scholarly journals Support for the Transmission-Clearance Trade-Off Hypothesis from a Study of Zika Virus Delivered by Mosquito Bite to Mice

Viruses ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1072 ◽  
Author(s):  
Kathryn A. Hanley ◽  
Sasha R. Azar ◽  
Rafael K. Campos ◽  
Nikos Vasilakis ◽  
Shannan L. Rossi
Keyword(s):  
Weight Loss ◽  
Zika Virus ◽  
Neutralizing Antibody ◽  
Instantaneous Rate ◽  
Trade Off ◽  
Virus Dose ◽  
Individual Mouse ◽  
Duration Of Infection ◽  
Empirical Tests ◽  
The Individual

Evolutionary theory indicates that virus virulence is shaped by a trade-off between instantaneous rate of transmission and duration of infection. For most viruses, infection is curtailed by immune clearance, but there are few empirical tests of the transmission–clearance trade-off hypothesis. We exposed A129 mice to bites from groups of 1, 2–4, or 6–9 Aedes albopictus mosquitoes infected with Zika virus (ZIKV). We predicted that a higher number of infectious mosquito bites would deliver a higher total dose of the virus, and that increasing dose would result in earlier onset, higher magnitude, and shorter duration of viremia, as well as a more robust neutralizing antibody response. We found that increases in the number of mosquito bites delivered resulted in significantly different virus replication dynamics with higher, earlier peak titers. All mice experienced a transient weight loss following infection, but the nadir in weight loss was delayed in the mice that received the highest number of bites. Viremia persisted past the period of measurement in this study, so we did not capture its duration. However, the association at the level of the individual mouse between the estimated virus dose delivered and neutralizing antibody titer was remarkably strong, supporting the transmission–clearance trade-off hypothesis.

scholarly journals Single immunization with recombinant ACAM2000 vaccinia viruses expressing the spike and the nucleocapsid proteins protect hamsters against SARS-CoV-2 caused clinical disease

2021 ◽  
Author(s):  
Yvon Deschambault ◽  
Jessie Lynch ◽  
Bryce Warner ◽  
Kevin Tierney ◽  
Denise Huynh ◽  
...  
Keyword(s):  
Weight Loss ◽  
Recovery Time ◽  
Vaccine Candidate ◽  
Neutralizing Antibody ◽  
Spike Protein ◽  
Hamster Model ◽  
Nucleocapsid Proteins ◽  
Viral Loads ◽  
Vaccinia Viruses ◽  
The Individual

SUMMARYIncreasing cases of SARS-CoV-2 breakthrough infections from immunization with predominantly spike protein based COVID-19 vaccines highlight the need for alternative vaccines using different platforms and/or antigens. In this study, we expressed SARS-CoV-2 spike and nucleocapsid proteins in a novel vaccinia virus ACAM2000 platform (rACAM2000). Following a single intramuscular immunization, the rACAM2000 co-expressing the spike and nucleocapsid proteins induced significantly improved protection against SARS-CoV-2 challenge in comparison to rACAM2000 expressing the individual proteins in a hamster model, as shown by reduced weight loss and quicker recovery time. The protection was associated with reduced viral loads, increased neutralizing antibody titre and reduced neutrophil-to-lymphocyte ratio. Thus, our study demonstrates that the rACAM2000 expressing a combination of the spike and nucleocapsid antigens is a promising COVID-19 vaccine candidate and further studies will investigate if the rACAM2000 vaccine candidate can induce a long lasting immunity against infection of SARS-CoV-2 variants of concern.

Exploring the effect of weight loss on food reward at the individual level

2019 ◽  
Author(s):  
Pauline Oustric ◽  
Kristine Beaulieu ◽  
Nuno Casanova ◽  
Francois Husson ◽  
Catherine Gibbons ◽  
...  
Keyword(s):  
Weight Loss ◽  
Food Reward ◽  
Individual Level ◽  
The Individual

Welfare tradeoff psychology is present in children and adults

2018 ◽  
Author(s):  
Rhea M Howard ◽  
Annie C. Spokes ◽  
Samuel A Mehr ◽  
Max Krasnow
Keyword(s):  
Social Networks ◽  
Social Context ◽  
Opportunity Cost ◽  
Trade Off ◽  
Contextual Features ◽  
Limited Experience ◽  
The Individual

Making decisions in a social context often requires weighing one's own wants against the needs and preferences of others. Adults are adept at incorporating multiple contextual features when deciding how to trade off their welfare against another. For example, they are more willing to forgo a resource to benefit friends over strangers (a feature of the individual) or when the opportunity cost of giving up the resource is low (a feature of the situation). When does this capacity emerge in development? In Experiment 1 (N = 208), we assessed the decisions of 4- to 10-year-old children in a picture-based resource tradeoff task to test two questions: (1) When making repeated decisions to either benefit themselves or benefit another person, are children’s choices internally consistent with a particular valuation of that individual? (2) Do children value friends more highly than strangers and enemies? We find that children demonstrate consistent person-specific welfare valuations and value friends more highly than strangers and enemies. In Experiment 2 (N = 200), we tested adults using the same pictorial method. The pattern of results successfully replicated, but adults’ decisions were more consistent than children’s and they expressed more extreme valuations: relative to the children, they valued friends more and valued enemies less. We conclude that despite children’s limited experience allocating resources and navigating complex social networks, they behave like adults in that they reference a stable person-specific valuation when deciding whether to benefit themselves or another and that this rule is modulated by the child’s relationship with the target.

