Herbivory by a Phloem-Feeding Insect Inhibits Floral Volatile Production

There is extensive knowledge on the effects of insect herbivory on volatile emission from vegetative tissue, but little is known about its impact on floral volatiles. We show that herbivory by phloem-feeding aphids inhibits floral volatile emission in white mustard Sinapis alba measured by gas chromatographic analysis of headspace volatiles. The effect of the Brassica specialist aphid Lipaphis erysimi was stronger than the generalist aphid Myzus persicae and feeding by chewing larvae of the moth Plutella xylostella caused no reduction in floral volatile emission. Field observations showed no effect of L. erysimi-mediated floral volatile emission on the total number of flower visits by pollinators. Olfactory bioassays suggested that although two aphid natural enemies could detect aphid inhibition of floral volatiles, their olfactory orientation to infested plants was not disrupted. This is the first demonstration that phloem-feeding herbivory can affect floral volatile emission, and that the outcome of interaction between herbivory and floral chemistry may differ depending on the herbivore's feeding mode and degree of specialisation. The findings provide new insights into interactions between insect herbivores and plant chemistry

Interview with John N. Winslow, 1986

John Winslow talks about the personal histories and ranching business developed in Menard County by his maternal grandparents, the William L. Black family, and his father Robert S. Winslow

Which symptoms and clinical features correctly identify serious respiratory infection in children attending a paediatric assessment unit?

OBJECTIVE: Parent-reported symptoms are frequently used to triage children, but little is known about which symptoms identify children with serious respiratory infections. The authors aimed to identify symptoms and triage findings predictive of serious respiratory infection, and to quantify agreement between parent and nurse assessment. DESIGN: Prospective diagnostic cohort study. SETTING: Paediatric Assessment Unit, University Hospitals Coventry and Warwickshire NHS Trust. PATIENTS: 535 children aged between 3 months and 12 years with suspected acute infection. METHODS: Parents completed a symptom questionnaire on arrival. Children were triaged by a nurse, who measured routine vital signs. The final diagnosis at discharge was used as the outcome. Symptoms and triage findings were analysed to identify features diagnostic of serious respiratory infection. Agreement between parent and triage nurse assessment was measured and kappa values calculated. RESULTS: Parent-reported symptoms were poor indicators of serious respiratory infection (positive likelihood ratio (LR+) 0.56-1.93) and agreed poorly with nurse assessment (kappa 0.22-0.56). The best predictor was clinical assessment of respiratory distress (LR+ 5.04). Oxygen saturations <94% were highly specific (specificity 95.1%) but had poor sensitivity (35.6%). Tachypnoea (defined by current Advanced Paediatric Life Support standards) offered little discriminatory value. CONCLUSION: Parent-reported symptoms were unreliable discriminators of serious respiratory infection in children with suspected acute infection, and did not correlate well with nurse assessment. Using symptoms to identify higher risk children in this setting is unreliable. Nurse triage assessment of respiratory distress and some vital signs are important predictors

Flame-made ultra-porous TiO<inf>2</inf> layers for perovskite solar cells

© 2016 IOP Publishing Ltd. We report methyl ammonium lead iodide (MAPbI3) solar cells with an ultra-porous TiO2 electron transport layer fabricated using sequential flame aerosol and atomic layer depositions of porous and compact TiO2 layers. Flame aerosol pyrolysis allows rapid deposition of nanostructured and ultra-porous TiO2 layers that could be easily scaled-up for high-throughput low-cost industrial solar cell production. An efficiency of 13.7% was achieved with a flame-made nanostructured and ultra-porous TiO2 electrode that was coated with a compact 2 nm TiO2 layer. This demonstrates that MAPbI3 solar cells with a flame-made porous TiO2 layer can have a comparable efficiency to that of the control MAPbI3 solar cell with the well-established spin-coated porous TiO2 layer. The combination of flame aerosol and atomic layer deposition provides precise control of the TiO2 porosity. Notably, the porosity of the as-deposited flame-made TiO2 layers was 97% which was then fine-tuned down to 87%, 56% and 35% by varying the thickness of the subsequent compact TiO2 coating step. The effects of the decrease in porosity on the device performance are discussed. It is also shown that MAPbI3 easily infiltrates into the flame-made porous TiO2 nanostructure thanks to their high porosity and large pore size