Integrated fast optical switch fabricated by femtosecond laser micromachining

Integrated optical switches and modulators allow performing reconfigurability in integrated circuits, resulting as fundamental components in different fields ranging from optical communications to sensing and metrology. Among different methods, the thermo-optic effect has been successfully used to fabricate optical modulators by femtosecond laser micromachining (FLM) in glass substrates, proving high stability, no losses dependance but long switching time. In this work, we present an integrated optical switch realized by FLM with a switching time of less than 1 ms: which is about 1 order of magnitude faster than the other devices present in literature. This result has been achieved by carefully optimizing the geometry and the position of resistors and trenches near the waveguides through simulation and experimental validation. In addition, by means of an optimization of the applied voltage signal, we have demonstrated a further significant temporal improvement, measuring a switching time of less than 100 μs

Integrated optical device for Structured Illumination Microscopy

Structured Illumination Microscopy (SIM) is a key technology for high resolution and super-resolution imaging of biological cells and molecules. The spread of portable and easy-to-align SIM systems requires the development of novel methods to generate a light pattern and to shift it across the field of view of the microscope. Here we show a miniaturized chip that incorporates optical waveguides, splitters, and phase shifters, to generate a 2D structured illumination pattern suitable for SIM microscopy. The chip creates three point-sources, coherent and controlled in phase, without the need for further alignment. Placed in the pupil of a microscope's objective, the three sources generate a hexagonal illumination pattern on the sample, which is spatially translated thanks to thermal phase shifters. We validate and use the chip, upgrading a commercial inverted fluorescence microscope to a SIM setup and we image biological sample slides, extending the resolution of the microscope. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreemen

Strategies for improved temporal response of glass-based optical switches

We present an optimization of the dynamics of integrated optical switches based on thermal phase shifters. These devices have been fabricated in the volume of glass substrates by femtosecond laser micromachining and are constituted by an integrated Mach–Zehnder interferometer and a superficial heater. Simulations, surface micromachining and innovative layouts allowed us to improve the temporal response of the optical switches down to a few milliseconds. In addition, taking advantage of an electrical pulse shaping approach where an optimized voltage signal is applied to the heater, we proved a switching time as low as 78 µs, about two orders of magnitude shorter with respect to the current state of the art of thermally-actuated optical switches in glass

The process of care in residential facilities. A national survey in Italy

Background: Although residential facilities (RFs) have largely replaced mental hospitals (MHs) in most developed countries for the long-term residential care of severely impaired patients, the process of care in RFs has not been well studied. The aim of this paper is to investigate the process of care in 265 RFs, representing 19.3% of all RFs in Italy, and to devise a classification of RFs based on process characteristics. Methods: Structured interviews were conducted with the manager and staff of each RF. Residents were evaluated using standardized rating instruments. Results: Most RFs had specific admission criteria, with one third having a waiting list that averaged about 3 months. There was no formal limitation to the length of stay in three quarters of RFs, and turnover rates were very low. Although a homelike atmosphere was found in many RFs, most facilities had restrictive rules on patients' daily lives and behaviours. RFs carried out several external activities targeted at integrating patients within the local community. Standardized assessment instruments and written treatment plans were rarely used. A cluster analysis based on the levels of restrictiveness and the standardization of the process of care classified RFs into five groups that differed with respect to daily staff coverage, size, geographical distribution and proportion of former MH residents. No significant intercluster differences were associated with the current clinical and psychosocial characteristics of residents, or with several other outcome variables. Conclusions: This study provides naturalistic evidence of the heterogeneity of the process of residential care on a large scale. Future efforts should focus on developing an empirical classification of RFs, as well as on national and international standards of care and staffing to address patients' needs

The Italian PROGRES project on non-hospital residential facilities [Le strutture residenziali psichiatriche in Italia. I risultati della fase 1 del progetto PROGRES]

Objective - The 'PROGRES' (PROGetto RESidenze' Residential Project) project has 3 aims: 1. To survey all Italian psychiatric Non-Hospital Residential Facilities (NHRF) (Phase 1); 2. To assess in detail 20% of the NHRFs and the patients living there (Phase 2); and 3. To carry on training programmes for the mental health workers of these facilities (Phase 3). We report here the results of Phase 1. Methods - All NHRFs were surveyed using a structured interview administered to the manager of the facility. In some cases, this information was supplemented with data gathered from other mental health workers at the NHRFs. Results - On May 31, 2000, there were in Italy 1,370 NHRFs with 17,138 beds, giving an average number of beds per facility of 12.5 and a rate of 2.98 beds per 10,000 inhabitants. This rate varies greatly between regions, with a ratio of 1:10 between the two regions with the lowest and the highest bed rates. Seventy-three percent of the NHRFs have a 24-hour staff coverage; more than 50% are directly managed by the NHS Departments of Mental Health and more than three-quarters of the NHRFs are directly funded by the NHS. In the course of 1999 38% of the NHRFs discharged no patients, and another 32% discharged fewer than 3 patients. In about half of the NHRFs the most common patient age group was 40-59 years. In the Italian NHRFs there are 11,240 full-time mental health workers, plus several thousand half-time staff. The average number of full-time mental health workers in each NHRF is 8.2. In 58% of the NHRFs the operational chief is a psychiatrist; some 40% of the overall number of mental health workers in the NHRFs have no specific psychiatric training. The total number of patients resident in the NHRFs is 15,943; among them, 58% have never been admitted to a mental hospital, 40% have been admitted and a small percentage (1.6%) has been previously admitted to a forensic mental hospital. The availability of NHRF beds is negatively associated with the availability of non-hospital facilities (e.g., community mental health centres, day-centres) and positively associated with the number of beds in private psychiatric facilities in each region. Discussion - The current rate of NHRF beds is higher than the officially recommended national standard (2/10,000 inhabitants). However, there is a great variability between regions, which is related to the overall provision of different types of psychiatric facilities. Most NHRFs provide intensive care, and the continuum of residential facilities with different types of care, support, degree of autonomy, etc. recommended by several authors for the long-term treatment of severe patients with different disabilities, seem to be lacking. NHRFs have a very low patient turnover rate, and this may create problems in the future. Conclusions - The PROGRES project is the first national study ever carried out in Italy to evaluate a specific type of psychiatric facilities in the context of the new system of psychiatric care. When all the data will be available, it will be possible to assess in detail for the first time a national representative sample of severe, long-stay patients and the care they are receiving; on this basis, it will also be possible to recommend evidence-based policies aimed at improving the care of the severely mentally ill