11 research outputs found
Modelling of a Hybrid-Electric Light Aircraft
Abstract The European Research and Innovation Agenda as well as the NASA long-term programs have set ambitious targets in terms of emission reduction for the aviation industry. Continuous improvements of conventional technologies will not be enough to fulfil these ambitious requirements; there is a need for revolutionary aircraft concepts and/or radical innovative systems. One such concept is to use a hybrid-electric propulsion system. The CIRA and the Department of Industrial Engineering of the University of Naples "Federico II" have started a joint program in order to develop models and technologies related to the electrification of propulsive system in aviation. The aim of this work is, then, the exploration of possible benefits of hybrid-electric propulsion with a focus on general aviation and selecting appropriate missions. The hybrid-electric system has been designed assembling elements/systems all commercially available, realizing a very simple parallel layout, classifiable as "minimal hybrid". Furthermore, such hybrid-electric system, -inclusive of energy storage system, transmission system, power management system, etc.- has been conceived to fit the original ICE requirements in term of weight, volume and max power at take-off. In this study, a simple model to evaluate the performances of a light aircraft equipped with a hybrid-electric propulsive system has been developed. The approach adopted combine the so-called 0D/1D simulation to evaluate the "single" ICE performances with a simple engineering modeling which allows the performances evaluation of the integrated power plant. The application of model for a simple transfer mission leads to fuel saving up to 20% while for classical training mission, where pilots make numerous run(lap) "touch âand-go", the fuel saving can reach a significative 30%
Improving the quality of patient care in lung cancer: key factors for successful multidisciplinary team working
International Guidelines as well as Cancer Associations recommend a multidisciplinary approach to lung cancer care. A multidisciplinary team (MDT) can significantly improve treatment decision-making and patient coordination by putting different physicians and other health professionals âin the same roomâ, who collectively decide upon the best possible treatment. However, this is not a panacea for cancer treatment. The impact of multidisciplinary care (MDC) on patient outcomes is not univocal, while the effective functioning of the MDT depends on many factors. This review presents the available MDT literature with an emphasis on the key factors that characterize high-quality patient care in lung cancer. The study was conducted with a bibliographic search using different electronic databases (PubMed Central, Scopus, Google Scholar, and Google) referring to multidisciplinary cancer care settings. Many key elements appear consolidated, while others emerge as prevalent and actual, especially those related to visible barriers which work across geographic, organizational, and disciplinary boundaries. MDTs must be sustained by strategic management, structured within the entity, and cannot be managed as a separate care process. Furthermore, they need to coordinate with other teams (within and outside the organization) and join with the broad range of services delivered by multiple providers at various points of the cancer journey or within the system, with the vision of integrated care
Forgetting the Unforgettable: Transient Global Amnesia Part II: A Clinical Road Map
Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of a temporary memory disorder with profound anterograde amnesia and a variable impairment of the past memory. Usually, the attacks are preceded by a precipitating event, last up to 24 h and are not associated with other neurological deficits. Diagnosis can be challenging because the identification of TGA requires the exclusion of some acute amnestic syndromes that occur in emergency situations and share structural or functional alterations of memory circuits. Magnetic Resonance Imaging (MRI) studies performed 24–96 h after symptom onset can help to confirm the diagnosis by identifying lesions in the CA1 field of the hippocampal cornu ammonis, but their practical utility in changing the management of patients is a matter of discussion. In this review, we aim to provide a practical approach to early recognition of this condition in daily practice, highlighting both the lights and the shadows of the diagnostic criteria. For this purpose, we summarize current knowledge about the clinical presentation, diagnostic pathways, differential diagnosis, and the expected long-term outcome of TGA
Forgetting the Unforgettable: Transient Global Amnesia Part I: Pathophysiology and Etiology
Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of a temporary memory disorder with a profound anterograde amnesia and a variable impairment of the past memory. Since the first description, dating back over 60 years, several cases have beenreported in the literature. Nevertheless, TGA remains one of the most mysterious diseases in clinical neurology. The debate regarding the etiology of this disease has focused mainly on three different mechanisms: vascular (due to venous flow changes or focal arterial ischemia), epileptic, and migraine related. However, to date there is no scientific proof of any of these mechanisms. Furthermore, the demonstration by diffusion-weighted MRI of lesions in the CA1 field of the hippocampus cornu ammonis led us to hypothesize that the selective vulnerability of CA1 neurons to metabolic stress could play a role in the pathophysiology of TGA. In this review, we summarize current knowledge on the anatomy, vascularization and function of the hippocampus. Furthermore, we discuss the emerging theories on the etiology and the pathophysiological cascade leading to an impairment of hippocampal function during the attacks
Modelling of a Hybrid-Electric Light Aircraft
The European Research and Innovation Agenda as well as the NASA long-term programs have set ambitious targets in terms of emission reduction for the aviation industry.
Continuous improvements of conventional technologies will not be enough to fulfil these ambitious requirements; there is a need for revolutionary aircraft concepts and/or radical innovative systems. One such concept is to use a hybrid-electric propulsion system.
The CIRA and the Department of Industrial Engineering of the University of Naples âFederico IIâ have started a joint program in order to develop models and technologies related to the electrification of propulsive system in aviation.
The aim of this work is, then, the exploration of possible benefits of hybrid-electric propulsion with a focus on general aviation and selecting appropriate missions.
