Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
ChemSusChem ; 16(21): e202300719, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37548998

RESUMO

Nanosecond time-resolved X-ray (tr-XAS) and optical transient absorption spectroscopy (OTA) are applied to study 3 multimolecular photocatalytic systems with [Ru(bpy)3 ]2+ photoabsorber, ascorbic acid electron donor and Co catalysts with methylene (1), hydroxomethylene (2) and methyl (3) amine substituents in pure water. OTA and tr-XAS of 1 and 2 show that the favored catalytic pathway involves reductive quenching of the excited photosensitizer and electron transfer to the catalyst to form a CoII square pyramidal intermediate with a bonded aqua molecule followed by a CoI square planar derivative that decays within ≈8 µs. By contrast, a CoI square pyramidal intermediate with a longer decay lifetime of ≈35 µs is formed from an analogous CoII geometry for 3 in H2 O. These results highlight the protonation of CoI to form the elusive hydride species to be the rate limiting step and show that the catalytic rate can be enhanced through hydrogen containing pendant amines that act as H-H bond formation proton relays.

2.
BMJ Open ; 12(11): e061988, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36328390

RESUMO

INTRODUCTION: Treadmill training and virtual reality have been investigated in children with cerebral palsy. However, few studies have assessed the effectiveness of the combination of both treatments on children's functional and balance activities. The project aims to compare the effects of treadmill training with and without virtual reality on walking endurance and speed, static and dynamic balance, gross motor function, functional independence, quality of life and occupational participation in children with spastic cerebral palsy between the ages of 4 and 12 years classified at levels I, II and III of the Gross Motor Function Classification System. METHODS AND ANALYSIS: This study is a single-blind, two-arm parallel group, randomised, controlled clinical trial. Participants will be recruited at the Pediatric Department of the Vic Hospital Consortium, and the research will be conducted at the University of Vic - Central University of Catalonia. The participants will be randomly allocated into two groups: (1) the experimental group, which will receive the treadmill training at the same time as the virtual reality; and (2) the control group, which will undertake treadmill gait training alone. The training will be provided in 10 sessions over 2 weeks with 30 min for each session. Assessments will be performed on three occasions: 1 week before the intervention, 1 week following the intervention and 1 month after the end of the intervention. The evaluations will involve the 6 min walk test, stabilometry, the Berg Balance Scale, the 10 m walk test, the Gross Motor Function Measure, the Functional Independence Measure, the paediatric quality of life inventory and the Children Participation Questionnaire. For between-within group comparison, a mixed-effect linear model will be used. ETHICS AND DISSEMINATION: The study has been approved by the Clinical Research Ethics Committee of the Osona Foundation for Health Research and Education (2021061). Results will be published in peer-reviewed journals and presented at international conferences. TRIAL REGISTRATION NUMBER: NCT05131724.


Assuntos
Paralisia Cerebral , Realidade Virtual , Criança , Humanos , Pré-Escolar , Método Simples-Cego , Qualidade de Vida , Terapia por Exercício/métodos
3.
Sensors (Basel) ; 22(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35898083

RESUMO

The quality of the drinking water distributed through the networks has become the main concern of most operators. This work focuses on one of the most important variables of the drinking water distribution networks (WDN) that use disinfection, chlorine. This powerful disinfectant must be dosed carefully in order to reduce disinfection byproducts (DBPs). The literature demonstrates researchers' interest in modelling chlorine decay and using several different approaches. Nevertheless, the full-scale application of these models is far from being a reality in the supervision of water distribution networks. This paper combines the use of validated chlorine prediction models with an intensive study of a large amount of data and its influence on the model's parameters. These parameters are estimated and validated using data coming from the Supervisory Control and Data Acquisition (SCADA) software, a full-scale water distribution system, and using off-line analytics. The result is a powerful methodology for calibrating a chlorine decay model on-line which coherently evolves over time along with the significant variables that influence it.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Cloro/análise , Desinfecção , Purificação da Água/métodos
4.
Brain Imaging Behav ; 15(4): 2109-2120, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33048291

