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Supervised machine learning algorithms are powerful classification techniques commonly used to build prediction models that help diagnose the disease early. However, some challenges like overfitting and underfitting need to be overcome while building the model. This paper introduces hybrid classifiers using the ensembled model with a majority voting technique to improve prediction accuracy. Furthermore, a proposed preprocessing technique and features selection based on a genetic algorithm is suggested to enhance prediction performance and overall time consumption. In addition, the 10-folds cross-validation technique is used to overcome the overfitting problem. Experiments were performed on a dataset for cardiovascular patients from the UCI Machine Learning Repository. Through a comparative analytical approach, the study results indicated that the proposed ensemble classifier model achieved a classification accuracy of 98.18% higher than the rest of the relevant developments in the study.

OBJETIVO: Estudar a concordância no diagnóstico radiológico das infecções respiratórias agudas baixas em crianças. MÉTODOS: Sessenta radiogramas do tórax de crianças menores de cinco anos foram avaliados, individualmente, por três médicos: um radiologista pediátrico (RP), um pneumologista pediatra (PP) e um pediatra experiente no atendimento de sala de emergência (PE). Todas as crianças tinham procurado atendimento por apresentar um quadro agudo de infecção respiratória com aparente participação pulmonar. Os avaliadores desconheciam os diagnósticos originais, mas receberam uma ficha padrão com dados clínicos e laboratoriais dos pacientes no momento da consulta inicial. As variáveis investigadas foram agrupadas em cinco categorias: a) qualidade técnica do filme; b) localização da alteração; c) padrões radiográficos; d) outras alterações radiográficas; e) diagnóstico. Utilizou-se a estatística de Kappa para estudar a concordância entre as três duplas possíveis de observadores, aceitando-se os valores ajustados para viés de prevalência (KAVIP). RESULTADOS: Os valores de Kappa totais de cada dupla de observadores (RP x PP, RP x PE e PP x PE) foram 0,41, 0,43, e 0,39, respectivamente, o que representa, em média, uma concordância interobservadores moderada (0,41). Em relação às outras variáveis, "qualidade técnica" teve uma concordância regular (0,30); "localização", moderada (0,48); "padrões radiográficos" regular (0,29); "outras alterações radiográficas", moderada (0,43); e "diagnóstico", regular (0,33). Quanto à concordância global intraobservadores, a mesma foi moderada (0,54), com valores menores do que os descritos na literatura. CONCLUSÕES: A variabilidade interobservadores é inerente à interpretação dos achados radiológicos. A determinação do diagnóstico exato das infecções respiratórias agudas baixas nas crianças impõe desafios. Nossos resultados foram similares aos descritos na literatura.

Two cases of scimitar syndrome in children under one-year old are presented. Both were repaired through a right thoracotomy, off-pump, reimplanting the venous collector in the left atrium. Tips and advantages are discussed.

Objective: To determine whether air trapping (expressed as the percentage of air trapping relative to total lung volume [AT%]) correlates with clinical and functional parameters in children with obliterative bronchiolitis (OB)., Methods: CT scans of 19 children with OB were post-processed for AT% quantification with the use of a fixed threshold of -950 HU (AT%950) and of thresholds selected with the aid of density masks (AT%DM). Patients were divided into three groups by AT% severity. We examined AT% correlations with oxygen saturation (SO2) at rest, six-minute walk distance (6MWD), minimum SO2 during the six-minute walk test (6MWT_SO2), FVC, FEV1, FEV1/FVC, and clinical parameters., Results: The 6MWD was longer in the patients with larger normal lung volumes (r = 0.53). We found that AT%950 showed significant correlations (before and after the exclusion of outliers, respectively) with the clinical score (r = 0.72; 0.80), FVC (r = 0.24; 0.59), FEV1 (r = -0.58; -0.67), and FEV1/FVC (r = -0.53; r = -0.62), as did AT%DM with the clinical score (r = 0.58; r = 0.63), SO2 at rest (r = -0.40; r = -0.61), 6MWT_SO2 (r = -0.24; r = -0.55), FVC (r = -0.44; r = -0.80), FEV1 (r = -0.65; r = -0.71), and FEV1/FVC (r = -0.41; r = -0.52)., Conclusions: Our results show that AT% correlates significantly with clinical scores and pulmonary function test results in children with OB.

