222 research outputs found

    An Approach to Pattern Recognition by Evolutionary Computation

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    Evolutionary Computation has been inspired by the natural phenomena of evolution. It provides a quite general heuristic, exploiting few basic concepts: reproduction of individuals, variation phenomena that affect the likelihood of survival of individuals, inheritance of parents features by offspring. EC has been widely used in the last years to effectively solve hard, non linear and very complex problems. Among the others, EC–based algorithms have also been used to tackle classification problems. Classification is a process according to which an object is attributed to one of a finite set of classes or, in other words, it is recognized as belonging to a set of equal or similar entities, identified by a label. Most likely, the main aspect of classification concerns the generation of prototypes to be used to recognize unknown patterns. The role of prototypes is that of representing patterns belonging to the different classes defined within a given problem. For most of the problems of practical interest, the generation of such prototypes is a very hard problem, since a prototype must be able to represent patterns belonging to the same class, which may be significantly dissimilar each other. They must also be able to discriminate patterns belonging to classes different from the one that they represent. Moreover, a prototype should contain the minimum amount of information required to satisfy the requirements just mentioned. The research presented in this thesis, has led to the definition of an EC–based framework to be used for prototype generation. The defined framework does not provide for the use of any particular kind of prototypes. In fact, it can generate any kind of prototype once an encoding scheme for the used prototypes has been defined. The generality of the framework can be exploited to develop many applications. The framework has been employed to implement two specific applications for prototype generation. The developed applications have been tested on several data sets and the results compared with those obtained by other approaches previously presented in the literature

    an experimental protocol to support cognitive impairment diagnosis by using handwriting analysis

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    Abstract Nowadays diseases involving cognitive impairments affect millions of people worldwide, with Alzheimer's and Parkinson's diseases being the most common ones. Because of the worldwide average lifespan increment, it is expected that their incidence will increase in the next few decades. Among the daily activities, handwriting is one of the first affected by cognitive impairments. For this reasons, researchers have also been investigating the analysis of handwriting alterations as diagnostic signs for this kind of diseases. In this paper we present an experimental protocol that we developed for the analysis of the handwriting dynamics of patients affected by cognitive impairments. The aim of this protocol is to build a large database that would allow to effectively train different classifier systems. We also detail the most common and effective features previously used in the literature to represent handwriting dynamics of the subjects affected by cognitive impairments

    Progetto FADOI “EUCLIDE”. Clinica, comunicazione, telemedicina e governance: le esperienze da COVID-19 per il futuro della Medicina Interna

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    Introduzione Dario Manfellotto, Francesco Dentali, Andrea Fontanella Materiali e Metodi Dario Manfellotto, Francesco Dentali, Andrea Fontanella Gestione clinica del paziente complesso con patologie cardiovascolari e comorbilità Giuseppe Campagna, Claudia Ferrigno, Franco Mastroianni Gestione clinica del paziente complesso con diabete e comorbilità Ada Maffettone, Ernesto De Menis, Maria Serena Fiore Cura e comunicazione: l’esperienza nella pandemia e le prospettive future Luigi Magnani, Lara Bellardita, Salvatore Lenti Gestione a distanza del paziente complesso: la medicina digitale Filippo Pieralli, Flavio Tangianu, Maria Gabriella Coppola Governance per la Medicina Interna Andrea Montagnani, Roberta Re, Ilario Stefani Considerazioni conclusive Dario Manfellotto, Francesco Dentali, Andrea Fontanell

    PapyRow: A Dataset of Row Images from Ancient Greek Papyri for Writers Identification

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    Papyrology is the discipline that studies texts written on ancient papyri. An important problem faced by papyrologists and, in general by paleographers, is to identify the writers, also known as scribes, who contributed to the drawing up of a manuscript. Traditionally, paleographers perform qualitative evaluations to distinguish the writers, and in recent years, these techniques have been combined with computer-based tools to automatically measure quantities such as height and width of letters, distances between characters, inclination angles, number and types of abbreviations, etc. Recently-emerged approaches in digital paleography combine powerful machine learning algorithms with high-quality digital images. Some of these approaches have been used for feature extraction, other to classify writers with machine learning algorithms or deep learning systems. However, traditional techniques require a preliminary feature engineering step that involves an expert in the field. For this reason, publishing a well-labeled dataset is always a challenge and a stimulus for the academic world as researchers can test their methods and then compare their results from the same starting point. In this paper, we propose a new dataset of handwriting on papyri for the task of writer identification. This dataset is derived directly from GRK-Papyri dataset and the samples are obtained with some enhancement image operation. This paper presents not only the details of the dataset but also the operation of resizing, rotation, background smoothing, and rows segmentation in order to overcome the difficulties posed by the image degradation of this dataset. It is prepared and made freely available for non-commercial research along with their confirmed ground-truth information related to the task of writer identification

