Structured illumination generation with an integrated optical chip

Structured illumination is a widely used technique in fluorescence microscopy that allows for super-resolution imaging. In this paper, a brief introduction to the topic will be presented, together with a compact and integrated optical device that can generate and spatially translate a structured light pattern suitable for SIM microscopy. The device uses optical waveguides and directional couplers made with femtosecond laser micromachining. The beams are directed through an optical coupler to create the illumination pattern after interfering. The phase of the beams in the waveguides can be adjusted using thermal phase-shifters so that it is possible to shift the illumination pattern over the field of view of the microscope, enabling the acquisition of multiple phase images for SIM reconstruction without the need for additional optical elements. The effectiveness of the device is demonstrated by showing its use in a commercially available inverted microscope for superresolution imaging of Bovine Pulmonary Artery Endothelial Cells (BPAE Line) deposited on a commercial glass slide

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

On the role of energy infrastructure in the energy transition. Case study of an energy independent and CO2 neutral energy system for Switzerland

The transition towards renewable energy is leading to an important strain on the energy grids. The question of designing and deploying renewable energy technologies in symbiosis with existing grids and infrastructure is arising. While current energy system models mainly focus on the energy transformation system or only investigate the effect on one energy vector grid, we present a methodology to characterize different energy vector grids and storage, integrated into the multi-energy and multi-sector modeling framework EnergyScope. The characterization of energy grids is achieved through a traditional energy technology and grid modeling approach, integrating economic and technical parameters. The methodology has been applied to the case study of a country with a high existing transmission infrastructure density, e.g., Switzerland, switching from a fossil fuel-based system to a high share of renewable energy deployment. The results show that the economic optimum with high shares of renewable energy requires the electric distribution grid reinforcement with 2.439 GW (+61%) Low Voltage (LV) and 4.626 GW (+82%) Medium Voltage (MV), with no reinforcement required at transmission level [High Voltage (HV) and Extra High Voltage (EHV)]. The reinforcement is due to high shares of LV-Photovoltaic (PV) (15.4 GW) and MV-wind (20 GW) deployment. Without reinforcement, additional biomass is required for methane production, which is stored in 4.8–5.95 TWh methane storage tanks to compensate for seasonal intermittency using the existing gas infrastructure. In contrast, hydro storage capacity is used at a maximum of 8.9 TWh. Furthermore, the choice of less efficient technologies to avoid reinforcement results in a 8.5%–9.3% cost penalty compared to the cost of the reinforced system. This study considers a geographically averaged and aggregated model, assuming all production and consumption are made in one single spot, not considering the role of future decentralization of the energy system, leading to a possible overestimation of grid reinforcement needs

Structured-light-sheet imaging in an integrated optofluidic platform

: Heterogeneity investigation at the single-cell level reveals morphological and phenotypic characteristics in cell populations. In clinical research, heterogeneity has important implications in the correct detection and interpretation of prognostic markers and in the analysis of patient-derived material. Among single-cell analysis, imaging flow cytometry allows combining information retrieved by single cell images with the throughput of fluidic platforms. Nevertheless, these techniques might fail in a comprehensive heterogeneity evaluation because of limited image resolution and bidimensional analysis. Light sheet fluorescence microscopy opened new ways to study in 3D the complexity of cellular functionality in samples ranging from single-cells to micro-tissues, with remarkably fast acquisition and low photo-toxicity. In addition, structured illumination microscopy has been applied to single-cell studies enhancing the resolution of imaging beyond the conventional diffraction limit. The combination of these techniques in a microfluidic environment, which permits automatic sample delivery and translation, would allow exhaustive investigation of cellular heterogeneity with high throughput image acquisition at high resolution. Here we propose an integrated optofluidic platform capable of performing structured light sheet imaging flow cytometry (SLS-IFC). The system encompasses a multicolor directional coupler equipped with a thermo-optic phase shifter, cylindrical lenses and a microfluidic network to generate and shift a patterned light sheet within a microchannel. The absence of moving parts allows a stable alignment and an automated fluorescence signal acquisition during the sample flow. The platform enables 3D imaging of an entire cell in about 1 s with a resolution enhancement capable of revealing sub-cellular features and sub-diffraction limit details

