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1.
BMC Infect Dis ; 24(1): 1051, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333907

RESUMO

The Hybrid NAR-RBFs Networks for COVID-19 fractional order model is examined in this scientific study. Hybrid NAR-RBFs Networks for COVID-19, that is more infectious which is appearing in numerous areas as people strive to stop the COVID-19 pandemic. It is crucial to figure out how to create strategies that would stop the spread of COVID-19 with a different age groups. We used the epidemic scenario in the Hybrid NAR-RBFs Networks as a case study in order to replicate the propagation of the modified COVID-19. In this research work, existence and stability are verified for COVID-19 as well as proved unique solutions by applying some results of fixed point theory. The developed approach to investigate the impact of Hybrid NAR-RBFs Networks due to COVID-19 at different age groups is relatively advanced. Also obtain solutions for a proposed model by utilizing Atanga Toufik technique and fractal fractional which are the advanced techniques for such type of infectious problems for continuous monitoring of spread of COVID-19 in different age groups. Comparisons has been made to check the efficiency of techniques as well as for finding the reliable solutions to understand the dynamical behavior of Hybrid NAR-RBFs Networks for non-linear COVID-19. Finally, the parameters are evaluated to see the impact of illness and present numerical simulations using Matlab to see actual behavior of this infectious disease for Hybrid NAR-RBFs Networks of COVID-19 for different age groups.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/transmissão , Humanos , Dinâmica não Linear , Pandemias
2.
Network ; : 1-53, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578214

RESUMO

This work chiefly explores fractional-order octonion-valued neural networks involving delays. We decompose the considered fractional-order delayed octonion-valued neural networks into equivalent real-valued systems via Cayley-Dickson construction. By virtue of Lipschitz condition, we prove that the solution of the considered fractional-order delayed octonion-valued neural networks exists and is unique. By constructing a fairish function, we confirm that the solution of the involved fractional-order delayed octonion-valued neural networks is bounded. Applying the stability theory and basic bifurcation knowledge of fractional order differential equations, we set up a sufficient condition remaining the stability behaviour and the appearance of Hopf bifurcation for the addressed fractional-order delayed octonion-valued neural networks. To illustrate the justifiability of the derived theoretical results clearly, we give the related simulation results to support these facts. Simultaneously, the bifurcation plots are also displayed. The established theoretical results in this work have important guiding significance in devising and improving neural networks.

3.
J Biol Phys ; 50(2): 149-179, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38157152

RESUMO

We present a mathematical model that explores the progression of Alzheimer's disease, with a particular focus on the involvement of disease-related proteins and astrocytes. Our model consists of a coupled system of differential equations that delineates the dynamics of amyloid beta plaques, amyloid beta protein, tau protein, and astrocytes. Amyloid beta plaques can be considered fibrils that depend on both the plaque size and time. We change our mathematical model to a temporal system by applying an integration operation with respect to the plaque size. Theoretical analysis including existence, uniqueness, positivity, and boundedness is performed in our model. We extend our mathematical model by adding two populations, namely prion protein and amyloid beta-prion complex. We characterize the system dynamics by locating biologically feasible steady states and their local stability analysis for both models. The characterization of the proposed model can help inform in advancing our understanding of the development of Alzheimer's disease as well as its complicated dynamics. We investigate the global stability analysis around the interior equilibrium point by constructing a suitable Lyapunov function. We validate our theoretical analysis with the aid of extensive numerical illustrations.


