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One of the key challenges facing organic photodiodes (OPD) is increasing the detection into the IR region. Organic semiconductor polymers provide a platform for tuning the bandgap and optoelectronic response to go beyond the traditional 1000 nm benchmark. In this work, we present a NIR polymer with absorption up to 1500 nm. The polymer-based OPD delivers a high specific detectivity D* of 1.03×1010 Jones (-2 V) at 1200 nm and a dark current Jd of just 2.3×10-6 A cm-2 at -2V. We demonstrate a strong improvement of all OPD metrics in the NIR region compared to previously reported NIR-OPD, due to the enhanced crystallinity and optimized energy alignment which leads to reduced charge recombination. The high D* value in the 1100-1300 nm region is particularly promising for biosensing applications. We demonstrate the OPD as a pulse oximeter under NIR illumination, delivering heart rate and blood oxygen saturation readings in real-time without signal amplification.

Engineering the molecular structure of conjugated polymers is key to advancing the field of organic electronics. In this work, we synthesized a molecularly encapsulated version of the naphthalene diimide bithiophene copolymer PNDIT2, which is among the most popular high charge mobility organic semiconductors in n-type field-effect transistors and non-fullerene acceptors in organic photovoltaic blends. The encapsulating macrocycles shield the bithiophene units while leaving the naphthalene diimide units available for intermolecular interactions. With respect to PNDIT2, the encapsulated counterpart displays an increased backbone planarity. Molecular encapsulation prevents preaggregation of the polymer chains in common organic solvents, while it permits π-stacking in the solid state and promotes thin film crystallinity through an intermolecular-lock mechanism. Consequently, n-type semiconducting behavior is retained in field-effect transistors, although charge mobility is lower than in PNDIT2 due to the absence of the fibrillar microstructure that originates from preaggregation in solution. Hence, molecularly encapsulating conjugated polymers represent a promising chemical strategy to tune the molecular interaction in solution and the backbone conformation and to consequently control the nanomorphology of casted films without altering the electronic structure of the core polymer.

During female lifetime and pregnancy, inflammation and cellular senescence are implicated in physiological processes, from ovulation and menstruation, to placental homeostasis and delivery. Several lifestyles, nutritional, and environmental insults, as well as long-lasting pregestational inflammatory diseases may lead to detrimental effects in promoting and sustaining a chronic excessive inflammatory response and inflammaging, which finally contribute to the decay of fertility and pregnancy outcome, with a negative effect on placental function, fetal development, and future health risk profile in the offspring. Maladaptation to pregnancy and obstetric disease may in turn increase maternal inflammaging in a feedback loop, speeding up aging processes and outbreak of chronic diseases. Maternal inflammaging may also impact, through transgenerational effects, on future adult health. Hence, efficacious interventions should be implemented by physicians and healthcare professionals involved in prevention activities to reduce the modifiable factors contributing to the inflammaging process in order to improve public health.

GaAs/GaInP nanowire solar cells epitaxially grown on a patterned Si substrate feature state-of-the-art open circuit voltage (0.65 V) and quasi-Fermi level splitting (0.84 eV at 1 sun, 1.01 eV at 81 suns), indicating high optoelectronic quality.

Quartz Crystal Microbalances (QCM) are widely used instruments thanks to their stability, low mass, and low cost. Nevertheless, the sensitivity to temperature is their main drawback and is often a driver for their design. Though the crystal average temperature is mostly considered as the only disturbance, temperature affects the QCM measurements also through the in-plane temperature gradients, an effect identified in the past but mostly neglected. Recently, it has been shown that this effect can prevail over that of the average temperature in implementations where the heat for thermal control is released directly on the crystal through deposited film heaters. In this study, the effect of temperature gradients for this kind of crystal is analyzed, the sensitivity of frequency to the average temperature gradient on the electrode border is determined, and a correction is proposed and verified. A numerical thermal model of the QCM has been created to determine the temperature gradients on the electrode borders. The frequency versus temperature-gradient function has been experimentally determined in different thermal conditions. The correction function has been eventually applied to a QCM implementing a crystal of the same manufacturing lot as the one used for the characterization. The residual errors after the implementation of the correction of both average temperature and temperature gradients were always lower than 5% of the initial temperature disturbance. Moreover, using the correlation between the heater power dissipation and the generated temperature gradients, it has been shown that an effective correction strategy can be based on the measurement of the power delivered to the crystal without the determination of the temperature gradient.

Space is one of the most avant-garde sectors for additive manufacturing as the inherent characteristics of this technology allow the creation of complex and lightweight 3D structures. Using this brand-new design tool, it was possible to design the pumping system holder of the MicroMED instrument, a particle analyser developed for ExoMars 2022 mission. The geometry of the holder was optimized using a finite element approach. The effectiveness of the proposed solution was evaluated by comparing the performance of two different designs using the AlSi9Cu3 alloy. One solution was based on micro-milling and the other on Selective Laser Melting. In order to validate the designed SLMed holder, a mockup was produced and successfully tested in the mission's mechanical environment.

