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1.
Sensors (Basel) ; 24(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38894473

RESUMO

Sign language is an essential means of communication for individuals with hearing disabilities. However, there is a significant shortage of sign language interpreters in some languages, especially in Saudi Arabia. This shortage results in a large proportion of the hearing-impaired population being deprived of services, especially in public places. This paper aims to address this gap in accessibility by leveraging technology to develop systems capable of recognizing Arabic Sign Language (ArSL) using deep learning techniques. In this paper, we propose a hybrid model to capture the spatio-temporal aspects of sign language (i.e., letters and words). The hybrid model consists of a Convolutional Neural Network (CNN) classifier to extract spatial features from sign language data and a Long Short-Term Memory (LSTM) classifier to extract spatial and temporal characteristics to handle sequential data (i.e., hand movements). To demonstrate the feasibility of our proposed hybrid model, we created a dataset of 20 different words, resulting in 4000 images for ArSL: 10 static gesture words and 500 videos for 10 dynamic gesture words. Our proposed hybrid model demonstrates promising performance, with the CNN and LSTM classifiers achieving accuracy rates of 94.40% and 82.70%, respectively. These results indicate that our approach can significantly enhance communication accessibility for the hearing-impaired community in Saudi Arabia. Thus, this paper represents a major step toward promoting inclusivity and improving the quality of life for the hearing impaired.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Língua de Sinais , Humanos , Arábia Saudita , Idioma , Gestos
2.
Cureus ; 16(4): e57842, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38721162

RESUMO

BACKGROUND: Systemic Lupus Erythematosus (SLE) is an autoimmune inflammatory condition affecting multiple systems. Cardiovascular morbidity is a significant concern, with around 25% of SLE patients experiencing cardiac complications. OBJECTIVE: This study aims to determine the prevalence of cardiovascular morbidity in SLE patients in King Fahad Medical City (KFMC) in Riyadh, Saudi Arabia. METHODOLOGY: This retrospective record-based research was conducted at KFMC from January 2015 to October 2023. A review of the medical files of all SLE patients was accomplished. RESULTS: The vast majority of the patients (90.9%) were females. The mean age for the patients was 36.5 years. The most common comorbidities were lupus nephritis (34.6%), hypothyroidism (18.4%), and anti-phospholipid syndrome (9.2%). The most commonly used medications were hydroxychloroquine (81.8%), corticosteroids (prednisolone) (43.0%), and mycophenolate mofetil (27.9%). Around 45.2% (n= 176) of the patients with SLE developed cardiovascular complications. The most commonly reported cardiovascular diseases that developed after diagnosing patients with SLE were hypertension (22.4%), valvular heart diseases (13.2%), and dyslipidemia (9.2%). The study also found that anti-dsDNA antibodies can reduce the likelihood of developing hypertension by 40%. This research contributes to the medical literature on SLE and sets the stage for future research on personalized healthcare strategies for managing SLE and its complications. CONCLUSION: This study highlights that a considerable proportion of SLE patients(~50%) develop cardiovascular complications, with hypertension, valvular heart diseases, and dyslipidemia being the most common. We also discovered that anti-double-stranded deoxyribonucleic acid antibodies (Anti-dsDNA) reduce the likelihood of developing hypertension.

3.
ISA Trans ; 147: 337-349, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342649

RESUMO

This paper proposes a novel iterative algorithm for the joint state and parameter estimation of bilinear state-space systems disturbed by colored noise. Estimating the states and parameters of such systems is challenging due to their nonlinearity and greater number of parameters compared to linear systems. Our method is to modify the Kalman filtering appropriately to estimate the unknown states of bilinear systems. Once the unknown states are estimated, we develop the Kalman filtering-based multi-innovation gradient-based iterative (KF-MIGI) algorithm for parameter estimation. To further improve estimation accuracy and cope with colored noises, we introduce a data filtering-based KF-MIGI algorithm that uses an adaptive filter to filter input-output data. Additionally, we compare the gradient-based iterative algorithm and the stochastic gradient algorithm. The effectiveness of the proposed algorithm is demonstrated through numerical examples.

