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Turbulent phenomena are among the most striking effects that both classical and quantum fluids can exhibit. While classical turbulence is ubiquitous in nature, the observation of quantum turbulence requires the precise manipulation of quantum fluids such as superfluid helium or atomic Bose-Einstein condensates. In this work we demonstrate the turbulent dynamics of a 2D quantum fluid of exciton-polaritons, hybrid light-matter quasiparticles, both by measuring the kinetic energy spectrum and showing the onset of vortex clustering. We demonstrate that the formation of clusters of quantum vortices is triggered by the increase of the incompressible kinetic energy per vortex, showing the tendency of the vortex-gas towards highly excited configurations despite the dissipative nature of our system. These results lay the basis for the investigations of quantum turbulence in two-dimensional fluids of light.

A corrugated Dion–Jacobson 2D perovskite has been integrated with a 3D MAPbBr3 perovskite by using a blend and bilayer approach for application in light emitting diodes.

Optical bound states in the continuum (BIC) are peculiar topological states that, when realized in a planar photonic crystal lattice, are symmetry-protected from radiating in the far field despite lying within the light cone, i.e., in the energy-momentum dispersion region for which radiation can propagate out of the lattice plane. These BICs possess an invariant topological charge given by the winding number of the polarization vectors, similarly to vortices in quantum fluids, such as superfluid helium and atomic Bose-Einstein condensates. In spite of several reports of optical BICs in patterned dielectric slabs with evidence of lasing, their potential as topologically protected states with theoretically infinite lifetime has not been fully exploited, yet. Here we show Bose-Einstein condensation of polaritons, hybrid light-matter excitations, occuring in a BIC thanks to its peculiar non-radiative nature. The combination of the ultra-long BIC lifetime and the tight confinement of the waveguide geometry allow to achieve an extremely low threshold density for condensation, which is not reached in the dispersion minimum but at a saddle point in reciprocal space. By bridging bosonic condensation and symmetry-protected radiation eigenmodes, we unveil new ways of imparting topological properties onto macroscopic quantum states with unexplored dispersion features. Such an observation may open a route towards energy-efficient polariton condensation in cost-effective integrated devices, ultimately suited for the development of hybrid light-matter optical circuits

The homeostatic control of their environment is an essential task of living cells. It has been hypothesized that when microenvironmental pH inhomogeneities are induced by high cellular metabolic activity, diffusing protons act as signaling molecules, driving the establishment of cross-feeding networks sustained by the cell-to-cell shuttling of overflow products such as lactate. Despite their fundamental role, the extent and dynamics of such networks is largely unknown due to the lack of methods in single cell flux analysis. In this study we provide direct experimental characterization of such exchange networks. We devise a method to quantify single cell fermentation fluxes over time by integrating high-resolution pH microenvironment sensing via ratiometric nanofibers with constraint-based inverse modeling. We apply our method to cell cultures with mixed populations of cancer cells and fibroblasts. We find that the proton trafficking underlying bulk acidification is strongly heterogeneous, with maximal single cell fluxes exceeding typical values by up to 3 orders of magnitude. In addition, a crossover in time from a networked phase sustained by densely connected “hubs” (corresponding to cells with high activity) to a sparse phase dominated by isolated dipolar motifs (i.e. by pair-wise cell-to-cell exchanges) is uncovered, which parallels the time course of bulk acidification. Our method promises to shed light on issues ranging from the homeostatic function of proton exchange to the metabolic coupling of cells with different energetic demands, and paves the way for real-time non-invasive single cell metabolic flux analysis.

By modifying the size and shape of the molecules, we managed to tune the hole mobility of our HTMs up to three orders of magnitude. Our best HTM led to a solar cell lifetime that is tripled compared to that based on spiro-OMeTAD.

