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epidemiology
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Finding Influential Nodes in Complex Networks
, M.Sc. Thesis Sharif University of Technology ; Jalili, Mahdi (Supervisor)
Abstract
The modern science of networks helps us to have a better understanding of complex systems. Networked systems can be found everywhere and many systems can be represented by a complex network. A networked structure consists of a number of nodes and links connecting to them. Networks’ ability in information propagation is one of their amazing features that have attracted lots of scholars to work on. It has potential applications in many fields ranging from marketing to biology, epidemiology and sociology. Information propagation studies how information such as computer viruses, contagion, rumor, or new product’s interest propagates over a network. Percolation theory and various epidemic models...
Epidemiology and Networks
, M.Sc. Thesis Sharif University of Technology ; Haji Sadeghi, Mir Omid (Supervisor) ; Razvan, Mahammad Reza (Supervisor)
Abstract
Networks and the epidemiology of directly transmitted infectious diseases are fun-damentally linked. The foundations of epidemiology and early epidemiological models were based on population wide random-mixing, but in practice each individual has a finite set of contacts to whom they can pass infection; the ensemble of all such contacts forms a network. Knowledge of the structure of the network allows models to compute the epidemic dynamics at the population scale from the individual-level behaviour of infections.Motivated by the analysis of social networks, we study a model of random net-works that has both a given degree distribution and a tunable clustering coefficient.We consider two...
The Dynamic and the Geometry of Disease Outbreaks by Redefining the Effective Distance
, M.Sc. Thesis Sharif University of Technology ; Ghanbarnejad, Fakhteh (Supervisor)
Abstract
An infectious disease can spread through different communities via mobility networks. In this study we address three basic questions related to this matter in the meta-population approximation: firstly, where did the disease start? Secondly, when did the disease start? Thirdly, how does it spread in the network? To answer these questions, we introduce a generic mathematical framework with appropriate physical assumptions and study the spread of diseases. Then, with analytical solutions, we bring up different algorithms in order to answer these three questions. Using these algorithms, we redefine the effective distance and arriving time and unveil the simple geometry of the disease outbreak
Temporal dynamics of connectivity and epidemic properties of growing networks
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 93, Issue 1 , 2016 ; 15393755 (ISSN) ; Khani Shirkoohi, M ; Sharif University of Technology
American Physical Society
2016
Abstract
Traditional mathematical models of epidemic disease had for decades conventionally considered static structure for contacts. Recently, an upsurge of theoretical inquiry has strived towards rendering the models more realistic by incorporating the temporal aspects of networks of contacts, societal and online, that are of interest in the study of epidemics (and other similar diffusion processes). However, temporal dynamics have predominantly focused on link fluctuations and nodal activities, and less attention has been paid to the growth of the underlying network. Many real networks grow: Online networks are evidently in constant growth, and societal networks can grow due to migration flux and...
Short-term effects of particle size fractions on circulating biomarkers of inflammation in a panel of elderly subjects and healthy young adults
, Article Environmental Pollution ; Volume 223 , 2017 , Pages 695-704 ; 02697491 (ISSN) ; Naddafi, K ; Kashani, H ; Faridi, S ; Kunzli, N ; Nabizadeh, R ; Momeniha, F ; Gholampour, A ; Arhami, M ; Zare, A ; Pourpak, Z ; Hoseini, M ; Yunesian, M ; Sharif University of Technology
Abstract
Systemic inflammation biomarkers have been associated with risk of cardiovascular morbidity and mortality. We aimed to clarify associations of acute exposure to particulate matter (PM10(PM < 10 μm), PM2.5-10(PM 2.5–10 μm), PM2.5(PM < 2.5 μm), PM1-2.5(PM 1–2.5 μm), and PM1 (PM < 1 μm)) with systemic inflammation using panels of elderly subjects and healthy young adults. We followed a panel of 44 nonsmoking elderly subjects living in a retirement home and a panel of 40 healthy young adults living in a school dormitory in Tehran city, Iran from May 2012 to May 2013. Blood biomarkers were measured one every 7–8 weeks and included white blood cells (WBC), high sensitive C-reactive protein...
