scholarly journals A low-cost repellent for malaria vectors in the Americas: results of two field trials in Guatemala and Peru

2007 ◽  
Vol 6 (1) ◽  
pp. 101 ◽  
Author(s):  
Sarah J Moore ◽  
Samuel T Darling ◽  
Moisés Sihuincha ◽  
Norma Padilla ◽  
Gregor J Devine
Keyword(s):  
Low Cost ◽  
Field Trials ◽  
Malaria Vectors

scholarly journals Eave ribbons treated with transfluthrin can protect both users and non-users against malaria vectors

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Emmanuel P. Mwanga ◽  
Arnold S. Mmbando ◽  
Paul C. Mrosso ◽  
Caleb Stica ◽  
Salum A. Mapua ◽  
...  
Keyword(s):  
Low Cost ◽  
Field Trials ◽  
Malaria Vectors ◽  
Bed Nets ◽  
Insecticide Treated Nets ◽  
Indoor Exposure ◽  
Uv Led ◽  
Outdoor Biting ◽  
Malaria Mosquitoes ◽  
User Protection

Abstract Background Eave ribbons treated with spatial repellents effectively prevent human exposure to outdoor-biting and indoor-biting malaria mosquitoes, and could constitute a scalable and low-cost supplement to current interventions, such as insecticide-treated nets (ITNs). This study measured protection afforded by transfluthrin-treated eave ribbons to users (personal and communal protection) and non-users (only communal protection), and whether introducing mosquito traps as additional intervention influenced these benefits. Methods Five experimental huts were constructed inside a 110 m long, screened tunnel, in which 1000 Anopheles arabiensis were released nightly. Eave ribbons treated with 0.25 g/m2 transfluthrin were fitted to 0, 1, 2, 3, 4 or 5 huts, achieving 0, 20, 40, 60, 80 and 100% coverage, respectively. Volunteers sat near each hut and collected mosquitoes attempting to bite them from 6 to 10 p.m. (outdoor-biting), then went indoors to sleep under untreated bed nets, beside which CDC-light traps collected mosquitoes from 10 p.m. to 6 a.m. (indoor-biting). Caged mosquitoes kept inside the huts were monitored for 24 h-mortality. Separately, eave ribbons, UV–LED mosquito traps (Mosclean) or both the ribbons and traps were fitted, each time leaving the central hut unfitted to represent non-user households and assess communal protection. Biting risk was measured concurrently in all huts, before and after introducing interventions. Results Transfluthrin-treated eave ribbons provided 83% and 62% protection indoors and outdoors respectively to users, plus 57% and 48% protection indoors and outdoors to the non-user. Protection for users remained constant, but protection for non-users increased with eave ribbons coverage, peaking once 80% of huts were fitted. Mortality of mosquitoes caged inside huts with eave ribbons was 100%. The UV–LED traps increased indoor exposure to users and non-users, but marginally reduced outdoor-biting. Combining the traps and eave ribbons did not improve user protection relative to eave ribbons alone. Conclusion Transfluthrin-treated eave ribbons protect both users and non-users against malaria mosquitoes indoors and outdoors. The mosquito-killing property of transfluthrin can magnify the communal benefits by limiting unwanted diversion to non-users, but should be validated in field trials against pyrethroid-resistant vectors. Benefits of the UV–LED traps as an intervention alone or alongside eave ribbons were however undetectable in this study. These findings extend the evidence that transfluthrin-treated eave ribbons could complement ITNs.

