Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Sensors (Basel) ; 23(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37514805

RESUMO

The study of Domain Generalization (DG) has gained considerable momentum in the Machine Learning (ML) field. Human Activity Recognition (HAR) inherently encompasses diverse domains (e.g., users, devices, or datasets), rendering it an ideal testbed for exploring Domain Generalization. Building upon recent work, this paper investigates the application of regularization methods to bridge the generalization gap between traditional models based on handcrafted features and deep neural networks. We apply various regularizers, including sparse training, Mixup, Distributionally Robust Optimization (DRO), and Sharpness-Aware Minimization (SAM), to deep learning models and assess their performance in Out-of-Distribution (OOD) settings across multiple domains using homogenized public datasets. Our results show that Mixup and SAM are the best-performing regularizers. However, they are unable to match the performance of models based on handcrafted features. This suggests that while regularization techniques can improve OOD robustness to some extent, handcrafted features remain superior for domain generalization in HAR tasks.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Humanos , Atividades Humanas , Conscientização , Acelerometria
2.
Sensors (Basel) ; 22(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36236427

RESUMO

Human Activity Recognition (HAR) has been studied extensively, yet current approaches are not capable of generalizing across different domains (i.e., subjects, devices, or datasets) with acceptable performance. This lack of generalization hinders the applicability of these models in real-world environments. As deep neural networks are becoming increasingly popular in recent work, there is a need for an explicit comparison between handcrafted and deep representations in Out-of-Distribution (OOD) settings. This paper compares both approaches in multiple domains using homogenized public datasets. First, we compare several metrics to validate three different OOD settings. In our main experiments, we then verify that even though deep learning initially outperforms models with handcrafted features, the situation is reversed as the distance from the training distribution increases. These findings support the hypothesis that handcrafted features may generalize better across specific domains.


Assuntos
Atividades Humanas , Redes Neurais de Computação , Humanos , Reconhecimento Psicológico
3.
J Heart Valve Dis ; 24(3): 368-75, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26901914

RESUMO

BACKGROUND AND AIM OF THE STUDY: The population of pregnant women with valvular heart disease (VHD), and in particular with valvular heart prostheses (VHPs), represents a unique patient group where data are scarce, and where there is an increased risk for adverse maternal and obstetric events. The study aim was to assess the experience of a tertiary center with regards to cardiac and pregnancy outcomes in women with VHD, comparing VHPs with other VHD pathologies. METHODS: A retrospective analysis of 84 pregnancies in women with VHD (mean age 27.5 ± 5.5 years) was carried out over a 10-year period. Twenty-three pregnancies with VHPs (group A) and 61 with other VHD pathologies (group B) were identified and their cardiac, obstetric, and neonatal outcomes evaluated. RESULTS: At the start of pregnancy, group A included more patients with an impaired left ventricular ejection fraction (LVEF) (15.8% versus 3.9%, p = 0.014), with a previous history of cardiac medication (82.6% versus 29.5%, p = 0.000), and with arrhythmic or ischemic events (18.2% versus 4.9%, p = 0.076). A deterioration in NYHA functional class was the most common cardiac complication (8.3%), and in 7.1% of patients it was necessary to initiate some form of cardiac medication. No maternal deaths were recorded. Group A presented significantly more hemorrhagic and thrombotic complications; all of these events were in women receiving low-molecular-weight heparin. There were 95.5% live births, with a medium birth weight of 3068 ± 498 g. In the VHP group there was also a higher incidence of spontaneous abortion (26.1 versus 3.3, p = 0.005), newborns small for gestational age (30.0 versus 0.4, p = 0.07) and mean Apgar score < 7 (16.7 versus 0.0, p = 0.031). Warfarin embryopathy was observed in one case. CONCLUSION: With the multidisciplinary care provided, pregnancy was relatively well tolerated and successful. However, the presence of a VHP remains a challenging condition that is associated with elevated maternal and fetal morbidity. A worse baseline cardiac status of the mother, as well as anticoagulation issues, were determinants for these findings.