Background Lacosamide (LCM) is a third-generation anti-seizure medication (ASM) approved for focal onset epilepsy in patients aged ≥4 years. Previous studies have reported an efficacy of LCM as add-on treatment in brain tumour-related epilepsy (BTRE). To date, there are no studies in the literature focusing on lacosamide used in monotherapy to treat BTRE. In our retrospective study we investigated efficacy and tolerability of LCM in monotherapy in a multicentre national cohort of primary brain tumour patients. Patients and Methods Adult patients who were treated with LCM in monotherapy were collected from 12 Italian Centres (either mainly involved in neuro-oncology or in epileptology). Main inclusion criteria were diagnosis of primary brain tumour; at least two focal-onset seizures in the disease course; LCM used either as primary or secondary monotherapy after withdrawal of previous ASMs. For each patient, we evaluated seizure freedom at 3 and 6 months (primary endpoints), side effects and drop-out rate (secondary endpoints). Results We collected 132 patients. The majority of patients had a diagnosis of diffuse gliomas, being those with lower-grade glioma 66 (50.0%) and those with glioblastoma 33 (25.0%). Overall, LCM led to seizure-freedom in 64.4% of patients at 3 months and 55% at 6 months. Patients who used two or more ASMs before LCM had a worse seizure control than patients in monotherapy with LCM as first choice.In 14 patients, we observed seizure control despite tumour progression on magnetic resonance (MRI). Multivariate analysis showed that gross-total resection at diagnosis and use of steroids were significantly associated with higher seizure freedom rate at 6 months. Side effects were mainly mild (grade 1-2 according to the CTCAE classification), and the drop-out rate was low (1.5%). The main side effects were dizziness and somnolence. Conclusion This is the first study on the role of LCM in monotherapy in BTRE. The study has shown a good efficacy and tolerability of LCM with more than a half of patients becoming seizure-free at 6 months and with a very low rate of drop-out. Further studies are needed to confirm these preliminary data in a prospective manner, adding quality of life and neurocognitive functions as endpoints.

Bound states in the continuum (BICs)

© 1963-2012 IEEE. The CMS Collaboration has been developing large-area triple-gas electron multiplier (GEM) detectors to be installed in the muon Endcap regions of the CMS experiment in 2019 to maintain forward muon trigger and tracking performance at the High-Luminosity upgrade of the Large Hadron Collider (LHC); 10 preproduction detectors were built at CERN to commission the first assembly line and the quality controls (QCs). These were installed in the CMS detector in early 2017 and participated in the 2017 LHC run. The collaboration has prepared several additional assembly and QC lines for distributed mass production of 160 GEM detectors at various sites worldwide. In 2017, these additional production sites have optimized construction techniques and QC procedures and validated them against common specifications by constructing additional preproduction detectors. Using the specific experience from one production site as an example, we discuss how the QCs make use of independent hardware and trained personnel to ensure fast and reliable production. Preliminary results on the construction status of CMS GEM detectors are presented with details of the assembly sites involvement. ispartof: IEEE Transactions On Nuclear Science vol:65 issue:11 pages:2808-2816 status: published

The authors reply to the comment by R. P. Steer discussing the reasons for their incorrect assignment of the luminescence decay of the novel compound 5,10,15-(triphenyl),20-[ethynyl-(4-carboxy)phenyl]tetrabenzoporphyrinate Zn(ii) (PETBP). Further DFT and TDDFT calculations have been performed on the compound to investigate the possibility of a direct S

The incidence of circulating colony-forming cells (CFU-C) and the ability of peripheral leucocytes to stimulate the colony formation (CSA) have been studied through a double layer agar culture system in 26 patients with neutrophilic leucocytosis and compared to the values obtained in 26 normal subjects. Both mean CFU-C incidence and mean leucocyte CSA of the whole group of patients were found significantly higher than normal, but considerable variation was observed among singular patients. The different patterns of blood CFU-C and leucocyte CSA are discussed. The combined evaluation of blood CFU-C and leucocyte CSA is found a useful tool to investigate the pathogenetic mechanisms of neutrophilic leucocytosis.

On 10 March 2010, due to the heavy rainfall that occurred on the previous days, the Montaguto earthflow reactivated, involving the road SS 90 "Delle Puglie", as had happened previously in May 2005 and in September 2009, and reaching the Roma–Bari railway. This determined a special attention of the National Civil Protection Department and a widespread monitoring and analysis program was initiated. A monitoring activity using GB-InSAR (Ground Based Interferometric Synthetic Aperture Radar) system began, in order to investigate the landslide kinematics, to plan urgent safety measures for risk mitigation and to design long term stabilization work. In this paper the GB-InSAR monitoring system results and its applications in the Observational Method (OM) approach are presented. The paper also highlights how the OM based on the GB-InSAR technique can produce savings in cost and time on engineering projects, without compromising safety, and how it can also benefit the geotechnical community by increasing scientific knowledge. This study focuses on the very much active role played by the monitoring activities, in both the design and plan modifications; with a special consideration for the emergency phase.

The ability to create photoanodes in which the structural and morphological features of the underlying TiO2 nanocrystalline constituents provide a tailored nanotexture with a higher degree of functionality still represents an indispensible step toward boosting the ultimate light-to electricity conversion of photoelectrochemical devices. This is especially evident for dye solar cells. In this paper we have systematically analyzed the impact of several different TiO2 nanorod morphologies on the most meaningful electrochemical features of the mesoporous photoelectrode of a dye solar cell. The most relevant findings have been then adopted as design criteria to realize an optimized multilayered photoelectrode with a properly engineered architecture which embodies three different breeds of nanocrystal with synergistic peculiarities. It exhibited superior power conversion efficiencies with respect to conventional nanoparticle-based reference film.

The absorption properties of pi-extended macrocycles such as porphyrins and phthalocyanines have been intensively applied to the light -harvesting process related to organic photovoltaics, with particular focus on polymer cells and Dye-Sensitized Solar Cells. In the last few years a large amount of new phthalocyanines have been synthesized and studied and amongst them an interesting sterically hindered push-pull structure, having a record efficiency value of 6.4% has been prepared and published. Even if porphyrins have obtained higher values in terms of efficiency, having the most efficient ones recently shown an impressive efficiency value of 12%, thus comparable to that of N719, the outstanding stability and high molar extinction coefficients (e> 10E5) of phthalocyanines make them very attractive sensitizers with possible applications in Graetzel cells and justify the intensive study carried on these molecules. It is well known that the metal centers of these macrocyclic compounds can affect their absorption peaks, their HOMO/LUMO energy values as well as their possible charge transfer properties in a DSSC device. Thus our goal was to investigate the performances of dyes possessing the same molecular structure having different central metal ions, in order to understand how their harvesting capabilities could be influenced by this kind of substitution. In particular we have chosen an unsymmetric tri-ter-butyl phthalocyanine bearing an ethynylbenzoic unit as anchoring group to the TiO2, that have been synthesized and fully characterized by our research group some years ago as zinc complex. In the present contribution, the synthesis of different 9(10),16(17),23(24)-tri-ter-butyl-2-[acetynyl-(4-carboxy)phenyl]phthalocyaninato metal complexes and their optical, chemical and electrochemical characterizations will be presented. The related free-base phthalocyanine will also be analyzed. Theoretical calculations of both frontier molecular orbitals and simulated absorption spectra with the preliminary measurements of the related DSSCs, where obtained, will be also discussed.

Exciton-polaritons are bosonic quasiparticles that arise from the normal mode splitting of photons in a microcavity and excitons in a semiconductor material. One of the most intriguing extensions of such a lightmatter interaction is the so-called ultrastrong coupling regime. It is achieved when the Rabi frequency (Omega(R), the energy exchange rate between the emitter and the resonant photonic mode) reaches a considerable fraction of the emitter transition frequency, omega(0). Here, we report a Rabi energy splitting (2h Omega(R)) of 1.12 eV and record values of the coupling ratio (2 Omega(R)/omega(0)) up to 0.6-fold the material band gap in organic semiconductor microcavities and up to 0.5-fold in monolithic heterostructure organic light-emitting diodes working at room temperature. Furthermore, we show that with such a large coupling strength it is possible to undress the exciton homogeneous linewidth from its inhomogeneous broadening, which allows for an unprecedented narrow emission line (below the cavity finesse) for such organic LEDs. The latter can be exploited for the realization of novel monochromatic sources and near-IR organic emitting devices