Introduction: The Solar System dust is the smallest Solar System building block, and therefore its study allows understanding the early stages of the Solar System formation. The comprehension of the Solar System formation and evolution processes is also constrained by the inventory and spatial distribution of volatiles in our System. In particular, the delivery process of volatiles of astrobiological interest (water and organics) to the Earth is a key issue to understand the life formation in our planet. Asteroids and comets may have been the source of these volatiles to the terrestrial planets’ atmospheres and to the Earth’s oceans. The boundary between asteroids and comets is not well defined, and many main-belt asteroids are probably volatile-rich and would become cometary if they were moved to the inner Solar System. Piezoelectric Crystal Microbalances (PCMs) are widely used sensors to monitor dust and particles deposition processes in space and to characterize material outgassing in vacuum. This kind of sensors converts mass changes into fundamental resonance frequency variations, according to Sauerbrey equation [1]. In this work we present VISTA (Volatile in-Situ Thermogravimeter Analyser), one of the two scientific payloads on board MILANI Cubesat, as part of the ESA Hera Program. The MILANI Cubesat development is led by Tyvak International, prime contractor of a consortium composed by entities and institutions from Italy, Czech Republic and Finland. The main MILANI objective is executing a scientific mission aiming at studying the binary asteroid system Didymos-Dimorphos, characterizing the asteroid with a dust sensor, i.e. VISTA, and a spectrometer, i.e. ASPECT. VISTA is developed by an Italian Consortium composed by three Research Institutes: INAF-IAPS (National Institute of Astrophysics - Institute for Space Astrophysics and Planetology), CNR-IIA (National Council of Research – Institute of Atmospheric Pollution) and Politecnico di Milano. HERA Mission goals: Hera is a planetary defence mission under development at the European Space Agency (ESA), launching in October 2024. Hera is the European contribution to the international Asteroid Impact Deflection Assessment (AIDA) cooperation, the first planetary defence mission, in collaboration with NASA, who is responsible for DART (Double Asteroid Redirection Test) kinetic impactor spacecraft. Hera will travel to a binary asteroid system, the Didymos-Dimorphos pair of near-Earth asteroids, and will study and characterize the asteroid system after the DART impact in September 2022. In the framework of Hera mission, VISTA will accomplish the following scientific goals: 1) detect the presence of dust particles smaller than 10 µm (residual dust particles from the impact and suspended dust in the binary system or coming from dust levitation process); 2) characterization of volatiles (e.g. water) and light organics (e.g. low carbon chain compounds) by using Thermo-Gravimetric Analysis (TGA) cycles (the desorption rates ad specific temperatures are used to characterize e volatiles and organics desorbed from the sensor surface); 3) molecular contamination monitoring in support to other Cubesat instruments and ASPECT spectrometer, coming from outgassing processes on-board the spacecraft, that usually happen in the first days or weeks in orbit. VISTA Heritage: The Consortium has a considerable heritage in the design, manufacturing and testing of PCM-based instrumentation both for laboratory and space applications coming from different ITT-Emits ESA Projects: 1) CAM (Contamination Assessment Microbalance), developed for “Evaluation of an in-situ Molecular Contamination Sensor for space use” (2014-2016) (Figure 1); 2) CAMLAB (Contamination Assessment Microbalance for LABoratory) developed for “Development of a European Quart Crystal Microbalance” (2017-2019) (Figure 2). Figure 1. PCM Engineering Model developed during CAM-ESA Project for space applications. Figure 2. PCM breadboard developed during CAMLAB-ESA Project for laboratory applications. Working principle: PCMs exploit the piezoelectric properties of quartz crystals, as mass deposition on the sensing area of the instrument induces variations of the crystal resonance frequency. The core of VISTA is composed of: 1) two quartz crystals mounted in a sandwich-like configuration (one sensing crystal and the other reference crystal); 2) a Thermal Control System (TCS), composed by two integrated heaters and a Thermoelectric Cooler (TEC); 3) a Proximity Electronics (PE). The instrument is also capable of performing Thermo-Gravimetric Analysis, a technique used to monitor thermal processes involving volatile compounds, e.g absorption/desorption and deposition/sublimation, by means of the built-in heaters. The TEC is used to cool down the sensor and enhance the condensation of particles on the microbalance. VISTA is capable of monitoring particles lower than 5-10 µm and sub-µm particles. VISTA technical characteristics are shown in Table 1. Table 1. VISTA technical characteristics. The sublimated compounds can be characterized by calculating the enthalpy of sublimation ΔHsub, which can be retrieved with two methods: 1) by considering the deposition rates and using Van’t Hoff relation [3]; 2) by using Langmuir relation [4]. Conclusions and future works: In this work, the VISTA instrument working principle and heritage were presented. Qualification activities are currently ongoing on the VISTA Engineering Qualification Model (EQM), shown in Figure 3, in order to qualify the sensor within the expected mechanical and thermal environment and evaluate the instrument performances in a representative environment, prior integration on the MILANI Cubesat. The next phase of the research activities will be the manufacturing, integration and testing of VISTA Flight Model (FM), that will launch in 2024. Figure 3. VISTA EQM developed for MILANI cubesat/HERA Space Mission. References: [1] G. Sauerbrey 1959, Z. Phys., 155, 206-222; [2] Palomba E. (2016), OLEB, 46 (2-3); [3] S.W. Benson et al. 1968; [4] I. Langmuir, 1913.

