Food web structure and microenvironment affect Chagas disease vector infection and abundance in a rural landscape

Vector-borne pathogen transmission is shaped by multiple abiotic and biotic factors. Understanding the relative importance of these factors on vector abundance and infection is important for developing vector-borne disease control strategies. The crown of the Attalea butyracea palm provides a natural arboreal mesocosm suitable for studying how food web relations and microclimate affect Chagas disease vectors of the genus Rhodnius, which feed on vertebrate blood and interact with many vertebrate and invertebrate species, vegetation, and detritus within the palm crown. We performed a cross-sectional, observational study of A. butyracea crowns using a community ecology network approach to evaluate abiotic and biotic conditions associated with Rhodnius pallescens abundance and infection with Trypanosoma cruzi, the Chagas disease etiologic agent. We collected 1098 R. pallescens from 105 A. butyracea crowns in rural landscapes of Panama. In a palm subset (N = 49), we recorded microclimate and habitat conditions and counted vertebrate and invertebrate species in order to characterize palm crown food webs. We used food web metrics, namely Generality (average number of prey per predator) and Vulnerability (average number of predators per prey) to evaluate associations between palm community trophic structure, vector predators, vector blood meal species composition, vector abundance, and vector T. cruzi infection. Field data analyzed with generalized linear models showed that vector abundance and infection in a given palm crown were influenced by a combination of geographic location, land-use type, palm crown animal community composition, and microhabitat conditions. Vector abundance was negatively associated with increased overall palm crown community diversity. However, vector abundance was positively associated with the invertebrate predator and mammal community. R. pallescens Vulnerability score, which measures predation pressure on the vector within the palm crown, was positively associated with vector abundance. Vector infection with T. cruzi was positively associated with mammal presence; vectors in palms with mammals were about 25 times more likely to be infected with T. cruzi compared with vectors in palms without mammals. Our findings suggest that a holistic study of food webs and environmental variables at the local scale can provide useful information for vector-borne disease management across a wide habitat range

Digital endpoints in clinical trials: emerging themes from a multi-stakeholder Knowledge Exchange event

© The Author(s) 2024. This article is licensed under a Creative Commons Attribution 4.0 International License, to view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Background: Digital technologies, such as wearable devices and smartphone applications (apps), can enable the decentralisation of clinical trials by measuring endpoints in people’s chosen locations rather than in traditional clinical settings. Digital endpoints can allow high-frequency and sensitive measurements of health outcomes compared to visit-based endpoints which provide an episodic snapshot of a person’s health. However, there are underexplored challenges in this emerging space that require interdisciplinary and cross-sector collaboration. A multi-stakeholder Knowledge Exchange event was organised to facilitate conversations across silos within this research ecosystem. Methods: A survey was sent to an initial list of stakeholders to identify potential discussion topics. Additional stakeholders were identified through iterative discussions on perspectives that needed representation. Co-design meetings with attendees were held to discuss the scope, format and ethos of the event. The event itself featured a cross-disciplinary selection of talks, a panel discussion, small-group discussions facilitated via a rolling seating plan and audience participation via Slido. A transcript was generated from the day, which, together with the output from Slido, provided a record of the day’s discussions. Finally, meetings were held following the event to identify the key challenges for digital endpoints which emerged and reflections and recommendations for dissemination. Results: Several challenges for digital endpoints were identified in the following areas: patient adherence and acceptability; algorithms and software for devices; design, analysis and conduct of clinical trials with digital endpoints; the environmental impact of digital endpoints; and the need for ongoing ethical support. Learnings taken for next generation events include the need to include additional stakeholder perspectives, such as those of funders and regulators, and the need for additional resources and facilitation to allow patient and public contributors to engage meaningfully during the event. Conclusions: The event emphasised the importance of consortium building and highlighted the critical role that collaborative, multi-disciplinary, and cross-sector efforts play in driving innovation in research design and strategic partnership building moving forward. This necessitates enhanced recognition by funders to support multi-stakeholder projects with patient involvement, standardised terminology, and the utilisation of open-source software.Peer reviewe

