons géoréférencés. L'analyse en laboratoire de ces échantillons permet d'établir des cartes intraparcellaires de référence afin de contrôler les mesures en temps réel. Une première utilisation a concerné la mesure intraparcellaire de la teneur en protéines.

Targeted muscle reinnervation (TMR) is a powerful new tool in preventing and treating residual limb and phantom limb pain. In the adult population, TMR is rapidly becoming standard of care; however, there is a paucity of literature regarding indications and outcomes of TMR in the pediatric population. We present 2 cases of pediatric patients who sustained amputations and the relevant challenges associated with TMR in their cases. One is a 7-year-old patient who developed severe phantom and residual limb pain after a posttraumatic above-knee amputation. He failed pharmacologic measures and underwent TMR. He obtained complete relief of his symptoms and is continuing to do well 1.5 years postoperatively. The other is a 2-year-old boy with bilateral wrist and below-knee amputations as sequelae of sepsis. TMR was not performed because the patient never demonstrated evidence of phantom limb pain or symptomatic neuroma formation. We use these 2 cases to explore the challenges particular to pediatric patients when considering treatment with TMR, including capacity to report pain, risks of anesthesia, and cortical plasticity. These issues will be critical in determining how TMR will be applied to pediatric patients., Competing Interests: FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose., (Copyright © 2022 by the American Academy of Pediatrics.)

Noise exposure can affect sleep, health and cognitive performance, and it disproportionately affects communities of color. This study has the objective of evaluating both conventional and supplemental noise metrics in a community noise survey examining Southwest Detroit, Michigan, a densely populated and industrialized area with extensive truck traffic on residential streets. Sound pressure level (SPL) monitors were deployed at 21 residential sites within 900 m of a major interstate highway. With assistance from youth volunteers, continuous SPL measurements were obtained for 1.5-7 days at each site, and short-term vehicle counts on local roads were recorded. We calculated conventional noise metrics, including the day-evening-night average sound level L DEN and the 90th percentile 1-hr maximum L 10 (h), and evaluated the effect of distance from highways, traffic volume, time-of-day, and other factors. Supplemental metrics potentially appropriate for intermittent traffic noise were calculated, including fraction of time over specific SPL thresholds using a new metric called F DEN , which is the fraction of time over 60, 65 and 70 dB during night, evening and daytime periods, respectively, and a peak noise metric called L 2P (h), which utilizes the 98th percentile SPL within time blocks to increase robustness. The conventional metrics indicated five sites that exceeded 70 dB, and the highest noise levels were found within ~50 m of truck routes, arterials and freeway ramps. The estimated impact of truck traffic ranged up to 17 dB for hourly averages and to 33 dB for 1-s peaks. The conventional metrics did not always capture short-term noise exposures, which may be especially important to annoyance and sleep issues. In addition to showing widespread exposure to traffic noise in the study community that warrants consideration of noise abatement strategies, the study demonstrates the benefits of supplemental noise metrics and community engagement in noise assessment., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Transportation infrastructure decisions contribute to social, economic, and health inequities in the U.S. Health Impact Assessments (HIAs) may improve understanding of potential strategies to mitigate adverse effects on quality of life from planned developments. We use the Gordie Howe International Bridge (GHIB), currently under construction in southwest Detroit, MI, as a case study to examine 15 years of community mobilization, which resulted in community benefits that included an HIA. We describe community engagement processes, household survey methods, and select findings of the baseline HIA, with a focus on their application to inform recommendations to promote quality of life. Baseline HIA results indicated significantly higher self-reported asthma rates among children living within 500 feet of trucking routes. Residents reported substantial economic (e.g., decreased home values), health (e.g., adverse outcomes, lack of health care access), and environmental (e.g., air pollution) concerns related to the GHIB. We discuss specific recommendations, based on HIA results, to reduce adverse impacts of the GHIB. These recommendations will inform ongoing community benefits negotiations. This case study provides lessons for community, academic, and government partners conducting HIAs, especially during building and operation of major infrastructure, and discusses their potential role in improving community engagement opportunities towards environmental justice.