Otta Seals and Gravseals as Low-Cost Surfacing Alternatives for Low-Volume Roads: Experiences in South Africa

2003 ◽  
Vol 1819 (1) ◽  
pp. 338-342 ◽  
Author(s):  
Simon Oloo ◽  
Rob Lindsay ◽  
Sam Mothilal
Keyword(s):  
South Africa ◽  
Low Cost ◽  
Cost Savings ◽  
Cost Effective ◽  
Field Trials ◽  
Low Volume Roads ◽  
Kwazulu Natal ◽  
Traffic Volumes ◽  
Low Volume ◽  
To Come

The geology of the northeastern part of the province of KwaZulu–Natal, South Africa, is predominantly alluvial with vast deposits of sands. Suitable gravel sources are hard to come by, which results in high graveling and regraveling costs brought about by long haul distances and accelerated gravel loss. Most gravel roads carry fewer than 500 vehicles per day of which less than 10% are heavy vehicles. The high cost of regraveling has led to consideration of upgrading such roads to surfaced standard, even though traffic volumes do not justify upgrading. Traditional chip seals are expensive and cannot be economically justified on roads that carry fewer than 500 vehicles per day. The KwaZulu–Natal Department of Transport is actively involved in efforts to identify cost-effective alternative surfacing products for low-volume roads. Field trials were conducted with Otta seals and Gravseals, which have been used successfully in other countries, as low-cost surfacing products for low-volume roads. The Otta seal is formed by placing graded aggregates on a relatively thick film of soft binder that, because of traffic and rolling, works its way through the aggregates. Gravseal consists of a special semipriming rubberized binder that is covered by a graded aggregate. Both Otta seals and Gravseals provide relatively flexible bituminous surfaces suitable for low-volume roads. Cost savings are derived mainly from the broad aggregate specifications, which allow for the use of marginal materials.

scholarly journals Hobbit: Providing Fall Detection and Prevention for the Elderly in the Real World

2018 ◽  
Vol 2018 ◽  
pp. 1-20 ◽  
Author(s):  
Markus Bajones ◽  
David Fischinger ◽  
Astrid Weiss ◽  
Daniel Wolf ◽  
Markus Vincze ◽  
...  
Keyword(s):  
Real World ◽  
Independent Living ◽  
Low Cost ◽  
Fall Detection ◽  
The Elderly ◽  
Field Trials ◽  
Lessons Learned ◽  
Human Robot Interaction ◽  
Service Robot ◽  
Emergency Situations

We present the robot developed within the Hobbit project, a socially assistive service robot aiming at the challenge of enabling prolonged independent living of elderly people in their own homes. We present the second prototype (Hobbit PT2) in terms of hardware and functionality improvements following first user studies. Our main contribution lies within the description of all components developed within the Hobbit project, leading to autonomous operation of 371 days during field trials in Austria, Greece, and Sweden. In these field trials, we studied how 18 elderly users (aged 75 years and older) lived with the autonomously interacting service robot over multiple weeks. To the best of our knowledge, this is the first time a multifunctional, low-cost service robot equipped with a manipulator was studied and evaluated for several weeks under real-world conditions. We show that Hobbit’s adaptive approach towards the user increasingly eased the interaction between the users and Hobbit. We provide lessons learned regarding the need for adaptive behavior coordination, support during emergency situations, and clear communication of robotic actions and their consequences for fellow researchers who are developing an autonomous, low-cost service robot designed to interact with their users in domestic contexts. Our trials show the necessity to move out into actual user homes, as only there can we encounter issues such as misinterpretation of actions during unscripted human-robot interaction.

scholarly journals Low cost, high performance ultrafiltration membranes from glass fiber-PTFE–graphene composites

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Umar Khan ◽  
Sonia Biccai ◽  
Conor S. Boland ◽  
Jonathan N. Coleman
Keyword(s):  
Flow Rate ◽  
Glass Fibre ◽  
High Performance ◽  
Graphene Nanosheets ◽  
Low Cost ◽  
Composite Membranes ◽  
Field Trials ◽  
Ultrafiltration Membranes ◽  
Alumina Membranes ◽  
Fibre Membrane