Pulmonary hypertension: intensification and personalization of combination Rx (PHoenix): a phase IV randomized trial for the evaluation of dose‐response and clinical efficacy of riociguat and selexipag using implanted technologies

Approved therapies for the treatment of patients with pulmonary arterial hypertension (PAH) mediate pulmonary vascular vasodilatation by targeting distinct biological pathways. International guidelines recommend that patients with an inadequate response to dual therapy with a phosphodiesterase type‐5 inhibitor (PDE5i) and endothelin receptor antagonist (ERA), are recommended to either intensify oral therapy by adding a selective prostacyclin receptor (IP) agonist (selexipag), or switching from PDE5i to a soluble guanylate‐cyclase stimulator (sGCS; riociguat). The clinical equipoise between these therapeutic choices provides the opportunity for evaluation of individualized therapeutic effects. Traditionally, invasive/hospital‐based investigations are required to comprehensively assess disease severity and demonstrate treatment benefits. Regulatory‐approved, minimally invasive monitors enable equivalent measurements to be obtained while patients are at home. In this 2 × 2 randomized crossover trial, patients with PAH established on guideline‐recommended dual therapy and implanted with CardioMEMS™ (a wireless pulmonary artery sensor) and ConfirmRx™ (an insertable cardiac rhythm monitor), will receive ERA + sGCS, or PDEi + ERA + IP agonist. The study will evaluate clinical efficacy via established clinical investigations and remote monitoring technologies, with remote data relayed through regulatory‐approved online clinical portals. The primary aim will be the change in right ventricular systolic volume measured by magnetic resonance imaging (MRI) from baseline to maximal tolerated dose with each therapy. Using data from MRI and other outcomes, including hemodynamics, physical activity, physiological measurements, quality of life, and side effect reporting, we will determine whether remote technology facilitates early evaluation of clinical efficacy, and investigate intra‐patient efficacy of the two treatment approaches

Marketing as a means to transformative social conflict resolution: lessons from transitioning war economies and the Colombian coffee marketing system

Social conflicts are ubiquitous to the human condition and occur throughout markets, marketing processes, and marketing systems.When unchecked or unmitigated, social conflict can have devastating consequences for consumers, marketers, and societies, especially when conflict escalates to war. In this article, the authors offer a systemic analysis of the Colombian war economy, with its conflicted shadow and coping markets, to show how a growing network of fair-trade coffee actors has played a key role in transitioning the country’s war economy into a peace economy. They particularly draw attention to the sources of conflict in this market and highlight four transition mechanisms — i.e., empowerment, communication, community building and regulation — through which marketers can contribute to peacemaking and thus produce mutually beneficial outcomes for consumers and society. The article concludes with a discussion of implications for marketing theory, practice, and public policy

How Do Employers Use Compensation History?: Evidence from a Field Experiment

We report the results of a field experiment in which treated employers could not observe the compensation history of their job applicants. Treated employers responded by evaluating more applicants, and evaluating those applicants more intensively. They also responded by changing what kind of workers they evaluated: treated employers evaluated workers with 7% lower past average wages and hired workers with 16% lower past average wages. Conditional upon bargaining, workers hired by treated employers struck better wage bargains for themselves. Using a structural model of bidding and hiring, we find that the selection effects we observe would also occur in equilibrium

Optimal process parameters under LINEX loss function with general input quality characteristic

Asymmetric loss function, Taguchi quality model, Gamma distribution, Double exponential distribution, Laplace distribution,

Varian et al Manuscript Data and Code-Food web and microenvironment influence vector-borne disease in Panama

Data collected for Varian et al. manuscript in review Food web structure and microenvironment affect Chagas disease vector infection and abundance in a rural landscape. Includes data collected from palms (Rhodnius pallescens abundance, T. cruzi infection, blood meals, invertebrate and vertebrate genera/species present in palm crowns, palm crown microhabitat, food web metrics) in rural landscapes in Panama under the following approvals and permits: Mi Ambiente: SE/A-93-13, SE/AP-27-16 STRI IACUC: 2013-0601-2016-02, 2016-0801-2019-A1 UGA IACUC: A2016 05-009-R2 IACUC approval 2013-0601-2016-02; 2016-0801-2019-A1</p