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1.
Conscious Cogn ; 100: 103317, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35364385

RESUMO

AIM: This study investigated the bromazepam effects in male subjects during the time estimation performance and EEG alpha asymmetry in electrodes associated with the frontal and motor cortex. MATERIAL AND METHODS: This is a double-blind, crossover study with a sample of 32 healthy adults under control (placebo) vs. experimental (bromazepam) during visual time-estimation task in combination with electroencephalographic analysis. RESULTS: The results demonstrated that the bromazepam increased the relative error in the 4 s, 7 s, and 9 s intervals (p = 0.001). In addition, oral bromazepam modulated the EEG alpha asymmetry in cortical areas during the time judgment (p ≤ 0.025). CONCLUSION: The bromazepam decreases the precision of time estimation judgments and modulates the EEG alpha asymmetry, with greater left hemispheric dominance during time perception. Our findings suggest that bromazepam influences internal clock synchronization via the modulation of GABAergic receptors, strongly relating to attention, conscious perception, and behavioral performance.


Assuntos
Bromazepam , Percepção do Tempo , Adulto , Bromazepam/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Eletroencefalografia/métodos , Humanos , Julgamento , Masculino
2.
Front Artif Intell ; 5: 1025148, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714206

RESUMO

Reversibility in artificial neural networks allows us to retrieve the input given an output. We present feature alignment, a method for approximating reversibility in arbitrary neural networks. We train a network by minimizing the distance between the output of a data point and the random output with respect to a random input. We applied the technique to the MNIST, CIFAR-10, CelebA, and STL-10 image datasets. We demonstrate that this method can roughly recover images from just their latent representation without the need of a decoder. By utilizing the formulation of variational autoencoders, we demonstrate that it is possible to produce new images that are statistically comparable to the training data. Furthermore, we demonstrate that the quality of the images can be improved by coupling a generator and a discriminator together. In addition, we show how this method, with a few minor modifications, can be used to train networks locally, which has the potential to save computational memory resources.

3.
Neurol Sci ; 40(4): 829-837, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30693423

RESUMO

Methylphenidate produces its effects via actions on cortical areas involved with attention and working memory, which have a direct role in time estimation judgment tasks. In particular, the prefrontal and parietal cortex has been the target of several studies to understand the effect of methylphenidate on executive functions and time interval perception. However, it has not yet been studied whether acute administration of methylphenidate influences performance in time estimation task and the changes in alpha band absolute power in the prefrontal and parietal cortex. The current study investigates the influence of the acute use of methylphenidate in both performance and judgment in the time estimation interpretation through the alpha band absolute power activity in the prefrontal and parietal cortex. This is a double-blind, crossover study with a sample of 32 subjects under control (placebo) and experimental (methylphenidate) conditions with absolute alpha band power analysis during a time estimation task. We observed that methylphenidate does not influence task performance (p > 0.05), but it increases the time interval underestimation by over 7 s (p < 0.001) with a concomitant decrease in absolute alpha band power in the ventrolateral prefrontal cortex and dorsolateral prefrontal cortex and parietal cortex (p < 0.001). Acute use of methylphenidate increases the time interval underestimation, consistent with reduced accuracy of the internal clock mechanisms. Furthermore, acute use of methylphenidate influences the absolute alpha band power over the dorsolateral prefrontal cortex, ventrolateral prefrontal cortex, and parietal cortex.


