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Sifter-T: A scalable framework for phylogenomic probabilistic protein domain functional annotation
No full textInterface for communication between robotic and cognitive systems through the use of a cognitive ontology
No full textThe demand for socially interactive robots has increased annually. In particular, service robots have invaded homes and worked directly with humans who, in general, are not familiar with such devices. Their acceptance is conditioned to the evolution of research in the area of human-robot interaction. This paper contributes towards this acceptance process presenting an ontology that accelerates the implementation of cognitive systems in robots and enables the reproduction of experiments associated with cognitive models and comparison among different implementations. The specific objective is the definition of an ontology that provides a protocol for communication between cognitive and robot part systems.FAPESP (2013/26453-1
Exploiting different users' interactions for profiles enrichment in recommender systems
No full textUser profiling is an important aspect of recommender systems. It models users' preferences and is used to assess an item's relevance to a particular user. In this paper we propose a profiling approach which describes and enriches the users' preferences using multiple types of interactions. We show in our experiments that the enriched version of users' profiles is able to provide better recommendations.São Paulo Research Foundation (FAPESP) (grants 2013/18698-4 and 2013/22547-1)CNPq (grant 304137/2013-8
Effect of diabetic neuropathy severity classified by a fuzzy model in muscle dynamics during gait
No full textAbstract
Background
Electromyography (EMG) alterations during gait, supposedly caused by diabetic sensorimotor polyneuropathy, are subtle and still inconsistent, due to difficulties in defining homogeneous experimental groups with a clear definition of disease stages. Since evaluating these patients involve many uncertainties, the use of a fuzzy model could enable a better discrimination among different stages of diabetic polyneuropathy and lead to a clarification of when changes in muscle activation start occurring. The aim of this study was to investigate EMG patterns during gait in diabetic individuals with different stages of DSP severity, classified by a fuzzy system.
Methods
147 subjects were divided into a control group (n = 30) and four diabetic groups: absent (n = 43), mild (n = 30), moderate (n = 16), and severe (n = 28) neuropathy, classified by a fuzzy model. The EMG activity of the vastus lateralis, tibialis anterior, and gastrocnemius medialis were measured during gait. Temporal and relative magnitude variables were compared among groups using ANOVA tests.
Results
Muscle activity changes are present even before an established neural involvement, with delay in vastus lateralis peak and lower tibialis anterior relative magnitude. These alterations suggest an impaired ankle shock absorption mechanism, with compensation at the knee. This condition seems to be more pronounced in higher degrees of neuropathy, as there is an increased vastus lateralis activity in the mild and severe neuropathy groups. Tibialis anterior onset at terminal stance was anticipated in all diabetic groups; at higher degrees of neuropathy, the gastrocnemius medialis exhibited activity reduction and peak delay.
Conclusion
EMG alterations in the vastus lateralis and tibialis anterior occur even in the absence of diabetic neuropathy and in mild neuropathic subjects, seemingly causing changes in the shock absorption mechanisms at the heel strike. These changes increase with the onset of neural impairments, and the gastrocnemius medialis starts presenting altered activity in the later stages of the disease (moderate and severe neuropathy). The degree of severity of diabetic neuropathy must be taken into account when analyzing diabetic patients’ biomechanical patterns of locomotion; we recommend the use of a fuzzy model for classification of disease stages
Effect of diabetic neuropathy severity classified by a fuzzy model in muscle dynamics during gait
No full textAbstract
Background
Electromyography (EMG) alterations during gait, supposedly caused by diabetic sensorimotor polyneuropathy, are subtle and still inconsistent, due to difficulties in defining homogeneous experimental groups with a clear definition of disease stages. Since evaluating these patients involve many uncertainties, the use of a fuzzy model could enable a better discrimination among different stages of diabetic polyneuropathy and lead to a clarification of when changes in muscle activation start occurring. The aim of this study was to investigate EMG patterns during gait in diabetic individuals with different stages of DSP severity, classified by a fuzzy system.
Methods
147 subjects were divided into a control group (n = 30) and four diabetic groups: absent (n = 43), mild (n = 30), moderate (n = 16), and severe (n = 28) neuropathy, classified by a fuzzy model. The EMG activity of the vastus lateralis, tibialis anterior, and gastrocnemius medialis were measured during gait. Temporal and relative magnitude variables were compared among groups using ANOVA tests.