Shadow of cyber ostracism over remote environment: Implication on remote work challenges, virtual work environment and employee mental well-being during a Covid-19 pandemic
, Article Acta Psychologica ; Volume 225 , 2022 ; 00016918 (ISSN) ; Murad, M ; Mirza, F ; Chaudhary, N. I ; Saeed, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This study aimed to identify the influence of workplace cyber ostracism on employee online work engagement and employee mental well-being with the mediating roles of remote work challenges such as loneliness, procrastination, work-home interference, and ineffective communication. As amidst lockdown due to COVID-19, the data was collected from 303 respondents through an online questionnaire that was distributed in virtual groups among friends, relatives, and other fellows who were working in the private sector organizations of Pakistan. The hypotheses were tested using the partial least square structural equation modeling PLS-SEM technique. The findings of this study showed that workplace...
Scalable performance analysis of epidemic routing considering skewed location visiting preferences
, Article 27th IEEE International Symposium on Modeling, Analysis, and Simulation of Computer and Telecommunication Systems, MASCOTS 2019, 22 October 2019 through 25 October 2019 ; Volume 2019-October , 2019 , Pages 201-213 ; 15267539 (ISSN); 9781728149509 (ISBN) ; Dalili Yazdi, A ; Entezari Maleki, R ; Sousa, L ; Movaghar, A ; Sharif University of Technology
IEEE Computer Society
2019
Abstract
This paper investigates the performance of epidemic routing, in mobile social networks (MSNs), which makes use of the store-carry-forward paradigm for communication. Real-life mobility traces show that people have skewed location visiting preferences, with some places visited frequently and some others infrequently. In order to model epidemic routing in MSNs, we first analyze the time taken for a node to meet the first node belonging to a set of nodes restricted to move in a specific subarea. Afterwards, a monolithic stochastic reward net (SRN) is proposed to evaluate the delivery delay and the average number of transmissions under epidemic routing by considering skewed location visiting...
Prevalence of smoking in 15-64 years old population of North of Iran: Meta-analysis of the results of non-communicable diseases risk factors surveillance system
, Article Acta Medica Iranica ; Volume 51, Issue 7 , 2013 , Pages 494-500 ; 00446025 (ISSN) ; Moosazadeh, M ; Masouleh, M. F ; Kiani, A ; Fakhri, M ; Sharif University of Technology
2013
Abstract
Smoking is known as a major cause of chronic obstructive pulmonary disease (COPD) and hence immediate and effective interventions are required for its elimination. This study aimed to collect valid data with regard to cigarette smoking in adult population of north of Iran for policy making by a meta-analysis of the documents of national non-communicable disease risk factors surveillance system. We investigated relevant evidences by searching in published and non-electronic databases. Data were extracted based on variables such as year of the study, sex, age group and prevalence of smoking habit. Based on results of heterogeneity, we applied fixed or random effects model to estimate the...
Prevalence of hepatitis e infection in the general population of Iran: a systematic review and meta-analysis
, Article Future Virology ; Volume 12, Issue 4 , 2017 , Pages 227-236 ; 17460794 (ISSN) ; Sedighi, M ; Mostafaei, S ; Miri, A ; Amiri, H ; Abiri, R ; Babaei, F ; Kabir, K ; Moghoofei, M ; Sharif University of Technology
Abstract
Aim: Hepatitis E is a form of acute viral hepatitis, which is caused by hepatitis E virus (HEV). The study objective was to evaluate the prevalence of HEV to provide an overall relative frequency in Iran. Methods: In this study, databases such as PubMed and Scopus were searched using the following keywords according to MeSH, "Hepatitis E virus", "Epidemiology", "Enzyme-linked immunosorbent assay (ELISA)" and "Iran". Then studies which had reported prevalence of HEV were selected. Results: We selected 36 researches out of 9246 for our study. From all the samples, the pooled estimated prevalence of HEV positive was 9.7%. It should be noted that HEV infection's relative frequency varied from...
