6-channel CMOS-based instrument for optical absorption spectroscopy and chemical identification

A multichannel portable instrument for on-chip optical absorption spectroscopy is presented. The system can house photonic chips having up to 6 sensing sites operating in parallel, allowing real-time simultaneous detection of multiple chemicals. A 6-channel CMOS lock-in front-end performs the amplification and demodulation of the signals from the integrated light detectors, while an FPGA is chosen for signal acquisition and analysis. A digital real-time ratiometric processing cancels out the effect of laser power fluctuations to achieve high sensitivity in monitoring the presence of the analytes, as demonstrated with the detection of an acetone sample. Compact size for portability, real-time parallel detection and flexible FPGA processing make this system suitable for environmental investigations on many different pollutants, both in the near- and mid-infrared wavelength range

Maternal HIV status and infant feeding practices among Ugandan women

To describe the infant feeding practices in the general population in Uganda, and to assess the impact of maternal HIV status on these practices, a questionnaire was administered to women attending the follow-up clinics for child vaccination. Among the mothers who were still breastfeeding at the time of interview (N=838), 61.4% of the HIV-infected women had planned to breastfeed for a maximum of 6 months, compared with 12.1% of the HIV-uninfected women (

Establishing Multiple Chip-to-Chip Orthogonal Free-Space Optical Channels using Programmable Silicon Photonics Meshes

Two silicon photonics programmable meshes of Mach-Zehnder interferometers are used to automatically establish chip-to-chip orthogonal free-space communication links. Optimum channels with mutual isolation of more than 30dB are found even in case of a misaligned link or in presence of an obstacle in the path

Self-Configuring Silicon-Photonic Receiver for Multimode Free Space Channels

A self-configuring mesh of silicon Mach-Zehnder Interferometers is employed to receive two spatially overlapped orthogonal beams modulated at 10 Gbit/s. These beams, sharing the same wavelength and state of polarization, are separated with more than 30 dB isolation, and sorted out with no signal degradation

Multimode Free Space Optical Link Enabled by SiP Integrated Meshes

A silicon photonic mesh of tuneable Mach-Zehnder Interferometers (MZIs) is employed to receive two spatially-overlapped Hermite-Gaussian beams modulated at 10 Gbit/s, sharing the same wavelength and state of polarization. The mesh automatically self-configures, separating and sorting the two beams out without any excess loss

Separating arbitrary free-space beams with an integrated photonic processor

Free-space optics naturally offers multiple-channel communications and sensing exploitable in many applications. The different optical beams will, however, generally be overlapping at the receiver, and, especially with atmospheric turbulence or other scattering or aberrations, the arriving beam shapes may not even be known in advance. We show that such beams can be still separated in the optical domain, and simultaneously detected with negligible cross-talk, even if they share the same wavelength and polarization, and even with unknown arriving beam shapes. The kernel of the adaptive multibeam receiver presented in this work is a programmable integrated photonic processor that is coupled to free-space beams through a two-dimensional array of optical antennas. We demonstrate separation of beam pairs arriving from different directions, with overlapping spatial modes in the same direction, and even with mixing between the beams deliberately added in the path. With the circuit’s optical bandwidth of more than 40 nm, this approach offers an enabling technology for the evolution of FSO from single-beam to multibeam space-division multiplexed systems in a perturbed environment, which has been a game-changing transition in fiber-optic systems

Temperature and wavelength drift tolerant WDM transmission and routing in on-chip silicon photonic interconnects

We demonstrate a temperature and wavelength shift resilient silicon transmission and routing interconnect system suitable for multi-socket interconnects, utilizing a dual-strategy CLIPP feedback circuitry that safeguards the operating point of the constituent photonic building blocks along the entire on-chip transmission-multiplexing-routing chain. The control circuit leverages a novel control power-independent and calibration-free locking strategy that exploits the 2nd derivative of ring resonator modulators (RMs) transfer function to lock them close to the point of minimum transmission penalty. The system performance was evaluated on an integrated Silicon Photonics 2-socket demonstrator, enforcing control over a chain of RM-MUX-AWGR resonant structures and stressed against thermal and wavelength shift perturbations. The thermal and wavelength stress tests ranged from 27 degrees C to 36 degrees C and 1309.90 nm to 1310.85 nm and revealed average eye diagrams Q-factor values of 5.8 and 5.9 respectively, validating the system robustness to unstable environments and fabrication variations. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreemen

Point of view of the Italians pediatric scientific societies about the pediatric care during the COVID-19 lockdown: What has changed and future prospects for restarting

Background: The coronavirus disease 2019 (COVID-19) is currently rare in children and they seem to have a milder disease course and better prognosis than adults. However, SARS-Cov-2 pandemic has indirectly caused problems in pediatric medical assistance. In view of this we wanted to draw a picture of what happened during health emergency and analyze future prospects for restarting. Methods: We involved the Italian pediatric scientific societies institutionally collected in the Italian Federation of Associations and Scientific Societies of the Pediatric Area (FIARPED); We sent a questionnaire to all scientific societies about the pediatric care activity during the COVID-19 emergency and future perspectives for the phase of post-containment. Results: The analysis of the questionnaires showed significant decrease of:admission, outpatient visits and specialist consultancy activities during the COVID-19 emergency, primarily linked to the fear of infection. Instead it was increased the serious degree of diseases admitted. Most of scientific societies maintained the relationship with chronic patients through some form of telemedicine, reporting a strong positive opinion about this modality. Finally showed the need to give life a new approach for hospitalizations and outpatient visits through a greater use of telemedicine, educational programs on families and a more decisive role of family pediatricians. Conclusions: Our study highlighted many aspects that can be improved in pediatric care. We think that It will be necessary a new shared strategy to improve the management and continuity of care for pediatric patients, primarily developing a network of collaboration between families, family pediatrician and hospitals and by enhancing the use of new methods of telecommunications