Impact des filets imprégnés de deltaméthrine sur les populations de glossines au Parc zoologique d'Abidjan et à l'Université Nangui Abrogoua.

Des enquêtes entomologiques antérieures réalisées à Abidjan dans le Parc National du Banco et les reliques forestières du Parc zoologique (Zoo) d'Abidjan et de l'Université Nangui Abrogoua (UNA), ont montré la présence de Glossina palpalis palpalis, vecteur majeur des trypanosomoses humaine et animale en Côte d'Ivoire. Face au risque encouru par les populations humaines et animales de cette ville, une lute antivectorielle basée sur une nouvelle technique, les filets imprégnés de deltaméthrine a été mise en place au Zoo. L'Université Nangui Abrogoua a servi de site témoin. L'objectif a été d'évaluer l'impact de ces filets dans le cadre d'une lutte antivectorielle au Zoo d'Abidjan. Avant la pose des filets en février 2011, des captures de glossines ont été effectuées de novembre 2010 à janvier 2011 avec 12 pièges "Vavoua" posés Durant quatre jours consécutifs sur les différents sites. Les évaluations ont débuté après la crise post-électorale, en septembre 2011. Le site témoin a été perturbé par les travaux de réaménagement, qui ont détruit une partie de l'habitat des glossines. Au Zoo, la DAP a chuté brusquement de 1,8 à 0 glossine/ piège/jour. A l'Université, la densité a baissé progressivement, de 0,4 à 0,2 glossine/ piège/ jour, avant de s'annuler. L'utilisation des filets imprégnés de deltaméthrine a été très efficace, cet outil pourrait constituer une option supplémentaire dans la lutte contre les trypanosomoses.Mots clés: lutte anti-vectorielle, Filets, Parc zoologique, l'Université Nangui Abrogoua. Impact of nets impregnated with deltamethrin on tsetse populations in Abidjan Zoological Park and the Nangui Abrogouab University. Using nets impregnated with deltamethrin against tsetsePrevious entomological surveys carried out in Abidjan in the Banco National Park and forest relics of Abidjan zoological Park and the Nangui Abrogoua University showed the presence of Glossina palpalis palpalis, main vector of human and animal trypanosomiasis in Ivory Coast. Cope with the risk to human and animal populations of this city, vector control based on a new technique that is nets impregnated with deltamethrin have been set up at the Zoo. The University Nangui Abrogoua served as a control site. The objective was to evaluate the impact of deltamethrin impregnated nets in vector control of Abidjan Zoo. Before the introduction of insecticide-treated nets in February 2011, the flies catches were conducted from November 2010 to January 2011 with 12 "Vavoua" traps laid during four consecutive days in different sites. Assessments began after the post-election crisis in September 2011. The control site was disrupted by the redevelopment, which destroyed part of the tsetse habitat. At The Zoo, the DAP fell sharply from 1.8 to 0 of tsetse / trap / day. The DAP has dropped sharply from 1.8 to 0 of tsetse / trap / day. At the University, the density decreased gradually from 0.4 to 0.2 tsetse / trap / day, before cancel. The use of nets treated with deltamethrin has been very effective, this tool could be an additional option in the fight against trypanosomiasis.Keywords: nets, zoological park, Nangui Abrogoua University, vector control

Assessment of the Efficiency of Insecticide Paint and Impregnated Nets on Tsetse Populations: Preliminary Study in Forest Relics of Abidjan, Côte d’Ivoire

Glossina palpalis palpalis is the main vector of human and animal trypanosomiasis in Côte d’Ivoire. This species, being the only tsetse species in the city of Abidjan, is hosted by the National park of Banco located in the middle of Abidjan, the zoological park and in a relic forest within the University of Nangui-Abrogoua, both in Abidjan. A programme for the elimination of these suburban tsetse populations has been initiated, in the context of which various tsetse control tools have been evaluated. In the zoological park, insecticidal paint (Inesfly®) was applied around the animal cages, and then supplemented with insecticide-impregnated netting around the larger animal cages. Tsetse population densities were monitored with Vavoua-style traps both inside the zoological park and in the site of University Nangui Abrogoua used as control site. Tsetse densities in the traps fell by over 90% following application of the insecticidal paint, and declined to zero after adding the insecticide impregnated nets in both study sites. The study confirms the close contact between tsetse populations from the zoological park and the University Nangui Abrogoua area, and shows that the sequential use of insecticide paint and impregnated nets can be effective for tsetse control