Assuntos
Doença de Alzheimer , Astrócitos , Modelos Biológicos , Príons , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Astrócitos/metabolismo , Príons/metabolismo , Humanos , Peptídeos beta-Amiloides/metabolismo , Proteínas tau/metabolismo
4.
Cogn Psychol ; 143: 101573, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37178616

RESUMO

Logico-semantic theories have long noted parallels between the linguistic representation of temporal entities (events) and spatial entities (objects): bounded (or telic) predicates such as fix a car resemble count nouns such as sandcastle because they are "atoms" that have well-defined boundaries, contain discrete minimal parts and cannot be divided arbitrarily. By contrast, unbounded (or atelic) phrases such as drive a car resemble mass nouns such as sand in that they are unspecified for atomic features. Here, we demonstrate for the first time the parallels in the perceptual-cognitive representation of events and objects even in entirely non-linguistic tasks. Specifically, after viewers form categories of bounded or unbounded events, they can extend the category to objects or substances respectively (Experiments 1 and 2). Furthermore, in a training study, people successfully learn event-to-object mappings that respect atomicity (i.e., grouping bounded events with objects and unbounded events with substances) but fail to acquire the opposite, atomicity-violating mappings (Experiment 3). Finally, viewers can spontaneously draw connections between events and objects without any prior training (Experiment 4). These striking similarities between the mental representation of events and objects have implications for current theories of event cognition, as well as the relationship between language and thought.


Assuntos
Cognição , Idioma , Humanos , Linguística , Semântica , Aprendizagem
5.
Math Comput Simul ; 203: 741-766, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35911951

RESUMO

The study explores the dynamics of a COVID-19 epidemic in multiple susceptible populations, including the various stages of vaccination administration. In the model, there are eight human compartments: completely susceptible; susceptible with dose-1 vaccination; susceptible with dose-2 vaccination; susceptible with booster dose vaccination; exposed; infected with and without symptoms, and recovered compartments. The biological feasibility of the model is analysed. The threshold value, R 0 , is derived using the next-generation matrix. The stability analysis of the equilibrium points was performed locally and globally using the threshold parameter of the model. The conditions determining disease persistence is obtained. The model is subjected to sensitivity analysis, and the most sensitive parameters are identified. Also, MATLAB is used to verify the mathematical outcomes of the system's dynamic behaviour and suggests that necessary steps should be taken to keep the spread of the omicron variant infectious disease under control. The findings of this study could aid health officials in their efforts to combat the spread of COVID-19.

6.
Entropy (Basel) ; 25(3)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36981291

RESUMO

This paper deals with the problems of finite-time boundedness (FTB) and H∞ FTB for time-delay Markovian jump systems with a partially unknown transition rate. First of all, sufficient conditions are provided, ensuring the FTB and H∞ FTB of systems given by linear matrix inequalities (LMIs). A new type of partially delay-dependent controller (PDDC) is designed so that the resulting closed-loop systems are finite-time bounded and satisfy a given H∞ disturbance attenuation level. The PDDC contains both non-time-delay and time-delay states, though not happening at the same time, which is related to the probability distribution of the Bernoulli variable. Furthermore, the PDDC is extended to two other cases; one does not contain the Bernoulli variable, and the other experiences a disordering phenomenon. Finally, three numerical examples are used to show the effectiveness of the proposed approaches.

7.
Entropy (Basel) ; 24(7)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35885172

RESUMO

This manuscript deals with the qualitative study of certain properties of an immunogenic tumors model. Mainly, we obtain a dynamically consistent discrete-time immunogenic tumors model using a nonstandard difference scheme. The existence of fixed points and their stability are discussed. It is shown that a continuous system experiences Hopf bifurcation at one and only one positive fixed point, whereas its discrete-time counterpart experiences Neimark-Sacker bifurcation at one and only one positive fixed point. It is shown that there is no chance of period-doubling bifurcation in our discrete-time system. Additionally, numerical simulations are carried out in support of our theoretical discussion.

8.
Math Comput Simul ; 179: 213-237, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32863550

RESUMO

The world of uncertainty motivates the study of stochastic perturbation in the mathematical models of real life. The main objective of this paper is to study stochastic sex-structured HIV/AIDS epidemic model with effect of screening of infectives. We have shown that the proposed stochastic epidemic model with boundedness and permanence has a unique global positive solution. The selection of suitable Lyapunov functions provides sufficient conditions for investigating persistence and extinction of disease. Based on numerical experiments, the theoretical findings of this paper have been verified.

