Greenhouse gas emissions and energy use in UK-grown short-day strawberry (Fragaria xananassa Duch) crops

Original article can be found at: http://journals.cambridge.org/ Copyright Cambridge University PressReducing greenhouse gas emissions and optimizing energy consumption are important for mitigating climate change and improving resource use efficiency. Strawberry (Fragaria xananassa Duch) crops are a key component of the UK soft fruit sector and potentially resource-intensive crops. This is the first study to undertake a detailed environmental impact assessment of all methods of UK strawberry production. A total of 14 systems with six additional sub-systems grown for between 1 and 3 years were identified. They were defined by the growing of short-day (Junebearer) or everbearer varieties, organic production, covering with polytunnels or grown in the open, soil-grown (with or without fumigation) or container-grown (with peat or coir substrate) and summer or spring planted. Pre-harvest, the global warming potential varied between 1·5 and 10·3 t CO2 equiv/ha/crop or 0·13 and 1·14 t CO2 equiv/t of class 1 fruit. Key factors included the use of tunnels, mulch and irrigation, sterilization of soil with fumigants and the use of peat substrate. Seasonal crops without covers grown where rotation of sufficient length reduced Verticillium (system 4) were the most efficient. System 4a (that did not use mulch) emitted 0·13 t CO2 equiv/t of class 1 fruit. A second or third cropping year in soil-grown systems prolonged the effect of mulch and soil fumigants. Greenhouse gases from system 4 (with mulch) averaged 0·30 t CO2 equiv/t of class 1 fruit after 3 years of cropping compared to 0·63 and 0·36 t CO2 equiv/t after 1 and 2 years, respectively.Peer reviewe

A self-consistent, multi-variate method for the determination of gas phase rate coefficients, applied to reactions of atmospheric VOCs and the hydroxyl radical

Gas-phase rate coefficients are fundamental to understanding atmospheric chemistry, yet experimental data are not available for the oxidation reactions of many of the thousands of volatile organic compounds (VOCs) observed in the troposphere. Here a new experimental method is reported for the simultaneous study of reactions between multiple different VOCs and OH, the most important daytime atmospheric radical oxidant. This technique is based upon established relative rate concepts but has the advantage of a much higher throughput of target VOCs. By evaluating multiple VOCs in each experiment, and through measurement of the depletion in each VOC after reaction with OH, the OH + VOC reaction rate coefficients can be derived. Results from experiments conducted under controlled laboratory conditions were in good agreement with the available literature for the reaction of nineteen VOCs, prepared in synthetic gas mixtures, with OH. This approach was used to determine a rate coefficient for the reaction of OH with 2,3-dimethylpent-1-ene for the first time; k = 5.7 (±0.3) × 10–11–cm3 molecule−1 s−1. In addition, a further seven VOCs had only two, or fewer, individual OH rate coefficient measurements available in the literature. The results from this work were in good agreement with those measurements. A similar dataset, at an elevated temperature of 323 (±10) K, was used to determine new OH rate coefficients for twelve aromatic, five alkane, five alkene and three monoterpene VOC + OH reactions. In OH relative reactivity experiments that used ambient air at the University of York, a large number of different VOCs were observed, of which 23 were positively identified. 19 OH rate coefficients were derived from these ambient air samples, including ten reactions for which data was previously unavailable at the elevated reaction temperature of T = 323 (±10) K

To grade or not to grade: balancing formative and summative assessment in post-16 teacher trainee observations

The issue of whether trainee teachers in the post-16 sector should have their classroom practice graded has been debated for a number of years. The case for training courses retaining an emphasis on written and verbal ‘developmental’ feedback at the expense of ‘judgements’ appears to be lost. This article is set within the context of an ever-growing culture of performativity in English further education colleges, where grading is regarded as an essential requirement to ensure high quality teaching. Tensions are explored between stakeholders who call for graded observations of trainees’ classroom performance (e.g. Ofsted and FEC quality assurance managers), and classroom-based trainers and researchers who argue that grading is too judgemental and compromises the formative and developmental progress of trainees. The rationale for trainee teachers to have their classroom practice graded is contrasted with evidence that highlights the negative results of grading. This article reports findings from the evaluation of an innovative, alternative strategy that addresses Ofsted’s central requirement for trainees to know ‘where they are’ in their development by offering a middle way between grading and not grading trainees’ classroom performance

New Scunthorpe Rhythm and Blues I

This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library

this piece is about you

This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library

Rhythmic, diatonic and microtonal structures in musical composition Method and notation (compositions 1993-1998)

SIGLEAvailable from British Library Document Supply Centre- DSC:DXN054997 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

New Scunthorpe Rhythm and Blues I

This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library