    Primary Co-Occurrence of Gonadal and Extragonadal Central Nervous System (CNS) Germ Cell Tumors (GCTs): Case Report and Review of the Literature

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    Background: The primary co-occurrence of gonadal and extragonadal central nervous system (CNS) germ cell tumors (GCTs) has rarely been reported in the literature, and a common opinion on the underlying etiopathogenetic mechanism is lacking. Objective: We aim to investigate the pathophysiological mechanisms and genetic pathways underlying the primary co-occurrence of gonadal and CNS GCTs. Methods: We reviewed data from 29 consecutive patients with a diagnosis of CNS GCT, evaluated in our Hospital over the past 23 years, and searched for those who had at least a primary gonadal co-occurrence of GCT. A systematic review of the literature according to the PRISMA guidelines was also conducted. For a comprehensive and detailed search, PubMed, Ovid MEDLINE, and Ovid EMBASE databases have been consulted. Boolean operators and MeSH terms were used to find studies. Only articles published between 2000 and 2023 were considered. Results: Including our Institutional case report, a total of 7 patients with both testicular NGGCTs and CNS GCTs were identified (5 patients with metachronous tumors and patients with synchronous presentation). The average age at tumor diagnosis was 17 years. The cerebral histotypes reported were mixed GCTs (3 cases; 43%), pure germinomas (3 cases, 43%), and one yolk sac tumor (14%). Two out of seven cases (29%) were syndromic, one suffering from Down Syndrome and the other from Testicular Dysgenesis Syndrome. Regarding the etiology and molecular mechanism of GCT development, several gene mutations have been reported in the literature. Particularly, genetic alterations in the MAPK and/or PI3K/AKT/mTOR pathway, together with mutations of the KIT gene, have been shown to guarantee survival and transformation of mismigrated totipotent primordial germ cells, while suppressor genes allow their resistance against apoptotic death. Aberrant chromosomes have also been reported to be responsible for oncogenic transformation. It is also known that CNS and testicular GCTs share some genetic/epigenetic profiles. Conclusions: The primary co-occurrence of testicular NGGCT and extragonadal CNS GCTs is extremely rare. Genetic factors seem to play a paramount role in their etiopathogenesis. Additional research is needed to elucidate molecular mechanisms of oncogenesis in such patients

    Endoscopic evacuation of massive intraventricular hemorrhages reduces shunt dependency: a meta-analysis

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    Intraventricular hemorrhage (IVH) is characterized by severe prognosis. The amount of intraventricular blood is the most important, disease-specific, prognostic factor, as acute complications are strictly dependent on clot formation. Although external ventricular drain (EVD) placement is the standard treatment, in the past 15 years neuroendoscopic (NE) evacuation of IVH has been advocated, but available comparative data are limited. A systematic review of the literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included articles compare the treatment of primary and secondary IVH with NE and EVD. The meta-analysis was performed in terms of shunt dependency. Cochran's Q-test and I2 statistics were used to assess heterogeneity in the studies. No heterogeneity was considered for p greater than 0.05 and I2 less than 20%. A random-effect model was used, with restricted maximum likelihood to estimate the heterogeneity variance. After screening 744 articles, 5 were included in the meta-analysis. A total of 303 patients presenting with primary or pure (50 patients) and secondary (253 patients) IVH, undergoing either NE (151) or EVD (152), were included in the metanalysis. The risk of ventriculoperitoneal (VP) shunt was higher in the EVD group (relative risk: 1.93, 95% confidence interval: 1.28-2.92, p  = 0.0094). The risk of VP shunt was higher in the EVD group, but the overall outcome remains poor for patients with IVH, with a moderate-to-high disability. Large randomized controlled trials are needed to evaluate more deeper both advantages and effects on the outcome of NE over EVD

    Epidemiology-based evaluation of trends in treatment for ruptured intracranial aneurysms in Italy

