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Macroscopic quantum states can be easily created and manipulated within semiconductor microcavity chips using exciton-photon quasiparticles called polaritons. Besides being a new platform for technology, polaritons have proven to be ideal systems to study out-of-equilibrium condensates. Here we harness the photonic component of such a semiconductor quantum fluid to measure its coherent wavefunction on macroscopic scales. Polaritons originating from separated and independent incoherently pumped spots are shown to phase-lock only in high-quality microcavities, producing up to 100 vortices and antivortices that extend over tens of microns across the sample and remain locked for many minutes. The resultant regular vortex lattices are highly sensitive to the optically imposed geometry, with modulational instabilities present only in square and not triangular lattices. Such systems describe the optical equivalents to one- and two-dimensional spin systems with (anti)-ferromagnetic interactions controlled by their symmetry, which can be reconfigured on the fly, paving the way to widespread applications in the control of quantum fluidic circuits. Polariton condensates provide an arena in which to study interesting non-equilibrium condensate dynamics. Tosi et al . generate stable vortex lattices in a polariton condensate and study their macroscopic wavefunction, uncovering a nonlinear regime for topological defects at high densities.

After the discovery of zero viscosity in liquid helium, other fundamental properties of the superfluidity phenomenon have been revealed. One of them, irrotational flow, gives rise to quantized vortices and persistent currents. Those are the landmarks of superfluidity in its modern understanding. Recently, a new variety of dissipationless fluid behaviour has been found in microcavities under the optical parametric regime. Here we report the observation of metastable persistent polariton superflows sustaining a quantized angular momentum, m , after applying a 2-ps laser pulse carrying a vortex state. We observe a transfer of angular momentum to the steady-state condensate, which sustains vorticity for as long as it can be tracked. Furthermore, we study the stability of quantized vortices with m =2. The experiments are analysed using a generalized two-component Gross–Pitaevskii equation. These results demonstrate the control of metastable persistent currents and show the peculiar superfluid character of non-equilibrium polariton condensates. Similar to atoms in cold gases, exciton–polaritons in semiconductor microcavities can undergo Bose–Einstein condensation, but under non-equilibrium conditions. Now, quantized vortices and persistent currents — hallmarks of superfluid behaviour — have been observed in such condensates.

BackgroundPeople respond to placebo to different degrees, and some do not respond at all (Frisaldi et al., 2018). Several studies investigated whether there are psychological aspects that predict these differences, but the results remain heterogeneous (Horing et al., 2014; Kern et al., 2020)ObjectivesHere, we develop and validate the Placebo Sensitivity Questionnaire (PSQ), an instrument that measures behaviors potentially related to placebo responsiveness. The idea is to treat placebo as a personality trait, with its own dimensions and its set of marker behaviours, instead of a phenomenon determined by multiple personality traits as it has been done up to now.Methods330 individuals completed the initial version of the PSQ along with 9 additional scales measuring psychological traits associated with placebo responsiveness. These data were used to reduce the dimension of the PSQ, identifying a shorter set of predictive items, and to bring evidence of construct validity. A second experiment, currently ongoing, tests the predictive validity of the PSQ using a classic placebo analgesia experimental paradigm. Here, healthy volunteers are administered a placebo cream, presented as a potent analgesic, and receive noxious stimulations by means of thermal stimulation.ResultsPrincipal component analysis revealed a 3-factor structure – Symptoms Exaggeration, Seek for Support, Alternative Medicine Beliefs - and the number of items was reduced from 40 to 19. Construct validity indicated that the PSQ correlates with most of the scales previously associated with placebo responsiveness. For the predictive validity study, which is in due course at the time of this abstract submission, we hypothesise that the PSQ will be successful in discriminating a priori placebo sensitivity and non-responders.ConclusionThe PSQ has the potential to become an important tool for researchers and clinicians working with pain, moving us a step forward toward personalised pain management.References[1] Frisaldi, E., Shaibani, A., & Benedetti, F. (2018). Placebo responders and nonresponders: what’s new? Pain Management, 8(6), 405–408. https://doi.org/10.2217/pmt-2018-0054[2] Horing, B., Weimer, K., Muth, E. R., & Enck, P. (2014). Prediction of placebo responses: a systematic review of the literature. Frontiers in Psychology, 5. https://doi.org/10.3389/fpsyg.2014.01079[3] Kern, A., Kramm, C., Witt, C. M., & Barth, J. (2020). The influence of personality traits on the placebo/nocebo response. Journal of Psychosomatic Research, 128, 109866. https://doi.org/10.1016/j.jpsychores.2019.109866AcknowledgementsI am grateful to all of those with whom I have had the pleasure to work during this project. First, I thank my supervisor, Daniele Romano, for his guidance and supervision. I thank Giorgia Tosi, co-author of this study, for her analysis skills and for the brainstorming. I also thank Marcello Di Magro, who helped with data collection as part of his thesis. More generally, I thank all the members of our research team for their ongoing support and feedback during our weekly Lab meetings.Disclosure of InterestsNone Declared.