Performance evaluation of epidemic content retrieval in DTNs with restricted mobility
, Article IEEE Transactions on Network and Service Management ; Volume 16, Issue 2 , 2019 , Pages 701-714 ; 19324537 (ISSN) ; Entezari Maleki, R ; Chatzopoulos, D ; Hui, P ; Trivedi, K. S ; Movaghar, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In some applicable scenarios, such as community patrolling, mobile nodes are restricted to move only in their own communities. Exploiting the meetings of the nodes within the same community and the nodes within the neighboring communities, a delay tolerant network (DTN) can provide communication between any two nodes. In this paper, two analytical models based on stochastic reward nets (SRNs) are proposed to evaluate the performance of the epidemic content retrieval in such multi-community DTNs. Performance measures computed by the proposed models are the average retrieval delay and the average number of transmissions. The monolithic SRN model proposed in the first step is not scalable, in...
Obesity and spinal loads; a combined MR imaging and subject-specific modeling investigation
, Article Journal of Biomechanics ; 2017 ; 00219290 (ISSN) ; Kazemi, H ; Eskandari, A. H ; Arjmand, N ; Sharif University of Technology
Abstract
Epidemiological studies have identified obesity asa possible risk factor for low back disorders. Biomechanical models can help test such hypothesis and shed light on the mechanism involved. A novel subject-specific musculoskeletal-modelling approach is introduced to estimate spinal loads during static activities in five healthy obese (BMI>30kg/m2) and five normal-weight (20
Obesity and spinal loads; a combined MR imaging and subject-specific modeling investigation
, Article Journal of Biomechanics ; Volume 70 , March , 2018 , Pages 102-112 ; 00219290 (ISSN) ; Kazemi, H ; Eskandari, A. H ; Arjmand, N ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Epidemiological studies have identified obesity as a possible risk factor for low back disorders. Biomechanical models can help test such hypothesis and shed light on the mechanism involved. A novel subject-specific musculoskeletal-modelling approach is introduced to estimate spinal loads during static activities in five healthy obese (BMI > 30 kg/m2) and five normal-weight (20 < BMI < 25 kg/m2) individuals. Subjects underwent T1 through S1 MR imaging thereby measuring cross-sectional-area (CSA) and moment arms of trunk muscles together with mass and center of mass (CoM) of T1-L5 segments. MR-based subject-specific models estimated spinal loads using a kinematics/optimization-driven...
Nonlinear robust adaptive sliding mode control of influenza epidemic in the presence of uncertainty
, Article Journal of Process Control ; Volume 56 , 2017 , Pages 48-57 ; 09591524 (ISSN) ; Moradi, H ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
In this paper, a nonlinear robust adaptive sliding mode control strategy is presented for the influenza epidemics in the presence of model uncertainties. The nonlinear epidemiological model of influenza with five state variables (the numbers of susceptible, exposed, infected, asymptomatic and recovered individuals) and two control inputs (vaccination and antiviral treatment) is considered. The objective of the proposed controller is decreasing the number of susceptible and infected humans to zero by tracking the desired scenarios. As a result of this decreasing, the number of exposed and asymptomatic individuals is also decreased and converged to the zero. Accordingly, it is shown that the...
Modeling epidemic routing: capturing frequently visited locations while preserving scalability
, Article IEEE Transactions on Vehicular Technology ; Volume 70, Issue 3 , 2021 , Pages 2713-2727 ; 00189545 (ISSN) ; Dalili Yazdi, A ; Entezari Maleki, R ; Sousa, L ; Movaghar, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
This paper investigates the performance of epidemic routing in mobile social networks considering several communities which are frequently visited by nodes. To this end, a monolithic Stochastic Reward Net (SRN) is proposed to evaluate the delivery delay and the average number of transmissions under epidemic routing by considering skewed location visiting preferences. This model is not scalable enough, in terms of the number of nodes and frequently visited locations. In order to achieve higher scalability, the folding technique is applied to the monolithic model, and an approximate folded SRN is proposed to evaluate performance of epidemic routing. Discrete-event simulation is used to...