Results
Muscle activity changes are present even before an established neural involvement, with delay in vastus lateralis peak and lower tibialis anterior relative magnitude. These alterations suggest an impaired ankle shock absorption mechanism, with compensation at the knee. This condition seems to be more pronounced in higher degrees of neuropathy, as there is an increased vastus lateralis activity in the mild and severe neuropathy groups. Tibialis anterior onset at terminal stance was anticipated in all diabetic groups; at higher degrees of neuropathy, the gastrocnemius medialis exhibited activity reduction and peak delay.
Conclusion
EMG alterations in the vastus lateralis and tibialis anterior occur even in the absence of diabetic neuropathy and in mild neuropathic subjects, seemingly causing changes in the shock absorption mechanisms at the heel strike. These changes increase with the onset of neural impairments, and the gastrocnemius medialis starts presenting altered activity in the later stages of the disease (moderate and severe neuropathy). The degree of severity of diabetic neuropathy must be taken into account when analyzing diabetic patients’ biomechanical patterns of locomotion; we recommend the use of a fuzzy model for classification of disease stages
Malaria and other febrile diseases among travellers: the experience of a reference centre located outside the Brazilian Amazon Region
No full textAbstract\ud
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Background\ud
Malaria is endemic in countries located in tropical and sub-tropical regions. The increasing flow of domestic and international travellers has made malaria a relevant health problem even in non-endemic regions. Malaria has been described as the main diagnosis among travellers presenting febrile diseases after returning from tropical countries. In Brazil, malaria transmission occurs mainly in the Amazon region. Outside this area, malaria transmission is of low magnitude.\ud
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Methods\ud
This cross-sectional study aimed to describe the experience in the diagnosis of malaria in a reference centre located outside the Brazilian Amazon Region, emphasizing the differences in clinical and laboratory markers between cases of malaria and those of other febrile diseases (OFD). Medical charts from adult patients (≥18 years) who underwent a thick smear test (TST) for malaria, between January 2001 and December 2014, were retrospectively reviewed.\ud
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Results\ud
A total of 458 cases referred to perform the TST were included. Malaria was diagnosed in 193 (42 %) episodes. The remaining 265 episodes (58 %) were grouped as OFD. The majority of malaria episodes were acquired in the Brazilian Amazon Region. The median time between the onset of symptoms and the TST was 7 days. Only 53 (11.5 %) episodes were tested within the first 48 h after symptom onset. Comparing malaria with OFD, jaundice, nausea, vomiting, and reports of fever were more prevalent in the malaria group. Low platelet count and elevated bilirubin levels were also related to the diagnosis of malaria.\ud
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Conclusions\ud
The results indicate that outside the endemic area travellers presenting febrile disease suspected of being malaria underwent diagnostic test after considerable delay. The reporting of fever combined with a recent visit to an endemic area should promptly evoke the hypothesis of malaria. In these cases, specific diagnostic tests for malaria should be a priority. For cases that jump this step, the presence of elevated bilirubin or thrombocytopaenia should also indicate a diagnosis of malaria.This work was supported by the Grant # 2014/05337-6, São Paulo Research Foundation (FAPESP)
Hepatitis A and E seroprevalence and associated risk factors: a community-based cross-sectional survey in rural Amazonia
No full textAbstract
Background
Hepatitis A virus (HAV) and hepatitis E virus (HEV) are both transmitted by the faecal-oral route, and represent common causes of acute hepatitis in developing countries. The endemicity of HAV infection has shifted from high to moderate in Brazil. Human cases of HEV infection seem to be rare, although the virus has been detected in swine livestock and effluents of slaughterhouses. This study was to determine the epidemiology of hepatitis A and E in one of the largest agricultural settlements in the Amazon Basin of Brazil.
Methods
Serum samples collected from 397 individuals aged between 5 and 90 years during a population-based cross-sectional survey were tested for anti-HAV and anti-HEV antibodies. Associated risk factors and spatial clustering of HAV and HEV seropositivity were also analyzed.
Results
The overall rate of HAV seropositivity was 82.9% (95% confidence interval (CI), 79.2-86.6%). Multilevel logistic regression analysis identified increasing age (in years; odds ratio (OR), 1.097; 95% CI, 1.050-1.147; P < 0.001) and crowding (OR, 1.603; 95% CI, 1.054-2.440; P = 0.028) as significant risk factors for HAV seropositivity. Anti-HEV IgG was detected in 50/388 settlers (12.9%, 95% CI, 9.5-16.2%). Anti-HEV IgM was detected in 7/43 (16.3%) anti-IgG positive samples, and 4 of them had a confirmed result by immunoblot. Increasing age was the only significant determinant of HEV seropositivity (OR, 1.033; 95% CI, 1.016-1.050; P < 0.001). No significant spatial clustering of HAV and HEV seropositivity was detected in the area.
