scholarly journals A Stochastic Kinetic Type Reactions Model for COVID-19

Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1221
Author(s):  
Giorgio Sonnino ◽  
Fernando Mora ◽  
Pasquale Nardone
Keyword(s):  
Real Data ◽  
Stochastic Noise ◽  
Mathematical Basis ◽  
Sis Model ◽  
Theoretical Predictions ◽  
Coronavirus Infection ◽  
Massive Distribution ◽  
Second Wave ◽  
Stochastic Sis Model

We propose two stochastic models for the Coronavirus pandemic. The statistical properties of the models, in particular the correlation functions and the probability density functions, were duly computed. Our models take into account the adoption of lockdown measures as well as the crucial role of hospitals and health care institutes. To accomplish this work we adopt a kinetic-type reaction approach where the modelling of the lockdown measures is obtained by introducing a new mathematical basis and the intensity of the stochastic noise is derived by statistical mechanics. We analysed two scenarios: the stochastic SIS-model (Susceptible ⇒ Infectious ⇒ Susceptible) and the stochastic SIS-model integrated with the action of the hospitals; both models take into account the lockdown measures. We show that, for the case of the stochastic SIS-model, once the lockdown measures are removed, the Coronavirus infection will start growing again. However, the combined contributions of lockdown measures with the action of hospitals and health institutes is able to contain and even to dampen the spread of the SARS-CoV-2 epidemic. This result may be used during a period of time when the massive distribution of vaccines in a given population is not yet feasible. We analysed data for USA and France. In the case of USA, we analysed the following situations: USA is subjected to the first wave of infection by Coronavirus and USA is in the second wave of SARS-CoV-2 infection. The agreement between theoretical predictions and real data confirms the validity of our approach.

scholarly journals A Stochastic Compartmental Model for COVID-19

2020 ◽  
Author(s):  
Giorgio Sonnino ◽  
Fernando Mora ◽  
Pasquale Nardone
Keyword(s):  
Health Care ◽  
Probability Density Function ◽  
Stochastic Models ◽  
Compartmental Model ◽  
Real Data ◽  
Third Wave ◽  
Theoretical Predictions ◽  
Massive Distribution ◽  
Hospital Capacities

AbstractWe propose two stochastic models for the Coronavirus pandemic. The statistical properties of the models, in particular the correlation functions and the probability density function, have duly been computed. Our models, which generalises a model previously proposed and published in a specialised journal, take into account the adoption of the lockdown measures as well as the crucial role of the hospitals and Health Care Institutes. To accomplish this work we have analysed two scenarios: the SIS-model (Susceptible ⇒ Infectious ⇒ Susceptible) in presence of the lockdown measures and the SIS-model integrated with the action of the hospitals (always in presence of the lockdown measures). We show that in the case of the pure SIS-model, once the lockdown measures are removed, the Coronavirus will start growing again. However, in the second scenario, beyond a certain threshold of the hospital capacities, the Coronavirus is not only kept under control, but its capacity to spread tends to diminish in time. Therefore, the combined effect of the lockdown measures with the action of the hospitals and health Institutes is able to contain and dampen the spread of the SARS-CoV-2 epidemic. This result can be used during a period of time when the massive distribution of delivery of a limited number of vaccines in a given population is not yet feasible. By way of example, we analysed the data for USA and France where the intensities of the noise have been estimated by Statistical Mechanics. In particular, for USA we have analysed two possible hypotheses: USA is still subject to the first wave of infection by and USA is in the second (or third) wave of SARS-CoV-2 infection.The agreement between theoretical predictions and real data confirms the validity of our approach.

An Experimental Investigation of Auditors' Liability: Implications for Social Welfare and Exploration of Deviations from Theoretical Predictions

2000 ◽  
Vol 75 (4) ◽  
pp. 429-451 ◽  
Author(s):  
Ronald R. King ◽  
Rachel Schwartz
Keyword(s):  
Experimental Investigation ◽  
Social Welfare ◽  
Strict Liability ◽  
Liability Rule ◽  
Optimal Response ◽  
Legal Regimes ◽  
Theoretical Predictions ◽  
Best Responses

This paper reports the results of an experiment designed to investigate how legal regimes affect social welfare. We investigate four legal regimes, each consisting of a liability rule (strict or negligence) and a damage measure (out-of-pocket or independent-of-investment). The results of the experiment are for the most part consistent with the qualitative predictions of Schwartz's (1997) model; however, subjects' actual choices deviate from the point predictions of the model. We explore whether these deviations arise because: (1) subjects form faulty anticipations of their counterparts' actions and/or (2) subjects do not choose the optimal responses given their anticipations. We find that subjects behave differently under the four regimes in terms of anticipation errors and departures from best responses. For example, subjects playing the role of auditors anticipate investments most accurately under the regime with strict liability combined with out-of-pocket damages, but are least likely to choose the optimal response given their anticipations. This finding implies that noneconomic factors likely play a role in determining subjects' choices.