How do the smart travel ban policy and intercity travel pattern affect COVID-19 trends? Lessons learned from Iran
, Article PLoS ONE ; Volume 17, Issue 10 October , 2022 ; 19326203 (ISSN) ; Mohammadpour, S. I ; Dahaghin, M ; Sharif University of Technology
Public Library of Science
2022
Abstract
COVID-19, as the most significant epidemic of the century, infected 467 million people and took the lives of more than 6 million individuals as of March 19, 2022. Due to the rapid transmission of the disease and the lack of definitive treatment, countries have employed non-pharmaceutical interventions. This study aimed to investigate the effectiveness of the smart travel ban policy, which has been implemented for non-commercial vehicles in the intercity highways of Iran since November 21, 2020. The other goal was to suggest efficient COVID-19 forecasting tools and to examine the association of intercity travel patterns and COVID-19 trends in Iran. To this end, weekly confirmed cases and...
Hearing loss prevalence and years lived with disability, 1990-2019: Findings from the Global Burden of Disease Study 2019
, Article The Lancet ; Volume 397, Issue 10278 , 2021 , Pages 996-1009 ; 01406736 (ISSN) ; Kamenov, K ; Briant, P. S ; Orji, A. U ; Steinmetz, J. D ; Abdoli, A ; Abdollahi, M ; Abu-Gharbieh, E ; Afshin, A ; Ahmed, H ; Rashid, T. A ; Akalu, Y ; Alahdab, F ; Alanezi, F. M ; Alanzi, T. M ; Al Hamad, H ; Ali, L ; Alipour, V ; Al-Raddadi, R. M ; Amu, H ; Arabloo, J ; Arab-Zozani, M ; Arulappan, J ; Ashbaugh, C ; Atnafu, D. D ; Babar, Z. U. D ; Baig, A. A ; Banik, P. C ; Bärnighausen, T. W ; Barrow, A ; Bender, R. G ; Bhagavathula, A. S ; Bhardwaj, N ; Bhardwaj, P ; Bibi, S ; Bijani, A ; Burkart, K ; Cederroth, C. R ; Charan, J ; Choudhari, S. G ; Chu, D. T ; Couto, R. A. S ; Dagnew, A. B ; Dagnew, B ; Dahlawi, S. M. A ; Dai, X ; Dandona, L ; Dandona, R ; Desalew, A ; Dhamnetiya, D ; Dhimal, M. L ; Dhimal, M ; Doyle, K. E ; Duncan, B. B ; Ekholuenetale, M ; Filip, I ; Fischer, F ; Franklin, R. C ; Gaidhane, A. M ; Gaidhane, S ; Gallus, S ; Ghamari, F ; Ghashghaee, A ; Ghozali, G ; Gilani, S.A ; Glǎvan, I. R ; Golechha, M ; Goulart, B. N. G ; Gupta, V. B ; Gupta, V. K ; Hamidi, S ; Hammond, B. R ; Hay, S. I ; Hayat, K ; Heidari, G ; Hoffman, H. J ; Hopf, K. P ; Hosseinzadeh, M ; Househ, M ; Hussain, R ; Hwang, B. F ; Iavicoli, I ; Ibitoye, S. E ; Ilesanmi, O. S ; Irvani, S. S. N ; Islam, S. M. S ; Iwagami, M ; Jacob, L ; Jayapal, S. K ; Jha, R. P ; Jonas, J. B ; Kalhor, R ; Al-Salihi, N. K ; Kandel, H ; Kasa, A. S ; Kayode, G. A ; Khalilov, R ; Khan, E. A ; Khatib, M. N ; Kosen, S ; Koyanagi, A ; Kumar, G. A ; Landires, I ; Lasrado, S ; Lim, S. S ; Liu, X ; Lobo, S. W ; Lugo, A ; Makki, A ; Mendoza, W ; Mersha, A. G ; Mihretie, K. M ; Miller, T. R ; Misra, S ; Mohamed, T. A ; Mohammadi, M ; Mohammadian Hafshejani, A ; Mohammed, A ; Mokdad, A. H ; Moni, M. A ; Kandel, S. N ; Nguyen, H. L. T ; Nixon, M. R ; Noubiap, J. J ; Nuñez Samudio, V ; Oancea, B ; Oguoma, V. M ; Olagunju, A. T ; Olusanya, B. O ; Olusanya, J. O ; Orru, H ; Owolabi, M. O ; Padubidri, J. R ; Pakshir, K ; Pardhan, S ; Kan, F. P ; Pasovic, M ; Pawar, S ; Pham, H. Q ; Pinheiro, M ; Pourshams, A ; Rabiee, N ; Rabiee, M ; Radfar, A ; Rahim, F ; Rahimi Movaghar, V ; Ur Rahman, M. H ; Rahman, M ; Rahmani, A. M ; Rana, J ; Rao, C. R ; Rao, S. J ; Rashedi, V ; Rawaf, D. L ; Rawaf, S ; Renzaho, A. M. N ; Rezapour, A ; Ripon, R. K ; Rodrigues, V ; Rustagi, N ; Saeed, U ; Sahebkar, A ; Samy, A. M ; Santric-Milicevic, M. M ; Sathian, B ; Satpathy, M ; Sawhney, M ; Schlee, W ; Schmidt, M. I ; Seylani, A ; Shaikh, M. A ; Shannawaz, M ; Shiferaw, W. S ; Siabani, S ; Singal, A ; Singh, J. A ; Singh, J. K ; Singhal, D ; Skryabin, V. Y ; Skryabina, A. A ; Sotoudeh, H ; Spurlock, E. E ; Taddele, B. W ; Tamiru, A. T ; Tareque, M. I ; Thapar, R ; Tovani-Palone, M. R ; Tran, B.X ; Ullah, S ; Tahbaz, S. V ; Violante, F. S ; Vlassov, V ; Vo, B ; Vongpradith, A ; Vu, G. T ; Wei, J ; Yadollahpour, A ; Jabbari, S. H. Y ; Yeshaw, Y ; Yiǧit, V ; Yirdaw, B. W ; Yonemoto, N ; Yu, C ; Yunusa, I ; Zamani, M ; Zastrozhin, M. S ; Zastrozhina, A ; Zhang, Z. J ; Zhao, J. T ; Murray, C. J. L ; Davis, A. C ; Vos, T ; Chadha, S ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Background: Hearing loss affects access to spoken language, which can affect cognition and development, and can negatively affect social wellbeing. We present updated estimates from the Global Burden of Disease (GBD) study on the prevalence of hearing loss in 2019, as well as the condition's associated disability. Methods: We did systematic reviews of population-representative surveys on hearing loss prevalence from 1990 to 2019. We fitted nested meta-regression models for severity-specific prevalence, accounting for hearing aid coverage, cause, and the presence of tinnitus. We also forecasted the prevalence of hearing loss until 2050. Findings: An estimated 1·57 billion (95% uncertainty...
