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Energy embodied in household cookery: the missing part of a sustainable food system? Part 1: A method to survey and calculate representative recipes
This paper firstly reviews the current state of knowledge on sustainable cookery and the environmental impacts of the food consumption phase. It then uses the example of a dish of roast beef and Yorkshire pudding to explore energy use in food production and consumption. Part 1 of this paper conducts a meta-analysis of 33 roast beef and Yorkshire pudding recipes in order to create a representative recipe for analysis. Part 2 of this paper then uses life cycle assessment and energy use data is coupled with the representative recipe of roast beef and Yorkshire pudding, to calculate the embodied energy of the meal. Seven interventions are modelled to illustrate how sustainable cookery can play a role as part of a sustainable food system. Interventions show that sustainable cookery has the potential to reduce cookery related energy use by 18%, and integrating sustainable cookery within a sustainable food system has the potential to reduce the total energy use by 55%. Finally, the paper discusses the issue of how the adoption of the sustainable cookery agenda may help or hinder attempts to shift consumers towards sustainable diets
Evidence for a colour dependence in the size distribution of main belt asteroids
We present the results of a project to detect small (~1 km) main-belt
asteroids with the 3.6 meter Canada-France-Hawaii Telescope (CFHT). We observed
in 2 filters (MegaPrime g' and r') in order to compare the results in each
band. Owing to the observational cadence we did not observe the same asteroids
through each filter and thus do not have true colour information. However
strong differences in the size distributions as seen in the two filters point
to a colour-dependence at these sizes, perhaps to be expected in this regime
where asteroid cohesiveness begins to be dominated by physical strength and
composition rather than by gravity. The best fit slopes of the cumulative size
distributions (CSDs) in both filters tend towards lower values for smaller
asteroids, consistent with the results of previous studies. In addition to this
trend, the size distributions seen in the two filters are distinctly different,
with steeper slopes in r' than in g'. Breaking our sample up according to
semimajor axis, the difference between the filters in the inner belt is found
to be somewhat less pronounced than in the middle and outer belt, but the CSD
of those asteroids seen in the r' filter is consistently and significantly
steeper than in g' throughout. The CSD slopes also show variations with
semimajor axis within a given filter, particularly in r'. We conclude that the
size distribution of main belt asteroids is likely to be colour dependent at
kilometer sizes and that this dependence may vary across the belt.Comment: 28 pages, 5 figures, submitted to the Astronomical Journa
On the Low Energy Decrease in Galactic Cosmic Ray Secondary/Primary Ratios
Galactic cosmic ray (GCR) secondary/primary ratios such as B/C and (Sc+Ti+V)/Fe are commonly used to determine the mean amount of interstellar material through which cosmic rays travel before escaping from the Galaxy (Λ_(esc)). These ratios are observed to be energy-dependent, with a relative maximum at ~1 GeV/nucleon, implying a corresponding peak in Λ_(esc). The decrease in Λ_(esc) at energies above 1 GeV/nucleon is commonly taken to indicate that higher energy cosmic rays escape more easily from the Galaxy. The decrease in Λ_(esc) at energies <1 GeV/nuc is more controversial; suggested possibilities include the effects of a galactic wind or the effects of distributed acceleration of cosmic rays as they pass through the interstellar medium. We consider two possible explanations for the low energy decrease in Λ_(esc) and attempt to fit the combined, high-resolution measurements of secondary/primary ratios from ~0.1 to 35 GeV/nuc made with the CRIS instrument on ACE and the C2 experiment on HEAO-3. The first possibility, which hypothesizes an additional, local component of low-energy cosmic rays that has passed through very little material, is found to have difficulty simultaneously accounting for the abundance of both B and the Fe-secondaries. The second possibility, suggested by Soutoul and Ptuskin, involves a new form for Λ_(esc) motivated by their diffusion-convection model of cosmic rays in the Galaxy. Their suggested form for Λ_(esc)(E) is found to provide an excellent fit to the combined ACE and HEAO data sets
Design and operation of a prototype interaction point beam collision feedback system for the International Linear Collider
A high-resolution, intratrain position feedback system has been developed to
achieve and maintain collisions at the proposed future electron-positron
International Linear Collider (ILC). A prototype has been commissioned and
tested with a beam in the extraction line of the Accelerator Test Facility at
the High Energy Accelerator Research Organization in Japan. It consists of a
stripline beam position monitor (BPM) with analogue signal-processing
electronics, a custom digital board to perform the feedback calculation, and a
stripline kicker driven by a high-current amplifier. The closed-loop feedback
latency is 148 ns. For a three-bunch train with 154 ns bunch spacing, the
feedback system has been used to stabilize the third bunch to 450 nm. The
kicker response is linear, and the feedback performance is maintained, over a
correction range of over 60 {\mu}m. The propagation of the correction has
been confirmed by using an independent stripline BPM located downstream of the
feedback system. The system has been demonstrated to meet the BPM resolution,
beam kick, and latency requirements for the ILC
Presence of 5-hydroxyguaiacyl units as native lignin constituents in plants as seen by Py-GC/MS
Instituto de Recursos Naturales y Agrobiología de Sevilla, CSIC, P.O. Box 1052, 41080-Seville, Spain
2Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
E-mail address: [email protected] (J.C. del Río)The presence of 5-hydroxyguaiacyl moieties in the lignin from several plants has been assessed by Py-GC/MS. Different woody (eucalypt) and nonwoody (flax, hemp, kenaf, jute, sisal and abaca) angiosperms were selected for this study. The pyrolysis of whole fibers released lignin-derived products with p-hydroxyphenyl, guaiacyl and syringyl structures. Indeed, a series of compounds having a 5-hydroxyguaiacyl nuclei, including 3-methoxycatechol, 5-vinyl-3-methoxycatechol and 5-propenyl-3-methoxycatechol, were detected and identified in all samples, although in lower amounts than the normal guaiacyl and syringyl compounds. The analysis of the lignins isolated from the same plants also indicated the presence of 5-hydroxyguaiacyl moieties in the isolated lignins. These compounds are supposed to arise from the pyrolysis of 5-hydroxyguaiacyl moieties, which are supposed to be native constituents of lignin in plants forming benzodioxane substructures.This study has been supported by the Spanish Ministerio de Ciencia y Tecnología (MCyT) and FEDER funds (project AGL2005-01748) and the EU project BIORENEW (NMP2-CT-2006-026456). We thank CELESA S.A. (Tortosa, Spain) for providing the nonwoody plant samples, and ENCE for providing the eucalypt wood sample.Peer reviewe
The C-Band All-Sky Survey: Instrument design, status, and first-look data
The C-Band All-Sky Survey (C-BASS) aims to produce sensitive, all-sky maps of
diffuse Galactic emission at 5 GHz in total intensity and linear polarization.
