Leonardo Abdala Elias

@article{Viviani2025,

title = {Design and usability assessment of touchscreen interface in medical devices: a case study of a neonatal incubator},

author = {Carlos Alessandro Bassi Viviani and Leonardo Abdala Elias and Saide Jorge Calil},

doi = {10.1007/s42600-025-00401-x},

issn = {2446-4740},

year  = {2025},

date = {2025-03-00},

journal = {Res. Biomed. Eng.},

volume = {41},

number = {1},

publisher = {Springer Science and Business Media LLC},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid35696826,

title = {Effects of light finger touch on the regularity of center-of-pressure fluctuations during quiet bipedal and single-leg postural tasks},

author = {Jéssica Rodrigues Lara and Cristiano Rocha da Silva and Felipe Fava de Lima and Marcos Camargo da Silva and André Fabio Kohn and Leonardo Abdala Elias and Fernando Henrique Magalhães},

doi = {10.1016/j.gaitpost.2022.05.036},

issn = {1879-2219},

year  = {2022},

date = {2022-07-01},

journal = {Gait Posture},

volume = {96},

pages = {203--209},

abstract = {BACKGROUND: The use of extra sources of sensory information associated with light fingertip touch to enhance postural steadiness has been associated with increased attentional demands, whereas the regularity of center of pressure (COP) fluctuations has been interpreted as a marker of the amount of attention invested in posture control.



RESEARCH QUESTION: This study addressed whether increased attentional demands associated with postural tasks involving light finger touch might be reflected by measures of COP regularity.



METHODS: The experiments involved quiet bipedal stance (n = 8 participants) and single-legged stance (n = 14 participants). Each participant was instructed to stand as quietly as possible on a force plate, either touching an external rigid surface (applied force < 1 N, light touch condition), or not (no touch condition). Postural steadiness was assessed by traditional COP measurements (COP Area, RMS, and velocity), whereas the regularity of postural sway was based on estimates of the sample entropy (SaEn) of the COP time series.



RESULTS: Traditional parameters of postural sway and COP regularity (inversely related to SaEn COP measurements) were reduced during the touch conditions as compared to the no-touch conditions, for both bipedal quiet stance and single-legged stance. Decreased COP regularity with light touch was mainly reflected in the direction of the largest postural sway (i.e. in the sagittal plane for bipedal stance and in the frontal plane for single-legged stance).



SIGNIFICANCE: The present results suggest that actively touching an external surface with the fingertip, besides increasing postural steadiness, generated an externally oriented (presumably cognitive-dependent) focus of attention, so that participants invested less attention on the postural task per se (as suggested by increased SaEn), which might be associated with a more "automatic" control of posture.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid34802707,

title = {Influence of central and peripheral motor unit properties on isometric muscle force entropy: A computer simulation study},

author = {Jakob Dideriksen and Leonardo Abdala Elias and Ellen Pereira Zambalde and Carina Marconi Germer and Ricardo Gonçalves Molinari and Francesco Negro},

doi = {10.1016/j.jbiomech.2021.110866},

issn = {1873-2380},

year  = {2022},

date = {2022-06-01},

journal = {J Biomech},

volume = {139},

pages = {110866},

abstract = {Approximate entropy of isometric force is a popular measure to characterize behavioral changes across muscle contraction conditions. The degree to which force entropy characterizes the randomness of the motor control strategy, however, is not known. In this study, we used a computational model to investigate the correlation between approximate entropy of the synaptic input to a motor neuron pool, the neural drive to muscle (cumulative spike train; CST), and the force. This comparison was made across several simulation conditions, that included different synaptic command signal bandwidths, motor neuron pool sizes, and muscle contractile properties. The results indicated that although force entropy to some degree reflects the entropy of the synaptic command to motor neurons, it is biased by changes in motor unit properties. As a consequence, there was a low correlation between approximate entropy of force and the motor neuron input signal across all simulation conditions (r = 0.13). Therefore, force entropy should only be used to compare motor control strategies across conditions where motor neuron properties can be assumed to be maintained. Instead, we recommend that the entropy of the descending motor commands should be estimated from CSTs comprising spike trains of multiple motor units.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {A Case Study on the Removal of Blinking Artifact in Electroencephalogram Signals via Stochastic Filtering},