We report the design, fabrication and experimental verification of an illusion device working at microwave frequencies. A two dimensional topology optimization procedure is employed to find the binary layout of a dielectric coating that, when wrapped around a metallic cylinder, mimics the scattering from a predefined, arbitrarily-shaped dielectric object. Fabrication is carried out with 3D-printing and spatially resolved near field measurements in a waveguide configuration were performed, allowing us to map the illusion effect. Our work provides general guidelines for engineering electromagnetic illusions but can be extended to shape the near and far-field radiations using low index isotropic materials.

We present the design of an all-dielectric cloaking device at microwave frequencies. A gradient based topology optimization is employed to find a dielectric permittivity distribution that minimizes the diffracted field in free space. The layout is binary, i.e. made either of standard ABS plastic or air and is designed to reduce the scattering from an ABS cylinder excited by a line source for TE polarization. We study the performances of cloaks optimized for one, two and three frequencies in terms of scattering reduction and correlations with respect to the free space propagation case. Finally, a modal analysis is carried out providing physical insights on the resonant cloaking mechanism at stake.

Subwavelength-sized dielectric Mie resonators have recently emerged as a promising photonic platform, as they combine the advantages of dielectric microstructures and metallic nanoparticles supporting surface plasmon polaritons. Here, we report the capabilities of a dewetting-based process, independent of the sample size, to fabricate Si-based resonators over large scales starting from commercial silicon-on-insulator (SOI) substrates. Spontaneous dewetting is shown to allow the production of monocrystalline Mie-resonators that feature two resonant modes in the visible spectrum, as observed in confocal scattering spectroscopy. Homogeneous scattering responses and improved spatial ordering of the Si-based resonators are observed when dewetting is assisted by electron beam lithography. Finally, exploiting different thermal agglomeration regimes, we highlight the versatility of this technique, which, when assisted by focused ion beam nanopatterning, produces monocrystalline nanocrystals with ad hoc size, position, and organization in complex multimers.

The diffractive behavior of arrays of square coaxial apertures in a gold layer is studied. These structures exhibit a resonant transmission enhancement that is used to design tunable bandpass filters for multispectral imaging in the 7-13 μm wavelength range. A modal analysis is used for this design and the study of their spectral features. Thus we show that the resonance peak is due to the excitation of leaky modes of the open photonic structure. Fourier transform infrared (FTIR) spectrophotometry transmission measurements of samples deposited on Si substrate show good agreement with numerical results and demonstrate angular tolerance of up to 30 degrees of the fabricated filters.

We propose an Adaptive Perfectly Matched Layer (APML) to be used in diffraction grating modeling. With a properly tailored co-ordinate stretching depending both on the incident field and on grating parameters, the APML may efficiently absorb diffracted orders near grazing angles (the so-called Wood's anomalies). The new design is implemented in a finite element method (FEM) scheme and applied on a numerical example of a dielectric slit grating. Its performances are compared with classical PML with constant stretching coefficient.

We study the existence of self-selection and moral hazard in the Chilean health insurance industry. Dependent workers must purchase health insurance either from one public or several private insurance providers. For them, we analyze the relationship between health care services utilization and the choice of either private or public insurance. In the case of independent workers, where there is no mandate, we analyze the relationship between utilization and the decision to voluntarily purchase health insurance. The results show self-selection against insurance companies for independent workers, and against public insurance for dependent workers. Moral hazard is negligible in the case of hospitalization, but for medical visits, it is quantitatively important.

In the course of chronic respiratory insufficiency, acute episodes often require the use of mechanical ventilation. Failure of weaning, or worsening of alveolar hypoventilation, results in long term ventilatory assistance with the need of overall care of the patient. The pneumologist has a key role in the choice of indications, devices and mode of home mechanical ventilation. Thanks to the non-invasive ventilation with a facial or nasal mask, tracheostomy is less often needed. Respiratory failure due to lung restriction is the best indication of mechanical ventilation. The results in COPD are questionable. Whatever to the technique of ventilation and the underlying disease, the pneumologist has to ascertain the steady state of the medical condition, patient and family education, and social situation, all factors to be taken into account before the patient can be discharged. Knowing the specific needs in these patients'care, the pneumologist plays a key role at each stage of home return and follow-up. He co-ordinates the different aspects of pneumological care, like rehabilitation and acute episodes treatment. The overall care of the patients should be improved by the development of health networks in the field of chronic respiratory insufficiency.

