scholarly journals Social heterogeneity and the COVID-19 lockdown in a multi-group SEIR model

2021 ◽  
Vol 9 (1) ◽  
pp. 14-21
Author(s):  
Jean Dolbeault ◽  
Gabriel Turinici

Abstract The goal of the lockdown is to mitigate and if possible prevent the spread of an epidemic. It consists in reducing social interactions. This is taken into account by the introduction of a factor of reduction of social interactions q, and by decreasing the transmission coefficient of the disease accordingly. Evaluating q is a difficult question and one can ask if it makes sense to compute an average coefficient q for a given population, in order to make predictions on the basic reproduction rate ℛ0, the dynamics of the epidemic or the fraction of the population that will have been infected by the end of the epidemic. On a very simple example, we show that the computation of ℛ0 in a heterogeneous population is not reduced to the computation of an average q but rather to the direct computation of an average coefficient ℛ0. Even more interesting is the fact that, in a range of data compatible with the Covid-19 outbreak, the size of the epidemic is deeply modified by social heterogeneity, as is the height of the epidemic peak, while the date at which it is reached mainly depends on the average ℛ0 coefficient. This paper illustrates more technical results that can be found in [4], with new numerical computations. It is intended to draw the attention on the role of heterogeneities in a population in a very simple case, which might be difficult to apprehend in more realistic but also more complex models.

Author(s):  
Jean Dolbeault ◽  
Gabriel TURINICI

The goal of the lockdown is to mitigate and if possible prevent the spread of an epidemic. It consists in reducing social interactions. This is taken into account by the introduction of a factor of reduction of social interactions q, and by decreasing the transmission coefficient of the disease accordingly. Evaluating q is a difficult question and one can ask if it makes sense to compute an average coefficient q for a given population, in order to make predictions on the basic reproduction rate R0, the dynamics of the epidemic or the fraction of the population that will have been infected by the end of the epidemic. On a very simple example, we show that the computation of R0 in a heterogeneous population is not reduced to the computation of an average q but rather to the direct computation of an average coefficient R0. Even more interesting is the fact that, in a range of data compatible with the Covid-19 outbreak, the size of the epidemic is deeply modified by social heterogeneity, as is the height of the epidemic peak, while the date at which it is reached mainly depends on the average R0 coefficient.


Algorithms ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 94
Author(s):  
Sharif Noor Zisad ◽  
Mohammad Shahadat Hossain ◽  
Mohammed Sazzad Hossain ◽  
Karl Andersson

A novel coronavirus (COVID-19), which has become a great concern for the world, was identified first in Wuhan city in China. The rapid spread throughout the world was accompanied by an alarming number of infected patients and increasing number of deaths gradually. If the number of infected cases can be predicted in advance, it would have a large contribution to controlling this pandemic in any area. Therefore, this study introduces an integrated model for predicting the number of confirmed cases from the perspective of Bangladesh. Moreover, the number of quarantined patients and the change in basic reproduction rate (the R0-value) can also be evaluated using this model. This integrated model combines the SEIR (Susceptible, Exposed, Infected, Removed) epidemiological model and neural networks. The model was trained using available data from 250 days. The accuracy of the prediction of confirmed cases is almost between 90% and 99%. The performance of this integrated model was evaluated by showing the difference in accuracy between the integrated model and the general SEIR model. The result shows that the integrated model is more accurate than the general SEIR model while predicting the number of confirmed cases in Bangladesh.


2020 ◽  
Author(s):  
Tito Dias Junior ◽  
Camila Bueno Machado

AbstractIn this work, the modified SEIR model was proposed to account separately for the tested and isolated cases, with severe and critical symptoms, from those not tested, with mild and moderate symptoms. Two parameters were estimated and evaluated for the cases registered in Rondônia-Brazil, between March 20 and April 22. The basic reproduction rate did not remain constant during the period, showing variations eventually due to social behavior. The results show that the increase in the proportion of testing to about 56% provided a significant decrease in the confirmed cases since the expansion of the tested cases beyond the current testing criterion (20%) would help to identify and isolate also mild and moderate cases, generally referred to as asymptomatic.


Author(s):  
Gulbarshyn Chepurko ◽  
Valerii Pylypenko

The paper examines and compares how the major sociological theories treat axiological issues. Value-driven topics are analysed in view of their relevance to society in times of crisis, when both societal life and the very structure of society undergo dramatic change. Nowadays, social scientists around the world are also witnessing such a change due to the emergence of alternative schools of sociological thought (non-classical, interpretive, postmodern, etc.) and, subsequently, the necessity to revise the paradigms that have been existed in sociology so far. Since the above-mentioned approaches are often used to address value-related issues, building a solid theoretical framework for these studies takes on considerable significance. Furthermore, the paradigm revision has been prompted by technological advances changing all areas of people’s lives, especially social interactions. The global human community, integral in nature, is being formed, and production of human values now matters more than production of things; hence the “expansion” of value-focused perspectives in contemporary sociology. The authors give special attention to collectivities which are higher-order units of the social system. These units are described as well-organised action systems where each individual performs his/her specific role. Just as the role of an individual is distinct from that of the collectivity (because the individual and the collectivity are different as units), so too a distinction is drawn between the value and the norm — because they represent different levels of social relationships. Values are the main connecting element between the society’s cultural system and the social sphere while norms, for the most part, belong to the social system. Values serve primarily to maintain the pattern according to which the society is functioning at a given time; norms are essential to social integration. Apart from being the means of regulating social processes and relationships, norms embody the “principles” that can be applied beyond a particular social system. The authors underline that it is important for Ukrainian sociology to keep abreast of the latest developments in the field of axiology and make good use of those ideas because this is a prerequisite for its successful integration into the global sociological community.