AbstractThe development of low-cost ultrafiltration membranes with relatively high flow rate and selectivity is an important goal which could improve access to clean water in the developing world. Here we demonstrate a method to infuse mixtures of graphene nanosheets and Teflon nanoparticles into ultra-cheap glass fibre membranes. Annealing the resultant composites leads to coalescence of the Teflon, resulting in very stable membranes with significantly enhanced mechanical properties. In filtration tests, while adding ~ 10 wt% graphene/Teflon to the glass fibre membrane decreased the flow rate by × 100, the selectivity improved by × 103 compared to the neat glass fibre membrane. This combination of selectively and flow rate was significantly better than any commercial membrane tested under similar circumstances. We found these membranes could remove > 99.99% of 25–250 nm diameter SiC nanoparticles dispersed in ethanol, transmitting only particles with diameters < 40 nm, performance which is superior to commercial alumina membranes. Field trials on dirty canal water showed these composite membranes to remove aluminium to a level × 10 below the EU limit for drinking water and reduce iron and bacteria contents to below detectable levels.

scholarly journals Performance and Profitability of Fungicides for Managing Soybean White Mold: A 10-Year Summary of Cooperative Trials

Plant Disease ◽  
2019 ◽  
Vol 103 (9) ◽  
pp. 2212-2220
Author(s):  
Jhonatan P. Barro ◽  
Maurício C. Meyer ◽  
Claúdia V. Godoy ◽  
Alfredo R. Dias ◽  
Carlos M. Utiamada ◽  
...  
Keyword(s):  
Low Cost ◽  
Disease Incidence ◽  
Network Models ◽  
Field Trials ◽  
White Mold ◽  
Yield Data ◽  
Soybean Price ◽  
Cost Treatment ◽  
Untreated Check ◽  
Yield Responses

White mold, caused by Sclerotinia sclerotiorum, is a yield-limiting disease of soybean in Brazil. Uniform fungicide trials have been conducted annually since 2009. Data from 74 cooperative field trials conducted over a 10-year period were assembled. We selected five fungicides applied two times around flowering: dimoxystrobin plus boscalid (DIMO+BOSC), carbendazim plus procymidone (CARB+PROC), fluazinam (FLUZ), fluopyram (FLUO), and procymidone (PROC). For comparison, thiophanate-methyl (TMET) applied four times was also included as a low-cost treatment. Network models were fitted to the log of white mold incidence (percentages) and log of sclerotia mass data (grams/hectare) and to the nontransformed yield data (kilograms/hectare) for each treatment, including the untreated check. Back-transformation of the meta-analytic estimates indicated that the lowest and highest mean (95% confidence interval [CI]) percent reductions in incidence and sclerotia mass were 54.2 (49.3 to 58.7) and 51.6% (43.7 to 58.3) for TMET and 83.8 (79.1 to 87.5) and 87% (81.9 to 91.6) for CARB+PROC, respectively. The overall mean (95% CI) yield responses ranged from 323 kg/ha (247.4 to 400.3) for TMET to 626 kg/ha (521.7 to 731.7) for DIMO+BOSC, but the variance was significantly reduced by a binary variable (30% threshold) describing disease incidence in the untreated check. On average, an increment of 352 kg/ha was estimated for trials where the incidence was >30% compared with the low-disease scenario. Hence, the probability of breaking even on fungicide costs for the high-disease scenario was >65% for the more effective, but more expensive fungicide (FLUZ) than TMET. For the low-disease scenario, profitability was less likely and depended more on variations in fungicide cost and soybean price.

scholarly journals Rotational moulding in the production of prostheses

1985 ◽  
Vol 9 (1) ◽  
pp. 31-36 ◽  
Author(s):  
A. G. A. Coombs ◽  
R. B. Lawrence ◽  
R. M. Davies
Keyword(s):  
Fatigue Testing ◽  
Low Cost ◽  
Field Trials ◽  
International Standards ◽  
Rotational Moulding ◽  
Simultaneous Application ◽  
Thermoplastic Material ◽  
Early Results ◽  
Bending Loads ◽  
Tapered Column