Conclusions
Both HAV and HEV are endemic, with differing rates of infection in children and adults in this rural setting of the Brazilian Amazon. Anti-HEV prevalence was considerably higher than those previously reported in Brazil. The detection of HEV- specific IgM antibodies in four asymptomatic individuals is highly suggestive of the circulation of HEV in this rural population
The I405V and Taq1B polymorphisms of the CETP gene differentially affect sub-clinical carotid atherosclerosis
No full textAbstract
Background
Cholesteryl ester transfer protein (CETP) plays a major role in lipid metabolism, but studies on the association of CETP polymorphisms with risks of cardiovascular disease are inconsistent. This study investigated whether the CETP gene I405V and Taq1B polymorphisms modified subclinical atherosclerosis in an asymptomatic Brazilian population sample.
Methods
The polymorphisms were analyzed using polymerase chain reaction in 207 adult volunteers. Serum lipid profiles, oxLDL Ab titers, C-reactive protein and tumor necrosis factor-α concentrations and CETP and phospholipid transfer protein (PLTP) activities were determined, and common carotid artery intima-media thickness (cIMT) was measured using ultrasonography.
Results
No differences in cIMT were observed between the presence or absence of the minor B2 and V alleles in either polymorphism. However, inverse correlations between mean cIMT and CETP activity in the presence of these polymorphisms were observed, and positive correlations of these polymorphisms with PLTP activity and oxLDL Ab titers were identified. Moreover, logistic multivariate analysis revealed that the presence of the B2 allele was associated with a 5.1-fold (CI 95%, OR: 1.26 – 21.06) increased risk for cIMT, which was equal and above the 66th percentile and positively interacted with age. However, no associations with the V allele or CETP and PLTP activities were observed.
Conclusions
None of the studied parameters, including CETP activity, explained the different relationships between these polymorphisms and cIMT, suggesting that other non-determined factors were affected by the genotypes and related to carotid atherosclerotic disease
Statistical training of pre-service teachers with application in school practice
No full textThis chapter discusses the way that actions developed under a programme from the Brazilian government can contribute to the learning of teaching, by considering four pre-service mathematics teachers (undergraduate students), from the university in São Paulo, who participated in a training activity using Didactical Sequences (DS) of Statistics, and then applied these to students in their sixth to ninth years of schooling. It is considered that programme has provided training times to pre-service teachers, who learn the necessary concepts for teaching, as well as how to prepare and execute activities in the classroom with the guidance and under the supervision of professors and teachers. Therefore, those activities provide security for pre-service teachers in their teacher training.CAPES (PIBID ICMC-USP)CNPq (472295/2010-1
What is hidden in a heuristic evaluation: tactics from the experts
No full textThe usability of software is recognized as an important factor to develop software quality, capable of improving the efficiency and effectiveness of users. In addition, higher usability increases the satisfaction of customers. One of the most popular and economical accessible methods for usability evaluation is the Heuristic Evaluation (HE). However, the conduction of HE still depends on the participation of expert evaluator to produce the best results with quality; and expert evaluators are expensive and rare to find. Still, a little is know about adaptations of HE for novice evaluators. The development of adaptations to HE that can support the performance of novice evaluators, reducing the costs of applying it, remains as a challenge in the literature. In this context, organizations with a low monetary power rarely conduct usability evaluation in their process of software development. Researches that intend to investigate new approaches to enhance the performance of novice evaluators during HE are highly important to help these organizations to increase the quality of their products and satisfaction of their customers. The purpose of this study was to develop a set of strategies based on the tactics that expert evaluators use during their performance of HE. We conducted a survey with four experts in usability related area in order to collect their main procedures used to perform a HE that are not described in the original method, since it is a lean method. A set of 31 strategies was collected from the survey. All these strategies were raised by the experts aiming to help novice evaluators in their performance of HE. In addition, it can probably fit as a training guide for novice evaluators. However, future studies still have to validate the new set of strategies. Future studies can also explore the potential of the strategies for training novice evaluators.São Paulo Research Foundation (FAPESP) (grant #2015/09493-5