High quality InSAR data linked to seasonal change in hydraulic head for an agricultural area in the San Luis Valley, Colorado

In the San Luis Valley (SLV), Colorado legislation passed in 2004 requires that hydraulic head levels in the confined aquifer system stay within the range experienced in the years 1978–2000. While some measurements of hydraulic head exist, greater spatial and temporal sampling would be very valuable in understanding the behavior of the system. Interferometric synthetic aperture radar (InSAR) data provide fine spatial resolution measurements of Earth surface deformation, which can be related to hydraulic head change in the confined aquifer system. However, change in cm-scale crop structure with time leads to signal decorrelation, resulting in low quality data. Here we apply small baseline subset (SBAS) analysis to InSAR data collected from 1992 to 2001. We are able to show high levels of correlation, denoting high quality data, in areas between the center pivot irrigation circles, where the lack of water results in little surface vegetation. At three well locations we see a seasonal variation in the InSAR data that mimics the hydraulic head data. We use measured values of the elastic skeletal storage coefficient to estimate hydraulic head from the InSAR data. In general the magnitude of estimated and measured head agree to within the calculated error. However, the errors are unacceptably large due to both errors in the InSAR data and uncertainty in the measured value of the elastic skeletal storage coefficient. We conclude that InSAR is capturing the seasonal head variation, but that further research is required to obtain accurate hydraulic head estimates from the InSAR deformation measurements

On chemiluminescent emission from an infiltrated chiral sculptured thin film

The theory describing the far-field emission from a dipole source embedded inside a chiral sculptured thin film (CSTF), based on a spectral Green function formalism, was further developed to allow for infiltration of the void regions of the CSTF by a fluid. In doing so, the extended Bruggeman homogenization formalism--which accommodates constituent particles that are small compared to wavelength but not vanishingly small--was used to estimate the relative permittivity parameters of the infiltrated CSTF. For a numerical example, we found that left circularly polarized (LCP) light was preferentially emitted through one face of the CSTF while right circularly polarized (RCP) light was preferentially emitted through the opposite face, at wavelengths within the Bragg regime. The centre wavelength for the preferential emission of LCP/RCP light was red shifted as the refractive index of the infiltrating fluid increased from unity, and this red shift was accentuated when the size of the constituent particles in our homogenization model was increased. Also, the bandwidth of the preferential LCP/RCP emission regime decreased as the refractive index of the infiltrating fluid increased from unity

Crop Updates 2004 - Cereals

This session covers twenty eight papers from different authors: PLENARY 1. Declining profitability in continuous cropping systems. Is more wheat the answer on Duplex soil? Dr Wal Anderson, Department of Agriculture 2. Disease implications of extending the wheat phase in low-medium rainfall areas, Dr Vivian Vanstone and Dr Robert Loughman, Department of Agriculture 3. Prolonged wheat phase on duplex soils – where do weeds set the boundary? Vanessa Stewart, Department of Agriculture WHEAT AGRONOMY 4. Management of small grain screenings in wheat, Dr Wal Anderson and Dr Darshan Sharma, Department of Agriculture 5. Agronomic responses of new wheat varieties, Christine Zaicou-Kunesch, Dr Darshan Sharma, Brenda Shackley, Dr Mohammad Amjad, Dr Wal Anderson and Steve Penny,Department of Agriculture 6. Managing wheat yield reduction from wide rows, Dr Mohammad Amjad and Dr Wal Anderson, Department of Agriculture 7. Row spacing and stubble effect on wheat yield and ryegrass seed set, Glen Riethmuller, Department of Agriculture 8. Grain protein management – lessons learnt on the south coast, Jeremy Lemon, Department of Agriculture 9. Unravelling the mysteries of optimum seed rates, Dr Wal Anderson, Dr Darshan Sharma, Brenda Shackley and Mario D’Antuono, Department of Agriculture 10. Agronomic features for growing better wheat – south east agricultural region 2003, Dr Mohammad Amjad, Veronika Reck and Ben Curtis, Department of Agriculture 11. Agronomic responses of new wheat varieties – great southern agricultural region 2003, Brenda Shackley and Judith Devenish, Department of Agriculture 12. Variety specific responses of new wheat varieties – central agricultural region 2003, Dr Darshan Sharma and Dr Wal Anderson, Department of Agriculture 13. Agronomic responses of new wheat varieties – northern agricultural region 2003, Christine Zaicou-Kunesch, Melaine Kupsch and Anne Smith, Department of Agriculture BARLEY AND OAT AGRONOMY 14. Gairdner for high rainfall – where does Baudin fit in? Blakely Paynter, Roslyn Jettnerand Leanne Schulz, Department of Agriculture 15. Oaten hay – varieties and agronomy, Blakely Paynter, Jocelyn Ball and Tom Sweeny, Department of Agriculture NUTRITION 16. In-furrow fungicide applications in liquid fertiliser, Dr Stephen Loss, CSBP Ltd 17. Elemental sulphur as a fertiliser source in Western Australia, Ashleigh Brooks1A, Justin Fuery2, Geoff Anderson3 and Prof Zed Rengel1,1UWA, 2Summit FertilizerFertilisers and 3Department of Agriculture 18. Genetic variation in potassium efficiency of barley, Paul Damon and Prof. Zed Rengel, Faculty of Natural and Agricultural Sciences, UWA 19. Managing protein through strategic N applications, Eddy Pol and Dr Stephen Loss, CSBP Ltd 20. Nitrogen management for wheat in high rainfall cropping areas, Narelle Hill1, Ray Tugwell1, Dr Wal Anderson1, Ron McTaggart1and Nathan Moyes2, 1Department of Agriculture and 2Landmark 21. Flag smut resistance in current WA wheat varieties, John Majewski and Dr Manisha Shankar, Department of Agriculture 22. Rust resistance update for wheat varieties in WA, Dr Manisha Shankar, John Majewski and Jamie Piotrowski, Department of Agriculture PESTS AND DISEASES 23. Stripe rust in WA – where was it and what can we learn from 2003? Dr Robert Loughman and Ciara Beard, Department of Agriculture 24. Foliar disease management – a key factor in the adoption of Baudin and Hamlin barley, Dr Kithsiri Jayasena, Dr Rob Loughman, Kazue Tanaka and Grey Poulish, Department of Agriculture 25. Validating aphid and virus risk forecasts for cereals, Dr Debbie Thackray, Rohan Prince and Dr Roger Jones, Department of Agriculture and Centre for Legumes in Mediterranean Agriculture HARVESTING 26. Swathing Gairdner barley at 30% moisture, Peter Nelson¹ and Nigel Metz², ¹Cooperative Bulk Handling and ² Fitzgerald Biosphere Group MODELLING 27. Development of a web based grower decision aid application for cereal growers, Dr Leisa Armstrong1, Yee Leong (Alex) Yung1and Dr Moin Salam2 1School of Computer and Information Science, Edith Cowan University; and 2Department of Agriculture 28. Wheat varieties updated in ‘Flowering Calculator’ – a model predicting flowering time, Brenda Shackley, Dr David Tennant, Dr Darshan Sharma and Christine Zaicou‑Kunesch, Department of Agricultur

SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion

Abstract: The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era