RESUMO

The link between literacy difficulties and brain alterations has been described in depth. Resting-state fMRI (rs-fMRI) has been successfully applied to the study of intrinsic functional connectivity (iFc) both in dyslexia and typically developing children. Most related studies have focused on the stages from late childhood into adulthood using a seed to voxel approach. Our study analyzes iFc in an early childhood sample using the multivariate pattern analysis. This facilitates a hypothesis-free analysis and the possible identification of abnormal functional connectivity patterns at a whole brain level. Thirty-four children with literacy difficulties (LD) (7.1 ± 0.69 yr.) and 30 typically developing children (TD) (7.43 ± 0.52 yr.) were selected. Functional brain connectivity was measured using an rs-fMRI acquisition. The LD group showed a higher iFc between the right middle frontal gyrus (rMFG) and the default mode network (DMN) regions, and a lower iFc between the rMFG and both the bilateral insular cortex and the supramarginal gyrus. These results are interpreted as a DMN on/off routine malfunction in the LD group, which suggests an alteration of the task control network regulating DMN activity. In the LD group, the posterior cingulate cortex also showed a lower iFc with both the middle temporal poles and the fusiform gyrus. This could be interpreted as a failure in the integration of information between brain regions that facilitate reading. Our results show that children with literacy difficulties have an altered functional connectivity in their reading and attentional networks at the beginning of the literacy acquisition. Future studies should evaluate whether or not these alterations could indicate a risk of developing dyslexia.


Assuntos
Dislexia , Alfabetização , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Criança , Pré-Escolar , Dislexia/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
5.
ChemSusChem ; 13(10): 2745-2752, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32108445

RESUMO

Cobalt complexes containing equatorial tetraazamacrocyclic ligands are active catalysts for the hydrogen evolution reaction in pure aqueous conditions. We investigated the effect of different groups directly linked to the macrocyclic ligand (-NH-, -NCH3 -, or -N(CH2 OH)-). In electrochemically induced hydrogen evolution catalysis at pH 4, the rate determining step is the protonation of the reduced CoI species that gives a cobalt hydride (CoIII -H), a key intermediate towards the H-H bond formation. In sharp contrast, under photochemical conditions using [Ru(bpy)3 ]2+ (bpy=2,2'-bipyridine) as a photosensitizer and ascorbate as sacrificial electron donor, the formation of a Co0 species that quickly protonates to give a CoII -H is proposed. In this scenario, the rate determining step is the H-H bond formation that occurs in an intermolecular fashion from the CoII -H species and a water molecule. Both mechanisms are supported by DFT calculations, which allowed us to estimate the pKa values of the CoIII -H and CoII -H species and transition states based on intramolecular and intermolecular H-H bond formation from CoII -H.

6.
Funct Neurol ; 29(3): 153-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25473734

RESUMO

Conventional cognitive assessment is based on a pencil-and-paper neuropsychological evaluation, which is time consuming, expensive and requires the involvement of several professionals. Information and communication technology could be exploited to allow the development of tools that are easy to use, reduce the amount of data processing, and provide controllable test conditions. Serious games (SGs) have the potential to be new and effective tools in the management and treatment of cognitive impairments Serious games for screening pre-dementia conditions: from virtuality to reality? A pilot project in the elderly. Moreover, by adopting SGs in 3D virtual reality settings, cognitive functions might be evaluated using tasks that simulate daily activities, increasing the "ecological validity" of the assessment. In this commentary we report our experience in the creation of the Smart Aging platform, a 3D SGand virtual environment-based platform for the early identification and characterization of mild cognitive impairment.


Assuntos
Disfunção Cognitiva/diagnóstico , Testes Neuropsicológicos , Interface Usuário-Computador , Jogos de Vídeo , Envelhecimento/psicologia , Humanos , Imageamento Tridimensional , Projetos Piloto , Reprodutibilidade dos Testes
7.
Comput Med Imaging Graph ; 37(4): 263-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23660135

RESUMO

We present as novel method for the exploration of multiple overlapping volumes that provides flexibility to merge data in different ways in different regions. In each region, either one of the modalities is rendered alone or the fusion of two modalities is shown. In the regions where data is fused, the relative weights of each modality are defined with a 2D transfer function depending on the voxel's pair of property values. The regions can be defined interactively by painting on the volume. Alternatively, when one of the modalities has been pre-classified, a graph representation of the dataset is constructed, and regions can be defined as sets of voxels fulfilling a specific combination of classification criteria. In both cases, a different fusion and shading function can be defined for each region. In this way, illustrative images of the dataset can be easily generated applying effects of cutting away, ghosting and modality enhancement.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Algoritmos , Animais , Aumento da Imagem/métodos , Reconhecimento Automatizado de Padrão/métodos , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...