ORCID Profile
0000-0001-8270-4578
Current Organisation
Leiden University Medical Center, the Netherlands
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Publisher: Springer Science and Business Media LLC
Date: 27-03-2018
DOI: 10.1038/S41598-018-22712-Z
Abstract: Mosquito control with bednets, residual sprays or fumigation remains the most effective tool for preventing vector-borne diseases such as malaria, dengue and Zika, though there are no widely used entomological methods for directly assessing its efficacy. Mosquito age is the most informative metric for evaluating interventions that kill adult mosquitoes but there is no simple or reliable way of measuring it in the field. Near-Infrared Spectroscopy (NIRS) has been shown to be a promising, high-throughput method that can estimate the age of mosquitoes. Currently the ability of NIRS to measure mosquito age is biased, and has relatively high in idual mosquito measurement error, though its capacity to rigorously monitor mosquito populations in the field has never been assessed. In this study, we use machine learning methods from the chemometric literature to generate more accurate, unbiased estimates of in idual mosquito age. These unbiased estimates produce precise population-level measurements, which are relatively insensitive to further increases in NIRS accuracy when feasible numbers of mosquitoes are s led. The utility of NIRS to directly measure the impact of pyrethroid resistance on mosquito control is illustrated, showing how the technology has potential as a highly valuable tool for directly assessing the efficacy of mosquito control interventions.
Publisher: JMIR Publications Inc.
Date: 29-08-2017
DOI: 10.2196/MENTAL.5453
Abstract: There is a need for brief screening methods for psychiatric disorders in clinical practice. This study assesses the validity and accuracy of a brief self-report screening questionnaire, the Web Screening Questionnaire (WSQ), in detecting psychiatric disorders in a study group comprising the general population and psychiatric outpatients aged 18 years and older. The aim of this study was to investigate whether the WSQ is an adequate test to screen for the presence of depressive and anxiety disorders in clinical practice. Participants were 1292 adults (1117 subjects from the general population and 175 psychiatric outpatients), aged 18 to 65 years. The discriminant characteristics of the WSQ were examined in relation to the (“gold standard”) Mini-International Neuropsychiatric Interview-Plus (MINI-Plus) disorders, by means of sensitivity, specificity, area under the curve (AUC), and positive and negative predictive values (PPVs, NPVs). The specificity of the WSQ to in idually detect depressive disorders, anxiety disorders, and alcohol abuse or dependence ranged from 0.89 to 0.97 for most disorders, with the exception of post-traumatic stress disorder (0.52) and specific phobia (0.73). The sensitivity values ranged from 0.67 to 1.00, with the exception of depressive disorder (0.56) and alcohol abuse or dependence (0.56). Given the low prevalence of separate disorders in the general population s le, NPVs were extremely high across disorders (≥0.97), whereas PPVs were of poor strength (range 0.02-0.33). In this study group, the WSQ was a relatively good screening tool to identify in iduals without a depressive or anxiety disorder, as it accurately identified those unlikely to suffer from these disorders (except for post-traumatic stress disorders and specific phobias). However, in case of a positive WSQ screening result, further diagnostic procedures are required.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 04-05-2018
Abstract: We report the first use of near-infrared spectroscopy for rapid, low-cost, noninvasive detection of Zika virus in Aedes aegypti .
Publisher: Springer Science and Business Media LLC
Date: 25-06-2018
DOI: 10.1038/S41598-018-27998-7
Abstract: To date, no methodology has been described for predicting the age of Aedes albopictus Skuse mosquitoes, commonly known as Asian tiger mosquitoes. In this study, we report the potential of near-infrared spectroscopy (NIRS) technique for characterizing the age of female laboratory reared Ae . albopictus . Using leave-one-out cross-validation analysis on a training set, laboratory reared mosquitoes preserved in RNA later for up to a month were assessed at 1, 3, 7, 9, 13, 16, 20 and 25 days post emergence. Mosquitoes (N = 322) were differentiated into two age classes ( or ≥ 7 days) with 93% accuracy, into three age classes ( , 7–13 and days old) with 76% accuracy, and on a continuous age scale to within ±3 days of their actual average age. Similarly, models predicted mosquitoes (N = 146) excluded from the training model with 94% and 71% accuracy to the two and the three age groups, respectively. We show for the first time that NIRS, with an improved spectrometer and fibre configuration, can be used to predict the age of laboratory reared female Ae . albopictus . Characterization of the age of Ae . albopictus populations is crucial for determining the efficacy of vector control interventions that target their survival.
Location: Netherlands
Location: Netherlands
Location: United States of America
Location: United States of America
No related grants have been discovered for Floyd Dowell.