Global trends of hand and wrist trauma: A systematic analysis of fracture and digit amputation using the Global Burden of Disease 2017 Study
, Article Injury Prevention ; 2020 ; Massenburg, B.B ; Morrison, S.D ; Chang, J ; Friedrich, J.B ; Abady, G.G ; Alahdab, F ; Alipour, V ; Arabloo, J ; Asaad, M ; Banach, M ; Bijani, A ; Borzì, A.M ; Briko, N.I ; Castle, C.D ; Cho, D.Y ; Chung, M.T ; Daryani, A ; Demoz, G.T ; Dingels, Z.V ; Do, H.T ; Fischer, F ; Fox, J.T ; Fukumoto, T ; Gebre, A.K ; Gebremichael, B ; Haagsma, J.A ; Haj-Mirzaian, A ; Handiso, D.W ; Hay, S.I ; Hoang, C.L ; Irvani, S.S.N ; Jozwiak, J.J ; Kalhor, R ; Kasaeian, A ; Khader, Y.S ; Khalilov, R ; Khan, E.A ; Khundkar, R ; Kisa, S ; Kisa, A ; Liu, Z ; Majdan, M ; Manafi, N ; Manafi, A ; Manda, A.-L ; Meretoja, T.J ; Miller, T.R ; Mohammadian Hafshejani, A ; Mohammadpourhodki, R ; Mohseni Bandpei, M.A ; Mokdad, A.H ; Naimzada, M.D ; Ndwandwe, D.E ; Nguyen, C.T ; Nguyen, H.L.T ; Olagunju, A.T ; Olagunju, T.O ; Pham, H.Q ; Pribadi, D.R.A ; Rabiee, N ; Ramezanzadeh, K ; Ranganathan, K ; Roberts, N.L.S ; Roever, L ; Safari, S ; Samy, A.M ; Sanchez Riera, L ; Shahabi, S ; Smarandache, C.-G ; Sylte, D.O ; Tesfay, B.E ; Tran, B.X ; Ullah, I ; Vahedi, P ; Vahedian Azimi, A ; Vos, T ; Woldeyes, D. H ; Wondmieneh, A. B ; Zhang, Z. J ; James, S. L ; Sharif University of Technology
BMJ Publishing Group
2020
Abstract
Background: As global rates of mortality decrease, rates of non-fatal injury have increased, particularly in low Socio-demographic Index (SDI) nations. We hypothesised this global pattern of non-fatal injury would be demonstrated in regard to bony hand and wrist trauma over the 27-year study period. Methods: The Global Burden of Diseases, Injuries, and Risk Factors Study 2017 was used to estimate prevalence, age-standardised incidence and years lived with disability for hand trauma in 195 countries from 1990 to 2017. Individual injuries included hand and wrist fractures, thumb amputations and non-thumb digit amputations. Results: The global incidence of hand trauma has only modestly...
Global dynamics of a differential susceptibility model
, Article International Journal of Biomathematics ; Volume 5, Issue 5 , September , 2012 ; 17935245 (ISSN) ; Yasaman, S ; Sharif University of Technology
2012
Abstract
An SIS epidemiological model in a population of varying size with two dissimilar groups of susceptible individuals has been analyzed. We prove that all the solutions tend to the equilibria of the system. Then we use the Poincaré Index theorem to determine the number of the rest points and their stability properties. It has been shown that bistability occurs for suitable values of the involved parameters. We use the perturbations of the pitchfork bifurcation points to give examples of all possible dynamics of the system. Some numerical examples of bistability and hysteresis behavior of the system has been also provided
Global analysis of an SAIS model
, Article Journal of Biological Dynamics ; Volume 6, Issue 2 , 2012 , Pages 457-474 ; 17513758 (ISSN) ; Yasaman, S ; Sharif University of Technology
2012
Abstract
This paper is concerned with global analysis of an SAIS epidemiological model in a population of varying size introduced by Busenberg and van den Driessche. In this model the population is divided into three subgroups of susceptible, asymptomatic and infective individuals. It has been shown that this system has no periodic solutions and all its trajectories tend to the equilibria of the system. We use the Poincaré Index theorem to determine the number of the equilibria and their stability properties. We have shown that bistability occurs for suitable values of parameters and found a set of examples of all possible dynamics of the system
Global analysis of a model of differential susceptibility induced by genetics
, Article Nonlinear Analysis: Real World Applications ; Volume 12, Issue 4 , 2011 , Pages 2183-2197 ; 14681218 (ISSN) ; Yasaman, S ; Sharif University of Technology
2011
Abstract
This paper is concerned with global analysis of an SIS epidemiological model in a population of varying size with two dissimilar groups of susceptible individuals. We prove that this system has no periodic solutions and use the Poincar index theorem to determine the number of rest points and their stability properties. It has been shown that multiple equilibria (bistability) occurs for suitable values of parameters. We also give some numerical examples of all possible bifurcations of this system