195 documents found, page 1 of 20
Factorization à la Dirac applied to the time-fractional telegraph equation
Ferreira, M.; Rodrigues, M.M.; Vieira, N.This paper examines a coupled system of two-term time-fractional diffusion Dirac-type equations. The system is derived by factorizing the multi-dimensional time-fractional telegraph equation with Hilfer fractional derivatives, using the Dirac method and a triplet of Pauli matrices. Solutions are obtained using operational methods provided by the combination of the Fourier transform in the space variable and the...
The Relevance of Hand Mobility and Functionality Surveillance in Patients with ...
Madureira, N.; Carvalho, C.; Pereira, A.; Xavier, M.; Sousa, J.; Martins, S.; Soares, C.; Ferreira, M.; Guimarães, F.; Santos-Faria, D.Introduction: Systemic sclerosis causes skin thickening, Raynaud’s phenomenon, visceral damage, and musculoskeletal issues. Hand impairment, affecting about 90% of patients, limits mobility, dexterity, and grip strength, significantly impacting daily life, with few treatment options. This study aims to characterize hand function in patients with Systemic Sclerosis and, secondarily, to describe those undergoing ...
In vivo activity of peptide-ionic liquid conjugates against diabetic wounds
Gomes, A.; Ferraz, Ricardo; Ferreira, M.; Maciel, J.; Plácido, A.; Leal, E.; Gameiro, P.; Gonçalves, Teresa; Carvalho, E.; Gomes, P.Due to widespread multidrug-resistant (MDR) microbes, efficient treatments for infected wounds are being exhausted, which means that there is an alarming lack of effective antibiotics to treat diabetic foot ulcers (DFU). The increasing life expectancy of the population and the growing incidence of unhealthy lifestyles is leading to a concerning rise in the number of people affected with diabetes and related com...
Youth-caregiver relationship quality in residential youth care: Professionals’ ...
Magalhães, E.; Ferreira, M.; Ornelas, S.; Silva, C. S.; Camilo, C.; Calheiros, M. M.This study aimed to explore the perceptions and experiences of professionals working in residential care (RC) settings (i.e., caregivers and directors) about youth-caregiver relationship quality (YCRQ). Method: A qualitative study was developed in Portugal including 15 caregivers (73.3% women, 23–50 years) and 15 directors (73.3% women, 34–45 years) working in 18 generalist RC units. Data were collected through...
Dirac's method applied to the time-fractional diffusion-wave equation
Ferreira, M.; Vieira, N.; Rodrigues, M. M.We compute the fundamental solution for time-fractional diffusion Dirac-like equations, which arise from the factorization of the multidimensional time-fractional diffusion-wave equation using Dirac's factorization approach.
Distributed-order relaxation-oscillation equation
Rodrigues, M. M.; Ferreira, M.; Vieira, N.In this short paper, we study the Cauchy problem associated with the forced time-fractional relaxation-oscillation equation with distributed order. We employ the Laplace transform technique to derive the solution. Additionally, for the scenario without external forcing, we focus on density functions characterized by a single order, demonstrating that under these conditions, the solution can be expressed using t...
Hypercomplex operator calculus for the fractional Helmholtz equation
Vieira, N.; Ferreira, M.; Rodrigues, M. M.; Kraußhar, R. S.In this paper, we develop a hypercomplex operator calculus to treat fully analytically boundary value problems for the homogeneous and inhomogeneous fractional Helmholtz equations where fractional derivatives in the sense of Caputo and Riemann-Liouville are applied. Our method extends the recently proposed Fractional Reduced Differential Transform Method (FRDTM) by using fractional derivatives in all directions...
Out of sight is not out of mind: Associations between perceived maternal attach...
Ferreira, M.; Calheiros, M. M.; Silva, C. S.; Magalhães, E.The present study aimed to explore the associations between perceived maternal attachment and self-representations of youth in residential care (RC), considering the potential moderator role of youth’s sex and age and the potential concurrent effect of frequency and type of family visits and length of time in RC. To this end, a sample of 659 youth aged 11–18 (M = 15.65, SD = 1.72) from RC settings filled out se...
The Teodorescu and the Π-operator in octonionic analysis and some applications
Kraußhar, R. S.; Ferreira, M.; Vieira, N.; Rodrigues, M. M.In the development of function theory in octonions, the non-associativity property produces an additional associator term when applying the Stokes formula. To take the non-associativity into account, particular intrinsic weight factors are implemented in the definition of octonion-valued inner products to ensure the existence of a reproducing Bergman kernel. This Bergman projection plays a pivotal role in the $...
Quaternion Hyperbolic Fourier Transforms and uncertainty principles
Ferreira, M.; Morais, J.The present study introduces the two-sided and right-sided Quaternion Hyperbolic Fourier Transforms (QHFTs) for analyzing two-dimensional qua\-ternion-valued signals defined in an open rectangle of the Euclidean plane endowed with a hyperbolic measure. The different forms of these transforms are defined by replacing the Euclidean plane waves with the corresponding hyperbolic plane waves in one dimension, giving...