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1.
Clin Pract ; 11(4): 860-869, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34842630

RESUMO

OBJECTIVE: The aim was to estimate the perceived quality of life and its relationship with sociodemographic and professional factors, perception of susceptibility to COVID-19, and stress. DESIGN: It was a longitudinal study. SUBJECTS: Professionals, working in Italian centers for pediatric neurocognitive, speech, and psychomotor rehabilitation. METHODS: Participants were interviewed online twice during the COVID-19 outbreak in Italy. The questionnaire included: (i) The measures of health-related quality of life to perform the Summary Index of Unhealthy Days, (ii) modified items from the "Standard questionnaire on risk perception of an infectious disease outbreak" and (iii) the items of the General Health Questionnaire. RESULTS: One hundred and thirty professionals out of 130 participated in the first interview, while only 50 therapists took part in the second interview (dropout rate: 61%). The Summary Index of Unhealthy Days was 8 days at the first interview, and it decreased to 6 days at the second interview; however, the reduction was not significant (F = 3.22; p = 0.079). The multivariable analysis showed that the rehabilitation providers with moderate or severe stress level were more likely to have a negative perception of the quality of life (ORadj = 7.155; 95% CI: 2.8-18.2), and this result was confirmed at the second interview. CONCLUSIONS: Our results showed that in a severe public health emergency, the mental health and quality of life of rehabilitation professionals must be a topic of focus to enhance psychological resilience, to prevent burnout and to reduce rehabilitation errors.

2.
Opt Express ; 29(21): 33380-33397, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809151

RESUMO

Mesoscopic Photonic Crystals (MPhCs) are composed of alternating natural or artificial materials with compensating spatial dispersion. In their simplest form, as presented here, MPhCs are composed by the periodic repetition of a MPhC supercell made of a short slab of bulk material and a short slab of Photonic Crystal (PhCs). Therefore, MPhCs present a multiscale periodicity with a subwavelength periodicity within each PhC slab and with a few-wavelength periodicity for its supercell. Thanks to this mesoscopic structure, MPhCs allow the self-collimation of light, through a mechanism called mesoscopic self-collimation (MSC), along both directions of high symmetry and directions oblique with respect to the MPhCs slab interfaces. Here, we propose a new design method useful for conceiving MPhCs that allow MSC under oblique incidence, avoiding in-plane scattering and ensuring propagation via purely guided modes, without out-of-plane radiation losses. In addition, the proposed method allows a systematic search for optimal MSC structures, which also simultaneously satisfy the impedance matching condition at MPhC interfaces, thus reducing the effect of multiple reflections between bulk-PhC interfaces. The proposed design method has the advantage of an extreme analytical simplicity and it allows direct design of oblique-incidence MPhC structures. Its accuracy is validated through Finite Difference Time Domain simulations and the MSC performances of the designed structures are evaluated, in terms of angular direction, beam waist, overall transmittance, and through discussion of a Figure of Merit that accounts for residual beam curvature. This simple yet powerful method can pave the way for the design of advanced MSC-based photonic interconnects and circuits that are immune to crosstalk and out-of-plane losses.

3.
Opt Express ; 29(20): 31212-31228, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615219

RESUMO

In this paper we report the design of a device allowing on-chip optical wireless interconnections, based on transmitting and receiving Optical Phased Arrays (OPA). The proposed device aims at realizing high-bandwidth and power-efficient reconfigurable connections between multiple nodes, e.g. chiplets stacked onto a common silicon interposer in 2.5D manycore systems. The communication through an optical wireless switch is a completely novel approach to overcome the bottleneck of wired communication and to provide flexibility in the network topology configuration. We report the OPA design criteria as well as the results of three-dimensional Finite Difference Time Domain (FDTD) simulations. We exploit the in-plane radiation of simple taper antennas to implement 1×N and N × N switching matrices. The effect of the multipath propagation in the on-chip multi-layered medium is also taken into account.

4.
Opt Express ; 27(21): 30287-30296, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684278

RESUMO

Self-collimation (SC) and mesoscopic self-collimation (MSC) have been successfully demonstrated along the directions of high symmetry of photonic crystals. Indeed, wide angular acceptances are obtained only in these directions which offer extremely flat isofrequencies. In this article, we numerically demonstrate that mesoscopic self-collimation with large angular acceptance can be achieved along arbitrary directions that are not of high symmetry. In particular, we propose a simple method that allows to easily find all the non-trivial collimation directions and corresponding frequencies. Thanks to the double periodicity of the mesoscopic crystal, these solutions can be effectively tailored in terms of direction and frequency. Moreover, non-trivial MSC solutions can be found well below the light cone. These MSC features open up the possibility of designing complex systems by combining different configurations, such as high reflection (HR) or anti reflection (AR) ones, or active materials.