Diurnal changes in middle atmospheric H2O and O3: Observations in the Alpine region and climate models

International audienceIn this paper we investigate daily variations in middle atmospheric water vapor and ozone based on data from two ground-based microwave radiometers located in the Alpine region of Europe. Temperature data are obtained from a lidar located near the two stations and from the SABER experiment on the TIMED satellite. This unique set of observations is complemented by three different three-dimensional (3-D) chemistry-climate models (Monitoring of Stratospheric Depletion of the Ozone Layer (MSDOL), Laboratoire de Météorologie Dynamique Reactive Processes Ruling the Ozone Budget in the Stratosphere (LMDz-REPROBUS), and Solar Climate Ozone Links (SOCOL)) and the 2-D atmospheric global-scale wave model (GSWM). The first part of the paper is focused on the first Climate and Weather of the Sun-Earth System (CAWSES) tidal campaign that consisted of a period of intensive measurements during September 2005. Variations in stratospheric water vapor are found to be in the order of 1% depending on altitude. Meridional advection of tidal nature is likely to be the dominant driving factor throughout the whole stratosphere, while vertical advection becomes more important in the mesosphere. Observed ozone variations in the upper stratosphere and lower mesosphere show amplitudes of several percent in accordance with photochemical models. Variations in lower stratospheric ozone are not solely governed by photochemistry but also by dynamics, with the temperature dependence of the photochemistry becoming more important. The second part presents an investigation of the seasonal dependence of daily variations. Models tend to underestimate the H2O diurnal amplitudes, especially during summer in the upper stratosphere. Good agreement between models and observations is found for ozone in the upper stratosphere, which reflects the fact that the O3 daily variations are driven by the photochemistry that is well modeled

Long-term evolution of upper stratospheric ozone at selected stations of the Network for the Detection of Stratospheric Change (NDSC)

The long-term evolution of upper stratospheric ozone has been recorded by lidars and microwave radiometers within the ground-based Network for the Detection of Stratospheric Change (NDSC), and by the space-borne Solar Backscatter Ultra-Violet instruments (SBUV), Stratospheric Aerosol and Gas Experiment (SAGE), and Halogen Occultation Experiment (HALOE). Climatological mean differences between these instruments are typically smaller than 5% between 25 and 50 km. Ozone anomaly time series from all instruments, averaged from 35 to 45 km altitude, track each other very well and typically agree within 3 to 5%. SBUV seems to have a slight positive drift against the other instruments. The corresponding 1979 to 1999 period from a transient simulation by the fully coupled MAECHAM4-CHEM chemistry climate model reproduces many features of the observed anomalies. However, in the upper stratosphere the model shows too low ozone values and too negative ozone trends, probably due to an underestimation of methane and a consequent overestimation of ClO. The combination of all observational data sets provides a very consistent picture, with a long-term stability of 2% or better. Upper stratospheric ozone shows three main features: (1) a decline by 10 to 15% since 1980, due to chemical destruction by chlorine; (2) two to three year fluctuations by 5 to 10%, due to the Quasi-Biennial Oscillation (QBO); (3) an 11-year oscillation by about 5%, due to the 11-year solar cycle. The 1979 to 1997 ozone trends are larger at the southern mid-latitude station Lauder (45 S), reaching 8%/decade, compared to only about 6%/decade at Table Mountain (35 N), Haute Provence/Bordeaux ( 45 N), and Hohenpeissenberg/Bern( 47 N). At Lauder, Hawaii (20 N), Table Mountain, and Haute Provence, ozone residuals after subtraction of QBO- and solar cycle effects have levelled off in recent years, or are even increasing. Assuming a turning point in January 1997, the change of trend is largest at southern mid-latitude Lauder, +11%/decade, compared to +7%/decade at northern mid-latitudes. This points to a beginning recovery of upper stratospheric ozone. However, chlorine levels are still very high and ozone will remain vulnerable. At this point the most northerly mid-latitude station, Hohenpeissenberg/Bern differs from the other stations, and shows much less clear evidence for a beginning recovery, with a change of trend in 1997 by only +3%/decade. In fact, record low upper stratospheric ozone values were observed at Hohenpeissenberg/Bern, and to a lesser degree at Table Mountain and Haute Provence, in the winters 2003/2004 and 2004/2005