Assuntos
Ritmo alfa/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Julgamento/efeitos dos fármacos , Metilfenidato/farmacologia , Lobo Parietal/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Tempo de Reação/efeitos dos fármacos , Percepção do Tempo/efeitos dos fármacos , Adulto , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/efeitos adversos , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Metilfenidato/administração & dosagem , Metilfenidato/efeitos adversos , Adulto Jovem
4.
Sci Total Environ ; 630: 544-559, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29494966

RESUMO

The analysis of vehicle cold start emissions has become an issue of utmost importance since the cold phase occurs mainly in urban context, where most of the population lives. In this sense, this research work analyzes and quantifies the impacts of cold start in urban context using naturalistic driving data. Furthermore, an assessment of the influence of ambient temperature on the percentage of time spent on cold start was also performed. Regarding the impacts of ambient temperature on cold start duration, a higher percentage of time spent on cold start was found for lower ambient temperatures (80% of the time for 0°C and ~50% for 29°C). Results showed that, during cold start, energy consumption is >110% higher than during hot conditions while emissions are up to 910% higher. Moreover, a higher increase on both energy consumption and emissions was found for gasoline vehicles than for diesel vehicles. When assessing the impacts on a city perspective, results revealed that the impacts of cold start increase for more local streets. The main finding of this study is to provide evidence that a higher increase on emissions occurs on more local streets, where most of the population lives. This kind of knowledge is of particular relevance to urban planners in order to perform an informed definition of public policies and regulations to be implemented in the future, to achieve a cleaner and healthier urban environment.

5.
Neurol Int ; 10(4): 7326, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30687464

RESUMO

The visual acuity loss enables the brain to access new pathways in the quest to overcome the visual limitation and this is wellknown as neuroplasticity which have mechanisms to cortical reorganization. In this review, we related the evidences about the neuroplasticity as well as cortical anatomical differences and functional repercussions in visual impairments. We performed a systematic review of PUBMED database, without date or status publication restrictions. The findings demonstrate that the visual impairment produce a compensatory sensorial effect, in which non-visual areas are related to both cross (visual congenital) and multimodal (late blind) neuroplasticity.

6.
Environ Sci Pollut Res Int ; 24(13): 12026-12037, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-26490899

RESUMO

Air quality in urban centers constitutes a challenge ahead for most cities. For this reason, the objective of this research work was to evaluate the impacts of changing traffic-related parameters on particulate matter (PM) concentration for several hierarchical street levels using real-world data for the city of Lisbon, Portugal. For that purpose, 2014 data regarding meteorological conditions, traffic volumes, typical vehicle speed, and a vehicle representative of the fleet was used in an air quality dispersion model (CALINE4). The available data allowed building a baseline case for several streets that are representative of the traffic circulation conditions in Lisbon, which was compared with different scenarios: hypothetical introduction of a cordon toll (S1.1 to S1.4) and the implementation of a low emission zone (S2.1 and 2.2). The results indicate that reductions on PM2.5 concentrations from 5 to 42 % may be obtained from the implementation of the scenarios. Overall, this study demonstrates that modeling tools based on real-world data can provide a good approach to study urban policies regarding traffic-related PM exposure. Additionally, implementation of such measures requires an integrated strategy that enables proper enforcement and monitoring, as well as an adequate management of traffic flows between the implementation boundaries.


Assuntos
Poluição do Ar/análise , Monitoramento Ambiental , Emissões de Veículos , Poluentes Atmosféricos/análise , Cidades , Material Particulado/análise , Portugal
7.
Int J Occup Med Environ Health ; 27(2): 216-23, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24700159

RESUMO

OBJECTIVES: The aim of this study was to verify and analyze the existence of chronic adaptations of lung function in free-diving fishermen whose occupation is artisanal fishing. MATERIAL AND METHODS: This was a cross-sectional study involving 11 breath-hold diving fishermen and 10 non-breath-hold diving fishermen (control) from the village of Bitupitá in the municipality of Barroquinha (Ceará - Brazil). Anthropometric measurements, chest and abdominal circumferences as well as spirometric and respiratory muscle strength tests were conducted according to the specifications of the American Thoracic Society/European Respiratory Society (ATS/ERS). In order to compare the measured values versus the predicted values, Student t test was used in the case of parametric test and Wilcoxon test in the case of nonparametric test. To compare the inter-group means Student t test was used for parametric test and Mann-Whitney test for the nonparametric one. The level of significance was set at α = 5%. RESULTS: The forced vital capacity (FVC) (4.9 ± 0.6 l vs. 4.3 ± 0.4 l) and forced expiratory volume in 1 s (FEV1) (4.0 ± 0.5 l vs. 3.6 ± 0.3 l) were, respectively, higher in the group of divers compared to the control group (p ≤ 0.05). Furthermore, in the group of free divers, the measured FVC, FEV1 and FEV1/FVC ratios were significantly greater than the predicted ones. No differences were found between the measured respiratory pressures. CONCLUSIONS: These results indicate that breath-hold diving seems to produce chronic adaptations of the respiratory system, resulting in elevated lung volumes with no airway obstruction.


