10 research outputs found
Resource Saving via Ensemble Techniques for Quantum Neural Networks
Quantum neural networks hold significant promise for numerous applications,
particularly as they can be executed on the current generation of quantum
hardware. However, due to limited qubits or hardware noise, conducting
large-scale experiments often requires significant resources. Moreover, the
output of the model is susceptible to corruption by quantum hardware noise. To
address this issue, we propose the use of ensemble techniques, which involve
constructing a single machine learning model based on multiple instances of
quantum neural networks. In particular, we implement bagging and AdaBoost
techniques, with different data loading configurations, and evaluate their
performance on both synthetic and real-world classification and regression
tasks. To assess the potential performance improvement under different
environments, we conduct experiments on both simulated, noiseless software and
IBM superconducting-based QPUs, suggesting these techniques can mitigate the
quantum hardware noise. Additionally, we quantify the amount of resources saved
using these ensemble techniques. Our findings indicate that these methods
enable the construction of large, powerful models even on relatively small
quantum devices.Comment: Extended paper of the work presented at QTML 2022. Close to published
versio
Fatality rate and predictors of mortality in an Italian cohort of hospitalized COVID-19 patients
Clinical features and natural history of coronavirus disease 2019 (COVID-19) differ widely among different countries and during different phases of the pandemia. Here, we aimed to evaluate the case fatality rate (CFR) and to identify predictors of mortality in a cohort of COVID-19 patients admitted to three hospitals of Northern Italy between March 1 and April 28, 2020. All these patients had a confirmed diagnosis of SARS-CoV-2 infection by molecular methods. During the study period 504/1697 patients died; thus, overall CFR was 29.7%. We looked for predictors of mortality in a subgroup of 486 patients (239 males, 59%; median age 71 years) for whom sufficient clinical data were available at data cut-off. Among the demographic and clinical variables considered, age, a diagnosis of cancer, obesity and current smoking independently predicted mortality. When laboratory data were added to the model in a further subgroup of patients, age, the diagnosis of cancer, and the baseline PaO2/FiO2 ratio were identified as independent predictors of mortality. In conclusion, the CFR of hospitalized patients in Northern Italy during the ascending phase of the COVID-19 pandemic approached 30%. The identification of mortality predictors might contribute to better stratification of individual patient risk
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The Use-Life of Ancestors: Neolithic Cranial Retention, Caching and Disposal at Masseria Candelaro, Apulia, Italy
When archaeologists discuss ‘ancestor cults’ or ‘ancestor veneration’, what this might entail in practice usually remains vague, leading to charges that the concept of ‘ancestors’ is often applied generically. In this article, the authors combine bioarchaeological, taphonomic, radiocarbon, and isotopic studies to explore the ritual practice of the selective retention, curation, and deposition of a group of human crania and mandibles. Between 5500–5400 BC, Neolithic people at Masseria Candelaro (Puglia, Italy) deposited broken crania and mandibles from about fifteen individuals in a heap in the centre of the village. These individuals were mostly probable males, collected over the course of two centuries and actively used, with their deposition marking the final disposal of a ritual collection. The motivations for the curation of cranial bone are investigated through comparison with archaeological and ethnographic examples, advancing an interpretation of ritual practice directed towards ancestors.This work was supported by the European Union through the European Research Council Advanced Grant ‘Making Ancestors: The Politics of Death in European Prehistory’, no. 885137
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Histotaphonomic analysis of bone bioerosion reveals a regional framework of diverse deathways in the Neolithic of Southeast Italy
The wide diversity of Neolithic funerary practices is increasingly recognised. In Southeast Italy, recent studies have drawn attention to the co-existence of multiple ways of treating the dead within single sites and across the region. In this study, we address how such diverse deathways form a regional framework of ritual practice through histotaphonomic analysis of bone bioerosion. Samples were obtained from articulated, semi-articulated and disarticulated remains from four sites in Apulia which each presented different modes of treatment and disposal of the dead. Bone thin sections were analysed by light microscopy to characterise microstructural preservation through features including bacterial bioerosion, staining, inclusions, and Wedl tunnelling. We investigate the early post-mortem histories of individuals whose remains ended up in various states of dis/articulation