Experimental investigation of in-plane loaded timber-framed rammed earth panels. Part I: Monotonic shear-compression tests

Rammed earth walls show comparatively good performances with respect to vertical loads, while their stiffness and strength against horizontal loads are often unsatisfactory. Preliminary indications about the timber-framed rammed earth panel (TREP) stiffness and load bearing capacity have been obtained from a first experimental study that has been expressively set up and performed to investigate the TREP in-plane static behavior. The present part I, together with the subsequent part II (companion paper), illustrates and discusses the key experimental results obtained from the compression-shear loading tests performed on rammed earth panels reinforced by a contouring timber frame. In the present part I of the paper, the monotonic loading tests are carefully analyzed, the results are discussed, and the detected damage modes are explained. The results seem to show that the reinforcing timber frame provides a substantial benefit enabling the development of an effective “strut-and-tie” resisting mechanism that effectively exploits the compressive strength of the rammed earth panel and promotes a ductile failure mode

Experimental investigation of in-plane loaded timber-framed rammed earth panels. Part II: cyclic shear-compression tests

Preliminary indications about the timber-framed rammed earth panel (TREP) stiffness and load bearing capacity have been obtained from a first experimental study that has been expressively set up and performed to investigate the TREP in-plane static behavior. The present part II, together with the foregoing part I (companion paper), illustrates and discusses the key experimental results obtained from the compression-shear loading tests performed on rammed earth panels reinforced by a contouring timber frame. In the present part II of the paper, the cyclic loading tests on two TREP elements and one bare timber frame are carefully analyzed, the results are discussed, in terms of load capacity and ductility, and the detected damage modes are explained. The results seem to show that the reinforcing timber frame provides a substantial benefit enabling the development of an effective “strut-and-tie” resisting mechanism that effectively exploits the compressive strength of the rammed earth panel and promotes a ductile failure mode.(undefined

Large-eddy simulation of pyroclastic density currents

We investigate the dynamics of turbulent pyroclastic density currents (PDCs) by adopting a 3D, Eulerian-Eulerian multiphase flow model, in which solid particles are treated as a continuum and the grain-size distribution is simplified by assuming two particulate phases. The turbulent sub-grid stress of the gas phase is modelled within the framework of Large-Eddy Simulation (LES) by means of a eddy-viscosity model together with a wall closure. Despite the significant numerical diffusion associated to the upwind method adopted for the Finite-Volume discretization, numerical simulations demonstrate the need of adopting a Sub-Grid Scale (SGS) model, while revealing the complex interplay between the grid and the SGS filter sizes. We also analyse the relationship between the averaged flow dynamic pressure and the action exerted by the PDC on a cubic obstacle, to evaluate the impact of a PDC on a building. Numerical results suggest that the average flow dynamic pressure can be used as a proxy for the force per unit surface acting on the building envelope (Fig. 5), even for such steeply stratified flows. However, it is not possible to express such roportionality as a constant coefficient such as the drag coefficient in a steady-state current. The present results indeed indicate that the large epistemic and aleatory uncertainty on initial and boundary conditions has an impact on the numerical redictions which is comparable to that of grid resolution

Ultrathin, Ultra‐Conformable, and Free‐Standing Tattooable Organic Light‐Emitting Diodes

A novel tattooable, ultrathin, green organic light‐emitting diode (OLED) fabricated on top of commercial temporary tattoo paper, is demonstrated. The transfer mechanism relies on dissolution of the sacrificial layer typically incorporated in paper‐tattoos. The ready‐to‐use device can be stored on the tattoo substrate and released on the target surface at a later time, simply by a slight wetting of the tattoo paper with water. This approach provides a quick and easy method of transferring OLEDs on virtually any surface. This is particularly appealing, in perspective, for on‐skin and disposable electronic applications. The proof of concept demonstrates, for the very first time, the feasibility of ultrathin operational OLED tattoos. While the performance of such devices is not yet comparable with that of OLEDs on rigid or flexible non‐tattooable substrates, the results show the potential for an OLED tattoo technology in integrated conformable electronic circuits

Adapting Real Quantifier Elimination Methods for Conflict Set Computation

The satisfiability problem in real closed fields is decidable. In the context of satisfiability modulo theories, the problem restricted to conjunctive sets of literals, that is, sets of polynomial constraints, is of particular importance. One of the central problems is the computation of good explanations of the unsatisfiability of such sets, i.e.\ obtaining a small subset of the input constraints whose conjunction is already unsatisfiable. We adapt two commonly used real quantifier elimination methods, cylindrical algebraic decomposition and virtual substitution, to provide such conflict sets and demonstrate the performance of our method in practice

A sub-150-nanometre-thick and ultraconformable solution-processed all-organic transistor

Recent advancements in the field of electronics have paved the way to the development of new applications, such as tattoo electronics, where the employment of ultraconformable devices is required, typically achievable with a significant reduction in their total thickness. Organic materials can be considered enablers, owing to the possibility of depositing films with thicknesses at the nanometric scale, even from solution. However, available processes do not allow obtaining devices with thicknesses below hundreds of nanometres, thus setting a limit. Here, we show an all-organic field effect transistor that is less than 150 nm thick and that is fabricated through a fully solution-based approach. Such unprecedented thickness permits the device to conformally adhere onto nonplanar surfaces, such as human skin, and to be bent to a radius lower than 1 μm, thereby overcoming another limitation for field-effect transistors and representing a fundamental advancement in the field of ultrathin and tattoo electronics

