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1.
Neural Netw ; 175: 106273, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38569459

ABSTRACT

Big torque inputs in controls could increase energy consumption, and big estimated perturbations in observers could produce device damages. Therefore, it would be interesting to propose a constrained control for safe reference tracking and a constrained observer for safe perturbation estimation in robots. Furthermore, the best gains in controls produce a balance between safe reference tracking and save energy consumption. Therefore, it would be interesting to propose a method to find the best gains. In this paper, an observer-based differential evolution constrained control is proposed for safe reference tracking in robots. The contributions are described as follows: (1) a constrained observer is proposed for safe perturbation estimation in robots, (2) a constrained control is proposed for safe reference tracking in robots, (3) a differential evolution optimizer is used to find the best gains in an observer-based constrained control, (4) the robust stability in an observer-based constrained control is assured, (5) the pseudo-code of an observer-based differential evolution constrained control is detailed. The proposed observer-based differential evolution constrained control is applied for safe reference tracking in two robots.


Subject(s)
Neural Networks, Computer , Robotics , Algorithms , Humans , Torque
2.
Enferm. clín. (Ed. impr.) ; 34(1): 61-73, Ene-Feb, 2024. ilus, tab, graf
Article in Spanish | IBECS | ID: ibc-229658

ABSTRACT

Objetivo: Realizar una revisión de la literatura para analizar si la estimulación de puntos de acupuntura aumenta la cantidad de leche producida durante la lactancia. Método: Se recopilaron estudios de cinco bases de datos electrónicas siguiendo las recomendaciones internacionales para la elaboración de revisiones sistemáticas y metaanálisis. Los criterios de elegibilidad fueron artículos de texto completo en inglés o español con diseño de ensayos clínicos y estudios observacionales, sin restricción en el tiempo de publicación, en los cuales se hubiera evaluado el efecto de la estimulación de puntos de acupuntura en la mejora de la cantidad de lactancia mediante acupuntura convencional, electroacupuntura, láser, agujas de fuego, estimulación manual, Tui Na o catgut. Dos autores extrajeron de forma independiente los datos de las características y los resultados principales de los estudios seleccionados para su inclusión. Se realizaron las evaluaciones de riesgo de sesgo y de calidad (GRADE). Para la síntesis cuantitativa se calculó la diferencia de medias estandarizada para cada estudio individual seleccionado y luego se combinaron los datos mediante un metaanálisis de efectos aleatorios. Resultados: En la presente revisión se incluyeron un total de 14 estudios, la mayoría de ellos mostraron riesgo de sesgo y una calidad moderada. El metaanálisis mostró que la estimulación manual del punto de acupuntura aumenta la cantidad de leche materna (DME 95% IC=1,63 [1,13-2,13]; p<0,0001). Conclusión: La literatura sugiere que la estimulación manual de puntos de acupuntura mejora la cantidad de leche producida durante de lactancia.(AU)


Objective: To perform a literature review aimed to analyze if acupoint stimulation increases lactation quantity. Method: Studies were collected from five electronic databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews. Eligibility criteria were full-text articles in English or Spanish with clinical trial design and observational studies, with no restriction on time of publication, in which the effect of acupoint stimulation on improving the quantity of lactation by conventional acupuncture, electroacupuncture, laser, fire needling, manual stimulation, tuina or catgut had been evaluated. Two authors independently extracted data for the characteristics and main outcomes of the studies selected for inclusion. The risk of bias (RoB 2 and Robins-I) and the quality assessments (GRADE) were performed. For the quantitative synthesis, the standardized mean difference was calculated for each individual study selected and then the data were combined using a random-effects meta-analysis. Results: A total of 14 studies were included in the present review. Most of the included studies exhibited some concerns in the risk of bias assessment. The quality of the studies was moderate. The meta-analysis showed that manual acupoint stimulation improves the lactation quantity (SMD 95% CI=1.63 [1.13-2.13]; p<0.0001). Conclusion: The literature suggests that manual stimulation of acupuncture points improves the amount of milk produced during lactation.(AU)