Introduction: Quartz Crystals Microbalances (QCMs) are widely used sensors for monitoring and characterizing dust and particles deposition processes in different planetary environments and measuring material contamination coming from outgassing sources in space, in support to other instruments (e.g. spectrometers). Furthermore, they are capable of detecting and measuring the presence of volatile com-pounds of astrobiological interest such as water and organics. These measurements can be particularly relevant when performed on primitive asteroids or comets, or on targets of potential astrobiological interests, e.g. Mars [1]. These sensors convert mass changes into fundamental resonance frequency variations, according to Sauerbrey equation [2]. The VISTA (Volatile In Situ Thermogravimetry Analyser) instrument is a QCM-based device able to perform measurements of abundance of volatiles and dust particles in planetary and asteroidal environments. The instrument can characterize the planetary regolith from 5-10 µm to sub-µm particles and monitor the contamination processes on board satellites (cubesat, etc.) caused by molecular outgassing. VISTA is one of the two scientific payloads of MILANI CubeSat, developed by Tyvak International that leads a consortium composed by entities and institutions from Italy, Czech Republic and Finland, in the framework of the Hera program of the European Space Agency (ESA). Hera, due to launch in 2024, is the ESA part of the Asteroid Impact & Deflection Assessment (AIDA) international collaboration with NASA, who is responsible for the Double Asteroid Redirection Test (DART) kinetic impactor spacecraft. The main objective of MILANI is the study of the binary asteroid system Didymos-Dimorphos, characterizing the asteroid with a dust sensor (VISTA) and a spectrometer (ASPECT). In this work, the calibration operations and the performance tests, to assess VISTA capability of characterizing volatile compounds and simulant contaminations in vacuum chamber at low temperatures. The sensor has been developed by an Italian Consortium composed by three Research Institutes: INAF-IAPS (National Institute of Astrophysics - Institute for Space Astro-physics and Planetology), CNR-IIA (National Council of Research – Institute of Atmospheric Pollution) and Politecnico di Milano and led by INAF-IAPS. Figure 1. VISTA EQM developed for ESA Hera space mission. Working Principle: The instrument core is a QCM whose frequency variations directly depends on the deposited sample mass on the crystal surface during sublimation, condensation and absorption/desorption processes. The instrument consists of: 1) two quartz crystals mounted in a sandwich-like configuration; 2) a Thermal Control System (TCS), composed by two integrated heaters and a Thermoelectric Cooler (TEC); 3) a Proximity Electronics (PE). VISTA is also capable of performing Thermo-Gravimetric Analysis, which is a technique used to monitor thermal processes involving volatile compounds, e.g. deposition/sublimation and absorption/desorption. It can also monitor particles lower than 5-10 µm and sub-µm particles [1]. Calibration: The QCM frequency can change not only due to the mass deposition/release, but also due to the variation of environmental parameters, such as temperature and pressure. In order to disentangle frequency variations due to mass deposition and environmental parameters, the sensor is calibrated by measuring the frequency as a function of temperature. According to literature [3], the frequency-temperature curve follows a third-degree polynomial (Figure 2). Figure 2. QCM frequency as a function of temperature in vacuum. Performance tests: VISTA capability to detect contaminant depositions and to monitor the accumulation and desorption processes is verified by placing an effusion cell containing an organic compound, used as a contamination source, placed in the Field Of View (FOV) of the sensing crystal and heated up to 100°C. The experimental setup is shown in Figure 3. Figure 3. VISTA EQM experimental setup for contamination simulation. The QCM is connected with four screws with a copper U shape and in contact with a cold sink set to -10°C to help the molecules condensation on the crystal surface. The frequency is monitored during the tests and the deposited flux can be retrieved (Figure 4) at each temperature set point. Figure 4. Deposition test from +50°C to +100°C. Two methods can be used to retrieve the enthalpy of sublimation ΔHsub by using the deposition rates, i.e. the Van’t Hoff relation [4] or Langmuir relation [5]. Thus, by measuring two different deposition rates, k1 and k2, at two different close temperatures T1 and T2, it is possible to obtain the compound ΔHsub by means of Van’t Hoff relation or throughout the temperature range by using Langmuir relation. TGA cycles are then performed by heating the crystals by means of the built-in heaters. After the heating cycles, the frequency returns to its initial value, thus indicating that all the deposited mass desorbed during the test (Figure 5). Figure 5. TGA cycles from +15°C to +50°C and from +40°C to +70°C. The desorption rates from crystals surface can be used as well to calculate the ΔHsub and compare it with the ΔHsub results obtained during the depositions/contamination processes. References: [1] E. Palomba et al (2016), OLEB, 46(2-3; [2] G. Sauerbrey (1959), Z. Phys., 155, 206-222; [3] D. Salt (1987); [4] S.W. Benson et al., 1968; [5] I. Langmuir, 1913.

The composition of the Martian atmosphere and its dust content is a key factor for understanding the climate of the Red Planet, which is of vital importance to enable future human exploration. The use of atmospheric LIDARs to characterize densities and sizes of aerosol with a height profile, is commonly used on Earth. However, Earth LIDARs are heavy and very power-demanding, which make them not easily on-boardable for planetary exploration. We propose the development of a compact LIDAR aimed at providing the most precise characterization of the suspended dust and clouds of the atmosphere of Mars to-date, while maintaining very reduced power, mass and volume envelops to facilitate its accommodation in a wide variety of landed assets. Rationale and heritage In the past years, INTA has developed four miniature radiometers for different missions: MetSIS for MetNet Lander [1], DREAMS-SIS for Schiaparelli [2], SIS’20 for Kazachok [3] and RDS for Perseverance [4]. All of them, at different levels depending on their complexity, allow the estimation of the atmospheric optical depth with high time resolution, detection of clouds and estimation of the dust concentration vertical profile. A natural step forward to complement our capabilities, especially for the dust profile and characterization of clouds, is a LIDAR. There is only one LIDAR that has already operated on Mars, on board the Phoenix mission. With a 2-wavelengths configuration at 532 and 1064 nm but without depolarization, it operated in the North Pole of Mars for 90 sols [5]. The laser pulses had a power of 30-40 kW and duration of 10 ns. Total mass was 6 kg and the power consumption 30W. A '2B+1d' LIDAR configuration is proposed here to obtain the Particle Backscatter Coefficient (PBC) at two wavelengths (2B), and the depolarization ratio at one of them (1d). They both are used to obtain three LIDAR parameters relevant for dust and cloud characterization: the particle linear depolarization ratio (PLDR), the lidar ratio (LR), and the colour ratio (CR). The intended range is set around 20 km, depending on the scenario, and depolarization measurement capability shall be incorporated. Key technologies for miniaturization The target mass and power envelop are Pulsed semiconductor laser diodes are proposed for the transmitter, instead of usual (and bulkier) diode-pumped, Q-switched solid-state lasers. This reduces the emitted energy and in turn requires higher repetition rates to improve the Signal-to-Noise ratio. Silicon Photomultipliers, also known as Multi Pixel Photon Counters, will be used as detectors. They allow lower biasing voltages than other high-gain technologies, while they show some trade-offs such as their so-called "cross talk" noise. Its performance under the applicable thermal and radiation environments must be addressed. The use of new synthesis methods to obtain very low thermal expansion coefficient (CTE) materials (crystalline β- eucryptite) to reduce the thermal requirements related to structure and alignment. To reduce the size of the optics and to mitigate the complexity of the collimation of a semiconductor laser (with large spots and emission apertures), 'free form' optics will be considered in the optical design. From the signal processing point of view, the aim is to design a receiver that autonomously adapts the measurement mode (analogue or pulse counting) and parameters (e.g., variable time intervals for pulse-counting) in real time, providing the best signal quality vs. vertical resolution compromise for each altitude. Feasibility To preliminarily assess the feasibility of this LIDAR to reach a scientifically meaningful range, we have performed several simulations of the expected signal and signal-to-noise ratio using extinction and backscattering profiles representative of different dust conditions on Mars, together with technical data extracted from the datasheets of real pre-selected parts and opto-mechanical parameters values that we consider feasible for a compact instrument as the intended one. Emitted pulses have a power of 600W and a duration of 150ns. We have simulated three different background illumination scenarios: night, twilight, and midmorning, as this is critical from the point of view of the “offset” signal it generates (that must be filtered out) and the noise associated with it. We employed worst-case (high) diffuse radiance values on Mars. Extinction and backscattering coefficients have been extracted from Phoenix LIDAR measurements [6], and background illumination values from RDS measurements in Perseverance. The conclusion is that, with adequate signal processing, we should be capable of reaching 4 km during the day, 6-7 at twilight and 15 at night, for the worst-case scenario. 20 km are feasible in better scenarios. On-going activity and next steps A breadboard prototype of the system is being built at INTA for only one channel (one wavelength; no polarization) based on pre-selected pulsed laser diode and silicon photomultiplier, with standard off-the-shelf optical parts and filters. Preliminary laboratory and outdoor measurements will be done to validate the simulations and confirm the feasibility of reaching a meaningful range with the strict miniaturization constraints. Low-temperature characterization of the emitters and detectors, as well as Displacement Damage tests to assess their robustness to the radiation environment will be done by the end of the year. The electronic design has a large heritage from previous Martian sensors as the ones mentioned above, all of them designed to operate down to -130ºC with no heating. Next steps will include thermal cycling testing of the optics and the support materials and feasibility analysis of the optomechanical frame to face such conditions. [1] Ari-Matti Harri et al., Geosci. Instrum. Method. Data Syst., 6, 103–124, 2017. [2] I. Arruego et al., Advances in Space Research 60 (2017) 103–120. [3] I. Arruego, Proc. IPPW 2018. [4] V. Apéstigue et al., Sensors 2022, 22, 2907 [5] J. A. Whiteway et al., Journal Geophys. Res., Vol. 113, E00A08. [6] J. A. Whiteway, et al., Science 325, 68 (2009).