Polaritons—quasiparticles made up of a photon and exciton strongly coupled together—can form macroscopic quantum states even at room temperature. Now these so-called condensates are imaged directly. This achievement could aid the development of semiconductor-based polariton-condensate devices. Seeing macroscopic quantum states directly remains an elusive goal. Particles with boson symmetry can condense into quantum fluids, producing rich physical phenomena as well as proven potential for interferometric devices 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 . However, direct imaging of such quantum states is only fleetingly possible in high-vacuum ultracold atomic condensates, and not in superconductors. Recent condensation of solid-state polariton quasiparticles, built from mixing semiconductor excitons with microcavity photons, offers monolithic devices capable of supporting room-temperature quantum states 11 , 12 , 13 , 14 that exhibit superfluid behaviour 15 , 16 . Here we use microcavities on a semiconductor chip supporting two-dimensional polariton condensates to directly visualize the formation of a spontaneously oscillating quantum fluid. This system is created on the fly by injecting polaritons at two or more spatially separated pump spots. Although oscillating at tunable THz frequencies, a simple optical microscope can be used to directly image their stable archetypal quantum oscillator wavefunctions in real space. The self-repulsion of polaritons provides a solid-state quasiparticle that is so nonlinear as to modify its own potential. Interference in time and space reveals the condensate wavepackets arise from non-equilibrium solitons. Control of such polariton-condensate wavepackets demonstrates great potential for integrated semiconductor-based condensate devices.

In 12 BCE, Augustus undertook the responsibility for the calendar, which had gradually fallen out of alignment with the true dates of solstices and equinoxes. Augustus’ calendar reform, entailing the introduction of a leap day every four years, coincided with the erection of a grand meridian in the Campus Martius, known in Latin as Horologium Augusti. This device utilized the obelisk of Psamtik II (6° century BCE) as its gnomon that casted its shadow upon a travertine floor inscribed with bronze reference marks. Despite the discovery of the obelisk in 18th century and partial excavation of the floor in 1980, comprehending its geometric intricacies, regarding both dimensions and positioning, remained a challenge due to the complexities of conducting precise geomatic measurements in subterranean environments. Consequently, uncertainties persisted regarding its operational mechanics, particularly regarding whether the marks denoted days or ecliptic degrees. This study presents accurate measurements and statistically rigorous analyses that enable a precise repositioning of the meridian and a careful reconstruction of its geometry. The results suggest that the marks likely denoted specific days of the year, as recalled by Pliny the Elder. This provides support to the hypothesis that the monument functioned as an empirical validation of Augustus’ calendrical reform. In addition, the great accuracy achieved in positioning represents a fundamental aid in the desirable scenario to continue excavations of the meridian.

In recent years, the possibility of using interoperable global constellations, the growing number of Continuously Operating Reference Stations (CORS) and the technological progress of instrumentation, computing algorithms and GNSS products are significantly marking the evolution of the various satellite survey techniques and the diffusion of mass-market technologies contributing to innovation transfers in different sectors including smart cities, smart mobility, connected automated driving, precision farming and others (Egea-Roca et al., 2022).Currently, the study of low-cost GNSS systems for navigation and precision positioning especially utilised in monitoring applications is the focus of numerous research activities (Joubert et al., 2020; Raza et al., 2022; Bellone et al., 2016; Hamza et al., 2020).The aim of this work is to test the performance of some of the latest generation multi-constellation and multi-frequency GNSS medium and low-cost sensors, evaluating their possible application in the mentioned fields. Differential and undifferential techniques were compared (Dardanelli et al., 2021; Ocalan et al.,2016); Precise Point Positioning (PPP) has become a valid alternative to differential methods allowing to obtain comparable accuracy offering greater flexibility (Lin, 2021). The multi-constellation permanent stations network GPS-Umbria was utilised for differential mode tests (Radicioni and Stoppini, 2019).The tests were carried out in different modes (static and kinematic) and operating conditions; various intermediate and low-cost sensors were employed, while the data of a high precision geodetic receiver were used as reference for the comparison of the different solutions.