scholarly journals Killing me Softly? Scrutinising the Role of Soft Law in Greece’s Response to COVID-19

2021 ◽  
Vol 12 (1) ◽  
pp. 59-76
Author(s):  
Evangelia (Lilian) TSOURDI ◽  
Niovi VAVOULA
Keyword(s):  
Asylum Seekers ◽  
Personal Data ◽  
Fundamental Rights ◽  
Soft Law ◽  
Freedom Of Movement ◽  
Hard Law ◽  
Primary Basis ◽  
Full Swing ◽  
Second Wave

Greece emerged as the EU’s poster child in the fight against COVID-19 during the first few months of the pandemic. In this contribution, we assess Greece’s use of soft regulation in its regulatory response to COVID-19. Using “acts of legislative content”, which can be broadly conceptualised as softly adopted hard law, the Greek government largely achieved flexibility and simplified adoption procedures without having to resort to soft law per se. The role of soft law was limited - it complemented hard law rather than constituting the primary basis of COVID-19 restrictions - but not completely negligible. Soft law instruments regulated the processing of personal data, and was also pivotal in clarifying the criminal sanctioning of COVID-related rule violations. Greece’s success in handling the first wave of the pandemic, while effective, was arguably unfair to asylum seekers who saw their right to apply for asylum curtailed, and their right to freedom of movement restricted when limitations on the rest of the population were lifted. With a second wave of infections currently in full swing, it is imperative to keep scrutinising regulatory responses to ensure that they place the health and dignity of every individual (whoever they might be) at their core and fully respect their fundamental rights.

scholarly journals Calibrating the CreditRisk+ Model at Different Time Scales and in Presence of Temporal Autocorrelation †

Mathematics ◽  
2021 ◽  
Vol 9 (14) ◽  
pp. 1679
Author(s):  
Jacopo Giacomelli ◽  
Luca Passalacqua
Keyword(s):  
Time Series ◽  
Default Risk ◽  
Real Life ◽  
Statistical Error ◽  
Real Data ◽  
Sampling Period ◽  
Calibration Procedure ◽  
Industry Standards ◽  
Default Rate

The CreditRisk+ model is one of the industry standards for the valuation of default risk in credit loans portfolios. The calibration of CreditRisk+ requires, inter alia, the specification of the parameters describing the structure of dependence among default events. This work addresses the calibration of these parameters. In particular, we study the dependence of the calibration procedure on the sampling period of the default rate time series, that might be different from the time horizon onto which the model is used for forecasting, as it is often the case in real life applications. The case of autocorrelated time series and the role of the statistical error as a function of the time series period are also discussed. The findings of the proposed calibration technique are illustrated with the support of an application to real data.

scholarly journals The Second Wave of COVID-19: Clinical Pharmacy Services During a Field Hospital Operation

2021 ◽  
pp. 001857872110323
Author(s):  
Jessica Mazzone ◽  
Krysta Shannon ◽  
Richard Rovelli ◽  
Racha Kabbani ◽  
Angel Amaral ◽  
...  
Keyword(s):  
Clinical Pharmacy ◽  
The State ◽  
Pharmacy Services ◽  
Newly Diagnosed ◽  
Field Hospital ◽  
Clinical Role ◽  
Diagnosed Diabetes ◽  
Newly Diagnosed Diabetes ◽  
Second Wave

The second wave of COVID-19 emerged in the late fall months in the state of Massachusetts and inadvertently caused a rise in the number of cases requiring hospitalization. With a field hospital previously opened in central Massachusetts during the Spring of 2020, the governor decided to reimplement the field hospital. Although operations were effectively accomplished during the first wave, the reimplementation of the field hospital came with its new set of challenges for operating a satellite pharmacy. Experiences gathered include new pharmacy operation workflows, the clinical role of pharmacy services, introduction of remdesivir treatment, and pharmacy involvement in newly diagnosed diabetes patients requiring insulin teaching. Pharmacy services were successful in adapting to the rapidly growing number in patients with a total of over 600 patients served in a course of 2 months.

The Regional Consequences of the Japanese Second Wave: A Case Study

1995 ◽  
Vol 10 (1) ◽  
pp. 4-20 ◽  
Author(s):  
Max Munday
Keyword(s):  
Local Economy ◽  
The Uk ◽  
Second Wave

Outline This paper examines the Japanese “second wave” sector in the local economy. Following an examination of the development of the second wave Japanese-owned supplier sector in the UK, the paper assesses the role of this sector in the local economy, and questions the policy rationale of attracting this particular type of inward investment.

