scholarly journals Accounting for the Role of Asymptomatic Patients in Understanding the Dynamics of the COVID-19 Pandemic: A Case Study from Singapore

2021 ◽  
Author(s):  
Fu Teck Liew ◽  
Palash Ghosh ◽  
Bibhas Chakraborty
Keyword(s):  
Reproduction Number ◽  
Exponential Model ◽  
Epidemiological Models ◽  
Early Stages ◽  
Asymptomatic Patients ◽  
Time Period ◽  
Simulation Results ◽  
Asymptomatic Infections

Objectives: To forecast the true growth of COVID-19 cases in Singapore after accounting for asymptomatic infections, we study and make modifications to the SEIR (Susceptible-Exposed-Infected-Recovered) epidemiological model by incorporating hospitalization dynamics and the presence of asymptomatic cases. We then compare the simulation results of our three epidemiological models of interest against the daily reported COVID-19 case counts across the time period from 23rd January to 6th April 2020. Finally, we compare and evaluate on the performance and accuracy of the aforementioned models' simulations. Methods: Three epidemiological models are used to forecast the true growth of COVID-19 case counts by accounting for asymptomatic infections in Singapore. They are the exponential model, SEIR model with hospitalization dynamics (SEIHRD), and the SEIHRD model with inclusion of asymptomatic cases (SEAIHRD). Results: Simulation results of all three models reflect underestimation of COVID-19 cases in Singapore during the early stages of the pandemic. At a 40% asymptomatic proportion, we report basic reproduction number R0 = 3.28 and 3.74 under the SEIHRD and SEAIHRD models respectively. At a 60% asymptomatic proportion, we report R0 = 3.48 and 3.96 under the SEIHRD and SEAIHRD models respectively. Conclusions: Based on the results of different simulation scenarios, we are highly confident that the number of COVID-19 cases in Singapore was underestimated during the early stages of the pandemic. This is supported by the exponential increase of COVID-19 cases in Singapore as the pandemic developed.

Mathematical Study of a Class of Epidemiological Models with Multiple Infectious Stages

2020 ◽  
Vol 21 (3-4) ◽  
pp. 259-274
Author(s):  
S. Bowong ◽  
A. Temgoua ◽  
Y. Malong ◽  
J. Mbang
Keyword(s):  
Theoretical Study ◽  
Reproduction Number ◽  
Communicable Disease ◽  
Transmission Dynamics ◽  
Asymptotically Stable ◽  
Epidemiological Models ◽  
Mathematical Study ◽  
Globally Asymptotically Stable ◽  
Disease Free

AbstractThis paper deals with the mathematical analysis of a general class of epidemiological models with multiple infectious stages for the transmission dynamics of a communicable disease. We provide a theoretical study of the model. We derive the basic reproduction number $\mathcal R_0$ that determines the extinction and the persistence of the infection. We show that the disease-free equilibrium is globally asymptotically stable whenever $\mathcal R_0 \leq 1$, while when $\mathcal R_0 \gt 1$, the disease-free equilibrium is unstable and there exists a unique endemic equilibrium point which is globally asymptotically stable. A case study for tuberculosis (TB) is considered to numerically support the analytical results.

scholarly journals THE STRUCTURE OF SPACE: CUBISM AND MODERNISM. FIGURES AND ICONS IN JOSEF GOČÁR’S WORK

2017 ◽  
Vol 41 (1) ◽  
pp. 9-21
Author(s):  
Domenico Giuseppe CHIZZONITI
Keyword(s):  
Architectural Design ◽  
Close Association ◽  
Fine Arts ◽  
Practical Experience ◽  
Design Work ◽  
Time Period ◽  
The Individual ◽  
The City

This research paper relates to a number of works by Josef Gočár, a Bohemian architect who was active in a time period between “Cubist” vanguardism and “Rationalist” modernism. The theme regards the search for a general method which evaluates the key elements of the structure of space in architectural design. The main asset of architectural composition has traditionally been the close association between the syntactic order of the elements and a semantic perception of space. The aim of this essay is to explore the relation between the role of the experimental design regarding the multiple and changeable architectural experience and the creative process of architectural work. The methodological experience hereby demonstrated refers to a specific case study that belongs to the scientific research carried out by Gočár and his researchers’ group at the Prague Fine Arts Academy (AVU). His work is hereby re-interpreted in an effort to explore the experiential contribution to the architectural design discipline, and the figurative aspect, by reexamining various characteristics of his practical experience as an architect involved in the civic priorities of the city, from the scale of urban settlement to the individual design work.