Modeling approaches for assessing device-based measures of energy expenditure in school-based studies of body weight status

BackgroundObesity has become an important threat to children’s health, with physical and psychological impacts that extend into adulthood. Limited physical activity and sedentary behavior are associated with increased obesity risk. Because children spend approximately 6 h each day in school, researchers increasingly study how obesity is influenced by school-day physical activity and energy expenditure (EE) patterns among school-aged children by using wearable devices that collect data at frequent intervals and generate complex, high-dimensional data. Although clinicians typically define obesity in children as having an age-and sex-adjusted body mass index (BMI) value in the high percentiles, the relationships between school-based physical activity interventions and BMI are analyzed using traditional linear regression models, which are designed to assess the effects of interventions among children with average BMI, limiting insight regarding the effects of interventions among children categorized as overweight or obese.MethodsWe investigate the association between wearable device–based EE measures and age-and sex-adjusted BMI values in data from a cluster-randomized, school-based study. We express and analyze EE levels as both a scalar-valued variable and as a continuous, high-dimensional, functional predictor variable. We investigate the relationship between school-day EE (SDEE) and BMI using four models: a linear mixed-effects model (LMEM), a quantile mixed-effects model (QMEM), a functional mixed-effects model (FMEM), and a functional quantile mixed-effects model (FQMEM). The LMEM and QMEM include SDEE as a summary measure, whereas the FMEM and FQMEM allow for the modeling of SDEE as a high-dimensional covariate. The FMEM and FQMEM allow the influence of the time of day at which physical activity is performed to be assessed, which is not possible using the LMEM or the QMEM. The FMEM assesses how frequently collected SDEE data influences mean BMI, whereas the FQMEM assesses the effects on quantile levels of BMI.ResultsThe LMEM and QMEM detected a statistically significant effect of overall mean SDEE on log (BMI) (the natural logarithm of BMI) after adjusting for intervention, age, race, and sex. The FMEM and FQMEM provided evidence for statistically significant associations between SDEE and log (BMI) for only a short time interval. Being a boy or being assigned a stand-biased desk is associated with a lower log (BMI) than being a girl or being assigned a traditional desk. Across our models, age was not a statistically significant covariate, and white students had significantly lower log (BMI) than non-white students in quantile models, but this significant effect was observed for only the 10th and 50th quantile levels of BMI. The functional regression models allow for additional interpretations of the influence of EE patterns on age-and sex-adjusted BMI, whereas the quantile regression models enable the influence of EE patterns to be assessed across the entire BMI distribution.ConclusionThe FQMEM is recommended when interest lies in assessing how device-monitored SDEE patterns affect children of all body types, as this model is robust and able to assess intervention effects across the full BMI distribution. However, the sample size must be sufficiently large to adequately power determinations of covariate effects across the entire BMI distribution, including the tails

Fine scale spatial investigation of multiple insecticide resistance and underlying target-site and metabolic mechanisms in Anopheles gambiae in central Côte d’Ivoire

Routine monitoring of occurrence, levels and mechanisms of insecticide resistance informs effective management strategies, and should be used to assess the effect of new tools on resistance. As part of a cluster randomised controlled trial evaluating a novel insecticide-based intervention in central Côte d’Ivoire, we assessed resistance and its underlying mechanisms in Anopheles gambiae populations from a subset of trial villages. Resistance to multiple insecticides in An. gambiae s.s. and An. coluzzii was detected across villages, with dose–response assays demonstrating extremely high resistance intensity to the pyrethroid deltamethrin (> 1,500-fold), and mortality following exposure to pyrethroid-treated bednets was low (< 30% mortality in cone bioassays). The 1014F kdr mutation was almost fixed (≥ 90%) in all villages but the 1575Y kdr-amplifying mutation was relatively rare (< 15%). The carbamate and organophosphate resistance-associated Ace-1 G119S mutation was also detected at moderate frequencies (22–43%). Transcriptome analysis identified overexpression of P450 genes known to confer pyrethroid resistance (Cyp9K1, Cyp6P3, and Cyp6M2), and also a carboxylesterase (COEAE1F) as major candidates. Cyp6P3 expression was high but variable (up to 33-fold) and correlated positively with deltamethrin resistance intensity across villages (r2 = 0.78, P = 0.02). Tools and strategies to mitigate the extreme and multiple resistance provided by these mechanisms are required in this area to avoid future control failures