Prediction of Ball Motion in High-Speed Thrust-Loaded Ball Bearings

1976 ◽  
Vol 98 (3) ◽  
pp. 463-469 ◽  
Author(s):  
C. R. Gentle ◽  
R. J. Boness
Keyword(s):  
Computer Program ◽  
High Speed ◽  
Ball Bearing ◽  
Viscoelastic Behavior ◽  
Specific Situation ◽  
Fluid Models ◽  
Ball Bearings ◽  
Theoretical Predictions ◽  
Ball Motion

This paper describes the development of a computer program used to analyze completely the motion of a ball in a high-speed, thrust-loaded ball bearing. Particular emphasis is paid to the role of the lubricant in governing the forces and moments acting on each ball. Expressions for these forces due to the rolling and sliding of the ball are derived in the light of the latest fluid models, and estimates are also made of the cage forces applicable in this specific situation. It is found that only when lubricant viscoelastic behavior is considered do the theoretical predictions agree with existing experimental evidence.

The role of coinfection with influenza viruses in the pathogenesis of severe infection in patients with COVID-19

2021 ◽  
Vol 21 (3) ◽  
pp. 159-164
Author(s):  
Tamara N. Shvedova ◽  
Olga S. Kopteva ◽  
Polina A. Kudar ◽  
Anna A. Lerner ◽  
Yuliya A. Desheva
Keyword(s):  
Influenza A ◽  
Fold Increase ◽  
Igg Antibodies ◽  
C Reactive Protein ◽  
S Protein ◽  
Neutrophil Lymphocyte Ratio ◽  
Lymphocyte Ratio ◽  
Reactive Protein ◽  
Coronavirus Infection

BACKGROUND: Despite the continuing global spread of the coronavirus infection COVID-19 caused by the SARS-CoV-2 coronavirus, the mechanisms of the pathogenesis of severe infections remain poorly understood. The role of comorbidity with other seasonal viral infections, including influenza, in the pathogenesis of the severe course of COVID-19 remains unclear. MATERIALS AND METHODS: The present study used sera left over from ongoing laboratory studies of patients with varying degrees of severity of COVID-19. The study was approved by the Local Ethics Committee of the Federal State Budgetary Scientific Institution IEM (protocol 3/20 from 06/05/2020). We studied 28 paired samples obtained upon admission of patients to the hospital and after 57 days of hospital stay. Paired sera of patients with COVID-19 were tested for antibodies to influenza A and B viruses. The presence of IgG antibodies specific to the SARS-CoV-2 spike (S) protein was studied using an enzyme-linked immunosorbent assay (ELISA). The serum concentration of C-reactive protein and the neutrophil-lymphocyte ratio on the day of hospitalization were also assessed. RESULTS: At least a 4-fold increase in serum IgG antibodies to SARS-CoV-2 S protein was found both in patients with PCR-confirmed SARS-CoV-2 infection and without PCR confirmation. It was shown that out of 18 patients with moderate and severe forms of COVID-19 infection, six of them showed at least a 4-fold increase in antibodies to influenza A/H1N1, in one to influenza A/H3N2 and in two cases to the influenza B. Laboratory data in these two groups were characterized by significant increases in serum C-reactive protein and neutrophil-lymphocyte ratio concentrations compared with the moderate COVID-19 group. CONCLUSIONS: Serological diagnostics can additionally detect cases of coronavirus infection when the virus was not detected by PCR. In moderate and severe cases of COVID-19, coinfections with influenza A and B viruses have been identified. The results obtained confirm the need for anti-influenza immunization during the SARS-CoV-2 pandemic. Influenza virus screening can significantly improve patient management because recommended antiviral drugs (neuraminidase inhibitors) are available.

The plague in Moscow in 1771 and a new coronavirus infection: what they have in common

2021 ◽  
pp. 62-77
Author(s):  
Leonid Anatolievich Denisov ◽  
Mikhail Sergeevich Pakhomov
Keyword(s):  
Mental Health ◽  
Health Care ◽  
Effective Treatment ◽  
Medical Science ◽  
Historical Event ◽  
Prevention Measures ◽  
Physical And Mental Health ◽  
Coronavirus Infection ◽  
The City

The article is devoted to a historical event that occurred 250 years ago in Moscow. The authors draw analogies between the plague epidemic and the current situation associated with a new coronavirus infection, and note what unites these events. It shows the dedicated work of doctors in the conditions of complete ambiguity of the causes and spread of these infections, in the absence of effective treatment methods, what was the behavior of the population, how prevention measures were developed, and what is the role of the authorities of Moscow and St. Petersburg in the fight. How the state of medical science and the level of health care, referred to by economists as the non — material sphere, can affect the physical and mental health of the population and the economic situation of the city, country and the whole World.

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