9.
Entropy (Basel) ; 21(3)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33266966

RESUMO

In this paper, we researched some dynamical behaviors of a stochastic predator-prey system, which is considered under the combination of Crowley-Martin functional response and stage structure. First, we obtained the existence and uniqueness of the global positive solution of the system. Then, we studied the stochastically ultimate boundedness of the solution. Furthermore, we established two sufficient conditions, which are separately given to ensure the stochastic extinction of the prey and predator populations. In the end, we carried out the numerical simulations to explain some cases.

10.
Pflege ; 31(2): 87-99, 2018 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-29375003

RESUMO

Background: Local confinement and bedridden are important phenomena in nursing care. Nevertheless, conceptual definitions and appropriate nursing diagnoses are missing in the current nursing classification systems. Aim: The aim is to provide the basis for a conceptual definition. To this end, the current state of the German and English usage of the terms local confinement and bedridden are presented. At the same time, definitions of English-language terms, which are internationally widely recognized, are elaborated. Additionally, phenomena associated with local confinement and bedridden are recorded and delimited of each other. Method: The identification of the German and English conceptual usage takes place through an integrative literature review covering the period from 1990 to 2016. Results: There are a variety of English-language terms of location confinement and bedridden. The concepts of homebound, wheelchairbound and bedridden form of local confinement and bedridden most extensively. Instability, immobility is connected as cause and inactivity as a consequence. In contrast to this is bedrest, which is ordered and temporally limited. Conclusions: Local confinement and bedridden are to be viewed through the definition of boundedness. The antecedents (instability, immobility) must be diagnosed to derive adequate interventions to avoid or alleviate the consequences.


Assuntos
Pessoas Acamadas/classificação , Pessoas Acamadas/psicologia , Pacientes Domiciliares/classificação , Pacientes Domiciliares/psicologia , Diagnóstico de Enfermagem , Terminologia Padronizada em Enfermagem , Comparação Transcultural , Alemanha , Limitação da Mobilidade , Cadeiras de Rodas
11.
Appl Math Comput ; 256: 37-51, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25843986

RESUMO

Let [Formula: see text] be the open unit disk, [Formula: see text] an analytic self-map of [Formula: see text] and [Formula: see text] an analytic function on [Formula: see text]. Let D be the differentiation operator and [Formula: see text] the weighted composition operator. The boundedness and compactness of the product-type operator [Formula: see text] from the weighted Bergman-Orlicz space to the Bers type space, weighted Bloch space and weighted Zygmund space on [Formula: see text] are characterized.

12.
Cogn Sci ; 48(6): e13476, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38923020

RESUMO

What is the relationship between language and event cognition? Past work has suggested that linguistic/aspectual distinctions encoding the internal temporal profile of events map onto nonlinguistic event representations. Here, we use a novel visual detection task to directly test the hypothesis that processing telic versus atelic sentences (e.g., "Ebony folded a napkin in 10 seconds" vs. "Ebony did some folding for 10 seconds") can influence whether the very same visual event is processed as containing distinct temporal stages including a well-defined endpoint or lacking such structure, respectively. In two experiments, we show that processing (a)telicity in language shifts how people later construe the temporal structure of identical visual stimuli. We conclude that event construals are malleable representations that can align with the linguistic framing of events.


Assuntos
Idioma , Percepção Visual , Humanos , Masculino , Percepção Visual/fisiologia , Feminino , Cognição/fisiologia , Adulto Jovem , Compreensão/fisiologia , Adulto , Estimulação Luminosa
13.
AIMS Public Health ; 11(1): 19-35, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617407

RESUMO

Among women of reproductive age, PCOS (polycystic ovarian syndrome) is one of the most prevalent endocrine illnesses. In addition to decreasing female fertility, this condition raises the risk of cardiovascular disease, diabetes, dyslipidemia, obesity, psychiatric disorders and other illnesses. In this paper, we constructed a fractional order model for polycystic ovarian syndrome by using a novel approach with the memory effect of a fractional operator. The study population was divided into four groups for this reason: Women who are at risk for infertility, PCOS sufferers, infertile women receiving therapy (gonadotropin and clomiphene citrate), and improved infertile women. We derived the basic reproductive number, and by utilizing the Jacobian matrix and the Routh-Hurwitz stability criterion, it can be shown that the free and endemic equilibrium points are both locally stable. Using a two-step Lagrange polynomial, solutions were generated in the generalized form of the power law kernel in order to explore the influence of the fractional operator with numerical simulations, which shows the impact of the sickness on women due to the effect of different parameters involved.