Assuntos
Adaptação Fisiológica , Suspensão da Respiração , Mergulho/fisiologia , Indústria Alimentícia , Alimentos Marinhos , Adulto , Estudos Transversais , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Capacidade Vital
8.
J Pediatr Urol ; 9(6 Pt A): 945-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23462384

RESUMO

OBJECTIVE: To evaluate the prevalence of constipation in children with isolated overactive bladder (IOAB) and no micturition complaints. MATERIALS AND METHODS: A questionnaire was used to evaluate constipation in 51 children with IOAB, as well as in a control group of 74 children between the ages of 4 and 14 years. The Rome III criteria for children were used to assess constipation. IOAB was defined as the presence of symptoms such as urgency with or without daytime incontinence or frequency, a bell-shaped uroflow, and no post-residual urine. RESULTS: Mean patient ages were 7.94 (±2.8) and 8.28 (±3.4) years in the OAB and control group, respectively (p = 0.54). Twenty-eight (54.9%) of the OAB group were girls, and 34 (45.9%) were girls in the control group (p = 0.32). More of the children with IOAB had constipation than those without urinary symptoms (54.9% vs. 29.7%, p = 0.005; or 2.87, 95% CI: 1.3-6.0). The results were statistically significant regarding the following Rome III criteria: "history of stool retention", "presence of painful or hard bowel movements", "the presence of a large fecal mass in the rectum" and "large diameter stools which may obstruct the toilet". Within the group with OAB, constipation was more common among males (p = 0.05). There was no association between the type of OAB symptoms and constipation. The average dysfunctional voiding symptom score was 9.76 (±4.1). Eleven children (21.6%) presented alterations on ultrasound. Girls with OAB presented more frequently with UTI than boys (18 vs. 10, p = 0.13). CONCLUSION: This was the first comparative study with respect to constipation in children with IOAB and without urinary symptoms. Children with IOAB have a greater risk of having constipation compared to those with no urinary symptoms.


Assuntos
Constipação Intestinal/epidemiologia , Bexiga Urinária Hiperativa/epidemiologia , Micção , Adolescente , Criança , Pré-Escolar , Enurese Diurna/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Distribuição por Sexo , Inquéritos e Questionários , Incontinência Urinária de Urgência/epidemiologia
9.
J Urol ; 190(2): 673-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23422257

RESUMO

PURPOSE: Parasacral transcutaneous electrical nerve stimulation and posterior tibial nerve stimulation have emerged as effective methods to treat overactive bladder in children. However, to our knowledge no study has compared the 2 methods. We evaluated the results of parasacral transcutaneous electrical nerve stimulation and posterior tibial nerve stimulation in children with overactive bladder. MATERIALS AND METHODS: We prospectively studied children with overactive bladder without dysfunctional voiding. Success of treatment was evaluated by visual analogue scale and dysfunctional voiding symptom score, and by level of improvement of each specific symptom. Parasacral transcutaneous electrical nerve stimulation was performed 3 times weekly and posterior tibial nerve stimulation was performed once weekly. RESULTS: A total of 22 consecutive patients were treated with posterior tibial nerve stimulation and 37 with parasacral transcutaneous electrical nerve stimulation. There was no difference between the 2 groups regarding demographic characteristics or types of symptoms. Concerning the evaluation by visual analogue scale, complete resolution of symptoms was seen in 70% of the group undergoing parasacral transcutaneous electrical nerve stimulation and in 9% of the group undergoing posterior tibial nerve stimulation (p = 0.02). When the groups were compared, there was no statistically significant difference (p = 0.55). The frequency of persistence of urgency and diurnal urinary incontinence was nearly double in the group undergoing posterior tibial nerve stimulation. However, this difference was not statistically significant. CONCLUSIONS: We found that parasacral transcutaneous electrical nerve stimulation is more effective in resolving overactive bladder symptoms, which matches parental perception. However, there were no statistically significant differences in the evaluation by dysfunctional voiding symptom score, or in complete resolution of urgency or diurnal incontinence.