The Establishment of Banking Institutions in a Backward Economy: Brazil, 1800–1851

1975 ◽  
Vol 49 (4) ◽  
pp. 446-472 ◽  
Author(s):  
Carlos Manuel Peláez
Keyword(s):  
Economic Growth ◽  
Growth And Development ◽  
Economic Growth And Development ◽  
Early Stages ◽  
Banking Institutions

This study analyzes the Brazilian experience as a case study in the role of banking in the early stages of economic growth and development.

scholarly journals Role of temperature and humidity in the modulation of the doubling time of COVID-19 cases

2020 ◽  
Author(s):  
B Oliveiros ◽  
L Caramelo ◽  
N C Ferreira ◽  
F Caramelo
Keyword(s):  
Doubling Time ◽  
Mainland China ◽  
Exponential Model ◽  
Meteorological Variables ◽  
Cultural Aspects ◽  
The North ◽  
Time Period ◽  
Rate Of Progression ◽  
Containment Measures

AbstractCOVID-19 is having a great impact on public health, mortality and economy worldwide, in spite of the efforts to prevent its epidemy. The SARS-CoV-2 genome is different from that of MERS-CoV and SARS-CoV, although also expected to spread differently according to meteorological conditions. Our main goal is to investigate the role of some meteorological variables on the expansion of this outbreak.In this study, an exponential model relating the number of accumulated confirmed cases and time was considered. The rate of COVID-19 spread, using as criterion the doubling time of the number of confirmed cases, was used as dependent variable in a linear model that took four independent meteorological variables: temperature, humidity, precipitation and wind speed. Only China cases were considered, to control both cultural aspects and containment policies. Confirmed cases and the 4 meteorological variables were gathered between January 23 and March 1 (39 days) for the 31 provinces of Mainland China. Several periods of time were sampled for each province, obtaining more than one value for the rate of disease progression. Two different periods of time were tested, of 12 and 15 days, along with 3 and 5 different starting points in time, randomly chosen. The median value for each meteorological variable was computed, using the same time period; models with were selected. The rate of progression and doubling time were computed and used to fit a linear regression model. Models were evaluated using α = 0.05.Results indicate that the doubling time correlates positively with temperature and inversely with humidity, suggesting that a decrease in the rate of progression of COVID-19 with the arrival of spring and summer in the north hemisphere. A 20°C increase is expected to delay the doubling time in 1.8 days. Those variables explain 18% of the variation in disease doubling time; the remaining 82% may be related to containment measures, general health policies, population density, transportation or cultural aspects.

Accountability in times of exception: an exploratory study of account-giving practices during the early stages of the COVID-19 pandemic in Italy

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Michele Andreaus ◽  
Leonardo Rinaldi ◽  
Caterina Pesci ◽  
Andrea Girardi
Keyword(s):  
Design Methodology ◽  
Public Governance ◽  
Content Type ◽  
Social Actors ◽  
Early Stages ◽  
Italian Government ◽  
The Government ◽  
Account Giving

PurposeThe purpose of this paper is to explore the role of accountability in times of exception. The Italian government's account-giving practices are critically analysed with respect to the distinct modes in which duties of accountability are discharged for the exceptional measures taken during the early stages of the COVID-19 pandemic outbreak in early 2020.Design/methodology/approachThis paper draws on an exploratory case study. The case analysis draws primarily on data obtained through publicly available documents and covers the period between January 1 and August 7, 2020.FindingsThe paper reveals that the Italian government employed various accountability styles (rebuttal, dismissal, reactive, proactive and coactive). Each style influenced both how the government justified its conduct and how it sought to form distinctive relationships with social actors.Originality/valueThe paper uses the notion of “styles of accountability” to empirically illustrate how an unprecedented public governance challenge can reveal broader accountability trends. The paper contributes to accountability research by elucidating how governments tackle ambiguity and uncertainty in their systems of public accountability in extraordinary times.

scholarly journals Development of Areas and Public Purpose Investments in Suburban Territories

2014 ◽  
Vol 22 (2) ◽  
pp. 86-97
Author(s):  
Ada Wolny ◽  
Alina Źróbek-Rózańska ◽  
Ryszard Źróbek ◽  
Marek Piotrowski ◽  
Jens Frey
Keyword(s):  
Local Community ◽  
Social Infrastructure ◽  
Suburban Areas ◽  
Public Investments ◽  
Public Purpose ◽  
Time Period ◽  
The Relationship

Abstract Suburban areas are subjected to particularly strong investment pressure, thus facing the challenge arising from the need to impose new spatial order. Satisfying the residents’ expectations by implementing necessary technical and social infrastructure becomes a priority. Therefore, public investments play an important role in suburban areas. The article discusses the role of public purpose goals and their achievement using a case study which encompassed the outskirts of Olsztyn and consisted of detailed analyses of two gminas (communes) adjacent to the city. The research covered the time period from 2006 to 2010. The relationship between the development of housing functions in a suburban area and the location of public purpose investments such as technical and social infrastructure has been documented. The execution of public purpose projects is a follow-up of the development strategies prepared for the gminas where public investments are shown as a stimulant of suburban development. It has been demonstrated that decisions permitting such investments to be carried out are issued in response to the needs of the local community and investors moving to suburban territories.