4.
Aesthetic Plast Surg ; 48(5): 803-815, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37679560

RESUMO

INTRODUCTION: Autologous costal cartilage harvest is a common procedure in craniofacial reconstruction due to its stability, dependability, and diversity. However, such a procedure is associated with severe donor-site pain postoperatively. Therefore, we aim through this study to compare the efficacy of intercostal nerve block in the management of postoperative pain in patients undergoing costal cartilage harvest for craniofacial reconstruction. METHOD: This systematic review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. The study systematically reviewed MEDLINE, Cochrane, and EMBASE databases without time-limitation. RESULTS: As a result of reviewing the literature, 33 articles were screened by full-text resulting in 14 articles which met our inclusion/exclusion criteria. However, only four high-quality RCT articles were included in the quantitative synthesis (meta-analysis). The findings of this study suggest that there is no significant difference in pain scores between ICNB and control groups at 12, 24, and 48 h postoperatively, both at rest and with coughing. Therefore, both techniques are considered safe and effective. CONCLUSION: Our results show evidence of favorable outcome of preventive donor-site analgesia with ICNB for harvesting autologous costal cartilage in multiple studies. However, the overall outcomes were insignificant between the two arms. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Cartilagem Costal , Animais , Humanos , Nervos Intercostais , Dor Pós-Operatória/prevenção & controle , Manejo da Dor
5.
Cureus ; 15(11): e49377, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38146572

RESUMO

Background and aim Early detection and intervention can improve the treatment outcome of childhood mental disorders, and primary school teachers may play an important role in referring suspected cases to mental health facilities if they have good awareness and attitudes toward these disorders. The aim of this study is to assess the awareness and attitudes of primary school teachers toward childhood mental disorders in Taif, Saudi Arabia. Methods This is a cross-sectional study conducted among classroom teachers in primary schools in Taif, Kingdom of Saudi Arabia. It was conducted during the period from 2022 to 2023 in both public and private schools. An anonymous, self-administered, online questionnaire was used to assess participants' awareness and attitudes toward pupils with mental health issues. The collected data were analyzed using the chi-square test to examine the associations between various categories and the ANOVA test to compare means. Results The study included 417 teachers, 63.5% of whom were males, the mean of their ages was 39.59 years (SD±8.66), and the mean of their work experience was 12.8 years (SD±8.02) in different teaching specialties. Among participants, 60.2% claimed that no pupils had mental health problems in their classes, 80.1% had not referred any pupils to mental health facilities, and 88.5% did not receive any training related to childhood mental health problems. A humble percent (12.2%) of the participants claimed a good awareness of the signs and symptoms of childhood disorders. Only 54% of teachers advise visiting a psychiatric clinic in case of psychiatric problems, and a similar percentage of teachers believe that psychiatric drugs cause addiction. The male gender, being specialized in humanitarian subjects, having relatives or friends with childhood mental disorders, and receiving training related to childhood mental health were significantly associated with teachers' better awareness. Conclusion Primary school teachers generally lack awareness of childhood mental health and have underestimation and poor recognition of cases of mental disorders. There are many teachers who also have unfavorable attitudes toward psychiatric disorders, patients, and treatments, which requires much effort to improve their awareness and attitudes toward childhood mental disorders.