This study measures territorial competitiveness at the municipal level in Italy, by proposing a robust composite indicator based on variables not yet used in the literature. The underlying theoretical framework is identified based on the literature on regional competitiveness. The proposed indicator consists of the following seven dimensions of competitiveness: Education, Job, Economic Wellbeing, Territory and Environment, Entrepreneurship, Innovation, and Infrastructures and Mobility. Data are retrieved mainly from administrative sources, for 2014 and 2015. In the building process, three aggregation methods are compared: a compensatory method, the arithmetic mean, and two partially compensatory methods, the geometric mean and the Adjusted Mazziotta-Pareto Index (AMPI). The arithmetic mean turns out to be the most robust method among the three considered, but the AMPI is the most robust method among the two partially compensatory methods. All the methods considered agree in identifying Innovation and Entrepreneurship as the most influential pillars in 2014 and 2015, respectively. The detailed geographical focus provides specific insights into territorial competitiveness in Italy. It emerges a rather heterogeneous picture of municipal competitiveness within the Italian regions. Highly competitive municipalities are present in every region, though with different concentration levels.

Quartz crystal microbalances are widely used sensors with applications for the detection of very-low-mass deposition in many different fields, from contamination monitoring in the high vacuum of deep space missions to the monitoring of biological activity or pollution using specifically designed active substrates. These sensors are very stable over time; nevertheless, their sensitivity to the temperature is well known, and different implementations have been devised to correct it, e.g., through compensation with a dual crystal. This paper deals with the effects of temperature on QCM but separates the case of uniform crystal temperature from the case of in-plane temperature gradients considering a QCM based on quartz crystals with deposited film resistors used as both RTDs and heaters. This configuration allows both an accurate temperature measurement and efficient thermal control, allowing the achievement of crystals temperatures in the order of 400 °C higher than the environment with a low power dissipation of the order of 1 W. The film resistors deposited around the electrodes allow directly measuring the average crystal temperature and directly delivering power to the crystal for thermal control. The localized delivery of the heat nevertheless also determines uncommon temperature fields on the crystal, and thus, an analysis of both the effects of temperature on the new microbalance was performed. The temperature gradient has strong effects on the frequency; therefore, along with the temperature, the thermal gradients have tobe compensated. The calibration of the QCM thermometers and the assessment of the achievable measurement accuracy were performed, as well as the determination of the frequency–temperature relationship. The comparison between frequency changes in the case of uniform temperature and those observed while using crystal heaters proved that temperature gradients have a strong effect on the crystal frequency. To identify the temperature field on the crystal surface of a QCM crystal, the gold coating of the deposited films was removed to achieve an emissivity acceptable for thermal imaging with an IR camera. Moreover, image processing for emissivity correction was developed. In order to correlate the temperature gradient with the frequency variation, a test campaign was performed to measure the frequency changes derived from different power levels delivered to the crystal heaters. From this test campaign and thermal analysis, the effect of the thermal gradient was assessed.

With their unique structural, optical and electrical properties, III-V nanowires (NWs) are an extremely attractive option for the direct growth of III-Vs on Si for tandem solar cell applications. Here, we introduce a core-shell GaAs/GaInP NW solar cell grown by molecular beam epitaxy on a patterned Si substrate, and we present an in-depth investigation of its optoelectronic properties and limitations. We report a power conversion efficiency of almost 3.7%, and a state-of-the-art open-circuit voltage (

Flowers have many sensory traits to appeal to pollinators, including ultraviolet (UV) absorbing markings, which are well known for attracting bees at close proximity (e.g. < 1 m). While striking UV signals have been thought to attract pollinators also at greater distances of meters, how the signals impact the plant pollination success over distance remains unknown. Here we report the case of the Australian orchid Diuris brumalis, a non-rewarding species, pollinated by bees via mimicry of rewarding pea plant Daviesia decurrens. When distant from the pea plant, Diuris brumalis was hypothesized to enhance pollinator attraction by exaggerately mimicking the floral ultraviolet (UV) reflecting patterns of its model.By experimentally modulating floral UV reflectance with a UV screening solution, we quantified the orchid pollination success at variable distance from the model plants.We demonstrate that the deceptive orchid Diuris brumalis attracts bee pollinators by emphasizing the visual stimuli, which mimic the floral UV signalling of the rewarding model D. decurrens. Moreover, the exaggerated UV reflectance of D. brumalis flowers impacted pollinators’ visitation at an optimal distance from D. decurrens, and the effect decreased when orchids were too close or too far away from the model.Our findings show that salient UV flower signalling plays a functional role in visual floral mimicry, likely exploiting perceptual gaps in bee neural coding, and mediates the plant pollination success at much greater spatial scales than previously expected.