Assuntos
Terapia por Estimulação Elétrica/métodos , Sacro/inervação , Nervo Tibial , Bexiga Urinária Hiperativa/terapia , Distribuição de Qui-Quadrado , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Estatísticas não Paramétricas , Inquéritos e Questionários , Estimulação Elétrica Nervosa Transcutânea/métodos , Resultado do Tratamento
10.
J Pediatr Urol ; 9(5): 622-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22857873

RESUMO

OBJECTIVE: To evaluate the efficacy of parasacral transcutaneous electrical nerve stimulation (TENS) for the treatment of constipation in children with lower urinary tract dysfunction (LUTD). MATERIALS AND METHODS: We treated 9 boys and 5 girls with a mean age of 8.07 ± 2.72 years. 10 (71.4%) had overactive bladder and 4 (28.6%) had voiding dysfunction. A total of 20 parasacral TENS sessions, 20 min each (10 Hz), were performed 3 times per week. The criteria used to assess constipation were the Rome III criteria for children, the Bristol Stool Chart, and a visual analog scale (pain from 0 to 10). The children were reassessed immediately after treatment. No specific treatment of constipation was performed. RESULTS: After treatment, 85.7% (p < 0.001) of the children's constipation symptoms had improved following the Rome III criteria. Parasacral TENS significantly impacted the following symptoms: "the presence of at least one episode of fecal incontinence per week", "history of stool retention", and "the presence of a large fecal mass in the rectum." There was no significant change in the Bristol Stool Chart evaluation (p < 0.25), but there was a significant improving trend in level of pain before and after treatment (p < 0.063). All urinary symptoms evaluated showed improvement after TENS treatment. There was a decrease in post-void residual urine. CONCLUSION: In this first study to evaluate the results of parasacral TENS on constipation in children with LUTD, satisfactory results were obtained for both complaints.


Assuntos
Constipação Intestinal/terapia , Terapia por Estimulação Elétrica , Sintomas do Trato Urinário Inferior/terapia , Criança , Pré-Escolar , Constipação Intestinal/classificação , Constipação Intestinal/complicações , Constipação Intestinal/diagnóstico , Feminino , Humanos , Sintomas do Trato Urinário Inferior/complicações , Masculino , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
11.
Fisioter. Bras ; 12(6): 442-446, Nov.-Dez.2011.
Artigo em Português | LILACS | ID: lil-785442

RESUMO

Crianças adaptam-se rapidamente a uma nova postura e, se esteposicionamento for inadequado, pode acarretar em comprometimentoscorporais, prejudicando sua postura. Os padrões posturaisassumidos na infância progressivamente podem formar a posturado adulto. São inúmeras as variáveis que influenciam a ergonomiacorporal, dentre elas estão os distúrbios no equilíbrio escapular.Este estudo objetivou analisar quantitativamente as alteraçõesescapulares em escolares no município de Parnaíba/PI. Trata-se deum estudo transversal, onde foi realizada uma avaliação posturalem 148 crianças entre 10 e 12 anos de ambos os sexos. O testeutilizado na análise da verificação da variação de frequências e dograu de associação entre as variáveis foi o Qui-Quadrado. O nívelde significância estabelecido foi o equivalente a p < 0,05. O presenteestudo observou as seguintes alterações no equilíbrio estáticoda cintura escapular: (5,2%) protusão, (16,5%) adução, (20,6%)abdução, (27,8%) elevação. A taxa de normalidade foi 29,9%. Aalteração escapular mais comum nos alunos avaliados foi a elevaçãoescapular com 27,8%. Concluiu-se que 66,2% dos escolaresavaliados apresentaram alterações do alinhamento escapular e aocompararmos as outras alterações, há variação significativamentedistinta na prevalência da adução e protusão escapular...


