A sex-structured model with birth pulse and release strategy for the spread of Wolbachia in mosquito population

2018 ◽  
Vol 448 ◽  
pp. 53-65 ◽  
Author(s):  
Yazhi Li ◽  
Xianning Liu
Keyword(s):  
Mosquito Population ◽  
Structured Model ◽  
Birth Pulse ◽  
Release Strategy

scholarly journals Triple-Helix Structured Model Based on Problem-Knowledge-Solution Co-evolution for Innovative Product Design Process

2020 ◽  
Vol 33 (1) ◽  
Author(s):  
Qian Hui ◽  
Yan Li ◽  
Ye Tao ◽  
Hongwei Liu
Keyword(s):  
Product Design ◽  
Design Process ◽  
Design Problem ◽  
Triple Helix ◽  
Problem Solution ◽  
Innovative Product ◽  
Innovative Design ◽  
Structured Model ◽  
Knowledge Spaces ◽  
Product Design Process

AbstractA design problem with deficient information is generally described as wicked or ill-defined. The information insufficiency leaves designers with loose settings, free environments, and a lack of strict boundaries, which provides them with more opportunities to facilitate innovation. Therefore, to capture the opportunity behind the uncertainty of a design problem, this study models an innovative design as a composite solving process, where the problem is clarified and resolved from fuzziness to satisfying solutions by interplay among design problems, knowledge, and solutions. Additionally, a triple-helix structured model for the innovative product design process is proposed based on the co-evolution of the problem, solution, and knowledge spaces, to provide designers with a distinct design strategy and method for innovative design. The three spaces interact and co-evolve through iterative mappings, including problem structuring, knowledge expansion, and solution generation. The mappings carry the information processing and decision-making activities of the design, and create the path to satisfying solutions. Finally, a case study of a reactor coolant flow distribution device is presented to demonstrate the practicability of this model and the method for innovative product design.

scholarly journals OP0198-HPR A STRUCTURED MODEL FOR OA CARE IN PRIMARY HEALTHCARE IS A COST-EFFECTIVE ALTERNATIVE COMPARED TO USUAL CARE FOR PEOPLE WITH HIP AND KNEE OA

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 119-120
Author(s):  
N. Østerås ◽  
E. Aas ◽  
T. Moseng ◽  
L. Van Bodegom-Vos ◽  
K. Dziedzic ◽  
...  
Keyword(s):  
Usual Care ◽  
Primary Healthcare ◽  
Intervention Group ◽  
Cost Effective ◽  
Cost Utility ◽  
Control Group ◽  
Structured Model ◽  
Knee Oa ◽  
Cost Effective Alternative ◽  
The Cost

