Earthquake dynamics constrained from laboratory experiments: new insights from granular materials

The traction evolution is a fundamental ingredient to model the dynamics of an earthquake rupture which ultimately controls, during the coseismic phase, the energy release, the stress redistribution and the consequent excitation of seismic waves. In the present paper we explore the use of the friction behavior derived from laboratory shear experiments performed on granular materials at low normal stress. We find that the rheological properties emerging from these laboratory experiments can not be described in terms of preexisting governing models already presented in literature; our results indicate that neither rate-and state-dependent friction laws nor nonlinear slip-dependent models, commonly adopted for modeling earthquake ruptures, are able to capture all the features of the experimental data. Then, by exploiting a novel numerical approach, we directly incorporate the laboratory data into a code to simulate the fully dynamic propagation of a 3-D slip failure. We demonstrate that the rheology of the granular material, imposed as fault boundary condition, is dynamically consistent. Indeed, it is able to reproduce the basic features of a crustal earthquake, spontaneously accelerating up to some terminal rupture speed, both sub- and supershear

Earthquake dynamics constrained from laboratory experiments: new insights from granular materials

The traction evolution is a fundamental ingredient to model the dynamics of an earthquake rupture which ultimately controls, during the coseismic phase, the energy release, the stress redistribution and the consequent excitation of seismic waves. In the present paper we explore the use of the friction behavior derived from laboratory shear experiments performed on granular materials at low normal stress. We find that the rheological properties emerging from these laboratory experiments can not be described in terms of preexisting governing models already presented in literature; our results indicate that neither rate–and state–dependent friction laws nor nonlinear slip–dependent models, commonly adopted for modeling earthquake ruptures, are able to capture all the features of the experimental data. Then, by exploiting a novel numerical approach, we directly incorporate the laboratory data into a code to simulate the fully dynamic propagation of a 3–D slip failure. We demonstrate that the rheology of the granular material, imposed as fault boundary condition, is dynamically consistent. Indeed, it is able to reproduce the basic features of a crustal earthquake, spontaneously accelerating up to some terminal rupture speed, both sub– and supershear

Toward Future Automatic Warehouses: An Autonomous Depalletizing System Based on Mobile Manipulation and 3D Perception

This paper presents a mobile manipulation platform designed for autonomous depalletizing tasks. The proposed solution integrates machine vision, control and mechanical components to increase flexibility and ease of deployment in industrial environments such as warehouses. A collaborative robot mounted on a mobile base is proposed, equipped with a simple manipulation tool and a 3D in-hand vision system that detects parcel boxes on a pallet, and that pulls them one by one on the mobile base for transportation. The robot setup allows to avoid the cumbersome implementation of pick-and-place operations, since it does not require lifting the boxes. The 3D vision system is used to provide an initial estimation of the pose of the boxes on the top layer of the pallet, and to accurately detect the separation between the boxes for manipulation. Force measurement provided by the robot together with admittance control are exploited to verify the correct execution of the manipulation task. The proposed system was implemented and tested in a simplified laboratory scenario and the results of experimental trials are reported

Sevoflurane vs propofol in high risk cardiac surgery: design of the randomized trial “Sevo-Aifa”

Objective. Recent evidence indicates that volatile anesthetics improve post-ischemic recovery. In a meta-analysis of 22 randomized studies, the use of volatile anesthetics was associated with significant reduction in myocardial infarction and mortality. All the studies in this meta-analysis included low risk patients undergoing isolated procedures (mostly isolated coronary artery bypass grafting). We want to confirm the cardioprotective effects of volatile anesthetics, in cardiac surgery, as indicated by a reduced intensive care unit stay and/or death in a high risk population of patients, undergoing combined valvular and coronary procedures. Methods. Four centres will randomize 200 patients to receive either total intravenous anesthesia with propofol or anesthesia with sevoflurane. All patients will receive a standard average dose of opiates. Perioperative management will be otherwise identical and standardized. Transfer out of the intensive care unit will follow standard criteria. Results. Reduced cardiac damage will probably translate into better tissue perfusion and faster recovery, as documented by a reduced intensive care unit stay. The study is powered to detect a reduction in the composite end point of prolonged intensive care unit stay (>2days) and/or death from 60% to 40%. Conclusions. This will be the first multicentre randomized controlled trial comparing the effects of volatile anesthetics and total intravenous anesthesia in high risk patients undergoing cardiac procedures. Our trial should help clarify whether or not volatile agents should be recommended in high risk patients undergoing cardiac surgery

Streptococcus agalactiae clones infecting humans were selected and fixed through the extensive use of tetracycline