5.
Am J Perinatol ; 36(S 02): S115-S119, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31238371

RESUMO

BACKGROUND: The application of noninvasive ventilation (NIV) modalities from birth in the delivery room (DR) during fetal-neonatal transition reduces the need for invasive mechanical ventilation, mortality, and bronchopulmonary dysplasia (BPD). The use of a RAM nasal cannula (RAM NC) in the DR for resuscitation results in less need for intubation, chest compressions, and epinephrine administration when compared with using a face mask for PPV in the DR. OBJECTIVE: To evaluate the need for endotracheal intubation in the DR among extremely low gestational age neonates treated at birth with sustained inflation (SI) followed by a nasal continuous positive airway pressure (NCPAP) (range: 6-8 cm of H2O) delivered through the RAM NC. STUDY DESIGN: A retrospective study was conducted to compare the use of NIV techniques in the DR and the need for intubation in the DR in premature infants 23 to 28 weeks' gestational age from December 2016 to July 2018 (group A). These data were compared with those of premature inborn infants with similar GA born between April 2015 and November 2016 (group B). In the DR, immediately after birth, neonates in group A received SI through RAM NC followed by CPAP ranging from 6 to 8 cm H2O, whereas the neonates in group B were treated in the DR with SI administered through a face mask followed by the application of CPAP of 5 cm H2O delivered through a nasopharyngeal tube. RESULTS: A total of 65 preterm infants 23 to 28 weeks of gestational age, 31 in group A and 34 in group B, were included in the study. The percentage of neonates intubated in the DR was significantly lower in group A (p < 0.008). In both groups, no neonates died in the DR, and no one required epinephrine and/or chest compressions. For those neonates who did not require intubation in the DR, there was no significant difference in the average FiO2 on arrival in the neonatal intensive care unit, rate of intubation within 24 hours, and use of surfactant. The incidence of BPD was similar in the two groups. Only one infant in group A developed moderate BPD, and no one needed oxygen and/or ventilatory assistance at discharge. Mortality was similar in the two groups, with a slight prevalence in group B (27.7 vs. 19.2%). CONCLUSION: SI with RAM NC followed by NCPAP ranging from 6 to 8 cm H2O, administered with RAM NC resulted in a significant reduction of intubation in the DR.


Assuntos
Cânula , Pressão Positiva Contínua nas Vias Aéreas , Lactente Extremamente Prematuro , Ventilação não Invasiva/métodos , Ressuscitação/métodos , Salas de Parto , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro , Intubação Intratraqueal , Masculino , Máscaras , Estudos Retrospectivos
6.
Opt Express ; 26(23): 30267-30277, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30469902

RESUMO

Optical technology applied to on-chip wireless communication is particularly promising to overcome the performance limitations of the state-of-the-art networks on-chip. A key enabling component for such applications is the plasmonic antenna coupled to conventional silicon waveguides, which can guarantee full compatibility with standard optical circuitry. In this paper, we propose an antenna array configuration based on tilted plasmonic Vivaldi antennas coupled to a silicon waveguide. The details of the single antenna and of the array design are reported. The radiation characteristics of the array are suitable for on-chip point-to-point communication, i.e. in-plane maximum gain of 14.70 dB for an array with five antennas. The array exploits a travelling wave feeding scheme and, therefore, is compact in size (about 3.5 µm × 8.7 µm ).

7.
Opt Express ; 25(14): 16214-16227, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28789129

RESUMO

In this paper we propose a novel hybrid optical plasmonic Vivaldi antenna for operation in the standard C telecommunication band for wavelengths in the 1550 nm range. The antenna is fed by a silicon waveguide and is designed to have high gain and large bandwidth. The shape of the radiation pattern, with a main lobe along the antenna axis, makes this antenna suitable for point-to-point connections for inter- or intra-chip optical communications. Direct port-to-port short links for different connection distances and in a homogeneous environment have also been simulated to verify, by comparing the results of a full-wave simulation with the Friis transmission equation, the correctness of the antenna parameters obtained via near-to-far field transformation.

8.
Artigo em Inglês | MEDLINE | ID: mdl-21384710

RESUMO

In this paper the design of a handheld light applicator for microwave heating is presented. The applicator is made of an array of resonant longitudinal slots cut on a broad wall of a rectangular waveguide, and it is covered by a cylindrical lens made of Plexiglas with a permittivity of 2.53. The geometrical optics approach is used as initial approximation to establish the lens profile. It allows for the shaping of the slotted waveguide's radiation pattern into a desired output pattern in the transversal plane. Three-dimensional simulation results show that the applicator performance can be improved at 2.45 GHz by using a homogeneous dielectric lens.

9.
Artigo em Inglês | MEDLINE | ID: mdl-19227070

RESUMO

The electromagnetic and thermal analyses of a mode-stirred chamber designed for the heat treatment of antique and precious books are proposed. In particular, the electromagnetic and thermal perturbations due to the presence of metallic insets inside the treated material (paper) are investigated. The temperature measurement results obtained by thermography and by temperature fiber-optic sensor are also reported. Finally, metallic shields are experimentally demonstrated to prevent the overheating of the treated material and the consequent damage of the antique tomes.

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