The combination of computational methods and advanced characterization techniques is used to highlight the role of the intramolecular hydrogen bond in thienyldiketopyrrolopyrrole (ThDPPTh) copolyme...

Doping is a common strategy in the field of semiconductor technology but its employment in organic photodetectors (OPDs) has been limited due to the typical uncontrollable increase of the dark currents. This study introduces three different molecular dopants, including p-type tris(pentafluorophenyl)borane, n-type benzyl viologen, and (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)-phenyl)dimethylamine, for near-infrared poly[[2,5-bis(2-hexyldecyl)-2,3,5,6-tetrahydro-3,6-dioxopyrrolo[3,4-c]pyrrole-1,4-diyl]-alt-[3′,3′′-dimethyl-2,2′:5′,2′′-terthiophene]-5,5′′-diyl]:[6,6]-phenyl C61 butyric acid methyl ester (PMDPP3T:PC61BM) bulk-heterojunction OPDs. The results show that OPDs with optimal 0.02 wt% dopants exhibit low dark current (3.18 × 10−8 A cm−2), high detectivity (5.56 × 1012 Jones), and good environmental stability for ∼2 months. These doped OPDs are further used for pulse wave monitoring, which exhibit stable waveforms and can distinguish slow and fast heartbeat rates.

Atom-economic protocols for the synthesis of poly(indacenodithiophene-alt-benzothiadiazole) (PIDTBT) are presented in which all C–C coupling steps are achieved by direct arylation. Using two different synthetic pathways, PIDTBT copolymers with different side chains (hexylphenyl, octylphenyl, dodecyl, methyl/2-octyldodecylphenyl, 2-octyldodecylphenyl/2-octyldodecylphenyl) and molecular weight (MW) are prepared. Route A makes use of direct arylation polycondensation (DAP) of indacenodithiophene (IDT) and 4,7-dibromo-2,1,3-benzothiadiazole (BTBr2) leading to PIDTBT in high yields, with adjustable MW and without indications for structural defects. Route B starts from a polyketone precursor also prepared by DAP following cyclization. While route B allows introduction of asymmetric side chains at the IDT unit, polymer analogous cyclization gives rise to defect formation. The absorption coefficient of PIDTBT with alkylphenyl side chains made by route A increases with MW. Field-effect hole mobilities around ∼10−2 cm2 V−1 s−1 are molecular weight-independent, which is ascribed to a largely amorphous thin film morphology. PIDTBT with linear dodecyl side (C12) chains exhibits a bathochromic shift (20 nm), in agreement with theory, and more pronounced vibronic contributions to absorption spectra. In comparison to alkylphenyl side chains, C12 side chains allow for increased order in thin films, a weak melting endotherm and lower energetic disorder, which altogether explain substantially higher field-effect hole mobilities of ∼ 10−1 cm2 V−1 s−1.

Background: The sustainability of palliative care services is nowadays crucial inasmuch as resources for palliative care are internationally scarce, the funding environment is competitive, and the potential population is growing. Methods: The DEMETRA study is a multicentre prospective observational study, describing the intensity of care and the related costs of palliative home care pathways. Results: 475 patients were enrolled as recipients of specialized palliative home care. The majority of recipients were cancer patients (89.4%). The mean duration of palliative care pathways was 46.6 days and mean home care intensity coefficient equal to 0.6. The average daily cost of the model with the reference variables is 96.26 euros. Factors statistically significantly associated with an increase in mean daily costs were greater dependence and extreme frailty (p < 0.05). Otherwise, a longer duration of treatment course was associated with a significant decrease in mean daily costs (p < 0.001). Conclusions: In terms of clinical and organizational management, considering the close association with the intensity and cost of the path, frailty should be systematically assessed by all facilities that potentially refer patients to home palliative care teams, and it should be carefully recorded in a standardized payment rate perspective.

Molecular doping has recently been shown to improve the operating characteristics of organic photovoltaics (OPVs). Here, we prepare neutral Diquat (DQ) and use it as n-dopant to improve the perform...

Despite their diversity and the potential for specialized pollination systems, Australian Fabaceae have received little attention in pollination studies. In the Southwest Australian Floristic Region (SWAFR), a recognized biodiversity hotspot, co-occurring and abundant species of Faboideae exhibit a range of floral colours and forms, suggestive of adaptation to different groups of pollinators. For four communities of Fabaceae in the SWAFR we investigated whether co-occurring species overlap in pollinator genera, whether these pollinators show differences in behaviour on the pea flower and whether variations in stamen length and nectar composition among species are associated with different pollinator types. Species of Fabaceae were visited by one to four genera of native bees, suggesting varying levels of ecological specialisation. In Fabaceae with more specialized interactions, co-occurring species showed marked differences in the bee genera attracted. Unexpectedly, some Fabaceae frequently attracted beetles, which may play an important role in their pollination. There was no evidence for an association between stamen length or nectar composition and the type of pollinator. The introduced honeybee, visited all studied species of Fabaceae, suggesting that they may act both as a pollinator and a potential competitor with native pollinators.

The sudden worldwide outbreak of Coronavirus Disease 2019 (COVID-19) has certainly provided new challenges in the management of acute ischaemic stroke, and the risk-benefit ratio of intravenous thrombolysis in COVID-19 positive patients is not well known. We describe four COVID-19 patients treated with intravenous thrombolysis for acute ischaemic stroke. Although rt-PA administration is the main therapeutic strategy, our patients experienced unpredictable complications and showed atypical features: the overall mortality was very high. In conclusion, in this article, we provide information about these cases and discuss the possible explanation behind this trend.