and diverse depositional contexts. Disarticulated remains frequently displayed arrested or extensive bacterial bioerosion, which was also found in articulated and semi-articulated skeletons. Additionally, remains deposited in similar contexts, as well as articulated and disarticulated remains deposited together in the same context, often showed different histotaphonomic characteristics, suggesting diverse early post-mortem trajectories. As a result, we argue that Neolithic deathways in southeastern Italy incorporated a high level of diversity in the early post-mortem treatment of the body. A framework for funerary practices emerges, whereby disarticulated remains probably originated from bodies which had been buried previously and subjected to varying extents of shelter, exposure to invertebrates, and duration of burial. However, we acknowledge the ongoing research into the origins of bacterial bioerosion and the problem of equifinality, which leaves open the possibility for further scenarios of early post-mortem treatment
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Histotaphonomic analysis of bone bioerosion reveals a regional framework of diverse deathways in the Neolithic of Southeast Italy
Acknowledgements: JET would like to thank Dr. Petros Chatzimpaloglou, Dr. Michael Lewis, and Gian Battista Marras for the production of thin sections and assistance with microscopic analysis, and Biancamaria Bonucci and Martina Farese for assistance with R. We thank Prof. Cecilia Conati Barbaro for useful advice on the Masseria Candelaro material. The authors are grateful to the Soprintendenza Archeologia, Belle Arti e Paessagio (SABAP) per la Città Metropolitana di Bari for permission to analyse the Titolo remains, and SABAP per le Province di Barletta-Andria-Trani e Foggia for permission to analyse the Masseria Candelaro, Grotta Scaloria and Passo di Corvo remains. We are grateful to Francesco Sanseverino, Giuseppe Carbonara, Barbara De Liso and Francesca Frascolla for allowing us to use their illustrations from the Titolo excavations, which were carried out in collaboration with Michele Sicolo. We also wish to thank Dr. Francesca Candilio and Dr. Alessandra Sperduti from the Servizio di Bioarcheologia of the Museo delle Civiltà (Italian Ministry for Culture) for providing access to the Masseria Candelaro collection. We are particularly grateful to Dr. Donatella Pian for providing useful information on the Grotta Scaloria material.The wide diversity of Neolithic funerary practices is increasingly recognised. In Southeast Italy, recent studies have drawn attention to the co-existence of multiple ways of treating the dead within single sites and across the region. In this study, we address how such diverse deathways form a regional framework of ritual practice through histotaphonomic analysis of bone bioerosion. Samples were obtained from articulated, semi-articulated and disarticulated remains from four sites in Apulia which each presented different modes of treatment and disposal of the dead. Bone thin sections were analysed by light microscopy to characterise microstructural preservation through features including bacterial bioerosion, staining, inclusions, and Wedl tunnelling. We investigate the early post-mortem histories of individuals whose remains ended up in various states of dis/articulation and diverse depositional contexts. Disarticulated remains frequently displayed arrested or extensive bacterial bioerosion, which was also found in articulated and semi-articulated skeletons. Additionally, remains deposited in similar contexts, as well as articulated and disarticulated remains deposited together in the same context, often showed different histotaphonomic characteristics, suggesting diverse early post-mortem trajectories. As a result, we argue that Neolithic deathways in southeastern Italy incorporated a high level of diversity in the early post-mortem treatment of the body. A framework for funerary practices emerges, whereby disarticulated remains probably originated from bodies which had been buried previously and subjected to varying extents of shelter, exposure to invertebrates, and duration of burial. However, we acknowledge the ongoing research into the origins of bacterial bioerosion and the problem of equifinality, which leaves open the possibility for further scenarios of early post-mortem treatment.</jats:p
How different countries respond to adverse events whilst patients’ rights are protected