Assuntos
Doenças das Valvas Cardíacas/epidemiologia , Complicações Cardiovasculares na Gravidez/epidemiologia , Resultado da Gravidez , Aborto Espontâneo/epidemiologia , Adulto , Índice de Apgar , Cardiotônicos/uso terapêutico , Feminino , Próteses Valvulares Cardíacas , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Portugal/epidemiologia , Gravidez , Estudos Retrospectivos , Volume Sistólico
4.
Neurology ; 101(16): e1640-e1645, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37527936

RESUMO

Anti-Hu antibodies are associated with autoimmune syndromes, mainly limbic encephalitis, encephalomyelitis, and painful sensory polyneuropathy (Denny-Brown). We report the case of a 15-year-old boy presenting with epilepsia partialis continua (EPC) found to have a right middle frontal gyrus brain lesion without atrophy or contralateral involvement. After partial resection, neuropathology revealed neuronal loss, reactive gliosis and astrocytosis, and perivascular mononuclear inflammatory infiltrate and features of neuronophagia resembling Rasmussen encephalitis. Suboptimal response to antiseizure drugs and surgery prompted further workup with identification of positive serum anti-Hu antibodies and a mediastinal seminoma. The patient was treated with immunotherapy including steroids, IV immunoglobulin, azathioprine, rituximab, plasmapheresis, and mediastinal lesion resection. However, he continued to experience EPC and psychomotor impairment along with left hemiparesis and dysarthria. Given clinical progression with failure to respond to immunotherapy and antiseizure polytherapy, hemispherotomy was attempted and seizure freedom achieved. A review of the literature found only 16 cases of neurologic presentations associated with anti-Hu antibodies in children, confirming the rarity of EPC in these cases. Thus, this report provides a new observation of germ cell mediastinal tumor associated with anti-Hu antibodies in children, broadening the spectrum of anti-Hu-associated neurologic disorders in children and highlighting the importance of considering antineuronal antibody testing in children presenting with EPC and brain lesions suggestive of Rasmussen encephalitis.


Assuntos
Encefalite , Epilepsia Parcial Contínua , Neoplasias do Mediastino , Neurologia , Seminoma , Neoplasias Testiculares , Adolescente , Humanos , Masculino , Encefalite/complicações , Encefalite/terapia , Epilepsia Parcial Contínua/complicações , Imageamento por Ressonância Magnética , Neoplasias do Mediastino/complicações , Neoplasias do Mediastino/terapia , Seminoma/complicações , Neoplasias Testiculares/complicações , Neoplasias Testiculares/terapia
5.
Arch Endocrinol Metab ; 66(2): 229-236, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35420265

RESUMO

Objective: Evaluate the celiac disease (CD) markers, within the scope of its screening, in a pediatric population with diagnosis of type 1 diabetes (T1D) at Hospital de Braga (HB) and determine the prevalence of CD in the sample. Reflect on CD screening algorithm applied in this pediatric population. Methods: Retrospective observational study with 94 patients diagnosed with T1D at age 10 years or younger, followed up at the HB Outpatient Diabetology Consultation, including those referred from other hospitals. Record of clinical information, IgA anti-transglutaminase and anti-endomysium and HLA DQ2/DQ8 haplotypes. Results: We obtained positive serological test for CD in 4 patients. This test had 100% sensitivity and specificity. The prevalence of CD was 4.3% (n = 4). Positive HLA screening in 84.6% of patients, with both sensitivity and negative predictive value of 100% and specificity of 16.67%. Diagnosis of CD was made on average 3.40 ± 3.32 years after the diagnosis of TD1. All cases of CD registered non-gastrointestinal manifestations, none had gastrointestinal symptoms. Conclusion: This study proved that there is a higher prevalence of CD in pediatric population with TD1, when compared to general population, and clarified the importance of CD screening. Furthermore, it was observed that serological screening for CD antibodies is an excellent screening test and HLA typing, although not the most suitable first line test, can be useful in excluding the possibility of patients with T1D developing CD.


