Retrospective epidemiological review on L. pneumophyla

During the first annual control on hospital infections, was observed a curious but explainable trend regarding evidence of Legionella pneumophyla isolated by water systems in numerous public and private nosocomial structures. After first massive isolation of L. pneumophyla strains at the beginning, a considerable reduction of isolates was noted, due to a program based on control and surveillance of water supplies, with regards to the aspectatives. But, in these last years a recurrent presence of isolates of L. pneumophyla was noted, despite all procedures used for the control of these bacteria

Tetrapod-shaped colloidal nanocrystals of II-VI semiconductors prepared by seeded growth.

We report a general synthetic approach to tetrapod-shaped colloidal nanocrystals made of various combinations of II-VI semiconductors. Uniform tetrapods were prepared using preformed seeds in the sphalerite structure, onto which arms were grown by coinjection of the seeds and chemical precursors into a hot mixture of surfactants. By this approach, a wide variety of core materials could be chosen (in practice, most of the II-VI semiconductors that could be prepared in the sphalerite phase, namely, CdSe, ZnTe, CdTe); in contrast, the best materials for arm growth were CdS and CdTe. The samples were extensively characterized with the aid of several techniques

Temperature and Size Dependence of the Optical Properties of Tetrapod-Shaped Colloidal Nanocrystals Exhibiting Type-II Transitions

We have investigated the optical properties of colloidal seed-grown CdSe (seed)/CdTe (arms) nanotetrapods both experimentally and computationally. The tetrapods exhibit a type-II transition arising from electrons localized in the CdSe seed region and holes delocalized in the CdTe arms, along with a residual type-I recombination in long-arm tetrapods. Experiments and theory helped to identify the origin of both types of transitions and their size dependence. In particular, time-resolved experiments performed at 10 K evidenced a size-dependent, long living type-II radiative emission arising from the peculiar electron–hole wave function localization. Temperature-dependent photoluminescence (PL) studies indicate that, at high temperature (>150 K), the main process limiting the PL quantum efficiency of the type-I PL is thermal escape of the charge carriers through efficient exciton-optical phonon coupling. The type-II PL instead is limited both by thermal escape and by the promotion of electrons from the condu..

Symptoms and feelings valued by patients after a percutaneous coronary intervention: A discrete-choice experiment to inform development of a new patient-reported outcome

Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. Objective To inform the development of a patient-reported outcome measure, the aim of this study was to identify which symptoms and feelings following percutaneous coronary intervention (PCI) are most important to patients. Design Discrete-choice experiment consisting of two hypothetical scenarios of 10 symptoms and feelings (pain or discomfort; shortness of breath; concern/worry about heart problems; tiredness; confidence to do usual activities; ability to do usual activities; happiness; sleep disturbance; dizziness or light-headedness and bruising) experienced after PCI, described by three levels (never, some of the time, most of the time). Preference weights were estimated using a conditional logit model. Setting Four Australian public hospitals that contribute to the Victorian Cardiac Outcomes Registry (VCOR) and a private insurer's claim database. Participants 138 people aged >18 years who had undergone a PCI in the previous 6 months. Main outcome measures Patient preferences via trade-offs between 10 feelings and symptoms. Results Of the 138 individuals recruited, 129 (93%) completed all 16 choice sets. Conditional logit parameter estimates were mostly monotonic (eg, moving to worse levels for each individual symptom and feeling made the option less attractive). When comparing the magnitude of the coefficients (based on the coefficient of the worst level relative to best level in each item), feeling unhappy was the symptom or feeling that most influenced perception of a least-preferred PCI outcome (OR 0.42, 95% CI 0.34 to 0.51, p<0.0001) and the least influential was bruising (OR 0.81, 95% CI 0.67 to 0.99, p=0.04). Conclusion This study provides new insights into how patients value symptoms and feelings they experience following a PCI

Postremission sequential monitoring of minimal residual disease by WT1 Q-PCR and multiparametric flow cytometry assessment predicts relapse and may help to address risk-adapted therapy in acute myeloid leukemia patients

Risk stratification in acute myeloid leukemia (AML) patients using prognostic parameters at diagnosis is effective, but may be significantly improved by the use of on treatment parameters which better define the actual sensitivity to therapy in the single patient. Minimal residual disease (MRD) monitoring has been demonstrated crucial for the identification of AML patients at high risk of relapse, but the best method and timing of MRD detection are still discussed. Thus, we retrospectively analyzed 104 newly diagnosed AML patients, consecutively treated and monitored by quantitative polymerase chain reactions (Q-PCR) on WT1 and by multiparametric flow cytometry (MFC) on leukemia-associated immunophenotypes (LAIPs) at baseline, after induction, after 1st consolidation and after 1st intensification. By multivariate analysis, the factors independently associated with adverse relapse-free survival (RFS) were: bone marrow (BM)-WT1 ≥ 121/10(4) ABL copies (P = 0.02) and LAIP ≥ 0.2% (P = 0.0001) (after 1st consolidation) (RFS at the median follow up of 12.5 months: 51% vs. 82% [P < 0.0001] and 57% vs. 81%, respectively [P = 0.0003]) and PB-WT1 ≥ 16/10(4) ABL copies (P = 0.0001) (after 1st intensification) (RFS 43% vs. 95% [P < 0.0001]) Our data confirm the benefits of sequential MRD monitoring with both Q-PCR and MFC. If confirmed by further prospective trials, they may significantly improve the possibility of a risk-adapted, postinduction therapy of AML

A chemical survey of exoplanets with ARIEL

Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file