Spread Of Contagion Research Articles

Оценка финансового заражения на фьючерсных рынках сельскохозяйственных товаров с помощью корреляционного анализа

Abstract. In the context of financial instability affecting all sectors of the modern economy, an important direction is the study of the effects of contagion – the transmission of instability through different channels between countries, industries and individual economic assets. The purpose of the article was to analyze the comovement of prices for agricultural goods through the study of the relationships of profitability of commodity futures and to obtain on this basis estimates of the scale and direction of financial contagion in food markets. Methods. Advanced methods of correlation analysis were used in the article: correlation coefficients adjusted for heteroscedasticity were determined; the hypothesis of the presence of infection was tested using Forbes – Rigobon test statistics. In addition, based on the calculation of the volatility of commodity futures using the rolling standard deviation method, the time periods necessary to detect infection were distinguished. Scientific novelty. For the first time in Russian practice, an analysis of the effects of financial contagion on the agricultural sector was carried out; quantitative estimates of the scale and direction of infection spreading through internal channels of exchange trade in food products were obtained. Results. A study of the dynamics of prices for some futures for 2003–2022 made it possible to identify periods of increased volatility of commodity markets. It took the highest values in 2008–2009 and 2020–2022 – during these periods, volatility shocks led to the spread of contagion in the futures markets of agricultural commodities. However, the scale of infection was uneven. In the crisis of 2008–2009, 51.8 % of cases of infection were detected, while in 2020–2022 this share was 23.2 %. As for the transmission of infection in paired bundles of the type “commodity-source  commodity-recipient”, most often the sources and recipients were cocoa, coffee and sugar, the least often – soybean meal and lean hogs. In addition, the analysis of paired correlations made it possible to conclude that the predominance of bidirectional contagion.

Assertion, Repetition, Contagion: Generative Mechanisms and Responses to Social Death

Online public opinion gradually evolves into a phenomenon where opinion leaders guide the digital public to commit cyber violence against the public opinion target, eventually leading to the social death of the public opinion target. The role of each opinion subject in the social death of individuals can be analyzed through the mechanisms of assertion, repetition, and contagion transmission proposed by Gustave Le Bon. Opinion makers shape specific events and characters, utilizing assertions to enhance the narrative power and satisfy the psychological image of the media and the public. On this basis, opinion leaders, mainly the media, direct the psychological tendency of the public by spreading assertions more widely through repetition. The participants in public opinion fix assertions on the cross of their moral judgment through the implication of assertion and repetition. Breaking this mechanism requires proprietary measures aimed at the three subjects. First, reduce the power of assertions by identifying ambiguous information and blaming the rumormonger afterward. Second, control the degree of repetition by increasing the responsibility of online media and clarifying effectively. Third, avoid the spread of contagion by improving the quality of Internet users.

Similarity of epidemic spreading and information network connectivity mechanisms demonstrated by analysis of two probabilistic models

<abstract> <p>The modelling of epidemic spreading is essential in understanding the mechanisms of outbreaks and pandemics. Many models for different kinds of spreading have been proposed throughout the history of modelling, each suited for a specific scenario and parameters. On the other hand, models of information networks provide important tools for the analysis of the performance and reliability of such networks. We have previously presented a model for simulating the spreading of infectious disease throughout a social network and another one for simulating the connectivity of data traffic in an information network. We argue that these models are similar in that they produce equivalent results with appropriate parameters when run on the same network. We explain this by reasoning that the manners in which the models carry out their calculations, although devised from different assumptions, turn out to be equivalent. We also show empirical results of applying the models to calculate the spread of contagion and information connectivity on two complex networks suitable for the models. Based on the results, we calculate centrality metrics reflecting the outcome of the application, highlighting its important properties. We note that the centrality values obtained by running the epidemic model and the connectivity model turn out to be mutually equivalent, as predicted by their similar fashions of calculation. As the models were independently developed for their own applications, the equivalence in their calculation can not be explained by the models purposefully built similarly. Thus, not only are the two apparently completely separate areas of interest analysable with a single model but there appear to be inherent similarities in the mechanisms of epidemic spreading and determining network connectivity.</p> </abstract>

Added in Adaptation: The Empire Plays again in the BBC Sherlock Holmes “The Devil’s Foot”

