The flowering stage of oilseed rape (Brassica napus L.) is of vital interest in precision agriculture. It has been shown that data describing the flower production of oilseed rape (OSR), at stage 3, ...in spring can be used to predict seed yield at harvest. Traditional field-based techniques for assessing OSR flowers are based on a visual assessment which is subjective and time consuming. However, a high throughput phenotyping technique, using an unmanned aerial vehicle (UAV) with multispectral image (MSI) camera, was used to investigate the growth stages of OSR (in terms of crop height) and to quantify its flower production. A simplified approach using a normalised difference yellowness index (NDYI) was coupled with an iso-cluster classification method to quantify the number of OSR flower pixels and incorporate the data into an OSR seed yield estimation. The estimated OSR seed yield showed strong correlation with the actual OSR seed yield (R.sup.2 = 0.86), as determined using in-situ sensors mounted on the combine harvester. Also, using our approach allowed the variation in crop height to be assessed across all growing stages; the maximum crop height of 1.35 m OSR was observed at the flowering stage. This methodology is proposed for effectively predicting seed yield 3 months prior to harvesting.
A polytriarylamine‐based oligomer is reported as a hole transporting material and its application in solid‐state CH3NH3PbI3 based heterojunction solar cells is described. It yields a power conversion ...efficiency of 12.0% under 99.6 mW cm–2 illumination. In addition to suitable energy levels and high hole mobility, the low preparation cost makes it a promising candidate for photovoltaics.
Stenotrophomonas maltophilia is a nosocomial opportunistic pathogen of the Xanthomonadaceae. The organism has been isolated from both clinical and soil environments in addition to the sputum of ...cystic fibrosis patients and the immunocompromised. Whilst relatively distant phylogenetically, the closest sequenced relatives of S. maltophilia are the plant pathogenic xanthomonads.
The genome of the bacteremia-associated isolate S. maltophilia K279a is 4,851,126 bp and of high G+C content. The sequence reveals an organism with a remarkable capacity for drug and heavy metal resistance. In addition to a number of genes conferring resistance to antimicrobial drugs of different classes via alternative mechanisms, nine resistance-nodulation-division (RND)-type putative antimicrobial efflux systems are present. Functional genomic analysis confirms a role in drug resistance for several of the novel RND efflux pumps. S. maltophilia possesses potentially mobile regions of DNA and encodes a number of pili and fimbriae likely to be involved in adhesion and biofilm formation that may also contribute to increased antimicrobial drug resistance.
The panoply of antimicrobial drug resistance genes and mobile genetic elements found suggests that the organism can act as a reservoir of antimicrobial drug resistance determinants in a clinical environment, which is an issue of considerable concern.
A novel multi-technique approach has been applied for the identification and mapping of wild orchids using a combination of remote sensing and spectral image analysis. The five orchid species ...identified were the common spotted-orchid (
Dactylorhiza fuchsia
), heath spotted-orchid (
Dactylorhiza maculata
)
,
pyramidal orchid (
Anacamptis pyramidalis
), heath fragrant-orchid (
Gymnadenia borealis
), and the dark-red helleborine (
Epipactis atrorubens
). Field studies have been done using a hand-held spectrometer operating in the 400–700 nm visible spectrum, photogrammetry using a digital camera as well as a multispectral image camera operating at the specific spectral bands of 450 nm (blue), 560 nm (green), 650 nm (red), 730 nm (red edge) and 840 nm (near-infrared) attached to an unmanned aerial vehicle Data analysis, using the hand-held spectrometer, followed by pattern recognition using principal component analysis and partial least squares-discriminant analysis, have identified the key distinguishing wavelengths for identification of the 5 orchid types as 400, 410, 420 and 560 nm. The use of remote sensing, using the UAV-MSI, and application of a dedicated spectral index has enabled field identification of the orchids. Finally, object-based image analysis of field gathered photogrammetry imagery, has enabled use of shape, size, and color to identify and distinguish orchid species. The developed data analytic tool, using random forest classification, can be used to identify and characterize wild orchids across multiple sites within their short lifespan with an accuracy of 86%. Any longer-term study would provide invaluable information on the diversity and complexity of orchid habitat, population variation both intra- and inter-site location, as well as the impact of climate change.
As one of the world's major crops, oats (
Avena sativa
L.) require management strategies to increase their yield and quality. This study utilised an unmanned aerial vehicle (UAV) with multispectral ...image sensors to predict winter oats height (1.18 m at ripening stage) and yield (maximum >7.62 t per ha) using the normalised difference vegetation index (NDVI) and chlorophyll green vegetation index (CI green VI) across three different growth stages (flowering, grain filling and ripening). To corroborate the vegetation indices ground truth data on the measured crop yield, a variety of chemical soil health indicators (
i.e.
nitrogen, phosphorus, potassium, pH, and soil organic matter), and a crop quality indicator (β-glucan) were determined. A hierarchical multinomial logistic regression machine learning model was developed to predict the oats yield incorporating the chemical soil health indicators and crop quality indicator. The determined 'combination model' using the CI green VI, with 16 soil feature parameters, showed good specificity (0.87), sensitivity (0.95), and accuracy (0.93) at estimating the very high oat yield. Finally, the study provides the range of soil nutrient levels and the crop quality indicator that farmers must maintain to gain the highest oat yield at harvest. The findings of this research study will be particularly valuable as a Precision Agriculture management strategy for maximising winter oat yield and quality.
As one of the world's major crops, oats (
Avena sativa
L.) require management strategies to increase their yield and quality.
High mobility organic semiconductor formulations with excellent uniformity across large area substrates are prepared via the use of formulations containing small molecule and high permittivity ...semiconducting oligomers. The use of these high‐k (k > 3.3) oligomers allows control of the wetting via the manipulation of the surface energy of the substrate being coated. Organic thin film transistors results with mobilities of up to 5 cm2 V‐1 s‐1, standard deviation <10 %, on/off ratios of 109 are presented.
High mobility organic semiconductor formulations with excellent uniformity are prepared by combining a small molecule and high permittivity semiconducting oligomers. The use of these high‐k (k > 3.3) oligomers allows control of the performance by manipulation of the surface energy of the substrate. Organic thin film transistors results with mobilities of 5 cm2 V‐1 s‐1, standard deviation <10% and on/off ratios of 109 are presented.
The torsional motions of jet-cooled 1,4-bis(phenylethynyl)benzene (BPEB), a prototype molecular wire, were studied using cavity ring-down spectroscopy in the first UV absorption band (316−321 nm). ...The torsional spectrum of 1,4-bis(phenylethynyl)-2,3,5,6-tetradeuteriobenzene was also recorded in the gas phase. Both spectra were successfully simulated using simple cosine potentials to describe the torsional motions. The ground-state barrier to rotation was estimated to be 220−235 cm-1, which is similar to that of diphenylacetylene (tolane). Complementary DFT calculations were found to overestimate the torsional barrier.
In this paper, we describe a versatile method for the patterning of dielectric and organic semiconductor (OSC) in an organic thin‐film transistor (OTFT) that we have developed using commercially ...available material sets. OTFTs with on/off ratios of 109 and mobilities > 4 cm2/Vs can be produced using CPI's FlexOSTM OSC and Orthogonal Inc. OSCoR1510 photoresist.
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