A pacemaker insertion through the azygos vein in a child is presented. When both the low weight of the child and mediastinitis precluded standard approaches, the azygos approach proved to be an alternative and a straightforward bailout solution.

The aims of this study were to determine whether infants and toddlers with chronic lung disease of infancy (CLDI) have smaller airways and lower lung density compared with full-term healthy controls. Multi-slice computed tomography (CT) chest scans were obtained at elevated lung volumes during a brief respiratory pause in sedated infants and toddlers; 38 CLDI were compared with 39 full-term controls. For CLDI subjects, gestational age at birth ranged from 25 to 29 weeks. Airway size was measured for the trachea and the next three to four generations into the right lower lobe; lung volumes and tissue density were also measured. The relationship between airway size and airway generation differed between the CLDI and full-term groups; the sizes of the first and second airway generations were larger in the shorter CLDI than in the shorter full-term subjects. The increased size in the airways in the CLDI subjects was associated with increasing mechanical ventilation time in the neonatal period. CLDI subjects had a greater heterogeneity of lung density compared with full-term subjects. Our results indicate that quantitative analysis of multi-slice CT scans at elevated volumes provides important insights into the pulmonary pathology of infants and toddlers with CLDI.

External characteristics of the leaf epidermis and their effects on behaviour of Aphis gossypii Glover were evaluated in two Cucumis melo L. genotypes, 'Bola de Oro' (aphid susceptible) and TGR-1551 (aphid resistant) in order to explore their role in the early rejection of TGR-1551 by this aphid. No differential effects of epicuticular waxes on aphid behaviour were observed. The type, distribution and number of trichomes on melon leaves were also studied. Pubescence in melon, measured as the number of non-glandular trichomes per cm(2), was not sufficient to prevent aphid settling. However, there was a high density of type I glandular trichomes on leaves of the aphid-resistant genotype. According to microscopic observations and stain testing, these trichomes store and secrete phenols and flavonoids. Free-choice tests were conducted to determine the effect of these glandular trichomes on A. gossypii preference, revealing that aphids reject leaf disks of TGR-1551 from the onset of the experiment. Additional experiments after removal of leaf type I glandular trichome exudates showed that A. gossypii preferred washed TGR-1551 leaf disks over unwashed disks, while this effect was not observed in experiments using washed and unwashed 'Bola de Oro' leaf disks. These results suggest that a high density of glandular trichomes and chemicals secreted by them deter A. gossypii and disturb aphid settling on TGR-1551.

Objective: To evaluate the inter-observer agreement of radiological diagnosis of lower respiratory tract infections in children., Methods: Chest X-rays from 60 children younger than 5 years of age were evaluated by three physicians: a pediatric radiologist (PR), a pediatric pulmonologist (PP) and an experienced emergency pediatrician (EP). All children had sought an emergency room due to acute respiratory infections with apparent lower respiratory tract involvement. Observers were blinded to the original diagnostic conclusions, but clinical and laboratory data from the initial medical evaluation were provided with each film. Variables were grouped into five categories: a) film quality; b) site of abnormality; c) radiological patterns; d) other radiographic images; e) diagnosis. Inter-observer agreement was assessed using Kappa statistics, accepting prevalence-bias-adjusted values (PABAK). compare the prevalence of breastfeeding and exclusive breastfeeding during the first six months of life among pacifier and non-pacifier users., Results: Kappa values for each of the three observer pairs (RP vs. PP, RP vs. EP, and PP vs. PE) were 0.41, 0.43, and 0.39, respectively. The overall inter-observer agreement was moderate (0.41). Agreement on other variables was as follows: regular for "film quality" (0.30); moderate for "site of abnormality" (0.48); fair for "radiological patterns" (0.29); moderate for "other radiographic images" (0,43); and moderate for "diagnosis" (0.33). The overall intra-observer agreement was "moderate" (0.54), which is below the agreement values reported by other studies on chest X-ray variability., Conclusions: Inter-observer variability is an intrinsic characteristic of the interpretation of chest X-rays, and the diagnosis of lower respiratory tract infections in children remains a challenge. Most of our results were similar to those previously reported.