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Internet-based behavioral cough suppression therapy for refractory chronic cough : a randomized controlled trial
Salois, Jane R.; Heinle, Kassidi L.; Slovarp, Laurie J.; Jette, Marie E.; Manchaiah, Vinaya; Vlaescu, George; Andersson, Gerhard (American Speech-Language-Hearing Association, 2025-09)
Please read abstract in the article.
A meta-population model of malaria with asymptomatic cases, transmission blocking drugs, migration and screening
Tchoumi, Stephane Yanick; Banasiak, Jacek; Ouifki, R. (AIMS Press, 2025-07-10)
We consider a two-Patch malaria model, where the individuals can freely move between the patches. We assume that one site has better resources to fight the disease, such as screening facilities and the availability of transmission-blocking drugs (TBDs) that offer full, though waning, immunity and non-infectivity. Moreover, individuals moving to this site are screened at the entry points, and the authorities can either refuse entry to infected individuals or allow them in but immediately administer a TBD. However, an illegal entry into this Patch is also possible. We provide a qualitative analysis of the model, focusing on the emergence of endemic equilibria and the occurrence of backward bifurcations. Furthermore, we comprehensively analyse the model with low migration rates using recent refinements of the regular perturbation theory. We conclude the paper with numerical simulations that show, in particular, that malaria can be better controlled by allowing the entry of detected cases and treating them in the better-resourced site rather than deporting the identified infectives and risking them entering the site illegally.
Natural population dynamics of Asian citrus psyllid, Diaphorina citri, and its control based on pheromone trapping
Cardona-Salgado, Daiver; Dumont, Yves; Vasilieva, Olga (Elsevier, 2025-12)
The Asian citrus psyllid (Diaphorina citri) is a major agricultural pest and the principal vector of Huanglongbing (HLB), a devastating citrus disease. Thus, its control is of utmost importance: since D. citri mates multiple times, the use of mating disruption has the potential to reduce or eliminate populations. In this work, we develop a sex-structured, piecewise smooth dynamical system modeling the natural population dynamics of D. citri, focusing on adult stages and mating behavior. The main goal of this manuscript is to show that the population of D. citri, when near a locally asymptotically stable equilibrium, can be effectively suppressed using pheromone traps via two control strategies, mating disruption and male-targeted removal. For this reason, we focus on local stability analysis and the design of practical control interventions that are biologically meaningful and implementable. By applying a feed-forward control approach, which only requires assessing the initial size of the psyllid population, we identify the threshold as a function of the two control parameters above which a local insect elimination is reachable. We also show that a feedback control with periodic assessments of the wild population sizes is applicable, and then deduce that a mixed-type control regime, combining both studied control approaches, yields the best results. We present several simulations to illustrate our theoretical findings and to estimate the minimal amount of pheromones and time needed to reach the local elimination of existing psyllids. Finally, we discuss possible implementations of our results as a part of Integrated Pest Management programs.
Exploring the spatio–temporal dynamics in activator–inhibitor systems through a dual approach of analysis and computation
Chiteri, Vincent Nandwa; Juma, Victor Ogesa; Okwoyo, James Mariita; Moindi, Stephen Kibet; Mapfumo, Kudzanayi Zebedia; Madzvamuse, Anotida (Elsevier, 2025-07)
Real-world mathematical models often manifest as systems of non-linear differential equations, which presents challenges in obtaining closed-form analytical solutions. In this paper, we study the diffusion-driven instability of an activator-inhibitor-type reaction-diffusion (RD) system modeling the GEF-Rho-Myosin signaling pathway linked to cellular contractility. The mathematical model we study is formulated from first principles using experimental observations. The model formulation is based on the biological and mathematical assumptions. The novelty is the incorporation of Myo9b as a GAP for RhoA, leading to a new mathematical model that describes Rho activity dynamics linked to cell contraction dynamics. Assuming mass conservation of molecular species and adopting a quasi-steady state assumption based on biological observations, model reduction is undertaken and leads us to a system of two equations. We adopt a dual approach of mathematical analysis and numerical computations to study the spatiotemporal dynamics of the system. First, in absence of diffusion, we use a combination of phase-plane analysis, numerical bifurcation and simulations to characterize the temporal dynamics of the model. In the absence of spatial variations, we identified two sets of parameters where the model exhibit different transition dynamics. For some set of parameters, the model transitions from stable to oscillatory and back to stable, while for another set, the model dynamics transition from stable to bistable and back to stable dynamics. To study the effect of parameter variation on model solutions, we use partial rank correlation coefficient (PRCC) to characterize the sensitivity of the model steady states with respect to parameters. Second, we extend the analysis of the model by studying conditions under which a uniform steady state becomes unstable in the presence of spatial variations, in a process known as Turing diffusion-driven instability. By exploiting the necessary conditions for diffusion-driven instability and the sufficient conditions for pattern formation we carry out, numerically, parameter estimation through the use of mode isolation. To support theoretical and computational findings, we employ the pdepe solver in one-space dimension and the finite difference method in two-space dimension.
Maternal phenotype, infant size and breast milk composition in women living with HIV
Gilfillan, Marlene; Wenhold, Friedeburg Anna Maria; Mulol, Helen; Feucht, Ute Dagmar (Wiley, 2025-07)
The impact of maternal factors on the size of HIV‐exposed‐uninfected (HEU) infants and breast milk composition is poorly understood. Anthropometry, bio‐electrical impedance, haemoglobin and HIV viral load data of women living with HIV (WLWH) and without HIV (WLWOH) were compared and related to their infants' anthropometric Z‐scores and breast milk macronutrients 6 weeks and 6 months postnatally. At both time points, WLWH (6‐week: n = 83; 6‐month: n = 63) had lower reactance (measure of body cell mass) (6‐week: p = 0.016; 6‐month: p < 0.001), phase angle (PhA) (measure of cell health) (6‐week: p = 0.001; 6‐month: p = 0.002) and haemoglobin (6‐week: p = 0.002; 6‐month: p = 0.004) than WLWOH (6‐week: n = 90; 6‐month: n = 73). HEU infants had lower weight‐for‐age Z‐scores (WAZ) (6‐week: p = 0.010; 6‐month: p = 0.005). Breast milk composition did not differ between groups. At 6 weeks, HEU infants had lower head circumference‐for‐age Z‐scores (HCAZ) (p = 0.014). Bivariate regression demonstrated maternal HIV predicted lower infant WAZ (ß = −0.442; p = 0.011) and HCAZ (ß = −0.445; p = 0.014). Maternal body mass index (BMI) and mid‐upper arm circumference were positively associated with breast milk protein content (ß = 0.018; p = 0.014 and ß = 0.025; p = 0.002, respectively). At 6 months (bivariate regression) maternal HIV predicted lower infant WAZ (ß = −0.609; p = 0.005) and length‐for‐age Z‐scores (ß = −0.741; p = 0.018). Higher maternal BMI and PhA were associated with higher infant WAZ (ß = 0.622; p = 0.015 and ß = 0.055; p = 0.017, respectively). On multivariable analysis, maternal HIV remained a predictor of lower WAZ (ß = −0.568; p = 0.024). In conclusion, maternal HIV infection and phenotype predict the size of infants and breast milk composition up to 6 months postnatally.