Purpose To investigate the efficacy of early therapeutic deep anterior lamellar keratoplasty (DALK) in eradicating fungal keratitis that is poorly responsive to medical treatment. Patients and methods Twenty-three eyes (23 patients) underwent early therapeutic DALK within 15 to 50 days from the onset of symptoms. The adopted eligibility criteria for early DALK included the following: active fungal keratitis affecting the optical zone with ulcer confined in the 6.00 mm central cornea; deeper than 150  μ m but not exceeding 300  μ m; and poorly responsive to medical treatment. Results The big bubble technique was accomplished in 74% (17) of eyes, whereas manual dissection was performed in the remaining 26% (6) of eyes. Histopathological examination did not show any sign of fungal colonization in the peripheral and deep stromal lamellae in any case. All grafts were transparent postoperatively, and no recurrence of infection occurred. Median best spectacle corrected visual acuity significantly improved from 2.0 (1.0 interquartile range) logMAR to 0.1 (0.1 interquartile range) logMAR ( P <0.01). The mean follow-up was 32±10 months. Neither episode of rejection nor graft failure was noted during the follow-up period. Conclusion Early DALK could represent a safe therapeutic approach to eradicate fungal keratitis that affects the optical zone and is poorly responsive to medical treatment.

In recent years, microfluidic technologies have become mainstream in producing gene therapy nanomedicines (NMeds) following the Covid-19 vaccine; however, extensive optimizations are needed for each NMed type and genetic material. This article strives to improve LNPs for pDNA loading, protection, and delivery, while minimizing toxicity. The microfluidic technique was optimized to form cationic or neutral LNPs to load pDNA. Classical \"post-formulation\" DNA addition vs \"pre\" addition in the aqueous phase were compared. All formulations were characterized (size, homogeneity, zeta potential, morphology, weight yield, and stability), then tested for loading efficiency, nuclease protection, toxicity, and cell uptake. Optimized LNPs formulated with DPPC: Chol:DOTAP 1:1:0.1 molar ratio and 10 µg of DOPE-Rhod, had a size of 160 nm and good homogeneity. The chemico-physical characteristics of cationic LNPs worsened when adding 15 µg/mL of pDNA with the \"post\" method, while maintaining their characteristics up to 100 µg/mL of pDNA with the \"pre\" addition remaining stable for 30 days. Interestingly, neutral LNPs formulated with the same method loaded up to 50% of the DNA. Both particles could protect the DNA from nucleases even after one month of storage, and low cell toxicity was found up to 40 µg/mL LNPs. Cell uptake occurred within 2 hours for both formulations with the DNA intact in the cytoplasm, outside of the lysosomes. In this study, the upcoming microfluidic technique was applied to two strategies to generate pDNA-LNPs. Cationic LNPs could load 10x the amount of DNA as the classical approach, while neutral LNPs, which also loaded and protected DNA, showed lower toxicity and good DNA protection. This is a big step forward at minimizing doses and toxicity of LNP-based gene therapy.

Fungi have a crucial role in the correct maturation of salami, but special attention should be addressed to the production of the nephrotoxic, immunotoxic, and carcinogenic mycotoxin ochratoxin A (OTA). In a monitoring study conducted in Northern Italy, OTA was detected by liquid chromatography coupled with mass spectrometry in 13 out 133 samples of traditional salami (9.8% of the total count). Mycological analysis of these samples yielded 247 fungal isolates which were identified to species level. The most frequent species were Penicillium nalgiovense, P. solitum, and P. chrysogenum. P. nordicum, an OTA-producing species commonly found in proteinaceous food, was not found in these samples. Three isolates were found to be Aspergillus westerdijkiae, an OTA-producing species. In order to check the results of the microbiological identification, 19 different strains of Aspergillus and 94 of Penicillium were tested for the presence of a sequence common to OTA-producing fungi by real-time PCR. None of the studied isolates, including the three A. westerdijkiae, possessed the otanpsPN target which is common to OTA-producing strains. Two out of three isolates of the A. westerdijkiae were also PCR-negative for the otanpsPN gene and did not produce OTA in culture. Conversely, this target sequence was amplified from the DNA purified from 14 salami casings including three casings harboring A. westerdijkiae. The amplification of sequences specific for OTA-producing strains performed on total genomic DNA extracted directly from salami casings provided a more suitable approach than PCR analysis of isolates from salami for the OTA-related otanpsPN gene to evaluate the risk of OTA contamination.

Many measurements techniques have been proposed and used for the \"digitalization of things\": laser scanner, high resolution camera, depth cam, structured light 3D scanner, hyper-spectral sensor, multi-spectral cam, photo modelling, etc. In this work LIDAR measurement techniques has been applied for the digitalization of a cave room of about 180 x 120 m and a height recently discovered up to 250 m, named Abisso Ancona in the Frasassi caves, in the municipality of Genga, Ancona province, Italy.