Semi-field evaluation of the cumulative effects of a "lethal House Lure" on malaria mosquito mortality

Background: There is growing interest in the potential to modify houses to target mosquitoes with insecticides or repellents as they search for human hosts. One version of this 'Lethal House Lure' approach is the In2Care® EaveTube, which consists of a section of polyvinyl chloride (PVC) pipe fitted into a closed eave, with an insert comprising electrostatic netting treated with insecticide powder placed inside the tube. Preliminary evidence suggests that when combined with screening of doors and windows, there is a reduction in entry of mosquitoes and an increase in mortality. However, the rate of overnight mortality remains unclear. The current study used a field enclosure built around experimental huts to investigate the mortality of cohorts of mosquitoes over multiple nights. Methods: Anopheles gambiae sensu lato mosquitoes were collected from the field as larvae and reared through to adult. Three-to-five days old adult females were released inside an enclosure housing two modified West African style experimental huts at a field site in M'be, Côte d'Ivoire. Huts were either equipped with insecticide-treated tubes at eave height and had closed windows (treatment) or had open windows and open tubes (controls). The number of host-seeking mosquitoes entering the huts and cumulative mortality were monitored over 2 or 4 days. Results: Very few (0-0.4%) mosquitoes were able to enter huts fitted with insecticide-treated tubes and closed windows. In contrast, mosquitoes continually entered the control huts, with a cumulative mean of 50-80% over 2 to 4 days. Baseline mortality with control huts was approximately 2-4% per day, but the addition of insecticide-treated tubes increased mortality to around 25% per day. Overall cumulative mortality was estimated to be up to 87% over 4 days when huts were fitted with tubes. Conclusion: Only 20-25% of mosquitoes contacted insecticide-treated tubes or entered control huts in a given night. However, mosquitoes continue to host search over sequential nights, and this can lead to high cumulative mortality over 2 to 4 days. This mortality should contribute to community-level reduction in transmission assuming sufficient coverage of the intervention

Application of response surface method to carbamazepine removal in photo-ozonation reaction under alkaline condition

In this study, the photo-ozonation reaction for carbamazepine (CBZ) removal was investigated under alkaline conditions. Response surface methodology based on a central composite design was used to obtain the optimum experimental conditions, and examine both main and interaction effects of the photo-ozonation reaction variables such as O-3 concentration, H2O2 concentration and UV intensity. The level of O-3 concentration significantly influenced CBZ removal (p &lt; 0.001). CBZ removal increased with increasing both O-3 and H2O2 concentration up to a certain level, whereas further increase in O-3 and H2O2 concentration resulted in an adverse effect due to the hydroxyl radical scavenging effect. The optimum conditions for complete CBZ removal at pH 9 were found to be 0.89 mg of O-3 l(-1), 4.85 mg of H2O2 l(-1) and 3.18 mW of UV intensity cm(-2), respectively.N

Application of response surface method to carbamazepine removal in photo-ozonation reaction under alkaline condition

In this study, the photo-ozonation reaction for carbamazepine (CBZ) removal was investigated under alkaline conditions. Response surface methodology based on a central composite design was used to obtain the optimum experimental conditions, and examine both main and interaction effects of the photo-ozonation reaction variables such as O-3 concentration, H2O2 concentration and UV intensity. The level of O-3 concentration significantly influenced CBZ removal (p < 0.001). CBZ removal increased with increasing both O-3 and H2O2 concentration up to a certain level, whereas further increase in O-3 and H2O2 concentration resulted in an adverse effect due to the hydroxyl radical scavenging effect. The optimum conditions for complete CBZ removal at pH 9 were found to be 0.89 mg of O-3 l(-1), 4.85 mg of H2O2 l(-1) and 3.18 mW of UV intensity cm(-2), respectively.This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology (MEST) (No.2012-0005114).OAIID:oai:osos.snu.ac.kr:snu2013-01/102/0000005866/1SEQ:1PERF_CD:SNU2013-01EVAL_ITEM_CD:102USER_ID:0000005866ADJUST_YN:YEMP_ID:A072570DEPT_CD:903CITE_RATE:1.122FILENAME:첨부된 내역이 없습니다.DEPT_NM:환경보건학과EMAIL:[email protected]_YN:NCONFIRM:

