Effectiveness of Pyriproxyfen and Olyset Duo in Controlling Insecticide Resistant Mosquito Populations in Burkina Faso

The escalation of Long-Lasting Insecticidal Nets (LLINs) mass distribution marked the beginning of a period of malaria decline in sub-Saharan Africa. However, the emergence and spread of insecticide resistance in malaria mosquitoes is a threat to the effectiveness and sustainability of this vector control method. In this context, it is necessary to design and evaluate new compounds and methods that attenuate or even reverse the insecticide resistance trend. Olyset Duo is a novel LLIN that combines the insecticide properties of permethrin and the chemosterilising effect of pyriproxyfen (PPF). The rationale is that resistant mosquitoes that survive the contact with the net would not be able to transfer the resistance genes to the offspring, eventually influencing the resistant phenotype of the mosquito population. In the first part of this study the sterilising and sub-lethal effect of PPF and Olyset Duo was evaluated by a range of bioassays with laboratory and wild mosquito populations. PPF significantly affected the longevity, oogenesis, oviposition and hatching rate of susceptible and resistant mosquitoes, although the effect was partially diminished on the resistant colonies. The possible reasons and implications of PPF performance under controlled conditions are discussed. The second part of this thesis was done within the context of an Olyset Duo Randomised Controlled Trial (RCT) set in Banfora District, Burkina Faso. The RCT had a stepped-wedge design which ensured that Olyset Duo nets gradually replaced Olyset nets in randomly allocated cluster of villages until the Olyset Duo coverage was total. Wild mosquitoes collected in sentinel sites with Olyset Duo showed evident signs of reproductive impairment even after 1 year of deployment. Insecticide resistance strength was monitored during the RCT in several sentinel sites, and time-response data showed an overall reduction of permethrin resistance strength after the distribution of Olyset Duo. This is the most detailed study on the effect of Olyset Duo on key entomological factors of wild mosquito populations. The standardised protocols as well as the dataset obtained are valuable information for ongoing evaluation of Olyset Duo and PPF as a tool for controlling malaria mosquitoes and as a potential alternative for insecticide resistance management

Fractura Múltiple de Cadera en Canino Mestizo: Descripción de Caso Clínico.

Se presenta un caso en la Clínica Veterinaria de Pequeños Animales de la Universidad de laAmazonia de un paciente canino hembra con fractura múltiple de la cadera. Este tipo de fracturas pueden afectar órganos blandos como vejiga, recto y útero además de comprometer la movilidad del animal; las ayudas diagnosticas como el estudio radiográfico, ecográfico y hematológico ofrecen información médica indispensable para llegar a los diagnósticos. En Florencia, Caquetá no se cuenta con la infraestructura, equipos ni profesionales especializados para realizar las correcciones ortopédicas para estos casos, por eso se manejan terapias alternas fácilmente costeadas por los propietarios con las cuales se ha observado buenos resultados

FTIR-ATR Spectroscopy Combined with Multivariate Regression Modeling as a Preliminary Approach for Carotenoids Determination in Cucurbita spp

Quantitative analysis of carotenoids has been extensively reported using UV\u2010Vis spectrophotometry and chromatography, instrumental techniques that require complex extraction protocols with organic solvents. Fourier transform infrared spectroscopy (FTIR) is a potential alternative for simplifying the analysis of food constituents. In this work, the application of FTIR with attenuated total reflectance (ATR) was evaluated for the determination of total carotenoid content (TCC) in Cucurbita spp. samples. Sixty\u2010three samples, belonging to different cultivars of butternut squash (C. moschata) and pumpkin (C. maxima), were selected and analyzed with FTIR\u2010 ATR (attenuated total reflectance). Three different preparation protocols for samples were followed: homogenization (A), freeze\u2010drying (B), and solvent extraction (C). The recorded spectra were used to develop regression models by Partial Least Squares (PLS), using data from TCC, determined by UV\u2010Vis spectrophotometry. The PLS regression model obtained with the FTIR data from the freeze\u2010dried samples, using the spectral range 920\u20133000 cm 121, had the best figures of merit (R2CAL of 0.95, R2PRED of 0.93 and RPD of 3.78), being reliable for future application in agriculture. This approach for carotenoid determination in pumpkin and squash avoids the use of organic solvents. Moreover, these results are a rationale for further exploring this technique for the assessment of specific carotenoids in food matrices

Efficacy of Olyset Duo, a bednet containing pyriproxyfen and permethrin, versus a permethrin-only net against clinical malaria in an area with highly pyrethroid-resistant vectors in rural Burkina Faso: a cluster-randomised controlled trial

Background Substantial reductions in malaria incidence in sub-Saharan Africa have been achieved with massive deployment of long-lasting insecticidal nets (LLINs), but pyrethroid resistance threatens control. Burkina Faso is an area with intense malaria transmission and highly pyrethroid-resistant vectors. We assessed the effectiveness of bednets containing permethrin, a pyrethroid, and pyriproxyfen, an insect growth regulator, versus permethrin-only (standard) LLINs against clinical malaria in children younger than 5 years in Banfora, Burkina Faso. Methods In this two-group, step-wedge, cluster-randomised, controlled, superiority trial, standard LLINs were incrementally replaced with LLINs treated with permethrin plus pyriproxyfen (PPF) in 40 rural clusters in Burkina Faso. In each cluster, 50 children (aged 6 months to 5 years) were followed up by passive case detection for clinical malaria. Cross-sectional surveys were done at the start and the end of the transmission seasons in 2014 and 2015. We did monthly collections from indoor light traps to estimate vector densities. Primary endpoints were the incidence of clinical malaria, measured by passive case detection, and the entomological inoculation rate. Analyses were adjusted for clustering and for month and health centre. This trial is registered as ISRCTN21853394. Findings 1980 children were enrolled in the cohort in 2014 and 2157 in 2015. At the end of the study, more than 99% of children slept under a bednet. The incidence of clinical malaria was 2·0 episodes per child-year in the standard LLIN group and 1·5 episodes per child-year in the PPF-treated LLIN group (incidence rate ratio 0·88 [95% CI 0·77–0·99; p=0·04]). The entomological inoculation rate was 85 (95% CI 63–108) infective bites per transmission season in the standard LLIN group versus 42 (32–52) infective bites per transmission season in the PPF-treated LLIN group (rate ratio 0·49, 95% CI 0·32–0·66; p<0·0001). Interpretation PPF-treated LLINs provide greater protection against clinical malaria than do standard LLINs and could be used as an alternative to standard LLINs in areas with intense transmission of Plasmodium falciparum malaria and highly pyrethroid-resistant vectors. Funding EU Seventh Framework Programme

Impacto de la apertura económica en el cultivo de palma africana en Colombia

Tesis (Economista)-- Corporación Universitaria Autónoma de Occidente, 1993PregradoEconomist

Análisis de estados financieros, presupuestos y leasing: Evaluación de casos para la administración financiera

Trabajo de grado (Ingeniero Industrial)-- Universidad Autónoma de Occidente, 1996PregradoIngeniero(a) Industria