Understanding Sterndale in Conan Doyle’s “The Adventure of the Devil’s Foot” as a foreign threat to the British Empire, critics, especially Susan Cannon Harris and Lauren Raheja, believe that Holmes exiles Sterndale to Africa to prevent the spread of contagion caused by the devil’s foot into the heart of the British Empire. However, going against this view, this paper argues that Sterndale should be viewed as a typical British imperialist; he has been doing his colonial work in Africa as a great lion-hunter and explorer. In addition, Sterndale supports the British Empire by killing Tregennis, who in fact is contaminated and becomes a foreign threat. While this may be slightly difficult to imagine in the fictional representation of the story, the screenplay stresses Sterndale’s imperialism. The BBC adaptation of “The Devil’s Foot,” depicts Sterndale as a British imperialist and Tregennis as the foreign and contaminated threat to the British Empire. In the episode, Sterndale’s cottage is full of exotic African objects, and his collection is reminiscent of the British Museum, a display of Britain’s imperial power. Sterndale is clearly depicted as a typical British imperialist. If this is so, then it is Tregennis, who breaks into Sterndale’s British Museum and kills white British people, who is the foreign threat. Thus, “The Devil’s Foot” screenplay implies that Holmes’s reason for the release of the criminal is to support British imperialism rather an individual’s love story.

APX-hardness and approximation for the k-burning number problem

Consider an information diffusion process on a graph G that starts with k>0 burnt vertices, and at each subsequent step, burns the neighbors of the currently burnt vertices, as well as k other unburnt vertices. The k-burning number of G is the minimum number of steps bk(G) such that all the vertices can be burned within bk(G) steps. Note that the last step may have smaller than k unburnt vertices available, where all of them are burned. The 1-burning number coincides with the well-known burning number problem, which was proposed to model the spread of social contagion. The generalization to k-burning number allows us to examine different worst-case contagion scenarios by varying the spread factor k.In this paper we prove that computing k-burning number is APX-hard, for any fixed constant k. We then give an O((n+m)log⁡n)-time 3-approximation algorithm for computing k-burning number, for any k≥1, where n and m are the number of vertices and edges, respectively. Finally, we show that even if the burning sources are given as an input, computing a burning sequence itself is an NP-hard problem.

Reducing systemic risk in a multi-layer network using reinforcement learning

This paper introduces a novel framework to assess and manage systemic risk in a multi-layer financial network by taking advantage of reinforcement learning (RL). The reduction of systemic risk in the financial network is achieved by applying the deep deterministic policy gradient algorithm (DDPG) to reorganize the interbank lending structure of the network into an orientation that better mitigates the spread of contagion. The reorganization procedure itself was constrained in order to preserve the balance sheet of every bank. To achieve this, we develop a constraint DDPG model consisting of a safety layer coupled with a linear mapping to satisfy the total borrowing and lending amounts of each bank. Moreover, we propose a new multi-layer DebtRank (DR) algorithm taking into account how contagion spreads from one layer to another. Testing against networks of varying size and depth, our DDPG agent was able to reduce systemic risk levels by significant amounts, suggesting the feasibility and utility of employing RL in managing systemic risk through aiding regulatory policy design. We observe an increase in sparsity and an increase in network dissimilarity between the different layers of the network after optimization.

Antiviral Properties of Food Plants could help to Reduce Contagion and Severity in SARS-CoV-2 Infection

Introduction: It is important to find tools to help patients and prevent viral diffusion of pneumonia caused by the 2019 novel coronavirus (2019-nCoV or SARS-CoV-2). Recent articles have reported site-specific SARS-CoV-2 infection on a patient's body, specifically a very active replication in the throat and upper respiratory tract, even at the mild stage of the disease, which shows its efficient viral transmission in sputum. Material and Methods: An alternative that may be feasible is to resort to scientific studies that demonstrate the antiviral potential of medicinal plants species through in-vitro and in-vivo experiments to alleviate symptoms and prevent the spread of contagion. A literature search on Scopus and PubMed on herbs and foods with antiviral properties was performed. Results: This resulted in hundreds of publications showing a diversity of plants with antiviral effects against different virus infections. This article focuses on plants that are of common use, which could act against COVID-19. Conclusions: Herbs and foods with demonstrated antiviral potential have been identified, limiting SARS-CoV-2 spread by interfering with ACE2 protein on infection sites. The analysis of transdisciplinary knowledge allows us to connect previous research on the action of common plants and foods on viruses to limit the replication of SARS-CoV-2 in the throat and upper respiratory tract.