Tear production, intraocular pressure, ultrasound biometric features and conjunctival flora identification in clinically normal eyes of two italian breeds of chicken (Gallus gallus domesticus)

Given the abundance of chickens in Italy, it is important for veterinarians to know the normal state of chickens’ eyes in order to identify any ophthalmic pathological changes. The aim of this study was to determine the normal values of select ocular parameters and to evaluate conjunctival microflora in two Italian chicken breeds. Sixty-six healthy chickens underwent a complete ophthalmic examination, which included a phenol red thread test (PRTT) for the evaluation of tear production and the assessment of intraocular pressure by rebound tonometry. B-mode ultrasound biometric measurements and conjunctival microflora identification were also performed in twenty-seven chickens. Mean PRTT was 23.77 ± 2.99 mm/15 s in the Livorno breed and 19.95 ± 2.81 mm/15 s in the Siciliana breed. Mean intraocular pressure was 14.3 ± 1.17 mmHg in the Livorno breed and 14.06 ± 1.15 mmHg in the Siciliana breed. Reference ranges for morphometric parameters were reported in the two breeds. Twenty-three chickens (85.18%) were bacteriologically positive. Chlamydia spp. antigen was detected in 14.81% of chickens. No positive cultures were obtained for fungi. Normal reference range values for selected ophthalmic parameters were obtained in clinically healthy chickens, which could facilitate accurate diagnosis and better management of ophthalmic diseases in these animals

Serotonin drives striatal synaptic plasticity in a sex-related manner

Introduction: Plasticity at corticostriatal synapses is a key substrate for a variety of brain functions – including motor control, learning and reward processing – and is often disrupted in disease conditions. Despite intense research pointing toward a dynamic interplay between glutamate, dopamine (DA), and serotonin (5-HT) neurotransmission, their precise circuit and synaptic mechanisms regulating their role in striatal plasticity are still unclear. Here, we analyze the role of serotonergic raphe-striatal innervation in the regulation of DA-dependent corticostriatal plasticity. Methods: Mice (males and females, 2–6 months of age) were housed in standard plexiglass cages at constant temperature (22 ± 1 °C) and maintained on a 12/12 h light/dark cycle with food and demineralized water ad libitum. In the present study, we used a knock-in mouse line in which the green fluorescent protein reporter gene (GFP) replaced the I Tph2 exon (Tph2GFP mice), allowing selective expression of GFP in the whole 5-HT system, highlighting both somata and neuritis of serotonergic neurons. Heterozygous, Tph2+/GFP, mice were intercrossed to obtain experimental cohorts, which included Wild-type (Tph2+/+), Heterozygous (Tph2+/GFP), and Mutant serotonin-depleted (Tph2GFP/GFP) animals. Results: Using male and female mice, carrying on different Tph2 gene dosages, we show that Tph2 gene modulation results in sex-specific corticostriatal abnormalities, encompassing the abnormal amplitude of spontaneous glutamatergic transmission and the loss of Long Term Potentiation (LTP) in Tph2GFP/GFP mice of both sexes, while this form of plasticity is normally expressed in control mice (Tph2+/+). Once LTP is induced, only the Tph2+/GFP female mice present a loss of synaptic depotentiation. Conclusion: We showed a relevant role of the interaction between dopaminergic and serotonergic systems in controlling striatal synaptic plasticity. Overall, our data unveil that 5-HT plays a primary role in regulating DA-dependent corticostriatal plasticity in a sex-related manner and propose altered 5-HT levels as a critical determinant of disease-associated plasticity defects

Lower limb deep vein thrombosis in COVID-19 patients admitted to intermediate care respiratory units

COVID-19 has been associated with an increased risk of thrombotic events; however, the reported incidence of deep vein thrombosis varies depending, at least in part, on the severity of the disease. Aim of this prospective, multicenter, observational study was to investigate the incidence of lower limb deep vein thrombosis as assessed by compression ultrasound in consecutive patients admitted to three pulmonary medicine wards designated to care for patients with COVID-19 related pneumonia, with or without respiratory failure but not requiring admission to an intensive care unit. Consecutive patients admitted between March 27 and May 6, 2020 were enrolled. Patients were excluded if they were less than 18-year-old or if compression ultrasound could not be performed for any reason. Patients were assessed at admission (t0) and after 7 days (t1). Major and non-major clinically relevant bleedings were recorded. Sixty-eight patients were enrolled. Two were excluded due to anatomical abnormalities that prevented compression ultrasound; sixty patients were retested at (t1). All patients were started on antithrombotic prophylaxis, unless therapeutic anticoagulation was required. Deep vein thrombosis as assessed by compression ultrasound was observed in 2 patients (3%); one of them was later deemed to represent a previous episode. No new episodes were detected at t1. One major and 2 non-major clinically relevant bleedings were observed. In the setting of patients with COVID-related pneumonia not requiring admission to an intensive care unit, the incidence of deep vein thrombosis is low and our data support not screening asymptomatic patients