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    Background: In recent years there have been significant advances in the diagnosis, management and treatment of intracranial aneurysms (IAs) in Italy. Changes in prevalence of several epigenetic risk factors in the population as well as in environmental factors may have influenced the epidemiological burden of this disease. No long-term, population-based study about the incidence of treated ruptured IAs (rIAs) in Italy has yet been reported in literature. Methods: A long-term (January 2015 - December 2020), nationwide epidemiology study was performed by using discharge data collected by the Italian National Agency for Regional Healthcare Services with a particular focus on the treatment incidence of rIAs. A sub-analysis per macro-areas (north, center, and south and islands) was also performed, including the data about regional healthcare systems organization. The prevalence of common epigenetic and environmental risk factors has been also assessed. Results: Over 6 years, the mean incidence of rIAs treatment was 2.7 x 100.000 per year (ds ± 0.1; range: 2.6-2.9). In 2020, there was a significant north-south decreasing gradient in incidence (north vs center vs south and islands: 3.4 vs 2.4 vs 1.8 x 100.000/year; all p<0.001). There were no meaningful differences between macro-areas in terms of access to emergency care and number of neurosurgical wards per population. The rate of unruptured IAs (uIAs) treatment did not show a correlation to that of ruptured ones. Minor regional differences were retrieved for high-risk hypertension as well as for alcohol abuse prevalence. Air pollutants and temperature charts showed a north-south gradient similar to that of the incidence in the treated rIAs. Conclusions: The mean incidence of treated rIAs was stable over the 2015-2020 period in Italy. A north-south decreasing gradient in rIAs treatment incidence was reported. Neither the Regional healthcare organizations nor the rate of uIAs treatment were significant factors explaining the regional differences in the incidence of rIAs treatment. Minor differences in epigenetic and environmental risk factors may be synergistically involved

    Anemia and iron in internal medicine: an Italian survey and a review on iron intravenous therapy in medical patients

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    In Italy, Internal Medicine Units hospitalize approximately 1,300,000 patients, often elderly and comorbid. The prevalent diagnoses are respiratory diseases, heart failure, or pneumonia. As a matter of fact, anemia is probably underestimated in the compilation of the official discharge forms (SDO) according to ICD-9 diagnostic codes. We promoted a survey among the Members the Italian Scientific Society of Internal Medicine (FADOI) with the aim to investigate the prevalence of anemia and iron deficiency, over than certain aspects related to the therapeutic management of patients with anemia. Furthermore, we performed a review summarizing current evidence for iron intravenous therapy in these patients. According to the survey, anemia is present in around half of the patients hospitalized in Internal Medicine, and about a quarter of them shows iron metabolism alterations. In the evaluation of iron metabolism, the dosage of ferritin is the most requested exam, whereas transferrin saturation is less considered. By focusing on some categories of patients, the awareness of the usefulness of intravenous iron therapy in patients with heart failure seems to be sufficiently common (76% of physicians), while it seems lower (60%) in the management of patients with chronic kidney disease (CKD) and anemia. Finally, more than 75% of the physicians answered that, in their hospital, there are few outpatients' offices or diagnostic pathways dedicated to patients with anemia. Anemia due to absolute or functional iron deficiency is particularly prevalent in Internal Medicine inpatients. For this reason, an accurate evaluation of iron profile and an adequate iron therapy is mandatory in these patients. Recent studies show that, in patients with heart failure, intravenous iron therapy is an effective way of improving patients' health, regardless of the presence of anemia. Similarly, iron therapy results fundamental to optimize erythropoiesis-stimulating agent efficacy in patients with chronic renal failure. In the next future, other therapeutic aspects of intravenous iron therapy will be probably clarified by several interesting ongoing studies focused on these patients

    Regional diastolic function by tissue Doppler echocardiography in systemic sclerosis: correlation with clinical variables

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    The incidence of left ventricular (LV) diastolic dysfunction is increased in systemic sclerosis (SSc), while systolic dysfunction is present in a small percentage of patients. The aim of this study was to asses the LV "regional" diastolic abnormalities in SSc patients by the mean of Doppler tissue imaging (DTI). Echocardiographic echo-Doppler (DE) and DTI parameters were analyzed for 67 SSc patients: abnormal E/A ratio at DE was detected in 24, while abnormal e/a at DTI was observed in 41. A significant prevalence of DTI diastolic abnormalities in the segments reflecting longitudinal versus those reflecting radial LV motion was found. The segments of the basal regions of LV myocardium were significantly more involved than those of the middle portion. Linear correlation was observed between the extent of the diastolic abnormalities and the duration of disease. Longitudinal myocardial systolic velocities were significantly reduced in patients with abnormal e/a DTI
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