scholarly journals Pervasive Resistance to Pyrethroids in German Cockroaches (Blattodea: Ectobiidae) Related to Lack of Efficacy of Total Release Foggers

2019 ◽  
Vol 112 (5) ◽  
pp. 2295-2301 ◽  
Author(s):  
Zachary C DeVries ◽  
Richard G Santangelo ◽  
Jonathan Crissman ◽  
Alonso Suazo ◽  
Madhavi L Kakumanu ◽  
...  
Keyword(s):  
Active Ingredient ◽  
Pyrethroid Resistance ◽  
Low Cost ◽  
Population Based ◽  
Susceptible Population ◽  
Limited Efficacy ◽  
Metabolic Detoxification ◽  
Do It Yourself ◽  
High Doses ◽  
Cockroach Blattella Germanica

Abstract Despite limited efficacy data, do-it-yourself (DIY) insecticide products often promise low-cost alternatives to professional pest control. Total release foggers (TRFs, ‘bug bombs’), which are prominent DIY products, were recently shown to be ineffective at reducing German cockroach (Blattella germanica L.) infestations, in contrast to highly effective baits. However, the reason(s) for TRF failure remain unknown. Therefore, we investigated insecticide resistance of apartment-collected cockroaches from homes where TRFs failed. In topical (direct) application assays, resistance to cypermethrin (a common active ingredient in TRFs) was 202 ± 33 times that of a laboratory insecticide-susceptible population (based on LD50 ratios), while resistance to fipronil, a common bait active ingredient, was considerably lower at 14 ± 2 times that of the laboratory insecticide-susceptible population. The addition of PBO, a P450 inhibitor that synergizes pyrethroids, enhanced the efficacy of cypermethrin, but only at high doses of cypermethrin. Additionally, >96% of screened cockroaches possessed at least one copy of the L993F mutation in the voltage-gated sodium channel, known to confer resistance to pyrethroids (knockdown resistance, kdr). Because TRF treatments killed insecticide-susceptible sentinel cockroaches but failed to kill apartment-collected cockroaches, these results suggest that pyrethroid resistance is a major factor contributing to the failure of TRFs. Multiple mechanisms of resistance, including metabolic detoxification of the pyrethroids and kdr mutations that confer target-site insensitivity, suggest that TRFs would lack efficacy against German cockroaches in residential settings, where high levels of pyrethroid resistance have been documented globally.

scholarly journals A Framework for a New Approach to Empower Users Through Low-Cost and Do-It-Yourself Assistive Technology

2021 ◽  
Vol 18 (6) ◽  
pp. 3039
Author(s):  
Thais Pousada García ◽  
Jessica Garabal-Barbeira ◽  
Patricia Porto Trillo ◽  
Olalla Vilar Figueira ◽  
Cristina Novo Díaz ◽  
...  
Keyword(s):  
Assistive Technology ◽  
Outcome Measures ◽  
Design Thinking ◽  
Low Cost ◽  
Well Being ◽  
Pilot Project ◽  
Assistive Device ◽  
Preliminary Results ◽  
Do It Yourself ◽  
Principles Of Design

Background: Assistive Technology (AT) refers to “assistive products and related systems and services developed for people to maintain or improve functioning and thereby to promote well-being”. Improving the process of design and creation of assistive products is an important step towards strengthening AT provision. Purpose: (1) to present a framework for designing and creating Low-Cost AT; (2) to display the preliminary results and evidence derived from applying the framework. Methodology: First, an evidence-based process was applied to develop and conceptualize the framework. Then, a pilot project to validate the framework was carried out. The sample was formed by 11 people with disabilities. The measure instruments were specific questionnaire, several forms of the Matching Person-Technology model, the Psychosocial Impact of Assistive Device Scale, and a tool to assess the usability and universal design of AT. Results: The framework integrates three phases: Identification (Design), Creation (Making the prototype), and Implementation (Outcome Measures), based on the principles of Design Thinking, and with a user-centered perspective. The preliminary results showed the coherence of the entire process and its applicability. The matching between person and device was high, representing the importance of involving the user in the design and selection of AT. Conclusions: The framework is a guide for professionals and users to apply a Low-Cost and Do-It-Yourself perspective to the provision of AT. It highlights the importance of monitoring the entire procedure and measuring the effects, by applying the outcome measures.

