The application of time-series MODIS NDVI profiles for the acquisition of crop information across Afghanistan

We investigated and developed a prototype crop information system integrating 250 m Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI) data with other available remotely sensed imagery, field data, and knowledge as part of a wider project monitoring opium and cereal crops. NDVI profiles exhibited large geographical variations in timing, height, shape, and number of peaks, with characteristics determined by underlying crop mixes, growth cycles, and agricultural practices. MODIS pixels were typically bigger than the field sizes, but profiles were indicators of crop phenology as the growth stages of the main first-cycle crops (opium poppy and cereals) were in phase. Profiles were used to investigate crop rotations, areas of newly exploited agriculture, localized variation in land management, and environmental factors such as water availability and disease. Near-real-time tracking of the current years’ profile provided forecasts of crop growth stages, early warning of drought, and mapping of affected areas. Derived data products and bulletins provided timely crop information to the UK Government and other international stakeholders to assist the development of counter-narcotic policy, plan activity, and measure progress. Results show the potential for transferring these techniques to other agricultural systems

Survey and monitoring of opium poppy and wheat in Afghanistan: 2003-2009

An integrated application of remote-sensing technology was devised and applied in Afghanistan during 2003–2009 providing critical information on cereal and poppy cultivation and poppy eradication. The results influenced UK and international policy and counter-narcotics actions in Afghanistan

Phylogeny and Biogeography of the Carnivorous Plant Family Sarraceniaceae

The carnivorous plant family Sarraceniaceae comprises three genera of wetland-inhabiting pitcher plants: Darlingtonia in the northwestern United States, Sarracenia in eastern North America, and Heliamphora in northern South America. Hypotheses concerning the biogeographic history leading to this unusual disjunct distribution are controversial, in part because genus- and species-level phylogenies have not been clearly resolved. Here, we present a robust, species-rich phylogeny of Sarraceniaceae based on seven mitochondrial, nuclear, and plastid loci, which we use to illuminate this family's phylogenetic and biogeographic history. The family and genera are monophyletic: Darlingtonia is sister to a clade consisting of Heliamphora+Sarracenia. Within Sarracenia, two clades were strongly supported: one consisting of S. purpurea, its subspecies, and S. rosea; the other consisting of nine species endemic to the southeastern United States. Divergence time estimates revealed that stem group Sarraceniaceae likely originated in South America 44–53 million years ago (Mya) (highest posterior density [HPD] estimate = 47 Mya). By 25–44 (HPD = 35) Mya, crown-group Sarraceniaceae appears to have been widespread across North and South America, and Darlingtonia (western North America) had diverged from Heliamphora+Sarracenia (eastern North America+South America). This disjunction and apparent range contraction is consistent with late Eocene cooling and aridification, which may have severed the continuity of Sarraceniaceae across much of North America. Sarracenia and Heliamphora subsequently diverged in the late Oligocene, 14–32 (HPD = 23) Mya, perhaps when direct overland continuity between North and South America became reduced. Initial diversification of South American Heliamphora began at least 8 Mya, but diversification of Sarracenia was more recent (2–7, HPD = 4 Mya); the bulk of southeastern United States Sarracenia originated co-incident with Pleistocene glaciation, <3 Mya. Overall, these results suggest climatic change at different temporal and spatial scales in part shaped the distribution and diversity of this carnivorous plant clade

Towards improving the accuracy of opium yield estimates with remote sensing

Yearly estimates of illicit opium production are key metrics for assessing the effectiveness of the counter-narcotics policy in Afghanistan. Poor security often prevents access to sample locations and puts pressure on field surveyors, resulting in biased sampling and errors in data recording. Supportive methods using aerial digital photography for improving yield estimates were investigated in the UK in 2004, 2005, and 2010. There were good empirical relationships between normalized difference vegetation index and poppy yield indicators (mature capsule volume and dry capsule yield) for individual fields. The results suggested a good generalized relationship across all sampled fields and years (R2 > 0.70) during the 3–4 week period including poppy flowering. Regression estimates using this relationship with the imagery counteracted bias in the sample estimate of yield, reduced sample error, and enabled the production of detailed maps showing the poppy yield distribution. The application of this approach using very-high-resolution satellite imagery was investigated in the context of the annual opium survey in Afghanistan. Initial results indicated the potential for bias correction of yield estimates using a smaller and targeted collection of ground observations as an alternative to random sampling

Down-titration from high-dose combination therapy in asthma: removal of long-acting β₂-agonist

Asthma guidelines recommend reducing inhaled corticosteroids (ICS) to the minimum effective dose, but the timing of long-acting β₂-agonist (LABA) withdrawal is unclear. Recent FDA guidelines recommend LABA withdrawal once asthma is well-controlled. This 13-month double-blind study of patients taking high-dose combination therapy investigated the effect of discontinuation of LABA before ICS down-titration. Adults using salmeterol/fluticasone combination (SFC) 50/500 μg bd were randomized to SFC 50/500 μg bd or fluticasone propionate (FP) 500 μg bd, with subsequent ICS down-titration 8-weekly using a clinical algorithm. The primary outcome was mean daily FP dose, including ICS for exacerbations. 82 subjects were randomized. Asthma was well-controlled at baseline, with mean FEV1 84.8% predicted and Asthma Control Questionnaire (ACQ) score 0.9. There was no significant difference in mean daily FP dose (SFC: 721 μg, FP:816 μg, p = 0.3), but final dose was lower with SFC (534 μg cf. 724 μg, p = 0.005). ICS dose was reduced by ≥80% in 41% SFC and 15% FP patients. Ambulatory lung function was significantly higher with SFC, but there were no differences between groups in rescue β₂-agonist use, clinic spirometry, airway responsiveness, ACQ, sputum eosinophils or FeNO. Baseline airway responsiveness, and pre-reduction blood eosinophils, were significant predictors of mean daily FP dose and dose reduction failure respectively. Many patients prescribed high-dose combination therapy may be over-treated. Substantial reductions in dose can be achieved with a clinical algorithm, reaching lower FP doses with SFC than FP without losing asthma control or increasing disease activity. This study was commenced before mandatory registration of clinical trials