scholarly journals Weighing in on heart failure: the potential impact of bariatric surgery

2021 ◽  
Author(s):  
Tanuka Datta ◽  
Andrew J. Lee ◽  
Rachel Cain ◽  
Melissa McCarey ◽  
David J. Whellan
Keyword(s):  
Heart Failure ◽  
Bariatric Surgery ◽  
Weight Loss ◽  
Cardiovascular System ◽  
Economic Burden ◽  
Treatment Strategies ◽  
It Impacts ◽  
Potential Impact ◽  
The Individual ◽  
Physiologic System

AbstractObesity is a growing worldwide epidemic with significant economic burden that carries with it impacts on every physiologic system including the cardiovascular system. Specifically, the risk of heart failure has been shown to increase dramatically in obese individuals. The purpose of this review is to provide background on the individual burdens of heart failure and obesity, followed by exploring proposed physiologic mechanisms that interconnect these conditions, and furthermore introduce treatment strategies for weight loss focusing on bariatric surgery. Review of the existing literature on patients with obesity and heart failure who have undergone bariatric surgery is presented, compared, and contrasted.

scholarly journals Shared Partisanship, Household Norms and Turnout: Testing a Relational Theory of Electoral Participation

2016 ◽  
Vol 48 (3) ◽  
pp. 807-823 ◽  
Author(s):  
Edward Fieldhouse ◽  
David Cutts
Keyword(s):  
Party Identification ◽  
Household Survey ◽  
Relational Theory ◽  
Civic Duty ◽  
Proposed Model ◽  
The Social ◽  
Empirical Tests ◽  
Partisan Identification ◽  
Consumption Benefits ◽  
The Individual

Previous research shows that the household context is a crucial source of influence on turnout. This article sets out a relational theory of voting in which turnout is dependent on the existence of relational selective consumption benefits. The study provides empirical tests of key elements of the proposed model using household survey data from Great Britain. First, building on expressive theories of voting, it examines the extent to which shared partisan identification enhances turnout. Secondly, extending theories of voting as a social norm, it tests whether the civic norms of citizens’ families or households affect turnout over and above the social norms of the individual. In accordance with expectations of expressive theories of voting, it finds that having a shared party identification with other members of the household increases turnout. It also finds that the civic duty of other household members is important in explaining turnout, even when allowing for respondent’s civic duty.

The Trade‐off Model with Mean Reverting Earnings: Theory and Empirical Tests

2003 ◽  
Vol 113 (490) ◽  
pp. 834-860 ◽  
Author(s):  
Sudipto Sarkar ◽  
Fernando Zapatero
Keyword(s):  
Trade Off ◽  
Empirical Tests

scholarly journals Task allocation and site fidelity jointly influence foraging regulation in honeybee colonies

2017 ◽  
Vol 4 (8) ◽  
pp. 170344 ◽  
Author(s):  
Thiago Mosqueiro ◽  
Chelsea Cook ◽  
Ramon Huerta ◽  
Jürgen Gadau ◽  
Brian Smith ◽  
...  
Keyword(s):  
Site Fidelity ◽  
Collective Behaviour ◽  
Trade Off ◽  
Agent Based ◽  
Resource Collection ◽  
Group Members ◽  
Collective Foraging ◽  
The Individual ◽  
Colony Level ◽  
And Task

Variation in behaviour among group members often impacts collective outcomes. Individuals may vary both in the task that they perform and in the persistence with which they perform each task. Although both the distribution of individuals among tasks and differences among individuals in behavioural persistence can each impact collective behaviour, we do not know if and how they jointly affect collective outcomes. Here, we use a detailed computational model to examine the joint impact of colony-level distribution among tasks and behavioural persistence of individuals, specifically their fidelity to particular resource sites, on the collective trade-off between exploring for new resources and exploiting familiar ones. We developed an agent-based model of foraging honeybees, parametrized by data from five colonies, in which we simulated scouts, who search the environment for new resources, and individuals who are recruited by the scouts to the newly found resources, i.e. recruits. We varied the persistence of returning to a particular food source of both scouts and recruits and found that, for each value of persistence, there is a different optimal ratio of scouts to recruits that maximizes resource collection by the colony. Furthermore, changes to the persistence of scouts induced opposite effects from changes to the persistence of recruits on the collective foraging of the colony. The proportion of scouts that resulted in the most resources collected by the colony decreased as the persistence of recruits increased. However, this optimal proportion of scouts increased as the persistence of scouts increased. Thus, behavioural persistence and task participation can interact to impact a colony's collective behaviour in orthogonal directions. Our work provides new insights and generates new hypotheses into how variations in behaviour at both the individual and colony levels jointly impact the trade-off between exploring for new resources and exploiting familiar ones.