During the restoration of the Duomo di Milano main spire, a monitoring system has been set up in order to have an early detection of potential risks of the spire. A scaffolding for the restoration activities was mounted around the spire, and it had a section exposed to the wind actions much wider than the spire itself. Any possible contact between the spire and the scaffolding had to be prevented, even under the strongest winds expected in Milan, since the stability of the extremely slender marble spire could be compromised in case of contact. A safety gap between the two substructures was granted during the construction phase; however, the deflection of the spire could not be reliably predicted by numerical models. Therefore, it was decided to continuously monitor the actual gap value, together with other measurements, helping in a thorough understanding of the spire and scaffolding movements. The gap monitoring was measured by three-wire potentiometers, mounted to measure the relative position between the scaffolding and the spire in the section where the gap was the narrowest: the top balcony. This measurement was considered one of the most critical for the safety of the spire; therefore, every choice has been aimed at redundancy and safety. Moreover, any systematic effect has to be compensated for. A main issue related to the use of wire potentiometers is that these sensors estimate the amplitude of the displacement but does not provide any information on its direction. Since the horizontal displacement of slender structures can be in any direction, according to the wind and sun radiation conditions, the output of a wire potentiometer is also affected by displacements in the direction normal to its sensitivity axis, leading to a systematic effect in the measurements (cross-talk effect). This aspect hardly finds literature attention, but it can play a major role if the safety of the structure is monitored with wire potentiometers. This paper focuses on the estimation and compensation of this cross-talk effect, to provide reliable measurements in the monitoring of slender structures. Numerical and experimental validation of the proposed approach demonstrates the need to compensate for the cross-talk effects for a proper uncertainty estimation and then the validity of the proposed method.

Blade-coating is a roll-to-roll (R2R) compatible processing technique and has the potential to address the industry's needs for scalable manufacturing of future organic electronics. Here we investigate the applicability of blade-coating for the fabrication of organic thin-film transistors (OTFTs) based on best-in-class organic semiconducting blends comprised of the conjugated small-molecule 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT), and the conjugated polymer poly(indacenodithiophene-co-benzothiadiazole) (C16IDT-BT). We show that the operating characteristics of blade-coated transistors consistently outperform devices prepared via spin-coating, showcasing the compatibility of the technique. Introducing the molecular p-dopant C60F48 into the binary C8-BTBT:C16IDT-BT blend formulation, in combination with carefully optimized blade-coating conditions, helps to enhance the performance of the ensuing transistors further resulting in a maximum hole mobility of ≈14 cm2 V−1 s−1, and an all-around improvement of the device operating characteristics. Our results show that p-doped blend OTFTs can be manufactured using industry relevant processing techniques without sacrificing their state-of-the-art performance.

International audience; We report the first investigation of indium (In) as the vapor-liquid-solid catalyst of GaP and GaAs nanowires by molecular beam epitaxy. A strong asymmetry in the Ga distribution between the liquid and solid phases allows one to obtain pure GaP and In 0.2 Ga 0.8 As nanowires while the liquid catalyst remains nearly pure In. This uncommon In catalyst presents several advantages. First, the nanowire morphology can be tuned by changing the In flux alone, independently of the Ga and group V fluxes. Second, the nanowire crystal structure always remains cubic during steady state growth and catalyst crystallization, despite the low contact angle of the liquid droplet measured after growth (95 •). Third, the vertical yield of In-catalyzed GaP and (InGa)As nanowires arrays on patterned silicon substrates increases dramatically. Combining straight sidewalls, controllable morphologies and a high vertical yield, In-catalysts provide an alternative to the standard Au or Ga alloys for the bottom-up growth of large scale homogeneous arrays of (InGa)As or GaP nanowires. We note that the SET and NT curves nearly coincide over all 78 the explored composition range. This typical of NW growth and 79 was already observed by Glas on [Ga]-(AlGa)As NWs 34. It relates 80 to the low concentration of group V in the liquid catalyst, as com-81 puted using SET (see Supplementary Information †) or deduced 82 from other experiments 36. 83 From both NT and SET, we find that the Ga distribution is 84 strongly asymmetric. This particular Ga distribution is not unique 85 to our system and similar curves were calculated for ternary 86 [Au]-(InGa)As NWs using NT 25. These fast changes in the solid 87 (x) at near constant liquid composition (y) are often hindering 88 the fabrication of NW with uniform composition. Yet, away from 89 these abrupt changes, the solid composition varies slowly over 90 large ranges of liquid composition. Most relevant to the present 91 work, Ga contents (x) in solid In 1−x Ga x P and In 1−x Ga x As reach 92 near unity while the Ga fractions (y) in the liquid remain below 93 a few atomic percents. Hence the VLS growth of nearly pure GaP 94 and GaAs NWs from nearly pure In catalyst seems achievable. 95 3 Steady state growth 96 In light of the above calculations, we have proceeded to grow 97 [In]-(InGa)P and [In]-(InGa)As NWs on patterned Si(111) sub-98 strates using MBE (see experimental). Both In and Ga atoms are 99 supplied continuously to sustain the NW growth so that In evap-100 oration is compensated and the catalyst composition remains In-101 rich. Compared to [Ga]-GaAs or [Ga]-GaP NWs, typically grown 102 at 600 • C 15,36 , the substrate temperature is reduced to 520 • C to 103 limit the evaporation of In adatoms. Identical Si(111) wafers with 104 hexagonal arrays (300 nm pitch) of 50 nm diameter holes in a 105 14 nm thick silica mask are used to grow selectively the GaAs and 106 GaP NWs. The details of the growth and patterning procedures 107 can be found in the experimental section.

Here we have investigated the influence of the molecular length and structure of a series of BTI-based semiconductors on the stabilization of charged states in solution by in situ UV/Vis/NIR spectroelectrochemistry and in the solid state, at the active interface of operational OFET devices, by charge modulation spectroscopy (CMS). Interestingly, we found that charge stabilization in the shortest system of the series (BTI2) is strongly favored via a π-dimer formation which, in addition to higher thin film microstructural ordering, results in a greater electron mobility in organic field effect transistors (OFETs). The experimental results were interpreted using TD-DFT and DFT quantum chemical calculations at different levels of theory.