Streptococcus agalactiae (Group B Streptococcus, GBS) is a commensal of the digestive and genitourinary tracts of humans that emerged as the leading cause of bacterial neonatal infections in Europe and North America during the 1960s. Due to the lack of epidemiological and genomic data, the reasons for this emergence are unknown. Here we show by comparative genome analysis and phylogenetic reconstruction of 229 isolates that the rise of human GBS infections corresponds to the selection and worldwide dissemination of only a few clones. The parallel expansion of the clones is preceded by the insertion of integrative and conjugative elements conferring tetracycline resistance (TcR). Thus, we propose that the use of tetracycline from 1948 onwards led in humans to the complete replacement of a diverse GBS population by only few TcR clones particularly well adapted to their host, causing the observed emergence of GBS diseases in neonates. \ua9 2014 Macmillan Publishers Limited. All rights reserved

Continuous vs Intermittent Meropenem Administration in Critically Ill Patients With Sepsis

Importance: Meropenem is a widely prescribed β-lactam antibiotic. Meropenem exhibits maximum pharmacodynamic efficacy when given by continuous infusion to deliver constant drug levels above the minimal inhibitory concentration. Compared with intermittent administration, continuous administration of meropenem may improve clinical outcomes. Objective: To determine whether continuous administration of meropenem reduces a composite of mortality and emergence of pandrug-resistant or extensively drug-resistant bacteria compared with intermittent administration in critically ill patients with sepsis. Design, setting, and participants: A double-blind, randomized clinical trial enrolling critically ill patients with sepsis or septic shock who had been prescribed meropenem by their treating clinicians at 31 intensive care units of 26 hospitals in 4 countries (Croatia, Italy, Kazakhstan, and Russia). Patients were enrolled between June 5, 2018, and August 9, 2022, and the final 90-day follow-up was completed in November 2022. Interventions: Patients were randomized to receive an equal dose of the antibiotic meropenem by either continuous administration (n = 303) or intermittent administration (n = 304). Main outcomes and measures: The primary outcome was a composite of all-cause mortality and emergence of pandrug-resistant or extensively drug-resistant bacteria at day 28. There were 4 secondary outcomes, including days alive and free from antibiotics at day 28, days alive and free from the intensive care unit at day 28, and all-cause mortality at day 90. Seizures, allergic reactions, and mortality were recorded as adverse events. Results: All 607 patients (mean age, 64 [SD, 15] years; 203 were women [33%]) were included in the measurement of the 28-day primary outcome and completed the 90-day mortality follow-up. The majority (369 patients, 61%) had septic shock. The median time from hospital admission to randomization was 9 days (IQR, 3-17 days) and the median duration of meropenem therapy was 11 days (IQR, 6-17 days). Only 1 crossover event was recorded. The primary outcome occurred in 142 patients (47%) in the continuous administration group and in 149 patients (49%) in the intermittent administration group (relative risk, 0.96 [95% CI, 0.81-1.13], P = .60). Of the 4 secondary outcomes, none was statistically significant. No adverse events of seizures or allergic reactions related to the study drug were reported. At 90 days, mortality was 42% both in the continuous administration group (127 of 303 patients) and in the intermittent administration group (127 of 304 patients). Conclusions and relevance: In critically ill patients with sepsis, compared with intermittent administration, the continuous administration of meropenem did not improve the composite outcome of mortality and emergence of pandrug-resistant or extensively drug-resistant bacteria at day 28. Trial registration: ClinicalTrials.gov Identifier: NCT03452839

How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Progettazione di un Sistema Mobile di Manipolazione Robotizzata per il progetto COORSA

La robotica mobile è un settore industriale multidisciplinare in continuo sviluppo che coinvolge differenti aree di studio ingegneristiche, quali meccanica, elettronica, informatica e intelligenza artificiale. I robot mobili, comunemente costituiti da un braccio robotico seriale e da una base mobile controllabile, sono sistemi meccatronici in grado di muoversi e svolgere autonomamente compiti assegnati. Sebbene questa branca della robotica si trovi ancora ad uno stadio di sviluppo preliminare, numerosi prototipi e prodotti in serie costituiscono una realtà già consolidata da diversi anni nei settori più disparati della logistica industriale. L'ambito della robotica seriale, invece, si sta dirigendo sempre più verso i robot collaborativi, particolare variante dei robot tradizionali che, grazie all'integrazione di sensori ed algoritmi di controllo sofisticati, permettono la collaborazione uomo-macchina, senza arrecare danno alla salute dell'operatore umano. In tale settore applicativo si inserisce il progetto COORSA (COllaborazione tra Operatori e Robot manipolatori mobili Sicuri per la fAbbrica del futuro) mirando allo studio, e al successivo sviluppo, di un prototipo di robotica mobile adatto ad operazioni industriali nell'ambito di packaging e handling, integrando in sicurezza il lavoro di operatori umani con robot collaborativi. In questa Tesi di Laurea Magistrale si sviluppa un modello di robot mobile in grado di operare in ambienti industriali, quali magazzini e depositi logistici. Al robot è richiesto di eseguire un'operazione di pick and place, basato sul prelevamento del prodotto da un pallet sorgente e successivo deposito in un pallet di destinazione