These maps will be used (with other surveys) to separate the several
astrophysical components contributing to microwave emission, and in particular
will allow an accurate map of synchrotron emission to be produced for the
subtraction of foregrounds from measurements of the polarized Cosmic Microwave
Background. We describe the design of the analog instrument, the optics of our
6.1 m dish at the Owens Valley Radio Observatory, the status of observations,
and first-look data.Comment: 10 pages, 11 figures, published in Proceedings of SPIE MIllimeter,
Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy V
(2010), Vol. 7741, 77411I-1 - 77411I-1
Constraints on the nucleosynthesis of refractory nuclides in galactic cosmic rays
Abundances of the isotopes of the refractory elements Ca, Fe, Co, and Ni in the galactic cosmic-ray source are compared with corresponding abundances in solar-system matter. For the 12 nuclides considered, relative abundances agree to within a factor of 2, and typically within 20–30%. In addition, comparisons of cosmic-ray abundances with model calculations of supernova yields are used to argue that cosmic rays contain contributions from stars with a broad range of masses. Based on these and other results we suggest that cosmic rays probably represent a sample of contemporary interstellar matter, at least for refractory species
A measurement of cosmic ray deuterium from 0.5–2.9 GeV/nucleon
The rare isotopes ^(2)H and ^(3)He in cosmic rays are believed to originate mainly from the interaction of high energy protons and helium with the galactic interstellar medium. The unique propagation history of these rare isotopes provides important constraints on galactic cosmic ray source spectra and on models for their propagation within the Galaxy. Hydrogen and helium isotopes were measured with the balloon-borne experiment, IMAX, which flew from Lynn Lake, Manitoba in 1992. The energy spectrum of deuterium between 0.5 and 3.2 GeV/nucleon measured by the IMAX experiment as well as previously published results of ^(3)He from the same instrument will be compared with predictions of cosmic ray galactic propagation models. The observed composition of the light isotopes is found to be generally consistent with the predictions of the standard Leaky Box Model derived to fit observations of heavier nucle
Evaluation of the impact of a school gardening intervention on children's fruit and vegetable intake: a randomised controlled trial.
Background: Current academic literature suggests that school gardening programmes can provide an interactive environment with the potential to change children’s fruit and vegetable intake. This is the first cluster randomised controlled trial (RCT) designed to evaluate whether a school gardening programme can have an effect on children’s fruit and vegetable intake.
Methods: The trial included children from 23 schools; these schools were randomised into two groups, one to receive the Royal Horticultural Society (RHS)-led intervention and the other to receive the less involved Teacher-led intervention. A 24-hour food diary (CADET) was used to collect baseline and follow-up dietary intake 18 months apart. Questionnaires were also administered to evaluate the intervention implementation.
Results: A total of 641 children completed the trial with a mean age of 8.1 years (95% CI: 8.0, 8.4). The unadjusted results from multilevel regression analysis revealed that for combined daily fruit and vegetable intake the Teacher-led group had a higher daily mean change of 8 g (95% CI: −19, 36) compared to the RHS-led group -32 g (95% CI: −60, −3). However, after adjusting for possible confounders this difference was not significant (intervention effect: −40 g, 95% CI: −88, 1; p = 0.06). The adjusted analysis of process measures identified that if schools improved their gardening score by 3 levels (a measure of school gardening involvement - the scale has 6 levels from 0 ‘no garden’ to 5 ‘community involvement’), irrespective of group allocation, children had, on average, a daily increase of 81 g of fruit and vegetable intake (95% CI: 0, 163; p = 0.05) compared to schools that had no change in gardening score.
Conclusions: This study is the first cluster randomised controlled trial designed to evaluate a school gardening intervention. The results have found very little evidence to support the claims that school gardening alone can improve children’s daily fruit and vegetable intake. However, when a gardening intervention is implemented at a high level within the school it may improve children’s daily fruit and vegetable intake by a portion. Improving children’s fruit and vegetable intake remains a challenging task
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