28 research outputs found
Small-scale land-use variability affects Anopheles spp. distribution and concomitant Plasmodium infection in humans and mosquito vectors in southeastern Madagascar
Additional file 1. Individual health assessment form
Image plane detection of FRB121102 with the MeerKAT radio telescope
We present the analysis of radio interferometric 2-s images from a MeerKAT
observation of the repeating fast radio burst FRB121102 on September 2019,
during which 11 distinct pulses have been previously detected using high time
and frequency resolution data cubes. In this work, we detected 6 out of the 11
bursts in the image plane at 1.48 GHz with a minimum peak signal-to-noise ratio
(S/N) of 5 {\sigma} and a fluence detection limit of 0.512 Jy ms. These
constitute the first detections of a fast radio burst (FRB) or a radio
transient using 2-s timescale images with MeerKAT data. Analysis of the fitted
burst properties revealed a weighted average precision of 1 arcsec in the
localization of the bursts. The accurate knowledge of FRB positions is
essential for identifying their host galaxy and understanding their mysterious
nature which is still unresolved to this day. We also produced 2-s images at
1.09 GHz but yielded no detection which we attributed to the spectral structure
of the pulses that are mostly higher in strength in the upper frequencies. We
also explore a new approach to difference imaging analysis (DIA) to search for
transients and find that our technique has the potential to reduce the number
of candidates and could be used to automate the detection of FRBs in the image
plane for future MeerKAT observations.Comment: The paper has already been accepted to MNRAS and we wait for proof of
review from the publisher for final publicatio
Field evaluation of synthetic lure (3-methyl-1-butanol) when compared to non odor-baited control in capturing Anopheles mosquitoes in varying land-use sites in Madagascar
Abstract Background Malaria is the 4th largest cause of mortality in Madagascar. To better understand malaria transmission dynamics, it is crucial to map the distribution of the malaria vectors, mosquitoes belonging to the genus Anopheles. To do so, it is important to have a strong Anopheles-specific lure to ensure the maximum number of captures. Previous studies have isolated volatiles from the human skin microbiota and found the compound 3-methyl-1-butanol to be the most attractive to the malaria mosquito, Anopheles gambiae, in a laboratory setting; and recommended 3-methyl-1-butanol as a compound to increase An. gambiae captures in the field. To date, this compound’s ability to lure wild mosquitoes in differing land-use settings has not been tested. In this study, we evaluate the role of the synthetic compound, 3-methyl-1-butanol in combination with field produced CO2 in attracting Anopheles mosquitoes in varying land-use sites in Madagascar. Methods CDC miniature light traps in combination with field produced CO2 were deployed in and around six villages near Ranomafana National Park, Madagascar. To test the role of 3-methyl-1-butanol in luring Anopheles mosquitoes, two traps were set in each land-use site (village, agricultural sites, and forested habitats affiliated with each village). One was baited with the synthetic odor and the other was kept as a non-baited control. Results While 3-methyl-1-butanol baited traps did capture An. gambiae s.l. in this study, we did not find traps baited with synthetic 3-methyl-1-butanol to be more successful in capturing Anopheles mosquitoes, (including Anopheles gambiae s.l.) than the non odor-baited control traps in any of the land-use sites examined; however, regardless of odor bait, trapping near livestock pens resulted in the capture of significantly more Anopheles specimens. Conclusions A strong synthetic lure in combination with insecticide has great potential as a mosquito control. Our findings suggest that trapping mosquitoes near livestock in malaria endemic regions, such as Madagascar, may be more successful at capturing Anopheles mosquitoes than the proposed 3-1-methyl-butanol lure
Achieving sustainable conservation in Madagascar : the case of the newly established Ibity Mountain Protected Area
Globally, the number of protected areas (PAs) has increased exponentially during the last 25 years, particularly in biodiversity-rich developing countries. Many recent initiatives have integrated local-scale socio-economic development into both design and management. Because the rates of deforestation and species extinction are increasing in most parts of the world, substantial efforts have been made to build and strengthen local environmental organizations, to establish new protected areas (NPAs), and to improve natural resource management. An NPA was recently established at Ibity Massif in central Madagascar, where a community-based conservation project is being coordinated by the Missouri Botanical Garden (MBG). In December 2008, a temporary protection order was issued, and definitive establishment of the NPA, which falls under Category V of the IUCN PA system, is expected before the end of 2015. This initiative has involved significant outreach and community education programs to raise awareness of Ibity's conservation and economic importance and the threats to its biodiversity, along with ongoing efforts to reduce fire frequency and implement ecological restoration projects with significant local community participation. In order to ensure the sustainability of this NPA, a co-management plan has been implemented involving MBG, local authorities, and the local population. This study describes the diagnostic process undertaken at Ibity in order to: 1) disseminate the data gathered to inform establishment of the NPA; and 2) summarize the initial state of the environment on the massif prior to the implementation of a management plan, as a baseline for assessing the NPA's effectiveness