scholarly journals An Empirical Analysis Of The Impact Of Tax Rates On Subchapter S Elections

2011 ◽  
Vol 11 (2) ◽  
pp. 84
Author(s):  
Linda Burilovich
Keyword(s):  
Small Businesses ◽  
Tax Rates ◽  
Corporate Tax ◽  
Double Taxation ◽  
Trade Off ◽  
Taxable Income ◽  
Corporate Form ◽  
Empirical Tests ◽  
The Impact ◽  
Loss Firms

Selecting the appropriate form of organization may be a difficult choice for a small business firm. The corporate form offers legal liability but imposes double taxation. The choice often becomes a trade-off between the nontax benefits of incorporating and the costs of double taxation. Certain small businesses qualify to make an election under Subchapter S of the tax code which allows them to operate as a corporation, but avoid the corporate tax by passing through taxable income or loss to shareholders. These firms are known as S corporations. This article examines the impact of personal and corporate tax rates on the propensity for small businesses to elect to operate as S corporations. The behavior of gain and loss firms is analyzed separately. Empirical tests suggest that tax rates do have a significant and sometimes surprising impact on this choice. These findings have significance for policymakers in attempting to reduce the costs of taxes to new firms which may be inhibited from entering the market due to the impact of double taxation.

scholarly journals Distinct cellular immune signatures in acute Zika virus infection are associated with high or low persisting neutralizing antibody titers

2021 ◽  
Author(s):  
Elizabeth E. McCarthy ◽  
Pamela M. Odorizzi ◽  
Emma Lutz ◽  
Carolyn P. Smullin ◽  
Iliana Tenvooren ◽  
...  
Keyword(s):  
Zika Virus ◽  
Neutralizing Antibodies ◽  
Viral Infections ◽  
Immune Cell ◽  
Acute Infection ◽  
Neutralizing Antibody ◽  
Natural Immunity ◽  
Zikv Infection ◽  
Antibody Titers ◽  
Cellular Immune

Although the formation of a durable neutralizing antibody response after an acute viral infection is a key component of protective immunity, little is known about why some individuals generate high versus low neutralizing antibody titers to infection or vaccination. Infection with Zika virus (ZIKV) during pregnancy can cause devastating fetal outcomes, and efforts to understand natural immunity to this infection are essential for optimizing vaccine design. In this study, we leveraged the high-dimensional single-cell profiling capacity of mass cytometry (CyTOF) to deeply characterize the cellular immune response to acute and convalescent ZIKV infection in a cohort of blood donors in Puerto Rico incidentally found to be viremic during the 2015-2016 epidemic in the Americas. During acute ZIKV infection, we identified widely coordinated responses across innate and adaptive immune cell lineages. High frequencies of multiple activated innate immune subsets, as well as activated follicular helper CD4+ T cells and proliferating CD27-IgD- B cells, during acute infection were associated with high titers of ZIKV neutralizing antibodies at 6 months post-infection. On the other hand, low titers of ZIKV neutralizing antibodies were associated with immune features that suggested a cytotoxic-skewed immune "set-point." Our study offers insight into the cellular coordination of immune responses and identifies candidate cellular biomarkers that may offer predictive value in vaccine efficacy trials for ZIKV and other acute viral infections aimed at inducing high titers of neutralizing antibodies.

Distributed Systems

2020 ◽  
pp. 143-198
Author(s):  
Andreas Bolfing
Keyword(s):  
Distributed Systems ◽  
Fault Tolerant ◽  
Deterministic Algorithm ◽  
Impossibility Result ◽  
Software Systems ◽  
Trade Off ◽  
Byzantine Failures ◽  
The Individual ◽  
Special Case

Chapter 5 considers distributed systems by their properties. The first section studies the classification of software systems, which is usually distinguished in centralized, decentralized and distributed systems. It studies the differences between these three major approaches, showing there is a rather multidimensional classification instead of a linear one. The most important case are distributed systems that enable spreading of computational tasks across several autonomous, independently acting computational entities. A very important result of this case is the CAP theorem that considers the trade-off between consistency, availability and partition tolerance. The last section deals with the possibility to reach consensus in distributed systems, discussing how fault tolerant consensus mechanisms enable mutual agreement among the individual entities in presence of failures. One very special case are so-called Byzantine failures that are discussed in great detail. The main result is the so-called FLP Impossibility Result which states that there is no deterministic algorithm that guarantees solution to the consensus problem in the asynchronous case. The chapter concludes by considering practical solutions that circumvent the impossibility result in order to reach consensus.

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