A hybrid achromatic metalens Balli, F.; Sultan, M.; Lami, Sarah K. ...
Nature communications,
08/2020, Letnik:
11, Številka:
1
Journal Article
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Abstract
Metalenses, ultra-thin optical elements that focus light using subwavelength structures, have been the subject of a number of recent investigations. Compared to their refractive ...counterparts, metalenses offer reduced size and weight, and new functionality such as polarization control. However, metalenses that correct chromatic aberration also suffer from markedly reduced focusing efficiency. Here we introduce a Hybrid Achromatic Metalens (HAML) that overcomes this trade-off and offers improved focusing efficiency over a broad wavelength range from 1000–1800 nm. HAMLs can be designed by combining recursive ray-tracing and simulated phase libraries rather than computationally intensive global search algorithms. Moreover, HAMLs can be fabricated in low-refractive index materials using multi-photon lithography for customization or using molding for mass production. HAMLs demonstrated diffraction limited performance for numerical apertures of 0.27, 0.11, and 0.06, with average focusing efficiencies greater than 60% and maximum efficiencies up to 80%. A more complex design, the air-spaced HAML, introduces a gap between elements to enable even larger diameters and numerical apertures.
The steadily increasing luminosity of the LHC requires an upgrade with high-rate and high-resolution detector technology for the inner end cap of the ATLAS muon spectrometer: the New Small Wheels ...(NSW). In order to achieve the goal of precision tracking at a hit rate of about 15 kHz/cm2 at the inner radius of the NSW, large area Micromegas quadruplets with 100µm spatial resolution per plane have been produced. IRFU, from the CEA research center of Saclay, is responsible for the production and validation of LM1 Micromegas modules. The construction, production, qualification and validation of the largest Micromegas detectors ever built are reported here. Performance results under cosmic muon characterization will also be discussed.
This work reports on design and performance of a depleted monolithic active pixel sensor (DMAPS) prototype manufactured in the LFoundry 150 nm CMOS process. DMAPS exploit high voltage and/or high ...resistivity inclusion of modern CMOS technologies to achieve substantial depletion in the sensing volume. The device used in this work, named LF-Monopix, was designed as a proof of concept of a fully monolithic sensor capable of operating in the environment of outer layers of the ATLAS Inner Tracker upgrade in 2025 for the High Luminosity Large Hadron Collider (HL-LHC). This type of devices has a lower production cost and lower material budget compared to presently used hybrid designs. In this work, the chip architecture will be described followed by the characterization of the different pixel flavors with an external injection signal and an iron source (5.9keV x-rays).
Summary
Backgroud Coeliac disease (CD) can be associated with liver disease. Gluten‐free diet (GFD) normalizes cryptogenic forms, but most likely not autoimmune hepatitis (AIH). For this condition, ...immunosuppressants represent the treatment. However, when these are stopped, AIH generally relapses.
Aim To determine in CD children liver test abnormality frequency, the effect of GFD alone, or plus prolonged immunosuppressants on AIH course.
Methods Coeliac disease patients with abnormal transaminases were selected; if transaminases <5 × UNL (upper normal limits), GFD alone was administered; if >5 × UNL, liver examinations and biopsy were performed. In AIH, immunosuppressants were administered (5 years). Treatment was stopped only if patients remained in remission during the entire maintenance period and normalized liver histology.
Results A total of 140 out of 350 CD children had hypertransaminaemia: 133 cryptogenic disease, 7 AIH. GFD normalized only cryptogenic hepatitis. During treatment, all AIH persistently normalized clinical and biochemical parameters; after withdrawal, six patients maintained a sustained remission (follow‐up range: 12–63 months), while one relapsed.
Conclusions In CD children with AIH, only GFD plus immunosuppressants determines a high remission rate. When clinical remission is reached, a prolonged immunosuppressive regimen induces a high sustained remission rate after treatment withdrawal, indicating that this regimen may prevent early relapse.
Aliment Pharmacol Ther 31, 253–260
We investigate income smoothing associated with international portfolio diversification by decomposing the net factor income (NFI) channel into interests, dividends and retained earnings, for OECD ...and EU countries. We find that interest receipts and equity dividend payments contribute significantly to absorb domestic income shocks. Geographically concentrated portfolios and, in particular, biases toward EU markets have a strong negative effect on the degree of risk-sharing.
•This paper analyzes risk sharing from internationally diversified portfolios.•The factor income channel is decomposed into interest, dividend and retained earning.•Interest receipts, dividend payments significantly contribute to absorb output shocks.•Biases to EU markets negatively affect the extent of risk sharing.
Background: The purpose was to assess in Italy the clinical features at diagnosis of inflammatory bowel disease (IBD) in children.