Insecticide Resistance Patterns and Mechanisms in Aedes aegypti (Diptera: Culicidae) Populations Across Abidjan, Côte d’Ivoire Reveal Emergent Pyrethroid Resistance

2021 ◽  
Author(s):  
Lucien Yao Konan ◽  
Welbeck Achille Oumbouke ◽  
Urbain Garhapié Silué ◽  
Ibrahima Zanakoungo Coulibaly ◽  
Jean-Claude Tokou Ziogba ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Pyrethroid Resistance ◽  
Population Based ◽  
Cote D’Ivoire ◽  
Low Frequencies ◽  
Larval Habitats ◽  
Côte D'ivoire ◽  
The City

Abstract From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epidemics which required control of the vector mosquito population based on the reduction of larval habitats and insecticidal sprays for adult mosquitoes. This study was undertaken to assess the insecticide susceptibility status of Aedes aegypti (Linnaeus) in the city of Abidjan. Immature Ae. aegypti were sampled from several larval habitats within seven communes of Abidjan and reared to adults. Three to five days old F1 emerged adults were tested for susceptibility using insecticide-impregnated papers and the synergist piperonyl butoxide (PBO) following WHO bioassay guidelines. The results showed that Ae. aegypti populations from Abidjan were resistant to 0.1% propoxur, and 1% fenitrothion, with mortality rates ranging from 0% to 54.2%. Reduced susceptibility (93.4–97.5% mortality) was observed to 0.05% deltamethrin, 0.75% permethrin, 0.05% lambda-cyhalothrin, 5% malathion, and 0.8% chlorpyrifos-methyl. This reduced susceptibility varied depending on the insecticide and the collection site. The restoration of mortality when the mosquitoes were pre-exposed to the synergist PBO suggests that increased activity of oxidases could be contributing to resistance. Three kdr mutations (V410L, V1016I, and F1534C) were present in populations tested, with low frequencies for the Leu410 (0.28) and Ile1016 (0.32) alleles and high frequencies for the Cys1534 allele (0.96). These findings will be used to inform future arbovirus vector control activities in Abidjan.

scholarly journals Mask R-CNN Based C. Elegans Detection with a DIY Microscope

Biosensors ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 257
Author(s):  
Sebastian Fudickar ◽  
Eike Jannik Nustede ◽  
Eike Dreyer ◽  
Julia Bornhorst
Keyword(s):  
Cell Biology ◽  
High Throughput Screening ◽  
Low Cost ◽  
Image Acquisition ◽  
Rapid Development ◽  
Model Organism ◽  
Large Data ◽  
Data Set ◽  
C Elegans ◽  
Do It Yourself

Caenorhabditis elegans (C. elegans) is an important model organism for studying molecular genetics, developmental biology, neuroscience, and cell biology. Advantages of the model organism include its rapid development and aging, easy cultivation, and genetic tractability. C. elegans has been proven to be a well-suited model to study toxicity with identified toxic compounds closely matching those observed in mammals. For phenotypic screening, especially the worm number and the locomotion are of central importance. Traditional methods such as human counting or analyzing high-resolution microscope images are time-consuming and rather low throughput. The article explores the feasibility of low-cost, low-resolution do-it-yourself microscopes for image acquisition and automated evaluation by deep learning methods to reduce cost and allow high-throughput screening strategies. An image acquisition system is proposed within these constraints and used to create a large data-set of whole Petri dishes containing C. elegans. By utilizing the object detection framework Mask R-CNN, the nematodes are located, classified, and their contours predicted. The system has a precision of 0.96 and a recall of 0.956, resulting in an F1-Score of 0.958. Considering only correctly located C. elegans with an [email protected] IoU, the system achieved an average precision of 0.902 and a corresponding F1 Score of 0.906.

Development of Bioimpedance Sensors and Measurement System for Biomedical In-Vitro Applications

2021 ◽  
Vol 7 (2) ◽  
pp. 496-499
Author(s):  
Stadler B. Eng. Sebastian ◽  
Herbert Plischke ◽  
Christian Hanshans
Keyword(s):  
Measurement System ◽  
Low Cost ◽  
Measurement Data ◽  
Impedance Measurement ◽  
Microtiter Plate ◽  
Label Free ◽  
Single Chip ◽  
Do It Yourself ◽  
Store And Forward

Abstract Bioimpedance analysis is a label-free and easy approach to obtain information on cellular barrier integrity and cell viability more broadly. In this work, we introduce a small, low-cost, portable in vitro impedance measurement system for studies where a shadow-free exposure of the cells is a requirement. It can be controlled by a user-friendly web interface and can perform measurements automated and autonomously at short intervals. The system can be integrated into an existing IoT network for remote monitoring and indepth analyses. A single-board computer (SBC) serves as the central unit, to control, analyze, store and forward the measurement data from the single-chip impedance analyzer. Various materials and manufacturing methods were used to produce a purpose-built lid on top of a modified 24-well microtiter plate in a “do it yourself” fashion. Furthermore, three different sensor designs were developed utilizing anodic aluminum oxide (AAO) membranes and gold-plated electrodes. Preliminary tests with potassium chloride (KCl) showed first promising results.