6.
Nanoscale Adv ; 5(18): 4819-4832, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37705803

RESUMO

Here, the hydromagnetic entropy optimized flow of a hybrid (Pb + Fe2O3/C2H6O2) nanoliquid by a curved stretchable surface is addressed. The Darcy-Forchheimer model is utilized for porous space. Lead (Pb) and ferric oxide (Fe2O3) are considered the nanoparticles and ethylene glycol (C2H6O2) as the base liquid. Thermal expression consists of dissipation and ohmic heating. Entropy generation is under consideration. The Cattaneo-Christov heat flux impact is discussed. Non-dimensional partial expressions by adequate transformations have been reduced to ordinary differential systems. The ND-solve technique is implemented for numerical solutions of dimensionless systems. Graphical illustrations of velocity, thermal field and entropy against influential variables for both nanoliquid (Pb/C2H6O2) and hybrid nanoliquid (Pb + Fe2O3/C2H6O2) are presented. Graphical illustrations of velocity, thermal field and entropy against sundry variables for both nanoliquid (Pb/C2H6O2) and hybrid nanoliquid (Pb + Fe2O3/C2H6O2) are presented. Influences of sundry variables on the Nusselt number and drag force for both nanoliquid (Pb/C2H6O2) and hybrid nanoliquid (Pb + Fe2O3/C2H6O2) are examined. A higher thermal relaxation time tends to intensify the heat transport rate and temperature. An increment in the magnetic variable leads to an enhancement of the entropy and thermal field. An improvement in liquid flow is seen for volume fraction variables. Velocity against the porosity variable and Forchheimer number is reduced. The Brinkman number leads to maximization of entropy generation.

7.
Cureus ; 15(12): e50933, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38249252

RESUMO

Background Childhood obesity is an alarming health problem. Early feeding habits and factors are among the etiological factors contributing to obesity. Objectives The objective of this study is to evaluate the correlation between breastfeeding, alongside other relevant factors, and their potential role as preventative measures against obesity. Methods A cross-sectional hospital-based study was conducted on children who attended a pediatric clinic. Demographic, clinical, and anthropometric measurements were taken from the hospital records. A questionnaire was completed by parents telephonically. Overweight was identified as a body mass index (BMI) of > 85-95% and obesity as a BMI of > 95%. Results A total of 101 children, with a mean age of 8.88 ± 4.01 (range one to 18) years, were involved, of whom 58.4% were boys. A high BMI (overweight or obese) was found in 30 (29.7%) children. The highest BMIs were among soft drink consumers [two children (66.7%) consumed daily and eight children (40%) consumed monthly], high birth weight in two children (40%), cow's milk formula feeding in eight children (38%), and weekly fast food consumption in 18 children (35%), none of these were statistically significant. Nevertheless, there was a significant association between mean electronic device usage and high (204.5 ± 164.76 hours) and normal BMI (147.61 ± 110.24 hours) (p-value < 0.05). Conclusion This small cross-sectional study shows that almost one-third of the included children were overweight or obese, which is comparable to what has been published in the literature. Moreover, there was a potential link between some factors and obesity, especially screen time, which may contribute to the controversial literature.

8.
Sci Rep ; 11(1): 22838, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819552

RESUMO

The addressed work explains SWCNTs (Single walled carbon nanotubnes) and MWCNTs (Multi walled carbon nanotubnes) nanofluid flow under the influences of temperature dependent viscosity and mixed convection. Comparative study of SWCNTs and MWCNTs suspended in base liquid is presented. Further heat and mass transfer are addressed for nanofluid effected by radiation, heat generation/absorption and diffusion species. Mathematical development of problem is taken in cylindrical coordinates. System of highly nonlinear differential equations are constructed via appropriate transformations. The system of equations are tackled numerically by bvp4c MATLAB solver. The findings of the study show that larger volume fraction [Formula: see text] contributes to enhance the nanoliquid flow. The velocity by submerging MWCNTs is noted higher than SWCNTs. Furthermore, the relationship between the viscosity variable [Formula: see text] and the temperature is such that the temperature near the surface decreases with increase in [Formula: see text], while at the same time the temperature away from the surface increases. Subsequently, higher temperature is observed in SWCNTs-liquid compared to the MWCNTs-liquid to the similar values of [Formula: see text]. Further, heat transfer is an increasing function of varying viscosity variable [Formula: see text].