Background:To improve quality of care for patients with hip and knee osteoarthritis (OA), a structured model for integrated OA care was developed based on international treatment recommendations. A previous analysis of a cluster RCT (cRCT) showed that compared to usual care, the intervention group reported higher quality of care and greater satisfaction with care. Also, more patients were treated according to international guidelines and fulfilled recommendations for physical activity at the 6-month follow-up.Objectives:To assess the cost-utility of a structured model for hip or knee OA care.Methods:A cRCT with stepped-wedge cohort design was conducted in 6 Norwegian municipalities (clusters) in 2015-17. The OA care model was implemented in one cluster at the time by switching from “usual care” to the structured model. The implementation of the model was facilitated by interactive workshops for general practitioners (GPs) and physiotherapists (PTs) with an update on OA treatment recommendations. The GPs explained the OA diagnosis and treatment alternatives, provided pharmacological treatment when appropriate, and suggested referral to physiotherapy. The PT-led patient OA education programme was group-based and lasted 3 hours followed by an 8–12-week individually tailored resistance exercise programme with twice weekly 1-hour supervised group sessions (5–10 patients per PT). An optional 10-hours Healthy Eating Program was available. Participants were ≥45 years with symptomatic hip or knee OA.Costs were measured from the healthcare perspective and collected from several sources. Patients self-reported visits in primary healthcare at 3, 6, 9 and 12 months. Secondary healthcare visits and joint surgery data were extracted from the Norwegian Patient Register. The health outcome, quality-adjusted life-year (QALY), was estimated based on the EQ-5D-5L scores at baseline, 3, 6, 9 and 12 months. The result of the cost-utility analysis was reported using the incremental cost-effectiveness ratio (ICER), defined as the incremental costs relative to incremental QALYs (QALYs gained). Based on Norwegian guidelines, the threshold is €27500. Sensitivity analyses were performed using bootstrapping to assess the robustness of reported results and presented in a cost-effectiveness plane (Figure 1).Results:The 393 patients’ mean age was 63 years (SD 9.6) and 74% were women. 109 patients were recruited during control periods (control group), and 284 patients were recruited during interventions periods (intervention group). Only the intervention group had a significant increase in EQ-5D-5L utility scores from baseline to 12 months follow-up (mean change 0.03; 95% CI 0.01, 0.05) with QALYs gained: 0.02 (95% CI -0.08, 0.12). The structured OA model cost approx. €301 p.p. with an additional €50 for the Healthy Eating Program. Total 12 months healthcare cost p.p. was €1281 in the intervention and €3147 in the control group, resulting in an incremental cost of -€1866 (95% CI -3147, -584) p.p. Costs related to surgical procedures had the largest impact on total healthcare costs in both groups. During the 12-months follow-up period, 5% (n=14) in the intervention compared to 12% (n=13) in the control group underwent joint surgery; resulting in a mean surgical procedure cost of €553 p.p. in the intervention as compared to €1624 p.p. in the control group. The ICER was -€93300, indicating that the OA care model resulted in QALYs gained and cost-savings. At a threshold of €27500, it is 99% likely that the OA care model is a cost-effective alternative.Conclusion:The results of the cost-utility analysis show that implementing a structured model for OA care in primary healthcare based on international guidelines is highly likely a cost-effective alternative compared to usual care for people with hip and knee OA. More studies are needed to confirm this finding, but this study results indicate that implementing structured OA care models in primary healthcare may be beneficial for the individual as well as for the society.Disclosure of Interests:None declared

scholarly journals Influence of competition and intraguild predation between two candidate biocontrol parasitoids on their potential impact against Harrisia cactus mealybug, Hypogeococcus sp. (Hemiptera: Pseudococcidae)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
María B. Aguirre ◽  
Octavio A. Bruzzone ◽  
Serguei V. Triapitsyn ◽  
Hilda Diaz-Soltero ◽  
Stephen D. Hight ◽  
...  
Keyword(s):  
Intraguild Predation ◽  
Interference Competition ◽  
Biocontrol Agents ◽  
Parasitoid Species ◽  
Temporal Window ◽  
Response Models ◽  
Potential Impact ◽  
Functional Response Models ◽  
Fully Bayesian ◽  
Release Strategy

AbstractWhen two or more parasitoid species, particularly candidates for biocontrol, share the same target in the same temporal window, a complex of behaviors can occur among them. We studied the type of interactions (competition and intraguild predation) that existed between the nymphal parasitoids Anagyrus cachamai and A. lapachosus (Hymenoptera: Encyrtidae), two candidate neoclassical biocontrol agents against the Puerto Rican cactus pest mealybug, Hypogeococcus sp. (Hemiptera: Pseudococcidae). The surrogate native congener host in Argentina, the cactus mealybug Hypogeococcus sp., was studied to predict which species should be released; in the case that both should be released, in which order, and their potential impact on host suppression. In the laboratory we conducted experiments where different densities of the host mealybug were exposed to naive females of A. cachamai and A. lapachosus sequentially in both directions. Experiments were analyzed by combining a series of competitive behavioral and functional response models. A fully Bayesian approach was used to select the best explaining models and calculate their parameters. Intraguild predation existed between A. cachamai, the species that had the greatest ability to exploit the resource, and A. lapachosus, the strongest species in the interference competition. The role that intraguild predation played in suppression of Hypogeococcus sp. indicated that a multiple release strategy for the two biocontrol agents would produce better control than a single release; as for the release order, A. lapachosus should be released first.