14.
Adv Biol (Weinh) ; 8(4): e2300540, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311571

RESUMO

The aim of this study is to analyze and investigate the SARS-CoV-2 (SC-2) transmission with effect of heart attack in United Kingdom with advanced mathematical tools. Mathematical model is converted into fractional order with the help of fractal fractional operator (FFO). The proposed fractional order system is investigated qualitatively as well as quantitatively to identify its stable position. Local stability of the SC-2 system is verified and test the proposed system with flip bifurcation. Also system is investigated for global stability using Lyponove first and second derivative functions. The existence, boundedness, and positivity of the SC-2 is checked which are the key properties for such of type of epidemic problem to identify reliable findings. Effect of global derivative is demonstrated to verify its rate of effects of heart attack in united kingdom. Solutions for fractional order system are derived with the help of advanced tool FFO for different fractional values to verify the combine effect of COVID-19 and heart patients. Simulation are carried out to see symptomatic as well as a symptomatic effects of SC-2 in the United Kingdom as well as its global effects, also show the actual behavior of SC-2 which will be helpful to understand the outbreak of SC-2 for heart attack patients and to see its real behavior globally as well as helpful for future prediction and control strategies.


Assuntos
COVID-19 , Infarto do Miocárdio , Humanos , SARS-CoV-2 , Simulação por Computador , Surtos de Doenças
15.
Math Biosci Eng ; 21(1): 444-473, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303430

RESUMO

In this paper, we studied the stability of traveling wave solutions of a two-species Lotka-Volterra competition model in the form of a coupled system of reaction diffusion equations with nonlocal intraspecific and interspecific competitions in space at times. First, the uniform upper bounds for the solutions of the model was proved. By using the anti-weighted method and the energy estimates, the asymptotic stability of traveling waves with large wave speeds of the system was established.

16.
Sci Rep ; 14(1): 8058, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580678

RESUMO

In this paper, we propose a fractional-order mathematical model to explain the role of glucagon in maintaining the glucose level in the human body by using a generalised form of a fractal fractional operator. The existence, boundedness, and positivity of the results are constructed by fixed point theory and the Lipschitz condition for the biological feasibility of the system. Also, global stability analysis with Lyapunov's first derivative functions is treated. Numerical simulations for fractional-order systems are derived with the help of Lagrange interpolation under the Mittage-Leffler kernel. Results are derived for normal and type 1 diabetes at different initial conditions, which support the theoretical observations. These results play an important role in the glucose-insulin-glucagon system in the sense of a closed-loop design, which is helpful for the development of artificial pancreas to control diabetes in society.


Assuntos
Diabetes Mellitus Tipo 1 , Insulinas , Humanos , Glucagon , Diabetes Mellitus Tipo 1/tratamento farmacológico , Modelos Teóricos , Glucose
17.
Sci Rep ; 14(1): 10927, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740856