The most developed of the possible prosthetic options available consists of a hollow tapered column having inserts at each end by which it is clamped through alignment couplings to the socket and foot respectively. For a below-knee application, the complete tapered column prosthesis weighs typically 1 kg. Static and fatigue testing of representative samples by the simultaneous application of compressive and bending loads to the maximum values specified by international standards exposed no failures by the time a million cycles had been reached. This method of fabrication has the merit of being capable of implementation locally on an “as required” basis. Additional advantages include the low cost of the mould tooling and the flexibility to mould a variety of shapes. Prosthetic feet are a possibility as are special shoes and orthotic parts. These may require other materials and experimentation is proceeding using structural and resilient foams. This paper discusses the place of rotational moulding in the provision of prosthetic shanks and shank sections. It covers the selection of thermoplastic material, the moulding conditions and their automation in a machine process, and the development of a suitable range of moulds. Also covered is the question of interfacing between the moulded shank sections and other limb components, fatigue strength as tested to date and early results of patient field trials.

Inter-comparison of environmental low-cost sensors on Arduino platform

2020 ◽  
Vol 63 (1) ◽  
pp. 35-45
Author(s):  
Ariel Fabricio Scagliotti ◽  
Guillermo Antonio Jorge
Keyword(s):  
Relative Humidity ◽  
Ambient Temperature ◽  
Response Times ◽  
Low Cost ◽  
Field Trials ◽  
Reliable Information ◽  
Systematic Comparison

Abstract Low-cost sensors for relative humidity, pressure, and ambient temperature have begun to be used regularly for different applications in which the measurement or control of systems or processes is required using an affordable technology. However, in most cases, reliable information about their performance, capabilities, and limitations is not available. In this work, we aim to establish a systematic comparison between different sensors widely used in conjunction with the Arduino platform, such as the DS18b20, DHT11, BMP180, and BME280 sensors. Laboratory and field trials were performed to determine linearity, accuracy, precision, resolution, response times, and response to loss of power. The results indicate that these devices, despite having a very low cost, can provide relatively reliable information, taking into account their manufacturing characteristics and the specific use required. In turn, this work offers useful information to choose the sensor that best suits a particular project.

Effect of release rate and enantiomeric composition on response to pheromones of Megaplatypus mutatus (Chapuis) in poplar plantations of Argentina and Italy

2013 ◽  
Vol 103 (5) ◽  
pp. 564-569 ◽  
Author(s):  
Hernán Funes ◽  
Eduardo Zerba ◽  
Paola Gonzalez-Audino
Keyword(s):  
Release Rate ◽  
Low Cost ◽  
Field Trials ◽  
Severe Damage ◽  
Baited Traps ◽  
Pheromone Components ◽  
Important Pest ◽  
Poplar Plantations ◽  
Enantiomer Composition ◽  
Megaplatypus Mutatus

AbstractMegaplatypus mutatus (=Platypus sulcatus Chapuis) is an Ambrosia beetle native to South America, which was recently introduced in Italy and its presence there is causing severe damage to the local poplar plantations. The male M. mutatus pheromone is composed of (S)-(+)-6-methyl-5-hepten-2-ol [(+)-sulcatol], 6-methyl-5-hepten-2-one (sulcatone) and 3-pentanol. A series of field trials testing dose, blend and enantiomer composition performed in Argentina and Italy evaluated attraction and found that the optimal release rate of pheromone components as baits in cross vane baited traps (CIPEIN-CV) was 6, 6 and 30 mg day−1 of sulcatone, (+)-sulcatol and 3-pentanol, respectively. It was also determined that racemic sulcatol is as effective as the pure (+)-isomer for the purpose of beetle catch, due to the inert nature of the (−)-isomer allowing the usage of low cost racemic sulcatol instead of highly expensive (+)-sulcatol. The results of our work contribute to the development of pheromone-based local technologies with low environmental impact and low cost for control or monitoring of an important pest.

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