The absorption properties of p-extended macrocycles such as porphyrins and phthalocyanines have been intensively applied to the light -harvesting process related to organic photovoltaics, with particular focus on polymer cells and Dye-Sensitized Solar Cells1. In the last few years a large amount of new porphyrins2 have been synthesized and studied and amongst them an interesting push-pull structure, having an impressive efficiency value of 12%, thus comparable to that of N719, has been obtained and published3. Even if phthalocyanines have obtained lower values in terms of efficiency, having the most efficient ones recently exceeded 6%4, their outstanding stability and high molar extinction coefficients (e> 105) make them very attractive sensitizers with possible applications in Graetzel cells and justify the intensive study carried on these molecules. Our goal was to investigate the performances of macrocyclic-like compounds having a structure that could potentially combine the best features of both the molecules described above. Benzoporphyrins, never investigated as chromophores in DSSC devices, show an intense absorption in the visible and rear-IR regions of the solar spectrum which can be modulated by an accurate tailoring of their structure. These structures can possibly be substituted on the free meso and b-positions, allowing the formation of push-pull systems that can affect the frontier orbitals of the systems to promote and favour the electron injection into the TiO2 surface. Moreover, the insertion of bulky electron-donating groups on the periphery of the macrocycle could suppress or at least diminish those aggregation phenomena which can lower down the efficiency of the correspondent solar cells. In the present contribution, the multistep synthesis of triphenyltetrabenzoporphyrin TP1 and its optical, chemical and electrochemical characterizations will be presented. Theoretical calculations of both frontier molecular orbitals and simulated absorption spectra with the preliminary measurements of the related DSSCs will be also discussed.

Exciton–polaritons in semiconductors are quasi-particles which have recently shown the capability to undergo phase transition into a coherent hybrid state of light and matter. The observation of such quasi-particles in organic microcavities has attracted increasing attention for their characteristic of reaching condensation at room temperature. In this work, the emission properties of organic polaritons are demonstrated not to depend on the overlap between the absorption and emission states of the molecule and that the emission dynamics are modifi ed in the strong coupling regime, showing a signifi cant enhancement of the photoluminescence intensity as compared to the bare dye. This paves the way to the investigation of molecules with large absorption coeffi cients but poor emission effi ciencies for the realization of polariton condensates and organic electrically injected lasers by exploiting strong exciton-photon coupling regimes.

The coupling of the electromagnetic field with an electronic transition gives rise, for strong enough light-matter interactions, to hybrid states called exciton-polaritons. When the energy exchanged between light and matter becomes a significant fraction of the material transition energy an extreme optical regime called ultrastrong coupling (USC) is achieved. We report a microcavity embedded p-i-n monolithic organic light emitting diode working in USC, employing a thin film of squaraine dye as active layer. A normalized coupling ratio of 30% has been achieved at room temperature. These USC devices exhibit a dispersion-less angle-resolved electroluminescence that can be exploited for the realization of innovative optoelectronic devices. Our results may open the way towards electrically pumped polariton lasers.

Photoreflectance spectroscopy (PR) of In 0.1 Ga 0.9 As GaAs and Al0.3Ga0.7 As/GaAs near-surface quantum wells has been investigated to determine the influence of the quantum well on the surface potential. In the regime of carriers tunneling from the quantum well to surface states, the PR signal from the well decreases, until vanishing when tunneling dominates over radiative recombination in the well. This result suggests that a quantum well next to the surface has the effect of creating a nearly flat band condition in a region comprehensive of the surface and the well itself.

The recent work of the authors' group in the field of KEMS studies of intermetallic gaseous molecules is reviewed. Examples are given of systems such as intragroup 14 diatomic molecules, -tri- and tetratomic species in the Si- Sn systems, and diatomic species containing Group 11 elements. Special attention is given to species containing heavy metals, where relativistic effects can play an important role in the stabilization or destabilization of the chemical bond. The results of the ab initio investigation of the same species at various levels of theory, up to CCSD(T), are also reported, showing the importance of combining the experimental and theoretical study of intermetallic molecules.

A method for the mass spectrometric quantitative determination, down to the sub-ppb level, of the 4 He content in the gaseous products of cold fusion Pd+D 2 O electrolytic cells is described. The data collected in an experiment lasting over 1000 h provided a time picture of the phenomena. Measurements of the 20 Ne content have also been performed in order to check air contamination. The methods and controls employed are suitable for use with non-dedicated mass spectrometers which cannot be operated in vacuum static conditions.

The germanium monochalcogenide molecules Ge2S2, Ge2Se2, and Ge2Te2 were identified in a Knudsen cell mass spectrometric study of the vapors in equilibrium over solid GeS, GeSe, and GeTe. From a second and third law evaluation of the equilibrium data the following dimerization energies ΔH0,dimo were determined: 106.5 ± 2.1, 102.1 ± 4.6, 102 ± 8 kJ mol−1 for Ge2S2, Ge2Se2, Ge2Te2, respectively. These data and literature data allow to look into trends of the bonding energetics of group IVB-VIB gaseous compounds.