Children adapt quickly to a new position but, if this position isinadequate, can lead to physical impairments, affecting definitivelythe posture. The postural patterns in childhood can gradually modifythe adult posture. There are numerous variables that influence thebody posture, among which are disturbances in the scapular balance.This study aimed to quantitatively analyze the changes in scapularbalance in children at Parnaíba/PI. It was a cross-sectional study onpostural evaluation in 148 children of both genders, 10 to 12 yearsold. The tests used in the analysis of verification of frequency rangesand the degree of association between variables were chi-square. Thesignificance level was equivalent to p < 0.05. The present study observedthe following changes in static balance of the shoulder girdle:(5.2%) protrusion, (16.5%) adduction, (20.6%) abduction (27.8%)increase. The rate of normality was 29.9%. The most commonchange in scapular balance students was elevation with 27.8%. It wasconcluded that 66.2% of schoolchildren present scapular alignmentchanges and, comparing to other changes, they present a significantprevalence of scapular adduction and protrusion...


Assuntos
Humanos , Fenômenos Biomecânicos , Criança , Equilíbrio Postural , Postura
12.
J Air Waste Manag Assoc ; 59(8): 912-24, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19728485

RESUMO

The objective of this research is to evaluate differences in fuel consumption and tailpipe emissions of flexible fuel vehicles (FFVs) operated on ethanol 85 (E85) versus gasoline. Theoretical ratios of fuel consumption and carbon dioxide (CO2) emissions for both fuels are estimated based on the same amount of energy released. Second-by-second fuel consumption and emissions from one FFV Ford Focus fueled with E85 and gasoline were measured under real-world traffic conditions in Lisbon, Portugal, using a portable emissions measurement system (PEMS). Cycle average dynamometer fuel consumption and emission test results for FFVs are available from the U.S. Department of Energy, and emissions certification test results for ethanol-fueled vehicles are available from the U.S. Environmental Protection Agency. On the basis of the PEMS data, vehicle-specific power (VSP)-based modal average fuel and emission rates for both fuels are estimated. For E85 versus gasoline, empirical ratios of fuel consumption and CO2 emissions agree within a margin of error to the theoretical expectations. Carbon monoxide (CO) emissions were found to be typically lower. From the PEMS data, nitric oxide (NO) emissions associated with some higher VSP modes are higher for E85. From the dynamometer and certification data, average hydrocarbon (HC) and nitrogen oxides (NOx) emission differences vary depending on the vehicle. The differences of average E85 versus gasoline emission rates for all vehicle models are -22% for CO, 12% for HC, and -8% for NOx emissions, which imply that replacing gasoline with E85 reduces CO emissions, may moderately decrease NOx tailpipe emissions, and may increase HC tailpipe emissions. On a fuel life cycle basis for corn-based ethanol versus gasoline, CO emissions are estimated to decrease by 18%. Life-cycle total and fossil CO2 emissions are estimated to decrease by 25 and 50%, respectively; however, life-cycle HC and NOx emissions are estimated to increase by 18 and 82%, respectively.


Assuntos
Poluentes Atmosféricos/análise , Fontes de Energia Bioelétrica , Dióxido de Carbono/análise , Etanol/química , Gasolina/análise , Emissões de Veículos/análise , Modelos Teóricos
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