The hybrid-electric system has been designed assembling elements/systems all commercially available, realizing a very simple parallel layout, classifiable as âminimal hybridâ. Furthermore, such hybrid-electric system, -inclusive of energy storage system, transmission system, power management system, etc.- has been conceived to fit the original ICE requirements in term of weight, volume and max power at take-off.
In this study, a simple model to evaluate the performances of a light aircraft equipped with a hybrid-electric propulsive system has been developed. The approach adopted combine the so-called 0D/1D simulation to evaluate the âsingleâ ICE performances with a simple engineering modeling which allows the performances evaluation of the integrated power plant. The application of model for a simple transfer mission leads to fuel saving up to 20% while for classical training mission, where pilots make numerous run(lap) âtouch âand-goâ , the fuel saving can reach a significative 30%
Modelling of a Hybrid-Electric Light Aircraft
Abstract The European Research and Innovation Agenda as well as the NASA long-term programs have set ambitious targets in terms of emission reduction for the aviation industry. Continuous improvements of conventional technologies will not be enough to fulfil these ambitious requirements; there is a need for revolutionary aircraft concepts and/or radical innovative systems. One such concept is to use a hybrid-electric propulsion system. The CIRA and the Department of Industrial Engineering of the University of Naples "Federico II" have started a joint program in order to develop models and technologies related to the electrification of propulsive system in aviation. The aim of this work is, then, the exploration of possible benefits of hybrid-electric propulsion with a focus on general aviation and selecting appropriate missions. The hybrid-electric system has been designed assembling elements/systems all commercially available, realizing a very simple parallel layout, classifiable as "minimal hybrid". Furthermore, such hybrid-electric system, -inclusive of energy storage system, transmission system, power management system, etc.- has been conceived to fit the original ICE requirements in term of weight, volume and max power at take-off. In this study, a simple model to evaluate the performances of a light aircraft equipped with a hybrid-electric propulsive system has been developed. The approach adopted combine the so-called 0D/1D simulation to evaluate the "single" ICE performances with a simple engineering modeling which allows the performances evaluation of the integrated power plant. The application of model for a simple transfer mission leads to fuel saving up to 20% while for classical training mission, where pilots make numerous run(lap) "touch âand-go", the fuel saving can reach a significative 30%
Mid-term results of endoscopic mitral valve repair and insights in surgical techniques for isolated posterior prolapse
Abstract Background The adoption of minimally invasive techniques to perform mitral valve repair surgery is increasing. This is enhanced by the compelling evidence of satisfactory short-term results and lower major morbidity. We analyzed mid-term follow-up results of our experience, and further compared two techniques: isolated leaflet resection and neochord implantation for posterior leaflet prolapse. Methods Data for all consecutive endoscopic mitral valve repairs via video-assisted right anterior mini-thoracotomy were analyzed between December 2012 and September 2021. The early and mid-term follow-up results were ascertained. The main outcome was the incidence of mortality and the recurrence of significant mitral regurgitation during follow-up which were summarized by the Kaplan-Meier estimator and compared between treatment arms using the stratified log-rank test. Secondary outcomes were the early-postoperative results including 30-days mortality and the occurrence of major complications. Results A total of 309 patients were included. Along with ring annuloplasty, 136 (44.4%) patients received posterior leaflet resection (122 isolated) whereas 97 (31.1%) underwent posterior leaflet chords implantation (88 isolated). Forty-nine patients had annuloplasty alone. In-hospital mortality was 1.0%. Mean follow-up was 28.8â±â22.0 months (maximum 8.3 years). KaplanâMeier survival rate at 5 years was 97.3â±â1.0%, mitral regurgitation ( 3+) or valve reoperation free-survival at 5 years was estimated as 94.5â±â2.3%. Subgroup time-to-event analysis for the indexed outcomes showed no statistical significance between the techniques. Conclusions Endoscopic mitral valve repair is safe and associated with excellent short- and mid-term outcomes. No differences were found between leaflet resection and gore-tex chords implantation for posterior leaflet prolapse
Corpus callosum abnormalities: neuroimaging, cytogenetics and clinical characterization of a very large multicenter Italian series
Corpus callosum abnormalities (CCA) have an estimated prevalence
ranging from 0.3% up to 0.7% in patients undergoing brain imaging.
CCA can be identified incidentally, or can be part of a developmental
disease. We performed a retrospective study of 551 patients, identified
non-syndromic (NS) CCA and syndromic (S) CCA, reviewing clinical features,
neuroradiological aspects, genetic etiology, and chromosomal
microarray (CMA) results. Syndromic CCA subjects were prevalent
(60%) and they showed the most severe clinical features. Cortical malformations
and cerebellar anomalies were 23% of cerebral malformation
associated to CCA (plus), 23 and 14% respectively in syndromic forms. A clinical and/or genetic diagnosis was obtained in 37% of
syndromic CCA including chromosomal rearrangements on high-resolution
karyotype (18%), microdeletion/microduplication syndromes
(31%) and monogenic diseases (51%). Non-syndromic CCA anomalies
had mildest clinical features, although intellectual disability was present
in 49% of cases and epilepsy in 13%. CMA diagnostic rate in our
cohort of patients ranged from 11 to 23% (NS to S). A high percentage
of patients (76% 422/551) remain without a diagnosis. Combined high
resolution CMA studies and next-generation sequencing (NGS) strategies
will increase the probability to identify new causative genes of
CCA and to redefine genotypeâphenotype correlation
Effects of preâoperative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study
We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05-1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4-7 days or >= 8 days of 1.25 (1.04-1.48), p = 0.015 and 1.31 (1.11-1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care