Acceptability of a School-Based Intervention for the Prevention of Adolescent Obesity

2006 ◽  
Vol 22 (5) ◽  
pp. 269-277 ◽  
Author(s):  
Leanne M. Mauriello ◽  
Mary Margaret H. Driskell ◽  
Karen J. Sherman ◽  
Sara S. Johnson ◽  
Janice M. Prochaska ◽  
...  
Keyword(s):  
Transtheoretical Model ◽  
Fruits And Vegetables ◽  
School Administrators ◽  
Low Cost ◽  
Population Based ◽  
Student Responses ◽  
School Based Intervention ◽  
School Based ◽  
Computer Based ◽  
Obesity Prevention Program

This article describes the development and pilot testing of a computer-based, multiple-behavior obesity prevention program for adolescents. Using the Transtheoretical Model as a framework, this intervention offers individualized feedback based on readiness to engage in physical activity, to consume fruits and vegetables, and to limit television viewing. Focus groups and interviews with students, teachers, school administrators, and experts guided the development. Forty-five students participated in a baseline intervention session and completed a 16-item acceptability measure. Ratings were positive, with item means ranging from 3.60–4.75 on a 5-point scale. Student responses to open-ended questions aided in the enhancement of the intervention, for which an effectiveness trial begins in September 2006. This formative work demonstrated the acceptability of this school-based intervention approach, which can be promoted and prescribed by school nurses. Further, if found effective, it can be disseminated as an efficient, low-cost, population-based approach designed to address the epidemic of obesity.

scholarly journals Identifying Current and Missing Knowledge in the Control of Pyrethroid-Resistant Triatoma infestans, Vector of Chagas Disease

2017 ◽  
Vol 9 (7) ◽  
pp. 47
Author(s):  
Gonzalo Roca Acevedo ◽  
María Inés Picollo
Keyword(s):  
Chagas Disease ◽  
Chemical Control ◽  
Rational Design ◽  
Pyrethroid Resistance ◽  
Triatoma Infestans ◽  
Vector Transmission ◽  
Pyrethroid Insecticides ◽  
Blood Sucking ◽  
Deltamethrin Resistance ◽  
Metabolic Detoxification

Triatomines are blood-sucking bugs that occur mainly in Latin America. They are vectors of Trypanosoma cruzi, the parasite that causes Chagas disease. Chemical control of Chagas disease´s vectors by using pyrethroid insecticides has been highly successful for the elimination of domestic infestation and consequently the reduction of the vector transmission. However, at the beginning of the 2000s a decrease in the effectiveness of the chemical control of triatomines was detected in several areas from Argentina and Bolivia, particularly in the Gran Chaco eco-region.During the last 15 years, several studies demonstrated the evolution of insecticide resistance in Triatoma infestans and established the presence of different toxicological profiles, the autosomal inherence of resistance, the biological costs of deltamethrin resistance, the expression of deltamethrin resistance thorough the embryonic development, and the main mechanisms of resistance (target-site insensitivity and metabolic detoxification of insecticides).The emergence of pyrethroid resistance coupled with the usual difficulties in sustaining adequate rates of insecticide applications emphasize the need of incorporating other tools for integrated vector and disease control, such as the proposal of the organo-phosphorus insecticide fenitrothion as an alternative chemical strategy for the management of the resistance because it was effective against pyrethroid-resistant populations in laboratory and semi-field trials.New studies on the current situation of presence and spread of resistant populations of triatomines and the acceptance of the use of alternative insecticides are critical requirements in the implementation of strategies for the management of resistance and for the rational design of campaigns oriented to reducing the vector transmission of Chagas’ disease.

scholarly journals Personalized Hypertension Management Based on Serial Assessment and Telemedicine: a Cluster Randomize Controlled Trial Protocol in Anhui, China

2020 ◽  
Author(s):  
Siyi Xiao ◽  
Xingrong Shen ◽  
Rong Liu ◽  
Guixian Tong ◽  
Tongzhu Liu ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Low Cost ◽  
Controlled Trial ◽  
Population Based ◽  
Future Research ◽  
Hypertension Management ◽  
Intervention Package ◽  
Self Monitoring ◽  
Intervention Measures ◽  
Cluster Randomized

