Congenital hearing loss in Malta : a survey

The congenitally deaf infant who acquires deafness prior to development of language present special problems when compared to other hearing impaired individuals. This is because both the development of speech and of language depends on adequate hearing. As speech and language are our prime means of communication, the congenitally deaf child is automatically also handicapped in his psychological development, social adaptation and work adaptability. The authors reviewed cases of congenital hearing loss presenting on a 20 year period to establish the incidence of congenital hearing impairment in the Maltese islands; to determine the common causes; to highlight any difficulties in early diagnosis and management of these children.peer-reviewe

Cytomegalovirus Management in Solid Organ Transplant Recipients: A Pre-COVID-19 Survey From the Working Group of the European Society for Organ Transplantation

Infections are leading causes of morbidity/mortality following solid organ transplantation (SOT) and cytomegalovirus (CMV) is among the most frequent pathogens, causing a considerable threat to SOT recipients. A survey was conducted 19 July–31 October 2019 to capture clinical practices about CMV in SOT recipients (e.g., how practices aligned with guidelines, how adequately treatments met patients’ needs, and respondents’ expectations for future developments). Transplant professionals completed a ∼30-minute online questionnaire: 224 responses were included, representing 160 hospitals and 197 SOT programs (41 countries; 167[83%] European programs). Findings revealed a heterogenous approach to CMV diagnosis and management and, sometimes, significant divergence from international guidelines. Valganciclovir prophylaxis (of variable duration) was administered by 201/224 (90%) respondents in D+/R− SOT and by 40% in R+ cases, with pre-emptive strategies generally reserved for R+ cases: DNA thresholds to initiate treatment ranged across 10–10,000 copies/ml. Ganciclovir-resistant CMV strains were still perceived as major challenges, and tailored treatment was one of the most important unmet needs for CMV management. These findings may help to design studies to evaluate safety and efficacy of new strategies to prevent CMV disease in SOT recipients, and target specific educational activities to harmonize CMV management in this challenging population

Highly efficient planar perovskite solar cells through band alignment engineering

The simplification of perovskite solar cells (PSCs), by replacing the mesoporous electron selective layer (ESL) with a planar one, is advantageous for large-scale manufacturing. PSCs with a planar TiO2 ESL have been demonstrated, but these exhibit unstabilized power conversion efficiencies (PCEs). Herein we show that planar PSCs using TiO2 are inherently limited due to conduction band misalignment and demonstrate, with a variety of characterization techniques, for the first time that SnO2 achieves a barrier-free energetic configuration, obtaining almost hysteresis-free PCEs of over 18% with record high voltages of up to 1.19 V

Coherent Population Trapping with Controlled Interparticle Interactions

We investigate Coherent Population Trapping in a strongly interacting ultracold Rydberg gas. Despite the strong van der Waals interactions and interparticle correlations, we observe the persistence of a resonance with subnatural linewidth at the single-particle resonance frequency as we tune the interaction strength. This narrow resonance cannot be understood within a meanfield description of the strong Rydberg--Rydberg interactions. Instead, a many-body density matrix approach, accounting for the dynamics of interparticle correlations, is shown to reproduce the observed spectral features

Clathrin mediates both internalization and vesicular release of triggered T cell receptor at the immunological synapse

Ligation of T cell receptor (TCR) to peptide-MHC (pMHC) complexes initiates signaling leading to T cell activation and TCR ubiquitination. Ubiquitinated TCR is then either internalized by the T cell or released toward the antigen-presenting cell (APC) in extracellular vesicles. How these distinct fates are orchestrated is unknown. Here, we show that clathrin is first recruited to TCR microclusters by HRS and STAM2 to initiate release of TCR in extracellular vesicles through clathrin- and ESCRT-mediated ectocytosis directly from the plasma membrane. Subsequently, EPN1 recruits clathrin to remaining TCR microclusters to enable trans-endocytosis of pMHC-TCR conjugates from the APC. With these results, we demonstrate how clathrin governs bidirectional membrane exchange at the immunological synapse through two topologically opposite processes coordinated by the sequential recruitment of ecto- and endocytic adaptors. This provides a scaffold for direct two-way communication between T cells and APCs

Numerical Investigation of the Size Effects on the Creep Damage Coupling

AbstractThe service-life of concrete structures depends on the delayed strains that appear due to creep phenomenon. Few are the studies that treated the effect of the dimensions of concrete specimens on the amplitude and the kinetics of creep and the results show many contradictions. Thus, to design reliable civil engineering structures, the knowledge of the behaviour of concrete under a sustained load including size effect is necessary and performing calculations are needed. In this paper, the physical mechanisms behind the size effect on creep rate are evaluated at the mesoscopic scale. The material volume is modeled, by a Digital Concrete model which takes into account the microstructure heterogeneities and the “real” aggregate size of concrete. Calculations are performed in 2D by considering a viscoelastic damage behaviour law for the matrix and an elastic behavior for aggregates. The numerical results show that size effect is well reproduced by the meso-scale approach. The stresses under a sustained load are induced by strain incompatibilities between the components at the mesoscale. Accordingly, the evolution of the microcracked zone with the size of the bending specimens can be related to the creep rate