Organic electronics has been steadily evolving, with improving performances, including unrivaled mechanical properties. One of the main technological trends aims at thinner and lighter form factors, toward the realization of ultraflexible and conformable large-area electronic devices, capable of withstanding harsh mechanical stresses and therefore finding applications where rigid or brittle technologies would fail. Pursuing this objective, a critical role is known to be played by the substrate, whose thickness needs to be reduced as much as possible while maintaining its processability. Ultrathin substrates and a neutral plane strategy have therefore been exploited to realize ultrathin organic devices; however, ultraflexible complementary circuits based on printed organic semiconductors, realized by means of high-throughput and large-area techniques, have not been realized so far. In this work, all-polymer organic field effect transistors and complementary inverters have been printed onto a micrometer-thin parylene substrate, subsequently also used as a top isolation layer in order to place the active components in the neutral plane of stresses. These devices show appropriate low voltage operation, with supply voltages as low as 2 V, and retain stable and uniform performances upon the application of harsh mechanical stresses, such as rolling and crumpling. These results represent the first demonstration of semi-transparent and fully organic crumpable printed electronics, and pave the way toward the realization of more complex complementary logic circuits, laying the foundation for their widespread and cost-effective integration into consumer products.

This paper documents a thermo-fluid-dynamic mean-line model for the preliminary design of multistage axial turbines with blade cooling applicable to supercritical CO2 turbines. Given the working fluid and coolant inlet thermodynamic conditions, blade geometry, number of stages and load criterion, the model computes the stage-by-stage design along with the cooling requirement and ultimately provides an estimate of turbine efficiency via a semi-empirical loss model. Different cooling modes are available and can be selected by the user (stand-alone or combination): convective cooling, film cooling, and thermal barrier coating. The model is applied to attain the preliminary aero-thermal design of the 600 MW cooled axial supercritical CO2 turbine of the Allam cycle. Results show that a load coefficient varying from 3 to 1 throughout the machine, and a reaction degree ranging from 0.1 to 0.5 lead to the maximum total-to-static turbine efficiency of about 85%. Consequently, as opposed to uncooled CO2 turbines, a repeated stage configuration is an unsuited design choice for cooled sCO2 machines. Moreover, the study highlights that film cooling is considerably less effective compared to conventional gas turbines, while increasing the number of stages from 5 to 6 and adopting higher rotational speeds leads to an increased efficiency.

The organic electronics research field has advanced tremendously in the last decades, already rendering semiconductors able to compete with their inorganic counterparts. However, the final blossoming of this field would probably come with the complete understanding of the charge transport mechanism in organic materials. For this end, spectroscopies techniques have been proven to be of great interest in the elucidation of the different processes taking place in electronic devices. These techniques, and in particular Raman spectroscopy is a rapid, noninvasive technique able to gather information on molecular and supramolecular levels, thus being really useful for this purpose. In this talk, some examples from our research group will be presented in which several spectroscopic techniques, supported by DFT quantum chemical calculations have been used to shed light on the charge transport mechanisms in organic field effect transistors (OFETs). Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The low carrier mobility of organic semiconductors and the high parasitic resistance and capacitance often encountered in conventional organic Schottky diodes, hinder their deployment in emerging radio frequency (RF) electronics. Here we overcome these limitations by combining self-aligned asymmetric nanogap electrodes (∼25 nm) produced by adhesion-lithography, with a high mobility organic semiconductor and demonstrate RF Schottky diodes able to operate in the 5G frequency spectrum. We used C16 IDT-BT, as the high hole mobility polymer, and studied the impact of p-doping on the diode performance. Pristine C16 IDT-BT-based diodes exhibit maximum intrinsic and extrinsic cutoff frequencies (fC ) of >100 and 6 GHz, respectively. This extraordinary performance is attributed primarily to the planar nature of the nanogap channel and the diode's small junction capacitance (< 2 pF). Doping of C16 IDT-BT with the molecular p-dopant C60 F48 , improves the diode's performance further by reducing the series resistance resulting to intrinsic and extrinsic fC of >100 and ∼14 GHz respectively, while the DC output voltage of a RF rectifier circuit increases by a tenfold. Our work highlights the importance of the planar nanogap architecture and paves the way for the use of organic Schottky diodes in large-area radio frequency electronics of the future. This article is protected by copyright. All rights reserved.

There is a growing demand to attain organic materials with high electron mobility, μ e, as current reliable reported values are significantly lower than those exhibited by their hole mobility counterparts. Here, it is shown that a well‐known nonfullerene‐acceptor commonly used in organic solar cells, that is, BTP‐4F (aka Y6), enables solution‐processed organic thin‐film transistors (OTFT) with a μ e as high as 2.4 cm2 V−1 s−1. This value is comparable to those of state‐of‐the‐art n‐type OTFTs, opening up a plethora of new possibilities for this class of materials in the field of organic electronics. Such efficient charge transport is linked to a readily achievable highly ordered crystalline phase, whose peculiar structural properties are thoroughly discussed. This work proves that structurally ordered nonfullerene acceptors can exhibit intrinsically high mobility and introduces a new approach in the quest of high μ e organic materials, as well as new guidelines for future materials design., n‐channel organic thin‐film transistors exhibiting electron mobility values as high as 2.4 cm2 V−1 s−1 are produced with the benchmark nonfullerene acceptor used in organic solar cell, that is, BTP‐4F (aka Y6). These properties stem from crystallization of Y6 in a crystalline structure featuring molecularly flat, highly ordered, and textured domains.

Background Pediatric palliative care (PPC) addresses the physical and psychological needs of children suffering from life-limiting diseases. To define prevention and educational plans and to properly allocate resources, a precise estimation of the PPC burden is required. Objectives To estimate the current number of children requiring PPC in Italy, useful to assist policy-makers and healthcare bodies in the organization and allocation of PPC resources. Methods Literature data, The Global Atlas of Palliative Care at the End of Life and Italian national databases have been consulted. Results According to our estimation, at present, a total of 20,540–32,864 children in Italy require PPC (34–54 children/100,000 inhabitants) of whom 18 children/100,000 inhabitants require specialized PPC. Conclusions The present work is a fundamental tool to be used by the institutions, the local networks of PPC and the health programmers when formulating organizational models and care plans consistent with the actual need for PPC.

