Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
IEEE Comput Graph Appl ; PP2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-37015597

RESUMO

The Covid-19 pandemic and its dramatic worldwide impact have required global multidisciplinary actions to mitigate its effects. Mobile phone activity-based digital contact tracing (DCT) via Bluetooth Low Energy (BLE) technology has been considered a powerful pandemic monitoring tool, yet it sparked a controversial debate about privacy risks for people. In order to explore the potential benefits of a DCT system in the context of Occupational Risk Prevention, this paper presents the potential of Visual Analytics methods to summarize and extract relevant information from complex DCT data collected during a long-term experiment at our research centre. Visual tools were combined with quantitative metrics to provide insights into contact patterns among volunteers. Results showed that crucial actors such as participants acting as bridges between groups could be easily identified - ultimately allowing for making more informed management decisions aimed at containing the potential spread of a disease.

2.
Sensors (Basel) ; 21(9)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923203

RESUMO

The possibility of measuring in real time the different types of analytes present in food is becoming a requirement in food industry. In this context, biosensors are presented as an alternative to traditional analytical methodologies due to their specificity, high sensitivity and ability to work in real time. It has been observed that the behavior of the analysis curves of the biosensors follow a trend that is reproducible among all the measurements and that is specific to the reaction that occurs in the electrochemical cell and the analyte being analyzed. Kinetic reaction modeling is a widely used method to model processes that occur within the sensors, and this leads to the idea that a mathematical approximation can mimic the electrochemical reaction that takes place while the analysis of the sample is ongoing. For this purpose, a novel mathematical model is proposed to approximate the enzymatic reaction within the biosensor in real time, so the output of the measurement can be estimated in advance. The proposed model is based on adjusting an exponential decay model to the response of the biosensors using a nonlinear least-square method to minimize the error. The obtained results show that our proposed approach is capable of reducing about 40% the required measurement time in the sample analysis phase, while keeping the error rate low enough to meet the accuracy standards of the food industry.


Assuntos
Técnicas Biossensoriais , Cinética , Modelos Teóricos , Oxirredução
3.
Healthc Technol Lett ; 5(5): 167-171, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30464848

RESUMO

StereoElectroEncephaloGraphy (SEEG) is a minimally invasive technique that consists of the insertion of multiple intracranial electrodes to precisely identify the epileptogenic focus. The planning of electrode trajectories is a cumbersome and time-consuming task. Current approaches to support the planning focus on electrode trajectory optimisation based on geometrical constraints but are not helpful to produce an initial electrode set to begin with the planning procedure. In this work, the authors propose a methodology that analyses retrospective planning data and builds a set of average trajectories, representing the practice of a clinical centre, which can be mapped to a new patient to initialise planning procedure. They collected and analysed the data from 75 anonymised patients, obtaining 30 exploratory patterns and 61 mean trajectories in an average brain space. A preliminary validation on a test set showed that they were able to correctly map 90% of those trajectories and, after optimisation, they have comparable or better values than manual trajectories in terms of distance from vessels and insertion angle. Finally, by detecting and analysing similar plans, they were able to identify eight planning strategies, which represent the main tailored sets of trajectories that neurosurgeons used to deal with the different patient cases.

4.
Comput Methods Programs Biomed ; 164: 49-64, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30195431

RESUMO

OBJECTIVES: Hospital readmission risk prediction facilitates the identification of patients potentially at high risk so that resources can be used more efficiently in terms of cost-benefit. In this context, several models for readmission risk prediction have been proposed in recent years. The goal of this review is to give an overview of prediction models for hospital readmission, describe the data analysis methods and algorithms used for building the models, and synthesize their results. METHODS: Studies that reported the predictive performance of a model for hospital readmission risk were included. We defined the scope of the review and accordingly built a search query to select the candidate papers. This query string was used as input for the chosen search engines, namely PubMed and Google Scholar. For each study, we recorded the population, feature selection method, classification algorithm, sample size, readmission threshold, readmission rate and predictive performance of the model. RESULTS: We identified 77 studies that met the inclusion criteria, out of 265 citations. In 68% of the studies (n = 52) logistic regression or other regression techniques were utilized as the main method. Ten (13%) studies used survival analysis for model construction, while 14 (18%) used machine learning techniques for classification, of which decision tree-based methods and SVM were the most utilized algorithms. Among these, only four studies reported the use of any class imbalance addressing technique, of which resampling is the most frequent (75%). The performance of the models varied significantly among studies, with Area Under the ROC Curve (AUC) values in the ranges between 0.54 and 0.92. CONCLUSION: Logistic regression and survival analysis have been traditionally the most widely used techniques for model building. Nevertheless, machine learning techniques are becoming increasingly popular in recent years. Recent comparative studies suggest that machine learning techniques can improve prediction ability over traditional statistical approaches. Regardless, the lack of an appropriate benchmark dataset of hospital readmissions makes a comparison of models' performance across different studies difficult.


Assuntos
Readmissão do Paciente/estatística & dados numéricos , Algoritmos , Área Sob a Curva , Interpretação Estatística de Dados , Mortalidade Hospitalar , Humanos , Modelos Logísticos , Aprendizado de Máquina , Modelos Estatísticos , Fatores de Risco
5.
Stud Health Technol Inform ; 207: 1-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25488205

RESUMO

In this work we present a system that uses the accelerometer embedded in a mobile phone to perform activity recognition, with the purpose of continuously and pervasively monitoring the users' level of physical activity in their everyday life. Several classification algorithms are analysed and their performance measured, based for 6 different activities, namely walking, running, climbing stairs, descending stairs, sitting and standing. Feature selection has also been explored in order to minimize computational load, which is one of the main concerns given the restrictions of smartphones in terms of processor capabilities and specially battery life.


Assuntos
Actigrafia/instrumentação , Telefone Celular/instrumentação , Redes de Comunicação de Computadores/instrumentação , Diagnóstico por Computador/métodos , Monitores de Aptidão Física , Software , Acelerometria/instrumentação , Acelerometria/métodos , Actigrafia/métodos , Adulto , Algoritmos , Fontes de Energia Elétrica , Humanos , Aprendizado de Máquina , Masculino , Reconhecimento Automatizado de Padrão/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Stud Health Technol Inform ; 207: 261-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25488232

RESUMO

This paper describes an innovative architecture for the remote follow-up of the health of chronic patients, and its implementation which is called Hygehos Home. The main purpose of the system is to enhance the quality of the daily healthcare practice, by means of bringing both patient and medical professionals closer to each other and by empowering the patient in the healing process. On the one side, Hygehos Home is a platform which gives the patient access to a set of personalized e-Health services using different channels such as web or smartphone. The e-Health services currently provided are: a) health related questionnaires, b) vital sign delivery (weight, blood pressure, oxygen level in blood, temperature, etc.), c) pharmacologic treatment adherence follow-up, d) access to information about the disease, and e) direct communication with the care providers (physicians, nurses, etc.). On the other side, Hygehos Home is fully integrated in the Hospital Information System (HIS), so that the healthcare professionals can easily access all data registered by the patients, such as subjective feedback, vital signs, medication uptake, etc. In this way, the health professionals are able to conduct an efficient and continuous remote supervision of the evolution of the patient. Finally, the validation protocol being conducted is described.


Assuntos
Assistência ao Convalescente/métodos , Doença Crônica/terapia , Registros Eletrônicos de Saúde , Monitorização Ambulatorial/métodos , Telemedicina/métodos , Humanos , Invenções
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...