scholarly journals Prehospital emergency medical technicians can perform ultrasonography and blood analysis in prehospital evaluation of patients with chronic obstructive pulmonary disease: a feasibility study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Giti Nadim ◽  
Christian B. Laursen ◽  
Pia I. Pietersen ◽  
Daniel Wittrock ◽  
Michael K. Sørensen ◽  
...  
Keyword(s):  
Chronic Obstructive Pulmonary Disease ◽  
Pulmonary Disease ◽  
Respiratory Insufficiency ◽  
Emergency Departments ◽  
Emergency Medical Technicians ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Emergency Medical ◽  
Short Period ◽  
Release Strategy

Abstract Introduction Crowding of the emergency departments is an increasing problem. Many patients with an exacerbation of chronic obstructive pulmonary disease (COPD) are often treated in the emergency departments for a very short period before discharged to their homes. It is possible that this treatment could take place in the patients’ homes with sufficient diagnostics supporting the treatment. In an effort to keep the diagnostics and treatment of some of these patients in their homes and thus to reduce the patient load at the emergency departments, we implemented a prehospital treat-and-release strategy based on ultrasonography and blood testing performed by emergency medical technicians (EMT) or paramedics (PM) in patients with acute exacerbation of COPD. Method EMTs and PMs were enrolled in a six-hour educational program covering ultrasonography of the lungs and point of care blood tests. During the seasonal peak of COPD exacerbations (October 2018 – May 2019) all patients who were treated by the ambulance crews for respiratory insufficiency were screened in the ambulances. If the patient had uncomplicated COPD not requiring immediate transport to the hospital, ultrasonographic examination of the lungs, measurements of C-reactive protein and venous blood gases analyses were performed. The response to the initial treatment and the results obtained were discussed via telemedical consultation with a prehospital anaesthesiologist who then decided to either release the patient at the scene or to have the patient transported to the hospital. The primary outcome was strategy feasibility. Results We included 100 EMTs and PMs in the study. During the study period, 771 patients with respiratory insufficiency were screened. Uncomplicated COPD was rare as only 41patients were treated according to the treat-and-release strategy. Twenty of these patients (49%) were released at the scene. In further ten patients, technical problems were encountered hindering release at the scene. Conclusion In a few selected patients with suspected acute exacerbations of COPD, it was technically and organisationally feasible for EMTs and PMs to perform prehospital POCT-ultrasound and laboratory testing and release the patients following treatment. None of the patients released at the scene requested a secondary ambulance within the first 48 h following the intervention.

scholarly journals Minimizing Potential Allee Effects in Psittacine Reintroductions: An Example from Puerto Rico

Diversity ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 13
Author(s):  
Thomas H. White ◽  
Wilfredo Abreu ◽  
Gabriel Benitez ◽  
Arelis Jhonson ◽  
Marisel Lopez ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Site Fidelity ◽  
Conservation Strategies ◽  
Allee Effects ◽  
Species Reintroduction ◽  
Social Species ◽  
Potential Applicability ◽  
Amazona Vittata ◽  
Puerto Rican Parrot ◽  
Release Strategy

The family Psittacidae is comprised of over 400 species, an ever-increasing number of which are considered threatened with extinction. In recent decades, conservation strategies for these species have increasingly employed reintroduction as a technique for reestablishing populations in previously extirpated areas. Because most Psittacines are highly social and flocking species, reintroduction efforts may face the numerical and methodological challenge of overcoming initial Allee effects during the critical establishment phase of the reintroduction. These Allee effects can result from failures to achieve adequate site fidelity, survival and flock cohesion of released individuals, thus jeopardizing the success of the reintroduction. Over the past 20 years, efforts to reestablish and augment populations of the critically endangered Puerto Rican parrot (Amazona vittata) have periodically faced the challenge of apparent Allee effects. These challenges have been mitigated via a novel release strategy designed to promote site fidelity, flock cohesion and rapid reproduction of released parrots. Efforts to date have resulted in not only the reestablishment of an additional wild population in Puerto Rico, but also the reestablishment of the species in the El Yunque National Forest following its extirpation there by the Category 5 hurricane Maria in 2017. This promising release strategy has potential applicability in reintroductions of other psittacines and highly social species in general.

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