Abstract Background: Despite tremendous investment worldwide, hypertension treatment and control rates remain low, suggesting that contemporary population-based hypertension management may have reached its efficacy ceiling. The complexity and long-term dynamics of influencing factors make personalized management inevitable and challenging. This protocol describes Personalized Hypertension Management in Anhui, China (PHMA), a project that uses a package of innovative approaches in tailoring interventions to individual patient’s dynamic complications and contexts.Methods/design: PHMA strives to reduce hypertension harms by eight proven “objective behaviors” (e.g., self-monitoring and reporting, healthy diet, physical exercise/activities). These objective behaviors are promoted through five intervention measures: support for self- monitoring, supervised machine communications, daily education or reminder messages, weekly blood pressure notification, and quarterly signed feedback. PHMA uses ten categories and over 300 variables in selecting and refining intervention procedures and content for individual patients. Efficacy of the intervention package is evaluated using a cluster randomized controlled trial design involving a total of 60 site communities and 3352 hypertension patients. Primary measure for the evaluation is systolic and diastolic blood pressure; while secondary evaluation measures include quality of life (EQ5D-5L), occurrence of hypertension-related complications (such as cerebral hemorrhage, coronary heart disease, myocardial or cerebral infarction), healthcare utilization and scores of objective behaviors.Discussion: PHMA uses novel, low cost and sustainable approaches to tailor interventions to the dynamic conditions and contexts of individual patients. Unlike contemporary approaches to hypertension management which are mainly population based, each participant patient in PHMA applies a unique intervention package and all messages, feedbacks and other materials sent out to individual patients are different from each other. PHMA is the first project that adopts so comprehensive tailoring and if proved effective, it should have important implications for future research, practice and policy-making.Trial registration: Registered July 17, 2020. ISRCTN10999269.

scholarly journals A DIY Fabrication Approach for Ultra-Thin Focus-Tunable Liquid Lens Using Electrohydrodynamic Pump

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1452
Author(s):  
Taichi Murakami ◽  
Yu Kuwajima ◽  
Ardi Wiranata ◽  
Ayato Minaminosono ◽  
Hiroki Shigemune ◽  
...  
Keyword(s):  
Low Cost ◽  
Rapid Development ◽  
Pure Water ◽  
Dielectric Fluid ◽  
Copper Sheet ◽  
Fluidic Channel ◽  
Liquid Lens ◽  
Do It Yourself ◽  
Tunable Lenses ◽  
Smart Mobile

Demand for variable focus lens is increasing these days due to the rapid development of smart mobile devices and drones. However, conventional mechanical systems for lenses are generally complex, cumbersome, and rigid (e.g., for motors and gears). This research proposes a simple and compact liquid lens controlled by an electro hydro dynamics (EHD) pump. In our study, we propose a do-it-yourself (DIY) method to fabricate the low-cost EHD lens. The EHD lens consists of a polypropylene (PP) sheet for the exterior, a copper sheet for the electrodes, and an acrylic elastomer for the fluidic channel where dielectric fluid and pure water are filled. We controlled the lens magnification by changing the curvature of the liquid interface between the dielectric fluid and pure water. We evaluated the magnification performance of the lens. Moreover, we also established a numerical model to characterize the lens performance. We expect to contribute to the miniaturization of focus-tunable lenses.

scholarly journals Optimization of a Handwriting Method by an Automated Ink Pen for Cost-Effective and Sustainable Sensors

Chemosensors ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 264
Author(s):  
Florin C. Loghin ◽  
José F. Salmerón ◽  
Paolo Lugli ◽  
Markus Becherer ◽  
Aniello Falco ◽  
...  
Keyword(s):  
Printed Electronics ◽  
Low Cost ◽  
Electronic Devices ◽  
Cost Effective ◽  
Capacitive Sensor ◽  
Fabrication Technique ◽  
Rfid Tag ◽  
Environmental Friendly ◽  
Fast Prototyping ◽  
Do It Yourself

In this work, we present a do-it-yourself (DIY) approach for the environmental-friendly fabrication of printed electronic devices and sensors. The setup consists only of an automated handwriting robot and pens filled with silver conductive inks. Here, we thoroughly studied the fabrication technique and different optimized parameters. The best-achieved results were 300 mΩ/sq as sheet resistance with a printing resolution of 200 µm. The optimized parameters were used to manufacture fully functional electronics devices: a capacitive sensor and a RFID tag, essential for the remote reading of the measurements. This technique for printed electronics represents an alternative for fast-prototyping and ultra-low-cost fabrication because of both the cheap equipment required and the minimal waste of materials, which is especially interesting for the development of cost-effective sensors.

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