Peer contagion dynamics in the friendships of children with ADHD.

Friendships in middle childhood carry high developmental significance. The majority of children with attention-deficit/hyperactivity disorder (ADHD) have few friendships, unstable friendships, or poor relationship quality in any friendships they have. The current study used time-window sequential analysis to map the dynamics within the friendships of children with ADHD, specifically the peer contagion processes of dyadic mutuality and coercive joining. Participants were 164 dyads consisting of a target child with ADHD and peer problems (age 6-11years; 68% male; and 73% white) and a reciprocated friend. Dyads were observed in the lab during a cooperative task eliciting verbal negotiation processes to decide how to share a limited resource and during a fast-paced, engrossing, and competitive task. Both tasks were designed to mirror the real-world interactions of friends. Sequences of dyadic mutuality (i.e., reciprocity of positive affect and positive behaviors) and coercive joining (i.e., reciprocity of aggressive, controlling, and rule-breaking behaviors) between target children and friends were coded. Regarding dyadic mutuality, target children reciprocated their friends' positive affect in both tasks. They also reciprocated their friends' positive behaviors but only in the cooperative task. In contrast, they only reciprocated their friends' coercive joining behaviors in the competitive task. Medium to large reciprocity effects was found for 36%-53% (dyadic mutuality) and 38%-55% (coercive joining) of target children. These results extend findings of peer contagion processes to the friendships of children with ADHD and suggest that contagion may vary according to interaction context (i.e., competition vs. cooperation). Understanding the spread of peer contagion may illuminate how children with ADHD and their friends influence each other's adjustment over time and may guide friendship-focused psychosocial interventions for this population.

The first baseline of ALDFG generated by the artisanal fishery during the SARS-CoV-2 pandemic on the north coast of Pernambuco, Brazil

To prevent the spread of the COVID-19 contagion, some regions of Brazil implemented a prohibition of beach use, which contributed to a reduction of artisanal fishing activity. This study aimed to evaluate the influence of these beach closures on the incidence of abandoned, lost, or discarded fishing gear (ALDFG) along four beaches located on the northern coast of Pernambuco, Brazil. The absolute and relative frequency of occurrence and the number of observations per unit of effort (OPUE) between the periods before and after the prohibition period were analyzed. A total of 1935 fishing gear residues were found (63% before and 37% after prohibition). There was also a significant reduction in OPUE and in absolute frequency (p < 0.05) between these two periods. Although beach closures appear to have contributed to a reduction in the amount of ALDFG in the region, it does not indicate a complete pause in fishing activities.

Control and Spread of Contagion in Networks with Global Effects

Control and Spread of Contagion in Networks with Global Effects

COVID-19 through a cultural lens

COVID-19 through a cultural lens

The day after tomorrow: financial repercussions of COVID-19 on systemic risk.

In this paper, we study the financial repercussions of COVID-19 and the effect of anti-epidemic measures on financial markets. By using a composite dataset containing stock market indices of 10 countries characterized by heterogeneous levels of contagion, the daily COVID-19 cases and the 108 more restrictive measures implemented to limit the virus from 31/12/2019 to 13/03/2020, we examine the emergence of financial systemic risk, its speed of propagation and the effectiveness of the policies implemented to curb it. On the one hand, the spread of contagion and its transmission on financial markets are investigated via a lagged cross-correlation analysis. Our results show the emergence of systemic risk characterized by a high speed of diffusion. On the other hand, an augmented AR(1)-EGARCH(1,1) model is applied to examine the impact of anti-COVID-19 “policies on financial markets. We show that, regardless of the level of contagion, the restrictive measures are not able to contain the virus-induced investors panic in the first months of the epidemic.

Relationship among state reopening policies, health outcomes and economic recovery through first wave of the COVID-19 pandemic in the U.S.