ObjectivesThe aim of this work is to describe the multidisciplinary model of intervention applied and the characteristics of some COVID-19 patients assisted by the hospital palliative care unit (UCP-H) of an Italian hospital in Lombardy, the Italian region most affected by the COVID-19 pandemic.MethodsA retrospective study was conducted on patients admitted to the A. Manzoni Hospital (Lecco, Lombardy Region, Italy) and referred to the UCP-H between 11 March 2020 and 18 April 2020, the period of maximum spread of COVID-19 in this area. Data were collected on the type of hospitalisation, triage process, modality of palliative care and psychological support provided.Results146 COVID-10 patients were referred to the UCP-H. Of these, 120 died during the observation time (82%) while 15 (10.2%) improved and were discharged from the UCP-H care. 93 had less favourable characteristics (rapid deterioration of respiratory function, old age, multiple comorbidities) and an intensive clinical approach was considered contraindicated, while 48 patients had more favourable presentations. Mean follow-up was 4.8 days. A mean of 4.3 assessments per patient were performed. As to respiratory support, 94 patients were treated with oxygen only (at different volumes) and 45 with Continuous Positive Airway Pressure (CPAP).ConclusionThe ongoing pandemic highlighted the need for dedicated palliative care teams and units for dying patients. This work highlights how palliative medicine specialist can make a fundamental contribution thanks to their ability and work experience in an organised multiprofessional context.

Natural pollination of species belonging to the pantropical orchid genusVanillaremains poorly understood. Based on sporadic records, euglossine bees have been observed visiting flowers of NeotropicalVanillaspecies. Our research aimed at better understanding the pollinator attraction mechanism of the Neotropical speciesVanilla pompona, a crop wild relative with valuable traits for vanilla crop improvement programs. Using video footage, we identified floral visitors and examined their behavior. The flowers ofV. pomponaattractedEulaema cingulatamales, which distinctively displayed two behaviors: floral scent collection and nectar search; with the latter leading to pollen removal. Morphological measurements of floral and visitor traits showed that otherEulaemaspecies may also act as potential pollinators. Additionally, we recorded natural fruit set in three populations and over a period of two years, tested for nectar presence and analyzed floral fragrances through gas chromatography - mass spectrometry. We observed a low natural fruit set (2.42%) and did not detect nectar. Twenty floral volatile compounds were identified, with the dominant compound trans-carvone oxide previously found to attractEulaema cingulatamales. We hypothesize a dual attraction ofEulaema cingulatamales toV. pomponaflowers, based on floral fragrance reward as the primary long-distance attraction, and food deception for successful pollen removal. Further research confirming this hypothesis is recommended to develop appropriate conservation policies forVanillacrop wild relatives, which are the primary reserves of this crop’s genetic variation.

The aim of this work is a technical review about Quartz Crystal Microbalance (QCM) sensors used in space missions, i.e. Space Shuttle flights, i.e. NASA Space Transportation System (NASA STS) and satellite missions, that aimed at monitoring the contamination generated by outgassing processes of materials onboard satellites and sensitive payloads. The contamination processes are critical for scientific instrumentation (e.g. optics, telescopes, detectors) because scientific measurements and performances can be jeopardized or worsened by uncontrolled contamination. This issue has been addressed by the space agencies, e.g. NASA, ESA and JAXA that have implemented many different studies to monitor the material outgassing and degradation in space environment. During the past years, the QCM sensors have become the baseline solution for measuring material outgassing and characterizing the on-orbit contamination environment. This work summarizes the main QCM applications in Space and their findings, providing an overview of the sensors’ performances in terms of stability, power, data rate, measurement accuracy and resolution. Different QCM technologies will be compared highlighting the advantages of their use for the next space missions and instrumentations that require an accurate monitoring of contamination environment. In particular, due to more severe contamination requirements for next payloads and instrumentations, QCM sensors would be useful to estimate the cleanliness degree by evaluating the induced contamination and degradation on sensitive instrumentations.

This paper describes a system for the measurement of the internal and external temperature profiles of PET preforms used in the Injection Stretch Blow Moulding (ISBM) process. Many works in literature highlighted the importance of these quantities to improve the production quality of PET bottles, but none addressed the development of a measuring system suitable for this scope. A measuring system based on two thermopiles for the identification of the internal temperature profile and a thermal camera for the measurement of the external one has been designed. The adopted sensors were individually calibrated and the uncertainty budget, accounting for both instrumental uncertainties and the effect of multiple reflections, was derived. A prototype of the measuring system was tested on an industrial ISBM machine. The dependence of the preforms temperature profile on the settings of the ISBM machine was investigated. Results evidenced that the minimum variations of the machine settings induced temperature differences significantly larger than the measurement uncertainty, thus proving the effectiveness of the proposed system.

The future of spaceborne observations is strongly oriented toward miniaturization of payloads without reducing their performances. In this framework telescopes equipped with deployable structures would guarantee either an improvement of the performances or a considerable volume reduction which, due to the limitations on the launcher, translates into a lower cost of in-orbit commissioning. This paper aims at comparing possible mechanism layouts for a deployable space telescope designed for Earth observation in the infrared spectrum. The design considers a classical Cassegrain telescope and aims at packaging the secondary mirror as close as possible to the primary; the trade-off analyses among different technological solutions and configurations are presented. This is a preliminary study performed in the framework of DORA (Deployable Optics for Remote sensing Applications), a project aiming at developing a deployable telescope for minisatellites, and concludes with the assessment of the most feasible layouts which are going to be considered in the next phases of the project.

The Optical Particle Counter 'MicroMED' will be part of the ExoMars 2022 mission and aims to provide the first ever direct measurement of airborne Martian dust. The instrument has been tested at the INAF - OAC premises, where a Martian chamber is present, simulating the Martian environment in terms of pressure, instrument temperature, atmosphere composition and the presence of dust. However, tests in the presence of wind are also needed for the instrument characterization. To this purpose, a test campaign at the AWTS II simulator at the Aarhus University (Denmark) was performed, testing the instrument in the presence of winds up to 15 m/s. Such tests are important since wind is the main agent of landscape modification on Mars. The present work describes the results of such tests, showing the variation of the instrument detecting ability with the wind speed, as well as the influence of temperature on performances.