9.
PeerJ Comput Sci ; 7: e570, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34435091

RESUMO

Question classification is one of the essential tasks for automatic question answering implementation in natural language processing (NLP). Recently, there have been several text-mining issues such as text classification, document categorization, web mining, sentiment analysis, and spam filtering that have been successfully achieved by deep learning approaches. In this study, we illustrated and investigated our work on certain deep learning approaches for question classification tasks in an extremely inflected Turkish language. In this study, we trained and tested the deep learning architectures on the questions dataset in Turkish. In addition to this, we used three main deep learning approaches (Gated Recurrent Unit (GRU), Long Short-Term Memory (LSTM), Convolutional Neural Networks (CNN)) and we also applied two different deep learning combinations of CNN-GRU and CNN-LSTM architectures. Furthermore, we applied the Word2vec technique with both skip-gram and CBOW methods for word embedding with various vector sizes on a large corpus composed of user questions. By comparing analysis, we conducted an experiment on deep learning architectures based on test and 10-cross fold validation accuracy. Experiment results were obtained to illustrate the effectiveness of various Word2vec techniques that have a considerable impact on the accuracy rate using different deep learning approaches. We attained an accuracy of 93.7% by using these techniques on the question dataset.

10.
Chaos Solitons Fractals ; 143: 110601, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33551580

RESUMO

Considering the great effect of vaccination and the unpredictability of environmental variations in nature, a stochastic Susceptible-Vaccinated-Infected-Susceptible (SVIS) epidemic model with standard incidence and vaccination strategies is the focus of the present study. By constructing a series of appropriate Lyapunov functions, the sufficient criterion R 0 s > 1 is obtained for the existence and uniqueness of the ergodic stationary distribution of the model. In epidemiology, the existence of a stationary distribution indicates that the disease will be persistent in a long term. By taking the stochasticity into account, a quasi-endemic equilibrium related to the endemic equilibrium of the deterministic system is defined. By means of the method developed in solving the general three-dimensional Fokker-Planck equation, the exact expression of the probability density function of the stochastic model around the quasi-endemic equilibrium is derived, which is the key aim of the present paper. In statistical significance, the explicit density function can reflect all dynamical properties of an epidemic system. Next, a simple result of disease extinction is obtained. In addition, several numerical simulations and parameter analyses are performed to illustrate the theoretical results. Finally, the corresponding results and conclusions are discussed at the end of the paper.

11.
Cureus ; 13(12): e20844, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35141092

RESUMO

BACKGROUND: Choosing a future career is a frightening and anxious decision for medical students; understanding any factor that influences making such a decision will be helpful for the medical students to reach it with satisfaction. AIM: The aim of this study was to determine the factors that would influence the choice of ophthalmology as a future career among medical students in multi-medical colleges in Saudi Arabia. METHODS: This cross-sectional study was conducted for pre-clinical and clinical medical students from February 2021 to May 2021 in multi-medical colleges in Saudi Arabia. The questionnaire used was from previously published research, and it was modified and validated by a board-certified ophthalmologist. RESULTS: A total of 6.1% of all medical students considered ophthalmology as their first choice as a future career; factors that influenced choosing ophthalmology were personal interest, satisfaction from improving patient quality of vision, good patient prognosis, and the appeal of being an ophthalmologist; these factors showed a highly significant difference in comparison to other factors. CONCLUSION: Several factors are explored for choosing ophthalmology as a future specialty; understanding these factors can help medical students determine their choices for a future career.

13.
Chaos Solitons Fractals ; 140: 110238, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32868968

RESUMO

Focusing on deterministic AIDS model proposed by Hyman (2000) and the detailed data from the World Health Organization (WHO), there are three stages of AIDS process which are described as Acute infection period, Asymptomatic phase and AIDS stage. Our paper is therefore concerned with a stochastic staged progression AIDS model with staged treatment. In view of the complexity of random disturbances, we reasonably take second-order perturbation into consideration for realistic sense. By means of our creative transformation technique and stochastic Lyapunov method, a critical value R 0 H > 1 is firstly obtained for the existence and uniqueness of ergodic stationary distribution to the stochastic system. Not only does it respectively reveal the corresponding dynamical effects of the linear and second-order perturbations to the model, but the unified form of second-order and linear fluctuations is derived. Next, some sufficient conditions about extinction of stochastic system are established in view of the basic reproduction number R 0 . Finally, some examples and numerical simulations are introduced to illustrate our analytical results. In addition, some advantages of our new method and theory are highlighted by comparison with other existing results at the end of this paper.