Aerogel Incorporated Plasters and Mortars: the case study of precast panels

The aim of many current studies regarding building envelopes is the improvement of their thermal resistance. In particular, many attempts have been taken to develop highly insulating materials for advanced building envelopes. The present research investigates the possibility to include aerogels in plaster and mortar products. Several samples of Aerogel Incorporated Plaster and Aerogel Incorporated Mortar were prepared by adding granules of aerogel to different types of plasters and mortars. The thermal conductivity of each sample was then measured by means of a heat flow meter apparatus. In the case of the samples of Aerogel Incorporated Mortar, the mechanical strength and the permeability were tested as well. The results showed that the thermal conductivity and the mechanical strength linearly decreased by increasing the quantity of aerogel added to the mixes. For example, while the control mixture of mortar had a thermal conductivity of 0.28 W/mK and a compressive strength of 50.3 MPa, the mixture of mortar with an addition of 36 vol.% of aerogel halved the thermal conductivity to 0.14 W/mK and reduced the compressive strength to 4.1 MPa. Finally, an Aerogel Incorporated Mortar precast panel was designed and the hygrothermal analysis of the panel was carried out by using WUFI Pro software. Results showed that the thermal transmittance of the panel was reduced by 25% compared to traditional precast panels, which suggested that energy savings and reduced costs during the lifetime of the building could be achieved

Digital Twins nell'Automotive: Una Soluzione Integrata per l'Interazione tra Veicoli, Guidatori e Intersezioni Stradali

Negli ultimi anni, l'industria automobilistica ha assistito a una crescente adozione di tecnologie avanzate, tra cui l'Internet of Things (IoT), l'intelligenza artificiale e i sistemi di monitoraggio in tempo reale. Questi progressi hanno aperto la strada a nuovi paradigmi di sviluppo e gestione dei veicoli, tra cui l'implementazione di Digital Twin ovvero una rappresentazione virtuale in tempo reale di un oggeto fisico o sistema. Questa tesi si propone di esplorare e sviluppare un Digital Twin per veicoli utilizzando un'architettura ad agenti. Gli agenti, entità software autonomi e intelligenti, sono utilizzati per modellare e simulare diverse parti e sistemi del veicolo. Ogni agente ha il compito di rappresentare un componente specifico del veicolo, come il motore, il sistema di frenatura o il sistema di guida autonoma. Questi agenti operano in modo collaborativo per creare una rappresentazione completa e dinamica del veicolo nel mondo virtuale. La tesi esplorerà in dettaglio l'architettura ad agenti utilizzata per creare il Digital Twin del veicolo, discutendo le scelte di progettazione, le tecnologie utilizzate e i casi d'uso specifici. Saranno presentati risultati sperimentali per dimostrare l'efficacia di questa architettura nella simulazione e nell'ottimizzazione delle prestazioni dei veicoli

Il ruolo della nonna nella letteratura per l'infanzia: Da Melina Marchetta a Raquel Díaz Reguera. Proposta di traduzione di "Abuelas. Manual de instrucciones"

El presente trabajo tiene como propósito presentar una reflexión acerca del papel de la abuela en la literatura infantil, junto con la traducción de algunas tablas ilustradas del álbum “Abuelas. Manual de Instrucciones” de la ilustradora-autora española Raquel Díaz Reguera. El primer capítulo ofrece una panorámica del perfil de la abuela en la literatura infantil e incluye el análisis de tres novelas italianas, ejemplificadoras del cambio que el papel de la abuela sufrió entre finales del siglo XX y comienzos del siglo XXI. Se trata de “Terza Generazione” de Melina Marchetta (1999), “Aldabra. La tartaruga che amava Shakespeare” de Silvana Gandolfi (2000), “La nonna di Elena” de Anna Vivarelli (2001). En el segundo capítulo, una breve introducción a la autora Raquel Díaz Reguera así como a la obra “Abuelas. Manual de Instrucciones” anticipa las traducciones que, en cambio, se analizarán y comentarán en el tercer capítulo. El presente trabajo pretende ser un pequeño homenaje a las abuelas, punto de referencia tanto en la sociedad como en la literatura