RESUMO

To study the dynamical system, it is necessary to formulate the mathematical model to understand the dynamics of various diseases which are spread in the world wide. The objective of the research study is to assess the early diagnosis and treatment of cholera virus by implementing remedial methods with and without the use of drugs. A mathematical model is built with the hypothesis of strengthening the immune system, and a ABC operator is employed to turn the model into a fractional-order model. A newly developed system SEIBR, which is examined both qualitatively and quantitatively to determine its stable position as well as the verification of flip bifurcation has been made for developed system. The local stability of this model has been explored concerning limited observations, a fundamental aspect of epidemic models. We have derived the reproductive number using next generation method, denoted as " R 0 ", to analyze its impact rate across various sub-compartments, which serves as a critical determinant of its community-wide transmission rate. The sensitivity analysis has been verified according to its each parameters to identify that how much rate of change of parameters are sensitive. Atangana-Toufik scheme is employed to find the solution for the developed system using different fractional values which is advanced tool for reliable bounded solution. Also the error analysis has been made for developed scheme. Simulations have been made to see the real behavior and effects of cholera disease with early detection and treatment by implementing remedial methods without the use of drugs in the community. Also identify the real situation the spread of cholera disease after implementing remedial methods with and without the use of drugs. Such type of investigation will be useful to investigate the spread of virus as well as helpful in developing control strategies from our justified outcomes.


Assuntos
Cólera , Modelos Teóricos , Cólera/epidemiologia , Humanos , Epidemias/prevenção & controle , Simulação por Computador
18.
ISA Trans ; 146: 114-126, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38160076

RESUMO

In the set-point following, the asymptotic property of the stability would disappear in the presence of time-varying references and disturbances. Hence, the boundedness of state variables is an essential issue in the regulation. To this aim, in light of time-varying references and disturbed signals, a robust integral policy is systematically developed to achieve the control aim in the uncertain equations with delay. Utilizing linear matrix inequality, a guideline is suggested for guaranteeing the boundedness of the solutions in uncertain systems with delays. Then, the gains of the control law are computed from a minimization. Although the boundedness is ultimately obtained in the perturbed case, the asymptotic stability would also be deduced for the nominal systems. The findings are numerically evaluated in some simulations. The favorability of the proposed integral method is shown in comparison to the traditional control strategies.

19.
Sci Rep ; 14(1): 16257, 2024 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009619

RESUMO

In order to comprehend the dynamics of disease propagation within a society, mathematical formulations are essential. The purpose of this work is to investigate the diagnosis and treatment of lung cancer in persons with weakened immune systems by introducing cytokines ( I L 2 & I L 12 ) and anti-PD-L1 inhibitors. To find the stable position of a recently built system TCD I L 2 I L 12 Z, a qualitative and quantitative analysis are taken under sensitive parameters. Reliable bounded findings are ensured by examining the generated system's boundedness, positivity, uniqueness, and local stability analysis, which are the crucial characteristics of epidemic models. The positive solutions with linear growth are shown to be verified by the global derivative, and the rate of impact across every sub-compartment is determined using Lipschitz criteria. Using Lyapunov functions with first derivative, the system's global stability is examined in order to evaluate the combined effects of cytokines and anti-PD-L1 inhibitors on people with weakened immune systems. Reliability is achieved by employing the Mittag-Leffler kernel in conjunction with a fractal-fractional operator because FFO provide continuous monitoring of lung cancer in multidimensional way. The symptomatic and asymptomatic effects of lung cancer sickness are investigated using simulations in order to validate the relationship between anti-PD-L1 inhibitors, cytokines, and the immune system. Also, identify the actual state of lung cancer control with early diagnosis and therapy by introducing cytokines and anti-PD-L1 inhibitors, which aid in the patients' production of anti-cancer cells. Investigating the transmission of illness and creating control methods based on our validated results will both benefit from this kind of research.


Assuntos
Antígeno B7-H1 , Linfócitos T CD8-Positivos , Neoplasias Pulmonares , Humanos , Linfócitos T CD8-Positivos/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Citocinas/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Simulação por Computador
20.
Math Biosci Eng ; 21(5): 6097-6122, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38872571

RESUMO

In this work, we investigated the finite-time passivity problem of neutral-type complex-valued neural networks with time-varying delays. On the basis of the Lyapunov functional, Wirtinger-type inequality technique, and linear matrix inequalities (LMIs) approach, new sufficient conditions were derived to ensure the finite-time boundedness (FTB) and finite-time passivity (FTP) of the concerned network model. At last, two numerical examples with simulations were presented to demonstrate the validity of our criteria.

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