2017 ◽  
Vol 14 (1) ◽  
pp. 156-173
Author(s):  
Vikram Singh

This  article  attempts to  analyse  the  process  of  sustainable  livelihood  through skill development and its conceptual and theoretical understanding in India with reference to rural youth. In India skill development is demanded for economic growth and inclusive development; hence the rural population cannot be overlooked. Employable skills alone have not been able to generate sufficient employment among rural youth or address/promote well-being and sustainable livelihood. Various frameworks associated with skill development leave scope for reforms to strengthen the implementation of various policy shifts in respect of rural development and government/non-government organisations. The process of skill development for rural youth through the establishment of institutions, launch of policy/programmes and their linkages with micro-finance are considered, as the distinctive nature and features of micro-finance in relation to the forces of societal structure, social relationships, and social interactions leading towards collective interests and norms that shape the lives of rural youth. Lastly, analysis is done and conclusions drawn on the basis of discussion.


Author(s):  
Lexi Eikelboom

This chapter proposes a framework for approaching the theological significance of rhythm through phenomenology, prosody, and the social sciences. In accordance with the general categories of phenomenology established by Merleau-Ponty and the “rhythmanalysis” of Henri Lefebvre, the chapter investigates two experiences of rhythm: approaches to analysing the human encounter with rhythm in the reading of poetry and the role of rhythm in social interactions introduced through commonalities between rhythm in conversation and in jazz performance. These explorations establish two features of rhythm that are of analytical importance for the chapters that follow: (1) the synchronic and the diachronic as two necessary but distinct theoretical perspectives on rhythm, each of which emphasizes different features of rhythm and (2) the importance of interruption for understanding rhythm’s significance.


2021 ◽  
pp. 019791832098883
Author(s):  
Irena Kogan ◽  
Jörg Dollmann ◽  
Markus Weißmann

This article examines the association between accented speech and the formation of friendships and partnerships among immigrants and native-born majority residents in Germany. Drawing on the sixth wave of the German extension of the Children of Immigrants Longitudinal Survey in Four European Countries, we analyze a neglected aspect of language — pronunciation — and find that speaking with a foreign accent is a more important correlate of the incidence of interethnic partnerships than of interethnic friendships. We argue that beyond its primary function of understandability, accented speech possesses socially communicative power. Accent transmits signals of an individual’s foreignness and cultural differences and, thus, becomes an additional marker of social distance. Such signals serve as a greater obstacle to more consequential intimate interethnic relations such as partnerships. Our findings extend the scholarly debate on the role of symbolic boundaries in social interactions between ethnic groups by yet another important boundary maker — accent.


Author(s):  
Helena Bulińska-Stangrecka ◽  
Anna Bagieńska

The COVID-19 pandemic is affecting the mental health of employees. Deterioration of the well-being of workers is also caused by changes in the working environment. Remote working can affect both social interactions and job satisfaction. The purpose of the study is to examine what factors influence job satisfaction in the context of remote work caused by a pandemic. The study analyses whether employee relations and interpersonal trust are related to the level of perceived job satisfaction. The investigation started with a literature review and then research hypotheses have been formulated. Based on an empirical study, carried out on a sample of 220 IT employees during the pandemic, an analysis of the mediating role of trust in links between employee relations and perceived job satisfaction was conducted. The current study found that positive employee relations contribute to the level of job satisfaction. Additionally, trust is an important factor that mediates these relationships. Based on the results of the research, it was possible to describe the mechanism of shaping a supportive work environment during a pandemic.


2012 ◽  
Vol 2012 ◽  
pp. 1-20 ◽  
Author(s):  
Felipe de Almeida Sassi ◽  
Algemir Lunardi Brunetto ◽  
Gilberto Schwartsmann ◽  
Rafael Roesler ◽  
Ana Lucia Abujamra

Gliomas are the most incident brain tumor in adults. This malignancy has very low survival rates, even when combining radio- and chemotherapy. Among the gliomas, glioblastoma multiforme (GBM) is the most common and aggressive type, and patients frequently relapse or become refractory to conventional therapies. The fact that such an aggressive tumor can arise in such a carefully orchestrated organ, where cellular proliferation is barely needed to maintain its function, is a question that has intrigued scientists until very recently, when the discovery of the existence of proliferative cells in the brain overcame such challenges. Even so, the precise origin of gliomas still remains elusive. Thanks to new advents in molecular biology, researchers have been able to depict the first steps of glioma formation and to accumulate knowledge about how neural stem cells and its progenitors become gliomas. Indeed, GBM are composed of a very heterogeneous population of cells, which exhibit a plethora of tumorigenic properties, supporting the presence of cancer stem cells (CSCs) in these tumors. This paper provides a comprehensive analysis of how gliomas initiate and progress, taking into account the role of epigenetic modulation in the crosstalk of cancer cells with their environment.


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