author = {Rebecca Fernandes Ribeiro and Victor Baptista Frencl and Leonardo Abdala Elias and João Bosco Ribeiro do Val },

doi = {https://doi.org/10.1007/s40313-021-00890-y},

year  = {2022},

date = {2022-01-12},

journal = {Journal of Control, Automation and Electrical Systems},

volume = {33},

pages = {1319–1328},

abstract = {The presence of physiological artifacts in electroencephalogram (EEG) signals is common and detrimental to experimental or clinical analysis. This paper presents a case study where we develop an algorithm based on stochastic filtering to remove blinking artifacts. For this case study, the dynamic system was defined by combining two autoregressive models, the first one represents the EEG signal, and the second one represents the blinking artifact. Some applications use stochastic methods to remove artifacts, so in this paper we apply the stochastic filtering via Kalman filter, that makes possible to remove blinking artifacts from single-channel EEG recordings, as long as the electrooculogram (EOG) signal was available. The method applies to a case study with actual artifacts and simulated artifacts for comparison. The measure of performance utilized is the estimated power spectral density (PSD). The results show that the proposed method could remove blinking artifacts without introducing significant distortions in the EEG signal.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid35646854,

title = {High-Resolution Magic-Angle Spinning NMR Spectroscopy for Evaluation of Cell Shielding by Virucidal Composites Based on Biogenic Silver Nanoparticles, Flexible Cellulose Nanofibers and Graphene Oxide},

author = {Danijela Stanisic and Guilherme C F Cruz and Leonardo Abdala Elias and Junko Tsukamoto and Clarice W Arns and Douglas Soares da Silva and Stanislav Mochkalev and Raluca Savu and Ljubica Tasic},

doi = {10.3389/fbioe.2022.858156},

issn = {2296-4185},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Front Bioeng Biotechnol},

volume = {10},

pages = {858156},

abstract = {Antiviral and non-toxic effects of silver nanoparticles onto  cells infected with coronavirus were evaluated in this study using High-Resolution Magic-Angle Spinning Nuclear Magnetic Resonance (HR-MAS NMR) spectroscopy. Silver nanoparticles were designed and synthesized using an orange flavonoid-hesperetin (HST)-for reduction of silver(I) and stabilization of as obtained nanoparticles. The bio-inspired process is a simple, clean, and sustainable way to synthesize biogenic silver nanoparticles (AgNP@HST) with diameters of ∼20 nm and low zeta potential (-40 mV), with great colloidal stability monitored for 2 years. The nanoparticles were used for the fabrication of two types of antiviral materials: colloids (AgNP@HST spray) and 3D flexible nanostructured composites. The composites, decorated with AgNP@HST (0.05 mmol L), were made using cellulose nanofibers (CNF) obtained from orange peel and graphene oxide (GO), being denominated CNF@GO@AgNP@HST. Both materials showed high virucidal activity against coronaviruses in cell infection  models and successfully inhibited the viral activity in cells. HR-MAS H-NMR technique was used for determining nanomaterials' effects on living cells and their influences on metabolic pathways, as well as to study viral effects on cells. It was proven that none of the manufactured materials showed toxicity towards the intact cells used. Furthermore, viral infection was reverted when cells, infected with the coronavirus, were treated using the as-fabricated nanomaterials. These significant results open possibilities for antiviral application of 3D flexible nanostructured composite such as packaging papers and filters for facial masks, while the colloidal AgNP@HST spray can be used for disinfecting surfaces, as well as a nasal, mouth, and eye spray.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}