Search results for "population-based"
showing 10 items of 85 documents
Structural bias in population-based algorithms
2014
Abstract Challenging optimisation problems are abundant in all areas of science and industry. Since the 1950s, scientists have responded to this by developing ever-diversifying families of ‘black box’ optimisation algorithms. The latter are designed to be able to address any optimisation problem, requiring only that the quality of any candidate solution can be calculated via a ‘fitness function’ specific to the problem. For such algorithms to be successful, at least three properties are required: (i) an effective informed sampling strategy, that guides the generation of new candidates on the basis of the fitnesses and locations of previously visited candidates; (ii) mechanisms to ensure eff…
An integrated fuzzy cells-classifier
2007
This paper introduces a genetic algorithm able to combine different classifiers based on different distance functions. The use of a genetic algorithm is motivated by the fact that the combination phase is based on the optimization of a vote strategy. The method has been applied to the classification of four types of biological cells, results show an improvement of the recognition rate using the genetic algorithm combination strategy compared with the recognition rate of each single classifier.
Migraine, Cognitive Decline, and Dementia in Older Adults: A Population-Based Study
2022
Background: The potential impact of migraine on cognitive aging among older adults remains controversial. Objective: To examine the relationship of migraine and subtypes with cognitive decline and dementia in an older Swedish population. Methods: This population-based study included 3,069 participants (age ≥ 60 years) from the Swedish National study on Aging and Care in Kungsholmen, Stockholm. Baseline examination was conducted in 2001–2004, and participants were followed every 3 or 6 years until 2013–2016. Data were collected through face-to-face interviews, clinical examinations, laboratory tests, and linkage with registers. Global cognitive function was measured with the Mini-Mental Stat…
Life-Space Mobility and Active Aging as Factors Underlying Quality of Life Among Older People Before and During COVID-19 Lockdown in Finland—A Longit…
2020
Abstract Background Social distancing, that is, avoiding places with other people and staying at home, was recommended to prevent viral transmission during the COVID-19 pandemic. Potentially, reduced out-of-home mobility and lower activity levels among older people may lower their quality of life (QOL). We studied cross-sectional and longitudinal associations of and changes in life-space mobility, active aging, and QOL during COVID-19 social distancing compared to 2 years before. Methods Altogether 809 community-living participants initially aged 75, 80, or 85 years of our active aging study (AGNES) conducted in 2017–2018 took part in the current AGNES-COVID-19 survey in May and June 2020. …
A population-based survey of cognitive performance in a Sicilian elderly community.
2010
<i>Background:</i> The global burden of neurodegenerative diseases is increasing. Previous studies reported differences related to age, gender and socioeconomic status. We calculated the cognitive performances of a Sicilian population aged 65 years or older, by means of a door-to-door population-based survey in Bagheria city, Sicily. <i>Methods:</i> A door-to-door survey was carried out in the city of Bagheria, Sicily (prevalence day September 30, 2006). A cohort of 2,200 persons was randomly stratified, obtaining a 25% sample of the whole population. Cognitive function was assessed by Mini Mental State Examination (MMSE). Percentile distributions by age, gender, edu…
Incremental Gaussian Discriminant Analysis based on Graybill and Deal weighted combination of estimators for brain tumour diagnosis
2011
In the last decade, machine learning (ML) techniques have been used for developing classifiers for automatic brain tumour diagnosis. However, the development of these ML models rely on a unique training set and learning stops once this set has been processed. Training these classifiers requires a representative amount of data, but the gathering, preprocess, and validation of samples is expensive and time-consuming. Therefore, for a classical, non-incremental approach to ML, it is necessary to wait long enough to collect all the required data. In contrast, an incremental learning approach may allow us to build an initial classifier with a smaller number of samples and update it incrementally…
Major Congenital Anomalies in Babies Born With Down Syndrome
2014
Previous studies have shown that over 40% of babies with Down syndrome have a major cardiac anomaly and are more likely to have other major congenital anomalies. Since 2000, many countries in Europe have introduced national antenatal screening programs for Down syndrome. This study aimed to determine if the introduction of these screening programs and the subsequent termination of prenatally detected pregnancies were associated with any decline in the prevalence of additional anomalies in babies born with Down syndrome. The study sample consisted of 7,044 live births and fetal deaths with Down syndrome registered in 28 European population-based congenital anomaly registries covering seven m…
A Random Extension for Discriminative Dimensionality Reduction and Metric Learning
2009
A recently proposed metric learning algorithm which enforces the optimal discrimination of the different classes is extended and empirically assessed using different kinds of publicly available data. The optimization problem is posed in terms of landmark points and then, a stochastic approach is followed in order to bypass some of the problems of the original algorithm. According to the results, both computational burden and generalization ability are improved while absolute performance results remain almost unchanged.
Cross-Sectional Associations between Homoarginine, Intermediate Phenotypes, and Atrial Fibrillation in the Community—The Gutenberg Health Study
2018
Homoarginine has come into the focus of interest as a biomarker for cardiovascular disease. Atrial fibrillation (AF) causes a substantial increase in morbidity and mortality. Whether circulating homoarginine is associated with occurrence or persistence of AF and may serve as a new predictive biomarker remains unknown. We measured plasma levels of homoarginine in the population-based Gutenberg health study (3761 patients included, of them 51.7% males), mean age 55.6 ±
Burden and centralised treatment in Europe of rare tumours: results of RARECAREnet—a population-based study
2017
Background: Rare cancers pose challenges for diagnosis, treatments, and clinical decision making. Information about rare cancers is scant. The RARECARE project defined rare cancers as those with an annual incidence of less than six per 100 000 people in European Union (EU). We updated the estimates of the burden of rare cancers in Europe, their time trends in incidence and survival, and provide information about centralisation of treatments in seven European countries. Methods: We analysed data from 94 cancer registries for more than 2 million rare cancer diagnoses, to estimate European incidence and survival in 2000–07 and the corresponding time trends during 1995–2007. Incidence was calcu…