Subject(s)
Humans , Female , Lactation Disorders/drug therapy , Breast Feeding , Acupuncture Therapy , Acupuncture Points
3.
Enferm Clin (Engl Ed) ; 34(1): 61-73, 2024.
Article in English | MEDLINE | ID: mdl-38185370

ABSTRACT

OBJECTIVE: To perform a literature review aimed to analyze if acupoint stimulation increases lactation quantity. METHOD: Studies were collected from five electronic databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews. Eligibility criteria were full-text articles in English or Spanish with clinical trial design and observational studies, with no restriction on time of publication, in which the effect of acupoint stimulation on improving the quantity of lactation by conventional acupuncture, electroacupuncture, laser, fire needling, manual stimulation, tuina or catgut had been evaluated. Two authors independently extracted data for the characteristics and main outcomes of the studies selected for inclusion. The risk of bias (RoB 2 and Robins-I) and the quality assessments (GRADE) were performed. For the quantitative synthesis, the standardized mean difference was calculated for each individual study selected and then the data were combined using a random-effects meta-analysis. RESULTS: A total of 14 studies were included in the present review. Most of the included studies exhibited some concerns in the risk of bias assessment. The quality of the studies was moderate. The meta-analysis showed that manual acupoint stimulation improves the lactation quantity (SMD 95% CI = 1.63 [1.13-2.13]; p < 0.0001). CONCLUSION: The literature suggests that manual stimulation of acupuncture points improves the amount of milk produced during lactation.


Subject(s)
Acupuncture Therapy , Lactation Disorders , Female , Humans , Acupuncture Points
4.
Med. oral patol. oral cir. bucal (Internet) ; 29(1): e9-e17, Ene. 2024. tab, ilus
Article in English | IBECS | ID: ibc-229183

ABSTRACT

Background: Chitosan is a cheap, accessible, nontoxic, biocompatible, and biodegradable compound. Also, thispolysaccharide possesses antibacterial and anti-inflammatory properties. Consequently, a wide range of chitosanapplications in the dentistry field has been explored. This work aimed to conduct a systematic review to addressthe clinical efficacy of chitosan for the treatment of oral mucositis.Material and Methods: The design of the included studies were observational studies, randomized clinical trials(RCT), and non-randomized clinical trials (non-RCT), whereas, a series of cases, in vivo, and in vitro studies wereexcluded. The search was performed in PubMed, Web of Science, Scopus, Dentistry and Oral Sciences Source,and ClinicalTrials. Gray literature was searched at Google Scholar. Relevant data from all included studies wererecorded. The risk of bias (using RoB 2) and the quality (using Grading of Recommendations Assessment, Devel-opment, and Evaluation, GRADE) assessments were carried out.Results: From the 8413 records screened, 5 clinical trials fully met the eligibility criteria, which comprised a totalof 192 participants suffering oral lesions and pain related to oral mucositis. 100% of the included studies exhibiteda high risk of bias. The quality of the studies was between low and very low.Conclusions: The results of the included studies suggest that chitosan can diminish pain and improve the healingof ulcers in oral mucositis. However, there is no conclusive evidence of chitosan as a superior treatment for oralmucositis compared with other current therapies.(AU)


Subject(s)
Humans , Male , Female , Wound Healing , Chitosan , Inflammation/drug therapy , Mouth Mucosa , Chitosan/therapeutic use , Pain/drug therapy , Mouth Diseases , Oral Health , Dentistry , Oral Medicine
5.
Neural Netw ; 170: 32-45, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37972455

ABSTRACT

From the control theory, bigger observer and controller gains are utilized to improve the position perturbation attenuation, while smaller observer and controller gains are utilized to improve the velocity perturbation attenuation. Therefore, it would be interesting to suggest optimizers to find the best observer and controller gains to improve the position or velocity perturbation attenuation. In this investigation, a high-gain controller is suggested to obtain the perturbation attenuation, a genetic high-gain controller is suggested to improve the position perturbation attenuation, and a compact high-gain controller is suggested to improve velocity perturbation attenuation in inverted pendulums. The high-gain controller utilizes a high-gain observer and a high-gain estimator to obtain the state and perturbation estimation. The genetic high-gain controller utilizes a genetic optimizer to find the best observer and controller gains. The compact high-gain controller utilizes a compact optimizer to find the best observer and controller gains. The suggested high-gain controllers are compared with the simplex and bat controllers to improve the position or velocity perturbation attenuation in two inverted pendulums.