Methods: In 1996 an IBD register of disease onset was established on ...a national scale.
Results: Up to the end of 2003, 1576 cases of pediatric IBD were recorded: 810 (52%) ulcerative colitis (UC), 635 (40%) Crohn's disease (CD), and 131 (8%) indeterminate colitis (IC). In the period 1996–2003 an increase of IBD incidence from 0.89 to 1.39/105 inhabitants aged <18 years was observed. IBD was more frequent among children aged between 6 and 12 years (57%) but 20% of patients had onset of the disease under 6 years of age; 28 patients were <1 year of age. Overall, 11% had 1 or more family members with IBD. The mean interval between onset of symptoms and diagnosis was higher in CD (10.1 months) and IC (9 months) versus UC (5.8 months). Extended colitis was the most frequent form in UC and ileocolic involvement the most frequent in CD. Upper intestinal tract involvement was present in 11% of CD patients. IC locations were similar to those of UC. Bloody diarrhea and abdominal pain were the most frequent symptoms in UC and IC, and abdominal pain and diarrhea in CD. Extraintestinal symptoms were more frequent in CD than in UC.
Conclusions The IBD incidence in children and adolescents in Italy shows an increasing trend for all 3 pathologies. UC diagnoses exceeded CD.
(Inflamm Bowel Dis 2008)
Background Adherence to respiratory physiotherapy is a major challenge in children with cystic fibrosis (CF). Video games have shown promising results in improving adherence to treatment in chronic ...diseases. However, the feasibility of adapting video games to positive expiratory pressure (PEP) therapy in CF has not been explored. Hypothesis Therapeutic games can be adapted to PEP therapy. Methods In collaboration with students in the game design program of University of Montreal, we developed and adapted 3 video games to the parameters of PEP therapy (6 series of 15 respirations). The PARI's PEP S™ device was connected to a computer by a pressure sensor. Ten children (5 girls, 5 boys) between the age of 8 and 10 tested the video games on one occasion during PEP therapy under the supervision of the physical therapist of the CHU Sainte-Justine CF clinic. Questionnaires were completed before and after the trial by all participants which consisted of their overall evaluation of the games, their interest in pursuing the video games at home and whether they believe the games may improve adherence to PEP therapy. Results The PARI's PEP S™ device was successfully connected to a computer and all PEP parameters were monitored adequately. Nine children (9/10) were very interested in pursuing the video games while doing their PEP therapy at home. All of them thought that the games were well adapted to the PEP therapy and that it may improve their adherence to the treatment. Conclusion Video games can be adapted to PEP therapy. A second study is currently being planned to investigate whether video games may improve adherence to respiratory physiotherapy in children with CF.
The worldwide increase of celiac disease prompted us to assess its prevalence in the Italian general population. The 3483 inhabitants of Campogalliano were tested for immunoglobulin A anti-endomysial ...antibodies. Twenty subjects showed antibody positivity and duodenal biopsy detected typical mucosal lesions of celiac disease in 17 of them; the remaining three cases had a normal villous architecture, but the finding of increased gamma/delta intraepithelial lymphocytes in all and the heterodimer DQA1*0501, DQB1*0201 in two of them was consistent with potential celiac disease. Only one patient had an overt malabsorption syndrome, characterized by diarrhea, weight loss, and severe weakness. In eight subjects atypical symptoms of celiac disease, such as dyspepsia and depression, were present, whereas the remaining subjects were silent. Celiac disease was more frequent in younger age groups. Our cross-sectional design study demonstrates that celiac disease prevalence in the Italian general population is 4.9 per 1000 (95% CI 2.8-7.8), increasing up to 5.7 per 1000 (95% CI 3.5-8.8) with the inclusion of potential cases.
We investigate pair-wise, net and total return and volatility spillovers across 15 Islamic equity markets from widely dispersed locations. Using the generalized VAR-based spillovers index between ...2007 and 2017, we find increasing interactions in return and volatility spillovers while the extent of spillovers has been asymmetric across the countries. Interestingly, we find the presence of persistent clustering of spillovers (viz., Qatar - UAE - Saudi Arabia and Turkey - Malaysia - Indonesia). These clustered countries lead Islamic equity return and volatility spillovers in their respective regions. We do not find any supremacy of the cash and oil-rich GCC countries outside their region. Our results also highlight that in crises periods, aggregate spillovers across the Islamic equity markets intensify. Additionally, we employ cross-section analyses to investigate the underlying macroeconomic variables influencing the magnitude of such spillovers. We find convincing evidence of geographic proximity along with economic and financial linkages that explain the directions of return and volatility spillovers.
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