Lung transplantation is proposed for young patients with a severe disease that can be expected to be fatal within less than two or three years. The main indications are chronic respiratory failure induced by chronic obstructive lung disease, cystic fibrosis or pulmonary fibrosis, and severe primary or secondary (Eisenmenger syndrome) pulmonary hypertension. The type of transplantation, determined after an exhaustive work-up ruling out all contraindications, is generally a single lung transplantation if there is no bronchial infection or two-lung transplantation or heart-lung transplantation in case of bronchiectasis or pulmonary artery hypertension. Survival at 1, 3 and 5 years is 72, 57 and 43% respectively. Transplantation improves exercise capacity, quality of life and lung function. It normalizes hematosis in case of chronic respiratory failure and pulmonary hemodynamics in case of pulmonary hypertension. The risk of complications, dominated by infections and rejections, requires careful clinical, functional and endoscopic follow-up. Bacterial infections are frequent during the first weeks. The frequency of opportunistic infections can be reduced by anti-infectious prophylaxis strategies. The rejection can occur as an acute episode, frequent during the first 100 days, or is sometimes asymptomatic. Chronic rejection or obliterating bronchiolitis is the main mid-term complication after lung transplantation and is responsible for the low long-term survival rate with recurrent secondary infections due to frequent bronchial colonization with Pseudomonas aeruginosa. Improved prognosis of lung transplantation requires the development of new immunosuppressive agents with lower risk of infection and chronic rejection observed with current treatments.

Ulcerative colitis and sarcoidosis are seldom associated. A 33-year-old diabetic man developed simultaneously a rectitis and a non-productive cough leading to the diagnosis of ulcerative colitis and sarcoidosis. These diagnoses are discussed because of the possible gastrointestinal lesions from sarcoidosis or the respiratory disorders due to ulcerative colitis. Some pathophysiological evidence can be found in this case in favor of a non-fortuitous association.

The hepatopulmonary syndrome (HPS) consists of a triad of liver dysfunction, increased alveolar-arterial oxygen gradient and intrapulmonary vascular dilations. The mechanisms of impaired arterial oxygenation are still debated but the multiple inert gases elimination technique and more recently contrast echocardiography, greatly facilitated the investigation of such mechanisms. Subsequently the cause of hypoxemia can be attributed to several mechanisms such as ventilation-perfusion mismatch, right-to-left intrapulmonary shunts and alveolar-to-capillary diffusion defect, variously implicated in the severity of the disease. SHP may result from intrapulmonary vascular dilations and angiogenesis but the pathogenesis of such abnormalities is not completely explained. The hypothesis of an imbalance in vasoactive mediators and angiogenic factors has been put forward. Increasing data support the theory that the increase in synthesis and release of nitric oxide (NO) is the key factor modulating vascular tone. If this hypothesis is true, the use of compettive inhibitors of NO synthesis should restore pulmonary vascular tone, reversing the hemodynamic changes and gas exchange impairment of HPS.

Section of the anterior cruciate ligament of the right knee was performed in 20 rabbits which were sacrificed 3 months later. During that time, 10 animals were treated with a proteino-polysaccharide compound. The importance of cartilage destruction was evaluated by measuring the articular surfaces and the surface of the fissured areas using an automatic image analyzer; osteophytes were measured by a volumetric study. The percentage of the fissured areas appears to be without correlation with the osteophytosis, the increase of the water content or the decrease of glycosaminoglycans following the procedure. In animals which were treated, the extent of the fissure is significantly reduced but the biochemical and histometric modifications are not too different from those of the reference group.

The average thickness of the last 3 lumbar disks was measured using an automatic image analyzer in 53 patients who were regularly followed-up both clinically and radiographically for an average period of 14.8 years (extremes: 6 and 39 years). This retrospective study showed that disks do not necessarily become pinched with age, even in patients with lumbago, that the rate of disk pinching is extremely variable from one patient to another, that disk collapse takes an average of 20 to 30 years, that there is a correlation between the severity of the lumbago and the rate at which the disk pinches, and that there are rapidly evolutive discopathies which are responsible for severe lumbago.