6.
Biomimetics (Basel) ; 7(4)2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36546911

ABSTRACT

Recently, biomimetic bioactive biomaterials have been introduced to the market for dental pulp capping. This systematic review and meta-analysis aimed to determine any variation between the effect of using TheraCal LC and other bioactive biomaterials for pulp capping is different, as measured by dentin increment and clinical success. The risk of bias was assessed using the Risk of Bias 2 and Newcastle−Ottawa tools for randomized clinical trials and observational studies. A search for relevant articles was performed on five databases. Additionally, the quality of the included studies was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. A summary of individual studies and a meta-analysis were performed. The odds ratio of data from clinical success was combined using a random-effects meta-analysis. The meta-analysis results showed homogeneity between the studies (I2 = 0%). They revealed that the clinical success showed no differences between the patients who received TheraCal LC, light-cured calcium silicate-based biomimetic biomaterial, for dental pulp capping or the comparator biomaterials (p > 0.5). However, the certainty of the evidence was low to moderate due to the risk of bias in the included studies.

7.
Antibiotics (Basel) ; 11(9)2022 Aug 25.
Article in English | MEDLINE | ID: mdl-36139930

ABSTRACT

Nowadays, the increase in bacteria resistant to multiple antibiotics has become a real threat to the human health, forcing researchers to develop new strategies. Silver nanoparticles (AgNPs) may be a viable solution to this problem. The green synthesis of AgNPs is considered a green, ecological and low-priced process that provides small and biocompatible nanostructures with antimicrobial activity with a potential application in medicine. In this work, pecan nut shell extracts were analyzed in order to determine their viability for the production of AgNPs. These NPs were synthesized using an extract rich in bioactive molecules, varying the reaction time and silver nitrate (AgNO3) concentration. AgNPs production was confirmed by FT-IR, UV-Vis and EDX spectroscopy, while their morphology and size were determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The antibacterial activity of AgNPs was evaluated by the agar diffusion method against Salmonella typhi, Staphylococcus aureus and Proteus mirabilis. The results showed that it is possible to obtain nanoparticles from an extract rich in antioxidant molecules with a size between 39.9 and 98.3 nm with a semi-spherical morphology. In addition, it was shown that the reaction time and the concentration of the precursor influence the final nanoparticles size. Antimicrobial tests showed that there is greater antimicrobial inhibition against Gram-negative than Gram-positive microorganisms, obtaining inhibition zone from 0.67 to 5.67 mm.

8.
Heliyon ; 6(11): e05418, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33225088

ABSTRACT

During the phenomena modelling process in the different areas of science and engineering is common to face nonlinear equations without exact solutions; thus, the need of employing numerical methods to obtain such solutions. Therefore, in order to provide new possibilities for the isolation of variables, we propose a novel family of transcendental functions with new algebraic properties including their integration and differentiation rules. Likewise, in order facilitate the numerical evaluation for every new family set of functions, a highly accurate series of approximations is proposed by employing analytical expressions in terms of known transcendental functions and polynomials combinations. By the use of known functions for the proposed approximations, makes possible the use of any programming language for their respective implementation. In this article, three interesting case studies are presented with applications on: coastal engineering, transmission lines span on electrical engineering, and the planar one-dimensional Bratu equation. Finally, based on the results from study cases, it can be concluded that Leal-functions will have relevant impact in all areas of physics and mathematics, by providing new tools to scientists and engineers for the proposal of new mathematical models and numerical/analytical analysis, design and implementation of new theories and technological innovations.