14.
ACS Appl Mater Interfaces ; 12(28): 31459-31466, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32551514

RESUMO

Suitable donor and acceptor distribution in the blended photoactive layer benefits the charge transfer and exciton separation to boost the performance of organic solar cells (OSCs). Herein, we propose a universal solvent-flushing method for building component distribution in photoactive layers based on the different solubilities of the donor and acceptor in acetylacetone (Acac). The donor and acceptor concentration distribution through the photoactive layers is investigated by the time-of-flight secondary-ion mass spectroscopy, and the surface concentration changes are examined by contact angle measurements and atomic force microscopy tests. The charge-transfer properties of OSCs before and after Acac flushing are further investigated by the rectification ratio and light intensity-dependent Jsc and Voc measurements. For inverted OSCs based on PBDB-TF:IT-4F, the power conversion efficiency (PCE) enhances from 12.87 to 14.05%, and for a PBDB-TF:Y6-based device, the PCE also significantly increases from 15.40 to 16.51% because of greatly enhanced Jsc and FF, benefited from enhanced charge transport and suppressed charge recombination by solvent-flushing. Our findings suggest that solvent-flushing is a simply processed and easily controlled method to achieve vertical component distribution in photoactive layers to boost the performance of OSCs.

15.
Small ; 16(32): e2002940, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32583597

RESUMO

For quasi-2D perovskite light-emitting diodes, the introduction of insulating bulky cation reduces the charge transport property, leading to lowered brightness and increased turn-on voltage. Herein, a dual-ligand strategy is adopted to prepare perovskite films by using an appropriate ratio of i-butylammonium (iBA) and phenylethylammonium (PEA) as capping ligands. The introduction of iBA enhances the binding energy of the ligands on the surface of the quasi-2D perovskite, and effectively controls the proportion of 2D perovskite to allow more efficient energy transfer, resulting in the great enhancement of the electric and luminescent properties of the perovskite. The photoluminescence (PL) mapping of the perovskite films exhibits that enhanced photoluminescence performance with better uniformity and stronger intensity can be achieved with this dual-ligand strategy. By adjusting the proportion of the two ligands, sky-blue perovskite light-emitting diodes (PeLEDs) with electroluminescence (EL) peak located 485 nm are achieved with a maximum luminance up to 1130 cd m-2 and a maximum external quantum efficiency (EQE) up to 7.84%. In addition, the color stability and device stability are significantly enhanced by using a dual-ligand strategy. This simple and feasible method paves the way for improving the performance of quasi-2D PeLEDs.

16.
High Blood Press Cardiovasc Prev ; 27(3): 259-264, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253743

RESUMO

INTRODUCTION: The American College of Cardiology (ACC) in USA and the European Society of Cardiology (ESC) in Europe have issued around 25 practice cardiology guidelines since 2008. The attention and impact of these guidelines have not been investigated yet. AIM: In this study, we aim to compare the attention brought up by ACC and ESC guidelines. METHODS: Guideline documents were defined as documents published by either the ACC or the ESC, where recommendations with a specific level of evidence are clearly indicated. These documents were posted on their respective websites. For each document, we extracted the attention on blogs, news, social media, and other platforms to calculate a total score known as the Altmetric Attention Score (AAS). Then we compared AAS, citations, and other indices between ACC and ESC guideline documents. RESULTS: A total of 26 US and 24 European cardiology guidelines were released between 2008 and 2018. We found a significant difference in the median AAS between American and European guidelines (p = 0.048). The median AAS for European and for American guidelines were 159 (104.25-392.5) and 79 (24-169.75), respectively. The US Contribution to the AAS was significantly higher than the European in both the European guidelines (p < 0.001, median contribution values were 7.6% vs 3.4%, respectively), and the American guidelines (p = 0.011, median contribution values were 12% vs 7%, respectively). CONCLUSION: The attention brought up by the European guideline documents was higher than the American guidelines, although most of the attention in both guidelines was contributed to by USA.