State governments in the U.S. have been facing difficult decisions involving tradeoffs between economic and health-related outcomes during the COVID-19 pandemic. Despite evidence of the effectiveness of government-mandated restrictions mitigating the spread of contagion, these orders are stigmatized due to undesirable economic consequences. This tradeoff resulted in state governments employing mandates at widely different ways. We compare the different policies states implemented during periods of restriction ("lockdown") and reopening with indicators of COVID-19 spread and consumer card spending at each state during the first "wave" of the pandemic in the U.S. between March and August 2020. We find that while some states enacted reopening decisions when the incidence rate of COVID-19 was minimal or sustained in its relative decline, other states relaxed socioeconomic restrictions near their highest incidence and prevalence rates experienced so far. Nevertheless, all states experienced similar trends in consumer card spending recovery, which was strongly correlated with reopening policies following the lockdowns and relatively independent from COVID-19 incidence rates at the time. Our findings suggest that consumer card spending patterns can be attributed to government mandates rather than COVID-19 incidence in the states. We estimate the recovery in states that reopened in late April was more than the recovery in states that did not reopen in the same period- 15% for consumer card spending and 18% for spending by high income households. This result highlights the important role of state policies in minimizing health impacts while promoting economic recovery and helps planning effective interventions in subsequent waves and immunization efforts.

Plague Time: Space, Fear, and Emergency Statecraft in Early Modern Italy

Michel Foucault argued famously that early modern European governors responded to plague by quarantining entire urban populations and placing citizens under minute surveillance. For Foucault, such sixteenth- and seventeenth-century policies were the first steps towards an authoritarian paradigm that would only emerge in full in the eighteenth century. The present article argues that Foucault’s model is too abstracted to function as a tool for the historical examination of specific emergencies, and it proposes an alternative analytical framework. Addressing itself to actual events in early modern Italy, the article reveals that when plague threatened, Florentine and Bolognese health officials projected themselves into a spatio-temporal dimension in which official actions and perceptions were determined solely by the spread of contagion. This dimension, “plague time,” was not a stage on the irresistible journey towards Foucault’s “utopia of the perfectly governed city.” A contingent response to a recurrent existential menace, plague time rose and fell in response to events, and may be understood as a season.

Otology/Neurotology

Session Description: The COVID-19/SARS-CoV2 pandemic has highlighted concerns regarding disease transmission to both surgeons and assisting staff during procedures that generate droplets and aerosols. Aerosol and droplet formation is known to occur during otologic and lateral skull base surgery, particularly when powered instrumentation is used. This expert panel will review both the basic science and clinical studies regarding risk identification. Recommendations regarding minimization of these risks will be thoroughly discussed in both scientific and practical terms that can be utilized by practicing otolaryngologists in real-life scenarios. In addition, the panel will address controversies regarding these risks and mitigation schemes and address real-life situations using case-based examples relevant to both the general otolaryngologist and neurotologic specialist. The discussion will focus not only on mitigation of spread of SARS-CoV2 virus but also on other currently identified pathogens of the middle ear and mastoid and future threats. This panel will address emerging pathogens that have not yet become threats in the United States and Western Europe but have affected otolaryngologists in other areas of the world. It will also provide guidance for hypothetical novel future threats that have not yet presented in clinical practice. This presentation is highly relevant to practicing otolaryngologists, including general otolaryngologists, pediatric otolaryngologists, and neurotologists and will provide the attendee with a thorough update clinical practice patterns, potential spread of contagion, and strategies of spread mitigation. Outcome Objectives: (1) Examine the basic and clinical science of pathogens of the middle ear, mastoid, and cerebrospinal fluid and the patterns of spread of these pathogens during otologic and lateral skull base procedures. (2) Understand and implement strategies to mitigate spread of currently known pathogens in otologic and lateral skull base procedures, including limitation of the spread of SARS/CoV2. (3) Understand a framework of strategies and best practices for mitigation of spread of emerging pathogens and future pathogens.

Serological prevalence of SARS-CoV-2 infection and associated factors in healthcare workers in a "non-COVID" hospital in Mexico City.

BackgroundMexico is one of the countries with the highest number of deaths from the COVID-19 pandemic. In spite of this high mortality, in Mexico the number of confirmed cases and diagnostic tests per million population are lower than for other comparable countries, which leads to uncertainty about the actual extent of the pandemic. In Mexico City, healthcare workers represent an important fraction of individuals with SARS-CoV-2 infection. We performed a cross-sectional study whose objective was to estimate the frequency of antibodies to SARS-CoV-2 and identify associated factors in healthcare workers at a large hospital in Mexico City.MethodsWe conducted a serological survey in a non-COVID national referral teaching hospital. The study population included all the personnel that works, in any capacity, in the hospital. From this population we selected a representative sample of 300 individuals. Blood samples were collected and questionnaires were applied between August 10th and September 9th, 2020.ResultsELISA results indicate a serological prevalence of SARS-CoV-2 infection of 13.0%. Working in the janitorial and security groups, having an educational level below a university degree, and living with a larger number of people, were all identified as sociodemographic factors that increase the probability of having SARS-CoV-2 infection.ConclusionsLess favored socioeconomic groups face significantly higher prospects of experiencing SARS-CoV-2 infection and in institutions such as ours, providing janitorial and security workgroups with additional testing and counseling could help to limit the spread of contagion. The rate from the official number of confirmed cases in Mexico City is substantially smaller than the seropositive rate identified in this work.