9.
Heliyon ; 6(4): e03695, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32322709

ABSTRACT

This work presents the novel Leal-polynomials (LP) for the approximation of nonlinear differential equations of different kind. The main characteristic of LPs is that they satisfy multiple expansion points and its derivatives as a mechanism to replicate behaviour of the nonlinear problem, giving more accuracy within the region of interest. Therefore, the main contribution of this work is that LP satisfies the successive derivatives in some specific points, resulting more accurate polynomials than Taylor expansion does for the same degree of their respective polynomials. Such characteristic makes of LPs a handy and powerful tool to approximate different kind of differential equations including: singular problems, initial condition and boundary-valued problems, equations with discontinuities, coupled differential equations, high-order equations, among others. Additionally, we show how the process to obtain the polynomials is straightforward and simple to implement; generating a compact, and easy to compute, expression. Even more, we present the process to approximate Gelfand's equation, an equation of an isothermal reaction, a model for chronic myelogenous leukemia, Thomas-Fermi equation, and a high order nonlinear differential equations with discontinuities getting, as result, accurate, fast and compact approximate solutions. In addition, we present the computational convergence and error studies for LPs resulting convergent polynomials and error tendency to zero as the order of LPs increases for all study cases. Finally, a study of CPU time shows that LPs require a few nano-seconds to be evaluated, which makes them suitable for intensive computing applications.

10.
CienciaUAT ; 13(2): 6-17, ene.-jun. 2019. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1011772

ABSTRACT

RESUMEN El campo de las ecuaciones diferenciales ha cobrado auge en la actualidad por el desarrollo científico y tecnológico. Por esta situación, el estudio de nuevas metodologías para solucionarlas se ha vuelto importante. A partir de la combinación del método de Laplace Transform (LT) y el método de perturbación (PM) este trabajo presenta el método LT-PM, y su motivación se encuentra en la aplicación conocida de la LT a ecuaciones diferenciales ordinarias lineales. El objetivo de este trabajo fue presentar una modificación del método de perturbación (PM), el método de perturbación con transformada de Laplace (LT-PM), con el fin de resolver problemas perturbativos no lineales, con condiciones a la frontera definidas en intervalos finitos. La metodología consistió en aplicar LT a la ecuación diferencial por resolver y después de asumir que la solución de la misma se puede expresar como una serie de potencias de un parámetro perturbativo, se obtiene la solución del problema aplicando sistemáticamente la transformada inversa de Laplace. Los principales resultados de este trabajo se muestran a partir de dos casos de estudio presentados, donde se observa que LT-PM es potencialmente útil para encontrar soluciones múltiples de problemas no lineales. Además, LT-PM mejora la aplicabilidad del método de perturbación en algunos casos de condiciones a la frontera mixtas y de Neumann, donde PM simplemente no funciona. Con el fin de verificar la exactitud de los resultados obtenidos, se calculó su error residual cuadrático (SRE), el cual resultó muy bajo, de donde se dedujo su precisión y la potencialidad de LT-PM. Se concluye que si bien el método propuesto resulta eficiente en los casos particulares presentados, se espera que sea una herramienta potencialmente eficiente y útil para otros casos de estudio, particularmente, en aquellos relacionados con aplicaciones prácticas en ciencias e ingeniería.


ABSTRACT The field of differential equations has recently gained attention due to recent developments in science and technology. For this reason, the analysis for the use of new methodologies to solve them has become important. Based on the combination of Laplace Transform method (LT) and Perturbation Method (PM) this article pro- poses the Laplace transform-Perturbation Method (LT-PM) which finds its motivation on the application of LT to linear ordinary differential equations. The goal of this work is to propose a modification of PM - the LT-PM), in order to solve nonlinear perturbative problems with boundary conditions defined on finite intervals. The proposed methodology consisted on the application of LT to the differential equation to solve and then, assuming that its solutions can be expressed as a series of perturbative parameter powers. Thus, the solution of the problem is obtained by systematically applying the transformed inverse LT. The main results of this paper were shown through two case studies, where LT-PM is identified as potentially useful for finding multiple solutions to nonlinear problems. Additionally, the LT-PM enhances the applicability of PM, in some cases of mixed and Neumann boundary conditions, where PM is unsuitable to provide the results. With the purpose of verifying the accuracy of the obtained results, the Square Residual Error (SRE) was calculated. The resulting value was extremely low, which showed the precision and potential of LT-PM. We conclude that, although the proposed method resulted efficient for the case studies presented in this article, it is expected that LT-PM can be a potentially useful tool for other case studies. Particularly those related to the practical applications of science and engineering.

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