Assuntos
Autoanticorpos , Doença Celíaca , Diabetes Mellitus Tipo 1 , Antígenos HLA-DQ , Doença Celíaca/diagnóstico , Doença Celíaca/genética , Criança , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Antígenos HLA-DQ/genética , Haplótipos , Humanos , Estudos Retrospectivos , Transglutaminases/imunologia
6.
Arch. endocrinol. metab. (Online) ; 66(2): 229-236, Apr. 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1374276

RESUMO

ABSTRACT Objectives: Evaluate the celiac disease (CD) markers, within the scope of its screening, in a pediatric population with diagnosis of type 1 diabetes (T1D) at Hospital de Braga (HB) and determine the prevalence of CD in the sample. Reflect on CD screening algorithm applied in this pediatric population. Subjects and methods: Retrospective observational study with 94 patients diagnosed with T1D at age 10 years or younger, followed up at the HB Outpatient Diabetology Consultation, including those referred from other hospitals. Record of clinical information, IgA anti-transglutaminase and anti-endomysium and HLA DQ2/DQ8 haplotypes. Results: We obtained positive serological test for CD in 4 patients. This test had 100% sensitivity and specificity. The prevalence of CD was 4.3% (n = 4). Positive HLA screening in 84.6% of patients, with both sensitivity and negative predictive value of 100% and specificity of 16.67%. Diagnosis of CD was made on average 3.40 ± 3.32 years after the diagnosis of TD1. All cases of CD registered non-gastrointestinal manifestations, none had gastrointestinal symptoms. Conclusion: This study proved that there is a higher prevalence of CD in pediatric population with TD1, when compared to general population, and clarified the importance of CD screening. Furthermore, it was observed that serological screening for CD antibodies is an excellent screening test and HLA typing, although not the most suitable first line test, can be useful in excluding the possibility of patients with T1D developing CD.

7.
J Bras Nefrol ; 34(3): 291-2, 2012.
Artigo em Português | MEDLINE | ID: mdl-23099837

RESUMO

Glycosuria as an accidental finding implies a diagnostic workout. We present the cases of two asymptomatic female teenagers referred to a hospital outpatient clinic due to isolated glycosuria detected in a routine analysis. The diagnostic workout revealed isolated glycosuria in the absence of other abnormalities. The genetic study confirmed the diagnosis of renal glycosuria, by revealing SCL5A2 gene mutations. Renal glycosuria is characterized by persistent glycosuria in the absence of hyperglycaemia or generalized renal tubular dysfunction. It's usually asymptomatic and has good prognosis. The authors call the attention to this rare entity, since it can be the reason for reference to a hospital outpatient clinic, underlining the importance of a differential diagnosis with more serious diseases that require proper treatment.


Assuntos
Glicosúria Renal/diagnóstico , Adolescente , Feminino , Humanos
8.
J. bras. nefrol ; 34(3): 291-292, jul.-set. 2012.
Artigo em Português | LILACS | ID: lil-653548

RESUMO

A glicosúria como achado acidental implica um estudo etiológico. Apresentam-se os casos de duas adolescentes do sexo feminino, assintomáticas, referenciadas por glicosúria detectada em análise de rotina. Negavam infecções, traumatismos e ingestão de fármacos ou tóxicos. O estudo efetuado confirmou glicosúria na ausência de outras alterações. O estudo genético revelou a presença de mutações do gene SCL5A2, confirmando o diagnóstico de glicosúria renal. A glicosúria renal familiar caracteriza-se por glicosúria isolada persistente na ausência de hiperglicemia e de disfunção tubular renal generalizada. É, geralmente, assintomática e o prognóstico é favorável. Alerta-se para esta rara entidade, pois pode ser motivo de referenciação para consulta de pediatria, salientando-se a importância do diagnóstico diferencial com afecções mais graves que necessitam de tratamento adequado.


Glycosuria as an accidental finding implies a diagnostic workout. We present the cases of two asymptomatic female teenagers referred to a hospital outpatient clinic due to isolated glycosuria detected in a routine analysis. The diagnostic workout revealed isolated glycosuria in the absence of other abnormalities. The genetic study confirmed the diagnosis of renal glycosuria, by revealing SCL5A2 gene mutations. Renal glycosuria is characterized by persistent glycosuria in the absence of hyperglycaemia or generalized renal tubular dysfunction. It's usually asymptomatic and has good prognosis. The authors call the attention to this rare entity, since it can be the reason for reference to a hospital outpatient clinic, underlining the importance of a differential diagnosis with more serious diseases that require proper treatment.


Assuntos
Adolescente , Feminino , Humanos , Glicosúria Renal/diagnóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA