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Graphical abstract Highlights • Y. entomophaga is active against Bt Cry1A-, Cry1C-resistant, Plutella xylostella larvae. • Y. entomophaga is active against indoxacarb/pyrethroid, spinosad-resistant P. xylostella. • LD50 of Y. entomophaga in P. xylostella -challenged larvae (5 days) is 2.7 × 103. Abstract The application of the biocontrol bacterium Yersinia entomophaga as a foliar spray was assessed for its efficacy against larvae of the diamondback moth, Plutella xylostella. The bacterium was applied as either a broth suspension, or as a biopolymer-based gel foliar spray and compared with commercial insecticides Dipel (Bacillus thuringiensis) and Spinosad. The performance of Y. entomophaga was comparable with that of Dipel. The gel-based formulation extended leaf persistence over that of the basic broth culture spray, while also providing higher initial foliar deposition rates. The bacterium was found to multiply within the P. xylostella larvae to 5.8 × 105 cells per larva, while the median lethal dose (LD 50) was determined to be 2.69 × 103 cells per larva. Importantly, B. thuringiensis Cry1A-resistant, Cry1C-resistant, indoxacarb/pyrethroid-resistant, and Spinosad-resistant P. xylostella larvae were susceptible to Y. entomophaga. [ABSTRACT FROM AUTHOR]

Highlights: [•] The pathology of Yersinia entomophaga against Costelytra zealandica was examined. [•] Post ingestion, the larvae exhibited reduced feeding and expulsion of gut contents. [•] Within 48h the bacteria invaded the haemocoel resulting in death by septicaemia. [•] Mortality is directly proportional to dose and time after infection. [•] The LD50 was determined as 2.9×104 bacteria per C. zealandica larva. [ABSTRACT FROM AUTHOR]

III-nitride quantum dots are proving to be promising for application to single photon emitting devices. Research around the globe is revealing several interesting properties of these emitters, including a wide range of emission wavelengths, high temperature operation, and deterministic polarization of the emitted photons. Here a review is given on the single photon emission properties of such III-nitride quantum dots. [ABSTRACT FROM AUTHOR]

We evaluated the rapid changes in regional scalp EEG synchronization in normal subjects with spatial and temporal resolution exceeding prior art 10-fold with a high spatial density array and the Hilbert transform. A curvilinear array of 64 electrodes 3 mm apart extending 18.9 cm across the scalp was used to record EEG at 200/sec. Analytic amplitude (AA) and phase (AP) were calculated at each time step for the 64 traces in the analog pass band of 0.5–120 Hz. AP differences approximated the AP derivative (instantaneous frequency). The AP from unfiltered EEG revealed no reproducible patterns. Filtering was necessary in the β and gamma ranges according to a technique that optimized the correlation of the AP differences with the activity band pass filtered in the alpha range. The sizes of temporal AP differences were usually within ±0.5 radian from the average step corresponding to the center frequency of the pass band. Large AP differences were often synchronized over distances of 6 to 19 cm. An optimal pass band to detect and measure these recurring jumps in AP in the β and γ ranges was found by maximizing the α peak in the cospectrum of the correlation between unfiltered EEG and the band pass AP differences. Synchronized AP jumps recurred in clusters (CAP) at α and theta rates in resting subjects and with EMG. Cortex functions by serial changes in state. The Hilbert transform of EEG from high-density arrays can visualize these state transitions with high temporal and spatial resolution and should be useful in relating EEG to cognition. Hum. Brain Mapping 19:248–272, 2003. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]