Individual Responsibility as a Protection Measure in Mexico Against the Covid-19

Using a legal philosophy approach, this article seeks to reflect on individual responsibility as a protection measure implemented in Mexico to address the Covid-19 pandemic. The #StayHome strategy is studied as an imperfect legal norm that structures the government's reaction in the country to protect the human right to health of the inhabitants of Mexican territory in the context of the health crisis. Subsequently, the opportunity is considered for the (in)action of individuals under a scheme of individual responsibility in order to avoid the spread of contagion and to have a beneficial impact on the natural process of the epidemic. The conclusion is that despite having an explicit regulatory framework of an executive nature, the Government of Mexico has decided to address the health crisis in terms of reducing infections with a strategy based on two aspects: the first, the socialized measure of #StayAtHome and the second, the transfer of health protection measures to individuals.

School openings and the COVID-19 outbreak in Italy. A provincial-level analysis using the synthetic control method

Schools have been central in the debate about COVID-19. On the one hand, many have argued that they should be kept open, given their importance to youngsters and the future of the country, and the effort many countries have made in establishing protocols to keep them safe. On the other hand, it has been argued that open schools further the spread of the virus, given that these are places with large-scale interaction between teenagers and adults accompanying their children, as well as a major source of congestion on public transportation. We aim to identify the effect of school openings on the spread of COVID-19 contagion. Italy offers an interesting quasi-experimental setting in this regard due to the scattered openings that schools have experienced. By means of a quantitative analysis, employing a synthetic control method approach, we find that Bolzano, the first province in Italy to open schools after the summer break, had far more cases than its synthetic counterfactual, built from a donor pool formed from the other Italian provinces. Results confirm the hypothesis that despite the precautions, opening schools causes an increase in the infection rate, and this must be taken into account by policymakers.

Solvency contagion risk in the Chinese commercial banks’ network

We study a model for solvency contagion risk in financial networks, which allows the spread of contagion to occur before the point of default. This model can quantify systemic contagion loss through stress testing. In the usual case, only the total liabilities and total assets in such a network can be observed. To overcome this problem, we adopt a Gibbs sampling method to generate samples of the interbank liabilities matrix conditioning on the edges. This methodological approach is applied to a Chinese commercial bank network. Our results show that the systemic contagion losses of this network are highly dependent on the perceived exogenous recovery rate, especially when the external shock is strong. In the stress testing, we also analyze solvency contagion losses due to equity and exposure by decomposing the changes in contagion losses from 2008 to 2018 into several individual parts. We find that the contagion losses of the network exhibit a downward trend, indicating a more robust and stable network.

ReCognizing SUspect and PredictiNg ThE SpRead of Contagion Based on Mobile Phone LoCation DaTa (COUNTERACT): A system of identifying COVID-19 infectious and hazardous sites, detecting disease outbreaks based on the internet of things, edge computing, and artificial intelligence

Human movement is a significant factor in extensive spatial-transmission models of contagious viruses. The proposed COUNTERACT system recognizes infectious sites by retrieving location data from a mobile phone device linked with a particular infected subject. The proposed approach is computing an incubation phase for the subject's infection, backpropagation through the subjects’ location data to investigate a location where the subject has been during the incubation period. Classifying to each such site as a contagious site, informing exposed suspects who have been to the contagious location, and seeking near real-time or real-time feedback from suspects to affirm, discard, or improve the recognition of the infectious site. This technique is based on the contraption to gather confirmed infected subject and possibly carrier suspect area location, correlating location for the incubation days. Security and privacy are a specific thing in the present research, and the system is used only through authentication and authorization. The proposed approach is for healthcare officials primarily. It is different from other existing systems where all the subjects have to install the application. The cell phone associated with the global positioning system (GPS) location data is collected from the COVID-19 subjects.