Introduction

2018 ◽  
pp. 1-21
Author(s):  
Philip Michael Forness
Keyword(s):  
Strong Evidence ◽  
Late Antiquity ◽  
Important Place ◽  
Time Period ◽  
Basic Orientation ◽  
History Of ◽  
Historical Contextualization ◽  
Basic Characteristics

The introduction identifies the central questions of the book and provides a basic orientation to the major figures and time period. The Christological controversies have long held an important place in the history of early Christianity, and strong evidence suggests that these quarrels affected all levels of society. This work argues that preaching served as a means of communicating Christological concepts to broad audiences in late antiquity. The homilies of Jacob of Serugh have long resisted efforts of historical contextualization and serve here as a case study for the role of sermons in spreading Christological doctrine. A brief account of Jacob’s life drawn from contemporaneous works establishes the basic characteristics of his time. A summary of the long debate over Jacob’s Christological perspective follows and leads into the structure of the monograph.

scholarly journals System Dynamics Modelling of Remanufacturing and Recycling Mode Based on Closed-Loop Across-Chain Competition

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Shidi Miao ◽  
Deyun Chen ◽  
Tengfei Wang
Keyword(s):  
Supply Chain ◽  
Closed Loop ◽  
Third Party ◽  
Total Revenue ◽  
Proposed Model ◽  
Dynamics Modelling ◽  
Simulation Results ◽  
The Impact

To face the reality of resources exhaustion, the significance of recycling and remanufacturing in the closed-loop chain has become quite evident. This paper constructs a competitive recycling and remanufacturing model of the closed-loop supply chain through a case study of Midea Corp. and Gree Corp. and explores the impact of two recycling modes on total revenue of the supply chain and market share. The simulation results show that the total revenue of the supply chain will benefit from the increasing coverage points by the third party and the increasing environmental awareness of certain regions. The retailers show more enthusiasm of recycling through certain amendment of the contract between manufacturers and retailers. The time of payment could be shortened in closed loop. Moreover, the improvement of recycling mechanism of the retailers can enlarge the share of supply chain market. Guiding role of the proposed model and the simulation results played in establishing a better supply chain mode is presented.

The ambivalent role of the institution in the history of child and adolescent psychiatry: a case study of the Hawthorn Centre in Michigan, USA

2020 ◽  
Vol 31 (4) ◽  
pp. 440-454
Author(s):  
Robert Cesaro ◽  
Laura Hirshbein
Keyword(s):  
Psychiatric Care ◽  
Child And Adolescent Psychiatry ◽  
Economic Factors ◽  
Psychiatric Institutions ◽  
Time Period ◽  
The Usa ◽  
History Of ◽  
Different Characteristics

Historians have examined the role of psychiatric institutions in the USA and addressed whether this form of care helped or harmed patients (depending on the perspective of the time period, historical actors, and historians). But the story for children’s mental institutions was different. At the time when adult institutions were in decline, children’s mental hospitals were expanding. Parents and advocates clamoured for more beds and more services. The decrease in facilities for children was more due to economic factors than ideological opposition. This paper explores a case study of a hospital in Michigan as a window into the different characteristics of the discussion of psychiatric care for children.

scholarly journals The diachronic development of combining forms in scientific writing

Lege Artis ◽  
2017 ◽  
Vol 2 (2) ◽  
pp. 185-249 ◽  
Author(s):  
Katrin Menzel ◽  
Stefania Degaetano-Ortlieb
Keyword(s):  
Critical Discussion ◽  
Scientific Writing ◽  
Scientific Publications ◽  
Scientific Texts ◽  
Scholarly Journals ◽  
Early Stages ◽  
Diachronic Development

Abstract This paper addresses the diachronic development of combining forms in English scientific texts over approximately 350 years, from the early stages of the first scholarly journals that were published in English to contemporary English scientific publications. In this paper a critical discussion of the category of combining forms is presented and a case study is produced to examine the role of selected combining forms in two diachronic English corpora.

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