Assuntos
Atenção , Atitude do Pessoal de Saúde , Fidelidade a Diretrizes/normas , Conhecimentos, Atitudes e Prática em Saúde , Guias de Prática Clínica como Assunto/normas , Padrões de Prática Médica/normas , Sociedades Médicas/normas , Blogging , Europa (Continente) , Humanos , Meios de Comunicação de Massa , Mídias Sociais , Estados Unidos
17.
Environ Sci Technol ; 54(6): 3353-3362, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32083478

RESUMO

Although two-dimensional titanium carbide (Ti3C2Tx MXene) has emerged as a shining star material in various communities, its environmental behaviors and fate remain unknown. Herein, the colloidal properties and stability of Ti3C2Tx MXene are explored in aquatic systems for the first time, considering the roles of solution chemistry conditions (e.g., pH, ionic types, and strength). It was found that pH had no effect on the stability of Ti3C2Tx in the range of 5.0-11.0, whereas ionic valence and concentrations displayed significant effects on the aggregation behavior of Ti3C2Tx. By employing time-resolved dynamic light scattering measurements, the critical coagulation concentration (CCC) value of Ti3C2Tx was determined to be 12 mM for NaCl. The divalent cations Ca2+ and Mg2+ exhibited higher destabilizing capacity to Ti3C2Tx, as evidenced by the lower CCC values (0.3 and 0.4 mM for CaCl2 and MgCl2, respectively) and faster coagulation rates. Long-term stability studies implied that Ti3C2Tx MXene was less likely to be transported over long distances in the synthetic or natural waters. These findings provided significant insights into the fate and transport of Ti3C2Tx in the aquatic environment.


Assuntos
Cloreto de Sódio , Titânio , Cátions Bivalentes , Soluções
18.
J Phys Chem Lett ; 11(3): 1120-1127, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31967834

RESUMO

Lead halide perovskites have attracted tremendous attention because of their impressive optoelectronic properties. However, the toxicity of lead remains a bottleneck for further commercial development. Two-dimensional Ruddlesden-Popper tin-based perovskites are lead-free and more stable compared to their three-dimensional counterparts, which have great potential in the optoelectronic device field. Herein, we demonstrate high-quality two-dimensional phenylethylammonium tin-iodide perovskite (PEA2SnI4) thin films by using toluene as the antisolvent. Furthermore, the PeLED performance is greatly improved by replacing the PEAI spacer cation with 2-thiopheneethyllamine iodide (TEAI). As a result, a TEA-based PeLED device is achieved with a low turn-on voltage of 2.3 V, a maximum luminance of 322 cd m-2, and maximum external quantum efficiency of 0.62%, which are the highest efficiency and brightness for pure red (emission peak = 638 nm) tin-based PeLEDs to date.

19.
Nat Commun ; 11(1): 182, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924775

RESUMO

Urban activities have profound and lasting effects on the global carbon balance. Here we develop a consistent metabolic approach that combines two complementary carbon accounts, the physical carbon balance and the fossil fuel-derived gaseous carbon footprint, to track carbon coming into, being added to urban stocks, and eventually leaving the city. We find that over 88% of the physical carbon in 16 global cities is imported from outside their urban boundaries, and this outsourcing of carbon is notably amplified by virtual emissions from upstream activities that contribute 33-68% to their total carbon inflows. While 13-33% of the carbon appropriated by cities is immediately combusted and released as CO2, between 8 and 24% is stored in durable household goods or becomes part of other urban stocks. Inventorying carbon consumed and stored for urban metabolism should be given more credit for the role it can play in stabilizing future global climate.

20.
Chaos Solitons Fractals ; 139: 110013, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33519104

RESUMO

This paper is intended to explore a higher order stochastically perturbed SIRI epidemic model with relapse and media coverage. Firstly, we derive sufficient criteria for the existence and uniqueness of an ergodic stationary distribution of positive solutions to the system by establishing a suitable stochastic Lyapunov function. Then we obtain adequate conditions for complete eradication and wiping out of the infectious disease. In a biological interpretation, the existence of a stationary distribution implies that the disease will prevail and persist in the long term. Finally, the theoretical results are illustrated by computer simulations, including two examples based on real-life disease.

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