Patient safety is high on the policy agenda internationally. Learning from safety incidents is a core component in achieving the important goal of increasing patient safety. This study explores the legal frameworks in the countries to promote reporting, disclosure, and supporting healthcare professionals (HCPs) involved in safety incidents. A cross-sectional online survey was conducted to ascertain an overview of the legal frameworks at national level, as well as relevant policies. ERNST (The European Researchers' Network Working on Second Victims) group peer-reviewed data collected from countries was performed to validate information. Information from 27 countries was collected and analyzed, giving a response rate of 60%. A reporting system for patient safety incidents was in place in 85.2% (N = 23) of countries surveyed, though few (37%, N = 10) were focused on systems-learning. In about half of the countries (48.1%, N = 13) open disclosure depends on the initiative of HCPs. The tort liability system was common in most countries. No-fault compensation schemes and alternative forms of redress were less common. Support for HCPs involved in patient safety incidents was extremely limited, with just 11.1% (N = 3) of participating countries reporting that supports were available in all healthcare institutions. Despite progress in the patient safety movement worldwide, the findings suggest that there are considerable differences in the approach to the reporting and disclosure of patient safety incidents. Additionally, models of compensation vary limiting patients' access to redress. Finally, the results highlight the need for comprehensive support for HCPs involved in safety incidents
the ERNST study
The COVID-19 pandemic led to the implementation of interventions to provide emotional and psychological support to healthcare workers in many countries. This ecological study aims to describe the strategies implemented in different countries to support healthcare professionals during the outbreak. Data were collected through an online survey about the measures to address the impact of the pandemic on the mental health of healthcare workers. Healthcare professionals, researchers, and academics were invited to respond to the survey. Fifty-six professionals from 35 countries contributed data to this study. Ten countries (28.6%) reported that they did not launch any national interventions. Both developed and developing countries launched similar initiatives. There was no relationship between the existence of any type of initiative in a country with the incidence, lethality, and mortality rates of the country due to COVID-19, and per capita income in 2020. The 24 h hotline for psychological support was the most frequent intervention. Tools for self-rescue by using apps or websites were extensively used, too. Other common interventions were the development of action protocols, availability of regular and updated information, implantation of distance learning systems, early detection of infection programs for professionals, economic reinforcements, hiring of staff reinforcement, and modification of leave and vacation dates.publishersversionpublishe
Simple Parameters from Complete Blood Count Predict In-Hospital Mortality in COVID-19
Introduction. The clinical course of Coronavirus Disease 2019 (COVID-19) is highly heterogenous, ranging from asymptomatic to fatal forms. The identification of clinical and laboratory predictors of poor prognosis may assist clinicians in monitoring strategies and therapeutic decisions. Materials and Methods. In this study, we retrospectively assessed the prognostic value of a simple tool, the complete blood count, on a cohort of 664 patients (F 260; 39%, median age 70 (56-81) years) hospitalized for COVID-19 in Northern Italy. We collected demographic data along with complete blood cell count; moreover, the outcome of the hospital in-stay was recorded. Results. At data cut-off, 221/664 patients (33.3%) had died and 453/664 (66.7%) had been discharged. Red cell distribution width (RDW) (χ2 10.4; p4.68 was characterized by an odds ratio for in-hospital mortality OR=3.40 (2.40-4.82), while the OR for a RDW>13.7% was 4.09 (2.87-5.83); a platelet count>166,000/μL was, conversely, protective (OR: 0.45 (0.32-0.63)). Conclusion. Our findings arise the opportunity of stratifying COVID-19 severity according to simple lab parameters, which may drive clinical decisions about monitoring and treatment
Search for a heavy composite Majorana neutrino in events with dilepton signatures from proton-proton collisions at <math altimg="si1.svg"><msqrt><mrow><mi>s</mi></mrow></msqrt><mo linebreak="goodbreak" linebreakstyle="after">=</mo><mn>13</mn><mtext> TeV</mtext></math>
International audienceResults are presented of a search for a heavy Majorana neutrino Image 1 decaying into two same-flavor leptons ℓ (electrons or muons) and a quark-pair jet. A model is considered in which the Image 1 is an excited neutrino in a compositeness scenario. The analysis is performed using a sample of proton-proton collisions at s=13TeV recorded by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 138fb−1. The data are found to be in agreement with the standard model prediction. For the process in which the Image 1 is produced in association with a lepton, followed by the decay of the Image 1 to a same-flavor lepton and a quark pair, an upper limit at 95% confidence level on the product of the cross section and branching fraction is obtained as a function of the Image 1 mass Image 2 and the compositeness scale Λ. For this model the data exclude the existence of Image 3 (Image 4) for Image 2 below 6.0 (6.1) TeV, at the limit where Image 2 is equal to Λ. For Image 5, values of Λ less than 20 (23) TeV are excluded. These results represent a considerable improvement in sensitivity, covering a larger parameter space than previous searches in Image 6 collisions at 13 TeV