Generalized functional linear regression models with a mixture of complex function-valued and scalar-valued covariates prone to measurement error

While extensive work has been done to correct for biases due to measurement error in scalar-valued covariates prone to errors in generalized linear regression models, limited work has been done to address biases associated with functional covariates prone to errors or the combination of scalar and functional covariates prone to errors in these models. We propose Simulation Extrapolation (SIMEX) and Regression Calibration approaches to correct measurement errors associated with a mixture of functional and scalar covariates prone to classical measurement errors in generalized functional linear regression. The simulation extrapolation method is developed to handle the functional and scalar covariates prone to errors. We also develop methods based on regression calibration extended to our current measurement error settings. Extensive simulation studies are conducted to assess the finite sample performance of our developed methods. The methods are applied to the 2011-2014 cycles of the National Health and Examination Survey data to assess the relationship between physical activity and total caloric intake with type 2 diabetes among community-dwelling adults living in the United States. We treat the device-based measures of physical activity as error-prone functional covariates prone to complex arbitrary heteroscedastic errors, while the total caloric intake is considered a scalar-valued covariate prone to error. We also examine the characteristics of observed measurement errors in device-based physical activity by important demographic subgroups including age, sex, and race

Comparison of two measurement error correction approaches to assess the association between choline intake and incident of coronary heart disease after adjusting for quartile levels of device-based measures of physical activity among U.S. community dwelling adults

Background. The association between choline and heart disease is unclear. While some studies indicate statistically significant associations, others don’t. This study compared two measurement error correction approaches to assess the relationship between dietary choline and incident of coronary heart disease among U.S. community dwelling adults. Methods. We first conducted simulations to compare the performance of 5 estimation approaches: benchmark analysis, 1-Day method, average method, linear mixed effects approach to measurement error correction (LME_ME), and simulation extrapolation (SIMEX) under different simulation settings including varying sample sizes (n = 200, 500, 1000) and magnitudes of measurement errors (standard deviation of true exposure σ_X = 1, 1.5, 2, 3; standard deviation of random measurement error σ_U= 0.5, 1, 2). Using data from the 2011-2012 and the 2013-2014 cycles of NHANES, we examined the association between dietary choline intake and the incidence of coronary heart disease (CHD) while adjusting for device-based measures of physical activity, age, gender, race, education, BMI, and smoking. The residual method was used to adjust for total energy intake and 1-Day method, average method, LME_ME, and SIMEX were performed to obtain the odds ratio for CHD events by energy-adjusted choline intake in NHANES data. Results. Our simulation studies indicated that the estimation biases increased with increasing values of the standard deviation of the measurement error when the standard deviation of true exposure was held constant. LME_ME corrects most of the bias due to measurement error, except when standard deviation of true exposure is small and with small sample sizes. The SIMEX method performed better in correcting measurement error as the standard deviation of the true exposure increased. Analysis of NHANES data found that choline intake was significantly and inversely associated with CHD incidence in 1-Day method (β = -0.001 (95% CI: -0.003, -0.0002), OR = 0.999). However, the association was not statistically significant after correcting for measurement error using the average method, LME_ME, and SIMEX. Conclusions. Based on our simulation studies, we observed that the LME_ME performs better with smaller magnitudes of measurement errors (σ_X&lt;1, or when both σ_X and σ_U range between 1 and 2) while SIMEX performed better when the magnitude of measurement error is suspected to be large (σ_X&gt;2). Choline intake was not statistically significantly associated with CHD incidence after correcting for bias due to measurement error